JPS5941176Y2 - Parking bracket device for four-wheel drive tractor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a parking bracket device for a four-wheel drive tractor.

Conventionally, brackets and fulcrums were provided independently for the PTO clutch, four-wheel switching lever, and parking brake, which resulted in an increase in the number of parts and a complicated structure.

The present invention improves the arrangement of the levers by concentrating the above levers on a single bracket that also serves as a retaining plate for the PTO clutch pin, thereby eliminating the need for extra brackets. .

In FIG. 1 showing the left side of the agricultural tractor (arrow F points to the front), the parking bracket 10 is a thick rectangular member that is fastened to the side wall of the transmission case 8 with three bolts 25, and is connected to the PTO (to be described later). It supports the clutch pin 7 and the four-wheel switching lever pin 27, and the support bracket 29 for the parking brake lever 28 is attached to the tip of the bolt 3.
It is fixed at 0.

The parking brake lever 28 is supported by a bracket 29 via a pin 30', and a pin 31 is provided at the intermediate portion.
A brake rod 32 is connected to the ratchet pawl 33 supported by the pin 31, and the ratchet pawl 33, which is supported by the pin 31, receives the elasticity of a spring (not shown) and normally engages the ratchet 3 on the support bracket 29 side.
4, and by pressing the bush button 35, the ratchet pawl 33 is engaged with the ratchet 3 against the elasticity of the spring.
It can be removed from 4.

The lower end of the brake rod 32 is connected to the arm 3 via a pin 36.
The hole 38 at the base end of the arm 37 is rotatably supported on the brake pedal shaft 39, and the pin 40 fixed to the upper edge of the arm 37 is connected to the tip of the arm 37. It is in contact with the rear edge of 41.

The brake pedal shaft 39 is rotatably supported by a support bearing 42 fixed to the bottom surface of the transmission case 8.
One arm 41 is fixed to each of the left and right ends of the transmission case 8, and the tip of each arm 41 is connected to a brake cam shaft 47 via a pin 43, a brake rod 44, a pin 45, and an arm 46. .

The brake camshaft 47 is supported by a brake cover 49 attached to a rear axle case 48.

A brake pedal 50 is fixed to the right end of the brake pedal shaft 39, and the tread surface 51 normally projects above the step 52 due to the elasticity of a return spring 53 stretched between it and the step 52.

54 is a stopper.

When the brake pedal tread surface 51 is returned and depressed in the direction of arrow A against the elasticity of the spring 53, the arm 41 integrated with the brake pedal 50 rotates in the direction of arrow B via the brake pedal shaft 39, leaving the pin 40 behind. The movement of the arm 41 is transmitted to the arm 46 via the brake rod 44, and the brake camshaft 47 rotates in the direction of arrow C, thereby applying the brake.

When parking, pull the parking brake lever 28 to pin 3.
When the lever 28 is pulled in the direction of the arrow B with 0 as the fulcrum, the movement of the lever 28 is transmitted to the arm 37 via the brake rod 32, and the pin 40 integrated with the arm 37 drives the arm 41 in the direction of the arrow B, causing the brake pedal 50 to be depressed. In the same way as in the case where the brake is pressed, the brake is applied, the ratchet pawl 33 engages with the ratchet 34, and the braking state is maintained.

To release the parking brake, press Button 3.
5 to remove the ratchet pawl 33 from the ratchet 34 and return the lever 28 in the opposite direction.

1 in Figure 2 is the PTO clutch lever with grip 2 on the upper end.
The base end 3 is welded to a boss tube 4, and the boss tube 4 has a thick rectangular plate-shaped bracket 5 integrally welded on the opposite side (lower side) of the base end 3.

The boss cylinder 4 is fixed to the tip of a PTO clutch pin 7 via a pin 6, and the PTO clutch pin 7 is rotatably supported in a bearing hole 9 of a transmission case 8, and the PTO clutch is mounted inside the case 8. It has an on/off shift fork (not shown).

The parking bracket 10 has a hole 11 that fits onto the clutch pin 7 up to the flange 12 and functions to prevent the clutch pin 7 from being pulled out. 13 is a stopper pin that is in a position parallel to the clutch pin 7. It is fixed to the lower end of the parking bracket 10, and its tip passes through a rectangular four section 15 provided at the tip of the bracket 5, as shown in FIG.

As is clear from FIG. 3, the recess 15 and the stopper pin 13 are arranged so that the bracket 5 can rotate within an angle α about the clutch pin 7 with respect to the fixed stopper pin 13.
A gap (a gap in the circumferential direction around the clutch pin 7) is provided between the stopper pin 13 and the leaf spring 16.
It is located on one side of the recess 15 due to the action of.

Both ends of the leaf spring 16 come into contact with both ends of the bracket 5 via shims 17 shaped like washers with holes, and are each fastened to the tip of the bracket 5 by bolts 18, with the part facing the fourth part 15 inside the recess 15. It extends in an arc shape, and the tip of the arc 1
One of the hem portions 16b and 16c on both sides of the bracket 6a is in pressure contact with the stopper pin 13 to elastically hold the bracket 5 in the clutch-on position shown by the solid line.

19 is a screw hole provided at the tip of the bracket 5, and 20 is a spring washer.

For example, when the clutch lever 1 is in the ON position indicated by the solid line as shown in FIG. 3, the PTO clutch is in a connected state and rotational force can be supplied to the working machine.

When the clutch lever 1 is operated in the direction of the arrow F in FIG. 3 to the off position shown by the two-dot chain line, the arc tip 16a of the leaf spring 16 passes through the stopper pin 13 while being deformed, and the hem 16b The bracket 5 is elastically pressed against the stopper pin 13 to maintain the bracket 5 in the off position.

That is, it exhibits a detent (detect) function.

To increase the detection load, one bolt 18 is completely removed from the screw hole 19, the number of shims 17 is reduced, and the bolt 18 is screwed into the screw hole 19 again.

If you want to increase the detect load at the on position, use the third
The number of shims 17 on the right side of the figure may be reduced, and the number of shims 17 on the left side may be reduced to increase the detection load at the off position.

When used in applications where there is little vibration, the detect load can be reduced by increasing the thickness or number of shims 17, and in that case, the clutch lever operation load is significantly reduced.

As shown in FIG. 2, the four-wheel switching lever pin 27 is fixed to the bracket 10 by having a male threaded portion 56 at the tip pass through a hole in the parking bracket 10 and screwing a nut 57 therein. A substantially triangular flange 59 is fixed at one apex of the movably supported boss cylinder 58, and a four-wheel switching lever 6 is attached to one of the remaining two apexes.
The base end of the rod 61 is connected to the other vertex, and the bent portion 62 of the lower end of the rod 61 is connected to the arm 64 fixed to the four-wheel switching clutch pin 63. are doing.

65 is a boss cylinder to which the arm 64 is fixed, which fits into the pin 63 and is prevented from being removed by the pin 66.

The four-wheel switching clutch pin 63 is provided with a shift fork (not shown) inside the transmission case 8, and can drive a sliding gear of a front wheel drive PTO device provided at the bottom of the transmission case.

For example, when the grip 67 of the four-wheel switching lever 60 is pulled upward (in the direction of arrow E), the four-wheel switching clutch is engaged and the tractor becomes a four-wheel drive system.

Conversely, when the grip 67 is operated downward, the four-wheel switching clutch is disengaged and the rear two-wheel drive system is established.

As explained above, in the present invention, a plate-shaped parking bracket 10 that also serves as a retaining plate that engages with the outer surface of the flange of the PTO clutch pin 7 is provided on the upper side wall of the transmission case 8.
, fix the PTO clutch lever 1 to the protruding part of the PTO clutch pin 7 outside the transmission case, and install two pins 27 and 30' parallel to the PTO clutch pin on the parking bracket 10 to connect the rear two-wheel drive system and the four-wheel drive system. The feature is that the four-wheel switching lever 60 that switches the drive system and the parking brake lever 28 are each pivoted, so the levers can be gathered on one bracket 10, and the arrangement of the levers is streamlined, making it easier to operate the levers. This makes it easier to use, eliminates the need for extra brackets, and makes the structure much simpler and cheaper.

The parking bracket 10 in the present invention is attached to the side wall of the transmission case 8 with bolts 25, etc.
It engages with the outer surface of the flange 12 (FIG. 2) of the O clutch pin 7 and also serves as a retaining plate for the PTO clutch pin 7.

That is, the parking bracket 10 in the present invention is a PTO
The four-wheel switching lever 60 for switching between the rear two-wheel drive system and the four-wheel drive system and the parking brake lever 28 can be assembled by simply enlarging the conventional retaining plate for the clutch pin 7 and installing pins 27 and 30' there. ,
The structure of the bracket is simple and inexpensive.

That is, the parking bracket 10 can be easily formed by stamping a thick steel plate, etc., and is inexpensive because it does not require bending or welding.

Also, since the parking bracket 10 is fixed to the side wall of the transmission case 8, this parking bracket 10
By providing pins 27, 30', etc. at right angles to the
It can be supported in the vicinity of the O-clutch lever 1 so that it can be operated back and forth in the same way as the PTO clutch lever 1, and the number of machining steps for the transmission case 8, which facilitates the operation of the levers, is also reduced. From this point of view as well, it is effective in reducing costs.

In the present invention, since the four-wheel switching lever 60 is pivotally supported on the parking bracket 10, the four-wheel switching lever 60
Four-wheel switching clutch pin 6 at the bottom of the transmission case 8
Compared to the case where the four-wheel switching lever 60 is mounted on the vehicle, the four-wheel switching lever 60 can be easily accessed and operated.

By using the parking bracket 10, the four-wheel switching lever 60 is placed above the side of the transmission case 8 in a PTO position.
Since the clutch lever 1 and the parking brake lever 28 can be arranged in parallel, the fulcrum of each lever is close together, making it easier to approach and select the levers, as well as aligning the direction and stroke of the operating force to be applied, making it easier to operate. Improves physical fitness and reduces fatigue.

By using the parking bracket 10 in this way, it becomes possible to arrange the four-wheel switching lever 60 in a new position different from the conventional one, and the above-mentioned effects can be obtained.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of the left side of an agricultural tractor to which the present invention is applied;
2 is a partial cross-sectional view taken along the line ■--■ in FIG. 1, and FIG. 3 is a schematic cross-sectional view taken along the line I--I in FIG. 1...PTO clutch lever-17...
PTO clutch pin, 8...Mission case (gear case), 10...Parking bracket, 28...Parking brake lever, 60
...Four-wheel switching lever.

Claims (1)

[Scope of utility model registration request] PTO clutch pin 7 is located on the upper side wall of mission case 8.
Attach a plate-shaped parking bracket 10 that also serves as a retaining plate that engages with the outer surface of the flange of the PTO clutch lever 1, and fix the PTO clutch lever 1 to the outside protrusion of the PTO clutch pin 7. A four-wheel switching lever 60 equipped with a pin 27.30' to switch between rear two-wheel drive system and four-wheel drive system.
and a parking brake lever 28, respectively.