JPS6229251B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power shift device that easily performs a shift operation of a transmission of a large vehicle or the like.

[Prior Art] As shown in FIG. 1, a conventional device of this type is
A shift lever 2 that is linked to a gear shift lever 4 supported on the vehicle body by a ball joint 3 is connected to a rod 7 of a fluid pressure actuator 10, and when the resistance force applied to the shift lever 2 exceeds a predetermined value, the servo control valve 1 is activated.
4 forms a fluid pressure circuit of the fluid pressure actuator 10, and is configured to apply an assisting force to the shift lever 2.

In the fluid pressure actuator 10, a piston 9 is fitted into a cylinder 12 to partition chambers 13 and 8, and fluid inlets 5 and 6 facing each chamber 13 and 8 are communicated with a control valve 14 through an internal passage of a rod 7. On the other hand, one end of the rod 7 is connected to a fluid pressure source and the other end is connected to the atmosphere, and pressurized fluid is supplied from one fluid inlet 5 or 6 to one chamber 13 or 8 by operation of the control valve 14, and When the other chamber is opened to the atmosphere, the rod 7 connected to the piston 9 is actuated,
A light shift operation of the transmission can be achieved.

In this conventional power shift device, when the shift lever 2 is in the neutral position, the double-acting fluid pressure actuator 1 is activated.
0 piston 9 is positioned in the center of the cylinder 12, and the control valve 14 is operated by the load on the shift lever 2. Therefore, if a sudden shift operation is performed, the inside of the transmission will be damaged at the end of the shift. It hits the stopper hard and stops, and
If you perform a sudden return operation when downshifting, there is a risk that the gearshift operation mechanism will malfunction, such as going too far past the neutral position and misshifting to the opposite gear, and the structure is extremely complicated. Yes, it is very expensive.

[Problems to be Solved by the Invention] An object of the present invention is to have a simple configuration, and when the shift lever rotates by a predetermined angle relative to the power lever connected to the fluid pressure actuator, the control valve is activated and the fluid pressure actuator is activated. It is an object of the present invention to provide a power shift device for a transmission that allows easy shift operation.

[Means for Solving the Problems] In order to achieve the above object, the configuration of the present invention includes a rotating shaft that fixedly supports a shift lever that is engaged with a shift block and connected to a speed change lever, and A circumferential groove is provided on one side of the rotating surface of the power lever which is rotatably supported and connected to the hydraulic actuator, and a protruding piece that engages with the groove is provided on the other side, and the protruding piece is provided with the protruding piece that engages with the groove. It is equipped with a detent mechanism that positions it in the center of the groove.

[Operation] When the shift lever 27 is rotated by the speed change lever 21, the engagement of the ball 51 with the recess of the rotation shaft 28 in the detent mechanism is released, and only the rotation shaft 28 rotates. Then, the projecting piece 53 of the rotation shaft 28 is connected to the rod 3 of the fluid pressure actuator 35.
The circumferential groove 5 of the power lever 66 connected to 4
2, the power lever 66 is rotated, the control valve 38 is activated, and the driving force of the fluid pressure actuator 35 is transmitted to the shift lever 27. Since the fluid pressure actuator 35 does not operate at the same time as the shift lever 27 is rotated, the shift lever 2
Even if 7 is operated suddenly, accidents such as an excessive operating force acting on the synchronized mesh clutch mechanism or a misshift can be avoided.

[Embodiment of the Invention] As shown in FIG. 2, the gear shift lever 21 is supported on the vehicle body side by a ball bearing 22, and its lower end is connected to one end of a relay lever 24 via a link 23. The other end of the relay lever 24 supported by the vehicle body by the obstacle 25 is connected to the shift lever 2 by a link 26.
7 is connected. The shift lever 27 has a rotating shaft 28
is fixedly supported by the transmission 31 along with the rotating shaft 28.
The housing is rotatably supported.

The transmission 31 is connected to an engine (not shown) by a clutch 29.
The rotation of the input shaft 30 is transmitted to the output shaft 32 through the meshing of the gear train, and the shift rod 67 selects the meshing of the gears.
The end of the shift lever 27 is engaged with the shift block 67a. A power lever 66 is supported on the rotation shaft 28 so as to be relatively rotatable within a predetermined range, and the end portion of the power lever 66 is connected to the rod 34 of the hydraulic actuator 35.

As shown in FIG. 3, the fluid pressure actuator 35 has a cylinder 58 supported by a support shaft 37 so as to be swingable toward the vehicle body. The chambers 62 and 61 are partitioned by the piston 33 fitted in the cylinder 58, and the chamber 62
The piston 33 is normally biased to the right by the force of a spring 36 housed in the chamber 61, and when pressurized fluid is supplied to the chamber 61, the rod 34 is pushed to the left together with the piston 33. Pressurized fluid is supplied to chamber 61 from conduit 39 via control valve 38 .

The control valve 38 is connected to the cylinder 5 as shown in FIG.
A large-diameter valve chamber 74 and a small-diameter valve chamber 77 are provided on the right end wall of the valve 8, and a valve body 78 having a large-diameter portion and a small-diameter portion is fitted inside these.
An air vent 72 is provided at the inner end of the valve chamber 74, and the outer end is closed by a screw plug 73. A spring 60 is interposed between the screw plug 73 and the valve body 78.

An inlet 71 connected to the conduit 39 is provided in the valve chamber 77, and seal rings 7 are arranged on both sides of the inlet 71.
The small diameter portion of the valve body 78 is slidably fitted into the valve chamber 77 via the valve body 78 . An annular groove 75 is provided on the outer circumferential surface of the small diameter portion of the valve body 78 on the inner end side. The annular groove 75 is opened at its outer end via a radial passage and an axial passage 80, and is constantly communicated with the chamber 61 via a radial passage 79.

The conduit 39 is connected to an electromagnetic three-way valve 42 as shown in FIG.
It is connected to the fluid pressure source 70 via the conduit 40 when it is not energized, and to the atmosphere port 41 when it is energized.

As shown in FIG. 3, in order to detect the stroke of the piston 33, a hollow detection rod 57 is slidably supported on the left end wall of the cylinder 58.
It is designed to collide with each other alternately. and,
The switch 45 has a movable contact piece 56 that is biased by a spring on the circumferential surface having a recess of the rod 57.
It is supported by the wall of the cylinder 58.

The aforementioned electromagnetic three-way valve 42, switch 45, and switch 44 disposed on the speed change lever 21 are connected in series to a power source 43, as shown in FIG.

As shown in FIG. 3, a protruding piece 53 consisting of a key is fixed to the rotating surface, that is, the circumferential surface of the rotating shaft 28, while a recess for engaging the ball 51 is formed on the opposite side of the protruding piece 53. be done. The power lever 66 is rotatably supported by the rotation shaft 28, and its end is connected to the rod 34 by a pin 54. Rotation axis 28
A detent mechanism is provided between the power lever 66 and the rotating shaft 28, in which the ball 51 is engaged with the recess by a spring 64. power lever 66
A circumferential groove 52 is provided in the rotation surface, that is, the shaft hole, for engaging the protrusion 53. However, the protruding piece 53 and the groove 52 may be arranged oppositely to the rotating surface.

Next, the operation of the device of the present invention will be explained. Press the switch 44 in the neutral position shown in Figures 2 and 3,
Next, when the link 26 is pulled to the left by the shift lever 21, the switch 44 closes and the shift lever 2
7, the rotation shaft 28 is rotated counterclockwise. At this time, since the resistance force of the speed change operation mechanism is acting on the power lever 66, the ball 51 is disengaged and the power lever 66 does not rotate. Rotation axis 2
When the protruding piece 53 of No. 8 abuts against the upper edge of the groove 52, the power lever 66 is rotated.

On the other hand, since the switch 45 is in an open state, the electromagnetic three-way valve 42 is not energized, and the conduit 39 is connected to the fluid pressure source 70.

When the piston 33 moves slightly to the left, the valve body 78 of the control valve 38 is pushed to the left by the force of the spring 60, and the annular groove 75 is connected to the inlet 71. Therefore, pressurized fluid flows from the inlet 71 to the annular groove 75 to the passage 8.
0,79 to the chamber 61, and the piston 33
is pushed to the left against the force of the spring 36, and driving force is applied to the shift lever 27.

In this way, the shift lever 27 is rotated by the fluid pressure actuator 35, and the shift block 67 is rotated.
The shift rod 67 is actuated via the gearbox a, and the gears are brought into engagement with each other at a predetermined gear position by means of a synchronized mesh clutch mechanism in the transmission.

Immediately before the engagement of the synchronized clutch mechanism is completed, the detection rod 57 is pushed to the left by the piston 33, the movable contact piece 56 engages with the recess of the rod 57, and the switch 45, which had previously opened the circuit, is
closes. The electromagnetic three-way valve 42 is energized and the conduit 39
is cut off from the fluid pressure source 70 and communicated with the atmospheric port 41. Finally, when you let go of the gear shift lever 21,
Switch 44 opens the circuit.

Next, when the gear teeth of the transmission are disengaged and returned to the neutral position, when the switch 44 is pressed, the electromagnetic three-way valve 42 is energized and the chamber 61 of the fluid pressure actuator 35 is opened to the atmosphere. Next, when the shift lever 27 is returned to the position shown in FIG.
is pushed to the right by the force of the return spring 36, the power lever 66 rotates clockwise following the shift lever 27, and stops when the power lever 66 and the rod 34 are aligned in a straight line.

During this time, the valve body 78 of the control valve 38
3, the annular groove 75 communicates with the inlet 7.
1 to the atmosphere port 72, and the chamber 61 becomes a passage.
80, the annular groove 75, the valve chamber 74, and the atmosphere port 72 to be released to the atmosphere. Further, the detection rod 57 is returned to the state shown in FIG. 3 by the flange 55, and the switch 45 opens the circuit.

When the shift lever 21 is tilted in the opposite direction to the above case and the shift lever 27 is rotated clockwise, the rotation shaft 28 first pushes the ball 51 away from the power lever 66 and rotates, causing the protrusion to rotate. 53 is groove 5
2, the power lever 66 is rotated by the shift lever 27. And Rod 3
4 is pulled slightly to the left, the control valve 38 is actuated, the power lever 66 is rotationally driven by the fluid pressure actuator 35, and the upper end edge of the groove 52 is pulled slightly to the left.
3, the rotational driving force of the power lever 66 is transmitted to the shift lever 27, and a light shift operation is achieved.

[Effects of the Invention] As described above, the present invention includes a rotating shaft that fixedly supports a shift lever that is engaged with a shift block and connected to a speed change lever, and a rotating shaft that is rotatably supported by the rotating shaft and that is A circumferential groove is provided on one side of the rotating surface of the power lever connected to the pressure actuator, and a protruding piece that engages with the groove is provided on the other side, and a detent mechanism is further provided to position the protruding piece at the center of the groove. Because of this, a detent mechanism consisting of a ball and a recess provides a neutral position for the shift lever and power lever, and the driving force of the fluid pressure actuator is applied to shift operations in both directions of the shift lever, compared to conventional double-acting types. This simplifies the configuration of the fluid pressure actuator.

The shift lever and the power lever are rotatably engaged by the engagement of the projecting piece and the circumferential groove so that they can freely rotate by a predetermined angle, and the fluid pressure actuator is activated after the shift lever has been rotated by a predetermined angle. The shift operation is performed by manual operation force, and the driving force of the fluid pressure actuator is applied at the stage (stroke) when the synchronized mesh clutch mechanism is fully engaged, which is the most burdensome stage, so even if sudden shift operations are performed,
No excessive force is applied to the synchronized mesh clutch mechanism.

Also, when returning the shift lever to the neutral position,
Since the driving force of the fluid pressure actuator does not act, the shift lever does not go too far due to fluid pressure and miss-shift to the opposite gear shift, unlike in the conventional example.

Furthermore, the fluid pressure actuator is returned by the force of the spring and stops when the rod and power lever are aligned in a straight line (dead center), so misshifts due to overshooting are also prevented at this point.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a conventional power shift device for a transmission, FIG. 2 is a schematic configuration diagram of a power shift device for a transmission according to the present invention, and FIG. 3 is an enlarged view of the main parts of the device. FIG. 4 is a side sectional view of the control valve of the device. 21: Gear shift lever, 27: Shift lever, 2
8: Rotation axis, 33: Piston, 34: Rod, 3
5: Fluid pressure actuator, 36: Spring, 38:
Control valve, 42: Electromagnetic three-way valve, 44, 45: Switch, 51: Ball, 52: Circumferential groove, 53: Protrusion, 58: Cylinder, 66: Power lever, 6
7: Shift rod, 67a: Shift rod 7, 7
0: Fluid pressure source.

Claims (1)

[Claims] 1. A rotating shaft that fixedly supports a shift lever that is engaged with a shift block and connected to a speed change lever;
A circumferential groove is provided on one side of the rotating surface of the power lever supported by the rotating shaft so as to be freely rotatable and connected to the hydraulic actuator, and a projecting piece that engages with the groove is provided on the other side, and A power shift device for a transmission, comprising a detent mechanism that positions the protrusion at the center of the groove.