JP2506273Y2 - Mechanical meshing clutch switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a mechanical meshing clutch applied to a transmission of a diesel driven vehicle.

(Prior art example) FIG. 2 shows an example of a transmission using a pawl clutch as a mechanical meshing clutch, in which rotation from an input shaft 1 passes from an input gear 2 through an intermediate gear 3 meshing therewith to an intermediate gear. A low speed gear 5 and a high speed gear 6 are rotatably supported on the intermediate shaft 4 via bearings. The low-speed gear 5 and the high-speed gear 6 mesh with the low-speed driven gear 8 and the high-speed driven gear 9, which are integrated with the output shaft 7, respectively, and the intermediate shaft 4 includes a claw clutch provided on the opposite side of the low-speed gear 5 and the high-speed gear 6. A cylindrical body 14 having claws 12 and 13 of a claw clutch that engages with the claws 10 and 11 on both sides is spline-fitted between the low-speed gear 5 and the high-speed gear 6 so as to be slidable in the axial direction. Claw when sliding to the right in the figure
The rotation of the intermediate shaft 4 is transmitted to the low-speed gear 5 by meshing with 10 and 12, and when the claws 11 and 13 mesh with each other when sliding to the left, the rotation of the intermediate shaft 4 is transmitted to the high-speed gear 6, respectively. It is output as low-speed or high-speed rotation to the output shaft 7 via the driven gears 8 and 9 that mesh with each other.

As described above, the means for operating the cylinder 14 to change the shift speed is performed by operating the fork 17, which is inserted and slid in the outer peripheral groove 16 of the cylinder 14, with the cylinder driven by the pressure fluid. It

The third shows the cylinder of a conventional pressure fluid drive, fitted to the tip of the fork 17 ₁ to the outer peripheral groove 16 of the cylindrical member 14, fixed at the other end to the piston rod 18, to the piston rod 18 is symmetrical The pistons 19 and 20 are firmly fixed and slidably inserted into the cylinders 21 and 22, respectively.
The forks 17 ₁ are maintained in the neutral position by receiving a pressing force in the central direction via the springs 25 and 26 that abut the inner ends 28 and 24 of the members 21 and 22, respectively. Each of the valve chambers 27 and 28 of the cylinders 21 and 22 is provided with ports 29 and 30 communicating with the working fluid supply line, and when the working fluid is supplied to the port 29, the piston 19 is pushed to the right in the drawing. Under the pressure, the piston rod 18 is moved to the right against the leftward pressing force of the spring 26 until the protrusion 31 of the piston 20 contacts the inner end 24. As a result, the piston rod 18 and the 12 nails 10 of nail clutch moving cylinder 14 to the right via the integral of the fork 17 ₁ occlusion, as described above, the low-speed rotation is transmitted to the output shaft.
Conversely, when working fluid is applied to port 30, the cylinder 14
Moves in the opposite direction to the above to engage the claws 11 and 13, and the high speed rotation is transmitted.

(Problems to be solved by the invention) In such a conventional mechanical meshing clutch switching device, two cylinders and a valve chamber are required to push the left and right pistons, and each valve chamber has a respective one. Since the return spring is incorporated, the volume of the cylinder becomes large, and the housing of the transmission for accommodating the return spring also becomes large, which leads to an increase in weight and an increase in size of the device. Further, since the movement of the piston is performed against the pressing force of the spring, a high-pressure working fluid that opposes the spring force is required, and when the fluid pressure drops due to a failure of the working fluid supply source, the pawl It is possible that the engagement of the teeth becomes uncertain and the nail is damaged. Furthermore, if there is such a thing, when supply of the hydraulic fluid is cut off, the forks 17 _1, from both directions by receiving the pressure of the spring 26 and 25 become a neutral position, the Izure claw clutch God When the situation is solved, the power transmission is cut off and it becomes impossible to continue the operation. In addition, a switching device has been proposed in which a piston in a single cylinder is slid in the axial direction to switch to three positions, but when the neutral position is maintained, two fluid chambers facing each other are provided via the piston. At the same time, the working fluid is supplied to fix the piston position.When an abnormality occurs in the working fluid supply passage of one fluid chamber and the fluid pressure drops, the pressure balance is lost and the neutral state cannot be maintained. There is a risk that.

(Means for Solving the Invention) In order to solve the above drawbacks, in the present invention, a cylindrical body in which a low speed gear and a high speed gear that are rotatably supported are spline-fitted so as to be slidable in the axial direction. Is provided, by sliding this cylinder in the axial direction, the engagement and disengagement of the low-speed gear and the high-speed gear and the disengagement of the both gears at the neutral position, the claws of the meshing clutch are To the forks that are integrally provided on the opposing parts and integrally connected to the cylindrical body,
A piston rod that drives this in the axial direction is fixed, and two fixed pistons are fixed to the piston rod so as to be adjacent to each other in a single cylinder. The fixed piston has an outer peripheral surface and an inner peripheral surface of the cylinder. An annular floating piston having a locking portion that slidably contacts in a direction and abuts on the opposite side surface of the fixed piston is provided, and the fixed piston and the floating piston allow the first valve chamber, the second valve chamber, and the inside of the cylinder to move. Third
It is divided into three valve chambers and provided with operating pressure supply ports communicating with these valve chambers, and the operating pressure fluid is supplied only to the supply port of the second valve chamber at neutral to fix the locking part of the floating piston. It is characterized in that it is structured such that it is locked to the side surface of the piston and the outer surface of the floating piston abuts on the inner end of the cover that closes both ends of the cylinder.

(Embodiment) FIG. 1 shows an embodiment of the present invention. In FIG. 1, up to a reference numeral 17, reference is made to FIG. It is the same as described. That is, when the fork 17 is moved to the right in the figure, the claws 12 of the cylindrical body 14 mesh with the claws 10 of the low speed gear 5, and the cylindrical body 14 sprung into the intermediate shaft 4 from the intermediate shaft 4 moves at a low speed. The low speed rotation is output through the low speed driven gear 8 which is integrated with the gear 5 and the output shaft 7 (see FIG. 2) meshing with the gear 5. When the fork 17 is moved leftward, the pawls 11 and 13 are engaged with each other, and similarly, high speed rotation is output via the high speed gear 6 and the high speed driven gear 9.

In the present invention, the fork 17 is fixed to a piston rod 34 that slides in a single cylinder 33 in the axial direction, as shown in FIG.
Two fixed pistons 35 and 36 are fixed adjacent to each other at 34,
For each fixed piston 35 and 36, its outer circumference and cylinder 33
Of the annular shape in which the engaging portions 41 and 42 are provided so as to be slidably adhered to the inner peripheral portion of the slidable portion, and the facing side surfaces 37 and 38 are in contact with the facing side surfaces 39 and 40 of the fixed pistons 35 and 36. The floating pistons 43 and 44 are fitted and inserted, and the fixed pistons 35 and 36 and the floating pistons 43 and 44 divide the inside of the cylinder 33 into three first valve chambers 45, second valve chambers 46 and third valve chambers 47. Is operated by a meshing clutch switching device having working fluid supply ports 48, 49, and 50 communicating with the valve chambers 45, 46, and 47, respectively.

When the working fluid is supplied to the port 48 under such a configuration, pressure is applied to the first valve chamber 45, so that the fixed piston 35 moves rightward between the right end of the floating piston 44 and the end of the cylinder. The inner end surface of the cover 54 to be closed, the opposite side surfaces 37 and 38 of the floating pistons 43 and 44, and the side surface 39 of the fixed piston 35 and the locking portion 41 of the floating piston 43 all move until they come into contact with each other. , When the claws 10 and 12 are engaged with each other to output a low speed rotation and then the working fluid is supplied to the port 50, pressure is applied to the third valve chamber 47, so that the fixed piston 36 moves leftward. The left end of the floating piston 43 and the inner end surface of the cover 53 are the side surfaces 37 of the floating pistons 43 and 44 facing each other.
38 and the side 40 of the fixed piston 36 and the floating piston
Move until all the locking portions 42 of 44 come into contact with each other, and
13 and 13 are engaged, high-speed rotation is output, and port 49
When the working fluid is supplied to the second valve chamber 46, pressure is applied to the second valve chamber 46, so that the floating pistons 43 and 44 move until the outer surfaces 51 and 52 contact the inner end surfaces of the covers 53 and 54, respectively. At that time, the respective locking portions 41 and 42 of the floating pistons 43 and 44 are opposed to the side surfaces 39 of the fixed pistons 34 and 36, respectively.
Fixed piston 35
And 36 are fixed to the intermediate position, and the transmission is cut off by maintaining the cylindrical body 14 on both the low speed side and the high speed side in the neutral position where the claws are disengaged.

As the above-mentioned working fluid, pressure air generally used for a vehicle brake or the like can be used.

The switching control of the supply of the working fluid is performed by turning on / off the switching solenoid valve, and this operation gives a signal that detects the rotation speed of the engine and the rotation speed of the output shaft to the electronic control unit. This is performed when the engine governor is controlled by an output signal from the electronic control unit so that the meshing clutches are synchronized, and a substantially synchronized signal is detected.

Although the case where the meshing clutch is the claw clutch has been described in the above embodiment, the spline clutch can be similarly operated and is included in the present invention.

(Effect of the Invention) Since the present invention has a configuration in which the switching operation of the mechanical meshing clutch is performed by the two sets of the fixed piston and the floating piston which are adjacent to each other, only one cylinder is required and the number of parts of the switching device is reduced. It becomes compact, and the housing of the transmission that accommodates these is also made smaller, and the entire switching device including the housing is lighter and simpler, and can be manufactured at low cost. Furthermore, since it is sufficient to supply the pressure fluid to one valve chamber even in the neutral state, compared to the case where the pressure fluid is simultaneously supplied to the two valve chambers and the neutral position is maintained, the influence of the abnormality in the pressure fluid supply flow path is reduced. Hard to receive.

In addition, since the return spring is not required, the switching operation is smooth, and even if there is a pressure drop of the working fluid, the switching operation can be performed. Even if the supply is cut off, the meshing of the clutch is maintained, so there is also an effect that the transportation can be continued as it is.

[Brief description of drawings]

FIG. 1 shows a mechanical meshing clutch switching device 1 according to the present invention.
A sectional view of an embodiment, FIG. 2 is a sectional view of a gear type transmission to which a mechanical meshing clutch is applied, and FIG. 3 is a sectional view of a conventional mechanical meshing clutch switching device. is there. 4 ... Intermediate shaft, 5 ... Low speed gear, 6 ... High speed gear, 10,1
1,12,13 …… Claw, 14 …… Cylinder, 16 …… Outer circumferential groove, 17 ……
Fork, 33 …… Cylinder, 34 …… Piston rod,
35,36 …… Fixed piston, 41,42 …… Locking part, 43,44 ……
Floating piston, 45 ... First valve chamber, 46 ... Second valve chamber, 47 ...
… Third valve chamber, 48,49,50 …… Supply port, 53,54 …… Cover

Claims (1)

(57) [Scope of utility model registration request] 1. A spline fitting is slidable in an axial direction between a low speed gear (5) and a high speed gear (6) which are rotatably supported by an intermediate shaft (4) of a gear type transmission. The cylindrical body (14) is provided, and the cylindrical body (14) is slid in the axial direction to engage with and disengage from the low speed gear (5) and the high speed gear (6), and at the neutral position. ), The claws (10, 11, 12, 13) of the meshing clutch are integrally provided on the cylindrical body (14) and the facing portions of the both gears (5, 6) respectively, and the cylindrical body (14) A piston rod (34) for axially driving the fork (17) is integrally fixed to the fork (17), and two fixed pistons (35, 36) are attached to the piston rod (34).
Are fixed adjacent to each other in a single cylinder (33), and the outer peripheral surface of this fixed piston (35, 36) and the inner peripheral surface of the cylinder (33) are slidably contacted in the axial direction to form a fixed piston. (3
5,36) provided with an annular floating piston (43,44) having engaging portions (41,42) abutting opposite side surfaces of the stationary piston (35,36) and the floating piston (43,44). The inside of the cylinder (33) is divided into three parts, a first valve chamber (45), a second valve chamber (46) and a third valve chamber (47), and these valve chambers (45, 46,
47) Working pressure fluid supply port (48,49,50)
When the neutral piston is neutral, the working pressure fluid is supplied only to the supply port (49) of the second valve chamber (46) to lock the floating piston (4
1, 42) is locked to the side surface of the fixed piston, and the outer surface of the floating piston (43, 44) contacts the inner end of the cover (53, 54) that closes both ends of the cylinder (33). A mechanical meshing clutch switching device having the above-mentioned configuration.