JP2712660B2 - Brake equipment for industrial vehicles - Google Patents

Description

Description: BACKGROUND OF THE INVENTION (Industrial application field) The present invention relates to a brake device used for an industrial vehicle such as a forklift. The present invention relates to a so-called deadman type brake device to be applied.

(Prior Art) This type of conventional brake device is mainly used in a reach type forklift. This is achieved by arranging a pair of brake levers so as to sandwich a brake disk connected to the rotation shaft of the traveling motor, supporting the base ends of both brake levers rotatably by a common pin, and always turning the distal end. A brake spring mounted on the side of the brake lever urges both brake levers in a direction approaching each other to apply a brake by sandwiching a brake disc with a brake pad attached to the brake lever; and When the release pedal is depressed, the substantially elliptical cam disposed between the other ends of the two brake levers is rotated via a pedal depressing force transmission mechanism to widen the distance between the brake levers and pull the brake pad from the brake disc. Release to release the brake. The return of the brake release pedal to the original position is performed by a return spring different from the brake spring. As such a mechanical disc brake device, for example, Japanese Utility Model Laid-Open No. 1-178057
Publication No.

(Problems to be Solved by the Invention) However, in the case of the above-described deadman type brake device, it is necessary for the operator to constantly depress the brake release pedal to release the brake while the vehicle is running. Therefore, the operator must always maintain the depressing force enough to overcome the reaction force of the brake (combined force of the brake spring and the return spring), and there is a problem that the load on the foot is large. In addition, if the spring force of the brake spring is set to be weak to reduce the above-described burden, the braking effect is deteriorated.

Therefore, the present invention has been made in view of the above problems, and to provide an industrial vehicle brake device capable of reducing the pedal effort required to maintain the brake in the released state without deteriorating the effectiveness of the brake, With that purpose.

(Means for Solving the Problems) In order to solve the above problems, the following measures have been taken in the present invention.

That is, in the present invention, the brake is operated by pressing the friction member against the brake disk or the brake drum by the brake spring, and the friction member is pulled from the brake disk or the brake drum against the brake spring by depressing the brake release pedal. In an industrial vehicle brake device configured to release a brake when released, the pedal is held at an arbitrary position of a pedal depression force transmission system including the brake release pedal when the brake release pedal is depressed, at a brake release position. And the holding force is set to be slightly lower than the spring force of the brake spring.

(Operation) In the brake device configured as described above, when the brake release pedal is depressed to the brake release position and the brake is released, the pedal depression force assisting means operates to hold the brake release pedal at the depressed position. I do. Therefore, the operator can hold the pedal at the brake release position with the assistance of the pedal depression force assisting means,
The treading force burden at that time is reduced. And
Since the holding force of the pedal effort assisting means is weaker than that of the brake spring, if the pedal effort by the operator is removed, the brake operation by the brake spring is performed without any trouble.
In other words, the pedal depression force assisting means operates only at the brake release position, which is the final stage of the depression stroke of the brake release pedal, and does not operate midway.

(Example) Hereinafter, an example of the present invention applied to a reach type forklift will be specifically described with reference to the drawings.

<Embodiment 1> First, a mechanical disk brake device of the deadman type will be described based on Figs. 3 to 5. In the figure, 1
Is a traveling electric motor arranged in a vertical direction. Although not shown, one end (lower end) of a rotating shaft of the electric motor 1 is connected to driving wheels via a gear reducer. The gear reducer and the driving wheels are supported as a drive unit on the body frame 10 via a suspension. A brake disc 2 is connected to the other end (upper end) of the rotating shaft of the electric motor 1.
A pair of upper and lower brake levers 3 having a brake pad 3a as a friction member are provided on the opposite surface side so as to sandwich the brake lever 3 therebetween. The base end (left end in the figure) of the brake lever 3 is rotatably supported by a common pin 3b, and both brake pads 3a are always connected to the brake disc 2 by a brake spring 4 attached to the front end. It is biased in the pressing direction.

On the other hand, a substantially elliptical cam 8 is provided between the distal ends of the upper and lower brake levers 3. This cam 8 is a cam shaft of a shift lever 7 which is tilted via a link mechanism 6 which is a pedal depression force transmission means when the brake release pedal 5 is depressed.
The brake is released by the brake pad 3a being released from the brake disk 2 by operating the brake release pedal 5 to open the brake lever 3 when the brake release pedal 5 is depressed. The rotation angle of the cam 8 when the brake release pedal 5 is depressed to the brake release position is generally set so that its long axis is approximately 60 degrees with respect to the horizontal line. The spring force of the spring 4 acts in a direction to return the brake release pedal 5 to the original position from the cam 8 via the link mechanism 6.

One end of the brake release pedal 5 has a body frame 10.
And the other end is always urged in the brake operating direction by a return spring 9 whose other end is locked to a part of the link mechanism 6, whereby the cam 8 is moved from the brake lever 3 in the brake operating state. A completely separated posture,
In other words, the posture is maintained such that the long axis is horizontal, and rattling of the brake release pedal 5 and the link mechanism 6 is suppressed. In the figure, reference numeral 11 denotes the upper surface of the floor of the driver's seat.

Next, when the brake release pedal 5 is depressed to the brake release position, pedal depression force assisting means that acts to hold the brake release pedal 5 at the same position is shown in FIGS.
Description will be made based on the drawings. This pedal depression force assisting means is constituted by a detent mechanism 18 in the present embodiment, and the support shaft 12 of the brake release pedal 5 and the link of the link mechanism 6 in the pedal depression force transmission system connecting the brake release pedal 5 and the cam 8. Support shaft 13 or shift lever 7
This is carried out with respect to an arbitrary fixed point rotating portion such as the cam shaft 8a. In the present embodiment, the case where it is assembled to the support shaft 13 in the link mechanism will be described.

That is, a substantially V-shaped detent groove 14 is formed on the outer periphery of the support shaft 13 that rotates with the link.
A spring 15 and a detent ball 17 urged by the detent spring 16 are provided on the holder 15 side for rotatably supporting the detent. When the brake release pedal 5 is depressed to the brake release position, the detent Ball 17
Are engaged with the detent grooves 14 so that their relative positions are set. The holding force of the detent mechanism 18 determined by the detent spring 16 is set to be slightly weaker than the combined force of the brake spring 4 and the return spring 9.

The mechanical disc brake device of the present embodiment is configured as described above. Therefore, when the operator steps on the driver's seat and depresses the brake release pedal 5, the link mechanism 6
In addition, since the cam 8 rotates through the shift lever 7 to spread the brake levers 3, the brake pads 3a separate from the brake disc 2 and the brake is released. Note that the depression of the brake release pedal 5 at this time requires a pedal depression force that overcomes the combined force of the return spring 9 and the brake spring 4.

On the other hand, when the brake release pedal 5 is depressed, the support shaft 13 of the link mechanism 6 rotates in the direction of the arrow as shown in FIG. 1, and the brake release pedal 5 is depressed to the maximum depression position which is the brake release position. At this time, since the detent groove 14 formed in the support shaft 13 corresponds to the detent ball 17, the detent ball 17 urged by the detent spring 16 engages with the detent groove 14 as shown in FIG. The engagement force at this time acts as a force for holding the brake release pedal 5 at the brake release position. That is, when the brake release pedal 5 is depressed to the brake release position, the pedaling force of the operator is reduced by the holding force of the detent mechanism 18.

When the depression of the pedal release pedal 5 is released, since the combined force of the brake spring 4 and the return spring 9 is larger than the holding force of the detent spring 16, the support shaft 13 is turned in the direction of the arrow in FIG. Move and detent ball
17 escapes from the detent groove 14. Then, the brake lever 3 is pulled toward the sides approaching each other by the brake spring 4, and the brake is applied by the brake pad 3 a sandwiching the brake disc 2, and the pedal release pedal 5 is in the initial position by the return spring 9. Jumped up to the brake operating position. That is, the detent spring 16 does not adversely affect the braking performance.

<Embodiment> Next, a description will be given of a second embodiment regarding the pedal depression force assisting means according to the present invention with reference to FIG. Example 2
Is a device that constitutes pedaling force assisting means using a magnet. That is, while the iron plate 19 is adhered to the back surface (lower surface) of the brake release pedal 5, the magnet 20 is adhered to the floor upper surface 11 side, and when the brake release pedal 5 is depressed to the brake release position, The iron plate 19 is attracted to the magnet 20 to add a holding force for holding the brake release pedal 5 at the same position. The holding force is the same as that of the above-described embodiment. It is set somewhat weaker by the combined force with the spring 9.

In the case of the second embodiment using such a magnet, the number of components is smaller and the assembly is simpler than that of the first embodiment, so that it is extremely advantageous in terms of manufacturing cost. The advantage that is.

In the case of the pedaling force assisting means using a magnet, as in the case of the first embodiment, not only the brake release pedal 5 but also a link, which is a constituent member of the link mechanism 6 which is a pedaling force transmission system, The present invention can be implemented between a rod or the like and a vehicle body frame 10 as a fixing member.

Further, in the illustrated embodiment, the case where the present invention is applied to a mechanical disc brake is described. However, the present invention is not limited to this, and may be applied to a drum brake. Not only a mechanical type but also a type using a cable or a hydraulic type may be used. In addition, the holding force of the pedal depression force assisting means is set to be slightly weaker than the combined force of the brake spring 4 and the return spring 9. Naturally, it is set weakly.

(Effects of the Invention) As described in detail above, according to the present invention, a part of the pedal effort required to keep the brake release pedal continuously depressed to the brake release position is borne by the pedal effort assisting means. The burden on the operator's pedaling force can be reduced. Moreover, the pedal depression assisting means of the present invention operates only at the brake release position, and does not adversely affect the braking performance.

[Brief description of the drawings]

1 and 2 are cross-sectional views showing a first embodiment relating to a pedal depression assist means, FIG. 3 is an overall explanatory view of a deadman type brake device, and FIG. FIG. 5 is a plan view, and FIG.
FIG. 6 is a side view showing a second embodiment relating to the pedal depression assisting means. 2 ... Brake disc, 3 ... Brake lever 3a ... Brake pad, 4 ... Brake spring 5 ... Brake release pedal, 6 ... Link mechanism 8 ... Cam, 18 ... Detent mechanism 19 ... Iron plate, 20 ……magnet

Claims (1)

(57) [Claims] The brake is actuated by pressing a friction member against a brake disk or a brake drum by a brake spring, and the friction member is pulled from the brake disk or the brake drum against the brake spring by depressing a brake release pedal. In an industrial vehicle brake device configured to release the brake by releasing,
It acts on an arbitrary position of the pedal depression force transmission system including the brake release pedal so as to hold the pedal at the brake release position when the brake release pedal is depressed, and the holding force is slightly greater than the spring force of the brake spring. An industrial vehicle brake device provided with a weakly set pedal depression force assisting means.