JPH0428865Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a brake equalizer device for a passenger work vehicle such as a tractor, and in particular a brake equalizer that can evenly distribute the braking force to the left and right wheels. It is related to the device.

[Prior art] In passenger working vehicles such as agricultural tractors,
Since the vehicle travels on rough terrain, sandy terrain, etc., it is necessary to apply braking effects independently to the left and right wheels to achieve reliable braking. Therefore, in order to brake the left and right wheels, two independent brake pedals corresponding to the left and right wheels are generally provided on the vehicle body.
When driving on a road, the left and right brake pedals are usually connected to apply braking at the same time.

However, from the viewpoint of simplicity and ease of braking operation, a type of riding vehicle such as a tractor that applies a braking effect to the left and right wheels with a single brake pedal is also provided. In this system, if the braking method of two brake pedals is maintained, even a slight difference in the adjustment of so-called brake play will result in a one-sided state, which tends to cause phenomena such as lateral vibration. Therefore, in the case of a single brake pedal system, for example, as seen in the hydraulic brake system disclosed in (US.PAT.NO.3220189), the rotation of the brake pedal is controlled through an equalizer device. Although it is well known that the hydraulic brake system transmits the signal to a master cylinder and brakes the left and right front wheels and/or the left and right rear wheels by the hydraulic operation of this master cylinder, the equalizer employed in such hydraulic brake systems In this device, the center part of the equalizer arm is swingably attached to the brake pedal, and the rod end of the master cylinder is attached to the free end of the equalizer arm that faces the left and right sides with equal length, and the displacement of the equalizer arm is controlled via the rod. This is intended to equalize the pressure on the brake shoes of the master cylinder by transmitting it to the left and right master cylinders.

However, the equalizer device with the above structure requires a connection between the brake pedal and the equalizer arm,
Since the equalizer arm and the brake rod are connected by respective pivot pins, there are a large number of connecting parts, and the equalizer arm has sufficient resistance to twisting, rotation, etc. caused by repeated depression of the brake. There was a problem that strength and durability could not be obtained.

[Means and actions for solving problems]

In order to solve the above-mentioned problems, the present invention has been developed for a pedal shaft in which a central equalizer arm that is directly connected to the brake pedal and left and right equalizer arms that are equally spaced on both sides of the equalizer arm are pivoted to the main frame. At the same time, an equalizer shaft parallel to the pedal shaft is lockably inserted into an insertion hole provided in each equalizer arm, and left and right brake rods connected to the equalizer arm or the pedal shaft are attached to the pedal shaft. By arranging the brakes in the same direction and at a fixed distance from the axis of the brakes, we provide a brake equalizer device that has a simple structure and can provide more accurate braking effects than conventional brakes, with improved reliability. This is what I am trying to do.

〔Example〕

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

FIG. 1 is a side view for explaining the outline of a riding work vehicle to which a brake equalizer device according to the present invention is applied.

The riding work vehicle 1 has an engine at the front of a vehicle body 2, a handle 3, and a riding seat 4. The front wheels 5 and rear wheels 6 can be rotated and driven in unison by the power of the engine. A brake mechanism 7 is attached to each of the front wheels 5 and the rear wheels 6. The brake mechanism 7 is operated by depressing the brake pedal 8 to rotate an equalizer device, which will be described later, and actuating the brake arm 11 via the left and right brake rods 9 and 10.

FIG. 2 is a perspective view of essential parts of the brake equalizer device according to the present invention. In this embodiment, an equalizer device related to a brake mechanism 7 for left and right wheels of a rear wheel 6 will be described as shown in the drawing.

The equalizer device according to the present invention includes a central equalizer arm 12 and left equalizer arms 17 disposed on the left and right sides of the central equalizer arm 12.
and the right equalizer arm 18, the center equalizer arm 12, and the left and right equalizer arms 1.
The equalizer shaft 20 is inserted into an insertion hole formed at the upper end of each of the equalizer shafts 7 and 18.

The central equalizer arm 12 is integrally attached to the brake pedal 8, and a pedal shaft 15 pivoted to the main frame 14 is inserted through sleeve sleeves 13 protruding from both sides of the lower part of the central equalizer arm 12. 1
The brake pedal 8 is rotatable about the fulcrum 5. When the brake pedal 8 is depressed, the central equalizer arm 12 is rotated by a predetermined angle, and the left and right equalizer arms 1
7 and 18 to transmit a predetermined displacement. Further, a parking brake ratchet plate 16 is provided upright on the sleeve 13.

As shown in the figure, the left equalizer arm 17 has a sleeve tube 13a extending on both sides of the lower part of the left equalizer arm 17, through which the pedal shaft 15 is inserted, and a pin 19 inserted through one side of the sleeve tube 13a.
It is fixed to the pedal shaft 15 by the left equalizer arm 17, and is adapted to transmit rotational displacement of the left equalizer arm 17 to the pedal shaft 15. Further, the right equalizer arm 18 has a pedal shaft 15 inserted through a sleeve sleeve 13b integrally provided at the lower part of the right equalizer arm 18, and is rotatable about the pedal shaft 15 as a fulcrum. The left equalizer arm 17 and the right equalizer arm 18 are disposed on the pedal shaft 15 on both sides of the center equalizer arm 12 at equal distances from each other.

The equalizer shaft 20 has a flange 20a located between the center equalizer arm 12 and the right equalizer arm 18 at a predetermined interval to prevent the equalizer shaft 20 from falling off.
20a is provided protrudingly, and this equalizer shaft 2
0, first insert one end of the equalizer shaft 20 (the free end without the flanges 20a, 20a) into the insertion hole 1 of the left equalizer arm 17.
7a and the insertion hole 12 of the central equalizer arm 12
After communicating with a, each equalizer arm 12, 17,
18 and is set. The equalizer shaft 20 is connected to the right equalizer arm 1 by a spring S (see FIG. 3) interposed between the right side surface of the central equalizer arm 12 and the flange 20a.
It is designed to be biased towards the 8 side.

By the way, the equalizer arm 12,1
The distances between the centers of the insertion holes 12a, 17a, 18a of 7 and 18 and the axis of the pedal shaft 15 are set at equal intervals, and the equalizer shaft 20 is provided parallel to the pedal shaft 15.

As shown in the figure, the pedal shaft 15 extends beyond the main frame 14 to the brake arm 11 of the left wheel.
The left brake rod 9 extends leftward to a position where the left brake rod 9 is connected, and the left brake rod 9 is connected via a clevis 22 to a mounting arm 15a provided at its free end. On the other hand, the right brake rod 10 is directly connected to the right equalizer arm 18 via a clevis 22 (see FIGS. 2 and 3).

By the way, the mounting position of the left brake rod 9 and the right brake rod 10 described above, that is, the mounting arm 15a by the rod pins 23, 23 provided on the respective clevises 22, 22 of the left and right brake rods 9, 10 is
The mounting positions for the right equalizer arm 18 and the right equalizer arm 18 are set in the same direction and at a constant distance from the axis of the pedal shaft 15.

In this embodiment, the left brake rod 9 is attached to the pedal shaft 15, but the left equalizer arm 1
Alternatively, the left brake rod 9 may be directly connected to the left brake rod 9 via the clevis 22. In this case as well, the distances between the rod pins 23, 23 provided on the respective clevises 22, 22 of the left and right brake rods 9, 10 and the axis of the pedal shaft 15 must be set in the same direction and at a constant distance. but,
It goes without saying that the left equalizer arm 17 is rotatably attached to the pedal shaft 15 in the same manner as the right equalizer arm 18 in order to transmit its movement to the left brake rod 9.

In the figure, 24 is a turnbuckle for adjusting the length of the brake rods 9, 10, and 25 is a return spring for the brake pedal. Further, in place of the flanges 20a, 20a, a bulging step for locking may be provided between the center equalizer arm 12 and the right equalizer arm 18 in order to prevent the equalizer arm from falling off. It is.

Since the present invention is configured as described above, when the brake pedal 8 is depressed during normal driving, the pedal force is transmitted to the left and right brake rods 9, 10, and the brake shoe and brake drum are operated via the brake arm 11. Normal braking action can be obtained. However, if there is a difference in the braking force of either the left or right wheel due to unevenness of the running surface or a difference in frictional force with the running ground, the depression force of the brake pedal 8 is integrally connected to this. A left equalizer arm 17 and a right equalizer arm 18 are attached at equal intervals on both sides of the central equalizer arm 12, and the axis of the pedal shaft 15 is attached to the central equalizer arm 12, left equalizer arm 17, and right equalizer arm 18. Equalizer shaft 20 parallel to and equally spaced from
is inserted, and the left and right brake rods 9 and 10 are attached with the distance between the rod pin 23 and the pedal shaft 15 set to be the same, so that the pressing force of the brake pedal 8 is equal to the distance between the rod pin 23 and the pedal shaft 15. The left equalizer arm 17 and the right equalizer arm 1 on both sides of the
8 will be transmitted evenly. At this time, the central equalizer arm 12 is fixed to the pedal shaft 15, the left equalizer arm 17 and the right equalizer arm 18 are pivotally connected to the pedal shaft 15, and the equalizer shaft 20 is inserted through each of the equalizer arms 12, 17, 18. Hole 12a, 1
7a, 18a, the equalizer shaft 20 is displaced as shown in FIG.
Since the brake rods 8 rotate, the brake rods 9 and 10 are operated according to the difference in braking force applied to the wheels.

The above relationship will be explained in detail below.

As shown in FIGS. 3 and 5, the central equalizer arm 12 and the left and right equalizer arms 1
7 and 18, L _R = L _L and are set at equal intervals. Furthermore, as shown in FIG. 4, a central equalizer arm 12, a left equalizer arm 1
7 and the insertion hole 12 of the right equalizer arm 18
a, 17a, 18a center and pedal shaft 15
The distance between the center of the rod pin 23 of the left and right brake rods 9 and 10 and the center of the axis of the brake shaft 15 is R _RR = R _ER = R _EL = R _EC . R _RL and set at equal intervals.

Then, if the pedal effective arm length is R _P and the pedal depression force is P, then the contact point of the central equalizer arm 12 with the equalizer shaft 20 is F _S , that is, F _S ×R _EC = P × R _P ∴ according to the following formula. A tangential force of F _S =P×R _P /R _EC acts (Figure 5A).

F _S acting on the equalizer shaft 20 from the brake pedal 8 via the central equalizer arm 12 is
Since L _R = L _L , 1/2 is transmitted to each of the left and right equalizer arms 17 and 18. This also holds true even if the equalizer shaft 20 is tilted as shown in FIG. 5B.

From F _R ×L _R =F _L ×L _L ... F _S =F _R +F _L ... _{L R} = _{L L} ...... From the relationship in Figure 5 _C , left and right brake rod tension
F _{RRT and F RLT are} given _{by the above formulas and formulas .} Ru.

Here, since COSθ _R ≒COSθ _L ≒1 can be practically set, in this case, it can be assumed that F _RRT =F _RLT .

Therefore, it is possible to practically equalize the tension of the left and right brake rods 9, 10 until the inclination of the equalizer shaft 20 is about 15 degrees, and the braking force to the wheels can be equalized on the left and right sides.

[Effect of idea]

Since the present invention is constructed as described above, the structure is simple, and moreover, a braking effect with improved precision and reliability than before can be obtained, and the side-to-side vibration phenomenon of the vehicle body observed in conventional tractors is eliminated. or,
It is possible to provide a brake equalizer device with significantly improved strength and durability.

[Brief explanation of the drawing]

Fig. 1 is a side view for explaining the outline of a riding work vehicle to which the brake equalizer device according to the present invention is applied, Fig. 2 is a perspective view of the main part, Fig. 3 is a plan view of the main part, and Fig. 4 is a Figure 3 side view, Figure 5 A, B,
C is an explanatory diagram for explaining the braking effect. 1... Passenger work vehicle, 5... Front wheel, 6... Rear wheel, 7... Brake mechanism, 8... Brake pedal, 9... Left brake rod, 10... Right brake rod, 12... Central equalizer arm, 1
2a, 17a, 18a...insertion hole, 13, 13
a, 13b...Sleeve sleeve, 15...Pedal shaft,
17...Left equalizer arm, 18...Right equalizer arm, 20...Equalizer axis, 23
... Rod pin.

Claims (1)

[Scope of utility model registration request] A central equalizer arm directly connected to the brake pedal and left and right equalizer arms provided at equal intervals on both sides of the equalizer arm are attached movably to a pedal shaft that is pivoted to the main frame, and are attached to the pedal shaft. Parallel equalizer shafts are lockably inserted into the insertion holes provided in each of the equalizer arms, and the left and right brake rods connected to the equalizer arm or the pedal shaft are inserted in the same direction and at a certain distance from the axis of the pedal shaft. A brake equalizer device characterized in that the brake equalizer device is arranged so as to have a brake equalizer device.