JPS59164442A - Shift device in multistep transmission for vehicle - Google Patents

Abstract

PURPOSE:To shorten the length of a transmission shaft direction, by making a shift fork for forward maximum speed step use movable together with a movable fork shaft in time of maximum speed step shifting, and also making the movable fork shaft alone movable in time of backward speed step shifting. CONSTITUTION:A movable fork shaft 2 is secured tight with a control member 11 of a backward transmission step control mechanism R, while the end part of an arm body 11a extending solidly from the member 11 is formed in U-shaped form, engaged slidably with a fixed fork shaft 3 and serves as a rotation stabilizer for the movable fork shaft 2. A fork claw 14a on the tip of a backward shift fork 14 embraces a backward idle gear 16, and when the movable fork shaft 2 gets sliding, the backward fork member 14 rocks, shifting the backward idle gear 16, thus a transmission T can be connected to a backward transmission step. Therefore, when the first fork shaft 2 is slidden toward the right from a neutral position, a speed shaft fork 4 is shifted whereby the transmission shifts into the fifth speed step, and when the movable fork shaft 2 is slidden toward the left from the neutral position, the backward shift fork 14 shifts so that the transmission is shifted into a backward speed step.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a shift device in a manually operated multi-stage transmission for a vehicle.

Reducing the weight and size of automobiles is one of the technical means to improve the performance of automobiles.

Generally speaking, in automobiles, reducing the weight and size of the power unit greatly contributes to reducing the weight and size of the entire vehicle, and technological development has been carried out for this purpose.

Therefore, the present invention aims to reduce the size and weight of the multi-stage transmission that constitutes the power unit.In the manually operated multi-stage transmission, the length in the gear shift axis direction is shortened, thereby making it more compact. In order to achieve the purpose of reducing the weight and weight of the movable fork shaft, a movable fork shaft is supported in the transmission case so as to be slidable in the axial direction, and a fixed fork shaft is fixedly supported in parallel with the movable fork shaft. A seven-foot fork for the highest forward speed is slidably provided on the fork shaft, and a shift fork for the reverse gear is connected to the fork shaft, and a shift fork for the highest forward speed is connected between the movable fork shaft and the fixed fork shaft. The shift fork for the highest gear is locked together so that it can move together with the movable fork shaft, and the shift fork for the highest gear is left in the neutral position when shifting to the reverse gear.
A shift fork operation regulating device is provided that releases the lock so that only the movable seven-nork shaft can be moved to the reverse gear position.

By the way, in general, manually operated multi-speed transmissions are shown in Figure 1 (,
4) Gear shift patterns such as those shown in (5-speed gear shift) and Figure 1 (B) (7-speed gear shift) have been adopted, and these shift patterns in which the highest gear and reverse gear are on the same shift line. The conventional shift device for such a transmission has a shift fork for the highest speed fixed to a shift shaft that is slidably supported in the axial direction in the transmission case, and When the shaft is controlled to slide in one direction, the shift fork is shifted to the highest speed position, and when the shift shaft is controlled to slide in the other direction, the reverse shift member provided on the shaft is shifted to the reverse gear position. It is now being shifted to

By the way, a shift fork generally has an axially long boss part on the shift shaft in order to prevent it from collapsing during sliding and to achieve smooth gear changes. In order to secure this space, the transmission case had to become longer in the axial direction of the shift shaft.

According to the present invention, as will be clear from the embodiments described below, when shifting to the reverse gear, the shift fork member for the highest speed gear stays at the neutral position and further movement is inhibited. By eliminating the movement of the fork toward the mission case wall, the mission case can be made smaller and lighter.

Embodiments in which the present invention is applied to a five-speed transmission will be described below with reference to FIGS. 2 to 5.

In FIG. 2, a movable fork shaft 2 is supported in a mission case 1 so as to be slidable in the axial direction, and a fixed fork shaft 3 is secured parallel to the movable fork shaft 2 by a locking pin 1°. Supported. A shift fork 4 for the highest speed, that is, a 5th speed, is supported on the movable fork shaft 2 so as to be slidable in its axial direction.
is engaged with the fifth speed sleeve 50 circumferential groove 5cL. Said 5
The speed sleeve 5 connects the transmission T to the 5th gear by integrally coupling the 5th speed gear 7 rotatably supported by the speed change shaft 6 with the speed change shaft 6 as usual, or connects the transmission T to the 5th speed. That is, the fifth-speed sleeve 5 is slidably engaged with the outer periphery of a synchronizer hub 8 that is spline-engaged on the shift shaft 6. When the 5-speed shift fork 4 is moved to the right from the neutral position shown by the solid line in FIG. The transmission gear 7 is engaged with the transmission gear 7 so that the rotation of the transmission gear 7 can be transmitted to the transmission shaft 6.

An operating member 11 of a reverse gear operating mechanism R is fixed to the movable fork shaft 2, and an arm body 11. The end portion of z is formed into a U shape and is slidably engaged with the fixed fork shaft 3, thereby serving to prevent the movable fork shaft 20 from rotating. Said operating member 1
An engagement pin 12 is integrally protruded from the boss portion of the transmission case 1, and this engagement pin 12 is connected to the base of the reverse shift fork 14, which is swingably connected to the support wall 1a integral with the transmission case 1 by a pin 13. It is engaged with a hook-shaped through hole 15 formed at the end. Fork pawl 14 at the tip of shift fork 14 for reverse movement
α holds the reverse idle gear 16, and when the movable fork shaft 2 slides to the right in FIG. 3 (second fixed position),
The reverse fork member 14 can swing to shift the reverse idle gear 16 and connect the transmission T to the reverse gear. Therefore, if the first forkshaft 2 is slid to the right from the neutral position in FIG.
The continuous shift fork 4 is shifted and the transmission is shifted to the fifth speed, and if the movable fork shaft 2 is slid to the left from the neutral position in FIG. 1, the reverse shift fork 14 is shifted as described above. The transmission is shifted to reverse speed.

In FIG. 1, 17 is a shift fork for the first and second speeds that is slidably provided on the fixed fork shaft 3, 18 is a sleeve for the first and second speeds, and 19 is a shift fork that is slidable on the movable fork shaft 2. Shift fork for 3rd and 4th speed installed in
20 is a sleeve for third and fourth speeds; 21 is a conventionally known select and shift mechanism S for connecting the shift forks 17 and 1;
9. This is a gear lever that selectively operates 4 and 14.

Incidentally, a shift fork operation regulating device C for regulating the movement of the fifth speed shift fork 4 is provided between the movable and fixed fork shafts 2.3. This device C is comprised of a locking mechanism and a stopper ring 29, which will be described below. Next, the structure of the locking mechanism will be described. The boss portion 4h of the shift fork 4 is provided with a locking hole 22 whose both ends are open facing the movable and fixed fork shafts 2 and 3. In this locking hole 22, there is a first locking hole.
A 20th lock ball 23, 24 is movably housed, and a compression spring 2 is placed between the 20th lock balls 23, 24.
5 is contracted and a pin 26 is housed therein. The springing force of the compression spring 250 acts to spring the locking balls 23, 24 towards the movable and fixed fork shafts 2, 3, respectively, and the pin 26 acts to spring the locking balls 23, 24 towards the movable and stationary fork shafts 2, 3, respectively, and the pin 26 is caused to spring against the first and second fork shafts 2,3.
This restricts the retreat of the 20th tank ball 23.24.

The movable fork shaft 2 includes the shaft 2 and a fifth
When the speed shift fork 4 is in the neutral position, the first
A notch 27 is formed that engages with the 0-turn ball 23, and the fixed fork shaft 3 has notches 2B, 28' that engage with the 20th push ball 24 when the shift fork 4 is in the neutral position and the 5th gear position. It is formed.

Further, the stopper ring 29 is connected to the movable fork shaft 2.
It is fixed to the top and engaged with the stepped portion of the shift fork 4 to restrict movement of the shift fork 4 to the left.

Next, the operation of the first embodiment of the present invention will be explained.

In FIG. 5, (a) shows the state when the vehicle is in neutral, (b) shows the state when shifting to fifth gear, and ()→ shows the state when shifting to reverse.

Now, in order to shift from the neutral position shown in Figure 5 (a) to 5th gear,
When the movable fork shaft 2 is moved to the right, the 5th speed shift fork 4 is also shifted in the same direction via the stopper ring 29, and the 5th speed sleeve 5 that is engaged therewith is shifted to the 5th speed position, as described above. The transmission T is shifted to the fifth speed as shown in FIG. In this case, the 20th locking ball 24 of the locking mechanism is engaged with the notch 28' of the fixed fork shaft 3.

Next, when the movable fork shaft 2 is moved to the left from the neutral position shown in FIG. While the shift fork 4 is stopped at the neutral position, only the movable fork shaft 2 slides further to the left, moving the reverse operation member 11 fixed thereto in the same direction and engaging the reverse operation member 11. The fork member 14 is swung to connect the transmission T to the reverse position as described above.

FIG. 6 shows a second embodiment of the device of the present invention.

This second embodiment differs from the first embodiment in the structure of the locking mechanism. In other words, 5-speed shift fork 4
The locking hole 221 drilled in the boss portion 4ψ of the first one has a spherical engaging portion at its tip. 20th piece piece 30,3
1 is slidably provided, and those tapy 230.31
A compression spring 25° is interposed between the springs 25. The elastic force of is the movable fork shaft 2 and fixed fork shaft 3.
It is configured to engage notches 27, 28 formed in the. Then, the back surfaces of the pair of lock pieces 30 and 31 abut against each other, and their retreated positions are regulated.

FIG. 7 shows a third embodiment of the device of the present invention.

This third embodiment also differs from the first embodiment in the structure of the locking mechanism. That is, the boss portion 4 of the shift fork 4
A lock piece 32 having spherical engaging portions at both upper and lower ends is slidably housed in the lock hole 222 drilled in b, and is compressed between the lock piece 32 and the end wall of the lock hole 222. A spring 25□ is interposed, and the elastic force of this spring 252 biases the lock piece 32 toward the fixed fork shaft 3 side.

Furthermore, FIG. 8 shows a fourth embodiment of the device of the present invention. This fourth embodiment also has the structure of the locking mechanism similar to that of the first embodiment.
This is different from the example. That is, one lock ball 33 is accommodated in a shallow locking hole 253 drilled in the fifth-speed shift fork 4, and a portion of this locking ball 33 protrudes from the locking hole 253 and directly connects to the upper surface of the fixed fork shaft 3. When the movable fork shaft 2 and the fifth-speed shift fork 4 are both in the neutral position, the locking ball 33 can engage with the notches 27, 28 of the movable and fixed fork shafts 2, 3. Note that this embodiment does not require the fifth speed notch 28'.

All of the locking mechanisms shown in the second to third embodiments have the same functions as those shown in the first embodiment.

As described above, according to the present invention, a movable fork shaft is supported slidably in the axial direction in the mission case, and a fixed fork shaft is fixedly supported in parallel with the movable fork shaft, and the movable fork shaft is provided for the highest forward speed. With a slidable shift fork! (The operating member for reverse gear is fixed, and the shift fork is integrally locked between the movable fork shaft and the fixed fork shaft so that the shift fork can move together with the movable fork shaft when shifting to the highest gear. Since a shift fork operation regulating device is provided that releases the locking during gear shifting, when switching to reverse gear, the shift fork (generally, the boss portion thereof is formed long in the axial direction to prevent it from collapsing during shifting) is provided. ) is not shifted, so there is no need to provide a shift space in the transmission case for the shift fork to shift in the reverse gear switching direction, and the length of the transmission case in the shift direction can be shortened accordingly. This allows the mission case to be made smaller and lighter.

[Brief explanation of the drawing]

Figures 1 to 5 show the first embodiment of the device of the present invention.
The figure is a longitudinal sectional side view of a part of the mission equipped with the device of the present invention, FIG. 3 is a sectional view taken along the line m-ITI in FIG. 2, FIG. Figures (A), (B) and C→ are sectional views showing the effects of the present invention, FIG. 6 is a partial sectional view showing the second embodiment of the device of the present invention, and FIG. FIG. 8 is a partial sectional view showing a fourth embodiment of the apparatus of the present invention. C...Shift fork operation regulating device, 2...Movable fork shaft, 3...Fixed fork shaft, 4...
・Shift fork for 5th speed, 14...Shift fork for reverse gear 1st gear A No. 6 Fig. 5

Claims (1)

[Claims] In a vehicle multi-speed transmission equipped with a shift pattern in which the highest speed of a forward multi-speed shift and a reverse gear can be selected by a shift operation on the same shift line, a mission case (1
) supports the movable fork shirt r(2) so as to be able to slide in the axial direction, and a fixed fork shaft (
3), the movable fork shaft (2) is slidably provided with a shift fork (4) for the highest forward speed, and a shift fork (14) for the reverse gear is connected to the movable fork shaft (2). (2) and the fixed fork shaft (3), the shift fork (4) for the highest forward speed is connected to the movable fork shaft (2) when shifting to the highest speed.
) and lock them together so that they can move together with the highest gear shift lever (4) when shifting to reverse gear.
while leaving the movable fork shaft (2) in the neutral position.
1. A shift device for a multi-speed transmission for a vehicle, characterized in that a shift fork operation regulating device (C) is provided, the shift fork operation regulating device (C) being configured to release the lock so that only the shift fork (C) can be moved to a reverse gear position.