JPH05263834A - Key type synchronizing device for gear transmission - Google Patents

Abstract

PURPOSE:To improve the operativeness of a device by reducing the generation of so called two-stage connection phenomena without complication of the shape of a sleeve, and shortening the axial transfer distance of the sleeve. CONSTITUTION:In a key type synchronizing device for a gear transmission, cam faces 17b, 17c, 21b, 22b are provided to generate an active force to press a shifting key 17 toward outer periphery, on the shifting key 17 and key groove portions 21a, 22a on synchronizer rings 21, 22, by the relative rotation of both members, and the synchronizer rings 21, 22 are constructed with no outer splined portion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key type synchronizer for a gear transmission mainly used in vehicles.

[0002]

2. Description of the Related Art In a key type synchronizer of a gear transmission proposed in Japanese Patent Laid-Open No. 59-23130, an inner spline of a sleeve and an outer spline of a synchronizer ring in a process of axial movement of the sleeve are engaged. There are provided a tooth that performs a synchronizing action in combination with each other, and an auxiliary tooth that extends toward the outer peripheral side of the synchronizer ring and that is formed so as to be positioned close to the gear spline so as to mesh with the gear spline of the gear during the synchronizing action. Thus, the distance from the completion of synchronization to the engagement of the inner spline of the sleeve with the gear spline of the gear is shortened.

[0003]

In the above-described conventional synchronizer, since the distance from the completion of synchronization to the engagement of the inner spline of the sleeve with the gear spline of the gear is shortened, a so-called two-step shift phenomenon, that is, a shift operation is performed. When the gear shift is performed, it is possible to reduce the occurrence of the phenomenon in which the resistance force temporarily disappears and the strong resistance force is felt again after the first resistance is felt by the shift lever until the shift is completed. The shape of the sleeve is complicated because it is necessary to provide teeth to be used and auxiliary teeth. Further, since the teeth of the inner spline of the sleeve and the outer splines of the synchronizer ring are engaged by the axial movement of the sleeve, a synchronizing action is obtained, and it is difficult to shorten the axial movement amount of the sleeve. The present invention has been made to address the above-described problems, and an object thereof is to reduce the occurrence of a so-called two-step insertion phenomenon without complicating the shape of the sleeve, and to shorten the axial movement amount of the sleeve. (EN) Provided is a key type synchronizer for a gear transmission, which is capable of improving operability.

[0004]

In order to achieve the above-mentioned object, according to the present invention, an inner sleeve of a sleeve having an inner spline that selectively meshes with a gear spline of a gear is integrally rotated with a clutch hub. By moving the shifting key axially by the axial movement of the sleeve, which has been fitted to the circumference and has been biased toward the outer circumference by the spring, the shifting key has a key groove on the outer circumference. In a key type synchronizing device of a gear transmission, wherein a synchronizer ring loosely fitted to the taper cone portion of the gear is brought into pressure contact with the taper cone portion for synchronization, in the shifting key and the key groove portion of the synchronizer ring. While providing a cam surface that generates an acting force that presses the shifting key toward the outer periphery by relative rotation of both, The serial synchronizer ring was that there is no configuration of the external spline portion.

[0005]

In the key type synchronizer of the gear transmission according to the present invention, when the sleeve is moved in the axial direction from the neutral position,
The operating force causes the shifting key, which is fitted in the inner circumference of the sleeve, to move in the axial direction, pushes the synchronizer ring in the axial direction, and the synchronizer ring presses against the tapered cone of the gear to cause frictional engagement. To meet. At this time, if there is relative rotation between the gear and the clutch hub, relative rotation occurs between the synchronizer ring that tries to rotate by frictionally engaging the tapered cone of the gear and the shifting key, and the key groove part of the synchronizer ring is generated. And the cam surface provided on the shifting key generates a force to push the shifting key toward the outer circumference. Further, due to the relationship between the sleeve and the shifting key, the operating force for moving the sleeve also generates a force that pushes down the shifting key toward the inner circumference. By deciding the inner peripheral irregularities of the sleeve and the shape of the cam surface so that the force that pushes up the shifting key is larger than the force that pushes it down, the movement of the sleeve is blocked by the shifting key until the synchronization is completed. The sleeve pushes the synchronizer ring against the tapered cone of the gear by the amount of the operating force. When synchronization is completed, the shifting key is pushed inward by the operating force against the spring, the sleeve is allowed to move in the axial direction, and the inner spline meshes with the gear spline of the gear to complete the shift. Become.

[0006]

An embodiment of the present invention will be described below with reference to the drawings. In the gear transmission shown in FIG. 1, the gears 14 and 15 are mounted on the output shaft 11 via bearings 12 and 13 so as to be rotatable and immovable in the axial direction.
A clutch hub 16 is spline-fitted between the gears 14 and 15 so as not to move axially. Clutch hub 16
Has an outer spline (not shown) for supporting the sleeve 19 on its outer circumference, and notches 16a for accommodating the shifting keys 17 at three positions on the outer circumference at equal intervals in the circumferential direction. The shifting key 17 is attached to the notch 16a of the clutch hub 16 so as to be movable in the axial direction and the radial direction, and is biased toward the outer periphery by a pair of ring-shaped springs 18 to be attached to the inner peripheral surface of the sleeve 19. It is pressed, and its convex portion 17a is fitted into the annular concave portion (both sides are tapered) 19a of the sleeve 19 at the neutral position in the figure. The sleeve 19 is constantly meshed with the outer spline of the clutch hub on the inner periphery of the sleeve 19, and each of the gears 14 and 15 to be described later.
Has an inner spline 19b that selectively meshes with the gear splines 14a and 15a, and has an annular groove 19c on the outer periphery into which a shift fork (not shown) is fitted.

The gears 14 and 15 have gear splines 14a and 15a and tapered cone portions 14b and 1 at opposite ends.
5b, and the synchronizer rings 21 and 22 are loosely fitted in the taper cone portions 14b and 15b. Each of the synchronizer rings 21 and 22 has key grooves 21a and 22a for accommodating the respective ends of the shifting key 17 movably in the axial direction and the radial direction at three positions at equal intervals in the circumferential direction on the outer circumference of the opposite ends. In addition, the outer periphery of the shifting key 17 and the key grooves 21a and 22a are not splined relative to each other, as shown in FIGS. 1 and 2. Thus, cam surfaces 17b, 17c and cam surfaces 21b, 22b that generate an action force for pressing the shifting key 17 toward the outer periphery are formed.

In this embodiment constructed as described above, when the sleeve 19 is axially moved to the left from the neutral position in FIG. 1, the shifting force is engaged with the inner circumference of the sleeve 19 by the operating force thereof. The key 17 is moved in the axial direction, and the synchronizer ring 21 abutting against the key 17 is pushed in the axial direction, so that the synchronizer ring 21 is moved to the gear 1
No. 4 taper cone portion 14b is brought into pressure contact with and frictionally engaged. At this time, if there is relative rotation between the gear 14 and the clutch hub 16, relative rotation occurs between the synchronizer ring 21 and the shifting key 17, which are frictionally engaged with the tapered cone portion 14b of the gear 14 and try to rotate, As shown in FIG. 3, the key groove portion of the synchronizer ring 21 and the cam surfaces 21b and 17b provided on the shifting key 17 are in contact with each other. If you try to move the sleeve 19 further to the left,
The sleeve 19 tends to push down the shifting key 17 toward the inner circumference by the action of the annular recess 19a, while the cam surface 21b of the synchronizer ring 21 tends to push up the shifting key 17 toward the outer circumference. These two forces are generated by the force to move the sleeve 19 to the left, and the annular recess 19a and the cam surfaces 21b and 17b are shaped so that the pushing-up force is larger than the pushing-down force. As a result, the synchronizer ring 21 is pushed by the force that moves the sleeve 19 to the left via the shifting key 17 until the relative rotation becomes zero. When the relative rotation becomes zero and the synchronization is completed, the frictional engagement force at the taper cone portion 14b disappears and the force for pushing up the shifting key 17 becomes zero, so that the sleeve 19 resists the shifting key 17 against the spring 18. The inner spline 19b meshes with the gear spline 14a of the gear 14 to complete the shift.

When the sleeve 19 is axially moved to the right from the neutral position in FIG. 1, the gear 15, the shifting key 17, the spring 18, the sleeve 19, the synchronizer ring 22, the cam surfaces 22b, 17c, etc. This provides substantially the same operation as described above.

In the above embodiment, the shifting key 17 is provided with the convex portion 17a and the sleeve 19 is provided with the annular concave portion 19a to carry out the present invention. However, as shown in FIG. It is also possible to implement the present invention by providing the concave portion 117a and the sleeve 119 with the annular convex portion 119a. In this case,
Since the point of action of pushing down the shifting key 117 and the point of action of pushing up the shifting key 117 are close to each other, the rotational moment acting on the shifting key 117 during the synchronizing action can be reduced, and the shifting key 117 is not likely to tilt.

[0011]

As is apparent from the above description, in the present invention, the inner spline of the sleeve may have a single tooth shape as compared with the prior art (apparatus of JP-A-59-23130). The shape of the synchronizer ring is simple because the shape is not complicated and the outer spline of the synchronizer ring is not required. Also, since there is no outer spline on the synchronizer ring, the inner spline of the sleeve and the gear spline of the gear can be placed close to each other at the neutral position, and after the completion of synchronization, the inner spline of the sleeve can be engaged with the gear spline of the gear. The amount of axial movement of the sleeve can be reduced, and the occurrence of the so-called two-step insertion phenomenon can be reduced. Also, due to the relative rotation of the shifting key and the synchronizer ring, the key groove of the synchronizer ring and the cam surface provided on the shifting key generate an action force that pushes the shifting key toward the outer circumference, and the gear and the clutch. A synchronization effect that reduces the relative rotation between the hubs is obtained, and this synchronization effect does not substantially require the axial movement of the sleeve. The shift stroke of the shift lever can be made the same as the conventional one, and the lever ratio can be increased as compared with the conventional one, so that the operating force can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of a key type synchronizer for a gear transmission according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a diagram showing the synchronous operation state of FIG. 2;

FIG. 4 is a vertical sectional side view showing another embodiment of the key type synchronizer for the gear transmission according to the present invention.

[Explanation of symbols]

14, 15 ... Gears, 14a, 15a ... Gear splines,
14b, 15b ... Tapered cone portion, 16 ... Clutch hub, 17 ... Shifting key, 17a ... Convex portion, 17b,
17c ... cam surface, 18 ... spring, 19 ... sleeve,
19a ... annular recess, 19b ... inner splines 21, 22
… Synchronizer rings, 21a, 22a… Keyway,
21b, 22b ... Cam surfaces.

Claims (1)

[Claims] 1. A shifter having an inner spline that selectively meshes with a gear spline of a gear and having a concavo-convex fit on the inner periphery of a sleeve that rotates integrally with a clutch hub and urged toward the outer periphery by a spring. By moving the locking key in the axial direction by moving the sleeve in the axial direction, a synchronizer ring having a key groove in which the shifting key is loosely fitted and which is loosely fitted in the tapered cone portion of the gear is provided in the tapered cone portion. In a key type synchronizer of a gear transmission, which is pressed against and synchronized with a key transmission, an action force for pressing the shifting key toward the outer circumference by relative rotation of the shifting key and the key groove portion of the synchronizer ring. It has a cam surface to generate the above, and the synchronizer ring has no external spline part. Key gear synchronizer for gear transmissions.