JPS61165065A - Hydraulic speed changer - Google Patents

Abstract

PURPOSE:To regulate the speed change ratio of hydraulic speed changer freely by providing a rack on the back of an inclined board of a bent axis type axial plunger pump in a hydraulic type speed changer while rotating a pinion gearing with said rack. CONSTITUTION:Supply/discharge paths 12, 13 for supplying/discharging fluid into a cylinder 20 are formed in an inclined board 10 sliding against a cylinder block 9 provided in a bent axis type axial plunger pump of hydraulic type speed changer. A rack 31 is formed along the inclining direction of the inclined board on the back of the inclined board 10 while a pinion 32 gearing with said rack 31 is provided in the housing 35. An operating rod is provided continuously to the pinion 32 and rolled to vary the inclination angle of the inclined board thus to vary the speed change ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a hydraulic transmission configured by pairing a hydraulic pump and a hydraulic motor.

[Prior Art] For example, in the transmission of an agricultural tractor, a hydraulic pump and a hydraulic motor are paired, the hydraulic pump is driven by engine power, etc., and the hydraulic motor is driven by the pressure fluid supplied by the pump! %, and the capacity of the pump and/or motor is varied to steplessly change the rotational input of the pump and the rotational output from the motor. The use of is attracting attention.

Currently, axial piston-type hydraulic pumps or motors are commonly used in this type of transmission, but in such conventional transmissions, both the pump and the motor have a torque-hydraulic pressure relationship. It has a fatal drawback of poor conversion efficiency, and this is the biggest factor preventing the widespread use of hydraulic transmissions. In other words, axial piston type pumps/motors, whether they are slant plate type or oblique shaft type, operate by mutually converting the hydraulic pressure of the rotating car through the reciprocating motion of the piston. At this time, in existing pumps/motors, each component phase, including the outer circumferential surface of each piston and the inner circumferential surface of the cylinder pore that fits the piston, is important. Mechanical friction on the sliding surface between il' is extremely large, and energy loss due to this friction causes a significant reduction in conversion efficiency.

In addition, in conventional hydraulic transmissions, the akinyal piston type pump/motor that constitutes the pump and motor is
There is no suitable device that can be attached to a motor to quickly and accurately perform variable capacity operation, and as a result, the speed change range and speed change pattern that can actually be used are limited. In other words, even when diversity in speed change conditions is required, it has not been possible to adequately meet this requirement.

[Problems to be Solved by the Invention] The present invention has been made by focusing on the problems of the prior art, and its purpose is to improve hydraulic pressure that can minimize energy loss. Hydraulic converter combines a pump and a hydraulic motor and has much higher power transmission efficiency than conventional ones, and is equipped with a simple variable capacity mechanism that allows the speed change pattern to be varied in a variety of ways. The goal is to provide equipment.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a hydraulic pump and a hydraulic motor that form a pair, and an outflow port of the pump and an inflow port of the motor. The inlet port of the pump and the outlet port of the motor are communicated with each other, and the capacity of the pump and/or the motor is varied to steplessly change the speed of the rotational input of the pump, so that the motor is connected to the inlet port of the pump. The transmission device is configured to output rotation from the pump and the motor, in which both the pump and the motor are housed in a housing having an inflow and outflow port, and a rotating shaft for human output supported by the housing, and a rotating shaft for human output supported by the housing, and a rotating shaft for human output supported by the housing, and a rotating shaft for human output supported by the housing A torque plate is provided to be integrally rotatable, and a plurality of cylindrical holes are provided to be rotatable around an inclined axis that intersects with the rotation center of the torque plate, and are parallel to the inclined axis. a plurality of pistons that are slidably fitted into each cylinder hole of the cylinder block and whose outer ends on the side opposite to the cylinder block are pivotally supported on the torque plate; With the inflow and outflow ports and each cylinder hole? a pulp surface having a connection port for connection, and a housing or tilting plate that slides between the cylinder blower 7 and the cylinder block between the outer end of each piston and the torque plate; A pressure pocket for introducing hydraulic fluid is provided between the torque plate and the housing that slides on the torque plate, respectively, so that the piston, the cylinder block, and the torque plate can be statically balanced in the axial direction. The pump is configured of an axial piston pump/motor, and is arranged to be tiltable with respect to the torque plate on at least one of the oblique axial piston pump/motor that constitutes the hydraulic pump and the hydraulic motor. and the tilting plate on which the cylinder block slides relative to each other so as to be freely rotatable and integrally tiltable; The present invention is characterized in that a variable capacity mechanism is provided, which includes a pinion that meshes with a tooth profile carved in the groove, and an operating shaft that rotates the pinion.

[Operation] In a hydraulic transmission with such a configuration, both the hydraulic pump and the hydraulic motor statically balance the axial hydraulic pressures acting on the cylinder block, piston, and torque plate. First of all,
In addition, the hydraulic pressure of the hydraulic fluid is combined in the pressure pocket provided between the outer end of the piston and the couple applied to the torque plate balances the input and output torque of the torque plate. It is possible to reduce friction caused by a falling moment acting on the piston, causing the piston to rub against the inner circumferential surface of the cylinder hole, or by pressing the outer end of each piston against the torque plate. Second, between the cylinder block and the housing or tilting member that slides on it, and between the torque plate and the housing that meshes with it, there is a liquid film of hydraulic fluid that supports them in the axial direction. Since it is supported, friction at these sliding parts can be effectively reduced. For this reason, energy loss due to mechanical friction in both the hydraulic pump and hydraulic motor that make up the transmission is extremely small, and this hydraulic transmission can therefore have extremely high power transmission efficiency as a whole. be. In addition, in this hydraulic transmission, the capacity of the hydraulic pump or hydraulic motor is changed by changing the inclination angle of the cylinder block in conjunction with the tilting of the tilting plate by rotating the pinion. , such a variable capacity mechanism is compact and has a simple structure, and at the same time, it can instantly change the inclination angle of the cylinder block to the desired value by following the rotation of the pinion regardless of its rotational drive means. can be precisely controlled. In other words, the capacity of the hydraulic pump or hydraulic motor can be freely adjusted and varied in response to the rotational operation of the pinion, and therefore a variety of speed change patterns can be easily applied to the transmission device depending on its purpose. Another feature is that it can.

[Example] Hereinafter, five embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing a configuration example of a hydraulic transmission according to the present invention, in which a pair of hydraulic pump PE and hydraulic motor IIE are installed inside a case. A valve with the required hydraulic fluid circuit drilled inside the rear cover (
Adapter) They are joined in series with the blocks BB interposed and abutted against each other. An input shaft I is connected to one hydraulic pump PE, and an output shaft I is connected to the other hydraulic motor E.
are connected. This hydraulic pump ρE and hydraulic motor 1
Although not shown, each of 4E has an outflow (discharge) port and an inflow (suction) port on the valve block 8B side, and the valve block 8B has an outflow (discharge) port and an inflow (suction) port. The outflow port of the hydraulic pump PE and the inflow port of the hydraulic motor ME are communicated, and the inflow port of the hydraulic pump PE and the outflow port of the hydraulic motor ME are communicated. As shown in FIG. 3, the schematic configuration includes: a high pressure circuit H that communicates an outflow port of the hydraulic pump PH with an inflow port of the hydraulic motor;
A low pressure circuit that communicates the inflow port of the hydraulic pump PE with the outflow port of the hydraulic motor ME, and an unload circuit that directly connects these high and low pressure circuits H and L through relief valves R and R. Consists of A, A, etc.

The hydraulic pump PE and hydraulic motor E constituting this hydraulic transmission are both variable displacement oblique shaft type piston pumps/motors having a common configuration. Therefore, based on the configuration of the hydraulic pump PE, which will be enlarged and disclosed as the second factor, the internal configuration thereof will be described in detail below.

:Figure 52 shows the hydraulic pump PE (or hydraulic motor ME).
), and numeral 1 in the figure is a housing housing the components. This housing l consists of a front cover 2 forming a hollow cylindrical body, and a carrier cover 3 that is liquid-tightly attached to the rear end opening of the front cover 2, and has the outflow port and the inflow port on the rear cover 3 side. The rotating shaft 4 is accommodated in the housing l, which is open (none of which is shown).

This rotating shaft 4 is cantilever-supported by the housing 1 via a two-piece radial bearing 5.6 on the front cover 2 side, and is passed through an opening provided in the front cover 2 at its outer end. In the example shown in FIG. 1, the input shaft load (or output shaft 2) is connected to this rotary shaft 4. Further, a spline groove is formed in a midway portion of the rotating shaft 4 located inside the housing 1, and the torque plate 7 is spline-fitted to this portion. The torque plate 7 is in the shape of a disc and rotates together with the rotating shaft 4. This torque plate 7 has its bore 1 end face in close contact with a stepped wall (pressure receiving surface) 8 formed inside the front cover 2 in a direction perpendicular to the rotating shaft 4 and whose contact portion is finished flush. 8 and is slidably rotated freely. A cylinder block 9 is disposed behind the torque plate 7. The cylinder block 9 has a cylindrical shape that is inclined within a relatively small predetermined angle range with respect to the rotation center M of the torque plate 7 and the rotating shaft 4, and its axis is set as the inclined axis. (The figure shows a neutral state where L matches M, that is, a no-output state). Then, the rear end surface of this cylinder block 9 forms a pulp surface 11 having a connection port 12, 13, and a tilting plate 10 disposed in the housing 1 for tilting the cylinder block 9, as will be described later. It is slidably rotated on the front end surface. That is, in this pump/motor, in order to connect the inflow and outflow ports (not shown) provided on the rear cover 3 side of the housing 1 and the piston inner chamber 20 formed in each cylinder hole 14 of the cylinder block 9. Connection port 12.
A valve surface 11 having a diameter of 13 is provided on the front end surface of a tilting plate 10 on which the rear end surface of the cylinder block 9 slides. Then, as shown in FIG. 4, this valve surface 1
1, the connection ports 12, 13 each have a semicircular arc shape and are open to the front end surface of the tilting member 51110, and under relative rotation with the cylinder block 9, each of the hydraulic fluid flow passages 14a
A distributor that communicates the piston internal chamber 20 present in one side region with the outflow port (connection port 12) and communicates the piston internal chamber 20 present in the opposite region with the inflow port (connection port 13) through the T- I am trying to make it work. Note that each connection port 12.
13 is a branching and merging path 12a bored in the inclined fig.
, 13a and a communication passage 12b bored in the housing 1 slidably associated with the flow passages 12a, 13a;
It is in one-to-one communication with the outflow and inflow ports via the port 13b. The cylinder protrusion 9 is provided with a plurality of cylinder holes 14 that are parallel to the inclined axis thereof and open toward the torque plate 7 at equal angular intervals in the circumferential direction. Pistons] 5 are slidably fitted into the cylinder holes 14. The piston 15 includes a piston body 16 that narrowly fits into the cylinder hole 14, a rod portion 17 extending outward from the piston body 16, and a rod portion 17 formed at the outer end thereof. It is formed integrally with the spherical end portion 18,
The main body 16 is fitted into the inner periphery of the cylinder hole 14 with an appropriate gap (approximately 0.05 mm recommended). and,
Spherical end portions 18 provided at the outer ends of these pistons 15 are each pivoted to the torque plate 7 for rotation. That is, the same number of spherical seats 19 as the pistons 15 are provided on the rear end surface of the torque plate 7 at equal angular intervals in the circumferential direction, and each spherical seat 19 has a spherical end portion of each piston 15. 18 are fitted in close sliding contact. The piston inner chamber 20 is formed in each cylinder hole 14 which is closed by the main body 16 on the inner end side of the piston 15.

Note that 21 is a piston retainer for preventing the piston spherical end portion 18 from separating from the spherical seat 19;
23 is a synchronous connecting rod for synchronously rotating the torque plate 7 and the cylinder block 9, and 23 is interposed in a space between the opposing torque plate 7 and cylinder block 9 to allow the two to slide together. It is a spring that presses against the surface 8.11.

In this piston pump or motor, the fitting length of the piston 15 into the cylinder hole 14 is set to l.
The center of rotation M is set to a small value of about am.
The angle range of the tilted axis is 15° or less,
Preferably, it is set in a range of 100 or less (in the following description, this inclination angle will be expressed as θ).

The hydraulic pump PE (and the hydraulic motor E), which is composed of a diagonal piston/motor having the basic configuration as described above, further includes the piston 15, the cylinder blower 7, and the torque. The plates 7 are each statically balanced so that at least the forces that press these members in the axial direction are balanced. That is, for this purpose, a first pressure pocket 7 (the connection port 12.1) is first formed between the valve face 11 and the cylinder block 9.
3), and a second pressure pocket 24 is formed between the outer end (spherical end) 18 of the piston 15 and the torque plate 7 (spherical seat 19), The pressure pocket 24 of each piston 15 is connected to the piston inner chamber 20 through a hydraulic fluid introduction passage 14b formed in the axial center of each piston 15.
A portion of the hydraulic fluid inside is introduced. and,
The hydraulic fluid in the first pressure pocket 12 presses the cylinder block 9 in the direction of the torque plate 7, and the hydraulic fluid in the piston inner chamber 20 presses the cylinder block 9 in the direction of the valve surface 11. The hydraulic fluid in the second pressure pocket 24 pushes the piston 15 toward the cylinder block 9, and the hydraulic fluid in the piston inner chamber 20 pushes the piston 1 toward the cylinder block 9.
5 in the direction of the torque plate 7 is approximately balanced. Specifically, by setting the opening width wl of one of the connection ports 12 constituting the first pressure pocket and the width W2 of the sliding surface between the valve surface 11 and the cylinder block 9 to appropriate values. , the force F1 with which the hydraulic fluid presses the rear end surface of the cylinder block 9 is set to a desired value (see FIG. 6);
The hydraulic balance for 5 is as follows. That is,
an annular groove 25 is provided in the spherical end 18 of the piston 15;
The second pressure pocket 2 is formed by this annular groove 25 and a concave portion 26 provided in the spherical seat 19 in communication with the annular groove 25.
4 is formed. The hydraulic fluid in this pressure pocket 24 presses the piston 15 in the direction of the cylinder block 9 with a force F3, and the hydraulic fluid in the piston inner chamber 20 presses the piston 15 in the direction of the torque plate 7 with a force F'. I try to keep the balance between 2 and 2 (7th
(see figure), and the hydraulic pressure is balanced for the torque plate 7 as follows. That is, a third pressure pocket 27 is formed between the front end surface of the torque plate 7 and the pressure receiving surface 8 of the housing l to which this surface is in close contact, into which the hydraulic fluid in the piston inner chamber 20 is introduced. The structure is such that the thrust force of the hydraulic fluid in the pressure pocket 27 pressing the torque plate 7 and the thrust force acting on the torque plate 7 from the piston 15 side are substantially balanced. Specifically, portions of the front end surface of the torque plate 7 corresponding to the respective spherical receiving seats 19 are made to protrude in a circular shape, and the protruding surface 28 is brought into close contact with the pressure receiving surface 8 provided on the front cover 2. A pressure pocket 27 having a shape as shown in FIG. 5 is provided on this protruding surface 28, and a part of the hydraulic fluid is introduced into the piston inner chamber 20 through a pressure fluid introduction passage 29 into this pressure pocket 27. ing. Then, there is a force F4 in which the hydraulic fluid in the pressure pocket 27 presses the torque plate 7 in the direction of the piston 15, and a force F' in which the hydraulic fluid in the pressure pocket 24 presses the torque plate 7 in the direction of the pressure receiving surface 8. 3 thrust direction acid content F' 3 c.

I try to balance Sθ (see Figure 8).
.

Discard the cylinder block 9. The piston 15 and the torque plate 7 are each statically balanced.

Further, this hydraulic pump PE (as well as the hydraulic motor ME) is provided with the following variable capacity mechanism 30 along with its operating mechanism. To explain the configuration of this variable capacity mechanism 30, this mechanism 30 is arranged in the housing 1 as a tilting member for tilting the cylinder pro 9, and the tilting plate itself is tiltable around a predetermined tilting center. 1°, and a pinion 32 that is disposed on the rear side of the tilting plate 10 opposite to the cylinder block 9 and meshes with a tooth profile 31 carved along the arcuate surface 10B formed on the rear surface of the tilting plate 11i10. and an operating shaft 33 that rotates the pinion 32. Specifically, the tilting plate 1o has the rear end surface of the cylinder block 9 slidably connected to the valve surface 11 on the front end surface thereof, and
The inner circumferential surface of the cylinder block 9 is brought into sliding contact with the guide ring 34 fitted and projected from the front end of the cylinder block 9, so that the axis of the cylinder block 9 is aligned with the axis of the tilting plate 10. 9 is designed to tilt integrally with this tilting plate lO. This tilting plate IO has large diameter arcuate surfaces IOA on both sides and a small diameter arcuate surface 10 in the center on its back surface.
The concave surface 36 of the support block 35 has a large diameter arcuate surface 10A fixed to the inner surface of the housing l.
It is allowed to freely tilt around a predetermined tilting center 0 while sliding on the concave surface 36. Further, the tooth profile 31 in a direction perpendicular to the circular arc is carved in a band shape on the small diameter circular arc surface 10B formed at the center of the back surface of the tilting plate 10, and the tilting plate lO facing this tooth profile 31 The pinion 32 that meshes with the tooth profile 31 is arranged on the back side of the gear. The operating shaft 33 that rotates the pinion 32 is connected to the axial center of the pinion 32.

An operating mechanism for varying the capacities of the hydraulic pump PE and the hydraulic motor ME by the rotational movement of the pinion 32 via the operating shaft 33 will be described with reference to FIGS. 1 and 3. In this case, the operating shaft 33. is connected to each pinion 32° 32 on the hydraulic motor ME side and the hydraulic pump PE side.
33 extends from the housing l to the outside through the case K, and has at its end a gearshift operating shaft for rotating the operating shaft 33 and 33 by tilting movement within a predetermined angle range, respectively, as shown in the figure. 8-37, 37 are connected. Then, under the assembled and connected state of both 5, a hydraulic pump is installed in a gear housing space 38 which is provided by penetrating the valve block BB held between the two shafts 3 and 3. The pinion 32 on the PE side and the pinion 32 on the IE side (of the hydraulic motor) are arranged close to each other with their axes parallel to each other and their opposing positions displaced, and one of these pinions 32 is placed between the jII pinions 32 and 32. A pair of idlers 40 and 41 that mesh with the sliding clutch 3
It is provided integrally with 9 and is interposed between the two so as to be freely intermittent. That is, the idler 40.41 is located in the gear housing space 3 located within the valve block BB.
The pinion 32.32 is mounted on a clutch 39 which is slidably disposed in the direction of the pinion actuating shaft 33.33 within the
are arranged in a row at intervals corresponding to the displacement of the clutch.
In the state, one of the idlers 40 meshes with the pinion 32 on the hydraulic pump PE side, and the other idler 41 meshes with the pinion 32 on the IE side (the clutch 39 is the hydraulic motor), and the clutch 39 is in the OFF state. Then, the mesh is broken and the ball is freed. And this clutch 3
9 is made by reciprocating displacement of the clutch operating shaft 4z that comes into contact with one end of the clutch 39. therefore,
In a device equipped with such an operation mechanism, when the clutch is ON and one gear is operated and the 8-37 is tilted, the pinion 3
The gear shift operation is performed by meshing feed from 2, and the tilting plate 10 of the engine on the 8-37 side is tilted in a predetermined direction to increase or decrease the capacity. The tilting plate 10 of the other engine is also tilted in the opposite direction by the same angle at the same time, thereby decreasing or increasing the capacity. In other words, variable displacement control of the pump PE and the motor ME can be performed simultaneously by operating a single speed change lever. Further, when the clutch is OFF, the capacities of the pump PE and the motor ME can be independently and freely variably controlled by each speed change operation and the operation 8-37.

Next, we will explain the operation and effects of the transmission device configured as described above, which consists of a pair of hydraulic pump PM, hydraulic motor, and ε.The operation is basically exactly the same as that of the existing transmission device of this type. That is, from the input shaft I to the hydraulic pump P
When the hydraulic pump PE is driven by transmitting torque to the rotating shaft 4 of E, the hydraulic motor receives high pressure from the outflow port connected to the inflow port of E (hydraulic motor) and the outflow port connected to the inflow port of E. of hydraulic fluid is discharged.

Then, the hydraulic motor E is rotated by this high-pressure hydraulic fluid flowing in, and torque is transmitted to the output shaft H connected to the rotating shaft 4. At this time, the operating lever 37.3
If the amount of B of the hydraulic pump PE and/or the hydraulic motor ME is changed by the tilting operation in step 7, the input torque on the pump PE side is steplessly changed in various ways according to the variable operation, and the motor is controlled. This allows output from the ME side.

The hydraulic transmission 'JM' is characterized by low energy loss and extremely high power transmission efficiency. This is due to the fact that the hydraulic pump PE and the hydraulic motor ME constituting this transmission are both constituted by the above-mentioned static pressure balance type diagonal shaft type pump/motor. The detailed operating principle of this pump/motor will be omitted (if necessary, Japanese Patent Application No. 59-39960 and Japanese Patent Application No. 59-617 filed by the present applicant) will be omitted.
08 and Japanese Patent Application No. 59-64690), this is because the friction between each component that causes energy loss can be minimized as described below. . In other words, in a system in which the hydraulic pressure in the axial direction acting on the cylinder block 9, the piston 15, and the torque plate 7 is statically balanced, the hydraulic pressure ultimately causes the torque plate 7 to have a rotational direction. A force couple is generated, and the force couple balances the human output torque transmitted to the rotating shaft 4. That is, as shown in FIG. 6, the force F of the hydraulic fluid in the connection boat 12, which is the first pressure pocket, presses the cylinder block 9 in the direction of the piston 15.

and the total force F2 of the hydraulic fluid in the piston inner chamber 20 passing through this region pressing the cylinder block 9 in the direction of the valve surface 11 are approximately balanced, and there is a slight balance difference (F 2 F The cylinder block 9 is brought into contact with the valve surface 11 via the liquid film due to the force 223 and the weak biasing force 223. Also, the seventh
As shown in the figure, the force F2' of the hydraulic fluid in the piston inner chamber 20 presses the piston 15 in the direction of the torque plate 7.
and the force F by which the hydraulic fluid in the second pressure pocket 24 presses the piston 15 in the direction of the cylinder block 9.

The piston 15 is in a state of floating in the hydraulic fluid. Roughly speaking, as shown in FIG. 8, the force F of the hydraulic fluid in the piston inner chamber 20 pressing the torque plate 7 in the direction of the pressure receiving surface 8 via the piston 15
The thrust direction component F of the force F3' which substantially balances the thrust direction force F2'CDSθ of 2° and causes the hydraulic fluid in the second pressure pocket 24 to press the torque plate 7.
3' cos O and the force F4 by which the hydraulic fluid in the third pressure pocket 27 presses the torque plate 7 in the direction of the piston 15 are approximately balanced, and F2°CaSσ - F
The torque plate 7 is brought into contact with the pressure-receiving surface 8 by the slight force of , and the weak biasing force of the lever 23 . Then, the radial direction component F7'5i of the force F2'
The sum of nO generates a rotational couple in the torque plate 7, which counteracts the input/output torque of the rotating wheel 4. Therefore, in such a case, a falling moment acts on the piston 15 and the piston 15 rubs against the inner circumferential surface of the cylinder hole 14, or the liquid film is torn and the spherical end of the cylinder block 9 and the piston 15 It is possible to effectively prevent inconveniences such as seizure and abrasion caused by the valve surface 11 and the spherical seat 19 being pressed directly, and mechanical efficiency can be greatly improved. In addition, in this case, the torque plate 7, piston 15, and cylinder block 9 do not need to have a function as a transmission element that transmits mechanical moment, pressing force, etc.
In other words, in an ideal state, these members:
It only serves as a sealing member to form a pressure liquid column of the required size and direction at the required location.

Therefore, the torque plate 7, the piston 15, and the cylinder block 9 are prevented from being subjected to excessive force or being worn out. In other words, between the cylinder block 9 and the tilting plate 1O, which are the sliding parts, and the torque plate 7 and the housing l (pressure-receiving surface 8), these rotating members are supported via a liquid film of hydraulic fluid, so mechanical friction at this sliding portion is very effective. It is reduced to

For the above-mentioned reasons, this hydraulic transmission is capable of exhibiting extremely good power transmission efficiency compared to the existing one constructed with a 7-axis piston pump/motor.

In addition, in this hydraulic two-type transmission, the capacity variable operation of the hydraulic pump PE and/or the hydraulic motor ME can be performed easily and easily, so that the range and pattern of speed change can be varied in various ways. It also has features that make it easy to obtain. That is, in this transmission, both the hydraulic pump PE and the hydraulic motor XE are integrated with #4 of the tilting plate 10 by rotating the pinion 32, and the cylinder block 9 changes the inclination angle, thereby changing the capacity. However,
If such a variable capacity mechanism 30 is provided, it is small in size and has a simple structure, and at the same time, the inclination angle of the cylinder block 9 can be adjusted to the rotation of the pinion 32 caused by the drive from the speed change operation lever 37. It can be controlled instantaneously and precisely to the desired value. and,
Since the capacity of the hydraulic pump PE or the hydraulic motor can be freely adjusted and varied in this manner, this transmission device can be easily provided with various speed change patterns depending on its purpose. 9 to 11 show specific examples of such shift patterns. First, FIG. 9 shows the clutch OF
This figure shows an example of the speed change mode in state F, that is, when both the pinions 32 and 32 are rotated independently by the respective speed change operation levers 37 and 37. ), and the 10th
The figure and FIG. 11 show the situation when the clutch is ON, that is, when both the binions 32 and 32 are engaged through the idler 40 and 41, and when only the pump 8-37 is driven to rotate by changing the speed on the pump side. Similarly, an example of a speed change mode is shown. As can be seen from these examples, if the device is equipped with the above-mentioned operating mechanism, the independent rotational operations of both pinions 32, 32 and the idler 40, 41 performed by one of the speed change operation levers 37 can be performed. By combining the associated rotational operation of both pinions 32, 32, a wide variety of shifting patterns can be created over a wide shifting range.

Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments, and can be implemented in various other forms. FIG. 12 shows one of such modified embodiments, and the reference numerals given to the main parts thereof are the same as in the example. In this embodiment, the hydraulic pump PE and the hydraulic motor IIIE are directly connected to their rear covers 3, 3 without sandwiching the valve block, and the pinions 32 and 32 are respectively shifted to different speeds without using the idler. It is designed so that it can be rotated independently and freely by operating the 8-37, 37. In this case, both the hydraulic pump PE and the hydraulic motor E on both sides are connected to the connection port 1).
The valve surface 11 having a diameter of 2.13 is provided not on the side of the front pressure plate 10, but on the front force-2 inner surface of the housing 1, specifically on the pressure receiving surface 8. In this case as well, the pressure pockets 12. are located at required locations to balance the static pressure of each piston 15, cylinder block 9, and torque plate 7 in the axial direction.
24.27 (however, in this construction the form of the pressure pocket 12 and the pressure pocket 27 is reversed to that of the previous example), and furthermore, in this case the connection of the valve face 11 is Port 12.13 and hydraulic pump PK
and each front cover 2 of the hydraulic motor ME, and their inflow and outflow ports (not shown) that are open on the outer surface of the housing l on the z side are connected and communicated with each other through liquid communication pipes 43 and 44 to ensure necessary circulation of the working fluid. It constitutes a circuit. Even in a transmission having such a configuration, the operation and effect are basically the same as those of the previous example.

To give another embodiment of the present invention, in the embodiment, both the hydraulic pump PE and the pump/motor constituting the motor TIE are variable displacement types equipped with a variable displacement mechanism, but only one of them is of the above-mentioned type. It is also possible to configure one of the variable capacity type with the variable capacity mechanism 30 and the other of the constant capacity type.

Further, in the above embodiment, the pair of hydraulic pump PE and hydraulic motor ME are arranged in series, but the arrangement can be parallel, intersecting, or other arbitrary arrangement, and they can be placed at separate positions. It is also possible to install it separately.

Note that when configuring the hydraulic transmission of the present invention, it is possible not only to configure a hydraulic pump PE and a hydraulic motor ME in a one-to-one pair, but also to configure a plurality of motors ME for one pump PM, for example. may be combined in pairs.

[Effects of the Invention] As described above, the present invention provides a new type of oblique shaft type piston pump/motor whose main component is a static pressure parallel plate and which is equipped with a variable displacement mechanism having excellent variable performance. Since the hydraulic pump and hydraulic motor have extremely low energy loss due to mechanical friction, it is possible to obtain particularly high power transmission efficiency and to meet the diverse demands of speed change patterns. Therefore, it was possible to provide a hydraulic transmission device that can perform the following functions.

[Brief explanation of drawings]

@ Figure 1 is an overall cross-sectional view showing one embodiment of the end 11. Figure 2 is an enlarged cross-sectional view of a part thereof. Figure 3 is a cross-sectional view of the ■-■ line in Figure 1 with part number IV-1' partially omitted.
The cross-sectional view taken along the V line and FIG. 5 are partial cross-sectional views taken along the same <V-V line. FIG. 6, FIG. 7, and FIG. 8 are all action explanatory diagrams showing the pressure balance state. FIG. 9, FIG. 1O, and FIG. 11 are all diagrams showing specific examples of speed change modes by the transmission device of the embodiment. Figure 812 is a sectional view showing another embodiment of the present invention. Engineering...Manual shaft, ■...Output shaft PE...Hydraulic pressure pump, ME11IIe hydraulic motor BB
IIe11 Valve block H, L - working/hydraulic circuit l...Housing 2-Y front cover, 3...rear cover 4...
Rotating shaft, 7＠-,) Luk plate 9--・Cylinder block, 10...Tilting plate 11--・Valve surface 12.13...Fist connection port (pressure pocket) 14・a
- Cylinder hole, 15@-- Piston 18...Piston outer end (slope end) 19... Spherical catch, 20-- Own piston inner chamber 24, fist, pressure pocket 27... Pressure pocket 30-Conflict/capacity a (receiving mechanism 31/oll tooth profile, 32--pinion 33, .. operating shaft, 37-@-operating lever 38... gear accommodation space,
39 Middle...Clutch 40.41---Idler, 42-...Clutch 9ch operating shaft 42 43.44・◆・Liquid pipe L...Inclination axis center, M...Rotation center 0... Tilt center

Claims (1)

[Claims] A hydraulic pump and a hydraulic motor are provided as a pair, an outflow port of the pump is connected to an inflow port of the motor, and an inflow port of the pump is connected to an outflow port of the motor; A transmission device that varies the capacity of a pump and/or the motor to steplessly change the speed of the rotational input of the pump and output the rotation from the motor, In a housing with a port, there is a rotating shaft for input/output supported by the housing, a torque plate that is rotatably provided on the rotating shaft, and a rotary shaft that rotates around an inclined axis that intersects with the center of rotation of the torque plate. a cylinder block that is rotatably provided and has a plurality of cylinder holes parallel to the tilted axis and opened toward the torque plate; and a cylinder block that is slidably fitted into each cylinder hole of the cylinder block and opposite to the cylinder block. a plurality of pistons whose outer ends are pivotally supported on the torque plate; and a valve surface having a connection port for connecting an inflow/outflow port of the housing to each of the cylinder holes; and between each of the outer ends of the pistons and the torque plate, between the cylinder block and a housing or tilting plate that slides on the cylinder block, and between the torque plate and the housing that slides on the torque plate. A diagonal shaft type piston pump/motor is provided with a pressure pocket for introducing liquid so that the piston, cylinder block, and torque plate can be statically balanced in the axial direction, and the hydraulic pump and the hydraulic motor are The tilting plate is disposed on at least one of the oblique shaft type piston pump/motor and is arranged so as to be tiltable with respect to the torque plate, and on which the cylinder block is slidably engaged with the cylinder block so as to be relatively rotatable and integrally tiltable. and a pinion that is disposed on the rear side of the tilting plate opposite to the cylinder block and meshes with a tooth profile carved along an arcuate surface formed on the rear surface of the tilting plate, and an operation that rotates this pinion. 1. A hydraulic transmission characterized by being provided with a variable capacity mechanism comprising a shaft.