JPH0799178B2 - Gearbox synchronizer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a transmission synchronizing device used in an automobile or the like.

[Conventional technology]

Conventionally, as a clutch gear of a transmission, for example, Japanese Patent Laid-Open No.
There is one disclosed in Japanese Patent Publication No. 179427. The clutch gear is provided on the main gear, and the outer spline meshes with the spline on the inner side of the coupling sleeve. The clutch gear is provided with a flange integrated with the clutch gear at the main gear side end of the spline. Is. The flange limits the movement of the coupling sleeve at the end of the spline opposite to the coupling sleeve, and by positively forming it in the longitudinal direction to be thick, the overshift of the coupling sleeve is prevented. Prevents and improves the strength of the entire clutch gear.

As another device different from the above, an overshift prevention device for a gear transmission as shown in FIG. 12 is disclosed. The overshift prevention device includes a dog tooth 23 of a clutch gear 24 provided on a gear 22, and a spline 25 capable of meshing with the dog tooth 23 by pressing a synchronizing ring by axial movement on a clutch hub.
A sleeve (21) having a tooth and a protrusion (20) having a tooth profile different from that of the gear (22) at the gear side end of the sleeve (21).
The sleeve 21 is prevented from overshifting by being brought into contact with the end face of 22.

Further, an overshift prevention device for a gear transmission as shown in FIG. 13 is disclosed. The overshift prevention device is
A dog tooth 33 of a clutch gear 34 provided on the gear 32, a sleeve 31 having a spline 35 capable of meshing with the dog tooth 33 by pressing the synchronizing ring by axial movement on the clutch hub, and the gear 32.
It has a stopper plate 30 arranged at the end portion on the sleeve side. The end surface of the sleeve 31 is brought into contact with the stopper plate 30 to prevent the sleeve 31 from overshifting.

As the overshift prevention device as described above, for example,
There is one disclosed in Japanese Utility Model Publication No. 50-53575. An overshift prevention device for a gear transmission has a circumferential groove provided between a clutch spline and its gear portion in a synchronizing device, and divides the ring into two parts, and the divided parts overlap each other and are fitted together. A two-piece snap ring that forms one ring is fitted.

Further, as a gear processing tool, there is one disclosed in Japanese Utility Model Laid-Open No. 62-17019. The machining tool is provided with tooth-shaped blades having different pressure angles on the tooth tip side and the tooth root side with a meshing pitch circle as a boundary.

[Problems to be Solved by the Invention]

By the way, as a device for preventing the overshift of the sleeve as shown in FIG. 10, one having a structure in which a clutch gear of the transmission is provided with a stopper can be considered. The clutch gear has clutch gear dog teeth 29 provided on the gear,
The dog tooth 29 has a stopper 28 integrally projecting from the tooth tip surface 27 of the dog tooth 29 with which the end surface of the sleeve can come into contact. Prevent overshifting of.

However, in the case where the clutch gear of the transmission as described above is provided with a stopper, the tooth profile of the dog tooth provided on the clutch gear is usually an involute tooth profile, but for example, the number of dog teeth 29 is increased. If you let
As shown in FIG. 11, the module becomes smaller and decreases from the tooth thickness A shown by reference numeral (A) to the tooth thickness B shown by reference numeral (B), and in particular, it protrudes from the tooth crest surface 27 of the dog tooth 29. Stopper
The tooth thickness at 28 is extremely reduced from the tooth thickness a to the tooth thickness b. As a result, the tooth thickness of the stopper 28 portion becomes thin, the strength as a stopper is insufficient, and there is a problem that breakage, cracking, or other damage occurs, making it unusable. Therefore, it is necessary to dispose another stopper.

Further, the clutch gear of the transmission disclosed in the above-mentioned Japanese Patent Laid-Open No. 57-179427 is precision forging, and when the stopper by the projection of the dog tooth is not established conventionally, the plate is placed between the clutch gear and the sleeve. The dog tooth and the plate that are sandwiched and used are integrally formed to have a flange portion on the dog tooth, but the tooth profile is not projected from the tooth tip surface of the dog tooth.

Further, the overshift prevention device for a gear transmission disclosed in Japanese Utility Model Laid-Open No. 50-53575 has a snap ring between a gear and a dog tooth, and has a structure in which the gear and the synchro cone are separated. However, there is a problem in that an annular groove for attaching the snap ring to the gear must be formed.

The working tool disclosed in Japanese Utility Model Laid-Open No. 62-117019 is related to a tool for forming a two-step involute tooth profile on a gear, and is a technical idea for preventing overshift of a sleeve of a synchronizer. It's not about.

An object of the present invention is to solve the above-mentioned problems, and to form a protrusion protruding from the tooth tip surface of the dog tooth at the gear side end of the dog tooth of the clutch gear that engages with the spline of the sleeve. Part functions as a stopper for preventing overshifting of the sleeve, and in particular, the tooth profile formed by protruding the stopper at the gear side end of the dog tooth from the tooth tip surface of the dog tooth and forming a pressure angle smaller than the pressure angle of the dog tooth Consisting of
This increases the stopper tooth thickness, thereby increasing the stopper strength and ensuring sufficient strength to prevent overshifting of the sleeve even if the gear module is made smaller and the number of teeth is increased. You can
Moreover, it is an object of the present invention to provide a transmission synchronizing device capable of cutting the stopper like a dog tooth.

[Means for Solving the Problems]

The present invention is configured as follows in order to solve the above problems and achieve the above objects.

That is, the present invention includes a clutch gear having dog teeth provided on the gear, and a spline that is axially movable on the clutch hub and that presses the synchronizing ring to mesh with the dog teeth. In a synchronizer of a transmission having a sleeve, a stopper having a tooth profile protruding from a tooth tip surface of the dog tooth is formed at the gear side end of the dog tooth of the clutch gear, and the tooth profile of the stopper is In order to increase the tooth thickness, the pressure angle of the dog tooth is smaller than that of the dog tooth, and the end surface of the sleeve abuts the stopper to prevent axial overshift of the sleeve. Regarding a synchronizer.

[Action]

Since the transmission synchronizer according to the present invention is configured as described above, it operates as follows. That is, the synchronizer of this transmission has a tooth profile formed at the gear-side end of the dog tooth of the clutch gear, the tooth profile protruding from the tooth tip surface of the dog tooth and having a pressure angle smaller than the pressure angle of the dog tooth. Since the stopper for contacting the end face of the stopper is provided, the tooth thickness of the stopper can be increased as compared with the degree of reduction of the tooth thickness of the dog tooth, and the strength of the stopper can be increased. Therefore, even if the dog tooth, that is, the module of the gear is made small and the number of teeth is increased, the strength of the stopper can be sufficiently secured.

Moreover, since the stopper has a tooth profile formed with a pressure angle smaller than that of the dog tooth, the dog tooth and the stopper can be easily integrated with the dog tooth by creating a gear with a conventional cutting tool such as a pinion cutter. Can be manufactured.

〔Example〕

An embodiment of a transmission synchronizing device according to the present invention will be described below with reference to the drawings.

The transmission synchronizer according to the present invention can be used for the synchronizer of the mechanism shown in FIGS. 1 and 2. In FIG. 1, a spline 11 formed on the inner peripheral side of the sleeve 1
Is spline-fitted to the outer periphery of the clutch hub 2, and is axially moved by a shift fork (not shown) that engages with the recess 1A on the outer peripheral surface of the sleeve 1 and moves in response to a shift operation. can do. Clutch hub 2
Engages with the rotary shaft 7 in a spline manner and rotates integrally with the rotary shaft 7.

Further, the clutch hub 2 is notched in an appropriate number in the circumferential direction, and the key 5 is housed in the notch, and the key 5 is biased radially outward by a spring 6. Key 5
Has a wide convex portion 5A in the central portion, and is fitted in a concave portion 1B formed on the inner surface of the sleeve 1 positioned corresponding to the neutral position of the transmission. On both sides of the clutch hub 2, synchronous rings 3A, 3B, clutch gears 4A, 4B, and gears 9A, 9B integrally formed with the clutch gears 4A, 4B are sequentially arranged. The synchronizing rings 3A, 3B are connected to the clutch gear 4A,
The conical surfaces 10 and 10 can frictionally engage with 4B. Gear 9A, 9B
Is rotatably supported by bearings 8A and 8B with respect to the rotary shaft 7, and always meshes with a gear on another rotary shaft parallel to the rotary shaft 7 (not shown).

In particular, in the above-mentioned configuration, the transmission synchronization device is
As shown in FIG. 3, the dog teeth 12 of the clutch gears 4A, 4B are
It is characterized in that a stopper 13 (a portion S) is provided on the portion (a portion G) and a tooth thickness WA of the stopper 13 is increased. That is, the stopper 13 includes the clutch gears 4A, 4
The dog teeth 12 of B are formed at the ends of the gear teeth 9A and 9B, and the dog teeth 12
Of the tooth tip surface 4C, especially as shown in FIG.
It is formed from a tooth profile formed with a pressure angle β smaller than the pressure angle α of the dog tooth 12.

Therefore, the tooth profile of the stopper 13 is formed in a state in which the curved surface rises from the tooth surface of the tooth tip of the dog tooth 12, and the reduction in the tooth thickness of the stopper 13 is smaller than that of the dog tooth 12, and Even if the size of the module is reduced and the number of teeth is increased, the stopper 13 can be formed to have a tooth thickness that ensures sufficient strength.

However, as shown in Fig. 10, the stopper 28 is
The tooth thickness WB of the stopper 28 becomes extremely small when the tooth profile is formed by directly extending the pressure angle α of 29.

Moreover, if the dog tooth 29, that is, the module of the gear is made small and the number of teeth is increased, the tooth thickness of the dog tooth 29 is the tooth thickness from the gear A shown by reference numeral (A) to the tooth thickness shown by reference numeral (B) in FIG. B, the tooth thickness of the tip surface of the stopper 28 becomes extremely small from the symbol a to the symbol b, and the strength of the stopper 28 cannot be secured.

Therefore, the tooth thickness of the stopper 13 in the synchronizer of this transmission can be increased as compared with the degree of reduction of the tooth thickness of the dog tooth 12, and the strength of the stopper 13 can be sufficiently secured. As a result, the stopper 13 slides toward the gears 9A and 9B side of the sleeve 1 against the end surface 1C of the sleeve 1.
Is brought into contact with the stopper 13 and stopped, and the overshift of the sleeve 1 can be reliably prevented. Moreover, the stopper 13
Since the tooth thickness of itself is large enough to ensure sufficient strength, it is possible to prevent cracks, breakage, etc. of the stopper 13, the dog teeth 12, and the clutch gears 4A, 4B, and to provide a highly durable synchronizing device. Can be provided.

With respect to the operation of the synchronizer of the transmission, when the sleeve 1 is shifted in the left or right axial direction from the shift neutral position shown in FIG. 1 by the shift operation by the shift operation lever, the sleeve 1 moves with the key 5. Sync ring 3A, 3B
While engaging with the gears, the synchronizing rings 3A, 3B are frictionally engaged with the conical surfaces 10, 10 of the clutch gears 4A, 4B,
9A, 9B, that is, the relative rotation with the clutch gears 4A, 4B is reduced, and a synchronous state is established. If you move the sleeve 1 further,
The key 5 is pushed inward in the radial direction against the biasing force of the spring 6, and the teeth on the inner surface of the sleeve 1 are synchronized with the synchronizing rings 3A, 3A.
Engage with B's teeth. When the synchronizing action between the sleeve 1 and the synchronizing rings 3A, 3B is obtained, the sleeve 1 is further moved to smoothly engage with the clutch gears 4A, 4B. Moreover, the end surface 1C of the sleeve 1 is the clutch gears 4A, 4B.
The sleeve 1 comes into contact with a stopper 13 provided at the end of the sleeve 1 to prevent the sleeve 1 from overshifting.

FIG. 2 shows a state in which the sleeve 1 is completely shifted in the axial direction on the right side in the synchronizer of FIG. 1, and the rotary shaft 7 transmits power through the clutch hub 2, the sleeve 1, the clutch gear 4A and the gear 9A. Form a path.

The dog teeth 12 and the stopper 13 in this transmission synchronizer
Can be used for gear cutting using a pinion cutter. That is, the tooth profile of the dog tooth 12 and the tooth profile of the stopper tooth 13 protruding from the tooth crest surface 4C of the dog tooth 12 can be formed simultaneously and integrally by using a pinion cutter.
In this case, by using the pinion cutter PC as shown in FIG. 4 for the cutting edge surface, it is possible to form a two-step tooth profile, that is, the tooth profile of the dog tooth 12 and the stopper 13 as shown in FIG.

The gear cutting principle of the above-mentioned pinion cutter is that a cutter provided with a cutting edge surface is reciprocally moved in the tooth trace direction of a gear and a rotary motion is given to create a virtual gear, and a gear material that makes a rotary motion to this virtual gear. Is applied to the virtual gear and the gear material, and the portion that interferes with the motion of the teeth of the virtual gear is cut from the gear material to create the tooth profile of the gear material.

For example, in FIG. 6, a gear member 43 is cut by a spur type pinion cutter 40 which is a pinion cutter, and the gear member 43 is cut.
An example of creating a spur gear 44 is shown immediately. That is,
The spur type pinion cutter 40 having the incisal tooth surface 41 is reciprocated in the tooth trace direction of the gear to create a virtual gear 42, and the relative movement is given to both so that the gear material 43 meshes with the virtual gear 42 to give the gear material. Immediately after 43, the tooth profile of the spur gear 44 is created.

Further, in FIG. 7, the gear member 48 is gear-cut by a helical pinion cutter 45 which is a pinion cutter.
An example of creating the helical gear 49 is shown in FIG. That is, the helical pinion cutter 45 provided with the cutting edge surface 46 is reciprocally moved in the tooth trace direction of the gear to create a virtual gear 47, and the virtual gear 47 is given a relative motion such that the gear material 48 meshes with both. The helical gear 49 has a tooth profile of the helical gear 49.

Further, in FIG. 8, a gear member 51 is provided by the pinion cutter 50.
The outline of the mechanism of the gear shaper that creates the tooth profile is shown in FIG. When the crank 53 is rotated by driving the motor 52,
The swing arm 55 swings through the crankshaft 54 whose stroke can be changed, and the cutter spindle 56 reciprocates vertically. A guide 59 is provided in the upper master gear 57 at the upper part of the cutter spindle 56.As the guide 59, a straight guide is used when creating a spur gear, and a helical guide is used when creating a helical gear. Using the guide, the cutter spindle 56 is rotated according to the twist angle of the gear to be reciprocated in the vertical direction.

Further, the rotation of the motor 52 is transmitted to the upper master gear 57 through the feed change gear 60 to rotate the cutter spindle 56 and feed the cutter 50 in the rotational direction. The gear member 51 is configured to rotate at a speed ratio corresponding to the cutter 50 by the lower master gear 58 through the feed change gear 60 and the index change gear 61.

FIG. 9 shows a motion state formed with respect to the gear member 51 by the pinion cutter 50 having the above gear shaper mechanism. FIG. 9 is a view seen from the axial direction of the gear member 51, and it can be seen that the tooth profile is formed on the gear member 51.

〔The invention's effect〕

The transmission synchronizing device according to the present invention is configured as described above and has the following unique effects. That is, this transmission synchronizing device includes a clutch gear provided on a gear and provided with dog teeth, and a spline which is axially movable on a clutch hub and presses a synchronizing ring to mesh with the dog teeth. A sleeve provided with, at the gear-side end portion of the dog tooth of the clutch gear, the tooth profile protruding from the tooth tip surface of the dog tooth and formed with a pressure angle smaller than the pressure angle of the dog tooth, Since the stopper for contacting the end faces is provided, the tooth thickness of the stopper formed in the tooth profile can be increased in comparison with the reduction degree of the tooth thickness of the dog tooth, and the tooth thickness of the stopper can be increased. The strength of the stopper itself can be increased.

Therefore, the stopper can sufficiently secure the strength of the stopper without reducing the tooth thickness of the stopper so much even if the dog tooth, that is, the module of the gear is made small and the number of teeth is increased. As a result, the strength of the stopper can be increased, the sleeve can be brought into contact with the stopper to stop the sleeve, and sufficient strength can be secured to prevent overshift of the sleeve.

In addition, since the stopper in the synchronizing device of the transmission is configured to have the tooth profile formed with a pressure angle smaller than the pressure angle of the dog tooth, the dog tooth and the stopper are cut by a conventional pinion cutter or the like. It can be easily manufactured integrally with dog teeth by creating a gear with a tool.

[Brief description of drawings]

1 is a sectional view showing an embodiment of a transmission synchronizing device according to the present invention, FIG. 2 is a sectional view showing a shift position of a sleeve in the synchronizing device of FIG. 1, and FIG. 3 is a line of FIG. III
-III is a sectional view showing a clutch gear, Fig. 4 is a schematic view showing an example of a blade shape of a pinion cutter for creating dog teeth, and Fig. 5 is a dog according to the present invention cut by the pinion cutter of Fig. 4. FIG. 6 is a schematic view showing an example of teeth, FIG. 6 is an explanatory view showing an example of a tooth cutting principle by a pinion cutter, and FIG.
FIG. 8 is an explanatory view showing another example of the principle of gear cutting by a pinion cutter, FIG. 8 is an explanatory view showing an example of the mechanism of a gear shaper,
FIG. 9 is an explanatory view showing a motion state for creating a gear by a pinion cutter, FIG. 10 is a schematic view showing an example of a tooth profile when gear cutting is performed without changing a pressure angle, and FIG. 11 is a module. Fig. 12 is a schematic view showing an example of a tooth profile when gear cutting is performed by changing the gear, Fig. 12 is a schematic view showing an example of a clutch gear of a conventional transmission, and Fig. 13 is an overshift prevention of a conventional transmission. It is the schematic which shows an example of an apparatus. 1 ... Sleeve, 1C ... End surface of sleeve, 2 ... Clutch hub, 3A, 3B ... Synchronous ring, 4A, 4B ... Clutch gear, 4C ... Toe surface of dog tooth, 5 ... Key, 7 ...... Rotary shaft, 9A, 9B …… Gear, 11 …… Spline, 12 …… Dogs, 13 …… Stopper.

Claims (1)

[Claims] 1. A clutch gear having dog teeth provided on a gear, and a spline movably arranged on a clutch hub in an axial direction and pressing a synchronizing ring to mesh with the dog teeth. In a synchronizer of a transmission having a sleeve, a stopper having a tooth profile protruding from a tooth tip surface of the dog tooth is formed at the gear side end of the dog tooth of the clutch gear, and the tooth profile of the stopper is In order to increase the tooth thickness, the pressure angle of the dog tooth is smaller than that of the dog tooth, and the end surface of the sleeve abuts the stopper to prevent axial overshift of the sleeve. Synchronizer.