JP2005083498A - Hydraulic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a configuration capable of reducing driving force for turning a swash plate and allowing deviation of center of turn of the swash plate from center of turn of a link arm when adopting a mechanism turning the swash plate through the link arm to increase degree of freedom in arrangement of a configuration for turning the swash plate. <P>SOLUTION: A second arm engaging member 62 is rotatably fitted into a second engaging pin 66 provided on an input side swash plate 6, and the second arm engaging member 62 is slidably fitted into an engaging channel 63b provided at one end of the link arm 63. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a technology of a hydraulic device or a power transmission device that can be widely used in various industrial fields such as industrial machines and vehicles.

Conventionally, the first and second rotary shafts, the first and second plungers that reciprocate in the axial direction, and the first spool valve and the second spool that also reciprocate in the axial direction. A valve, a cylinder block that accommodates the first plunger, the second plunger, the first spool valve, and the second spool valve and rotates integrally with the first rotation shaft, and an inclination angle with respect to the axis is changed. A first swash plate that contacts the first plunger on a possible swash plate surface, and a second rotating shaft that is in contact with the second plunger on a swash plate surface that forms a predetermined inclination angle with respect to the axis. A hydraulic circuit that communicates the hole that accommodates the first plunger and the hole that accommodates the second plunger is formed in the cylinder block, and the first spool valve The first plunger 2. Description of the Related Art A hydraulic device technology that switches a flow path of hydraulic oil that enters and exits a plunger hole that accommodates the hydraulic oil and switches a flow path of hydraulic oil that enters and exits a plunger hole that houses a second plunger by a second spool valve is known. . For example, as described in Patent Document 1.
Also, a hydraulic device (hydrostatic continuously variable transmission (HST), hydraulic-mechanical continuously variable transmission) that rotates a swash plate inclined with respect to the axis of the cylinder block via a link arm that is rotatably provided. The technology of the device (HMT), other transmissions, power transmission devices, and the like is also known.

JP 2003-14079 A

In the hydraulic apparatus as described above, if the swash plate is configured to rotate by directly driving the swash plate mounting pins, the distance from the center of rotation of the swash plate cannot be increased due to restrictions on the placement of the mounting pins. Therefore, the driving force for rotating the swash plate must be increased. In addition, it is necessary to provide a drive device for the mounting pin adjacent to the swash plate, and the arrangement of the device is also restricted. Here, if the swash plate is configured to rotate via the link arm, the rotational force of the swash plate can be reduced by the principle of the lever, and the device for driving one arm of the link arm is a swash plate. Therefore, the degree of freedom of arrangement of the device is increased.
However, if the swash plate is rotated via the link arm, an excessive load is applied to the swash plate holding surface or the like if the rotation center of the swash plate and the rotation center of the link arm do not coincide. Problems such as adding will occur. For this reason, strict assembly accuracy is required in which the center of rotation of the swash plate and the center of rotation of the link arm are matched.
An object of the present invention is to reduce the driving force for rotating the swash plate and to rotate the swash plate via the link arm in order to increase the degree of freedom in arranging the structure for rotating the swash plate. An object of the present invention is to provide a configuration that allows a deviation between the rotation center of a swash plate and the rotation center of a link arm when a moving mechanism is employed.

  The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

That is, according to the first aspect of the present invention, in the hydraulic apparatus, the angle formed between the swash plate surface of the swash plate and the axis of the cylinder block can be changed by rotating the swash plate via a link arm that is rotatably provided. ,
A protruding member provided on the swash plate is fitted on the engaging member, and the engaging member is slidably fitted in an engaging groove provided on one end of the link arm.

  As effects of the present invention, the following effects can be obtained.

In claim 1, the driving force for rotating the swash plate can be reduced, and the link arm can be rotated without causing the link arm or the swash plate to malfunction or to be damaged or worn. It is possible to change the angle (inclination angle) formed between the swash plate surface of the swash plate and the axis of the cylinder block by rotating the swash plate.
Further, even if the imaginary rotation center of the swash plate and the axis center of the rotation axis of the link arm are not completely matched at the time of assembly work, malfunction does not occur, and workability at the time of assembly is improved.
Furthermore, it is possible to increase the degree of freedom in arranging the configuration for rotating the swash plate.

Next, embodiments of the invention will be described.
1 is a side sectional view according to the first embodiment of the hydraulic apparatus, FIG. 2 is a side sectional view of the cylinder block according to the first embodiment of the hydraulic apparatus, FIG. 3 is a front view of the cylinder block, and FIG. FIG. 5 is a perspective view of a spool valve guide according to a first embodiment of the hydraulic apparatus, FIG. 6 is a perspective view of a holding member according to the first embodiment of the hydraulic apparatus, and FIG. 7 is a perspective view of an output side swash plate. FIG. 8 is a side view of a main part according to the first embodiment of the hydraulic device, FIG. 9 is a schematic diagram showing a flow of hydraulic oil in the hydraulic closed circuit during speed increasing operation, and FIG. 10 is a hydraulic closed circuit during deceleration operation. FIG. 11 is a developed schematic view of a cylinder block, FIG. 12 is a schematic diagram showing a hydraulic closed circuit of the hydraulic device of the present invention, and FIG. 13 is an input side hydraulic pressure in the hydraulic device of the present invention. FIG. 14 is a diagram showing the relationship between the stroke volume of the device and the rotational speed of the output shaft. 15 is a partial cross-sectional view of the link arm, FIG. 16 is a schematic plan view showing the link arm mechanism, and FIG. 17 is a diagram showing the positional relationship between the link arm and the input side swash plate before rotation. 18 is a view showing the positional relationship between the link arm after rotation and the input side swash plate, FIG. 19 is a side sectional view according to the second embodiment of the hydraulic device, and FIG. 20 is a second embodiment of the hydraulic device. 21 is a side sectional view of the cylinder block, FIG. 21 is a perspective view of a spool valve guide according to a second embodiment of the hydraulic device, and FIG. 22 is a side view of a main part according to the second embodiment of the hydraulic device.

  Hereinafter, the detailed configuration of the hydraulic continuously variable transmission 1 which is the first embodiment of the hydraulic apparatus of the present invention will be described with reference to FIGS. 1 to 8. The hydraulic continuously variable transmission 1 according to the present embodiment is used for shifting the driving force of a working vehicle (such as a tractor), but is not limited thereto, and various industries such as industrial machines and vehicles. Widely available in the field.

The hydraulic continuously variable transmission 1 mainly includes an input shaft 2, an input side housing cover 3, an input side bearing housing 4, a swash plate holding member 5, an input side swash plate 6, a cylinder block 7, and input side plungers 8 and 8. ..., input side spool valves 9, 9 ..., output side plungers 10, 10 ..., output side spool valves 11, 11 ..., output side swash plate 12, output shaft 13, output side bearing housing 14 , Etc.
In the following description, the direction of arrow A in FIG. 1 (the direction in which the tip 2a protrudes in the axial direction of the input shaft 2) is defined as “front”.

Hereinafter, the input shaft 2 which is the first rotating shaft in the present embodiment will be described in detail with reference to FIG.
The input shaft 2 is a shaft for transmitting a driving force from a driving source such as an engine to the hydraulic continuously variable transmission 1. The input shaft 2 is rotatably supported by the input side bearing housing 4 via an input side conical roller bearing 21 and an input side needle roller bearing 22. The inner ring of the input side conical roller bearing 21 is made relatively to the input shaft 2 by a stepped portion provided on the input shaft 2 and an input side bearing tightening nut 23 screwed from the distal end portion 2a side of the input shaft 2. Fixed non-rotatable. Further, the cylinder block 7 is fixed to the input shaft 2 so as not to be relatively rotatable by spline fitting.

Hereinafter, the input side bearing housing 4 that is a bearing member that pivotally supports the first rotating shaft in the present embodiment will be described in detail with reference to FIG.
The flange portion 4a that forms the front portion of the input side bearing housing 4 is formed in a substantially disc shape, and a bolt hole for fixing the hydraulic continuously variable transmission 1 to a transmission case or the like is formed in the peripheral portion thereof. Yes. In the case of the present embodiment, the flange portion 4a is fixed to the transmission housing case 24 for housing the transmission of the work vehicle by bolt fastening. In addition, an O-ring is interposed at a contact portion between the input side bearing housing 4 and the transmission housing case 24.
As described above, the hydraulic oil is prevented from leaking from the contact portion between the input side bearing housing 4 and the transmission housing case 24 to the outside of the transmission housing case 24, and foreign matters such as dust are transmitted to the transmission housing case 24. And intrusion into the hydraulic continuously variable transmission 1 is prevented.
On the other hand, the body portion 4b forming the rear portion of the input side bearing housing 4 is formed in a substantially cylindrical shape, and a through hole for allowing the input shaft 2 to pass therethrough is formed. The outer ring of the input side conical roller bearing 21 is fitted to the front part of the inner peripheral surface of the through hole, and the input side needle roller bearing 22 is fitted to the rear part of the inner peripheral surface.

Hereinafter, the input side housing cover 3 will be described in detail with reference to FIG.
The input-side housing lid 3 is a substantially disk-shaped member having a through hole for allowing the input shaft 2 to pass through substantially at the center, and oil is provided between the input-side housing lid 3 and the input shaft 2 in the through-hole. A seal 25 is interposed. A retaining ring 26 is provided at the front end of the through hole of the input side housing lid 3 to prevent the oil seal 25 from falling off the input side housing lid 3.
The input-side housing lid 3 is fixed to the front end portion of the input-side bearing housing 4 by fastening bolts, and an O-ring is interposed at a contact portion between the input-side housing lid 3 and the input-side bearing housing 4.
As described above, the hydraulic fluid leaks out of the transmission housing case 24 from the clearance between the through hole of the input side housing lid 3 and the input shaft 2 and the contact portion between the input side housing lid 3 and the input side bearing housing 4. And preventing foreign matter such as dust from entering the transmission housing case 24 and the hydraulic continuously variable transmission 1.

Hereinafter, the swash plate holding member 5 will be described in detail with reference to FIG.
The swash plate holding member 5 supports the input side swash plate 6 so that the inclination angle of the swash plate surface 6a of the input side swash plate 6 (the angle formed by the swash plate surface 6a and the axis of the input shaft 2) can be changed. And a substantially disc-shaped mounting portion 5a having a hole formed in a substantially central portion, a holding portion 5b protruding rearward from the mounting portion 5a, and the like.
The mounting portion 5a is fitted to the body portion 4b of the input side bearing housing 4, and is fixed to the flange portion 4a of the input side bearing housing 4 by bolt fastening.
The holding portions 5b and 5b protrude rearward from the mounting portion 5a, and the rear end portions of the holding portions 5b and 5b have a shape recessed in a substantially semicircular shape. A metal bearing 27 for a swash plate is fixed by a spring pin 28 in the semi-circular recess.

Hereinafter, the input side swash plate 6 which is the first swash plate in this embodiment will be described in detail with reference to FIGS. 1 and 2.
The input-side swash plate 6 converts the rotational driving force of the input shaft 2 into a force that reciprocates the input-side plunger 8 (that is, the hydraulic oil pressure in the hydraulic circuit formed in the cylinder block 7). By changing the inclination angle of the plate surface 6a, the stroke when the input-side plunger 8 is reciprocated (that is, the amount of hydraulic oil pressure-fed by the input-side plunger 8 when reciprocating) is changed. The input-side swash plate 6 is a member having a hole through which the input shaft 2 penetrates substantially in the center, and a swash plate surface 6a, which is a plate surface, is formed on one of the members.
The protruding end (contact plate 8c) of the input side plunger 8 contacts the swash plate surface 6a. On the other hand, holding portions 6b and 6b are projected from the other plate surface. The shapes of the holding portions 6b and 6b correspond to the semicircular recessed portions of the holding portions 5b and 5b of the swash plate holding member 5, and the input side swash plate 6 is swash plate at the holding portions 6b and 6b. The holding member 5 can be rotated while being in contact with the holding portions 5b and 5b (more precisely, a swash plate metal bearing 27 provided in a semicircular recess in a side view). It is possible to change the inclination angle of the surface 6a (the angle formed by the swash plate surface 6a and the axis of the input shaft 2).
It should be noted that the diameter of the hole formed in the approximate center of the input side swash plate 6 is such that the input shaft 2 does not interfere even if the input side swash plate 6 rotates.

Hereinafter, the cylinder block 7 which is an embodiment of the cylinder block in the hydraulic apparatus of the present invention will be described in detail with reference to FIGS. 1, 2, and 3.
The cylinder block 7 is a substantially columnar member, and a through hole 7c that penetrates the input shaft 2 from the input side end surface 7a to the output side end surface 7b is formed in a substantially central portion of the cylinder block 7, and the through hole 7c Spline processing is applied to the rear end portion (end portion on the output side end surface 7b side) of the inner peripheral surface. On the other hand, when the input shaft 2 is penetrated through the cylinder block 7, the outer peripheral surface of the input shaft 2 corresponding to the splined portion of the cylinder block 7 is also splined. 2 and splined together so that they cannot rotate relative to each other and rotate together.
The input side end surface 7 a is a surface facing the input side swash plate 6, and the output side end surface 7 b is a surface facing the output side swash plate 12. Both the input side end surface 7 a and the output side end surface 7 b are orthogonal to the axis of the input shaft 2.

In the cylinder block 7, a total of seven input-side plunger holes 31, 31... And a total of seven input-side spool valve holes 32, 32... Are input from the input-side end face 7a of the cylinder block 7. It is drilled toward the axial direction of the shaft 2.
The input side plunger holes 31, 31, etc. are holes formed in the cylinder block 7 to accommodate the input side plungers 8, 8, etc., and the longitudinal direction thereof is parallel to the axis of the input shaft 2. . Further, the input side plunger holes 31, 31... Do not penetrate to the output side end surface 7b, and are drilled to a position slightly closer to the output side end surface 7b than the intermediate position between the input side end surface 7a and the output side end surface 7b. I'm leaning.
The input side spool valve holes 32, 32... Are holes formed in the cylinder block 7 to accommodate the input side spool valves 9, 9, and the longitudinal direction thereof is parallel to the axis of the input shaft 2. It is. Further, the input side spool valve holes 32, 32... Penetrate to the output side end face 7b.

As shown in FIG. 3, the input-side plunger holes 31, 31... Are equidistant (on a concentric circle) and adjacent to the through-hole 7 c through which the input shaft 2 is inserted as viewed from the axial direction of the input shaft 2. It arrange | positions so that the distance between input side plunger holes 31 and 31 may become equal distance.
The input-side spool valve holes 32, 32... Are also equidistant (on concentric circles) and adjacent to the input-side spool as viewed from the axial direction of the input shaft 2 through the through-hole 7c through which the input shaft 2 is inserted. It arrange | positions so that the distance between valve holes 32 and 32 may become equal distance. At this time, the input-side spool valve holes 32, 32,... Are closer to the through-hole 7c than the input-side plunger holes 31, 31, and the center of the through-hole 7c in the radial direction of the cylinder block 7. The center of the input side spool valve hole 32 is arranged on a straight line connecting the centers of the input side plunger hole 31.

From the outer peripheral surface of the cylinder block 7, communication holes 33 that communicate with the set of the input side plunger hole 31 and the input side spool valve hole 32 are respectively formed (seven locations in total).
At this time, the communication holes 33, 33,... Are drilled at positions substantially in the center of the cylinder block 7 in the axial direction of the input shaft 2, and the communication holes 33, 33,. The end is closed by seal plugs 34, 34.
In addition, the inner diameter of the merging portion 36 that is the merging portion of the communication holes 33, 33... And the input side plunger holes 31, 31, is formed larger than the inner diameter of the input side spool valve hole 32. ing. With this configuration, when the input-side plunger hole 31, the input-side oil chamber 35, and the output-side oil chamber 45 are blocked by the enlarged diameter portion 9a of the input-side spool valve 9 (neutral position), the expansion is performed. Since the oil pressure is uniformly applied to the outer periphery of the diameter portion 9 a, it is possible to prevent the input side spool valve 9 from being pressed in a specific circumferential direction inside the input side spool valve hole 32.
Further, the dimensional accuracy in the axial direction of the merging portion 36 affects the accuracy of the timing at which the flow path of the hydraulic circuit is switched by the reciprocating movement of the input side spool valve 9, but in the present embodiment, the input side spool When the valve holes 32, 32... Are drilled, the merging portion 36 is centered so that the merging portion 36 can be formed with high dimensional accuracy.

The cylinder block 7 has a total of seven output side plunger holes 41, 41... And a total of seven output side spool valve holes 42, 42... From the output side end face 7 b of the cylinder block 7 to the input shaft 2. It is drilled toward the axial direction.
The output side plunger holes 41... Are holes formed in the cylinder block 7 to accommodate the output side plungers 10, 10... And the longitudinal direction thereof is parallel to the axis of the input shaft 2. . Further, the output side plunger holes 41, 41... Do not penetrate to the input side end surface 7a, and are drilled to a position slightly closer to the input side end surface 7a than the intermediate position between the input side end surface 7a and the output side end surface 7b. I'm leaning.
The output side spool valve holes 42, 42... Are holes formed in the cylinder block 7 to accommodate the output side spool valves 11, 11, and the longitudinal direction thereof is parallel to the axis of the input shaft 2. It is. Further, the output side spool valve holes 42, 42... Penetrate to the input side end face 7a.

As shown in FIG. 3, the output side plunger holes 41, 41... Are equidistant (on concentric circles) and adjacent to the through hole 7 c through which the input shaft 2 is inserted, when viewed from the axial direction of the input shaft 2. It arrange | positions so that the distance between the output side plunger holes 41 and 41 may become equal distance.
The output-side spool valve holes 42, 42... Are also equidistant (on concentric circles) and adjacent to the through-hole 7c through which the input shaft 2 is inserted, as viewed from the axial direction of the input shaft 2. It arrange | positions so that the distance between valve holes 42 and 42 may become equal distance. At this time, the output-side spool valve holes 42, 42,... Are closer to the through-hole 7c than the output-side plunger holes 41, 41, and the center of the through-hole 7c in the radial direction of the cylinder block 7. The center of the output side spool valve hole 42 is arranged on a straight line connecting the centers of the output side plunger holes 41.

Communication holes 43 that communicate with a set of output-side plunger holes 41 and output-side spool valve holes 42 from the outer peripheral surface of the cylinder block 7 are respectively formed (a total of seven locations).
At this time, the communication holes 43, 43... Are drilled at a position that is substantially the center of the cylinder block 7 in the axial direction of the input shaft 2, and the communication holes 43, 43. The end is closed by seal plugs 44, 44.
Further, the inner diameter of the merging portion 46 that is the merging portion of the communication holes 43 · 43 ··· and the output side plunger holes 41 · 41 ··· is formed larger than the inner diameter of the output side spool valve hole 42. ing. With this configuration, when the output-side plunger hole 41, the input-side oil chamber 35, and the output-side oil chamber 45 are blocked by the enlarged diameter portion 11a of the output-side spool valve 11 (neutral position), the expansion is performed. Since the oil pressure is uniformly applied to the outer periphery of the diameter portion 11 a, it is possible to prevent the output side spool valve 11 from being pressed in a specific circumferential direction inside the output side spool valve hole 42.
Further, the dimensional accuracy in the axial direction of the merging portion 46 affects the accuracy of the timing at which the flow path of the hydraulic circuit is switched by the reciprocating motion of the output side spool valve 11, but in this embodiment, the output side spool When the valve holes 42, 42... Are drilled, the merging portion 46 is centered so that the merging portion 46 can be formed with high dimensional accuracy.

As shown in FIG. 3, the input side plunger holes 31, 31... And the output side plunger holes 41, 41... Are alternately adjacent when viewed from the axial direction of the input shaft 2 (that is, through holes). 7) are arranged in the order of input side plunger hole 31 → output side plunger hole 41 → input side plunger hole 31 → output side plunger hole 41 →.
In addition, the output side spool valve holes 32, 32... And the output side spool valve holes 42, 42,... Are alternately adjacent to each other when viewed from the axial direction of the input shaft 2 (that is, through holes 7c). Are arranged in the order of input side spool valve hole 32 → output side spool valve hole 42 → input side spool valve hole 32 → output side spool valve hole 42 →.

As shown in FIG. 2, a total of two inner peripheral grooves including a first inner peripheral groove and a second inner peripheral groove are formed on the inner peripheral surface of the through hole 7 c of the cylinder block 7. The inner circumferential groove is formed in a ring shape in the circumferential direction of the inner circumferential surface, and any of the inner circumferential grooves has an input side spool valve hole 32, 32... And an output side spool valve hole 42, 42. Communicate.
In the following description, the space surrounded by the first inner circumferential groove close to the input side end face 7a and the outer peripheral face of the input shaft 2 is referred to as the input side oil chamber 35, and the second inner side close to the output side end face 7b. A space surrounded by the circumferential groove and the outer peripheral surface of the input shaft 2 is defined as an output side oil chamber 45.

  In this embodiment, the number of the input side plunger 8, the input side spool valve 9, the output side plunger 10, and the output side spool valve 11 accommodated in the cylinder block 7 is seven, but is not limited thereto. If there are a plurality, the same effect can be obtained.

In the following, with reference to FIG. 1 and FIG. 2, an input side plunger 8 which is an embodiment of the first plunger in the hydraulic device of the present invention and an embodiment of the second plunger in the hydraulic device of the present invention. A certain output side plunger 10 will be described in detail.
In this embodiment, the input-side plunger 8 and the output-side plunger 10 have the same shape so as to share parts. However, the present invention is not limited to this, and the input-side plunger 8 and the output-side plunger 10 may have different shapes. good.

The input side plunger 8 converts the rotational driving force of the input shaft 2 into the hydraulic oil pressure in the hydraulic circuit formed in the cylinder block 7. The output-side plunger 10 converts the pressure of the hydraulic oil in the hydraulic circuit formed in the cylinder block 7 into the rotational driving force of the output shaft 13.
.. Are accommodated in the input side plunger holes 31, 31..., And the output side plungers 10, 10.

As shown in FIG. 2, the input-side plunger 8 is mainly composed of a plunger portion 8a, a ball 8b, a contact board 8c, and the like.
The plunger portion 8 a is a substantially cylindrical member and can reciprocate while being in sliding contact with the input side plunger hole 31 of the cylinder block 7. The ball 8b is a substantially spherical member, and a contact disk 8c, which is a substantially disk-shaped member, is fixed. The abutment plate 8c is swingably connected to the protruding end of the plunger portion 8a (the end portion protruding from the input side end surface 7a toward the input side swash plate 6) by the ball 8b, and the plunger portion 8a. The protruding end is closed by the ball 8b (more precisely, the ball 8b and the contact plate 8c are provided with lubricating oil passages, and the hydraulic oil in the input side plunger hole 31 is little by little. It leaks from the oil passage to the contact surface between the contact plate 8c and the input side swash plate 6 and lubricates the contact surface).

  A spring retainer 29 and a spring 30 are accommodated in the plunger portion 8a. One end of the spring 30 abuts against the spring retainer 29, and the other end projects from the open end of the plunger portion 8 a and abuts against the wall surface of the input side plunger hole 31. Accordingly, the input side plunger 8 is biased by the spring 30 in a direction protruding from the input side end surface 7a of the cylinder block 7 (that is, a direction in which the contact plate 8c contacts the swash plate surface 6a of the input side swash plate 6). ing.

As shown in FIG. 2, the output side plunger 10 is mainly composed of a plunger portion 10a, a ball 10b, a contact board 10c and the like.
The plunger portion 10 a is a substantially cylindrical member and can reciprocate while being in sliding contact with the output side plunger hole 41 of the cylinder block 7. The ball 10b is a substantially spherical member, and a contact disk 10c, which is a substantially disk-shaped member, is fixedly provided. The contact plate 10c is swingably connected to the protruding end of the plunger portion 10a (the end portion protruding from the output side end surface 7b toward the output side swash plate 12) by the ball 10b, and the plunger portion 10a. The projecting end is closed by the ball 10b (more precisely, the ball 10b and the contact plate 10c are provided with lubricating oil passages, and the hydraulic oil in the output side plunger hole 41 is little by little. It leaks from the oil passage to the contact surface between the contact plate 10c and the output side swash plate 12, and lubricates the contact surface).

  A spring retainer 29 and a spring 30 are accommodated in the plunger portion 10a. One end of the spring 30 abuts against the spring retainer 29 and the other end projects from the open end of the plunger portion 10 a and abuts against the wall surface of the output side plunger hole 41. Accordingly, the output side plunger 10 is biased by the spring 30 in a direction protruding from the output side end surface 7b of the cylinder block 7 (that is, a direction in which the contact plate 10c contacts the swash plate surface 12a of the output side swash plate 12). ing.

Hereinafter, the input side spool valve 9 which is an embodiment of the first spool valve in the hydraulic apparatus of the present invention and the implementation of the second spool valve in the hydraulic apparatus of the present invention will be described with reference to FIGS. The output side spool valve 11 which is one form will be described in detail.
In this embodiment, the input-side spool valve 9 and the output-side spool valve 11 have the same shape for sharing parts, but the present invention is not limited to this, and the input-side spool valve 9 and the output-side spool valve 11 May have different shapes.

The input side spool valve 9 switches the flow path of the hydraulic oil that enters and exits the input side plunger hole 31 that houses the input side plunger 8. The input-side spool valve 9 has a substantially cylindrical member having a different outer diameter, and is mainly composed of an enlarged diameter portion 9a, enlarged diameter portions 9b and 9b, valve shaft portions 9c and 9c, an engaging portion 9d, and the like.
The enlarged diameter portion 9a and the enlarged diameter portions 9b and 9b are substantially cylindrical portions, and the outer diameter thereof is substantially the same as the inner diameter of the input side spool valve hole 32 formed in the cylinder block 7. Therefore, the enlarged diameter portion 9a and the enlarged diameter portions 9b and 9b can reciprocate while being in airtight sliding contact with the input side spool valve hole 32.
The enlarged diameter portion 9a is disposed at an intermediate portion (or a substantially central portion) in the longitudinal direction (reciprocating direction) of the input side spool valve 9. The enlarged diameter portions 9 b and 9 b are located at both ends in the longitudinal direction of the input side spool valve 9.
The valve shaft portion 9c is a substantially cylindrical portion having an outer diameter smaller than that of the enlarged diameter portion 9a and the enlarged diameter portions 9b and 9b, and is located between the enlarged diameter portion 9a and the enlarged diameter portions 9b and 9b.
The engaging portion 9d is provided so as to protrude from the one enlarged diameter portion 9b toward the longitudinal direction of the input side spool valve 9. The connecting portion between the engaging portion 9d and the enlarged diameter portion 9b has a constricted shape and engages with the input side spool valve guide 37.

The input-side spool valve 9 is slidably fitted in the input-side spool valve hole 32 so that the engaging portion 9d is in a direction protruding from the input-side end surface 7a of the cylinder block 7.
The enlarged-diameter portion 9b connected to the engaging portion 9d is connected to the input-side oil chamber 35 that is always formed by the first inner circumferential groove even when the input-side spool valve 9 reciprocates in the input-side spool valve hole 32. It is located on the input side end face 7a side with respect to the communication portion in which the side spool valve hole 32 communicates. Further, the enlarged diameter portion 9b farther from the engaging portion 9d allows the output side oil that is always formed by the second inner circumferential groove even when the input side spool valve 9 reciprocates in the input side spool valve hole 32. The chamber 45 and the input side spool valve hole 32 are positioned on the output side end face 7b side with respect to the communication portion that communicates.

Further, the enlarged diameter portion 9 a is located at a position corresponding to the connecting oil passage (communication hole 33) that communicates the input side plunger hole 31 and the input side spool valve hole 32 and the joining portion 36 between the input side spool valve hole 32. Be placed. At this time, the inner diameter of the merging portion 36 is configured to be larger than the outer diameter of the enlarged diameter portion 9a, and the length of the merging portion 36 in the longitudinal direction (reciprocating direction) of the input side spool valve 9 is The length of the enlarged diameter portion 9a is substantially the same.
Therefore, the diameter-enlarged portion 9a is configured such that (1) the input-side oil chamber 35 and the input-side plunger hole 31 are blocked by the input-side spool valve 9 sliding in the input-side spool valve hole 32, and the output-side oil A position where the chamber 45 and the input side plunger hole 31 communicate with each other; (2) a position where all of the input side oil chamber 35, the output side oil chamber 45 and the input side plunger hole 31 are blocked; and (3) an input. It is possible to take a total of three positions: a position where the side oil chamber 35 and the input side plunger hole 31 communicate with each other and the output side oil chamber 45 and the input side plunger hole 31 are blocked.

  Since the relationship between the length of the merging portion 36 and the length of the enlarged diameter portion 9a in the longitudinal direction of the input-side spool valve 9 is appropriately selected according to the drive characteristics of the hydraulic device of the present invention, this embodiment As described above, the present invention is not limited to the case where the length of the merging portion 36 and the length of the enlarged diameter portion 9a in the longitudinal direction of the input side spool valve 9 are configured to be substantially the same. That is, in the longitudinal direction of the input-side spool valve 9, the merging portion 36 may be longer or shorter than the diameter-expanded portion 9a.

The output-side spool valve 11 switches the flow path of the hydraulic oil that enters and exits the output-side plunger hole 41 that houses the output-side plunger 10. The output side spool valve 11 has a substantially cylindrical member having a different outer diameter, and is mainly composed of an enlarged diameter portion 11a, enlarged diameter portions 11b and 11b, a valve shaft portion 11c and 11c, an engaging portion 11d, and the like.
The enlarged diameter portion 11 a and the enlarged diameter portions 11 b and 11 b are substantially cylindrical portions, and the outer diameter thereof is substantially the same as the inner diameter of the output-side spool valve hole 42 formed in the cylinder block 7. Therefore, the enlarged diameter portion 11a and the enlarged diameter portions 11b and 11b can reciprocate while being in airtight sliding contact with the output side spool valve hole 42.
The enlarged diameter portion 11a is disposed at an intermediate portion (or a substantially central portion) in the longitudinal direction (reciprocating direction) of the output side spool valve 11. The enlarged diameter portions 11 b and 11 b are located at both ends in the longitudinal direction of the output side spool valve 11.
The valve stem portion 11c is a substantially cylindrical portion having an outer diameter smaller than that of the enlarged diameter portion 11a and the enlarged diameter portions 11b and 11b, and is located between the enlarged diameter portion 11a and the enlarged diameter portions 11b and 11b.
The engaging portion 11 d is provided so as to protrude from the one enlarged diameter portion 11 b toward the longitudinal direction of the output-side spool valve 11. The connecting portion between the engaging portion 11d and the enlarged diameter portion 9b has a constricted shape and engages with the output-side spool valve guide 47.

The output-side spool valve 11 is slidably fitted in the output-side spool valve hole 42 so that the engaging portion 11d is in a direction protruding from the output-side end surface 7b of the cylinder block 7.
The enlarged-diameter portion 11b connected to the engaging portion 11d has an output-side oil chamber 45 and an output that are always formed by the second inner circumferential groove even when the output-side spool valve 11 reciprocates in the output-side spool valve hole 42. It is located on the output side end face 7b side with respect to the connecting portion that communicates with the side spool valve hole 42. Further, the enlarged diameter portion 11b far from the engaging portion 11d is an input side oil that is always formed by the first inner circumferential groove even when the output side spool valve 11 reciprocates in the output side spool valve hole 42. The chamber 35 and the output side spool valve hole 42 are located on the input side end face 7a side with respect to the communication portion.

Further, the enlarged diameter portion 11 a is located at a position corresponding to a connecting oil passage (communication hole 43) that communicates the output-side plunger hole 41 and the output-side spool valve hole 42 and a merging portion 46 between the output-side spool valve hole 42. Be placed. At this time, the inner diameter of the merging portion 46 is configured to be larger than the outer diameter of the enlarged diameter portion 11a, and the length of the merging portion 46 in the longitudinal direction (reciprocating direction) of the output side spool valve 11 The length of the enlarged diameter portion 11a is substantially the same.
Accordingly, the diameter-enlarged portion 11 a is configured such that (1) the input-side oil chamber 35 and the output-side plunger hole 41 are blocked by the output-side spool valve 11 sliding in the output-side spool valve hole 42, and the output-side oil A position where the chamber 45 communicates with the output side plunger hole 41, (2) a position where all of the input side oil chamber 35, the output side oil chamber 45 and the output side plunger hole 41 are blocked, and (3) an input. It is possible to take a total of three positions: a position where the side oil chamber 35 and the output side plunger hole 41 communicate with each other and the output side oil chamber 45 and the output side plunger hole 41 are blocked.

  The relationship between the length of the merging portion 46 and the length of the enlarged diameter portion 11a in the longitudinal direction of the output-side spool valve 11 is appropriately selected according to the drive characteristics of the hydraulic device of the present invention. Thus, the present invention is not limited to the case where the length of the merging portion 46 and the length of the enlarged diameter portion 11a in the longitudinal direction of the output side spool valve 11 are configured to be substantially the same. That is, in the longitudinal direction of the output side spool valve 11, the merging portion 46 may be longer or shorter than the enlarged diameter portion 11a.

  Hereinafter, the spacer 50 will be described in detail with reference to FIGS. 1 and 2. The spacer 50 is a substantially cylindrical member, and is fitted on the input shaft 2 on the output side swash plate 12 side of the cylinder block 7. The front end surface of the spacer 50 abuts on the output side end surface 7 b of the cylinder block 7, and the rear end surface of the spacer 50 abuts on the inner ring of the output side conical roller bearing 51 fitted on the input shaft 2. At this time, the inner ring of the output side conical roller bearing 51 and the spacer 50 press the output side end surface 7b of the cylinder block 7 forward by the output side bearing tightening nut 53 screwed to the rear end of the input shaft 2. Become. Therefore, the input side end face 7 a of the cylinder block 7 is pressed against the step provided on the input shaft 2, and the cylinder block 7 is fixed to the input shaft 2.

Hereinafter, the output side bearing housing 14 which is a bearing member that pivotally supports the second rotating shaft in the present embodiment will be described in detail with reference to FIG.
The output-side bearing housing 14 has a configuration in which a flange portion 14a is formed at the peripheral portion of a body portion 14b that is a substantially cylindrical member provided with a through-hole penetrating the output shaft 13 in the center. Bolt holes for fixing the hydraulic continuously variable transmission 1 to a transmission case or the like are formed in the flange portion 14a. In the case of the present embodiment, the flange portion 14a is fixed to the transmission housing case 24 that houses the transmission of the work vehicle by bolt fastening.
A ball bearing 54 is fitted to the front end portion of the through hole of the output side bearing housing 14, and the output shaft 13 is pivotally supported via the ball bearing 54. An oil seal 55 is interposed between the rear end portion of the through hole of the output side bearing housing 14 and the output shaft 13, and a contact portion between the outer peripheral surface of the body portion 14 b and the output side bearing housing 14. An O-ring is interposed between the two. As described above, the hydraulic oil leaks out of the transmission housing case 24 from the clearance between the through hole of the output housing 14 and the output shaft 13 and the contact portion between the output bearing housing 14 and the transmission housing case 24. This prevents foreign matter such as dust from entering the transmission housing case 24 and the hydraulic continuously variable transmission 1.

Hereinafter, the output shaft 13 which is the second rotation shaft in this embodiment will be described in detail with reference to FIG.
The output shaft 13 is a shaft for outputting the driving force transmitted to the hydraulic continuously variable transmission 1 by the input shaft 2 to the outside after shifting by the hydraulic continuously variable transmission 1. The output shaft 13 includes a body portion 13b and a flange portion 13a. The output shaft 13 is disposed behind the input shaft 2, and the input shaft 2 and the output shaft 13 are disposed so that the axes thereof are in a straight line.
The body portion 13b has a substantially cylindrical shape, and a ball bearing 54 is fitted on the body portion 13b so as to be rotatably supported by the output side housing 14. The rear end portion of the body portion 13 b protrudes rearward of the output side housing 14. The flange portion 13a is a substantially disk-shaped member provided at the front end portion of the body portion 13b, and a bolt hole for connecting to the output side swash plate 12 is formed.

Hereinafter, the output side swash plate 12 which is the second swash plate in the present embodiment will be described in detail with reference to FIGS. 1, 2, 7 and 8.
The output-side swash plate 12 converts a force for reciprocating the output-side plunger 10 (that is, the pressure of hydraulic oil in the hydraulic circuit formed in the cylinder block 7) into a rotational driving force for the output shaft 13. . The output-side swash plate 12 is a substantially cylindrical member provided with a through-hole through which the input shaft 2 (strictly, the spacer 50 fitted on the input shaft 2) passes, and a swash plate surface 12a is provided at the front portion thereof. Is provided. The swash plate surface 12a is a flat surface, and the protruding end (contact plate 10c) of the output side plunger 10 contacts the swash plate surface 12a. The swash plate surface 12 a forms a predetermined inclination angle (an angle formed between the swash plate surface 12 a and the input shaft 2) with respect to the axis of the input shaft 2.
The rear end of the output side swash plate 12 is fixed to the flange portion 13a of the output shaft 13 by bolt fastening, and the output side swash plate 12 and the output shaft 13 rotate integrally. An outer ring of the output side conical roller bearing 51 is fitted at the rear end of the through hole of the output side swash plate 12, and the output side needle roller bearing 52 is interposed between the through hole of the output side swash plate 12 and the spacer 50. Therefore, the output side swash plate 12 can rotate relative to the input shaft 2.

Hereinafter, the input side spool valve guide 37 and the output side spool valve which are spool valve guides in the first embodiment of the hydraulic apparatus of the present invention will be described with reference to FIGS. 1, 2, 5, 6, 7 and 8. The guide 47 will be described in detail.
In this embodiment, the input-side spool valve guide 37 and the output-side spool valve guide 47 have the same shape for sharing components, but the present invention is not limited to this, and the input-side spool valve guide 37 and the output-side spool valve guide 47 are not limited thereto. The guide 47 may have a different shape.

The input-side spool valve guide 37 is formed by performing various machining on the outer peripheral surface and inner peripheral surface of a substantially cylindrical member, and in cooperation with the rotation of the input shaft 2 (cylinder block 7), 9 is reciprocated. The input-side spool valve guide 37 is loosely fitted to the input shaft 2 and also has a rear end portion of the body portion 4b of the input-side bearing housing 4 that is a bearing member that pivotally supports the input shaft 2 that is the first rotation shaft. The cylinder block 7 is interposed between the input side end face 7a. On the surface where the input side spool valve guide 37 and the input side bearing housing 4 abut, the input side spool valve guide 37 is formed with recesses 37a and 37a, and the rear end surface of the body portion 4b is formed with protrusions 4c and 4c. . The input side spool valve guide 37 cannot be rotated relative to the input shaft 2 by engaging the concave portions 37a and 37a with the convex portions 4c and 4c. The convex portions 4c and 4c and the concave portions 37a and 37a have a substantially trapezoidal shape, and have a surface that is inclined with respect to the axis of the input shaft 2 (not parallel to a surface orthogonal to the axis of the input shaft 2). Yes.
When the input side spool valve guide 37 tries to rotate with the rotation of the input shaft 2 and the cylinder block 7, the surfaces of the convex portions 4c and 4c and the concave portions 37a and 37a that are inclined with respect to the axis of the input shaft 2 are in contact with each other. As a result, a force is generated to press the input side spool valve guide 37 in a direction in which the input side spool valve guide 37 abuts against the input side end surface 7 a of the cylinder block 7.
Therefore, when the hydraulic continuously variable transmission 1 is in operation (when the input shaft 2 is rotating), the input side spool valve guide 37 can be prevented from rotating with the cylinder block 7 and the input side spool valve guide 37 is always kept in contact with the cylinder block 7. Since it is pressed against the input side end face 7a of the cylinder block 7, the distance between the guide groove 37b formed in the input side spool valve guide 37 and the input side end face 7a is accurately maintained.
Even if a convex portion is formed on the input side spool valve guide 37 and a concave portion is formed on the bearing housing 4, substantially the same effect can be obtained.

A guide groove 37 b is formed in a ring shape on the outer peripheral surface of the input side spool valve guide 37. An imaginary plane passing through the guide groove 37b is not perpendicular to the axis of the input side spool valve guide 37 (substantially coincides with the axis of the input shaft 2) and is inclined. Therefore, the distance between the guide groove 37 b and the contact surface 37 c that is a surface that contacts the cylinder block 7 varies depending on the position on the outer peripheral surface of the input-side spool valve guide 37. The contact surface 37 c is orthogonal to the axis of the input shaft 2.
The input side holding member 38 is a substantially ring-shaped member, and is loosely fitted in the guide groove 37b of the input side spool valve guide 37 so as to be rotatable. The number of holding grooves 38a, 38a,... Corresponding to the number of input side spool valves 9, 9,. .. Are engaged with the holding grooves 38a, 38a...
The input side holding member pressing member 39 is a substantially ring-shaped member that holds the input side holding member 38 so as not to drop out from the guide groove 37 b of the input side spool valve guide 37.

A hydraulic oil groove 37d is formed on the inner peripheral surface of the input side spool valve guide 37 in the circumferential direction. The hydraulic oil accumulated in the hydraulic oil groove 37d is contacted between the contact surface 37c and the input side end face 7a of the cylinder block 7. Supply grooves 37e, 37e,... For supplying and lubricating the contact portion are provided.
Further, hydraulic oil holes 37f and 37f communicating with the hydraulic oil groove 37d and the guide groove 37b are formed, and the hydraulic oil accumulated in the hydraulic oil groove 37d by the hydraulic oil holes 37f and 37f is retained in the guide groove 37b and the input side. The abutting portions of the member 38, the input side holding member press 39 and the input side spool valves 9, 9... Are lubricated to prevent wear and maintain the dimensional accuracy of each member.

  When the input shaft 2 makes one rotation with respect to the input side bearing housing 4 fixed to the transmission housing case 24, the cylinder block 7 also makes one rotation with respect to the input side bearing housing 4. Accordingly, the input-side spool valves 9, 9... That are engaged with the guide groove 37b by the input-side holding member 38 make one round of the outer peripheral surface of the input-side spool valve guide 37 along the guide groove 37b. At this time, the virtual plane formed by the guide groove 37b is not parallel to the plane orthogonal to the axis of the input shaft 2 but is inclined, so that the input side spool valves 9, 9. Will reciprocate once.

In the input side spool valve guide 37, a part that requires particularly high dimensional accuracy (or flatness) in order to maintain the accuracy of reciprocation (projection amount) of the input side spool valves 9, 9. Of the input side and the input side holding member 38 with which the engaging portions 9d, 9d,... Of the input side spool valves 9, 9. Only 37b contributes to a reduction in manufacturing cost.
Since the number of members related to the reciprocation accuracy can be reduced, it is possible to reduce the accumulation of machining errors of each member (that is, improve the reciprocation accuracy).

The output-side spool valve guide 47 is formed by performing various machining on the outer peripheral surface and inner peripheral surface of a substantially cylindrical member, and is used for relative rotation between the input shaft 2 (cylinder block 7) and the output shaft 13. The output side spool valves 11, 11... The output-side spool valve guide 47 is a member that is loosely fitted to the front end portion of the outer peripheral surface of the spacer 50 that rotates integrally with the input shaft 2 and rotates integrally with the output shaft 13 that is the second rotation shaft. It is interposed between the contact surface 12 b formed at the front end of the output side swash plate 12 and the output side end surface 7 b of the cylinder block 7. In the surface where the output side spool valve guide 47 and the output side swash plate 12 abut, the output side spool valve guide 47 has recesses 47a and 47a, and the contact surface 12b formed at the front end of the output side swash plate 12 Protrusions 12c and 12c are formed. By engaging the concave portions 47a and 47a with the convex portions 12c and 12c, the output-side spool valve guide 47 cannot rotate relative to the output-side swash plate 12, and rotates integrally with the output-side swash plate 12. . Further, the convex portions 12c and 12c and the concave portions 47a and 47a have a substantially trapezoidal shape, and have surfaces that are inclined with respect to the axis of the input shaft 2 (not parallel to the surface orthogonal to the axis of the input shaft 2). Yes.
When the output side spool valve guide 47 tries to rotate relative to the output side swash plate 12 as the input shaft 2 and the cylinder block 7 rotate, the convex portions 12c and 12c and the concave portions 47a and 47a have the input shaft 2 Due to the contact between the surfaces inclined with respect to the axis, a force is generated to press the output-side spool valve guide 47 in a direction to contact the output-side end surface 7 b of the cylinder block 7.
Therefore, when the hydraulic continuously variable transmission 1 is operated (when the input shaft 2 and the output shaft 13 are rotated), the output side spool valve guide 47 can be prevented from rotating with the cylinder block 7 and the output side spool valve. Since the guide 47 is always pressed against the output side end surface 7b of the cylinder block 7, the distance between the guide groove 47b formed in the output side spool valve guide 47 and the output side end surface 7b is accurately maintained.
Even if a convex portion is formed on the output-side spool valve guide 47 and a concave portion is formed on the output-side swash plate 12, substantially the same effect can be obtained.

A guide groove 47 b is formed in a ring shape on the outer peripheral surface of the output side spool valve guide 47. A virtual plane passing through the guide groove 47b is not perpendicular to the axis of the output-side spool valve guide 47 (substantially coincides with the axis of the input shaft 2) and is inclined. Therefore, the distance between the guide groove 47 b and the contact surface 47 c that is a surface that contacts the cylinder block 7 varies depending on the position on the outer peripheral surface of the output-side spool valve guide 47. The contact surface 47 c is orthogonal to the axis of the input shaft 2.
The output side holding member 48 is a substantially ring-shaped member, and is loosely fitted in the guide groove 47 b of the output side spool valve guide 47 so as to be rotatable. A number of holding grooves 48a, 48a,... Corresponding to the number of output side spool valves 11, 11,. .. Are engaged with the holding grooves 48a, 48a...
The output-side holding member holding member 49 is a substantially ring-shaped member that holds the output-side holding member 48 so as not to drop out of the guide groove 47 b of the output-side spool valve guide 47.

A hydraulic oil groove 47d is formed in the circumferential direction on the inner peripheral surface of the output-side spool valve guide 47, and the hydraulic oil accumulated in the hydraulic oil groove 47d is contacted between the contact surface 47c and the output-side end surface 7b of the cylinder block 7. Supply grooves 47e, 47e,... For supplying and lubricating the contact portion are provided.
Further, hydraulic oil holes 47f and 47f communicating the hydraulic oil groove 47d and the guide groove 47b are formed, and the hydraulic oil accumulated in the hydraulic oil groove 47d by the hydraulic oil holes 47f and 47f is retained in the guide groove 47b and the output side. The abutting portions of the member 48, the output side holding member press 49 and the output side spool valves 11, 11,... Are lubricated to prevent wear and maintain the dimensional accuracy of each member.

  When the output shaft 13 makes one rotation relative to the input shaft 2, the output side spool valves 11, 11... Engaged with the guide groove 47 b by the output side holding member 48 are The outer peripheral surface of the output-side spool valve guide 47, which cannot be relatively rotated, goes around the guide groove 47b. At this time, the virtual plane formed by the guide groove 47b is not parallel to the plane orthogonal to the axis of the input shaft 2 but is inclined, so that the output side spool valves 11, 11. Will reciprocate once.

In the output side spool valve guide 47, a part that requires particularly high dimensional accuracy (or flatness) in order to maintain the accuracy of the reciprocating motion (projection amount) of the output side spool valves 11, 11,. Of the output side end face 7b, and the guide groove in which the output side holding member 48 to which the engaging portions 11d of the output side spool valves 11, 11. Only 47b contributes to a reduction in manufacturing cost.
Since the number of members related to the reciprocation accuracy can be reduced, it is possible to reduce the accumulation of machining errors of each member (that is, improve the reciprocation accuracy).

Hereinafter, the charge circuit will be described in detail with reference to FIGS.
The charge circuit replenishes hydraulic oil pumped from a hydraulic pump (not shown) provided outside the hydraulic continuously variable transmission 1 to the hydraulic closed circuit in the cylinder block 7 and is hydraulically continuously variable. Lubricating the contact portion between the members of the transmission 1.

  An insertion hole 70 is formed in the front surface of the flange portion 4 a of the input side bearing housing 4, and a hydraulic pipe that connects a hydraulic pump (not shown) and a charge circuit is connected to the insertion hole 70. The insertion hole 70 penetrates to the rear surface of the flange portion 4a of the input side bearing housing 4, and one end of a communication hole 71 formed in the attachment portion 5a of the swash plate holding member 5 that contacts the rear surface of the flange portion 4a. Communicated with. The other end of the communication hole 71 opens toward the inner peripheral surface of the mounting portion 5a of the swash plate holding member 5, and is drilled in the body portion 4b of the bearing housing 4 that contacts the inner peripheral surface of the mounting portion 5a. The communication hole 72 communicates with one end. The other end of the communication hole 72 communicates with the inner peripheral surface of the through hole of the body portion 4b.

  Further, the communication hole 72 branches back and forth at a midway portion, and hydraulic oil is supplied to the input side conical roller bearing 21 through an oil passage branched forward and lubrication is performed. The working oil after lubricating the input side conical roller bearing 21 is returned into the transmission housing case 24 through a return oil passage 73 formed in the input side bearing housing 4. On the other hand, the communication hole 72 is lubricated by supplying hydraulic oil to the input side needle roller bearing 22 through an oil passage branched backward in the middle. Then, hydraulic oil is supplied between the outer peripheral surface of the input shaft 2 and the inner peripheral surface of the input-side spool valve guide 37 through an oil hole (not shown) communicating with the supply hole 2b of the input shaft 2, and lubrication is performed. . The hydraulic oil after lubricating the input side needle roller bearing 22 and the input side spool valve guide 37 is returned to the transmission housing case 24.

  A ring-shaped introduction groove 73 is formed in the input shaft 2 at a position facing the other end of the communication hole 72 communicating with the inner peripheral surface of the through hole of the body portion 4b.

  The input shaft 2 is provided with a supply hole 2b in the axial direction from the center of the front end surface thereof. The rear end of the supply hole 2b is a position corresponding to the front end portion of the inner ring of the output-side conical roller bearing 51, and an oil passage 2c that connects the rear end of the supply hole 2b and the outer peripheral surface of the input shaft 2 is formed. Is done. The front end of the supply hole 2 b is closed by a seal plug 76. The input shaft 2 is provided with a communication hole 77 that communicates the introduction groove 73 and the supply hole 2b.

The input shaft 2 is provided with an input side communication hole 78 that allows the supply hole 2 b and the input side oil chamber 35 to communicate with each other, and an input side check valve 79 is provided in the middle of the communication hole 78. The input shaft 2 is provided with an output side communication hole 80 that communicates the supply hole 2b and the output side oil chamber 45, and an input side check valve 81 is provided in the middle of the communication hole 80. It is done.
The input-side check valve 79 prevents the backflow of hydraulic oil from the input-side oil chamber 35 to the supply hole 2b, and the output-side check valve 81 operates from the output-side oil chamber 45 to the supply hole 2b. It prevents oil backflow.
The output-side oil chamber 45 overlaps with a spline portion (portion where the cylinder block 7 is splined) formed on the input shaft 2, and a part of the hydraulic oil in the output-side oil chamber 45 is placed on the spline portion. Leakage and lubrication.

The oil passage 2 c communicates with an oil passage 50 a formed on the rear end surface of the spacer 50. Accordingly, the hydraulic oil is supplied to the output side needle roller bearing 52 and the output side spool valve guide 47 through the oil passage 50a to perform lubrication. In addition, hydraulic oil is supplied between the outer peripheral surface of the spacer 50 and the inner peripheral surface of the output-side spool valve guide 47 through an oil hole (not shown) that penetrates the spacer 50 and communicates with the supply hole 2 b of the input shaft 2. Lubrication. The hydraulic oil after lubricating the output side roller bearing 52 and the output side spool valve guide 47 is returned into the transmission housing case 24.
Further, the hydraulic oil is supplied to the output side conical roller bearing 51 through the oil passage 50a to perform lubrication. The hydraulic oil after lubricating the output-side conical roller bearing 51 is supplied to the ball bearing 54 via the return oil passages 13c and 13c drilled in the output shaft 13, lubricates the ball bearing 54, and the transmission housing case 24. Returned in.

  As described above, the insertion hole 70, the communication hole 71, the communication hole 72, the introduction groove 73, the communication hole 77, and the supply hole 2 b are provided from a hydraulic pump (not shown) provided outside the hydraulic continuously variable transmission 1. As a result, hydraulic oil (shortage) is supplied from the input side communication hole 78 or the output side communication hole 80 to the hydraulic closed circuit in the cylinder block 7.

  The configuration of the charge circuit is not limited to the present embodiment, and hydraulic oil can be supplied to the hydraulic closed circuit in the cylinder block 7 and supplied to the contact points between the members of the hydraulic continuously variable transmission 1. I just need it.

Hereinafter, an assembling method of the hydraulic continuously variable transmission 1 according to this embodiment will be described with reference to FIGS. 1 and 2.
First, the cylinder block 7 is inserted into the input shaft 2 from the rear end thereof until the input side end surface 7a of the cylinder block 7 comes into contact with a step provided in the middle portion of the input shaft 2. At this time, the cylinder block 7 and the input shaft 2 are spline-fitted.
Next, the spacer 50 is inserted into the input shaft 2 from the rear end portion, and the output side spool valve guide 47 is loosely fitted to the spacer 50.
Subsequently, the output side holding member 48 and the output side holding member presser 49 are attached to the output side spool valve guide 47, and the output side spool valves 11, 11. Are engaged with the output-side spool valve holes 42, 42,... With the engaging portions 11d, 11d,. .. Are housed in the output side plunger holes 41, 41,... Together with the spring retainers 29, 29,.

  Then, after the outer rings of the output side needle roller bearing 52 and the output side conical roller bearing 51 are fitted to the output side swash plate 12, the outer ring is inserted into the outer periphery of the spacer 50, and the inner ring of the output side conical roller bearing 51 is inserted into the rear of the spacer 50. It is fitted while being brought into contact with the end face, and is fastened by the output side bearing fastening nut 53.

  Subsequently, the input side holding member 38 and the input side holding member presser 39 are attached to the input side spool valve guide 37, and the input side spool valves 9, 9. Are engaged with the input side spool valve holes 32, 32,... With the engaging portions 9d, 9d,. In addition, the input side plungers 8, 8... Are accommodated in the input side plunger holes 31, 31.

Next, the swash plate holding member 5 and the input side needle roller bearing 22 are attached to the input side bearing housing 4 in advance, and the input side swash plate 6 is brought into contact with the input side plungers 8, 8. The side bearing housing 4 is inserted through the input shaft 2 from the front end portion of the input shaft 2. At this time, the holding portions 6b and 6b of the input side swash plate 6 are rotatably fitted to the holding portions 5b and 5b of the swash plate holding member 5.
The holding portions 6b and 6b of the input side swash plate 6 are fitted in advance to the holding portions 5b and 5b of the swash plate holding member 5 so as to be rotatable, and then the swash plate holding member 5 and the input side needle roller bearings. The input-side bearing housing 4 to which 22 is attached may be inserted through the input shaft 2 from the front end portion of the input shaft 2.

Subsequently, the outer ring of the input side conical roller bearing 21 is fitted into the input side bearing housing 4, and the inner ring of the input side conical roller bearing 21 is fitted until it engages with a step provided on the outer peripheral surface of the input shaft 2. The input side bearing fastening nut 23 is used for fastening.
Further, the input side housing lid 3 and the input side bearing are inserted after the oil seal 25 and the retaining ring 26 are interposed between the input side housing lid 3 and the input side housing 4 while abutting from the front end side of the input shaft 2. The housing 4 is fastened with bolts.

  Finally, the output shaft 13 and the output side swash plate 12 that are previously inserted in the output side bearing housing 14 via the ball bearings 54 are bolted.

  As described above, in the hydraulic continuously variable transmission 1 of the present embodiment, the force acting in the axial direction of the input shaft 2 generated by the input side plungers 8,... Is the input side swash plate 6 and the input side cone. It is transmitted only to the input shaft 2 through the roller bearing 21. Further, the force generated in the axial direction of the input shaft 2 generated by the output side plungers 10, 10... Is transmitted only to the input shaft 2 through the output side swash plate 12 and the output side conical roller bearing 51. With this configuration, the force generated in the axial direction of the input shaft 2 by the input-side plungers 8,... And the output-side plungers 10, 10. Noise is reduced because it is not a vibration source for cases and the like.

In the following, the hydraulic closed circuit of the hydraulic continuously variable transmission 1 and the mechanism of speed change by the hydraulic oil in the hydraulic closed circuit will be described in detail with reference to FIGS. 2, 3, 9, 10, 11 and 12. .
As shown in FIGS. 2 and 3, in the cylinder block 7 of the hydraulic continuously variable transmission 1, there are an input side plunger hole 31, an input side spool valve hole 32, a communication hole 33, an input side oil chamber 35, and a merging portion 36. A closed hydraulic circuit including the output side plunger hole 41, the output side spool valve hole 42, the communication hole 43, the output side oil chamber 45, the merging portion 46, and the like is formed.
The input-side plunger hole 31 communicates with the input-side oil chamber 35 and the output-side oil chamber 45 via the communication hole 33 and the input-side spool valve hole 32, and the output-side plunger hole 41 has the communication hole 43 and the output-side spool valve hole. The hydraulic closed circuit communicates the input-side plunger hole 31 and the output-side plunger hole 41 because the input-side oil chamber 35 and the output-side oil chamber 45 communicate with each other via 42.

  In the following description, the hydraulic continuously variable transmission 1 according to the present embodiment is referred to as “forward rotation” when rotating clockwise (rotating clockwise) when viewed in the axial direction from the front of the input shaft 2. The swash plate 6 is rotated up and down (the perpendicular of the swash plate surface 6a of the input side swash plate 6 changes the tilt angle up and down with respect to the axis of the input shaft 2). For convenience of explanation, it is assumed that the input shaft 2 is rotating forward at a substantially constant rotational speed (Nin> 0).

The amount of protrusion of the input side plunger 8 and the output side plunger 10 from the cylinder block 7 is “positive” when the plunger protrudes from the cylinder block 7, and “negative” when the plunger is inserted into the cylinder block 7.
The amount of protrusion of the input-side spool valve 9 and the output-side spool valve 11 from the cylinder block 7 is such that the position where the spool valve closes both the input-side oil chamber 35 and the output-side oil chamber 45 (neutral position) is zero. The side protruding from the block 7 is “positive”, and the side immersing into the cylinder block 7 is “negative”.
As shown in FIGS. 9 and 10, the position where the protruding amount of the input side spool valve 9 from the cylinder block 7 is the largest (the top dead center 102 of the input side spool valve 9) is the axial direction from the front of the input shaft 2. The position where the protrusion amount of the input side spool valve 9 from the cylinder block 7 is minimized (the bottom dead center 112 of the input side spool valve 9) is the right side of the hydraulic continuously variable transmission 1 as viewed. The left side of the hydraulic continuously variable transmission 1 is seen from the front in the axial direction.
The position at which the protruding amount of the output side spool valve 11 from the cylinder block 7 is the largest (the top dead center 104 of the output side spool valve 11) is the position of the output side swash plate 12 when viewed from the front of the input shaft 2 in the axial direction. It is assumed that the swash plate surface 12a is rotated 90 degrees counterclockwise (counterclockwise) from a position where the swash plate surface 12a is farthest from the cylinder block 7 (a position where the output side plunger 10 protrudes most from the cylinder block 7). The position where the protrusion amount of the output side spool valve 11 from the cylinder block 7 is minimized (the bottom dead center 114 of the output side spool valve 11) is the position of the output side swash plate 12 when viewed from the front of the input shaft 2 in the axial direction. A position rotated 90 degrees clockwise (clockwise) from a position where the swash plate surface 12a is closest to the cylinder block 7 (a position where the output side plunger 10 protrudes most from the cylinder block 7).

Hereinafter, with reference to FIG. 9, “speed increasing operation” (where the rotational speed of the input shaft 2 is Nin, the rotational speed of the output shaft 13 is Nout, and a speed change operation is performed so that | Nin | <| Nout |). The flow of hydraulic oil in the hydraulic closed circuit will be described in detail.
During the speed increasing operation, the input side swash plate 6 is rotated so that the top dead center 101 of the input side plunger 8 is located above the hydraulic continuously variable transmission 1.

  FIG. 9A shows the positional relationship between the protruding amount of the input side plunger 8 and the protruding amount of the input side spool valve 9 when viewed in the axial direction from the front of the input shaft 2, and the cylinder relative to the input side swash plate 6. The rotation direction of the block 7 (input shaft 2) and the flow of hydraulic oil in the hydraulic closed circuit related to the input side plunger 8 are schematically shown.

  When the input side plunger 8 is rotating from the bottom dead center 111 toward the top dead center 101 (represented by a thick dotted line arrow in FIG. 9A and when the input side plunger 8 protrudes from the cylinder block 7) The input side spool valve 9 has moved to the bottom dead center 112 side of the input side spool valve 9. Therefore, the input-side plunger hole 31 and the input-side oil chamber 35 communicate with each other, and hydraulic oil flows from the input-side oil chamber 35 into the input-side plunger hole 31.

  When the input side plunger 8 is rotating from the top dead center 101 toward the bottom dead center 111 (represented by a thick solid arrow in FIG. 9A, when the input side plunger 8 is immersed in the cylinder block 7) The input side spool valve 9 has moved to the top dead center 102 side of the input side spool valve 9. Accordingly, the input side plunger hole 31 and the output side oil chamber 45 communicate with each other, and the hydraulic oil is discharged from the input side plunger hole 31 to the output side oil chamber 45.

  If it demonstrates using FIG. 11, the input side spool valve 9 corresponding to the input side plunger hole 31 which is discharging | emitting hydraulic fluid will be located in (B), (C), (D), and hydraulic fluid will flow in The input-side spool valve 9 corresponding to the input-side plunger hole 31 is located at (E), (F), (G). In addition, the input side spool valve 9 located in (A) is just in the neutral position, and the input side plunger hole 31 corresponding to the input side spool valve 9 is cut off from the hydraulic closed circuit.

  As described above, during the speed increasing operation, the closed hydraulic circuit related to the input side plunger 8 flows from the input side oil chamber 35 into some of the input side plunger holes 31 and outputs from the other input side plunger holes 31. The hydraulic oil is discharged into the side oil chamber 45.

FIG. 9B shows the positional relationship between the protruding amount of the output-side plunger 10 and the protruding amount of the output-side spool valve 11 when viewed in the axial direction from the front of the input shaft 2, and the cylinder with respect to the output-side swash plate 12. The rotation direction of the block 7 (input shaft 2) and the flow of hydraulic oil in the hydraulic closed circuit related to the output side plunger 10 are shown.
At the time of speed increasing operation, the output shaft 13 has the same rotational direction as the input shaft 2 and has a large rotational speed (| Nin | <| Nout |). Therefore, when the output side swash plate 12 is used as a reference, the cylinder block 7 is relatively Appears to be reversed (rotated counterclockwise).

  When the output-side plunger 10 is rotating from the bottom dead center 113 toward the top dead center 103 (represented by a thick dotted arrow in FIG. 9B, when the output-side plunger 10 protrudes from the cylinder block 7) The output side spool valve 11 has moved to the bottom dead center 114 side of the output side spool valve 11. Therefore, the output side plunger hole 41 and the output side oil chamber 45 communicate with each other, and the working oil flows from the output side oil chamber 45 toward the output side plunger hole 41.

  When the output-side plunger 10 is rotating from the top dead center 103 toward the bottom dead center 113 (represented by a thick solid line arrow in FIG. 9B, when the output-side plunger 10 is immersed in the cylinder block 7) The output side spool valve 11 has moved to the top dead center 104 side of the output side spool valve 11. Accordingly, the output side plunger hole 41 and the input side oil chamber 35 communicate with each other, and the hydraulic oil is discharged from the output side plunger hole 41 toward the input side oil chamber 35.

  If it demonstrates using FIG. 11, the output side spool valve 11 corresponding to the output side plunger hole 41 which is discharging | emitting hydraulic fluid will be located in (ii), (iii), (iv), and hydraulic fluid will flow in The output-side spool valve 11 corresponding to the inner output-side plunger hole 41 is located at (v), (vi), (vii). The output-side spool valve 11 located at (i) is just in the neutral position, and the output-side plunger hole 41 corresponding to the output-side spool valve 11 is cut off from the hydraulic closed circuit.

As described above, during the speed increasing operation, the closed hydraulic circuit related to the output-side plunger 10 flows from the output-side oil chamber 45 into some of the output-side plunger holes 41 and from the other output-side plunger holes 41. The hydraulic oil is discharged into the input side oil chamber 35.
Accordingly, during the speed increasing operation, as shown in FIG. 12, in the hydraulic closed circuit in the cylinder block 7, the input side hydraulic device 56 → the input side oil chamber 35 → the output side hydraulic device 57 → the output side oil chamber 45 → the input side. The flow of hydraulic oil in the hydraulic device 56 (more strictly speaking, the input side plunger hole 31 → the communication hole 33 → the merging portion 36 → the input side spool valve hole 32 → the input side oil chamber 35 → the output side spool valve hole 42 → the communication hole. 42 → Flow of hydraulic oil such as output-side plunger hole 41, output-side plunger hole 41 → communication hole 42 → output-side spool valve hole 42 → output-side oil chamber 45 → input-side spool valve hole 32 → merging portion 36 → communication hole 33 → input side plunger hole 31 combined with the flow of hydraulic oil). The input-side hydraulic device 56 refers to the input-side plungers 8, 8,..., The input-side spool valves 9, 9,. ..., the input-side spool valves 11, 11, ... and a mechanism for reciprocating them.

In the following, referring to FIG. 10, the hydraulic pressure at the time of “deceleration operation” (shifting operation so that | Nin |> | Nout | is established, where the rotational speed of the input shaft 2 is Nin and the rotational speed of the output shaft 13 is Nout). The flow of hydraulic oil in the closed circuit will be described in detail.
During the deceleration operation, the input side swash plate 6 is rotated so that the top dead center 101 of the input side plunger 8 is located below the hydraulic continuously variable transmission 1.

  FIG. 10A shows the positional relationship between the protruding amount of the input side plunger 8 and the protruding amount of the input side spool valve 9 when viewed in the axial direction from the front of the input shaft 2 and the cylinder with respect to the input side swash plate 6. The rotation direction of the block 7 (input shaft 2) and the flow of hydraulic oil in the hydraulic closed circuit related to the input side plunger 8 are schematically shown.

  When the input side plunger 8 is rotating from the bottom dead center 111 toward the top dead center 101 (represented by a thick dotted arrow in FIG. 10A, when the input side plunger 8 protrudes from the cylinder block 7) The input side spool valve 9 has moved to the top dead center 102 side of the input side spool valve 9. Accordingly, the input side plunger hole 31 and the output side oil chamber 45 communicate with each other, and the working oil flows from the output side oil chamber 45 into the input side plunger hole 31.

  When the input-side plunger 8 is rotating from the top dead center 101 toward the bottom dead center 111 (indicated by a thick solid arrow in FIG. 10A, when the input-side plunger 8 is immersed in the cylinder block 7) The input side spool valve 9 has moved to the bottom dead center 112 side of the input side spool valve 9. Therefore, the input side plunger hole 31 and the input side oil chamber 35 communicate with each other, and the hydraulic oil is discharged from the input side plunger hole 31 to the input side oil chamber 35.

  If it demonstrates using FIG. 11, the input side spool valve 9 corresponding to the input side plunger hole 31 which is discharging | emitting hydraulic fluid will be located in (E), (F), (G), and hydraulic fluid will flow in The input-side spool valve 9 corresponding to the input-side plunger hole 31 is located at (B), (C), (D). In addition, the input side spool valve 9 located in (A) is just in the neutral position, and the input side plunger hole 31 corresponding to the input side spool valve 9 is cut off from the hydraulic closed circuit.

  As described above, during the deceleration operation, the closed hydraulic circuit related to the input side plunger 8 flows from the output side oil chamber 45 into some of the input side plunger holes 31 and the other input side plunger holes 31 to the input side. The hydraulic oil is discharged into the oil chamber 35.

FIG. 10B shows the positional relationship between the protruding amount of the output-side plunger 10 and the protruding amount of the output-side spool valve 11 when viewed from the front of the input shaft 2 in the axial direction, and the cylinder with respect to the output-side swash plate 12. The rotation direction of the block 7 (input shaft 2) and the flow of hydraulic oil in the hydraulic closed circuit related to the output side plunger 10 are shown.
During the deceleration operation, the output shaft 13 has the same rotational direction as the input shaft 2 and the rotational speed is small (| Nin |> | Nout |). Appears to rotate forward (clockwise).

  When the output-side plunger 10 is rotating from the bottom dead center 113 toward the top dead center 103 (represented by a thick dotted arrow in FIG. 10B, when the output-side plunger 10 protrudes from the cylinder block 7) The output side spool valve 11 has moved to the top dead center 104 side of the output side spool valve 11. Therefore, the output side plunger hole 41 and the input side oil chamber 35 communicate with each other, and the working oil flows from the input side oil chamber 35 toward the output side plunger hole 41.

  When the output side plunger 10 is rotating from the top dead center 103 toward the bottom dead center 113 (represented by a thick solid line arrow in FIG. 10B, when the output side plunger 10 is immersed in the cylinder block 7). The output side spool valve 11 has moved to the bottom dead center 114 side of the output side spool valve 11. Accordingly, the output side plunger hole 41 and the output side oil chamber 45 communicate with each other, and the hydraulic oil is discharged from the output side plunger hole 41 toward the output side oil chamber 45.

  If it demonstrates using FIG. 11, the output side spool valve 11 corresponding to the output side plunger hole 41 which is discharging | emitting hydraulic fluid will be located in (v), (vi), (vii), and hydraulic fluid will flow in The output-side spool valve 11 corresponding to the output-side plunger hole 41 is located at (ii), (iii), (iv). The output-side spool valve 11 located at (i) is just in the neutral position, and the output-side plunger hole 41 corresponding to the output-side spool valve 11 is cut off from the hydraulic closed circuit.

As described above, during the deceleration operation, the closed hydraulic circuit related to the output-side plunger 10 flows from the input-side oil chamber 35 into some output-side plunger holes 41 and outputs from the other output-side plunger holes 41. The hydraulic oil is discharged into the side oil chamber 45.
Therefore, during deceleration operation, as shown in FIG. 12, in the hydraulic closed circuit in the cylinder block 7, the input side hydraulic device 56 → the output side oil chamber 45 → the output side hydraulic device 57 → the input side oil chamber 35 → the input side hydraulic pressure. The flow of hydraulic fluid in the device 56 (strictly speaking, the input side plunger hole 31 → the communication hole 33 → the junction 36 → the input side spool valve hole 32 → the output side oil chamber 45 → the output side spool valve hole 42 → the communication hole 42) → Flow of hydraulic oil called output side plunger hole 41 and output side plunger hole 41 → communication hole 42 → output side spool valve hole 42 → input side oil chamber 35 → input side spool valve hole 32 → junction portion 36 → communication hole 33 → The input side plunger hole 31 is combined with the flow of hydraulic oil).

In the following, referring to FIG. 2 and FIG. 12, a “constant speed operation” (where the rotational speed of the input shaft 2 is Nin and the rotational speed of the output shaft 13 is Nout is changed so that | Nin | = | Nout | The flow of hydraulic oil in the hydraulic closed circuit will be described in detail.
During constant speed operation, the swash plate surface 6a of the input swash plate 6 and the input side end surface 7a are parallel (the swash plate surface 6a of the input swash plate 6 is orthogonal to the axis of the input shaft 2). The swash plate 6 is rotated.
At this time, the input side plunger 8 does not reciprocate even if the cylinder block 7 rotates relative to the swash plate 6, so that no hydraulic oil flows by the input side plunger 8. That is, in FIG. 12, the circulation of hydraulic oil in the hydraulic circuit is stopped.

Even if the output shaft 13 tries to rotate at a higher speed with respect to the cylinder block 7 at the constant speed operation, the circulation of the hydraulic oil is stopped, so the output-side plunger 10 that tries to discharge the hydraulic oil cannot move in the axial direction. It is.
Similarly, even if the output shaft 13 attempts to rotate at a reduced speed with respect to the cylinder block 7, since the circulation of the hydraulic oil is stopped, the output-side plunger 10 that tries to discharge the hydraulic oil cannot move in the axial direction. .
Therefore, the output shaft 13 cannot rotate relative to the cylinder block 7 during constant speed operation, and the input shaft 2 and the output shaft 13 rotate integrally (with the same rotational speed in the same direction). .

Hereinafter, the shifting action of the hydraulic continuously variable transmission 1 will be described with reference to FIGS. 12 and 13.
In the hydraulic continuously variable transmission 1 of the present invention, the ratio of the rotational speed of the output shaft 13 to the rotational speed of the input shaft 2 within the range of the inclination angle of the swash plate surface 6a that the input-side swash plate 6 can take (= Nout / Nin) can be changed steplessly (stepless speed change).
The normal HST in FIG. 13 indicates an HST (Hydro Static Transmission) in which a hydraulic pump (input-side hydraulic device) and a hydraulic motor (output-side hydraulic device) having substantially the same configuration are paired. The “normal HST” is a fixed type in which the swash plate on the hydraulic motor side has a predetermined tilt angle, and the tilt angle of the swash plate on the hydraulic pump side is the same as the tilt angle of the swash plate of the hydraulic motor. The value can be changed to a positive or negative value.

In the case of normal HST, the rotation speed Nout of the output shaft is expressed by the following (formula 1) using the rotation speed Nin of the input shaft, the stroke volume Vin of the input-side hydraulic device, and the stroke volume Vout of the output-side hydraulic device. Is done.
Nout = Nin × (Vin / Vout) (Formula 1)
Note that the rotational speed Nin of the input shaft in (Equation 1) is zero or a positive value when a normal HST is connected to a drive source such as an engine without a mechanism for forward / reverse conversion of the rotational direction. I take the. The stroke volume Vin of the input-side hydraulic device is the volume of hydraulic fluid that is pumped from the input-side hydraulic device to the output-side hydraulic device when the input shaft makes one revolution, and the stroke volume Vout of the output-side hydraulic device is one revolution of the output shaft. This is the volume of hydraulic oil that is sometimes pumped from the output hydraulic device to the input hydraulic device. Further, the stroke volume Vin of the input side hydraulic device changes depending on the inclination angle of the swash plate on the input side and can take a positive or negative value depending on the pressure feeding direction in the hydraulic circuit, whereas the stroke volume Vin of the output side hydraulic device. The volume Vout is a positive constant because the inclination angle of the swash plate on the output side is fixed to a predetermined value.

As shown in (Equation 1) above, when the stroke volume Vin of the normal HST input-side hydraulic device is zero, that is, the inclination angle of the swash plate of the input-side hydraulic device is orthogonal to the axis of the rotation axis of the cylinder block, When the hydraulic oil is not pumped even when the input-side hydraulic device rotates, the rotation speed Nout of the output shaft of the output-side hydraulic device is also zero.
The stroke volume Vin is obtained while the swash plate of the normal HST input-side hydraulic device is tilted to the forward rotation side (so that the rotation direction of the input shaft and the rotation direction of the output shaft are the same direction) and taking a positive value. When the absolute value of is increased, the rotational speed Nout of the output shaft takes a positive value in proportion to the stroke volume Vin and increases in absolute value. Further, the swash plate of a normal HST input-side hydraulic device is tilted to the reverse side (so that the rotation direction of the input shaft and the rotation direction of the output shaft are opposite directions), and the stroke volume is obtained while taking a negative value. When the absolute value of Vin is increased, the absolute value of the rotational speed Nout of the output shaft increases while taking a negative value in proportion to the stroke volume Vin.
Therefore, the rotational speed Nout of the output shaft in normal HST can take a value of −Nin ≦ Nout ≦ Nin, where the rotational speed of the input shaft is Nin (thick dotted line in FIG. 13).

On the other hand, in the case of the hydraulic continuously variable transmission 1 of the present embodiment, the rotational speed Nout of the output shaft 13 is the rotational speed Nin of the input shaft 2, the relative rotational speed Nr of the output shaft 13 with respect to the cylinder block 7, and the input side. Using the stroke volume Vin of the hydraulic device 56 and the stroke volume Vout of the output-side hydraulic device 57, the following (Expression 2), (Expression 3), and (Expression 4) are expressed.
Nout = Nin + Nr (Formula 2)
Nr = Nin × (Vin / Vout) (Formula 3)
Nout = Nin × (1 + Vin / Vout) (Formula 4)
Note that the rotational speed Nin of the input shaft 2 in (Equation 2), (Equation 3), and (Equation 4) is a mechanism in which the hydraulic continuously variable transmission 1 converts the rotational direction to a drive source such as an engine in the forward and reverse directions. It takes zero or a positive value when connected without intervening. The relative rotational speed Nr of the output shaft 13 with respect to the cylinder block 7 is a positive value when the output shaft 13 is rotating forward with respect to the cylinder block 7, and is a negative value when the output shaft 13 is rotating reversely. . The stroke volume Vin of the input-side hydraulic device 56 is the volume of hydraulic fluid pumped from the input-side hydraulic device 56 to the output-side hydraulic device 57 when the input shaft 2 makes one revolution, and the stroke volume Vout of the output-side hydraulic device 57 is output. This is the volume of hydraulic oil that is pumped from the output side hydraulic device 56 to the input side hydraulic device when the shaft 13 makes one rotation relative to the cylinder block 7. The stroke volume Vin of the input-side hydraulic device 56 varies depending on the inclination angle of the input-side swash plate 6 and can take a positive or negative value depending on the pumping direction in the hydraulic circuit. The stroke volume Vout is a positive constant because the inclination angle of the output side swash plate 12 is fixed to a predetermined value. Furthermore, since the inclination angle of the output-side swash plate 12 and the maximum absolute value of the inclination angle of the input-side swash plate 6 are equal, | Vin max | = Vout is established.

As shown in the above (Formula 2), (Formula 3) and (Formula 4), when the stroke volume Vin of the input side hydraulic device 56 is zero, that is, the swash plate surface 6a of the input side swash plate 6 is The rotation speed Nout of the output shaft 13 of the output-side hydraulic device 57 is equal to that of the input shaft 2 when the hydraulic oil is not pumped even when the input-side hydraulic device 56 rotates even when the input-side hydraulic device 56 rotates. It is equal to the rotational speed Nin.
The input side swash plate 6 is inclined toward the speed increasing side (so that the rotation direction of the input shaft 2 and the rotation direction of the output shaft are the same direction and Nin <Nout), and the absolute value of the stroke volume Vin is obtained while taking a positive value. When the value is increased, the relative rotation speed Nr of the output shaft 13 with respect to the cylinder block 7 takes a positive value in proportion to the stroke volume Vin and increases in absolute value. Further, the input side swash plate 6 is inclined toward the deceleration side (so that the rotation direction of the input shaft 2 and the rotation direction of the output shaft are the same direction and Nin> Nout), and the stroke volume Vin is obtained while taking a negative value. When the absolute value of is increased, the relative rotational speed Nr of the output shaft 13 with respect to the cylinder block 7 takes a negative value in proportion to the stroke volume Vin and increases in absolute value.
Therefore, the rotational speed Nout of the output shaft 13 in the hydraulic continuously variable transmission 1 of the present embodiment can take a value of 0 ≦ Nout ≦ 2 × Nin, where the rotational speed of the input shaft 2 is Nin (in FIG. 13). Thick solid line).

  As described above, in the case of normal HST, by changing the inclination angle of the swash plate of the input side hydraulic device, the output shaft rotation speed is centered on zero and the absolute value is the same as the rotation speed of the input shaft. In the case of the hydraulic continuously variable transmission 1, the rotational speed of the output shaft 13 can be changed by changing the inclination angle of the input side swash plate 6. Centering on Nin, the number of rotations is zero to twice the number of Nin (0 ≦ Nout ≦ 2 × Nin).

Such a configuration has the following advantages. That is, when the normal HST is used under the condition where the output shaft rotation speed Nout is close to Nin, the circulation amount of hydraulic fluid in the hydraulic circuit of the HST is large (| Vin | is large). Therefore, there has been a problem that the energy loss accompanying the temperature rise of the hydraulic oil and the leakage of hydraulic oil from each part of the HST is large.
On the other hand, when the hydraulic continuously variable transmission 1 according to the present embodiment is used under the condition that the rotation speed Nout of the output shaft is close to Nin, the hydraulic oil in the hydraulic circuit of the hydraulic continuously variable transmission 1 is used. Circulation amount is small (| Vin | is small). Therefore, the energy loss accompanying the rise in the temperature of the hydraulic oil and the leakage of the hydraulic oil from each part of the hydraulic continuously variable transmission 1 is small.
Therefore, when the hydraulic continuously variable transmission 1 is applied, by designing the rotational speed Nin of the input shaft 2 to be within the rotational speed range of the output shaft that is frequently used for the purpose of use, an output that is frequently used is output. It is possible to suppress energy loss caused by the hydraulic continuously variable transmission 1 when the output shaft 13 rotates in the shaft rotation speed range, and to improve energy efficiency (fuel consumption).

  As described above, the hydraulic continuously variable transmission 1 that is the first embodiment of the hydraulic apparatus of the present invention includes the input shaft 2 that is the first rotating shaft and the output shaft 13 that is the second rotating shaft, and the axial direction. The input side plungers 8, 8... Which are the first plungers reciprocally moving and the output side plungers 10.10. The input side spool valves 9, 9 ... and the output side spool valves 11, 11 ..., which are the second spool valves, and the input side plungers 8, 8 ..., the output side plungers 10, 10, ... The cylinder block 7 that accommodates the input-side spool valves 9, 9... And the output-side spool valves 11, 11,. On the plate surface 6a, the input side plunger 8 The input side swash plate 6 that is a first swash plate that comes into contact with the output shaft, and an output shaft that is in contact with the output side plungers 10, 10. , And an output side swash plate 12 that rotates integrally with the input side plunger holes 31, 31... Is formed in the cylinder block 7 and communicates with the output side plunger holes 41, 41... By the input side spool valves 9, 9. .. Are switched to the input-side plunger holes 31, 31... For receiving the output-side plungers 10. Enter / exit holes 41, 41 ... The hydraulic oil flow path is configured to be changed from a spool valve guide 37 having a guide groove 37b inclined with respect to the axis, and a spool valve guide 47 having a guide groove 47b similarly inclined with respect to the axis. The input side spool valves 9, 9... Engage with the input side holding member 38, which is a holding member attached to the guide groove 37b, and the output side spool valve 11. 11... Engages with the output side holding member 48 that is a holding member attached to the guide groove 47 b, so that the axes of the input side spool valves 9, 9... And the output side spool valves 11, 11. Components required to have high dimensional accuracy in order to maintain the accuracy of reciprocating motion in the direction (in this embodiment, input side spool valve guide 37, output side spool valve guide 47, cylinder The number of parts in block 7) can be reduced, and the manufacturing cost can be reduced.

  Further, the input side spool valve guide 37 and the cylinder block 7 are in contact with each other on the surfaces facing each other (the contact surface 37c and the input side end surface 7a), and the output side spool valve guide 47 and the cylinder block 7 are facing each other. Since the abutting surfaces (the abutting surface 47c and the output side end surface 7b) and the mutually facing surfaces are orthogonal to the axis of the input shaft 2, it is easy to input the spool valve by machining the facing surfaces with high accuracy. It is possible to ensure the accuracy of the axial reciprocation of 9, 9... And the output-side spool valves 11, 11..., Making parts easy to manufacture and contributing to reduction in manufacturing costs.

Further, the part where the input side spool valve guide 37 which is one spool valve guide and the bearing member (in this embodiment, the input side bearing housing 4) which supports the input shaft 2 are in contact with each other, or the other spool. A portion where the output-side spool valve guide 47, which is a valve guide, and a member that rotates integrally with the output shaft 13 (in this embodiment, the output-side swash plate 12) abuts is orthogonal to the axis of the input shaft 2. Since the concave portions 37a and 37a and the convex portions 4c and 4c, or the concave portions 47a and 47a and the convex portions 12c and 12c, which are engaged with each other on the inclined surface, are formed, the input side spool valve guide 37 and the output side The spool valve guide 47 is applied with a force in a direction in which the spool valve guide 47 abuts toward the input side end surface 7a and the output side end surface 7b of the cylinder block 7, respectively.
Therefore, the surfaces (contact surface 37c, contact surface 47c, input side end surface 7a, output side end surface 7b) on which the input side spool valve guide 37 and the output side spool valve guide 47 abut against the cylinder block 7 are processed with high accuracy. This makes it easy to ensure the accuracy of the reciprocating motion in the axial direction of the input-side spool valves 9, 9... And the output-side spool valves 11, 11. Contributes to reducing manufacturing costs.

Hereinafter, the detailed configuration of the link arm mechanism 60 for changing the inclination angle of the input-side swash plate 6 of the hydraulic continuously variable transmission 1 will be described with reference to FIGS. 1, 14, 15, 16, 17, and 18. FIG. To do.
In the case of the hydraulic continuously variable transmission 1 of the present embodiment, the speed change operation (the operation of changing the ratio of the rotational speed of the output shaft 13 to the rotational speed of the input shaft 2) changes the inclination angle of the input side swash plate 6. However, the inclination angle of the input side swash plate 6 is changed by the link arm mechanism 60.

  The link arm mechanism 60 mainly includes a first arm engagement member 61, a second arm engagement member 62, a link arm 63, a piston 64, a first engagement pin 65, a second engagement pin 66, an actuator 67, and the like. Is done.

The link arm 63 is a substantially L-shaped member in a side view, and a turning shaft 63a projects from a bent portion thereof. The turning shaft 63a is pivotally attached to the transmission housing case 24 and the like. . At this time, the axis center 69 of the rotation shaft 63a and the axis line of the virtual rotation center 68 of the input side swash plate 6 rotating in contact with the swash plate holding member 5 are substantially coincident (strictly speaking, As shown in FIGS. 17 and 18, there may be a slight deviation).
An engagement groove 63b is formed in an end portion of the link arm 63 having a smaller distance from the rotation shaft 63a, and the second arm engagement member 62 is slidable while being engaged with the engagement groove 63b. It is. At this time, since the engagement groove 63b is formed along a straight line connecting the rotation shaft 63a and the end portion having a smaller distance from the rotation shaft 63a, the second arm engagement member 62 is formed. The distance between the rotary shaft 63a and the rotary shaft 63a is variable.

  The second arm engagement member 62 is a substantially rectangular parallelepiped member, and a through hole is provided at the center thereof. A second engagement pin 66 that is a protruding member provided on one holding portion 6 b of the input side swash plate 6 is inserted into the through hole.

On the other hand, a first engagement pin 65 protrudes from the end of the link arm 63 that has a greater distance from the rotation shaft 63 a, and the first engagement pin 65 can rotate around the first arm engagement member 61. It is inserted in.
The first arm engaging member 61 is a member having substantially the same shape as the second arm engaging member 62, engages with the notch groove 64a of the piston 64, and can slide in the longitudinal direction of the notch groove 64a. is there.

  The piston 64 is a substantially cylindrical member, and is accommodated in a housing (not shown) so as to be slidable in the axial direction of the input shaft 2. A notch groove 64a is formed in the outer peripheral surface of the piston 64, and the longitudinal direction of the notch groove 64a is substantially orthogonal to the reciprocating direction of the piston 64 (the axial direction of the input shaft 2).

  The actuator 67 reciprocates the piston 64, and more specifically, a hydraulic motor, a hydraulic cylinder, an electric motor, an air cylinder, or the like.

  When the piston 64 reciprocates by the operation of the actuator 67, the link arm 63 engaged with the outer peripheral surface of the piston 64 via the first arm engagement member 61 and the first engagement pin 65 causes the rotation shaft 63a to move. Rotates as the center. Then, the input-side swash plate 6 engaged with the link arm 63 via the second arm engaging member 62 and the second engaging pin 66 rotates, and the inclination angle thereof changes.

The holding portions 6b and 6b of the input side swash plate 6 are members serving as a rotation center for changing the inclination angle of the swash plate surface 6a of the input side swash plate 6 as the input side swash plate 6 rotates. , And the input side plungers 8,... Are members that carry the load in the axial direction of the input shaft 2 acting on the input side swash plate 6. The holding portions 6b and 6b are substantially semi-cylindrical, and the input side swash plate 6 is held by the swash plate holding member 5 and can be rotated via the link arm 63.
However, with such a configuration, the rotation center of the virtual swash plate of the holding portions 6b and 6b needs to coincide with the center 69 of the rotation shaft 63a of the link arm 63, and strict assembly accuracy is required. The Rukoto.
Therefore, if the distance between the second arm engaging member 62 and the rotation shaft 63a is made variable, the following effects can be obtained, so that the virtual swash plate of the holding portions 6b and 6b can be obtained. A slight deviation between the rotation center and the center 69 of the rotation shaft 63a of the link arm 63 can be allowed.

As shown in FIG. 17, when the virtual rotation center 68 of the holding portions 6b and 6b of the input side swash plate 6 does not coincide with the axis center 69 of the rotation shaft 63a of the link arm 63, the input side swash plate. When 6 rotates, the shaft center 66a of the second engagement pin 66 projecting from the holding portions 6b and 6b moves on an arc-shaped locus 68a centering on the rotation center 68.
On the other hand, an arcuate locus 69a centering on the shaft center 69 of the rotation shaft 63a assumes that the link arm 63 rotates without changing the distance between the second engagement pin 66 and the rotation shaft 63a. Is a locus through which the axial center 66a of the second engagement pin 66 passes.

As shown in FIG. 17, when the virtual rotation center 68 of the holding portions 6b and 6b of the input-side swash plate 6 and the axis center 69 of the rotation shaft 63a of the link arm 63 do not coincide with each other, the locus 68a and the locus 69a does not match.
In such a case, if the distance between the second engagement pin 66 and the rotation shaft 63a is fixed, the portion where the input swash plate 6 and the swash plate holding member 5 are in contact (holding) There arises a problem that the portion 6b and the swash plate metal bearing 27) float or abut against each other excessively.

  However, when the second arm engaging member 62 is slidable in the engaging groove 63b provided at one end of the link arm 63 as in this embodiment, as shown in FIG. Since the locus | trajectory 68a and the locus | trajectory 69a correspond because 62 slides along the engaging groove 63b, generation | occurrence | production of the above problems can be prevented.

In addition, it is difficult to completely match the virtual rotation center 68 of the holding portions 6b and 6b of the input side swash plate 6 and the axis center 69 of the rotation shaft 63a of the link arm 63 during the assembly work. By constructing like the link arm mechanism 60 of the present embodiment, some assembling errors are allowed, so that workability at the time of assembling is improved.
Furthermore, the distance (variable) between the rotation shaft 63a of the link arm 63 and the second engagement pin 66 is shorter than the distance (fixation) between the rotation shaft 63a of the link arm 63 and the first engagement pin 65. By the lever principle, the force for reciprocating the piston 64 can be increased by the link arm 63 and converted to a force for rotating the input side swash plate 6 (swash plate tilting torque). Accordingly, the driving force of the piston 64 for rotating the input side swash plate 6 can be reduced.

In the present embodiment, the link arm 63 is substantially L-shaped when viewed from the side, but is not limited thereto, and may be a straight line or a “<” shape.
In other words, the link arm 63 may be a member having a first arm and a second arm with the shaft center 69 of the rotation shaft 63a as a fulcrum.

Hereinafter, the detailed configuration of the hydraulic continuously variable transmission 101 which is the second embodiment of the hydraulic apparatus of the present invention will be described with reference to FIGS. 19, 20, 21 and 22. The hydraulic continuously variable transmission 101 according to the present embodiment is used for shifting the driving force of a working vehicle (such as a tractor), but is not limited thereto, and various industries such as industrial machines and vehicles. Widely available in the field.
Further, members having substantially the same configuration and the same function as those of the hydraulic continuously variable transmission 1 which is the first embodiment of the hydraulic device of the present invention are given the same member numbers, and the first embodiment of the hydraulic device of the present invention is applied. Differences from the hydraulic continuously variable transmission 1 as an example will be described in detail.

  The difference between the hydraulic continuously variable transmission 101 and the hydraulic continuously variable transmission 1 is that the input side spool valves 9, 9... And the output side spool valves 11, 11. It is the structure of the input side spool valve guide and output side spool valve guide to reciprocate.

Hereinafter, the input side spool valve guide 137 and the output side spool valve guide 147, which are spool valve guides in the second embodiment of the hydraulic apparatus of the present invention, will be described in detail with reference to FIGS. 19, 20, 21, and 22. Do.
In this embodiment, the input-side spool valve guide 137 and the output-side spool valve guide 147 have the same shape for sharing parts, but the present invention is not limited to this, and the input-side spool valve guide 137 and the output-side spool valve guide 147 are not limited thereto. The guide 147 may have a different shape.

The input-side spool valve guide 137 is formed by subjecting the outer peripheral surface and inner peripheral surface of a substantially cylindrical member to various machining processes. The input-side spool valve guide 137 cooperates with the rotation of the input shaft 2 (cylinder block 7). 9 is reciprocated. The input-side spool valve guide 137 is loosely fitted to the input shaft 2 and also has a rear end portion of the body portion 4b of the input-side bearing housing 4 that is a bearing member that supports the input shaft 2 that is the first rotation shaft. The cylinder block 7 is interposed between the input side end face 7a. On the surface where the input side spool valve guide 137 and the input side bearing housing 4 abut, the input side spool valve guide 137 is formed with recesses 137a and 137a, and the rear end surface of the body portion 4b is formed with protrusions 4c and 4c. . The input side spool valve guide 137 cannot be rotated relative to the input shaft 2 by engaging the concave portions 137a and 137a with the convex portions 4c and 4c. Further, the convex portions 4c and 4c and the concave portions 137a and 137a have a substantially trapezoidal shape, and have surfaces that are inclined with respect to the axis of the input shaft 2 (not parallel to the surface perpendicular to the axis of the input shaft 2). Yes.
When the input-side spool valve guide 137 tries to rotate as the input shaft 2 and the cylinder block 7 rotate, the surfaces that are inclined with respect to the axis of the input shaft 2 of the convex portions 4c and 4c and the concave portions 137a and 137a contact each other. As a result, a force is generated to press the input side spool valve guide 137 in a direction in which the input side spool valve guide 137 contacts the input side end surface 7 a of the cylinder block 7.
Therefore, when the hydraulic continuously variable transmission 101 is in operation (when the input shaft 2 is rotated), the input side spool valve guide 137 can be prevented from rotating with the cylinder block 7 and the input side spool valve guide 137 is always in contact. Since it is pressed against the input side end face 7a of the cylinder block 7, the distance between the guide groove 137b formed in the input side spool valve guide 137 and the input side end face 7a is accurately maintained.
Even if a convex portion is formed on the input side spool valve guide 137 and a concave portion is formed on the bearing housing 4, substantially the same effect can be obtained.

  A guide groove 137 b is formed in a ring shape on the outer peripheral surface of the input side spool valve guide 137. An imaginary plane passing through the guide groove 137b is not orthogonal to the axis of the input side spool valve guide 137 (substantially coincides with the axis of the input shaft 2) and is inclined. Therefore, the distance between the guide groove 137 b and the contact surface 137 c that is a surface that contacts the cylinder block 7 varies depending on the position on the outer peripheral surface of the input side spool valve guide 137. The contact surface 137 c is orthogonal to the axis of the input shaft 2. The engaging portions 9d, 9d,... Of the input side spool valves 9, 9,.

A hydraulic oil groove 137 d is formed in the circumferential direction on the inner peripheral surface of the input side spool valve guide 137, and the hydraulic oil accumulated in the hydraulic oil groove 137 d is contacted between the contact surface 137 c and the input side end surface 7 a of the cylinder block 7. Supply grooves 137e, 137e,... For supplying and lubricating the contact parts are provided.
Further, hydraulic oil holes 137f and 137f communicating with the hydraulic oil groove 137d and the guide groove 137b are formed, and the hydraulic oil accumulated in the hydraulic oil groove 137d by the hydraulic oil holes 137f and 137f is guided to the guide groove 137b and the input side spool. The abutting parts of the valves 9, 9... Are lubricated to prevent wear and maintain the dimensional accuracy of each member.

  When the input shaft 2 makes one rotation with respect to the input side bearing housing 4 fixed to the transmission housing case 24, the cylinder block 7 also makes one rotation with respect to the input side bearing housing 4. Therefore, the input-side spool valves 9, 9... Engaged with the guide groove 137b make a round along the outer periphery of the input-side spool valve guide 137 along the guide groove 137b. At this time, the imaginary plane formed by the guide groove 137b is not parallel to the plane orthogonal to the axis of the input shaft 2 but is inclined, so that the input side spool valves 9, 9. Will reciprocate once.

A part of the input side spool valve guide 137 that requires particularly high dimensional accuracy (or flatness) in order to maintain the accuracy of the reciprocating motion (projection amount) of the input side spool valves 9, 9. .. Only the guide groove 37b with which the abutment surface 137c that abuts the input side end surface 7a and the engagement portions 9d, 9d... Contribute.
Since the number of members related to the reciprocation accuracy can be reduced, it is possible to reduce the accumulation of machining errors of each member (that is, improve the reciprocation accuracy).

The output-side spool valve guide 147 is formed by performing various machining on the outer peripheral surface and inner peripheral surface of a substantially cylindrical member, and is used for relative rotation between the input shaft 2 (cylinder block 7) and the output shaft 13. The output side spool valves 11, 11... The output-side spool valve guide 147 is a member that is loosely fitted to the front end portion of the outer peripheral surface of the spacer 50 that rotates integrally with the input shaft 2 and rotates integrally with the output shaft 13 that is the second rotation shaft. It is interposed between the contact surface 12 b formed at the front end of the output side swash plate 12 and the output side end surface 7 b of the cylinder block 7. On the surface where the output side spool valve guide 147 and the output side swash plate 12 abut, the output side spool valve guide 147 has recesses 147a and 147a, and the abutment surface 12b formed at the front end of the output side swash plate 12 Protrusions 12c and 12c are formed. When the concave portions 147a and 147a are engaged with the convex portions 12c and 12c, the output side spool valve guide 147 cannot rotate relative to the output side swash plate 12, and rotates integrally with the output side swash plate 12. . Further, the convex portions 12c and 12c and the concave portions 147a and 147a have a substantially trapezoidal shape, and have surfaces that are inclined with respect to the axis of the input shaft 2 (not parallel to the surface orthogonal to the axis of the input shaft 2). Yes.
When the output-side spool valve guide 147 tries to rotate relative to the output-side swash plate 12 as the input shaft 2 and the cylinder block 7 rotate, the convex portions 12c and 12c and the concave portions 147a and 147a have the input shaft 2 Due to the contact between the surfaces inclined with respect to the axis, a force is generated to press the output-side spool valve guide 147 in a direction to contact the output-side end surface 7 b of the cylinder block 7.
Therefore, when the hydraulic continuously variable transmission 101 is operated (when the input shaft 2 and the output shaft 13 are rotated), the output-side spool valve guide 147 can be prevented from rotating with the cylinder block 7 and the output-side spool. Since the valve guide 147 is always pressed against the output side end surface 7b of the cylinder block 7, the distance between the guide groove 147b formed in the output side spool valve guide 147 and the output side end surface 7b is accurately maintained.
Even if a convex portion is formed on the output-side spool valve guide 147 and a concave portion is formed on the output-side swash plate 12, substantially the same effect can be obtained.

  A guide groove 147 b is formed in a ring shape on the outer peripheral surface of the output side spool valve guide 147. A virtual plane passing through the guide groove 147b is not orthogonal to the axis of the output-side spool valve guide 147 (substantially coincides with the axis of the input shaft 2) and is inclined. Therefore, the distance between the guide groove 147 b and the contact surface 147 c that is a surface that contacts the cylinder block 7 varies depending on the position of the output-side spool valve guide 147 on the outer peripheral surface. The contact surface 147 c is orthogonal to the axis of the input shaft 2. The engaging portions 11d, 11d,... Of the output side spool valves 11, 11,.

A hydraulic oil groove 147d is formed in the circumferential direction on the inner peripheral surface of the output-side spool valve guide 147. The hydraulic oil accumulated in the hydraulic oil groove 147d is contacted between the contact surface 147c and the output-side end surface 7b of the cylinder block 7. Supply grooves 147e, 147e,... For supplying and lubricating the contact parts are provided.
Further, hydraulic oil holes 147f and 147f communicating with the hydraulic oil groove 147d and the guide groove 147b are formed, and the hydraulic oil accumulated in the hydraulic oil groove 147d by the hydraulic oil holes 147f and 147f is guided to the guide groove 147b and the output side spool. The abutting part of the valves 11, 11... Is lubricated.

  When the output shaft 13 makes one rotation relative to the input shaft 2, the output shaft 13 also makes one rotation relative to the cylinder block 7. Therefore, the output-side spool valves 11, 11... Engaged with the guide groove 147b make one round along the guide groove 147b on the outer peripheral surface of the output-side spool valve guide 147 that cannot rotate relative to the output shaft 13. To do. At this time, the imaginary plane formed by the guide groove 147b is not parallel to the plane orthogonal to the axis of the input shaft 2, but is inclined, so that the output side spool valves 11, 11,. Will reciprocate once.

A portion of the output side spool valve guide 147 that requires particularly high dimensional accuracy (or flatness) in order to maintain the accuracy of the reciprocating motion (protrusion amount) of the output side spool valves 11. 7 is only the guide groove 147b with which the abutment surface 147c that abuts on the output side end surface 7b and the engagement portions 11d, 11d,... Contribute.
Since the number of members related to the reciprocation accuracy can be reduced, it is possible to reduce the accumulation of machining errors of each member (that is, improve the reciprocation accuracy).

  As described above, the hydraulic continuously variable transmission 101 which is the second embodiment of the hydraulic apparatus of the present invention includes the input shaft 2 as the first rotating shaft and the output shaft 13 as the second rotating shaft, and the axial direction. The input side plungers 8, 8... Which are the first plungers reciprocally moving and the output side plungers 10.10. The input side spool valves 9, 9 ... and the output side spool valves 11, 11 ..., which are the second spool valves, and the input side plungers 8, 8 ..., the output side plungers 10, 10, ... The cylinder block 7 that accommodates the input-side spool valves 9, 9... And the output-side spool valves 11, 11,. Input side plunger on plate surface 6a The input side swash plate 6, which is the first swash plate that contacts 8 ..., and the output side plunger 10, 10 ... on the swash plate surface 12a that forms a predetermined inclination angle with respect to the axis. The output side swash plate 12 that is a second swash plate that rotates integrally with the output shaft 13, and the input side plunger holes 31, 31. Is formed in the cylinder block 7 to communicate with the output side plunger holes 41, 41..., Which is a hole for receiving the plunger, and the input side plungers 8, 8. ·········································· Switches the flow path of the hydraulic oil entering and exiting the input side plunger holes 31. To the side plunger holes 41 The operation oil flow path is switched, and an input side spool valve guide 137 provided with a guide groove 137b displaced in the axial direction and an output side provided with a guide groove 147b similarly displaced in the axial direction. The input side spool valves 9, 9... Engage with the guide grooves 137b, and the output side spool valves 11, 11. Are required to have high dimensional accuracy in order to maintain the accuracy of the reciprocating movement in the axial direction of the input side spool valves 9, 9... And the output side spool valves 11, 11. In the example, it is possible to reduce the number of parts of the input side spool valve guide 137, the output side spool valve guide 147, and the cylinder block 7), thereby reducing the manufacturing cost. Is possible.

  Further, the input side spool valve guide 137 and the cylinder block 7 are in contact with each other on the surfaces facing each other (the contact surface 137c and the input side end surface 7a), and the output side spool valve guide 147 and the cylinder block 7 are facing each other. Since the abutting surfaces (the abutting surface 147c and the output side end surface 7b) and the mutually facing surfaces are orthogonal to the axis of the input shaft 2, the facing spool valve can be easily obtained by machining the facing surfaces with high accuracy. It is possible to ensure the accuracy of axial reciprocation of the 9 · 9... And the output side spool valves 11 · 11... .

Furthermore, the part where the input side spool valve guide 137 which is one spool valve guide and the bearing member (in this embodiment, the input side bearing housing 4) which supports the input shaft 2 abut or the other spool. A portion where the output side spool valve guide 147 that is a valve guide and a member that rotates integrally with the output shaft 13 (in the present embodiment, the output side swash plate 12) abuts is orthogonal to the axis of the input shaft 2. Since the concave portions 137a and 137a and the convex portions 4c and 4c, or the concave portions 147a and 147a and the convex portions 12c and 12c, which are engaged with each other on the inclined surface, are formed, the input side spool valve guide 137 and the output side The spool valve guide 147 is applied with a force in a direction of abutting toward the input side end surface 7a and the output side end surface 7b of the cylinder block 7, respectively.
Therefore, the surfaces (contact surface 137c, contact surface 147c, input side end surface 7a, output side end surface 7b) with which the input side spool valve guide 137 and the output side spool valve guide 147 contact the cylinder block 7 are processed with high accuracy. This makes it easy to ensure the accuracy of the reciprocating motion in the axial direction of the input-side spool valves 9, 9... And the output-side spool valves 11, 11. Excellent and contributes to reducing manufacturing costs.

  The input-side spool valve guide 137 and the output-side spool valve guide 147, which are spool valve guides in the second embodiment of the hydraulic apparatus of the present invention, are inputs that are spool valve guides in the first embodiment of the hydraulic apparatus of the present invention. Unlike the side spool valve guide 37 and the output side spool valve guide 47, the engaging portions 9d, 9d,... Of the input side spool valves 9, 9 ... are directly engaged with the guide groove 137b and output to the guide groove 147b. Since the engaging portions 11d, 11d,... Of the side spool valves 11, 11... Are directly engaged, the input side holding member 38 and the input on the input side spool valve guide 37 and the output side spool valve guide 47, Parts such as the side holding member presser 39, the output side holding member 48, and the output side holding member presser 49 can be omitted, and the manufacturing cost can be further reduced. Contribute to.

  In the present embodiment, the guide groove 137b and the guide groove 147b are configured to ride on a virtual plane inclined with respect to the input shaft 2, but are not limited thereto. For example, when the spool valve is moving from the bottom dead center to the top dead center, the first half is a groove having a large axial displacement and the second half is a groove having a small axial displacement, and when the spool valve is moving from the top dead center to the bottom dead center, the first half is an axis. A groove having a small displacement in the direction and a large displacement in the axial direction may be used in the latter half. The shape of such a groove can be appropriately selected according to the drive characteristics of the hydraulic device.

In this embodiment, the first rotating shaft is used as the input shaft 2 and the second rotating shaft is used as the output shaft 13. However, the present invention is not limited to this, and the first rotating shaft is used as the output shaft and the second rotating shaft is used. An axis may be used as the input axis.
In this case, the relationship between the rotation speed Nout of the first rotation shaft as the output shaft and the rotation speed Nin of the second rotation shaft as the input shaft replaces Nout and Nin in (Equation 4). It is organized as a thing. That is, Nout = Nin × Vin / (Vin + Vout). Here, Vin is the stroke volume of the plunger that is in contact with the fixed swash plate, Vin is constant, and the stroke volume Vout of the plunger that is in contact with the variable swash plate is −Vin ≦ If it is varied in the range of Vout ≦ Vin, theoretically, (1/2) × Nin ≦ Nout <+ ∞.

The side sectional view concerning the 1st example of a hydraulic device. 1 is a side sectional view of a cylinder block according to a first embodiment of a hydraulic device. The front view of a cylinder block. The perspective view of a spool valve. The perspective view of the spool valve guide which concerns on 1st Example of a hydraulic device. The perspective view of the holding member which concerns on the 1st Example of a hydraulic device. The perspective view of an output side swash plate. The principal part side view which concerns on 1st Example of a hydraulic device. The schematic diagram which shows the flow of the hydraulic fluid in the hydraulic closed circuit at the time of speed increasing operation. The schematic diagram which shows the flow of the hydraulic fluid in the hydraulic closed circuit at the time of deceleration operation. FIG. 3 is a developed schematic view of a cylinder block. The schematic diagram which shows the hydraulic closed circuit of the hydraulic apparatus of this invention. The figure which shows the relationship between the stroke volume of the input side hydraulic apparatus in the hydraulic apparatus of this invention, and the rotation speed of an output shaft. The side view of a link arm. The plane partial sectional view of a link arm. The plane schematic diagram which shows a link arm mechanism. The figure which shows the positional relationship of the link arm and input side swash plate before rotation. The figure which shows the positional relationship of the link arm after rotation, and the input side swash plate. Side surface sectional drawing which concerns on 2nd Example of a hydraulic apparatus. Side surface sectional drawing of the cylinder block which concerns on 2nd Example of a hydraulic device. The perspective view of the spool valve guide which concerns on 2nd Example of a hydraulic device. The principal part side view which concerns on 2nd Example of a hydraulic device.

Explanation of symbols

1 Hydraulic continuously variable transmission (hydraulic device)
2 Input shaft (first rotary shaft)
6 Input side swash plate (first swash plate)
7 Cylinder block 8 Input side plunger (first plunger)
9 Input side spool valve (first spool valve)
10 Output side plunger (second plunger)
11 Output side spool valve (second spool valve)
12 Output side swash plate (second swash plate)
13 Output shaft (second rotary shaft)
37 Input side spool valve guide (Spool valve guide)
38 Input side holding member (holding member)
47 Output side spool valve guide (Spool valve guide)
48 Output side holding member (holding member)

Claims (1)

In the hydraulic device, the angle formed between the swash plate surface of the swash plate and the axis of the cylinder block can be changed by rotating the swash plate via a link arm that is rotatably provided.
A hydraulic apparatus, wherein a protruding member provided on a swash plate is fitted on an engaging member, and the engaging member is slidably fitted in an engaging groove provided on one end of a link arm.

Images