JPH0526083Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to the improvement of a braking device for rolling compaction machines, and in particular, when the brake pedal is pressed while traveling forward or backward, the forward/reverse lever automatically stops. The present invention relates to a braking device for a rolling compact machine that is configured to switch to a set position and then operate after a time lag.

[Conventional technology]

Conventionally, hydraulically driven compaction machines used for road paving work, etc., move forward, stop, and run backwards by operating the forward and backward levers, and when stopping, the forward and backward levers are switched to the stop setting position. The vehicle is configured in such a manner that the connection between the drive source and the drive wheels is cut off, and then the brake pedal is depressed to apply braking.

Moreover, the forward/reverse lever, which performs forward, stop, and reverse travel operations, and the brake pedal, which brakes travel, are not mechanically linked at all.

For this reason, conventional compaction machines have had the disadvantage that unless the forward/reverse lever is manually switched to the stop setting position, even if the brake pedal is pressed to apply braking, the driving force will continue to drive the vehicle and no braking action will be achieved. Therefore, it is extremely dangerous, and if the brake pedal is forcibly depressed, the brake shoes and plates of the main brake will wear out, shortening their useful life.

Therefore, the present applicant solved this problem by linking the forward/reverse lever and the brake pedal in the following manner, as disclosed in Japanese Utility Model Application No. 61-146506 for a hydraulically driven compaction machine. I tried.

FIGS. 4 and 5 show the coordination mechanism, and the set position of the forward/reverse lever 11 is set between the forward/reverse lever 11 and the brake pedal 12 in conjunction with the up/down movement of the brake pedal 12. It is constructed with lever switching means 13 for switching from the forward A or reverse C setting position to the stop setting position B. This lever switching means 13 is composed of a plate-shaped oscillating body 14 and two transmission devices 15, 15'.
is the base shaft 1 of the forward/reverse lever 11 so that both swing ends 14a, 14a' swing vertically in a scale-like manner.
6, which allows the forward/backward movement lever 11 to move forward, stop,
It is designed to oscillate in conjunction with the reverse segmentation operation. Engagement parts 13a and 13a' formed by pin bodies are formed at both swinging end edges of the swinging body 14, and the engagement parts 13a and 13a' are connected to the transmission tools 15 and 15'.
An engaging portion 1 consisting of a slide hole formed at the tip of the
3b and 13b'. And transmission gear 1
The proximal ends of 5 and 15' are pivotally connected to a fixed shaft 12a of a brake pedal 12 which is supported by a fixed shaft 12a, and when the brake pedal 12 is depressed downward, the transmission devices 15 and 15' are interlocked. It is designed to be pulled down.

Incidentally, FIG. 4 shows the state in which the forward/reverse lever 11 is set at the forward travel setting position A, that is, the state during forward travel. It is in contact with the upper surface of the engaging portion 13b' formed by the slide hole of the transmission tool 15'. When the brake pedal 12 is pressed in this state, the transmission gear 1
5' is lowered in conjunction, lowering the rear swinging end 14a' and bringing both swinging ends 14a, 14a' of the swinging body 14 into a substantially horizontal state. As a result, in conjunction with the rocking body 14, the forward/reverse lever 11 moves from the position A to the set stop position B.
It can be switched up to

Conversely, move the forward/reverse lever 11 to the reverse setting position C.
When set to , the swing end 14a on the left in the figure is tilted upward, and the upper surface of the pin body of the engaging portion 13a is aligned with the upper surface of the slide hole of the engaging portion 13b of the transmission device 15, contrary to the case of forward travel. I will come into contact with you. Therefore, when the brake pedal 12 is depressed in this state, the transmission device 15 is lowered and the front swinging end 14a is pulled down to bring both swinging ends 14a, 14a' of the swinging body 14 into a substantially horizontal state. As a result, the forward/reverse lever 11 is configured to be automatically switched from the reverse travel set position C to the stop set position B in conjunction with the rocking body 14.

Next, the fixed shaft 12a of the brake pedal 12
A switch operating portion 12b that is linked to the vertical movement of the brake pedal 12 is provided at the side end. This switch operating section 12b is configured with a micro switch 17 that is set to remain on in normal conditions, and is switched off as soon as the brake pedal 12 is depressed, and turns on and off the negative brake described below. It functions as a changeover switch for turning off the switch.

As is well known, the braking device as a negative brake includes a disc 18 attached to a cylindrical case, a piston-shaped braking body 19 attached to the disc 18, and a resilient material 2.
Normally, hydraulic pressure is applied between the disc 18 and the piston-shaped brake body 19, and by releasing this hydraulic pressure, the piston-shaped brake body 1
9 is brought into pressure contact with the disc 18 by the resilient material 20, and exhibits a braking function. That is, when the brake pedal 12 is depressed, the micro switch 1
7 is turned off, the electromagnetic switching valve 23 in the hydraulic circuit that supplies hydraulic pressure from the hydraulic pump 22 directly connected to the engine 21 to the braking device is switched, and the hydraulic fluid that was releasing the brake is transferred to the hydraulic fluid tank. 2
4 is configured so that an escape brake is applied.

[Problem that the invention attempts to solve]

However, in the braking device disclosed in Japanese Utility Model Publication No. 61-146506, due to the restraint of the lever switching means 13, the depression stroke of the brake pedal 12 reaches its maximum stroke when the forward/reverse lever 11 returns to the stop setting position (no more than At this position, the braking device, specifically the micro switch that controls the on/off of the negative brake, is activated, and the negative brake is activated at the same time as the forward/reverse lever 11 is switched to the stop setting position. The brakes are now applied. However, even if the forward/reverse lever 11 is switched to the stop setting position and the hydraulic pump 22, which is the drive source, is stopped, the drive force remains in the hydraulic circuit of the drive system until the stop balance is maintained (until the inertia force is balanced). is in a state of That is, there is no time lag between switching the forward/reverse lever 11 to the stop setting position and applying the brake, and they operate simultaneously. Therefore, since the negative brake is activated with this driving force remaining, the problem remains that the load on the brake is large and the lining of the brake shoe (braking body) wears out, shortening its useful life. Furthermore, the invention disclosed in Japanese Utility Model Application No. 61-146506 can be applied to brakes such as negative brakes in which braking is turned on and off by a switch, but the brake force can be adjusted by changing the depression stroke of the brake pedal 12. Another problem was that it was unsuitable for drum brakes, disc brakes, etc. used in general vehicles that can adjust the speed.

This invention was devised in view of the above problems, and it does not cause abnormal wear on the lining of the brake shoe (braking body), and can also be applied to drum brakes, disc brakes, etc. used in general vehicles. To provide a braking device for compaction machines.

[Means for solving problems and their effects]

In order to solve the above problems, the present invention includes a brake that brakes the rolling wheel, a brake pedal that starts operating the brake by a predetermined depression amount, and a forward/reverse lever that controls the travel drive system. A rocking body that rocks each time the forward/reverse lever is operated; a transmission device that is attached to the brake pedal side of the rocking body and cooperates to return the forward/backward lever to the stop setting position; and an elastic body having a spring constant that returns the forward/reverse lever to a set stop position before the brake pedal is depressed to a predetermined depression amount.

By adopting the above configuration, when the brake pedal is depressed, the forward/reverse lever is first switched to the stop setting position, and then the braking device is activated. That is,
Since an elastic body is interposed in the middle of the transmission, when the brake pedal is depressed, the forward/reverse lever is first switched to the stop setting position, and then the braking device is activated with the set lime lag, resulting in a two-stage action operation. It performs the function of carrying out. As a result, the brakes are activated after the driving force has almost stopped, which prevents abnormal wear on the lining of the brake shoe (braking body), and is suitable for braking devices such as drum brakes that require adjustment of the braking force. can also be applied.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a system explanatory diagram of a first embodiment using a negative brake, FIG. 2 is a sectional view of a main part of a transmission, and FIG. 3 is a system explanatory diagram of a second embodiment using a drum brake. Incidentally, members common to those in FIGS. 4 and 5 are designated by the same reference numerals, and explanations thereof will be omitted.

In the first embodiment, the present invention is applied to a rolling machine using a negative brake. As shown in FIGS. 1 and 2, springs 1 and 1' are interposed in the middle of the transmission tools 15 and 15'. The springs 1 and 1' have a tension greater than the force that returns the forward/reverse lever 11 to the stop setting position in the first step when the brake pedal 12 is depressed, and may be a compression spring 1a or a tension spring. In the case of the compression spring 1a, as shown in FIG. 2, the transmission tool 15 is divided into two from the middle, and the lower side is the rod 2, and the upper side is the box body 3 and an engaging portion 13b consisting of a slide hole. The compression spring 1a is now wound between a washer 2b that is engaged with the box body 3 near the middle nut of the rod 2 by a snap spring 2a, and a washer 2c that is welded to the tip of the rod 2. has been done. When the rod 2 is pulled, the compression spring 1a is compressed by the washer 2b inside the box body 3.
and the washer 2c.

In FIG. 1, a cam 4 is attached to a fixed shaft 12a of a brake pedal 12, and the springs 1,
Together with the elastic force 1', the opening and closing of the contacts of the micro switch 17 that activates the negative brake can be adjusted freely.

With this construction, when the brake pedal 12 is depressed, the rod 2 or 2' of the transmission 15 or 15' is depressed in the first step. At this time, since the tension of the compression spring 1a is set to be greater than the force that returns the forward/reverse lever 11 to the set stop position, the tension of the compression spring 1a
Or, 1a'(1a' is not shown) is not compressed and transmits the pushing force to the box body 3 or 3' in almost the set state, so that both swinging ends 14a, 14a' of the swinging body 14 are held approximately horizontally. and return the forward/reverse lever 11 to the stop setting position. When the brake pedal 12 is further depressed, the rods 2 and 2' are further depressed, and the washers 2c and 2c'(2c') welded to the rods 2 and 2' are pressed down.
Only the compression springs 1a and 1a'(1a' is not shown) are compressed by the compression springs 1a and 1a'(1a' is not shown). After a time lag due to this compression, the micro switch 17 operates in the second step, switches the electromagnetic switching valve 23, and releases the oil from the brake system into the hydraulic oil tank 24, so that the piston-shaped brake body 19 is activated by the elastic material 20. The brakes are applied when the brakes come into close contact with the disc. Therefore, the return of the forward/reverse lever 11 to the set stop position in the first stage causes the hydraulic pump 22 to stop earlier than the action of the braking device, so that the hydraulic circuit can maintain balance and the lining of the braking body It is possible to eliminate the problem of wear.

Next, a second embodiment in which the present invention is applied to a compaction machine using a drum brake will be described.

In FIG. 3, 12 is a brake pedal. The following transmission member is attached between the brake pedal 12 and the drum brake 5.
That is, 6a is the rod, 6b is the first L-shaped arm, and 6
C is a rod, 6d is a second L-shaped arm, 7 is a metal fitting with a slide hole, and 8 is a rod. The forward and backward movement lever 11 is attached to the first L-shaped arm 6b.

In the second embodiment, springs 1, 1' are also used in the middle of the transmission tools 15, 15'. The configuration of the springs 1, 1' is similar to that of the first embodiment, and may be either a compression spring or a tension spring.

With this configuration, when the brake pedal 12 is depressed, each transmission member is interlocked as shown by the arrow. 1st
At this stage, the forward/reverse lever 11 returns to the stop setting position as in the first embodiment. At this time, slide hole fitting 7
The stroke is released through the elongated hole 7a. Further, when the brake pedal 12 is depressed, the elongated hole 7 is released as a second step.
The tip of the second L-shaped arm 6d comes into contact with the left end of a,
Since the rod 8 moves to the left in FIG. 3, the brake shoes 9, 9 are expanded by the cam 10 to apply the brakes.

As described above, the present invention can be suitably used for drum brakes, etc., in which the braking force can be adjusted by the depression stroke of the brake pedal.

In the embodiments of the present invention, a compression spring was described as the elastic body, but a tension spring, a rubber member, etc. may also be used, and when the brake pedal is depressed, the tension that returns the forward/reverse lever to the stop setting position and the stroke that activates the brake are used. Any material that has a deflection etc. that can obtain this may be used.

[Effect of idea]

As explained above, according to the present invention, an elastic body having a spring constant that returns the forward/reverse lever to the set stop position before the depression of the brake pedal reaches a predetermined amount is interposed in the transmission device. Therefore, when the brake pedal is depressed, the forward/reverse lever is first switched to the stop setting position, and then the braking device is activated, so in negative braking, the inertial force is reduced and the brake shoe (braking body) is No abnormal wear on the lining.
Furthermore, the braking device of the present invention can be applied to drum brakes and the like used in general vehicles, which have been difficult to apply with conventional devices.

[Brief explanation of drawings]

Fig. 1 is a system explanatory diagram of the first embodiment in which the present invention is applied to a rolling compaction machine using a negative brake;
Fig. 2 is a sectional view of the main parts of a transmission device using a compression spring, Fig. 3 is a system explanatory diagram of a second embodiment in which the present invention is applied to a compaction machine using a drum brake, and Fig. 4 is a diagram of a conventional transmission device. FIG. 5 is a side view showing the relationship between the brake pedal and the forward/reverse lever, and is a system explanatory diagram of a rolling press machine using a conventional negative brake. 1... Spring, 2... Rod, 3... Box body, 4...
...Cam, 5... Drum brake, 7... Metal fitting with slide hole, 11... Forward/forward lever, 12... Brake pedal, 13... Lever switching means, 14...
Oscillating body, 15, 15'... Transmission tool, 17... Micro switch, 18... Disk, 19... Braking body, 20... Resilient material, 22... Hydraulic pump, 23
... Solenoid switching valve, 24 ... Hydraulic oil tank.

Claims (1)

[Scope of utility model registration request] A brake that brakes a rolling wheel, a brake pedal that starts operating the brake by a predetermined depression amount, a forward/reverse lever that controls a travel drive system, and a rocking body that swings each time the forward/reverse lever is operated. , is attached to the brake pedal side of this rocking body,
a transmission device that cooperates to return the forward/reverse lever to the stop setting position; and a transmission device interposed in the middle of the transmission device,
A braking device for a rolling compaction machine, comprising: an elastic body having a spring constant that returns the forward/reverse lever to a set stop position before the depression of the brake pedal reaches a predetermined depression amount.