JP2012077842A - Synchronizer of transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress or prevent contact between an inner diameter-side cone face 431 (441) of a synchronizer ring 43 (44) and an outer diameter-side cone face 211 (311) of a transmission gear 21 (31) when the synchronizer ring 43 (44) is in a state in which it can be idled, without adding a new component different from an existing constituent element in the synchronizer 4 of a transmission.SOLUTION: There is provided a restriction portion for restricting the axial displacement amount of the synchronizer ring 43 (44) relative to a shifting key 45. The restriction portion is composed of an arm 454 (455) provided to the shifting key 45 so as to be extended to a synchronizer ring 43 (44), and a depression 433 (443) which is provided on the outer circumference of the synchronizer ring 43 (44) so as to be depressed inward in the radial direction and to which the leading end side of the arm 454 (455) is engaged.

Description

  The present invention relates to a transmission synchronization device mounted on a vehicle or the like.

  2. Description of the Related Art Conventionally, some transmissions mounted on vehicles and the like are configured to transmit power by selecting an appropriate transmission gear by operating a shift lever by a driver. At the time of gear shifting, the gears are smoothly shifted by synchronizing the rotation speeds of the two rotating elements rotated at different rotation speeds with a synchronization device.

  In the neutral state of the transmission, since the synchronizer ring can rotate freely, the synchronizer ring is displaced in the axial direction so that the inner diameter side cone surface and the shift disposed on one side in the axial direction. It is known that the outer diameter side cone surface of the gear may come into contact with each other, thereby causing a drag load.

  In order to suppress generation | occurrence | production of such drag load, the technique as shown, for example in patent documents 1 and 2 is proposed.

  In the conventional example according to Patent Document 1, an appropriate number of synchro keys arranged at equal circumferential intervals among a plurality of synchro keys are used as drag preventing members (pull keys) (see paragraph 0026, FIG. 1). This drag preventing member (pull key) has a shape in which an engagement portion extending at a right angle inward in the radial direction is provided on one end side in the axial direction of the belt-like plate. By engaging the engagement portion of the drag preventing member with an engagement portion such as a circumferential groove provided on the outer diameter side of the synchronizer ring on one axial direction, By restricting the synchronizer ring from being displaced toward the transmission gear on one side in the axial direction, the inner diameter side cone surface of the synchronizer ring is prevented from coming into contact with the outer diameter side cone surface of the transmission gear ( (See paragraphs 0027 and 0030).

  In the conventional example according to Patent Document 2, spring members are respectively provided between a plurality of synchronizer keys and synchronizer rings on both axial sides (see paragraph 0034 and FIG. 1). This spring member urges the synchronizer rings on both sides away from the pieces (transmission gears) arranged on one side in the axial direction, so that the synchronizers on both sides can be rotated when the synchronizer rings can rotate freely. The pressing surface (inner diameter side cone surface) of the ring is prevented from coming into contact with the pressed surfaces (outer diameter side cone surfaces) of the pieces on both sides (see paragraphs 0036 and 0037, FIG. 3).

JP 2010-31999 A JP 200476764 A

  In the conventional example according to Patent Document 1, an appropriate number of synchro keys arranged at equal circumferential intervals among a plurality of synchro keys are used as drag preventing members (pull keys), so that the number of additional parts is small. However, since the engaging portion of the pull key, which is the drag preventing member, is a rigid body portion extending radially inwardly at a right angle, when engaging with the engaging portion formed by the circumferential groove of the transmission gear, The pull key must be applied inward in the radial direction from the outer diameter side of the gear, and it is feared that the assemblability is poor in consideration of the assembly work of the synchro key in addition to this pull key.

  Further, in the case of the conventional example according to Patent Document 1, the drag preventing member suppresses contact between one synchronizer ring arranged on one side of the synchro key in the axial direction and the transmission gear arranged on one side in the axial direction. Therefore, in the case where the synchronizer rings are arranged on both sides in the axial direction of the synchronizer key, the drag preventing member cannot restrict the axial displacement of both synchronizer rings. Therefore, any one of the synchronizer rings is displaced in the axial direction, and the possibility that the inner diameter side cone surface comes into contact with the outer diameter side cone surface of the transmission gear arranged on one side in the axial direction is increased.

  In the conventional example according to Patent Document 2 described above, movement of the synchronizer rings on both sides in the axial direction of the plurality of synchronizer keys is regulated, but each of the synchronizer rings is independent between the plurality of synchronizer keys and the synchronizer rings on both sides in the axial direction. Since the spring member made up of the parts is arranged, there is a concern that the equipment cost will increase, such as an increase in the number of parts and an increase in the trouble of assembling.

  In view of such circumstances, the present invention provides an inner diameter of the synchronizer ring when the synchronizer ring can rotate without adding a new component separate from existing components in the transmission synchronization device. The object is to suppress or prevent contact between the side cone surface and the outer diameter side cone surface of the transmission gear.

  A transmission synchronization device according to the present invention includes: a clutch hub that is externally mounted on a rotary shaft so as to be integrally rotatable; and a transmission gear that is externally rotated on one side of the clutch hub on the rotary shaft. A synchronizer ring having an inner diameter side cone surface fitted to the outer diameter side cone surface and having external teeth, a sleeve spline-fitted to the outer periphery of the clutch hub, and a circumference around the circumference of the clutch hub Shifting having an engaging portion that is positioned in the direction and incorporated in a state that can be displaced in the axial direction, and that is engaged with a key groove provided in the middle in the axial direction of the inner diameter side spline of the sleeve. And a restricting portion for restricting an axial displacement amount of the synchronizer ring with respect to the shifting key. An arm provided on the shifting key so as to extend toward the synchronizer ring, and a recess provided on the outer periphery of the synchronizer ring so as to be recessed inward in the radial direction so that the distal end side of the arm is engaged. It is characterized by being.

  In this configuration, when the sleeve receives a shift operation to be slid to the synchronizer ring side, the inner diameter side cone surface of the synchronizer ring is pressed against the outer diameter side cone surface of the transmission gear, thereby the sleeve and the sleeve While synchronizing the rotational speeds of the synchronizer ring and the transmission gear, by engaging the outer diameter side spline of the sleeve with the outer teeth of the transmission gear, the transmission gear is coupled to the rotary shaft so as to be integrally rotatable. Operate.

  Since the amount of axial displacement of the synchronizer ring relative to the shifting key is regulated, the inner diameter side cone surface of the synchronizer ring and the outer diameter side of the transmission gear in the neutral state, that is, the state where the synchronizer ring can rotate freely. The contact with the cone surface can be suppressed or prevented. Therefore, friction loss and wear can be reduced, which is advantageous in improving fuel consumption and durability.

  In addition, the existing shift key and synchronizer ring are simply provided with a restricting part, and no new components are added separately from the existing components as in the conventional example. It becomes possible to do.

  Preferably, a second speed change gear is provided on the other side of the clutch hub, a second synchronizer ring is also provided on the outer diameter side cone surface of the second speed change gear, and the sleeve is either in the axial direction. And a second restricting portion for restricting an axial displacement amount of the second synchronizer ring with respect to the shifting key. The restricting portion is provided on the shifting key so as to extend toward the second synchronizer ring, and provided on the outer periphery of the second synchronizer ring so as to be recessed radially inward. It is comprised by the 2nd dent with which the front end side of a 2nd arm is engaged.

  In this way, it is specified that the transmission gears are arranged on both sides in the axial direction of the clutch hub, and that the restriction unit for limiting the axial displacement amount of the two synchronizer rings with respect to the shifting key is specified. Can do.

  Preferably, the shifting key has a body that can accommodate a lock ball and a coil spring, and the coil spring is elastically restored by being incorporated in a compressed state in the body. Is partially protruded from the upper opening of the body, and the lock ball is disposed at a neutral position where the sleeve is not meshed with the transmission gear, and the key of the inner diameter side spline of the sleeve. The coil spring is engaged with the elastic restoring force of the coil spring, and when the sleeve is slid in one axial direction and meshed with the transmission gear, the coil spring is further compressed to come out of the key groove It is.

  Here, the configuration with a lock ball is specified as the shifting key.

  Preferably, the arm has elasticity so as to bend in the radial direction, and a substantially V-shaped locking piece that bends inward in the radial direction and then outwards in the radial direction is provided on the distal end side thereof. Provided, and the locking piece is engaged with the recess.

  Here, the nature of the arm and the shape of the locking piece are specified, and the form of engagement of the locking piece with the recess is specified. In this case, when engaging the locking piece of the arm of the shifting key with the recess as the restriction portion of the transmission gear, if the locking piece is pressed against the opening of the recess, the arm is once bent radially outward. Then, after overcoming the opening of the recess, the arm is elastically restored, and the locking piece enters the recess. Thus, when engaging the locking piece of the arm with the recess, the arm is elastically deformed so as to bend in the radial direction, so that the shifting key and the synchronizer ring are relatively easy to assemble when assembling the synchronizer. It becomes possible to connect to.

  The synchronizer for a transmission according to the present invention can be configured such that when the synchronizer ring can rotate freely without adding new components separate from existing components, the inner cone surface of the synchronizer ring and the transmission gear It becomes possible to suppress or prevent contact with the outer diameter side cone surface.

1 is a cross-sectional view showing a schematic configuration of an embodiment of a transmission synchronization device according to the present invention. It is a side view which shows the positional relationship of the clutch hub of FIG. 1, a shifting key, and a sleeve. It is a top view which shows the positional relationship of the shifting key of FIG. 1, a synchronizer ring, and the gear piece of a 1st transmission gear. It is a figure which expands and shows the upper half and lower half of FIG. It is a figure which shows the state which isolate | separated the locking piece of the shifting key of FIG. 1, and the dent of the synchronizer ring. It is a figure which shows the process in which the locking piece of a shifting key is locked to the dent of a synchronizer ring from the state of FIG. It is a figure which shows the state which latched the locking piece of the shifting key to the dent of the synchronizer ring from the state of FIG. It is a figure which expands and shows the upper half of FIG. It is a figure which shows a synchronous state when a shift operation is carried out from the state of FIG. FIG. 10 is a diagram showing a state when the shift operation is completed from the state of FIG. 9.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the accompanying drawings.

  1 to 10 show an embodiment of the present invention. In the figure, reference numeral 1 denotes a rotating shaft, and two transmission gears 2 and 3 are attached to the rotating shaft 1 via cage-and-roller type rolling bearings (reference numerals omitted) so as to be relatively rotatable. In this embodiment, the first transmission gear 2 on the right side in the figure is an odd gear stage, and the second transmission gear 3 on the left side in the figure is an even gear stage.

  Gear pieces 21 and 31 are spline-fitted to the first and second transmission gears 2 and 3. The outer peripheral surfaces of the small-diameter portions of the gear pieces 21 and 31 are cone surfaces 211 and 311 that gradually reduce in diameter toward the tip.

  A synchronization device 4 is provided between the first and second transmission gears 2 and 3. The synchronizer 4 illustrated in this embodiment includes a clutch hub (also called a synchronizer hub) 41, a sleeve 42, two synchronizer rings 43 and 44, a plurality of (for example, three) shifting keys 45, and the like.

  The clutch hub 41 has a spline 411 provided on the inner periphery thereof, and can be integrally rotated with the rotary shaft 1 by being fitted to the spline 11 provided in a predetermined axial region on the outer periphery of the rotary shaft 1. It is in a state and slidable in the axial direction.

  The sleeve 42 has a spline 421 provided on the inner periphery thereof, and can be integrally rotated with the rotary shaft 1 via the clutch hub 41 by being fitted to a spline 412 provided on the outer periphery of the clutch hub 41. It is in a state and slidable in the axial direction. The sleeve 42 is slid in one of the axial directions of the rotary shaft 1 by a shift operation of a shift fork (not shown) by the driver.

  The first and second synchronizer rings 43 and 44 are members for synchronizing the rotations of the gear pieces 21 and 31 of the first and second transmission gears 2 and 3 and the clutch hub 41.

  The inner peripheral surface of the first synchronizer ring 43 is a cone surface 431 that is fitted to the outer diameter side of the outer diameter side cone surface 211 of the gear piece 21 of the first transmission gear 2. On the inner periphery of the second synchronizer ring 44, a cone surface 441 is provided to be fitted to the outer diameter side of the outer diameter side cone surface 311 of the gear piece 31 of the second transmission gear 3. On the outer periphery of both the synchronizer rings 43, 44, there is provided a small diameter portion in which the outer cylinder portion of the clutch hub 41 is fitted through a predetermined gap, and meshes with the inner diameter side spline 421 of the sleeve 42 as necessary. External teeth 432 and 442 are provided.

  When the first synchronizer ring 43 is pressed, for example, toward the first transmission gear 2 by the shift operation of the sleeve 42, the inner diameter side cone surface 431 of the first synchronizer ring 43 is on the outer diameter side of the gear piece 21 of the first transmission gear 2. It is pressed against the cone surface 211. On the other hand, when the second synchronizer ring 44 is pressed, for example, toward the second speed change gear 3 by the shift operation of the sleeve 42, the inner diameter side cone surface 441 of the second synchronizer ring 44 is outside the gear piece 31 of the second speed change gear 3. It is in pressure contact with the radial cone surface 311.

  The shifting key 45 is accommodated in notches 413 provided at several places (for example, three places) on the circumference of the clutch hub 41. The notches 413 are recessed radially inward in the clutch hub 41 and open to both axial sides.

  The shifting key 45 includes a body 451, a lock ball 452, a coil spring 453, and the like.

  The body 451 is formed in a shape that can accommodate the lock ball 452 and the coil spring 453, for example, by press-molding a metal plate. The coil spring 453 partially protrudes the lock ball 452 from the upper opening of the body 451 with an elastic restoring force by being incorporated in the body 451 in a compressed state.

  When the sleeve 42 is disposed at a neutral position where the sleeve 42 is not meshed with the gear pieces 21 and 31 of the first and second transmission gears 2 and 3, the lock ball 452 is moved by the elastic restoring force of the coil spring 453. Although engaged with a key groove 422 provided in the middle of the inner diameter side spline 421 in the axial direction, the sleeve 42 is slid in one or the other in the axial direction, and the gear pieces 21 of the first and second transmission gears 2 and 3, The coil spring 453 is further compressed when it is engaged with the external teeth 212 and 312 of the 31 so as to come out of the key groove 422. The lock ball 452 corresponds to the engaging portion described in the claims.

  Next, the basic operation of the synchronization device 4 will be described. For example, when the sleeve 42 is stopped at the neutral position shown in FIG. 8, it is in a neutral state in which the rotating shaft 1 and the first and second transmission gears 2 and 3 rotate relative to each other. In this neutral state, the inner diameter side cone surfaces 431 and 441 of the first and second synchronizer rings 43 and 44 are separated from the outer diameter side cone surface 211 of the gear piece 21 of the second transmission gear 2. The synchronizer rings 43 and 44 can be rotated.

  When the sleeve 42 is moved in the X direction in FIG. 8 in response to a shift operation from this neutral state, the sleeve 42 presses the first synchronizer ring 43 toward the gear piece 21 side of the first transmission gear 2 in the initial stage. become. As a result, as shown in FIG. 9, the inner diameter side cone surface 431 of the first synchronizer ring 43 is brought into contact with the outer diameter side cone surface 211 of the gear piece 21, and the frictional force between the both cone surfaces 431, 211. That is, the first synchronizer ring 43 and the first transmission gear 2 are gradually rotated synchronously by the relative rotational torque.

  Thus, when the shift operating force is further applied to the sleeve 42, the shifting key 45 is moved together with the sleeve 42, and the body 45 of the shifting key 45 comes into contact with the gear piece 21 of the first transmission gear 2, The movement of the shifting key 45 is stopped, and as shown in FIG. 10, the lock ball 452 of the shifting key 45 is disengaged from the key groove 422 of the sleeve 42, and the inner diameter side spline 421 of the sleeve 42 is moved to the first sync. The external teeth 432 of the kniter ring 43 and the external teeth 212 of the gear piece 21 of the first transmission gear 2 are sequentially meshed with each other, and the clutch hub 41 and the first transmission gear 2 are rotated together.

  As a result, when the rotary shaft 1 is used as an input shaft, the rotational power of the rotary shaft 1 is transmitted to the gear piece 21 and the first transmission gear 2 via the clutch hub 41 and the sleeve 42. When the shaft 1 is an output shaft, the rotational power of the first transmission gear 2 and the gear piece 21 is transmitted to the rotary shaft 1 via the sleeve 42 and the clutch hub 41.

  From this state, the sleeve 42 is moved in the opposite direction, and the inner diameter side spline 421 of the sleeve 42 is removed from the external teeth 212 of the gear piece 21 of the first transmission gear 2 and the external teeth 432 of the first synchronizer ring 43. When the position shown in FIG. 8 is restored, the neutral state is restored.

  On the other hand, when the sleeve 42 is moved in the Y direction in FIG. 8 in response to a shift operation from this neutral state, the sleeve 42 presses the second synchronizer ring 44 toward the gear piece 31 side of the second transmission gear 3 in the initial stage. Will do. Thereby, although not shown, the inner diameter side cone surface 441 of the second synchronizer ring 44 is brought into contact with the outer diameter side cone surface 311 of the gear piece 31, and the frictional force between the two cone surfaces 441, 311, that is, The second synchronizer ring 44 and the second transmission gear 3 are gradually rotated synchronously by the relative rotational torque.

  Thus, when the shift operating force is further applied to the sleeve 42, the shifting key 45 is moved together with the sleeve 42, and the body 45 of the shifting key 45 comes into contact with the gear piece 31 of the second transmission gear 3, While the movement of the shifting key 45 is stopped and not shown, the lock ball 452 of the shifting key 45 is disengaged from the key groove 422 of the sleeve 42 and the inner diameter side spline 421 of the sleeve 42 becomes the second synchronizer. The outer teeth 442 of the ring 44 and the outer teeth 312 of the gear piece 31 of the second transmission gear 3 are sequentially engaged with each other, so that the clutch hub 41 and the second transmission gear 3 rotate together.

  As a result, when the rotary shaft 1 is an input shaft, the rotational power of the rotary shaft 1 is transmitted to the gear piece 31 and the second transmission gear 3 via the clutch hub 41 and the sleeve 42, while rotating When the shaft 1 is an output shaft, the rotational power of the second transmission gear 3 and the gear piece 31 is transmitted to the rotary shaft 1 via the sleeve 42 and the clutch hub 41.

  Next, the axial displacement amount of the first and second synchronizer rings 43 and 44 with respect to the shifting key 45 is regulated in the neutral state, that is, the state where the first and second synchronizer rings 43 and 44 can rotate freely. I will explain in detail.

  The first and second synchronizer rings 43 and 44 are provided with first and second recesses 433 and 443 which are recessed radially inward from the outer peripheral surface at the circumferential positions (the same number as the shifting key 45). First and second arms 454 and 455 are provided on both sides of each body 451 of the three shifting keys 45, respectively. In this embodiment, the first and second arms 454 and 455 are in pairs.

  The first arm 454 protrudes straight in parallel with the axial direction toward the first synchronizer ring 43 side, and a locking piece engageable with the first recess 433 of the first synchronizer ring 43 at the tip side thereof. 456 is provided. The second arm 455 protrudes straight in parallel with the axial direction toward the second synchronizer ring 44 side, and the front end side thereof is engageable with the second recess 443 of the second synchronizer ring 44. A stop piece 457 is provided.

  The first and second arms 454 and 455 have elasticity so that they can bend in the radial direction. The locking pieces 456 and 457 are once bent radially inward toward the distal end and then bent radially outward. When viewed from one side in the circumferential direction on the upper half side, the locking pieces 456 and 457 are substantially V-shaped. It has become. The sharp portions of the locking pieces 456 and 457 are engaged with the first and second recesses 433 and 443. The locking pieces 456 and 457 may be substantially U-shaped.

  In the state where the sharp portions of the locking pieces 456 and 457 are engaged with the first and second recesses 433 and 443, the locking pieces 456 and 457 are appropriately arranged in the axial direction in the first and second recesses 433 and 443, respectively. Appropriate axial play is provided between the two so that they can be displaced.

  By the way, in this embodiment, the body 451 is manufactured by press-molding a metal plate as described above. Therefore, the arms 454 and 455 and the locking pieces 456 and 457 as described above are attached to the body 451. Even if they are provided integrally, they can be manufactured relatively easily.

  For example, when assembling the synchronization device 4, first, as shown in FIG. 5, for example, the distal end side of the locking piece 456 (or 457) of the first arm 454 (or the second arm 455) of the shifting key 45. When the inner end outer diameter side corner of the first synchronizer ring 43 (or the second synchronizer ring 44), that is, the opening of the first recess 433 (or the second recess 443) is pressed against the slope, and further pressed, As shown in FIG. 6, the first arm 454 (or the second arm 455) is bent outward in the radial direction, and the pointed portion of the locking piece 456 (or 457) is the opening of the first recess 433 (or the second recess 443). When the first arm 454 (or the second arm 455) is elastically restored as shown in FIG. 7, the locking piece 456 (or 457) is sharpened. Min so that the entering into the first recess 433 (or the second recess 443) of the first synchronizer ring 43 (or the second synchronizer ring 44).

  In this manner, the locking pieces 456 and 457 of the first and second arms 454 and 455 of the shifting key 45 are engaged with the first and second recesses 433 and 443 of the first and second synchronizer rings 43 and 44, respectively. When combined, the shifting key 45 and the first and second synchronizer rings 43 and 44 are connected via a predetermined axial play. Therefore, the amount of axial displacement of the first and second synchronizer rings 43 and 44 relative to the shifting key 45 is restricted.

  With this configuration, for example, as shown in FIG. 8, the synchronizer ring 43 with respect to the shifting key 45 in the neutral state, that is, the state in which the synchronizer rings 43, 44 on both sides in the axial direction of the clutch hub 41 can rotate freely. The amount of axial displacement of 44 can be regulated. Therefore, in the neutral state, the inner diameter side cone surfaces 431 and 441 of the two synchronizer rings 43 and 44 and the outer diameter side cone surfaces 211 and 311 of the gear pieces 21 and 31 of the first and second transmission gears 2 and 3 come into contact with each other. The possibility becomes low.

  Further, for example, in the shift operation process described with reference to FIGS. 8 to 10, when the shifting key 45 is slid to the first synchronizer ring 43 (or the second synchronizer ring 44) together with the sleeve 42, this shifting is performed. The second synchronizer ring 44 (or the first synchronizer ring 43) is pulled by the key 45 in the same direction as the sliding direction. Therefore, the inner diameter side cone surface 441 (or 431) of the second synchronizer ring 44 (or first synchronizer ring 43) is the outer diameter of the gear piece 31 (or 21) of the second transmission gear 3 (or first transmission gear 2). The possibility of coming into contact with the side cone surface 311 (or 211) can be reduced.

  By the way, the above-described shifting key 45 and the two synchronizer rings 43 and 44 can be connected to each other, and the restriction operation of the axial displacement amount of the synchronizer rings 43 and 44 with respect to the above-described shifting key 45 is established. In addition, since the dimensions of the thrust gap of each part are set as follows, the description will be given with reference to FIG.

  (A) The thrust gap between the inner diameter side cone surface 431 of the first synchronizer ring 43 and the outer diameter side cone surface 211 of the gear piece 21 of the first transmission gear 2 is defined as “M1R”, and the inner diameter side cone surface of the second synchronizer ring 44 A thrust gap between the gear 441 and the outer cone surface 311 of the gear piece 31 of the second transmission gear 3 is defined as “M1L”.

  (B) The thrust gap (so-called invalid stroke) between the body 451 of the shifting key 45 and the first synchronizer ring 43 is “M2R”, and the thrust gap (so-called “so-called invalid stroke”) between the body 451 of the shifting key 45 and the second synchronizer ring 44. Invalid stroke) is set to “M2L”.

  (C) The thrust gap (so-called regulation shape gap) between the first recess 434 and the locking piece 456 of the first arm 454 is “M3R”, and the thrust between the second recess 444 and the locking piece 457 of the second arm 455 is A gap (so-called regulated shape gap) is defined as “M3L”.

  (D) The thrust gap between the clutch hub 41 and the first synchronizer ring 43 is “M4R”, and the thrust gap between the clutch hub 41 and the second synchronizer ring 44 is “M4L”.

  Then, as shown in FIG. 4, M1R <M2R <M3R and M1L <M2L <M3L are set in a state where the sleeve 42 is disposed at the neutral position. Note that M1R = M1L, M2R = M2L, and M3R = M3L are set. Further, M2R <(M4L-M1L), that is, M1L <(M4L-M2R), M2L <(M4R-M1R), that is, M1R <(M4R-M2L) is set.

  With this setting, for example, in the process of shifting the sleeve 42 from the neutral state to the first transmission gear 2 side as described with reference to FIGS. 8 to 10, the inner diameter side cone surface of the first synchronizer ring 43. 431 is brought into pressure contact with the outer diameter side cone surface 211 of the gear piece 21 of the first transmission gear 2 so that the thrust gap M1R is reduced to zero, and then the body 451 of the shifting key 45 contacts the first synchronizer ring 43. Even when the invalid stroke M2R is reduced to zero, the thrust gap M4L between the clutch hub 41 and the second synchronizer ring 44 does not become zero. Therefore, the shift operation can be normally performed. Naturally, although the sleeve 42 is not shown in the neutral state shown in FIG. 8, the shift operation can be normally performed as described above when the shift operation is performed toward the second transmission gear 3 side.

  As described above, in the embodiment to which the feature of the present invention is applied, by restricting the axial displacement amount of the synchronizer rings 43 and 44 with respect to the shifting key 45, the neutral state, that is, the two synchronizer rings 43 and 44 are idle. In a possible state, the inner diameter side cone surfaces 431 and 441 of the synchronizer rings 43 and 44 come into contact with the outer diameter side cone surfaces 211 and 311 of the gear pieces 21 and 31 of the first and second transmission gears 2 and 3. I try to suppress or prevent this. As a result, the inner diameter side cone surfaces 431 and 441 and the outer diameter side cone surfaces 211 and 311 are kept in a separated state, so that friction loss and wear can be reduced. This is advantageous in improving durability.

  In addition, the restriction part (454, 455, 433, 443) is simply provided integrally with the existing shifting key 45 or the synchronizer rings 43, 44, and a new part separate from the existing components as in the conventional example. Therefore, the increase in equipment cost can be suppressed.

  In addition, this invention is not limited only to the said embodiment, It can change suitably in the range equivalent to the claim and the said range.

  In the above embodiment, the type including the lock ball 452 as the shifting key 45 is given as an example, but the present invention is not limited to this. Although not shown in the drawings, the present invention can also be applied to a case where, for example, a band-like shifting key that does not use the lock ball 452 is used. When such a shifting key is used, the arms 454 and 455 as described above may be provided.

1 Rotating shaft
2 First transmission gear 21 Gear piece of first transmission gear 211 Inner diameter side cone surface of gear piece
3 Second transmission gear 31 Gear piece of second transmission gear 311 Inner diameter side cone surface of gear piece
DESCRIPTION OF SYMBOLS 4 Synchronizer 41 Clutch hub 411 Inner diameter side spline of clutch hub 412 Outer diameter side spline of clutch hub 413 Notch of clutch hub 42 Sleeve 421 Inner diameter side spline of sleeve 422 Key groove of sleeve 43 First synchronizer ring 431 First synchronizer ring Cone surface 432 of the first synchronizer ring 433 first recess of the first synchronizer ring 44 second synchronizer ring 441 inner cone surface of the second synchronizer ring 442 outer teeth of the second synchronizer ring 443 second synchronizer ring Second recess 45 Shifting key 451 Shifting key body 452 Shifting key lock ball 453 Shifting key coil spring 454 Shifting key The first arm 455 second arm 456 engaging piece 457 engaging piece of the second arm of the first arm of the shifting key of

Claims (4)

A clutch hub that is externally mounted so as to be able to rotate integrally with the rotating shaft, and an inner diameter side that is fitted to an outer diameter side cone surface of the transmission gear that is externally rotated on one side of the clutch hub on the rotating shaft. Synchronizer ring with cone surface and external teeth, sleeve that is spline-fitted to the outer periphery of the clutch hub, and circumferentially positioned at several locations around the clutch hub and can be displaced in the axial direction And a shifting key having an engaging portion that is detachably engaged with a key groove provided in the axially intermediate portion of the inner diameter side spline of the sleeve,
And a restricting portion for restricting an axial displacement amount of the synchronizer ring with respect to the shifting key,
The restricting portion is provided on the shifting key so as to extend toward the synchronizer ring side, and is provided on the outer periphery of the synchronizer ring so as to be recessed inward in the radial direction so that the distal end side of the arm is engaged. A transmission synchronizer characterized by comprising a recess and a recess. The transmission synchronizer according to claim 1.
A second speed change gear is provided on the other side of the clutch hub, and a second synchronizer ring is also provided on the outer diameter side cone surface of the second speed change gear, and the sleeve slides in one of the axial directions. To receive a shift operation to be
And a second restricting portion for restricting an axial displacement amount of the second synchronizer ring with respect to the shifting key,
The second restricting portion is recessed inward in the radial direction on the outer periphery of the second synchronizer ring, and a second arm provided on the shifting key so as to extend toward the second synchronizer ring. A transmission synchronizer comprising: a second recess which is provided and engaged with a tip end side of the second arm. The transmission synchronizer according to claim 1 or 2,
The shifting key has a body that can accommodate a lock ball and a coil spring, and the coil spring is inserted into the body in a compressed state so that the lock ball is held in the body with an elastic restoring force. It protrudes partially from the upper opening of
When the sleeve is disposed at a neutral position where the sleeve is not meshed with the transmission gear, the lock ball is engaged with the key groove of the inner diameter side spline of the sleeve by the elastic restoring force of the coil spring. The transmission synchronizer is further characterized in that when the sleeve is slid in one axial direction and meshed with the transmission gear, the coil spring is further compressed to escape from the keyway. The transmission synchronizer according to any one of claims 1 to 3,
The arm has elasticity to bend in the radial direction, and a substantially V-shaped locking piece that is bent inward in the radial direction and then outward in the radial direction is provided on the tip side thereof, A synchronizing device for a transmission, wherein the locking piece is engaged with the recess.

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