JPS6245942Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field This invention is applicable to agricultural applications where the vehicle speed is changed by a gear shift lever linked to a hydraulic control lever, such as an HST type hydraulic transmission or a hydraulic clutch type transmission. On a tractor, the shift lever may move from the neutral position to forward or reverse speed due to an unconscious touch.
In order to prevent the agricultural tractor from starting, a locking metal fitting is provided on the speed change guide plate to fix the speed change lever and thereby improve safety.

(b) Prior Art A technique in which a gear shift lever and a gear shift guide plate are disposed below the steering handle is known.

For example, Japanese Patent Application Laid-Open No. 57-59129.

However, in agricultural tractors equipped with conventional hydraulic transmissions, there is no locking device for the gear shift lever, so if a hand or foot accidentally touches the gear when getting on or off, the gear shifts into forward or reverse, causing the operator to The train took off when I was not in my seat, leading to a serious accident.

(c) Problems to be solved by the invention This invention locks the gear shift lever in the neutral position by providing a locking metal fitting at the neutral position of the gear shift guide plate, thereby preventing accidents that may occur due to unconsciously touching the gear shifting operation. It is intended to prevent

(d) Means for solving the problem The purpose of the present invention is as described above. Next, the configuration for achieving the purpose will be explained.

A shift lever 4 of a transmission equipped with a hydraulic transmission is arranged below the steering handle 1 so as to be rotated back and forth, and a shift guide plate 6 of the steering handle 1 is placed between the steering handle 1 and the dart board 2. Located above and below, 3 forward speeds.
Guide grooves 6g and 6h for forward 2nd speed and 1st forward speed are provided on the front side of the speed change guide plate 6, and guide grooves 6 for reverse speed are provided on the front side of the speed change guide plate 6.
j is placed on the rear side, and the guide groove 6h for the first forward speed
A recess 6i for a neutral position configured one step lower is provided between the guide groove 6j for reverse speed and a biasing spring 2 that constantly biases the gear change lever 4 projecting laterally downward.
A lock fitting 5 is attached to the side surface of the speed change guide plate 6, and the lock fitting 5 is interposed therebetween and locks when the speed change lever 4 is fitted into the recess 6i.

(E) Embodiment The purpose and structure of the present invention are as described above. Next, the structure of the embodiment shown in the attached drawings will be explained.

FIG. 1 is a side view showing the structure of a gear shift operating device for an agricultural tractor, FIG. 2 is a rear view, FIG. 3 is a plan view of a gear lever guide, and FIG. 4 is a rear sectional view.

The agricultural tractor has an engine disposed in the front bonnet, a clutch housing 35 attached to the rear of the engine, and a transmission case 34 fixed to the rear of the clutch housing 35.

A main clutch device in the clutch housing 35 connects and disconnects the rotation of the engine, while a hydraulic clutch type transmission device in the transmission case 34 changes gears. The hydraulic directional control valve A selectively engages the hydraulic clutch of the hydraulic clutch type transmission.

By rotating the arm 31 protruding from the hydraulic directional control valve A back and forth, the spool within the hydraulic directional control valve A is moved back and forth to select a hydraulic clutch. This arm 31 can be changed in speed by fingertip operation using a speed change lever 4 device provided on the instrument panel 10 on the lower surface of the steering handle 1.

The interlocking configuration from the arm 31 side of the hydraulic directional control valve A to the gear shift lever 4 will be explained. Arm 3
A link 30 is pivotally connected to 1 by a pivot pin 36. The position of the pivot pin 36 can be adjusted using two nuts and one lock nut. Link 3
The front end of 0 is pivotally connected to an arm 29, and the arm 29 is fixed to the pivot shaft 28 and the arm 27.

The pivot shaft 28 is pivotally supported by a pivot device 32 fixedly installed in front of the case of the hydraulic directional control valve A.
The female screw body 2 of the turnbuckle device 8 is attached to the arm 27.
6 is pivotally connected to the other female threaded body 24 via the female threaded body of the turnbuckle device 8.

Adjustment of the turnbuckle device 8 is performed using the female screw body 2.
By loosening the lock nuts 38 and 37 of 6 and 24 and rotating the female threaded body, it is possible to accurately match the position of the speed change lever and the position of the spool of the hydraulic directional control valve.

A cover B covers the top of these link devices, and although these link devices are not visible from the outside, the turnbuckle device 8 can be easily adjusted by removing the cover B.

The female threaded body 24 is pivotally connected to the arm 17, and the arm 17 is fixed at right angles to the rotation shaft 9 in the rotation support cylinder 7.

A sliding groove 9a is provided at the tip of the rotation shaft 9,
The tip rotation pin 39 of the gear shift lever 4 is inserted into this groove 9a.
is inserted, and is prevented from coming off with a fixing body 40 from above. With this structure, the gear shift lever 4 can freely rotate up and down, but it can also rotate forward and backward with the rotation shaft 9.

A biasing spring 21 is interposed between the lever rod 4a of the gear shift lever 4 and the upper part of the rotating shaft 9, so that the gear shift lever 4 is always biased in the direction of being located on the neutral side of the gear shift guide groove. .

In FIGS. 1 and 2, 2 is a dart board, and a guide device for the gear shift lever 4 is fixedly installed on the instrument panel 10 of the dart board 2, and when the operator puts the thumb of his hand H on the steering handle 1, By placing all or some of the other index fingers, middle fingers, ring fingers, and little fingers on the gear shift lever 4, the gear can be changed by lightly operating only with the tips of the other fingers without taking off the steering handle 1.

In addition, as shown in FIGS. 2 and 3, the gear shift lever 4
The tip of the shift lever 4 is configured so that its tip extends outward from the outer periphery of the steering handle 1, and the rotation arc of the gear shift lever 4 draws an arc approximately concentric with the circle of the steering handle.

Further, as shown in the side view of FIG. 1, the steering wheel is adjusted so that the inclination angle of the steering handle 1 and the rotating direction of the gear shift lever 4, that is, the direction in which the guide groove of the gear shift guide plate 6 extends, are substantially aligned with the direction of the steering handle. The direction of rotation of the gear shift lever 4 is determined according to the rotation.

Also, the guide groove 6g of the speed change guide plate 6 in FIG.
As seen in the shapes of 6h and 6j, the 3rd forward speed and the 2nd speed are arranged in the uppermost single guide groove 6g,
A recess 6i for a neutral position is provided between the first forward speed and the reverse speed, which is recessed one step lower. Therefore, advance third
The vehicle does not shift from 2nd forward speed to reverse speed all at once, and conversely, it does not shift from reverse speed to 2nd or 3rd forward speed all at once. It is possible to switch between the first forward speed and the reverse speed at once without stopping the speed change lever at the neutral position. Further, the neutral position is provided with a recessed portion 6i which is one step lower, and the aforementioned biasing spring 21 and the lock fitting 5 are used in this recess to ensure that the neutral position is maintained.

In this way, the gear shift operating device is configured so that both the steering handle 1 and the gear shift lever 4 can be operated on the instrument panel 10 on the lower surface of the steering handle 1, so that the user can operate steering and gear shifting with one hand on the left. The right hand is used to operate the accelerator lever 31, direction indicator switch 18, warning buzzer switch 20, headlight switch 19, etc., as well as the hydraulic lever and other functions.
You can also operate the PTO gear shift lever, auxiliary gear shift lever, etc.

32 is a link that goes to the engine governor device, and 33 is a link that goes to the foot accelerator pedal. 13 is a fuel tank.

FIG. 5 is a plan view of the instrument panel 10, FIG. 6 is a back view, FIG. 7 is a side sectional view, and FIG. 8 is a rear sectional view of the part where the speed change guide plate and rotation support cylinder are integrated. Figure 9 is also a side view, Figure 10 is a plan view,
FIG. 11 is a plan view of the guide plate cover 3, and FIG.
13, 14, and 15 are a rear sectional view, a back view, a front side view, and a rear side view. 16, 17, and 18 are a plan view, a front view, and a side view of the lock fitting 5 of the gear shift lever 4.

First, the instrument panel 10 is fixed to the mounting surface of the dash board 2. On the instrument panel 10 is a speed tachometer 1.
1. Various warning lamps 21, direction indicator switch 8, warning buzzer switch 20, headlight switch 1
9 etc. are arranged, and the steering handle passes through the large hole 10a in the center. Then, the speed change operation device of the present invention is attached to the medium hole 10b and the small hole 10c.

The rotation support tube 7 shown in FIG. 8 is fitted into the inner hole 10b,
A bolt 16 is inserted into the small hole 10c through the hole 12b of the fixing fitting 12 of the speed change guide plate 6, and the instrument panel is fastened together. The speed change guide plate 6 is fixed to the instrument panel only by the bolts 16, and in addition, the lower end of the rotary support cylinder 7 is fixed by a presser metal fitting 42.

A guide groove 6g is carved on the side surface of the speed change guide plate 6, and the bottom surface is constituted by a fixing metal fitting 12, to which the rotation support tube 7 is also integrally fixed. The transmission guide plate 6 is provided with insertion holes 12a, 6a, 6c, and 6d for the insertion fixing pieces 3a, 3b, 3c, 3d, and 3e of the guide plate cover 3, and the guide plate cover 3 is made of synthetic resin. Therefore, insert fixing pieces 3a, 3b, 3c, 3d, 3e
It can be assembled and removed just by pushing it in.

In addition to the guide groove 6g, a medium hole 6d and small holes 6e and 6f are opened on the side surface of the speed change guide plate 6, and an elastic body 14 is inserted into the medium hole 6b as shown in FIG. 10 to lock the lock fitting 5. It serves as a retainer when released.

Also, the pivot pin 23 of the lock fitting 5 is inserted into the small hole 6f.
is inserted, and is biased and pivotally supported by a spring 22. Furthermore, a locking pin 15 is protruded from the small hole 6e of the speed change guide plate 6, as shown in FIG. 10, and the locking metal fitting 5 locks the speed change lever 4 in a locked state to the neutral position so as to prevent it from returning.

The lock fitting is provided with an inclined surface 5b as shown in FIG. 16, so when the handle 5a of the locking fitting is hooked with a fingertip and rotated in the locking direction, it rides on the inclined surface 5b and the locking pin 15 is automatically rotated. It locks in. To release the lock, the lock can be freely released by tilting the lock 5 against the spring 22 and removing it from the locking pin, and the lock is held by the elastic body 14.

(f) Effects of the invention Since the invention is constructed as described above, it has the following effects.

First, there is no longer any danger that an operator's body may come into contact with the gear shift lever when ascending or descending from the agricultural tractor, causing the shift lever to move from the neutral position to reverse or forward, causing the tractor to suddenly start.

Second, in the speed change guide plate 6, the three forward speeds and
The guide grooves for forward 2nd speed and forward 1st speed are located at the front,
For reverse speed, the guide groove is placed at the rear, and a recess for the neutral position is provided at a position one step lower between forward speed 1 and reverse speed, and the locking fitting is engaged only when the vehicle enters the recess. This, in combination with the presence of the biasing spring that always biases the gear shift lever 4 downward, makes it possible to create a fail-safe device that always guides the aircraft to the neutral stop side.

Thirdly, since these locking metal fittings are provided on the speed change guide plate, only a few parts are needed for the locking metal fittings.
The safety that exceeds the cost is achieved.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the structure of the gear shift operating device of an agricultural tractor, Figure 2 is a rear view, Figure 3 is a plan view of the gear lever guide, Figure 4 is a rear sectional view, and Figure 5 is the instrument panel. A plan view of the plate 10, FIG. 6 is a back view, FIG. 7 is a side sectional view, and FIG.
The figure is a rear sectional view of the part where the speed change guide plate and rotation support tube are integrated, Figure 9 is a side view, and Figure 10 is a side view.
The figure is also a plan view, and Figure 11 is the guide plate cover 3.
Plan view, Figure 12, Figure 13, Figure 14, Figure 1
Figure 5 is the same rear sectional view, back view, front side view,
The rear side view, FIGS. 16, 17, and 18 are a plan view, a front view, and a side view of the lock fitting 5 of the gear shift lever 4. 1... Steering handle, 2... Dash board, 4... Gear shift lever, 5... Lock metal fittings,
6... Speed change guide plate, 6g... Guide groove for 3rd forward speed and 2nd speed, 6h... Guide groove for 1st forward speed, 6i...
...Concave part for neutral position, 6j...Guide groove for reverse speed.

Claims (1)

[Scope of utility model registration request] A shift lever 4 of a transmission equipped with a hydraulic transmission is arranged below the steering handle 1 so as to be rotated back and forth, and a shift guide plate 6 of the steering handle 1 is placed between the steering handle 1 and the dart board 2. Located above and below, 3 forward speeds.
Guide grooves 6g and 6h for forward 2nd speed and 1st forward speed are provided on the front side of the speed change guide plate 6, and guide grooves 6 for reverse speed are provided on the front side of the speed change guide plate 6.
j is placed on the rear side, and the guide groove 6h for the first forward speed
A recess 6i for a neutral position configured one step lower is provided between the guide groove 6j for reverse speed and a biasing spring 2 that constantly biases the gear change lever 4 projecting laterally downward.
1 is interposed therebetween, and a locking fitting 5 is attached to the side surface of a speed change guide plate 6, which locks when the speed change lever 4 is fitted into a recess 6i.