JP2006230907A - Gripping detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize safety medical apparatus constituted simply and inexpensively by providing a means which constantly monitors the gripping state of a plunger during liquid sending operation of plunging a liquid housed in a container having a liquid sending part at its one end from the other end with a plunger according to control by a control circuit built in the apparatus and which reliably transmits a signal of the gripping state to the control circuit without confusing it with a signal of other medical apparatus. <P>SOLUTION: This simple and inexpensive gripping detector has a mark signal transmission means which electrically generates a mark signal according to the presence/absence of gripping of the the plunger 5 by a gripping mechanism for gripping the plunger and which transmits the generated mark signal to the control circuit by radio. The mark signal includes an ID number with which the apparatus can be specified to discriminate confusion with a signal generated from other medical apparatus. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an improvement of a syringe pusher detection device mounted on a medical device such as a push-out type liquid feeding device or a hemodialysis device that feeds liquid stored in a container in advance with a pusher.

  In general, in a mechanism that pushes liquid stored in a container out of the container with a pusher that moves along the inner cylinder of the container, the pusher is moved while being pressed against the collar provided at the end of the pusher. A method of extruding the applied liquid is adopted. In this case, the container containing the liquid is provided with a liquid feeding section having a small-diameter hole for liquid feeding on the side opposite to the surface pressed by the pusher. In many cases, a tube constituting a liquid supply path is connected to the liquid supply unit, and liquid can be supplied to a desired place by the pressing operation of the pusher. This pressing against the pusher may be manually pushed in if liquid feeding control does not require accuracy, but if the liquid feeding is performed at a constant speed for a long time, it is performed using a mechanical device. .

  As an example of liquid feeding using such a mechanical device, there is a conventional example disclosed in Patent Document 1. This example shows a syringe pump device used for injection of an anticoagulant heparin that prevents blood coagulation in the extracorporeal circuit of the hemodialysis apparatus. In FIG. 2 of Patent Document 1, the flange 19 of the plunger 18 (presser) of the syringe 6 is engaged with the groove 21 provided in the movable arm 20 (holder), and the rack bar 22 and the pinion 23 of the motor 3 are engaged. Thus, the movable arm 20 is moved linearly, and as a result, the operation of pushing out the anticoagulant in the syringe 6 with the plunger 18 is executed.

However, as in the hemodialysis machine shown in this conventional example, when a medical solution is automatically injected into a patient for a long time, if the syringe pusher is removed from the holder holding mechanism for some reason, In such a syringe pump device, it is indispensable to add a function that can always monitor the gripping state of the pusher. However, Patent Document 1 discloses a specific disclosure regarding the function. Not done.
Japanese Utility Model Publication No. 6-13743

  The problem to be solved is that the pusher gripping state is always maintained during the liquid feeding operation in which the liquid contained in the container having the liquid feeding part at one end is pushed out by the pusher from the other end side according to the control by the control circuit incorporated in the apparatus. It is not possible to realize a safe medical device with a simple and inexpensive configuration with a means for monitoring and transmitting the gripping state signal to the control circuit with high reliability without confusion with the signals of other medical devices. Is a point.

  The present invention provides a sign signal transmitting means for electrically generating a sign signal according to whether or not the pusher is gripped by a gripping mechanism for gripping the pusher, and transmitting the generated sign signal to the control circuit by radio waves. The main feature is that the indication signal includes an ID number that can identify the device, and can discriminate confusion from signals generated by other medical devices.

  In the gripping detection device of the present invention, since the indicator signal including the ID number for identifying the device according to the gripping state of the pusher is reliably transmitted to the control circuit wirelessly, the pusher is detached from the gripping mechanism for some reason. If this happens, it will be possible to stop the medical practice of the device and issue an alarm to the administrator such as a doctor or nurse, so that a safe medical device can be detected with a simple and inexpensive configuration. There is an advantage that a device can be provided.

  Realizing a safe medical device by reliably detecting the gripping state of the pusher, that is, the problem of detachment of the pusher while the liquid stored in the container having the liquid feeding part at one end is pushed out from the other end by the pusher This was achieved with a simple and inexpensive configuration without compromising the liquid feeding function of the pusher.

  FIG. 1 is a schematic view of an embodiment of the apparatus of the present invention, in which 1 is a liquid feeding device, 2 is a container containing a liquid, 3 is a container flange, 5 is a pusher, and 6 is a pressing surface of the pusher. Consists of parts, 7 is a holder, 8A and 8B are hook-like hooks, 9A and 9B are pivoting fulcrums of hook-like hooks 8A and 8B, 10 is a spring of elastic biasing means for hook-like hooks 8A and 8B, 11 Release button, 12 is a pusher gripping detector, 13 is a pusher gripping detection chip, 14 is a guide rod coupled to the holder 7, 17 is a drive motor, 20 is a lead screw, and 21 is a nut that engages with the lead screw 20. A carriage that moves the guide rod 14 according to the rotation of the lead screw 20, 23 is a linear encoder that detects the movement position of the carriage 21, and 24 is a clamp that closes the liquid feeding path 25 according to a command. .

  In the figure, the power of the drive motor 17 attached to the support frame 16 is transmitted to the lead screw 20 via the driven gear 19 that meshes with the pinion gear 18 at one end of the pinion gear 18 and the lead screw 20 to rotate the lead screw 20. The carriage 21 containing a nut (not shown) that meshes with the lead screw 20 is linearly moved in accordance with this rotation. The carriage 21 is provided with an optical sensor 22, and the current position of the carriage 22 can be grasped from the slit signal of the linear encoder 23 arranged so as to face the optical sensor 22. The guide bar 14 and the holder 7 are integrally coupled to the carriage 21. When the carriage 21 linearly moves in the arrow S direction, the holder 7 also linearly moves in the arrow S direction at the same time. The carriage 21 also includes a clutch mechanism that can release the engagement between the nut and the lead screw 20 contained therein. When the release button 11 is pressed, the clutch mechanism is activated and the nut and lead screw contained in the carriage 21 are engaged. The 20 meshing is released, and the holder 7 can be moved manually. The drive motor 17 is generally a stepping motor or a DC motor. In addition to an optical type as the linear encoder 23, an optical or magnetic rotary encoder is provided at the other end of the lead screw 20 as an alternative to the linear encoder 23. The same function can be realized even if installed. A similar function can be realized even if such a drive mechanism is composed of a linear motor and a linear encoder.

  The holder 7 is provided with a pusher gripping detection chip 13 that faces the pressing surface of the flange 6 and is capable of linear movement, and a pusher gripping detector 12 having a mechanically movable contact at the tip. The bottom of the holder 7 is provided with a sign signal transmission board 101 on which an RFID chip is mounted, and a transmission / reception board 102 is provided at a position facing the sign signal transmission board 101 on the main body side of the liquid feeding device 1. ing. The sign signal transmission board 101 is provided with a loop antenna around the RFID chip, and a part of the antenna is configured to pass through the movable contact electrode of the pusher gripping detector 12.

  FIG. 2 shows a view of FIG. 1 as viewed from the direction of arrow V. The container 2 and its peripheral members used in the liquid delivery device 1 as described above, and loops in the indication signal transmission board 101 and the transmission / reception board 102 are shown. The relative relationship of antenna patterns is shown. An RFID chip 203 is mounted on the sign signal transmission substrate 101, and an antenna pattern 201 having electrodes 201A and 201B connected to the electrodes of the grip detector 102 is disposed around the RFID chip 203. A transmission / reception substrate 102 having an antenna pattern 202 arranged on a surface exceeding the linear movement range of the antenna pattern 201 is provided. The antenna pattern 202 of the transmission / reception substrate 102 is provided with an electrode 202A and an electrode 202B that enable electrical connection with a control circuit (not shown) that controls the entire liquid delivery device 1, and from this electrode, For example, when radio waves are transmitted at a frequency of 13.56 MHz, power is transmitted to the loop antenna 201 of the sign signal transmission board 101 by electromagnetic induction, and is supplied to the power of the RFID chip 203. The frequency is not limited to 13.56 MHz, and an appropriate frequency such as 135 kHz, 433 kHz, 860 to 930 MHz, or 2.45 GHz can be selected according to the use state of the apparatus.

  A packing 4 that is in close contact with the inner wall of the container 2 is provided on the liquid contact surface side of the pusher 5 inserted into the container 2. When the flange 6 of the pusher 5 is pushed in while supporting the flange 3, the container 2 The liquid stored in the container 2 is fed from the liquid feeding path 25 connected to the liquid feeding section 26. Clamps 24A and 24B are provided in the middle of the liquid supply path 25, and the linear motion pins 27A and 27B incorporated therein are arranged to face each other so as to close the liquid supply path 25 in response to a command signal. . It is obvious that the same purpose can be achieved with one clamp using either the clamp 24A or the clamp 24B as a simple wall.

  FIG. 3 shows a state in which the clamps 24A and 24B are activated and the liquid supply path 25 is closed by the linear motion pins 27A and 27B. When the pusher 5 is pushed in this state, the liquid pressure inside the container 2 increases, but the liquid in the container 2 does not flow beyond the closed position of the liquid feeding path 25. FIGS. 4A, 4B, and 4C show a process of gripping the collar portion 6 of the pusher 5 in the closed state shown in FIG. When the drive motor 17 is rotated according to the operation start command of the liquid delivery device 1, the holder 7 is moved in the direction of arrow M as shown in FIG. At this time, the slanting contact surface formed at the front ends of the hook-like hooks 8A and 8B biased in the closing direction by the spring 10 is designed so as to hit the corner of the hook part 6 in advance. When further moved in the direction, the hook-like hooks 8A and 8B ride on the maximum dimension part of the hook part 6 while resisting the biasing force of the spring 10 by the effect of the oblique contact surface as shown in FIG. . When the holder 7 is further moved in the direction of arrow M, as shown in FIG. 4- (c), hook-like hooks 8A and 8B finally get over the hook part 6, and hook-like hooks 8A and 8B hooking parts are springs. The collar 6 is automatically gripped by the urging force of 10, and preparation for liquid feeding is completed.

  Since the holder 7 is provided with a pusher gripping detection chip 13 which faces the pressing surface of the flange 6 and is capable of linear movement, and a pusher gripping detector 12 having a mechanical movable contact point ahead of it, FIG. ) To FIG. 4- (c), the flange 6 pushes the pusher grip detection chip 13 in the direction opposite to the arrow M direction, pushes the connected detector arm 12A, and finally pusher grip detection. The container 12 is turned on. Therefore, if the output of the pusher gripping detector 12 is monitored by a control circuit provided in the liquid feeding device 1, it is possible to detect whether the holder 7 grips the collar 6 or the pusher 5. It is. In the above description, a detector having a mechanical movable contact is described as an example of a pusher gripping detector. However, in order to eliminate the pusher gripping detection chip, the magnetic proximity switch or the pressing of the collar 6 The gripping state of the pusher 5 can be detected in the same manner even if a load sensor that comes in contact with the surface is used instead.

  After the pusher 5 is automatically gripped in this way, liquid feeding is executed in accordance with a predetermined sequence. After the liquid feeding is completed, the empty container 2 is replaced and the holder is moved to a predetermined position. Although it is necessary to perform the pull-back operation quickly, it is often more convenient to perform manual operation for such a request. Therefore, the gripping mechanism of the present invention is provided with manual release means as shown in FIG. In this figure, when the operator manually pushes the release button 11 in the direction of the arrow P, the oblique contact surface of the inner wall of the release button 11 that contacts the rear ends of the hooks 8A and 8B moves in the direction of the arrow P. The movement of reducing the distance between the rear ends of the hook-shaped hooks 8A and 8B against the urging force of the spring 10 is caused, so that the tip portions of the hook-shaped hooks 8A and 8B rotate about the rotation fulcrums 9A and 9B. As a result, the gripping of the buttocks 6 is released. At this time, as described above, when the release button 11 is pressed, the clutch mechanism is operated to release the engagement between the nut contained in the carriage 21 and the lead screw 20, and the holder 7 can be moved manually. Therefore, if the holder 7 is moved in the direction opposite to the arrow P direction while the release button 11 is pushed in the direction of the arrow P, the holder 7 is quickly moved toward the position at the start of liquid feeding simultaneously with the release of the gripping portion 6. It is possible.

  FIG. 6 is a block diagram showing only the main part as an example of a control circuit used for controlling a liquid delivery device equipped with the gripping mechanism of the present invention. 601 is a microprocessor, 602 is an operation / display panel, 603 is an initial setting input circuit, 604 is an alarm buzzer, 605 is an abnormal display red light, 617 is a motor drive circuit, 622 is a position information processing circuit of the carriage 21, Reference numerals 624A and 624B denote clamp drive circuits for the clamps 24A and 24B, respectively.

  When the operator finishes mounting the container 2 on the liquid delivery device 1 and prepares the liquid delivery path 25 and performs a liquid entry start key input from the operation / display panel 602, the microprocessor 601 first starts the clamp drive circuit 624A. A clamp command is output to 224B and 224B, and the liquid supply path 25 is closed by the clamps 24A and 24B. Thereafter, the microprocessor 601 outputs a rotation command to the motor drive circuit 617, rotates the drive motor 17, moves the carriage 21, and moves the holder 7 in the direction of arrow M in FIG. Further, as in the process shown in FIGS. 4B and 4C, the holder 7 is moved and the pusher 5 is gripped. During this time, the microprocessor 601 monitors the grip detection signal of the pusher gripping detector 12 propagated by radio waves to the transmission / reception substrate 102 via the sign signal transmission substrate 101 and grasps the gripping state with respect to the pusher 5. An encoder signal signal generated from the optical sensor 22 provided in the carriage 21 is acquired via the position information processing circuit 622, so that the current position of the carriage 21 can be accurately grasped.

  FIG. 7 is a diagram showing a connection state between the internal electrode of the pusher gripping detector 12 and the loop antenna 201 in the sign signal transmission board 101. The movement of the detector arm 12A pushed in by the pusher gripping detection chip 13 is interlocked with the movable contact 701 in the pusher gripping detector 12, and when the pusher 5 is gripped, the movable contact 701 becomes the electrode 12NO. The loop antenna 201 in the sign signal transmission board is in a looped state and can communicate with the transmission / reception board 102 in the liquid delivery device 1. At this time, the activated RFID chip 203 continuously transmits a code including the ID number specified to the mounted liquid delivery device 1 and is confused with the transmission signals of other medical devices in the vicinity. Therefore, the gripping state of the pusher can be reliably identified on the control circuit side. As a result, even if the pusher comes off during liquid feeding, the removal can be detected instantaneously by the control circuit, and at the same time the liquid feeding is stopped, a warning is given to the doctor or nurse with the buzzer 604 or red light 605. It is possible to prevent the danger given to the patient.

  As described above, in the present invention, the pusher gripping state is maintained during the liquid feeding operation in which the liquid stored in the container having the liquid feeding part at one end is pushed out by the pusher from the other end side according to the control by the control circuit incorporated in the apparatus. When the pusher is removed from the gripping mechanism for some reason, it has a means to constantly monitor and transmit the signal of the gripping state to the control circuit with high reliability without confusion with the signals of other medical devices. Since it is possible to stop continuation of medical practice in the device and issue an alarm to an administrator such as a doctor or nurse, it is possible to detect a pusher with a simple and inexpensive configuration of a safe medical device. It is very useful in that it can provide a device.

  It can be used for medical devices such as push-out type liquid feeders and syringe pumps that feed the liquid stored in the container in advance with a pusher. It can be applied to applications that require special treatment.

It is explanatory drawing which showed the implementation method of the holding | grip detection apparatus of this invention mounted in the liquid feeding apparatus. Example 1 It is explanatory drawing which showed the relative positional relationship of the arrangement | positioning relationship of a container, a liquid feeding path | route, and a clamp, and a marking signal transmission board | substrate and a transmission / reception board | substrate. It is explanatory drawing which showed the obstruction | occlusion state of the liquid feeding path by a clamp. It is explanatory drawing which showed the automatic holding process with respect to a presser with the liquid feeding apparatus carrying the holding | grip detection apparatus of this invention. It is explanatory drawing which showed the state which released the holding | grip with respect to a pusher with the liquid feeding apparatus carrying the holding | grip detection apparatus of this invention. It is explanatory drawing which showed the main control circuits of the liquid feeding apparatus carrying the holding | grip detection apparatus of this invention with the block diagram. It is explanatory drawing which showed the connection state of the internal electrode of the pusher grip detector of this invention, and the loop antenna in a marking signal transmission board | substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid delivery apparatus 2 Container 5 Pusher 6 Eaves part 7 Holder 8A, 8B Hook hook 10 Spring 11 Release button 12 Pusher grip detector 13 Pusher grip detection chip 14 Guide rod 17 Drive motor 20 Lead screw 21 Carriage 22 Optical Type sensor 23 Linear encoder 24 Clamp 101 Marking signal transmission board 102 Transmission / reception board 201, 202 Loop antenna 203 RFID chip 601 Microprocessor 604 Buzzer 605 Red light 701 Movable contact

Claims (2)

Whether or not the pusher is gripped by a gripping mechanism that grips the pusher in a device that pushes out liquid stored in a container having a liquid feeding part at one end with a pusher from the other end according to control by a control circuit incorporated in the device A gripping detection apparatus comprising: a sign signal transmission means for electrically generating a sign signal corresponding to the signal and transmitting the sign signal to the control circuit by radio waves. The grip detection device according to claim 1, wherein the sign signal includes an ID number for identifying the device.