JP4690360B2 - Coupling - Google Patents

Description

  The present invention relates to a coupling used for a power transmission system of a vehicle.

  An electromagnetic coupling 301 as shown in FIG. 4 is described in “Gaia New Model Car Description page 0-22, edited by Toyota Motor Corporation, issued by the service department, May 29, 1998”.

  The coupling 301 is disposed in the rear wheel side power transmission system of the four-wheel drive vehicle, and includes a rotating case 303, a hub 305, a multi-plate main clutch 307 and a pilot clutch 309, an armature 311, an electromagnet 313, a cam ring 315, and a ball cam 317. , A pressing member 319, a controller, and the like.

  The rotating case 303 is connected from the transfer to the transmission side via a propeller shaft. A drive pinion shaft 321 is splined to the hub 305, and a drive pinion gear 323 integrally formed with the drive pinion shaft 321 is a ring gear on the rear differential side (a differential device that distributes the driving force of the engine to the left and right rear wheels). Are engaged.

  The main clutch 307 is disposed between the rotation case 303 and the hub 305, and the pilot clutch 309 is disposed between the rotation case 303 and the cam ring 315.

  The ball cam 317 is provided between the cam ring 315 and the pressing member 319, and the pressing member 319 is connected to the hub 305 by a spline portion 325.

  The rotary case 303 is filled with oil, and the main clutch 307 and the pilot clutch 309 are immersed in this oil to form a wet clutch.

  The controller performs excitation of the electromagnet 313, excitation current control, excitation stop, and the like.

  When the electromagnet 313 is excited, the armature 311 is attracted and the pilot clutch 309 is pressed, and when the pilot clutch 309 is fastened, the transmission torque between the rotating case 303 and the hub 305 is applied to the ball cam 317, and the generated cam thrust is generated. The main clutch 307 is pressed and fastened via the pressing member 319 by force.

  When the coupling 301 is connected, the driving force of the engine is sent to the rear wheels and the vehicle enters a four-wheel drive state, which improves rough road performance, startability, acceleration, and stability of the vehicle body.

  When the exciting current of the electromagnet 313 is controlled, the cam thrust force of the ball cam 317 is changed by the slip of the pilot clutch 309, and the connecting force of the main clutch 307 is changed to adjust the driving force sent to the rear wheels.

  As described above, the transmission torque can be adjusted by controlling the current value of the electromagnet 313, and the above-described rough road running ability, startability, acceleration, and vehicle body stability can be further improved.

  Further, when the excitation of the electromagnet 313 is stopped, the pilot clutch 309 is released and the cam thrust force of the ball cam 317 disappears, the main clutch 307 is released and the coupling 301 is disconnected, and the vehicle enters a two-wheel drive state. .

  However, in the coupling 301, since the multi-plate pilot clutch 309 is wet, even if the excitation of the electromagnet 313 is stopped when the connection is released, drag torque (drag torque) is generated due to oil viscosity.

  When drag torque is generated in this way, transmission torque is input to the ball cam 317 due to the drag torque and a cam thrust force is generated. Therefore, the coupling force remains in the main clutch 307 (coupling 301), and the coupling is established. There was a problem that it could not be completely canceled.

  If the coupling 301 cannot be released, even if the rear wheel is disconnected and the vehicle is about to be in a two-wheel drive state, the rear wheel side cannot be completely disconnected, resulting in running resistance and engine fuel efficiency. In addition to the decrease, the intended performance may not be obtained due to the turning ability and turning ability of the vehicle.

  Further, when the coupling 301 is arranged between the engine and the speed change mechanism to be a start clutch, the start clutch is not completely released even when the connection is released. The creep phenomenon that crawls forward occurs.

  If the torque is not completely cut off by the starting clutch, it is difficult for the speed change mechanism to perform a smooth speed change, and the capacity of the synchro mechanism must be increased accordingly.

  Therefore, conventionally, in order to release the connection of the main clutch due to such drag torque, a return spring that urges the pressing member in the direction of releasing the connection of the main clutch has been known.

  However, when the return spring is used in this way, when the main clutch is to be connected, the pressing force of the main clutch needs to cancel the urging force of the return spring as shown in FIG. I had to.

  FIG. 3 shows a change in the transmission torque (T) that occurs when the excitation current value (I) of the electromagnet is changed in an apparatus having a configuration such as the coupling 301. A broken line graph 201 shows the characteristics when no return spring is used. The solid line graph 203 is a characteristic when a return spring is used.

  As described above, in order to obtain a desired transmission torque (T), it is necessary to increase the cam thrust force of the ball cam 317 by the amount corresponding to the decrease in the pressing force by the return spring. For this purpose, the excitation current value (I) must be increased. I must.

  Further, since the drag torque generated by the viscosity of the oil increases as the temperature of the oil decreases, the strength of the return spring needs to be set in accordance with the maximum drag torque.

  However, if the return spring is strengthened, the capacity of the ball cam 317 and the electromagnet 313 needs to be increased in order to counter it, so that the coupling 301 is increased in size and weight as a whole, reducing the on-vehicle performance and reducing the cost. As the electromagnet 313 increases in size, the burden on the battery increases and the fuel consumption of the engine decreases.

  In addition, if the ball cam 317 is made large, the pressing force of the main clutch 307 due to the drag torque increases, so the return spring must be further strengthened.

  Accordingly, the present invention provides a structure in which the transmission torque input through the pilot clutch is converted into a pressing force by the converting means to press the main clutch, and the pressing force of the main clutch caused by the drag torque of the pilot clutch. The purpose of this invention is to provide a coupling that can be canceled.

The coupling according to claim 1 includes an input-side and output-side torque transmission member, a main clutch that transmits torque between these torque transmission members, a pilot clutch that is intermittently operated by an operating means, The other side member connected with the pilot clutch, the one side member arranged to face the other side member, and the ball cam arranged between the one side member and the other side member are connected to the pilot clutch. And a coupling mechanism that presses and connects the main clutch via a pressing system by a conversion force generated by the transmission torque, wherein the main clutch and the pilot clutch are multi-plates. a clutch, the outer plates of the main clutch and the pilot clutch spline section respectively (55,87) With movably and torque transmission coupled axially to one side of the torque transmission member at an outer peripheral side extension portion connected to and is connected via a spline portion (57) to the inner plates of the main clutch A hub is fixed to one side member of the coupling mechanism, the main clutch is disposed radially outside the pilot clutch, an extension that moves the pressing system integrally in the pressing direction, a pilot clutch, And the other side member of the coupling mechanism, and when the main clutch is intermittently operated, a main sliding portion that slides while receiving transmission torque is provided between the extension portion and the torque transmission member on one side, It is characterized by being arranged between the extension part and the outer plate of the main clutch, and between the hub and each inner plate.

  A coupling according to a second aspect is the invention according to the first aspect, wherein the main clutch and the pilot clutch are arranged in a wrapping manner in the radial direction.

A coupling according to a third aspect is the invention according to the second aspect , wherein the coupling between the extension portion which is a pressing system even when the coupling mechanism is operated, the pilot clutch, and the other member of the coupling mechanism. The relative positional relationship of is not changed.

A coupling according to a fourth aspect is the invention according to any one of the first to third aspects, wherein the pilot clutch operating means is an electromagnet .

A coupling according to a fifth aspect is the invention according to the fourth aspect, wherein the electromagnet is attached to a rotor connected to the extension portion in a non-rotating state via a bearing .

  In the coupling of the present invention, the sliding part during intermittent operation is limited to the large-diameter main clutch side, and since the hysteresis is slight, the torque transmission characteristics can be precisely controlled, running on rough roads, starting Performance, acceleration, and stability of the vehicle body can be greatly improved.

  In addition, since the torque transmission characteristics can be accurately corrected according to changes with time of each member, a stable torque transmission characteristic can be obtained over a long period of time.

  In addition, it is not necessary to use a system for detecting the transmission torque using a torque sensor, and it is possible to avoid complication of the structure and cost increase associated therewith.

  In addition, by disposing the main clutch on the radially outer side of the pilot clutch, it is possible to obtain a large torque transmission capacity and to make it compact in the axial direction, preventing interference with peripheral members, The degree of freedom in layout increases.

  The starting clutch (coupling) 1 (one embodiment) will be described with reference to FIGS. 1 and 2. In addition, the left-right direction is the left-right direction in each figure, and the member etc. which are not giving the code | symbol are not shown in figure.

  The starting clutch 1 is used in a vehicle power transmission device 3, and FIG. 1 shows the starting clutch 1 and the power transmission device 3. An engine is arranged on the right side of the starting clutch 1, and an automatic transmission (AT) is arranged on the left side.

  The power transmission device 3 includes an input shaft 5 coupled to an engine crankshaft, a damper 7, a starting clutch 1, a coupling shaft 9 coupled to an automatic transmission side (output-side torque transmission member), and the like. .

  The starting clutch 1 includes a clutch housing 11 (input side torque transmission member: pressing member), a multi-plate main clutch 13 and a pilot clutch 15, a ball cam 17 (conversion means), an electromagnet 19 (operation means), and a pressing force of the main clutch 13. The system 21 includes fins 23 and 25 (cancellation mechanism: convex portion), a controller, and the like.

  A flange member 27 is fixed to the input shaft 5 with a bolt 29, and a ring 33 is connected to the flange member 27 via a spring 31 to constitute a damper 7.

  The ring 33 is connected to the clutch housing 11 of the starting clutch 1 by a spline portion 35 so as to be axially movable. The damper 7 absorbs engine speed fluctuations and vibrations by the damper function of the spring 31, and these speed fluctuations. And the vibration is cut off from the starting clutch 1.

  A compartment 39 is formed by a partition member 37 in the casing that houses the power transmission device 3. The compartment 39 is filled with oil, and the starting clutch 1 is accommodated in the compartment 39 and immersed in the oil. Further, a seal 41 is disposed between the partition member 37 and the clutch housing 11 to prevent mixing of the oil in the compartment 39 and the oil on the damper 7 side.

  A support member 43 is welded to the clutch housing 11, and the support member 43 is rotatably engaged with a support hole 45 formed in the input shaft 5 to support the clutch housing 11.

  The main clutch 13 includes three outer plates 47, one outer plate 49, and four inner plates 51, and is disposed between the clutch housing 11 and the clutch hub 53. The outer plates 47 and 49 are connected (locked) to a spline portion 55 formed on the inner periphery of the clutch housing 11 so as to be axially movable, and the inner plate 51 is connected to a spline portion 57 formed on the outer periphery of the clutch hub 53. It is connected (locked) so as to be movable in the axial direction.

  The outer plate 49 disposed on the right side of the outer plate 47 is positioned by a snap ring 59 attached to the clutch housing 11 and also serves as a pressing member for the main clutch 13 as described below.

  A pressure receiving portion 61 of the main clutch 13 is formed on the left end side of the clutch hub 53. The clutch hub 53 is connected to the connecting shaft 9 by a spline portion 63 and is prevented from moving rightward by a snap ring 65 attached to the connecting shaft 9. The clutch hub 53 is rotatably supported on the support member 43 by a ball bearing 67.

  The clutch housing 11 is provided with an extension 69 that surrounds the main clutch 13 and the clutch hub 53 from the axial side surface and the radial inner side.

  The pilot clutch 15 includes a plurality of outer plates 71 and an inner plate 73, and is disposed between the extension 69 of the clutch housing 11 and the cam ring 75 of the ball cam 17. The outer plate 71 is connected to a spline portion 77 formed on the inner periphery of the extension 69 so as to be movable in the axial direction, and the inner plate 73 is connected to a spline portion 79 formed on the outer periphery of the cam ring 75 so as to be movable in the axial direction. Yes.

  An armature 81 is disposed on the right side of the pilot clutch 15. The armature 81 is connected to the spline portion 77 of the extension portion 69 so as to be movable in the axial direction, and is positioned by a snap ring 83 attached to the extension portion 69.

  A rotor 85 is disposed on the left side of the pilot clutch 15. The outer periphery of the rotor 85 is connected to the spline part 87 of the extension part 69, and the rotor 85 is positioned by a snap ring 89 attached to the extension part 69 so as to move to the left together with the clutch housing 11. . The inner peripheral portion of the rotor 85 is supported on a hollow hub 93 by a needle bearing 91.

  The connecting shaft 9 passes through the hub 93 and is supported on the hub 93 via a slide bearing 95.

  A trochoid oil pump is disposed between the starting clutch 1 and the automatic transmission. The rotor 85 meshes with the inner gear so as to be relatively movable in the axial direction, and the oil pump is driven to rotate by the driving force of the engine.

  The ball cam 17 is disposed between the clutch hub 53 and the cam ring 75. Between the cam ring 75 and the rotor 85, a thrust bearing 97 that transmits the cam thrust force of the ball cam 17 to the rotor 85 and absorbs the relative rotation between the cam ring 75 and the rotor 85 is disposed.

  The electromagnet 19 is disposed in a recess provided in the rotor 85 via a predetermined air gap. The electromagnet 19 is prevented from rotating by engaging the connecting member 99 with the pump casing of the oil pump, and by the ball bearing 101. It is supported on the rotor 85. Further, the lead wire 103 is connected to an in-vehicle battery.

  Further, the rotor 85 is provided with a ring 105 made of a non-magnetic material by dividing the outer side and the inner side in the radial direction, and the inner and outer circumferences are welded to prevent a short circuit of magnetic force.

  As described above, since the clutch hub 53 is prevented from moving rightward by the snap ring 65, the cam thrust force of the ball cam 17 is applied to the clutch housing via the cam ring 75, the thrust bearing 97, the rotor 85, and the snap ring 89. 11 is moved to the left.

  The pressing system 21 of the main clutch 13 is configured by adding a snap ring 59 and an outer plate 49 to the cam ring 75, thrust bearing 97, rotor 85, snap ring 89, and clutch housing 11.

  A plurality of fins 23 and 25 are provided on the axial side wall 107 of the clutch housing 11. The fins 23 are arranged on the outermost side of the side wall portion 107 at equal intervals in the circumferential direction, and the fins 25 are arranged on the inner side in the radial direction from the fins 23 at equal intervals in the circumferential direction.

  Each of the fins 23 and 25 is formed by punching the side wall portion 107 from the right side, and has an inclined surface 109 along the oil flow direction by the rotation of the starting clutch 1 (clutch housing 11) as shown in FIG. .

  The controller performs excitation of the electromagnet 19, control of excitation current, excitation stop, and the like.

  When the electromagnet 19 is energized, the armature 81 is attracted and the pilot clutch 15 is engaged, and the engine torque is applied to the ball cam 17 between the cam ring 75 connected to the engine side by the pilot clutch 15 and the connecting shaft 9 side clutch hub 53. The pressing system 21 moves to the left by the generated cam thrust force.

  When the pressing system 21 (clutch housing 11) moves to the left, the main clutch 13 is pressed and fastened between the snap ring 59 (outer plate 49) attached to the clutch housing 11 and the pressure receiving portion 61 of the clutch hub 53.

  Thus, when the starting clutch 1 is connected, the driving force of the engine is transmitted from the starting clutch 1 to the wheels via the automatic transmission, and the vehicle can start.

  When the main clutch 13 is engaged, the relative rotation between the cam ring 75 and the rotor 85 is absorbed by the thrust bearing 97, and the sliding between the rotor 85 and the clutch housing 11 is prevented by the snap ring 89. However, the sliding portion is limited to the inside of the large-diameter main clutch 13, and the hysteresis becomes extremely weak.

  When the exciting current of the armature 81 is adjusted by controlling the exciting current of the electromagnet 19, the pilot clutch 15 slips, the cam thrust force of the ball cam 17 changes, and the transmission torque of the main clutch 13 (starting clutch 1) changes. The driving force of the engine sent to the wheels can be adjusted.

  Further, the excitation of the electromagnet 19 is stopped at the time of shifting.

  When the excitation of the electromagnet 19 is stopped, the pilot clutch 15 is released and the cam thrust force of the ball cam 17 disappears, the main clutch 13 is released, the connection of the starting clutch 1 is released, and the shifting becomes easy.

  At this time, with the rotation of the clutch housing 11 connected to the engine side, as shown in FIG. 2, oil collides with the inclined surfaces 109 of the fins 23 and 25, and the clutch housing 11 (pressing system 21) moves in the right direction. A reaction force 111 (in the direction opposite to the pressing force of the main clutch 13) is received.

  If drag torque is generated in the pilot clutch 15, which is a wet multi-plate clutch, when the start clutch 1 is disconnected (the excitation of the electromagnet 19 is stopped), the transmission torque continues to be input to the ball cam 17 and the cam thrust force remains. Since the pressing system 21 is pressed to the left by the remaining cam thrust force, the connection of the main clutch 13 cannot be completely released.

  However, even in such a case, the reaction force 111 that presses the pressing system 21 to the right cancels the pressing force of the main clutch 13 due to the drag torque, and the connection of the main clutch 13 (starting clutch 1) is completely completed. Release it.

  The oil viscosity increases as the temperature decreases and the drag torque increases. However, the canceling force of the fans 23 and 25 generated by collision with the oil increases as the oil temperature decreases. Even if the drag torque fluctuates as the oil temperature changes, the pressing force 13 is always effectively offset.

  If the clutch housing 11 is connected to a wheel side (automatic transmission side) torque transmission member (connection shaft 9), even if the connection of the main clutch 13 cannot be released due to the drag torque, it occurs in the main clutch 13. The slippage reduces the rotational speed of the clutch housing 11 (relative rotational speed between the fins 23 and 25 and the oil) and the cancel function is lowered. However, in the starting clutch 1, the clutch housing 11 is connected to the engine side, Since 25 always comes into contact with oil at the rotational speed on the engine side, the cancel function is kept at its maximum.

  Further, the connecting shaft 9 is provided with several axial oil passages 113 and several radial oil passages 115 communicating therewith, and a cover for preventing oil leakage from the oil passage 113 at the right end of the connecting shaft 9. 117 is attached.

  The cam ring 75 is provided with an oil passage 119 communicating with the pilot clutch 15, the clutch hub 53 is provided with oil passages 121 and 121 communicating with the main clutch 13, and the clutch housing 11 receives oil from the main clutch 13. Oil passages 123 and 123 for discharging are provided.

  The oil pressure of the oil pump is used for the shifting operation of the automatic transmission, and the oil pressurized by the oil pump is supplied to the oil passages 113 and 115, and is discharged from the oil passage 115 by the pressure and centrifugal force. The sliding bearing 95, the needle bearing 91, the thrust bearing 97, the ball cam 17, the ball bearing 67, the pilot clutch 15, the main clutch 13 and the like are sufficiently lubricated and cooled to greatly improve the durability.

  At this time, the oil passages 119 and 121 increase the amount of oil supplied to the pilot clutch 15 and the main clutch 13, respectively, and the oil passage 123 discharges oil from the main clutch 13 to the outside of the clutch housing 11 to promote oil circulation. , Improve the lubrication and cooling effect.

  Thus, the starting clutch 1 is configured.

  When the start clutch 1 is operated to release the connection as described above, the pressing force of the main clutch 13 is canceled by the reaction force of the oil applied to the fins 23 and 25 even if the drag torque is generated in the pilot clutch 15. Is completely canceled.

  Further, since the canceling force changes so as to cancel out the fluctuation of the drag torque in accordance with the temperature change of the oil, the connection release function is always kept high even if the oil state fluctuates.

  In this way, even if drag torque is generated, the start clutch 1 is completely disconnected in response to the connection release operation. For example, a creep phenomenon when the vehicle is stopped by a signal or the like is prevented.

  Further, since the automatic transmission is completely disconnected from the engine by the starting clutch 1 at the time of shifting, smooth shifting can be achieved.

  Further, since the capacity required for the synchro mechanism is reduced accordingly, the automatic transmission is made smaller and lighter, and the on-board performance is improved.

  Further, unlike the conventional example, the return spring that opposes the pressing force of the main clutch caused by the drag torque can be eliminated, so that the number of parts is reduced accordingly, and the cost is reduced.

  Therefore, it is not necessary to increase the capacity of the main clutch 13 and increase the size of the electromagnet 19 against the return spring, so that the start clutch 1 is not increased in size, weight, reduced in-vehicle performance, and increased in cost. In addition, it is possible to avoid an increase in the burden on the battery and a reduction in fuel consumption due to the enlargement of the electromagnet 19.

  Further, the fins 23 and 25 that receive the reaction force from the oil only when rotating in one direction are effective for the starting clutch 1 that rotates only in one direction by the driving force of the engine.

  Further, since the clutch housing 11 is connected to the engine side, the fins 23 and 25 are always in contact with the oil at the rotational speed on the engine side, so that the cancel function is kept at the maximum.

  Further, the fins 23 and 25 are set in the radial position (relative rotational speed with oil), the number, the inclination angle, and the size so that a desired canceling force can be obtained.

  Thus, the starting clutch 1 tunes the cancel function according to the capacity of the pilot clutch 15 (the magnitude of the drag torque), the capacity of the electromagnet 19 and the ball cam 17 (the pressing force of the main clutch 13), etc. Since the pressure can be effectively canceled, it can be widely applied to various transfers and different vehicle types.

  Further, by canceling the pressing force due to the drag torque, for example, it is possible to select oil with high viscosity, and it is possible to select a plate that is likely to generate drag torque for the pilot clutch 15. The range of plate selection is widened, and the degree of freedom in design is increased.

  Further, since the pilot clutch 15 is a multi-plate clutch type having a large friction surface area and a large torque capacity, the start clutch 1 is configured to be lightweight and compact.

  In particular, in the starting clutch 1 in which the main clutch 13 and the pilot clutch 15 are arranged in the radial direction, increasing the number of plates 71 and 73 avoids an increase in diameter while increasing the torque capacity and prevents interference with peripheral members. As a result, the vehicle mountability is improved and the load clearance of the vehicle body can be increased.

  Further, since the torque capacity can be changed by changing the number of the plates 71 and 73, adaptability to different vehicle types is further improved by adjusting the torque transmission characteristics according to the applicable vehicle type.

  Further, the capacity change (change in drag torque) of the pilot clutch 15 by adjusting the number of plates 71 and 73 can be dealt with by setting the radial positions, the number, the inclination angle, the size, etc. of the fins 23 and 25.

  In the multi-plate clutch type pilot clutch 15, drag torque is likely to be generated due to a large friction surface area. However, as described above, the influence of the drag torque is effectively eliminated by the canceling force of the fins 23 and 25.

  In this way, the starting clutch 1 can enjoy the advantages of the multi-plate clutch with the pilot clutch 15 by canceling the influence of the drag torque caused by the multi-plate clutch.

  Moreover, it is easy to provide the fins 23 and 25 in the clutch housing 11, and the structure is simple. Thus, a sufficient canceling function can be obtained with such a simple structure.

  The above embodiment (starting clutch 1) is an example in which the main clutch 13 is disposed radially outside the pilot clutch 15, and the fins 23, 25 are attached to the large-diameter clutch housing 11 disposed around the main clutch 13. In this example, the (cancellation mechanism) is provided, but the coupling and the starting clutch of the present invention are not limited to such a configuration, and can be implemented by a configuration in which the main clutch and the pilot clutch are arranged in the axial direction of each other.

  For example, in the conventional example (coupling 301) of FIG. 4, since the pressing member 319 rotates in oil, a fin is provided on the pressing member 319 to generate a canceling force in a direction opposite to the pressing force of the main clutch 307, If the cam thrust force of the ball cam 317 (the pressing force of the main clutch 307) generated by the drag torque of the pilot clutch 309 is canceled by this canceling force, the coupling 301 is connected in accordance with the release operation as in the start clutch 1. It can be canceled completely.

  As described above, since it is possible to release the coupling 301 when it is desired to release the connection, it is possible to disconnect the wheel at the intended timing during traveling and to bring the vehicle into a two-wheel drive state. Etc. can be sufficiently improved, and a reduction in fuel consumption can also be prevented.

  In the present invention, as the main clutch and the pilot clutch, any type of friction clutch such as a single plate clutch and a cone clutch may be used in addition to the multi-plate clutch.

  Also, the outer and inner plates of the main clutch and pilot clutch are suitable for the surrounding environment such as the required strength and durability for the applied coupling and start clutch, compatibility with the lubricating oil and the amount of oil, for example, , Steel, carbon, paper plate material can be selected arbitrarily.

  Furthermore, in the pilot clutch, the plate material can be selected without considering the sensitivity to the drag torque as described above.

  If a cone clutch with a small drag torque is used, the return spring can be eliminated, and the number of parts and the cost can be reduced.

  The pilot clutch operating means is not limited to an electromagnet, and may be, for example, an electric motor or a fluid pressure actuator.

  Further, either of the torque transmission members may be on the input side or on the output side.

  Further, the coupling of the present invention is not limited to the starting clutch and the drive system input / output shaft intermittent device, but can be applied to other uses such as a drive source switching device for a hybrid vehicle.

It is sectional drawing of one Embodiment. It is AA sectional drawing of FIG. It is a graph which shows that the electric current value of an electromagnet increases with drag torque. It is sectional drawing of a prior art example.

Explanation of symbols

1 Starting clutch (coupling)
9 Connecting shaft (output side torque transmission member)
11 Clutch housing (torque transmission member on the engine input side: pressing member)
13 Main clutch 15 Multi-plate pilot clutch 17 Ball cam (conversion means: cam mechanism)
19 Electromagnet (Operating means for pilot clutch 15)
21 Press system of the main clutch 13 23, 25 Fin (convex part: cancellation mechanism)

Claims (5)

The torque transmission members (11, 9) on the input side and the output side, the main clutch (13) for transmitting torque between the torque transmission members (11, 9), and the operating means (19) are intermittently operated. The pilot clutch (15), the other side member connected to the pilot clutch (15), the one side member disposed opposite to the other side member, and the one side member and the other side member. When the pilot clutch (15) is connected to the pilot clutch (15), it is actuated by receiving transmission torque, and the main clutch (13) is pressed and connected via the pressing system (21) by the conversion force generated by the transmission torque. A coupling (1) comprising a coupling mechanism,
The main clutch (13) and the pilot clutch (15) are multi-plate clutches, and the outer plates (47, 49, 71) of the main clutch (13) and the pilot clutch (15) are spline portions (55, 87), respectively. ) Is connected to the torque transmission member (11) on one side on the outer peripheral side so as to be movable in the axial direction and capable of transmitting torque , and the inner plate of the main clutch (13) ( 51) fixing the hub (53) connected to the one side member of the connecting mechanism through the spline part (57) ;
The main clutch (13) is disposed outside the pilot clutch (15) in the radial direction, and the extension part (69) that moves the pressing system (21) integrally in the pressing direction, and a pilot clutch (15 ) And the other side member of the coupling mechanism,
When the main clutch (13) is intermittently operated, a main sliding part that slides while receiving transmission torque is provided between the extension part (69) and the torque transmission member (11) on one side, and the extension part (69 ) And the outer plate (47, 49) of the main clutch (13) and between the hub (53) and each inner plate (51), the coupling (1).   The coupling (1) according to claim 1, wherein the main clutch (13) and the pilot clutch (15) are arranged in a wrapping manner in the radial direction. It is invention of Claim 2, Comprising: Between the said extension part (69) which is a press system (21) even if a connection mechanism act | operates, a pilot clutch (15), and the other side member of a connection mechanism Coupling (1) characterized in that the relative positional relationship does not change . The coupling according to any one of claims 1 to 3, wherein the operating means (19) of the pilot clutch (15) is an electromagnet . 5. The coupling according to claim 4, wherein the electromagnet (19) is attached to a rotor (85) connected to the clutch housing (11) in a non-rotating state via a bearing. (1).

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