JPH0514041Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention particularly relates to a transmission mechanism suitable for shifting and switching between forward and backward movement of vehicles such as agricultural vehicles, transport vehicles, and snowplows.

BACKGROUND OF THE INVENTION A conventional transmission is provided with a clutch lever for changing the speed of the vehicle, and is also provided with a forward/reverse switching lever separate from the clutch lever for switching the vehicle forward or backward.

Furthermore, a system in which gear shifting and forward/forward switching are performed by the same operating tool has been proposed in Japanese Utility Model Application Publication No. 162524/1983.

Problems to be Solved by the Invention However, in conventional transmissions, gear shifting and forward/reverse switching operations must be performed separately using a clutch lever and a forward/reverse switching lever; The switching operation using the lever is troublesome, and the forward/reverse switching lever can be switched even if the clutch lever is not on the low speed side, so there is a risk of an accident due to a mistake in switching the forward/reverse switching lever.
It was also the cause of transmission failure.

In addition, the one described in Utility Model Application Publication No. 55-162524 is
It uses an axial plunger type pump that changes the discharge direction and discharge amount of pressure oil by changing the swash plate angle, and is complex and expensive in structure.

The purpose of the present invention is to address the above-mentioned problems and to
By rotating the gear shift lever using the end of the gear shift shaft of the wheel as a fulcrum, the gear shift shaft rotates in the same direction as the gear shift lever rotates, and the rotation transmission mechanism converts the rotation of the gear shift shaft into rotational and linear motion. The transmission is transmitted to the conversion mechanism, and the rotation/linear motion conversion mechanism changes the rotational motion of the gear shift shaft into linear motion, and the rotation/linear motion conversion mechanism switches the gear shift device of the wheel to the low speed side or high speed side, supporting the gear shift lever. The gear lever rotates in a plane that includes the gear shift lever and the gear shift shaft using the body as a fulcrum, and the gear shift shaft moves in the axial direction as the gear shift lever rotates relative to the support body, and the forward/reverse switching device of the wheel It can be switched to the forward or reverse side by linear movement in the direction, and the transmission can be shifted and forward/reverse operation can be performed with a single shift lever without using a pump, and the structure is simple and does not require a power unit.
Unlike conventional methods, it is no longer necessary to perform gear shifting and forward/reverse switching operations using the clutch lever and forward/reverse switching lever separately, and the shifting and forward/reverse switching operations using the gear lever are no longer cumbersome.
If the support body does not set the gear shift lever to the low speed side where it is restrained, the gear shift lever cannot be used to switch between forward and backward movement, which eliminates accidents caused by mistakes in shifting the gear lever, resulting in high safety. It is an object of the present invention to provide a speed change mechanism for a transmission capable of suppressing a return to a low speed side using a rotation/linear motion conversion mechanism.

Means for Solving the Problems The speed change mechanism of the transmission of the present invention is provided with a support body that closes the low speed operation side of the speed change lever and opens the high speed operation side of the speed change lever, and the end of the speed change lever A gear shift shaft of a wheel is mounted horizontally so as to be freely rotatable and movable in the axial direction in a direction intersecting this, and an end of the gear shift lever is attached to an end of the gear shift shaft, and the gear shift lever is mounted relative to the gear shift shaft. The speed change lever and the speed change shaft are connected to each other so as to be rotatable in a plane including the speed change lever and to be integrally rotatable in a plane orthogonal to the speed change shaft, and to transmit rotational movement of the speed change shaft to the speed change shaft via a rotation transmission mechanism. The rotation/linear motion conversion mechanism is connected to a speed change device for the wheels that is moved by the rotational motion of the speed change shaft, and the speed change shaft is connected to the speed change device for the wheels that is moved by the rotation motion of the speed change shaft. It has a structure characterized in that it is connected to a forward/reverse switching device for the wheels that move by linear motion in the axial direction of the shaft.

Operation By rotating the gear shift lever using the end of the gear shift shaft of the wheel horizontally mounted in the direction intersecting the gear lever as a fulcrum, the gear shift shaft rotates in the same direction as the gear shift lever rotates, and the gear shift shaft The rotation is transmitted to the rotation/linear motion conversion mechanism via the rotation transmission mechanism, and the
The linear motion conversion mechanism converts the rotational motion of the transmission shaft into linear motion, and the wheel speed change device connected to the rotational/linear motion conversion mechanism is switched to a low speed side or a high speed side by the rotational/linear motion conversion mechanism, and the transmission is activated. The gear change operation is performed by the gear shift lever, and the rotation/linear motion conversion mechanism suppresses the gear shift device from returning from the high speed side to the low speed side.

In addition, at the low speed side where the support body disposed on the gear shift lever restrains the gear shift lever, the gear shift lever rotates about the support body as a fulcrum in a plane that includes the gear shift lever and the gear shift shaft, and the gear shift shaft rotates around the gear shift lever. The wheels move in the axial direction as they rotate with respect to the support, and the forward/reverse switching device of the wheels is switched to the forward or reverse side by the linear movement of the gear shift shaft in the axial direction. Unless the shift lever is set to the low speed side where the support body restrains the shift lever, the shift lever cannot be used to switch between forward and backward movement.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings. In FIG. 1, 1 is a gear shift lever, and the gear shift lever 1 has a low-speed operation lever as shown in FIG. A support body 7 is disposed with the side closed and the high-speed operating side open, and at the end of the gear shift lever 1, a gear shift shaft 4 of a wheel is rotatably moved in the axial direction and horizontally at the end of the gear shift lever 1. The transmission shaft 4
An end of the speed change lever 1 is connected to the end of the shift lever 1 so as to be rotatable in a plane including the speed change lever 1 and the speed change shaft 4, and to be integrally rotatable in a plane orthogonal to the speed change shaft 4.

A cam 11 is connected to the speed change shaft 4 via a rotation transmission mechanism, and serves as a rotation/linear motion conversion mechanism that converts the rotational motion of the speed change shaft 4 into linear motion. The cam 11 is also connected to a speed change ring 14 which serves as a speed change switching device for the wheels that move due to the rotational motion of the speed change shaft 4, and the speed change shaft 4 is connected to a forward/reverse switching gear 19 which serves as a forward/reverse switching device for the wheels that move due to the linear motion of the speed change shaft 4 in the axial direction.

Below the longitudinal center of the gear shift lever 1, there is a
As shown in FIGS. 1 and 2, a U-shaped support 7 is disposed, an operating body 2 is provided at the upper end of the shift lever 1, and the support 7 is located on the low-speed operation side of the shift lever 1. The one facing the high-speed operation side is open.

As shown in FIG. 1, on the side of the lower end of the speed change lever 1, a speed change shaft 4 is disposed in the horizontal direction, and a large speed increasing gear 5 is disposed near the longitudinal center of the speed change shaft 4. One end and the other end of the speed change shaft 4 are rotatably supported by a bearing 6 and a bearing 6', respectively, and the speed increasing gear 5 is fixed to the speed change shaft 4.

A joint 3 is fixed to the other end of the speed change shaft 4, and the joint 3
The lower end of the gear shift lever 1 is rotatably supported on the shaft.

The gear shift lever 1 is rotated in the direction of arrow a in FIG. By restraining the shift lever 1, the shift lever 1 becomes the low speed side L, and by releasing the shift lever 1 from the support 7, the shift lever 1 becomes the high speed side H, and the shift lever 1 becomes the low speed side L or the high speed side H. It is now possible to perform gear shifting operations.

Further, the shift lever 1 is rotated in the direction of arrow b in FIG. Shift lever 1 on the forward side F or reverse side R, which is moved in the axial direction as it rotates.
It is now possible to perform forward and backward switching operations.

A rotary shaft 9 is rotatably mounted horizontally on the upper part of the speed change shaft 4, and a small speed increasing gear 8 that meshes with the large speed increasing gear 5 is disposed on the rotating shaft 9. gear 8
A cam 11 is disposed on the side of the cam 11, a lead groove 10 is formed on the outer peripheral surface of the cam 11, and both ends of the rotating shaft 9 are rotatably supported by bearings 12, 12'.
The speed increasing small gear 8 and the cam 11 are each fixed to the rotating shaft 9.

A rotation transmission mechanism that transmits the rotation of the speed change shaft 4 to the rotating shaft 9 includes a large speed increasing gear 5 and a small speed increasing gear 8.

A ring holder 1 is installed in the lead groove 10 of the cam 11.
3 is engaged, and the ring holder 13 is moved in the axial direction of the rotating shaft 9 along the lead groove 10 of the cam 11 by rotation of the cam 11.

A support shaft 15 is rotatably mounted horizontally on the upper part of the rotating shaft 9, and a speed change ring 14 is disposed on the support shaft 15 so as to be movable in the axial direction.
The gear ring 1 is rotatably supported by the gear ring 16'.
4 is held by a ring holder 13.

The speed change ring 14 is moved in the axial direction along the support shaft 15 via the ring holder 13 by the rotation of the cam 11, and the speed change between the high speed side H and the low speed side L is performed by the speed change ring 14. There is.

The cam 11 transfers the rotational movement of the speed change shaft 4 to the speed change ring 1.
It is designed to convert into linear motion of 4.

The speed change ring 14 has a tendency to return to the low speed side L from the high speed side H, and the lead angle of the lead groove 10 formed on the outer peripheral surface of the cam 11 is determined to suppress this.

The speed increasing gear 5 and the speed increasing small gear 8 have speed increasing ratios set so that the rotation angle of the speed change lever 1 matches the ratio of the amount of movement of the speed change ring 14 in the axial direction. 14, when the shift lever 1 is shifted from the low speed side L to the high speed side H, the shift ring 14 tries to return from the high speed side H to the low speed side L, but the shift ring 14 moves from the high speed side H to the low speed side. The return to L is suppressed by the cam 11.

A shift fork 17 is installed on the side of the speed increasing large gear 5.
A gear holder 18 is formed at the lower end of the shift fork 17, and the upper end of the shift fork 17 is rotatable and axially restrained on the transmission shaft 4. The shift shaft 4 is rotatable relative to the shift fork 17.

A support shaft 21 is rotatably mounted horizontally at the lower part of the speed change shaft 4, and a gear 19 for forward/reverse switching is mounted on the support shaft 21.
is arranged to be rotatable and movable in the axial direction, both ends of the support shaft 21 are rotatably supported by bearings 20, 20', and the forward/reverse switching gear 19 is held by the gear holder 18. .

The shift shaft 4 is moved in the axial direction by rotating the shift lever 1 in the direction of the arrow b in FIG. The forward/reverse switching gear 19 is moved in the axial direction along the support shaft 21 via the gear holder 18 of the shift fork 17, and the forward/reverse switching gear 19 is used to switch forward/backward on the forward side F or reverse side R. It is becoming more and more popular.

Next, the operation of this embodiment will be explained.

To change the speed using the shift lever 1 of the shift shaft, when the shift lever 1 is rotated in the direction of arrow c in FIG. 2 or in the opposite direction to the direction of arrow c in FIG. Gear shift lever 1
At the same time, the speed-increasing large gear 5 rotates in the same direction as the speed-changing shaft 4 rotates, and the speed-increasing small gear 8 meshes with the speed-increasing large gear 5 in the opposite direction. The rotating shaft 9 rotates together with the speed-increasing small gear 8 in the opposite direction to the speed change shaft 4, and the cam 11 rotates on the rotating shaft 9.
The ring holder 13 rotates in the same direction as the speed-increasing small gear 8 as
0 in the axial direction of the rotating shaft 9, and the speed change ring 14 moves in the axial direction along the support shaft 15 via the ring holder 13, moving the speed change ring 14 to the low speed side L or the high speed side H. , the speed change of the transmission is performed by the speed change ring 14, and the cam 11 suppresses the speed change ring 14 from returning from the high speed side H to the low speed side L.

In addition, when switching between forward and backward movement using the shift lever 1 of the transmission, first move the shift lever 1 in the direction of the arrow d in FIG. Alternatively, when rotating in the direction of arrow e, the shift shaft 4 moves in the axial direction via the joint 3 as the shift lever 1 rotates relative to the support 7, and at the same time the shift fork 17 moves in the axial direction together with the shift shaft 4. The forward/reverse switching gear 19 is connected to the gear holder 1 of the shift fork 17.
8 moves in the axial direction along the support shaft 21 and moves the forward/reverse switching gear 19 to the forward side F or the reverse side R, so that the forward/reverse switching of the transmission is performed by the forward/reverse switching gear 19.

Furthermore, as shown in FIG. 3, on the low speed side L where the support body 7 restrains the shift lever 1, the shift lever 1 is located in the center between the forward drive side F and the reverse drive side R, so that the transmission is The engine's output shaft is in the neutral N state where the rotation is 0, and by moving the gear shift lever 1 from the neutral N position in the direction of arrow d in Figure 1, the transmission moves forward at a low speed.
By moving the shift lever 1 from the neutral N position in the direction of arrow e in FIG. 1, the transmission enters the low speed reverse LR state.

Furthermore, by moving the shift lever 1 from the low speed forward LF position in the direction of arrow c' in FIG. Low speed reverse LR
By moving from the position in the direction of arrow c'' in Fig. 3, the transmission enters the high-speed reverse HR state in which the gear shift lever 1 is released from the support 7. This cannot be done unless the high speed side H is returned to the low speed side L.

Effects of the Invention As described above, according to the transmission mechanism of the present invention, by rotating the gear shift lever using the end of the gear shift shaft of the wheel as a fulcrum, the gear shift shaft responds to the rotation of the gear shift lever. At the same time, the rotation transmission mechanism transmits the rotation of the gear shift shaft to the rotation/linear motion conversion mechanism, and the rotation/linear motion conversion mechanism converts the rotation motion of the gear shift shaft into linear motion, so that the rotation of the wheel The speed change device can be switched to a low speed side or a high speed side by a rotary/linear motion conversion mechanism, and by rotating the speed change lever using the support as a fulcrum within a plane including the speed change lever and the speed change shaft,
The gear shift shaft moves in the axial direction as the gear shift lever rotates relative to the support body, and the forward/reverse wheel switching device can be switched to the forward or reverse side by linear movement of the gear shift shaft in the axial direction. You can change gears and change forward/backward without using the transmission.
Since the gear shift lever can be used, the structure is simple and no power unit is required, and there is no need to separately perform gear shifting and forward/reverse switching operations using the clutch lever and the forward/reverse switching lever as in the past. Changing the speed of the machine and forward/reverse using the gear lever is not troublesome, and the gear lever cannot be used to change the gear between forward and backward unless it is set to the low speed side where the support body restrains the gear lever. Accidents caused by mistakes can be eliminated, safety is high, and the rotational/linear motion conversion mechanism can suppress the gear shifting device from returning from the high speed side to the low speed side.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a transmission mechanism of a transmission according to an embodiment of the present invention, FIG. 2 is a side sectional view of the main part of FIG. 1, and FIG. FIG. 4 is a plan view showing a forward switching state. 1... Speed change lever, 2... Operating body, 3... Joint, 4... Speed change shaft, 5... Speed increasing gear, 6,
6'...Bearing, 7...Support, 8...Speed-up small gear, 9...Rotating shaft, 10...Lead groove, 11...
Cam, 12, 12'...Bearing, 13...Ring holder, 14...Speed ring, 15...Spindle, 1
6, 16'...Bearing, 17...Shift fork,
18... Gear holder, 19... Forward/forward switching gear, 20, 20'... Bearing, 21... Support shaft.

Claims (1)

[Scope of utility model registration request] The gear shift lever is provided with a support that closes the low speed operation side of the gear shift lever and opens the high speed operation side, and a support body is provided at the end of the gear shift lever so that the gear shift shaft of the wheel can be freely rotated in a direction intersecting the support body. horizontally movable in a direction, an end of the speed change lever is attached to an end of the speed change shaft, and the speed change lever is rotatable with respect to the speed change shaft within a plane including the speed change lever and the speed change shaft; , connected so as to be integrally rotatable in a plane perpendicular to the speed change shaft, and communicating with the speed change shaft via a rotation transmission mechanism a rotation/linear motion conversion mechanism that converts the rotational motion of the speed change shaft into linear motion; The rotation/linear motion conversion mechanism is connected to a speed change switching device for the wheels that moves by the rotational movement of the speed change shaft, and the forward and backward switching of the wheels moves the speed change shaft by linear movement in the axial direction of the speed change shaft. A transmission mechanism of a transmission, characterized in that it communicates with a device.