JP3802995B2 - Hydraulic power transmission coupling - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hydraulic power transmission joint that is used for distribution of driving force of a vehicle, and that locks when a predetermined temperature is exceeded.
[0002]
[Prior art]
Examples of conventional hydraulic power transmission joints include the following.
[0003]
The hydraulic power transmission joint is provided between a relatively rotatable input / output shaft, connected to the one shaft, and a cam housing formed on a cam surface having two or more ridges on an inner surface;
A rotor coupled to the other shaft and rotatably accommodated in the cam housing, and having a plurality of plunger chambers formed in the axial direction;
A plurality of plungers which are received in the plurality of plunger chambers so as to be able to reciprocate under the pressure of a return spring, and which are driven by the cam surface when the two shafts rotate relative to each other;
A suction / discharge hole formed in the rotor and communicating with the plunger chamber;
A plurality of suction ports that are slidably contacted with the end surface of the rotor and are positioned in a predetermined relationship with the cam housing and act as a suction valve and a discharge valve depending on the positional relationship with the suction and discharge holes, and a discharge port A rotary valve with a port formed on the surface;
Flow resistance generating means for generating a flow resistance by the flow of discharged oil by driving the plunger;
Torque is transmitted according to the rotational speed difference between the two shafts.
[0004]
In such a hydraulic power transmission joint, when the vehicle continuously travels in a place where high torque is generated, such as sandy ground, the hydraulic power transmission joint cannot be cooled and overheats, resulting in damage.
[0005]
To solve such problems, a temperature-sensitive relief mechanism that prevents the generation of torque by operating the temperature switch and forcibly opening the relief valve when the oil temperature exceeds a certain level in order to protect the joint. Has also been proposed.
[0006]
In addition, a mechanism has been proposed that uses a shape memory alloy or the like to close the high-pressure circuit so as not to generate differential rotation and reduce the heat generation energy when the oil temperature exceeds a certain level.
[0007]
The relief valve is used, for example, as shown in FIG. In FIG. 10, reference numeral 201 denotes an oil bath that stores lubricating oil (oil). The oil in the oil bath 201 is sucked up by the pump 202 and operates the piston 204 via the check valve 203. The piston 204 presses the plate 205 and fastens the clutch 206. When the oil temperature in the oil passage 207 exceeds a certain value, the relief valve 208 is opened and the oil is returned to the oil strainer 201.
[0008]
As shown in FIG. 11, the relief valve 208 includes a ball 210 that closes the relief hole 209 of the oil passage 207 and a spring 211 that biases the ball 210. A temperature switch 212 is inserted into the oil passage 207. When the temperature switch 212 reaches a certain oil temperature or higher, the ball 210 is pushed to open the drain hole 209.
[0009]
As shown in FIG. 12, the ball 210 is seated on a tapered valve seat 213 formed in the opening of the drain hole 209 and is urged so as to be pressed against the valve seat 213 by a spring 211. In this state, the drain hole 209 is closed. When the oil temperature reaches a certain value or more, the temperature switch 212 in FIG. 11 is activated, and the ball 210 is pushed by the temperature switch 212 to open the drain hole 209. Oil from the oil passage 207 is drained through the drain hole 209, and hydraulic relief is performed.
[0010]
In addition, as shown in FIGS. 13 and 14, there are some which are locked using a spring of a shape memory alloy.
[0011]
13 and 14, a storage hole 222 is formed in the rotary valve 221, and the lock pin member 223 is movably stored in the storage hole 222. A spring 225 made of a shape memory alloy is interposed between the large diameter portion 224 formed on the outer periphery of the lock pin member 223 and the inner wall of the accommodation hole 222, and the plug 226 that closes the large diameter portion 224 and the accommodation hole 222. Ordinary springs 227 and 228 are interposed therebetween. When the temperature is lower than the predetermined value, the spring 225 is not deformed, the lock pin member 223 is urged by the springs 227 and 228 as indicated by the arrow a, and the tip of the lock pin member 223 protrudes from the hole 229. Yes. In this state, normal torque characteristics can be obtained.
[0012]
When the temperature exceeds a predetermined value, the spring 225 made of a shape memory alloy is deformed, and the lock pin member 223 moves in the direction indicated by the arrow b. Thus, the orifice is closed and locked, and the rigid 4WD state is changed. obtain.
[0013]
[Problems to be solved by the invention]
However, in such a conventional hydraulic power transmission joint, when the relief valve shown in FIG. 10 to FIG. 12 is used, the oil temperature rises during traveling that requires torque such as sand or deep snow. When the value exceeds the predetermined value, there is a problem that the torque is lowered and the running performance is lowered.
[0014]
Moreover, as shown in FIG. 13 and FIG. 14, when the shape memory alloy is used, the problem of runnability is solved, but once the rigid 4WD is reached, a certain period of time has passed and the oil temperature has not decreased. Since the orifice is not opened and the differential rotation of the front and rear wheels cannot be absorbed, there is a problem that a tight corner braking phenomenon occurs when driving on a high μ road corner in a locked state.
[0015]
The present invention has been made to solve such a conventional problem, and does not impair running performance, and does not lock unless a certain torque or more is generated, so that a tight corner braking phenomenon does not occur. An object is to provide a power transmission coupling.
[0016]
[Means for Solving the Problems]
According to a first aspect of the present invention, the cam housing is provided between the input / output shafts capable of relative rotation, is connected to the one shaft, and is formed on a cam surface having two or more ridges on the inner surface;
A rotor coupled to the other shaft and rotatably accommodated in the cam housing, and having a plurality of plunger chambers formed in the axial direction;
A plurality of plungers which are received in the plurality of plunger chambers so as to be able to reciprocate under the pressure of a return spring, and which are driven by the cam surface when the two shafts rotate relative to each other;
A suction / discharge hole formed in the rotor and communicating with the plunger chamber;
A plurality of suction ports that are slidably contacted with the end surface of the rotor and are positioned in a predetermined relationship with the cam housing and act as a suction valve and a discharge valve depending on the positional relationship with the suction and discharge holes, and a discharge port A rotary valve with a port formed on the surface;
Flow resistance generating means for generating a flow resistance by the flow of discharged oil by driving the plunger;
In the hydraulic power transmission joint that transmits torque according to the rotational speed difference between the two shafts,
A lock pin member for closing the orifice as the flow resistance generating means by freeing the valve body that has been moved and held when the hydraulic pressure rises above a predetermined value;
A plug member that forms a hydraulic chamber with the lock pin member and holds a spring that biases the lock pin member;
A ball that opens and closes the drain hole formed in the plug member and a temperature switch that opens the drain hole by pressing the ball when the temperature reaches a predetermined value or more are provided.
[0017]
The invention of claim 2 is a lock pin member for closing the orifice as the flow resistance generating means by freeing the valve body that has been moved and held when the hydraulic pressure rises above a predetermined value;
A plug member that forms a damper chamber with an orifice opening between the lock pin member and a spring that biases the lock pin member via the piston member;
A ball that opens and closes a drain hole formed in the plug member;
A temperature switch is provided that opens the drain hole by pushing the ball when the temperature exceeds a predetermined value.
[0018]
According to a third aspect of the present invention, there is provided a lock pin member for closing the orifice as the flow resistance generating means by freeing the valve body that has been moved and held when the hydraulic pressure rises to a predetermined value or more;
A plug member that forms a damper chamber with the lock pin member and holds a spring that biases the lock pin member;
An orifice that passes through the damper chamber and the low pressure side of the plug member to delay the movement of the lock pin member;
A ball for opening and closing the orifice;
When the temperature is lower than a predetermined value, the ball is pressed to close the orifice, and when the temperature is equal to or higher than the predetermined value, an opening / closing member made of a bimetal is provided to deform and move the ball to open the orifice.
[0019]
According to the present invention having such a configuration, when the temperature exceeds a predetermined value, the ball that opens and closes the drain hole formed in the plug member is pushed by the temperature switch so that the drain hole is opened. When the value exceeds a predetermined value, the torque does not decrease, the running performance is not deteriorated, and if a certain torque or more does not occur, the lock does not occur and the tight corner braking phenomenon does not occur.
[0020]
In addition, the oil temperature is locked in a high energy generation state where the oil temperature does not rise above a certain temperature, and the differential rotation speed becomes almost zero, so that heat generation can be suppressed.
[0021]
In addition, when the temperature exceeds a predetermined value, the mechanism that opens the drain hole by pressing a ball that opens and closes the drain hole formed in the plug member with a temperature switch, and the piston member housed in the lock pin member and the plug member A damper chamber is formed between the damper chamber and a lock damper mechanism that opens an orifice in the damper chamber, so that not only the above-mentioned effects can be obtained, but also a lock shock is not felt, and the temperature is a predetermined value. In these cases, the locked state can be achieved without delay.
[0022]
Furthermore, when the temperature is higher than a predetermined value, the opening and closing member made of bimetal frees the ball and opens the orifice so that the lock pin member can move, so that the above effects can be obtained, and further a lock shock is felt. There is nothing.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a sectional view showing an embodiment of the present invention.
[0024]
In FIG. 1, reference numeral 1 denotes a cam having a cam surface 2 having two or more ridges on the inner surface. The cam 1 is connected to an output shaft (not shown) and rotates integrally with the output shaft. Further, the cam 1 is fixed to the cam housing 4 by the welded portion 3, and the cam 1 rotates integrally with the cam housing 4.
[0025]
A rotor 5 is rotatably housed in the cam housing 4. The rotor 5 is coupled to the input shaft 6 and rotates integrally with the input shaft 6.
[0026]
A plurality of plunger chambers 7 are formed in the rotor 5 in the axial direction, and a plurality of plungers 8 are slidably accommodated in the plunger chamber 7 via return springs 9. A plurality of suction / discharge holes 10 are formed in the rotor 5 so as to communicate with the plunger chambers 7.
[0027]
Reference numeral 11 denotes a rotary valve having a suction port 12, a suction path 13 and a discharge port 14 formed on the surface, and a communication groove 15 communicating with each of the discharge ports 14 is formed on the back surface of the rotary valve 11. Further, a lid member 16 is provided in close contact with the back surface, and the communication groove 15 is closed.
[0028]
The rotary valve 11 also has a positioning projection 18 that engages with a notch 17 formed on the inner periphery of the cam housing 4.
[0029]
The rotary valve 11 constitutes a timing member that determines the opening / closing timing of the suction / discharge hole 10, and the notch 17 and the protrusion 18 constitute a positioning mechanism that regulates the phase relationship between the cam 1 and the rotary valve 11.
[0030]
When the plunger 8 is in the suction process, a positional relationship is established between the suction port 12 of the rotary valve 11 and the suction / discharge hole 10 of the rotor 5, and an orifice, a suction port 12, a suction path 13, and a suction / discharge hole of the rotor 5 described later. Through 10, oil can be sucked into the plunger chamber 7.
[0031]
Further, when the plunger 8 is in the discharge process, the relationship is reverse to that of the suction process, and the suction / discharge hole 10 of the rotor 5 communicates with the communication groove 15 via the discharge port 14 of the rotary valve 11.
[0032]
A bearing retainer 19 that rotates integrally with the cam housing 4 supports the input shaft 6 via a bearing 20. A thrust needle bearing 21 is interposed between the bearing retainer 19 and the rotary valve 11, and the friction torque on the thrust needle bearing 21 side is set to be smaller than the friction torque between the rotor 5 and the rotary valve 11. Yes.
[0033]
Accordingly, when the direction of the differential rotation is changed, the rotary valve 11 rotates together with the rotor 5 and rotates until the positioning projection 18 of the rotary valve 11 hits the notch 17 of the cam housing 4. Rotate with. Thereby, the suction / discharge hole 10 is forcibly switched at a predetermined timing even during forward rotation or reverse rotation.
[0034]
An oil seal 22 is provided between the bearing retainer 19 and the input shaft 6, and an accumulator piston 23 for absorbing thermal expansion / contraction of oil is slidably accommodated inside the input shaft 6. . A cover member 24 prevents muddy water from entering the O-ring sliding portion of the accumulator chamber 25.
[0035]
The accumulator chamber 25 communicates with the inside of the joint via oil passages 26 and 27. The rotary valve 11 is formed with a high pressure chamber 28 that communicates with the discharge port 14, and the outlet of the high pressure chamber 28 is closed by a plug 29. In addition, 30 is an oil supply hole, 31 is a needle bearing, 32 is a screw hole, 33 and 34 are O-rings, 35 and 36 are snap rings, and 37 is a mounting hole.
[0036]
FIG. 2 is a sectional view of the rotary valve 11.
[0037]
In FIG. 2, 11 is a rotary valve, and the rotary valve 11 is formed with a storage chamber 39 in which a ball (valve element) 38 is movably stored. The storage chamber 39 communicates with the discharge port 14 via the high-pressure passage 40. A storage hole 41 is formed in the rotary valve 11, and a storage member 43 for inserting the lock pin member 42 is inserted into the storage hole 41. A communication hole 45 is formed in the bottom wall of the storage member 43 to allow communication between the chamber 44 formed inside the storage member 43 and the storage chamber 39. A valve seat 46 is formed at the inlet of the communication hole 45, and the ball 38 is seated on the valve seat 46 in the locked state to close the communication hole 45.
[0038]
The lock pin member 42 has a small-diameter pin portion 47 and a large-diameter large-diameter portion 48, and the position of the ball 38 is controlled by the lock pin member 42. A gap between the pin portion 47 and the communication hole 45 is an orifice 49 as a flow resistance generating means. Therefore, the hole diameter of the communication hole 45 can be increased and the hole diameter accuracy can be made rough.
[0039]
When the ball 38 is held by the lock pin member 42, the orifice 49 is open, but when the ball 38 becomes free, the ball 38 is seated on the valve seat 46 of the storage member 43 and closes the orifice 49. To do.
[0040]
A recess 50 is formed on the outer periphery of the large-diameter portion 48 of the lock pin member 42, and a seal member 51 is interposed in the recess 50. A plug 52 is screwed into the storage member 43 stored in the storage hole 41, and a spring holding member 55 having an opening 54 is provided inside the plug 52. Two springs 56 and 57 are interposed between the spring holding member 55 and the lock pin member 42. The lock pin member 42 is normally biased leftward in the figure by springs 56 and 57 to hold the ball 38. A drain hole 58 is formed in the plug 52, and the drain hole 58 is normally closed by a ball 59 pressed by a spring holding member 55 that holds springs 56 and 57.
[0041]
A groove 60 communicating with the drain hole 58 is formed in the plug 52, and a discharge hole 61 is formed in the plug 52 and the rotary valve 11, respectively.
[0042]
A concave portion 62 is formed in the plug 52, a temperature switch 63 is inserted into the concave portion 62, and a pin portion 64 of the temperature switch 63 is inserted into the drain hole 58 so as to contact the ball 59. An L-shaped sheet metal member 65 is fixed to the rotary valve 11 with a bolt 66, and a temperature switch 69 is held by the sheet metal member 65.
[0043]
When the temperature of the temperature switch 63 exceeds a predetermined value, the pin portion 64 protrudes to push the ball 59, the ball 59 pushes the spring holding member 55 against the springs 56, 57, and the drain hole 58 is opened. A hydraulic chamber 67 is formed between the plug 52 and the lock pin member 42, and the hydraulic chamber 67 is filled with oil.
[0044]
Next, the operation will be described.
[0045]
In FIG. 1, when there is no rotational difference between the cam 1 and the rotor 5, the plunger 8 does not operate and torque is not transmitted. At this time, the plunger 8 is pressed against the cam surface 2 by the return spring 9.
[0046]
Next, when a rotational difference is generated between the cam 1 and the rotor 5, the plunger 8 in the discharge stroke is pushed in the axial direction by the cam surface 2 of the cam 1.
[0047]
At this time, since the suction / discharge hole 10 communicates with the discharge port 14, the plunger 8 pushes the oil in the plunger chamber 7 from the suction / discharge hole 10 to the discharge port 14 of the rotary valve 11.
[0048]
The oil pushed out to the discharge port 14 is supplied from the suction passage 13 to the suction port 12 through the orifice. At this time, the hydraulic pressure of the discharge port 14 and the plunger chamber 7 increases due to the resistance of the orifice, and a reaction force is generated in the plunger 8.
[0049]
Torque is generated by rotating the cam 1 against the plunger reaction force, and torque is transmitted between the cam 1 and the rotor 5. In addition, since the discharge port 14 is connected by the communication groove 15, the hydraulic pressure of all the plunger chambers 7 in the discharge stroke becomes equal.
[0050]
Further, when the cam 1 rotates, the suction stroke is started and the suction / discharge hole 10 communicates with the suction port 12, so that the oil in the suction path 13 is sucked into the plunger chamber 7 through the suction port 12 and the suction / discharge hole 10, The plunger 8 returns along the cam surface 2 of the cam 1.
[0051]
In FIG. 2, the ball 59 is pressed against the drain hole 58 by the spring holding member 55 that holds the springs 56 and 57 during normal running, and the drain hole 58 is closed, so that the oil in the hydraulic chamber 67 cannot escape. The lock pin member 42 does not move. Therefore, since the lock pin member 42 holds the ball 38 as a valve body and the ball 38 opens the communication hole 45, the discharge pressure from the discharge port 14 is discharged from the high pressure passage 40 and the storage chamber 39 to the orifice. 49 and discharged to the low pressure side.
[0052]
Therefore, a normal torque characteristic is shown as indicated by A in FIG. In FIG. 3, B indicates a high torque × high differential region, and a normal torque characteristic passing through the high torque × high differential region B is obtained.
[0053]
Next, when the engine is operated for a long time in the high torque × high differential range B in FIG. 3, the heat generation energy is high, so that the oil temperature in the joint rises and when the temperature exceeds a predetermined value, the temperature switch 63 is activated, The pin portion 64 presses the ball 59.
[0054]
The ball 59 presses the spring holding member 55 against the springs 56 and 57, leaves the drain hole 58 and opens the drain hole 58. Oil in the hydraulic chamber 67 drains to the low pressure side through the drain hole 58, the groove 62, and the discharge hole 61. For this reason, the lock pin member 42 can move, and when the hydraulic pressure acting on the pin portion 47 of the lock pin member 42 exceeds a predetermined value, the lock pin member 42 moves to the right in the figure and the ball 38 becomes free. Thus, the communication hole 45 is closed and the orifice 49 is closed. As described above, when the torque exceeds a certain level, the spring force of the springs 56 and 57 is overcome, and the lock pin member 42 moves to enter a locked state.
[0055]
The torque characteristic at this time is a lock characteristic as indicated by C in FIG. When the value is smaller than high torque × high differential range B, the lock state is established.
[0056]
In this way, when the temperature exceeds a predetermined value, 2WD is not achieved, so that the running performance is not impaired, and when a certain torque or more does not occur, the lock does not lock, and the tight corner braking phenomenon. Does not occur. Also, in a high energy generation state {ΔN × ΔT ≧ C (constant value)} in which the oil temperature of the joint rises above a certain temperature, the joint is locked and the differential rotational speed ΔN≈0, so heat generation is suppressed.
[0057]
5 to 7 are cross-sectional views showing the main part of a second embodiment of the present invention.
[0058]
In FIG. 5, the discharge port 14 and the suction port 12 are alternately formed in the circumferential direction in the rotary valve 11, and the suction port 12 communicates with the suction path 13. A protrusion 18 formed on the outer periphery of the rotary valve 11 engages with a notch 17 formed on the inner periphery of the cam housing 4. A storage hole 71 is formed in the rotary valve 11, and a storage member 74 in which a storage chamber 73 for storing a ball 72 serving as a valve body is inserted is inserted into the storage hole 71. The housing hole 71 is closed by screwing.
A ball 72 is movably stored in the storage chamber 73, and the storage chamber 73 communicates with the discharge port 14 through a high-pressure path (not shown).
[0059]
The rotary valve 11 is formed with another storage hole 77 in which the lock pin member 76 is movably stored. The storage hole 77 is connected to a communication hole 78 formed in the rotary valve 11 and a communication hole 79 formed in the storage member 74. And communicates with the storage chamber 73. A low pressure hole 80 is formed in the storage hole 77. Oil is discharged from the low pressure hole 80 to the low pressure side. The lock pin member 76 is movably inserted into the communication holes 78 and 79, and a small diameter pin portion 81 that presses and holds the ball 72 in a normal state, and a large diameter in which a seal member 83 is inserted into a groove 82 formed on the outer periphery. The large-diameter portion 84 and a stopper portion 85 that regulates the amount of movement of the lock pin member 76 to be constant.
[0060]
A gap between the pin portion 81 of the lock pin member 76 and the communication hole 78 formed in the rotary valve 11 forms an orifice 86 as a flow resistance generating means. When the lock pin member 76 moves in the left direction in the drawing and the ball 72 becomes free, the ball 72 closes the communication hole 79 and the orifice 86 is closed to be locked.
[0061]
The rotary valve 11 has a storage hole 87 communicating with the storage hole 77, and a plug 89 having a hydraulic chamber 88 formed therein is screwed into the storage hole 87. A piston member 91 urged rightward in the drawing by a spring 90 is movably accommodated in the hydraulic chamber 88, and a seal member 93 is interposed in a groove 92 formed on the outer periphery of the piston member 91. Between the piston member 91 and the lock pin member 76, a spring 94 for biasing the lock pin member 76 in the right direction in the figure is interposed, and a damper chamber 95 in which the spring 94 is accommodated is formed. An orifice 96 is opened in the damper chamber 95. The orifice 96 communicates with the low pressure side and delays the movement of the lock pin member 76, thereby preventing a shock felt by the lock. The hydraulic chamber 88 is sealed by a seal member 93 provided on the piston member 91 so that the oil in the hydraulic chamber 88 does not flow into the damper chamber 95 and flow out of the orifice 96.
[0062]
The rotary valve 11 is further formed with another storage hole 97 communicating with the damper chamber 95, and a plug 98 is screwed into the storage hole 97. The plug 98 is formed with a suction hole 99 that communicates the damper chamber 95 with the low pressure side outside the rotary valve 11, and the suction hole 99 is opened and closed by a ball 100. When locking, the ball 100 closes the suction hole 99, and when unlocked, the ball 100 opens the suction hole 99 and sucks oil into the damper chamber 95.
[0063]
A drain hole 101 communicating with the hydraulic chamber 88 formed in the plug 89 and the low pressure side outside the rotary valve 11 is formed in the plug 89, and the drain hole 101 is opened and closed by a ball 102. A temperature switch 104 is accommodated in a recess 103 formed in the plug 89, and a pin portion 105 of the temperature switch 104 is movably inserted into the drain hole 101.
[0064]
When the temperature reaches a predetermined value or more, the temperature switch 104 is activated, and the pin portion 105 pushes the ball 102 to open the drain hole 101. When the drain hole 101 is opened, the piston member 91 becomes movable, is pressed by the stopper portion 85 of the lock pin member 76, and moves leftward in the figure. A lid member 106 is provided outside the temperature switch 104, and the temperature switch 104 is prevented from being detached from the plug 89 by the lid member 106. The lid member 106 is provided with a discharge hole 107 communicating with the drain hole 101.
[0065]
Next, the operation will be described.
[0066]
During normal running, the lock pin member 76 does not move and holds the ball 72 as shown in FIG. The orifice 86 formed by the gap between the communication hole 78 and the pin portion 81 of the lock pin member 76 is open, and the discharge pressure (internal pressure) from the discharge port 14 passes through the storage chamber 73, the communication hole 79, and the orifice 86. It is discharged from the low pressure hole 80 to the low pressure side.
[0067]
When the temperature is lower than the predetermined value, the temperature switch 104 does not operate and the drain hole 101 is closed by the ball 102. The piston member 91 cannot move leftward. The torque characteristics at this time are normal torque characteristics as shown in FIG.
[0068]
Next, as shown in FIG. 6, when the front and rear wheel differential rotation speed ΔN exceeds a predetermined value, the hydraulic pressure in the storage chamber 73 rises, and the force pushing the lock pin member 76 by the hydraulic pressure in the storage chamber 73 is exerted by the spring 94. Since the force is greater than the force that pushes the lock pin member 76, the lock pin member 76 tries to move to the left. However, the damper chamber 95 behind the lock pin member 76 is filled with oil, and the oil fills the orifice 96. Therefore, the movement of the lock pin member 76 is delayed.
[0069]
Therefore, even if the peak torque is generated when the low μ road starts, the lock pin member 76 does not move to the left at that moment, so it is not locked. As a result, you will not feel a rock shock.
[0070]
As shown in FIG. 7, when the temperature reaches a predetermined value or more, the temperature switch 104 is activated, and the pin portion 105 of the temperature switch 104 pushes the ball 102 to open the drain hole 101. The lock pin member 76 further moves to the left, pushes the piston member 91 with the stopper portion 85, and rapidly moves to the left. For this reason, the ball 72 is in a locked state in order to close the communication hole 79 and close the orifice 86. The torque characteristic at this time is a lock characteristic as shown in FIG.
[0071]
When the hydraulic pressure in the storage chamber 73 decreases and the force pushing the lock pin member 76 by the spring 94 becomes larger than the force pushing the lock pin member 76 by the hydraulic pressure in the storage chamber 73, the lock pin member 76 moves rightward in the figure. The ball 72 is held and the oil passes through the orifice 86. Further, when the temperature becomes lower than the predetermined value, the temperature switch 104 does not operate, returns to the original state, and the ball 102 closes the drain hole 101. In such unlocking, the ball 100 opens the suction hole 99 and the oil is sucked into the damper chamber 95, so that the unlocking can be performed instantaneously.
[0072]
In this embodiment, the same effects as those of the above embodiment can be obtained, and further, the lock shock can not be felt, and the locked state can be achieved without delay at the time of locking.
[0073]
8 and 9 are cross-sectional views showing the main part of the third embodiment of the present invention.
[0074]
In FIG. 8, the rotary valve 11 is formed with a high pressure chamber 111 communicating with the discharge port 14, and a cured color member 112 is accommodated in the high pressure chamber 111.
[0075]
A storage chamber 114 in which a ball 113 as a valve body is movably stored is formed in the collar member 112. The storage chamber 114 communicates with the communication hole 116 through the opening 115.
[0076]
The communication hole 116 communicates with a storage hole 118 that stores the lock pin member 117, and the lock pin member 117 is slidably stored in the storage hole 118. The lock pin member 117 has a small-diameter pin portion 119, a large-diameter large-diameter portion 120, and a stopper portion 121, and the position of the ball 113 is controlled by the lock pin member 117. A groove 122 is formed in the large diameter portion 120 of the lock pin member 117, and an oil seal 123 is interposed in the groove 122.
[0077]
A gap between the pin portion 119 and the communication hole 116 serves as an orifice 124 as a flow resistance generating means. Therefore, the hole diameter of the communication hole 116 can be formed large, and the hole diameter accuracy can be roughened.
[0078]
The storage hole 118 on the pin portion 119 side is formed with a low pressure hole 125 communicating with the low pressure side. The oil that has passed through the orifice 124 is discharged from the low pressure hole 125 to the low pressure side.
[0079]
When the ball 113 is held by the lock pin member 117, the orifice 124 is open. However, when the ball 113 becomes free, the ball 113 is seated on a valve seat 126 formed on the collar member 112, and the orifice 124. Close.
[0080]
A plug 127 is screwed into the storage hole 118 and is closed by the plug 127. A step 128 is formed inside the plug 127, and a spring receiving portion 129 is provided on the step 128. A spring 130 is interposed between the spring receiving portion 129 and the lock pin member 117.
[0081]
The lock pin member 117 housed in the housing hole 118 is biased by the spring 130 to hold the ball 113, and when the oil pressure in the housing chamber 114 for housing the ball 113 rises above a predetermined value, the lock pin member 117 117 moves to the right against the spring 130, and the stopper 121 comes into contact with the spring receiver 129. The stopper portion 121 of the lock pin member 117 prevents the lock pin member 117 from moving beyond a certain distance.
[0082]
A communication hole 131 is formed in the spring receiving portion 129, and the chamber 132 behind the lock pin member 117 and the chamber 134 for storing the ball 133 communicate with each other through the communication hole 131. The chamber 132 and the chamber 134 form a damper chamber for delaying the movement of the lock pin member 117 in the right direction.
[0083]
A locking member 136 to which an opening / closing member 135 made of bimetal is attached is locked to the end of the plug 127. Suction holes 137 and 138 are formed in the plug 127 and the locking member 136, and the suction holes 137 and 138 are opened and closed by balls 133. When locking, the ball 133 closes the suction holes 137 and 138, and when unlocked, the ball 133 opens the suction holes 137 and 138 and the chamber 132 and the chamber 134 suck oil.
[0084]
The plug 127 is formed with an orifice 139 for delaying the movement of the lock pin member 117, and an accommodating portion 141 for accommodating the ball 140 is formed on the outlet side of the orifice 139. The opening / closing member 135 made of bimetal does not deform when the temperature is lower than a predetermined value, and presses the ball 140 to close the orifice 139. When the temperature exceeds the predetermined value, the opening / closing member 135 is deformed and separated from the ball 140, open.
[0085]
Next, the operation will be described.
[0086]
Since the temperature is lower than a predetermined value during normal travel, the opening / closing member 135 made of bimetal does not deform, presses the ball 140, and closes the orifice 139. The ball 133 closes the suction holes 137 and 138. Since the oil in the chamber 132 and the chamber 134 cannot escape, the lock pin member 117 does not move. For this reason, the lock pin member 117 holds the ball 113, and the oil from the discharge port 14 passes through the storage chamber 114, the opening 115, and the orifice 124 and is discharged from the low pressure hole 125 to the low pressure side. For this reason, the torque characteristic shows a normal torque characteristic as shown in A of FIG.
[0087]
When operating for a long time in the high torque x high differential range shown by B in FIG. 3, since the heat generation energy is high, when the oil temperature rises and exceeds a predetermined value, the opening / closing member 135 made of bimetal deforms, Open from the orifice 139 and open the orifice 139. Therefore, the oil in the chamber 132 and the chamber 134 can be drained from the orifice 139, and the lock pin member 117 can move.
[0088]
In this case, since the oil filled in the chamber 132 and the chamber 134 passes through the orifice 139, the movement of the lock pin member 117 is delayed.
[0089]
For this reason, even if a peak torque is generated when starting on a low μ road, the lock pin member 117 does not move rightward at that moment, so it does not lock. As a result, you will not feel a rock shock.
[0090]
On the other hand, when high driving force is required (when high torque is sustained), the oil filling the chamber 132 and the chamber 134 behind the lock pin member 117 passes through the orifice 139 and is discharged to the low pressure side. Since the lock pin member 117 moves to the right after a few seconds with a delay, the ball 113 held by the lock pin member 117 becomes free and the orifice 124 is closed. The torque characteristic at this time is a lock characteristic as shown in FIG. Therefore, the running performance of the vehicle is maintained in this locked state.
[0091]
When the hydraulic pressure in the storage chamber 114 decreases and the force pushing the lock pin member 117 by the spring 130 becomes larger than the force pushing the lock pin member 117 by the hydraulic pressure in the storage chamber 114, the lock pin member 117 moves to the left in the figure. , The ball 113 is held, and the oil passes through the orifice 124. In such unlocking, the ball 133 is free from the suction hole 137, the suction holes 137 and 138 are opened, the oil is sucked into the chamber 132 and the chamber 134, and the unlocking can be instantaneously performed. Thus, the lock can be released instantaneously while maintaining the damper effect.
[0092]
When the temperature falls below a predetermined value, the opening / closing member 135 made of bimetal returns to the original state and presses the ball 140 to close the orifice 139.
[0093]
【The invention's effect】
As described above, according to the present invention, when the temperature exceeds a predetermined value, the ball that opens and closes the drain hole formed in the plug member is pushed by the temperature switch to open the drain hole. In this case, the torque does not decrease, the running performance is not impaired, and if the torque exceeds a certain value, the lock is not generated and the tight corner braking phenomenon does not occur.
[0094]
In addition, the oil temperature is locked in a high energy generation state where the oil temperature does not rise above a certain temperature, and the differential rotation speed becomes almost zero, so that heat generation can be suppressed.
[0095]
In addition, when the temperature exceeds a predetermined value, the mechanism that opens the drain hole by pressing a ball that opens and closes the drain hole formed in the plug member with a temperature switch, and the piston member housed in the lock pin member and the plug member The damper chamber is formed between the two and the lock damper mechanism that opens the orifice in the damper chamber, so that not only the above effects can be obtained, but also the lock shock is not felt, and the temperature is not less than a predetermined value. In the case of, it can be locked without delay.
[0096]
Furthermore, when the temperature is higher than a predetermined value, the opening and closing member made of bimetal frees the ball and opens the orifice so that the lock pin member can move. I don't feel it.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a first embodiment of the present invention.
FIG. 2 is a cross-sectional view of the main part showing the first embodiment of the present invention.
FIG. 3 is a graph showing normal torque characteristics.
FIG. 4 is a graph showing a transition from normal torque characteristics to lock characteristics.
FIG. 5 is a sectional view (No. 1) showing a main part of a second embodiment of the present invention.
FIG. 6 is a sectional view (No. 2) showing a main part of a second embodiment of the present invention.
FIG. 7 is a sectional view (No. 3) showing main parts of a second embodiment of the present invention.
FIG. 8 is a sectional view (No. 1) showing main parts of a third embodiment of the present invention.
FIG. 9 is a sectional view (No. 2) showing main parts of a third embodiment of the present invention.
FIG. 10 is a diagram showing an example of using a conventional relief valve
FIG. 11 is a view showing a conventional relief valve and a temperature switch.
FIG. 12 is a sectional view of a conventional relief valve.
FIG. 13 is a diagram showing a lock mechanism using a conventional shape memory alloy (part 1).
FIG. 14 is a diagram showing a lock mechanism using a conventional shape memory alloy (part 2).
[Explanation of symbols]
1: Cam
2: Cam surface
3: Welded part
4: Cam housing
5: Rotor
6: Input shaft
7: Plunger chamber
8: Plunger
9: Return spring
10: Suction / discharge hole
11: Rotary valve
12: Inhalation port
13: Inhalation route
14: Discharge port
15: Communication groove
16: Lid member
17: Notch
18: Projection
19: Bearing retainer
20: Bearing
21: Thrust needle bearing
22: Oil seal
23: Accumulator piston
24: Lid member
25: Accumulator room
26, 27: Oil passage
28: High pressure chamber
29: Plug
30: Lubrication hole
31: Needle bearing
32: Screw hole
33, 34: O-ring
35, 36: Snap ring
37: Mounting hole
38: Ball (valve)
39: Storage room
40: High-pressure road
41: Storage hole
42: Lock pin member
43: Storage member
44: Room
45: Communication hole
46: Valve seat
47, 64: Pin part
48: Large diameter part
49: Orifice (flow resistance generating means)
50, 62: recess
51: Seal member
52: Plug (plug member)
54: Opening
55: Spring holding member
56, 57: Spring
58: Drain hole
59: Ball
60: Groove
61: Discharge hole
63: Temperature switch
65: Sheet metal member
66: Bolt
67: Hydraulic chamber
71, 77, 87, 97: storage hole
72, 100, 102: Ball
73: Storage room
74: Storage member
75, 89, 98: Plug
76: Lock pin member
78, 79: Communication hole
80: Low pressure hole
81, 105: Pin part
82, 92: Groove
83, 93: Seal member
84: Large diameter part
85: Stopper
86, 96: Orifice
88: Hydraulic room
90: Belleville spring
91: Piston member
94: Spring
95: Damper room
99: Suction hole
101: Drain hole
103: Recess
104: Temperature switch
106: Lid member
107: discharge hole
111: High pressure chamber
112: Color member
113: Ball (valve)
114: Storage room
115: opening
116, 131: communication hole
117: Lock pin member
118: Storage hole
119: Pin part
120: Large diameter portion
121: Stopper
122: Groove
123: Oil seal
124, 139: Orifice
125: Low pressure hole
126: Valve seat
127: Plug
128: Step
129: Spring receiving part
130: Spring
132,134: Room
133, 140: Ball
135: Opening / closing member
136: Locking member
137, 138: suction hole
139: Orifice
141: Storage section

Claims (3)

A cam housing provided between the relatively rotatable input / output shafts, connected to the one shaft, and formed on a cam surface having two or more ridges on the inner surface;
A rotor coupled to the other shaft and rotatably accommodated in the cam housing, and having a plurality of plunger chambers formed in the axial direction;
A plurality of plungers which are received in the plurality of plunger chambers so as to be able to reciprocate under the pressure of a return spring, and which are driven by the cam surface when the two shafts rotate relative to each other;
A suction / discharge hole formed in the rotor and communicating with the plunger chamber;
A plurality of suction ports that are slidably contacted with the end surface of the rotor and are positioned in a predetermined relationship with the cam housing and act as a suction valve and a discharge valve depending on the positional relationship with the suction and discharge holes, and a discharge port A rotary valve with a port formed on the surface;
Flow resistance generating means for generating flow resistance by the flow of discharged oil by driving the plunger;
In the hydraulic power transmission joint that transmits torque according to the rotational speed difference between the two shafts,
A lock pin member for closing the orifice as the flow resistance generating means by freeing the valve body that has been moved and held when the hydraulic pressure rises above a predetermined value;
A plug member that forms a hydraulic chamber with the lock pin member and holds a spring that biases the lock pin member;
A hydraulic power transmission joint comprising: a ball that opens and closes a drain hole formed in the plug member; and a temperature switch that pushes the ball and opens the drain hole when a temperature exceeds a predetermined value. A cam housing provided between the input / output shafts capable of relative rotation, connected to the one shaft, and formed on a cam surface having two or more ridges on the inner surface;
A rotor coupled to the other shaft and rotatably accommodated in the cam housing, and having a plurality of plunger chambers formed in the axial direction;
A plurality of plungers which are received in the plurality of plunger chambers so as to be able to reciprocate under the pressure of a return spring, and which are driven by the cam surface when the two shafts rotate relative to each other;
A suction / discharge hole formed in the rotor and communicating with the plunger chamber;
A plurality of suction ports that are slidably contacted with the end surface of the rotor and are positioned in a predetermined relationship with the cam housing and act as a suction valve and a discharge valve depending on the positional relationship with the suction and discharge holes, and a discharge port A rotary valve with a port formed on the surface;
Flow resistance generating means for generating a flow resistance by the flow of discharged oil by driving the plunger;
In the hydraulic power transmission joint that transmits torque according to the rotational speed difference between the two shafts,
A lock pin member for closing the orifice as the flow resistance generating means by freeing the valve body that has been moved and held when the hydraulic pressure rises above a predetermined value;
A plug member that forms a damper chamber with an orifice opening between the lock pin member and a spring that biases the lock pin member via the piston member;
A ball that opens and closes a drain hole formed in the plug member;
A hydraulic power transmission joint comprising a temperature switch that opens the drain hole by pushing the ball when a temperature exceeds a predetermined value. A cam housing provided between the input / output shafts capable of relative rotation, connected to the one shaft, and formed on a cam surface having two or more ridges on the inner surface;
A rotor coupled to the other shaft and rotatably accommodated in the cam housing, and having a plurality of plunger chambers formed in the axial direction;
A plurality of plungers which are received in the plurality of plunger chambers so as to be able to reciprocate under the pressure of a return spring, and which are driven by the cam surface when the two shafts rotate relative to each other;
A suction / discharge hole formed in the rotor and communicating with the plunger chamber;
A plurality of suction ports that are slidably contacted with the end surface of the rotor and are positioned in a predetermined relationship with the cam housing and act as a suction valve and a discharge valve depending on the positional relationship with the suction and discharge holes, and a discharge port A rotary valve with a port formed on the surface;
Flow resistance generating means for generating a flow resistance by the flow of discharged oil by driving the plunger;
In the hydraulic power transmission joint that transmits torque according to the rotational speed difference between the two shafts,
A lock pin member for closing the orifice as the flow resistance generating means by freeing the valve body that has been moved and held when the hydraulic pressure rises above a predetermined value;
A plug member that forms a damper chamber with the lock pin member and holds a spring that biases the lock pin member;
An orifice that passes through the damper chamber and the low pressure side of the plug member to delay the movement of the lock pin member;
A ball for opening and closing the orifice;
A hydraulic device comprising a bimetal opening / closing member that presses the ball to close the orifice when the temperature is lower than a predetermined value and deforms when the temperature is higher than the predetermined value to move the ball to open the orifice Power transmission coupling.

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