JP2021006721A - Hydraulic mechanical continuously variable transmission - Google Patents

Abstract

To provide a hydraulic mechanical continuously variable transmission, in which there are provided a first distribution valve for opening and closing a pump cylinder with respect to a high pressure chamber and a low pressure chamber and a second distribution valve for opening and closing a motor cylinder with respect to the high pressure chamber and the low pressure chamber, and the first distribution valve and the second distribution valve can be smoothly switched.SOLUTION: A first operation unit 53 is engaged with a first support wheel 51, which supports a first distribution valve 42 and is eccentric with respect to an input shaft 3, via a first bearing 52. The first operation unit 53 switchingly operates the first distribution valve 42 via the first bearing 52 and the first support wheel 51 by relative rotation with the first support wheel 51. A second operation unit 58 is engaged with a second support wheel 56, which supports a second distribution valve 43 and is eccentric with respect to the input shaft 3, via a second bearing 57. The second operation unit 58 switchingly operates the second distribution valve 43 via the second bearing 57 and the second support wheel 56 by relative rotation with the second support wheel 56.SELECTED DRAWING: Figure 2

Description

The present invention relates to a hydraulic mechanical continuously variable transmission.

The hydraulic mechanical continuously variable transmission includes the following. A rotating shaft that constitutes either the input shaft or the output shaft, a swash plate type hydraulic pump mounted on one end side of the rotating shaft in the axial direction, and the other end of the rotating shaft in the axial direction. It is equipped with a swash plate type hydraulic motor mounted on the. The hydraulic pump has a pump cylinder block that is non-rotatably supported on a rotating shaft, and pump cylinders that are provided at a plurality of locations in the circumferential direction of the pump cylinder block. The hydraulic motor has a motor cylinder block that is non-rotatably supported by a rotating shaft, and motor cylinders that are provided at a plurality of locations in the circumferential direction of the motor cylinder block. Between the pump cylinder and the motor cylinder, a low pressure chamber connected to each of a plurality of pump cylinders and a plurality of motor cylinders, and a high pressure chamber connected to each of a plurality of pump cylinders and a plurality of motor cylinders. A plurality of first distribution valves that open and close a plurality of pump cylinders separately for each of the high pressure chamber and a low pressure chamber, and a plurality of motor cylinders that open and close each of the high pressure chamber and the low pressure chamber separately. A plurality of second distribution valves are provided. The low-pressure chamber and the high-pressure chamber are provided in a state of rotating together with the pump cylinder block and the motor cylinder block. The plurality of first distribution valves and the plurality of second distribution valves are arranged in the circumferential direction of the pump cylinder block and the motor cylinder block, and rotate together with the pump cylinder block and the motor cylinder block, and the pump cylinder block and the pump cylinder block. It is provided so that it can slide in the direction along the radial direction of the motor cylinder block.

Examples of this type of hydraulically mechanical continuously variable transmission include the continuously variable transmission described in Patent Document 1. The stepless transmission shown in Patent Document 1 is provided with a hydraulic pump and a hydraulic motor provided on an input shaft, a low pressure oil passage as a low pressure chamber, a high pressure oil passage as a high pressure chamber, and the like. A switching spool as one distribution valve is provided, and a switching spool as a second distribution valve is provided.

Japanese Patent No. 6444262

Conventionally, in order to enable the operation of the switching spools as the first distribution valve and the second distribution valve, a ring-shaped guide portion surrounding the ends of a plurality of switching spools in contact with the ends of the switching spools is provided. An operation configuration is adopted in which the switching spool is provided in an eccentric state with respect to the input shaft, and the switching spool is slid by the relative rotation of the guide portion with respect to the switching spool and the eccentricity of the guide portion. In this case, friction is generated between the distribution valve (first distribution valve, second distribution valve) and the guide portion. Further, since the guide portion does not have a function of pulling back the distribution valve, a gap is formed between the distribution valve and the guide portion, and dust easily enters the gap. That is, malfunction of the distribution valve due to friction and dust is likely to occur.

The present invention provides a hydraulic mechanical continuously variable transmission capable of smoothly sliding the first distribution valve and the second distribution valve.

The hydraulic mechanical stepless return device according to the present invention includes a rotating shaft constituting either an input shaft or an output shaft, and a swash plate type hydraulic pump mounted on one end side portion of the rotating shaft in the axial direction. The pump cylinder block is provided with a swash plate type hydraulic motor mounted on the other end side portion of the rotating shaft in the axial direction, and the hydraulic pump is non-rotatably supported by the rotating shaft. The hydraulic motor has a pump cylinder provided at a plurality of locations in the circumferential direction of the pump cylinder block, and the hydraulic motor is a motor cylinder block supported so as not to rotate relative to the rotating shaft, and a plurality of the motor cylinder block in the circumferential direction. A low-pressure chamber having motor cylinders provided at locations and connected to each of the pump cylinders at the plurality of locations and the motor cylinders at the plurality of locations between the pump cylinder and the motor cylinder, and the plurality of pump cylinders. A plurality of high-pressure chambers connected to the pump cylinders at the locations and the motor cylinders at the plurality of locations, and a plurality of positions for opening and closing the pump cylinders at the plurality of locations with respect to the high-pressure chamber and the low-pressure chamber, respectively. A distribution valve and a plurality of second distribution valves for opening and closing the motor cylinders at a plurality of locations with respect to the high pressure chamber and the low pressure chamber are provided, and the low pressure chamber and the high pressure chamber are provided. Is provided so as to rotate together with the pump cylinder block and the motor cylinder block, and the plurality of first distribution valves and the plurality of second distribution valves are provided in the circumferential direction of the pump cylinder block and the motor cylinder block. The pump cylinder block and the motor cylinder block are arranged in a rotating state together with the pump cylinder block and the motor cylinder block, and the pump cylinder block and the motor cylinder block are slidable in the radial direction. A first support wheel that surrounds the ends of the plurality of first distribution valves and is eccentric with respect to the rotation shaft while supporting the ends of the plurality of first distribution valves that are opposite to the rotation shaft side. The body, the first bearing fitted to the outer peripheral portion of the first support wheel body in a state concentric with the first support wheel body, and the outer periphery of the first bearing in a state concentric with the first support wheel body. An annular first operating portion that is fitted to the portion and is rotatably supported relative to the pump cylinder block and slides the first distribution valve via the first bearing and the first supporting wheel body. And, the pump of each of the plurality of second distribution valves A second support wheel body that surrounds the ends of the plurality of second distribution valves and is eccentric with respect to the rotation axis while supporting the ends opposite to the rolling shaft side, and the second support wheel body. The second bearing fitted to the outer peripheral portion of the second support wheel body in a concentric state with, and the motor fitted to the outer peripheral portion of the second bearing in a state concentric with the second support wheel body. An annular second operating portion that is rotatably supported relative to the cylinder block and slides the second distribution valve via the second bearing and the second support wheel is provided.

According to this configuration, the first support wheel body has an operating force to push and pull the first distribution valve by the relative rotation between the first operation unit and the first support wheel body, and the first distribution valve has the first support wheel body. Is pushed and pulled by. Since the first distribution valve is supported by the first support wheel body, no friction is generated between the first distribution valve and the first support wheel body. Since the first support wheel body pulls the first distribution valve, there is no gap between the first distribution valve and the first support wheel body, and dust is generated between the first distribution valve and the first support wheel body. Don't get in. Since the first bearing is interposed between the first support wheel body and the first operation portion, much friction does not occur between the first support wheel body and the first operation portion.

The second support wheel body has an operating force to push and pull the second distribution valve by the relative rotation between the second operation unit and the second support wheel body, and the second distribution valve is pushed and pulled by the second support wheel body. To. Since the second distribution valve is supported by the second support wheel body, no friction is generated between the second distribution valve and the second support wheel body. Since the second support wheel body pulls the second distribution valve, there is no gap between the second distribution valve and the second support wheel body, and dust is generated between the second distribution valve and the second support wheel body. Don't get in. Since the second bearing is interposed between the second support wheel body and the second operation portion, almost no friction is generated between the second support wheel body and the second operation wheel body.

Therefore, the first distribution valve and the second distribution valve can be smoothly slid so as not to cause malfunction due to friction and dust.

In the present invention
The first support wheel body is configured to be able to be divided into two divided first support wheel bodies in a direction along the axis of the rotation shaft, and the two divided first support wheels form the first distribution valve. The first distribution valve is supported by sandwiching the end portion, and the second support wheel body is configured to be divisible into two divided second support wheel bodies in the direction along the axis of the rotation shaft. It is preferable that the second distribution valve is supported by sandwiching the end portion of the second distribution valve between the two split second support wheels.

According to this configuration, the ends of each of the plurality of first distribution valves are formed by applying the two divided first support wheels to the ends of the plurality of first distribution valves from both sides in the axial direction of the rotating shaft. Since the portion is sandwiched between the two divided first support wheels and the ends of the plurality of first distribution valves can be supported by the first support wheels, it is easy to support the first distribution valve by the first support wheels. By applying the two split second support wheels to the ends of the plurality of second distribution valves from both sides in the axial direction of the rotation shaft, the ends of the plurality of second distribution valves are split into two. Since the end portions of the plurality of second distribution valves can be supported by the second support wheel body while being sandwiched by the second support wheel body, the second distribution valve can be easily supported by the second support wheel body.

In the present invention
It is preferable that an electric actuator for rotating the first operation unit is provided.

In this type of hydraulic mechanical stepless transmission, when the power source is stopped and the hydraulic pump is in the shifting state, the hydraulic pump locks in the shifting state. If the power source is restarted while the hydraulic pump is locked in the speed change state, the power source cannot be restarted because the hydraulic mechanical stepless transmission suddenly outputs. According to this configuration, the first operation unit can be rotated and operated by the power of the electric actuator. Therefore, even if the hydraulic pump is locked in the shifting state, the first operating unit is rotated against the lock to shift the hydraulic pump. It is possible to switch from to the neutral state and restart the power source while preventing problems such as sudden output of the hydraulic mechanical continuously variable transmission.

It is a block diagram which shows the power transmission. It is sectional drawing which shows the hydraulic mechanical type continuously variable transmission. It is sectional drawing which shows a part of the 1st operation mechanism and the 2nd operation mechanism. FIG. 2 is a cross-sectional view taken along the line IV-IV of FIG. It is a cross-sectional view of VV of FIG. It is a block diagram which shows the operation structure of the 1st operation part in the 1st operation mechanism provided with another embodiment.

An embodiment of the present invention will be described with reference to the drawings.
The hydraulic mechanical continuously variable transmission 1 is installed in a rice transplanter, a management machine, or the like, and as shown in FIG. 1, the power of a power source 2 such as an engine is input to an input shaft 3, and the input power is a hydraulic type. The continuously variable transmission unit 4 shifts gears, and the shifted power is output from the output shaft 5 to a drive target device 6 such as a traveling device. Specifically, the hydraulic mechanical continuously variable transmission 1 is configured as follows.

As shown in FIG. 2, the hydraulic mechanical continuously variable transmission 1 includes a casing 7 fixed to an airframe frame (not shown) or the like. The input shaft 3 (corresponding to the “rotary shaft” of the configuration of the present invention) is rotatably supported by the pump side portion 7a of the casing 7 and the motor side portion 7b of the casing 7. Specifically, the end portion 3a on the side opposite to the input side of the input shaft 3 is supported by the motor side portion 7b of the casing 7 via the bearing 8. A refueling passage 9 is bored inside the input shaft 3. The oil supply passage 9 is supplied with hydraulic oil by the oil supply pump 10 (see FIG. 1), and supplies the supplied hydraulic oil to the hydraulic pump P and the hydraulic motor M of the continuously variable transmission unit 4.

As shown in FIG. 2, the output shaft 5 has a tubular shape that fits externally into the input shaft 3 and the hydraulic motor M of the stepless speed change unit 4, and has a motor side portion 7b of the casing 7 and a hydraulic motor. It is rotatably supported by the motor cylinder block 30 of M. Specifically, the output side end portion 5a of the output shaft 5 is rotatably supported by the motor side portion 7b of the casing 7 via the bearing 8. The motor side end portion 5b of the output shaft 5 is supported by the motor cylinder block 30 via a bearing 11 so as to be relatively rotatable.

[About hydraulic pump]
As shown in FIG. 2, the continuously variable transmission unit 4 includes a variable displacement type and swash plate type hydraulic pump P and a constant capacity type and sloping plate type hydraulic motor M.
As shown in FIG. 2, the hydraulic pump P is mounted on one end side portion (input side portion) of the input shaft 3 in the axial direction. The hydraulic pump P has a pump cylinder block 20 supported on an input shaft 3 so as not to rotate relative to each other, and a pump swash plate 21 provided at a portion opposite to the hydraulic motor side with respect to the pump cylinder block 20. The pump cylinder block 20 is fitted onto the input shaft 3 by a spline hole, is engaged with the spline portion 3b of the input shaft 3 by the spline hole, and is supported by the input shaft 3 so as not to rotate relative to each other. The pump swash plate 21 is supported by a support portion 7c provided on the casing 7 so that the angle can be changed. Pump cylinders 22 are provided at a plurality of locations in the circumferential direction of the pump cylinder block 20. As shown in FIG. 2, each of the plurality of pump cylinders 22 has a cylinder chamber 22a formed in the pump cylinder block 20 and a piston 22b housed in the cylinder chamber 22a so as to be slidable back and forth. .. The cylinder chamber 22a is formed in a state in which the longitudinal direction is along the axis direction of the input shaft 3. In each of the pump cylinders 22 at a plurality of locations, a spring 23 is provided inside the piston 22b, and the piston 22b is slid-forced to the side exiting the cylinder chamber 22a by the spring 23 and is applied to the pump swash plate 21. ..

[About hydraulic motors]
As shown in FIG. 2, the hydraulic motor M is mounted on the other end side portion (the portion opposite to the input side) of the input shaft 3 in the axial direction. The hydraulic motor M has a motor cylinder block 30 supported on the input shaft 3 so as not to rotate relative to each other, and a motor swash plate 31 provided at a portion opposite to the hydraulic pump side with respect to the motor cylinder block 30. The motor cylinder block 30 and the pump cylinder block 20 are composed of the same block member 13. The motor cylinder block 30 is supported by the input shaft 3 via the pump cylinder block 20 so as not to rotate relative to each other. The motor swash plate 31 is supported by the support portion 5c of the output shaft 5 so that the angle cannot be changed. Motor cylinders 32 are provided at a plurality of locations in the circumferential direction of the motor cylinder block 30. The number of installed motor cylinders 32 is the same as the number of installed pump cylinders 22. As shown in FIG. 2, each of the plurality of motor cylinders 32 has a cylinder chamber 32a formed in the motor cylinder block 30 and a piston 32b housed in the cylinder chamber 32a so as to be slidable back and forth. .. The cylinder chamber 32a is formed in a state in which the longitudinal direction is along the axis direction of the input shaft 3. In each of the motor cylinders 32 at the plurality of locations, a spring 33 is provided inside the piston 32b, and the piston 32b is slidly urged to the side exiting the cylinder chamber 32a by the spring 33 and applied to the motor swash plate 31. ..

[About low pressure chamber, high pressure chamber, first distribution valve, second distribution valve]
As shown in FIG. 2, between the pump cylinder 22 and the motor cylinder 32, in detail, between the pump cylinder group having a plurality of pump cylinders 22 and the motor cylinder group having a plurality of motor cylinders 32. The low pressure chamber 40, the high pressure chamber 41, the same number of first distribution valves 42 as the number of installed pump cylinders 22, and the same number of second distribution valves 43 as the number of installed motor cylinders 32 are provided. The low pressure chamber 40, the high pressure chamber 41, the plurality of first distribution valves 42, and the plurality of second distribution valves 43 are provided in a state of rotating together with the pump cylinder block 20 and the motor cylinder block 30. Specifically, the pump cylinder block 20 and the motor cylinder block 30 are composed of the same block member 13. The low pressure chamber 40, the high pressure chamber 41, the plurality of first distribution valves 42, and the plurality of second distribution valves 43 are the pump cylinder group and the motor among the block members 13 that rotate together with the pump cylinder block 20 and the motor cylinder block 30. It is provided in a portion located between the cylinder group.

As shown in FIGS. 2 and 4, the low pressure chamber 40 is formed in an annular shape on the outer side of the input shaft 3. The high pressure chamber 41 is formed in an annular shape on the outer side in the radial direction of the input shaft from the low pressure chamber 40. First valve holes 44 are provided at a plurality of locations in the circumferential direction of the block member 13 so that the low pressure chamber 40 and the high pressure chamber 41 communicate with each other. The first valve holes 44 at a plurality of locations are arranged radially in the circumferential direction of the pump cylinder block 20 in a state where one first valve hole 44 corresponds to one pump cylinder 22. Each of the first valve holes 44 at a plurality of locations is connected to the cylinder chamber 22a of the corresponding pump cylinder 22 by a first communication passage 45. As shown in FIGS. 2 and 5, the second valve is in a state where the low pressure chamber 40 and the high pressure chamber 41 communicate with each other at a plurality of locations in the circumferential direction of the block member 13 on the hydraulic motor side of the first valve hole 44. A hole 46 is provided. The second valve holes 46 at a plurality of locations are arranged radially in the circumferential direction of the motor cylinder block 30 in a state where one second valve hole 46 corresponds to one motor cylinder 32. Each of the second valve holes 46 at a plurality of locations is connected to the cylinder chamber 32a of the corresponding motor cylinder 32 by a second passage 47.

The low pressure chamber 40 is connected to each of the plurality of pump cylinders 22 via a first valve hole 44 and a first communication passage 45, and is connected to each of the plurality of motor cylinders 32 via a second valve hole 46 and a second communication passage 45. It is connected via 47. The high-pressure chamber 41 is connected to each of the plurality of pump cylinders 22 via a first valve hole 44 and a first communication passage 45, and is connected to each of the plurality of motor cylinders 32 via a second valve hole 46 and a second communication passage 45. It is connected via 47.

As shown in FIGS. 2 and 4, the plurality of first distribution valves 42 are distributed into the plurality of first valve holes 44 and are fitted into the first valve holes 44 so as to be reciprocally slidable. The plurality of first distribution valves 42 are arranged radially in the circumferential direction of the pump cylinder block 20 and are slidably supported in the radial direction of the pump cylinder block 20. Each of the plurality of first distribution valves 42 opens and closes the first valve hole 44 with respect to the low pressure chamber 40 and opens and closes the first valve hole 44 with respect to the high pressure chamber 41 by sliding operation. The corresponding pump cylinder 22 is opened and closed with respect to the low pressure chamber 40, and the corresponding pump cylinder 22 is opened and closed with respect to the high pressure chamber 41.

As shown in FIGS. 2 and 5, the plurality of second distribution valves 43 are distributed into the plurality of second valve holes 46 and are fitted into the second valve holes 46 so as to be reciprocally slidable. The plurality of second distribution valves 43 are arranged radially in the circumferential direction of the motor cylinder block 30 and are slidably supported in the radial direction of the motor cylinder block 30. Each of the plurality of second distribution valves 43 opens and closes the second valve hole 46 with respect to the low pressure chamber 40 and opens and closes the second valve hole 46 with respect to the high pressure chamber 41 by sliding operation. The corresponding motor cylinder 32 is opened and closed with respect to the low pressure chamber 40, and the corresponding motor cylinder 32 is opened and closed with respect to the high pressure chamber 41.

As shown in FIG. 2, a first operation mechanism 50 for switching and operating the plurality of first distribution valves 42 is provided over the plurality of first distribution valves 42 and the pump side portion 7a of the casing 7. As shown in FIGS. 2 and 3, the first operating mechanism 50 includes a first support wheel body 51 and a first support wheel body 51 that surround end portions 42a on the side opposite to the input shaft side of the plurality of first distribution valves 42. The first bearing 52 fitted to the outer peripheral portion of the first support wheel body 51 in a concentric state with, and the annular first bearing 52 fitted to the outer peripheral portion of the first bearing 52 in a concentric state with the first support wheel body 51. 1 The operation unit 53 is provided. The first bearing 52 is formed by the inner ring 52a surrounding the first support wheel 51, the outer ring 52b fitted in the first operation unit 53, and the inner ring 52a and the outer ring 52b sandwiched between the inner ring 52a and the outer ring 52b. It has a sphere 52c provided between them. The first bearing 52 is a so-called ball bearing. As the first bearing 52, a needle bearing can be adopted.

The end 42a of each of the plurality of first distribution valves 42 is supported by the first support wheel 51. To support the end portion 42a of the first distribution valve 42 on the first support wheel body 51, as shown in FIGS. 2 and 3, the first support wheel body 51 is two in the direction along the axis of the input shaft 3. It is configured to be divisible into two divided first support wheel bodies 51a, and is performed by sandwiching the end portion 42a of the first distribution valve 42 by two divided first support wheel bodies 51a. The first support wheel 51 is supported by the block member 13 via the first distribution valve 42 in a state of being eccentric with respect to the input shaft 3, and rotates together with the pump cylinder block 20. The first operating portion 53 is integrally formed at a portion of the pump-side portion 7a of the casing 7 located outside the block member 13, and is fixed to the casing 7. In the present embodiment, the first operation unit 53 is integrally molded with the casing 7, but the present invention is not limited to this. The first operation unit 53 may be manufactured as a member separate from the casing 7 and supported by the casing 7 by being attached to the casing 7.

In the first operation mechanism 50, when the pump cylinder block 20 rotates, a relative rotation occurs between the first support wheel body 51 and the first operation unit 53, and this relative rotation and the first support wheel body 51 Due to the eccentricity with respect to the input shaft 3, the plurality of first distribution valves 42 are pushed and pulled by the first support wheel 51. That is, the first operation unit 53 slides the plurality of first distribution valves 42 via the first bearing 52 and the first support wheel body 51.

As shown in FIG. 2, a second operation mechanism 55 for switching and operating the plurality of second distribution valves 43 is provided over the plurality of second distribution valves 43 and the output shaft 5. As shown in FIGS. 2 and 3, the second operation mechanism 55 includes a second support wheel body 56 and a second support wheel body 56 that surround the end 43a on the side opposite to the input shaft side of the plurality of second distribution valves 43. The second bearing 57 fitted to the outer peripheral portion of the second support wheel 56 in a concentric state with, and the annular first fitted to the outer peripheral portion of the second bearing 57 in a concentric state with the second support wheel 56. 2 The operation unit 58 is provided. The second bearing 57 is formed by the inner ring 57a surrounding the second support wheel 56, the outer ring 57b fitted in the second operation portion 58, and the inner ring 57a and the outer ring 57b sandwiched by the inner ring 57a and the outer ring 57b. It has a sphere 57c provided between them. The second bearing 57 is a so-called ball bearing. As the second bearing 57, a needle bearing can be adopted.

The end 43a of each of the plurality of second distribution valves 43 is supported by the second support wheel 56. To support the end 43a of the second distribution valve 43 on the second support wheel 56, as shown in FIGS. 2 and 3, the second support wheel 56 is two in the direction along the axis of the input shaft 3. It is configured to be divisible into two divided second support wheel bodies 56a, and is performed by sandwiching the end portion 43a of the second distribution valve 43 by the two divided second support wheel bodies 56a. The second support wheel 56 is supported by the block member 13 via the second distribution valve 43 in an eccentric state with respect to the input shaft 3, and rotates together with the motor cylinder block 30. The second operation unit 58 is integrally formed at a portion of the output shaft 5 located outside the block member 13 and is fixed to the output shaft 5. The second operation unit 58 rotates together with the output shaft 5. In the present embodiment, the second operation unit 58 is integrally molded with the output shaft 5, but is not limited to this. The second operation unit 58 may be manufactured as a member separate from the output shaft 5 and supported by the output shaft 5 by being attached to the output shaft 5.

In the second operation mechanism 55, when the motor cylinder block 30 rotates, a relative rotation occurs between the second support wheel 56 and the second operation unit 58, and this relative rotation and the second support wheel 56 Due to the eccentricity with respect to the input shaft 3, the plurality of second distribution valves 43 are pushed and pulled by the second support wheel 56. That is, the second operation unit 58 slides the plurality of second distribution valves 43 via the second bearing 57 and the second support wheel 56.

As shown in FIGS. 2, 4 and 5, a charge chamber 60 is provided inside the low pressure chamber 40. Pressure oil is supplied to the charge chamber 60 by the oil supply passage 9, and each of the plurality of first distribution valves 42 is slidably urged toward the first support wheel 51 by the pressure oil of the charge chamber 60, and the plurality of second distributions are distributed. Each of the valves 43 is slidably urged toward the second support wheel 56 by the pressure oil in the charge chamber 60.

When power is input to the input shaft 3, the pump cylinder block 20 is rotated by the input shaft 3, the plurality of pump cylinders 22 perform discharge operation and suction operation, and the motor cylinder block 30 is rotated by the input shaft 3. A plurality of motor cylinders 32 perform discharge operation and suction operation. When the pump cylinder block 20 is rotated, the relative rotation between the first support wheel 51 and the first operation unit 53 is generated, the first operation mechanism 50 is operated, and the plurality of first distribution valves 42 are first operated. The plurality of pump cylinders 22 are slidably operated by the mechanism 50 and opened and closed with respect to each of the low pressure chamber 40 and the high pressure chamber 41 by the corresponding first distribution valve 42. When the motor cylinder block 30 is rotated, the relative rotation between the second support wheel 56 and the second operation unit 58 is generated, the second operation mechanism 55 is operated, and the plurality of second distribution valves 43 are second-operated. The plurality of pump cylinders 22 are slidably operated by the mechanism 55 and opened and closed with respect to each of the low pressure chamber 40 and the high pressure chamber 41 by the corresponding second distribution valve 43. As a result, the hydraulic oil is discharged to the high-pressure chamber 41 by the pump cylinder 22 in which the hydraulic pump P is discharged, and the hydraulic oil is sucked from the high-pressure chamber 41 by the motor cylinder 32 in which the hydraulic motor M is suction-operated. The hydraulic oil is discharged to the low pressure chamber 40 by the discharge-operated motor cylinder 32, and the hydraulic oil is sucked from the low-pressure chamber 40 by the pump cylinder 22 which is suction-operated by the hydraulic pump P. As a result, the continuously variable transmission 4 performs a shift operation, the power of the input shaft 3 is changed by the continuously variable transmission 4 to the power of the rotation speed corresponding to the angle of the pump diagonal plate 21, and the changed power is the output shaft. It is output from 5.

[Another Embodiment]
(1) FIG. 6 is a schematic view showing a first operation mechanism 50 including another embodiment. In the first operation mechanism 50 including another embodiment, the first operation unit 53 is rotatably supported by the casing 7. The operation mechanism 61 that rotates the first operation unit 53 is linked to the first operation unit 53, and the electric actuator 62 that drives the operation mechanism 61 is linked to the operation mechanism 61.

The operation mechanism 61 is configured by using a worm gear or the like that can lock the first operation unit 53 to a predetermined rotation position. When the operation mechanism 61 is driven by the electric actuator 62, the first operation unit 53 is rotated, and when the drive by the electric actuator 62 is stopped, the rotation operation of the first operation unit 53 is stopped and the first operation is performed. The unit 53 is locked at the stopped position.

When power is input to the input shaft 3 and the continuously variable transmission unit 4 shifts, the first operation unit 53 is fixed by the operation mechanism 61 at a rotation position where the switching operation of the first distribution valve 42 is appropriately performed. When the power source 2 is stopped and the input to the input shaft 3 is stopped, if the continuously variable transmission 4 is in the shifting state, the continuously variable transmission 4 is locked in the shifting state. In this case, the operation mechanism 61 is driven by the electric actuator 62 to rotate the first operation unit 53, and the hydraulic pump P is switched from the shift state to the neutral state. Then, even if the power source 2 is restarted, the power source 2 can be restarted while preventing the hydraulic mechanical continuously variable transmission 1 from suddenly outputting.

(2) In the above embodiment, an example in which the hydraulic pump P and the hydraulic motor M are mounted on the input shaft 3 is shown, but the present invention is not limited to this. That is, the hydraulic pump P and the hydraulic motor M may be mounted on the output shaft. That is, the hydraulic pump P and the hydraulic motor M may be mounted on the rotating shaft constituting either the input shaft or the output shaft.

(3) In the above-described embodiment, an example in which the variable displacement hydraulic pump P and the constant displacement hydraulic motor M are adopted is shown, but the present invention is not limited to this. For example, a constant-variable-capacity hydraulic pump P and a variable-capacity hydraulic motor M are adopted, or a variable-capacity hydraulic pump P and a variable-capacity hydraulic motor M are adopted. May be good.

(4) In the present embodiment, seven pump cylinders 22 and seven motor cylinders 32 are provided, but the present invention is not limited to this. Six or less, or eight or more pump cylinders 22, six or less, or eight or more motor cylinders 32 may be provided.

The present invention includes a swash plate type hydraulic pump and a swash plate type hydraulic motor mounted on a rotating shaft that constitutes either an input shaft or an output shaft, and a low pressure chamber is provided between the pump cylinder and the motor cylinder. The high pressure chamber, the first distribution valve, and the second distribution valve are provided, the low pressure chamber and the high pressure chamber are provided in a state of rotating together with the pump cylinder block and the motor cylinder block, and the first distribution valve and the second distribution valve are provided. , Arranged in the circumferential direction of the pump cylinder block and the motor cylinder block, rotating together with the pump cylinder block and the motor cylinder block, and slidable in the radial direction of the pump cylinder block and the motor cylinder block. It can be applied to various hydraulic mechanical stepless transmissions provided in.

3 Rotation axis (input axis)
20 Pump cylinder block 22 Pump cylinder 30 Motor cylinder block 32 Motor cylinder 40 Low pressure chamber 41 High pressure chamber 42 1st distribution valve 42a End 43 2nd distribution valve 43a End 51 1st support wheel 51a Divided 1st support wheel 52 1st bearing 53 1st operation part 56 2nd support wheel body 56a Split 2nd support wheel body 57 2nd bearing 58 2nd operation part 62 Electric actuator P Hydraulic pump M Hydraulic motor

Claims (3)

A rotating shaft that constitutes either the input shaft or the output shaft,
A swash plate type hydraulic pump mounted on one end side of the rotating shaft in the axial direction,
A swash plate type hydraulic motor mounted on the other end side portion of the rotating shaft in the axial direction is provided.
The hydraulic pump has a pump cylinder block that is non-rotatably supported on the rotating shaft, and pump cylinders that are provided at a plurality of locations in the circumferential direction of the pump cylinder block.
The hydraulic motor has a motor cylinder block that is non-rotatably supported on the rotating shaft, and motor cylinders that are provided at a plurality of locations in the circumferential direction of the motor cylinder block.
Between the pump cylinder and the motor cylinder, a low pressure chamber connected to each of the pump cylinders at a plurality of locations and the motor cylinders at the plurality of locations, and the pump cylinders at the plurality of locations and the plurality of locations. A high-pressure chamber connected to each of the motor cylinders, a plurality of first distribution valves for opening and closing the pump cylinders at the plurality of locations separately for each of the high-pressure chamber and the low-pressure chamber, and the motors at the plurality of locations. A plurality of second distribution valves for opening and closing the cylinder separately for each of the high pressure chamber and the low pressure chamber are provided.
The low-pressure chamber and the high-pressure chamber are provided in a state of rotating together with the pump cylinder block and the motor cylinder block.
A state in which the plurality of first distribution valves and the plurality of second distribution valves are arranged in the circumferential direction of the pump cylinder block and the motor cylinder block, and rotate together with the pump cylinder block and the motor cylinder block. Moreover, it is provided so as to be slidable in the radial direction of the pump cylinder block and the motor cylinder block.
A first support that surrounds the ends of the plurality of first distribution valves and is eccentric with respect to the rotation shaft while supporting the ends of the plurality of first distribution valves that are opposite to the rotation shaft side. The ring body, the first bearing fitted to the outer peripheral portion of the first support wheel body in a state concentric with the first support wheel body, and the first bearing in a state concentric with the first support wheel body. An annular first operation that is fitted to the outer peripheral portion and is rotatably supported relative to the pump cylinder block, and slides the first distribution valve via the first bearing and the first support wheel body. With a part,
A second support that surrounds the ends of the plurality of second distribution valves and is eccentric with respect to the rotation shaft while supporting the ends of the plurality of second distribution valves that are opposite to the rotation shaft side. The wheel body, the second bearing fitted to the outer peripheral portion of the second support wheel body in a state concentric with the second support wheel body, and the second bearing in a state concentric with the second support wheel body. An annular second operation that is fitted to the outer peripheral portion and is rotatably supported relative to the motor cylinder block, and slides the second distribution valve via the second bearing and the second support wheel body. A hydraulic mechanical stepless speed changer equipped with a bearing. The first support wheel body is configured to be able to be divided into two divided first support wheel bodies in a direction along the axis of the rotation shaft, and the two divided first support wheels form the first distribution valve. The first distribution valve is supported by sandwiching the end portion.
The second support wheel body is configured to be able to be divided into two divided second support wheel bodies in a direction along the axis of the rotation shaft, and the two divided second support wheels form the second distribution valve. The hydraulic mechanical continuously variable transmission according to claim 1, wherein the second distribution valve is supported by sandwiching the end portion. The hydraulic mechanical continuously variable transmission according to claim 1 or 2, further comprising an electric actuator for rotating the first operation unit.

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