JPH11182402A - Liquid-operated motor with reduction gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid-operated motor with a reduction gear equipped with a rotary joint for smoothing the flow of fluid, and moreover having compact structure. SOLUTION: This motor is equipped with a swash plate type liquid-operated motor 21 for transmitting the rotation of a swash plate 36 to an output shaft 35, and a planetary gear reduction gear 22; and a rotating frame 80 is rotatably arranged in the outer periphery of a motor housing 30. Ringlike oil grooves 106, 107, and 108 are formed on the opposite peripheral surfaces 101 and 102 of the housing 30 and the frame 80, and fluid ports E1, E2, E3, F1, F2, and F3, being communicated to the housing 30 and the frame 80 through oil groove 106, 107 and 108, are drilledly provided to constitute a rotary joint 85 by the housing 30 and the frame 80. A brake mechanism 60 for a swash plate 36 is incorporated in the housing 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic motor with a reduction gear used for driving a swivel of a construction machine such as a hydraulic shovel.

[0002]

2. Description of the Related Art For example, in a construction machine such as a hydraulic excavator, a revolving frame is mounted on a traveling frame provided with a traveling motor via a hydraulic revolving drive device, and an engine is mounted on the revolving frame. , A hydraulic pump, and a hydraulic oil tank. The hydraulic pump is driven by the engine, and the revolving frame and the traveling motor are driven by the hydraulic pressure generated by the hydraulic pump. Therefore, a rotary joint is required to supply hydraulic pressure from the revolving frame to the traveling motor, and the rotary joint is installed in the revolving drive device.

FIG. 3 shows an example of a conventional hydraulic drive shovel having a rotary joint.

In FIG. 1, reference numeral 1 denotes a revolving frame, and 2 denotes a traveling frame (fixed frame). The revolving frame 1 is provided with a hydraulic motor 3 for revolving drive, and a pinion 4 is fixed to an output shaft thereof. An outer wheel 5 is fixed to the revolving frame 1, and an inner wheel 6 fixed to the traveling system frame 2 is arranged on the inner peripheral side so as to support the outer wheel 5. An internal gear that meshes with the pinion 4 is formed on the inner periphery of the inner ring 6, and the rotation of the pinion 4 causes the pinion 4 to orbit along the internal gear of the inner ring 6, whereby The revolving unit frame 1 turns with respect to the traveling system frame 2.

[0005] A support plate 7 is fixed to the traveling system frame 1, and a rotary joint 8 is attached to a box-shaped body 9 provided on the support plate 7.
Is attached. The rotary joint 8 distributes hydraulic pressure supplied from a hydraulic pump (not shown) mounted on the revolving frame 1 to a traveling motor or the like of the traveling system frame 2 (in some cases, other actuators).

By the way, in the above-mentioned turning drive device, the rotary joint 8 is formed separately from the driving hydraulic motor 3 and is installed at different places. Therefore, there is a problem that a large installation space is required and compactness is lacking.

Therefore, in order to realize a compact structure, a turning drive device described in Japanese Patent Publication No. 6-92663 has been provided.

FIG. 4 shows an example of the turning drive described in the publication.

In this turning drive device, a drive motor 12 is attached to one end of a casing 11, and the output of the drive motor 12 is transmitted through a planetary gear reducer 13 coaxially with the drive motor 12 inside the casing 11. A fluid port 16, 17 is provided between the casing 11 and the output shaft 14 through the annular groove 15. And the casing 11 and the output shaft 1
4 together form a rotary joint 18.

According to this turning drive, the casing 1
1, since the drive motor 12, the planetary gear reducer 13, and the rotary joint 18 are all assembled, advantages such as a relatively compact structure and a small installation space can be obtained.

[0011]

However, in the turning drive device shown in FIG. 4, the drive motor 12 is connected to one end of the casing 11 so as to protrude, and the output member of the planetary gear reducer 13 is driven. Output shaft 1 arranged on the axis of motor 12
4, the dimension in the axial direction was considerably long. In particular, since a plurality of annular grooves 15 need to be formed in the longitudinal direction of the output shaft 14 because the output shaft 14 and the casing 11 constitute the rotary joint 18, the axial dimension is further increased, and the size is reduced. There was still room for improvement in that respect.

Further, in this apparatus, since the fluid port 16 is formed inside the output shaft 14, the cross-sectional area of the fluid port 16 is limited, and there is a problem that the fluid passage resistance is increased.

The present invention has been made in view of such conventional problems, and is suitable for application as a swing drive device of a construction machine, and has a cross-sectional size of a fluid port constituting a rotary joint. It is an object of the present invention to provide a hydraulic motor with a speed reducer, which is hardly limited and can be made more compact.

[0014]

According to a first aspect of the present invention, there is provided a motor housing having a supply / discharge port for supplying / discharging a working fluid to / from an open end face thereof and rotating the swash plate contained in the motor housing. A swash plate type axial piston type hydraulic motor which is taken out to the outside by an output member, and a planetary gear reducer which has an input portion connected to an output member of the hydraulic motor and takes out a reduction output from an internal gear as an output portion. A rotating frame integrally having the internal gear is rotatably arranged on the outer periphery of a motor housing, and the motor housing and the rotating frame are formed with peripheral surfaces opposed to each other with a small gap when the two members rotate relative to each other; An annular groove continuous in the circumferential direction is formed on at least one of the opposing peripheral surfaces, one end of the motor housing communicates with the annular groove, and the other end of the motor housing A fluid port opening on an open end face is drilled, and a fluid port having one end communicating with the annular groove and the other end opening on the outer peripheral surface of the rotating frame is drilled in the rotary frame, and the motor housing and the rotary housing are rotated. The above problem has been solved by forming the rotary joint with the frame.

In the present invention, since the rotary joint is formed between the motor housing and the rotary frame of the speed reducer, the fluid port of the motor housing and the fluid port of the rotary frame are independent of the relative rotational positions of the two. , Are kept in communication through the annular groove. Therefore, regardless of the operation state of the hydraulic motor, the liquid can flow between the fluid port opened on the open end surface of the motor housing and the fluid port opened on the outer periphery of the rotating frame.

Further, it is possible to secure a sufficient sectional area of the oil passage without increasing the axial dimension.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view showing the structure of a hydraulic motor 20 with a reduction gear according to an embodiment of the present invention. The hydraulic motor 20 with a reduction gear is obtained by integrally combining a hydraulic motor 21 composed of a swash plate type axial piston motor and a planetary gear reducer 22 for reducing the output of the motor.

The hydraulic motor 21 includes a first housing 31,
Second housing 32, third housing (end cover)
The motor housing 30 is configured by arranging 33 in the axial direction and integrally connecting them with the through bolts 37.
In this case, the first housing 31 and the second housing 32
Is hidden inside, but the end surface of the third housing 33 as the end cover is exposed to the outside as an open end surface 33a. Further, a front cover 34 is further connected to a tip of the first housing 32.

The hydraulic motor 21 is of a type in which a swash plate 36 rotates and a cylinder barrel 32A is fixed to a motor housing 30.
2A is integrated with the second housing 32. In addition,
It is also possible to manufacture the cylinder barrel 32A with another configuration and then connect the cylinder barrel 32A to the second housing 32 with a spline or the like.

The swash plate 36 is a first swash plate in the motor housing 30.
It is arranged on the housing 31 side. The swash plate 36 is integrally formed with an output shaft 35 having a tip protruding outside the motor housing 30 from the first housing 31 and the front cover 34. In this case, the swash plate 36 and the output shaft 35 may not be integrally formed, but need to be connected so as to rotate integrally. The swash plate 36 is rotatable in the motor housing 30 by supporting the output shaft 35 with bearings 91 and 92 arranged in the first housing 31. The swash plate 36 and the output shaft 35 are connected to the motor housing 3.
It rotates around the rotation axis L set at the center of 0.

A plurality of cylinder holes 39 are formed at equal intervals on the circumference of the cylinder barrel 32A, and a piston 40 is inserted into each cylinder hole 39 so as to be able to protrude and retract toward the swash plate 36. . A slipper 41 is rotatably fitted to the spherical head of each piston 40, and each slipper 41 slidably contacts a thrust plate 42 arranged on the swash plate 36.

Third housing 33 and cylinder barrel 32
A valve plate 43 that rotates and comes into contact with the end surface of the cylinder barrel 32A is housed in the space secured between A and A. The valve plate 43 switches the communication oil passage between the main ports (supply / discharge ports for the working fluid) M1 and M2 opening to the open end face 33a of the third housing 33 and the cylinder hole 39 in the cylinder barrel 37. Board 36
Swash plate 36 and connecting shaft 47 so that they rotate in synchronization with the rotation of
Are connected by

The slippers 41 fitted to the heads of the respective pistons 40 are held by a retainer plate 45. A biasing force is applied to the retainer plate 45 by a spring-loaded guide ball 46, and the slipper 41 is pressed by the biasing force so as not to separate from the swash plate 36.

The swash plate 3 is provided in the motor housing 30.
A brake mechanism 60 for stopping the rotation of No. 6 is incorporated. The brake mechanism 60 in this case is of a multi-plate clutch type, and includes an outer periphery of the swash plate 36 and the first housing 3.
A plurality of friction plates 61 alternately stopped and engaged with the inner circumference of
A brake plunger 62 for pressing the friction plate 61 against the inner wall of the first housing 31 to generate a frictional force between the housing 31 and the friction plate 61 and between the friction plates 61; And a hydraulic oil chamber 64 that moves the brake plunger 62 in the opposite direction to the frictional engagement direction against the force of the brake spring 63 by introducing pressure oil. Motor housing 30 for introducing oil
And a pressure oil introduction passage 65 formed therein.
The brake plunger 62 is formed of an annular body having a step on the outer periphery, and a hydraulic oil chamber 64 is formed between the step wall surface and the wall surface of the first housing 31.

On the other hand, the planetary gear reducer 22 is disposed around an output shaft 35 protruding from the motor housing 30. The rotating frame 80 as an output member of the planetary gear reducer 22 extends to a position covering the outer periphery of the motor housing 30, and bearings 93 and 94 are provided on the outer periphery of the first housing 31 and the outer periphery of the second housing 32. And is rotatable around the rotation axis L.

The planetary gear reducer 22 has an internal gear U as a final output unit integrally formed on the inner periphery of the rotary frame 80.
And a spline 5 at the tip of the output shaft 35 of the hydraulic motor 21.
A first sun gear S1 connected via the first sun gear S1, a plurality of first planetary gears P1 arranged around the first sun gear S1 and meshing with the first sun gear S1 and the internal gear U; A first carrier C1 that rotatably holds P1 via a bearing 52 and a planetary pin K1, and a second sun gear S2 that is engaged with the first carrier C1 via a spline 53 and rotates around the output shaft 35. And the second sun gear S2
, A plurality of second planetary gears P2 meshing with the second sun gear S2 and the internal gear U, and a second planetary gear P2
And a second carrier C2 that is rotatably held via a bearing 54 and a planetary pin K2 and is engaged with the outer periphery of the front cover 34 via a spline 55.

In this planetary gear reducer 22, the output shaft 35
Rotates, the rotation is transmitted in the order of the first sun gear S1 → the first planetary gear P1 → the first carrier C1 → the second sun gear S2 → the second planetary gear P2 → the internal gear U, and the rotating frame 8
0 rotates. That is, the rotating frame 80 and the motor housing 30 rotate relative to each other.

In the hydraulic motor 20 with reduction gear, the motor housing 3 is positioned between the two bearings 93 and 94 disposed between the rotating frame 80 and the motor housing 30.
On the outer periphery of the rotation frame 80 and the inner periphery of the rotating frame 80, peripheral surfaces 101 and 102 facing each other with a minute gap 100 are formed. In addition, three circumferentially continuous annular oil grooves are arranged on the peripheral surface 102 on the motor housing 30 side (here, the outer peripheral surface of the second housing 32 integrated with the cylinder barrel 32A) in the direction of the rotation axis L. (Annular groove) 106, 10
7, 108 are formed. A fluid port E having one end communicating with the oil grooves 106, 107, and 108 at the motor housing 30 and the other end opening at the open end surface 33 a of the motor housing 30 (the outer end surface of the third housing 33).
1, E2 and E3 are drilled, while fluid ports F1, F2 and F3 are connected to the rotary frame 80 at one end to communicate with the oil grooves 106, 107 and 108, and at the other end to the outer peripheral surface of the rotary frame 80.
Are formed, whereby the motor housing 30 and the rotary frame 80 form a rotary joint 85.

A seal groove 109 is formed on both sides of each of the oil grooves 106, 107 and 108, and each of the seal grooves 109 is formed.
In addition, a seal ring (not shown) for making the oil grooves 106, 107, and 108 liquid-tight is disposed. Also, the rotating frame 80
Of the rotary frame 80 and the gap between the motor housing 30 are sealed by a seal ring 110 in a liquid-tight manner.

At the outer periphery of the motor housing 30 and the rotary frame 80, mounting flanges Y1 and Y2 for connecting to an external frame are formed, respectively. The mounting flange Y2 of the rotary frame 80 is located above the openings of the fluid ports F1, F2, F3.

Next, the operation will be described.

In the hydraulic motor 20 with a speed reducer, the brake spring 6
Since the force of No. 3 is acting on the friction plate 61, the brake is in effect and the swash plate 36 does not rotate.

To rotate from this state, first, pressurized oil is supplied from the hydraulic oil introduction passage 65 of the brake mechanism 60 to the hydraulic oil chamber 64.
To move the brake plunger 62 in the direction opposite to the frictional engagement direction against the force of the brake spring 63.
Then, the pressure contact with the friction plate 61 is released, and the brake is released.

In this state, when high-pressure oil flows into the main port M1 of the hydraulic motor 21, the high-pressure oil flows through the valve plate 43 to the cylinder hole 39 of the cylinder barrel 32A.
And acts on the end face of the piston 40 to
Is moved in the axial direction, and the slipper 41 is pressed against the swash plate 36. Then, due to the pressing action of the slipper 41 against the slope 36, a component force is generated in a direction orthogonal to the direction of movement of the piston 40, and this component force becomes a rotating force to rotate the swash plate 36, and the output shaft 35 Tell the rotation. During this operation, the high pressure side piston 40 moves from the top dead center (retraction limit) to the bottom dead center (projection limit), and the low pressure side piston 40 moves from the bottom dead center to the top dead center. After that, the low-pressure oil that has been activated is passed through the valve plate 43 to the main port M2.
More outflow.

When the output shaft 35 of the hydraulic motor 21 rotates, the rotation is changed by the first sun gear S1 in the planetary gear reducer 22, the first planetary gear P1, the first carrier C1, the second sun gear S2, and the second sun gear. The rotation is transmitted in the order of 2 planetary gears P2 → the internal gear U, and the rotating frame 80 rotates. During the rotation, the two fluid ports E1, F1, the fluid ports E2, F2, and the fluid ports E3, F3 are connected via the oil grooves 106, 107, 108 regardless of the relative rotational positions of the motor housing 30 and the rotating frame 80. Respectively, so that they are in communication with each other. Therefore, regardless of the operation state of the hydraulic motor 21, the fluid ports E 1, E 1 opening to the open end face 33 a of the motor housing 30 are provided.
2, E3 and a fluid port F opening on the outer periphery of the rotating frame 80.
The liquid can be circulated between the first, F2 and F3. That is, it can function as a rotary joint.

To stop the rotation, the brake mechanism 6
Release the 0 operating oil pressure. Then, a pressure contact force is applied to the friction plate 61 by the force of the brake spring 63, and the brake works to stop the rotation of the swash plate 36.

FIG. 2 shows a hydraulic excavator turning device.
An example in which the hydraulic motor with a speed reducer 20 according to the embodiment of the present invention is used will be described.

In the drawing, of the revolving frame 201 and the traveling frame 202 which need to be rotated relative to each other,
The revolving frame 201 is fixed to the flange Y1 of the motor housing 30, and the traveling frame 202 is
Is fixed to the flange Y2. Revolving body frame 20
1, an engine 203, a turning pump 205 and a traveling pump 206 driven by the engine 203,
A hydraulic oil tank 207 and the like are provided. A traveling motor 208 is installed on the traveling system frame 202.

Discharge port 205a of swivel pump 205
Is connected to the main port M1 of the hydraulic motor with reduction gear 20, and another main port M2 is connected to the hydraulic oil tank 207.
It is connected to the. Further, the discharge port 206a of the traveling pump 206 is connected to the fluid port E1 on the motor housing 30 side of the hydraulic motor 20 with a reduction gear, and the fluid port F1 on the rotating frame 80 side is connected to the inflow port 2 of the traveling motor 208.
08a. The outflow port 208b of the traveling motor 208 is connected to the fluid port F2 on the rotating frame 80 side, and the fluid port E2 on the motor housing 30 side is connected to the hydraulic oil tank 207. Similarly, the drain port 208c of the traveling motor 208 is connected to the fluid port F3 on the rotating frame 80 side, and the fluid port E3 on the motor housing 30 side is connected to the hydraulic oil tank 207.

By connecting the oil passages as described above, even when the traveling system frame 202 and the revolving body frame 201 make a relative revolving motion, the rotary joint 85 in the hydraulic motor 20 with a reduction gear can be connected without any trouble. Through the revolving frame 201
The hydraulic pressure can be supplied / discharged to / from the traveling motor 208 from above.

In the case of the hydraulic motor 20 with a speed reducer, the rotary frame 80 covering the outer periphery of the motor housing 30 is used as the final output member, so that the output shaft of the speed reducer can be omitted. , The axial length can be reduced. Further, a rotary joint 85 is constituted by the rotary frame 80 and the motor housing 30, and their opposing peripheral surfaces 101, 10
Since the oil grooves 106, 107, and 108 are arranged in 2,
The oil grooves 106, 107, 108 can be formed under conditions that are advantageous in terms of space, and it is not necessary to increase the axial dimension for forming the oil grooves 106, 107, 108. Therefore, the overall size can be reduced.

In the hydraulic motor with speed reducer 20, the fluid ports E1, E2, E3, F1, F2, and F3 are formed in the motor housing 30 and the rotary frame 80, which are advantageous in terms of space. Ports E1, E2, E3, F1,
F2 and F3 can be formed in a necessary and sufficient cross-sectional area,
The passage resistance of the fluid can be reduced.

In the hydraulic motor 20 with a reduction gear, the hydraulic motor 21 is attached to the open end face 33a of the motor housing 30.
Main ports M1, M2 and fluid ports E1, E2, E
Since all three openings are provided collectively, piping connection to the openings of the main ports M1, M2 and the fluid ports E1, E2, E3 can be easily performed. Similarly, since the openings of the fluid ports F1, F2, and F3 are arranged on the outer peripheral surface of the rotating frame 80, the pipe connection to the openings can be easily performed.

Further, according to the hydraulic motor with speed reducer 20, the cylinder barrel 32A is formed integrally with the second housing 32, and the second housing 32 and the rotary frame 80 form a rotary joint. In addition, the size of the second housing 32 and the cylinder barrel 32A can be reduced, and the path through which each fluid port passes can be easily set, and processing can be facilitated.

In the above embodiment, the oil grooves 106, 1
Although the case where 07 and 108 are provided on the peripheral surface 101 on the motor housing 30 side is shown, the oil grooves 106, 107 and 108 may be provided on the peripheral surface 102 on the rotating frame 80 side or on both sides. . The number of oil grooves may be changed as needed.

In the above-described embodiment, the brake mechanism is configured such that the braking force can be secured when the hydraulic motor or the braking hydraulic pressure is not operated. And the direction of movement of the brake plunger 62 by the braking oil pressure is reversed, or the brake fluid pressure can be applied to the opposite side of the brake plunger 62, so that the rotation of the swash plate 36 is more actively braked. It may have a function of performing

[0048]

As described above, according to the hydraulic motor with a speed reducer of the first aspect of the present invention, the output member of the planetary gear speed reducer is formed as a rotary frame disposed on the outer periphery of the motor housing of the hydraulic motor. Therefore, the output shaft of the speed reducer is not required, and the axial dimension can be reduced accordingly. In particular, the rotary frame and the motor housing form a rotary joint, and the annular groove, which is a component of the rotary joint, is arranged on the outer peripheral surface of the motor housing, which has not been conventionally used. Can be formed under favorable conditions,
In order to form the annular groove, the size of the output shaft is intentionally lengthened, so that the axial size does not increase as a result, and the overall size can be reduced.

Also, in this apparatus, the fluid port is not formed in the shaft having a small cross-sectional area, but is formed in the motor housing having a large cross section. Without being limited, the cross-sectional area of the fluid port can be increased, and the flow resistance of the fluid can be reduced.

Further, since all the working fluid supply / discharge ports and fluid port openings of the hydraulic motor are integrated on the open end face of the motor housing, piping connection to these supply / discharge ports and openings can be simplified. Similarly, since the opening of the fluid port is arranged on the outer peripheral surface of the rotating frame, the pipe connection to the opening can be easily performed.

Further, since the swash plate type axial piston motor of the type in which the cylinder barrel is fixed and the swash plate is rotated is used for the hydraulic motor, the structure of the rotating part is simplified as compared with the type in which the cylinder barrel is rotated. The cylinder barrel can be used as a part of the motor housing.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a hydraulic motor with a speed reducer according to an embodiment of the present invention.

FIG. 2 is a piping system diagram when the hydraulic motor with a reduction gear is used.

FIG. 3 is a configuration diagram of a conventional hydraulic shovel turning drive device.

FIG. 4 is a configuration diagram of another conventional turning drive device.

[Explanation of symbols]

 Reference Signs List 21 hydraulic motor 22 planetary gear reducer 30 motor housing 31 first housing 32 second housing 32A cylinder barrel 33 third housing 33a open end face 35 output shaft (output member) 36 swash plate Reference Signs List 60 brake mechanism 80 rotary frame 85 rotary joint 100 minute gap 101, 102 peripheral surface 106, 107, 108 oil groove (annular groove) M1, M2 main port (supply / discharge port) S1 first sun Gear (input part) U: internal gear (output part) E1, E2, E3: fluid port F1, F2, F3: fluid port

Claims (3)

[Claims] A swash plate type axial piston type having a supply / discharge port for supplying / discharging a working fluid to an open end surface of a motor housing, and taking out the rotation of a swash plate housed in the motor housing to the outside by an output member. And a planetary gear reducer having an input unit connected to an output member of the hydraulic motor and extracting a reduced output from an internal gear as an output unit, and a rotating frame integrally having the internal gear. Are arranged rotatably on the outer periphery of the motor housing, and the motor housing and the rotating frame are each formed with a peripheral surface facing each other with a small gap when the motor and the rotating frame are relatively rotated, and at least one of the opposed peripheral surfaces is formed. Forming an annular groove continuous in the circumferential direction, one end of the motor housing is communicated with the annular groove,
A fluid port having the other end opened to the open end surface of the motor housing is provided, and a fluid port having one end communicating with the annular groove and the other end opened to the outer peripheral surface of the rotation frame is provided in the rotary frame. And a rotary joint comprising the motor housing and a rotary frame. 2. The hydraulic motor with a speed reducer according to claim 1, wherein said motor housing includes said swash plate therein.
A housing and a second housing integral with a cylinder barrel holding a number of pistons that press against the swash plate;
A third housing integrally connected to the first housing and the second housing with the second housing sandwiched between the first housing and the third housing having an end face exposed to the outside as the open end face; A hydraulic motor with a speed reducer, comprising a brake mechanism for stopping rotation of the swash plate between the outer periphery of the swash plate and the inner periphery of the first housing. 3. The hydraulic motor with a speed reducer according to claim 1, wherein the motor housing includes the swash plate therein.
A housing and a second housing integral with a cylinder barrel holding a number of pistons that press against the swash plate;
A third housing integrally connected to the first housing and the second housing with the second housing sandwiched between the first housing and the third housing having an end face exposed to the outside as the open end face; With a reduction gear, the peripheral surface is formed on an outer periphery of a second housing integrally formed with a cylinder barrel, and a fluid port on the motor housing side is bored in a second housing and a third housing. Hydraulic motor.