JP2008215600A - Synchromesh device of manual transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a synchromesh device of a manual transmission reducing the number of part items, superior in installation performance, and superior in meshing performance of a sleeve with a clutch gear. <P>SOLUTION: A ring-shaped synchrospring 8 is arranged in a clearance in the axial direction between a clutch hub 2 and a synchronizer ring 6, and a key part 8b fitted to a hub groove part 2b is arranged in a plurality of places in the peripheral direction in this synchrospring 8. The key part 8b is integrally connected and formed with an engaging part 8b<SB>3</SB>elastically engaging in a neutral position with an inner peripheral groove 7b of the sleeve 7 by projecting to the outer peripheral side, a pressing surface 8b<SB>2</SB>pressed to a cone surface 3b of a shift gear 3 by abutting on a side surface of the synchronizer ring 5 in shift operation of the sleeve, and a sliding contact part 8b<SB>1</SB>frictionally slidingly contacting with a bottom surface of the hub groove part 2b when meshing the sleeve with a clutch gear. Since the sliding contact part 8b<SB>1</SB>frictionally slidingly contacts with the bottom surface of the hub groove part 2b when meshing the sleeve with the clutch gear after finishing synchronization, pressing force to the synchronizer ring 5 is reduced, and the meshing performance is improved. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a synchronous meshing device for a manual transmission.

Conventionally, a synchronous meshing device is known as a shifting clutch mechanism of a manual transmission. There are various types of synchronous meshing devices. Among them, a synchronous meshing device called an inertia lock type (Borgwarner type) is widely used in passenger cars. In the case of an inertia lock type synchronous meshing device, a clutch hub attached to a shaft so as to be integrally rotatable, a transmission gear rotatably supported on the shaft and having a cone surface and a clutch gear, and a cone surface of the transmission gear A synchronizer ring supported on the upper side, a sleeve having an inner spline fitted to an outer spline provided on the clutch hub, and capable of shifting in the axial direction; and a synchronizer key fitted in a toothless portion of the clutch hub; And a key spring for pressing the synchronizer key in the outer circumferential direction. When the sleeve is in the neutral position, the inner circumferential groove of the sleeve and the convex portion of the synchronizer key are fitted to maintain the neutral position, and when the sleeve is shifted from the neutral position to the engagement position, the synchronizer key is The side of the synchronizer ring is pushed against the cone surface of the transmission gear for synchronization.

Such an inertia lock type synchronous meshing device requires a plurality of (for example, three) synchronizer keys and two key springs, has a large number of parts, has a complicated structure, and is disadvantageous in terms of cost. It is. Also, after the synchronization is completed, a strong pressing force from the key to the synchronizer ring is applied, and due to the frictional resistance between the synchronizer ring and the cone surface, the sleeve spline requires a force to push the synchronizer ring away, There was a problem that the meshing performance of the clutch gear deteriorated. The solid line in FIG. 6 shows the change in the pressing force on the synchronizer ring with respect to the movement of the sleeve in the inertia lock type. After the key and the synchronizer ring come into contact, the pressing force becomes the maximum value when the convex portion of the key exceeds the inner circumferential groove of the sleeve. After that, the pressing force decreases, but a considerably large pressing force continues even if the synchronization point is exceeded. This pressing force is influenced not only by the spring force of the key spring but also by the centrifugal force of the synchronizer key, and the meshing performance of the sleeve becomes worse as the rotation speed increases.

In Patent Document 1, hub groove portions are provided at a plurality of locations on the outer periphery of the clutch hub, and key portions of boke springs are assembled to these hub groove portions, and the key portions are connected and formed by a ring portion of a plate material or a wire material. There has been proposed a synchronous meshing device having a structure engaged with the inner circumferential groove. In this synchronous meshing device, since the synchronizer key can be omitted, the number of parts is reduced and the assembly is easy, so that the cost can be reduced. However, since the key part of the boke spring is in contact with the inner peripheral surface of the sleeve even after it is removed from the inner peripheral groove of the sleeve, the key part of the boke spring keeps pushing the side of the synchronizer ring strongly even after synchronization is completed. Therefore, there is a problem that the meshing performance of the sleeve is deteriorated as in the inertia lock type.
Japanese Utility Model Publication No. 3-57523

SUMMARY OF THE INVENTION An object of the present invention is to provide a synchronous gearing device for a manual transmission that has a small number of parts, is excellent in assemblability, and improves the meshing performance of a sleeve with a clutch gear.

To achieve the above object, the present invention provides a clutch hub attached to a shaft so as to be integrally rotatable and having an outer spline on the outer periphery, a transmission gear rotatably supported on the shaft and having a clutch gear and a cone surface. The synchronizer ring supported on the cone surface of the transmission gear and the outer spline of the clutch hub are engaged and shifted in the axial direction to engage the gear portion of the synchronizer ring and the clutch gear of the transmission gear. In a synchronous gearing device for a manual transmission comprising a sleeve having a possible inner spline, hub groove portions are provided at a plurality of locations on the outer periphery of the clutch hub, and an inner peripheral groove is formed on the inner peripheral surface of the central portion of the inner spline of the sleeve. A ring-shaped sync spring is disposed in the axial clearance between the clutch hub and the synchronizer ring, and the synchronizer The lower spring is provided with a plurality of key portions that are elastic in the radial direction and fitted into the hub groove portion in the circumferential direction. The key portion protrudes toward the outer peripheral side and is formed in the inner peripheral groove of the sleeve. An engaging portion that elastically engages at a neutral position; a pressing portion that abuts against a side surface of the synchronizer ring during the shift operation of the sleeve and presses the synchronizer ring against a cone surface of the transmission gear; the sleeve and the clutch gear; A synchronous meshing device for a manual transmission is provided, in which a sliding contact portion that is in frictional sliding contact with the bottom surface of the hub groove portion is integrally formed.

When the sleeve is in the neutral position, the engaging portion of the sync spring is elastically engaged with the inner circumferential groove. When the sleeve is now shifted, the synchro spring engaged with the sleeve moves in the axial direction integrally with the sleeve, and the pressing portion abuts against the side surface of the synchronizer ring on the shift side. Therefore, the synchronizer ring is pressed against the cone surface of the transmission gear, and synchronization is started. When synchronization proceeds and the tip of the inner spline of the sleeve engages with the gear portion of the synchronizer ring, the engaging portion of the synchronizer spring disengages from the inner circumferential groove of the sleeve and rides on the surface of the inner spline of the sleeve. At this time, the sliding contact portion of the sync spring is pressed against the bottom surface of the hub groove portion by the bending reaction force of the key portion of the sync spring. Therefore, after that, the frictional force (pressing force on the synchronizer ring) between the synchronizer spring and the sleeve is reduced by the frictional force between the synchronizer spring and the clutch hub, and the pressing force on the synchronizer ring is reduced. As a result, the frictional resistance between the synchronizer ring and the cone surface is reduced, and the spline of the sleeve can easily disengage the synchronizer ring and easily mesh with the clutch gear, thereby improving the meshing performance of the sleeve. In addition, since the ring part and key part of the synchro spring are integrally provided, it is difficult to be affected by centrifugal force, and the operability of the sleeve does not fluctuate depending on the rotation speed, so that stable performance can be obtained. it can.

The slidable contact portion of the key portion of the synchro spring may already be in contact with the bottom surface of the hub groove portion in the neutral position, or is separated from the bottom surface of the hub groove portion in the neutral position, and only when the hub groove portion is removed from the neutral position. It may be configured to make frictional contact with the bottom surface. That is, the sliding contact portion may be in contact with the bottom surface of the hub groove portion regardless of whether the engaging portion of the sync spring is engaged with the inner peripheral groove of the sleeve, or the engaging portion of the sync spring is While engaged with the inner circumferential groove, the sliding contact portion is separated from the bottom surface of the hub groove portion, and the sliding contact portion is in frictional contact with the bottom surface of the hub groove portion only after the engaging portion is detached from the inner circumferential groove. May be. In the former case, the fitting force between the engaging portion and the inner peripheral groove of the sleeve can be set by the spring elasticity of the key unit alone, so that the fitting force does not vary depending on the rotational speed. In the latter case, there is an advantage that the frictional force between the synchronizer ring and the cone surface at the start of synchronization is not affected by the frictional force between the clutch hub and the synchronization spring. Further, the ring portion and the key portion of the synchro spring may be formed separately, but when they are formed integrally with a plate spring, the synchro spring can be easily manufactured and the cost can be reduced.

As described above, since the synchronizer of the present invention does not require a synchronizer key such as an inertia lock type, the number of parts can be reduced, the size can be reduced, and the cost can be reduced. After the synchronization is completed, if the engaging part of the synchro spring is disengaged from the inner circumferential groove of the sleeve, the sliding contact part of the synchro spring comes into pressure contact with the bottom surface of the hub groove. And the friction force between the clutch hub and the pressing force on the synchronizer ring is reduced. As a result, the frictional resistance between the synchronizer ring and the cone surface is reduced, and the engagement performance of the sleeve is improved.

Embodiments of the present invention will be described below with reference to examples.

1 and 2 show an example of a synchronous meshing device for a manual transmission according to the present invention. A clutch hub 2 is spline fixed to a spline portion 1a provided at an intermediate portion of the shaft 1 so as to be integrally rotatable. At a plurality of locations (for example, three locations at intervals of 120 °) on the outer periphery of the clutch hub 2, hub groove portions 2b are formed by cutting away portions including the outer splines 2a. On the shafts 1 on both sides of the clutch hub 2, transmission gears 3 and 4 having clutch gears 3a and 4a and cone surfaces 3b and 4b are rotatably supported. Synchronizer rings 5 and 6 having gear portions 5a and 6a are supported on the cone surfaces 3b and 4b of the transmission gears 3 and 4, respectively. The synchronizer rings 5 and 6 are engaged with the clutch hub 2 while allowing a predetermined angular displacement.

The inner spline 7a of the sleeve 7 is fitted to the outer spline 2a provided on the outer peripheral portion of the clutch hub 2 so as to be movable in the axial direction. On the inner peripheral surface of the central portion of the inner spline 7a of the sleeve 7, a V-groove inner peripheral groove 7b is formed. The sleeve 7 is shifted in the axial direction by a shift fork (not shown), and the inner spline 7a is engaged with the clutch gears 3a, 4a of the transmission gears 3, 4 via the gear portions 5a, 6a of the synchronizer rings 5, 6. Thus, the clutch hub 2 and any one of the transmission gears 3 and 4 can be selectively connected.

A sync spring 8 as shown in FIG. 3 is arranged in the axial gap between the clutch hub 2 and one of the synchronizer rings 6. The synchro spring 8 generates a frictional force between the synchronizer rings 5 and 6 and the cone surfaces 3b and 4b of the transmission gears 3 and 4 by the spring action when the sleeve 7 is shifted from the neutral position to the engaged position. It is. The synchro spring 8 is formed by bending a single metal plate, and is formed by bending a flat ring portion 8a and a plurality of circumferential portions (here, three at intervals of 120 °) of the ring portion 8a. Part 8b. The ring portion 8 a is disposed in the axial gap between the clutch hub 2 and one synchronizer ring 6, and the key portion 8 b is fitted in the hub groove portion 2 b of the clutch hub 2.

The key portion 8b is formed by bending the inner peripheral side of the ring portion 8a in the axial direction and then turning the tip portion outward so as to have radial spring elasticity. The key portion 8b includes a flat sliding contact portion 8b ₁ extending in the axial direction from the inner peripheral portion of the ring portion 8a along the bottom surface of the hub groove portion 2b, a pressing portion 8b ₂ bent in a U shape, and a pressing portion 8b. It has a structure provided with an engaging portion 8b ₃ which is located at the tip and protrudes to the outer peripheral side. The tip of the engaging portion 8b ₃ is folded inward. The engaging portion 8b ₃ is elastically engaged with the inner peripheral groove 7b of the sleeve 7 in the neutral position. The pressing portion 8b ₂ contacts the side surface of one synchronizer ring 5 and presses the synchronizer ring 5 against the cone surface 3b of the transmission gear 3 when the sleeve 7 is shifted to one side (when shifting to the left in FIG. 1). Works. The sliding contact portion 8b ₁ is in frictional contact with the bottom surface of the hub groove portion 2b when the sleeve 7 and the clutch gear 3a after the synchronization are engaged to generate a frictional force. When the sleeve 7 is shifted to the other side (rightward in FIG. 1), the ring portion 8 a comes into contact with the side surface of the other synchronizer ring 6 to connect the synchronizer ring 6 to the cone of the transmission gear 4. It plays the role of the pressing part pressed against the surface 4b.

In this embodiment, as shown in FIG. 2, the sliding contact portion 8b ₁ of the key portion 8b is not in contact with the bottom surface of the hub groove portion 2b in the neutral position, and a minute clearance exists. Therefore, when the shift operation of the sleeve 7 is started, a frictional force does not act between the key portion 8b and the clutch hub 2, and the shift operation force of the sleeve 7 is transmitted as a force that presses the side surface of the synchronizer ring 5. It is done. In the neutral position, the sliding contact portion 8b ₁ of the key portion 8b may be in contact with the bottom surface of the hub groove portion 2b. In this case, the frictional force between the sliding contact portion 8b ₁ and the hub groove 2b, along with stable position of the sleeve 7 in the neutral position, the key portion 8b of the engaging force between the inner peripheral groove 7b and the engaging portions 8b ₃ It can be set only by the elasticity of the ring, and is not affected by the elasticity of the ring portion 8a.

Here, the operation of the synchronous meshing device having the above configuration will be described with reference to FIGS. In the neutral position, as shown in FIG. 2, the engaging portion 8 b ₃ of the synchro spring 8 is elastically engaged with the inner peripheral groove 7 b of the sleeve 7. When the sleeve 7 is shifted to the left in FIG. 4 for speed change, the sync spring 8 moves in the axial direction integrally with the sleeve 7 by the engagement between the engaging portion 8b ₃ of the sync spring 8 and the inner peripheral groove 7b. Then, the pressing portion 8b ₂ comes into contact with the side surface of the synchronizer ring 5 (see FIG. 4A). Therefore, the synchronizer ring 5 is pressed against the cone surface 3b of the transmission gear 3 to start synchronization.

When the sleeve 7 is further shifted, the synchronizer ring 5 is pressed more strongly against the cone surface 3b of the transmission gear 3 by the synchronization spring 8, and the relative rotational difference between the transmission gear 3 and the synchronizer ring 5 disappears (see FIG. 4B). ). At this time, the engaging portion 8b ₃ is engaged with the inner circumferential groove 7b more or less.

When the synchronization is completed, the tip of internal spline 7a of the sleeve 7 (chamfer) meshes with the gear portion 5a of the synchronizer ring 5, the inner engaging portion 8b ₃ of synchro spring 8 is disengaged from the inner peripheral groove 7b of the sleeve 7 splined It rides on the surface of 7a (see FIG. 4C). As the engaging portion 8b ₃ rides on the surface of the inner spline 7a, the key portion 8 is pushed in the inner diameter direction, so that the sliding contact portion 8b ₁ is pressed against the bottom surface of the hub groove portion 2b by the spring reaction force.

Details of this state are shown in FIG. When the friction force acting between the sleeve 7 and the sync spring 8 is F1, and the friction force acting between the sync spring 8 and the clutch hub 2 is F2, the pressing force F3 from the sync spring 8 to the synchronizer ring 5 is given by Thus, the difference between the two frictional forces F1 and F2 is obtained.
F3 = F1-F2
As described above, since the pressing force F3 against the synchronizer ring 5 is reduced by the friction force F2 acting between the synchronizer spring 8 and the clutch hub 2, the frictional resistance between the synchronizer ring 5 and the cone surface 3b is reduced, and the sleeve 7 can easily engage with the clutch gear 3a by pushing the synchronizer ring 5 away.

FIG. 4D shows a state where the inner spline 7a of the sleeve 7 is engaged with the clutch gear 3a of the transmission gear 3 and the shift operation is finished.

Although the operation when the sleeve 7 is shifted to the left is described in FIG. 4, the same effect can be obtained when the sleeve 7 is shifted to the right. However, in this case, when the sleeve 7 is shifted, the ring portion 8a of the synchronizer spring 8 comes into contact with the side surface of the synchronizer ring 6 and serves as a pressing portion that presses against the cone surface 4b.

FIG. 6 shows the change of the pressing force on the synchronizer ring with respect to the moving amount of the sleeve, the solid line shows the conventional synchronous mesh device, and the broken line shows the synchronous mesh device according to the present invention. In the conventional case, the pressing force after the end of synchronization is large, which causes a reduction in the meshing performance of the sleeve. In the present invention, however, the frictional force F2 acting between the synchro spring 8 and the clutch hub 2 causes the sleeve. Since the frictional force F1 acting between 7 and the synchro spring 8 can be canceled or reduced, the pressing force after completion of synchronization is reduced, and the engagement performance of the sleeve can be improved.

FIG. 7 shows a second embodiment of the present invention. In this embodiment, a key portion 8 c is bent on the outer peripheral side of the ring portion 8 a of the synchronization spring 8. The key portion 8c is formed by bending the outer peripheral side of the ring portion 8a in the axial direction and then turning the tip portion inward, and has radial spring elasticity. Key portion 8b is positioned in the vicinity of the ring portion 8a, an engaging portion 8c ₁ projecting to the outer peripheral side, the pressing portion 8c ₂ that is bent in a U-shape, a flat plate shape extending in the axial direction on the tip side of the pressing portion and a sliding contact portion 8c ₃ of. The engaging portion 8c ₁ engages with the inner peripheral groove 7b of the sleeve 7 in the neutral position, the pressing portion 8c ₂ contacts the side surface of the sync spring 5 and the sliding contact portion 8c ₃ frictionally contacts the bottom surface of the hub groove portion 2b. . In the case of this embodiment, the same effect as that of the first embodiment can be obtained.

Note that, by using the synchronizer spring of the present invention in place of the synchronizer key and key spring in the existing inertia lock type synchronous meshing device, the inertia lock type main parts can be shared as they are. That is, parts such as a clutch hub, a synchronizer ring, and a transmission gear can be used as they are. What is necessary is just to fit the key part of a synchro spring in the hub groove part which the conventional synchronizer key fitted. Therefore, the present invention can be realized at low cost.

The present invention is not limited to the above embodiments. In the above-described embodiment, the clutch gears 3a and 4a are integrally formed with the transmission gears 3 and 4. However, a separate clutch gear may be fixed to the transmission gears 3 and 4 by welding, caulking, or the like. . Further, although the synchronous meshing device in which the transmission gears 3 and 4 are provided on both sides of the clutch hub 2 has been described, the transmission gear may be provided only on one side. In this case, the synchronizer ring may be provided only on one side.

1 is an overall view of a first embodiment of a synchronous meshing device according to the present invention. It is an expanded sectional view of the principal part of FIG. It is a perspective view of the synchro spring concerning this invention. It is sectional drawing which shows the speed change operation | movement of the synchronous meshing apparatus shown in FIG. FIG. 3 is an enlarged cross-sectional view of the synchronous meshing device shown in FIG. It is a figure which shows the change of the pressing force to the synchronizer ring in the synchronous meshing device concerning this invention, and the conventional synchronous meshing device. It is a fragmentary perspective view of the synchro spring of 2nd Example concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shaft 2 Clutch hub 2a Outer spline 2b Hub groove part 3, 4 Shift gear 3a, 4a Clutch gear 3b, 4b Cone surface 5, 6 Synchronizer ring 5a, 6a Gear part 7 Sleeve 7a Inner spline 7b Inner peripheral groove 8 Synchro spring 8a Ring Part 8b key part 8b ₁ sliding contact part 8b ₂ pressing part 8b ₃ engaging part

Claims (1)

A clutch hub that is attached to the shaft so as to rotate integrally and has an outer spline on the outer periphery, a transmission gear that is rotatably supported on the shaft, and that has a clutch gear and a cone surface, and is supported on the cone surface of the transmission gear. A synchronizer ring, and a sleeve having an inner spline that engages with the outer spline of the clutch hub and shifts in the axial direction to engage the gear portion of the synchronizer ring and the clutch gear of the transmission gear. In a manual meshing device of a manual transmission,
Hub groove portions are provided at a plurality of locations on the outer periphery of the clutch hub,
An inner peripheral groove is formed on the inner peripheral surface of the central portion of the inner spline of the sleeve,
A ring-shaped sync spring is arranged in the axial gap between the clutch hub and the synchronizer ring,
The synchro spring is provided with a plurality of key portions in the circumferential direction having spring elasticity in the radial direction and fitted into the hub groove portion,
The key portion has an engaging portion that protrudes toward the outer peripheral side and elastically engages with an inner peripheral groove of the sleeve at a neutral position, and a synchronizer ring that contacts the side surface of the synchronizer ring when the sleeve is shifted. A manual transmission comprising: a pressing portion that presses against a cone surface of a transmission gear; and a sliding contact portion that frictionally contacts the bottom surface of the hub groove when the sleeve and the clutch gear are engaged with each other. Synchronous meshing device.

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