JP2003014079A - Hydraulic continuously variable transmission and power transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic continuously variable transmission and a power transmission simplifying the reciprocating structure of a distributing valve. SOLUTION: A flange face of a flange 72 of a retainer 70 rotatable synchronously with a cylinder block 42 is inclined with respect to the axis O of a cylinder block, and a constricted part 66b of a selector valve 66 is engaged with a lock groove 73 formed in the flange 72. This engaged relation allows the selector valve 66 to reciprocate following the rotation of the cylinder block 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic continuously variable transmission and a power transmission device which can be widely used in various industrial fields such as industrial machines and vehicles.

[0002]

2. Description of the Related Art Conventionally, a hydraulic pressure provided with a first hydraulic device for discharging and sucking hydraulic oil by reciprocating motions of a plurality of plungers and a second hydraulic device having an output rotating portion for obtaining output rotation by abutting of a plurality of plungers. Type continuously variable transmissions are known. The first and second hydraulic devices of such a hydraulic continuously variable transmission share a cylinder block, and the cylinder block is configured to rotate around its axis.

In the cylinder block, hydraulic oil circulates between a plurality of plunger chambers for accommodating the plungers of the first hydraulic device and a plurality of plunger chambers for accommodating the plungers of the second hydraulic device. A hydraulic closed circuit is provided. The hydraulic oil circulates between the plunger chambers due to the reciprocating movement of the plurality of distribution valves provided in the cylinder block.

In such a hydraulic continuously variable transmission,
Conventionally, in order to give a reciprocating motion to each distribution valve in the axial direction, each distribution valve is arranged parallel to the axis of the cylinder block, and the tip of the distribution valve is brought into contact with the swash plate.

[0005]

By the way, in the above-mentioned conventional technique, the tip end of the distribution valve is brought into contact with the swash plate, so that the distribution valve reciprocates in the axial direction while making one revolution around the axis of the cylinder block. It is configured to do. However, with such a structure, a spring or the like for pressing the distribution valve from the side opposite to the swash plate toward the swash plate is required.

Further, in the above-mentioned conventional technique, since the tip end of the distribution valve is brought into contact with the swash plate to give reciprocating motion to the distribution valve, the distribution valve and the swash plate are rotated while the cylinder block is rotating. In between, there was a problem that an unbalanced state, which is relatively difficult to improve due to design in the axial direction of the cylinder block, occurs. For this reason, it has been required to reciprocate the distribution valve in the axial direction other than contacting the tip of the distribution valve with the swash plate.

The present invention has been made in view of the above circumstances, and a first object thereof is to provide a hydraulic continuously variable transmission and a power transmission device which can simplify the reciprocating structure of a distribution valve. It is in. A second object is to provide a hydraulic continuously variable transmission and a power transmission device that can easily eliminate the unbalanced state when the distribution valve reciprocates.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 provides output by contact between a first hydraulic device for discharging and sucking hydraulic oil by reciprocating motion of the plunger and the plunger. A cylinder block of the second hydraulic device having an output rotating portion for obtaining rotation is shared, and the cylinder block is configured to rotate around its axis, and the plunger chamber of the first hydraulic device and the plunger chamber of the second hydraulic device are shared. A hydraulic continuously variable transmission in which a hydraulic closed circuit in which hydraulic fluid circulates between the cylinder blocks is provided and the hydraulic fluid is circulated between the plunger chambers by the reciprocating movement of the distribution valve provided in the cylinder block. Is arranged parallel to the axis of the cylinder block, the distribution valve is tilted in the direction of the axis of the cylinder block, and rotates in synchronization with the cylinder block. And summarized in that where the structure engages with the reciprocating imparting member for imparting reciprocating the valve.

According to a second aspect of the invention, there is provided a power transmission device using the hydraulic continuously variable transmission according to the first aspect,
The cylinder block is configured to rotate by the input shaft from the prime mover, the input shaft is extended to the side opposite to the prime mover, and the output rotating part is provided on the outer periphery of the extended input shaft. The present invention is characterized in that a forward / reverse rotation switching device for transmitting power by reversing or reversing is provided, and a connecting / disconnecting means for turning on / off rotation transmission to / from a rotating shaft of a prime mover is provided.

According to the third aspect of the present invention, the cylinder block of the second hydraulic system having the first hydraulic system for discharging and sucking hydraulic oil by the reciprocating motion of the plunger and the output rotary section for obtaining the output rotation by the contact of the plunger. The cylinder block is configured to rotate about its axis, and a closed hydraulic circuit is provided in the cylinder block, in which hydraulic oil circulates between the plunger chamber of the first hydraulic device and the plunger chamber of the second hydraulic device. In a hydraulic continuously variable transmission configured such that hydraulic oil circulates between the plunger chambers by the reciprocating movement of the distribution valve provided in the cylinder block, the distribution valve is arranged parallel to the cylinder block axis, and the tip of the distribution valve is It comes into contact with a slanted surface, and the slanted surface is arranged symmetrically with respect to its own axis so that the coaxial line is displaced from the cylinder block axis line and the same as the cylinder block. And summarized in that formed in the reciprocating applying member to rotate.

According to a fourth aspect of the present invention, there is provided a power transmission device using the hydraulic continuously variable transmission according to the third aspect,
The cylinder block is configured to rotate by the input shaft from the prime mover, the input shaft is extended to the side opposite to the prime mover, and the output rotating part is provided on the outer periphery of the extended input shaft. The present invention is characterized in that a forward / reverse rotation switching device for transmitting power by reversing or reversing is provided, and a connecting / disconnecting means for turning on / off rotation transmission to / from a rotating shaft of a prime mover is provided.

(Operation) According to the invention of claim 1, the distribution valve is arranged so as to be inclined in the axial direction of the cylinder block, and is engaged with the reciprocating motion imparting member which rotates in synchronization with the cylinder block. The reciprocating motion imparting member imparts reciprocating motion to the distribution valve.

According to the invention of claim 2, the operation of the invention of claim 1 can be obtained also in the power transmission device. According to the invention of claim 3, the distribution valve is arranged symmetrically with respect to its own axis, and the coaxial line is arranged so as to be displaced from the cylinder block axis, and abuts on the slope of the reciprocating motion imparting member that rotates in synchronization with the cylinder block. To be done. The reciprocating motion imparting member imparts reciprocating motion to the distribution valve.

According to the invention of claim 4, the operation of the invention of claim 3 can be obtained also in the power transmission device.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Hereinafter, a hydraulic type continuously variable transmission (hereinafter referred to as continuously variable transmission) 20 which is used as a working machine for traveling of a working vehicle according to the present invention, An embodiment embodied in a power transmission device including a continuously variable transmission device 20 will be described with reference to FIGS. 1 to 12.

As shown in FIGS. 1 and 3, the continuously variable transmission 2
0 is stored in the case 26 of the power unit of the working vehicle. The continuously variable transmission 20 is the first hydraulic device 10.
0, and a second hydraulic device 200 that forms a hydraulic closed circuit C (see FIGS. 9 and 10) between the first hydraulic device 100 and the first hydraulic device 100.

FIG. 8 is a conceptual diagram showing a power transmission device including a continuously variable transmission 20. Input shaft 21 of continuously variable transmission 20
Is connected to the crank shaft of the engine 22 via the clutch mechanism 300, and is connected to the output side yoke 23, which will be described later.
The gear shift device 138 (CST) is connected. The clutch mechanism 300 is adapted to engage and disengage in conjunction with a foot-operated clutch pedal (not shown).

The gear shift device 138 includes the first clutch 1
39 and a second clutch 140. When the driven clutch plate is connected to the drive side clutch plate connected to the yoke 23, the first clutch 139 causes the gear 141 connected to the driven clutch plate to move to the gear 14
The drive torque is transmitted to the final reduction gear transmission (not shown) via 2. When the driven clutch plate is connected to the drive side clutch plate connected to the yoke 23, the second clutch 140 has a gear 143, an idler gear 144,
145 and the gear 14 meshed with the idler gear 145
The drive torque is transmitted to the final reduction gear transmission (not shown) via 2.

The gear shift device 138 includes the shift lever 14
6 (see FIG. 11), and based on the operation of this shift lever 146, the first clutch 13
9 is connected, and the second clutch 140 is connected during reverse travel.

In the present embodiment, the engine 22
Is a motor, the clutch mechanism 300 is a connecting / disconnecting device, and the gear shift device 138 is a forward / reverse rotation switching device. The case 26 of the continuously variable transmission 20 includes a cylindrical tubular member 27.
And a pair of side wall members 30 and 31 integrally connected by bolts (not shown) through bolt insertion holes 28 and 29 (see FIG. 1) so as to close the openings at both ends of the tubular member 27. There is.

In the input shaft 21 of the continuously variable transmission 20,
The input end side is rotatably supported by the side wall member 30 of the case 26 via a bearing 32. Also, case 2
The side wall member 31 of 6 has a yoke 23 as an output rotating portion.
Are rotatably supported via bearings 33. Then, the output end side of the input shaft 21 is positioned coaxially with the yoke 23, so that the pair of bearings 23 a are provided with respect to the yoke 23.
And is rotatably pierced and supported via the seal 23b. The end protruding from the yoke 23 at the output end is P
It is the TO axis.

As shown in FIG. 4, at the center of the side wall member 30, a pair of bearing accommodating holes 34 and 35 are arranged side by side so as to be coaxially arranged on both inner and outer side surfaces. A through hole 36 having a diameter smaller than that of the bearing housing holes 34, 35 is formed between the bearing housing holes 34, 35. A sleeve 37 is rotatably arranged in the through hole 36, and conical roller bearings 38, 39 are symmetrically fitted and fixed in the bearing receiving holes 34, 35 with the through hole 36 interposed therebetween. The input shaft 21 is supported via both conical roller bearings 38 and 39. Further, the opening of the bearing housing hole 34 is covered with the cover 15 bolted to the side wall member 30. As shown in FIG. 4, the input shaft 21 is passed through the through hole 15 a of the cover 15 via the seal member 16.

The outer ring 38a of the conical roller bearing 38 is in contact with the bearing housing hole 34 through a shim 50. Further, the outer ring 39 a of the conical roller bearing 39 is fixed in contact with the step portion on the inner side of the bearing housing hole 35. In the bearing housing hole 34, a nut 40 is screwed onto the outer periphery of the input shaft 21 on the input end side. The inner ring 38b of the conical roller bearing 38 presses the inner ring 39b of the conical roller bearing 39 through the sleeve 37 by screwing the nut 40, and the input shaft 21
The sleeve 41 fitted to is pressed. The sleeve 41 presses the cylinder block 42. Then, the cylinder block 42 is brought into contact with a locking portion 46 provided on the outer circumference of the input shaft 21. Therefore, the cylinder block 42 can be fixed in the axial direction only by screwing the nut 40 from only the input end side. Further, by adjusting the number and thickness of the shims 50 interposed between the outer ring 38a and the side wall member 30, the bearing 3
It is possible to adjust the degree of close contact between the inner ring and the outer ring of each of 8, 39.

Conical roller bearings 38, 39 and sleeve 37
The bearing portion 32 is configured by the above. (First Hydraulic System 100) The first hydraulic system 100 includes an input shaft 21, a cylinder block 42, a plunger 43, and a cradle 45 including a swash plate surface 44 that abuts against the plunger 43. The input shaft 21 passes through the cradle 45.

As shown in FIG. 3, the cradle 45 is supported so as to be tiltable with respect to the case 26 about a trunnion axis TR that is orthogonal to the axis O of the cylinder block 42. That is, the cradle 45 has an upright position where a virtual plane including the swash plate surface 44 is orthogonal to the axis O. With reference to this upright position, the cradle 45 is tilted in the counterclockwise direction in FIG. 3 by a predetermined angle (first position) and in the upright position by a predetermined angle in the clockwise direction (reference position). The second position) is tiltable.

In the present embodiment, the clockwise direction is positive and the counterclockwise direction is negative in FIG. 3 with reference to when the swash plate surface 44 is located in the upright position. In the present embodiment, when the output speed Nout = Nin in FIG.
When out> Nin, tilts to the negative side, and when Nout <Nin,
Tilt to the positive side. The output rotation speed is the rotation speed of the yoke 23.

The swash plate surface 44 shown in FIG. 3 shows a state in which the cradle 45 is tilted at the maximum negative tilt angle position when the cradle 45 is located at the first position. Further, when the cradle 45 is located at the second position, the swash plate surface 44 is referred to as a positive maximum tilt angle position.

The cylinder block 42 is integrally connected to the input shaft 21 by spline 21a coupling. The cylinder block 42 has a substantially cylindrical combination shape, and both end circumferential surfaces located in the axial direction are smaller in diameter than the central portion.

In the cylinder block 42, as shown in FIG. 2, a plurality of plunger holes 47 are annularly arranged around the center of rotation (axis O) of the center portion of the cylinder block 42.
It is extended in parallel with. As shown in FIG. 3, the plunger hole 47 has an opening on the side of the cradle 45 on the step surface at the center of the cylinder block 42. The plunger 43 is slidably arranged in each plunger hole 47. The plunger hole 47 corresponds to the plunger chamber. A steel ball 48 is rotatably fitted to the tip of the plunger 43, and the plunger 43 is brought into contact with the swash plate surface 44 through the steel ball 48 and the shoe 49 to which the steel ball 48 is attached. There is. The swash plate surface 44 in the inclined state is the cylinder block 4
With the rotation of 2, the plunger 43 is reciprocally actuated to impart the action of the suction and discharge strokes. In addition, FIG. 3 is C of FIG.
FIG. 3 is a sectional view taken along line C, and FIG. 1 is a sectional view taken along line DD of FIG.

(Second hydraulic device 200) Second hydraulic device 20
Reference numeral 0 includes a plurality of plungers 58 slidably arranged on the cylinder block 42, and a cylindrical yoke 23 having a rotating inclined surface 51 that abuts on the plunger 58.

As shown in FIGS. 1 and 3, a bearing accommodating hole 52 and a through hole 53 having a diameter smaller than that of the bearing accommodating hole 52 are formed in the side wall member 31 so as to be coaxial with each other. The conical roller bearing 5 is placed in the bearing housing hole 52.
4 is fitted. A ball bearing 55 is fixed to the inner peripheral surface of the output end of the tubular member 27. The yoke 23 has a large-diameter portion and a small-diameter portion. The large-diameter portion is fitted to the ball bearing 55, and the small-diameter portion is fitted to the conical roller bearing 54, so that the yoke 23 is rotatably supported. Further, the small diameter portion of the yoke 23 is projected to the outside through a seal member 56 fixed in the through hole 53.

The rotary inclined surface 51 is formed on the end surface of the yoke 23 on the cylinder block 42 side, and a virtual plane including the rotary inclined surface 51 is inclined at a constant angle with respect to the axis O.

At the center of the cylinder block 42,
As shown in FIG. 2, the same number of plunger holes 57 as the plunger holes 47 are annularly arranged around the rotation center and extend parallel to the axis O. The plunger hole 57 corresponds to the plunger chamber. The pitch circle of the plunger hole 57 is concentric and has the same diameter as the pitch circle of the plunger hole 47. Further, as shown in FIG. 2, the plunger holes 57 are arranged so as to be located between the plunger holes 47 adjacent to each other in the circumferential direction of the cylinder block 42 so as to be offset from the plunger holes 47 by 1/2 pitch. There is.

The plunger hole 57 is formed in the cylinder block 42.
An opening is formed on the side of the yoke 23 on the step surface of the central portion of the. A plunger 58 is slidably arranged in each plunger hole 57, and a steel ball 59 is rotatably fitted to the tip of the plunger 58. Plunger 58 is steel ball 59
And the shoe 60 to which the steel ball 59 is attached is abutted on the rotating slope 51. The plunger 58 reciprocates according to the relative rotation between the rotary slope 51 and the cylinder block 42, and the suction and discharge strokes are repeated. In this embodiment,
The maximum stroke volume VPmax of the first hydraulic apparatus 100 is set to be the same as the maximum stroke volume VMmax of the second hydraulic apparatus 200.

(Hydraulic Closed Circuit C) Next, the hydraulic closed circuit C formed between the first hydraulic device 100 and the second hydraulic device 200 will be described.

An annular first oil chamber 61 and a second oil chamber 62 are arranged side by side in the axial direction of the cylinder block 42 on the inner peripheral surface of the cylinder block 42. For convenience of explanation, the first oil chamber 61 is referred to as the oil chamber A and the second oil chamber 6 is referred to.
2 may be referred to as an oil chamber B.

In the cylinder block 42, the same number of first valve holes 63 that connect the first oil chamber 61 and the second oil chamber 62 to each other are provided so as to extend parallel to the axis O of the cylinder block 42. There is. In addition, the cylinder block 42 has a second oil chamber 61 and a second oil chamber 62 that communicate with each other.
The same number of valve holes 64 as the plunger holes 57 extend parallel to the axis O of the cylinder block 42. The first valve hole 63 and the second valve hole 64 are annularly arranged around the axis O of the cylinder block 42.

The pitch circle of the first valve hole 63 is concentric and has the same diameter as the pitch circle of the second valve hole 64. Also, both valve holes 6
The diameters of the pitch circles 3 and 64 are smaller than the pitch circles of the plunger holes 47 and 57 so that they are located inward of the plunger holes 47 and 57. Further, as shown in FIG. 2, in the circumferential direction of the cylinder block 42, each first valve hole 63 is positioned between the adjacent second valve holes 64.
The second valve holes 64 are arranged so as to be offset from each other by ½ pitch. Then, as shown in FIG. 1, when the continuously variable transmission 20 is cut along the direction of the axis O, the first valve hole 63
The second valve hole 64 and the second valve hole 64 are positioned opposite to each other with the axis O interposed therebetween. Further, the centers of the first valve hole 63 and the plunger hole 47, and the centers of the second valve hole 64 and the plunger hole 57 are located on a straight line radially extending from the axis O in the radial direction as shown in FIG. Are arranged as follows.

As shown in FIG. 1, the oil passage 65 connects between the bottom portion of the plunger hole 47 and the portion between the first oil chamber 61 and the second oil chamber 62 of the first valve hole 63. Has been formed. A portion between the bottom of the plunger hole 47 and the first oil chamber 61 and the second oil chamber 62 of the first valve hole 63 has a predetermined distance in the length direction of the cylinder block 42 (direction in which the axis O extends). Are arranged to have. Therefore,
As shown in FIGS. 1 and 5, the oil passage 65 is inclined from the outer peripheral side of the cylinder block 42 toward the inside.

Each first valve hole 63 has a first oil chamber 61 and a second oil chamber 61.
A port U of the oil passage 65 communicating with the corresponding plunger hole 47 is formed between the oil chamber 62 and the oil chamber 62. Each first
A spool-type first switching valve 66 is slidably arranged in the valve hole 63. The first switching valve 66 corresponds to the distribution valve. Since the first switching valve 66 is arranged in the first valve hole 63, the first valve hole 63 is provided with respect to the cylinder block 42.
The arrangement is similar to the above. Therefore, the first switching valve 6
6 is arranged parallel to the axis O of the cylinder block 42.

As shown in FIGS. 1 and 4, a cylindrical holder 68 is fixed to the outer peripheral surface of the outer ring 39a of the conical roller bearing 39. On the inner peripheral surface of the holder 68, the axis O
The central portion in the direction is a reduced diameter portion 68b having a reduced diameter.
A retainer 70 as a reciprocating motion imparting member is rotatably supported by the reduced diameter portion 68b via a ball bearing 69.
As shown in FIG. 6A, the retainer 70 is composed of a cylindrical tubular portion 71 and a flange 72 that is formed to project from the end of the tubular portion 71 on the cylinder block 42 side. The ball bearing 69 allows the retainer 70 to rotate synchronously with the cylinder block 42.

Further, as shown in FIG. 4, the retainer 70 is arranged so that its axis is oblique to the axis O by the ball bearing 69, and in this state, the input shaft 21 is rotatably penetrated. ing. Due to this oblique intersection, the virtual plane including the surface of the flange 72 that faces the cylinder block 42 (hereinafter referred to as the flange surface) obliquely intersects the axis O.

As shown in FIG. 6 (b), a retaining groove 73 is formed in the flange 72 of the retainer 70 by cutting at an equal angle from the outer circumference toward the shaft center around the shaft center. As shown in FIG. 6B, a constricted portion 66b provided on the first switching valve 66 is engaged with the locking groove 73.
The constricted portion 66b has tapered surfaces 66d on both sides in the longitudinal direction.
The diameter is smaller than that of the large-diameter portion 66c adjacent to each other through. The taper surface 66d is formed so that the distance from the other taper surface 66d facing the taper surface 66d becomes shorter as it goes toward the axis of the first switching valve 66. Both side surfaces of the flange 72 are arranged so as to make line contact with the tapered surface 66d.

Accordingly, the first switching valve 66 reciprocates along the axial direction of the cylinder block 42 by engaging the retainer 70 having the flange surface obliquely intersecting the axis O.
A displacement as shown in FIG. 7 is realized.

The flange 72 of the retainer 70 is shown in FIG.
As shown in FIG. 1, the first switching valve 66 connects the port U with the second oil chamber 62 about the port closed position n0.
The opening position n1 and the second opening position n2 that connects the port U and the first oil chamber 61 are reciprocated. With this retainer 70, the first hydraulic device 100 has a region H in the range of 0 degrees to 180 degrees and 180 degrees to 360 (0) degrees corresponding to the rotational direction of the cylinder block 42 around the axis O. Region I is given within the range.

Here, the region H means the port U and the second oil chamber 6
2 is an area including all sections communicating with each other, and an area I
Is an area including the entire section in which the port U and the first oil chamber 61 communicate with each other.

When the swash plate surface 44 is displaced from the upright position to the maximum negative tilt angle position, the stroke volume VP of the first hydraulic system 100 at this time is 0 to VMm in FIG.
It becomes ax, and the input rotation speed of the input shaft 21 is Nin accordingly.
Output revolution speed Nout (revolution speed of the yoke 23) is Nin
In the present embodiment, the discharge amount of hydraulic oil on the side of the first hydraulic device 100 is set so as to obtain a speed in the range from 1 to 2 Nin.

In FIG. 12, the vertical axis represents the stroke volume per revolution of the first hydraulic device 100 or the second hydraulic device 200, and the horizontal axis represents the output rotational speed Nout of the yoke 23 (output rotating portion). There is. In the same figure, the solid line shows the change of the stroke volume VP of the first hydraulic device 100, and the chain line shows the change of the stroke volume VM of the second hydraulic device 200.

The stroke volume of the first hydraulic system 100 means that the plunger space formed by the plunger 43 and the plunger hole 47 is exchanged with the first oil chamber 61 and the second oil chamber 62 while the cylinder block 42 makes one rotation. It is the amount of hydraulic oil to be used. The stroke volume of the second hydraulic device 200 means the plunger 5
8 and the plunger hole 57, the amount of hydraulic oil that is exchanged with the first oil chamber 61 and the second oil chamber 62 while the yoke 23 (output rotating portion) makes one rotation with respect to the cylinder block 42. That is.

Further, in the present embodiment, when the swash plate surface 44 tilts to the negative side as shown in FIG.
The operating oil is sucked into the plunger hole 47 through the port U in the range of the rotation angle of 0 to 180 degrees around the axis O of
The hydraulic oil is discharged from the plunger hole 47 through the port U in the range of 0 to 360 (0) degrees. And swash plate surface 4
When 4 is tilted to the positive side, hydraulic oil is discharged from the plunger hole 47 through the port U within the range of the rotation angle of the cylinder block 42 around the axis O of 0 to 180 degrees, and 180 to 180 degrees.
The hydraulic oil is sucked into the plunger hole 47 through the port U in the range of 360 (0) degrees. The oil chamber to be discharged and the oil chamber to be sucked are determined by regions H and I corresponding to the rotation angle of the cylinder block 42 around the axis O.

As shown in FIGS. 1 and 3, the oil passage 75 is
The bottom of the plunger hole 57 and the first oil chamber 6 of the second valve hole 64.
The first and second oil chambers 62 are formed to communicate with each other. The bottom of the plunger hole 57 and the second valve hole 6
The portion between the first oil chamber 61 and the second oil chamber 62 is the length direction of the cylinder block 42 (the direction in which the axis O extends).
Are arranged so as to have a predetermined distance. Therefore, as shown in FIGS. 1 and 3, the oil passage 75 is inclined from the outer peripheral side of the cylinder block 42 toward the inner side.

Each second valve hole 64 has a first oil chamber 61 and a second oil chamber 61.
A port W of an oil passage 75 communicating with the corresponding plunger hole 57 is formed between the oil chamber 62 and the oil chamber 62. Each second
A second spool-type switching valve 76 is slidably arranged in the valve hole 64 so as to be parallel to the plunger 58. The second switching valve 76 corresponds to the distribution valve. Since the second switching valve 76 is arranged in the second valve hole 64, it has the same arrangement configuration as the second valve hole 64 with respect to the cylinder block 42. Therefore, the first switching valve 66 is arranged parallel to the axis O of the cylinder block 42.

As shown in FIGS. 1 and 5, a housing hole 78 is formed at the center of the end surface of the yoke 23 on the cylinder block 42 side.
Are formed. A cylindrical support member 81 having the input shaft 21 inserted therein is provided in the storage hole 78. The support member 81 is integrally connected to the bottom of the housing hole 78 of the yoke 23 via a plurality of pins 82. The inner periphery of the support member 81 has a retainer 83 as a reciprocating motion imparting member.
Are rotatably connected via a ball bearing 84. The ball bearing 84 causes the retainer 83 to move to the cylinder block 4.
It is possible to rotate synchronously with respect to 2.

The retainer 83 has a cylindrical portion, a flange, and a locking groove that have the same structure as the retainer 70. Therefore, the same reference numerals are given to those structures and the description thereof is omitted (FIG. 6). (See (a)).

As shown in FIG. 5, the retainer 83 is arranged such that its axis intersects with the axis O by a ball bearing 84, and in this state, the input shaft 21 is rotatably penetrated. There is. The virtual plane including the surface of the flange 72 that faces the cylinder block 42 (hereinafter, referred to as the flange surface) crosses the axis O obliquely due to this crossing.

The retaining groove 73 of the retainer 83 is shown in FIG.
As shown in (b), the constricted portion 76b provided on the second switching valve 76 is engaged. The constricted portions 76b are adjacent to the large diameter portion 7 on both sides in the longitudinal direction with the tapered surfaces 76d interposed therebetween.
The diameter is smaller than 6c. The taper surface 76d is formed so that the distance from the other taper surface 76d facing the taper surface 76d becomes shorter as it goes toward the axis of the second switching valve 76. Both side surfaces of the flange 72 are arranged so as to make line contact with the tapered surface 76d.

The second switching valve 76 realizes the displacement as shown in FIG. 7 by engaging with the retainer 83 having the flange surface obliquely intersecting with the axis O. In FIG. 7, the flange 72 of the retainer 70 and the flange 7 of the retainer 83
The relative position with respect to 2 changes because the retainers 70 and 83 are rotatable, but for convenience of description, they are collectively shown as one.

Then, with the relative rotation of the yoke 23 (output rotating portion) with the cylinder block 42, the retainer 83
Due to the flange 72 of the second hydraulic device 200, the relative rotation angle of the yoke 23 (output rotation portion) with respect to the cylinder block 42 with respect to the cylinder block 42 is in the range J from 0 to 180 degrees.
The area K is given in the range of 180 degrees to 360 (0) degrees.

Here, the area J is the port W and the first oil chamber 6
1 is an area including all the communicating sections, and an area K
Is an area including the entire section where the port W and the second oil chamber 62 communicate with each other.

Further, in the present embodiment, when the swash plate surface 44 tilts to the negative side as shown in FIG. 3, the relative rotation angle 0 to 180 of the yoke 23 (output rotating portion) about the axis O with respect to the cylinder block 42. In the range of degrees, the hydraulic oil is sucked into the plunger hole 57 through the port W, and 180 to 360 (0)
Hydraulic fluid through the port W to the plunger hole 5
It is discharged from 7. When the swash plate surface 44 tilts to the positive side, the cylinder block 42 of the yoke 23 (output rotation part)
The working oil is discharged from the plunger hole 57 through the port W in the range of the relative rotation angle of 0 to 180 degrees with respect to the axis O, and the working oil is discharged through the port W in the range of 180 to 360 (0) degrees. Inhaled into the hole 57. The oil chamber to be discharged and the oil chamber to be sucked are determined by regions J and K corresponding to the relative rotation angle of the yoke 23 (output rotating portion) with respect to the cylinder block 42 about the axis O.

The plunger hole 47 and the plunger hole 5
7, first oil chamber 61, second oil chamber 62, first valve hole 63, second
Valve hole 64, oil passage 65, oil passage 75, port U and port W
A closed hydraulic circuit C is constituted by and.

As shown in FIGS. 1 and 3, a shaft hole 99 is formed along the axis O in the input shaft 21 for charging the hydraulic closed circuit C with hydraulic oil. The shaft hole 99 has an introduction oil passage 99a in a radial direction at a portion corresponding to the sleeve 37. The introduction oil passage 99a has a sleeve 3
7 communicates with an oil passage 37a formed in the radial direction and a circumferential groove 37b formed on the outer peripheral surface. The side wall member 30 is provided with an oil passage 30a communicating with the circumferential groove 37b.
Hydraulic fluid is pumped into the inside of a from a charge pump (not shown). Further, in the shaft hole 99, a plug 121 is screwed into an opening on the output end side of the input shaft 21 so that the screwing amount can be adjusted.

On the other hand, in the input shaft 21, the first oil chamber 61
A charge valve 90 (check valve) that opens and closes a valve body that can communicate with the shaft hole 99 is disposed in each of the second oil chambers 62. The valve element of the charge valve 90 opens until the hydraulic pressure in the hydraulic closed circuit C reaches the charge pressure in the shaft hole 99, and supplies the hydraulic oil in the shaft hole 99 to the hydraulic closed circuit C. The charge valve 90 also prevents hydraulic oil from flowing back to the shaft hole 99.

Now, the reciprocating state of the first and second switching valves 66 and 76 in the continuously variable transmission 20 (first and second hydraulic devices 100 and 200) configured as described above will be described.

With the rotation of the cylinder block 42, the switching valves 66 and 76 reciprocate along the direction of the axis O due to the engagement relationship with the retainers 70 and 83 having the flange surfaces obliquely intersecting the axis O. At this time, the retainers 70 and 83 rotate together with the cylinder block 42 and relatively rotate with respect to the swash plate surface 44 or the yoke 23 (rotational inclined surface 51). Switching valve 6
The base end portions of 6,6 are the bottom portions 63a, 64 of the valve holes 63, 64.
When approaching a, the flange surface advances toward the cylinder block 42 side due to the rotation of the cylinder block 42.
Then, the flanges 7 of the retainers 70 and 83 that are in line contact with the tapered surfaces 66d and 76d of the switching valves 66 and 76.
Of the two side surfaces of 2, the flange surface is the cylinder block 42
The tapered surfaces 66d and 76d on the side are pressed. At this time, since the flange surface is in line contact with the tapered surfaces 66d and 76d, the load at the contact portion is reduced, and the durability is improved as compared with the case of point contact.

On the other hand, the base ends of the switching valves 66 and 76 are provided with the valve hole 6
When separated from the bottom portions 63a and 64a of the cylinders 3 and 64, the flange surface retreats toward the side opposite to the cylinder block 42 due to the rotation of the cylinder block 42. Then, the tapered surface 66
Among the both side surfaces of the flange 72 which are in line contact with d and 76d, the non-flange surface (the back surface of the flange surface) presses the taper surfaces 66d and 76d on the non-cylinder block 42 side. At this time as well, the anti-flange surface (the back surface of the flange surface) is in line contact with the tapered surface 66d, and the load at the contact point is reduced as compared with the case of point contact.

In this embodiment, unlike the prior art, the switching valve 6
Instead of abutting the tips of 6, 6 with the swash plate, the constricted portions 66b, 76b of the switching valves 66, 76 and the retainer 7 are provided.
Reciprocation is realized by the engagement relationship of the engaging grooves 73 of 0 and 83. Therefore, in order to bring the tips of the switching valves 66 and 76 into contact with the swash plate, the switching valve 6 is driven by a spring or the like from the side opposite to the swash plate.
It is not necessary to press 6,76 to the swash plate side.

(Operation) Now, the operation of the continuously variable transmission 20 constructed as described above with the tilting of the cradle 45 will be described. In addition, from the crankshaft of the engine 22 to the input shaft 2
For convenience of description, the input rotation speed Nin given to 1 will be described as a constant value.

(When the output speed Nout is Nin) FIG. 11
Operate the shift lever 146 shown in to operate the cradle 45.
The swash plate surface 44 is positioned at the upright position via the.

In this state, the driving force of the engine 22 causes the cylinder block 42 to rotate in the forward direction Nin via the input shaft 21. After that, gear 14 in the opposite direction to Nin
2 or the time when the output shaft 155 rotates is referred to as forward rotation. The swash plate surface 44 is in a neutral state in an upright position with respect to the axis O of the input shaft 21. Plunger 4 of the first hydraulic device 100
3 is not reciprocated by the swash plate surface 44, and therefore in this state the hydraulic oil does not circulate in the hydraulic closed circuit C. Therefore, on the side of the second hydraulic device 200, each plunger 58 is
Shoe 60 with the protruding end of the
Since the rotary slope 51 is brought into contact with and engaged with the rotary slope 51 via the cylinder, the cylinder block 42 and the rotary slope 51 are directly connected to each other and integrally rotate. That is, in this state, the input shaft 21 and the gear 14
2 is directly connected. The rotation in the forward direction imparted to the rotary slope 51 is transmitted to the final reduction gear via the yoke 23, the connected first clutch 139, the gear 141, and the gear 142.

When the swash plate surface 44 is in the upright position, the stroke volume VP of the first hydraulic system 100 becomes 0, and the output speed Nout (yoke 23
The rotation speed of is the input rotation speed Nin.

(When the output speed Nout is between Nin and 2Nin) The shift lever 146 is operated to move the cradle 45.
The swash plate surface 44 is tilted to the negative side via the and to be positioned in a region between a predetermined negative tilt angle position and the upright position. The predetermined negative tilt angle position is a position until the absolute value of the stroke volume VP of the first hydraulic device 100 becomes equal to the absolute value (= VMmax) of the stroke volume VM of the second hydraulic device 200.

In this case, the driving force of the engine 22 causes the cylinder block 42 to rotate at Nin via the input shaft 21. Then, the first hydraulic device 100 sucks the working oil into the plunger hole 47 through the port U within the range of the rotation angle of 0 to 180 degrees around the axis O of the cylinder block 42,
The hydraulic oil is discharged from the plunger hole 47 through the port U within the range of 0 to 360 (0) degrees. The oil chamber for discharging and sucking is determined by the regions H and I corresponding to the rotation angle of the cylinder block 42 around the axis O. The amount of hydraulic oil discharged and sucked by the first hydraulic device increases as the tilt angle of the swash plate surface 44 toward the negative side increases. At this time, in the second hydraulic device 200, the relative rotation angle 0 to 18 of the yoke 23 (output rotation portion) with respect to the cylinder block 42 about the axis O.
The working oil is sucked into the plunger hole 57 through the port W in the range of 0 degree, and the working oil is discharged from the plunger hole 57 through the port W in the range of 180 to 360 (0) degrees.
The oil chamber to be discharged and the oil chamber to be sucked are determined by regions J and K corresponding to the relative rotation angle of the yoke 23 (output rotating portion) with respect to the cylinder block 42 about the axis O.

As a result, the rotation speed Nin at which the cylinder block 42 is driven via the input shaft 21 and the plunger 58
The rotational slope 51 is rotated by combining (summing) with the number of rotations in the positive direction due to the protrusion pressing action on the rotational slope 51. The rotation in the positive direction imparted to the rotation slope 51 is generated by the yoke 2
3, the first clutch 139, the gear 141, and the gear 142, which are connected to each other, are transmitted to the final reduction gear transmission as rotation in the forward direction, and the speed-up action is performed.

At this time, when the swash plate surface 44 is displaced from the upright position to the side of the predetermined negative tilt angle position, the stroke volume VP of the first hydraulic system 100 increases from 0 to VMmax in FIG. Output speed Nout is 2N from Nin
Speed up to in. In addition, the output speed Nout is 2 from Nin.
Stroke volume V of the second hydraulic device 200 when changing to Nin
M remains at VMmax. The flow and rotation of the hydraulic oil in this state are shown in FIG. 10. At this time, in the hydraulic closed circuit C, the hydraulic oil flows as shown by the arrows in the figure. The arrows attached to Nin and Nout indicate the rotation directions of the corresponding members.

(When the output speed Nout is between 0 and Nin) The shift lever 146 is operated to tilt the swash plate surface 44 to the positive side through the cradle 45 to move it from the upright position to the positive tilt angle position. Position it. Note that, of the positive tilting angle positions, the predetermined positive tilting angle position means the first hydraulic device 100.
This is the position until the absolute value of the stroke volume VP becomes equal to the absolute value of the stroke volume VM of the second hydraulic device 200.

In this case, since the swash plate surface 44 tilts in the positive direction, when the cylinder block 42 rotates via the input shaft 21 by the driving force of the engine 22, the first hydraulic device 10
0 is a rotation angle 0 around the axis O of the cylinder block 0.
The working oil is discharged from the plunger hole 47 through the port U in the range of 180 degrees, and the working oil is sucked into the plunger hole 47 through the port U in the range of 180 to 360 (0) degrees. The discharging oil chamber and the sucking oil chamber have regions H and I corresponding to the rotation angle around the axis O of the cylinder block 42.
Depends on The amount of hydraulic oil discharged and sucked by the first hydraulic device 100 increases as the tilt angle of the swash plate surface 44 toward the positive side increases. At this time, the second hydraulic device 20
0 is the cylinder block 4 of the yoke 23 (output rotating part)
2, the working oil is discharged from the plunger hole 57 through the port W in the range of a relative rotation angle of 0 to 180 degrees around the axis O, and the working oil is discharged through the port W in the range of 180 to 360 (0) degrees. And inhales into the plunger hole 57. The oil chamber to be discharged and the oil chamber to be sucked are determined by regions J and K corresponding to the relative rotation angle of the yoke 23 (output rotating portion) with respect to the cylinder block 42 about the axis O.

As a result, the rotation slope 51 of the plunger 58 is
The output pressing speed Nout is N
rotation between "in and 2Nin". Therefore, the composite (sum) of the rotation speed in the reverse direction and the rotation speed in the positive direction of the cylinder block 42 is transferred to the final reduction gear transmission via the yoke 23, the connected first clutch 139, the gear 141, and the gear 142. Transmitted. Since the sum of the rotational speeds at this time becomes the rotational speed in the forward direction reduced by the rotational speed in the reverse direction, the output rotational speed Nout becomes smaller than that in the case where the output rotational speed Nout is Nin.

In this embodiment, when the swash plate surface 44 is displaced from the upright position to the positive maximum tilt angle position side at this time,
In FIG. 12, the stroke volume VP of the first hydraulic device 100 is 0.
To -VMmax (the "-" is from the port U to the second oil chamber 62)
It means that the ink is discharged to. ) Side, and the output speed Nout decelerates accordingly from Nin to 0.

The output speed Nout at this time is Nin
The stroke volume VM per rotation of the second hydraulic device 200 when changing from 0 to 0 is -VMmax. (The "-" means the case of being sucked into the port W from the second oil chamber 62.) FIG. 9 is a schematic view of the state at this time. First
The oil chamber 61 (oil chamber A) side is at a higher pressure side than the second oil chamber 62 (oil chamber B) side, and in the hydraulic closed circuit C, the flow of hydraulic oil as shown by the arrow in the figure Has become. Also, N
The arrows attached to in and Nout indicate the rotation directions of the corresponding members.

(When the output speed Nout is 0) The clutch mechanism 300 disconnects the input rotation Nin from the engine 22 to stop the yoke 23.

(When the output speed Nout is less than 0) When the shift lever 146 is shifted to the reverse drive side with the clutch mechanism 300 in the disengaged state, the first clutch of the gear shift device 138 responds to the operation of the shift lever 146. 139
Is disengaged and the second clutch 140 is engaged. At this time, the rotation from the engine 22 side is not transmitted to the continuously variable transmission 20, so that the pressing action of the plunger 58 on the rotating slope 51 is lost, and the yoke 23 becomes free from the second hydraulic device 200. Therefore, the second yoke 23
It is possible to easily connect the clutch 140, that is, to switch the vehicle in reverse. Then, after shifting the shift lever 146 to the reverse drive side, the clutch mechanism 300 is brought into the connected state again. Even when returning to the forward side, the clutch pedal is depressed to put the clutch mechanism 300 into the disengaged state. At this time, it is possible to easily perform switching during forward movement for the same reason.

(When the output speed Nout is between 0 and -Nin) After the reverse connection by the second clutch 140 is performed, as shown in FIG. 9, the output speed Nout and the first hydraulic system 100 and The change state of the maximum stroke volume of the second hydraulic device 200 is the same as in the case of forward movement (normal rotation) and is the same as the description (when the output speed Nout is between 0 and Nin), and therefore the description thereof is omitted. FIG. 9 shows the flow and rotation direction of the hydraulic oil. In this case, the rotation imparted to the rotary slope 51 is transmitted to the final reduction gear transmission through the yoke 23, the second clutch 140, the gear 143, the idler gear 144, the idler gear 145, and the gear 142.

(When the output speed Nout is between Nin and -2Nin) Also in this case, the action of the first hydraulic device 100 and the second hydraulic device 200 is (when the output speed Nout is between Nin and 2Nin). Since it is the same as, the description will be omitted. Figure 10
Indicates the flow and rotation direction of the hydraulic oil. Also in this case, the rotation imparted to the rotation slope 51 is generated by the yoke 23, the second clutch 140, the gear 143, the idler gear 144,
It is transmitted to the final reduction gear via the idler gear 145 and the gear 142.

Therefore, according to the above embodiment, the following effects can be obtained. (1) In the above embodiment, the retainers 70 and 83 engage and hold the switching valves 66 and 76, and as the cylinder block 42 rotates, the flange surface or the non-flange surface (the back surface of the flange surface) is tapered surface 66d, By pressing 76d, the switching valves 66 and 76 can be reciprocated.

Conventionally, there is known a ball bearing in which the axial center of the switching valves 66, 76 (corresponding to distribution valves) is inclined at a constant angle with respect to the axis O of the cylinder block 42. Therefore, the side surface (corresponding to a swash plate) of the inner ring of the ball bearing is used as a cam surface for reciprocating the switching valves 66, 76. Further, springs are provided in the bottom portions 63a and 64a of the valve holes 63 and 64 located on the base end sides of the switching valves 66 and 76, and the working oil from the charge pump is filled. Then, the switching valves 66 and 76 are constantly urged toward the ball bearing side by the spring force of the spring and the hydraulic pressure of the hydraulic oil. Then, with the switching valves 66, 76 in contact with the side surface of the inner ring of the ball bearing, which is a swash plate, the ball bearing together with the cylinder block 42 rotates around the axis O so that the switching valves 66, 76 are rotated. It was supposed to be reciprocated.

However, in order to reciprocate the switching valves 66 and 76, a spring, an oil passage, etc. must be provided.
The structure was complicated and the cost was high.

Therefore, according to the configuration of the present embodiment, the switching valve 66 is compared with the configuration in which the side surface of the inner ring of the ball bearing, which is the swash plate, and the switching valves 66 and 76 are held in contact with each other. ，
It is not necessary to provide a spring for pressing 76 against the swash plate. Similarly, since it is not necessary to fill the hydraulic oil from the charge pump into the bottom portions 63a and 64a of the valve holes 63 and 64, it is not necessary to provide an oil passage or the like for that purpose. Recently, it has been desired to reduce the number of parts in manufacturing the continuously variable transmission 20, and it has been desired to simply and reciprocally move the switching valves 66 and 76. Therefore, since the spring and the oil passage are not provided, the reciprocating structure of the switching valves 66 and 76 can be simplified. In addition to this, the reduction in the number of parts can contribute to the reduction in manufacturing cost.

(2) In the above embodiment, tapered surfaces 66d are formed on both sides in the longitudinal direction of the constricted portions 66b and 76b which engage with the locking groove 73 of the flange 72, and both side surfaces of the flange 72 are opposed to the tapered surface 66d. It was arranged so as to make line contact. Therefore, for example, the flange 72 and the switching valves 66 and 76
Compared with the case of making point contact with and, when the reciprocating motion of the switching valves 66, 76, the load at the contact portion can be reduced and the durability can be improved.

(3) In the above embodiment, the continuously variable transmission 2
0 is configured such that the cylinder block 42 is rotated by the input shaft 21 from the engine 22 (motor).
1 is extended to the side opposite to the engine 22, and the extended input shaft 2
1. A yoke 23 (output rotating portion) is provided on the outer periphery of the yoke 1.
A gear shift device 138 (forward / reverse rotation switching device) that transmits power in the same rotation direction as or in the reverse direction is provided, and a clutch mechanism 300 (connection / disconnection means) that turns on / off the rotation transmission to the input shaft 21 of the engine 22. Was provided as a power transmission device. Therefore, the effect of the continuously variable transmission 20 is also exhibited in the power transmission device.

(4) In the above embodiment, output rotation can be obtained from both the input shaft 21 and the yoke 23 extended to the output side. Further, the rotation of the yoke 23 can transmit a wide range of driving torque to the final reduction gear device in the forward and reverse directions by the tilt angle of the cradle 45 and the gear shift device 138.

(5) In the above-described embodiment, the clutch mechanism 300 is disengaged to release the torque applied to the yoke 23 when the rotation of the yoke 23 is switched (forward → reverse or reverse → forward). The rotation can be easily switched.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, the same or corresponding configurations as those of the previously described embodiments are designated by the same reference numerals and the description thereof will be omitted.

The part of this embodiment different from the first embodiment is the structure for imparting reciprocating motion to the switching valves 66, 76 including the valve actuation imparting members 170, 183. As shown in FIGS. 13 and 15, the first switching valve 66 has a first
Coil spring 6 arranged at the bottom 63a of the valve hole 63
7, the plunger 43 is urged in the same direction as the direction in which the plunger 43 projects from the cylinder block 42. In addition, FIG.
As shown in FIG. 7, the tip portion of the first switching valve 66 protruding from the cylinder block 42 (hereinafter referred to as the contact end 66a)
Is formed in a substantially conical shape.

As shown in FIG. 14, the holder 68 fixed to the outer peripheral surface of the outer ring 39a of the conical roller bearing 39 is formed in a cylindrical shape, and the accommodating portion 68a on the cylinder block 42 side of the inner peripheral surface thereof has a needle bearing. A valve actuation imparting member 170 is rotatably supported via 110. With this needle bearing 110, the valve operation imparting member 1
70 is rotatable in synchronization with the cylinder block 42.

Here, the valve actuation imparting member 170 will be described in detail. The valve actuation imparting member 170 is formed in a cylindrical shape, and a through hole 170a is formed in a substantially central portion thereof. The valve actuation imparting member 170 is arranged such that its axis X is offset in parallel to the axis O of the cylinder block 42 by a predetermined distance e. The input shaft 21 is inserted through the through hole 170a. The axis O corresponds to the cylinder block axis.

A cam portion 171 is formed on the cylinder block 42 side of the valve actuation imparting member 170 so as to communicate with the through hole 170a. The inner peripheral surface of the cam portion 171 is a conical surface that is formed in a tapered shape and expands toward the cylinder block 42 side. Further, the valve actuation imparting member 170 including the cam portion 171 has the axis X of the valve actuation imparting member 170.
On the other hand, when viewed in a cross section along the coaxial line X, they are formed in line symmetry. Inner peripheral surface (conical surface) of the cam portion 171
Corresponds to the slope.

The conical abutting end 6 of the first switching valve 66.
6a is formed so as to make line contact with the inner peripheral surface of the cam portion 171, and is in contact with the conical surface of the cam portion 171. Therefore, the biasing force of the coil spring 67 and the hydraulic pressure of the hydraulic oil by a charge pump (not shown) described later are applied to the first switching valve 66, so that
The switching valve 66 rotates synchronously with the cylinder block 42 while being held in contact with the valve actuation imparting member 170. Also,
While the cylinder block 42 makes one revolution around the axis O by the axis X of the valve actuation imparting member 170 being offset with respect to the axis O of the cylinder block 42, the first switching valve 66 moves to the cam portion 171. It reciprocates along the axis O in the direction of the distance D1 to realize the displacement shown in FIG.

Therefore, with the rotation of the cylinder block 42, the first switching valve 66 has a first opening position n1 which connects the port U (oil passage 65) and the second oil chamber 62 with the port closing position n0 as the center. , Between the port U (oil passage 65) and the second opening position n2 that communicates the first oil chamber 61 with each other along the direction of the axis O (see FIG. 7). The distance D1 is
In FIG. 7, it is the distance between the second opening position n2 and the first opening position n1.

Further, due to the cam portion 171, the first hydraulic system 100 has regions H, 1 within the range of 0 to 180 degrees corresponding to the rotational direction of the cylinder block 42 around the axis O.
The region I is given in the range of 80 degrees to 360 (0) degrees.

On the other hand, as shown in FIGS. 13 and 14, the second switching valve 76 has a direction in which the plunger 58 projects from the cylinder block 42 due to the coil spring 77 arranged at the bottom 64a of the second valve hole 64. It is biased in the same direction. Further, as shown in FIG. 15, a tip portion (hereinafter, referred to as a contact end 76a) of the second switching valve 76 protruding from the cylinder block 42 is formed in a substantially conical shape.

As shown in FIG. 15, a housing hole 78 formed at the center of the end surface of the yoke 23 on the cylinder block 42 side.
A cylindrical holder 93 is fixed inside. On the inner peripheral surface of the holder 93, the cylinder block 42 side is formed as an enlarged diameter portion 93a having an enlarged diameter, and the enlarged diameter portion 93a is provided with a valve bearing imparting member 1 via a needle bearing 94.
83 is rotatably supported. The needle bearing 94 allows the valve actuation imparting member 183 to rotate synchronously with the cylinder block 42.

The counter cylinder block 4 of the holder 93
The second side is a reduced diameter portion 93b, and a support member 95 is rotatably inserted in the reduced diameter portion 93b. The input shaft 21 is passed through the support member 95, and the support member 95 is fixed to the input shaft 21. The valve actuation imparting member 183 is held by the support member 95 via a shim 96.

Here, the valve actuation imparting member 183 will be described in detail. The valve actuation imparting member 183 is formed in a cylindrical shape, and a through hole 183a is formed at a substantially central portion thereof. The valve actuation imparting member 183 is arranged such that its axis Y is offset in parallel to the axis O of the cylinder block 42 (input shaft 21) by a predetermined distance f. The input shaft 21 is inserted through the through hole 183a. In addition,
Offset amount in the first hydraulic device 100 (predetermined distance)
e and the offset amount (predetermined distance) f in the second hydraulic device 200 are the same amount.

A cam portion 184 is formed on the cylinder block 42 side of the valve actuation imparting member 183 so as to communicate with the through hole 183a, and the inner peripheral surface of the cam portion 184 is tapered to expand to the cylinder block 42 side. It is a conical surface formed in a shape. Further, the valve actuation imparting member 183 including the cam portion 184 is formed in line symmetry with respect to the axis Y of the valve actuation imparting member 183 when viewed in a cross section taken along the coaxial line Y. The inner peripheral surface (conical surface) of the cam portion 184 corresponds to an inclined surface.

The conical contact end 76a of the second switching valve 76 is formed so as to be in linear contact with the cam portion 184, and is in contact with the cam portion 184.
As a result, the urging force of the coil spring 77 and the hydraulic pressure of hydraulic oil by a charge pump (not shown) described later are applied to the second switching valve 76, so that the second switching valve 76 causes the valve operation applying member 183 to operate. It rotates synchronously with the cylinder block 42 in the state of being held in contact with it. Further, the axis Y of the valve actuation imparting member 183 is the axis O of the cylinder block 42.
Since the cylinder block 42 makes one turn around the axis O, the second switching valve 76
Moves reciprocally along the cam portion 184 in the direction of the axis O by a distance D2 to realize the displacement shown in FIG. In addition,
The reciprocating distance D1 of the first switching valve 66 and the reciprocating distance D2 of the second switching valve 76 are made equal.

Incidentally, in FIG. 7, the valve actuation applying member 17
0, the conical surface of the cam portion 171 and the valve actuation imparting member 1
The relative position of the cam portion 184 with respect to the conical surface at 83 changes because the valve actuation imparting members 170 and 183 are made rotatable, but for convenience of explanation, they are collectively shown as one.

Then, with the relative rotation of the yoke 23 (output rotating portion) with the cylinder block 42, the cam portion 184 of the valve actuation applying member 183 causes the yoke 23 (output rotating portion) in the second hydraulic device 200. Relative rotation angle about the axis O with respect to the cylinder block 42 of 0 degrees to 180 degrees
The area J is given in the range of degrees, and the area K is given in the range of 180 to 360 (0) degrees.

As shown in FIGS. 13 to 15, an oil passage 97 is formed in the input shaft 21 at a position facing the first valve hole 63 so as to communicate with the shaft hole 99 in the radial direction.
Circular grooves 98 are formed on the inner peripheral surface of the cylinder block 42 so as to be inserted into the bottom portions 63a and 64a of the first and second valve holes 63 and 64, respectively, and the peripheral grooves 98 are connected to the oil passage 97. There is. As a result, the bottom portions 63a of the first and second valve holes 63 and 64 in which the coil springs 67 and 77 are arranged,
64a is filled with hydraulic oil from the charge pump through the shaft hole 99, the oil passage 97, and the circumferential groove 98.

In this embodiment, the valve actuation imparting member 170,
Each of 183 corresponds to a reciprocating motion imparting member. here,
The reciprocating state of the first and second switching valves 66 and 76 in the continuously variable transmission 20 (first and second hydraulic devices 100 and 200) configured as described above will be described.

First, the bottom 63 of the valve holes 63, 64
The switching valves 66 and 76 are always operated by the valve actuation imparting members 170 and 183 in cooperation with the hydraulic pressure inside the a and 64a and the urging force of the coil springs 67 and 77 at the bottoms 63a and 64a.
Is pressed toward the cam portions 171, 184, and is held in contact therewith.

Then, with the rotation of the cylinder block 42, the switching valves 66 and 76 reciprocate along the direction of the axis O. At this time, the valve actuation imparting members 170 and 183 rotate synchronously with the cylinder block 42 and relatively rotate with respect to the swash plate surface 44 or the yoke 23 (rotational slope 51). When the base ends of the switching valves 66, 76 approach the bottoms 63a, 64a of the valve holes 63, 64, the cylinder block 42 rotates to contact the contact ends 66a, 76a on the conical surface of the cam portion 171. The contact portion advances to the cylinder block 42 side. Then, the contact ends 66a and 76a of the switching valves 66 and 76 are pushed toward the cylinder block 42 side. Then, the moving switching valves 66 and 76 contract the coil springs 67 and 77 against the biasing force of the coil springs 67 and 77, and the hydraulic oil with which the bottom portions 63a and 64a of the valve holes 63 and 64 are filled is surrounded by the circumferential groove 98. Is discharged to.

On the other hand, the base ends of the switching valves 66 and 76 are provided with the valve hole 6
When separated from the bottom portions 63a and 64a of the cams 3 and 64, the cam portions 171 and 18 are rotated by the rotation of the cylinder block 42.
The portion of the conical surface 4 that contacts the contact ends 66a and 76a retreats toward the side opposite to the cylinder block 42. At this time, the elastic force when the contracted coil springs 67 and 77 are restored, and the bottom groove 63 of the valve holes 63 and 64 from the circumferential groove 98.
The hydraulic pressure of the hydraulic oil filled in a and 64a
Hanging on 6. Then, the first and second switching valves 66 and 76 move so as to project from the cylinder block 42 while the contact ends 66 a and 76 a thereof are in contact with the cam portions 171 and 184.

At this time, the contact ends 66 of the switching valves 66 and 76 are
a, 76a are not brought into contact with the swash plate but are brought into contact with the cam portions 171 and 184 which are formed in a tapered shape and expand toward the cylinder block 42 side, so that the switching valves 66 and 76 reciprocate. Has been realized. Then, the valve actuation imparting member 17
0,183 (cam parts 171 and 184) have their own axis X,
Since the cross-sectional shape is axisymmetric with respect to Y, it is easy to improve the balance in the direction of the axis O of the cylinder block 42.

Therefore, according to this embodiment, in addition to the effects described in (3) to (5) in the first embodiment,
The following effects can be obtained. (1) In the above embodiment, the cam portions 171 and 184 are provided on the cylinder block 42 side of the valve actuation imparting members 170 and 183 that rotate in synchronization with the cylinder block 42, and the inner peripheral surface thereof is formed as a conical surface. . The axes X and Y of the valve actuation imparting members 170 and 183 are offset from the axis O of the cylinder block 42 by a predetermined distance e or f. As a result, when the cylinder block 42 rotates, reciprocating motion is imparted to the switching valves 66 and 76.

Conventionally, on the tip side of the switching valves 66 and 76,
It is known to arrange a ball bearing whose axis is inclined at a constant angle with respect to the axis O of the cylinder block 42, and the side surface (corresponding to a swash plate) of the inner ring of the ball bearing reciprocates the switching valve. It was used as a cam surface for moving. Further, the valve holes 63, 6 located on the base end side of the switching valves 66, 76.
The bottoms 63a and 64a of No. 4 were provided with springs and filled with hydraulic oil from the charge pump. Then, the switching valves 66 and 76 are constantly urged toward the ball bearing side by the spring force of the spring and the hydraulic pressure of the hydraulic oil. Then, with the switching valves 66 and 76 in contact with the side surface of the inner ring of the ball bearing that is the swash plate, the ball bearing together with the cylinder block 42
By rotating around the axis O, the switching valves 66, 7
Reciprocating motion was added to 6.

However, this is because the side surface (swash plate) of the inner ring of the ball bearing is used as the cam surface for imparting reciprocating motion to the switching valves 66 and 76, so that the cylinder block 4 is rotated during rotation.
There is a problem that an unbalanced state occurs, which is relatively difficult to improve in design in the two axis directions.

Therefore, unlike the prior art, the member is not in contact with the obliquely arranged members (swash plates), but is a conical surface (cam portion 171, which has a cross section symmetrical with respect to the axes X and Y).
184), the balance can be easily corrected in the direction of the axis O when the switching valves 66 and 76 reciprocate.

The above embodiments may be modified and embodied in the following different examples. In the first embodiment, the tapered surfaces 66d and 76d are formed on both sides in the longitudinal direction of the constricted portions 66b and 76b that engage with the locking groove 73 of the flange 72, but as shown in FIG. The tapered surfaces 66d and 76d may not be formed. In this case, the contact side surface of each flange 72 is in point contact with the large diameter portions 66c and 76c of the switching valves 66 and 76.

In the first embodiment, the retaining groove 73 is provided in the flange 72 of the retainer 70, while the switching valve 6 is provided.
Although the constricted portions 66b and 76b are provided on the reference numerals 6 and 76 and are engaged with each other to reciprocate the switching valves 66 and 76, the configuration shown in FIGS. 16 (a) and 16 (b) may be adopted. . That is, as shown in FIG. 16A, the retainers 70, 83
Is composed of a cylindrical tubular portion 71, and an engagement projection 172 that is formed so as to project at equal angles over the circumferential edge of the cylindrical portion 71 on the cylinder block 42 side. As shown in FIG. 16B, the engagement protrusion 172 is formed in an L shape.

The retainers 70 and 83 are arranged such that their shaft centers are oblique to the axis O by the ball bearings 69 and 84. Therefore, the surfaces of the engaging projections 172 facing the cylinder block 42 are arranged. The included virtual plane intersects the axis O obliquely.

On the other hand, engaging holes 176 are formed in the switching valves 66 and 76, and the engaging projections 172 are engaged therein. Both openings of the engagement hole 176 are tapered surfaces 176a.
Both side surfaces of the engagement projection 172 are in line contact with the tapered surface 176a. Even in this case, the same effect as that of the second embodiment can be obtained. 16B shows the retainer 8 on the second hydraulic device 200 side.
3 is illustrated, the retainer 70 on the first hydraulic device 100 side has the same configuration.

Also, the retainer 7 of the first embodiment.
0 and 83 may be configured as shown in FIG. That is, the flange 72 of the retainer 70, 83 and the switching valve 66,
The tip portion of 76 is connected by a member having elasticity in a bending direction such as a piano wire 173. Even in this way, the flange 72
When the flange surface of the cylinder advances or retreats toward the cylinder block 42 side, the switching valves 66, 76 are connected via the piano wire 173.
Can be reciprocated. Note that FIG. 17 shows the second hydraulic device 2.
Although the retainer 83 on the 00 side is illustrated, the retainer 70 on the first hydraulic device 100 side has the same configuration.

That is, in the first embodiment, the retainers 70 and 83 and the first switching valve 66 and the second switching valve 76, which are distribution valves, are directly engaged with each other, but in the present embodiment,
The retainer 70, 83 is indirectly connected to the first switching valve 66 and the second switching valve 76, which are distribution valves, by a piano wire 173 or the like which is a connecting member.

In the first and second embodiments, the structure of the gear shift device 138 may be changed to the structure of the gear shift device 150 (CST) shown in FIG. In the gear shift device 150, as shown in the figure, an output gear 24 is formed at a protruding end of a yoke 23, and a forward clutch 152 and a reverse clutch that are connected to an output shaft 155 that transmits a driving torque to a final reduction gear (not shown). 153 is provided. It also has the following gear trains.

The drive side clutch plate of the forward clutch 152 has a gear 151 meshed with the output gear 24. When the forward clutch 152 is connected by operating the shift lever 146, the yoke 23, the output gear 24, the gear 151, the forward clutch 152, and the output shaft 155.
The drive torque is transmitted to the final reduction gear device (not shown) via.

Further, the output gear 24 is provided with an idler gear 15
6, a reverse clutch 153 via an idler gear 157 and an intermediate gear 159 having a common shaft with the idler gear 156.
A gear train consisting of a gear 160 connected to the driving side clutch plate is connected. And the clutch mechanism 3
When the reverse clutch 153 is engaged by the backward operation of the shift lever 146 after disconnecting 00, the driving torque is transmitted to the final reduction gear device (not shown) via the gear train and the output shaft 155. In this embodiment, the gear shift device 150 corresponds to the forward / reverse rotation switching device.

In the first and second embodiments described above, the continuously variable transmission 20, and further the first hydraulic device 100 or the second hydraulic device 200 used for the power transmission device are used as the plunger 4.
Instead of the axial type in which 3, 58 reciprocate in the axial direction, a radial type in which the plunger reciprocates in the radial direction of the axis may be used.

In the second embodiment described above, the inner peripheral surfaces of the cam portions 171 and 184 of the valve actuation imparting members 170 and 183 are conical surfaces formed in a tapered shape that expands toward the cylinder block 42 side. However, it may be formed in a hemispherical shape. Further, if it is not a conical surface or a hemispherical surface, a surface having a parabolic cross section or another shape may be used as long as it satisfies the following configuration.

In the above embodiment, the cam portions 171, 18
Although a conical surface that expands in diameter toward the cylinder block 42 side is formed on the inner peripheral surface of No. 4, and the switching valves 66 and 76 are brought into contact with each other, the outer peripheral surface of the valve actuation imparting members 170 and 183 is set to the cylinder block 42
It is also possible to adopt a mode in which it is formed in a conical shape whose diameter decreases toward the side and abuts on the outer peripheral surface. In this case, the outer peripheral surfaces of the valve actuation imparting members 170 and 183 correspond to slopes.

Next, the technical ideas that can be understood from the above-described embodiment and each other example will be described below together with their effects. (1) The hydraulic continuously variable transmission according to claim 1, wherein the distribution valve engaged and the reciprocating motion imparting member are in line contact with each other. . By doing so, the load on the engaging portion can be reduced, and the durability can be improved.

[0132]

As described in detail above, according to the first aspect of the invention, a configuration in which the distribution valve can reciprocate due to the engagement relationship between the reciprocating motion imparting member and the distribution valve can be realized. The structure of can be simplified.

According to the invention of claim 2, the effect of claim 1 can be realized also in the power transmission device. According to the invention of claim 3, when the distribution valve reciprocates, it is easy to correct the axial balance of the cylinder block.

According to the invention of claim 4, the effect of claim 3 can be realized also in the power transmission device.

[Brief description of drawings]

FIG. 1 is a sectional view of a continuously variable transmission according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line BB of FIG.

FIG. 3 is a sectional view taken along line AA of FIG.

FIG. 4 is a sectional view of the same main part.

FIG. 5 is a sectional view of the same main part.

6A is a front view of a retainer as a reciprocating motion imparting member, FIG. 6B is an enlarged view of a main part, and FIG. 6C is an enlarged view of a main part of another example.

FIG. 7 is an explanatory view showing the timing when the ports are opened by the first switching valve 66 and the second switching valve 76.

FIG. 8 is a conceptual diagram of a power transmission device that also includes a continuously variable transmission.

FIG. 9 is a conceptual diagram of a continuously variable transmission that also shows the operation of the embodiment.

FIG. 10 is a conceptual diagram of a continuously variable transmission that also exhibits the same operation.

FIG. 11 is a plan view of a shifter.

FIG. 12 is a characteristic diagram similarly showing the stroke volume and the output rotation speed.

FIG. 13 is a sectional view of a continuously variable transmission according to a second embodiment.

FIG. 14 is a sectional view of an essential part of the continuously variable transmission.

FIG. 15 is a sectional view of an essential part of the continuously variable transmission of the same.

16A is a front view showing a reciprocating motion imparting member (retainer) according to another embodiment, and FIG. 16B is an enlarged view of a main part.

FIG. 17 is an enlarged view of a main part in another embodiment.

FIG. 18 is a conceptual diagram of a main part of the power transmission device.

[Explanation of symbols]

O ... Axis of cylinder block, X, Y ... Axis of reciprocating motion imparting member, 21 ... Input shaft, 22 ... Engine (motor), 2
3 ... Yoke (output rotating part), 42 ... Cylinder block,
47, 57 ... Plunger hole (plunger chamber), 70, 8
3 ... Retainer (reciprocating motion imparting member), 66 ... 1st switching valve (distribution valve), 76 ... 2nd switching valve (distribution valve), 138 ... Gear shift device (forward / reverse rotation switching device), 170, 183 ...
Valve operation imparting member (reciprocating motion imparting member), 171, 184 ...
Cam portion (slope), 300 ... Clutch mechanism (disconnection / disconnection means).

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroshi Matsuyama             1-32 Yanma, Chayamachi, Kita-ku, Osaka-shi, Osaka             ー Diesel Co., Ltd. (72) Inventor Hisanori Mori             1-32 Yanma, Chayamachi, Kita-ku, Osaka-shi, Osaka             ー Diesel Co., Ltd. (72) Inventor Kunihiko Sakamoto             1-32 Yanma, Chayamachi, Kita-ku, Osaka-shi, Osaka             ー Diesel Co., Ltd. (72) Inventor Yukio Kubota             1-32 Yanma, Chayamachi, Kita-ku, Osaka-shi, Osaka             -Agricultural machinery Co., Ltd.

Claims (4)

[Claims] 1. A cylinder block of a first hydraulic device that discharges and sucks hydraulic oil by reciprocating motion of a plunger, and a cylinder block of a second hydraulic device that has an output rotating portion that obtains output rotation by abutment of the plunger. Is configured to rotate about its axis, and a hydraulic closed circuit in which hydraulic oil circulates between the plunger chamber of the first hydraulic device and the plunger chamber of the second hydraulic device is provided in the cylinder block, and the distribution provided in the cylinder block is provided. In a hydraulic continuously variable transmission configured such that hydraulic oil circulates between the plunger chambers by the reciprocating movement of the valve, the distribution valve is arranged parallel to the axis of the cylinder block, and the distribution valve is arranged in the axial direction of the cylinder block. It is arranged to be inclined, rotates in synchronization with the cylinder block, and engages with a reciprocating motion imparting member that imparts reciprocating motion to the distribution valve. HST for. 2. The power transmission device using the hydraulic continuously variable transmission according to claim 1, wherein the cylinder block is configured to be rotated by an input shaft from a prime mover, and the input shaft is extended to an opposite prime mover side and extended. The output rotation section is provided on the outer circumference of the input shaft, and the rotation direction of the output rotation section coincides with the output rotation section.
Alternatively, a forward / reverse rotation switching device that reversely transmits power is provided,
A power transmission device comprising a connecting / disconnecting means for connecting / disconnecting rotation transmission to / from a rotating shaft of a prime mover. 3. A cylinder block of a first hydraulic device that discharges and sucks hydraulic oil by reciprocating movement of a plunger and a second hydraulic device that has an output rotating portion that obtains output rotation by abutment of the plunger, and the same cylinder block. Is configured to rotate about its axis, and a hydraulic closed circuit in which hydraulic oil circulates between the plunger chamber of the first hydraulic device and the plunger chamber of the second hydraulic device is provided in the cylinder block, and the distribution provided in the cylinder block is provided. In a hydraulic continuously variable transmission configured such that the hydraulic oil circulates between the plunger chambers due to the reciprocal movement of the valve, the distribution valve is arranged parallel to the cylinder block axis, and the tip of the distribution valve abuts the slope and the slope A reciprocating motion imparting section that is configured symmetrically with respect to its own axis, the coaxial line is displaced from the cylinder block axis, and that rotates synchronously with the cylinder block. HST being characterized in that formed on. 4. The power transmission device using the hydraulic continuously variable transmission according to claim 3, wherein the cylinder block is configured to be rotated by an input shaft from a prime mover, and the input shaft extends toward the non-prime mover side and extends. The output rotation section is provided on the outer circumference of the input shaft, and the rotation direction of the output rotation section coincides with the output rotation section.
Alternatively, a forward / reverse rotation switching device that reversely transmits power is provided,
A power transmission device comprising a connecting / disconnecting means for connecting / disconnecting rotation transmission to / from a rotating shaft of a prime mover.