JP3155160B2 - Transmission shift mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift mechanism of a transmission for the purpose of reducing weight, reducing the number of parts, and the like.

[0002]

2. Description of the Related Art In a conventional shift mechanism of a constant mesh type (constantly meshing type) transmission having six forward speeds and one reverse speed, for example, as shown in FIG.
A shift rod 51, a shift head 52, a lock ball 53, and a spring 54 are provided for each 0. However, when these are to be accommodated in a cylindrical transmission case, changes such as extending the shift rod are made. And this had resulted in a weight increase.
That is, in the case of a cylindrical transmission case, the core cannot be used depending on the casting method, so that a partition wall for supporting the shift rod cannot be provided at an intermediate position inside the case, and the axial line of the case is not provided. It is designed to support the shift rod at both ends in the direction, so even if there is a shift rod that may be short functionally,
It had to be extended long to accommodate it in a cylindrical transmission case.

To solve such a problem, for example,
A shift mechanism in which a shift fork of a predetermined speed is integrated with a shift rod and a shift head, and the shift fork is mounted on a shift rod of another speed so as to be slidable in the axial direction to reduce the weight. Has been proposed.

[0004]

However, in a shift mechanism provided with a shift member in which a shift fork is integrated with a shift rod and a shift head, the shift fork is operated by a moment force generated in the shift fork when the shift fork is operated. Although there is a certain degree of difference between the member and a shift rod or the like of another shift speed, there is a possibility that twisting (twisting, squeezing, etc.) may occur.

Accordingly, the present invention provides a shift mechanism for a transmission that can be reduced in weight without increasing the weight even when housed in a cylindrical transmission case, and in which twisting or the like is not likely to occur. The purpose is to provide.

[0006]

To achieve the above object, according to the shift mechanism of the transmission of the present invention, a shift fork of a predetermined speed is provided in an equipment case so as to be swingable,
A shift member for operating the shift fork is slidably mounted on a shift rod of another shift stage mounted on the equipment case so as to be slidable in the axial direction of the shift rod. One of them is equipped with a lock ball and a spring for urging the lock ball to the other, and the other is provided with a plurality of ball grooves for engaging the lock ball.

[0007]

According to the present invention, when a predetermined gear is selected, the shift lever is engaged with the shift head, and the shift member of the predetermined gear is slid on the shift rod of another gear, the shift is performed. The shift fork is rotated by the member, whereby the shift operation can be performed.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 to FIG. 5 show an embodiment of the present invention. FIG. 1 is a partially cut-away plan view of a shift mechanism of a transmission according to the present invention, FIG. 2 is a front view of a shift fork, and FIG. 3 is a side view thereof. FIG. 4 is a perspective view of the interlock plate, and FIG. 5 is a sectional view taken along line VV of FIG.

As shown in FIG. 1, this embodiment is, for example, a shift mechanism of a transmission having six forward speeds and one reverse speed , and includes a support hole 1 for vertical walls 11 and 12 in an equipment case 10 of the transmission.
The first and second speed shift rods 20 and the third
A fourth-speed shift rod 21 is provided parallel to each other and movable in the axial direction.

A first / second speed shift fork 22 and a first / second speed shift head 23 are fixed to the first / second speed shift rod 20 at a distance from each other in the axial direction via fixing means such as bolts and pins. Equipped with 3rd and 4th speed shift rod 2
The 1 is fixedly equipped with a 3/4 speed shift fork 25 via a 3/4 speed shift head 24. At the upper ends of the first and second speed shift heads 23 and the third and fourth speed shift heads 24,
Engagement grooves 23a with which the inner lever 30 engages,
24a are formed.

On the first and second speed shift rods 20, a swing type reversing shift fork 26, which is swingably mounted on the equipment case 10 via pins 26a (see FIGS. 2 and 3), is operated. The shift member 27 is supported so as to be slidable in the axial direction of the shift rod 20.
The reverse shift member 27 includes a substantially cylindrical support portion 27a.
An arm portion 27b extending from the support portion 27a in parallel with the first and second speed shift rods 20; and an engagement groove 27c provided at the distal end of the arm portion 27b and engaging the inner lever 30 at the upper end. And the reverse shift head 27d. The support portion 27a is located on the reversing shift fork 26, is provided with an engaging recess 27e on one side to which the head 26b of the reversing shift fork 26 engages, and locks on the other side. An accommodation portion 27f for accommodating the ball 31 and a coil spring 32 for urging the lock ball 31 to one side surface of the first / second speed shift rod 20 is provided. On one side surface of the first / second speed shift rod 20, three ball grooves 20a with which the lock ball 31 is detachably engaged are provided. These lock ball 31, coil spring 32, ball groove 20
“a” gives a sense of moderation during shift positioning and shift operation.

Similarly, the third and fourth speed shift rods 21
On the top, a swing-type fifth device, which is swingably mounted on the device case 10 via a pin 28a (see FIGS. 2 and 3).
5th and 6th for operating the 6th speed shift fork 28
A speed shift member 29 is slidably supported in the axial direction of the shift rod 21. This 5.6 speed shift member 2
9 also includes a substantially cylindrical support portion 29a and an arm portion 2 extending from the support portion 29a in parallel with the third and fourth speed shift rods 21.
9b and a 5.6 speed shift head 29d provided at the tip of the arm portion 29b and having an engagement groove 29c at the upper end for engaging the inner lever 30.
The support portion 29a is located on the fifth / sixth speed shift fork 28, and an engagement recess 29e with which the head 28b of the fifth / sixth speed shift fork 28 engages is provided on one side. In addition, a housing portion 29f for housing a lock ball 33 and a coil spring 34 for urging the lock ball 33 to one side surface of the third / fourth speed shift rod 21 is provided on the other side. . Third and fourth speed shift rod 21
On one side surface, there are provided three ball grooves 21a with which the lock ball 33 is detachably engaged. These lock ball 33, coil spring 34, ball groove 21a
This also provides a sense of moderation during shift positioning and shift operation.

The shift mechanism of the transmission described above has an approximately octagonal shift rod 2 to prevent double meshing.
An interlock plate 35 is disposed so as to be movable in a direction (selection direction) perpendicular to an axis such as 0. At the center of the lower surface of the interlock plate 35, as shown in FIGS. 4 and 5, projections 35a, 35a extending in a direction perpendicular to the axis of the shift rod 20 and the like are provided.
5a and 35a are shift heads 23, 24, 29d and 2
7d engages with the engagement grooves 23a, 24a, 27c, 29c (see FIG. 1). In the middle of the interlock plate 35 between the ridges 35a, 35a,
A shift groove 35b extending in a direction orthogonal to 5a, 35a is provided, and for moving any one of the shift rods 20, 21, and the shift members 27, 29 in the axial direction through the shift groove 35b. The inner lever (shift lever) 30 has its shift heads 23, 24, 27
d, 29d to be engaged with any one of the engagement grooves 23a, 24a, 27c, 29c.

As shown in FIG. 1, each shift rod 20,
21 and the shift members 27 and 29, when in their neutral positions, respectively, engage the grooves 23a, 24a, 27c and 29c of the shift heads 23, 24, 29d and 27d.
Are arranged in a line in a direction perpendicular to the axis of the shift rod 20 and the like, and engage with the ridges 35a except for those located in the shift grooves 35b, whereby the movement in the axial direction is restricted by the ridges 35a. It is in the state where it was. Engagement grooves 23a, 24a, 2
The shift rods 20 and 21 and the shift members 27 and 29c in which the shift rods 7c and 29c are located in the shift groove 35b are released from the restraint of the ridge 35a.
An operation in the axial direction (shift movement) is permitted by 0.

Next, a gear shift operation by the shift mechanism of the transmission according to this embodiment will be described.

First, the inner lock plate 35 is moved by a select lever (not shown) to
b is moved onto the shift head (engagement groove) of the desired speed, and the inner lever 30 is moved to the engagement groove of the shift head of the desired speed, for example, as shown in FIG. The head 23 is engaged in the engagement groove 23a. When the inner lever 30 is rotated in this state until it comes into contact with the front end or the rear end (stopper) of the shift groove 35b, the first- and second-speed shift rods 20 and the shift fork 22 move in the axial direction together with the shift head 23. Inner lever 3
The rotation of 0 is restricted by the front end or the rear end (stopper) of the shift groove 35b. After the shift operation, the shift rod 20 is maintained at the shift position by the engagement between the lock ball 31 and the ball groove 20a. At this time, through the engagement between the lock ball 31 and the ball groove 20a, a force for moving the shift rod 20 in the axial direction from the shift rod 20 acts on the shift member 27. Blocked by engagement. As a result, a sleeve (not shown) fitted to the tip of the shift fork 22 moves, and the hub spline-coupled to the output shaft meshes with the first-speed or second-speed driven gear.

When shifting to the fifth or sixth speed,
The inner lock plate 35 is moved by the select lever so that the shift groove 35b is located on the engagement groove 29c of the 5.6th-speed shift head 29d. Then, the inner lever 30 is moved to the engagement groove 29c of the shift head 29d.
, And rotated until it comes into contact with the front end or the rear end (stopper) of the shift groove 35b.
At the same time, the support portion 29a moves in the axial direction,
9a causes the 5.6 speed shift fork 28 to
It turns to either one of the fifth speed or the sixth speed with a being a fulcrum. As a result, a sleeve (not shown) fitted to the tip of the shift fork 28 moves, and the hub spline-coupled to the output shaft meshes with the fifth or sixth speed driven gear.

Similarly, when shifting to the reverse speed, the inner lock plate 35 is moved by the select lever so that the shift groove 35b is positioned above the engagement groove 27c of the shift head 27d at the reverse speed. Then, the inner lever 30 is engaged with the engagement groove 27c of the shift head 27d.
, The support portion 27a moves in the axial direction together with the shift head 27d, and the shift fork 26 rotates around a pin (not shown) as a fulcrum by the support portion 27a. As a result, the sleeve (not shown) fitted to the tip of the shift fork 26 moves, and the hub spline-coupled to the output shaft meshes with the reverse driven gear.

According to the above-described embodiment, the first and second speed shift rods 20 support the reverse shift member 27, and the third and fourth speed shift rods 20 support the fifth and sixth speed shift rods. The member 29 is supported, and the first
Since the lock balls 31, 33 and the like are arranged between the second speed and the reverse speed and between the third and fourth speeds and the fifth and sixth speeds, the shift rod, the shift ball and the like are provided for each shift fork. As compared with the conventional shift mechanism shown in FIG.
The number of parts can be greatly reduced and the weight can be reduced. Even when the transmission case is housed in a cylindrical transmission case, the transmission member is extended by extending the shift member 27 of the reverse gear and the shift member 29 of the fifth and sixth speeds. It is not necessary to support at both ends in the axial direction, and the problem of weight increase does not occur.

Further, since the shift forks 28 and 26 of the fifth and sixth speeds and the reverse gear are of a swing type, there is no need to provide an inversion lever, and the engagement recesses 29e,
27e and the heads 28b, 26 of the shift forks 28, 26
There is no possibility that a moment will be generated during the shift operation due to the slip between them.

Further, the positioning of the shift rods 20, 21 and the shift members 27, 29 is performed by the interlock plate 3.
5 and adopting a cylindrical transmission case, there is no problem that the position of the lock balls 31, 33 and the position of the interlock plate 35 are shifted.

In the above embodiment, the first and second speed and third and fourth speed shift rods 20 and 21 support the reverse gear and the fifth and sixth speed shift members 27 and 29 in a slidable manner. However, the present invention is not limited to this. Also, the lock balls 31, 33,
Although the case where the springs 32 and 34 are supported is shown, the shift rods 20 and 2 for the first and second speeds and the third and fourth speeds are shown.
1 may be provided with a support portion to support the lock ball 31 and the like. Also, the case where the protruding ridges 35a, 35a are provided on the interlock plate 35 is shown, but instead of the protruding ridges 35a, 35a, for example, grooves into which upper ends of shift heads 23, 24, 27d, 29d are fitted And the shift groove 35b may be provided so as to be orthogonal to the groove.

[0024]

As described above, according to the present invention, the equipment case is provided with a shift fork of a predetermined speed so as to be swingable, and the shift fork of another speed provided in the equipment case is mounted on the shift rod. A shift member for operating the shift fork is provided so as to be slidable in the axial direction of the shift rod, and a lock ball and the lock ball are attached to one of the shift member and the shift rod. equipped with a spring for energizing the other to, a plurality of ball grooves of the lock balls are engaged and said shift fork
And forming an engagement recess in one of the shift members,
On the other hand, a head that slidably engages with the engaging recess is formed, so that the number of parts is significantly reduced for each shift fork as compared with a shift mechanism equipped with a shift rod, a shift head, a lock ball, and the like. Therefore, there is no risk of weight increase even when housed in a cylindrical transmission case, and it is possible to reduce the weight, and there is no risk of twisting or the like occurring during a shift operation . In addition, rock ball, spring and
And ball groove, both shift rod and shift member
Gives a sense of moderation during shift positioning and shift operation.
Can be.

[Brief description of the drawings]

FIG. 1 is a plan view of a shift mechanism of a transmission according to the present invention, in which a part of a shift mechanism is omitted and partially cut away.

FIG. 2 is a front view of a shift fork operated by a shift member.

FIG. 3 is a side view of the same.

FIG. 4 is a perspective view of an interlock plate.

FIG. 5 is a sectional view taken along the line VV of FIG. 4;

FIG. 6 is a perspective view of a conventional shift mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Device case 20, 21 Shift rod 27, 29 Shift member 26, 28 Shift fork 30 Inner lever 31, 33 Lock ball 32, 34 Spring 35 Interlock plate 35a Ridge 35b Shift groove

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-277866 (JP, A) JP-A-5-118439 (JP, A) JP-A-51-113576 (JP, U) (58) Survey Field (Int.Cl. ⁷ , DB name) F16H 63/00-63/38

Claims (4)

(57) [Claims] 1. A shift member for operating a shift fork, which is provided on a shift case of another shift speed mounted on the equipment case, wherein a shift fork of a predetermined shift speed is swingably mounted on an equipment case. The shift rod is provided so as to be slidable in the axial direction, and one of the shift member and the shift rod is provided with a lock ball and a spring for urging the lock ball to the other, and the other is provided with the lock ball. There is provided a plurality of ball grooves for engaging and said shift
An engagement recess is provided on either the fork or the shift member.
Formed on the other side, a head slidably engaged with the engagement recess.
Shift mechanism of a transmission, characterized by comprising forming. 2. The shift mechanism for a transmission according to claim 1, wherein the shift fork includes a reverse shift fork and a fifth shift fork.
The shift member for operating a six-speed shift fork is a reverse-stage shift member and a fifth- or sixth-speed shift member, and the reverse-stage shift member and the fifth- or sixth-speed shift member are operated. Wherein the shift rod is slidably mounted in first and second speeds and third and fourth speeds. 3. The shift mechanism of a transmission according to claim 1, wherein two or more shift rods and a shift member are engaged with the shift rod and the shift head of the shift member in the equipment case. The transmission is characterized in that it is equipped with an interlock plate, which simultaneously restrains the shift rod and the shift member so as not to move in the axial direction, so that the interlock plate can be moved in a direction orthogonal to the axial direction of the shift rod and the shift member. Shift mechanism. 4. The shift mechanism of a transmission according to claim 3, wherein the interlock plate is orthogonal to the shift groove along a shift groove along a moving direction of the shift rod and the shift member, and A shift mechanism for a transmission, comprising: a shift rod; and a projection that engages with an engagement groove provided in a shift head of the shift member and restricts movement thereof.