JP2002234446A - Carriage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lift/lower a wheel unit by raising/leveling a bottom plate. SOLUTION: The bottom plate 25 and the wheel unit 19 are interlocked with each other by a mechanical interlocking device 29. By means of the mechanical interlocking device 29, the wheel unit 19 is lifted and the tread face of a wheel 21 in the wheel unit 19 is positioned above the tread face (a height position (a) in the figure 3) of a wheel 14 in a swivel caster 10 when the bottom plate 26 is raised, and when the bottom plate 26 is leveled, the wheel unit 19 is lowered and the tread face of the wheel 21 in the wheel unit 19 is positioned below the tread face of the wheel 14 in the swivel caster 10 (positioned in a height position c in the figure 3).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a truck.

[0002]

2. Description of the Related Art Heretofore, the following types of bogies have been known. A bottom frame, which is long in the front-rear direction, is provided with swivel casters at four corners of the lower surface, and is provided with a wheel unit that does not rotate on the left and right lower surfaces of the middle part in the front-rear direction, which is vertically movable; A bottom plate provided to be able to swing up and down directly or indirectly at a rear portion, and a grounding surface of the wheel of the wheel unit, a bogie made to be able to come and go with respect to the grounding surface of the wheel of the turning caster,
It is known that the wheel unit is lowered by the fall of the bottom plate so that the contact surface of the wheel of the wheel unit is located below the contact surface of the wheel of the turning caster (Japanese Patent No. 3,096). 948).

[0003]

Disadvantages of the prior art The above-mentioned conventional truck has the following disadvantages. During nesting (storage by shifting the truck in the front-rear direction and keeping it close to the left and right), raise the wheel unit to raise the bottom unit and raise the wheel unit to make it easier for the truck to move in any direction. The contact surface of the wheels of the unit is located above the contact surface of the wheels of the swivel casters, but the work has to be performed manually, which is disadvantageous in that the work is troublesome.

[0004]

The present invention employs the following means to solve the above-mentioned drawbacks. The invention of claim 1 is characterized in that it is long in the front-rear direction,
A turning frame is provided at the corner, and a bottom frame is provided with a wheel unit that does not turn on the left and right lower surfaces of the middle part in the front-rear direction. The bottom frame is freely movable up and down directly or indirectly at the front or rear of the bottom frame. And a bottom plate provided in
The contact surface of the wheels of the wheel unit, in a bogie that is made to be able to come and go with respect to the contact surface of the wheels of the swivel casters, the bottom plate and the wheel unit are made to interlock by a mechanical interlock device, the mechanical interlock device, When the bottom plate rises, the wheel unit is raised and the grounding surface of the wheels of the wheel unit is positioned above the grounding surface of the wheels of the caster. The caster wheels are located below the ground contact surface. According to a second aspect of the present invention, the mechanical interlocking device is pivotally connected to a first rocking piece provided on a rocking base of the bottom plate by a pivot having an axis oriented in the left-right direction to the first rocking piece. A connecting rod having a longitudinal direction directed in the front-rear direction, a second rocking piece pivotally connected to the other end of the connecting rod by a pivot having an axial center directed in the left-right direction, and a second rocking piece. It has a rotating shaft that is rotatably provided on the bottom frame so that the base is fixed and the axis is oriented in the left-right direction, and a protruding piece that raises and lowers a vertically movable wheel unit provided on the rotating shaft. The wheel unit according to claim 1, wherein the wheel unit is biased upward by a biasing means such as a spring. The invention according to claim 3 is characterized in that the wheel unit is provided directly or indirectly on the bottom frame so as to be swingable up and down by a pivot whose axis is oriented in the left-right direction, and the protruding piece is mounted on the wheel unit while the bottom plate is lying down. 3. The apparatus according to claim 2, wherein the bottom plate further receives a rotational force in a direction in which the bottom plate falls down. The invention according to claim 4 is characterized in that the bottom frame has a hollow base material whose longitudinal direction is directed forward and backward, and a longitudinal direction in which a central portion is directly or indirectly provided at front and rear portions and an intermediate portion of the base material. 3. The vehicle according to claim 2, further comprising: three arm members extending in the left-right direction, wherein a swivel caster or a wheel unit is provided on the lower surface of the left or right end of the arm member, and the connecting rod is fitted to the base material. belongs to.

[0005]

According to the present invention, the following effects can be obtained by the above-described configuration. According to the first aspect of the present invention, the wheel unit can be lowered or raised by the mechanical interlocking device by the falling and standing of the bottom plate, so that the usability is extremely high. According to the second aspect of the present invention, there is little failure with a simple structure. According to the third aspect of the present invention, in the state where the bottom plate is laid down, the protruding piece receives the rotational force from the wheel unit in the direction in which the bottom plate is further laid down. (In the state where the force is applied), the protrusion does not rotate in the direction to raise the wheel unit, so that it is possible to prevent a trouble that the position of the wheel unit suddenly changes during use. According to the invention of claim 4, since the connecting rod is fitted in the hollow base material and the connecting rod is protected by the base material, it is possible to prevent the connecting rod from being damaged.

[0006]

Embodiments of the present invention will be described below. In this description, the front refers to the right side in FIG. 1, the rear refers to the left side in FIG. 1, the left refers to the back side of FIG. 1, and the right refers to the front side.

The bottom frame 2 of the trolley 1 is provided on a hollow base material 3 whose longitudinal direction is directed to the front and back, and below the front and rear portions and intermediate portions of the base material 3 as described in detail below. It has three arm members 4 and 5 whose longitudinal directions are oriented in the left-right direction.

The front and rear arm members 4 are attached to the ends of the base material 3 via hollow short struts 6 erected at the center in the left-right direction. As shown in FIG. 4, the front short strut 6 is provided on the left side with respect to the base material 3 so that the right end opening of the front end of the base material 3 is not closed by the short strut 6. Is provided so that a connecting rod 33 described later protrudes forward. Rear short strut 6
Also, like the short column 6 on the front side, it is provided to be offset to the left with respect to the base material 3.

The intermediate arm member 5 is attached to the base member 3 via a connecting plate 7, as shown in FIGS.

A frame 8 is erected on the front and rear short columns 6.

A well-known swivel caster 10 is provided on the lower surface of the left and right ends of the front and rear arm members 4. The swivel caster 10 includes a mounting plate 11 provided on the arm member 4, a bracket 13 provided on the mounting plate 11 so as to be rotatable around a vertical center line 12, and a rotation of the bracket 13 via a horizontal axis. And wheels 14 provided freely.

At the left and right ends of the intermediate arm member 5, there are provided rectangular parallelepiped supports 16 with open lower surfaces, and a wheel unit 19 is provided on these supports 16 via a pivot 17 whose axis is oriented in the left-right direction. The wheel unit 19 is urged upward by a known urging means (not shown) such as a spring (see an arrow L in FIG. 3). The wheel unit 19 includes a bracket 20 provided on the support 16 via a pivot 17 and wheels 21 rotatably provided on the bracket 20 via a horizontal axis.

As shown in FIG. 3 and FIG. 4, a rotary shaft 24 having an axial center in the left-right direction is provided on the front short support 6 so as to be rotatable at an intermediate portion in the horizontal direction.
, A bottom plate 26 is attached via a connecting piece 25.
With such a configuration, the bottom plate 26 swings up and down to be able to take a standing state and a falling state. When the bottom plate 26 falls down to a horizontal state, the bottom plate 26
Is in contact with the upper surface of the base material 3 and the upper surfaces of the arm members 4 and 5 so as not to swing downward beyond the horizontal state.

The bottom plate 26 and the wheel unit 19 are interlocked by a mechanical interlock device 29. The mechanical interlock device 29 raises the wheel unit 19 when the bottom plate 26 rises, and the wheels 21 of the wheel unit 19
Is positioned above the contact surface of the wheel 14 of the swivel caster 10 (see the height position "a" in FIG. 3) (see FIG. 3).
When the bottom plate 26 falls down, the wheel unit 19 is lowered and the contact surface of the wheel 21 of the wheel unit 19 is positioned below the contact surface of the wheel 14 of the swivel caster 10. (Located at the height position "c" in FIG. 3).

The mechanical connecting device 29 includes a bottom plate 26.
Of the first rocking piece 3 provided on the rocking base (rotary shaft 24)
1, a connecting rod 33 pivotally connected to the first rocking piece 31 by a pivot 32 having an axial center oriented in the left-right direction, and a longitudinally oriented connecting rod 33, and an axial center attached to the rear end of the connecting rod 33. Rocking piece 3 pivotally connected by a pivot 34 that turns the
5, a rotation shaft 36 fixed to the base of the second rocking piece 35 and rotatably provided on the support 16 so that the axis is directed in the left-right direction, and provided on the rotation shaft 36. A protruding piece 37 for raising and lowering the vertically movable wheel unit 19
(Made to contact the bracket 20 of the wheel unit 19).

The connecting rod 33 is fitted on the hollow base material 3. Needless to say, the base member 3 and the intermediate arm member 5 are formed with openings that allow the second rocking piece 35 to rock. Further, the second swinging piece 35 is configured by connecting two members in consideration of the convenience of assembly and the like.

In FIG. 3, the mechanical coupling device 29 in a state where the bottom plate 26 is in the horizontal state is illustrated by a solid line. In this state, the protruding piece 37 exerts a rotational force in the direction in which the bottom plate 26 falls down further from the wheel unit 19 (in FIG. 3,
Clockwise rotation). That is, the edge of the projecting piece 37 that exceeds the edge of the maximum radius centered on the rotation center of the rotating shaft 36 in the counterclockwise direction is made smaller than the maximum radius, and the edge that exceeds the counterclockwise direction is the bottom plate. When the 26 falls down, it comes into contact with the top wall of the bracket 20. Further, in a state where the bottom plate 26 is in the horizontal state, the wheel unit 19 is provided on the support 16 so that the wheel unit 19 does not further descend even if a force for further pushing the wheel unit 19 downward acts on the wheel unit 19. The stopper 38 comes into contact with the top wall of the bracket 20 from below. On the other hand, bottom plate 2
When 6 is in the upright state, the mechanical coupling device 29 moves so as to be in the above-described state.

[0018]

[Modifications and the like] Modifications and the like are described below. (1) The material and shape of the bottom plate 26 are arbitrary. (2) Instead of the structure in which the top wall of the bracket 20 of the wheel unit 19 is pushed by the protruding piece 37, the rotating shaft 36 and the bracket 20 may be connected by a link piece. In this case, since the bracket 20 swings up and down, the link piece and the bracket 20 are connected so that the swing of the link piece is transmitted to the bracket 20 but the swing of the link piece and the bracket 20 is not prevented. Needless to say. (3) The wheel unit 19 only needs to move up and down, that is, vertically move up and down.

[Brief description of the drawings]

FIG. 1 is a simplified side view showing an embodiment of the present invention.

FIG. 2 is a view taken along line II-II in FIG.

FIG. 3 is an enlarged view of a part of the part A in FIG.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a sectional view taken along line VV of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cart 2 Bottom frame 3 Base material 4 Arm material 5 Arm material 10 Revolving caster 14 Wheel 19 Wheel unit 21 Wheel 29 Mechanical connecting device 31 First rocking piece 32 Axis 33 Connecting rod 34 Axis 35 Second rocking piece 36 Rotating axis 37 projection

Claims (4)

[Claims] 1. A bottom frame which is long in the front-rear direction, is provided with turning casters at four corners of a lower surface, and is provided with wheel units which are not turned on left and right lower surfaces of a middle part in the front-rear direction, and which are vertically movable. In a bogie in which the bottom plate provided to be able to swing up and down directly or indirectly at the front or rear of the frame, and the grounding surface of the wheel of the wheel unit is made to be able to come and go with respect to the grounding surface of the wheel of the turning caster, The bottom plate and the wheel unit are interlocked by a mechanical interlocking device, and the mechanical interlocking device raises the wheel unit when the bottom plate stands up so that the contact surface of the wheel of the wheel unit is located above the contact surface of the wheel of the turning caster. When the bottom plate falls, the wheel unit is lowered and the contact surface of the wheel of the wheel unit is positioned below the contact surface of the wheel of the swivel caster. A trolley that is made to make it. 2. The mechanical interlocking device is pivotally connected to a first rocking piece provided on a rocking base of a bottom plate, and to the first rocking piece by a pivot having an axis oriented in the left-right direction. A connecting rod whose longitudinal direction is oriented in the front-rear direction, a second rocking piece pivotally connected to the other end of the connecting rod by a pivot whose axis is directed in the left-right direction, and a base of the second rocking piece are provided. It has a rotating shaft fixed to the bottom frame so that the axis is oriented in the left-right direction and rotatably provided on the bottom frame, and a protruding piece for lifting and lowering a vertically movable wheel unit provided on the rotating shaft. The bogie according to claim 1, wherein the wheel unit is biased upward by a biasing means such as a spring. 3. The wheel unit is provided directly or indirectly on the bottom frame so as to be able to swing up and down by a pivot whose axis is oriented in the left-right direction. 3. The bogie according to claim 2, wherein the bogie receives a rotational force in a direction in which the bottom plate falls down. 4. The base frame includes a hollow base member having a longitudinal direction directed back and forth, and front and rear portions and an intermediate portion of the base member.
A central portion directly or indirectly provided with three arm members having a longitudinal direction oriented in the left-right direction, and a swivel caster or a wheel unit is provided on the lower surface of the left or right end of the arm member; The truck according to claim 2, wherein the rod is fitted to the base material.