JPH0326006Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a structure for preventing the pin from falling out for towing a construction vehicle.

(Prior art) Conventionally, construction vehicles have a connecting part at the rear end of the vehicle body, and a towing pin is attached to a vertical pin hole provided in this connecting part so as to be movable up and down. It is designed to connect objects to be towed.

In order to prevent the pin from falling off or being lost, conventionally the top of the pin 101 is connected to the connecting part W with a chain 102 as shown in FIG. A locking metal fitting 103 is provided on the connecting portion W, or a locking plate 104 for locking the upper end surface of the pin 101 is fixed to the upper end of the connecting portion W as shown in FIG.

(Problem to be solved by the invention) In the above-mentioned conventional towing pin removal prevention structure, the chain stopper 10 is attached to the connection part W side of the construction vehicle.
2a, pivot brackets 103a, bolt holes, etc., which is not only troublesome in manufacturing the vehicle body, but also has disadvantages in that the above-mentioned retaining structure is exposed to the outside, making it easily damaged and undesirable in terms of appearance.

(Means for Solving the Problems) The towing pin retaining structure according to the present invention is a towing pin that is attached to a vertical pin hole provided in a connecting part at the end of a construction vehicle so as to be movable up and down. In the drawing pin, a stopper is rotatably supported near the lower end of the pin by a horizontal support shaft, and the locking part at one end projects to the outside of the outer circumference of the pin, and the locking part is pivoted upward. The stopper is urged toward the locking position by its own weight, and when the stopper is in the locking position, the stopper is moved toward the support shaft. On the other hand, a receiving part for receiving the other end on the opposite side of the locking part from above is provided near the lower end of the pin.

(Function) Since the towing pin retaining structure of the present invention is configured as described above, when the pin is installed in the pin hole, the stopper is in the retracted position and the locking part is retracted into the outer periphery of the pin. On the other hand, when the pin is moved upward and the pin comes out of the lower pin hole, the stopper is automatically switched from the retracted position to the locking position due to its own weight, and the locking part protrudes outside the outer periphery of the pin and the stopper is removed. Since the other end is received by the receiving portion from above and the stopper is restricted from rotating, the locking portion of the stopper comes into contact with the lower end surface of the upper pin hole and the pin is prevented from coming out.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

Figure 1 shows a state in which a towing pin 1 is attached to an upright pin hole 2 provided in a connecting part W at the rear end of a construction vehicle, and Figure 2 shows a towing arm 3 of an object to be towed.
The pin 1 is shown partially pulled upward in order to attach and detach.

A towing arm 3 is attached to the middle part of the connecting part W from the rear.
The pin hole 2 is divided into a lower pin hole 2b below the recess 4 and an upper pin hole 2a above the recess 4.

As shown in FIGS. 3 and 4, the towing pin 1 includes a pin body 5, a pair of brackets 6 vertically disposed at the lower end of the pin body 5, and a horizontal portion near the lower end of the bracket 6. A stopper 8 is rotatably supported by a support shaft 7, and a receiving plate 9 is fixed to the lower end of the pin body 5 and the side end surfaces of both brackets 6, and the lower end thereof is slightly above the support shaft 7. It consists of a receiving plate 9, a rod 10 erected at the upper end of the pin body 5, and a handle 11 fixed to the upper end of the rod 10.

The length from the support shaft 7 to one end 8a of the stopper 8 is approximately twice the length from the support shaft 7 to the other end 8b of the stopper 8, and a locking portion 8A is formed at one end of the stopper 8. A received portion 8B is provided on the upper surface of the other end of the stopper 8, and the stopper 8 has a substantially horizontal locking position where the locking portion 8A largely protrudes outside the outer periphery of the pin body 5, and a locking portion 8B. The rocking position can be freely switched between a retracted position in which the portion 8A is rocked upward and retracted into the outer periphery of the pin body 5, and when the stopper 8 is in the locking position, the received portion 8B is received from above by a receiving portion 9a at the lower end of the receiving plate 9, and its rotation in the clockwise direction in FIG. 3 is restrained, and the stopper 8 is moved to the locking position by its own weight. It's becoming more energizing.

The lower side of the locking portion 8A of the stopper 8 is cut into a tapered shape, and when the stopper 8 is in the retracted position, this tapered surface 8t is in a state along the outer periphery of the pin body 5, and the stopper 8 is in the locking position. At times, the tapered surface 8t serves as a guide surface when the towing arm 3 is attached.

In the above configuration, when the pin 1 is inserted into the pin hole 2 from above, the stopper 8 swings upward to the retracted position, so that the pin 1 can be inserted into the pin hole 2 as shown in FIG. In this case, the support parts 11a at both ends of the handle 11 of the pin 1 are locked to the upper end surface of the connecting part W, so that the pin 1 does not fall off downward.

When the pin 1 moves upward and comes out of the lower pin hole 2 due to the vertical movement of the construction vehicle, the stopper 8 is automatically switched to the locking position by its own weight, so the stopper 8 is moved upward as shown in FIG. Since the locking portion 8A of the pin 8 contacts and locks the lower end surface 4a (upper wall of the recess) of the upper pin hole 2a, the pin 1 is reliably prevented from coming out.

Further, the towing arm 3 can be attached and detached with the pin 1 in the state shown in FIG. 2.

Incidentally, as shown in FIGS. 5 and 6, the pair of brackets 6 may be formed integrally with the pin body 5, and the receiving portion 9a may also be formed integrally with the pin body 5.

(Effect of the invention) In the towing pin retaining structure according to the present invention, as explained above, the pin is prevented from being withdrawn by the stopper provided near the lower end of the pin, so various parts of the retaining structure are Since these parts are not exposed to the outside of the connecting part, they are not damaged by objects hitting them from the outside, and the appearance is also improved.

Further, since there is no need to perform any work on the connecting portion for the above-mentioned slip-out prevention structure, it is also preferable in terms of manufacturing the vehicle body.

[Brief explanation of the drawing]

Of the drawings, Figures 1 to 6 show embodiments of the present invention, with Figure 1 being a longitudinal cross-sectional side view of the connecting part showing the state in which the towing pin is attached to the connecting part, and Figure 2 being a side view of the connecting part showing the state in which the towing pin is attached to the connecting part. Figure 3 is a side view of the connecting part showing the state in which the pin is not removed; Figure 3 is a side view of the towing pin;
The figure is a front view of the towing pin, Figure 5 is a modified example equivalent to Figure 1, Figure 6 is a front view of the main parts of the towing pin, and Figures 7 to 9 each show the prior art. , FIGS. 7 and 8 are views corresponding to FIG. 1, and FIG. 9 is a view equivalent to FIG. 2. W... Connection part, 1... Towing pin, 2...
Pin hole, 2a...upper pin hole, 2b...lower pin hole, 7...support shaft, 8...stopper, 8A...locking part, 9a...receiving part.

Claims (1)

[Scope of Claim for Utility Model Registration] In a towing pin that is vertically movably attached to a vertical pin hole provided in a connecting part at the end of the vehicle body of a construction vehicle, a stopper is horizontally supported near the lower end of the pin. A locking position where the locking part at one end of the pin is rotatably supported by a shaft and protrudes outside the pin's outer periphery, and a retracted position where the locking part is swung upward and retracted into the pin's outer periphery. The stopper is urged toward the locking position by its own weight, and when the stopper is in the locking position, the other end on the opposite side of the locking part is moved upward with respect to the support shaft. A towing pin retaining structure characterized in that a receiving part for receiving the pin is provided near the lower end of the pin.