JPS61266855A - Shift operation mechanism for speed change gear - Google Patents

Abstract

PURPOSE:To simplify the structure by making a shift stroke slip by the amount of shift in which a small amount of shift is subtracted from the shift amount of a shift actuator in a shift shaft having a small amount of shift so that the difference in the shift can be absorbed. CONSTITUTION:Shift shafts 2 through 5 have shift forks 2A through 5A respectively, and the shift shaft 5 has a bracket 53 intervening a spring 51. When a speed change gear ratio is commanded, an actuator comes to a state in which a piston rod 11 is most retracted, and a shift shaft 5 is selected. When the shift shaft 5 moves, the bracket 53 begins to compress the spring 51 to move the shift fork 5A, and a reverse gear engagement is realized. Thus, the shifting of plural number of shift shafts each of which has a different amount of shift can be enabled by a single shift actuator.

Description

[Detailed Description of the Invention] [Industrial Application Field] Even when a plurality of shift shafts have different shift amounts, a single actuator having a single shift amount is used to adjust each shift amount. The present invention relates to a shift operation mechanism for a transmission that can be shifted accordingly.

, [Foreground technology] As a shift operation mechanism of a vehicle transmission, for example, a predetermined shift shaft is selected via a control shaft by the operation of a select actuator (for example, a pneumatic type), and the selected shift shaft is transferred to the shift actuator. By shifting to the gear direction of the selected transmission ratio (including reverse drive) by (e.g. pneumatic),
A device in which a predetermined speed change operation is performed has been proposed.

According to the shift operation mechanism of this transmission, for example, in the case of a 6-speed transmission mechanism, two control shafts and four shift shafts are provided, and each control shaft corresponds to two shift shafts. However, one of the two corresponding shift shafts is selected by operating one of the two selection actuators. On the other hand, three of the four shift shafts are
Each gear is shifted by a shift actuator to obtain two speed ratios, and the remaining shift shaft can be shifted in the direction of the reverse gear.

[Problem that the invention seeks to solve]

However, according to the shift operation mechanism of this transmission, for example,
If the shift amount of the reverse gear shift fork and the other forward shift forks are different, if you try to shift using a single shift actuator with the same shift amount, the same shift amount will be used. Since the actuator must be constructed so that it can take a plurality of shift positions in the shift direction, the mechanism of the actuator becomes complicated.

On the other hand, if two shift actuators with different shift amounts in the same direction are used, there will be disadvantages such as an increase in size and cost.

[Means and effects for solving the problem] The present invention has been made in view of the above, and it is possible to perform multiple shifts with different shift amounts by a single shift actuator having a single shift amount in one direction. In order to shift the shaft, a shift operation of a transmission is made in which the shift stroke of the shift shaft having a small shift amount is slipped by the shift amount obtained by subtracting the small shift amount from the shift amount of the shift actuator to absorb the shift difference. It provides a mechanism.

〔Example〕

Hereinafter, a shift operation mechanism for a transmission according to the present invention will be explained in detail.

1 to 2 (a) and (b) show an embodiment of the present invention, in which inside a case 1 there are four shift shafts 2, 3, 4.5 arranged in parallel, and a long shaft. Two control shafts 6.7 are provided which are arranged in parallel and offset in the width direction. Shift shaft 2 is for 5th and 6th speeds, shift shaft 3 is for 3rd and 4th speeds, and shift shaft 4 is for 1st speed.

The second-speed shift shaft 5 connects the reverse gear ratios, and each of the shift shafts 2 to 5 shifts a sleeve (not shown) of the gear connection part in the direction of a predetermined speed ratio. shift fork 2A, 3A,
4A and 5A (only the fork 3B of the shift fork 3A is shown). The shift shaft 5 has a bracket 53 (having a spring engagement step 53) fixed to the shift fork 5A by a spring pin 52 via a spring 51, and the shift fork 5A is slidably engaged with the shift shaft 5. and has an inner notch 54 at the front stage in the shift direction, and a spring pin 56 that passes through the shift shaft 5 and whose head 55 engages with the notch 54 is provided in the notch 54. It is provided. on the other hand,
The control shaft 6.7 is connected to the shift shafts 2 and 3.
A ball member 1 has select levers 8 and 9 protruding between the shift shafts 4 and 5 and receives the piston movement of piston rods io and it, which will be described later.
2.13 with three positions of the piston rod 10
．． The piston 11 rotates around its axis to rotate the select levers 8 and 9 left and right by a predetermined angle.

The aforementioned shift shafts 2 to 5 are connected to the select lever 78.
It has engaging surfaces 2a to 5a that engage with it by rotation of 9. The piston rod 10.11 is moved by the actuator 14.15 for selection, and the groove 16al1
It has an engaging member 16.17 at its tip which engages with the ball member 12.13 via 7a. On the other hand, the control shaft 6.7 is connected by a connecting member 18 so that they can move together, and the control shaft 7 is continuous with the piston rod 20 of the shift actuator 19. Select actuator 15
is a cylinder 21 having a shoulder portion 21a.

It has a first piston 22 that is provided in the piston loft 11 and has a shoulder 22a, and a second piston 23 that is loosely fitted around the outer periphery of the first piston 22 and whose tip has a shape that fits the shoulder 22a. (Description of the illustrated backing etc. is omitted).

Note that the selection actuator 14 and the shift actuator 19 have the same configuration as the selection actuator 15, so a description thereof will be omitted, and in FIGS. 1 and 2, parts that are not directly related to the operation of the present invention are The explanation was omitted.

In the above configuration, the operation thereof will be explained with reference to FIGS. 3(a) and 3(b) to FIG. 5. Figure 4 shows speeds 1 to 6.
After selecting select points P0 to P in the direction of arrow A (corresponding to selection of shift shafts 2 to 5 with select lever 8°9), shift in the direction of arrow B. (Shift shaft 2
(corresponding to any one of the shift movements of 5 to 5), a gear connection with a predetermined transmission ratio is obtained.

For example, when a driver's seat commands a gear change ratio of the perspective view by operating a lever, the command is processed by a control section (not shown), and a control signal for controlling the selection actuator 15 is output from there. Through this control, piston control is performed within the cylinder 21, and the actuator 15
is in the neutral state shown in FIG.
3 is locked at the shoulder 21a) to the state shown in FIG. , and the shift shaft 5 is selected. Next, when a control signal for controlling the shift actuator 19 is output from the control section, piston control is performed within the cylinder, and the actuator 19 changes from the state shown in FIG. 2(A) to the state in which the piston rod 20 protrudes. As a result, the control shaft 7 moves in the direction of the arrow [Fig. 2 (a), (b)].

When the control shaft 7 moves, the movement is transmitted to the shift shaft 5 via the select lever 9, and the shift shaft 57 moves in the direction of the arrow. When the shift shaft 5 moves, the bracket 53 fixed by the spring pin 52 begins to compress the spring 51 (at this time, the shift fork 5A is not moved by the shift shaft 5 due to the sliding engagement), and the spring engagement stage 53A When the tip of the shift fork 5A presses the end of the shift fork 5A, the shift fork 5A starts moving in the direction of the arrow, and reverse gear connection is achieved via a gear connection sleeve (not shown) [see Figure 3 (Illustrated)]. ) to FIG. 3(B)] In this state, as shown in FIG. 3(B), the inner part 54A and the head 5
A gap G having a length equal to the difference in stroke between the shift actuator 19 and the shift fork 5A is created between the shift actuator 19 and the shift fork 5A.

Next, when a command is given to release the reverse gear connection, the control shaft 7 moves to the neutral position (in the opposite direction of the arrow), thereby causing the shift shaft 5 to move in the opposite direction of the arrow. By this, spring pin 5
When the head 55 of the shift fork 5A begins to engage with the inner part 54A of the notch 54 of the shift fork 5A, the shift fork 5A also begins to return to the neutral position, and the reverse gear connection is released.

〔Effect of the invention〕

As explained above, according to the shift operation mechanism of the transmission of the present invention, the shift stroke of the shift shaft having a small shift amount is slipped by the shift amount obtained by subtracting the small shift amount from the shift amount of the shift actuator. Since the difference is absorbed, a plurality of shift shafts having different shift amounts can be shifted by a single shift actuator having a single shift amount in one direction.

[Brief explanation of the drawing]

1 to 5 show an embodiment of the present invention, in which FIG. 1 is a sectional view showing the relationship between a control shaft and a shift shaft, FIG. 2 (A) is an overall plan view, Second
Figure (B) is an overall side view, Figure 3 (A) is an explanatory diagram showing the main parts in the neutral state, Figure 3 (B) is an explanatory diagram showing the main parts in the operating state, and Figure 4 is the gear shift diagram. Ratio pattern diagram, 5th
The figure is an explanatory diagram for operating the actuator. Explanation of symbols

Claims (1)

[Scope of Claims] A shift operation mechanism for a transmission including a plurality of shift shafts each having a shift fork having a first shift amount that is predetermined and a second shift amount that is smaller than the first shift amount, a shift fork that is provided on a shift shaft and that slips when the shift shaft moves and engages and moves in a predetermined relative positional relationship when the shift shaft moves in the opposite direction; and with respect to the shift fork. a bracket fixed to the predetermined shift shaft with an interval at least equal to the difference between the first and second shift amounts via an elastic member at a position opposite to the shift direction; When the single shift actuator having a first shift amount operates in the shift direction, the bracket compresses the elastic member to move the shift fork in the shift direction, and the single shift actuator moves in the neutral direction. 1. A shift operation mechanism for a transmission, characterized in that when operated, the shift fork is moved in the neutral direction by engagement movement between the predetermined shift shaft and the shift fork.