JPS6238419Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speed change operation section for a working vehicle that is provided with a pedal that allows forward and forward switching and speed change operations.

Conventionally, in the above-mentioned speed change operation section, a safety stopper operation tool is attached to the pedal to prevent the pedal from being erroneously depressed from the neutral position to the reverse position.
The system was configured so that the stopper was operated with the foot placed on the pedal, but the pedal and operating tool had different configurations, making it difficult to perform the two operations in a timely manner with one foot.For example, the stopper could not be completely released. There are operational problems such as pressing the pedal to the reverse position when the pedal is not in the neutral position or the forward position. There was still room for improvement in terms of safety, as it was sometimes easy to release the stopper by mistake.

In view of the above-mentioned circumstances, the purpose of the present invention is to make it possible to easily operate the stopper in conjunction with the pedal at an appropriate timing through reasonable improvements, and to ensure that erroneous operation of the stopper can be prevented. , which also improves overall operability.

The characteristic configuration of the shift operation unit of the present invention includes a stopper that prevents the pedal from being depressed from the neutral position to the reverse position in the above-mentioned work vehicle, a biasing mechanism that maintains the stopper in the operating position, and a biasing mechanism for the same. A manual operating device is provided between the pedal and the stopper for displacing the stopper to the release position against the biasing mechanism. A cam mechanism is provided for displacing the stopper to the release position, and its effects are as follows.

In other words, by configuring the operating tool for displacing the stopper to the deactivating position against the biasing mechanism for maintaining the operating position as a manual operating tool, the pedal and the stopper can be operated separately with the foot and hand. The stopper can be operated with the foot placed on the pedal as in the conventional configuration, and the stopper can be easily operated in conjunction with the pedal at an appropriate time, and the stopper can be operated manually. Therefore, it has become possible to reliably prevent the stopper from being erroneously released with the foot when the pedal is depressed in the neutral or forward position. Furthermore, by providing a cam mechanism that automatically displaces the stopper to the release position against the biasing mechanism as the pedal is depressed from the reverse position to the neutral position, the stopper release operation using the operating tool is not required. It is possible to operate the pedal by pressing it to the neutral position side without any movement, and overall the shift operation of the work vehicle is excellent in both the operability of the stopper and the operability of the pedal, and is even better in terms of safety. We have now been able to provide a portion of the

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

As shown in FIGS. 1 and 2, a driving unit 3 covered by a bonnet is mounted on the front part of a vehicle body frame 2 that supports a pair of left and right front propulsion wheels 1 for steering, and a pair of left and right rear propulsion wheels 4 is mounted. A transmission case 5 equipped with this is connected to the rear end of the vehicle body frame 2, and
A boarding operation section 6 is provided at the center of the left and right sides of the fuselage. The power from the driving unit 3 is inputted via a transmission shaft 8 to a continuously variable transmission 7 which is directly connected to the front part of the transmission case 5 and can freely switch between forward and backward movement. The gear change output extracted from the tractor is transmitted directly to the rear wheels 4 and to the front wheels 1 via the propeller shaft 9, respectively, and an agricultural tractor is constructed as an example of a working vehicle. .

To configure the operation structure for the continuously variable transmission 7, as shown in FIG. The operation part of the continuously variable transmission 7 is mounted on the pedal swing support shaft 11 which is provided on the step 6a of the driving part 6 in a biased state and rotates integrally with the pedal 10.
Interlocking connection so that the forward speed increases as the pedal 10 is depressed toward the front side, and the reverse speed increases as the pedal 10 is depressed toward the rear side, in a state in which forward and backward switching is performed by switching forward and backward. It has been done. Then, the pedal 10 is moved from its neutral position N to its reverse position R.
It is equipped with a backward movement control device 12 that prevents the user from stepping on the reverse movement position R, and is configured to prevent the aircraft from moving backwards due to an erroneous depression operation toward the backward movement position R side.

To configure the reverse operation restraining device 12, an abutting member 13 is fixed to the rear end of the pedal 10, and the abutting action of the abutting member 13 on the lower surface causes the pedal 10 to move from the neutral position N to the reverse position R. At step 6, the stopper 14 that prevents stepping is
It is fixedly attached to a manual operation lever 15 mounted near a so that it can be freely swung back and forth. A spring 16 attached to the pivot portion of the lever 15 causes the lever 1 to
Adjustment bolt 1 that constantly elastically urges the lever 5 forward and prevents the lever 15 from swinging forward at a predetermined swing position against the spring 15.
7 is provided, and the stopper 14 is always located on the movement trajectory of the abutment member 13 through cooperation with the spring 16 and adjuster bolt 17, thereby maintaining the backward movement restraint state of the pedal 10 and preventing the pedal 10 from moving backward. As the pedal is depressed from position R to neutral position N, the stopper 14 is moved together with the lever 15 by the spring 1 due to the contact action with the lower surface of the stopper 14.
The abutment member 3 is formed with an abutment cam surface 13a that allows the abutment member 13 to pass upward by temporarily retracting and swinging to the rear side against the movement of the abutment member 3. When the pedal 10 is depressed, the lever 15 is manually operated to allow the pedal 10 to be depressed, and when the pedal 10 is depressed from the reverse position R to the neutral position N, the pedal 10 can be depressed without manual operation on the lever 15. In this way, it is configured to improve the operability of the pedals 10 while ensuring a check on reverse operation.

Furthermore, by configuring the manual release operating device of the stopper 14 with the manual lever 15, the pedal 10 and the stopper 14 can be operated separately with the foot and hand, and each operation can be easily performed at the appropriate timing. and the neutral/forward position N of the pedal 10,
It is constructed to reliably prevent the stopper 14 from being erroneously released during the depression operation in F, thereby further improving safety.

The specific shape of the stopper 14 and the structure for preventing the pedal from being depressed can be modified in various ways, and the biasing structure for maintaining the stopper 14 in the operating position may be modified by using a weight instead of a spring. Various improvements are possible, such as using a formula biasing structure or a fluid pressure biasing structure, and these biasing structures are collectively referred to as the biasing mechanism 16.

In addition, various types of manual operating tools 15 can be used instead of the lever as the operating tool for manually operating the stopper 14 to the release position against the biasing mechanism 16. Various improvements can be made to the specific interlocking structure between the tool 15 and the stopper 14.

Furthermore, the pedal 10 is moved from the reverse position R to the neutral position N.
As the specific cam structure for automatically displacing the stopper 14 to the deactivation position against the biasing mechanism 16 as the user depresses the button, it is possible to apply various conventionally known cam structures. are collectively referred to as a cam mechanism 13a.

The present invention is directed to a pedal-type gear shift operation unit in work vehicles for various uses such as agricultural and construction use.

[Brief explanation of the drawing]

The drawings show an embodiment of a speed change operation section for a working vehicle according to the present invention, and FIG. 1 is an overall side view of the tractor, and FIG. 2 is an enlarged side view showing a speed change pedal structure. 10...Pedal, 13a...Cam mechanism, 14...
...stopper, 15...manual operating tool, 16...biasing mechanism, N...neutral position, R...reverse position.

Claims (1)

[Scope of utility model registration request] In a work vehicle equipped with a pedal 10 that can freely switch between forward and backward directions and change gears, a stopper 14 that prevents the pedal 10 from being depressed from a neutral position N to a reverse position R, and a biasing mechanism 16 that maintains the stopper 14 in an operating position. , and a manual operation tool 15 for displacing the stopper 14 to the deactivation position against the biasing mechanism 16 is provided between the pedal 10 and the stopper 14 to move the pedal 10 from the reverse position R to the neutral position N. A shift operation section for a working vehicle, which is provided with a cam mechanism 13a that displaces the stopper 14 to an action release position against the biasing mechanism 16 when the driver is depressed.