JPS6122017Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a speed change operation device for a riding vehicle, such as a tractor, equipped with a continuously variable transmission.

Conventional speed change control devices for passenger work vehicles include those operated solely by the pedal and those operated solely by the manual lever, but the former pedal operated type does not require the pedal to be pressed even when driving at a constant speed. There is the inconvenience of having to step into a constant state and maintain it.
In addition, in the latter type of manual lever type, the manual lever is generally configured to be able to be held fixed at any operating position via a friction holding mechanism, and while it is convenient to carry out the above-mentioned constant speed driving operation, it is also difficult to perform gear shifting operations. In particular, there was a danger that they would not be able to swiftly perform neutral maneuvers to avoid danger.

Therefore, a method has been developed in which a pedal and a manual lever are linked and arranged side by side, but in conventional devices, the manual lever is operated and moved by pedal operation against its frictional holding force. As a result, the pedal operation became extremely heavy, and the transmission sometimes did not return to neutral even if the pedal was released, and the manual lever was not operated unnecessarily due to the pedal operation. Due to the movement, the friction retaining mechanism wears out prematurely, making it difficult to maintain the position of the manual lever after long-term use.

In view of these circumstances, the present invention aims to provide a pedal and a manual lever side by side without causing the above-mentioned inconveniences, thereby achieving improved shift operability by providing the pedal and manual lever side by side. The purpose is to

The speed change operation device for a riding work vehicle according to the present invention pivots a mounting shaft of a manual lever for speed change operation, which has a male threaded portion at one end thereof, so as to be movable back and forth in the axial direction with respect to a fixed member, and the male threaded portion protruding from the fixing member, screwing a female thread member onto the protruding end thereof, and fixing a fixing member to the mounting shaft between the mounting portion of the manual lever for speed change operation and the fixing member; A cylindrical member that is linked to a speed change operation pedal of a continuously variable transmission is loosely fitted onto a mounting shaft between the fixed member and the fixed member, and a fixed member is provided between the fixed member and the cylindrical member. Equipped with a spring that biases in the direction of releasing the interlock between the and the cylindrical member,
Further, a clutch mechanism is provided which interlocks the fixing member and the cylindrical member by movement of the mounting shaft against the biasing force of the spring as the female threaded member screws; between the fixed member and the fixed member, one end of the cylindrical member that is interlocked with the fixing member as the female screw member screws is brought into contact with the fixed member, and the one end of the cylindrical member and the fixed member It is characterized by being equipped with a friction mechanism that increases the sliding resistance between the two.

In other words, if the female screw member is sufficiently loosened, the mounting shaft will be moved by the urging force of the spring to release the interlock between the fixed member and the cylindrical member by the clutch mechanism, and the pedal will be in a state of being separated from the lever. This allows quick pedal operation even though the pedal and manual lever are installed side by side.Moreover, by screwing the female threaded member, the clutch mechanism becomes interlocked, allowing the manual lever to be connected to the transmission. In conjunction, constant speed driving can be conveniently performed by lever operation. Moreover, when the female thread member is further screwed forward from the interlocking state, one end of the cylindrical member comes into contact with the fixed member while maintaining the interlocked state with the mounting shaft, and the friction mechanism causes the cylindrical member to swing relative to the fixed member. Since it can be fixed so that it cannot be moved, both the manual lever and the pedal are rendered inoperable, making it possible to prevent accidental high-speed operation due to accidental operation, which is safe.

Hereinafter, an embodiment of the present invention will be described based on the drawings. By the forward and downward rotational movement of the foot, the neutrally biased hydraulic continuously variable transmission 1 is actuated to the forward speed increasing side, and the backward and downward direction A tractor (an example of a riding work vehicle) equipped with a gear shift operation pedal 2 and a gear shift operation manual lever 3 that can operate the transmission device 1 to the reverse speed increasing side by stepping on and turning the pedal. In the speed change operation device, the mounting shaft 4 of the manual lever 3 is rotated and slid by a downward U-shaped fixing member 7 formed with an operation movement guide groove 7a of the manual lever 3 in its upper connecting plate. A cylindrical member 6, which is freely supported at both ends and is connected to the pedal 2 via a rod 9, is connected to the mounting shaft 4 between a member 5 fixed to the mounting shaft 4 and one facing plate portion 7A of the fixed member 7. The fixing member 5 and the cylindrical member 6 are held loosely in an interposed state.
and engaging portions 5a, 6a that engage and interlock the two members 5, 6 when they are in contact with each other in the axial direction, and release the interlock when they are separated.
and a spring 10 that biases both members 5 and 6 in the direction of releasing the interlock.
and an operating screw device 8 which is capable of interlocking and unlinking the two members 5 and 6 with each other, and tightening and fixing the members 5 and 6 to the fixing member 7 in the interlocking state.

The engagement screw device 8 is formed at the end portion of the mounting shaft 4 through which one opposing plate portion 7A is inserted, and a tightening nut body 8c as a female thread member with an operating lever 8b is screwed into the male thread portion 8a. With,
Between the outer surface of the opposing plate portion 7A and the nut body 8c,
A disc spring 8d and a washer 8e as a friction mechanism are used to create a disengaged state when the nut body 8c is loosened, and when the nut body 8c is tightened, a reaction force is applied to the opposing plate portion 7A. By pulling and moving the mounting shaft 4 as a stand in the direction in which the cylindrical member 6 is sandwiched between the fixing member 5 and the opposing plate part 7A,
The mounting shaft 4 and the cylindrical member 6 are interlocked via the clutch mechanism 5b to create a state in which any speed change state can be maintained by operating the manual lever 3, and the mounting shaft 4 and the cylindrical member 6 are interlocked and , the disc spring 8d is released by tightening the nut body 8c in a state where one end of the cylindrical member 6 is in contact with the opposing plate portion 7A and movement of the mounting shaft 4 toward the male threaded portion 8a is impossible. By elastically deforming the nut body 8c and adjusting the tightening amount of the nut body 8c at this time, the frictional force between the cylindrical member 6 and the opposing plate part 7A is adjusted, and the mounting shaft 4 is attached to the opposing plate part. In contrast, it is fixed in a non-slidable manner and is configured to create a state in which the operation of both the manual operation lever 3 and the petal 2 is prevented.

In the figure, reference numeral 11 denotes a cam mechanism that biases the transmission 1 to a neutral position.

[Brief explanation of the drawing]

The drawings show an embodiment of the speed change operation device for a riding work vehicle according to the present invention, in which Fig. 1 is a side view of the entire riding work vehicle, Fig. 2 is an enlarged longitudinal side view of the main parts, and Fig. 3 is an enlarged longitudinal side view of the main parts. It is an enlarged vertical front view. DESCRIPTION OF SYMBOLS 1...Continuously variable transmission, 2...Petal for speed change operation, 3...Manual lever for speed change operation, 4...Mounting shaft, 5...Fixing member, 5b...Clutch mechanism, 6
...Cylinder member, 7...Fixing member, 8a...Male threaded portion, 8c...Femally threaded member, 8d...Friction mechanism.

Claims (1)

[Scope of utility model registration request] A mounting shaft 4 of a manual lever 3 for speed change operation, which has a male thread 8a formed on one end side, is pivoted to be movable back and forth in the axial direction with respect to a fixed member 7, and the male threaded portion 8a
is placed in a protruding position from the fixed member 7, and the female threaded member 8c is screwed onto the protruding end thereof, and is fixed to the mounting shaft 4 between the mounting portion of the manual gear shift operation lever 3 and the fixed member 7. Fix the member 5,
A cylindrical member 6 linked to the speed change operation pedal 2 of the continuously variable transmission control device 1 is loosely fitted onto the mounting shaft 4 between the fixed member 5 and the fixed member 7, and the fixed member 5
and the cylindrical member 6, the fixing member 5 and the cylindrical member 6
Spring 1 that biases in the direction of releasing the interlock with
0, and a clutch mechanism 5b that interlocks the fixing member 5 and the cylindrical member by movement of the mounting shaft 4 against the biasing force of the spring 10 as the female threaded member 8c spirals. Furthermore, the fixing member 5 is inserted between the female thread member 8c and the fixing member 7 as the female thread member 8c is screwed.
a friction mechanism 8 that brings one end of the cylindrical member 6 in an interlocking state into contact with the fixed member 7 and increases sliding resistance between the one end of the cylindrical member 6 and the fixed member 7;
A speed change operation device for a passenger work vehicle equipped with a.