JP5517703B2 - Fall prevention stopper for floor plate such as tailgate - Google Patents

Description

  The present invention relates to a fall prevention stopper mounted on a floor plate (platform) in a tailgate or the like equipped on a rear part or a side part of a truck or the like for loading and unloading cargo on a loading platform such as a truck.

  Truck loading platforms, which are vehicles for freight transportation, include an uncovered loading platform that opens upward, a hexahedral box-shaped loading platform that has a roof and is hermetically sealed. In recent years, box-type loading platforms, that is, van bodies, that can prevent damage to cargo due to wind and rain, simplify packaging, and easily prevent load slippage, that is, van bodies, have become widespread. Since these loading platforms are mounted on the chassis frame of the truck consisting of wheels, main rails, suspension mechanisms, etc., there is a considerable difference in height between the loading platform floor and the ground, which hinders loading and unloading of cargo. It becomes.

  The tailgate is well known as a lifting device that raises and lowers the cargo between the ground and the loading platform floor to improve the workability in loading and unloading work and reduce the burden on the operator. It has been. The tailgate is usually attached to the rear end portion of the truck, and is provided with a parallel link mechanism for raising and lowering the cargo while keeping it in a horizontal state in order to prevent the cargo or the like on the floor plate from falling. There is a case where the tailgate is installed on the side surface of the vehicle, and there is also a lifting device that supports the floor plate so as to be slidable on a vertical support and moves up and down horizontally between the ground surface and the loading platform floor surface.

  When loading and unloading cargo onto the loading platform using a tailgate, a cargo cart with wheels (casters) is often used to load the cargo on the floor plate in order to facilitate the work. . At the tip of the floor plate of the tailgate, a fall prevention stopper is mounted, which serves as a wheel stopper for a wheeled cargo truck mounted on the floor plate, and is called a roll stopper.

The outline of the tailgate having the floor plate and the fall prevention stopper installed at the tip of the floor plate will be described with reference to FIGS.
As the tailgate, one that stores the floor plate in a state of leaning against the rear end of the loading platform is widely used, but one that stores the folding floor plate under the floor at the rear portion of the loading platform is also widely used. The tailgate shown in FIG. 4 is a tailgate stored under the rear floor of the rear wheel RW of the vehicle. The tailgate including the foldable floor plate 1 and the parallel link mechanism 2 is entirely supported by the vehicle support chassis 3. A guide rail 4 fixed to a main rail MR constituting the frame is slidably attached. Floor plate 1 is provided with a main plate 11 and the sub plate 12 coupled with a double hinge, the storage state, the sub-plate 12 is folded on the upper surface of the main plate 11, the guide rail 4 by sliding hydraulic cylinder (not shown) It is located in the storage position of the front end portion of the.

  When the tailgate is used for loading and unloading cargo, the slide hydraulic cylinder is extended so that the support substrate 3 is positioned at the pull-out position of the rear end portion of the guide rail 4 as shown in FIG. . At the pull-out position, the floor plate 1 is lowered by a lifting hydraulic cylinder (not shown) connected to the parallel link mechanism 2, and after landing, the folded floor plate 1 is unfolded and the upper surfaces of the main plate 11 and the sub plate 12 are Make a continuous plane. Further, the main plate 11 is rotated and tilted, and the tip of the sub-plate 12 is grounded as shown in FIG. As an example, the underfloor retractable tailgate that performs such an operation is disclosed in Japanese Patent No. 3409939.

In order to load cargo onto the loading platform using the wheeled cargo cart, the cargo cart DL is placed on the floor plate 1 in the state shown in FIG. A drop prevention stopper 5 that can be switched between a standing position and a flat position is attached to the tip of the sub-plate 12. When the cargo cart DL is placed, the fall prevention stopper 5 is raised as shown in the figure. As a position, it hits the wheel of the cargo carriage DL. Then, the parallel link mechanism 2 is actuated by the lifting hydraulic cylinder to raise the floor plate 1 to the level of the loading platform floor as it is, as shown in FIG. During this time, the fall prevention stopper 5 keeps the standing position and prevents the cargo carriage DL from moving or dropping.
Conversely, when unloading cargo from the loading platform of the vehicle, the floor plate 1 is lowered and brought into contact with the wheels of the cargo cart DL in contact with the fall prevention stopper 5 at the standing position. Next, when the floor plate 1 is tilted to bring the cargo carriage DL into the state shown in FIG. 5B, the fall prevention stopper 5 is stepped on with a foot to switch to the flat position. Thus, the cargo cart DL can be moved to the ground while passing over the fall prevention stopper 5.

The structure of the tailgate fall prevention stopper 5 is disclosed in Japanese Patent Application Laid-Open No. 11-34721 as an example, and FIG. 6 shows the fall prevention stopper described in this publication.
FIG. 6A is a perspective view of a state in which the foldable floor plate 1 connected to the two sets of parallel link mechanisms 2 on the left and right sides is grounded and the main plate 11 and the sub plate 12 are developed from above. A drop prevention stopper 5 extending substantially across the entire width in the lateral direction is installed at the tip of the sub-plate 12, and the fall prevention stopper 5 is placed at a flat position at both side ends that do not hinder cargo handling work. A switching mechanism 5C for switching to the standing position is provided.

6B and 6C are cross-sectional views of the switching mechanism 5C, that is, a cross section taken along the line AA of FIG. 6A. FIG. 6B is a state where the fall prevention stopper 5 is in a flat position. c) represents a state in which the fall prevention stopper 5 is in an upright position.
The fall prevention stopper 5 is accommodated in the recess 5R at the tip of the sub-plate 12 at the flat position (b), and its surface forms a flat surface with the upper surface of the sub-plate 12. The fall prevention stopper 5 is pivotally attached to the end of the recess 5R so as to be rotatable about 5O, and is urged toward the standing position (c) by the linear spring 5S. A locking member 5X is fixed to the surface of the fall prevention stopper 5, and a lock member 5Y pivotally attached to the base portion 5B of the sub-plate 12 is provided at a position facing the rear end portion. In the flat position (b), the front end of the locking member 5Y comes into contact with the rear end of the locking member 5X to prevent the fall prevention stopper 5 from standing up and release the wheel stopper function.

  The lock member 5Y is connected to a handle or the like (not shown). When the tip of the lock member 5Y is rotated upward as shown in FIG. The stopper 5 becomes a standing position by the linear spring 5S, and a wheel stopper function is generated. If the fall prevention stopper 5 is stepped on in a state where the lock member 5Y is tilted forward in advance, the lock member 5Y automatically contacts the locking member 5X of the fall prevention stopper 5 as shown by the two-dot chain line in (c). In contact therewith, the fall prevention stopper 5 is locked in the flat position (b).

Japanese Patent No. 3409939 Japanese Patent Laid-Open No. 11-34721

  It is desirable that the fall prevention stopper installed on the tailgate extends over the entire width of the floor plate as much as possible in order to reliably prevent the cargo carriage from being located at any position in the lateral direction. The switching mechanism that switches the fall prevention stopper between the flat position and the standing position needs to be disposed at both end portions so as to be compact and easy to operate so as not to hinder the passage of the cargo cart. In the underfloor retractable tailgate that stores the floor plate under the floor, the height of the switching mechanism from the plate surface needs to be made compact so that the switching mechanism does not become an obstacle to folding.

Further, the switching mechanism for the fall prevention stopper must be surely held in a flat position or a standing position. For example, the switching mechanism shown in FIG. 6 is such that the tip of the locking member is brought into contact with the rear end of the locking member and the fall prevention stopper is held in a flat position. As a result, the engagement between the locking member and the locking member may be released, and the fall prevention stopper may be in an upright state.
An object of the present invention is to make the switching mechanism in the fall prevention stopper installed at the tip of the tailgate compact, and to enable easy and reliable holding of a flat position or the like.

In view of the above problems, the present invention forms a locking portion on the back surface of the fall prevention stopper, and a hook member that engages with the locking portion is provided in the switching mechanism, and the hook member is fixed to a rotating shaft having a handle. And a regulating member for controlling the engagement between the hook member and the locking portion. That is, the present invention
“Switching mechanism that switches the position of the fall prevention stopper pivotally attached to the tip of the cargo loading floor plate between the flat position and the standing position in the lifting device that lifts and lowers the cargo between the ground and the loading platform floor of the vehicle. Because
The fall prevention stopper is biased to an upright position by a spring, a locking portion is formed on the back surface of the fall prevention stopper, and the switching mechanism includes a hook member that engages with the locking portion. And
The hook member is fixed to a rotation shaft having a handle, is urged by a rotation spring to rotate in a direction to engage with the locking portion, and is attached by a push-up spring to move in the vertical direction. In addition,
The switching mechanism allows the hook member to rotate to engage with the locking portion when positioned below, and prevents the hook member from rotating to engage with the locking portion when positioned above. There is a regulating member. ''
The switching mechanism is characterized by this.

  According to a second aspect of the present invention, a restriction groove having a passage part that allows the hook member to rotate and a blocking part that prevents the rotation can be formed in the restriction member.

  According to a third aspect of the present invention, the hook member is formed with a slope contacting the back surface of the fall prevention stopper, and when the fall prevention stopper is lowered, the hook member automatically moves the locking portion. Can be engaged.

  As described in claim 4, the fall prevention stopper switching mechanism of the present invention is suitable for a foldable floor plate having a main plate and a sub plate.

  In the fall prevention stopper and its position switching mechanism of the present invention, a locking portion is formed on the back surface of the fall prevention stopper, and a hook member that engages with this is provided in the switching mechanism. Since the locking portion that engages with the hook member and holds the fall prevention stopper in a flat position is formed integrally with the back surface of the fall prevention stopper, parts for such a locking portion can be omitted. The number of parts is reduced and the structure is simplified at the same time. The hook member is fixed to a rotating shaft having a handle, and switches between a flat position and an upright position of the fall prevention stopper by rotating, and its size and movable range are very compact. Therefore, the switching mechanism of the present invention can be arranged in a narrow space beside the fall prevention stopper.

  The hook member and the locking portion of the present invention exist on the back surface of the fall prevention stopper and are not exposed on the surface of the floor plate. Therefore, there is less risk of cargo carts and cargo colliding and damaging during cargo handling operations, and the possibility of malfunction due to foreign objects such as stones being caught. In addition, since the handle fixed to the hook member is rotated or moved up and down to switch between the flat position and the standing position, the operation is easy. The hook member is biased by the rotation spring in the direction in which the hook member is engaged with the locking portion, and the hook member that holds the flat position does not come off even if vibration or the like acts.

  As in the second aspect of the invention, when the restriction groove having the passage portion allowing the rotation of the hook member and the blocking portion for preventing the rotation is formed in the restriction member, the hook member can be configured with a simple configuration. Control becomes possible. Further, as in the invention of claim 3, when the inclined surface that contacts the back surface of the fall prevention stopper is formed on the hook member, and when this is lowered, the hook member is automatically engaged with the locking portion, Switching operation between the flat position and the standing position becomes easy.

  The invention according to claim 4 applies the switching mechanism of the fall prevention stopper according to the present invention to a foldable floor plate having a main plate and a sub plate, such as an underfloor retractable tailgate. In such a floor plate, when the fall prevention stopper is folded in a flat position, it is necessary that the height dimension is small so that the switching mechanism does not come into contact with the floor plate. Is on the back of the fall prevention stopper and is basically low in height. And in the flat position of a fall prevention stopper, since a hook member and a handle | steering_wheel are in a downward position, height becomes still lower.

It is a figure which shows the fundamental action | operation in the switching mechanism of the fall prevention stopper of this invention. It is a figure which shows the detail of the switching mechanism of this invention. It is a perspective view of the control member of the switching mechanism of the present invention. It is a side view which shows the retracted state of the underfloor retractable tailgate. It is an operation | movement figure which shows the operation | movement of the tailgate which loaded the cargo trolley | bogie. It is a figure which shows the switching mechanism of the conventional fall prevention stopper.

  Hereinafter, an embodiment in which the fall prevention stopper switching mechanism according to the present invention is applied to an underfloor retractable tailgate will be described with reference to FIGS. 1 to 3. The basic structure of the tailgate is shown in FIGS. 6 is the same as the conventional structure shown in FIG. 6. In FIGS. 1 to 3, the same reference numerals are given to basic parts corresponding to the parts shown in FIGS.

FIG. 1 is a diagram showing a basic operation of the switching mechanism for the fall prevention stopper according to the present invention, and corresponds to the operation diagram of FIG. FIG. 1A shows a plan view of the end of the fall prevention stopper 5 and a sectional view of the switching mechanism 5C in a state where the fall prevention stopper is in a flat position, and FIG. The figures in the state are shown.
The fall prevention stopper 5 is pivotally attached to the recess 5R at the tip of the sub-plate 12 by a hinge 5H (the pivot axis center of the hinge 5H is indicated by 5HO), and is accommodated in the recess 5R at the flat position (a). The surface forms a flat surface with the upper surface of the sub-plate 12. A torsion coil spring (not shown) is mounted on the pivot shaft of the hinge 5H, and the fall prevention stopper 5 is urged to rotate around the pivot shaft to reach the standing position (b).

In the present invention, locking portions 51 are formed on the back surfaces of both end portions of the fall prevention stopper 5. The locking portion 51 is formed by forming a groove having a substantially U-shaped cross section over a predetermined length (including the entire width) from the side end face of the fall prevention stopper 5, and the fall prevention stopper 5 is in a flat position. Sometimes, the bottom of the locking portion 51 forms a horizontal plane. Then, at a position adjacent to the side end face of the fall prevention stopper 5, the switching mechanism 5 C for switching the fall prevention stopper 5 in the upright position and the flat position is located. This position is a portion corresponding to the lateral end of the sub-plate 12 . Incidentally, in order to prevent foreign material from entering the switching mechanism 5 C, a cover (not shown) so as to cover the upper surface is provided, I am possible to penetrate the handle 5C2 above the cover.

Detailed structure and operation of the switching mechanism 5 C, will be described also with reference to FIG. FIGS. 2 (a) corresponds to FIG. 1 (a), represents the state of the switching mechanism 5 C when the fall prevention stopper 5 in a flat position, corresponding to FIG. 2 (b), and FIG. 1 (b) to, fall prevention stopper 5 represents the state of the switching mechanism 5 C when in the standing position.
As shown in FIG. 2 (a) (b), the switching mechanism 5 C is provided with a hook member 5C1, when the anti-fall stopper 5 in a flat position, the hook member 5C1 of the rear surface of the fall prevention stopper 5 Engage with the locking portion 51 to prevent the fall prevention stopper 5 from rising (state shown in FIG. 1A). The hook member 5C1 is a plate-like member fixed to a rotating shaft 5C3 having a handle 5C2 and having a slope 5C11 formed at the tip. Lower part and the upper part of the rotation shaft 5C3 is supported in a through hole provided in the switching mechanism 5 C of the substrate 5C4 and upper support plate 5C5, also, an end portion of the hook member 5C1 by turning spring 5C6 is attached The hook member 5 </ b> C <b> 1 is biased to rotate in a direction to engage with the locking portion 51 of the fall prevention stopper 5. A push-up spring 5C7 surrounding the rotation shaft 5C3 is disposed between the hook member 5C1 and the substrate 5C4, and the hook member 5C1 is also biased upward.

Side switching mechanism 5 C, that is, between the side end face of the fall prevention stopper 5 and the pivot shaft 5C3, regulating member 5C8 is provided. As shown in FIG. 3, the regulating member 5C8 is a plate member that is erected by bending the substrate 5C4. The regulating member 5C8 includes a passage portion C8A that allows the hook member 5C1 to rotate, and prevents the rotation. A regulating groove 5C81 having a blocking portion C8B is formed.

  When the fall prevention stopper 5 is set to the flat position in FIG. 1A, the handle 5C2 is pushed down by an operation such as stepping on with a foot. As a result, the push-up spring 5C7 is compressed and the rotation shaft 5C3 and the hook member 5C1 are in the lower position. As shown in FIG. 2A, the hook member 5C1 is rotationally biased by the rotation spring 5C6. It passes through the passing portion C8A of the regulating member 5C8 and engages with the locking portion 51 on the back surface of the fall prevention stopper 5. Here, when the fall prevention stopper 5 is changed from the standing position to the flat position, if the tip of the fall prevention stopper 5 is pushed down by an operation such as stepping on with a foot, the side edge portion on the back surface of the fall prevention stopper 5 Comes into contact with the inclined surface 5C11 at the tip of the hook member 5C1, and the hook member 5C1 rotates a small amount in the reverse direction by the cam action of the inclined surface. When the fall prevention stopper 5 reaches the flat position while pushing away the hook member 5C1, the hook member 5C1 is urged by the rotating spring 5C6 and engages with the locking portion 51 to hold the fall prevention stopper 5 in the flat position. It will be.

  When the fall prevention stopper 5 is set to the standing position in FIG. 1B, the handle 5C2 is operated to the outside of the sub-plate so as to be in the position of the plan view in FIG. As a result, the hook member 5C1 rotates against the rotation spring 5C6, and the hook member 5C1 is detached from the locking portion 51 of the fall prevention stopper 5 and also from the passage portion C8A of the regulating member. The hook member 5C1 is moved upward by the push-up spring 5C7 and enters the blocking portion C8B of the restriction groove 5C81. Here, since the hook member 5C1 is prevented from rotating, the fall prevention stopper 5 is held in the standing position.

As described above in detail, in the present invention, a locking portion is formed on the back surface of the fall prevention stopper, a hook member that engages with the locking portion is provided in the switching mechanism, and the hook member is fixed to a rotating shaft having a handle. Thus, a urging force is applied by a rotating spring and a push-up spring, and a regulating member for controlling the engagement between the hook member and the locking portion is provided. Therefore, the switching mechanism in the tailgate fall prevention stopper is made compact, and the operation is easy and reliable.
In the above embodiment, the present invention is applied to an underfloor retractable tailgate having a foldable floor plate. However, the present invention is stored in a state where the floor plate is leaned against the rear end of the loading platform. Needless to say, it can be applied to tailgates. In the above embodiment, a tension spring is used to rotate the hook member. However, various modifications can be made to the embodiment, such as installing a torsion coil spring on the rotating shaft and rotating it. Obviously.

DESCRIPTION OF SYMBOLS 1 Floor plate 11 Main plate 12 Subplate 5 Fall prevention stopper 51 Locking part 5C Switching mechanism 5C1 Hook member 5C2 Handle 5C3 Rotating shaft 5C6 Rotating spring 5C7 Push-up spring 5C8 Restriction member 5H Hinge (of fall prevention stopper)

Claims (4)

In a lifting device that raises and lowers cargo between the ground and the loading platform floor of the vehicle, a switching mechanism that switches the position of the fall prevention stopper pivotally attached to the tip of the cargo loading floor plate between a flat position and a standing position There,
The fall prevention stopper is biased to an upright position by a spring, a locking portion is formed on the back surface of the fall prevention stopper, and the switching mechanism includes a hook member that engages with the locking portion. And
The hook member is fixed to a rotation shaft having a handle, is urged by a rotation spring to rotate in a direction to engage with the locking portion, and is attached by a push-up spring to move in the vertical direction. In addition,
The switching mechanism allows the hook member to rotate to engage with the locking portion when positioned below, and prevents the hook member from rotating to engage with the locking portion when positioned above. A switching mechanism characterized in that a regulating member is provided. The switching mechanism according to claim 1, wherein the restriction member is formed with a restriction groove having a passage part that allows the hook member to rotate and a blocking part that prevents the rotation. The slope of the hook member is formed on the back surface of the fall prevention stopper, and when the fall prevention stopper is lowered, the hook member automatically engages with the locking portion. Item 3. The switching mechanism according to Item 2. The switching mechanism according to any one of claims 1 to 3, wherein the floor plate includes a main plate and a sub plate and is configured to be foldable.

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