JP2021025573A - Liquid pressure motor with speed reducer - Google Patents

Abstract

To achieve downsizing of a liquid pressure motor with a speed reducer.SOLUTION: A liquid pressure motor 100 with a speed reducer includes: a motor housing 11 which houses a motor part 20; a gear housing 32 having a housing recessed part 33 which opens on an end surface 32a and houses a speed reducing part 35, the gear housing 32 connected to the motor housing 11 in a state that the end surface 32a is butted with an end surface 12a of the motor housing 11; and an O ring 50 which seals a gap between the end surface 12a of the motor housing 11 and the end surface 32a of the gear housing 32. The speed reducing part 35 has a first planetary gear mechanism 40 which reduces a speed of rotation of a motor shaft 21 and outputs the rotation. A first ring gear 42 of the first planetary gear mechanism 40 has a protruding part 42a protruding from the end surface 32a of the gear housing 32 to the motor housing 11. The O ring 50 is supported at its inner periphery by the protruding part 42a of the first ring gear 42.SELECTED DRAWING: Figure 2

Description

The present invention relates to a hydraulic motor with a speed reducer.

Patent Document 1 discloses a hydraulic motor to which a speed reducer is attached. This hydraulic motor includes a housing composed of a case and a plate, and an O-ring is provided on a mating surface between the case and the speed reducer.

JP-A-2014-13709

In the hydraulic motor described in Patent Document 1, an annular seal groove for accommodating the O-ring is formed on the mating surface of the speed reducer. As described above, in the hydraulic motor with a speed reducer, a seal groove may be formed on any of the mating surfaces of the motor housing and the gear housing, and a seal member may be provided in the seal groove.

However, in such a case, the motor housing or the gear housing becomes larger in the radial direction of the motor shaft by the amount of forming the seal groove in the motor housing or the gear housing, and the hydraulic motor with a speed reducer becomes larger. To do.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce the size of a hydraulic motor with a speed reducer.

The present invention is a hydraulic motor with a speed reducer, and includes a motor unit in which the motor shaft is rotationally driven by supply and discharge of hydraulic fluid, a deceleration unit that decelerates the rotation of the motor shaft and outputs it through an output shaft, and a motor unit. A gear housing that has a motor housing for accommodating, an accommodating recess that opens at the end face and accommodates a reduction gear, and is connected to the motor housing with the end face abutting against the end face of the motor housing, and an end face and the gear housing of the motor housing. The reduction gear includes a first planetary gear mechanism that decelerates and outputs the rotation of the motor shaft, and the first planetary gear mechanism is connected to the motor shaft. The first sun gear to be formed, the first ring gear provided on the outside of the first sun gear and attached to the inner peripheral surface of the accommodating recess, and the first sun gear and the first ring gear provided between the first sun gear and the first ring gear. It has a plurality of first planetary gears that mesh with each other and a first carrier that connects the plurality of first planetary gears to each other, and the first ring gear has a protruding portion that protrudes from the end face of the gear housing toward the motor housing. The seal member is characterized in that the inner circumference is supported by the protruding portion of the first ring gear.

In the present invention, since the inner circumference of the seal member is supported by the first ring gear of the first planetary gear mechanism, the seal groove formed in the motor housing or the gear housing can be eliminated.

Further, the present invention is characterized in that the protruding portion of the first ring gear is fitted into a fitting hole formed in the motor housing.

In the present invention, the inro structure is formed by the protrusion of the first ring gear and the fitting hole of the motor housing, and the motor housing and the gear housing can be aligned. Therefore, since it is not necessary to form the convex portion forming the in-row structure in the gear housing, the processing man-hours can be reduced, the cost can be reduced, and the increase in size of the gear housing can be suppressed.

Further, the present invention is characterized in that the motor housing is provided with a retaining portion that faces the first ring gear in the axial direction of the first ring gear and forms a disconnection of the first ring gear from the inner peripheral surface of the gear housing. And.

In the present invention, since the retaining portion of the motor housing prevents the first ring gear from coming off from the gear housing, no other member such as a pin for preventing the pulling out is required. Therefore, the cost of the hydraulic motor with a speed reducer can be reduced.

Further, in the present invention, the first ring gear has a protrusion formed so as to extend in the axial direction in a part in the circumferential direction and protrudes radially outward from the outer peripheral surface of the first ring gear, and the protrusion is a gear housing. It is press-fitted into the inner peripheral surface of the accommodating recess, and the outer peripheral surface of the protruding portion is a cylindrical surface on which the protruding portion is not provided, and the sealing member is characterized in that the inner circumference is supported by the cylindrical surface of the protruding portion.

In the present invention, a protrusion provided on a part of the first ring gear in the circumferential direction is press-fitted into the inner peripheral surface of the accommodating recess of the gear housing, so that a groove is formed on the inner peripheral surface of the accommodating recess by press-fitting the protrusion. It is formed. The groove formed in this way is locked to the first ring gear in the circumferential direction. Therefore, the relative rotation of the first ring gear with respect to the gear housing is regulated by the protrusion of the first ring gear and the groove formed on the inner peripheral surface of the accommodating recess of the gear housing.

Further, in the present invention, the reduction gear further includes a second planetary gear mechanism that decelerates the output of the first planetary gear mechanism and transmits the output to the output shaft, and the second planetary gear mechanism is a carrier of the first planetary gear mechanism. A second sun gear that rotates with the rotation of the second sun gear, a second ring gear that is provided on the outside of the second sun gear and attached to the inner peripheral surface of the accommodating recess, and a second sun gear that is provided between the second sun gear and the second ring gear. It has a plurality of second planetary gears that mesh with each of the second ring gears, and a second carrier that connects the plurality of second planetary gears to each other and the output shaft is connected to each other, and the reduction portion is the outer peripheral surface of the first ring gear. It further has a pin member provided over the outer peripheral surface of the second ring gear, and a pin groove into which the pin member is inserted is formed on the inner peripheral surface of the accommodating recess, and the pin member provides the first ring gear and the first ring gear to the gear housing. 2 The relative rotation of the ring gear is regulated.

In the present invention, both the first ring gear and the second ring gear are prevented from rotating by the pin member. Further, since the deceleration unit has a two-stage deceleration mechanism, the degree of freedom in designing the reduction ratio is improved.

According to the present invention, the hydraulic motor with a speed reducer can be miniaturized.

It is sectional drawing of the hydraulic motor with a reduction gear which concerns on 1st Embodiment of this invention. It is an enlarged sectional view which shows the mounting structure of the motor housing and the gear housing of the hydraulic motor with a speed reducer which concerns on 1st Embodiment of this invention. FIG. 5 is a schematic view of a gear housing according to a first embodiment of the present invention and a first ring gear inserted into the gear housing as viewed from the axial direction of the first ring gear. It is a top view of the 1st ring gear which concerns on 1st Embodiment of this invention. It is an enlarged sectional view which shows the mounting structure of the motor housing and the gear housing of the hydraulic motor with a speed reducer which concerns on 2nd Embodiment of this invention.

(First Embodiment)
Hereinafter, the hydraulic motor 100 with a speed reducer according to the first embodiment of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, the hydraulic motor 100 with a speed reducer decelerates and outputs a hydraulic motor (hydraulic motor) 10 that is rotationally driven by supplying and discharging hydraulic oil as a hydraulic fluid, and the hydraulic motor 10. The speed reducer 30 is provided.

The hydraulic motor 10 includes a motor unit 20 in which the motor shaft 21 rotates by supplying and discharging hydraulic oil, and a motor housing 11 accommodating the motor unit 20.

The motor unit 20 includes a motor shaft 21 and a cylinder block 22 that is connected to the motor shaft 21 and rotates integrally with the motor shaft 21. The motor shaft 21 is rotatably supported by the motor housing 11 via bearings 15 and 16. The motor housing 11 is divided into a housing body 12 in which a motor accommodating recess 11a that opens on one end surface is formed, and a lid member 13 that is coupled to the housing body 12 via a bolt (not shown) and covers the opening of the housing body 12. Will be done. One end of the motor shaft 21 is inserted into the gear housing 32, which will be described later, through the housing body 12.

The cylinder block 22 is provided with a plurality of cylinders 23 arranged on concentric circles centered on the axis of the motor shaft 21 in parallel with the motor shaft 21. The cylinder 23 opens at one end surface of the cylinder block 22, and a piston 24 defining a volume chamber 25 is inserted into each cylinder 23 so as to be reciprocally slidable.

A shoe 26 is connected to the tip of the piston 24 via a spherical seat 24a. An inclined surface 13a that is inclined with respect to the motor shaft 21 is formed on the lid member 13, and the swash plate 27 is fixed to the inclined surface 13a. The shoe 26 comes into surface contact with the swash plate 27 fixed to the lid member 13. Each piston 24 reciprocates in the cylinder 23 with a stroke amount corresponding to the tilt angle of the swash plate 27 with which each shoe 26 is in sliding contact.

A valve plate 28 with which the base end surface of the cylinder block 22 is in sliding contact is attached between the bottom of the housing body 12 and the cylinder block 22. The valve plate 28 has a supply port (not shown) that communicates with the hydraulic source and a discharge port (not shown) that communicates with the tank side. Each piston 24 protrudes from the cylinder 23 by the oil pressure guided from the hydraulic source to each volume chamber 25 via the supply port, and each piston 24 pushes the swash plate 27 through the shoe 26 to rotate the cylinder block 22. The rotation of the cylinder block 22 drives the motor shaft 21 to rotate.

Here, as the hydraulic motor, a swash plate may be fixed to the bottom of the housing body and provided between the cylinder block and the bottom of the housing body. In other words, a hydraulic motor in which a swash plate is provided at the position of the valve plate 28 in FIG. 1 is known. In such a case, in order to replace the swash plate and change the stroke amount of the piston, it is necessary to remove the lid member of the motor housing and the cylinder block and replace the swash plate fixed to the bottom of the housing body.

On the other hand, in the present embodiment, since the swash plate 27 is fixed to the lid member 13 instead of the housing main body 12, the piston can be replaced without removing the cylinder block 22 by exchanging the swash plate 27 together with the lid member 13. The stroke amount of 24 can be easily changed.

The speed reducer 30 has an output shaft 31, a speed reduction unit 35 that decelerates the rotation of the motor shaft 21 of the motor unit 20 and outputs the speed through the output shaft 31, and a gear housing 32 that houses the speed reduction unit 35.

The gear housing 32 has an accommodating recess 33 that opens in the end surface 32a and accommodates the reduction gear 35. The gear housing 32 is connected to the housing body 12 in a state where the end surface 32a is abutted against the end surface 12a of the housing body 12 of the motor housing 11. The gear housing 32 is provided with a mounting flange 34 for mounting on another device or the like. An O-ring 50 is provided between the housing body 12 of the motor housing 11 and the gear housing 32 as a sealing member for sealing the gap between the end surface 12a of the housing body 12 and the end surface 32a of the gear housing 32. The connection structure between the motor housing 11 and the gear housing 32 will be described in detail later.

The output shaft 31 is rotatably supported by the gear housing 32 via bearings 36 and 37. The output shaft 31 is inserted through the bottom portion of the gear housing 32, and one end thereof projects outward.

The speed reduction unit 35 has a first planetary gear mechanism 40 that decelerates the rotation of the motor shaft 21 of the motor unit 20 and outputs it, and a second planetary gear that decelerates the output of the first planetary gear mechanism 40 and transmits the output to the output shaft 31. It has a mechanism 45 and.

The first planetary gear mechanism 40 is attached to the inner peripheral surface of the first sun gear 41 to which the motor shaft 21 of the motor unit 20 is connected and the accommodating recess 33 of the gear housing 32 provided on the outside of the first sun gear 41. A plurality of first planetary gears 43 provided between the ring gear 42 and the first sun gear 41 and the first ring gear 42 and meshing with each of the first sun gear 41 and the first ring gear 42, and a plurality of first planetary gears 43 are connected to each other. It has a first carrier 44 and.

The first sun gear 41 is serrated and coupled with the end of the motor shaft 21 inserted into the accommodating recess 33 of the gear housing 32. As a result, the rotation of the motor shaft 21 of the motor unit 20 is transmitted to the first sun gear 41.

The first ring gear 42 is inserted into the inner circumference of the accommodating recess 33 of the gear housing 32. That is, the first ring gear 42 is not directly formed on the gear housing 32, but has a structure separate from the gear housing 32. Therefore, as compared with the case where the first ring gear 42 is directly formed (integrally formed) on the gear housing 2, heat treatment or the like can be easily performed, and the strength of the first ring gear 42 can be easily secured. One end of the first ring gear 42 in the axial direction is configured as a protruding portion 42a protruding from the end surface 32a of the gear housing 32 toward the motor housing 11. The detailed configuration of the first ring gear 42 will be described later.

The plurality of first planetary gears 43 are provided on the outside of the first sun gear 41 at equal angular intervals, and mesh with each of the first sun gear 41 and the first ring gear 42. When the first sun gear 41 rotates with the rotation of the motor shaft 21 of the motor unit 20, the first planetary gear 43 rotates around the first sun gear 41. Note that, in FIG. 1, only a single first planetary gear 43 is shown, and the other first planetary gear 43 is not shown.

The first carrier 44 rotatably holds a plurality of first planetary gears 43. As the plurality of first planetary gears 43 rotate around the first sun gear 41, the first carrier 44 rotates about the central axis of the motor shaft 21. A gear portion 44a is formed on the inner circumference of the first carrier 44.

The second planetary gear mechanism 45 is attached to the inner peripheral surface of the second sun gear 46, which is coaxially arranged with the motor shaft 21 of the motor unit 20, and the accommodating recess 33 of the gear housing 32, which is provided outside the second sun gear 46. A plurality of second planetary gears 48 provided between the second ring gear 47 and the second sun gear 46 and the second ring gear 47 and meshing with each of the second sun gear 46 and the second ring gear 47, and a plurality of second planetary gears 48 are provided. It has a second carrier 49, which is connected to each other.

The second sun gear 46 inserts the first carrier 44 of the first planetary gear mechanism 40 and meshes with the gear portion 44a formed on the inner circumference of the first carrier 44. As a result, the second sun gear 46 rotates with the rotation of the first carrier 44 of the first planetary gear mechanism 40.

Like the first ring gear 42, the second ring gear 47 is inserted into the inner circumference of the accommodating recess 33 of the gear housing 32. That is, the second ring gear 47 is not directly formed on the gear housing 32, but has a structure separate from the gear housing 32. The detailed configuration of the second ring gear 47 will also be described later.

The plurality of second planetary gears 48 are provided on the outer side of the second sun gear 46 at equal angular intervals, and mesh with each of the second sun gear 46 and the second ring gear 47. When the second sun gear 46 rotates, the second planetary gear 48 rotates around the second sun gear 46.

The second carrier 49 rotatably holds a plurality of second planetary gears 48. As the plurality of second planetary gears 48 rotate around the second sun gear 46, the second carrier 49 rotates about the central axis of the motor shaft 21.

The output shaft 31 is serrated-coupled to the inner peripheral surface of the second carrier 49. As a result, the rotation of the second carrier 49 is transmitted to the output shaft 31.

When the motor shaft 21 rotates due to the supply and discharge of hydraulic oil to the motor unit 20, the first sun gear 41 of the first planetary gear mechanism 40 connected to the motor shaft 21 rotates. As the first planetary gear 43 rotates around the first sun gear 41 with the rotation of the first sun gear 41, the first carrier 44 rotates, and the second planetary gear mechanism 45 meshes with the first carrier 44. The sun gear 46 rotates. When the second sun gear 46 rotates, the second planetary gear 48 that meshes with the second sun gear 46 rotates around the second sun gear 46, and the second carrier 49 rotates accordingly. As the second carrier 49 rotates, the output shaft 31 coupled to the second carrier 49 rotates. In this way, the rotation of the motor shaft 21 of the motor unit 20 is decelerated by the first planetary gear mechanism 40 and the second planetary gear mechanism 45 and transmitted to the output shaft 31.

Next, the mounting structure of the first ring gear 42 and the second ring gear 47 and the mounting structure of the motor housing 11 and the gear housing 32 will be described.

As shown in FIGS. 1 and 2, the accommodating recess 33 of the gear housing 32 has an insertion hole 33a into which the first ring gear 42 and the second ring gear 47 are inserted. The insertion hole 33a opens in the end surface 32a of the gear housing 32. Further, at the bottom of the insertion hole 33a, a positioning portion 33b which is an annular plane perpendicular to the motor shaft 21 of the motor portion 20 is provided.

The second ring gear 47 and the first ring gear 42 are inserted into the insertion hole 33a in this order from the positioning portion 33b toward the opening of the insertion hole 33a (the end surface 32a of the gear housing 32). The second ring gear 47 is inserted into the insertion hole 33a so as to abut the positioning portion 33b. The first ring gear 42 is inserted into the insertion hole 33a so as to abut on the end surface of the second ring gear 47. When the second ring gear 47 and the first ring gear 42 are inserted into the insertion holes 33a in this way, the protruding portion 42a, which is one end of the first ring gear 42 on the side opposite to the second ring gear 47 in the axial direction, becomes the gear housing 32. It protrudes from the end face 32a.

As shown in FIGS. 3 and 4, the first ring gear 42 is formed by extending the cylindrical surface 42b, which is a cylindrical outer peripheral surface, and a part of the cylindrical surface 42b in the circumferential direction in the axial direction of the first ring gear 42. It has a protrusion 42c that protrudes radially outward from the cylindrical surface 42b.

The broken line in FIG. 4 schematically shows the protrusion 42a. The protrusion 42c is formed so as not to reach the protrusion 42a protruding from the end surface 32a of the gear housing 32 in the first ring gear 42. That is, the outer peripheral surface of the protruding portion 42a is a cylindrical surface 42b on which the protruding portion 42c is not provided.

Further, the second ring gear 47 has the same shape as the first ring gear 42, and is formed so as to extend in the axial direction of the second ring gear 47 at a part of the cylindrical surface 47b and the circumferential direction of the cylindrical surface 47b from the cylindrical surface 47b. It has a protrusion 47c that protrudes outward in the radial direction. Since the second ring gear 47 has the same shape as the first ring gear 42, the specific illustration of each configuration is omitted, and in FIGS. 3 and 4, the second ring gear 47 corresponding to the configuration of the first ring gear 42 is omitted. The composition of is represented by the code in parentheses.

The cylindrical surface 42b of the first ring gear 42 is formed to have a diameter D1 slightly smaller than the inner diameter D2 of the insertion hole 33a of the accommodating recess 33 (see FIG. 3). Further, the maximum radial width W of the first ring gear 42 including the protrusion 42c (the maximum radial dimension passing through the apex of the protrusion 42c and the central axis of the first ring gear 42) is larger than the inner diameter D2 of the insertion hole 33a. It is formed large. Therefore, the first ring gear 42 is fitted into the insertion hole 33a on the cylindrical surface 42b excluding the portion facing the protrusion 42c across the central shaft, and faces the protrusion 42c and the protrusion 42c across the central shaft. A part of the cylindrical surface 42b is press-fitted into the insertion hole 33a. Similarly, the second ring gear 47 is fitted into the insertion hole 33a on the cylindrical surface 47b excluding the portion facing the protrusion 47c, and the protrusion 47c and a part of the cylindrical surface 47b facing the protrusion 47c are inserted holes. It is press-fitted into 33a.

When attaching the first ring gear 42 and the second ring gear 47 to the gear housing 32, first, the second ring gear 47 is inserted into the insertion hole 33a until it comes into contact with the positioning portion 33b of the insertion hole 33a. At this time, the protrusion 47c of the second ring gear 47 and a part of the cylindrical surface 47b facing the protrusion 47c are press-fitted into the insertion hole 33a.

When the protrusion 47c of the second ring gear 47 is press-fitted into the insertion hole 33a, the portion of the inner wall of the insertion hole 33a that contacts the protrusion 47c is dented outward in the radial direction due to the press-fitting force. Therefore, as the second ring gear 47 is inserted, a groove 33c having a shape corresponding to the protrusion 47c is formed on the inner wall of the insertion hole 33a so as to extend in the axial direction, as shown in FIG. Since the protrusion 47c is locked in the groove 33c thus generated in the circumferential direction, the second ring gear 47 is restricted from rotating relative to the gear housing 32. That is, the protrusion 47c provided on the outer periphery of the second ring gear 47 and the groove 33c of the insertion hole 33a formed by press-fitting the protrusion 47c form a detent for the second ring gear 47.

Next, the protrusion 42c of the first ring gear 42 is aligned with the groove 33c on the inner peripheral surface of the insertion hole 33a formed when the second ring gear 47 is inserted, and the first ring gear 47 is brought into contact with the second ring gear 47. The ring gear 42 is inserted into the insertion hole 33a. At this time, the protrusion 42c of the first ring gear 42 is press-fitted into the groove 33c of the gear housing 32. When the first ring gear 42 is inserted into the insertion hole 33a until it comes into contact with the second ring gear 47, the protruding portion 42a of the first ring gear 42 protrudes from the end surface 32a of the gear housing 32 (see FIGS. 1 and 2).

By inserting the first ring gear 42 into the insertion hole 33a so as to align the protrusion 42c of the first ring gear 42 with the groove 33c on the inner peripheral surface of the insertion hole 33a of the gear housing 32, the protrusion 42c of the first ring gear 42 And the groove 33c of the gear housing 32 are locked in the circumferential direction. As a result, the relative rotation of the first ring gear 42 with respect to the gear housing 32 is regulated. As described above, the first ring gear 42 and the second ring gear 47 are prevented from rotating by the protrusions 42c and 47c and the groove 33c formed on the inner peripheral surface of the insertion hole 33a, so that it is necessary to separately provide a rotation prevention member. There is no. As a result, the space for providing the detent member can be reduced, and the gear housing 32 and the motor housing 11 can be miniaturized.

As shown in FIGS. 1 and 2, a recess 12b is formed in the end surface 12a of the housing body 12 of the motor housing 11. The recess 12b has a tapered inner peripheral surface (conical surface) whose inner diameter increases toward the end surface 12a of the housing body 12. Further, as shown in FIG. 2, on the inner peripheral surface of the recess 12b, a fitting hole 12c into which the protruding portion 42a of the first ring gear 42 is fitted and the first ring gear 42 are prevented from coming off from the gear housing 32. The retaining portion 12d and the retaining portion 12d are formed. The retaining portion 12d is a bottom portion of the fitting hole 12c and is a flat surface formed in an annular shape.

The protruding portion 42a of the first ring gear 42 protruding from the end surface 32a of the gear housing 32 fits into the fitting hole 12c of the housing body 12 of the motor housing 11, so that the motor housing 11 and the gear housing 32 are positioned in the radial direction. Will be done. That is, the first ring gear 42 and the fitting hole 12c of the recess 12b form an in-row structure for positioning the motor housing 11 and the gear housing 32.

The motor housing 11 and the gear housing 32 are connected by bolts (not shown) in a state where the end surface 12a of the motor housing 11 and the end surface 32a of the gear housing 32 facing the end surface 12a and opening the accommodating recess 33 are butted against each other.

When the end surface 12a of the motor housing 11 and the end surface 32a of the gear housing 32 are butted against each other, the first ring gear 42 and the retaining portion 12d are separated from each other without contacting each other, as shown in FIG. Therefore, in the present embodiment, when the motor housing 11 and the gear housing 32 are assembled, the first ring gear 42 and the retaining portion 12d are provided before the end surface 12a of the motor housing 11 and the end surface 32a of the gear housing 32 come into contact with each other. Is prevented from coming into contact with. As a result, the motor housing 11 and the gear housing 32 can be assembled in a state where the end surface 12a of the motor housing 11 and the end surface 32a of the gear housing 32 are surely in contact with each other.

The inner circumference of the O-ring 50 is supported by the outer peripheral surface (cylindrical surface 42b) of the protruding portion 42a of the first ring gear 42. When the motor housing 11 and the gear housing 32 are connected, the O-ring 50 is axially compressed by the conical inner peripheral surface of the recess 12b in the motor housing 11 and the end surface 32a of the gear housing 32. That is, a space for accommodating the O-ring 50 is formed by the outer peripheral surface (cylindrical surface 42b) of the protruding portion 42a of the first ring gear 42, the end surface 32a of the gear housing 32, and the conical surface in the recess 12b of the motor housing 11. As a result, the gap between the end surface 12a of the motor housing 11 and the end surface 32a of the gear housing 32 is sealed by the O-ring 50, and the hydraulic oil is prevented from leaking to the outside through the gap.

According to the above embodiment, the following effects are exhibited.

In the hydraulic motor 100 with a speed reducer, the inner circumference of the O-ring 50 is supported by the first ring gear 42, and a section for accommodating the O-ring 50 is formed by the outer peripheral surface of the protruding portion 42a of the first ring gear 42. Therefore, the gear housing 32 and the motor housing 11 can be miniaturized in the radial direction of the motor shaft 21 as compared with the case where an annular seal groove is formed on the end surface 32a of the gear housing 32 or the end surface 12a of the motor housing 11. it can. That is, since the space for forming the seal groove on the end surface 32a of the gear housing 32 or the end surface 12a of the motor housing 11 can be reduced, the gear housing 32, the motor housing 11, and the hydraulic pressure motor 100 with a speed reducer can be reduced in size. Can be transformed into.

Further, the first ring gear 42 and the second ring gear 47 are restricted from rotating relative to the gear housing 32 by press-fitting the protrusions 42c and 47c formed on the outer peripheral surfaces into the insertion holes 33a of the gear housing 32. Since a detent member such as a pin is not used to stop the rotation of the first ring gear 42 and the second ring gear 47, the space for providing the detent member can be reduced, and the hydraulic motor 100 with a speed reducer is further miniaturized.

Further, the protruding portion 42c of the first ring gear 42 that supports the inner circumference of the O-ring 50 is not formed with the protruding portion 42c, and the outer peripheral surface of the protruding portion 42a is formed as a cylindrical surface 42b. In this way, since the contact between the protrusion 42c and the O-ring 50 is avoided, the protrusion 42c prevents the O-ring 50 from being deformed, and the end face 32a of the gear housing 32 and the end face 12a of the motor housing 11 prevent the O-ring 50 from being deformed. The O-ring 50 can be compressed by a desired compression amount. Therefore, the O-ring 50 can exhibit the desired sealing performance.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. Hereinafter, the points different from those of the first embodiment will be mainly described, and the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the first embodiment and the second embodiment, the configuration of the detent of the first ring gear 42 of the first planetary gear mechanism 40 and the second ring gear 47 of the second planetary gear mechanism 45 with respect to the gear housing 32 is different.

Specifically, the first ring gear 142 and the second ring gear 147 according to the second embodiment do not have the protrusions 42c and 47c as in the first embodiment, and the cylindrical surfaces 42b and 47b, respectively, are gears. It fits into the insertion hole 33a of the housing 32. On the other hand, on the outer peripheral surface of the first ring gear 142, a first groove 142a that opens at an end surface facing the second ring gear 147 and extends in the axial direction is formed. Further, on the outer peripheral surface of the second ring gear 147, a second groove 147a that opens at the end surface facing the first ring gear 142 and extends in the axial direction is formed. The first groove 142a and the second groove 147a are grooves having a substantially semicircular cross section, respectively.

A pin groove 133c extending in the axial direction is provided on the inner peripheral surface of the insertion hole 33a of the gear housing 32. The pin groove 133c is a groove having a semicircular cross section.

Further, the reduction gear 35 has a pin member 60 provided over the first groove 142a of the first ring gear 142, the second groove 147a of the second ring gear 147, and the pin groove 133c of the gear housing 32. The pin member 60 has a circular cross section, is locked in the circumferential direction with respect to the first groove 142a of the first ring gear 142 and the second groove 147a of the second ring gear 147, and is locked in the pin groove 133c of the gear housing 32. On the other hand, it is locked in the circumferential direction.

As a result, the first ring gear 142 and the second ring gear 147 are locked in the circumferential direction with respect to the gear housing 32 via the pin member 60, and the relative rotation of the first ring gear 142 and the second ring gear 147 with respect to the gear housing 32 is restricted. Will be done.

When assembling the first ring gear 142 and the second ring gear 147 to the gear housing 32, first, the second ring gear 147 is fitted into the insertion hole 33a and is inserted into the insertion hole 33a until it comes into contact with the positioning portion 33b of the gear housing 32. insert. At this time, the second ring gear 147 is inserted into the insertion hole 33a so that the position of the second groove 147a of the second ring gear 147 and the pin groove 133c of the gear housing 32 are aligned. As a result, the pin hole 61 having a substantially circular cross section is formed by the second groove 147a of the second ring gear 147 and the pin groove 133c of the gear housing 32.

Next, the pin member 60 is inserted into the pin hole 61 formed by the second groove 147a of the second ring gear 147 and the pin groove 133c of the gear housing 32. The pin groove 133c of the gear housing 32 extends toward the end surface 32a of the gear housing 32 so that the pin member 60 can be inserted into the pin hole 61, and is formed with a sufficient axial length.

Next, the pin member 60 is inserted into the first groove 142a of the first ring gear 142, and the first ring gear 142 is inserted into the insertion hole 33a. As a result, the first ring gear 142 and the second ring gear 147 are attached to the gear housing 32 by restricting the relative rotation with respect to the gear housing 32 by the pin member 60.

The second embodiment as described above also has the same effects as those in the first embodiment.

Further, in the hydraulic motor 100 with a speed reducer according to the second embodiment, the first ring gear 142 and the second ring gear 147 are not press-fitted into the insertion holes 33a, but are fitted to each other. Therefore, the first ring gear 142, the second ring gear 147, and the pin member 60 inserted over both of them can move in the axial direction in the insertion hole 33a, but the motor housing 11 is provided with a retaining portion 12d. Therefore, the first ring gear 142 is prevented from coming off from the insertion hole 33a.

Next, a modification of each of the above embodiments will be described.

In the first embodiment, the speed reduction unit 35 has a first planetary gear mechanism 40 and a second planetary gear mechanism 45, but this configuration is not essential. The speed reduction unit 35 may not have the second planetary gear mechanism 45 but may have only the first planetary gear mechanism 40. Further, in the first embodiment, when the reduction unit 35 has the first planetary gear mechanism 40 and the second planetary gear mechanism 45, the first ring gear 42 and the second ring gear 47 may be integrally formed. In other words, the ring gears of the first planetary gear mechanism 40 and the second planetary gear mechanism 45 may be a single ring gear in common. In this case, the common single ring gear corresponds to the "first ring gear" in the claims.

Further, in the first embodiment, the first ring gear 42 and the second ring gear 47 have a single protrusion 42c and 47c, respectively. On the other hand, the first ring gear 42 and the second ring gear 47 may have a plurality of protrusions 42c and 47c provided side by side in the circumferential direction, respectively. Further, if the first ring gear 42 and the second ring gear 47 can be prevented from rotating with respect to the gear housing 32, the protrusions 42c and 47c are not limited to those provided even in a part of the circumferential direction, but are provided on the entire circumferential direction. It may be provided, in other words, the annular protrusions 42c and 47c may be provided.

Further, in the second embodiment, a single pin member 60 is provided. On the other hand, a plurality of pin members 60 may be provided, and the first groove 142a of the first ring gear 142, the second groove 147a of the second ring gear 147, and the gear housing 32 correspond to the number of pin members 60. The pin groove 133c of the above may be formed.

Hereinafter, the configurations, actions, and effects of the embodiments of the present invention will be collectively described.

The hydraulic motor 100 with a speed reducer according to the first and second embodiments decelerates the rotation of the motor unit 20 in which the motor shaft 21 is rotationally driven by the supply and discharge of hydraulic oil, and outputs the motor shaft 21 through the output shaft 31. A deceleration unit 35, a motor housing 11 for accommodating the motor unit 20, and an accommodating recess 33 which opens in the end surface 32a and accommodates the deceleration unit 35, and the end surface 32a is abutted against the end surface 12a of the motor housing 11. A gear housing 32 connected to the motor housing 11 and an O-ring 50 for sealing between the end surface 12a of the motor housing 11 and the end surface 32a of the gear housing 32 are provided, and the reduction gear 35 is a rotation of the motor shaft 21. The first planetary gear mechanism 40 has a first planetary gear mechanism 40 for decelerating and outputting the gear, and the first planetary gear mechanism 40 has a first sun gear 41 to which a motor shaft 21 is connected and a housing recess 33 provided outside the first sun gear 41. A plurality of first planetary gears 43 provided between the first ring gears 42 and 142 mounted on the inner peripheral surface and the first sun gear 41 and the first ring gear 42 and meshing with each of the first sun gear 41 and the first ring gears 42 and 142. And a first carrier 44 that connects a plurality of first planetary gears 43 to each other, and the first ring gears 42 and 142 have a protruding portion 42a that protrudes from the end surface 32a of the gear housing 32 toward the motor housing 11. The inner circumference of the O-ring 50 is supported by the protruding portions 42a of the first ring gears 42 and 142.

In this configuration, since the inner circumference of the O-ring 50 is supported by the first ring gear 42 of the first planetary gear mechanism 40, the seal groove formed in the motor housing 11 or the gear housing 32 can be eliminated. Therefore, the hydraulic motor 100 with a speed reducer can be miniaturized.

Further, in the hydraulic motor 100 with a speed reducer according to the first and second embodiments, the protruding portions 42a of the first ring gears 42 and 142 are fitted into the fitting holes 12c formed in the motor housing 11.

In this configuration, the in-row structure is formed by the protruding portion 42a of the first ring gear 42 and the fitting hole 12c of the motor housing 11, and the motor housing 11 and the gear housing 32 can be aligned. Therefore, since it is not necessary to form the convex portion forming the in-row structure in the gear housing 32, the processing man-hours can be reduced, the cost can be reduced, and the increase in size of the gear housing 32 can be suppressed.

Further, in the hydraulic motor 100 with a speed reducer according to the first and second embodiments, the motor housing 11 faces the first ring gears 42 and 142 in the axial direction of the first ring gears 42 and 142, and the gear housing 32 A retaining portion 12d is provided to form the first ring gears 42 and 142 from coming off from the inner peripheral surface.

In this configuration, the retaining portion 12d of the motor housing 11 prevents the first ring gears 42 and 142 from coming off from the gear housing 32, so that no other member such as a pin for preventing the pulling out is required. Therefore, the cost of the hydraulic motor 100 with a speed reducer can be reduced.

Further, in the hydraulic motor 100 with a speed reducer according to the first embodiment, the first ring gear 42 is formed so as to extend in the axial direction in a part in the circumferential direction and protrudes radially outward from the outer peripheral surface of the first ring gear 42. It has a protrusion 42c, the protrusion 42c is press-fitted into the inner peripheral surface of the accommodating recess 33 of the gear housing 32, and the outer peripheral surface of the protrusion 42a is a cylindrical surface 42b in which the protrusion 42c is not provided, and is an O-ring. The inner circumference of 50 is supported by the cylindrical surface 42b of the protruding portion 42a.

In this configuration, the protrusion 42c provided on a part of the first ring gear 42 in the circumferential direction is press-fitted into the inner peripheral surface of the accommodation recess 33 of the gear housing 32, so that the protrusion is formed on the inner peripheral surface of the accommodation recess 33. The groove 33c is formed by press-fitting 42c. The groove 33c formed in this way is locked to the first ring gear 42 in the circumferential direction. Therefore, the relative rotation of the first ring gear 42 with respect to the gear housing 32 is regulated by the protrusion 42c of the first ring gear 42 and the groove 33c formed on the inner peripheral surface of the accommodating recess 33 of the gear housing 32.

Further, in the hydraulic motor 100 with a speed reducer according to the second embodiment, the speed reduction unit 35 further includes a second planetary gear mechanism 45 that decelerates the output of the first planetary gear mechanism 40 and transmits the output to the output shaft 31. The second planetary gear mechanism 45 is attached to the inner peripheral surface of the second sun gear 46, which rotates with the rotation of the first carrier 44 of the first planet gear mechanism 40, and the accommodating recess 33 provided outside the second sun gear 46. A plurality of second planetary gears 48 provided between the second ring gear 147 and the second sun gear 46 and the second ring gear 147 and meshing with each of the second sun gear 46 and the second ring gear 47, and a plurality of second planetary gears 48 are provided. A second carrier 49, which is connected to each other and to which an output shaft 31 is connected, is provided, and the reduction gear 35 further includes a pin member 60 provided over the outer peripheral surface of the first ring gear 142 and the outer peripheral surface of the second ring gear 147. A pin groove 133c into which the pin member 60 is inserted is formed on the inner peripheral surface of the accommodating recess 33, and the pin member 60 restricts the relative rotation of the first ring gear 142 and the second ring gear 147 with respect to the gear housing 32. Will be done.

In this configuration, the pin member 60 prevents both the first ring gear 142 and the second ring gear 147 from rotating. Further, since the deceleration unit 35 has a two-stage deceleration mechanism, the degree of freedom in designing the reduction ratio is improved.

Although the embodiments of the present invention have been described above, the above embodiments are only a part of the application examples of the present invention, and the technical scope of the present invention is limited to the specific configurations of the above embodiments. Absent.

11 ... motor housing, 12a ... end face, 12c ... fitting hole, 12d ... retaining part, 20 ... motor part, 21 ... motor shaft, 31 ... output shaft, 32 ... gear housing, 32a ... end face, 33 ... accommodating recess, 33c ... groove, 35 ... reduction unit, 40 ... first planetary gear mechanism, 41 ... first sun gear, 42, 142 ... first ring gear, 42a ... protrusion, 42b ... cylindrical surface, 42c ... protrusion, 43 ... first Planetary gear, 44 ... 1st carrier, 45 ... 2nd planetary gear mechanism, 46 ... 2nd sun gear, 47,147 ... 2nd ring gear, 47b ... Cylindrical surface, 47c ... Protrusion, 48 ... 2nd planetary gear, 49 ... 2nd Carrier, 50 ... O-ring (seal member), 60 ... pin member, 133c ... pin groove, 100 ... hydraulic motor with reducer

Claims (5)

A motor unit in which the motor shaft is rotationally driven by the supply and discharge of hydraulic fluid,
A deceleration unit that decelerates the rotation of the motor shaft and outputs it through the output shaft,
A motor housing that houses the motor unit and
A gear housing that has an accommodating recess that opens at the end surface and accommodates the deceleration portion, and is connected to the motor housing with the end surface abutting against the end surface of the motor housing.
A seal member for sealing between the end face of the motor housing and the end face of the gear housing is provided.
The deceleration unit has a first planetary gear mechanism that decelerates and outputs the rotation of the motor shaft.
The first planetary gear mechanism is
The first sun gear to which the motor shaft is connected and
A first ring gear provided on the outside of the first sun gear and attached to the inner peripheral surface of the accommodating recess.
A plurality of first planetary gears provided between the first sun gear and the first ring gear and meshing with each of the first sun gear and the first ring gear.
It has a first carrier that connects a plurality of the first planetary gears to each other, and has.
The first ring gear has a protruding portion that protrudes from the end face of the gear housing toward the motor housing.
The seal member is a hydraulic motor with a speed reducer, wherein the inner circumference is supported by the protruding portion of the first ring gear. The hydraulic motor with a speed reducer according to claim 1, wherein the protruding portion of the first ring gear is fitted into a fitting hole formed in the motor housing. The motor housing is characterized by being provided with a retaining portion that faces the first ring gear in the axial direction of the first ring gear and forms the first ring gear coming out of the accommodating recess of the gear housing. The hydraulic motor with a speed reducer according to claim 1 or 2. The first ring gear has a protrusion that is formed so as to extend in the axial direction in a part of the circumferential direction and projects radially outward from the outer peripheral surface of the first ring gear.
The protrusion is press-fitted into the inner peripheral surface of the accommodating recess of the gear housing.
The outer peripheral surface of the protruding portion is a cylindrical surface on which the protruding portion is not provided.
The hydraulic motor with a speed reducer according to any one of claims 1 to 3, wherein the seal member has an inner circumference supported by the cylindrical surface of the protruding portion. The reduction gear further includes a second planetary gear mechanism that decelerates the output of the first planetary gear mechanism and transmits the output to the output shaft.
The second planetary gear mechanism
A second sun gear that rotates with the rotation of the first carrier of the first planetary gear mechanism, and
A second ring gear provided on the outside of the second sun gear and attached to the inner peripheral surface of the accommodating recess,
A plurality of second planetary gears provided between the second sun gear and the second ring gear and meshing with each of the second sun gear and the second ring gear.
It has a second carrier in which a plurality of the second planetary gears are connected to each other and the output shaft is connected to each other.
The reduction gear further includes a pin member provided over the outer peripheral surface of the first ring gear and the outer peripheral surface of the second ring gear.
A pin groove into which the pin member is inserted is formed on the inner peripheral surface of the accommodating recess.
The hydraulic motor with a speed reducer according to any one of claims 1 to 3, wherein the pin member regulates the relative rotation of the first ring gear and the second ring gear with respect to the gear housing.

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