JPH0826928B2 - Swash plate type hydraulic system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention (1) Field of Industrial Application The present invention relates to a swash plate type hydraulic device used as a swash plate type hydraulic pump or hydraulic motor, and particularly to a cylinder hole group in an annular arrangement. A cylinder block having an annular high-pressure oil passage and a low-pressure oil passage that are concentrically arranged, a plunger group that slides into the cylinder hole group, and a plunger block that engages with the projecting end of the plunger group and rotates with the cylinder block. And a swash plate that gives reciprocating motion to the cylinder block and are radially arranged in the cylinder block, and reciprocates between the radially outer position and the inner position of the cylinder block to alternate each cylinder hole between the high pressure oil passage and the low pressure oil passage. And a distribution valve group that communicates with the distribution valve group. The inner peripheral surface of the distribution valve group is slidably in contact with the outer end of the distribution valve group and is eccentrically arranged with respect to the center of rotation of the cylinder block. An improvement of a swash plate type hydraulic device accommodated in the casing and the eccentric ring to give.

(2) Prior Art Such a swash plate type hydraulic device has been already proposed by the present applicant and is known from Japanese Patent Laid-Open No. 61-153057.

(3) Problems to be Solved by the Invention In such a swash plate type hydraulic device, the phase relationship in the rotation direction of the cylinder block between the trunnion axis of the swash plate and the eccentric direction line of the eccentric ring has a great influence on the characteristics of the device. Despite this, in the conventional case, the swash plate is supported by the swash plate anchor supported by the casing of the apparatus, while the eccentric wheel is directly supported by the same casing, and the swash plate and the eccentric wheel are substantially supported. Since they are supported by different supporting systems, it is difficult to set the phase of the trunnion axis of the swash plate and the eccentric direction line of the eccentric ring to the desired phase due to processing errors and assembly errors.

The present invention has been made in view of such circumstances, and the phases of the trunnion axis of the swash plate and the eccentric direction lines of the eccentric ring can be accurately set as desired, and moreover, the cylinder block of the hydraulic device, the swash plate, An object of the present invention is to provide the swash plate type hydraulic device having good assembling workability and maintenance workability, in which main parts such as an eccentric wheel can be assembled together as a single assembly unit body before being incorporated into their casings. .

B. Configuration of the Invention (1) Means for Solving Problems According to the present invention in order to achieve the above object, the eccentric ring is formed separately from the casing and rotatably holds the cylinder block. A swash plate anchor supported by the cylinder holder and supporting the swash plate is detachably fixed to the casing, and the cylinder holder is integrally connected to the casing so as to be supported via the swash plate anchor. It

(2) Action The swash plate anchor and the cylinder holder are the same support system integrally connected to each other, and the swash plate anchor is attached to the swash plate anchor.
Since the eccentric wheels are supported by the cylinder holders respectively, the deviation of the phase between the trunnion axis of the swash plate and the eccentric direction line of the eccentric wheel due to machining error or assembly error is extremely small.

Further, since the cylinder block is rotatably supported by the cylinder holder that supports the eccentric wheel, the eccentric amount of the eccentric wheel with respect to the cylinder block can be accurately set.

Moreover, the hydraulic system can assemble the main parts such as the cylinder block, the swash plate, and the eccentric ring together as a single assembly unit independent of the casing together with the swash plate anchor and the cylinder holder. In this state, it is possible to efficiently attach and detach the casing.

(3) Example Hereinafter, an example of the present invention will be described with reference to the drawings.
First, in FIG. 1 and FIG. 2, the power of the engine E of the motorcycle is the crankshaft 1 from the chain type primary speed reducer 2, the hydrostatic continuously variable transmission T, and the chain type secondary speed reducer 3 in order. After that, it is transmitted to a rear wheel (not shown).

The continuously variable transmission T includes a constant displacement type swash plate hydraulic pump P and a variable displacement type swash plate hydraulic motor M according to the present invention.
Then, the crankcase 4 supporting the crankshaft 1 is used as a casing and accommodated therein.

The hydraulic pump P is an output sprocket of the primary speed reducer 2
2a is an input cylinder shaft 5 that is detachably coupled with a plurality of connecting pins 16 (only one is shown in the figure), and is rotatable relative to an inner peripheral wall of an intermediate portion of the input cylinder shaft 5 via a needle bearing 6. The pump cylinder 7 to be fitted and a large number of pump plungers 9, 9 ... which are slidably fitted into a large number and odd numbered cylinder holes 8, 8 ... Of an annular array provided so as to surround the center of rotation of the pump cylinder 7. And a pump swash plate 10 that abuts the outer ends of these pump plungers 9, 9 ..., and this pump swash plate 10 on the axis of the pump cylinder 7 about a virtual trunnion axis O ₁ orthogonal to the axis of the pump cylinder 7. On the other hand, a pump swash plate holder 12 which supports the back surface of the swash plate 10 via a thrust roller bearing 11 in order to hold the swash plate at a certain angle. This pump swash plate holder 12
Is spline-fitted 13 on the inner peripheral wall of the outer end of the input cylinder shaft 5 so as to be disengageable, and is temporarily fixed by a circlip 14.

Thus, the pump swash plate 10 can reciprocate the pump plungers 9, 9 ... While the input cylinder shaft 5 is rotating to repeat the suction and discharge strokes.

In order to improve the followability of the pump plunger 9 with respect to the pump swash plate 10, a coil spring 15 that biases the pump plunger 9 in the extension direction is contracted in the cylinder hole 8.

On the other hand, the hydraulic motor M includes a motor cylinder 17 coaxially arranged to the left of the pump cylinder 7 and a large number of odd cylinder holes arranged in an annular array in the motor cylinder 17 so as to surround the rotation center. A large number of motor plungers 19, 19 ... which are respectively slidably attached to 18, 18 ... And a motor swash plate 20 which abuts on the outer ends of these motor plungers 19, 19.
A trunnion shaft 22 having a half-moon-shaped cross section that supports the back surface of the motor swash plate 20 as a flat surface via a thrust roller bearing 21, and a swash plate anchor 23 that rotatably supports the cylindrical surface of the trunnion shaft 22. Composed of. Swashplate anchor 23
Is fixed to the crankcase 4 with bolts 26 together with the cylindrical cylinder holder 24 connected to the right end thereof, so that the cylinder holder 24 is supported by the crankcase 4 via the swash plate anchor 24. Further, on the inner peripheral surface of the cylinder holder 24, the motor cylinder 17 is
The outer periphery of is rotatably supported.

The swash plate anchor 23 and the cylinder holder 24 are previously connected to each other by bolts 27.

To prevent its axial movement while allowing rotation of the predetermined angle of the trunnion shaft 22, arc-shaped long holes 28 drilled in the swash plate anchor 23, the axis O ₂ of the trunnion shaft 22 centered
The bolt 29 is fixed to one end surface of the trunnion shaft 22 through the through hole (see FIGS. 2 and 18).

The motor swash plate 20 is adapted to be actuated by rotation of the trunnion shaft 22 between an upright position perpendicular to the axis of the motor cylinder 17 and a maximum inclined position inclining at a certain angle. In this state, the motor plungers 19, 19,... Reciprocate with the rotation of the motor cylinder 17 to repeat the expansion and contraction strokes.

In order to improve the followability of the motor plunger 19 to the motor swash plate 20, a coil spring 30 for urging the motor plunger 19 in the extension direction is contracted in the cylinder hole 18.

The pump cylinder 7 and the motor cylinder 17 form an integral cylinder block B, and the output shaft 31 is passed through the center of the cylinder block B. Then, the motor cylinder 1 is attached to the flange 31a integrally formed on the outer periphery of the output shaft 31.
The outer end of 7 is struck, the pump cylinder 7 is spline-fitted 32 to the output shaft 31, and the circlip 34 that abuts the outer end of the pump cylinder 7 via the seat plate 33 is locked to the output shaft 31. The cylinder block B is fixed to the output shaft 31.

The right end of the output shaft 31 is the pump swash plate 10 and pump swash plate holder.
12 and the right side wall of the crankcase 4, and extends between the support cylinder 37 and the pump swash plate holder 12 which are fixed to the outer periphery of the right end by a knock pin 35 and a split cotter 36. A drive gear 39 and a thrust roller bearing 40 for a replenishment pump 38, which will be described later, are sequentially provided from the holder 12 side. The right end of the output shaft 31 is rotatably supported by the crankcase 4 via the support cylinder 37 and the ball bearing 41.

Like the pump swash plate holder 12, the drive gear 39 is spline-fitted to the input cylinder shaft 5 and is rotatably supported by the output shaft 31 via a needle bearing 42.

The left end of the output shaft 31 extends so as to penetrate the motor swash plate 20, the trunnion shaft 22, the swash plate anchor 23, and the left side wall of the crankcase 4. Support tube 45 fixed with split cotter 44
Between the swash plate anchor 23 and the swash plate anchor 23, a retainer 46 and a thrust roller bearing 47 are sequentially provided from the swash plate anchor 23 side. The left end of the output shaft 31 is rotatably supported by the swash plate anchor 23 via the needle bearing 48 and the retainer 46.

Further, an input sprocket 3a of the secondary reduction gear 3 is fixed to the left end of the output shaft 31 outside the crankcase 4 with a bolt 49.

In this way, sprocket 2a to sprocket 3a
Since all the constituent members of the transmission T up to are assembled on the output shaft 31 as one assembly, the transmission T can be attached / detached to / from the crankcase 4 very easily.

The output shaft 31 includes a hemispherical centering body 50 that engages with the inner peripheral surface of the pump swash plate 10 so as to be tiltable in all directions, and a motor swash plate.
A hemispherical aligning body 51 is engaged with the inner peripheral surface of the pump swash plate 10 so as to be tiltable relative to all directions.
In addition, the centering action is given to the motor swash plate 20.

The centering action of each swash plate 10, 20 is strengthened, and the pump swash plate 1
0 and the pump plungers 9, 9 ... group, the motor swash plate 20 and the motor plungers 19, 19 ... group, in order to prevent slippage in the rotational direction between each group, each swash plate 10, 20 has a corresponding plunger 9, Spherical recesses 10a, 20a are formed to engage the 19 spherical ends 9a, 19a, respectively.

A hydraulic closed circuit is formed between the hydraulic pump P and the hydraulic motor M as follows.

In the cylinder block B, between the cylinder holes 8, 8 ... Group of the pump cylinder 7 and the cylinder holes 18, 18 ... Group of the motor cylinder 17, annular inner oil passages arranged concentrically around the output shaft 31. 52 and the outer oil passage 53, the annular partition between the oil passages 52, 53, and the outer peripheral wall of the outer oil passage 53 are radially penetrated. The same number of first valve holes 5 as the cylinder holes 8, 8 ... And 18, 18 ...
4, 54 ... and second valve holes 55, 55 ... and adjacent cylinder holes 8, 8 ...
And a large number of pump ports a, a ... Communicating the first valve holes 54, 54 ... With each other, adjacent cylinder holes 18, 18 ... And the second valve hole 5
Are provided with a large number of motor ports b, b,. The inner and outer oil passages 52, 53 correspond to the low pressure and high pressure oil passages of the present invention.

The inner oil passage 52 includes the cylinder block B and the output shaft 31.
Is formed as an annular groove on each of the opposing circumferential surfaces.

As shown in FIGS. 4 and 5, the outer oil passage 53 has an annular dovetail groove 58 formed in the outer periphery of the cylinder block B and staggered arrangement on both side walls of the dovetail groove 58. It is composed of a plurality of semicircular recesses 59, 59 ... Formed, and the open surfaces of the dovetail groove 58 and the recesses 59, 59 ... Are closed by a sleeve 60 welded to the outer peripheral surface of the cylinder block B. The outer oil passage 53 having such a configuration is advantageous in minimizing the high-pressure volume.

The first and second valve holes 54, 55 are arranged so as to pass through the bottom wall of the recesses 59, 59 in a staggered arrangement, and correspondingly, the cylinder holes 8, 8 of the hydraulic pump P are arranged. Hydraulic pump P
... are out of phase with the cylinder holes 18, 18 ... in the circumferential direction.

By doing this, while increasing the wall thickness of the cylinder block B between the first and second valve holes 54, 55, between the valve holes 54, 55,
The interval along the axial direction of the cylinder block B can be narrowed, which can contribute to downsizing of the cylinder block B.

Also, when high oil pressure is introduced to the outer oil passage 53, the dovetail groove
Even if the both side walls of 58 are expanded and deformed, the deformation rather increases the surface pressure of the fitting portion of the cylinder block B and the sleeve 60, thereby preventing oil leakage from the fitting portion. .

The first valve holes 54, 54 ... have spool-type first distribution valves 61,
61 ... and second spool valves 62, 62 ... are slidably fitted in the second valve holes 55, 55. The first eccentric ring 63 surrounding the first distribution valves 61, 61 ...
However, a second eccentric ring 64 surrounding the second distribution valves 62, 62 ... Is engaged via ball bearings 65, 66, respectively. Distribution valve
The outer ends of 61, 61 ... are the first concentric relationship with the first eccentric ring 63.
The compulsory wheel 67 and the outer ends of the second distributing portions 62, 62 ... Are connected to each other by the second compulsory wheel 68 concentric with the second eccentric wheel 64. The connection structure thereof will be described later.

The first eccentric ring 63 is detachably fixed to the outer circumference of the input cylinder shaft 5 by a headed pin 70 and a clip 71, and as shown in FIG. 6, from the center of the output shaft 31 along the eccentric direction line X _1. It is held at a position eccentric for a predetermined distance ε ₁ . Eccentric direction line X
₁ is set at a position a predetermined angle theta ₁ retard the relative rotation direction R of the pump cylinder 7 to the input cylindrical shaft 5 from the virtual trunnion axis O ₁ of the pump swash plate 10. The angle θ ₁ can be easily adjusted by changing the spline fitting position between the input cylinder shaft 5 and the pump swash plate holder 12.

Thus, when the relative rotation occurs between the input cylinder shaft 5 and the pump cylinder 7, each first distribution valve 61 is moved by the first eccentric ring 63 in the first valve hole 54 so as to have a distance of twice the eccentric amount ε _1. As a stroke, the pump cylinder 7 is reciprocated between a radially inner position and an outer position.

In FIG. 6, the discharge region of the hydraulic pump P is indicated by D, and the suction region is indicated by S. In the discharge region D, the first distribution valve 61 moves from the position N ₁ (hereinafter, referred to as an eccentric neutral position) perpendicular to the eccentric direction line X ₁ to the inside position side, and moves the corresponding pump port a to the outside oil position. Hydraulic oil is pumped from the cylinder hole 8 to the outer oil passage 53 by the pump plunger 9 during the discharge stroke, while being in communication with the passage 53 and not communicating with the inner oil passage 52.

In the suction region S, the first distribution valve 61 is moving from the eccentric neutral position N ₁ to the outer position side so that the corresponding pump port a communicates with the inner oil passage 52 and does not communicate with the outer oil passage 53. , The inner oil passage 52 by the pump plunger 9 during the suction stroke
The hydraulic oil is sucked into the cylinder hole 8 from.

Further, at the eccentric neutral position N ₁ , the first distribution valve 61 makes the corresponding pump port a incommunicable with both oil passages 52 and 53. in this case,
As shown in FIG. 6A, the pump port a of the first distribution valve 61.
The land portion 61a for closing is provided with a predetermined valve closing margin l ₁ only on the outer oil passage 53 side.

In this way, the discharge area D of the hydraulic pump P is retarded by the angle θ ₁ as compared with the case where the eccentric direction line X ₁ is matched with the virtual trunnion axis O ₁ , and the suction area S is discharged.
Wider than is set.

As shown in FIGS. 1, 2 and 8, the second eccentric wheel 64 is provided between the clutch-on position n and the clutch-off position via a support shaft 75 and a pivot shaft 76 parallel to the output shaft 31. They are connected so that they can swing. The support ring 75 is detachably fixed to the outer circumference of the cylinder holder 24 via a plurality of headed pins 77 and clips 78.

The eccentric direction line X ₂ of the second eccentric ring 64 is the trunnion axis line.
Set from the O ₂ to a position by a predetermined angle theta ₂ binary angle in the rotational direction R of the motor cylinder 17, the eccentricity is a clutch-on position n in epsilon _2, made larger than the clutch-off position f in epsilon ₂ epsilon It is ₃ .

Thus, when the motor cylinder 17 rotates when the second eccentric wheel 64 occupies the clutch-on position n, each second distribution valve 62 is rotated.
Is the eccentric amount ε in the second valve hole 55 due to the second eccentric ring 64.
_A stroke twice as long as two strokes is reciprocated between the radially inner position and the outer position of the motor cylinder 17.

In FIG. 9, the expansion region of the hydraulic motor M is indicated by Ex and the contraction region thereof is indicated by Sh. In expansion area Ex, the second distribution valve 62 from the eccentric neutral position N ₂ have moved the inner position, the corresponding motor port b to the normal to the inner oil passage 52 communicates with the outside oil passage 53, High-pressure hydraulic oil is supplied from the outer oil passage 53 to the cylinder hole 18 of the motor plunger 19 during the expansion stroke.

In shrinkage region Sh, the second distributing valves 62 is the eccentric neutral position N ₂ have shifts along the above to the corresponding motor port b in disconnected and outside oil passage 53 communicates with the inside oil passage 52, The working oil is discharged from the cylinder hole 18 of the motor plunger 19 to the inner oil passage 52 during the contraction stroke.

Further the eccentric neutral position N _2, the second distribution valve 62 is in disconnected and Ryoaburaro 52 and 53 the corresponding motor port b. in this case,
As shown in FIG. 9A, the land portion 62a that closes the motor port b of the valve 62 is provided with a predetermined valve closing margin l ₂ only on the outer oil passage 53 side.

In this way, the expansion region Ex of the hydraulic motor M is advanced by an angle θ ₂ compared with the case where the eccentric direction line X ₂ is aligned with the trunnion axis O ₂ , and the contraction region Sh is wider than the expansion region Ex. Is set to.

Further, when the motor cylinder 17 rotates when the second eccentric wheel 64 occupies the clutch-off position f, each second distribution valve 62 is moved by the second eccentric wheel 64 to the second valve hole 55 as shown in FIG.
At a distance of twice the eccentricity ε ₃ as a stroke, the motor cylinder 17 is reciprocated between an inner position and an outer position in the radial direction. At the inner and outer positions thereof, the second distribution valve 62 is connected to the outer oil passage. 53 is opened to the outside of the cylinder block B.

A pair of the pump ports a is provided for one cylinder hole 8 and arranged in a direction perpendicular to the sliding direction of the first distribution valve 61. Also, the motor port b has one cylinder hole.
A pair of 18 is provided side by side in the direction perpendicular to the sliding direction of the second distribution valve 62. In this way, the pump port a
In addition, it is possible to open and close the corresponding ports a and b with a relatively short stroke of each of the distribution valves 61 and 62 while securing a large total passage area of the motor port b.

Referring again to FIG. 8, the second eccentric ring 64 has its pivot shaft 76
An abutting plate 79 is fixed to the peripheral wall on the opposite side with screws 80, and a cam shaft 81 pivotally supported by the crankcase 4 is directed to the abutting plate 79 and to the clutch off position f of the second eccentric wheel 64. Are engaged so that they can be pushed. An operation wire 83 is connected to a clutch lever 82 fixed to the outer end of the cam shaft 81, and the lever 82 is provided between the clutch lever 82 and the crankcase 4.
The return spring 84 is contracted. Further, the second eccentric wheel 64 is biased toward the clutch-on position n side by the set spring 85. The set spring 85 is contracted between the retainer 87 fixed to the outer circumference of the second eccentric ring 64 with a screw 86 and the support ring 75.

Therefore, the second eccentric wheel 64 is normally held in the clutch-on position n by the force of the set spring 85, but when the cam shaft 81 is rotated as shown by the arrow by the pulling operation of the operating wire 83, the clutch-off position f is reached. Is rocked to.

In the above configuration, when the input cylinder shaft 5 of the hydraulic pump P is rotated from the primary reduction gear 2 with the second eccentric wheel 64 held at the clutch-on position n, the pump swash plate 10 discharges to the pump plungers 9, 9,. And the suction stroke are given alternately.

The pump plunger 9 pumps hydraulic oil from the cylinder hole 8 to the outer oil passage 53 while passing through the discharge region D, and pumps hydraulic oil from the inner oil passage 52 to the cylinder hole 8 while passing through the suction region S. Inhale.

The high-pressure hydraulic oil sent to the outer oil passage 53 is supplied to the hydraulic motor M
Cylinder hole of motor plunger 19 in the expansion region Ex
While being supplied to 18, the hydraulic oil is discharged from the cylinder hole 18 to the inner oil passage 52 by the motor plunger 19 existing in the contraction region Sh.

During this time, the reaction torque that the pump cylinder 7 receives from the pump swash plate 10 via the pump plunger 9 in the discharge stroke and the motor plunger 19 in the expansion stroke in the motor cylinder 17
The cylinder block B is rotated by the sum of the reaction torque received from the motor swash plate 20 via the motor and the rotation torque is transmitted from the output shaft 31 to the secondary reduction gear 3.

In this case, the gear ratio of the output shaft 31 to the input cylinder shaft 5 is given by the following equation.

Therefore, if the capacity of the hydraulic motor M is changed to a value of zero, the gear ratio can be changed from 1 to a certain required value. Moreover, since the capacity of the hydraulic motor M is determined by the stroke of the motor plunger 19, the gear ratio is continuously controlled from 1 to a certain value by tilting the motor swash plate 20 from the upright position to a certain tilt position. can do.

By the way, in the hydraulic pump P, since the suction area S is set to be wider than the discharge area D, even if the back pressure of the pump plunger 9 in the suction stroke is much lower than that of the pump plunger 9 in the discharge stroke, the cylinder hole 8 can be effectively increased. As a result, the efficiency of the hydraulic pump P can be improved as a whole even if the discharge area D is somewhat sacrificed.

In order to maximize the efficiency, the suction area S should be 180 °
Is best to

In addition, the discharge region D has an angle θ compared to the case where the eccentric direction line X ₁ of the first eccentric ring 63 is aligned with the virtual trunnion axis O _1.
Since it is retarded by ₁ , the pump plunger 9 receives a large compressive load from the pump swash plate 10 from when the pump plunger 9 contracts a certain amount past the maximum extension point. As a result, the maximum bending moment generated in the pump plunger 9 decreases,
The twisting phenomenon between the pump plunger 9 and the opening edge of the cylinder hole 8 is alleviated, and the friction loss due to the phenomenon is significantly reduced.

On the other hand, in the hydraulic motor M, since the contraction region Sh is set to have a wider angle than the expansion region Ex, the back pressure of the motor plunger 19 during the contraction stroke can be sufficiently reduced, and the expansion region Ex
, The efficiency of the hydraulic motor M can be improved as a whole.

In order to maximize the efficiency, the shrinkage area Sh should be 180 °.
Is best to

Further, since the expansion region Ex is retarded by the angle θ ₂ compared with the case where the eccentric direction line X ₂ of the second eccentric ring 64 is aligned with the trunnion axis O ₂ , the motor plunger 19 is at the most extension point during the expansion stroke. Before reaching, the thrust reaction force of the motor swash plate 20 is released early. As a result, the maximum bending moment generated in the motor plunger 19 is reduced, so that the prying phenomenon between the pump plunger 19 and the peripheral edge of the cylinder hole 18 is alleviated, and the friction loss due to the phenomenon is significantly reduced.

During such operation, if the second eccentric wheel 64 is swung to the clutch-off position f, the second distribution valve 62 causes the high-pressure outer oil passage.
Since 53 is opened outside the cylinder block B, high-pressure hydraulic oil is not supplied to the hydraulic motor M, and the power transmission between the hydraulic pump P and the hydraulic motor M is cut off. That is, a so-called clutch-off state is obtained.

During operation of the hydraulic pump P and the hydraulic motor M, the pump swash plate
10 is from the pump plungers 9,9 ... group and motor swash plate 20
Are subjected to thrust loads in opposite directions from the motor plungers 19, 19 ... Group, but the thrust load received by the pump swash plate 10 is the thrust roller bearing 11, the pump swash plate holder 12, the thrust roller bearing 40, the support cylinder 37 and the cotter 36. The thrust load received by the motor swash plate 20 via the output shaft 31 is also output via the thrust roller bearing 21, the trunnion shaft 22, the swash plate anchor 23, the thrust roller bearing 47, the support cylinder 45 and the cotter 44. It is supported by the shaft 31. Therefore, the above thrust load is
Only a tensile stress is generated in the crankshaft 31, and the crankcase 4 supporting the shaft 31 does not act at all.

As shown in FIGS. 6 and 7, the connecting structure of the first distributing valve 61 and the compulsory wheel 67 is such that the small diameter neck portion 61b formed in the distributing valve 61 is engaged with the neck portion 61b. As described above, the support ring 75 is provided with a circumferentially elongated hole 89, and an enlarged diameter hole 90 is continuously provided at one end of the elongated hole 89 so that the large outer diameter portion of the distribution valve 61 can pass therethrough. It Therefore, by inserting the distribution valve 61 into the expanded diameter hole 90 and aligning the neck portion 61b with the long hole 89, and then rotating the compulsory wheel 67 in the circumferential direction, the neck portion 61b is engaged with the long hole 89. can do. In order to maintain this engaged state, the elastic plug 91 is fitted into at least one of the expanded diameter holes 90.

As shown in FIGS. 11 and 12, the connection structure between the second distribution valve 62 and the compulsory wheel 68 is the same as the above-mentioned first distribution valve 61 and the compulsory wheel.
Since it has the same structure as the connection structure with 67, the same reference numerals are given to the corresponding parts and the detailed description thereof will be omitted.

In FIG. 1, FIG. 2, FIG. 17, and FIG. 8, a gear shift control device 93 for controlling the angle of the motor swash plate 20 is connected to the trunnion shaft 22. This gear change control device 93
Is a sector gear 96 fixed to the other end of the trunnion shaft 22 with a bolt 94 and a pair of knock pins 95, 95, a worm gear 97 meshing with the sector gear 96, and a forward and reverse rotation connecting the drive shaft 98 to the worm gear 97. The worm gear 97 is rotatably supported by bearings 102 and 103 in a gear box 101 fixed to the crankcase 4 with bolts 100. Further, the stator of the electric motor 99 is fixed at a proper position of the crankcase 4.

In the above, the sector gear 96 and the worm gear 97 are
Although the rotation of the drive shaft 98 can be decelerated and transmitted to the trunnion shaft 22, the speed reduction device 106 is configured to be in a locked state when receiving a reverse load from the trunnion shaft 22.

Thus, if the electric motor 99 is rotated forward or backward, the rotation is reduced and transmitted from the worm gear 97 to the sector gear 96, and further transmitted to the trunnion shaft 22, which transmits the rotation in the rising direction of the motor swash plate 20 or It can be rotated in the tilting direction.

Further, when the electric motor 99 is stopped and the motor swash plate 20 is held at an arbitrary angle, the motor swash plate 20 moves to the motor plunger 1
9,19… Receive the moment in the standing or tilting direction from the group,
The moment is transmitted to the sector gear 96 via the trunnion shaft 22.
Cannot transmit the worm gear 97 from the sector gear 96, the two gears 96, 97 exhibit a locked state and do not allow the rotation of the trunnion shaft 22, and therefore, the motor swash plate 20 is in its current position. It is securely held.

In order to restrict the standing position and the tilted position of the motor swash plate 20 by the electric motor 99, the sector gear 96 is provided with an arcuate restriction groove 104 concentric therewith and the restriction groove 104.
The stopper pin 105 slidably engaged with
To be fixed.

Referring again to FIGS. 1 and 2, the output shaft 31 has a main oil passage 108 bored at the center thereof, the inner end of which is stopped, and the main oil passage 108 is provided with an oil filter 109 over substantially the entire length thereof. It is installed.

The open end of the main oil passage 108 communicates with the oil sump 110 at the bottom of the crankcase 4 via the replenishment pump 38, and the replenishment pump 38 is driven by the drive gear 39 splined to the input cylinder shaft 5. Therefore, while the input cylinder shaft 5 is rotating, the oil sump 11
The oil in 0 is fed to the main oil passage 108 by the replenishment pump 38.

The oil sent to the main oil passage 108 is filtered by an oil filter 109, and then a radial replenishment hole 111 formed in the output shaft 31.
And is sent to the inner oil passage 52 via. In this manner, the hydraulic closed circuit between the hydraulic pump P and the hydraulic motor M is replenished with the leaked amount of hydraulic oil.

The replenishment hole 111 is provided with a first check valve 112 for blocking the reverse flow of oil from the inner oil passage 52, and the check valve 112 is closed by a leaf spring 114 surrounding the output shaft 31. It is urged in the valve direction.

Thus, during reverse load operation, that is, during engine braking, the hydraulic motor M acts as a pump and the hydraulic pump P acts as a motor, so that the outer oil passage 53 is at a low pressure and the inner oil passage 52 is at a high pressure. Change from the inner oil passage 52 to the supply hole
The hydraulic oil tries to flow back to 111, but the backflow is blocked by the first check valve 112. Thus, the hydraulic motor M
The reverse load is reliably transmitted from the hydraulic pump P to the hydraulic pump P, and a good engine braking effect is obtained.

The oil sent to the main oil passage 108 is also sent to the lubricating oil passages 117, 118 via the pair of radial left and right orifices 115, 116 provided in the output shaft 31. These lubricating oil passages 117,118
Is formed as an annular groove on the outer periphery of the output shaft 31 so as to face the inner peripheral surfaces of the pump cylinder 9 and the motor cylinder 17.

The oil sent to the lubricating oil passage 117 on the right side is introduced into the input cylinder shaft 5 through the axial oil groove 119 provided in the spline fitting portion 32 of the output shaft 31 with the cylinder block B. In this way, the pump swash plate 10, the pump plunger 9, the thrust roller bearing 11, the needle bearing 42, the seat plate 33, the aligning body 50, etc. in the input cylinder shaft 5 are lubricated.

Further, in order to satisfactorily lubricate the thrust roller bearing 11 and the needle bearing 42, both bearings 11, 4
A small hole 120 communicating with the main oil passage 108 is formed in the output shaft 31 in the vicinity of 2.

The oil that has finished lubricating the needle bearing 42 is then diffused by centrifugal force to lubricate the thrust roller bearing 40.

The oil sent to the lubricating oil passage 118 on the left is the motor cylinder 1
It is introduced into the swash plate anchor 23 and the cylinder holder 24 through an oil groove 121 provided so as to traverse the flange 31a of the output shaft 31 with which the end portion of 7 abuts. Thus, the swash plate anchor 23
Also, the motor swash plate 20 in the cylinder holder 24, the motor plunger 19, the thrust roller bearing 21, the trunnion shaft 2
2. The aligning body 51, the needle bearings 25, 48, etc. are lubricated.

Further, in order to satisfactorily lubricate the needle bearing 48, a small hole 122 communicating with the main oil passage 108 is formed in the output shaft 31 in the vicinity of the bearing 48.

The oil that has finished lubricating the needle bearing 48 is then diffused by centrifugal force to lubricate the thrust roller bearing 47.

Referring to FIGS. 2, 15 and 16, the motor cylinder
17 is adjacent to the motor plunger 19 in the always sliding section 2
A radial oil passage 123 that connects the inner end to the oil groove 121 through the two cylinder holes 18, 18 and an axial oil passage that connects the outer end of the oil passage 123 to the outer oil passage 53. And 124 are drilled.

At this time, the oil passage 123 in the radial direction is machined with a drill having a diameter larger than the thickness of the partition wall between the two cylinder holes 18, 18 in order to obtain the passage cross-sectional area as large as possible. For this reason, the side holes indicated by reference numeral 125 are the two cylinder holes 18,18.
Although it will hit the inner wall of the
Since it is closed by the motor plunger 19 that constantly slides on the cylinder, there is no fear that the hydraulic oil in the cylinder hole 18 will leak through the side hole 125.

A second check valve 113 that prevents the reverse flow of the hydraulic oil from the outer oil passage 53 is interposed in the oil passage 124 in the axial direction. The valve seat 126 that cooperates with the second check valve 113 also functions as a plug that closes the perforation port 124a of the oil passage 124. The second check valve 113 is biased by the spring 127 toward the valve seat 126.

Therefore, during normal load operation in which the outer oil passage 53 has a high pressure, the second check valve 113 maintains the closed state to prevent the hydraulic oil from flowing from the outer oil passage 53 to the oil passage 124 side. Road 5
At the time of engine braking where the pressure is low at 3, the second check valve 113 opens due to the leakage of hydraulic oil from the hydraulic closed circuit. Therefore, the hydraulic oil flows from the main oil passage 108 through the oil groove 121 and the oil passages 123, 124 sequentially to the outside oil. Replenished to road 53.

FIGS. 19 to 21 show another embodiment of the present invention. When the second eccentric wheel 64 is operated to the clutch off position f, the second distribution valve 62 causes the outer oil passage 53 and the inner oil passage 52. It is designed to communicate with each other. This can also cut off power transmission between the hydraulic pump P and the hydraulic motor M. Incidentally, in the figure, the same reference numerals are given to the portions corresponding to the previous embodiment.

C. Effects of the Invention As described above, according to the present invention, the eccentric wheel is supported by the cylinder holder that is formed separately from the casing and rotatably holds the cylinder block, and also supports the swash plate. The anchor is removably fixed to the casing, and the cylinder holder is integrally connected to the swash plate anchor so as to be supported by the casing via the swash plate anchor, so that the same support system is formed. The swash plate and the eccentric ring can be supported by the plate anchor and the cylinder holder, respectively.
Therefore, not only the mutual phase of the trunnion axis of the swash plate and the eccentric direction line of the eccentric wheel, but also the eccentric amount of the eccentric wheel with respect to the cylinder block should be set accurately as desired without being substantially affected by machining and assembly errors. It is possible to obtain a swash plate type hydraulic device with stable characteristics. Moreover, this hydraulic system is equipped with cylinder block, swash plate, eccentric ring, and other main parts.
Since the assembly unit can be assembled together with the swash plate anchor and the cylinder holder as one assembly unit independent from the casing, the assembly unit can be removed and attached to the casing efficiently at one time, and the assembly work of the device can be performed. It can greatly contribute to improvement of maintenance workability such as maintenance and disassembly maintenance.

[Brief description of drawings]

1 to 18 show a first embodiment of the present invention. FIG. 1 is a vertical plan view of a hydrostatic continuously variable transmission provided in a power transmission system of a motorcycle, and FIG. FIG. 1 is a longitudinal rear view, FIG. 3, FIG. 4, and FIG. 5 are III-III line and IV of FIG.
-IV line and VV line sectional drawing, FIG. 6 is VI-VI of FIG.
FIG. 6A is an enlarged sectional view around the first distributing valve when the eccentric neutral position is reached in FIG. 6, and FIG.
VII-VII line sectional view, FIG. 8 is a VIII-VIII line sectional view of FIG. 1, FIG. 9 is a IX-IX line sectional view of FIG. 1 (clutch ON state), and FIG. 9A is FIG. FIG. 10 is an enlarged cross-sectional view around the second distributing valve when the eccentric neutral position is reached, FIG. 10 is an operation diagram of FIG. 9 (clutch-off state), and FIG. 11 is a XI arrow view of FIG.
FIG. 12 is a front view of the second distributing valve, FIGS.
XIII-XIII line and XIV-XIV line sectional drawing of the figure, FIG.
16 is an enlarged view of a part of the figure, FIG. 16 is a sectional view taken along line XVI-XVI in FIG. 15, FIG. 17 is a sectional view taken along line XVII-XVII in FIG. 2, and FIG. 18 is a sectional view taken along the arrow XVIII in FIG. FIGS. 19 to 21 show a second embodiment of the present invention. FIG. 19 is a sectional view corresponding to FIG. 10, FIG. 20 is a front view of the second distributing valve, and FIG. XX in Figure 20
It is a sectional view taken along the line I-XXI. B ... cylinder block, M ... hydraulic motor as a swash plate type hydraulic unit, trunnion axis of the O ₂ ... swash plate 20, X ₂ ... eccentric wheel 64
Eccentric direction line, ε ₂ ... Eccentric amount, 4 ... Crankcase as casing, 18 ... Cylinder hole, 20 ... Swash plate, 22 ... Trunnion shaft, 23 ... Swash plate anchor, 24 ... Cylinder holder, 52
... Inner oil passage as low pressure oil passage, 53 ... Outer oil passage as high pressure oil passage, 62 ... Distribution valve, 64 ... Eccentric ring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takushi Matsuto 1-4-1 Chuo, Wako-shi, Saitama Inside Honda R & D Co., Ltd. (72) Inventor Yoshihiro Nakajima 1-4-1 Chuo, Wako-shi, Saitama Incorporated in Honda R & D Co., Ltd. (56) References Japanese Patent Laid-Open No. Sho 61-153057 (JP, A) Shokai No. 57-57281 (JP, U)

Claims (4)

[Claims] 1. A cylinder block (B) having an annular array of cylinder holes (18) and concentric annular high pressure oil passages (53) and low pressure oil passages (52), and a group of cylinder holes (18) thereof. Plunger (19) group to be slid onto
8) A swash plate (2) that engages the projecting end of the group and reciprocates each plunger (19) as the cylinder block (B) rotates.
0) and radially arranged on the cylinder block (B),
The cylinder block (B) is reciprocated between an outer position and an inner position in the radial direction to move each cylinder hole (18) through the high pressure oil passage (53).
And a group of distribution valves (62) alternately communicating with the low pressure oil passage (52), and an inner peripheral surface of the distribution valve (62) is slidably contacted with an outer end of the group of distribution valves (62) with respect to a rotation center of the cylinder block (B). The eccentric wheel (64) is eccentrically arranged and accommodates in the casing (4) an eccentric wheel (64) that reciprocates each distribution valve (62) with the rotation of the cylinder block (B). 64) is formed separately from the casing (4) and is supported by a cylinder holder (24) that rotatably holds the cylinder block (B), and also supports a swash plate (20). The anchor (23) is detachably fixed to the casing (4), and is attached to the cylinder holder (2).
A swash plate type hydraulic device is characterized in that 4) is integrally connected to the swash plate anchor (23) so as to be supported by the casing (4) through the swash plate anchor (23). 2. The cylinder holder (24) supports the cylinder block (B) at an inner peripheral portion thereof and a support ring (75) of the eccentric wheel (64) at an outer peripheral portion thereof. The swash plate type hydraulic device according to claim 1. 3. The swash plate type hydraulic device according to claim 1, wherein the eccentric ring (64) is supported by the cylinder holder (24) so that the eccentric amount can be adjusted. . 4. The cylinder holder (24) and the swash plate anchor (23) are fastened to the casing (4) by a common bolt (26). The swash plate hydraulic device according to the item 1 or 2.