JP2006052652A - Gear pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gear pump capable of simplifying and miniaturizing a mechanism for transmitting rotary force to a gear and a structure for preventing liquid leak to the outside of a storage body. <P>SOLUTION: A magnet 23 is attached on a drive gear 4 inside of the storage body 31 and a drive coil 24 applying magnetic action on the magnet 23 is arranged outside of the storage body 31. Consequently, rotary force is surely transmitted to the drive gear by electricity carry to the drive coil 24, and the mechanism transmitting rotary force to the drive gear 4 can be easily materialized by only the magnet 23 and the drive coil 24. Also, it is not necessary to make a drive shaft 16 pass through the storage body 13, and the structure preventing liquid leak to the outside of the storage body 31 can be simplified. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a gear pump, for example, a gear pump that conveys a fluid such as a liquid.

  Conventionally, in a gear pump, the shaft of the drive motor passes through the inside and outside of the casing and the tip of the shaft is attached to the gear, or the rotational force of the outer magnet that receives rotational power from the drive motor There is known a magnet coupling structure that transmits to an inner magnet that is directly connected to a gear provided inside (see, for example, Patent Document 1 and Patent Document 2).

  FIG. 3 shows the former gear pump 50, in which the drive shaft 52 of the drive gear 51 and the driven shaft 54 of the driven gear 53 are rotatably supported in a bottomed casing 55. Then, the casing 55 is sealed with a cover plate 57 via the packing 56, and the base end portion of the drive shaft 52 attached to the drive gear 51 is penetrated from the bottom surface of the casing 55 and protrudes to the outside. A driving motor 58 is attached to the end. Here, the casing 55, the packing 56, and the cover plate 57 correspond to a storage body that stores the drive gear 51 and the driven gear 53, which are a plurality of interlocking gears, separated from the outside. Then, by applying a rotational force from the drive motor 58 to the drive shaft 52, the drive gear 51 and the driven gear 53 meshing with the drive gear 51 are rotated in conjunction with each other, and the fluid flows from the inflow path to the discharge path in the casing 55. Conveying.

  Further, in the gear pump 100 of the magnet coupling structure shown in FIG. 4, the drive shaft 102 of the drive gear 101 and the driven shaft 104 of the driven gear 103 are rotatably supported in a bottomed casing 105. In the state, the casing 105 is sealed with the cover plate 107 via the packing 106, and the base end portion of the drive shaft 102 attached to the drive gear 101 is penetrated from the bottom surface of the casing 105 to protrude outside, and the drive shaft 102 An inner magnet 108 is provided at the base end, and an isolation wall 109 is provided around the casing 105 and the inner magnet 108 for isolation from the outside. Here, the casing 105, the packing 106, and the cover plate 107 correspond to a storage body that stores a plurality of interlocking gears such as a drive gear 101 and a driven gear 103 in a state of being isolated from the outside.

Further, outside the isolation wall 109, there are a cup-shaped rotor 111 having an outer magnet 110 on its inner peripheral surface so as to surround the outer periphery of the inner magnet 108, and a driving motor 112 for applying a rotational driving force to the rotor 111. When the rotational driving force from the driving motor 112 is transmitted to the rotor 111 and the outer magnet 110, the inner magnet 108 in the isolation wall 109 is rotated by the magnetic induction based on the rotation of the outer magnet 110, and the driving gear is provided. By rotating the gears 101 and the driven gears 103 engaged therewith in conjunction with each other, the fluid is conveyed from the inflow path to the discharge path in the casing 105.
JP-A-10-122160 JP 2004-72967 A

  However, in the former gear pump 50 having such a configuration, as shown in FIG. 3, the drive shaft 52 penetrates the inside and outside of the casing 53 in such a relationship that the rotational drive force from the drive motor 58 is directly transmitted to the drive shaft 52. For this reason, a structure for preventing liquid leakage such as the packing 61 is always required in the hole 60 through which the drive shaft 52 passes, and there is a problem that the structure for preventing liquid leakage to the driving motor 58 becomes complicated.

  On the other hand, in the gear pump 100 having a magnet coupling structure as shown in FIG. 4, the inside and outside of the casing 105 are completely shut off by the isolation wall 109 disposed around the casing 105, so that the drive motor 112 However, the outer magnet 110 that receives the rotational driving force from the drive motor 112 is provided with the isolation wall 109 interposed therebetween, facing the inner magnet 108 attached to the drive shaft 102. There is a problem that the rotational force transmission structure to the drive gear 101 becomes large and the apparatus cannot be made compact.

  The present invention has been made in consideration of the above points, and provides a gear pump that can simplify the rotational force transmission mechanism to the gear and the structure for preventing liquid leakage to the outside of the housing, and can achieve downsizing. For the purpose.

  In the gear pump according to the first aspect of the present invention, a magnetic body is attached to at least one of the plurality of gears inside the housing body, and a drive source that exerts a magnetic action on the magnetic body is disposed outside the housing body. Thus, the rotational force can be reliably transmitted to the gear to which the magnetic body is attached by energizing the drive source without having to bother passing through the shaft which is the rotation axis of the gear. That is, the rotational force transmission mechanism to the gear here can be easily realized only by the magnetic body and the drive source, and it is not necessary to penetrate the shaft of the gear into and out of the storage body. The structure for preventing liquid leakage can be simplified, and downsizing as a gear pump can be achieved.

  Furthermore, since at least one of the plurality of gears is a shift spur gear, the center distance of each gear can be designed to some extent freely, so that the center distance of each gear can be determined from the outer dimensions of the housing, A plurality of gears can be securely stored in the storage body. Further, since the tooth tip of the shift spur gear is relatively sharp, the gap between the gears can be further filled, and as a result, sufficient pump performance can be obtained.

  In the gear pump according to the second aspect of the present invention, the gear sizes of the driving gear and the driven gear can be made different by changing the tooth tip diameters of the driving gear and the driven gear. The drive gear and the driven gear can be securely stored in the storage body. Further, since the respective rotation speeds of the drive gear and the driven gear can be changed, the amount of fluid that can be sent out as a pump can be changed, and thus a desired flow rate design can be easily performed.

  In the gear pump according to claim 3 of the present invention, the drive gear and the driven gear can have different gear sizes by changing the number of teeth of the drive gear and the driven gear. The drive gear and the driven gear can be reliably stored in the body. Further, since the respective rotation speeds of the drive gear and the driven gear can be changed, the amount of fluid that can be sent out as a pump can be changed, and thus a desired flow rate design can be easily performed.

  In the gear pump according to the fourth aspect of the present invention, the first drive gear and the second drive gear are driven by the first drive source and the second drive source, respectively, so that these gears that are interlocked in the storage body are connected. It can be rotated more reliably.

  In the gear pump according to the fifth aspect of the present invention, by forming the gear and the shaft as an integral part, the number of parts as the gear pump can be further reduced, and the structure of the gear can be simplified.

  In the gear pump according to the first aspect of the present invention, the mechanism for transmitting the rotational force to the gear inside the housing body and the structure for preventing the liquid leakage to the outside of the housing body can be simplified and the size can be reduced.

  In the gear pump according to the second and third aspects of the present invention, the drive gear and the driven gear can be securely stored, and a desired flow rate can be easily designed.

  In the gear pump according to claim 4 of the present invention, the interlocking first drive gear and second drive gear can be driven to rotate more reliably.

  In the gear pump according to the fifth aspect of the present invention, the number of parts as the gear pump can be further reduced, and the structure of the gear can be simplified.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In FIG. 1, reference numeral 1 denotes a gear pump as a whole. The gear pump 1 is configured by connecting a control unit 3 to a flat and thin pump body 2, and energization control of the pump body 2 is performed by the control unit 3. ing.

  As shown in FIG. 2, the pump main body 2 which is a substantial operation portion of the gear pump 1 includes a gear portion 6 including a driving gear 4 and a driven gear 5 meshed with the driving gear 4. It is provided inside a casing 7 that is an outer portion of the main body 2. The casing 7 is formed with an inflow path 8 for allowing a fluid to flow into the casing 7 and a discharge path 9 for discharging the fluid flowing into the casing 7 to the outside.

  As shown in FIG. 1, the casing 7 has a storage portion 12 surrounded by a bottom wall portion 10 and a side wall portion 11 continuous with the bottom wall portion 10, and an opening portion 13 is formed at the top of the storage portion 12. The gear unit 6 is disposed in the storage unit 12 in a rotatable state. Further, a recess 14 that is recessed in a ring shape toward the opening 13 is formed at a portion of the bottom wall 10 where the drive gear 4 is disposed.

  A bearing 15 is provided along the thickness direction of the pump body 2 on the bottom wall 10 of the casing 7 located at the center of the recess 14, and a drive shaft 16 at the center of the drive gear 4 is provided on the bearing 15. Is supported so that the outer periphery of the drive gear 4 and the side wall 11 are in close proximity to each other.

  A driven shaft 17 located in the center of the driven gear 5 and arranged in parallel with the drive shaft 16 is pivotally supported by a bearing portion 18 formed on the bottom portion 10 of the casing 7. And the side wall 11 are arranged in close proximity.

  In a state where the gear portion 6 is stored in the storage portion 12 of the casing 7, the storage portion 12 is sealed by attaching a lid plate 21 as a lid body to the opening portion 13 via the packing 20. A drive gear 4 including a drive shaft 16 and a driven gear 5 including a driven shaft 17 are rotatably supported in the storage portion 12. Here, the side wall portion 11 of the storage portion 12 communicates with the inside of the storage portion 12 at a position where the drive gear 4 and the driven gear 5 are engaged with each other, and the discharge passage 8 and the discharge passage 8 face each other. A route 9 is provided. Here, it is noted that neither the drive shaft 16 nor the driven shaft 17 penetrates and protrudes outside the casing 7. That is, it is not necessary to provide a complicated liquid leakage prevention mechanism in the portion where the drive shaft 16 and the driven shaft 17 are pivotally supported.

  The drive gear 4 includes a plurality of teeth 4B on the outer periphery of a cup-shaped rotating body 4A. A brush yoke of a rotorless motor 22 is provided on the inner peripheral side of the rotating body 4A. A magnet 23 is provided on the circumferential side. The rotating body 4A and the rotor yoke 22, and the rotor yoke 22 and the magnet 23 are all attached and fixed so as not to be separated from each other with a fixing means such as an adhesive interposed.

  On the other hand, the recess 14 formed outside the casing 7 is provided with a driving coil 24 and a stator core 25 around which the driving coil 24 is wound so as to face the magnet 23 inside the casing 7. As a result, a flat brushless motor 26 having a stator composed of the drive coil 24 and the stator core 25 and a rotor composed of the rotor yoke 22 and the magnet 23 is disposed inside and outside the casing 7. Further, the drive coil 24 and the stator core 25 are disposed inside the recess 14 so as not to protrude from the bottom wall portion 10 of the casing 7, so that the brushless motor 26 is incorporated inside and outside the casing 7. In combination with the flat shape of the storage body including 7, the gear pump main body 2 can be made as thin as possible.

  The driven gear 5 that meshes with the drive gear 4 includes a cylindrical rotating body 5A to which a driven shaft 17 is attached at the center thereof, and a plurality of teeth 5B on the outer periphery of the rotating body 5A. Each of the drive gear 4 and the driven gear 5 may be an involute standard spur gear, but at least one gear (for example, the driven gear 5) constituting the gear portion 6 may be a shift spur gear. In this way, in the standard spur gear, the outer diameter of the drive gear 4 and the driven gear 5 and the center distance between the two gears are determined depending on the number of teeth and the module (the length of the teeth 5A and 5B). Although it is difficult to design freely, if it is a shift spur gear, the center distance of both gears can be designed to some extent freely, and the appropriate center distance can be easily determined from the shape of the storage part 12 in the pump body 2 The effect that can be obtained. Further, since the tooth tip of the shift spur gear is relatively sharp, the gap between the drive gear 4 and the driven gear 5 can be further filled.

  The driven gear 5 here has a tooth tip diameter (outer diameter) different from that of the drive gear 4, has a smaller number of teeth than the drive gear 4, and has a tooth tip diameter smaller than that of the drive gear 4. Thus, by making the tooth tip diameters and the number of teeth of the drive gear 4 and the driven gear 5 constituting the gear portion 6 different, the dimensions of the drive gear 4 and the driven gear 5 can be made different sizes, The overall shape of the pump body 2 can be reduced in size. Further, the rotation speed ratio between the drive gear 4 and the driven gear 5 can be easily changed (for example, when the drive gear 4 rotates once, the driven gear 5 is rotated twice), and a more detailed flow rate design is possible as the gear pump 1. become.

  As described above, the casing 7, the packing 20, and the lid plate 21 correspond to the storage body 31 that stores the gear portion 6 including the plurality of interlocking drive gears 4 and driven gears 5 in a sealed state. In addition, the liquid that has entered the container except for the discharge path 9 does not leak. That is, the inside of the casing 7 provided with the drive shaft 16 and the driven shaft 17 that are the gear portion 6 and the shaft, and the outside of the casing 7 provided with the driving coil 24 and the stator core 25 are completely separated by the casing 7. It has a structure.

  The control unit 3 is configured by mounting a plurality of electronic components on a substrate on which a circuit pattern is formed, for example. The control unit 3 and the driving coil 24 are electrically connected by a lead wire 28. By supplying a driving current from the control unit 3 to the driving coil 24 at a predetermined timing, the rotor yoke 22 and the magnet 23 are connected. Is configured such that a rotational driving force is applied to the drive gear 4 to which is attached.

  Next, the effect | action is demonstrated about the said structure. When a drive current is supplied from the control unit 3 to the drive coil 24 at a predetermined timing, the magnet 23 is attached around the drive shaft 16 by the magnetic action of the stator core 25 and the magnet 23 as in the case of the brushless motor. A rotational driving force is directly applied to the rotor yoke 22 and thus to the drive gear 4. As a result, as shown in FIG. 2, the drive gear 4 is rotationally driven in the direction of arrow a, and the driven gear 5 that meshes with the drive gear 4 is rotationally driven in the direction of arrow b.

  When the drive gear 4 and the driven gear 5 start to rotate in the sealed housing portion 12, the drive gear 4 and the driven gear 5 are connected to each other from the inflow path 8 in a direction substantially orthogonal to the axial direction of the drive shaft 16 and the driven shaft 17. The fluid flows into the storage portion 12 so as to be sucked into each tooth gap. Here, the fluid filled in each tooth gap of the drive gear 4 and the driven gear 5 is caused by the bottom wall portion 10 and the side wall portion 11 of the casing 7 as the drive gear 4 and the driven gear 5 rotate. It is confined and carried along the side wall 11 to the discharge path 9 side. Then, due to the engagement of the drive gear 4 and the driven gear 5 on the discharge path 9 side, the fluid in each tooth space is pushed out and sent to the discharge path 9. Thus, the fluid can be conveyed to the outside of the casing 7 through the discharge path 9 in a direction substantially orthogonal to the axial direction of the drive shaft 16 and the driven shaft 17. In addition, if the drive gear 4 and the driven gear 5 interlocked therewith are rotated in the direction opposite to that shown in FIG. 2, the flow of the fluid is also reversed, so that the fluid flows from the discharge path 9 and is discharged to the inflow path 8. become.

  At this time, the drive shaft 16 and the driven shaft 17 do not project through the outside of the casing 7, and the inside and outside of the storage portion 12 are completely isolated only by the casing 7, so that fluid leaks from the inside of the casing 7. Can be reliably prevented.

  Further, by arranging the drive coil 24 and the data core 25 in the recess 14 of the casing 7 so as not to protrude from the bottom wall portion 10 of the casing 7, the thickness of the pump body 2 as a whole can be reduced, and the drive The coil 24 and the stator core 25 can be prevented from being damaged.

  As described above, in this embodiment, the drive gear 4 and the driven gear 5 as the gear portions 6 that are a plurality of gears to be interlocked, and the storage body 31 that hermetically stores the drive gear 4 and the driven gear 5 while being isolated from the outside. And at least one of a plurality of gears (for example, the driven gear 5) in the gear pump 1 including the inflow path 8 through which the fluid flows into the storage body 31 and the discharge path 9 through which the fluid is discharged from the storage body 31. And a magnet 23 as a magnetic body is attached to at least one gear inside the housing 31, that is, the drive gear 4, while a driving coil as a drive source is provided outside the housing 31. 24 is arranged, and is configured to directly apply a rotational driving force to the driving gear 4 to which the magnet 23 is attached by energizing the driving coil 24.

  In this way, the magnet 23 is attached to the drive gear 4 that is at least one gear inside the storage body 31, while only the drive coil 24 that exerts a magnetic action on the magnet 23 is disposed outside the storage body 31. Thus, even if the shaft that is the rotation shaft of the drive gear 4, that is, the drive shaft 16 does not bother the inside and outside of the storage body 31, the drive coil 24 is energized and the rotational force is applied to the drive gear 4 to which the magnet 23 is attached. Can be transmitted reliably. That is, the rotational force transmission mechanism to the drive gear 4 here can be easily realized by only the magnet 23 and the drive coil 24, and it is not necessary to penetrate the drive shaft 16 of the drive gear 4 into and out of the housing 31. Therefore, the structure for preventing liquid leakage to the outside of the storage body 31 can be simplified, and downsizing as the gear pump 1 can be achieved.

  Furthermore, since at least one driven gear 5 constituting the gear portion 6 is a shift spur gear, the center distance between the drive gear 4 and the driven gear 5 can be designed to some extent freely. The center distances of the drive gear 4 and the driven gear 5 can be determined from the outer dimensions, whereby the drive gear 4 and the driven gear 5 that are a plurality of gears can be reliably stored in the casing 7. Further, since the tooth tip of the shift spur gear is relatively sharp, the gap between the drive gear 4 and the driven gear 5 can be further filled, and as a result, sufficient pump performance can be obtained.

  Moreover, you may comprise so that the tooth-tip diameter of the drive gear 4 to which the magnet 23 was attached, and the driven gear 5 which meshes with this drive gear 4 may differ intentionally. Since the gear sizes of the drive gear 4 and the driven gear 5 can be made different by making the tooth diameters of the drive gear 4 and the driven gear 5 different, These drive gear 4 and driven gear 5 can be securely stored. Further, since the rotational speeds of the drive gear 4 and the driven gear 5 can be changed, the amount of fluid that can be sent out as a pump can be changed, and thus a desired flow rate design can be easily performed.

  The number of teeth of the drive gear 4 to which the magnet 23 is attached and the driven gear 5 meshed with the drive gear 4 may be intentionally different. By making the number of teeth of the drive gear 4 and the driven gear 5 different, the drive gear 4 and the driven gear 5 can have different gear sizes. The drive gear 4 and the driven gear 5 can be securely stored. Further, since the rotational speeds of the drive gear 4 and the driven gear 5 can be changed, the amount of fluid that can be sent out as a pump can be changed, and thus a desired flow rate design can be easily performed.

  In this embodiment, the magnet 23 is attached only to the drive gear 4 so that a rotational driving force can be applied from the drive coil 24. However, as another modification, a magnet is attached instead of the driven gear 5. Another second driving gear may be provided, and a rotational driving force may be applied to the magnet of the second driving gear from a second driving coil that is separate from the first driving coil 24. That is, the first driving gear 4 to which the magnet 23 is attached is given a rotational driving force by the first driving coil 24 disposed outside the housing 31, while being interlocked with the first driving gear 4. In addition, a gear portion is provided so that the second drive gear to which a magnet is attached in the same manner as the first drive gear 4 is given a rotational drive force by a second drive coil disposed outside the housing 31. 6 is configured.

  In this way, the first driving gear 4 and the second driving gear are driven separately by the first driving coil 24 and the second driving coil, respectively. The drive gear 4 and the second drive gear can be driven to rotate more reliably.

  Furthermore, the number of parts as the gear pump 1 can be further reduced by forming either the drive gear 4 and the drive shaft 16 as the gear and the shaft, or the driven gear 5 and the driven shaft 17 as an integral part, that is, as an integral part. In addition, the structure of the gear portion 6 can be simplified.

  In addition, this invention is not limited to the said Example, A various deformation | transformation implementation is possible. For example, the case where the gear having the larger tooth tip diameter is used as the drive gear 4 has been described, but the gear having the smaller tooth tip diameter may be used as the drive gear 4. The same effect can be obtained. Moreover, the gear part 6 may be comprised by the drive gear 4 and the driven gear 5 with the same tooth tip diameter, and the gear part 6 may be comprised by three or more some gears. Further, in the above-described embodiment, the case where the driven gear 5 is a shift spur gear has been described. However, the present invention is not limited to this, and the drive gear 4 may be a shift spur gear, or the drive gear 4 and the driven gear. 5 may be a dislocation spur gear.

It is a schematic sectional drawing which shows the whole structure of the gear pump in one preferable Example of this invention. It is a top view of the pump main body of the state which removed the cover plate same as the above. It is a schematic sectional drawing which shows the structure of the conventional gear pump. It is a schematic sectional drawing which shows the structure of another conventional gear pump.

Explanation of symbols

4 Drive gear (gear, first drive gear)
5 Driven gear (gear)
8 Inflow route 9 Discharge route
16 Drive shaft (shaft)
17 Driven shaft (shaft)
23 Magnet
24 Driving coil (drive source, first drive source)
31 Housing

Claims (5)

In a gear pump comprising a plurality of gears to be interlocked, a storage body for hermetically storing the gear in a state of being isolated from the outside, an inflow path for flowing fluid into the storage body, and a discharge path for discharging fluid from the storage body , At least one of the plurality of gears is a shift spur gear, and a magnetic body is attached to at least one of the gears, and a drive source is disposed outside the power source. A gear pump characterized in that a rotational driving force is applied to a gear to which a magnetic body is attached. 2. The gear pump according to claim 1, wherein the gear has different tooth tip diameters between a drive gear to which the magnetic body is attached and a driven gear that meshes with the drive gear. The gear pump according to claim 1, wherein the gear has a different number of teeth between a drive gear to which the magnetic body is attached and a driven gear that meshes with the drive gear. In the gear, the first driving gear to which the magnetic body is attached is given a rotational driving force by the first driving source arranged outside, and the first driving gear is interlocked with the first driving gear. The gear pump according to claim 1, wherein the second drive gear to which a magnetic body is attached in the same manner as the drive gear is configured to receive a rotational driving force from the second drive source arranged outside. The gear pump according to claim 1, wherein the gear is formed integrally with a shaft.

Images