JP2022145482A - Pump with flow detection function, pump abnormality detection system - Google Patents

Abstract

To provide a pump with a flow detecting function capable of detecting a flow state in a flow passage while maintaining peristalsis type pump performance, and a pump abnormality detecting system.SOLUTION: A pump 1 with a flow detecting function includes a flow passage 10 having a flow passage wall 11 displaced in accordance with change in pressure of fluid flowing in an inside thereof, a pump 2 peristaltically moving the flow passage 10 by moving a plurality of pressure-contact pieces 22 coming in press-contact with the flow passage wall 11, and a pressure detector 3 having a pressure receiver 3b which is brought into contact with the flow passage wall 11 in a pressing region 100 in which the plurality of pressure-contact pieces 22 presses the flow passage wall 11 and at a position opposite across the plurality of the pressure-contact pieces 22 and the flow passage 10.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a pump with a flow detection function and a pump abnormality detection system.

The following patent document 1 describes a peristaltic type in which a liquid flowing in a flexible infusion tube that connects a medical container containing the liquid and a human body and is forcibly flowed by peristaltic movement of the infusion tube. An infusion pump is disclosed. This peristaltic infusion pump has multiple closure points that block the flow of liquid in the infusion tube, one closure point and another closure point as the peristaltic movement for fluid delivery progresses. a volume change means for changing the volume of the closed region sandwiched between; a pressure detection means for detecting the pressure in the infusion tube in the closed region; air bubble detection means for determining whether or not there is air entrapped in the infusion tube based on a change in the amount of pressure change in the infusion tube.

JP 2016-220958 A

In the prior art described above, while it is possible to detect air bubbles in the infusion tube, there is a section in the vicinity of the pressure detecting means where the pressure contact is separated from the infusion tube and does not crush the infusion tube. In the peristaltic pump, the pressure on the upstream side of the pump becomes lower as the section where the press contact crushes the infusion tube becomes longer, so that the pumping capacity can be increased. For this reason, in the above-described prior art, there is a problem that the section in which the press contact crushes the infusion tube is short and divided, so that the sucking capacity of the pump becomes low.

The present disclosure has been made in view of the above problems, and aims to provide a pump with a flow detection function and a pump abnormality detection system that can detect the flow state in the flow path while maintaining the performance of the peristaltic pump. do.

(1) A pump with a flow detection function according to an aspect of the present disclosure includes a flow path having a flow wall that is displaced by a pressure change of a fluid flowing inside, and by moving a plurality of pressure contacts that are in pressure contact with the flow wall, a pump unit for peristaltic movement of the flow channel; and a pressure detecting portion having a pressure receiving portion that contacts with the pressure detecting portion.

According to the pump with a flow detection function according to this aspect, the pressure receiving portion of the pressure detecting portion contacts the flow wall of the flow channel at a position opposite to the plurality of press contacts that cause peristaltic motion of the flow channel. do. The position where the pressure-receiving part contacts the flow wall is in the pressure range where the plurality of pressure contacts presses the flow wall while contacting the flow wall. is ensured for a long time, and a decrease in the pump's suction ability can be suppressed. Therefore, it is possible to detect the state of flow in the channel while maintaining the performance of the peristaltic pump.

(2) In the pump with a flow detection function according to aspect (1), the pressure receiving portion is located at a position downstream of the flow path from a position where the pressing pressure of the pressure contact to the flow wall is highest. may be in contact with

In this case, if clogging occurs in the flow path on the downstream side of the pump section, the reverse flow of the fluid can be prevented at the position where the pressing pressure of the press contact against the flow wall in the pump section is the highest. The pressure receiving portion can detect an increase in the internal pressure of the flow path due to the reverse flow of the fluid caused by the clogging of the flow path.

(3) In the pump with a flow detection function of aspect (1) or (2), the pressing range includes a closing range in which the plurality of pressure contacts move while closing the flow path, and the closing range is formed with both-end closing portions sandwiched between a position at which the pressure contact closes the flow path and a position at which the adjacent pressure contact closes the flow path. The flow wall may be contacted at a position within a range from the downstream end of the range to the upstream side of the flow path for the formation length of one of the both end closures.

In a peristaltic pump, the pressure range of the flow path by a plurality of press contacts includes a closing range in which the inner diameter of the flow path becomes zero due to the pressing of the pressure contacts. A double-ended closure is formed which is pinched by the child. At the downstream end of the closing range of the both-end closing portion, the pressing force of the pressure contact on the flow wall is weakened, so that the inner diameter of the flow path changes from zero to positive, causing a reverse flow of fluid from the downstream side of the flow path where the pressure is high. Since the pressure-receiving part is located within the range of the formation length of one of the both-ends closing parts from the downstream end of the closing range toward the upstream side of the flow path, such a backflow immediately occurs. It is possible to reach the pressure receiving part without passing through the part where the path is closed. As a result, the pressure receiving portion can efficiently detect an increase in the internal pressure of the flow path due to the reverse flow of the fluid. Moreover, since the both-ends closing portion is still closed by the pressure contact on the downstream side, it is possible to prevent the fluid from flowing backward to the upstream side of the pump portion. In addition, if clogging occurs in the flow path downstream of the pump section, the increase in internal pressure of the flow path due to the backflow of the fluid becomes more pronounced than in the above-described normal backflow of the fluid. Clogging of the channel can be detected by comparing with the reverse flow.

(4) In the pump with a flow detection function of aspect (1), the pressing range includes a closing range in which the plurality of press contacts move while closing the flow path, and the pump section A press contact driving section may be provided that gradually narrows the intervals between the plurality of press contacts toward the downstream end of the range.

In this case, in the closed range where the inner diameter of the flow path becomes zero due to the pressing force of the pressure contact, the distance between the pressure contacts gradually narrows toward the downstream side, increasing the pressure in the flow path. As a result, the difference between the pressure in the flow path and the pressure in the flow path on the downstream side when the pressure contact on the downstream side is separated from the closed range becomes small, and the occurrence of backflow and pulsation can be suppressed. can. This reduces noise and increases the detection accuracy of the pressure detection unit.

(5) In the pump with a flow detection function according to the mode (4), the pressure receiving portion may contact the flow wall at a half position on the downstream side of the closing range.

When the distance between multiple pressure contacts gradually narrows toward the downstream end of the closing range, the change in pressure in the flow path when the pressure contact on the downstream side leaves the closing range is Almost never, but if clogging occurs in the flow path downstream of the pump section, the clogging of the flow path on the downstream side will cause the pressure in the flow path on the downstream side to rise more than usual, so the downstream When the pressure contact on the side leaves the closed area, a reverse flow of fluid occurs and the pressure in the flow path changes. Since the pressure change due to the backflow of the fluid is likely to occur downstream of the closed range, the backflow of the fluid can be easily detected by installing the pressure receiving section at the downstream half position of the closed range.

(6) In the pump with a flow detection function according to mode (4) or (5), the closing range includes a position where the pressure contact closes the flow path and a position where the pressure contact closes the flow path. and the pressure receiving portion extends from the downstream end of the closing range toward the upstream side of the flow path within the range of the minimum forming length of the both ends closing portion. may contact the flow wall at the position of

In this case, since the pressure-receiving portion is located within the minimum formation length of the both-end closing portions from the downstream end of the closed range toward the upstream side of the flow channel, the pressure in the flow channel in the closed range can be detected. If the flow path is damaged and fluid leaks, the maximum value of the pressure in the flow path in the closed range will be lower than normal, making it easier to detect an abnormality in the flow path.

(7) In the pump with a flow detection function according to any one of aspects (1) to (6), the pressure detection section may include a cantilever that bends and deforms according to changes in the internal pressure of the pressure receiving section.

In this case, since the cantilever detects changes in the internal pressure of the pressure receiving portion with high sensitivity, it is possible to detect pressure in a wide range from strong pressure of the pressure contact to weak pressure changes in the flow path. Therefore, the pressure receiving part can be installed in the pressure range of the flow path pressed by the pressure contact, and the flow condition of the fluid can be detected from the outside of the flow path without lowering the liquid feeding performance of the pump part. In addition, since the pressure detection section can also measure the pressure (timing and pressure) of the pressure contact, it is possible to simultaneously detect the operation status of the pump section.

(8) In the pump with a flow detection function of aspect (7), the pressure detection section may include a cavity housing that forms a differential pressure chamber that communicates with the inside of the pressure receiving section with the cantilever interposed therebetween.

In this case, since the cantilever is less likely to be affected by the outside air, it is possible to detect the displacement of the flow path due to the pressure change of the fluid with high accuracy.

(9) In the pump with a flow detection function according to any one of aspects (1) to (8), the pressure receiving portion includes an elastic body that contacts the flow wall and presses against the flow wall via the elastic body. and a duct.

In this case, since the conduit of the pressure receiving portion is in close contact with the flow wall via the elastic body, the responsiveness of the bending deformation of the cantilever accompanying the displacement of the flow wall is improved, and the shape change of the flow channel can be detected with high sensitivity. be able to.

(10) In the pump with a flow detection function of aspect (9), the elastic body may be softer than the flow wall.

In this case, for example, when the flow wall expands, before the flow wall is completely displaced in the thickness direction by the internal pressure of the fluid, the elastic body that is softer than the flow wall begins to displace. The responsiveness to changes in internal pressure is improved, and changes in the shape of the flow path can be detected with high sensitivity.

(11) In the pump with a flow detection function according to any one of aspects (1) to (8), the pressure receiving portion may include a bellows pipe that contacts the flow wall.

In this case, since the bellows pipe of the pressure receiving portion elastically adheres to the flow wall, responsiveness to changes in the internal pressure of the pressure receiving portion due to displacement of the flow wall is improved, and changes in the shape of the flow channel can be detected with high sensitivity. be able to.

(12) In the pump with a flow detection function according to any one of aspects (1) to (8), the pressure receiving section may include a balloon body that contacts the flow wall.

In this case, since the balloon body of the pressure-receiving portion elastically adheres to the flow wall, the responsiveness to changes in the internal pressure of the pressure-receiving portion accompanying displacement of the flow wall is improved, and changes in the shape of the flow channel can be detected with high sensitivity. be able to.

(13) In the pump with a flow detection function according to any one of aspects (1) to (12), the pressure detection section further includes a biasing section that biases the pressure receiving section toward the flow wall. good too.

In this case, since the pressure receiving portion is urged by the urging portion to maintain close contact with the flow wall, responsiveness to changes in the internal pressure of the pressure receiving portion due to displacement of the flow wall is improved. Shape change can be detected with high sensitivity.

(14) A pump abnormality detection system according to an aspect of the present disclosure includes a pump with a flow detection function according to any one of aspects (1) to (13), and a pressure detection unit included in the pump with a flow detection function. and a control device that determines whether or not there is an abnormality in the pump with a flow detection function based on the signal.

In this case, while maintaining the performance of the peristaltic pump, the flow state in the flow path is monitored, and if an abnormality occurs in the pump section or flow path, the abnormality is promptly detected and the pump section can be reflected in pump control such as stopping operation or slowing down.

(15) A pump abnormality detection system according to an aspect of the present disclosure includes a pump with a flow detection function according to any one of aspects (4) to (6), and a pressure detection unit included in the pump with a flow detection function. and a control device for determining whether or not there is an abnormality in the pump with a flow detection function based on the signal from the pressure detector, wherein the control device controls the pressure detection unit after the pressure contact is separated from the downstream end of the closing range. is higher than normal, it is determined that the downstream side of the channel is clogged.

When the distance between multiple pressure contacts gradually narrows toward the downstream end of the closing range, the change in pressure in the flow path when the pressure contact on the downstream side leaves the closing range is Although almost never, when clogging occurs in the flow path on the downstream side of the pump section, the clogging of the flow path on the downstream side causes the pressure in the flow path to rise more than usual. Therefore, when the signal output from the pressure detection unit after the press contact has left the downstream end of the closing range is higher than normal, it is determined that the downstream side of the flow path is clogged. can be done.

(16) A pump abnormality detection system according to an aspect of the present disclosure includes a pump with a flow detection function according to any one of aspects (4) to (6), and a pressure detection unit included in the pump with a flow detection function. and a control device for determining whether or not there is an abnormality in the pump with a flow detection function based on the signal from the pressure detector, wherein the control device controls the pressure detection unit at the timing when the pressure contact moves away from the downstream end of the closing range. is lower than normal, it is determined that the upstream side of the flow path is leaking.

When the distance between multiple pressure contacts gradually narrows toward the downstream end of the closing range, the pressure in the flow path increases when the both-ends closing parts reach the minimum formed length under normal conditions (normal conditions). become maximum. Therefore, if the signal output from the pressure detection unit at the timing when the press contact moves away from the downstream end of the closed range is lower than normal, it is determined that the upstream side of the flow path is leaking. be able to.

According to the above aspect of the present disclosure, it is possible to provide a pump with a flow detection function and a pump abnormality detection system that can detect the state of flow in a flow path while maintaining peristaltic pump performance.

1 is a configuration diagram of a pump with a flow detection function and a pump abnormality detection system according to a first embodiment; FIG. 4 is a configuration diagram of a detection unit main body of the pressure detection unit according to the first embodiment; FIG. 2 is a plan view showing a configuration example of a cantilever according to the first embodiment; FIG. 3 is a circuit diagram showing a configuration example of an analog circuit section according to the first embodiment; FIG. FIG. 4 is a developed view showing a flow path straightened for explaining the movement of the pressure contact according to the first embodiment; 7 is a graph showing changes in the internal pressure of the flow path and the output value of the pressure detection unit according to the movement of the pressure contact according to the first embodiment; 7 is a graph showing changes in the internal pressure of the flow path and the output value of the pressure detection section when clogging occurs in the flow path on the downstream side of the pump section according to the first embodiment. 5 is a graph showing changes over time in the output of the pressure detection unit (differential pressure sensor) according to the first embodiment. 7 is a graph showing changes in output over time when an absolute pressure sensor is used as a pressure detection unit as a comparative example. FIG. 10 is a configuration diagram showing a main part of a pump with a flow detection function according to a second embodiment; FIG. 11 is a configuration diagram showing a modified example of the main part of the pump with a flow detection function according to the second embodiment; FIG. 11 is a configuration diagram showing a modified example of the main part of the pump with a flow detection function according to the second embodiment; FIG. 11 is a configuration diagram of a pump with a flow detection function and a pump abnormality detection system according to a third embodiment; FIG. 11 is an explanatory diagram for explaining movements of the first pressure contact piece and the second pressure contact piece according to the third embodiment; 15 is a graph showing changes in the output value (absolute pressure) of the pressure detection unit according to the movement of the first pressure contact piece and the second pressure contact piece shown in FIG. 14; FIG. FIG. 15 is a graph showing changes in the output value (differential pressure) of the pressure detection unit according to the movement of the first pressure contact piece and the second pressure contact piece shown in FIG. 14; FIG. 11 is an explanatory diagram illustrating movements of the first pressure contact piece and the second pressure contact piece when the flow path is damaged and fluid leaks according to the third embodiment; 18 is a graph showing changes in the output value (absolute pressure) of the pressure detection unit according to movements of the first pressure contact piece and the second pressure contact piece shown in FIG. 17; 18 is a graph showing changes in the output value (differential pressure) of the pressure detection unit according to the movement of the first pressure contact piece and the second pressure contact piece shown in FIG. 17;

Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a configuration diagram of a pump 1 with a flow detection function and a pump abnormality detection system 200 according to the first embodiment.
As shown in FIG. 1 , a pump 1 with a flow detection function includes a pump section 2 that causes a flow path 10 to perform peristaltic motion, and a pressure detection section 3 that detects the pressure inside the flow path 10 . The pump abnormality detection system 200 determines whether or not there is an abnormality in the pump 1 with a flow detection function based on the signal output from the pump 1 with a flow detection function and the pressure detection unit 3 of the pump 1 with a flow detection function. a device 201;

The channel 10 has a flow wall 11 that is displaced by pressure changes of the fluid flowing inside. The channel 10 of the present embodiment is a so-called liquid-sending tube having at least flexibility and elasticity, and is elongated with a constant inner diameter (cross-sectional area). In addition, depending on the type of fluid, application, etc., the flow wall 11 may be subjected to various treatments such as oxidation treatment as necessary, or may be given various properties such as heat resistance and transparency. . The flow path 10 is connected to a liquid tank 4 that stores fluid on the upstream side of the pump section 2 .

The pump unit 2 is a so-called roller pump that causes the flow path 10 to perform peristaltic motion, sucks the fluid stored in the liquid tank, and discharges the fluid while pulsating it. As long as the pump unit 2 is a peristaltic pump, it may be not only a roller pump type but also a peristaltic finger type pump as disclosed in the prior art document. Since the channel 10 has at least flexibility and elasticity, the flow wall 11 undulates and contracts according to the pulsation of the fluid.

The pump unit 2 includes a pump main body 21 in which a roller accommodating portion 21a having a circular shape in plan view is formed, and a plurality of press contacts 22 and a press contact driving portion 23 arranged in the roller accommodating portion 21a. In the pump main body 21, the channel 10 is arranged in a U shape in a plan view along the peripheral wall of the roller accommodating portion 21a. The flow path 10 surrounds the plurality of press contacts 22 from the outside.

The pressure contact driving portion 23 is a central roller rotatable in the central portion of the roller accommodating portion 21a. The press contact driving portion 23 functions as a guide roller that guides the rotation of the plurality of press contacts 22 . The plurality of pressure contacts 22 are compression rollers that are evenly arranged in the circumferential direction so as to surround the pressure contact drive portion 23 . In the illustrated example, six press contacts 22 are arranged, but the number of press contacts 22 is not limited to six.

The six pressure contacts 22 are arranged so as to be in sliding contact with each other in the circumferential direction and in sliding contact with the pressure contact driving portion 23, and are pressed while rotating via a power transmission mechanism such as a gear train (not shown). It is capable of revolving around the child driving portion 23 .
The revolving direction of the six press contacts 22 is, for example, the direction from the upstream side to the downstream side of the flow path 10, as indicated by an arrow M1. Further, the directions of rotation of the six pressure contacts 22 are opposite to the directions of revolution, as indicated by arrows M2 in FIG.

Further, the six pressure contacts 22 are capable of crushing the flow path 10 housed in the roller housing portion 21a during the process of revolution. As a result, the press contact 22 can be rotated while the flow path 10 is crushed, and the fluid can be sent downstream. Furthermore, when the pressure contact 22 rides on the flow path 10 and moves downstream while crushing the flow path 10 , a negative pressure is generated in the flow path 10 by the movement of the pressure contact 22 . Fluid can be sucked into the channel 10 .

By repeating these operations, the flow path 10 can be periodically squeezed using the plurality of pressure contacts 22, and the fluid can be supplied (fluid-fed) to the downstream side while causing the flow path 10 to perform peristaltic motion. becomes possible. That is, the pump part 2 can pump the fluid downstream by periodically squeezing the flow path 10 . In addition, since the revolution speed of the press contact 22 changes according to the number of rotations of the pump portion 2 (press contact driving portion 23), the fluid feeding speed can be controlled. Note that the operation of the pump unit 2 is controlled by the control device 201 .

The pressure detection section 3 includes a detection section body 3a and a pressure receiving section 3b. The pressure receiving portion 3 b includes an elastic body 37 that contacts the flow wall 11 of the flow path 10 and a conduit 38 that is pressed against the flow wall 11 via the elastic body 37 . The elastic body 37 has elasticity to elastically deform according to the displacement of the flow wall 11 . This elastic body 37 is preferably made of a material softer than the flow wall 11 .

The elastic body 37 of the present embodiment is formed of a gel body having elasticity capable of being elastically deformed according to the displacement of the flow wall 11 and sealing properties capable of sealing the opening end of the pipe line 38 . The pipe line 38 is a cylindrical body that is removably attached to the pump main body 21 and is made of a pipe material that is harder than the elastic body 37 . One end of the conduit 38 is closed by the elastic body 37, and the other end of the conduit 38 is connected to the detector main body 3a.

FIG. 2 is a configuration diagram of the detection unit main body 3a of the pressure detection unit 3 according to the first embodiment.
As shown in FIG. 2, the detection section main body 3a includes a sensor substrate 31, a cantilever 32, an analog circuit section 33, a digital processing section 34, and a cavity housing 35. As shown in FIG.
The sensor board 31 is, for example, a printed circuit board. A through-hole 31a is formed through the sensor substrate 31 in the thickness direction. The through hole 31a communicates with the interior of the conduit 38 of the pressure receiving portion 3b.

The cavity housing 35 is formed in a cylindrical shape with a bottom, and is connected to the surface of the sensor substrate 31 opposite to the surface to which the conduit 38 is connected so as to surround the through hole 31a. The cantilever 32 is arranged inside the cavity housing 35 . Inside the cavity housing 35, the cantilever 32 is attached to the open end of a cylindrical lever support 36 connected to surround the through hole 31a.

The internal space of the cavity housing 35 is divided into a pressure receiving chamber 30A and a differential pressure chamber 30B with the cantilever 32 interposed therebetween. The pressure receiving chamber 30A and the differential pressure chamber 30B communicate with each other through a communication hole 42 provided in the cantilever 32. As shown in FIG. The conduit 38 of the pressure receiving portion 3b and the through hole 31a of the sensor substrate 31 communicate with the pressure receiving chamber 30A. The differential pressure chamber 30B is an airtight chamber communicating with the pressure receiving chamber 30A with the cantilever 32 interposed therebetween.

According to this configuration, for example, when the flow wall 11 of the flow path 10 is displaced and swells, the elastic body 37 is elastically deformed, thereby compressing the gas in the conduit 38, thereby compressing the pressure receiving chamber communicating with the through hole 31a. 30A pressure increases. Then, the cantilever 32 can detect the differential pressure between the pressure receiving chamber 30A and the differential pressure chamber 30B by flexural deformation, and the shape change of the flow path 10 due to the increase in the internal pressure of the flow path 10 can be detected.

FIG. 3 is a plan view showing a configuration example of the cantilever 32 according to the first embodiment.
The cantilever 32 is formed on a semiconductor substrate 40 such as an SOI substrate, for example. A gap G1 and a gap G2 are provided in the semiconductor substrate 40, and a lever main body 41 and a lever support portion 43 of the cantilever 32 are formed. The gap G1 and the gap G2 serve as communication holes 42 that communicate the pressure receiving chamber 30A and the differential pressure chamber 30B.

The base end portion 41b of the lever main body 41 is connected to the lever support portion 43 so as to be cantilevered, and the distal end portion 41a thereof is a free end. The lever body 41 has a plate shape extending in one direction from the base end portion 41b toward the tip end portion 41a, and is flexurally deformed according to the pressure difference between the pressure receiving chamber 30A and the differential pressure chamber 30B of the cavity housing 35. As shown in FIG.

The gap G1 is a U-shaped (C-shaped) groove formed between the semiconductor substrate 40 and the outer peripheral edge of the lever body 41 and penetrating the semiconductor substrate 40 in the thickness direction. The gap G2 is a U-shaped (C-shaped) groove formed in the base end portion 41b of the lever body 41 and penetrating the lever body 41 in the thickness direction. The gap G<b>2 is arranged at the center of the lever body 41 in the width direction at the base end 41 b of the lever body 41 .

Two lever support portions 43 are arranged side by side in the width direction of the lever body 41 across a gap G2, connect the lever body 41 and the semiconductor substrate 40, and support the lever body 41 in a cantilever state. . The support widths of the two lever support portions 43 in the width direction of the lever main body 41 are made equal. Therefore, when the lever main body 41 is flexurally deformed, the stress per unit area acting on one lever support portion 43 is equal to the stress per unit area acting on the other lever support portion 43 .

A doped layer 44 (impurity semiconductor layer), which is a piezoresistor (resistive element), is formed on the semiconductor substrate 40 so as to include the lever body 41 . The doped layer 44 is formed by doping a dopant (impurity) such as phosphorus by various methods such as ion implantation and diffusion. A portion of the doped layer 44 where the lever main body 41 is formed (including the portion formed on the lever support portion 43) functions as a resistor R1 (differential pressure detection resistor Rsen1).

The resistance value of the resistor R1 changes according to the deflection amount of the lever support portion 43 . Although not shown, an electrode made of a conductive material (for example, Au (gold) or the like) having an electrical resistivity lower than that of the doped layer 44 is formed on a part of the upper surface of the doped layer 44 . This electrode functions as a first end and a second end of the resistor R1 (differential pressure detection resistor Rsen1).

Returning to FIG. 2, the analog circuit section 33 is a circuit that performs analog processing for detecting displacement according to bending deformation of the lever body 41 . This analog circuit section 33 is an AFE (analog front end). The analog circuit section 33 is arranged inside the cavity housing 35, that is, in the differential pressure chamber 30B.

FIG. 4 is a circuit diagram showing a configuration example of the analog circuit section 33 according to the first embodiment.
As shown in FIG. 4 , the analog circuit section 33 includes a Wheatstone bridge circuit 45 and a differential amplifier circuit 46 . The Wheatstone bridge circuit 45 includes a resistor R1 (differential pressure detection resistor Rsen1) included in the cantilever 32, a resistor R2, a resistor R3, and a resistor R4.

The resistor R1 (differential pressure detection resistor Rsen1) has a first end connected to the reference voltage circuit Vref and a second end connected to the node N1. Change. Resistor R1 is, for example, a piezoresistor (doped layer 44). The resistor R2 has a first end connected to the node N1 and a second end connected to the power supply GND.

The resistor R3 has a first end connected to the reference voltage circuit Vref and a second end connected to the node N2. The resistor R4 has a first end connected to the node N2 and a second end connected to the power supply GND. The resistor R1 is configured within the cantilever 32, and the resistors R3 and R4 are external resistors provided outside the cantilever 32. FIG.

The resistor R2 (reference resistor Rref1) is, for example, a resistor formed to have the same temperature characteristics as the resistor R1, and may be configured within the cantilever 32 or may be provided outside near the cantilever 32. good too. By matching the temperature characteristics of the resistor R1 and the resistor R2, the analog circuit section 33 can reduce the influence of temperature fluctuations on the detection result.

The differential amplifier circuit 46 is, for example, a measurement amplifier (instrumentation amplifier), amplifies the potential difference between the node N1 and the node N2, and outputs it as an output signal. This potential difference becomes a value corresponding to the change in the resistance value of the piezoresistor, that is, a value based on the displacement of the cantilever 32 . The differential amplifier circuit 46 has an inverting input terminal (-terminal) connected to the node N1 and a non-inverting input terminal (+terminal) connected to the node N2.

The digital processing unit 34 shown in FIG. 2 is, for example, a digital processing circuit such as a microcontroller, and converts the output waveform data corresponding to the differential pressure detected by the analog circuit unit 33 into pressure fluctuation information. The digital processing unit 34 is mounted (arranged) on, for example, the sensor substrate 31 and arranged outside the cavity housing 35 .

Returning to FIG. 1 , the pressure receiving portion 3 b of the pressure detecting portion 3 has a pressure range 100 in which the plurality of pressure contacts 22 press the flow wall 11 while being in contact with the flow wall 11 . is in contact with the flow wall 11 at the position on the opposite side across the . The pressure range 100 of the flow path 10 refers to the range in which the plurality of press contacts 22 move while crushing the inner diameter of the flow path 10 . Note that the pressing range 100 includes a range in which the inner diameter (channel area) of the flow channel 10 is zero (closed range 110 described later) and a range in which the inner diameter of the flow channel 10 is not zero but is crushed. is

In the example shown in FIG. 1, the pressure range 100 of the flow path 10 of the present embodiment extends clockwise around the pressure contact driving portion 23 at the 9 o'clock position 101 where the pressure contact 22 starts pressing the flow wall 11. , to the 3 o'clock position 105 where the pressure contact 22 tends to leave the flow wall 11 . In the pressing range 100, the pressure receiving portion 3b is positioned downstream of the 12 o'clock position 103 where the pressing pressure of the pressure contact 22 against the flow wall 11 is highest (in the example shown in FIG. 1, the 12 o'clock position 103 and 2 o'clock position 104).

A pressing range 100 of the flow path 10 includes a closing range 110 in which the plurality of press contacts 22 move while closing the flow path 10 . Here, closing of the flow path 10 means a state in which the inner diameter of the flow path 10 becomes zero by pressing the pressure contact 22 and the flow of fluid is blocked before and after the pressure contact 22 . In the example shown in FIG. 1, the closing range 110 of the flow path 10 of the present embodiment is 10 in which the inner diameter of the flow path 10 starts to become zero due to the pressing force of the pressure contactor 22 clockwise around the pressure contactor driving portion 23. From the hour position 102 (the state where the inner diameter is almost zero), the pressing pressure of the pressure contactor 22 against the flow wall 11 becomes the highest, and the pressure contactor 22 reaches the 12 o'clock position where the inner diameter of the flow path 10 becomes completely zero. 2 o'clock position 105 (the state where the inner diameter is almost zero) just before the inner diameter of the flow path 10 starts to increase from zero to plus.

In the closing range 110 of the flow path 10, there are a position where the pressure contact 22 closes the flow path 10 (for example, 12 o'clock position 103) and an adjacent position where the pressure contact 22 closes the flow path 10 (for example, 2 o'clock position 103). Positions 104) are formed with both end closures 111 sandwiched between them. The pressure receiving portion 3b extends from the downstream end of the closing area 110 (the 2 o'clock position 104 in the example shown in FIG. 1) toward the upstream side of the flow path 10 in a range corresponding to the forming length P of one of the both end closing portions 111. is in contact with the flow wall 11 at the position of . It should be noted that the formation length P for one of the two-end closing portions 111 corresponds to one pitch of the plurality of press contacts 22 arranged side by side.

FIG. 5 is a developed view in which the channel 10 is linearly extended to explain the movement of the pressure contact 22 according to the first embodiment. In FIG. 5, numerals 1 to 6 are assigned for convenience in order to identify the press contacts 22 that move in the order of (a) to (d) (the same applies to FIG. 6 and FIG. 7 described later). FIG. 6 is a graph showing changes in the internal pressure of the flow path 10 and the output value 3A of the pressure detector 3 according to the movement of the pressure contact 22 according to the first embodiment. Graphs shown in FIGS. 6(a) to 6(d) correspond to movements of the press contact 22 shown in FIGS. 5(a) to 5(d).

As shown in FIG. 5( a ), when the pressure receiving portion 3 b faces the both end closing portions 111 of the flow path 10 , the pressure receiving portion 3 b detects displacement of the flow wall 11 due to the internal pressure of the both end closing portions 111 . That is, the output value 3A of the pressure detection unit 3 corresponds to the internal pressure of the flow path 10 as shown in FIG. 6(a). Further, on the downstream side of the press contact 22 (2 press contact) that closes the downstream end of the both-ends closing portion 111, the pressure is increased due to the pushing out of the fluid.

As shown in FIG. 5B, when the pressure receiving portion 3b faces the pressure contact 22 (the pressure contact 3) across the flow path 10, the pressure receiving portion 3b presses the pressure contact 22 (the pressure contact 3). The displacement of the flow wall 11 due to is detected. That is, the output value 3A of the pressure detection unit 3 becomes higher than the internal pressure of the flow path 10, as shown in FIG. 6(b).

As shown in FIG. 5(c), the pressure contact 22 (the pressure contact 3) facing the pressure receiving portion 3b moves downstream of the pressure receiving portion 3b, but is still positioned in the closed range 110. The portion 3b detects the displacement of the flow wall 11 due to the internal pressure of the both-end closing portion 111. FIG. That is, the output value 3A of the pressure detection unit 3 corresponds to the internal pressure of the flow path 10 as shown in FIG. 6(c).

As shown in FIG. 5(d), when the pressure contact 22 (the pressure contact 3) moves further downstream of the pressure receiving portion 3b and exceeds the downstream end of the closing range 110, the inner diameter of the flow path 10 changes from zero to From the downstream side of the channel 10 where the pressure becomes positive and the pressure is high, the fluid reversely flows toward the inside of the double-end closing portion 111 whose downstream end is open. This reverse flow of fluid is a reverse flow that always occurs due to the principle of operation of peristaltic pumps. At this time, as shown in FIG. 6D, the output value 3A of the pressure detection unit 3 temporarily increases due to the backflow in the flow path 10, but when the backflow settles down, the pump unit 2 corresponds to the internal pressure of the flow path 10 on the downstream side of the .

FIG. 7 is a graph showing changes in the internal pressure of the flow path 10 and the output value 3A of the pressure detection section 3 when clogging occurs in the flow path 10 on the downstream side of the pump section 2 according to the first embodiment. The graphs shown in FIGS. 7(a) to 7(d) correspond to the movement of the press contact 22 shown in FIGS. 5(a) to 5(d).
As shown in FIG. 7, from FIG. 7(a) to FIG. 7(c), the internal pressure of the flow path 10 shown in FIG. 6(a) to FIG. However, when clogging occurs in the flow path 10 on the downstream side of the pump section 2, the internal pressure of the flow path 10 on the downstream side becomes extremely high, so the flow path in FIG. At 10 reverse flows, the level of the output value 3A of the pressure detector 3 increases. In other words, by comparing the output value 3A of the pressure detection section 3 with the normal output value at the timing shown in FIG.

FIG. 8 is a graph showing changes over time in the output of the pressure detection unit 3 (differential pressure sensor) according to the first embodiment. In FIG. 8, the dotted line indicates the normal flow, and the solid line indicates the flow when clogging occurs in the flow path 10 on the downstream side of the pump section 2. As shown in FIG. Further, in FIG. 8, numerals a to d are given for convenience to indicate the output values of the pressure detecting section 3 in FIGS. 5(a) to 5(d) (the same applies to FIG. 9). FIG. 9 is a graph showing changes in output over time when an absolute pressure sensor is used as the pressure detection unit 3 as a comparative example. In FIG. 9, the dotted line indicates the normal flow, and the solid line indicates the flow when clogging occurs in the flow path 10 on the downstream side of the pump section 2. As shown in FIG.

In both cases of FIGS. 8 and 9, if the output when the reverse flow of the fluid occurs at the downstream end of the closed range 110 of d is compared with the normal flow, clogging of the flow path 10 on the downstream side of the pump section 2 is observed. You can detect what happened. Further, the differential pressure sensor shown in FIG. 8 is more significantly different from the normal flow than the absolute pressure sensor shown in FIG. This is because the output of the differential pressure sensor is small if the change in pressure value is large but changes slowly over time, and the output of the differential pressure sensor is small if the change in pressure value is small but changes instantaneously. This is due to the output characteristic of the differential pressure sensor that a large is obtained. That is, since the differential pressure sensor can detect the slope of the pressure change, it becomes easier to detect clogging in the flow path 10 on the downstream side of the pump section 2 than the absolute pressure sensor.

Returning to FIG. 1, the pump abnormality detection system 200 includes a control device 201 that determines whether or not there is an abnormality in the pump 1 with a flow detection function based on a signal output from the pressure detection unit 3 provided in the pump 1 with a flow detection function. I have. For example, the control device 201 determines that there is an abnormality when the output of d shown in FIG. 8 exceeds a predetermined threshold. Further, the control device 201 may determine that the output of d shown in FIG. 8 is abnormal when, for example, the output of b exceeds a predetermined ratio (for example, 50% of b). Alternatively, for example, the control device 201 may determine that there is an abnormality when the output of d shown in FIG. 8 exceeds a predetermined ratio (for example, 110% of d) with respect to the output of d for normal flow. When the control device 201 determines that the pump 1 with a flow detection function is abnormal, it stops the press contact driving section 23, for example.

As described above, in the pump 1 with a flow detection function of the present embodiment, as shown in FIG. It contacts the flow wall 11 of the channel 10 at the position on the opposite side across the 10 . The position where the pressure-receiving portion 3b contacts the flow wall 11 is within a pressing range 100 where the plurality of pressure contacts 22 press the flow wall 11 while contacting the flow wall 11. Instead, a long section for crushing the flow path 10 can be ensured, and a decrease in the suction ability of the pump can be suppressed.

As described above, the pump 1 with a flow detection function according to the present embodiment moves the flow path 10 having the flow wall 11 that is displaced by the pressure change of the fluid flowing inside, and the plurality of press contacts 22 that press against the flow wall 11. As a result, the pressure range 100 in which the pump portion 2 that causes the flow path 10 to perform peristaltic motion and the plurality of pressure contacts 22 press against the flow wall 11 and the position on the opposite side of the pressure contact elements 22 and the flow path 10 are interposed. , a pressure detecting portion 3 having a pressure receiving portion 3 b that contacts the flow wall 11 . Therefore, it is possible to detect the state of flow in the flow path 10 while maintaining the performance of the peristaltic pump.

In addition, in the pump 1 with a flow detection function of the present embodiment, the pressure receiving portion 3b is attached to the flow wall 11 at a position downstream of the flow channel 10 from the position 103 where the pressing pressure of the pressure contact 22 against the flow wall 11 is the highest. in contact. According to this configuration, if clogging occurs in the flow path 10 on the downstream side of the pump section 2, the back flow of the fluid is prevented at the position 103 where the pressing pressure of the pressure contact 22 against the flow wall 11 in the pump section 2 is the highest. Since this can be prevented, the pressure receiving portion 3b can detect the rise in the internal pressure of the flow path 10 due to the reverse flow of the fluid caused by the clogging on the downstream side.

Further, in the pump 1 with a flow detection function of the present embodiment, the pressing range 100 includes a closing range 110 in which the plurality of pressure contacts 22 move while closing the flow path 10. The closing range 110 includes the pressure contacts 22 closes the flow path 10 and a position 104 at which the pressure contact 22 adjacent thereto closes the flow path 10, and a both-end closing portion 111 is formed. The flow wall 11 is in contact with the flow wall 11 at a position within a formation length P corresponding to one end closing portion 111 from the downstream end toward the upstream side of the flow channel 10 .

In the peristaltic pump, the pressure range 100 of the flow path 10 by the plurality of pressure contacts 22 includes a closing range 110 where the pressure of the pressure contacts 22 makes the inner diameter of the flow path 10 zero. , a both-end closing portion 111 sandwiched by two adjacent press contacts 22 is formed. At the downstream end of the closing range 110, the pressure on the flow wall 11 by the pressure contact 22 is weakened, so that the inner diameter of the flow channel 10 changes from zero to positive, and the pressure from the downstream side of the high pressure flow channel 10 is reduced. Backflow of fluid occurs.

Since the pressure-receiving portion 3b is located within the range of the formation length P of one of the both-end closing portions 111 from the downstream end of the closing area 110 toward the upstream side of the flow path 10, such backflow is It is possible to reach the pressure receiving portion 3b without passing through the location where the flow path 10 is closed at the moment of occurrence. As a result, the pressure receiving portion 3b can efficiently detect an increase in the internal pressure of the flow path 10 due to the backflow of the fluid. Further, since the both-ends closing portion 111 is still closed by the pressure contact 22 on the downstream side, the reverse flow of the fluid to the upstream side of the pump portion 2 can be prevented. In addition, if clogging occurs in the flow path 10 on the downstream side of the pump section 2, compared to the normal backflow of the fluid described above, the increase in internal pressure of the flow path 10 due to the backflow of the fluid becomes more pronounced. Clogging of the flow path 10 can be detected by comparing with the reverse flow of the fluid.

In addition, in the pump 1 with a flow detection function of the present embodiment, the pressure detection section 3 includes a cantilever 32 that bends and deforms according to changes in the internal pressure of the pressure receiving section 3b, as shown in FIG. According to this configuration, the cantilever 32 can detect changes in the internal pressure of the pressure receiving portion 3b with high sensitivity. can. Therefore, the pressure receiving part 3b can be installed in the pressure range 100 of the flow path 10 pressed by the pressure contact 22, and the flow condition of the fluid can be detected from the outside of the flow path 10 without lowering the liquid feeding capability of the pump part 2. can. In addition, since the pressure detection unit 3 can also measure the pressure (timing and pressure) of the press contact 22, it is possible to detect the operation status of the pump unit 2 at the same time.

Further, in the pump 1 with a flow detection function of the present embodiment, the pressure detection section 3 includes a cavity housing 35 that forms a differential pressure chamber 30B that communicates with the inside of the pressure receiving section 3b with the cantilever 32 interposed therebetween. According to this configuration, the cantilever 32 is less likely to be affected by the outside air, so displacement of the flow path 10 due to changes in fluid pressure can be detected with high accuracy.

Further, in the pump 1 with a flow detection function of the present embodiment, as shown in FIG. and a conduit 38 . According to this configuration, since the conduit 38 of the pressure receiving portion 3b is in close contact with the flow wall 11 via the elastic body 37, the responsiveness to changes in the internal pressure of the pressure receiving portion 3b due to the displacement of the flow wall 11 is improved. A shape change of the road 10 can be detected with high sensitivity.

Moreover, in the pump 1 with a flow detection function of the present embodiment, the elastic body 37 is softer than the flow wall 11 . According to this configuration, for example, when the flow wall 11 expands, the elastic body 37 softer than the flow wall 11 begins to displace before the flow wall 11 is completely displaced in the thickness direction by the internal pressure of the fluid. The responsiveness of the change in the internal pressure of the pressure receiving portion 3b due to the displacement of the pressure receiving portion 3b is improved, and the shape change of the flow path 10 can be detected with high sensitivity.

Further, the pump abnormality detection system 200 according to the present embodiment detects the flow detection function of the pump 1 based on the signal output from the flow detection function pump 1 and the pressure detection unit 3 provided in the flow detection function pump 1. and a control device 201 that determines the presence or absence of an abnormality. According to this configuration, when an abnormality occurs in the pump unit 2 or the flow path 10, the abnormality can be quickly detected while monitoring the flow state in the flow path 10 while maintaining the performance of the peristaltic pump. This can be reflected in pump control such as operation stop or speed reduction of the pump unit 2 .

(Second embodiment)
Next, a second embodiment of the invention will be described. In the following description, the same reference numerals are given to the same or equivalent configurations as in the above-described embodiment, and the description thereof will be simplified or omitted.

FIG. 10 is a configuration diagram showing the essential parts of the pump 1 with a flow detection function according to the second embodiment.
As shown in FIG. 10 , in the pump 1 with a flow detection function of the second embodiment, the pressure detection section 3 includes an urging section 5 that urges the pressure receiving section 3 b toward the flow wall 11 .

The biasing portion 5 includes a fixed plate 51 and a spring 52 . The fixing plate 51 is arranged on the back side (the cavity housing 35 side) of the detection unit main body 3a. The spring 52 is arranged between the fixed plate 51 and the cavity housing 35 and biases the pressure receiving portion 3b toward the flow wall 11 via the detection portion main body 3a. That is, the biasing portion 5 biases the entire pressure detecting portion 3 toward the flow wall 11 .

According to the second embodiment described above, the pressure from the biasing portion 5 makes it easier for the pressure-receiving portion 3b to maintain close contact with the flow wall 11. Therefore, the change in the internal pressure of the pressure-receiving portion 3b accompanying the displacement of the flow wall 11 , the change in shape of the flow path 10 can be detected with high sensitivity.

Moreover, in the second embodiment, the following modifications can be employed.

FIG. 11 is a configuration diagram showing a modified example of the main part of the pump 1 with a flow detection function according to the second embodiment.
As shown in FIG. 11, the pump 1 with a flow detection function of the second embodiment includes a bellows pipe 53 in which the pressure receiving portion 3b contacts the flow wall 11. As shown in FIG. That is, the pressure-receiving portion 3 b itself has springiness and is pressed against the flow wall 11 . According to this configuration, the bellows pipe 53 of the pressure receiving portion 3b is elastically adhered to the flow wall 11, so that the responsiveness to changes in the internal pressure of the pressure receiving portion 3b due to the displacement of the flow wall 11 is improved. Shape change can be detected with high sensitivity.

FIG. 12 is a configuration diagram showing a modified example of the main part of the pump 1 with a flow detection function according to the second embodiment.
As shown in FIG. 12, the pump 1 with flow detection function of the second embodiment includes a balloon body 54 in which the pressure receiving portion 3b contacts the flow wall 11. As shown in FIG. That is, the pressure-receiving portion 3 b itself has springiness and is pressed against the flow wall 11 . According to this configuration, the balloon body 54 of the pressure receiving portion 3b elastically adheres to the flow wall 11, so that the responsiveness to changes in the internal pressure of the pressure receiving portion 3b accompanying displacement of the flow wall 11 is improved. Shape change can be detected with high sensitivity.

(Third embodiment)
Next, a third embodiment of the invention will be described. In the following description, the same reference numerals are given to the same or equivalent configurations as in the above-described embodiment, and the description thereof will be simplified or omitted.

FIG. 13 is a configuration diagram of the pump 1 with flow detection function and the pump abnormality detection system 200 according to the third embodiment.
As shown in FIG. 13, the pump 1 with a flow detection function of the third embodiment includes a first pressure contact piece 22A and a second pressure contact piece 22B, and the rotational speeds of the first pressure contact piece 22A and the second pressure contact piece 22B are controlled independently. to change. That is, in the third embodiment, the distance between the first pressure contact piece 22A and the second pressure contact piece 22B changes.

The pump unit 2 of the third embodiment includes a pump body 21 formed with a roller housing portion 21a having a circular shape in plan view, a first pressure contact piece 22A and a second pressure contact piece 22B arranged in the roller housing portion 21a, It has a first pressure contact driving section 23A for driving the first pressure contact 22A and a second pressure contact driving section 23B for driving the second pressure contact 22B. In the pump main body 21, the channel 10 is arranged in a substantially Ω-shape in a plan view so as to follow the peripheral wall of the roller accommodating portion 21a. The flow path 10 surrounds the first pressure contact piece 22A and the second pressure contact piece 22B from the outside.

The first press-contact driving portion 23A is arranged in the central portion of the roller accommodating portion 21a and holds the first press-contact 22A via the first arm member 24A. The first press contact driving section 23A includes a rotating device such as a motor (not shown), and revolves the first press contact 22A via the first arm member 24A as indicated by an arrow M1. The first pressure contact piece 22A crushes the flow path 10 housed in the roller housing portion 21a while rotating in a direction opposite to the direction of revolution as indicated by an arrow M2.

The second press-contact driving portion 23B is arranged in the central portion of the roller accommodating portion 21a like the first press-contact driving portion 23A, and holds the second press-contact child 22B via the second arm member 24B. The second press contact driving portion 23B includes a rotating device such as a motor (not shown), and revolves the second press contact 22B via the second arm member 24B as indicated by an arrow M1. The second pressing member 22B crushes the flow path 10 accommodated in the roller accommodating portion 21a while rotating in a direction opposite to the direction of revolution as indicated by an arrow M2.

Specifically, the rotation shaft of the first pressure contactor driving portion 23A is arranged in the central portion of the roller accommodating portion 21a. The rotation axis of the second pressure contact element driving section 23B is coaxial with the rotation axis of the first pressure contact element driving section 23A and is formed in a cylindrical shape surrounding the rotation axis of the first pressure contact element driving section 23A. A first arm member 24A is connected to the upper end of the rotating shaft of the first press contact driving portion 23A. The lower end of the rotating shaft of the first press contact driving portion 23A is led out from the lower end of the cylindrical rotating shaft of the second press contact driving portion 23B and is connected to a first rotating device (motor or the like) not shown.

A second arm member 24B is connected to the upper end of the cylindrical rotating shaft of the second pressure contactor driving portion 23B. The second arm member 24B is arranged below the first arm member 24A. The peripheral surface of the cylindrical rotating shaft of the second pressure contactor driving portion 23B is connected to a second rotating device (motor or the like) via a power transmission mechanism such as a gear train mechanism or a belt mechanism. The first rotating device and the second rotating device are separate rotating devices, each driven under the control of the control device 201 . As a result, the rotational speeds of the first pressure contact piece 22A and the second pressure contact piece 22B can be changed independently. The configuration of this type of pump unit 2 is disclosed in, for example, Japanese Patent Application Laid-Open No. 2020-133458.

The pressure receiving portion 3b of the pressure detecting portion 3 is located in a pressing range 100 in which the plurality of pressure contacts 22 press the flow wall 11 while being in contact with the flow wall 11, and on the opposite side of the plurality of pressure contacts 22 and the flow channel 10. is in contact with the flow wall 11 at the position of . The pressure range 100 of the flow path 10 refers to the range in which the plurality of press contacts 22 move while crushing the inner diameter of the flow path 10 . The pressing range 100 includes a range (closed range 110) in which the inner diameter (channel area) of the flow channel 10 is zero and a range in which the inner diameter of the flow channel 10 is not zero but is collapsed. there is

In the example shown in FIG. 13, the pressing range 100 of the flow path 10 of the third embodiment extends clockwise around the first pressure contact driving portion 23A and the second pressure contact driving portion 23B. The range is from the 7 o'clock position 121 where the second pressure contact member 22B starts pressing the flow wall 11 to the 5 o'clock position 122 where the pressure contact member 22 is about to leave the flow wall 11 .

The pressing range 100 of the channel 10 includes a closing range 110 where the first press contact 22A or the second press contact 22B moves while closing the channel 10. As shown in FIG. In the example shown in FIG. 13, the closing range 110 of the flow path 10 of the third embodiment extends clockwise around the first pressure contact driving portion 23A and the second pressure contact driving portion 23B. From the 8 o'clock position 123 (when the inner diameter is almost zero), the pressure of the first pressure contact piece 22A or the second pressure contact piece 22B is loosened and flow begins. It ranges from zero to the 4 o'clock position 124, just before the inner diameter of the channel 10 begins to become positive (almost zero inner diameter). In the pump section 2 of the third embodiment, the gap between the first pressure contact piece 22A and the second pressure contact piece 22B changes, and the first pressure contact piece 22A and the second pressure contact piece 22B flow at substantially the same pressure. Since it presses against 10, the pressure on channel 10 hardly changes at the location of the pressure contact.

14A and 14B are explanatory diagrams for explaining movements of the first pressure contact piece 22A and the second pressure contact piece 22B according to the third embodiment.
As shown in FIG. 14, the pump section 2 is driven such that the distance between the first press contact 22A and the second press contact 22B gradually narrows toward the downstream end of the closing range 110. As shown in FIG. In other words, the first pressure contact piece 22A and the second pressure contact piece 22B do not always revolve at a uniform or constant speed.

For example, as shown in FIG. 14(a), the first press contact 22A rotates at a predetermined speed within the closing range 110 and is positioned near the downstream end of the closing range 110. As shown in FIG. Then, the second press-contact piece 22B upstream of the first press-contact piece 22A rotates faster than the first press-contact piece 22A and approaches the first press-contact piece 22A.

As shown in FIG. 14B, when the second pressure contact piece 22B approaches the first pressure contact piece 22A, the position where the first pressure contact piece 22A closes the flow path 10 and the second pressure contact piece 22B in the closing range 110 The formation length of the both-ends closing portion 111 sandwiched between the positions for closing the channel 10 is shortened, and the pressure in the channel 10 is increased.

As the second pressure contact piece 22B approaches the first pressure contact piece 22A in this way, the pressure in the flow path 10 rises, and the pressure in the both-end closing portion 111 and the flow path on the downstream side of the first pressure contact piece 22A increase. The pressure in 10 becomes almost equal.

Then, as shown in FIG. 14(c), when the first press contact 22A leaves the downstream end of the closing range 110, the both-ends closing portion 111 is opened, but the pressure in the both-ends closing portion 111 increases to the downstream side. Since the pressure is increased to approximately the same as the pressure in the flow path 10, backflow of the fluid hardly occurs.

When the first press contact 22A leaves the downstream end of the closing range 110, the first press contact 22A begins to accelerate, and this time, the first press contact 22A moves against the second press contact 22B, which is changing to a predetermined speed. getting closer. That is, the positions of the first press contact 22A and the second press contact 22B shown in FIG. 14 are exchanged, and the above-described operations are repeated.

Returning to FIG. 13 , the pressure receiving portion 3 b of the pressure detecting portion 3 is in contact with the flow wall 11 at the half position on the downstream side of the closing range 110 . Here, the half position on the downstream side of the closing range 110 is 12 o'clock which divides the closing range 110 into two in the clockwise direction around the first pressure contact driving portion 23A and the second pressure contact driving portion 23B. The range from position 126 to the 4 o'clock position 124 which is the downstream end of the closed range 110 .

Further, the pressure receiving portion 3b of the pressure detecting portion 3 is positioned within the range of the minimum forming length 120 of the both end closing portions 111 toward the upstream side of the flow path 10 from the downstream end of the closing range 110. in contact. Here, the position within the range of the minimum formation length 120 of the both-ends closing portion 111 means, as shown in FIG. The position within the formed length of both end closures 111 just before the child 22A) leaves the downstream end of the closure region 110. As shown in FIG. In other words, the pressure detecting portion 3 can detect the maximum value of the pressure in the channel 10 by locating the pressure receiving portion 3 b within the range of the minimum forming length 120 of the both-end closing portion 111 .

15 and 16 are graphs showing changes in the output value of the pressure detector 3 according to the movements of the first pressure contactor 22A and the second pressure contactor 22B shown in FIG. Note that the graph shown in FIG. 15 shows changes in the output value when the pressure detection unit 3 includes a sensor for detecting absolute pressure. Also, the graph shown in FIG. 16 shows changes in the output value when the pressure detection unit 3 includes a sensor (see FIG. 2) for detecting differential pressure.

Time Ta in FIGS. 15 and 16 corresponds to the movement of the first press contact 22A and the second press contact 22B shown in FIG. 14(a). A period Tb in FIGS. 15 and 16 corresponds to the movement of the first press contact 22A and the second press contact 22B shown in FIG. 14(b). Time Tc in FIGS. 15 and 16 corresponds to the movements of the first press contact 22A and the second press contact 22B shown in FIG. 14(c).

As shown in FIG. 14A, when the pressure receiving portion 3b faces the first pressure contact member 22A across the flow path 10, the pressure receiving portion 3b detects the displacement of the flow wall 11 due to the pressure of the first pressure contact member 22A. do. That is, the output value of the pressure detector 3 temporarily increases as shown at time Ta in FIGS. 15 and 16 .

As shown in FIG. 14(b), when the first press contact 22A facing the pressure receiving portion 3b moves to the downstream side of the pressure receiving portion 3b, as shown in FIGS. output value temporarily decreases. After that, when the second press-contact piece 22B on the upstream side approaches the first press-contact piece 22A, the output value of the pressure detecting section 3 gradually increases as shown in period Tb in FIGS.

As shown in FIG. 14(c), when the first press contact 22A moves further downstream of the pressure receiving portion 3b and exceeds the downstream end of the closing range 110, the both end closing portions 111 are opened. At this time, as shown at time Tc in FIGS. Since it is equivalent to the internal pressure of 10, there is almost no change after that.

On the other hand, when clogging occurs in the flow path 10 on the downstream side of the pump section 2, the pressure in the flow path 10 on the downstream side is higher than normal due to the clogging of the flow path 10 on the downstream side. , when the downstream side pressure contact (for example, the first pressure contact 22A) leaves the closing area 110, a reverse flow of fluid occurs and the pressure in the flow path 10 changes. Then, the output value of the pressure detection unit 3 rises from the normal time (solid line) as indicated by the dotted line after time Tc in FIGS. 15 and 16 .

In order to detect this abnormality, the control device 201 detects that the signal output from the pressure detection unit 3 after the downstream side pressure contact (for example, the first pressure contact 22A) leaves the downstream end of the closing range 110 is normal. is programmed to determine that clogging has occurred on the downstream side of the flow path 10 when it rises above .

17A and 17B are explanatory diagrams for explaining movements of the first pressure contact piece 22A and the second pressure contact piece 22B when the flow path 10 according to the third embodiment is damaged and fluid leaks. 18 and 19 are graphs showing changes in the output value of the pressure detector 3 according to the movements of the first pressure contactor 22A and the second pressure contactor 22B shown in FIG. Note that the graph shown in FIG. 18 shows changes in the output value when the pressure detection unit 3 includes a sensor for detecting absolute pressure. Also, the graph shown in FIG. 19 shows changes in the output value when the pressure detection unit 3 includes a sensor (see FIG. 2) for detecting differential pressure.

Time Ta in FIGS. 18 and 19 corresponds to the movement of the first press contact 22A and the second press contact 22B shown in FIG. 17(a). A period Tb in FIGS. 18 and 19 corresponds to the movements of the first press contact 22A and the second press contact 22B shown in FIG. 17(b). Time Tc in FIGS. 18 and 19 corresponds to the movements of the first press contact 22A and the second press contact 22B shown in FIG. 17(c).

The example shown in FIG. 17 illustrates the case where the flow wall 11 is damaged and the fluid leaks at a position upstream of the range of the minimum forming length 120 of the both-end closing portions 111 in the closing range 110. there is

Even in this case, as shown in FIG. 17(a), when the pressure receiving portion 3b faces the first pressure contact member 22A across the flow path 10, the pressure receiving portion 3b is pushed by the first pressure contact member 22A. A displacement of the flow wall 11 is detected. That is, the output value of the pressure detector 3 temporarily increases as shown at time Ta in FIGS. 18 and 19 .

However, as shown in FIG. 17(b), the first press contact 22A facing the pressure receiving portion 3b moves to the downstream side of the pressure receiving portion 3b. 18 and 19, the pressure in the flow path 10 hardly rises until the second pressure contact 22B passes over the broken portion of the flow wall 11, After the second pressure contact 22B passes over the broken portion of the flow wall 11, the pressure inside the flow path 10 begins to rise.

Then, as shown in FIG. 17(c), when the first press contact 22A exceeds the downstream end of the closing range 110 and the both-end closing portion 111 is opened, the maximum output value of the pressure detecting portion 3 is As shown at time Tc in FIGS. 18 and 19, it is lower (indicated by dotted line) than at normal times (indicated by solid line).

In order to detect this abnormality, the control device 201 detects the signal output from the pressure detection unit 3 at the timing (time Tc) when the pressure contact on the downstream side (for example, the first pressure contact 22A) leaves the downstream end of the closing range 110. is lower than normal, it is determined that the upstream side of the flow path 10 is leaking.

As described above, according to the pump 1 with a flow detection function of the third embodiment described above, as shown in FIG. The pump section 2 includes a closing range 110 that moves while closing, and the pump section 2 is a first pressure contact driving section that gradually narrows the distance between the first pressure contact 22A and the second pressure contact 22B toward the downstream end of the closing range 110. 23A and a second press contact driving portion 23B.

According to this configuration, in the closing range 110 where the inner diameter of the flow path 10 becomes zero due to the pressing force of the first pressure contact piece 22A and the second pressure contact piece 22B, the first pressure contact piece 22A and the second pressure contact piece 22A and the second pressure contact piece 22A and the second pressure contact piece 22A and the second pressure contact piece move toward the downstream side. The interval 22B gradually narrows, and the pressure inside the flow path 10 increases. As a result, the difference between the pressure in the flow path 10 and the pressure in the flow path 10 on the downstream side when the downstream pressure contact (for example, the first pressure contact 22A) leaves the closed range 110 becomes small. , the occurrence of backflow and pulsation can be suppressed. This reduces noise and increases the detection accuracy of the pressure detection unit 3 .

In addition, in the pump 1 with a flow detection function of the third embodiment, the pressure receiving portion 3b is in contact with the flow wall 11 at the half position on the downstream side of the closing range 110 . When the distance between the first pressure contact 22A and the second pressure contact 22B gradually narrows toward the downstream end of the closing range 110, the pressure contact on the downstream side (for example, the first pressure contact 22A) normally (normally) Although there is almost no change in the pressure in the flow path 10 when the is withdrawn from the closed range 110, if clogging occurs in the flow path 10 on the downstream side of the pump unit 2, clogging of the flow path 10 on the downstream side As a result, the pressure in the flow path 10 on the downstream side is higher than normal, so when the pressure contact piece on the downstream side (for example, the first pressure contact piece 22A) leaves the closing range 110, a backflow of fluid occurs. , the pressure in the channel 10 changes. Pressure change due to backflow of fluid is likely to occur on the downstream side of the closed range 110, so by installing the pressure receiving portion 3b in the downstream half position of the closed range 110, it becomes easier to detect the backflow of the fluid.

In the pump 1 with a flow detection function of the third embodiment, the closing range 110 includes a position where the first pressure contact 22A closes the flow path 10 and a position where the second pressure contact 22B adjacent thereto closes the flow path 10. The pressure receiving portion 3b extends from the downstream end of the closing range 110 toward the upstream side of the flow path 10 in the range of the minimum formation length 120 of the both ends closing section 111. In the inner position, it is in contact with the flow wall 11 . According to this configuration, since the pressure receiving portion 3b is positioned within the range of the minimum forming length 120 of the both end closing portions 111 from the downstream end of the closing range 110 toward the upstream side of the flow path 10, the closing range A maximum value of pressure in channel 10 at 110 can be detected. If the flow path 10 is damaged and fluid leaks, the maximum value of the pressure in the flow path 10 in the closed range 110 will be lower than normal, making it easier to detect an abnormality in the flow path 10 .

Further, the pump abnormality detection system 200 of the third embodiment detects the pump 1 with a flow detection function based on the signals output from the pump 1 with a flow detection function and the pressure detection unit 3 provided in the pump 1 with a flow detection function. and a control device 201 that determines whether or not there is an abnormality in the closing range 110. The control device 201 detects pressure from the pressure detection unit 3 after the pressure contact member (for example, the first pressure contact member 22A) on the downstream side is separated from the downstream end of the closing range 110. If the output signal is higher than normal, it is determined that the flow path 10 is clogged downstream. According to this configuration, when the distance between the first press contact 22A and the second press contact 22B gradually narrows toward the downstream end of the closing range 110, the downstream press contact (for example, When the first pressure contact 22A) leaves the closing range 110, there is almost no change in the pressure in the flow path 10, but if clogging occurs in the flow path 10 on the downstream side of the pump section 2, Due to the clogging of the flow path 10, the pressure inside the flow path 10 rises more than usual. Therefore, when the signal output from the pressure detection unit 3 after the press contact (for example, the first press contact 22A) is separated from the downstream end of the closing range 110 is higher than normal, It can be determined that clogging has occurred on the side.

Further, the pump abnormality detection system 200 of the third embodiment detects the pump 1 with a flow detection function based on the signals output from the pump 1 with a flow detection function and the pressure detection unit 3 provided in the pump 1 with a flow detection function. and a control device 201 that determines whether or not there is an abnormality in the closing range 110. The control device 201 detects from the pressure detection unit 3 at the timing when the pressure contact on the downstream side (for example, the first pressure contact 22A) leaves the downstream end of the closing range 110. It is determined that the upstream side of the flow path 10 is leaking when the output signal is lower than normal. According to this configuration, when the distance between the first pressure contact element 22A and the second pressure contact element 22B gradually narrows toward the downstream end of the closing range 110, the two-end closing portion 111 is minimized under normal conditions. At forming length 120, the pressure in channel 10 is at its maximum. Therefore, if the signal output from the pressure detection unit 3 at the timing when the press contact (for example, the first press contact 22A) leaves the downstream end of the closing range 110 is lower than normal, the flow path 10 can be determined to be leaking.

While the preferred embodiments of the disclosure have been described and described, it is to be understood that they are exemplary of the disclosure and should not be considered limiting. Additions, omissions, substitutions, and other modifications may be made without departing from the scope of the disclosure. Accordingly, the present disclosure should not be considered limited by the foregoing description, but rather by the claims.

For example, in the above embodiment, the Wheatstone bridge circuit 45 is used to detect the change in the resistance value of the cantilever 32, but the present invention is not limited to this case. Any configuration of the detection circuit may be used as long as it can detect the change in the resistance value of the cantilever 32 .
Further, in the above-described embodiment, the configuration in which the detection unit main body 3a includes the cavity housing 35 was exemplified. It does not matter if there is no 35.
Further, the detection unit main body 3a of the pressure detection unit 3 is not limited to the differential pressure sensor provided with the cantilever 32, and may be an absolute pressure sensor, a strain gauge pressed against the flow wall 11, a piezoelectric element, or the like.

Further, for example, in the above-described third embodiment, there are two press contacts whose rotational speeds are independently controlled, but similarly, the interval between adjacent press contacts increases toward the downstream end of the closing range 110. Three or more pressure contacts may be used as long as the pressure contacts are narrowed.
17 is only an example, and the output value of the pressure detection unit 3 shown in FIGS. can vary as appropriate.

DESCRIPTION OF SYMBOLS 1... Pump with a flow detection function 2... Pump part 3... Pressure detection part 3a... Detection part main body 3b... Pressure receiving part 4... Liquid tank 5... Biasing part 10... Flow path 11... Flow wall 21... Pump main body 22... Press contact 22A First pressure contact 22B Second pressure contact 23 Pressure contact drive part 23A First pressure contact drive part 23B Second pressure contact drive part 30A Pressure receiving chamber 30B Differential pressure chamber 32 Cantilever 35 Cavity housing Body 37 Elastic body 38 Tube line 52 Spring 53 Bellows tube 54 Balloon body 100 Pressing range 110 Closing range 111 Both ends closing portion 120 Minimum forming length of both ends closing portion 200 Pump abnormality detection system 201... control device

Claims (16)

a channel having a flow wall that is displaced by a change in pressure of a fluid flowing therein;
a pump unit that causes peristalsis in the flow path by moving a plurality of pressure contacts that are in pressure contact with the flow wall;
a pressure detecting portion having a pressure receiving portion that contacts the flow wall in a pressing range in which the plurality of pressure contact elements press the flow wall and at a position opposite to the plurality of pressure contact elements across the flow channel; A pump with a flow detection function, comprising: 2. The flow according to claim 1, wherein the pressure-receiving portion contacts the flow wall at a position downstream of the flow channel from a position where the pressing pressure of the pressure contact against the flow wall is highest. Pump with detection function. The pressing range includes a closing range in which the plurality of press contacts move while closing the flow path,
Both end closing portions are formed in the closing range sandwiched between a position where the pressure contact closes the flow path and a position where the adjacent pressure contact closes the flow path,
The pressure receiving portion is in contact with the flow wall at a position within a formation length of one of the both end closing portions toward the upstream side of the flow path from the downstream end of the closing range. The pump with a flow detection function according to claim 1 or 2. The pressing range includes a closing range in which the plurality of press contacts move while closing the flow path,
2. The pump with a flow detection function according to claim 1, wherein said pump section includes a press contact driving section that gradually narrows the intervals between said plurality of press contacts toward the downstream end of said closing range. 5. The pump with a flow detection function according to claim 4, wherein the pressure receiving portion contacts the flow wall at a half position on the downstream side of the closing range. Both end closing portions are formed in the closing range sandwiched between a position where the pressure contact closes the flow path and a position where the adjacent pressure contact closes the flow path,
The pressure-receiving portion is characterized in that it contacts the flow wall at a position within the range of the minimum formation length of the both-end closing portions toward the upstream side of the flow path from the downstream end of the closing range. The pump with a flow detection function according to claim 4 or 5. The pump with a flow detection function according to any one of claims 1 to 6, characterized in that the pressure detection section includes a cantilever that bends and deforms according to changes in the internal pressure of the pressure receiving section. 8. The pump with a flow detection function according to claim 7, wherein the pressure detection section has a cavity housing that forms a differential pressure chamber that communicates with the inside of the pressure receiving section with the cantilever interposed therebetween. The pressure receiving portion is
an elastic body in contact with the flow wall;
The pump with a flow detection function according to any one of claims 1 to 8, further comprising: a pipeline pressed against the flow wall via the elastic body. 10. The pump with flow detection function according to claim 9, wherein said elastic body is softer than said flow wall. The pump with a flow detection function according to any one of claims 1 to 8, characterized in that the pressure receiving portion has a bellows pipe that contacts the flow wall. The pump with a flow detection function according to any one of claims 1 to 8, characterized in that the pressure receiving part has a balloon body that contacts the flow wall. The pump with a flow detection function according to any one of claims 1 to 12, wherein the pressure detection section further includes an urging section that urges the pressure receiving section toward the flow wall. . A pump with a flow detection function according to any one of claims 1 to 13;
A pump abnormality detection system, comprising: a control device that determines whether or not there is an abnormality in the pump with flow detection function based on a signal output from a pressure detection unit provided in the pump with flow detection function. A pump with a flow detection function according to any one of claims 4 to 6;
a control device that determines whether or not there is an abnormality in the pump with flow detection function based on a signal output from a pressure detection unit provided in the pump with flow detection function,
In the control device, clogging occurs on the downstream side of the flow path when the signal output from the pressure detection unit after the pressure contact has left the downstream end of the closed range is higher than normal. A pump abnormality detection system characterized by: A pump with a flow detection function according to any one of claims 4 to 6;
a control device that determines whether or not there is an abnormality in the pump with flow detection function based on a signal output from a pressure detection unit provided in the pump with flow detection function,
The control device detects that the upstream side of the flow path leaks when the signal output from the pressure detecting section at the timing when the press contact moves away from the downstream end of the closed range is lower than normal. A pump abnormality detection system characterized by:

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