JPH03172677A - Shift mechanism for transmission - Google Patents

Abstract

PURPOSE:To prevent the engaging claw of an interlock plate from regulating movement of a fork shaft for one step and reverse during EL-ER by producing a difference in a stage between the head part of a shift shaft and the head part, positioned adjacently to the head part of the shift shaft, of one fork shaft and other head parts. CONSTITUTION:A head part 33a of a shift shaft and a head part 30a for first and second step positioned adjacently to the head part of the shift shaft are located in a position moved aside in a direction, extending opposite to a shift select lever 34, from other head parts 31a and 32a to produce a difference D in stage. When the shift select lever 34 is engaged with a head part 33a for EL-ER, an engaging claw 39b of an interlock plate 39 is engaged with only the head part 31a for third - fourth step. Thereby, the head parts 33a, 30a, and 32a are brought into a state to be capable of being shifted, and other head parts 33a, 30a, and 32a than the head part 31a can be integrally shifted through EL-ER shift operation of the select lever 34.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a shift mechanism for a transmission, and particularly to a shift mechanism for a transmission equipped with an auxiliary transmission mechanism having a gear ratio larger than a normally used transmission gear ratio. It is.

[Conventional technology]

2. Description of the Related Art Hitherto, a transmission is known in which, in addition to a main transmission mechanism, a sub-transmission mechanism called an emergency low gear has a gear ratio larger than a first gear. This auxiliary transmission mechanism is used when large driving force is required, such as when a truck loaded with heavy objects starts on a slope, or when a four-wheel drive vehicle escapes from muddy ground.

A general sub-transmission mechanism is provided with a sub-transmission gear having a gear ratio larger than the first gear ratio, and this sub-transmission gear is separated from the main transmission mechanism, as described in Japanese Utility Model Application Publication No. 60-65472, for example. The shift operation is performed using a fork shaft for the auxiliary transmission mechanism.

[Problem to be solved by the invention]

However, in the case of the above-mentioned auxiliary transmission mechanism, the main transmission mechanism and the auxiliary transmission mechanism are selectively operated, so the auxiliary transmission gear can only be used when moving forward, and cannot be used when reversing. . Furthermore, if it is desired to use the auxiliary transmission gear even when reversing, the gear train of the existing transmission with the auxiliary transmission mechanism must be fundamentally changed, which has the drawback of increasing costs.

Therefore, a first object of the present invention is to provide a shift mechanism for a transmission in which an auxiliary transmission gear can be used for both forward movement and reverse movement without changing the gear train of an existing transmission with an auxiliary transmission mechanism. There is a particular thing.

A second object of the present invention is to provide a shift mechanism for a transmission that can prevent shift malfunctions when using an auxiliary transmission gear.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a switching shaft and a fixed shaft of the auxiliary transmission mechanism in parallel with the fork shaft of the main transmission mechanism, and the shift select lever is connected to the head portion of the fork shaft on the switching shaft. A head portion that can be selectively engaged is provided between the switching shaft, the fixed shaft, and the first speed fork shaft of the main transmission mechanism. A first cam plate that integrally moves the fork shaft is installed, and the reverse fork shaft is installed between the switching shaft, the fixed shaft, and the reverse fork shaft of the main transmission mechanism only when the switching shaft moves in the reverse direction. A second cam plate that moves integrally is installed,
The head portion of the switching shaft and the head portion of one fork shaft adjacent thereto are provided with a step relative to the other head portion in the direction facing the shift select lever, and are movable in the axial direction together with the shift select lever. When the shift select lever is engaged with the head of one of the fork shafts, the interlock plate whose rotation is restricted is engaged with the other head, including the head of the switching shaft, and the shift select lever is engaged with the head of one of the fork shafts. When the lever is engaged with the head portion of the switching shaft, it is provided with an engaging pawl that engages with the head portions of other fork shafts other than the first speed fork shaft and the reverse fork shaft. be.

[Effect]

When using a forward gear ratio (referred to as EL) larger than the first gear ratio, the shift select lever is operated to select the EL side. At the same time, the auxiliary transmission mechanism is switched to the low speed ratio side, and then the switching shaft is shifted to the EL side (same direction as the 1st speed direction), and the 1st speed fork shaft also moves together, so the main transmission mechanism Switched to 1st speed. As a result, the first speed of the main transmission mechanism and the low speed ratio of the auxiliary transmission mechanism are established simultaneously, resulting in the EL state.

On the other hand, the reverse gear ratio is larger than the normal reverse gear (this is called ER
(referred to as ER), select the shift select lever to the ER side. At the same time, the auxiliary transmission mechanism is switched to the low speed ratio side, and then the switching shaft is shifted to the ER side (same direction as the reverse direction), and the reverse fork shaft also moves together, so the main transmission mechanism switches to reverse gear. It will be done. As a result, the reverse gear of the main transmission mechanism and the low speed ratio of the auxiliary transmission mechanism are established simultaneously, resulting in an ER state.

In addition, when performing an EL-ER shift, that is, when the shift select lever is engaged with the head of the switching shaft, the interlock plate is connected to the fork shaft other than the first gear fork shaft and the reverse fork shaft. When regulating the movement of the shaft head to obtain a normal gear position, that is, when the shift select lever is engaged with the head of either fork shaft, the interlock plate restricts the movement of the head of the switching shaft. Since the movement of other head parts including the head part is restricted, it is possible to reliably prevent shift malfunctions.

〔Example〕

The drawings show the present invention in 5 forward speeds, 1 reverse speed and EL.

An example is shown in which the present invention is applied to an FR vehicle transmission having an E-R gear stage, in which the fourth speed is a direct gear and the fifth speed is an overdrive. This transmission is generally composed of a main transmission mechanism A and a sub-transmission mechanism B.

The engine output shaft is connected to the input shaft 1 via a clutch (not shown).
is connected to the front end of the The output shaft 2 is arranged coaxially with the input shaft 1, and these axes l.

A sub-shaft 3 is arranged parallel to 2.

A first speed gear 4, a reverse gear 5, and a second speed gear 6 are integrally formed in the center of the input shaft 1. Further, on the input shaft 1, a fifth speed gear 7 is rotatably supported adjacent to the right side of the second speed gear 6, and this fifth speed gear 7 is connected to the input shaft!
A 5-speed switching sleeve 8 is provided which is selectively connected to the 5-speed switching sleeve 8.

A third speed gear 9 is rotatably supported on the right side of the fifth speed switching sleeve 8, and a reduction driven gear 1O is integrally formed at the front end of the output shaft 2 facing the third speed gear 9. has been done. And between the third speed gear 9 and the output shaft 2,
A 3-4 speed switching sleeve 11 is provided to selectively connect the input shaft 1 to the third speed gear 9 or the output shaft 2. A rear end terminal of the input shaft 1 is rotatably supported within the recess of the output shaft 2.

At the front end of the countershaft 3, speed change gears 13.14 that mesh with the first speed gear 4 and the second speed gear 6, respectively, are rotatably supported. A sleeve 15 for selectively connecting the first and second speeds is provided. A reversing gear 16 is integrally provided on this sleeve 15, and this gear 16 can mesh with the reversing gear 5 integrally formed on the input shaft 1 via an idler gear 17 that has been shifted to the position shown by the broken line. be. Further, transmission gears 18 and 19 are integrally formed in the center of the countershaft 3 and mesh with the fifth speed gear 7 and the third speed gear 9, respectively, and furthermore, at the rear of the countershaft 3, the output shaft 2 is connected. Reduction driven gear l
A deceleration drive gear 20 that constantly meshes with O is integrally formed.

The high speed side clutch teeth 22 of the high/low speed switching mechanism 21 are integrally formed in the center of the output shaft 2 of the main transmission mechanism A.
A rear end terminal of the output shaft 2 is rotatably supported within the recess of the output shaft 23 of the sub-transmission mechanism B.

On the output shaft 23 of the sub-transmission mechanism B, there are low-speed side clutch teeth 2.
5a is rotatably supported, and the switching sleeve 26 of the high/low speed switching mechanism 21 is connected to the high speed side clutch teeth 22 or the low speed side clutch teeth 25.
A is connected to the output shaft 23 of the sub-transmission mechanism B. The subshaft 3 of the main transmission mechanism A is extended to a portion corresponding to the high/low speed switching mechanism 21, and a reduction gear 27 that meshes with the reduction gear 25 is integrally fixed onto this extension. The reduction ratio of the reduction gear pair 25°27 is greater than the reduction ratio of the reduction gear pair 10.20 to the main transmission mechanism.The rear end terminal of the output shaft 23 of the sub-transmission mechanism B is It is connected to the rear wheel.

The shift pattern of the above transmission is 1st speed, 2nd speed, and 3rd speed.
Speed and fourth speed, fifth speed and reverse (R), and EL and ER face each other on the same shift operation line, and four head portions 30a to 33a are arranged in parallel accordingly. and,
The shift select lever 34 is one of the above head parts.
is engaged with.

One end of a direction changing lever 35 is close to the EL-ER head part 33a, and the other end of this lever 35 is connected to the rod 3.
6 and the fork 37 to adjust the height of the sub-transmission mechanism B.
It is connected to the low speed switching sleeve 26.

Therefore, when the shift select lever 34 is operated to select the EL-ER side, the direction conversion lever 35 swings counterclockwise, and the high/low speed switching sleeve 26 can be operated to the low speed ratio side. In addition, shift select lever 3
4 to the EL-ER side, the direction conversion lever 35 is biased clockwise or the rod 36 is biased leftward by a biasing means (not shown), so that the high/low speed switching sleeve 26 is Hold high speed ratio position.

FIG. 2 shows a device for preventing malfunction of the shift mechanism.

In the figure, the shift select lever 34 is integrally fixed to the shift select shaft 38.
axial movement is a select operation, and rotation is a shift operation. An interlock plate 39 is inserted into the shift select shaft 38 so as to be relatively rotatable so as to surround both sides of the shift select lever 34, and the interlock plate 39 is rotated by a fixed part such as a transmission case (not shown). It's stopped. Of the four head parts selectively engaged by the shift select lever 34, the adjacent 1st-2nd gear head part 30a and the EL-ER horse head 33a are the 3rd-4th gear head part 31a and the 3rd-4th gear head part 31a. 5th speed-
Shift select lever 34 for R head section 32a
The head portion 30a,
A step is provided between the head portion 33a and the head portions 31a and 32a. Engagement claw 39 of interlock plate 39
a and 39b are opposed to each other with the shift select lever 34 in between, and the engaging claw 39a on the EL-ER head portion 33a side projects more forward than the other engaging claw 39a.

Here, the operation of the malfunction prevention device will be explained with reference to FIGS. 2 to 5.

In the neutral position (3rd and 4th gears), the shift select lever 34 is in the 3rd-4th gear head section 3 as shown in FIG.
1a, and one engaging pawl 39a of the interlock plate 39 is engaged with the 1st-2nd speed head portion 30a and the EL-
The other engaging claw 39b is engaged with the ER horse head 33a and the fifth speed-R head portion 32a, respectively. Therefore,
When the shift select lever 34 is operated, the third
Only the fourth-speed head section 31a is shifted, and the movement of the other head sections is restricted.

When the shift select shaft 38 is operated to select the 5th gear - R direction, the shift select lever 3 is moved as shown in Fig. 3.
4 engages with the fifth speed-R head section 32a, and the remaining three head sections 3 have engaging claws 39a of the interlock plate 39.
0a, 31a, and 33a, when the shift select lever 34 is operated, only the fifth speed-R head section 32a is shifted, and the other head sections are restricted from moving.

When the shift select shaft 38 is operated to select the 1st-2nd speed direction, the shift select lever 3 is moved as shown in FIG.
4 engages with the head section 30a for 1st and 2nd speeds, one engaging claw 39a of the interlock plate 39 is engaged with the EL-ER horse head 33a, and the other engaging claw 39b is engaged with the head section 30a for 3rd and 4th speeds. Since the head portion 31a and the fifth gear-R head portion 32a are respectively engaged, when the shift select lever 34 is operated, only the first and second combination head portions 30a are shifted, and the movement of the other head portions is restricted. be done.

When the shift select shaft 38 is operated to select the EL-ER force direction, the shift select lever 3 is moved as shown in FIG.
4 is engaged with the EL-ER horse head 33a, and the engaging claw 39b of the interlock plate 39 engages only with the 3rd and 4th head portions 31a. Therefore, not only the EL-ER horse head 33a but also the 1st-2nd speed head section 30a and the 5th speed-R head section 32a can be shifted. When the shift select lever 34 is operated in the EL or ER force direction in this state, the EL-ER horse head 33a and the 1st-2nd gear head section 30a or the E
L-ER horse head 33a and 5th speed-R head section 32
a is shifted together. At this time, in order to restrict the movement of the 1st-2nd combination head section 30a in the 2nd speed direction and the movement of the 5th speed-R head section 32a in the 5th speed direction, the steps shown in FIG. Stopper pieces 39c and 39d may be provided on the interlock plate 39 as shown in FIG.

7 and 8 show a one-way movement device of the shift mechanism. Each of the head parts 30a to 32a for the 1st-2nd speed, 3rd-4th speed, and 5th speed-R is the main transmission mechanism. It is formed at the ends of the fork shafts 30 to 32 of A, and these fork shafts 30 to 32 have sleeves 15 for switching between 1st and 2nd speeds and sleeves 11 and 5 for switching between 3rd and 4th speeds shown in FIG. A fork (not shown) for shifting the speed switching sleeve 8 and the idler gear 17 is attached. A switching shaft 33 and a fixed shaft 40 of the sub-transmission mechanism B are provided in parallel with the fork shafts 30 to 32, and the EL-ER head portion 33a is integrally formed at the end of the switching shaft 33. Above fork shaft 30
32 and the switching shaft 33 are supported slidably only in the axial direction by a transmission case or the like, and the fixed shaft 40 is supported immovably in the axial and rotational directions.

A first cam plate 41 is commonly inserted through the switching shaft 33, the fixed shaft 40, and the 12th speed fork shaft 30.
A second cam plate 42 is commonly inserted through the 0 and 5th speed -R fork shafts 32.

A convex portion 33b and a flange 40a for position regulation are respectively provided at the portions of the switching shaft 33 and the fixed shaft 40 sandwiched between the cam plates 41 and 42. Inside each cam plate 41.42, two insertion holes 41a, 41b and 42a, 42b are formed in the planar direction, and these insertion holes have pins 43.44 and 45.46 with spherical ends. is slidably inserted. On the other hand, the portion of the switching shaft 33 that comes into sliding contact with the cam play (41, 42) is provided with the pin 4.
3. Hemispherical groove 330°33d that engages one end of 44
is provided, and the cam plate 41.4 of the fixed shaft 40
2, there are four hemispherical grooves 4 that engage with the other end of the pin 43, 44 and one end of the pin 45, 46.
0b, 40c, 40d, 40e are formed.

Furthermore, a hemispherical concave groove 30b that engages with the other end of the pin 44 is formed in the portion of the first-second speed fork shaft 30 that comes into sliding contact with the first cam plate 41, and A hemispherical groove 32 that engages with the other end of the pin 46 is provided at the portion of the shaft 32 that makes sliding contact with the second cam plate 42.
b is formed.

Here, the operation of the one-sided motion device will be explained with reference to FIG. 9 and FIG. 1O.

First, in order to obtain the EL state, the shift select lever 34 is selectively operated from the neutral state (FIG. 7) to engage the head portion 33a of the switching shaft 33.

As a result, the direction changing lever 35 swings in the first counterclockwise direction, and the high/low speed switching sleeve 26 switches to the low speed ratio side. When the switching shaft 33 is shifted from this state to the EL side as shown in FIG. 9, the first cam plate 41 is pushed by the convex portion 33b and moves together, but the second cam plate 42 Movement is restricted by 40a and held at a neutral position. Therefore,
The pins 43 and 44 inserted into the first cam plate 41 come off the grooves 40b and 40c of the fixed shaft 40 and slide on the fixed shaft 40, and at the same time the pin 44 is inserted into the fork shaft 30 for 1st and 2nd speeds. The first cam plate 4 is deeply engaged with the concave groove 30b, and the fork shaft 30 for the first and second speeds is connected to the first cam plate 4.
Move it together with 1. As a result, the switching shaft 33 and the 1st-2nd speed fork shaft 30 are shifted together toward the 1st speed, and the main transmission mechanism A shifts to the 1st speed.
The sub-transmission mechanisms B are each switched to the low speed ratio side, and the EL
state.

On the other hand, when obtaining the ER state, the shift select lever 34 is engaged with the head portion 33a of the switching shaft 33 from the neutral state (FIG. 7), and the high/low speed switching sleeve 26 is moved to the low speed ratio side in the same manner as described above. Switch to

From this state, turn the switching shaft 33 into the ER position as shown in Figure 1O.
When the shift operation is performed to the side, the second cam plate 42 moves toward the convex portion 3.
Although the first cam plate 41 is pushed by the first cam plate 3b and moves together, the movement of the first cam plate 41 is restricted by the flange 40a of the fixed shaft 40 and is held at a neutral position.

Therefore, the pin 45 inserted into the second cam plate 42
．． The pin 46 is disengaged from the grooves 40d and 40e of the fixed shaft 40 and slides on the fixed shaft 40, and at the same time, the pin 46 is deeply engaged with the groove 32b of the fork shaft 32 for 5th speed -R, and the pin 46 is moved to the 5th speed -R. The R fork shaft 32 is moved integrally with the second cam plate 42. As a result, the switching shaft 33 and the 5th speed-R fork shaft 32 are shifted together in the reverse direction, and the main transmission mechanism A is switched to the reverse gear and the auxiliary transmission mechanism B is switched to the low speed ratio side. , the state becomes ER.

In addition, in order to obtain the normal first speed, when the fork shaft 30 for the first and second speeds is shifted toward the first speed, the pin 44 comes out of the groove 30b, so the first cam plate 41 is moved to the first speed. - It does not operate integrally with the fork shaft 30 for 2nd speed, and only the fork shaft 30 for 12th speed is connected to the first
Can shift towards speed.

Even when obtaining the second speed, the first cam play 1-41 is the 12th
Since it does not work integrally with the speed fork shaft 30, the first
- Only the second speed fork shaft 30 can be shifted independently toward the second speed.

Furthermore, when obtaining a normal reverse gear, if the 5th speed-R fork shaft 32 is shifted in the 1 & reverse direction,
Since the pin 46 is removed from the groove 32b, the second cam plate 42 does not operate integrally with the fifth speed-R fork shaft 32, and only the fifth speed-R fork shaft 32 can be shifted independently in the backward direction. Even when obtaining the 5th speed, the second cam plate 42 does not operate integrally with the 5th speed R fork shaft 32, so the 5th speed-R fork shaft 32
can be independently shifted toward 5th gear.

In the above embodiment, the shift select lever is set to EL-E.
Although we have shown an example in which a rod-type manual shift mechanism is provided in order to switch the sub-transmission mechanism B to the low speed ratio side when the selection operation is made to the R side, the present invention is not limited to this. A power shift mechanism may also be provided.

In addition, in the above embodiment, the EL-ER head section is
Although an example is shown in which it is provided outside the continuous use head section, EL-ER
The head section for the 5th speed-R may be provided outside the head section for the 5th speed-R. In this case, contrary to the above embodiment, the head section for the 1-2 series and the head section for the 3-4 series may be shifted. What is necessary is to make the interlock plate protrude toward the select lever side, retract the 5th speed-R head part and the EL-ER head part, and reverse the interlock plate left and right.

Further, the transmission to which the shift mechanism of the present invention can be applied is not limited to the transmission as in the embodiment having five forward speeds and one reverse speed, but also transmissions other than those described above, such as four forward speeds and one reverse speed. The present invention can also be applied to a transmission having several gear stages. Moreover, it can be applied not only to a two-wheel drive transmission but also to a four-wheel drive transmission.

(Effects of the Invention) As is clear from the above explanation, according to the present invention, a single-motion mechanism is constructed by providing two cam plates, a fixed shaft, and a switching shaft, and a fork shaft for first speed and a fork shaft for reverse movement are provided. The fork shaft is shifted in the opposite direction in conjunction with the switching shaft, making EL-ER possible, so it can be used even when reversing without changing the gear train of the transmission with an auxiliary transmission mechanism that is only used when moving forward. A sub-transmission gear can be used, allowing for diversification of driving.

In addition, by simply providing a step in the head part and changing the shape of the interlock plate, it is possible to prevent double meshing when obtaining normal gears, and also to prevent EL-ER.
Sometimes, the above-mentioned one-way movement mechanism can be realized without restricting the movement of the first continuous use and retraction fork shafts.

[Brief explanation of the drawing]

Fig. 1 is a skeleton diagram of an example of a transmission equipped with a shift mechanism according to the present invention, Fig. 2 is a side view of a shift mechanism malfunction prevention device in a neutral position, and Fig. 3 is a 5th gear - 8 o'clock side view. 4 is a side view of 1st-2nd speed, 5th is a side view of EL-ER, and 6th is VI-Vl of 6th gear.
A line sectional view, FIG. 7 is a side view of the one-way movement device of the shift mechanism,
FIG. 8 is a sectional view taken along the line ■--■ in FIG. 7, FIG. 9 is a side view of the one-sided motion device at EL, and FIG. 10 is a side view of the one-sided motion device at ER. A... Main transmission mechanism, B... Sub-transmission mechanism, 30...
1st-2nd speed fork shaft, 31... 3rd-4th speed fork shaft, 32... 5th speed-R fork shaft, 30a-32a... head part, 33...
Switching shaft, 33a... Head portion, 33b... Convex portion, 34... Shift select lever, 39... Interlock plate, 39a, 39b... Engaging claw, 40
...Fixed shaft, 40a...Flange, 41...
・First cam plate, 42...Second cam plate, 4
3-46...pin.

Claims (1)

[Claims] (1) A main transmission mechanism in which the first forward speed and reverse gear are arranged oppositely on different shift operation lines, and a sub-transmission mechanism having two speed ratios, a high speed ratio and a low speed ratio, and one shift In a transmission that establishes each gear stage of a main transmission mechanism and an auxiliary transmission mechanism by movement of a select lever, a switching shaft and a fixed shaft of the auxiliary transmission mechanism are provided in parallel with a fork shaft of the main transmission mechanism, and the switching shaft is provided with a switching shaft and a fixed shaft of the auxiliary transmission mechanism. The shift select lever is provided with a head portion that can selectively engage with the head portion of the fork shaft;
A first cam plate is provided between the switching shaft, the fixed shaft, and the first speed fork shaft of the main transmission mechanism to integrally move the first speed fork shaft only when the switching shaft moves in the first speed direction. A second cam plate is installed between the switching shaft, the fixed shaft, and the reverse fork shaft of the main transmission mechanism to integrally move the reverse fork shaft only when the switching shaft moves in the reverse direction. The head portion of the switching shaft and the head portion of one fork shaft adjacent thereto are provided with a step in the direction opposite to the shift select lever relative to the other head portions, and are movable in the axial direction together with the shift select lever. When the shift select lever is engaged with the head of one of the fork shafts, the interlock plate, which is rotationally restricted, engages with other head parts including the head of the switching shaft, and When the shift select lever is engaged with the head portion of the switching shaft, an engaging claw is provided that engages with the head portions of other fork shafts other than the first speed fork shaft and the reverse fork shaft. A transmission shift mechanism characterized by: