JPS5826829Y2 - Rear door opening/closing device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rear sliding door opening/closing device for automatically opening and closing a sliding door provided at the rear opening of a loading platform in a dump truck or the like.

Generally, the rear sliding door of a loading platform in a dump truck or the like has a pivot portion at the upper end, and when the loading platform is dumped, the rear sliding door opens around the pivoting portion.There is a so-called bottom-opening rear sliding door.

When discharging loaded items, this downward-opening type rear sliding door tends to cause loaded items to get caught on the rear sliding door, causing problems in ejection.

For this purpose, a method was adopted in which a pivot point was provided at a position one step higher than the height of the loading platform and the sliding door was opened wide, but this had the disadvantage of having the pivot point protrude above the loading platform. Another drawback was that large objects could collide with the sliding door.

FIG. 1 shows a schematic diagram of another conventional loading platform, where A shows the loaded state and B shows the unloaded state.

In the figure, a loading platform 1 has an opening 2 and a sloped part 3 at the rear, and the sloped part 3 prevents loaded items 4 from being discharged in a loaded state.

As the loading platform 1 tilts around the support shaft 6 of the truck 5,
The inclined portion 3 becomes horizontal, and the loaded object 4 is discharged from the opening 2.

At this time, the loaded object 4 collides with the inclined portion 3, causing the front side of the loading platform 1 to jump up, resulting in damage to the loading platform 1 and its components.

In view of the above-mentioned points, it is an object of the present invention to provide a rear sliding door opening/closing device that eliminates the drawbacks of the prior art, ensures reliable opening/closing operations, facilitates ejection of loaded objects, and prevents damage to the loading platform. shall be.

According to the present invention, this purpose is achieved by a loading platform mounted on a truck frame and tiltably supported by a loading platform support shaft, and a loading platform provided at the rear opening of the loading platform, which can be opened and closed by a lower hinge shaft. a first link fixed to a sliding door drive shaft provided on the loading platform; and a first link fixed to the sliding door driving shaft at a predetermined angle with the first link and having a support portion at its tip. a link mechanism consisting of two links, a third link provided on the lower hinge for rotating the sliding door, and a lever connecting the first and third links; A supporting part and a corresponding fixing base are provided, and when the loading platform is tilted, the supporting part of the second lever comes into contact with the fixing base to move the sliding door in the closing direction or move the sliding door away from the sliding door. Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows a schematic configuration diagram of an embodiment of the present invention, where A is a front view in a horizontal state, B is a plan view, and FIG. 3 is a schematic diagram of the tilted state of the present invention in FIG. 2. 0 In Figures 2 and 3, 7 is the loading platform, 8 is the main girder of the loading platform,
9 is a sliding door, 10 is a sliding door holder at the tip of the main girder 8, and 11 is a sliding door drive shaft.

The link mechanism 12 includes a first link 13 . 214° Consists of a third link 15 and a lever 16 that connects the links 13 and 15.

Among these, the links 13 are two links fixed to both ends of the sliding door drive shaft 11.

The links 15 are two links fixed to both ends of a lower hinge shaft 17 that is provided at the rear opening of the loading platform I and allows the swing door 9 to rotate freely.

These links 13 and 15 are connected by a lever 16.

Further, the link 14 maintains a predetermined angle a with the link 13, is fixed to the sliding door drive shaft 11, and has a rotating roller 1 at its tip.
A support part 18 having a diameter of 8A is provided.In addition, the fixed base 2
0 is fixed to the follower beam (subframe N9) of the vehicle body frame, and is formed so as to correspond to the support portion 18 of the link 14 on its upper surface.

Furthermore, the loading platform support shaft 21 supports the loading platform 7 and pivotally supports the loading platform 7 so as to be tiltable.

Next, the operation of the present invention having the above-described configuration will be explained.

When the loading platform 7 is in a horizontal state as shown in FIG. It has a driving force that allows it to move.

This force generates a rotational force for the lever 16 in the direction of arrow B and the lower hinge shaft 17 in the direction of arrow C.

Therefore, the sliding door 9 holds the loading platform 7 in a closed state.

As shown in FIG. 3, the loading platform 7 is centered around the loading platform support shaft 21.
As the link 14 tilts, the rotating roller 18A of the link 14 tends to move away from the upper surface of the fixed base 20.

For this reason, the weight of the large loaded object and the own weight of the door 9 cause the door 9 to rotate about the hinge shaft 17 in the direction of the arrow C0, which is the opening side, and the lever 16 is moved by the arrow B0.
In this direction, the sliding door drive shaft 11 generates a rotational force in the direction of the arrow A0.

The rotating roller 18A of the link 14 holds the sliding door 9 while contacting the fixed base 20.

As the tilting state of the loading platform 7 progresses, the sliding door 9 opens wide, and finally the sliding door holder 10 and the sliding door 9 come into contact, and the surface of the loading platform 7 and the surface of the sliding door 9 are almost on the same plane. When this is reached, the sliding door 9 stops in this state, and the operation of the link mechanism 12 also stops.

Furthermore, when the loading platform 7 tilts, the rotating roller 18A of the link 14 is completely separated from the fixed base 20 and becomes irrelevant to the opening and closing of the sliding door 9.

In this way, since the top-opening sliding door 9 maintains almost the same plane as the loading platform 7, the rear opening becomes wide, and there is no problem in ejecting large loaded items, and the rear end of the loading platform 7 Loaded objects can be discharged to a more distant position.

Next, as the loading platform 7 returns to the horizontal state again around the loading platform support shaft 21, the rotary roller 18A begins to come into contact with the fixed base 20 again, and the sliding door drive shaft 11 rotates in the direction of arrow A. move.

This rotation causes the lever 16 to move in the direction of arrow B, and the lower hinge shaft 17 begins to rotate in the direction of arrow C.

Further, when the loading platform 7 returns to a completely horizontal state, the sliding door 9 closes the rear opening of the loading platform 7 and maintains this state.

In addition, if the inclination angle of the loading platform 7 is less than about 10 degrees, the sliding door 9
The link mechanism 12 and the fixed base 20 are adjusted so that the opening and closing operations are performed and the link mechanism 12 and the fixed base 20 are completely opened when the angle is about 10 degrees or more.

As explained above, according to the present invention, the link mechanism and the fixed base engage with each other as the loading platform tilts, and the automatic sliding door opens to almost the same plane as the surface of the loading platform. By providing the opening/closing means, the opening/closing operation is reliable, large loaded objects can be easily discharged, and damage to the loading platform is prevented, so the effect is extremely large.

[Brief explanation of drawings]

FIG. 1 shows a schematic configuration diagram of a conventional loading platform, A is a loaded state, B is a discharged state, and FIG. 2 is a schematic diagram of an embodiment of the present invention, A is a front view in a horizontal state, B is also a plan view, and FIG. 3 is a schematic diagram of the tilting state of the present invention in FIG. 2. 7... Loading platform, 8... Main girder, 9...
・・Side door, 10・・・Side door holder, 11・・・・
... Swing door drive shaft, 12 ... Sunku 4M, 13
, 14 , 15... Link, 16... Lever 17... Lower hinge shaft, 18...
Tip part, 20... Fixed base, 21... Loading platform support shaft.

Claims (1)

[Scope of utility model registration request] In a vehicle in which a loading platform 7 mounted on a truck frame is tiltably supported by a loading platform support shaft 21, a fan door 9 is provided at the rear opening of the loading platform and is pivotably supported by a lower hinge shaft 17 so as to be openable and closable. and a sliding door drive shaft 1 provided on the loading platform.
1, a second link 14 fixed to the sliding door drive shaft at a predetermined angle with the first link and having a support portion 18 at its tip, and a second link 14 fixed to the lower hinge shaft to drive the sliding door. It includes a link mechanism 12 consisting of a third link 15 that rotates and a lever 16 that connects the first and third links, and a fixing base 20 that is fixed to the truck frame and corresponds to the support part of the second link. When the loading platform is tilted, the supporting portion of the second link contacts the fixed base to rotate the sliding door in the direction of closing the sliding door, or separates from the supporting portion of the second link to rotate the sliding door in the opening direction. A rear fan door opening/closing device characterized by: