JPH0527787B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION a. Field of Industrial Application The present invention relates to a transmission operating device that is mainly installed in the transmission of a large automobile, and particularly relates to a transmission operating device that is equipped with a transmission operating device that is installed on a shift piston rod. A free piston is provided, and the moving force of the fixed piston is increased by the advancement of the free piston, and the advancement of the free piston is stopped before the fixed piston reaches a gear engagement completion position. The present invention relates to a transmission operating device.

b. Prior art Transmission operating device 1 previously proposed by the applicant
(Utility Application No. 56-162462) is shown in FIGS. 5 and 6. This operating device 1 is usually attached to the upper part of a transmission 2 of a large automobile, etc., and the shift lever 3 of the operating device 1 is made to protrude downward into the transmission 2 from an opening 4 of the transmission housing. 3, the gear shift fork in the transmission 2 is operated to perform a desired gear shift.

Hereinafter, the structure of the operating device 1 will be briefly explained. As shown in FIGS. 5 and 6, the housing 5 of the operating device 1 is provided with two cylinder parts 6 and 7. As shown in FIGS. These two cylinder parts 6, 7
are provided so that their axes are perpendicular to each other, and a piston rod 8 for shift operation is inserted into one cylinder portion 6, and a piston rod 9 for selection operation is inserted into the other cylinder portion 7. A shift lever 3 is rotatably attached to the shift operation piston rod 8, and the tip of the shift lever 3 is connected to the selection operation piston rod 9 by a yoke 17.

The internal structures of the two cylinder parts 6 and 7 are exactly the same, so to explain one cylinder part 6, as shown in FIG. ing. A pair of left and right cylindrical free pistons 11 and 12 are disposed between the outer peripheral surface of the fixed piston 10 and the inner peripheral surface of the cylinder portion 6. This pair of free pistons 11, 12
are arranged slidably relative to the fixed piston 10 and the cylinder section 6, respectively, and are controlled by the air pressure introduced into the pair of pressure chambers 13 and 14 on both the left and right sides of the fixed piston 10. A pair of free pistons 11 and 12 are adapted to be driven in the left-right direction in FIG. In addition,
Supply and discharge of compressed air to and from the pair of pressure chambers 13 and 14 is controlled by a pair of solenoid valves 15 and 16.

At the rear of the pair of free pistons 11 and 12,
Pressing stepped portion 2 that presses the end of the fixed piston 10
1 and 22 are formed, respectively. Further, an inward flange portion 23 is formed approximately at the center of the inner peripheral surface of the cylinder portion 6, and the front end portions of the pair of free pistons 11 and 12 abut on this flange portion 23, respectively, as shown in FIG. Fixed piston in condition 1
0 is positioned at the neutral position (the position shown in FIG. 5). The stroke position of the piston rod 8 is determined by the stroke sensor 24.
Based on the detection result of the stroke sensor 24, the pair of electromagnetic valves 15 and 16 are controlled to open and close.

c Problems to be Solved by the Invention The conventional transmission operating device 1 is configured as described above, and when compressed air is introduced into one pressure chamber 13 or 14 by operating the solenoid valves 15 and 16, the fixed piston 10 moves to the right or left in FIG. 5, and the gear of the transmission is shifted. Also, when compressed air is introduced into both pressure chambers 13 and 14, the fifth
As shown in the figure, a fixed piston 10 is positioned at a neutral position by a pair of free pistons 11 and 12. Incidentally, it is known that the force required for a shift operation of the transmission 2 is greater when a gear is engaged than when a gear is pulled out. For example, if we continuously measure the load acting on the piston rod 8 when shifting the transmission 2 from 2nd to 3rd speed, the 7th
As shown in the figure, four waveforms a to d are obtained. Of these, waveform a shows the gear pull-out load, and waveform c shows the load at the time of synchro meshing of the transmission 2 (hereinafter referred to as "synchro load"), but the synchro load c is significantly larger than the gear pull-out load a. It can be seen that a load is required.

On the other hand, the output of the piston rod 8 is
As shown in the figure, the output e when the gear is taken out is slightly larger than the output f when the gear is put in. This is because when the piston rod 8 moves from the 2nd gear position to the neutral position, the forward force of the free piston 11 acts on the fixed piston 10, whereas when the piston rod 8 moves beyond the neutral position to the 3rd gear side. In this case, the free piston 11 is connected to the cylinder part 6.
This is because the moving force of the fixed piston 10 is reduced due to contact with the flange portion 23 of the fixed piston 10 .

Therefore, the size of the cylinder section 6, etc. is designed so that the output f of the piston rod 8 exceeds the synchro load c, but as the transmission 2 becomes larger, the synchro load c also increases, so the diameter of the fixed piston 10, etc. must be made larger. However, the space above the transmission 2 is usually considerably restricted due to the arrangement of floor plates, etc., and there is a limit to increasing the diameter of the cylinder portion 6.

Furthermore, when the piston rod 8 moves, for example, from the 2nd speed position to the 3rd speed position, the pressure in the pressure chamber 13 reaches its maximum at the position where the synchronized load c occurs (hereinafter referred to as the "synchronized position"), and the piston rod 8 passes through this synchronized load c. Then, as shown in FIG. 7, the load on the piston rod 8 suddenly decreases. For this reason, the piston rod 8 suddenly accelerates after passing the synchro load c, causing a bumping noise or wear at the stopper (not shown) of the piston rod 8 provided in the cylinder section 6 or on the gear side of the transmission 2. There is a risk that this may occur.

The present invention has been devised to effectively solve the above-mentioned problems, and its purpose is to increase the output of the shift operation piston rod at the synchronizing position without increasing the diameter of the cylinder portion of the conventional operation device. At the same time, the output of the shift operation piston rod is decreased after the shift operation piston rod passes the synchro position.

d Means for Solving the Problems An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG. 1 shows a cross section of the transmission operating device 30 similar to FIG.
The housing 5 is provided with a cylinder section 6 for shift operation and a cylinder section (not shown) for select operation with their axes at right angles to each other. Note that the cylinder portion for the selection operation may have the conventional structure shown in FIG. 6.

The housing 5 is also provided with another slightly smaller cylinder portion 31 on the side opposite to the side where the cylinder portion 6 is provided. Both ends of the shift operation piston rod 8 are slidably inserted into the cylinder parts 6 and 31, respectively. A fixed piston 10 is inserted into the outer periphery of the piston rod 8 within the cylinder portion 6, and the fixed piston 10 is fixed by a pair of left and right snap rings 32, 33. A pair of left and right cylindrical free pistons 11 and 12 are disposed between the outer peripheral surface of the fixed piston 10 and the inner peripheral surface of the cylinder portion 6. The pair of free pistons 11 and 12 are slidably disposed relative to the fixed piston 10 and the cylinder portion 6, respectively, and are configured to apply air pressure introduced into the pair of pressure chambers 13 and 14 on both left and right sides of the fixed piston 10. As a result, the fixed piston 10 and the pair of free pistons 11 and 12 are driven in the left-right direction in FIG. In addition, a pair of pressure chambers 1
The supply and discharge of compressed air to and from the pressure pumps 3 and 14 is controlled by a pair of electromagnetic valves 15 and 16 as pressure supply and discharge means. A pair of free pistons 1
Pressing step portions 21 and 22 for pressing the end portions of the fixed piston 10 are formed at the rear portions of the pistons 1 and 12, respectively. When compressed air is introduced into the pressure chamber 13 or 14 and the free piston 11 or 12 moves forward, the pressing step 21 or 22 is configured to press the end of the fixed piston 10.

An annular groove 34 is formed along the circumferential direction approximately at the center of the inner circumferential surface of the cylinder portion 6, and a stopper ring 35 is fitted into this groove 34 so as to be slidable in the left-right direction in FIG. There is. The inner peripheral portion of the stopper ring 35 extends slightly inward in the radial direction, and the front end portions of the pair of free pistons 11 and 12 are configured to be able to abut on the stopper ring 35, respectively. In addition, a pair of free pistons 11 and 12
When the front ends of the free pistons 11 and 11 are in contact with the stopper rings 35,
The twelve pressing steps 21 and 22 are also configured to abut against both ends of the fixed piston 10, respectively.

A pair of regulating portions 36 and 37 for regulating the forward movement of the pair of free pistons 11 and 12 are formed on both left and right side walls of the groove portion 34 . When the free piston 11 or 12 moves forward by l ₁ or l ₂ from the neutral position shown in FIG. ing.

The sizes of l ₁ and l ₂ are explained in detail with reference to FIG. 2. This figure 2 is a diagram showing the stroke amount of the piston rod 8 based on the neutral position. In the figure, L ₁ indicates the stroke amount up to the 3rd gear engagement completion position, and L ₂ indicates the stroke amount on the 3rd gear side. It shows the stroke amount to the synchronization completion position, L ₃ shows the stroke amount to the 2nd gear engagement completion position, and L ₄ shows the stroke amount to the 2nd speed side synchro completion position.

Here, l ₁ and l ₂ need only be within the range shown by the following formula. In other words, L ₂ <l ₁ <L ₁ L ₄ <l ₂ <L _3The above formula was explained using the case of applying gears to 2nd and 3rd gears as an example, but it applies to 4th and 5th gears. A similar relational expression holds true when shifting into gear.

Next, the structure of the other cylinder portion 31 will be explained. This cylinder portion 31 is provided to position the piston rod 8 to a neutral position, and a positioning piston 38 is disposed within the cylinder portion 31 so as to be slidable in the left-right direction in FIG. This positioning piston 38
On the front side (right side in Figure 1) is the piston rod 8.
An insertion hole 39 into which the end of the piston rod 8 can be inserted is formed on the inner surface of the insertion hole 39.
A contact surface 40 is formed on which the end of the contact surface 40 can come into contact. Note that the pressure receiving area of the positioning piston 38 is made slightly larger than the sum of the pressure receiving areas of the fixed piston 10 and the free piston 12.

On the other hand, a pressure chamber 41 is formed behind the positioning piston 38, and compressed air introduced into the pressure chamber 41 causes the positioning piston 38 to move rightward in FIG. Compressed air is supplied to and discharged from the pressure chamber 41 using a solenoid valve 4.
It is designed to be controlled by 2.

The three solenoid valves 15, 16 and 42 are attached to the operating device 30 according to the present invention as described above.
are each composed of a 3-way solenoid valve, and when the power is not energized (OFF), the pressure chambers 13, 14 and 41 are
The pressure chambers 13, 14, and 41 are respectively connected to the atmosphere, and when energized (ON), the pressure chambers 13, 14, and 41 are connected to a pressure source such as an air reservoir. The three solenoid valves 15, 16 and 42 are controlled to open and close based on detection signals from a stroke sensor attached to the piston rod 8.

Figure 3 shows the control status of the three solenoid valves 15, 16 and 42 and the load waveforms a to piston rod 8.
d is shown taking as an example the case of gear shifting from 2nd speed to 3rd speed, and as shown in the figure, the solenoid valve 15 is turned ON until the piston rod 8 moves to the gear extraction completion position. After that, it is controlled to turn OFF, and then turn ON again after the piston rod 8 reaches the neutral position. In addition, the solenoid valves 16 and 42 are turned OFF until the piston rod 8 moves to the gear extraction completion position, then turned ON, and then turned ON again after the piston rod 8 reaches the neutral position.
Each is controlled so that it is turned off.

e Operation The transmission operating device 30 is configured as described above, and the operation of the operating device 30 when shifting the transmission from 2nd speed to 3rd speed, for example, will be explained as follows.
First, based on the detection signal of the stroke sensor of the piston rod 8, the solenoid valve 15 is operated as shown in FIG.
is turned ON, and the solenoid valves 16 and 42 are maintained OFF. When the solenoid valve 15 is turned on, compressed air is introduced into the pressure chamber 13, and this pressure moves the fixed piston 10 and the free piston 11 from the left end position to the right in FIG. When the fixed piston 10 or the piston rod 8 moves to the right in this manner, the second gear is removed by the shift lever 3. At this time, the fixed piston 10 is pressed in the moving direction by the pressing step portion 21 of the free piston 11, so the piston rod 8
The output is large, and 2nd gear can be pulled out smoothly.

When the fixed piston 10 or the piston rod 8 moves to the gear extraction completion position, the solenoid valve 15 is turned off by the detection signal from the stroke sensor, and the solenoid valves 16 and 42 are turned on. As a result, the compressed air in the pressure chamber 13 is discharged to the outside, and the compressed air is introduced into the pressure chambers 14 and 41. When compressed air is introduced into the pressure chamber 41, the positioning piston 38 moves rightward as shown in FIG. 1 due to this pressure, comes into contact with the housing 5, and stops. On the other hand, when compressed air is introduced into the pressure chamber 14, this pressure pushes the fixed piston 10 and the free piston 12 leftward in FIG. 40, thereby positioning the piston rod 8 in the neutral position.

When the piston rod 8 moves to the neutral position, the solenoid valve 1 is activated by the detection signal of the stroke sensor.
5 is turned ON again, solenoid valves 16 and 42
turns off again. When the solenoid valve 15 is turned on, compressed air is introduced into the pressure chamber 13, and the solenoid valve 1
When the pressure chambers 6 and 42 are turned off, the compressed air in the pressure chambers 14 and 41 is discharged to the outside. As a result, the fixed piston 10 and the free piston 11 move into the pressure chamber 13.
The pressure causes it to move to the right from the neutral position shown in FIG. Fixed piston 1 like this
When the piston rod 8 moves to the right, the shift lever 3 synchronizes the transmission. At this time, the fixed piston 10 is pressed in the moving direction by the pressing stepped portion 21 of the free piston 11, so that the output of the piston rod 8 is large and synchronization of the transmission can be completed smoothly.

When the fixed piston 10 and the free piston 11 move more than l ₁ to the right from the neutral position shown in FIG. Therefore, the forward movement of the free piston 11 is restricted by the stopper ring 35, and the fixed piston 10 moves further to the right away from the pressing step 21 of the free piston 11. When the fixed piston 10 or the piston rod 8 moves further to the right in this manner, the shift lever 3 engages the third gear. At this time, since the fixed piston 10 is not pressed in the moving direction by the free piston 11,
The output of the piston rod 8 has become relatively small. Therefore, unlike the conventional operating device 1, the piston rod 8 does not suddenly accelerate after passing the synchro load c, and the third gear can be engaged quietly. Therefore, there is no occurrence of a bumping noise or wear on the stopper (not shown) of the piston rod 8 or on the gear side of the transmission.

The operation of the operating device 30 when shifting gears from 2nd gear to 3rd gear has been explained above.
A similar operation is performed when shifting gears to 4th gear, from 4th gear to 5th gear, or from 5th gear to 4th gear.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment and can be modified in various ways. For example, in the above embodiment, the forward movement of the free pistons 11 and 12 is restricted by the stopper ring 35 and the restriction parts 36 and 37 of the groove part 34, but as shown in FIG. An inwardly directed flange portion 45 is formed at the portion, and both left and right side surfaces of this flange portion 45 serve as regulating portions 46, 47, and the forward movement of the free pistons 11, 12 is directly regulated by the regulating portions 46, 47. You can do it like this. In this case, the pair of free pistons 11 and 12 are provided with cutout steps 48 and 49.
, so that the pair of free pistons 11 and 12 can move forward by l ₁ or l ₂ further from the neutral position.

f. Effects of the Invention As described above, the present invention includes a pair of free pistons arranged around the outer periphery of a fixed piston attached to a piston rod for shift operation, and when the free piston moves forward, the free piston is fixed by the pressing part of the free piston. The moving force of the fixed piston is increased by pressing the piston in the forward direction, and after the fixed piston passes the synchronization completion position but before reaching the gear engagement completion position, a free piston is provided on the inner peripheral surface of the cylinder part. Since the regulation is controlled by the regulating section, the output of the piston rod at the synchronizing position can be increased without increasing the diameter of the fixed piston or cylinder section, and this makes it possible to increase the output of the piston rod at the synchronizing position. It is possible to reduce the size and also to smoothly synchronize the transmission. Moreover, after synchronization of the transmission is completed, the forward movement of the free piston is restricted and the output of the piston rod is reduced, so when compared to a conventional booster with the same output, the piston rod suddenly accelerates after passing the synchronized load. The transmission gear can be engaged quietly without having to do so. Therefore, there is no occurrence of a bumping noise or wear on the stopper of the piston rod or on the gear side of the transmission.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view of a transmission operating device, and FIG. 2 is a schematic diagram for explaining the stroke amount of the piston rod. , FIG. 3 is a schematic diagram for explaining the control situation of three electromagnetic valves, and FIG. 4 is a longitudinal sectional view similar to FIG. 1 showing a modification of the present invention.
5 to 7 show a conventional transmission operating device, in which FIG. 5 is a longitudinal cross-sectional view of the operating device, FIG. 6 is a cross-sectional view taken along the - line in FIG. 7th
The figure is a schematic diagram for explaining the load and output of the piston rod. 5...Housing, 6...Cylinder part, 8...
Piston rod for shift operation, 10... Fixed piston, 11, 12... Free piston, 13, 1
4... Pressure chamber, 15, 16... Solenoid valve (pressure supply/discharge means), 21, 22... Pressing step section (pressing section), 30
...Transmission operating device, 34...Groove, 36,3
7, 46, 47... regulating section, 45... flange section.

Claims (1)

[Scope of Claims] 1. A transmission operating device in which a shift lever is driven by fluid pressure, comprising: (a) a housing having a cylinder portion; (b) one end of which the shift lever is attached; a piston rod slidably inserted into the cylinder; (c) a fixed piston fixed to the piston rod in the cylinder; and (d) between the inner peripheral surface of the cylinder and the outer peripheral surface of the fixed piston. , a pair of free pistons disposed so as to be able to move forward and backward along the axial direction of the cylinder portion; (f) a pair of pressure chambers formed on both sides of the fixed piston; (g) pressure supply and discharge means for supplying and discharging fluid pressure to and from the pair of pressure chambers; (h) a regulating section provided on the inner circumferential surface of the cylinder section, which comes into contact with the free piston to restrict its advancement after the fixed piston passes the synchronization completion position but before reaching the gear closing completion position; A transmission operating device characterized by comprising: and.