JPH11180153A - Device for jumping up carriage door of van type truck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow the carriage door to be softly shut by acting an biasing force against a shaft while pivotally rotating and extending with respect to the carriage together with a carriage pivot member in response to the stroke and pivotal rotation of the shaft, so reducing the rotational speed of an arm as it pivotally rotates to the side where the carriage door is shut. SOLUTION: When pressing up the door 2, an arm A52 pivotally rotates clockwise, and an arm B53, a rod 54 and a shaft 55 rotate counterclockwise. As the shaft 55 pivotally rotates, a compression spring 56 and a cover assembly 34 pivotally mounted to the roof side pivotally rotate around a pin 34e. As the shaft 55 shifts to the left, the energy stored in the compression spring 56 is diminished, serving as the force to open the rear door. As a result, the door can be opened lightly. It can be lightly closed in the reverse manner as mentioned above. As the force is applied to the shaft 55 and the compression spring 56 always in the axial direction, further strong force cannot be unnecessarily exerted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for flipping up a packing box door of a van type truck, and more particularly, to opening and closing the packing box by rotating the packing door about the upper side (horizontal axis) of the rear part of the packing box as a rotation axis. The present invention relates to a so-called flip-up type door opening and closing device.

[0002]

2. Description of the Related Art The inventors of the present invention have previously filed a filing apparatus for a van-type truck (see FIG. 1) (International Publication No. WO97 / 03854). This publication discloses an arm A having one end pivotally attached to a packing box door, an arm B having one end pivotally attached to the arm A and the other end pivotally attached to the packing box roof, and an arc-shaped one end pivotally connected to an intermediate portion of the arm B. By providing a rod, a shaft having one end attached to the other end of the rod, and a coil spring resiliently mounted between the other end of the shaft and a cover assembly pivotally attached to the packing box roof, A device that facilitates opening and closing operations is disclosed. This device is
In the door opening process, the cargo box door is manually pushed up to a predetermined intermediate position, and thereafter, the cargo box door is set up by itself by the urging force of the spring member. Conversely, in the door closing process, a string or the like attached to the packing box door is manually pulled to at least the intermediate position, and thereafter the door can be closed by itself.

[0003]

When the operating force for closing the packing box door is too large, the present inventors apply a large acceleration to the packing box door after the intermediate position due to inertia force, and the packing box door vigorously. We found that there was a usability hindrance of closing.

[0004] It is an object of the present invention to provide an easy-to-use van type truck packing box lifting device in which the packing box door closes quietly.

[0005]

The present invention includes the following elements in a first aspect. Arm A with one end pivotally connected to the packing box door. An arm B having one end pivotally connected to the packing box and the other end pivotally connected to the other end of the arm A. A rod having one end pivotally connected to an intermediate portion of the arm B and strokes and rotates with respect to the packing box in accordance with the rotation of the arm B. A shaft having one end attached to the other end of the rod, which strokes and rotates with respect to the packing box in accordance with the rotation of the rod. It is mounted between the other end of the shaft and a member pivotally attached to the packing box (hereinafter, referred to as a "packing box attachment member"), and together with the packing box attachment member according to the stroke and rotation of the shaft. A spring member that expands and contracts while rotating with respect to the packing box to apply an urging force to the shaft. Speed control means attached between the intermediate portion of the arm B and the cargo box pivoting member, wherein the speed control means reduces the rotational speed of the arm B when at least the arm B rotates to the cargo box door closing side. The speed control means is a member that is indirectly connected to the door and that strokes and turns in response to the door turning.
(a) and a member (b) that expands and contracts in accordance with the stroke of the member (a) to generate a door opening / closing assisting force rotate integrally, and the stroke direction of the member (a) and the member (b) ) Is suitably applied to a mechanism in which the direction of expansion and contraction is always coaxial.

[0006] The present invention includes the following elements in a second aspect. The speed control means rotates the packing box door at a position closer to the closing side of the packing door than a point where the force acting in the opening direction of the packing door and the force acting in the closing direction are balanced (hereinafter referred to as “dead center”). It produces a torque acting in the opposite direction to the direction. According to the second aspect, the rotation speed of the door is suppressed in the rotation region where acceleration due to the weight of the door occurs.
The present invention includes the following elements in a third aspect. The speed control means generates a torque acting in the opposite direction to the rotation direction of the packing box door before the dead center in the packing box door opening process and after the dead center in the packing box door closing process. According to the third viewpoint, the safety of the operation is improved in the rotation area where manual operation force is required. The present invention includes the following elements in a fourth aspect. The speed control means has a stroke member that strokes according to the rotation of the arm B. The speed control means has a resistance means for applying a resistance to the stroke of the stroke member. According to a fourth aspect, in a predetermined rotation area, the resistance means reduces the stroke speed of the stroke member, thereby connecting the arm B to the arm B via the arm A via the rotation speed. The rotation speed of the door is reduced. Such a stroke member and the resistance means can be accommodated in a cargo box pivoting member (preferably, a cover assembly accommodating a spring member), so that the outer dimensions of the van-type truck are not increased, and the street tree In such a case, the possibility that the flip-up device comes into contact is reduced.

[0007] The fifth aspect of the present invention includes the following elements. The packing box pivot member is a cover assembly that covers the rod, the shaft and the spring member, and is pivotally attached to the packing box at the other end of the shaft. The other end of the arm B is bifurcated, and each bifurcated portion is pivotally attached to a packing box. The rod is inserted into the space between the two forks of the arm B, and one end of the insertion portion is pivotally connected to an intermediate portion of the arm B. The speed control means
It extends between the cover assembly and the fork of the arm B, rod, shaft and spring member. According to a fifth perspective,
Since the cargo box pivoting member also serves as a protection member (rain and wind protection cover) such as a spring member, the number of parts can be reduced, and the structure becomes compact. Further, by providing a space between the loading box pivot points of the arms B and inserting the rod into this space, a linear rod can be used, which is advantageous in cost.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described. The packing door flipping device according to the invention reduces the speed of the packing door at least before closing the door. Further, the speed control means may be configured to operate in both the door opening stroke and the closing stroke to reduce the speed of the packing box door. Alternatively, the speed is adjusted so as to exert a resisting force in the direction of rotation of the packing box door before the dead center in the door opening stroke and after the dead center in the door closing stroke, that is, in a range requiring manual operation force. It is also preferable to configure control means. As a result, the usability (safety) in an area requiring manual operation is selectively improved.

As the speed control means, a one-way control means which operates at least immediately before the door is closed is used. However, as described above, a control means which operates in a two-way manner or in multiple stages may be used. For example, as a two-way means, means that gives a predetermined resistance to the operator in the initial area of the door opening stroke (before the dead center) and that operates as a brake in the latter part of the door closing stroke (after the dead center) can be used.

As the resistance force (resistance means) acting on the door via the arm B by the speed control means, one or more of hydraulic pressure, pneumatic pressure, elastic force, frictional force, electromagnetic force and the like can be used. For example, as the speed control means, one having an oil chamber or a spring (resistance means) and a piston rod (stroke means) connected to the spring can be used, or the piston rod (stroke means) strokes to one side. In such a case, a type in which the oil chamber (resistance means) is enlarged and the stroke of the oil chamber is reduced when a stroke is made to the other side (a resistance force is generated by an increase in hydraulic pressure) may be used.

In the embodiment described later, a compression spring is used as an auxiliary power source of the flip-up device, but a tension spring may be used instead. Further, although the coil spring is used in the embodiment, a spring having another shape can be used. Further, by setting the other end of the shaft (the side opposite to the rod connection point) as a free end, the load applied to the shaft is preferably reduced. By setting the center of rotation of the rod, shaft and spring member at the same point (the pivot point of the cargo box pivot member), they rotate integrally, so that the load is dispersed. Furthermore, in the device according to the present invention, it is not necessary to secure a space for the shaft to rotate inside the spring member, so that a spring member having a small inner diameter can be used, and the auxiliary power mechanism including the spring member can be used. The height of the (bouncer) can be reduced, and the structure becomes compact. In addition, since the cargo box pivoting member is a member that covers the spring member, the function of protecting the spring member and the like is also used, so that the number of parts can be reduced and the structure can be made compact. Torque can be transmitted from the shaft to the packing box pivoting member via a shaft, a spring receiving member fixed to the shaft, a peripheral surface of the spring member, or the like.

[0012] Further, one end of the arm B is bifurcated, the ends of these bifurcations are pivotally connected to the packing box side, and a space is provided between these pivot points so that the rod can be pivotally connected. Since it is possible to pass between the points and reach the middle part of the arm B (the pivot point of the rod), a straight rod can be used. Further, since the rod extends linearly between the arms B, the mounting position of the rod decreases, and the rod and the cargo box pivoting member (cover assembly)
Clearance can be increased. As a result, the space for mounting the speed control means, one end of which is attached to the arm B and the other end of which is attached to the cargo box pivoting member, is enlarged, and attachment becomes easy. Preferably, the speed control means is attached to each side of the cover assembly covering the spring member,
One may be attached to the central part, or three or more may be used.

Further, since the door flipping device according to the present invention can be attached to the outside of the packing box, there is an advantage that the packing box volume is substantially enlarged without obstructing the loading / unloading of the load. . For this reason, this apparatus is suitably applied to a cargo box door of a van type truck, but can also be applied to another door flip-up apparatus. In addition, one or a plurality of flip-up devices can be mounted according to the size and weight of the door. In the following embodiment, an example in which the door flip-up device is applied to the rear door of the van type truck has been described. However, the present invention is not limited to the rear door flip-up device of the van type truck. Side doors, front doors, as well as other flip-up doors,
It is apparent that the present invention can be suitably applied to other doors.

[0014]

An embodiment of the present invention will be described below with reference to the drawings. First, with reference to FIGS. 2 to 5, the basic configuration of a packing box flip-up device according to an embodiment of the present invention will be described.
The cargo box door flipping device shown in FIG.
Arm B53, rod 54, shaft 55, compression spring 5
6. Spring cover mounting structure 31, door opening adjustment mechanism 41
It is roughly constituted from.

Referring to FIGS. 2 to 5, one end of a vertically extending arm A52 is pivotally connected to the outer side of the rear packing box door 2 via a pin 57. One end of the arm B53 extending in the vertical direction and the horizontal direction is connected to a metal fitting 58 attached to the base plate 32 fixed to the roof of the packing box 1,
It is pivotally connected via a pin 59. The other ends of the arms A52 and B53 are pivotally connected to each other via a pin 60. One end of an arc-shaped rod 54 is pivotally connected to an intermediate portion of the arm B53 via a pin 61. The pivot point 61 of the rod 54 is the same as the rod pivot point 61 and the arm B53.
And the line connecting the rod pivot 61 and the mutual pivot 60 of the arms A and B is at a position substantially perpendicular to the line. The other end of the rod 54 has a door opening adjustment mechanism 41
Is attached to one end of the shaft 55. Note that the rod 54 and the shaft 55 operate integrally.

A cover mounting structure 31 is provided on the roof of the packing box 1.
Are arranged. The cover mounting structure 31 includes a base plate 32 fixed to the roof of the packing box 1 with bolts or the like,
A fixed side member such as a fixing bracket 33 fixed to the base plate 32 and a movable side member such as a cover assembly 34 (package box pivoting member) pivotally attached to the roof and incorporating a compression spring 56 and the like. I have. In the fixed member, the base plate 32 has a channel shape and is fixed to the roof of the packing box 1 by bolts 35 near the rear part of the packing box 1. In the range indicated by the mark * in FIG. 4, the roof of the packing box 1 is doubled as shown in the figure. Therefore, if the packing box 1 is installed in this range, there is no risk of leaking from the bolt holes to the inside of the packing box 1. . A fixing bracket 33 is fixed to the other end (the roof center side) of the base plate 32. Subsequently, on the movable side member of the cover attachment structure 31, the cover assembly 34 is pivotally attached to the key-shaped protrusion of the fixing bracket 33 via the pin 34e. The cover assembly 34 includes a channel-shaped main body cover 34a and a spring cover 34 fitted on the inner peripheral portion thereof.
b and the connecting member 34c. Both 34
A and 34b are integrally connected by a connecting member 34c and a bolt 34d (see FIG. 3B).

A shaft 55 whose one end is fixed to a rod 54 is inserted through the inside of the spring cover 34b. A spring receiver 62 is attached to the other end of the shaft 55 by a nut 55a. Also, the above-described spring cover 3
One end of 4b (fixed point side of rod 54 and shaft 55)
, A spring receiver 35 is attached. And both spring supports 6
A compression spring 56 is elastically mounted between 2 and 35. The initial compression amount of the compression spring 56 can be adjusted by the nut 55a,
This initial compression amount is adjusted so that the compression spring 56 is always in a compressed state, and the rear door 2 is supported at an arbitrary position by its elastic force.

Referring to FIGS. 5A to 5E, a description will be given of the door opening adjustment mechanism 41 as viewed by the arrow Q in FIG. The door opening adjustment mechanism 41 is mounted between the rod 54 and the shaft 55, and mainly includes a bracket 42 and an adjustment disk 43. The bracket 42 is formed of a plate having an L-shaped cross section. A through-hole 42b is formed in one surface of the bracket 42, and a bolt 42a is inserted through the elongated hole 42b and the hole provided in the rod 54. By tightening, the bracket 42 and the rod 54 are fixed so that their mutual positions can be changed. On the other surface of the bracket 42, a claw 42c is provided. The adjusting disk 43 has a disk shape, on one surface of which a cushioning material 43a is formed, and on the other surface, a plurality of (six in the drawing) radial grooves 43b are provided. I have. The claw 42c of the bracket is engaged with the groove 43b. In the center of the adjusting disk 43, a screw hole 43 is provided.
c has been processed. A female screw 55b provided at the end of the shaft 55 is screwed into the screw hole 43c.

The adjustment of the door opening is performed by a door opening adjusting mechanism 41.
Is performed as described below. That is, adjustment disk 4
3 is rotated to adjust the relative position between the shaft 55 and the adjustment disk 43, and then the claw 42c of the bracket is engaged with the groove 43b, and the relative position between the bracket 42 and the rod 54 is adjusted by the elongated hole 42b and the bolt 42a. I do. By adjusting the screwing position of the adjusting disk 43 to the shaft 55 and the mounting position of the bracket 42 to the rod 54 in this manner, the clearance between the end surface of the spring cover 34b and the cushioning material 43a is adjusted (FIG. 5 ( A)), the stroke of the shaft 55 in the axial direction, and the stroke of the rod 54 (movable amount in the axial direction of the shaft 55) are determined, whereby the rod 54, the arm B53, and the arm A52 can rotate. The amount is determined, and eventually arm A52
The opening of the rear door 2 (e.g., the maximum opening) is determined.

Next, the operation of the apparatus shown in FIG. 2 will be described. First, when the door 2 is manually pushed up from the state of FIG. 2 (the door 2 turns left in the figure), the arm A52 turns right, and the arm B53, the rod 54, and the shaft 55 turn left (see FIG. 4). ). Then, in response to the rotation of the shaft 55, the compression spring 56 and the cover assembly 34 pivotally attached to the roof similarly rotate about the pin 34e. Then, since the shaft 55 moves to the left in the figure, the energy stored in the compression spring 56 decreases and acts as a force for opening the rear door 2, so that the door can be opened lightly. On the contrary, when the open rear door 2 is closed, it can be closed lightly. Thus, the shaft 55 and the compression spring 56
Since force always acts along the axial direction (spring axis direction)
No excessive force is applied to them. Further, since the shaft 55 and the compression spring 56 rotate integrally, a spring having a small inner diameter can be used.

Further, at all the opening degrees of the rear door 2, the energy of the position with respect to the fully closed position of the door and the energy lost from the compression spring 56 (the energy of the lost position and the energy stored in the compression spring are newly stored). Energy)
If there is a perfect match, the door can be opened and closed with just enough force to overcome the frictional forces of the moving parts, and the door can be stationary at all degrees of opening. This is realized by adjusting the initial compression amount of the door opening adjustment mechanism 41 and the compression spring 56 described above.

Next, with reference to FIGS. 6 to 9, a door flipping device according to an embodiment of the present invention having a speed control means of the arm B in addition to the basic configuration described above will be described. Referring to FIG. 6, this improved device has one end attached to the bent portion of the arm B53 (slightly from the pivot point of the rod 54 to the pivot point 59 of the arm B53), and the other end to the cover assembly 34. Is provided with a speed control means 70 attached to the vehicle. Hereinafter, the structure of this device will be described in detail, particularly with respect to differences from the device shown in FIG. In FIGS. 6 to 9, the main body cover is omitted from illustration, but the present apparatus is also provided with the main body cover 34a similarly to the apparatus in FIG. 2 (see FIG. 3B).

In the apparatus of this embodiment, the arm B53
The roof-side extending portion is divided into two forks, and each forked portion is pivotally attached to a metal fitting 58 individually fixed to the base plate 32 via a pin 59. The linear rod 54 is
The arm B53 extends through a space between the two pivot points 59, 59, and has one end pivotally connected to a bent portion (intermediate portion) of the arm B53. The other end of the rod 54 is attached to the shaft 55 via the door opening adjustment mechanism 41. Then, the two speed control means 70 move the main body cover 3 above the rod 54 and the shaft 55.
4a, the outer peripheral portion of the outer tube portion and the outer side of the fork of the arm B53, the rod 54, the door opening adjustment mechanism 41, the shaft 55,
It extends between the spring cover 34b. Each of the two speed control means 70 has one end thereof bent slightly from the bent portion of the arm B53 (the arm B53 slightly from the pivot point 61 of the rod 54).
At the pivot point 59 side of the camera) via a pin 71. More specifically, it is attached to both ends of the pin 71 outside the pivot point 61 of the rod 54. The other ends of the two speed control means 70 are attached to pins 72 which bridge the other end between the main body cover 34a and the connecting member 34c (the member connecting the main body cover 34a and the spring cover 34b). . In the door opening adjustment mechanism 41 of this embodiment, the mutual attachment position of the rod 54 and the shaft 55 can be adjusted by adjusting the tightening position of the bolt 42a. In addition, a middle portion of the arm A52 is a turn buckle, so that the length of the arm A52 and the door opening can be adjusted.

In this embodiment, the speed control means 7
As 0, substantially no resistance is generated in the door opening stroke, but substantial resistance is generated in the door closing stroke, especially after the dead center, and the rod speed is reduced. As such speed control means, one end is attached to the cover assembly 34 side via a pin 72 and the other end is fixed to a piston, with one end attached to the arm B53 near the bent portion of the arm B53 via a pin 71. A piston rod, first and second oil chambers defined by the piston, an orifice formed in the piston to allow communication between the first oil chamber and the second oil chamber, and a first oil chamber side. A valve element that increases the opening of the orifice when the piston rod relatively strokes toward the second oil chamber, and decreases the opening of the orifice when it strokes to the opposite side (for example, the opening of the orifice when the valve is closed). With small holes that can communicate with each other)
And a valve having the following. In such a speed control means, a cylinder, a piston, and a piston rod constitute a stroke member, and an oil chamber,
Orifices and valves constitute resistance means.

Next, the operation characteristics of the device having the basic configuration shown in FIG. 2 and the device according to this embodiment shown in FIG. 6 will be described in comparison. Curves in FIG. 10 (showing the device characteristics in FIG. 2) and FIG. 11 show device characteristics in FIG. 6) represent the torque (operating force) acting on the door at each door opening, and each door opening. Corresponds to the torque required to stop the door. The larger the absolute value of the torque, the higher the door rotation speed. If an area requiring manual operation force is defined as − and an unnecessary area is defined as +, the + and − areas are switched between the opening stroke and the closing stroke. According to these figures, a manual force is required at the beginning of the door opening process, but is unnecessary after passing through the dead center (point of zero operating force). On the other hand, a manual force is required at the beginning of the door closing process. However, it is understood that the force is unnecessary after passing through the dead center (point of zero operating force). FIG. 8 shows a state of the dead center, and FIG. 9 shows a state in which the packing box door is fully opened. The functions of the spring member 56 and the like are the same as those of the device having the basic configuration described above, and the basic operation of the device of the present embodiment is the same as that of the device having the basic configuration.

Referring to FIG. 10, according to the apparatus having the basic configuration of FIG. 2, the operating force curves in the door opening stroke and the closing stroke are the same, and are the same as the torque required for opening the door. It can be seen that the torque (due to the biasing force of the spring member and its own weight) is applied when the door is closed. Therefore,
If the operation force for closing the door is too large, a large acceleration is applied to the packing box door after the dead point due to the inertial force, and the packing box door closes vigorously.

On the other hand, referring to FIG. 11, according to the improved apparatus of the embodiment shown in FIG. 6, there is a hysteresis in the torque curve in the door opening / closing stroke. That is, this device operates in the same manner as the device of the basic configuration in the door opening stroke, but in the door closing stroke, the speed control means exerts a resistance acting in the direction opposite to the door closing direction, so that the door is closed. The applied torque decreases (in the closing stroke, the torque indicated by the dotted line in FIG. 11 is lower than the torque indicated by the solid line in FIG. 10). Therefore, even if the door is pressed down by a relatively large force, the torque applied to the door is reduced by the resistance of the speed control means transmitted to the door via the arm B or the like, and the rotation speed of the door is reduced.
In particular, since the torque is greatly reduced in the door closing stroke after the dead center, the door closes quietly.

The embodiment of the present invention can incorporate the mechanism of the device described with reference to FIGS. Further, in this embodiment, the speed control means can be mounted between the main body cover 34a and the spring cover 34b, or between the spring cover 34b and the connecting member 34c (see FIG. 3B). It should be noted that the present invention is not limited to the above-described embodiment, and furthermore, a person skilled in the art can make obvious changes based on the basic idea and principle of the present invention derived from the entire disclosure of the present invention. it can. Furthermore, the present invention does not exclude altering, amending, or dividing as required at the time of filing the application based on the entire disclosure.

[0029]

According to the present invention, even when the closing operation of the packing box door is performed with a predetermined operating force or more, the packing box door is closed quietly. Provided. Further, according to the present invention, since no excessive force is applied to the spring member and the spring member and the like are installed on the roof of the packing box, there is no hindrance to the work of carrying in / out the load. Further, by providing the door opening adjustment mechanism according to the present invention, the door can be stopped at a predetermined position. Furthermore, the device according to the invention can be fitted entirely on the roof (outside the packing box), so that leakage into the packing box is prevented.

[Brief description of the drawings]

FIG. 1 is a view showing a van-type truck.

FIG. 2 is a side view for explaining a basic configuration of a door flip-up device according to one embodiment of the present invention.

FIGS. 3A to 3E are views for explaining details of the apparatus shown in FIG. 2; FIG. 3A is a right side view of FIG. 2;
(B) is an arrow view of the DD section in FIG. 2, and (C) is A in FIG. 2.
2A is an arrow view of a cross section, FIG. 2D is an arrow view of a BB section in FIG. 2, and FIG. 2E is an arrow view of a CC section in FIG.

FIG. 4A is an operation diagram of the device shown in FIG. 2;
(B) is an arrow view of an EE section in (A), and (C) is an arrow view of an FF section in (A).

FIG. 5 is a view showing a door opening adjustment mechanism applied to the apparatus according to one embodiment of the present invention, wherein (A) is an arrow Q in FIG. 4;
FIG. 4B is a detailed enlarged view of the portion, FIG. 4B is a bottom view, FIG. 4C is a right side view, FIG. 4D is a view showing the bracket, and FIG.

FIG. 6 is a side view illustrating a door flip-up device according to an embodiment of the present invention.

FIG. 7 is a plan view of FIG. 6;

FIG. 8 is an operation diagram of the apparatus shown in FIG. 6, showing a state where a packing box door is at a dead center position.

FIG. 9 is an operation diagram of the apparatus shown in FIG. 6, showing a state in which the packing box door is opened to the maximum.

FIG. 10 is a diagram for explaining characteristics of the device shown in FIG. 2;

11 is a diagram for explaining characteristics of the device shown in FIG.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 packing box 2 rear door 31 spring cover mounting structure 32 base plate 33 fixing bracket 34 cover assembly (packing box pivoting member) 34a body cover 34b spring cover 34c connecting member 34d, 42a bolt 35, 62 spring support 41 door opening degree Adjusting mechanism 42 Bracket 42b Long hole 42c Claw 43 Adjusting disk 43a Buffer material 43b Groove 43c Screw hole 51 Lifting device for rear door of van type truck 52 Arm A 53 Arm B 54 Rod 55 Shaft 55a Nut 55b Female screw 56 Compression spring 58 Metal fitting 34e , 57, 59, 60, 61, 70, 71 pins (pivot point) 70 Speed control means

Claims (5)

[Claims] 1. A van type truck having a packing box and a packing box door which is opened and closed by rotating about a horizontal axis, wherein an arm A having one end pivotally connected to the packing box door and one end connecting to the packing box. An arm B pivotally connected and the other end pivotally connected to the other end of the arm A; one end pivotally connected to an intermediate portion of the arm B, and a stroke with respect to the packing box according to the rotation of the arm B A rotating rod, one end of which is attached to the other end of the rod, a shaft that strokes and rotates with respect to the packing box according to the rotation of the rod, and another end of the shaft. The cargo box is elastically mounted between a member pivotally mounted on the packing box (hereinafter, referred to as a “packing box mounting member”), and the loading box together with the packing box mounting member according to the stroke and rotation of the shaft. A spring member that expands and contracts while rotating with respect to the box to apply a biasing force to the shaft; Speed control means attached between the middle portion of the arm B and the cargo box pivoting member, the speed control means decreasing the rotational speed of the arm B when at least the arm B rotates to the cargo box door closing side; A cargo box door flip-up device for a van-type truck, comprising: 2. The carton door rotation position on the closing side of a point (hereinafter referred to as "dead point") in which the force acting in the opening direction of the carton door and the force acting in the closing direction are balanced. 2. The apparatus according to claim 1, wherein the apparatus generates a torque acting in a direction opposite to the direction of rotation of the packing box door. 3. The speed control means according to claim 1, further comprising: a torque acting in a direction opposite to a rotating direction of the packing box door before the dead point in the opening step of the packing box door and after the dead point in the closing step of the packing box door. 2. The device according to claim 1, wherein the door is raised. 4. The apparatus according to claim 1, wherein the speed control means includes a stroke member that strokes in accordance with the rotation of the arm B, and resistance means that acts on the stroke of the stroke member. 4. A device for lifting a carton door of a van type truck according to claim 1. 5. A cover assembly for covering the rod, the shaft, and the spring member, wherein the cargo box pivot member is a cover assembly.
The other end of the shaft is pivotally attached to the packing box, the other end of the arm B is divided into two branches, and the two forks are respectively pivotally attached to the packing box. One end of the insertion portion is pivotally connected to an intermediate portion of the arm B, and the speed control means comprises: the cover assembly; 5. The apparatus according to claim 1, wherein the apparatus extends between the rod, the shaft, and the spring member. 6.