KR100865196B1 - Internal gear type pump with built-in motor and electronic device - Google Patents

Abstract

The motor-integrated internal gear pump 80 includes a pump portion 81 for sucking and discharging a working liquid and a motor portion 82 for driving the pump portion 81. The pump part 81 includes an inner rotor 1 having an outer circumference formed therein, an outer rotor 2 having an inner circumference thereof engaged with an inner rotor 1, an inner rotor 1 and an outer rotor 2 formed therein. ) Are provided with pump casings 3 and 4. The motor part 82 is provided with the rotor 11 and the stator 12 which rotates the rotor 11. The rotor 11 and the outer rotor 2 share a permanent magnet member 112 containing a magnetic powder in resin. Such a structure can be made cheaper and more reliable while maintaining a small and inexpensive function.

Motor integrated internal gear pump, pump section, motor section, stator, rotor

Description

Motor-integrated internal gear pump and electronic device {INTERNAL GEAR TYPE PUMP WITH BUILT-IN MOTOR AND ELECTRONIC DEVICE}

The present invention relates to a motor-integrated internal gear pump and electronic equipment.

Internal gear pumps have been known for a long time as pumps for pumping inhaled liquids against pressure, and are particularly popular as hydraulic source pumps and oil supply pumps.

The internal gear pump consists of a spur gear-shaped inner rotor with teeth formed on its outer circumference and an annular outer rotor with a width almost the same as the inner rotor with its inner circumference as its main active components. . Pump casings having a flat inner surface facing through some gaps on both sides of these rotors are provided to receive both rotors. The number of teeth of the inner rotor is usually less than the number of teeth of the outer rotor, and rotates in the same manner as the power transmission gear in a state where they are engaged with each other. The change in the groove area accompanying the rotation causes the liquid trapped in the groove to be sucked in and discharged to function as a pump. When one of the inner and outer rotors is driven, the other rotates by engagement. The rotation centers of both rotors are shifted, and it is necessary to support the shaft rotatably for each rotor. The pump casing is provided with an opening to a flow passage communicating with the outside called a suction port and a discharge port. The suction port is installed to communicate with this enlarged volume groove, and the discharge port is installed to communicate with this reduced volume groove. As the mold release of the rotor, a circular arc is applied to a part of the outer rotor release and a trocoid curve is applied to the release of the inner rotor.

In the internal gear pump, the inner rotor and the outer rotor are engaged with each other to rotate. Therefore, when one rotor is driven to rotate, the other rotor also rotates. The method of integrating the motor part on the outer circumferential side of the pump part, integrating the rotor of the motor part on the outer rotor, and driving the outer rotor by the motor part can be shorter than the structure in which the pump part and the motor part are connected in the axial direction, thereby making it suitable for miniaturization It can be said.

As an internal gear pump of such a structure, there exists an internal gear pump disclosed by Unexamined-Japanese-Patent No. 2-277983 (patent document 1). In Patent Document 1, an outer gear (outer rotor) in which a rotor (rotor) is mounted on an outer circumference so as to face a stator (stator) mounted inside a motor casing at a predetermined interval in the radial direction thereof and faces it. And an internal gear composed of a combination of inner gears (equivalent to inner rotors) engaged in the outer gear, and both end faces of the internal gear are hermetically closed with a blocking plate, and either of these closing plates It consists of an internal gear pump provided with a suction port and a discharge port communicating with the internal gear. In addition, the closing plate (pump casing) includes a front casing (front casing) and a rear casing (back casing), and a disc-shaped thrust bearing is disposed between both casings and both sides of the internal gear pump, and both sides of the outer gear are disposed. The thrust bearing is supported, and both ends of the support shaft are fixed to both casings, and the inner gear is rotatably supported through the radial bearing on the support shaft, and a part of the handling liquid on the discharge side of the pressurized discharge side is allowed to flow between the rotor and the stator. At the same time, the liquid supply path for lubricating each bearing part and returning to the suction side is provided.

Patent Document 1: Japanese Patent Laid-Open No. 2-277983

However, in the internal gear pump of Patent Document 1, since the outer gear and the rotor are formed by separate members, there is a problem that the size is increased and the cost is increased.

In addition, Patent Document 1 does not disclose materials of the rotor, the outer gear, the inner gear, and the closing plate constituting the internal gear pump, and does not disclose the use of the electronic device. For example, when the internal gear pump is used in an electronic device such as a personal computer or a server, it is required to be suitable for mass production, long life, high accuracy, low sliding friction, low cost, and light weight. do. In addition, since the antifreeze liquid such as ethylene glycol is used in consideration of the storage temperature of the electronic device, as the working liquid flowing in the pump portion in the case of use in an electronic device, the phase property of the internal gear pump and the antifreeze liquid should also be considered. I knew there was a need.

An object of the present invention is to obtain a motor-integrated internal gear pump and an electronic device, which are small, inexpensive and highly reliable, while utilizing an internal gear type function suitable for a high head.

According to a first aspect of the present invention for achieving the above object, there is provided a pump unit for sucking and discharging a working liquid, a motor unit for driving the pump unit, and the pump unit includes an inner rotor having the outer periphery formed therein, and And an outer rotor having an inner rotor that meshes with the inner rotor, and a pump casing for accommodating the inner rotor and the outer rotor, wherein the motor unit includes a rotor and a stator for rotating the rotor. In a motor-integrated internal gear pump, the rotor and the outer rotor are formed in common by a permanent magnet member containing a magnetic powder in a resin.

More preferable specific structural example in this 1st aspect of this invention is as follows.

(1) A common member of the rotor and the outer rotor is formed of a ferrite bond magnet containing ferrite magnet powder while using water or a liquid containing water as a component as a working liquid to be sucked and discharged into the pump section. which.

(2) The joint member of the rotor and the outer rotor is formed of a member having a strong magnetic force on the outer circumferential side and a weak magnetic force on the inner circumferential side, and the stator is provided on the outer circumferential outer side of the shared member.

(3) The antifreeze solution according to (1), wherein water and an organic substance are used as the working fluid.

(4) The said common member was formed in said (1) by the PPS / ferrite bond magnet which contains ferrite magnet powder in PPS resin.

(5) In the above (1), the pump casing is formed by joining two casings each including a first casing and a second casing, and projecting inward to face the first casing and the second casing. Shoulder portions are formed respectively, and on both sides of the outer circumference of the common member, annular projections protruding in the axial direction than the inner portions of the inner circumference are formed. The stator is provided at an outer circumference outer side of the shared member.

(6) The pump casing according to the above (1), wherein the pump casing is made of PPS carbon fiber resin containing carbon fiber in PPS resin or PPS glass fiber resin containing glass fiber in PPS resin.

(7) The said inner rotor was formed in said (1) by PPS carbon fiber resin or POM resin which contained carbon fiber in PPS resin.

(8) The above-mentioned (5), wherein the first casing and the second casing are formed of PPS carbon fiber resin containing carbon fiber in PPS resin.

(9) The sealing portion for (8), wherein the outer peripheral portion of one of the first casing and the second casing extends in the axial direction to form a sealing portion for sealing between the rotor and the stator, and the sealing portion Mounting the stator on the outside.

In addition, a second aspect of the present invention includes a pump portion for sucking and discharging a working liquid, and a motor portion for driving the pump portion, wherein the pump portion is fitted with an inner rotor having an outer circumference formed therein, and a teeth of the inner rotor. The physics includes an outer rotor formed around the inner rotor, a pump casing for accommodating the inner rotor and the outer rotor, and the motor unit includes a rotor and a stator for rotating the rotor. In the gear pump, the rotor is formed of a PPS resin / ferrite bond magnet containing ferrite magnet powder in the PPS resin.

A more preferable specific structural example in this 2nd aspect of this invention is as follows.

(1) The pump casing is formed of PPS carbon fiber resin containing carbon fiber in PPS resin, and the inner rotor is formed of PPS carbon fiber resin containing carbon fiber in PPS resin.

Moreover, the 3rd aspect of this invention is an electronic device which mounts the motor-integrated internal gear pump as described in any one of the above as a liquid circulation source, and uses the antifreeze which consists of water and organic substance as a working fluid.

According to the present invention, it is possible to obtain a motor-integrated internal gear pump and electronic device that is compact, inexpensive, and highly reliable, while utilizing an internal gear type function suitable for high lift.

1 is a longitudinal sectional view of a motor-integrated internal gear pump according to one embodiment of the present invention.

FIG. 2 is a front view showing the left half surface of the pump of FIG.

3 is an exploded perspective view of the pump portion of the pump of FIG.

4 is a cross-sectional view showing a method of joining a casing of the pump of FIG.

5 is a dimensional view of the inner rotor and outer rotor of the pump of FIG.

FIG. 6 is an explanatory diagram of an electronic apparatus having a cooling system having a pump of FIG.

[Description of the code]

1: inner rotor

1a, 2a: this

1b: shaft hole

1c, 2b: end face

2: outer rotor

3: front casing

4: back casing

5: internal shaft

6: sealing part

7: inlet

8: suction port

9: discharge port

9a: communication path

10: discharge port

11: rotor

12: stator

13: cover

14: O ring

16: fitting surface

18: flange portion

21: protrusion

22 shoulder

23: operating room

24: interior space

25: flat inner surface of the front casing

26: flat inner surface of the back casing

27, 28: outer peripheral surface of the shoulder

27a, 28a: fitting holes

29: outer annular portion

31: circuit board

32: power device

33: power line

34: rotating output line

41: welding projection

42: welding groove

43, 44: welding tools

51: bearing part

51a: stepped surface

53: fitting part

60: personal computer

61A: Personal Computer Body

61B: Display Device

61C: Keyboard

62: CPU

63: liquid reservoir

65: heat exchanger

66: heat sink A

67 heat sink B

69: liquid cooling system (cooling system)

80: internal motor gear pump

81: pump part

82: motor unit

83: control unit

112: shared member

EMBODIMENT OF THE INVENTION Hereinafter, the motor-integrated internal gear pump of one Embodiment of this invention, its manufacturing method, and electronic device are demonstrated using FIGS.

First, the entire motor-integrated internal gear pump of the present embodiment will be described with reference to Figs. 1 is a longitudinal sectional view of a motor-integrated internal gear pump 80 of one embodiment of the present invention, FIG. 2 is a front view showing a left half surface of the pump 80 of FIG. 4 is an exploded perspective view of the pump section in the pump 80 of FIG. 1, and FIG. 4 is a cross-sectional view showing a method of joining the casing of the pump 80 of FIG.

The pump 80 includes a pump unit 81 for sucking and discharging the working liquid, a motor unit 82 for driving the pump unit 81, and a control unit 83 for controlling the motor unit 82. It is a motor-integrated internal gear pump provided.

The pump portion 81 includes a resin inner rotor 1, a resin outer rotor 2, a resin front casing (first casing) 3, and a resin back casing (second casing) ( 4) It is comprised including the internal shaft 5 made of metal. The front casing 3 and the back casing 4 are members which form a pump casing, in other words, the pump casing member is composed of two separate member pump casing members. The back casing 4 also includes a seal 6, a flange 18 and a cover 13. The inner shaft 5 constitutes an inner rotor support shaft, and is constituted of a member separate from the front casing 3 or the back casing 4 in this embodiment.

The motor part 82 is comprised with the rotor 11 which consists of permanent magnets, the stator 12, and the sealing part 6, and is comprised. The sealing part 6 is shared by the pump part 81 and the motor part 82.

The inner rotor 1 of the pump portion 81 has a shape similar to that of a spur gear, and forms a tooth 1a that outlines a trocoid curve on its outer circumference. This back surface strictly forms a gradient called a "deformation gradient" which has a slight gradient in the axial direction and assists demolding during injection molding. Moreover, the inner rotor 1 has the axial hole 1b which the inner surface which penetrated to the center in the axial direction is smooth. Both end surfaces 1c of the inner rotor 1 are flat and smoothly finished, and the flat inner surface 25 which is the end face of the shoulder 22 which protrudes inwardly from the front casing 3 and the rear casing 4. The surface which slides between 26) is formed.

The inner rotor 1 is self-lubricating, and is formed of a synthetic resin having a property of swelling deformation and corrosion by water or a solution containing water as negligible levels. Specifically, it is formed of PPS carbon fiber resin containing carbon fiber in PPS (polyphenylene sulfide) resin. Thereby, while having sufficient strength and abrasion resistance as the inner rotor 1, it can be set as the cheap inner rotor 1. P0M (polyacetal) resin may be used in place of PPS carbon fiber resin. P0M has a small frictional resistance and a small sliding resistance, thereby improving pump efficiency. Moreover, since it is ductile as a material, an impact load can be alleviated and the vibration noise by the movement of a rotor is suppressed. In addition, although these materials have absorbency and water permeation, there is no problem because they are used as the inner rotor 1. Moreover, although deformation | transformation by high temperature absorption is caused, the deformation | transformation can be absorbed by making the mold release compensated for that much. At low temperatures, the gap between the rotors 1 and 2 is enlarged. However, when an antifreeze liquid consisting of water and an organic substance is used as the working fluid, the viscosity of the antifreeze liquid also rises, so that the pump efficiency is improved and performance is reduced. You can prevent it.

The outer rotor 2 has an annular inner gear shape having a width substantially the same as that of the inner rotor 1, and has more than one inner rotor 1 having a release formed by an arc or the like. have. The teeth 2a of the outer rotor 2 have a substantially identical cross-sectional shape in the axial direction as a spur gear, but have a slight gradient in the axial direction and are called a "deformation gradient", which assists demolding during injection molding. You may have a gradient. In this case, the same demoulding gradient is also given to the inner rotor 1, the direction of the gradient between the inner rotor 1 and the outer rotor 2 is reversed, and in the direction in which the outer tooth diameter of the inner rotor 1 increases, Both ones and two are engaged so that the diameter of the inner teeth of the outer rotor 2 is also increased. Thereby, the engagement surface of both 1 and 2 can prevent the one-sided contact by the position of an axial direction. Both end faces 2b of the teeth of the outer rotor 2 are finished flat and smooth, and the surface which slides between the front casing 3 and the flat inner surfaces 25 and 26 of the back casing 4 is smooth. And act as a thrust bearing.

The outer rotor 2 has a width substantially the same as that of the inner rotor 1 except for the outer circumference, and the outer side of the outer rotor 1 so that both end faces of the inner rotor 1 and the outer rotor 2 substantially coincide with each other. The rotor 2 is arrange | positioned. In the outer peripheral part of this outer rotor 2, the annular protrusion part 21 which protruded in the axial direction rather than this part (part of this width substantially the same as the inner rotor 1 located in the inner side) is formed. The inner circumference of the protruding portion 21 is formed with a smooth surface, and constitutes a surface that slides between the outer circumferential surfaces 27 and 28 of the shoulder portion 22.

The outer rotor 2 and the inner rotor 1 are fitted to the front casing 3 and the rear casing 4 in an engaged state so as to rotate. In the central shaft hole of the inner rotor 1, a bearing portion of the inner shaft 5 having a smooth outer circumference is fitted with a slight gap, whereby the inner rotor 1 is rotatably rotated on the inner shaft 5. Supported. In addition, since the inner shaft 5 closely fits the front casing 3 and the back casing 4, it does not rotate.

On the outer side of the outer rotor 2, a permanent magnet is integrated as the rotor 11 of the motor portion 82. In the present embodiment, the outer rotor 2 and the rotor 11 are molded as an integral member by resin mixed with magnetic powder. In other words, the rotor 11 of the motor portion 82 and the outer rotor 2 of the pump portion 81 are composed of a common member 112 which is one member made of a permanent magnet member containing magnetic powder. have. As a result, the rotor 11 and the outer rotor 2 can be manufactured in a small size and inexpensively. The rotor 11 is configured to give alternating polarities in the radial direction and to arrange NS poles alternately along the periphery when viewed from the outer circumferential side.

In the present embodiment, the common member 112 is formed of a ferrite bond magnet containing ferrite magnet powder. As a result, even if water or a liquid containing water as a component is used as the working liquid, the magnets are not corroded or rusted, and the manufacturing can be performed at low cost. The common member 112 is formed of a PPS / ferrite bond magnet containing ferrite magnet powder in the PPS resin. As a result, the magnetic characteristics of the motor unit 82 as the rotor 11 are improved, high precision mold release as the pump unit 81 can be molded, and low friction in the portion that functions as a bearing unit. Low wear sliding properties can be obtained, and further, moldability is good, and corrosion resistance in water can also be good.

In the present embodiment, since the magnetic force on the outer circumferential side of the common member 112 is strong and the magnetic force on the inner circumferential side is formed in a cylindrical shape, the stator 12 is provided on the outer circumferential outer side of the shared member 112. It is possible to easily magnetize from the outer periphery, and also to use the ferrite bond magnet, which is generally inexpensive and weak in magnetic force, compared with neodymium magnets, etc., can sufficiently exhibit the function as the rotor 11.

Moreover, in this embodiment, the shoulder part 22 which protruded inward so that the front casing 3 and the back casing 4 may mutually face each other is formed, and the inner periphery is formed in the both sides of the outer peripheral part of the common member 112, respectively. Rather, an annular protrusion 21 protruding in the axial direction is formed, and the annular protrusion 21 is fitted to the outer circumferential surfaces 27 and 28 of the respective shoulder portions 22 of the front casing 3 and the rear casing 4. Since it forms so that the part which functions as the rotor 11 can increase in the axial direction, it also helps to use the ferrite bond magnet which is inexpensive and weak in magnetic force.

It is also conceivable that the outer circumferential portion including the protrusion of the outer rotor 2 shares the outer rotor 2 and the rotor 11 as a composite structure in which the PPS / ferrite bond magnet is a two-sided PPS carbon fiber. In this case, the PPS / ferrite bond magnet, which is difficult to complex molding, is made into a simple cylindrical shape, and the part requiring precision is made of PPS resin, so that there is no hard ferrite lip on the mating surface with the inner rotor 1, resulting in low loss and low wear. do.

The inner shaft 5 has a circular columnar bearing portion 51 which is slightly smaller in outer diameter than the inner diameter of the shaft hole 1b of the inner rotor 1 and slightly longer in the axial direction than this width of the inner rotor 1, The fitting portion 53 extends from both end faces of the bearing portion 51 in both axial directions and has an outer diameter smaller than the outer diameter of the bearing portion 51. Specifically, the axial length of the bearing portion 51 located at the center of the inner shaft 5 is slightly longer (for example, 0.05 to 0.1 mm) than this width of both rotors. Both sides of the bearing portion 51 have a circular columnar fitting portion 53 to be concentric with the bearing portion 51. In addition, the bearing part 51 and the fitting part 53 are names of the part of the internal shaft 5 made from the same metal material, and are integral. Since the inner shaft 5 is made of a metal material, strength and dimensional accuracy are compared with those of the inner rotor 1, the outer rotor 2, the front casing 3 and the back casing 4 made of synthetic resin. Excellent in terms of

The inner shaft 5 also has a function as a structural material connecting the front casing 3 and the back casing 4. The fitting portion 53 is inserted into and fixed to the fitting holes 27a and 28a formed in the flat inner surfaces 25 and 26 of both casings 3 and 4. In this state, the stepped surface (both end surfaces of the bearing portion 51) 51a serving as the boundary between the bearing portion 51 and the fitting portion 53 is in close contact with the flat inner surfaces 25 and 26 of the casing. . Therefore, the length of the bearing part 51 coincides with the distance (interval) between both flat inner surfaces 25 and 26, and both the rotors 1 and 2 are the shafts of the front casing 3 and the rear casing 4; The inner flat surfaces 25 and 26, which are end faces in the direction, are embedded with a slight gap. The fitting hole of the front casing 3 and the back casing 4 is eccentric with respect to the outer peripheral surfaces 27 and 28 of the shoulder part 22 based on the engagement of the both rotors 1 and 2.

The shoulders 22 of the front casing 3 and the back casing 4 are formed by projecting inward to face each other. The outer circumferential surfaces 27 and 28 of the shoulder 22 are fitted to the inner circumferential surface of the protrusion 21 of the outer rotor 2 with a slight gap, and the shoulders of the front casing 3 and the rear casing 4 are fitted. Both sides of the outer rotor 2 are rotatably supported by 22 to act as radial bearings. The shoulders 22 of the front casing 3 and the back casing 4 are in a positional relationship cut out from a part of the same circular column.

The front casing 3 constituting one of the two pump casing members forms an opening called the suction port 8 and the discharge port 10 on its flat inner surface 25. Since the suction port 8 and the discharge port 10 are smaller than this bottom circle of the inner rotor 1, this bottom circle of the inner and outer rotor 2 (the outer rotor 2 is an inner gear, Is larger than the bottom circle diameter]. The suction port 8 faces the operation chamber 23 in which the volume is enlarged, and the discharge port 10 is provided so as to face the operation chamber 23 in which the volume is reduced. In addition, either the ports 8 and 9 are not faced in the operating chamber 23 at the instant of becoming the maximum volume, or the communication chambers have only a slight cross-sectional area.

The suction port 8 and the discharge port 10 communicate with the suction port 7 and the discharge port 9 which are opened to the outside through the L-shaped flow path from the inside of the port groove, respectively. In the middle of the flow path from the discharge port 10 to the discharge port 9, a communication path 9a which is branched and communicates with the internal space 24 facing the outer circumference of the outer rotor 2 is provided. The internal space 24 is a space surrounded by the front casing 3 and the back casing including the sealing portion 6.

The thin cylindrical seal 6 is provided with a small gap (for example, a gap of 1 mm or less) between the outer circumference of the rotor 11, and the rotor 11 is the outer rotor 2. It is rotatable with.

The rear casing 4 constituting one of the two casing members covers the outer side of the outer rotor 2 from a portion of the outer circumference than the portion constituting the flat inner surface 26 and extends in the axial direction. The front part which forms the part 6 and makes the axial rigidity of the sealing part 6 side more flexible than the said flat inner surface 26 side, and comprises one of the said two casing members in the front end side of the sealing part 6 It is joined with the casing 3. That is, the sealing part 6 is a part of the back casing 4, and points out the thin plate part extended in the front direction to the cylindrical shape from the part of outer periphery rather than the part which provided the flat inner surface or the shoulder part.

The front casing 3 and the back casing 4 are in contact with the cylindrical surface called the fitting surface 16, and are fitted with the degree of freedom to move in the axial direction while restraining the radial direction from each other. The fitting surface 16 is comprised from the inner peripheral part of the front-end | tip part of the sealing part 6, and the fitting surface of the outer peripheral part of the outer annular part 29 formed in the inner surface side of the front casing 3. As shown in FIG. A recess is formed in the inner circumference of the tip portion of the sealing portion 6 adjacent to the fitting surface 16, and the O-ring 14 in the recess is inserted, so that the front casing 3 and the rear casing 4 are separated. Confidentiality is maintained. By this structure, the front casing 3 and the back casing 4 can be set as the combined structure in which the airtightness was maintained, maintaining the degree of freedom of an axial direction.

The front casing 3 and the back casing 4 are formed of PPS carbon fiber resin containing carbon fiber in PPS resin. The front casing 3 and the back casing 4 using the PPS carbon fiber resin have a small water absorption, a small deformation due to absorption, a small thermal strain, and a corrosion resistance against the antifreeze and a heat resistance. Since PPS carbon fiber resin is an insulating material, it is effective in preventing short circuits, and has low moisture permeability, and has good sliding mobility in the bearing part. have.

In the vicinity of the outer circumference of the front casing 3, a plurality of welding projections 41 are provided in an annular shape toward the rear side, and the welding projection 41 is inserted into the flange portion 18 of the back casing 4 facing the same. The groove 42 is formed in an annular shape. In this embodiment, as shown in FIG. 4, it is set as the structure which has the inclined surface which forms the front-end | tip of the welding protrusion 41 in inclined surface, and coincides the bottom part of the welding groove 42 with the inclined surface, and the welding tool 43 , 44 are pressed from both sides to the outer circumferential portion of the front casing 3 and the flange portion 18 of the back casing 4, and micro vibration is applied while applying a force to the welding tools 43 and 44. Specifically, the welding tools 43 and 44 are attached to an ultrasonic welding machine, and ultrasonic vibration is given. Thereby, the contact surfaces of both casings 3 and 4 generate | occur | produce and melt | fuse by mutual vibration friction, and fuse | melt each other, and when temperature falls after vibration stop, it reintegrates and integrates. Therefore, the surface which becomes the back surface side of the welding protrusion 41 of the front casing 3, and the surface which becomes the back surface side of the welding groove 42 of the back casing 4 are made into the flat open state, and the welding tools 43 and 44 ) To a shape that can be in close contact.

The groove into which the welding tool 44 on the back casing 4 side is inserted is an annular groove for inserting the stator 12 after welding, and is smaller and simpler than the case where a structure such as a groove for welding is provided. You can do

Until the welding is completed, the contact restrains the axial movement other than the two contacts of the contact between the welding protrusion 41 and the welding groove 42 and the step between the inner shaft 5 and the contact between the flat inner surfaces 25 and 26. Get rid of it. Moreover, the sealing part 6 is thin and is flexible compared with the flat inner surface, the shoulder part, or the welding part vicinity including the structure of the vicinity. By doing so, at the time of welding, the positional relationship of each member is determined in the following order.

First, the fitting part 53 of the inner shaft 5 is inserted in the back casing 4, the inner rotor 1 and the outer rotor 2 are fitted to the inner shaft 5, and the O-ring 14 Fitting the front casing 3 into the rear casing 4. In this state, the welding jig 43, 44 is applied from both sides of the casings 4, 5, and the ultrasonic vibration is applied while pressing with a predetermined force. Thereby, the contact part of the welding protrusion 41 and the welding groove 42 melt | dissolves, and the front casing 3 and the back casing 4 displace in the direction which mutually approaches. In this process, the stepped surface 51a of the inner shaft 5 is in close contact with the flat inner surfaces 25 and 26. When welding is further advanced, the sealing part 6 and the periphery of the back casing 4 elastically deform, and welding progresses to deep. When the excitation is stopped in the state where the force is applied to the welding jig 43 and 44, the weld part which melt | dissolved will fall by temperature, solidify, and a shape is determined in that state. Then, even if the welding jig is removed, the stepped surface 51a of the inner shaft 5 is in close contact with the flat inner surfaces 25 and 26, and the close contact force is the reaction force of the elastic deformation around the sealing portion 6. The state is applied as.

The inner shaft 5 is made of metal, and axial dimension accuracy is more likely to occur than that of the resin casing members 3 and 4. In addition, there is an advantage that the dimension in the width direction can be secured at the central portion immediately adjacent to the teeth of the rotors 1 and 2. In the method of providing the accuracy of the distance between the two flat inner surfaces 25 and 26 only by the dimensional accuracy of the casings 3 and 4 via the outer periphery of the sealing part 6 or the like, without resorting to the accuracy of the inner shaft 5. In comparison, it is very easy to maintain precision. Therefore, according to the structure of this embodiment, the effect which maintains the clearance gap of the back part end surface which has a big influence on pump performance and reliability is high.

Although the welding protrusion 41 is formed in an annular shape, it does not provide one perimeter continuously but makes the shape cut off one part from the circumference as shown in FIG. The reason for this is to limit the area more than one circumference so as to concentrate the pressing force at the time of welding, to ensure the welding, and to arrange the suction flow path and the discharge flow path in the cutout portion, thereby providing the welding tool 43 and these This is to avoid interference with the flow path.

By the action of the fitting surface 16, the positioning accuracy in the radial direction of the two casings can be combined well, and the axial position can be precisely brought into close contact with the inner shaft 5 and the flat inner surfaces 25 and 26. I can keep it. In addition, since the sealing of the inner space 24 is made by the O-ring 14, except for the inlet 8 and the outlet 10, the sealing structure is also simple because there are no holes or fitting surfaces communicating with the outside world. good. Therefore, liquid leakage can also be prevented reliably.

The cover 13 is formed by integral molding in the shape which is folded back from the outer periphery of the front side flange 18 of the sealing part 6 connected from the back casing 4 to the back side. The cover 13 covers the outer circumference of the stator 12 of the motor portion 82, and helps to prevent electric shock, maintain aesthetics, and prevent noise.

At a position outside the sealing portion 6 and facing the rotor 11, a stator 12 wound around a comb-shaped iron core is press-fitted to the outer circumference of the sealing portion 6. The stator 12 is fitted into a circular groove formed between the sealing portion 6 and the cover 13. The motor part 82 which consists of the rotor 11 and the stator 12 is arrange | positioned at the outer peripheral side of the pump part 81 which consists of the inner rotor 1 and the outer rotor 2, and is not arranged in an axial direction. Therefore, the pump 80 can be thinned and downsized.

The control unit 83 is for controlling the motor unit 82 and includes an inverter electronic circuit for driving a DC brushless motor. By installing the motor portion 82 on the outer circumferential side of the pump portion 81 as described above, the control portion 83 is provided on the back side where the suction port 7 or the discharge port 9 of the pump portion 81 is not provided. It becomes possible.

The circuit board 31 is equipped with a power element 32 which is a main electronic component to form an inverter circuit for driving a DC brushless motor. The circuit board 31 is fixed to the back casing 4 by passing through and caulking the projection 45 provided on the back side of the back casing 3 to the hole provided in the center. The power element 32 is in contact with the back casing 4 via the circuit board 31. As a result, heat generated in the inverter circuit can be radiated to the working liquid in the pump portion 81 via the rear casing 4. One end of the winding of the stator 12 is connected to the circuit board 31, and the power line 33 for supplying power from the outside, the rotation output line 34 for transmitting information of the rotational speed in pulses, and their common ground lines. Is connected.

The DC brushless motor is comprised from the motor part 82 which has the rotor 11 and the stator 12 which consist of permanent magnets, and the control part 83 which has an inverter electronic circuit. The structure in which the rotor 11 is inside the thin seal 6 and the stator 12 is outside the seal 6 is called a canned motor. Since the canned motor transmits the rotational power to the inside of the sealing portion 6 called a can by using magnetic force without requiring the shaft sealing or the like, the canned motor is discharged by changing the volume of the operating chamber 23 while isolating the working liquid from the outside. Suitable for the construction of volumetric pumps.

By setting the shape of the pump 80 in the dimensional relationship shown in Fig. 5, the object of the present invention can be more achieved. When the width of the inner rotor 1 and this width of the outer rotor 2 are 1, the outer diameter of the inner rotor is 1.7 to 3.4, the inner diameter of the protrusion of the outer rotor is 2.5 to 5, and the axial length of the protrusion of the outer rotor is It is taken as the dimension of 0.4-0.8.

When the outer diameter of the inner rotor 1 is larger than this range, the ratio of the internal leakage in the end surface gap (reduced by the reverse flow from the side communicating with the discharge port with high pressure to the suction port, to lower the pump performance) is Increases pump performance. Moreover, if it is smaller than this range, the flow velocity in the opening area in communication with the operation chamber and the suction or discharge port increases, increasing the pressure loss, which also lowers the pump performance.

The inner diameter of the protrusion part 21 of the outer rotor 2 needs to be geometrically larger than the outer diameter of the inner rotor 1. At the same time, if it is larger than this range, the frictional force and internal leakage from the bearing surface are increased, resulting in a decrease in pump performance.

If the axial length of the outer rotor protrusion 21 is smaller than this range, the bearing surface pressure may increase and frictional wear may increase, resulting in a decrease in the service life and reliability of the pump. Moreover, when it is larger than this range, it is easy to induce a one-sided contact from the errors, such as a cylinder degree of a bearing surface, concentricity, etc., and it is not a profit.

The rotation speed of the inner rotor may be in the range of 2500 to 5000 revolutions per minute. If the rotational speed is slower than this range, the ratio of the internal leakage to the conveying flow rate increases, resulting in a decrease in pump efficiency. Moreover, if it is faster than this range, the vibration noise which a pump produces will increase.

Next, the operation of the pump 80 will be described with reference to FIGS.

By supplying a direct current 12 V to the power line 33 to supply a current to the motor drive circuit of the control unit 83, the current is sent through the power element 32 to the winding of the stator 12. Thereby, the motor part 82 is started and it controls so that the motor part 82 may rotate at the preset rotational speed. Since the power element 32 outputs the rotation information of the rotor 11 as a pulse from the rotation output line 34, the upper level control apparatus which receives the signal can confirm the operation state of the pump 80. As shown in FIG.

When the rotor 11 of the motor part 82 rotates, the outer rotor 2 integrated with this rotates, and the inner rotor 1 meshed with it rotates as in the general internal gear and rotates together. The working chamber 23 formed in these grooves of the two rotors 1 and 2 enlarges and reduces the volume by the rotation of both rotors 1 and 2. At the lower end in Fig. 2 where the teeth between the inner rotor 1 and the outer rotor 2 are deeply engaged, the volume of the operating chamber 23 is minimized, and the upper end is maximized. Therefore, when the rotor rotates in the counterclockwise direction in Fig. 2, the operating chamber of the right half moves upward while expanding the volume, and the operating chamber of the left half moves downward, reducing the volume. Since all the sliding parts which axially support both rotors 1 and 2 are contained in the working fluid, friction is small and abnormal wear can be prevented.

The working liquid is sucked from the suction port 7 through the suction port 8 into the working chamber 23 which is being expanded. The working chamber 23 with the largest volume is displaced from the outline of the suction port 8 by the rotation of the rotor, completes suction, and is subsequently communicated with the discharge port 10. From this, the volume of the working chamber 23 is changed to reduction, and the working liquid in the working chamber 23 is discharged from the discharge port 10. The discharged working liquid is sent out from the discharge port 9. Since there is a communication path 9a branched in the middle of the discharge flow path, the internal pressure of the internal space 24 is maintained at the discharge pressure.

In this embodiment, since the suction flow path is short, the suction negative pressure is small and cavitation can be prevented. In addition, since a relatively high discharge pressure acts on the inner surface of the sealing portion 6 and acts in a direction in which it is pushed outward, even a thin sealing portion 6 can be prevented from deforming inward and contacting the rotor 11. Can be. At the same time, leakage from the gap as a radial bearing formed in the protruding portion 21 of the outer rotor 2 can be reduced. The reason for this is that the leakage from the gap increases the force toward the outside due to the action of the centrifugal force, but when the internal pressure of the outer space 24, which is the outer circumference, is high, it acts to press and return it.

The heat of the power element 32, which requires cooling due to the heat generated by the operation, passes through the wall surface of the rear casing 4, which is in contact with the circuit board 31, and flows through the internal space 24. It is transferred to the working fluid and released to the outside. Since the working liquid in the inner space 24 is always stirred and sequentially replaced by a small leakage from the radial bearing surface, it can be efficiently carried away with heat. Since the inside of the pump 80 is efficiently cooled in this manner, a heat sink or a cooling fan for cooling the power element 32 is not required. In addition, the heat generated from the motor loss generated in the rotor 11 and the stator 12 is also efficiently carried away in the same manner, and an abnormal temperature rise can be prevented.

Next, an electronic device having the pump 80 described above will be described with reference to FIG. Fig. 6 is a perspective view showing the entire configuration of a personal computer in a state in which the main body of the personal computer is arranged vertically, and the electronic device shown in Fig. 4 is an example of a desktop personal computer.

The personal computer 60 includes a personal computer main body 61A, a display device 61B, and a keyboard 61C. The liquid cooling system 69 is incorporated in the personal computer main body 61A together with the CPU (central computing unit) 62, and the liquid storage unit 63, the pump 80, the heat exchanger 65, Each element of the heat sink A 66 and the heat sink B 67 is constituted by a closed loop system in which pipes are connected in this order. The purpose of the installation of the liquid cooling system 69 is to mainly transport the heat generated by the CPU 62 incorporated in the personal computer main body 61A to the outside, and to maintain the temperature rise of the CPU 62 below a prescribed value. . The liquid cooling system 69 which uses water or a liquid mainly composed of water, for example, water and an antifreeze composed of organic matter (such as ethylene glycol) has a higher heat carrying capacity and a higher noise level than the air cooling method. Since it is small, it is suitable for cooling the CPU 62 with a large amount of heat generation.

The liquid to be transferred (operating liquid) and air are enclosed in the liquid storage part 63. The liquid reservoir 63 and the pump 80 are juxtaposed, and the outlet of the liquid reservoir 63 and the suction port of the pump 80 communicate with each other by a conduit. The heat exchanger 65 is provided in close contact with the heat dissipation surface of the CPU 62 via thermally conductive grease. The discharge port of the pump 80 and the inlet of the heat exchanger 65 communicate with each other by a pipe line. The heat exchanger 65 communicates with the heat sink A 66 by a conduit, the heat sink A 66 communicates with the heat sink B 67 via a conduit, and the heat sink B 67 connects with the liquid reservoir 63. Communicating through. The heat sink A 66 and the heat sink B 67 are provided so as to radiate heat from the other surface of the personal computer main body 61A to the outside.

In the pump 80, the power line 33 is arrange | positioned from the DC 12V power supply normally provided in the personal computer 60, and the rotation output line 34 is connected to the electronic circuit of the personal computer 60 which is an upper control apparatus. It is.

The operation of this liquid cooling system 69 will be described. As electric power is sent with the personal computer 60 being activated, the pump 80 is started and the liquid to be pumped starts circulation. The conveyed liquid is sucked into the pump 80 from the liquid storage part 63, pressurized by the pump 80, and sent to the heat exchanger 65. The conveyed liquid sent from the pump 80 to the heat exchanger 65 absorbs heat generated by the CPU 62 and the liquid temperature rises. In addition, the conveyed liquid is heat exchanged with the outside air (heat radiates to the outside air) in the next heat sink A 66 and the heat sink B 67, and returns to the liquid storage part 63 after the liquid temperature is lowered. Hereinafter, this is repeated and cooling of the CPU 62 is continuously performed.

Since the pump 80 is an internal gear type which is a kind of volumetric pump, it has the ability to make the suction port a negative pressure even when starting in a dry state (no liquid condition). Therefore, even if it passes through the pipeline higher than the liquid level inside the liquid storage part 63, or even if the pump 80 is higher than the liquid level, it has the ability to suck | suck liquid with no priming water. In addition, since the internal gear pump 80 has a high pressurization capacity as compared with a centrifugal pump or the like, it is also applicable to a condition in which pressure loss passing through the heat exchanger 65 or the heat sinks 66 and 67 increases. In particular, when the heat generation density of the CPU 62 is high, it is necessary to bend and lengthen the flow path inside the heat exchanger 65 in order to enlarge the heat exchange area, and in the liquid cooling system using a centrifugal pump or the like, the passage pressure Although the loss increases, application becomes difficult, but it can respond to this in the liquid cooling system 69 of this embodiment.

In the liquid cooling system 69 of the present embodiment, since the liquid temperature is lowered via the heat sinks 66 and 67 immediately after the outlet of the heat exchanger 65 at which the transported liquid becomes the highest temperature, the liquid reservoir 63 or the pump The temperature of 80 is kept relatively low. Therefore, the internal parts of the pump 80, etc. are easier to ensure reliability than a high temperature environment.

As a result of the operation of the liquid cooling system 69, the temperature of each part in which the liquid circulates is determined, but they are monitored by a temperature sensor (not shown). When the lack of cooling capacity is confirmed by the temperature rise beyond the prescribed level, the increase in the rotational speed of the pump 80 is instructed to prevent excessive temperature in advance. On the contrary, when the cooling is excessive, the rotational speed is suppressed. The rotational output transmitted by the pump 80 is always monitored, and when the rotational output is interrupted and the liquid temperature change is abnormal, the pump 80 is determined to be a failure, and the personal computer 60 proceeds to an emergency operation. In an emergency operation, a hardware damage is prevented after a minimum operation such as a decrease in CPU speed or preservation of a program during operation.

Claims (13)

A pump portion for sucking and discharging the working liquid, and a motor portion for driving the pump portion, The pump unit includes an inner rotor with teeth formed on its outer circumference, an outer rotor with its inner circumference formed in engagement with the teeth of the inner rotor, a pump casing for accommodating the inner rotor and the outer rotor, In the motor-integrated internal gear pump comprising the motor unit and a stator for rotating the rotor, A motor-integrated internal gear pump comprising: a permanent magnet member containing magnet powder in resin; the rotor and the outer rotor are formed in common. 2. The ferrite bond magnet according to claim 1, wherein a liquid containing water or water as a component is used as a working liquid for inhaling and discharging the pump unit, and a ferrite bond magnet containing ferrite magnet powder is used for sharing the rotor with the outer rotor. A motor-integrated internal gear pump comprising a member. The joint member of the rotor and the outer rotor is formed of a member having a strong magnetic force on the outer circumferential side and a weak magnetic force on the inner circumferential side, and the stator is provided on the outer circumferential outer side of the shared member. Motor integrated internal gear pump, characterized in that. 3. The motor-integrated internal gear pump according to claim 2, wherein an antifreeze comprising water and organic matter is used as the working fluid. 3. The motor-integrated internal gear pump according to claim 2, wherein the common member is formed of a PPS / ferrite bond magnet containing ferrite magnet powder in PPS resin. The said casing is comprised by combining two casings which consist of a 1st casing and a 2nd casing, respectively, The shoulder part which protruded inward so that the said 1st casing and the 2nd casing may face each other, respectively is formed. And annular projections projecting in the axial direction from the inner peripheral portions of the outer circumferential portion of the common member, and fitting the annular projections to outer peripheral surfaces of the respective shoulder portions of the first casing and the second casing. And the stator is provided on an outer circumference outer side of the shared member. The motor-integrated internal gear pump according to claim 2, wherein the pump casing is formed of PPS carbon fiber resin containing carbon fiber in PPS resin or PPS glass fiber resin containing glass fiber in PPS resin. The motor-integrated internal gear pump according to claim 2, wherein the inner rotor is formed of PPS carbon fiber resin or POM resin containing carbon fiber in PPS resin. The motor-integrated internal gear pump according to claim 6, wherein the first casing and the second casing are formed of a PPS carbon fiber resin containing carbon fibers in the PPS resin. 10. The method of claim 9, wherein the outer peripheral portion of any one of the first casing and the second casing extends in the axial direction to form a seal for sealing between the rotor and the stator, the stator outside the seal Motor-integrated internal gear pump, characterized in that the mounting. A pump portion for sucking and discharging the working liquid, and a motor portion for driving the pump portion, The pump unit includes an inner rotor formed therein on the outer circumference, an outer rotor formed around the inner rotor engaging with the inner rotor, and a pump casing for accommodating the inner rotor and the outer rotor, In the motor unit, an internal gear pump comprising a rotor and a stator for rotating the rotor, A motor-integrated internal gear pump comprising the rotor formed of a PPS resin / ferrite bond magnet containing ferrite magnet powder in PPS resin. 12. The motor according to claim 11, wherein the pump casing is formed of PPS carbon fiber resin containing carbon fiber in PPS resin, and the inner rotor is formed of PPS carbon fiber resin containing carbon fiber in PPS resin. Integral internal gear pump. An electronic apparatus comprising the motor-integrated internal gear pump according to any one of claims 1 to 12 as a liquid circulation source, and an antifreeze made of water and organic materials as the working fluid.

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