JPS6139661Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tail upper limit switch structure for a truck cab, particularly a double cab tail. Such a tail-type cab is equipped with a limit switch that stops the tail when the cab tail reaches its upper limit.

The conventional limit switch arrangement is, for example, the first limit switch.
As shown in the figure, a limit switch 2 is attached to the lower part of the cab body 1, and when the cylinder rod 3 is raised and the cab body 1 is tilted from the position shown by the chain line to the upper limit position shown by the solid line, the lever adjacent to the cylinder rod 3 A push button 2a of a limit switch 2 is pressed by a push block 6 fixed to the tip of a release lever 5 integrally formed with a release lever 4 to stop tilting and stop a warning buzzer during tilting.

In this case, since the push block 6 was fixedly attached to the release lever 5, when the cab slightly lowered from the upper limit position of the tilt, the limit switch 2 was activated immediately, the power was turned on, and a warning buzzer sounded loudly.

The purpose of the present invention is to overcome the above-mentioned drawbacks and provide mechanical hysteresis to the switch operation by attaching a holder to the limit switch and a push block restrained by an elongated hole to the release lever. After that, we created a limit switch structure for the cab tail that prevents the limit switch from operating due to a slight descent of the cab and does not emit a warning buzzer when the power switch is turned on. This is what we provide.

Next, the present invention will be described by way of examples with reference to the drawings.

FIG. 2 shows an embodiment of the present invention. In this figure, a limit switch 12 is attached to the lower part of the cab body 11, the cylinder rod 13 is raised, and the cab body 11 is at the upper limit tilt position.
A push block 16 is attached to the tip of a release lever 15 that is integrally formed with the lever 14.
It has a structure in which the pushbutton 12a of the limit switch 12 is pressed to stop the tilt and the warning buzzer, and other than the configuration of the pushblock 16 and the holder 17 attached to the limit switch 12, it is the same as the conventional one described with reference to FIG. Almost the same.

Here, the configuration of the push block 16 and the holder 17, which are the features of the present invention, will be explained in more detail.

FIG. 3 is an exploded view for explaining one embodiment of the present invention, in which the limit switch 12 has a push button 12a, and the holder 17 is attached to the lower surface of the limit switch 12. The holder 17 has a back plate 18, a fixing plate 19 having a push button hole 19a, and two legs 20, 20 extending downward from both sides of the fixing plate 19. The legs 20 are each formed with engaging portions 20a that face each other and protrude inward.
The holder 17 is made of an elastic material such as spring steel. The holder 17 is attached to the lower surface of the limit switch 12 in the fixing part 19, the push button 12a passes through the push button hole 19a, and the back plate 18 is fixed to the back of the limit switch 12 with screws or the like.

The push block 16 has an elongated hole 21 extending in the vertical direction, and recesses 22 that can be engaged with the engaging portions 20a are formed on both sides.

A U-shaped guide 23 is attached to the end of the release lever 15, and a guide pin 24 is fixed approximately at the center of the guide 23. The push block 16 is slidably supported by guides 23 on a portion of both sides, a guide pin 24 is slidably fitted into the elongated hole 21, and the holder 16 is slidably supported by guides 23.
It is supported so that it does not go beyond 4.

FIG. 4 is an explanatory diagram of the operating principle of the present invention.
is the diagram when the cab is being raised, and is at the upper limit of the cab tilt, in which the push block 16 presses the push button 12a to turn off the limit switch 12. Also, the push block 16 is attached to the holder 17.
The guide pin 24 is located at the upper end of the elongated hole 21. shows a state in which the cab is slightly lowered; in this state, the push block 16 is engaged with the holder 17, and therefore the limit switch 12 remains off. That is, even if the guide pin 24 moves from the upper part of the elongated hole 21 to the lower part, the push block 16
is engaged with the holder 17, so the push button 12a remains pressed. indicates the state in which the cab is lowered, and here push block 1
6 is removed from the holder 17 and the limit switch 12
Push button 12a away from the limit switch 1.
2 is in the on state.

When lowering the cab in actual operation,
As shown in FIG. 2, by operating the operating lever 26 attached to the lever 14 via a wire 25, the release lever 15 is lowered beyond the play of the push block 16 (the distance traveled within the elongated hole of the guide pin 24). Switch 12 is activated.

As explained above, according to the present invention, the holder attached to the limit switch and the push block attached to the release lever through the elongated hole allow
Since the limit switch is provided with mechanical hysteresis, even if the tailed cab is slightly lowered, the limit switch will not be activated immediately, and the power will be turned on and the noisy warning buzzer will sound.

[Brief explanation of drawings]

Figure 1 is a side view of a conventional limit switch, Figure 2 is a side view of an embodiment of the invention, Figure 3 is an exploded perspective view of an embodiment of the invention, and Figure 4 is an explanation of the operating principle of the invention. It is a diagram. 11...Kiyab, 12...Limit switch,
12a...Push button, 15...Release lever,
16...Push block, 17...Holder,
21...Elongated hole, 24...Guide pin.

Claims (1)

[Scope of utility model registration request] In the limit switch structure of a cab tail, a limit switch is attached to the lower part of the cab, the cab is tilted by a tail cylinder, and at the upper limit of the tip, the limit switch is pressed by a push block attached to a release lever adjacent to the tail cylinder. A holder is fixed to the surface on which the push button of the limit switch is disposed, and has two legs each having engaging portions protruding from each other, and a long hole is bored in the push block, and a holder is provided on both sides of the push block. Recesses that can be engaged with the engaging portions of the two legs are formed on the surface, and the elongated holes are slidably supported by a pin fixed to the tip of the release lever, and the depressions of the limit switch are supported in a slidable manner. A cab tail limit switch structure characterized in that when a button is pressed or released by the push block, the pin is movable in the elongated hole of the push block in the direction of displacement of the push button.