JPH0657498B2 - Operation structure for traveling of work vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention provides a transmission-side member that is interlocked with an operating portion of a continuously variable transmission for traveling, is swingable, and urges toward a deceleration side. A stopper that contacts the transmission side member to maintain the traveling continuously variable transmission at a set speed state, and another axis that is parallel or substantially parallel to the swing axis of the transmission side member. The present invention relates to an operating structure for traveling of a work vehicle in which a speed control lever for swinging and adjusting the traveling continuously variable transmission to increase / decelerate the traveling speed and changing a maintenance set speed by the stopper is swingably provided.

[Conventional technology]

Conventionally, as the above-mentioned work vehicle, for example, there is one disclosed in Japanese Utility Model Laid-Open No. 60-96183. That is, as the speed control lever is operated toward the high speed side, the stopper acts on the high speed device side member by shifting the position toward the free end side of the high speed device side member and the swinging shaft core of the transmission device side member and the stopper There is a positional relationship with the shaft core. That is, the swing angle at which the transmission-side member is operated by swinging the speed control lever by a unit angle becomes smaller as the speed control lever is operated toward the higher speed side.

[Problems to be Solved by the Invention]

In the conventional case, if the entire stroke of the speed control lever is to be kept small, the operable swing angle of the transmission side member will also be small, and the actual shift range that the transmission itself has can be changed. It was smaller than the range or smaller than the desired range.

The object of the present invention is to reduce the total stroke of the speed control lever to a small value, regardless of the setting of the positional relationship between the swing shaft core of the transmission side member and the swing shaft core of the stopper. It is to be able to increase the range that can actually be changed.

[Means for Solving the Problems]

According to a characteristic configuration of the present invention, in the operating structure for traveling of the work vehicle described above, the swing angle at which the transmission side member is operated by swinging the speed control lever at a unit angle is set so that the speed control lever moves to a high speed side. At least one of the stopper contact surface of the speed change device side member and the acting surface of the stopper is formed on the cam surface which is enlarged as much as possible. The action and effect are as follows.

[Action]

For convenience of arrangement design of various devices, the stopper is displaced to the free end side with respect to the transmission side member due to the speed increasing operation. Even if the stopper is used as the swing shaft core, the swing angle of the transmission side member accompanying the swing of the stopper may be the same as the stopper swing angle regardless of the displacement of the stopper with respect to the shift device side member. The cam surface can be made larger than the conventional one, such as being larger than the swing angle. Further, the stopper is displaced toward the base end side of the transmission side member due to the speed increasing operation, and the speed change range by the unit stroke operation of the speed control lever becomes large on the high speed side. Even with the core arrangement relationship, the degree to which the swing angle of the transmission-side member accompanying the swing of the stopper becomes larger than the stopper swing angle is greater than that due to the shaft center arrangement relationship. It is possible by the cam surface.

〔The invention's effect〕

The cam surface allows the rocking stroke of the speed control lever to be kept small, allowing the lever to be placed in a relatively limited space, and yet, for that reason, the transmission range provided by the transmission itself It has been possible to secure a wide traveling speed range in which gears can be actually changed, such as a changeover operation over the whole or a desired range, so that gear shifting can be advantageously performed.

〔Example〕

 Next, examples will be shown.

As shown in FIG. 4, the lawn mowing device (1) is mounted between the front and rear wheels of the wheel-type traveling vehicle so that it can be moved up and down, and the driving force is transmitted from the traveling vehicle to the lawn mowing device (1). ,
A riding lawn mower is constructed.

The output of the engine (E) is transmitted to the rear wheel mission (3) via the hydraulic traveling continuously variable transmission (2) that can switch between the forward side and the reverse side across the neutral state. Then, the continuously variable transmission (2) is operated by the traveling operation structure shown in FIG. 1 and FIG.

That is, the rotary pedal (2a) of the continuously variable transmission (2) is connected to the speed change pedal via the swing link (4) and the push-pull rod (5).
(6) is interlocked, and when the speed change pedal (6) is operated by depressing the forward operation part (6a), the operation part (2a) is rotated forward, and the speed change pedal (6) On the reverse side
The operation part (2a) rotates more toward the reverse side when (6b) is depressed, and the operation part (2a) becomes larger as the depression operation stroke of the speed change pedal (6) is increased. It is designed to be on the high speed side. Then, the roller portion (7a) of the arm (7) pivotally attached to the case of the rear wheel mission (3) so as to swing around the shaft center (P ₁ ) is connected to the swing link (4) by the spring (8). ) Is attached to the cam surface (4a) and biased, and a swinging link for this contact bias and the shape of the cam surface (4a)
When the gearshift pedal (6) is released, the spring (8) is configured so that (4) is biased to the neutral state.
The shift pedal (6) and the operating portion (2a) are automatically returned to the neutral position due to the biasing force of the continuously variable transmission (2) and the self-restoring force of the continuously variable transmission (2).

A stopper made of a round rod for receiving and supporting the swinging link (4) at the forward side position so as not to return to the neutral state regardless of the biasing force of the spring (8) and the restoring force of the continuously variable transmission itself to the neutral state. (9) is attached to the fuselage side support member (11) via the attachment plate (10). Mounting plate (10) is a swing link
Another axis parallel or almost parallel to the swing axis (P ₂ ) of (4)
The boss (1) of the support member (11) is rotated so that it rotates around (P ₃ ).
_1a ) is configured to be fixed to the support member (11) mainly by the friction type lock mechanism (A) when it is fitted on the outer side of the round bar forming the stopper (9). By swinging the speed control lever (12) created in step ₃ around the axis (P ₃ ), the stopper (9) is swing-adjusted around the axis (P ₃ ) and the swing link (4) is pushed and oscillated to the high speed side to continuously variable transmission
The stopper (9) is set so that the speed change operation of (2) or the swing link (4) is allowed to move to the neutral side to decelerate the continuously variable transmission (2). The continuously variable transmission (2) is maintained at the set speed state determined by the position of the swing link (4) by being fixed to the adjusted position by the lock mechanism (A) and receiving and supporting the swing link (4). Is done.

In other words, during work, the stopper (9) is rocked and adjusted by the rocking operation of the speed control lever (12) to accelerate and decelerate the continuously variable transmission (2), and at the same time the desired set speed is maintained by the stopper (9). Continuously variable transmission by changing and adjusting to speed (2)
The vehicle can travel at a desired constant speed without any manual operation for maintaining the vehicle in a forward transmission state at a desired speed. Then, when traveling while performing a speed change operation with the speed change pedal (6) or when traveling in reverse, the speed control lever (12) is located on the side opposite to the forward side with respect to the neutral position (N). Operate to the position (OFF), position the stopper (9) out of the operating range of the swing link (4) so as not to obstruct the gear shifting operation, and at this point friction lock mechanism.
It is kept by (A).

The stopper contact surface (4b) where the stopper (9) of the rocking link (4) acts is formed on the arcuate cam surface as shown in Fig. 1, and the shaft cores (P ₂ ) and (P ₃ ) Regardless of the positional relationship,
From the neutral position (N) of the speed governor (12) to the forward maximum speed position (Fma
It is configured so that the speed change range that can be operated by the speed control lever (12) is large relative to the operation stroke up to x).
That is, because of the cam surface shape of the stopper contact surface (4b), as shown in FIG. 3, the rocking link (4) is operated by rocking the speed adjusting lever (12) at a unit angle (α). Increase the swing angle (β) as the speed adjustment lever (12) is on the high speed side,
When the speed control lever (12) is operated toward the high speed side, even if the stopper (9) shifts to the free end side of the swing link (4) due to the swing of the speed control lever (12), it swings. The actual swing angle of the link (4) is made larger than the swing angle of the speed control lever (12).

In the lock mechanism (A), the mounting plate (10), the pair of friction plates (13), (13) and the pressing member (14) respectively located on both sides of the mounting plate (10) are attached to the lock spring (15). The mounting plate (10) is pushed by pressing it toward the support member (11) by the elastic restoring force.
A frictional resistance is provided so that the swinging link (4) is not swung by the neutral restoring force. When the traveling brake (16) provided in the rear wheel mission (3) is braked, it is integrated with the rotary shaft (17) for interlocking the traveling brake (16) and the brake pedal (not shown). The swinging arm (18) attached so as to be rotatable contacts the lock spring (15) and the operation arm (20) of the support shaft (19) of the pressing tool (14) to rotate the support shaft (19). The lock release cam (22), which is attached to the support shaft (19) by the mounting pin (21) so as to rotate integrally, is the spring operation member (23) which is slidably attached to the support shaft (19). Through the lock spring (1
5) is configured to be compressed and deformed to an unlocked state. That is, when the driving brake (16) is braked, it automatically becomes unlocked and the stopper (9)
The maintenance of the traveling speed due to is canceled.

[Another embodiment]

As a member that actuates the stopper (9), a continuously variable transmission
Instead of using the swing link (4) for interlocking the (2) and the speed change pedal (6), a swing member dedicated to the swing link (4) may be provided.
Therefore, the swing link (4) is referred to as a transmission-side member (4) that is interlocked with the operating portion of the continuously variable transmission.

Stopper (9) as the governor lever (12) swings to the high speed side
If the stopper swing shaft core (P ₃ ) and the shift member side member swing shaft core (P ₂ ) are arranged and set so that the stopper is displaced toward the transmission shaft side member, The invention is applicable.
In this case, in addition to shortening the stroke of the speed control lever due to the displacement, it is possible to further shorten the stopper contact surface (4b) by the shape of the cam surface.

In addition to forming the stopper contact surface of the transmission side member on the cam surface, the working surface of the stopper may be formed on the cam surface, or only the working surface of the stopper may be formed on the cam surface. You may.

The present invention is applicable to various work vehicles such as agricultural tractors, combine harvesters, rice transplanters, and transport vehicles as well as lawnmowers.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

The drawings show an embodiment of an operating structure for traveling of a work vehicle according to the present invention. FIG. 1 is a side view of a transmission speed-control operating portion, and FIG. 2 is a partial cutaway of the transmission speed-control operating portion. FIG. 4 is a front view, FIG. 3 is an explanatory view of a stopper working state, and FIG. 4 is a side view of the entire lawn mower. (2) …… Continuously variable transmission for traveling, (4) …… Transmission gear member,
(4b) …… Stopper contact surface, (9) …… Stopper, (12)
…… Governor, (P ₂ ), (P ₃ ) …… Axis core.

Claims (1)

[Claims] 1. A transmission side member (4) interlocking with an operating portion (2a) of a traveling continuously variable transmission (2) is swingably provided and urged toward a deceleration side, and the transmission side member is provided. A stopper (9) that contacts the (4) and maintains the traveling continuously variable transmission (2) at a set speed state, and this stopper (9) is a swing shaft of the transmission side member (4). The above-mentioned continuously variable transmission for traveling by adjusting the swing around another axis (P ₃ ) parallel or almost parallel to the core (P ₂ ).
(2) An operating structure for traveling of a work vehicle provided with a speed control lever (12) for changing the maintenance set speed by the stopper (9) while accelerating and decelerating the speed control lever (9). 1
By the swinging of the unit angle (α) in 2), the transmission side member
(4) The swing angle (β) that is operated is increased as the speed control lever (12) becomes higher in speed.
Stopper contact surface (4b) of (4) and the stopper (9)
An operating structure for traveling of a work vehicle in which at least one of the working surfaces of the work vehicle is formed.