JP3151574B2 - Hydrostatic clutch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrostatic clutch in which power can be transmitted from a rotary input member to a rotary output member by using static oil pressure.

[0002]

2. Description of the Related Art In such a hydrostatic clutch, a cam surface is formed on one of a rotation input and output member, and a cylinder block is fixed to the other of the rotation input and output members. An even number of plungers reciprocated in exactly the same phase in the first half and the other half by the cam surface with the relative rotation are fitted respectively, and these plungers communicate and shut off hydraulic chambers defined in the cylinder block. Generally, a clutch valve is provided with the clutch valve (see, for example, Japanese Patent Application Laid-Open No. 63-115916).

[0003]

In the above-mentioned conventional hydrostatic clutch, hydraulic oil is supplied from an oil pump in order to supply hydraulic oil leaked from a hydraulic chamber defined in a cylinder block to the hydraulic chamber. The valve chamber and the hydraulic chamber are connected via an orifice, and hydraulic oil is supplied to the low-pressure hydraulic chamber through the orifice.

However, when the hydraulic chamber and the valve chamber are connected via the orifice, it is inevitable that a small amount of hydraulic oil flows from the high-pressure hydraulic chamber to the low-pressure hydraulic chamber via the orifice. As a result, there is a problem that it is difficult to maintain the engaging force of the clutch.

The present invention has been made in view of the above circumstances, and has as its object to smoothly supply hydraulic oil to a hydraulic chamber in order to maintain the engaging force of a clutch.

[0006]

In order to achieve the above-mentioned object, the present invention provides a cam surface formed on one of a rotating input and output member.
And fix the cylinder block to the other of them
However, this cylinder block has a phase of rotation input and output members.
Opposite rotation between half and half by the cam surface with the counter rotation
Each even number of plungers reciprocated in phase
These plungers are used to fit inside the cylinder block.
The hydraulic chambers defined in
Clutch-off type that allows hydraulic oil to be exchanged between
State and the hydraulic chambers are shut off from each other,
A clutch that can be arbitrarily switched to the clutch-on state to lock
A hydrostatic clutch having a latch valve , wherein at least a clutch is provided in an oil passage connecting a hydraulic supply source and a hydraulic chamber.
When the valve is in the clutch-on state that shuts off the hydraulic chambers
A first feature in that a pressure holding means for allowing the hydraulic oil to flow to the hydraulic chamber from the hydraulic pressure source with regulating the outflow of hydraulic fluid to the hydraulic supply source from the hydraulic chamber.

Further, the present invention provides, in addition to the first feature described above,
The clutch valve is provided with a valve element biased radially inward by a valve spring, and the valve element is moved radially outward against the valve spring by centrifugal force due to the rotation of the rotary input member to thereby establish communication between the hydraulic chambers. Blocking is a second feature.

[0008] The present invention provides, in addition to the first feature described above,
A third feature is that the contact portion of the plunger with respect to the cam surface is eccentric in the radial direction of the rotation input / output member from the center axis of the plunger.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show a first embodiment of the present invention. FIG. 1 is a vertical sectional view of a hydrostatic clutch, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and FIG. 1 is a sectional view taken along line 3-3, FIG. 4 is a sectional view corresponding to FIG. 1 and shows a disengaged state of the clutch, and FIG. 5 is a sectional view taken along line 5-5 in FIG.

First, in FIG. 1, a crankshaft 1 of an engine and a main shaft 2 of a transmission are supported on a crankcase 5 via radial bearings 3 and 4 in parallel with each other. The two shafts 1 and 2 are connected via a primary reduction gear 6 and a hydrostatic clutch 7 of the present invention. The primary reduction gear 6 includes a small-diameter gear 8 fixed to the right end of the crankshaft 1.
And a large-diameter gear 9 that can rotate on the main shaft 2. The large-diameter gear 9 forms a rotation input member in the present invention, and the main shaft 2 forms a rotation output member in the present invention.

The clutch 7 has a cylindrical cylinder block 11 spline-coupled to the right end of the main shaft 2 and fixed with a nut 10. Concentric boss 11 ₁
The large-diameter gear 9 is rotatably supported. A thrust bearing 12 is interposed between the large-diameter gear 9 and the inner race of the radial bearing 4.

The cylinder block 11 has an even number (eight in the illustrated example) of cylinder holes 13, 13... Arranged in a ring so as to surround the axis thereof and be parallel to the axis.
They are closed at the right end and open at the left end. Plungers 14, 14 are respectively slidably fitted in these cylinder holes 13, 13,.
Makes the left end face slidably abut against the corrugated cam face 15 formed on the right side face of the large diameter gear 9.

[0014] As apparent from FIG. 2, the cam surface 15 is provided with even number of plungers 14, 14 ... Mountain portion 15 ₁ and the valleys 15 ₂ formed at equal intervals in the pitch of the alternately so that each plunger 14 , 14 ... are engaged alternately the ridges 15 ₁ and valleys 15 _2. The plungers 14, 14... Which slidably contact the cam surface 15 are formed in a spherical shape.

Each of the plungers 14, 14 ... defines a hydraulic chamber 16, 16 ... in a corresponding cylinder hole 13, 13, .... The plungers 14, 14 ... The springs 17, 17 ... biased in the contact direction are accommodated.

At the center of the cylinder block 11, there is provided a bottomed cylindrical valve chamber 18 in which a head of the nut 10 faces and a piston-like clutch valve 19 is slidably fitted. An annular communication path 20 is provided on the outer peripheral surface of the clutch valve 19, and the hydraulic chamber 1 is provided on the inner peripheral surface of the valve chamber 18.
.. (See FIG. 5) and second radial oil passages 21b, 2 respectively connected to six radially extending first oil passages 21a, 21a.
1b (see FIG. 3) are opened. And the eight second
Each of the oil passages 21b, 21b is provided with a check valve 22, 22,... That allows only the flow of hydraulic oil from the communication passage 20 to the valve chamber 18.

The clutch valve 19 is shifted from the clutch-on position N (see FIG. 1) regulated by the stopper ring 23 locked on the inner peripheral surface of the valve chamber 18 to a predetermined distance to the left. At the clutch-on position N, the outer peripheral surface of the clutch valve 19 closes all open ends of the first oil passages 21a, 21a,. In the clutch off position F, the first
The oil passages 21 a are connected to each other via a communication passage 20.

The right end of the crankcase 5 is a side cover 2
4 covered. A push rod 26 capable of pushing the clutch valve 19 to the clutch off position F against a clutch spring 25 contracted in the valve chamber 18 is slidably supported on the side cover 24. operating shaft 27 having a cam 27 ₁ capable of pushing is rotatably supported. An operation lever 28 is fixed to one end of the operation shaft 27, and a clutch lever (both not shown) is connected to the operation lever 28 via a clutch wire. Operation axis 2
The other end of 7 is connected to a return spring 29 for urging the push rod 26 toward the return side.

[0019] In Thus, by operating the clutch lever, not shown, back when rotating the operating shaft 27 against the force of the spring 29, the cam 27 ₁ of the operating shaft 27 is a clutch valve via a push rod 26 19 Can be moved to the clutch off position F. When the clutch lever is released, the operating shaft 27 is rotated in the opposite direction by the force of the return spring 29. It can be returned to the ON position N.

At the center of the main shaft 2 is provided an oil supply passage 32 for guiding lubricating oil discharged from an oil pump 30 driven by the crankshaft 1 via a check valve 31. The oil supply passage 32 is introduced into the oil supply passage 32. The lubricating oil supplied is supplied to the cam surface 15 through an oil hole 33, and
Supplied to the upper gear.

The lubricating oil discharged from the oil pump 30 is also used as a pump for supplying hydraulic oil to the hydraulic chambers 16, 16,. That is, the tip of an oil supply pipe 35 projecting leftward from the center of the clutch valve 19 is slidably fitted in the oil supply passage 32, and the end of the oil supply pipe 35 penetrates the inside of the clutch valve 19 in the radial direction. Connected to the communication passage 20 via two oil passages 36. Oil pump 3
An auxiliary pump 37, which is driven by a manual or small motor as needed, is connected via a check valve 38 to an oil passage connecting the oil supply passage 32 to the oil supply passage 32.

Next, the operation of this embodiment will be described.

When the small-diameter gear 8 drives the large-diameter gear 9 by the rotation of the crankshaft 1, the cam surface 15 which rotates with the large-diameter gear 9 is rotated.
On the other hand, one half of the plungers 14, 14,.
It climb relatively to the mountain portion 15 _1, the other half tries bath in the valleys 15 _2. The plunger 14 to climb relative to the mountain portion 15 ₁ is pressed in a direction to reduce the hydraulic chambers 16, 16 the volume of which corresponds by the reaction force from the cam surface 15.

If the clutch valve 19 occupies the clutch-on position N as shown in FIG.
The first oil passage 2 connected to the hydraulic chambers 16, 16,.
Are closed, and the check valves 22, 22 provided in the second oil passages 21b, 21b are connected to the oil supply passage 32 from the hydraulic chambers 16, 16 via the oil passage 36 and the oil supply pipe 35. Is restricted, the hydraulic chambers 16, 16,... On the side where the volume is reduced are closed. As a result, the hydraulic chamber 1 on the side where the volume is reduced
The plungers 14, 14,... Sliding with the cylinders 6, 16,... Are hydraulically locked, and the plungers 14, 14,.
5, the rotation torque is transmitted from the cylinder block 11 to the main shaft 2 of the transmission. This is the connection state of the clutch 7.

During such power transmission, the plungers 14, 14,... Climbing the cam surface 15 raise the pressure in the corresponding hydraulic chambers 16, 16,.
The hydraulic oil in the hydraulic chambers 16, 16,.
.. Leak through the sliding gap on the outer circumference, and due to this leak, a relative angular displacement is gradually generated between the cam surface 15 and the plungers 14, 14,. However, the cam surface 15
Plungers 14, 14...
7 are pushed to the cam surface 15 side by the resilience of the hydraulic chambers 16 to enlarge the volumes of the corresponding hydraulic chambers 16, 16.
Hydraulic oil is sucked from the oil supply passage 32 connected to the oil passage through the oil supply pipe 35, the oil passage 36, the communication passage 20, and the second oil passages 21b. In this way, the hydraulic chambers 16, 16,.

[0026] This time, the cam surface 15 having alternating crests 15 ₁ and valley portions 15 _2, the plungers 14 and 14
Can be balanced as a whole, so that the side thrust acting on the cylinder block 11 can be avoided. Moreover,
Since the cylinder block 11 is directly fixed to the main shaft 2, the reaction force applied to the plunger 14 from the cam surface during power transmission acts on the main shaft 2 via the cylinder block 11 as a tensile load. Can be avoided.

Next, when the clutch valve 19 is shifted to the clutch off position F as shown in FIG.
6, 16 ... are the first oil passages 21a, 21a ... and the connecting passage 20.
Are connected to each other through the pressure chambers, and correspond to the plungers 14, 14,... Trying to descend the cam surface 15 from the high pressure side hydraulic chambers 16, 16,. The low pressure side hydraulic chambers 16, 16 ...
Hydraulic fluid flows to the plungers 14, 14
... smoothly reciprocate while sliding on the cam surface 15, so that transmission of rotational torque from the large-diameter gear 9 to the cylinder block 11 is interrupted. This is the disengaged state of the clutch 7.

When the clutch valve 19 is in the clutch on position N
In the process of shifting between the clutch off position F and the communication path 20, the degree of communication between the communication path 20 and the first oil paths 21a, 21a is adjusted appropriately, so that the plungers 14, 14,. An appropriate hydraulic pressure is generated in the corresponding hydraulic chambers 16, 16, and a part of the rotational torque of the large-diameter gear 9 is transmitted to the cylinder block 11. This is the half-clutch state of the clutch 7.

When it is necessary to push the engine due to a failure of the engine starting system such as a starter motor, if the hydraulic oil inside the clutch 7 is removed, the clutch 7 becomes disengageable and starts the engine. Can not do. In such a case, hydraulic oil is supplied to the inside of the clutch 7 by the auxiliary pump 37 so that the clutch 7
Function can be restored and the engine can be started.

FIGS. 6 and 7 show a second embodiment of the present invention. FIG. 6 is a diagram showing a connected state of the clutch, and FIG. 7 is a diagram showing a disconnected state of the clutch.

The clutch 7 of the second embodiment includes a valve chamber 18 formed inside the cylinder block 11 and each hydraulic chamber 1
Are connected to the first oil passages 21a, 21a,.
.. Having a ball pressed against a valve seat by a spring having a predetermined set load. The relief valves 39, 39 are opened by a predetermined pressure to allow the hydraulic oil from the hydraulic chambers 16, 16 to flow out to the valve chamber 18, and the hydraulic oil from the valve chamber 18 to the hydraulic chambers 16, 16,. Regulate the inflow of water.

The communication passage 20 formed on the outer periphery of the cylinder block 11 is formed to be wider in the axial direction than that of the first embodiment, and this communication passage 20 is formed in the clutch 7 shown in FIG.
Are connected only to the first oil passages 21a, 21a,... When the clutch 7 shown in FIG.
, and the second oil passages 21b, 21b,.

When a dog-type transmission is employed, the gears can be smoothly engaged by transmitting an appropriate torque via the clutch 7 even when the clutch 7 is disengaged. . The clutch 7 of the second embodiment functions effectively when used in combination with the dog type transmission.

That is, when the clutch 7 shown in FIG.
The hydraulic oil pushed out from the high-pressure side hydraulic chambers 16, 16 ... is supplied to the relief valves 3 provided in the first oil passages 21a, 21a ...
9, 39 ... are opened and flow out into the communication passage 20, where the relief valves 39, 39 provided in the first oil passages 21a, 21a ...
, Are passed through check valves 22, 22 provided in the second oil passages 21b, 21b,.
16 ... At this time, the high pressure side hydraulic chambers 16 and 1
6 generate a residual pressure due to the set load of the relief valves 39, 39, so that the plungers 14, 14,.
Is pressed against the cam surface 15 and the clutch 7 transmits a slight rotational torque to the main shaft 2. Thus, even when the clutch 7 is disengaged, a slight rotation torque is transmitted, whereby the gears of the transmission can be smoothly engaged.

It should be noted that when the clutch 7 shown in FIG.
In any case when the clutch 7 is disengaged, when the pressure in the hydraulic chambers 16 becomes lower than the pressure in the oil supply passage 32, the check valves 22 in the second oil passages 21b, 21b.
Are opened and hydraulic oil is supplied to the hydraulic chambers 16, 16,. When the clutch 7 is engaged, the relief valves 39, 3
9 are closed by the clutch valve 19, so that there is no inconvenience even if the relief valves 39 are opened.

FIGS. 8 to 10 show a third embodiment of the present invention. FIG. 8 is a view showing a connected state of the clutch, FIG. 9 is a sectional view taken along line 9-9 of FIG. 8, and FIG. 10 is a sectional view taken along line 10-10 of FIG.

The clutch 7 of the third embodiment has a cylinder
Block 11 structure and checks provided inside
The structure of the valve 41 is characteristic. That is, cylinder blow
11 is a cylinder having cylinder holes 13
A check made of an annular leaf spring is attached to the end face of the block body 40.
The oil passage forming block 42 is overlapped via the shutoff valve 41,
Further, the cover plate 43 is superimposed on the outside.
And a structure integrally connected by eight bolts 44. oil
The first oil passages 21a, 21
1a... And the second oil passages 21b, 21b.
The first oil passages 21a, 21a,.
The passages 21b, 21b...₁, 42 ₁By phase
Communicate with each other. On the outer circumference of the check valve 41, eight U-shaped
Valve element 41₁, 41₁… Formed by punching
Valve element 41₁, 41₁… Is the valve hole 4 due to its own elasticity.
2₁, 42₁Are closed so as to close the first oil passages 21a, 21a.
It is urged to be in close contact with the bottom of ...

Thus, according to the third embodiment, the same functions and effects as those of the first embodiment can be obtained. That is, in the engaged state of the clutch 7 shown in FIG. 8, the valve bodies 41 ₁ , 41 ₁ ... Of the check valves 41 corresponding to the hydraulic chambers 16 on the high pressure side close the valve holes 42 ₁ , 42 ₁ . .. Are held in a hydraulically locked state, and the valve bodies 41 ₁ , 41 ₁ ... Are separated from the valve holes 42 ₁ , 42 ₁ . Thus, the working oil can be supplied. Moreover, according to the present embodiment, the check valve 41 composed of one leaf spring corresponds to the eight second oil passages 21b, 21b,.
Since it can have the function of individual check valve,
The number of parts can be reduced and the structure can be simplified.

FIGS. 11 to 13 show a fourth embodiment of the present invention, and FIG. 11 is a view showing a connected state of a clutch.
2 is a sectional view taken along line 12-12 of FIG. 11, and FIG.
It is a 3 part enlarged view.

The clutch 7 according to the fourth embodiment has a cam surface formed on the large-diameter gear 9 for driving the plungers 14, 14,... And a check valve 41 provided inside the cylinder block 11. Has features. That is, the cam surface 45 formed on the large-diameter gear 9 is formed of an inclined surface that functions as a swash plate inclined at a predetermined angle with respect to the main shaft 2. When the large-diameter gear 9 and the cylinder block 11 rotate relatively,
The plungers 14, 14,... Climb the cam surface 45 in a range of 180 °, which is half of one rotation of the cylinder block 11, and descend the cam surface 45 in a range of 180 °, the other half.

The cylinder block 11 includes a first oil passage 21
a, 21a... are radially bored, and an oil passage forming block 47, which radially bores the second oil passages 21b, 21b. And a structure in which the bolts 44 are overlapped with each other and integrally connected by eight bolts 44. Check valve 41
Eight U-shaped valve elements 4 formed by punching on the outer circumference of
1 _1, 41 ₁ ... occludes valve hole 47 _1, 47 ₁ ... a, which is biased to form an oil passage formed block 47 by its own elasticity.

According to the fourth embodiment, the valve body 4 of the check valve 41 corresponding to the hydraulic chambers 16, 16,.
1 _1, 41 ₁ ... is as shown by a chain line in FIG. 13 the valve hole 4
7 ₁ , 47 _1, ...
.. can be supplied through the b, 21b. At this time, the valve elements 41 ₁ , 41 of the check valve 41
_{For 1} ... tip of the first oil passage 21a, in contact with the deflection amount to the stepped portion formed in 21a ... is restricted, the valve element 41 _1,
41 ₁ ... can be ensured in durability. Moreover, since the cylinder block 11 is composed of two members, the cylinder block main body 46 and the oil passage forming block 47, the number of parts can be further reduced as compared with the third embodiment.

FIG. 14 is a sectional view of a clutch showing a fifth embodiment of the present invention.

The clutch 7 of the fifth embodiment has a cylinder block 11 integrally formed at the tip of the crankshaft 1 as a rotation input member. It is rotatably supported on the outer periphery via a needle bearing 48.

The hydraulic chambers 16, 16,...
Are connected via oil passages 21a, 21a, and second oil passages 21b, 21b, and only the inflow of hydraulic oil from the oil supply passage 32 to the hydraulic chambers 16, 16,. Are provided. First
The oil passages 21a, 21a and the second oil passages 21b, 21b are connected to the connection oil passages 49, 4 extending in the axial direction of the cylinder block 11.
9 are provided, and a clutch valve 19 is provided at an intermediate portion between the connecting oil passages 49. Clutch valve 19
Are formed in the radial direction of the cylinder block 11 and intersect with the connecting oil passages 49, 49.
Are provided in the respective guide holes 50, 50.
Are slidably fitted to the valve bodies 52, 52, urged inward in the radial direction. Grooves 52 ₁ , 52 ₁ are formed on the outer periphery of the valve bodies 52, 52... When the valve bodies 52, 52.
2 _1, 52 ₁ ... each connecting oil path 49, 49 ... lateral communicates a result, the valve body 52, 52 each connecting oil path before when moving radially outward position against the valve springs 51, 51 ... 49,
49 are shut off.

While the crankshaft 1 is rotating at a low rotational speed, the resilient forces of the valve springs 51, 51 keep the valve bodies 52, 52. .. And the low pressure side oil chamber are connected oil passages 49, 4
.., The grooves 52 ₁ , 52 _{1 of} the valve bodies 52, 52... And the first oil passages 21 a, 21 a, and the plungers 14, 14.
Can slide. As a result, the plunger 14,
The swash plate type cam surface 45 formed on the large diameter gear 9 from 14.
The transmission of the rotational torque to the clutch 7 is not performed, and the clutch 7 is held in the disconnected state.

When the number of revolutions of the crankshaft 1 increases, the valve bodies 52, 52 move to the radially outer position against the valve springs 51, 51 by centrifugal force and close the connecting oil passages 49, 49. , And the hydraulic oil flows out of the high pressure side hydraulic chambers 16, 16... And the second oil passages 21 b, 21.
are blocked by the check valves 38, 38,... and the plungers 14, 14,... corresponding to the hydraulic chambers 16, 16,. As a result, the plungers 14, 14
, The rotational torque of the cam surface 45 is transmitted from the cylinder block 11 and the clutch 7 is engaged.

When the clutch 7 is in the engaged state, the leakage of hydraulic oil flows into the low-pressure side hydraulic chambers 16 through check valves 38 provided in the second oil passages 21b. Replenished.

Incidentally, as in the fifth embodiment, the crankshaft 1
If the clutch 7 is provided, the rotational speed of the crankshaft 1 is higher than that of the main shaft 2, so that the torque load on the clutch 7 is reduced by that much, and the clutch 7 can be further downsized.

FIGS. 15 and 16 show a sixth embodiment of the present invention. FIG. 15 is a sectional view of a clutch, and FIG.
FIG. 16 is a sectional view taken along line 16-16 of FIG.

In the clutch 7 of the sixth embodiment, the cam surface 15 having the waveform of the clutch 7 of the first embodiment is inclined by an angle θ from a plane perpendicular to the main shaft 2. When the cam surface 15 is inclined in this manner, the point O, which is the tip of the plungers 14, 14... Formed in a spherical shape, does not come into contact with the cam surface 15, and the cam at the point P separated from the point O by a distance δ. It contacts the surface 15. Therefore, when the cam surface 15 and the cylinder block 11 rotate relatively, the plungers 14,
14 rotate within the cylinder holes 13, 13 due to the frictional force that the point P receives from the cam surface 15, thereby preventing uneven wear of the distal ends of the plungers 14, 14,. FIG. 17 shows a modification of the fourth embodiment.

[0052] This modification is provided with a swing freely supported slipper 53 to the spherical portion 14 ₁ formed at the tip portion of the plunger 14, the spherical portion 14 ₁ of the front end surface and the slipper 5
An oil sump 54 is formed between the oil sump 54 and the inner surface of the fuel cell 3. The hydraulic chamber 16 is provided with a high-pressure oil passage 14 penetrating the inside of the plunger 14.
Communicates with an oil reservoir 54 via a _2, further oil reservoir 54 is a swash plate cam surface 45 through the oil hole 53 ₁ through the slipper 53
Communicate with

Thus, according to this modification, the slippers 5
3 and the cam surface 45 are in surface contact, so that not only the surface pressure on the sliding surface can be reduced, but also the operating oil supplied from the high pressure side hydraulic chamber 16 is supplied to the high pressure oil passage 14 ₂ , the oil sump 54 and durability is improved because lubricates the sliding surfaces of the slipper 53 and cam surface 45 through the oil hole 53 _1.

FIG. 18 shows another modification of the fourth embodiment.

[0055] This modification, the flange 53 ₂ formed on the tip of the slipper 53, to guide the flange 53 ₂ is engaged with the annular guide rail 55 formed on the cam surface 45 so as to surround the spindle 2 It has become. Therefore,
The plunger 14 corresponding to the low-pressure side hydraulic chamber 16 is forcibly pulled out of the cylinder hole 13 via the slipper 53 engaging with the guide rail 55, whereby the slipper 53
Can be avoided, and the occurrence of a tapping sound can be prevented. Also, since the forming pressure pockets 53 ₃ communicating with the oil hole 53 ₁ in the tip of the slipper 53, it is possible to further improve the durability by forming an oil film on the sliding surface of the cam surface 45 and the slipper 53.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various small design changes can be made.

For example, in the embodiment, the operation of the clutch lever is transmitted to the clutch valve 19 via the clutch wire, but the clutch valve 19 is operated via the hydraulic pressure generated in the master cylinder connected to the clutch lever. Is also good.

[0058]

As described above, according to the first aspect of the present invention, the outflow of hydraulic oil from the hydraulic chamber to the hydraulic supply source is restricted and the inflow of hydraulic oil from the hydraulic supply source to the hydraulic chamber is permitted. Pressure holding means to reduce the clutch
In down state, the leakage amount of the hydraulic oil from the plunger sliding portion, not only can be replenished smoothly from the hydraulic source to the hydraulic chamber via a pressure maintaining means, a plunger to climb the cams surfaces firmly And the clutch engagement force can be sufficiently secured . Also especially plastic
There are even numbers of jars, with diametrically opposite phases in one half and the other half
It is reciprocated and the clutch valve is in the clutch off state
, The hydraulic chambers communicate with each other and operate between them
Discharge from each plunger because oil transfer is possible
It is no longer necessary to actively drain the hydraulic fluid
This simplifies the oil passage structure and reduces the oil spillage.
No need for a large reserve tank to accept
Energy loss can be suppressed as much as possible.

According to the second feature of the present invention, since the clutch valve has the valve element urged radially inward by the valve spring, the rotational speed of the rotary input member increases, and the centrifugal force is applied to the valve element. , The valve body can be moved radially outward against the valve spring to automatically engage the clutch.

According to the third aspect of the present invention, since the contact portion of the plunger with respect to the cam surface is eccentric in the radial direction of the rotation input / output member from the center axis of the plunger, the frictional force received from the cam surface. By rotating the plunger around the center axis, uneven wear of the plunger can be prevented.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a hydrostatic clutch (in a connected state) according to a first embodiment of the present invention.

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

FIG. 3A is a sectional view taken along line 3-3 of FIG. 1, FIG.
(B) is an enlarged view of a portion B in FIG. 3 (A).

FIG. 4 is a sectional view corresponding to FIG. 1, showing a disengaged state of the clutch.

FIG. 5 is a sectional view taken along line 5-5 of FIG. 4;

FIG. 6 is a longitudinal plan view of a hydrostatic clutch (in a connected state) according to a second embodiment of the present invention.

FIG. 7 is a sectional view corresponding to FIG. 6 and showing a disengaged state of the clutch.

FIG. 8 is a vertical sectional view of a hydrostatic clutch (in a connected state) according to a third embodiment of the present invention.

9 is a sectional view taken along line 9-9 in FIG.

FIG. 10 is a sectional view taken along line 10-10 of FIG. 8;

FIG. 11 is a longitudinal plan view of a hydrostatic clutch (connected state) according to a fourth embodiment of the present invention.

FIG. 12 is a sectional view taken along line 12-12 of FIG. 11;

FIG. 13 is an enlarged view of part 13 of FIG.

FIG. 14 is a longitudinal sectional plan view of a hydrostatic clutch according to a fifth embodiment of the present invention.

FIG. 15 is a vertical sectional view of a hydrostatic clutch according to a sixth embodiment of the present invention.

16 is a sectional view taken along line 16-16 of FIG.

FIG. 17 is a diagram showing a modification of the fourth embodiment.

FIG. 18 is a diagram showing another modification of the fourth embodiment.

[Explanation of symbols]

 Reference Signs List 1 crankshaft (rotation input member) 2 main shaft (rotation output member) 8 small diameter gear (rotation output member) 9 large diameter gear (rotation input member) 11 cylinder block 14 plunger 15 cam surface 16 hydraulic chamber 19 clutch valve 21b second oil Road (oil passage) 22 Check valve (pressure holding means) 30 Oil pump (hydraulic supply source) 37 Auxiliary pump (hydraulic supply source) 41 Check valve (pressure holding means) 45 Cam surface 51 Valve spring 52 Valve body

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Naoki Inoue 1-4-1, Chuo, Wako, Saitama Prefecture Inside Honda R & D Co., Ltd. (56) References JP-A-3-20123 (JP, A) JP-A Heisei 3-20122 (JP, A) JP-A-47-43844 (JP, A) JP-A-63-115916 (JP, A) JP-A-49-43648 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16D 31/02

Claims (3)

(57) [Claims] A cam surface (15, 45) is formed on one of the rotation input / output members (1, 2, 8, 9), and a cylinder block (11) is fixed to the other of the cam surfaces. (11) includes rotation input and output members (1,
With the relative rotation of (2,8,9), the cam surface (15,4)
5) Fit the even number of plungers (14) which are reciprocated in exactly the opposite phases in the first half and the other half, respectively.
The cylinder block (1) is set by these plungers (14).
Plurality of hydraulic chambers made picture, respectively (16) each other is communicated to allow transfer of the hydraulic fluid between its mutually 1) the
The clutch off state and the hydraulic chamber (16) are cut off from each other.
To lock each plunger (14) hydraulically
A hydrostatic clutch having optionally switchable clutch valve (19) into a down state, the oil passage connecting the hydraulic pressure source (30, 37) and the hydraulic chamber and (16) (21b) is , At least a clutch valve (19)
Is in the clutch-on state, which shuts off the hydraulic chambers (16).
Hydraulic supply source from the hydraulic chamber (16) in Rutoki (30, 37)
To the hydraulic oil supply (30,
37. A hydrostatic clutch, comprising pressure holding means (22, 41) for permitting the flow of hydraulic oil from the pressure chamber (37) to the hydraulic chamber (16). 2. A clutch valve (19) comprising a valve element (52) urged inward in a radial direction by a valve spring (51), and the valve element (52) is formed by centrifugal force generated by rotation of the rotary input member (1). The hydrostatic clutch according to claim 1, characterized in that the clutch is moved radially outward against the valve spring (51) to cut off the communication between the hydraulic chambers (16). 3. A contact portion of the plunger (14) with respect to the cam surface (15) is eccentric in the radial direction of the rotation input / output member (1, 2, 8, 9) from the center axis of the plunger (14). The hydrostatic clutch according to claim 1, wherein: