JPH0236744Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves interlocking a pedal with a continuously variable transmission for driving that can freely switch forward and backward, and connecting the pedal to the pedal via an interlocking cam mechanism and a return spring. configured to return the traveling device to the traveling device drive stop position,
Furthermore, the present invention relates to a work vehicle provided with a safety device for starting the prime mover when the traveling device of the continuously variable transmission is stopped.

[Conventional technology]

Conventionally, in the above-mentioned work vehicle, the safety device is constructed by attaching an operating arm 12 that swings together with a shift operating shaft 11 of a continuously variable transmission 10 and interlocks with a rod 14, as shown in FIGS. 3 and 6. The pedal 13 is interlocked via the metal fitting 15, and the pedal 13 is depressed forward or backward to switch to forward F or reverse R, and the greater the amount of pedal depression, the higher the speed is steplessly shifted. A roller 17 attached to the support arm 16 is brought into contact with the F-shaped cam surface 12a at the lower end of the operating arm 12 by a spring 18, and is brought into contact with the F-shaped cam surface 12a of the operating arm 12 and the F-shaped cam surface 12a. A cam mechanism C consisting of a corresponding roller 17 and the spring 18 bias the pedal 13 back to the traveling device drive stop position N. Then, the V formed on the pedal 13
A contact switch 33 that comes into contact with the letter-shaped cam surface 13b
is connected in series with a key switch 21 to the power supply circuit of a starter 20 that starts the prime mover 1, and configured so that the prime mover can be started by the starter 20 only when the drive of the continuously variable transmission 10 is stopped. Prime mover 1 in running gear
This was to prevent the aircraft from unexpectedly flying out due to starting the aircraft. (I can't point to any literature.) [Problem that the invention attempts to solve] However, if you take your foot off the pedal 13, you can always reliably return the pedal 13 to the traveling gear drive stop position N and start the prime mover 1 immediately. So, spring 1
If the spring 8 is made strong, the pedal 13 operation becomes difficult.On the other hand, if the spring 18 is made weak so that the pedal 13 is easy to operate, the pedal 13 becomes difficult to operate.
3 is difficult to return to the traveling device driving stop position N, and it is difficult for the operator to find the traveling device driving stopping position N of the pedal 13 by feeling with the tip of the foot, which has the drawback that it takes time to start the driving unit 1.

In view of the above-mentioned circumstances, the purpose of the present invention is to provide a structure for preventing the accidental ejection of the aircraft when starting the prime mover, so that the pedals can be easily operated and the starting of the prime mover does not require much effort. be.

[Means to solve the problem]

The characteristic configuration of the present invention is that, in the above-mentioned work vehicle, a safety device for starting the prime mover when the drive of the continuously variable transmission for traveling is in a state where the drive of the traveling gear is stopped, causes a pedal linked to the continuously variable transmission to drive the traveling gear. A device that locks the engine at a stop position, and a linkage device that automatically puts the lock device into operation in conjunction with a stop operation of an engine start switch of the prime mover, further comprising an engaging member constituting the lock device; A guide surface is formed on either one of the engaged members, and the position of the pedal can be adjusted to the traveling device drive stop position when the locking device is locked, and its effects are as follows. It is as follows.

[Effect]

In other words, when the prime mover is stopped, the pedal automatically locks to the traveling gear drive stop position and does not move, and even if the operator carelessly places his foot on the pedal when starting the prime mover, The driving state is prevented from appearing.

Moreover, the structure that corrects the position of the pedal to the travel gear drive stop position only acts on the pedal when it is locked, so even if a large force is applied to the pedal in order to reliably correct the position, the pedal operation becomes heavy. That's not the case at all.

[Effect of idea]

As a result, it is possible to reliably prevent the aircraft from jumping out unexpectedly when the prime mover is started, and it also prevents the pedal operation from becoming heavy and the time required to start the prime mover, resulting in overall safety. We were able to provide a work vehicle that was excellent in both performance and operability.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in FIG. 2, a vehicle body formed by connecting a prime mover 1, a main clutch housing 2, and a transmission case 3 in the front and back has a pair of left and right rear driving wheels 4 and a pair of operable left and right front driving wheels 5. are each supported on a shaft. A boarding and operating section 6, a steering handle 7, etc. are provided on the upper part of the vehicle body, and a lift arm 8 that can be raised and lowered to suspend various working devices and a lift arm 8 for transmitting power to the working devices is provided at the rear of the vehicle body.
It is equipped with a PTO shaft 9, etc., and constitutes a riding tractor for carrying out various agricultural works.

As shown in FIG. 3, a continuously variable transmission 10 for traveling is provided in the transmission case 3, and an operating arm 12 that swings integrally around the axis P of the operating shaft 11 of the transmission 10 is attached to the operating arm 12 for operation. Arm 12 and fulcrum
The pedal 13, which is attached to the transmission case 3 so as to be able to swing freely around Q ₁ , is linked by a push/pull rod 14 and an interlocking metal fitting 15, so that by depressing the pedal 13 forward or backward, the vehicle can move forward F or backward. It is configured such that the gear is switched to R, and the larger the amount of depression, the higher the speed. The roller 17, which is attached to the transmission 10 so as to be able to swing around the fulcrum _Q2 via the support arm 16, is pushed against the inverted V-shaped cam surface 12a formed at the lower end of the operating arm 12 by the biasing force of the spring 18. the operating arm 12
A cam mechanism C consisting of an F-shaped cam surface 12a and a roller 17 in contact with the F-shaped cam surface 12a, and the spring 18 bias the pedal 13 back to the traveling device drive stop position N. be.

As shown in FIG. 4, a solenoid switch 19 operates the stop lever of the prime mover 1 in the energized state.
A key switch 21 for starting the engine provided in the driving unit 6 is interposed in the power circuits a and b for the starter 20 that starts the prime mover 1, and the prime mover 1 can be stopped and started by switching the key switch 21. It is configured to do so. As shown in FIGS. 4 and 5, a sensor switch 22 is attached to the driver's seat 6a, which becomes energized when the driver is not seated, and the switch 22 is connected to the power supply circuit a of the solenoid switch 19 by a key switch. 21 in parallel, and is configured to stop the prime mover 1 and stop the aircraft from moving if the pilot falls from the seat 6a. Further, a sensor switch 24 that is energized only when the clutch is disengaged is attached to the clutch pedal 23, and a sensor switch 25 that is energized when the driver is seated is attached to the driver's seat 6a. is connected in series with the key switch 21 to the power supply circuit b of the starter 20, and only when the operator is seated and depresses the clutch pedal 23 to disengage the clutch.
It is configured so that the prime mover 1 can be started by a key switch 21.

As shown in FIG. 1, a locking device L fixes the pedal 13 at the traveling device drive stop position N by inserting a pin 26 as an engaging member into a hole 13a as an engaged member formed in the pedal 13. is attached to the transmission case 3, and the pin 26, which is biased toward the protruding side by a spring 27, is latched in a retracted state by a latching piece 28. Then, the solenoid switch 29 removes the latch piece 28 and causes the pin 26 to protrude.
is connected in parallel with a solenoid switch 19 that operates the stop lever of the prime mover 1, as shown in FIG. In other words, in conjunction with the stoppage of the prime mover due to the operation of the key switch 21 or due to a fall of the operator, etc., the locking device L is activated to fix the pedal 13 in the traveling gear drive stop state, and when the prime mover 1 is started again. The system is configured so that the traveling device driving state does not appear during operation, and after the motor 1 is started, the lock is manually released by grasping the handle 30, and then the traveling speed change operation is performed.

Further, as shown in Fig. 4, the power circuit a of both solenoid switches 19, 29 is energized only for a certain period of time (for example, 5 to 7 seconds required to stop the prime mover). The timer 31 and the key switch 21 or the sensor switch 22 attached to the seat 6a remain energized for a certain period of time (for example, if the sensor switch becomes energized temporarily due to vibration of the vehicle body, the vehicle will not stop running). A timer 32 is connected in series to keep both solenoid switches 19 and 29 energized only when the operation is continued (up to 7 seconds).

Furthermore, as shown in FIG. 1, the pin 26 is formed into a tapered shape, and the hole 13a of the pedal 13 is formed so that its opening becomes larger toward the transmission case 3.
By the action of the engaging portion K formed by the inclined surface S serving as the guide surface of the pedal 13, the position of the pedal 13 can be corrected to the traveling device drive stop position N as the pedal 13 is locked. That is, the spring 18 for restoring the pedal 13 to the traveling device drive stop position N shown in FIG. When the pedal 13 is locked due to the locking of the pedal 13, a strong force is applied to reliably restore the pedal 13 to the traveling device drive stop position N.

[Another example]

Next, another example will be described.

The lock device L can be modified in its shape, mounting structure, etc. as appropriate, and the lock pin 26 as an engaging member is provided on the pedal 13 side, and the hole 13a as an engaged member is provided in the side wall of the mission case 3. Good too. The means for interlocking the locking device L with the stop operation of the prime mover 1 can be replaced by the solenoid switch 29 and may include various electrical or mechanical means, and these are referred to as a linking device 29. Further, the locking device L may be automatically brought into the unlocked state using a timer or the like. The guide surface S for correcting the position of the pedal 13 to the travel device drive stop position N may be formed only on either the lock pin 26 or the hole 13a.

Furthermore, a sensor switch is attached to the locking device L, which becomes energized only when the locking device L is activated, and the sensor switch is connected in series to the power supply circuit b of the starter 20 of the prime mover 1. It may be arranged to prevent the aircraft from unexpectedly flying out.

The present invention targets working vehicles for various uses such as construction and agricultural use, and includes specific configurations of the working vehicle, such as interlocking means between the continuously variable transmission 10 and pedal 13, or starting means for the prime mover 1. can be changed as appropriate.

[Brief explanation of drawings]

Figures 1 to 5 show an embodiment of the working vehicle according to the present invention, in which Figure 1 is a partially cutaway plan view, Figure 2 is an overall side view of the tractor, and Figure 3 is a partially cutaway side view. 4 is a power supply circuit diagram for starting and stopping the prime mover, and FIG. 5 is a side view of the driver's seat.
FIG. 6 is a side view corresponding to FIG. 3 showing a conventional example. 1... Prime mover, 10... Continuously variable transmission, 13...
...Pedal, 13a...Engaged member, 18...Return spring, 21...Engine start switch, 2
6... Engagement member, C... Cam mechanism, S... Guide surface, N... Traveling device drive stop position, L... Lock device, 29... Linking device.

Claims (1)

[Scope of utility model registration request] A pedal 13 is linked to a continuously variable transmission device 10 for driving that can freely switch forward and backward, and is configured to return the pedal 13 to a traveling device drive stop position N via a cam mechanism C and a return spring 18 linked to the pedal 13. Further, the work vehicle is provided with a safety device for starting the prime mover 1 when the drive of the continuously variable transmission device 10 is stopped, and the safety device moves the pedal 13 to a drive stop position N of the drive device. and a linking device 2 that automatically puts the locking device L into operation in conjunction with the stop operation of the engine start switch 21 of the prime mover 1.
9, furthermore, the pedal 13 is connected to one of the engaging member 26 and the engaged member 13a constituting the locking device L to stop the driving of the traveling device when the locking device L is locked. A work vehicle in which a guide surface S whose position can be corrected is formed at a position N.