JP2009216159A - Multi-plate clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-plate clutch capable of reducing shock or noise when the clutch is engaged and preventing friction or drag of clutch plates when the clutch is disengaged. <P>SOLUTION: The multi-plate clutch 1 includes the plurality of clutch plates 14 and a plurality of clutch disks 24 which are arranged in an alternately stacked manner. Each clutch plate 14 has a plurality of tooth parts 14a that engage with a clutch drum 10 slidably in the axial direction and relatively unrotatably in the circumferential direction. Each clutch disk 24 has a plurality of tooth parts 24a that engage with a clutch hub 20 slidably in the axial direction and relatively unrotatably in the circumferential direction. In the multi-plate clutch 1, each of the tooth parts 14a of the clutch plate 14 is divided in a plurality of split pieces 16 in the circumferential direction. By alternately projecting the split pieces 16 in the axial direction so that the split pieces 16 of the same phase of the adjacent clutch plates 14 protrude toward each other, the tooth parts 14a exhibit a buffer action in the circumferential direction and axial direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a multi-plate clutch used in an automatic transmission or the like, and more particularly, to a multi-plate clutch that can alleviate an impact and noise generated when the clutch is engaged.

  A multi-plate clutch (including a brake, the same applies hereinafter) used in an automatic transmission or the like includes, for example, a bottomed cylindrical clutch drum and a plurality of clutches engaged with the inner periphery of the clutch drum as shown in Patent Document 1. The clutch plate, a clutch hub arranged concentrically with the clutch drum, and a plurality of clutch disks that engage with the outer periphery of the clutch hub and are alternately stacked on the clutch plate. A piston mechanism for moving the clutch plate and the clutch disk in the axial direction is also provided. In such a multi-plate clutch, the clutch plate and the clutch disk are pressed and separated by a piston mechanism to engage and release the clutch, and the transmission state of the rotational power between the clutch drum and the clutch hub is switched.

  In the above-described multi-plate clutch, the clutch plate is fixed to the clutch drum, or the clutch disk is fixed to the clutch hub. Tooth portions provided on the clutch plate or the clutch disk are axial grooves provided on the clutch drum or the clutch hub. (Spline) is engaged. Thus, the clutch plate and the clutch disc are engaged with the clutch drum and the clutch hub, respectively, so as to be slidable in the axial direction and not relatively rotatable in the circumferential direction.

  By the way, in such a multi-plate clutch, when a stick-slip (impact) is generated on the friction surface of the clutch plate or the clutch disk when the clutch is engaged, the impact is transmitted to the clutch through the engaging portion of the groove portion and the tooth portion. Since it is transmitted directly to the drum and clutch hub, there is a problem of causing vibration and noise. In addition, there is a case where a minute gap is formed between the groove portion and the end surface in the circumferential direction of the tooth portion due to the processing accuracy of the part. Then, when the rotation speed of the clutch drum fluctuates, the end faces collide with each other, which causes vibration and noise.

  Further, in the clutch plate or clutch disk as described above, since the torque transmission point is mainly only at two or three tooth portions, the contact pressure at that portion becomes high, and friction (friction) occurs. There is concern about the occurrence of Therefore, it is necessary to supply a sufficient amount of lubricating oil and to strictly control the accuracy of the shape of the plate or disk. As a result, there is a problem that the structure of the multi-plate clutch is complicated and the cost is increased.

  In the multi-plate clutch as described above, the clutch plate or clutch disk may be tilted or the return stroke may be poor due to the viscous resistance of the lubricating oil in the gap between the clutch plate or clutch disk while the clutch is released. May occur. As a result, the adjacent clutch plate and the clutch disk are unnecessarily brought into contact with each other, and there is a problem that friction and dragging occur in the clutch.

In order to cope with these problems, the multi-plate clutches of Patent Document 2 and Patent Document 3 have a cushioning material such as an elastic body or a spring member interposed between the circumferential end surfaces of the clutch plate tooth portion and the clutch drum groove portion. Thus, the impact transmitted from the clutch plate to the clutch drum when the clutch is engaged is mitigated. However, since this measure adds another part to the clutch plate, the number of parts of the multi-plate clutch increases, leading to high costs. In addition, the assembly efficiency of the multi-plate clutch may be reduced. On the other hand, since the prior arts of Patent Document 2 and Patent Document 3 are not related to securing the clearance between the clutch plate and the clutch disk, they cannot prevent friction and dragging when the clutch is not engaged.
JP 2000-230574 A JP-A-9-119449 Japanese Patent Laid-Open No. 10-238565

  The present invention has been made in view of the above points, and an object of the present invention is to effectively reduce the impact and noise generated when the clutch is engaged, and to reduce the clearance between the clutch plate and the clutch disk when the clutch is not engaged. An object of the present invention is to provide a multi-plate clutch that can be secured to prevent friction and drag of the clutch.

  In order to solve the above problems, a multi-plate clutch (1) according to the present invention includes a plurality of teeth (14a) engaged with a clutch drum (10) so as to be slidable in the axial direction and not relatively rotatable in the circumferential direction. And a plurality of teeth (24a) engaged with the clutch hub (20) in an axially slidable and circumferentially non-rotatable manner, A clutch disk (24) arranged alternately and superimposed on the clutch plate (14), and at least one of the clutch plate (14) and the clutch disk (24) is at least a part of the teeth (14a). Is divided into a plurality of divided pieces (16) in the circumferential direction, and the divided pieces of the same phase between adjacent clutch plates (14) or clutch disks (24) 16) so as to protrude toward the other side from each other, the split piece (16) is characterized in that it alternately protrude in the axial direction. In addition, the code | symbol in parenthesis here has shown the code | symbol of the corresponding component of embodiment mentioned later as an example of this invention.

  According to the multi-plate clutch of the present invention, since the tooth portion of the clutch plate or the clutch disk is divided into a plurality of divided pieces in the circumferential direction, the tooth portion can be elastically deformed in the circumferential direction. Thereby, it is possible to obtain a buffering action for reducing the impact transmitted from the clutch plate to the clutch drum or the impact transmitted from the clutch disc to the clutch hub without increasing the number of parts of the multi-plate clutch. Therefore, stick-slip (impact) generated by friction of the clutch plate and the clutch disk when the clutch is engaged can be prevented from being directly transmitted to the clutch drum and the clutch hub. Further, since the torque transmission point of the clutch plate or the clutch disk is increased by the elastic deformation of the tooth portion, the contact surface pressure can be reduced. Therefore, the occurrence of friction at the torque transmission point can be suppressed. Further, since the in-phase divided pieces of adjacent clutch plates or clutch disks protrude toward each other, the clearance between the clutch plate and the clutch disk can be stably secured when the clutch is not engaged. Therefore, friction and drag when the clutch is not engaged can be effectively prevented.

  In the multi-plate clutch having the above-described configuration, the divided tooth portions of the clutch plate (clutch disc) may be formed so that adjacent ones in the circumferential direction have the same shape. In that case, when assembling the clutch plate (clutch disc) to the clutch drum (clutch hub), two types of clutch plates (clutch discs) processed so that the protruding pieces in the axial direction in the same phase are opposite to each other. ) And the two types of clutch plates (clutch discs) are alternately overlapped in the same phase, the divided pieces of the adjacent clutch plates (clutch discs) are projected toward each other. As a result, the multi-plate clutch of the present invention can be easily configured.

  Alternatively, the divided tooth portions of the clutch plate (clutch disc) may be formed so that the tooth portions adjacent to each other in the circumferential direction of the clutch plate (clutch disc) have a symmetrical shape. In that case, when the clutch plates (clutch discs) are assembled to the clutch drum (clutch hub), the clutch plates (clutch discs) are shifted in the circumferential direction by the phase of the divided tooth portions and overlapped sequentially. The split pieces of the clutch plate (clutch disc) to be projected protrude toward each other. This also makes it easy to configure the multi-plate clutch of the present invention.

  According to the multi-plate clutch of the present invention, it is possible to effectively reduce the impact and noise caused by the friction of the clutch plate and the clutch disk when the clutch is engaged, and to ensure the clearance between the clutch plate and the clutch disk when the clutch is not engaged. Thus, friction and drag of the clutch can be effectively prevented.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a side sectional view of a multi-plate clutch (wet multi-plate clutch) 1 according to an embodiment of the present invention. The multi-plate clutch 1 is disposed concentrically with respect to the clutch drum 10, a bottomed cylindrical clutch drum 10, a plurality of clutch plates 14 formed of a circular annular flat plate engaged with the inner periphery of the clutch drum 10, and the clutch drum 10. And a plurality of clutch disks 24 formed of a circular annular flat plate engaged with the outer periphery of the clutch hub 20, and the clutch plates 14 and the clutch disks 24 are alternately stacked in the axial direction. It is arranged.

  The clutch drum 10 is fixed to an annular flange 6 attached to the groove portion 8 on the outer periphery of the rotating shaft 4. An oil passage 5 extending in the axial direction is formed in the rotating shaft 4. A gear 18 for shifting is installed concentrically with the rotating shaft 4. The gear 18 is formed integrally with the clutch hub 20.

  A plurality of grooves (splines) 12 extending in the axial direction are formed on the inner peripheral surface of the clutch drum 10 at predetermined intervals in the circumferential direction, and the same number of protrusions as the grooves 12 are formed on the outer periphery of the clutch plate 14. The tooth part 14a is formed. Then, the tooth portion 14a of the clutch plate 14 is engaged with the groove portion 12 of the clutch drum 10 so as to be slidable in the axial direction and not relatively rotatable. A plurality of axially extending grooves (splines) 22 are formed on the outer peripheral surface of the clutch hub 20 at predetermined intervals in the circumferential direction, and the same number of protrusions as the grooves 22 are formed on the inner periphery of the clutch disk 24. A tooth portion 24a is formed. Then, the tooth portion 24a of the clutch disc 24 is engaged with the groove portion 22 of the clutch hub 20 so as to be slidable in the axial direction but not relatively rotatable.

  A disc-shaped clutch piston 26 is accommodated in the clutch drum 10. A cylinder chamber 28 is defined in the gap between the clutch piston 26 and the clutch drum 10. The cylinder chamber 28 and the oil passage 5 of the rotating shaft 4 communicate with each other via an oil passage 30 formed on the rotating shaft 4, oil passages 32 and 34 formed on the flange 6, and an oil passage 36 formed on the clutch drum 10. Yes. Further, the groove portion 8 is lubricated through an oil passage 42 formed in the rotary shaft 4. An annular spring receiving portion 44 is attached to the clutch drum 10, and a return spring 46 is interposed between the spring receiving portion 44 and the clutch piston 26.

  In the multi-plate clutch 1 configured as described above, when hydraulic fluid is supplied to the cylinder chamber 28 via the oil passages 30, 32, 34, 36, the clutch piston 26 is moved against the urging force of the return spring 46 as shown in FIG. Move to the left. Then, the clutch plate 14 is pressed to the left, and the clutch plate 14 and the clutch disk 24 are pressed against each other. As a result, the clutch is engaged and rotation transmission between the rotating shaft 4 and the gear 18 is possible. On the other hand, when the hydraulic oil is discharged from the cylinder chamber 28, the clutch piston 26 is moved to the right by the urging force of the return spring 46, the pressure bonding between the clutch plate 14 and the clutch disk 24 is released, and the clutch engagement is released. The

  Next, the configuration of the clutch plate 14 will be described in detail. Here, the clutch plate 14 is taken as an example, but the configuration according to the present invention described below can also be applied to the clutch disk 24.

  2A and 2B are views showing the clutch plate 14, where FIG. 2A is a side view, FIG. 2B is an enlarged view of a portion X in FIG. 2A, and FIG. ) Is a view taken in the direction of arrow D in (b), and (e) is a diagram showing a modified example of the cut 15 described later. In FIG. 4D, other adjacent clutch plates 14 and clutch disks 24 are also shown for the sake of explanation. As shown in FIG. 2B, the clutch plate 14 is provided with a notch 15 in a predetermined tooth portion 14a, thereby dividing the tooth portion 14a into a plurality of divided pieces 16 in the circumferential direction. Thereby, the tooth part 14a becomes elastically deformable in the circumferential direction. The cut 15 is linearly provided in the center direction (radial direction) of the clutch plate 14 from the outer peripheral end face of the tooth portion 14a. In addition, as shown to the same figure (e), it is good to provide the hollow part 15a for avoiding stress concentration in the root part of the cut | notch 15. The recess 15a is preferably a groove having a circular cross section as shown in the drawing, but may have other shapes as long as the stress can be dispersed. In the example shown in FIG. 2, the tooth portion 14 a is divided into two divided pieces 16 by one notch 15. The tooth portions 14a to be divided are preferably a plurality of equally spaced teeth among all the tooth portions 14a, and the specific number is preferably at least 4 (90 degree intervals) or more, as will be described later. Any number is acceptable.

  Further, as shown in FIG. 2C, the divided pieces 16 are slightly bent so as to protrude alternately in the rotation axis direction. Then, as shown in FIG. 2D, the clutch plates 14 are overlapped so that the in-phase divided pieces 16 of the adjacent clutch plates 14 protrude toward each other. Thereby, when the clutch is not engaged, the divided pieces 16 of the adjacent clutch plates 14 come into contact with each other, so that a predetermined clearance can be secured between the clutch plates 14. When the clutch is engaged, the interval between the clutch plates 14 is narrowed due to the elastic deformation of the divided pieces 16, and the clutch plates 14 are pressure-bonded to the clutch disk 24.

  Here, a procedure for stacking a plurality of clutch plates 14 on the clutch drum 10 will be described. FIG. 3 is a diagram for explaining the procedure. Here, the case where the tooth part 14a divided | segmented into the two division | segmentation piece 16 is provided in four places of equal intervals is demonstrated. In the figure, for the purpose of explanation, the divided pieces 16 protruding in the same direction in the axial direction are shown in black. There are two procedures for overlapping the clutch plates 14 shown in FIGS. 3 (a) and 3 (b). In the first procedure shown in FIG. 3A, first, when dividing the tooth portion 14a of the clutch plate 14-1, two divided pieces 16 belonging to one tooth portion 14a are opposite to each other in the axial direction. It processes so that it may protrude, and it processes so that the shape (projection direction) of the adjacent divided tooth part 14a may become mutually symmetrical. A plurality of clutch plates 14-1 processed in this way are shifted by the phase of the divided tooth portion 14 a (in this case, 90 degrees), and the necessary number of sheets are overlapped.

  In the second procedure shown in FIG. 3B, when the tooth portion 14a of the clutch plate 14-2 is divided, the two divided pieces 16 belonging to one tooth portion 14a protrude in opposite directions in the axial direction. And processing is performed so that the adjacent divided tooth portions 14a have the same shape. Further, another clutch plate 14-3 processed so that each divided piece 16 protrudes in the opposite direction in the axial direction is prepared for the clutch plate 14-2. Then, these two types of clutch plates 14 are alternately overlapped in the same phase as required.

  In any of the above procedures, as shown in FIG. 3C, the clutch plates 14 are overlapped with each other in such a state that the in-phase divided pieces 16 of the adjacent clutch plates 14 protrude toward each other.

  As described above, in the multi-plate clutch 1 of the present embodiment, the tooth portion 14a of the clutch plate 14 is divided into a plurality of divided pieces 16, so that the tooth portion 14a is elastically deformed in the circumferential direction. As a result, it is possible to provide a buffering action that reduces the impact transmitted from the clutch plate 14 to the clutch drum 10 without increasing the number of parts of the multi-plate clutch 1. Therefore, stick-slip (impact) generated on the friction surface of the clutch plate 14 when the clutch is engaged can be prevented from being directly transmitted to the clutch drum 10. The buffer action by the divided pieces 16 can be exhibited both when the rotation of the clutch plate 14 is accelerated and decelerated.

  Further, since the split piece 16 pressed by the circumferential end face of the groove 12 of the clutch drum 10 is elastically deformed, the torque transmission point of the clutch plate 14 is increased, so that the contact surface pressure can be reduced. Therefore, the occurrence of friction at the torque transmission point can be suppressed. As a result, demands such as supply of lubricating oil to the clutch plate 14 and accuracy control of the shape of the clutch plate 14 are alleviated, and the configuration of the multi-plate clutch 1 can be simplified and the manufacture thereof can be facilitated. it can.

  Further, in this multi-plate clutch 1, the split pieces 16 of the same phase of the adjacent clutch plates 14 protrude toward each other, so that the clearance between the clutch plate 14 and the clutch disk 24 is stabilized by the split pieces 16. Can be secured. Therefore, unnecessary contact between the clutch plate 14 and the clutch disk 24 when the clutch is not engaged can be effectively avoided, and generation of friction and dragging of the clutch can be prevented. Further, since the elastic parts normally used for separating the clutch plate 14 and the clutch disk 24 are not required, the number of parts of the multi-plate clutch 1 can be reduced. Furthermore, since the surface area of the clutch plate 14 is increased by providing the notches 15 in the tooth portions 14a of the clutch plate 14, an improvement in the cooling efficiency of the clutch plate 14 can be expected.

  FIG. 4 is a diagram showing a specific example of the number and shape of the divided tooth portions 14a. As shown in FIG. 4A, the divided tooth portions 14a are set to four at intervals of 90 degrees, and as shown in FIG. As shown in (), all the tooth portions 14a may be divided. Although not shown, every two or more tooth portions 14a may be divided. If the number of the divided tooth portions 14a is changed, the buffering action on the clutch drum 10 and the clearance amount between the adjacent clutch plates 14 can be arbitrarily adjusted. Further, in addition to forming the divided tooth portions 14a to all have the same size, for example, as shown in FIG. 4D, the protruding dimensions (height dimensions) are regular (in this case, every other piece 14a). ) May be different. In this way, when the plurality of clutch plates 14 are overlapped, they can be prevented from being overlapped in the wrong order or phase, and erroneous assembly can be reliably prevented.

  FIG. 5 is a diagram illustrating another configuration example of the divided piece 16. By changing the shape and the number of the divided pieces 16, the buffering action on the clutch drum 10 and the clearance amount between the adjacent clutch plates 14 can be arbitrarily adjusted. FIG. 5A shows an example in which the position or number of the cuts 15 is adjusted. If the position in the circumferential direction in which the cut 15 is provided is changed, the elastic force of the divided piece 16 can be arbitrarily adjusted. That is, if the circumferential width P of the divided piece 16 is reduced, the elastic force of the divided piece 16 is reduced, and if the width P is increased, the elastic force of the divided piece 16 is increased.

  In this case, in addition to making one notch 15 in one tooth portion 14a, it is also possible to insert two or more notches 15 and divide one tooth portion 14a into three or more divided pieces 16. . For example, as shown in FIG. 5 (a), if the tooth portion 14a is divided into three divided pieces 16, the width of the divided pieces 16 on both sides can be set arbitrarily, so that the elastic force of the divided pieces 16 can be adjusted. It will be easier. In this case, as shown in the figure, the divided pieces 16 on both sides are alternately projected in the axial direction, while the central divided piece 16 is not protruded in the axial direction and has a shape as it is. In addition, although the case where the cut 15 was linearly shown here was shown, the cut 15 can also be put in curvilinear form, such as S shape, and a bending line form besides linear form.

  Further, the elastic force of the split piece 16 can be adjusted by changing the plate thickness of the clutch plate 14. When the plate thickness Q shown in FIG. 5A is reduced, the elastic force in the circumferential direction and the axial direction by the divided pieces 16 is reduced, so that the buffering action on the clutch drum 10 and the clearance between the adjacent clutch plates 14 are reduced. If the plate thickness Q is reduced and the plate thickness Q is increased, the elastic force of the divided piece 16 is increased, and the buffer action and clearance are increased.

  FIG. 5B shows an example in which the angle of the cut 15 is adjusted. If the notch 15 is provided with an angle R with respect to the center direction of the clutch plate 14 (inclined state), the elastic force in the circumferential direction by the divided piece 16 changes, and the buffering action changes. FIG. 5C shows an example in which the axial projecting dimension of the split piece 16 is adjusted. If the protruding dimension S in the axial direction of the split piece 16 is increased, the clearance between the clutch plates 14 when the clutch is not engaged is increased, and if the protruding dimension S is decreased, the clearance is decreased.

  FIG. 5D shows an example in which the width of the circumferential direction or the axial direction is adjusted by changing the shape of the split piece 16. If the recess 17a is provided on the end face in the axial direction of the split piece 16 to reduce the axial width dimension T, the elastic force in the axial direction by the split piece 16 is reduced, and the clearance between the adjacent clutch plates 14 is reduced. Further, if the recess 17b is provided on the circumferential end face of the divided piece 16 to reduce the circumferential width dimension U, the circumferential elastic force by the divided piece 16 is reduced, and the buffering action on the clutch drum 10 is reduced. Get smaller. Furthermore, the elastic force of the division | segmentation piece 16 can be arbitrarily adjusted also by selecting the material of the tooth | gear part 14a suitably.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. It should be noted that any shape, structure, or material not directly described in the specification and drawings is within the scope of the technical idea of the present invention as long as the effects and advantages of the present invention are exhibited.

  As described above, the structure in which the tooth portion 14a according to the present invention is divided into the plurality of divided pieces 16 is not limited to the clutch plate 14 fixed to the clutch drum 10, but to the clutch disk 24 fixed to the clutch hub 20. Is also applicable. When applied to the clutch disk 24, although not shown, the tooth portion 24a formed on the inner periphery of the clutch disk 24 is divided into a plurality of parts. The present invention can be applied not only to a wet multi-plate clutch but also to a wet multi-plate brake. Furthermore, it can also be applied to dry multi-plate clutches and brakes.

1 is a side sectional view showing a multi-plate clutch according to an embodiment of the present invention. It is a figure which shows a clutch plate, (a) is a side view, (b) is an enlarged view of the X part of (a), (c) is a C arrow view of (b), (d) is D of (b). An arrow view and (e) are figures which show the modification of a notch | incision. It is a figure for demonstrating the procedure which overlaps a some clutch plate. It is a figure which shows the specific examples, such as the arrangement | sequence and shape of a divided | segmented tooth part. It is a figure which shows the other structural example of a division piece.

Explanation of symbols

1 Multi-plate clutch 4 Rotating shaft 5 Oil passage 6 Flange 8 Groove portion 10 Clutch drum 12 Groove portion (Spline)
14 Clutch plate 14a Tooth part 16 Split piece 18 Gear 20 Clutch hub 22 Groove part (spline)
24 Clutch disc 24a Tooth portion 26 Clutch piston 28 Cylinder chambers 30, 32, 34, 36 Oil passage 42 Oil passage 44 Spring receiving portion 46 Return spring

Claims (3)

A clutch plate having a plurality of teeth that are slidable in the axial direction with respect to the clutch drum and are relatively non-rotatable in the circumferential direction;
A plurality of teeth that are slidable in the axial direction with respect to the clutch hub and that are relatively non-rotatable in the circumferential direction, and a clutch disk that is alternately overlapped with the clutch plate,
At least one of the clutch plate or the clutch disk is divided into a plurality of divided pieces in the circumferential direction, and the divided pieces having the same phase between adjacent clutch plates or clutch disks. The segment pieces project alternately in the axial direction so that they project toward each other.
A multi-plate clutch characterized by that.   2. The multi-plate clutch according to claim 1, wherein the divided tooth portions are adjacent to each other in the circumferential direction and are formed in the same shape.   2. The multi-plate clutch according to claim 1, wherein the divided tooth portions are formed in a symmetrical shape adjacent to each other in the circumferential direction.

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