JP2601909Y2 - Hydraulic power transmission coupling - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic power transmission coupling used for distributing driving force of a vehicle.

[0002]

2. Description of the Related Art As a conventional hydraulic power transmission coupling, the present applicant has proposed, for example, the one shown in FIG. The hydraulic power transmission joint is provided between input and output shafts that are rotatable relative to each other and connected to the one shaft.
A housing 103 having a cam surface 102 having one or more peaks; a rotor 105 connected to the other shaft 101 and having a plurality of plunger chambers 104; The cam surface 102 is housed so as to be reciprocally movable under the pressure of the return spring 106, and the cam surface 102
A plurality of plungers 107 that are driven by; a suction hole 108 formed in the head of the plunger 107
A one-way valve 109 serving as a suction valve housed inside the plunger 107; and the plunger chamber 104 formed in the rotor 105.
And a flow resistance generating means 111 formed at an outlet of the high-pressure chamber 110.

[0003] This hydraulic power transmission joint is composed of a housing 1
The accumulator piston 112 rotates together with the accumulator piston 03. The accumulator piston 112 moves according to the internal pressure and absorbs the thermal expansion of the sealed oil. A return spring 114 is interposed between the accumulator piston 112 and the retainer 113, and the accumulator piston 112
An oil seal 115 is interposed between the oil seal 115 and the rotor 105.

This hydraulic power transmission coupling is applied between a transmission for transmitting the engine driving force of a vehicle and a propeller shaft, or between a propeller shaft and a final drive unit, and has a rotational speed substantially equal to that of the engine.
It rotates at high speed at 000-8000 rpm. For this reason,
The oil inside the housing 103 generates pressure due to centrifugal force and tends to expand the accumulator piston 112 outward. In order to prevent the movement of the accumulator piston 112, it is necessary to strengthen the return spring 114 of the accumulator piston 112.

[0005]

In such a conventional hydraulic power transmission joint, when the preload of the accumulator piston is set high in order to prevent the influence of the centrifugal force at the time of high rotation use. , The oil easily leaks from the oil seal due to the internal pressure, and the wear of the lip part progresses,
The durability deteriorates.

Also, the return spring is large and heavy, and the resulting force is also strong. Therefore, it is necessary to design each part little by little, and as a result, it becomes large, heavy and expensive. If the return spring of the accumulator piston is weakened to avoid the above-mentioned problem, when expanding outside the accumulator piston at high speed, air or water is sucked from the oil seal,
This can cause joint failure.

Further, the oil sticks to the outer diameter side of the housing and the number of bubbles increases near the inner diameter side, so that the oil sucked from the oil becomes incompressible and the characteristics of the joint are not exhibited. The present invention has been made in view of such conventional problems, and aims at preventing oil leakage from an oil seal, improving the durability of the oil seal, and reducing the size, weight, and cost. It is another object of the present invention to provide a hydraulic power transmission joint that does not suck air or water and does not generate air bubbles.

[0008]

In order to achieve the above object, the present invention is provided between input / output shafts which can rotate relative to each other.
In a hydraulic power transmission joint for flowing an amount of fluid according to a rotational speed difference between both shafts and controlling a transmission torque between the input and output shafts by a flow resistance of the fluid, a first power transmission joint connected to one of the input and output shafts An accumulator chamber for accommodating foam rubber for absorbing thermal expansion of oil is formed between a hollow portion of the rotating member and an outer peripheral portion of a nut screwed into one of the input / output shafts.

Further, the present invention is provided between the input and output shafts which are relatively rotatable, and allows the fluid of an amount corresponding to the rotational speed difference between the two shafts to flow, thereby reducing the transmission torque between the input and output shafts by the flow resistance of the fluid. In the hydraulic power transmission coupling to be controlled, an annular accumulator chamber is formed between a hollow portion of the first rotating member connected to one of the input / output shafts and a nut screwed into one of the input / output shafts, The accumulator chamber contains an accumulator piston and a preload spring that presses the accumulator piston.

Further, the present invention is provided between an input and output shaft that is rotatable relative to each other, and allows the fluid to flow in an amount corresponding to the rotational speed difference between the two shafts. In the hydraulic power transmission coupling to be controlled, an annular accumulator chamber is formed between a hollow portion of the first rotating member connected to one of the input / output shafts and a nut screwed into one of the input / output shafts, An accumulator chamber is provided with an accumulator piston, an air chamber is formed outside the accumulator piston, and a closing member for sealing the air chamber is provided.

[0011]

SUMMARY OF] According to the present invention a hydraulic power transmission joint having a configuration, it is possible to prevent the influence of centrifugal force during high rotation using the joint hand, can suppress the preload low Therefore, oil leakage from the oil seal can be prevented, and the durability of the oil seal can be improved.

Further, since the preload can be kept low, unnecessary strength is not required for each part, and miniaturization is achieved.
Weight reduction and cost reduction can be achieved. In addition, since there is no place where the internal volume is increased due to the centrifugal force, suction of air or water is eliminated, and problems with the joint can be avoided. Further, since the internal volume does not change due to the centrifugal force, no bubbles are generated, and the joint can exhibit predetermined characteristics.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are views showing an embodiment of the present invention. First, the configuration will be described. In FIGS. 1 and 2, reference numeral 1 denotes a case such as a transfer device. One end of an input shaft 3 is rotatably supported on the case 1 via a bearing 2. A male spline portion 4 is formed on the input shaft 3 and a screw portion 5 is formed.

Reference numeral 6 denotes a rotor shaft (first rotating member) of a joint 7 connected to the input shaft 3, and a hollow portion 8 is formed in the rotor shaft 6. The hollow portion 8 has a step 9
And a female spline portion 11 that fits into the spline portion 4 of the input shaft 3 is formed in the small diameter portion 10 on the right side of the step portion 9. The rotor shaft 6 and the input shaft 3 are spline-fitted by spline portions 11 and 4, and a nut 13 having a hollow portion 12 is screwed into the screw portion 5.

The cylindrical surface of the outer diameter portion 14 of the rotor shaft 6 is precision-finished, and an oil seal 15 is interposed between the outer diameter portion 14 and the case 1. Reference numeral 16 denotes a thrust block connected to an output shaft (not shown). The thrust block 16 is integrally connected to a housing 18 having a cam surface 17 formed long in the axial direction by welding. It constitutes a rotating member.

The thrust block 16 is formed with a flat portion 19, a spigot portion 20, and a bolt hole 21. A plurality of plunger chambers 22 are formed in the rotor shaft 6 in the radial direction, and a plurality of plungers 23 are slidably housed in the plunger chamber 22 via a return spring 24.

A suction hole 25 is formed in the head of the plunger 23, and a one-way valve 26 as a suction valve is housed inside the plunger 23. The one-way valve 26 is pressed by a spring 28 provided in a retainer 27 and seats in the suction hole 25. The return spring 24 is interposed between the retainer 27 and the bottom of the plunger chamber 22, and the retainer 27 is pressed into the plunger 23 by the return spring 24.

An orifice 29 is formed in the one-way valve 26 as flow resistance generating means, and oil sucked into the suction hole 25 is supplied to the retainer 27 by the plunger chamber 2.
An opening 30 returning to 2 is formed. A cover 31 has a function as a disc spring. The cover 31 is fixed to an outer peripheral groove 32 of the housing 18 and applies a preload to the rotor shaft 6. The rotor shaft 6 is pressed toward the thrust block 16 by the cover 31 and is pressed so that the play becomes zero.

An oil seal 33 is interposed between the cover 31 and the rotor shaft 6, and an O-ring 34 is interposed between the cover 31 and the housing 18. A bearing 35 and an oil seal 36 are interposed between the thrust block 16 and the rotor shaft 6, respectively. An accumulator chamber 37 is formed between the hollow portion 8 of the rotor shaft 6 and the outer peripheral portion of the nut 13, and a foam rubber 38 is housed in the accumulator chamber 37.

The nuts 13 on both sides of the accumulator chamber 37
O-rings 39 and 40 are interposed on the outer periphery of
We try to prevent oil leaks. Reference numeral 41 denotes an oil passage formed in the rotor shaft 6, and the joint 7 is connected via the oil passage 41.
And the accumulator chamber 37 communicate with each other. Oilway 4
1 is the accumulator chamber 37 even if the nut 13 moves a little.
Are provided so as not to protrude from the O-rings 39 and 40 on both sides. Reference numeral 42 denotes a snap ring provided on the inner periphery of the rotor shaft 6, and the snap ring 42 prevents the nut 13 from coming off.

As described above, by providing the accumulator chamber 37 near the axis of the joint 7, the influence of the centrifugal force due to the rotation of the joint 7 is minimized.
Here, the effect of the hydraulic pressure due to the centrifugal force is expressed by the following equation.

[0022]

(Equation 1)

[0023] When R ₂ ^2> R ₁ ^2, since Parufaomega ² R ₂ ² becomes, the force P is proportional to the square of the accumulator outdoor diameter, if the accumulator outdoor diameter and 1/2, the force P is It is equivalent to 1/4. That is, even if the force required for the preload is small, the same effect can be obtained.

Next, the operation will be described. In this embodiment, the accumulator chamber 37 is formed between the hollow portion 8 of the rotor shaft 6 and the outer peripheral portion of the nut 13 screwed into the input shaft 3, and the foam rubber 38 is stored in the accumulator chamber 37. , Can be prevented from being affected by the centrifugal force when the joint 7 is used at high rotation.

That is, the accumulator chamber 37 is connected to the joint 7
The effect of the centrifugal force, which is provided near the center of the shaft, can be minimized. For this reason, unlike the related art, it is not necessary to set the preload of the accumulator piston high, and it is possible to prevent oil leakage from the oil seal and improve the durability of the oil seal.

Further, it is not necessary to set the preload of the accumulator piston high, and the accumulator piston is not required, so that unnecessary strength is not required for each part.
The size, weight, and cost can be reduced. In addition, since there is no place where the internal volume is increased due to the centrifugal force, the suction of air or water is eliminated, and the problem of the joint 7 can be avoided.

Furthermore, since there is no change in the internal volume due to the centrifugal force, no bubbles are generated, and the joint 7 can exhibit predetermined characteristics. Next, FIGS. 3 to 5 show the second embodiment of the present invention.
It is a figure showing an example. The joint according to the present embodiment has an inertial valve and is for a vehicle with an ABS.

When the function of the joint is added to the vehicle with the ABS, if the accumulator piston is provided on the outer diameter portion of the rotor shaft, the joint becomes longer, so that the eccentricity becomes larger and the swing of the propeller shaft also becomes larger. As a result, vibration of the vehicle is caused. In addition, it is difficult to make the dimensions of the inertial valve large, and it is easily affected by a slight change in conditions, and it is difficult to make the inertial valve highly reliable.

In order to solve such a problem, in the present embodiment, the accumulator piston is provided inside the joint. 3 and FIG.
Reference numeral 1 denotes a rotor shaft which is spline-engaged with the input shaft 52. A plunger chamber 53 is formed in the rotor shaft 51 in a radial direction, and a plurality of plungers 54 have a return spring 55 in the plunger chamber 53. It is slidably housed through.

Reference numeral 56 denotes a one-way valve. The one-way valve 56 is pressed by a return spring 55 and seats inside the plunger 54 in which a suction hole 57 is opened. As shown in FIG. 5, the one-way valve 56 includes an orifice 58 as a flow resistance generating means, and a suction hole 57.
Notch 5 for returning oil sucked into the plunger chamber 53
9.

A high pressure chamber 60 is provided at the bottom of the plunger chamber 53.
Are formed, and an oil hole 61 communicating with the high-pressure chamber 60 is formed in the rotor shaft 51. The oil hole 61 is normally closed by the inertia valve 62 and is released by the movement of the inertia valve 62. The inertia valve 62 and the rotor shaft 51 are connected by a leaf spring 63, and when the inertia valve 62 moves rightward in FIG.
0 is released and the joint 64 has free characteristics.

Numeral 65 is a nut screwed into a screw portion 66 of the input shaft 52. An annular accumulator chamber 68 is formed between the nut 65 and a hollow portion 67 of the rotor shaft 51. An accumulator piston 69 is slidably housed. Reference numeral 70 denotes a communication hole formed in the rotor shaft 51. One end of the communication hole 70 opens to the accumulator chamber 68, and the other end of the communication hole 70 opens to an oil passage 71 formed in the inertia valve 62.
Communicates with the accumulator chamber 68 through the communication hole 70.

The nut 65 is provided with a retainer plate 72, and a preload spring 73 is interposed between the retainer plate 72 and the accumulator piston 69. The snap ring 74 is fixed to the nut 65 in contact with the retainer plate 72. The nut 65 has a square or hexagonal hole 75 for nut rotation. In addition,
76 is an oil seal, and 77 and 78 are O-rings. 79 is a housing.

When the temperature of the oil inside the joint rises due to the operation of the joint and thermal expansion occurs, the accumulator piston 69
Moves leftward in FIG. 3 against the preload spring 73 to absorb thermal expansion. Since the accumulator piston 69 is provided near the axis inside the joint, the space space of the joint 64 can be effectively used, and
The length of the joint 64 in the axial direction can be reduced, which is advantageous from the viewpoint of vibration.

In this embodiment, the same effects as in the above embodiment can be obtained. Next, FIGS. 6 and 7 show a third embodiment of the present invention. 6 and 7, reference numeral 81 denotes a ring-shaped plug as a closing means,
The plug 81 includes an iron ring 82 and a sealing rubber film 83 covering the outer periphery.

An air chamber 85 is defined by the plug 81 and the accumulator piston 84. The air chamber 85 has a function of an air spring that absorbs expansion caused by a rise in oil temperature and pushes back the compressed oil. ing. An accumulator chamber 68 is provided between a hollow portion 67 of the rotor shaft 51 and a nut 65 screwed into a screw portion 66 of the input shaft 52.
Is formed, and an accumulator piston 84 is slidably housed in the accumulator chamber 68.

O-rings 86 and 87 are inserted into the accumulator piston 84. The plug 81 is prevented from coming off by a retainer plate 72, and the retainer plate 72 is positioned by a snap ring 74. In this embodiment, it is needless to say that the same effect as in the above embodiment can be obtained. The other configuration is the same as that of the second embodiment.

[0038]

[Effects of the Invention] As described above, according to the present invention,
If, it is possible to not receive the influence of the centrifugal force at high rotational use of joint hand, to prevent the leakage of oil from the oil seal, it is possible to improve the durability of the oil seal.

Further, no unnecessary strength is required for each part,
The size and weight can be reduced. In addition, since there is no change in the internal volume, no bubbles are generated. further,
Since there is no place where the internal volume increases, there is no suction of air or water. As a result, the joint can exhibit predetermined characteristics.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention;

FIG. 2 is a sectional view of FIG.

FIG. 3 is a diagram showing a second embodiment of the present invention;

FIG. 4 is a sectional view of FIG. 3;

FIG. 5 shows a one-way valve.

FIG. 6 is a diagram showing a third embodiment of the present invention.

FIG. 7 is a sectional view of FIG. 6;

FIG. 8 shows a conventional example.

[Explanation of symbols]

 1: Case 2: Bearing 3: Input shaft 4: Spline section 5: Screw section 6: Rotor shaft (first rotating member) 7: Joint 8: Hollow section 9: Step section 10: Small diameter section 11: Spline section 12: Hollow Part 13: Nut 14: Outer diameter part 15: Oil seal 16: Thrust block 17: Cam surface 18: Housing 19: Flat part 20: Inlay part 21: Bolt hole 22: Plunger chamber 23: Plunger 24: Return spring 25 : Suction hole 26: one-way valve 27: retainer 28: spring 29: orifice 30: opening 31: cover 32: outer peripheral groove 33: oil seal 34: O-ring 35: bearing 36: oil seal 37: accumulator chamber 38: foam Rubber 39, 40: O-ring 41: Oil hole 42: Snap ring 51: B Tap shaft (first rotating member) 52: input shaft 53: plunger chamber 54: plunger 55: return spring 56: one-way valve 57: suction hole 58: orifice 59: notch portion 60: high pressure chamber 61: oil hole 62: Inertial valve 63: Leaf spring 64: Joint 65: Nut 66: Screw part 67: Hollow part 68: Accumulator chamber 69: Accumulator piston 70: Communication hole 71: Oil passage 72: Retainer plate 73: Preload spring 74: Snap ring 75: Hole 76: Oil seal 77, 78: O-ring 79: Housing 81: Plug (closing member) 82: Iron ring 83: Rubber film for sealing 84: Accumulator piston 85: Air chamber 86, 87: O-ring

Claims (3)

(57) [Scope of request for utility model registration] A hydraulic system is provided between input and output shafts that are rotatable relative to each other, and controls the transmission torque between the input and output shafts by flowing fluid in an amount corresponding to the rotational speed difference between the two shafts. In a power transmission joint, a foam rubber that absorbs thermal expansion of oil is provided between a hollow portion of a first rotating member connected to one of the input / output shafts and an outer peripheral portion of a nut screwed into one of the input / output shafts. A hydraulic power transmission coupling, wherein an accumulator chamber for storing is formed. 2. A hydraulic system provided between input and output shafts which are relatively rotatable to flow an amount of fluid in accordance with a rotational speed difference between the two shafts and controlling a transmission torque between the input and output shafts by a flow resistance of the fluid. In the power transmission joint, an annular accumulator chamber is formed between a hollow portion of the first rotating member connected to one of the input / output shafts and a nut screwed into one of the input / output shafts, and the accumulator chamber is provided in the accumulator chamber. A hydraulic power transmission coupling characterized by housing a piston and a preload spring for pressing the accumulator piston. 3. A hydraulic system which is provided between input and output shafts which are relatively rotatable and which allows an amount of fluid to flow in accordance with a rotational speed difference between the two shafts and controls a transmission torque between the input and output shafts by a flow resistance of the fluid. In the power transmission joint, an annular accumulator chamber is formed between a hollow portion of the first rotating member connected to one of the input / output shafts and a nut screwed into one of the input / output shafts, and the accumulator chamber is provided in the accumulator chamber. A hydraulic power transmission coupling characterized in that a piston is housed, an air chamber is formed outside the accumulator piston, and a closing member for sealing the air chamber is provided.