JP2021148056A - Oil pump device - Google Patents

Abstract

To improve workability at assembling.SOLUTION: An oil pump device 60 comprises: a case body 61; an inscription gear pump part 62 arranged in an accommodation space S; a drive shaft 70 arranged while penetrating the case body 61 from the outside of the case body 61 up to the accommodation space S, and rotating an inner rotor 67 by being rotated; and a drive gear 71 integrally arranged at the drive shaft 70 at the outside of the case body 61, and transmitting the inputted rotation to the drive shaft 70. The inner rotor 67 is positioned in an axial direction of the drive shaft 70 with respect to the case body 61, and arranged while being rotatably supported. The inner rotor 67 and the drive shaft 70 are integrally arranged by interference-fitting. The drive gear 71 is arranged while having a gap G between the case body 61 and itself in an axial direction.SELECTED DRAWING: Figure 2

Description

This technique relates to an oil pump device applied to generate oil in a vehicle.

Conventionally, as an oil pump device mounted on a vehicle, a configuration in which an inner rotor (pump gear) and an outer rotor are provided in a pump body and a drive shaft that rotates integrally with the inner rotor is rotated to generate flood control has been known. There is. Further, in such an oil pump device, for example, a drive gear (rotation transmission member) that rotates integrally with the drive shaft is provided outside the pump body, and the drive gear is engaged with the drive-rotating gear of the vehicle to drive the vehicle. Is known (see Patent Document 1).

When assembling an oil pump device having such a drive gear, the drive shaft and the drive gear are integrally formed by, for example, insert molding, and the drive shaft is passed through the pump body and the inner rotor. Then, a pin member orthogonal to the axial direction is passed through the tip of the drive shaft penetrating the inner rotor, the drive shaft and the drive gear are pulled out in a direction away from the pump body, and the pin member is inserted into the groove on the side of the inner rotor. Engage. Further, a pump cover is attached to the pump body to close the pump body. As a result, even if the drive shaft tries to move in the axial direction, the movement is restricted by the pin member coming into contact with the inner rotor and the pump cover.

Japanese Unexamined Patent Publication No. 2006-348920

However, in the oil pump device described in Patent Document 1, when assembling, the drive shaft is penetrated against the pump body, the drive gear is abutted against the pump body, and the pin member is inserted into the tip end portion of the drive shaft. Then, there are a number of work steps in which the drive shaft is pulled out in the opposite direction and the pin member is engaged with the groove of the inner rotor. Therefore, the workability when assembling the oil pump device was poor.

Therefore, it is an object of the present invention to provide an oil pump device capable of improving workability at the time of assembly.

This oil pump device is formed by fastening a first member and a second member, and has a case body having an accommodating space inside and a pump gear that generates hydraulic pressure by rotation, and is provided in the accommodating space. A hydraulic pressure generating unit, a drive shaft provided through the case body from the outside of the case body to the accommodation space and rotating the pump gear by being rotated, and a drive shaft integrated with the drive shaft outside the case body. The pump gear is positioned in the axial direction of the drive shaft with respect to the case body, and is rotatably supported. The pump gear and the drive shaft are integrally provided by tightening and fitting, and the rotation transmission member is arranged with a gap between the pump gear and the case body in the axial direction.

According to this oil pump device, workability at the time of assembly can be improved.

The cross-sectional view which shows the outline of the drive device for a hybrid vehicle which concerns on embodiment. The cross-sectional view which shows the oil pump device which concerns on embodiment.

Hereinafter, embodiments of the oil pump device according to the present disclosure will be described with reference to FIGS. 1 and 2. In the present embodiment, it is assumed that the oil pump device is applied to the hybrid vehicle drive device 1.

[Drive device for hybrid vehicles]
First, the configuration of the hybrid vehicle drive device 1 will be described with reference to FIG. The hybrid vehicle drive device 1 includes four axial centers C1 to C4 in the casing 2. An input shaft 11, a planetary gear device 12, and a first rotor shaft 13 of the first electric motor MG1 are rotatably supported on the first shaft center C1. A counter shaft 21 is rotatably arranged on the second axis C2. A power transmission shaft 31 and a second rotor shaft 32 of the second electric motor MG2 are rotatably supported on the third shaft center C3. Further, a differential ring gear 41 is rotatably supported on the fourth axis C4. Further, the hybrid vehicle drive device 1 includes an oil pump device 60.

The planetary gear device 12 constitutes a power distribution mechanism together with a damper device (not shown). The damper device absorbs torque fluctuations transmitted from an internal combustion engine (not shown). A composite gear shaft 14 on which a counter drive gear 15 described later is formed is provided on the outer peripheral side of the planetary gear device 12.

The first electric motor MG1 is arranged on the outer peripheral side of the first rotor shaft 13. The first electric motor MG1 includes a stator 51, a rotor 52, and a coil end 53. The rotor 52 is fixed to the first rotor shaft 13 so as not to rotate relative to each other.

The counter shaft 21 is provided with a counter driven gear 22 and a differential drive gear 23. The counter driven gear 22 meshes with the counter drive gear 15 of the composite gear shaft 14 and the reduction gear 33 described later. The differential drive gear 23 meshes with the differential ring gear 41. The counter-driven gear 22 and the differential drive gear 23, and the counter drive gear 15, the reduction gear 33, and the differential ring gear 41 that mesh with each other are all formed on the oblique teeth.

The power transmission shaft 31 is formed with a reduction gear 33 that meshes with the counter driven gear 22. The second motor MG2 is arranged on the outer peripheral side of the second rotor shaft 32. The second motor MG2 includes a stator 54, a rotor 55, and a coil end 56. The rotor 55 is fixed to the second rotor shaft 32 so as not to rotate relative to each other.

Here, the differential drive gear 23 is shown as a separate figure in which the first axis C1 to the fourth axis C4 are not actually arranged in a straight line as shown in FIG. Because. Actually, the third axis C3 is located most vertically above, and the fourth axis C4 is located most vertically below.

[Oil pump device]
Next, the configuration of the oil pump device 60 will be described with reference to FIG. In the present embodiment, the oil pump device 60 is an oil pump device for supplying lubricating oil to the hybrid vehicle drive device 1 (see FIG. 1), and is driven by the rotation of the differential ring gear 41.

The oil pump device 60 includes a case body 61 having an accommodation space S inside, and an inscribed gear pump unit 62 which is an example of a hydraulic pressure generating unit provided in the accommodation space S. The case body 61 is formed by fastening the pump body (first member) 63 having the accommodation space S and the pump cover (second member) 64 that closes the accommodation space S of the pump body 63 with bolts 65. ing. Further, the pump cover 64 is fastened to the casing 2 by bolts 66.

The inscribed gear pump unit 62 has an inner rotor 67 (drive gear) and an outer rotor 68 (driven gear), which are examples of pump gears that generate flood control by rotation. The inner rotor 67 has a plurality of external teeth. The outer rotor 68 has a plurality of internal teeth that mesh with a plurality of external teeth of the inner rotor 67, and is provided eccentrically with respect to the inner rotor 67. The inner rotor 67 and the outer rotor 68 are provided on the case body 61 so as to be positioned in the axial direction of the drive shaft 70, which will be described later, and rotatably supported. As the inscribed gear pump unit 62, a known inscribed gear pump can be applied.

Further, the oil pump device 60 has a drive shaft 70 that drives the inscribed gear pump unit 62, and a drive gear 71 that is an example of a rotation transmission member integrally provided on the drive shaft 70. The drive shaft 70 is provided so as to penetrate the case body 61 from the outside of the case body 61 to the accommodation space S, and is provided so as to penetrate the pump cover 64 in the present embodiment. The tip end side (right side in FIG. 2) of the drive shaft 70 penetrates the pump body 63. An inner rotor 67 is integrally provided on the drive shaft 70 by tightening and fitting, and the inner rotor 67 is rotated by rotating the drive shaft 70. In the present embodiment, the pump body 63, the pump cover 64, and the drive gear 71 are arranged in this order in the axial direction.

The drive gear 71 is integrally provided on the drive shaft 70 outside the case body 61, and transmits the input rotation to the drive shaft 70. In the present embodiment, the drive gear 71 is provided so as to mesh with the differential ring gear 41 which is an example of a rotating member that transmits the drive rotation for traveling the vehicle. However, the drive gear 71 is not limited to the configuration that meshes with the differential ring gear 41, and may be another rotating member that transmits the drive rotation that causes the vehicle to travel.

[Drive shaft]
Next, the configuration of the drive shaft 70 will be described in detail. In the present embodiment, the drive shaft 70 is made of metal, the drive gear 71 is made of resin containing glass fiber, for example, and the drive shaft 70 and the drive gear 71 are integrally formed by insert molding. The oil pump device 60 here is a relatively small output oil pump device for outputting lubricating oil, and the resin constituting the drive gear 71 is reinforced with glass fiber, so that the drive gear Even if 71 is made of resin, sufficient strength can be secured. The drive shaft 70 and the inner rotor 67 are integrally provided by press-fitting the drive shaft 70 from the drive gear 71 side (rotation transmission member side) in the axial direction, that is, from the left side to the right side in FIG. There is. Further, in the drive shaft 70, the end surface 70a on the drive gear 71 side in the axial direction is exposed from the drive gear 71. As a result, when the drive shaft 70 is press-fitted into the inner rotor 67, the pressing portion of the pressing device, a jig, or the like can be brought into contact with the end surface 70a of the drive shaft 70 to receive the pressing force for press-fitting.

The drive shaft 70 has a large-diameter portion 72 in which the drive gear 71 is integrally molded on the drive gear 71 side and a small-diameter portion 73 in which the inner rotor 67 is tightly fitted on the inner rotor 67 side in the axial direction. .. The tip of the large diameter portion 72 is further expanded in diameter so that the integrally molded drive gear 71 is positioned so as not to come off in the axial direction. The boundary between the large diameter portion 72 and the small diameter portion 73 is a step portion 74. The inner rotor 67 is tightly fitted to the fitting portion 75 of the small diameter portion 73 in a state of being in contact with the step portion 74. That is, the drive shaft 70 has a step portion 74 having a diameter larger than that of the fitting portion 75 on the drive gear 71 side in the axial direction of the fitting portion 75 that is tightly fitted to the inner rotor 67.

When the small diameter portion 73 of the drive shaft 70 is press-fitted into the inner rotor 67, the stepped portion 74 comes into contact with the inner rotor 67, and the drive shaft 70 is positioned. Here, the positional relationship between the step portion 74 and the drive gear 71 in the axial direction is such that the drive gear 71 is axially positioned by positioning the drive shaft 70 in which the step portion 74 is tightly fitted to the fitting portion 75 in the axial direction. It is arranged with a gap G between it and the case body 61. In the present embodiment, the boss portion 71a of the drive gear 71 and the boss portion 64a of the pump cover 64 face each other in the axial direction, and are closest to each other between the drive gear 71 and the pump cover 64, but each boss. A gap G is provided between the portions 71a and 64a so that they do not come into direct contact with each other.

Here, as a comparative example, a case where the boss portions 71a and 64a come into contact with each other will be considered. In this case, for example, if the drive gear 71 is made of resin containing glass fiber and the pump cover 64 is made of aluminum, the drive gear 71 comes into contact with the pump cover 64 while rotating, so that the pump cover 64 is moved by the drive gear 71. There is a risk of wear. On the other hand, in the oil pump device 60 of the present embodiment, a gap G is provided between the boss portion 71a of the drive gear 71 and the boss portion 64a of the pump cover 64 so as not to come into direct contact with each other. Therefore, even if the drive gear 71 is made of resin containing glass fiber, the wear of the pump cover 64 can be reduced. Here, the drive gear 71 is made of a resin containing glass fiber, but the present invention is not limited to this, and for example, it may be made of a resin containing carbon fiber, or if the strength is sufficient, the fiber may be contained. It does not have to be.

[Operation of oil pump device]
Next, the operation of the oil pump device 60 will be described. When the differential ring gear 41 rotates as the vehicle travels, the drive gear 71 rotates. The rotation of the drive gear 71 causes the drive shaft 70 to rotate to drive the inscribed gear pump unit 62, and the lubricating oil is output and supplied to the hybrid vehicle drive device 1 (see FIG. 1). Since the drive gear 71 is arranged with a gap G between the drive gear 71 and the case body 61, the boss portions 71a and 64a do not come into contact with each other when the oil pump device 60 is driven, and wear due to the contact does not occur. It can be suppressed.

[Oil pump device assembly procedure]
Next, the procedure for assembling the oil pump device 60 will be described. The drive shaft 70 and the drive gear 71 are integrally formed in advance. The drive shaft 70 integrally formed with the drive gear 71 is penetrated from the outside through the through hole of the boss portion 64a of the pump cover 64 from the tip of the small diameter portion 73. The inner rotor 67 is press-fitted into the small diameter portion 73 of the drive shaft 70 that penetrates the boss portion 64a. At this time, a tool or the like that applies a press-fitting pressing force is brought into contact with the end surface 70a of the drive shaft 70, and the drive shaft 70 is press-fitted until the step portion 74 comes into contact with the inner rotor 67. Here, the positional relationship between the step portion 74 and the drive gear 71 in the axial direction is such that the step portion 74 comes into contact with the inner rotor 67, so that the drive gear 71 has a gap G between the step portion 74 and the case body 61 in the axial direction. It is in a relationship of being arranged.

After press-fitting, the outer rotor 68 is assembled to the pump cover 64 to which the drive shaft 70, the drive gear 71, and the inner rotor 67 are rotatably assembled, and the pump body 63 is fastened with the bolt 65. The case body 61 assembled in this way is fastened to the casing 2 with bolts 66 and attached to the hybrid vehicle drive device 1 (see FIG. 1).

As described above, according to the oil pump device 60 of the present embodiment, the drive shaft 70 and the inner rotor 67 are brought into contact with the stepped portion 74 by press-fitting the drive shaft 70 into the inner rotor 67 at the time of assembly. Positioning with can be realized. Therefore, as in Patent Document 1, the work process can be reduced as compared with the case where the pin member is inserted into the tip of the drive shaft and the pin member is engaged with the groove of the inner rotor, so that the workability is improved. Can be improved.

Further, according to the oil pump device 60 of the present embodiment, the step portion 74 can position the drive shaft 70 and the inner rotor 67, and at the same time, secure a gap G between the drive gear 71 and the pump cover 64. can. As a result, it is possible to easily secure the gap G at the time of assembling the oil pump device 60, so that the workability can be further improved.

Further, according to the oil pump device 60 of the present embodiment, since the drive gear 71 is made of resin, a lightweight and inexpensive drive gear 71 can be obtained. Further, for example, even if the drive gear 71 is made of resin containing glass fiber and the pump cover 64 is made of aluminum, there is a gap G between the boss portion 71a of the drive gear 71 and the boss portion 64a of the pump cover 64. Is provided, so that the drive gear 71 and the pump cover 64 do not come into direct contact with each other. As a result, the wear of the pump cover 64 can be reduced even if the drive gear 71 is made of resin containing glass fibers in order to secure the strength.

In the above-described embodiment, the drive gear 71 is made of resin containing glass fiber, and the pump cover 64 is made of aluminum, but the present invention is not limited to this. For example, the drive gear 71 may be made of metal, and the pump cover 64 may be made of resin. In either case, since the gap G is provided between the boss portion 71a of the drive gear 71 and the boss portion 64a of the pump cover 64, wear due to contact during rotation can be suppressed.

Further, in the present embodiment, the case where the drive shaft 70 and the drive gear 71 are integrally formed by insert molding has been described, but the present invention is not limited to this. The drive shaft 70 and the drive gear 71 may be integrated, for example, by press-fitting or the like. Further, in the present embodiment, the case where the rotation transmission member is the drive gear 71 has been described, but the present invention is not limited to this, and the rotation transmission member may be applied to a sprocket, a chain, or the like.

Further, in the present embodiment, the case where the drive shaft 70 is fixed to the inner rotor 67 by tightening and fitting by press fitting has been described, but the present invention is not limited to this, and the drive shaft 70 may be tightened and fitted by another method. good. If it is not necessary to apply a load to the end face 70a of the drive shaft 70 when it is not press-fitted, it may not be exposed from the drive gear 71.

Further, in the present embodiment, the case where the drive shaft 70 is provided with the step portion 74 has been described, but the present invention is not limited to this. For example, when the drive shaft 70 is press-fitted into the inner rotor 67, a spacer is interposed between the drive gear 71 and the pump cover 64 even if the step portion 74 is not provided, and the spacer is removed after the press-fitting. As a result, positioning of the drive shaft 70 and the inner rotor 67 can be realized.

Further, in the present embodiment, the case where the drive gear 71 is provided adjacent to the pump cover 64 has been described, but the present invention is not limited to this, and for example, the drive gear 71 is arranged so as to be adjacent to the pump body 63. You may.

Further, in the present embodiment, the case where the oil pump device 60 has the internal gear pump unit 62 as the oil pressure generating unit has been described, but the present invention is not limited to this, and other types of oil pumps such as an external gear pump, for example, are described. May have.

<Summary of embodiments>
The above-described embodiment includes at least the following configurations. The oil pump device (60) of the present embodiment is formed by fastening the first member (63) and the second member (64) to the case body (61) having an accommodating space (S) inside. The pump gear (67) that generates oil by rotation is provided, and the oil pressure generating unit (62) provided in the accommodating space (S) and the case body (61) from the outside to the accommodating space (S). A drive shaft (70) that is provided through the case body (61) and rotates the pump gear (67) by being rotated, and a drive shaft (70) that is integrally provided outside the case body (61). The pump gear (67) is provided with a rotation transmission member (71) that transmits the input rotation to the drive shaft (70), and the pump gear (67) is provided with the drive shaft (70) with respect to the case body (61). The pump gear (67) and the drive shaft (70) are integrally provided by tightening and fitting, and the rotation transmission member (71) is provided. It is arranged with a gap (G) between it and the case body (61) in the axial direction.

According to this configuration, the drive shaft (70) and the pump gear (67) can be positioned by tightening and fitting the drive shaft (70) to the pump gear (67) at the time of assembly. Therefore, as in Patent Document 1, the work process can be reduced as compared with the case where the pin member is inserted into the tip of the drive shaft and the pin member is engaged with the groove of the inner rotor, so that the workability is improved. Can be improved.

Further, in the oil pump device (60) of the embodiment, the drive shaft (70) is made of metal, and the rotation transmission member (71) is made of resin. According to this configuration, since the rotation transmission member (71) can be made of resin, a lightweight and inexpensive rotation transmission member (71) can be obtained.

Further, in the oil pump device (60) of the embodiment, the pump gear (67) and the drive shaft (70) are press-fitted from the rotation transmission member (71) side in the axial direction of the drive shaft (70). The drive shaft (70) is integrally provided so that the end face (70a) on the rotation transmission member (71) side in the axial direction is exposed from the rotation transmission member (71). According to this configuration, by press-fitting the drive shaft (70), the pump gear (67) can be easily tightened and fitted. Moreover, since the end face (70a) of the drive shaft (70) is exposed, a tool or the like that applies a pressing force at the time of press-fitting can be brought into contact with the end face (70a) to apply a load to the end face (70a). can.

Further, in the oil pump device (60) of the embodiment, the drive shaft (70) is the rotation transmission member (71) in the axial direction of the fitting portion (75) tightly fitted to the pump gear (67). A step portion (74) having a diameter larger than that of the fitting portion (75) is provided on the side, and the step portion (74) has a rotation transmission member (71) between the case body (61) and the step portion (74). The drive shaft (70) tightly fitted to the fitting portion (75) is positioned in the axial direction so as to be arranged with the gap (G). According to this configuration, when the oil pump device (60) is assembled, the drive shaft (70) is press-fitted into the pump gear (67) so that the step portion (74) comes into contact with the drive shaft (70) and the pump gear (70). Positioning with 67) can be realized. Therefore, workability can be further improved.

Further, in the oil pump device (60) of the embodiment, the first member (63) is a pump body (63) having the accommodation space (S), and the second member (64) is the pump. A pump cover (64) that closes the accommodation space (S) of the body (63), and the drive shaft (70) is provided so as to penetrate the pump cover (64), and the pump is provided in the axial direction. The body (63), the pump cover (64), and the rotation transmission member (71) are arranged in this order. According to this configuration, in the assembly process of the oil pump device (60), a pump cover (64) in which a drive shaft (70), a rotation transmission member (71), and a pump gear (67) are rotatably assembled, and a pump. The body (63) and the body (63) will be fastened. Therefore, since the pump body (63) has an accommodation space (S) and is usually larger than the pump cover (64), the drive shaft (70), the rotation transmission member (71), and the pump gear (67). ) Is rotatably assembled to the large pump body (63), and the workability can be improved as compared with the case where the assembly is fastened to the pump cover (64).

Further, in the oil pump device (60) of the embodiment, the rotation transmission member (71) is a gear that meshes with the rotation member (41) that transmits the drive rotation for traveling the vehicle. According to this configuration, it is not necessary to use a dedicated drive source for driving the oil pump device (60), so that it is possible to suppress an increase in the size of the vehicle and an increase in the number of parts.

Further, in the oil pump device (60) of the embodiment, the oil pressure generating unit (62) meshes with the inner rotor (67), which is the pump gear (67) having a plurality of external teeth, and the plurality of external teeth. An inscribed gear pump portion (62) having a plurality of internal teeth and an outer rotor (68) provided eccentrically with respect to the inner rotor (67). According to this configuration, an oil pump device (60) using an inscribed gear pump can be realized.

41 ... Differential ring gear (rotating member)
60 ... Oil pump device 61 ... Case body 62 ... Inscribed gear pump part (hydraulic generation part)
63 ... Pump body (first member)
64 ... Pump cover (second member)
67 ... Inner rotor (pump gear)
68 ... Outer rotor 70 ... Drive shaft 70a ... End face 71 ... Drive gear (rotation transmission member)
74 ... Step portion 75 ... Fitting part G ... Gap S ... Accommodating space

Claims (7)

A case body formed by fastening the first member and the second member and having a storage space inside,
It has a pump gear that generates flood control by rotation, and has a flood control generator provided in the accommodation space.
A drive shaft provided through the case body from the outside of the case body to the accommodation space and rotating the pump gear by being rotated,
A rotation transmission member that is integrally provided on the drive shaft outside the case body and transmits the input rotation to the drive shaft is provided.
The pump gear is provided so as to be positioned with respect to the case body in the axial direction of the drive shaft and rotatably supported.
The pump gear and the drive shaft are integrally provided by tightening and fitting.
The rotation transmission member is an oil pump device arranged with a gap between the rotation transmission member and the case body in the axial direction. The drive shaft is made of metal and
The oil pump device according to claim 1, wherein the rotation transmission member is made of resin. The pump gear and the drive shaft are integrally provided by press-fitting the drive shaft from the rotation transmission member side in the axial direction.
The oil pump device according to claim 2, wherein the drive shaft has an end face on the rotation transmission member side in the axial direction exposed from the rotation transmission member. The drive shaft has a stepped portion having a diameter larger than that of the fitting portion on the rotation transmission member side in the axial direction of the fitting portion that is tightly fitted to the pump gear.
The step portion is claimed to position the drive shaft tightly fitted to the fitting portion in the axial direction so that the rotation transmission member is arranged with the gap between the rotation transmission member and the case body. The oil pump device according to 2 or 3. The first member is a pump body having the accommodation space.
The second member is a pump cover that closes the accommodation space of the pump body.
The drive shaft is provided so as to penetrate the pump cover.
The oil pump device according to any one of claims 1 to 4, wherein the pump body, the pump cover, and the rotation transmission member are arranged in this order in the axial direction. The oil pump device according to any one of claims 1 to 5, wherein the rotation transmission member is a gear that meshes with a rotation member that transmits drive rotation for traveling a vehicle. The hydraulic pressure generating unit includes an inner rotor which is a pump gear having a plurality of external teeth, an outer rotor which has a plurality of internal teeth meshing with the plurality of external teeth and is provided eccentrically with respect to the inner rotor. The oil pump device according to any one of claims 1 to 6, which is an inscribed gear pump unit having the above.

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