JP2018034708A - Transport vehicle for work - Google Patents

Abstract

An object of the present invention is to provide a working carrier capable of easily going over a step. A working vehicle (1) includes a loading platform frame (2), a loading platform (3), a connecting member (6), main wheels (4) and auxiliary wheels (5) connected to the lower part of the loading platform frame (2) by the connecting members (6), and the loading platform frame. 2 and a handle 8. The shortest distance D1 from the bed frame 2 to the bottom end of the stand 7 is shorter than the shortest distance D2 from the bed frame 2 to the bottom end of the main wheel 4, and the shortest distance D3 from the bed frame 2 to the bottom end of the sub wheel 5. is shorter than the shortest distance D2 from the loading platform frame 2 to the lowest end of the main wheels 4. [Selection drawing] Fig. 1

Description

  The present invention relates to a work vehicle.

  Conventionally, a unicycle-type work transport vehicle has been used when transporting transported materials such as production materials and waste in a site such as civil engineering or agriculture (for example, Patent Document 1). This type of work vehicle includes a loading platform frame, a loading platform, one wheel, a stand, and two handles disposed on the left and right sides of the loading platform frame with respect to the traveling direction. When the work carrier is pushed forward with both the left and right handles lifted by both hands, the wheels provided at the substantially lower front part of the cargo bed rotate, and the work carrier moves forward. Further, when the work vehicle is pulled rearward with each handle lifted, the wheels rotate and move rearward. In addition, a work transport vehicle provided with a plurality of wheels in the front-rear direction has also been proposed (for example, Patent Document 2).

JP 2001-328537 A Patent 4310555

  Such a work transport vehicle can be easily moved to a desired position by human power, and thus has been suitably used in a narrow passage or site where a truck or the like is difficult to enter. However, on topography with many steps and bumps, especially when the weight of the load is large, even if you try to overcome the step with the lever principle using the stand provided at the lower rear of the loading platform, the front of the loading platform may not lift as expected In many cases, the balance was lost and the cargo collapsed. For this reason, every time a step is encountered, the handle must be lowered, the front of the loading platform must be lifted, and the wheels must be placed on the step, which has problems in workability and running stability. In addition, there is room for improvement in terms of operability (steerability) and small turning even in a work transport vehicle provided with a plurality of wheels in the front-rear direction.

  Accordingly, an object of the present invention is to provide a working transport vehicle that can easily cross a step and has excellent operability.

  In order to achieve the above object, the present invention provides a cargo bed frame (3), a cargo bed (2) supported by the cargo bed frame, and a connecting member (6) connected to the lower side of the cargo bed frame. A main wheel (4) connected to the lower part of the cargo bed frame via the connecting member, and disposed at a substantially lower center of the cargo bed, and connected to the lower side of the cargo bed frame via the connecting member, A sub-wheel (5) arranged in front of the main wheel, the sub-wheel having a smaller diameter than the main wheel, and a stand (7) provided in a substantially vertical direction at a lower rear portion of the cargo bed frame And a handle (8) provided so as to protrude rearward from the rear end of the cargo bed frame.

  Further, the shortest distance (D1) from the cargo bed frame to the lowermost end of the stand is shorter than the shortest distance (D2) from the cargo bed frame to the lowest lower end of the main wheel, and the shortest distance of the auxiliary wheel from the cargo bed frame. The shortest distance (D3) to the lower end is preferably a working transport vehicle characterized by being shorter than the shortest distance (D2) from the cargo bed frame to the lowermost end of the main wheel.

  In addition, it is preferable that the shortest distance from the carrier frame to the lowest end of the stand is a working transport vehicle characterized by being longer than the shortest distance from the carrier frame to the center of the main wheel.

  Moreover, it is preferable that the width | variety of the said auxiliary | assistant wheel is a work transport vehicle characterized by being wider than the width | variety of the said main wheel.

  According to the present invention, it is possible to easily cross a step (obstacle). Therefore, every time a step is encountered, there is no need to collapse the load, and there is no need to lower the handle and lift the front of the loading platform to place the wheel on the step, which significantly improves running stability and workability. .

The side view at the time of driving | running | working of the work vehicle by embodiment of this invention. The operation | movement figure which shows the work vehicle of the state which is going to get over a level | step difference. FIG. 3 is a front view taken along the arrow III in FIG. 1. The bottom view of the work vehicle according to the embodiment of the present invention.

<1. Configuration>
A working vehicle according to an embodiment of the present invention will be described with reference to FIGS. For convenience of explanation, the arrows shown in FIGS. 1 and 2 define the front-rear direction (traveling direction) of the work transport vehicle. Moreover, the arrow shown in FIG. 3 has defined the left-right direction of the work vehicle. Furthermore, the arrows shown in FIG. 4 define the front-rear and left-right directions of the work transport vehicle. In the description based on the side view, regarding the pair of left and right components, only one of them will be described, and the description of the other will be omitted.

  As shown in FIG. 1, the work transport vehicle 1 includes a loading platform frame 2, a loading platform 3, a main wheel 4, a sub wheel 5, a connecting member 6, a stand 7, and a handle 8. .

  The loading platform 3 is a container capable of loading a load to be transported. Although the shape is not particularly limited, in this embodiment, a rectangular loading platform having an open upper side and a predetermined depth and having an outer shape and a bottom shape as shown in FIG. 4 is used.

  The loading platform frame 2 is a frame that supports the loading platform 3 as shown in FIGS. The carrier frame 2 is not particularly limited as long as it can connect other accessory parts (for example, a connecting member, a stand, and a handle) while firmly supporting the lower part of the carrier 3. The loading platform frame 2 of the present embodiment has a U-shape composed of a front member 21a and a pair of left and right side members 21b and 21c so that the lower portion of the loading platform 3 having a rectangular bottom surface can be supported on the front and both sides. And an at least one cross member 22 that bridges the side members 21b and 21c of the outer frame 21 and supports the lower surface of the loading platform 3.

  The side members 21b and 21c are preferably bent so as to follow the shape of the cargo bed 3, as shown in FIGS. Moreover, it is preferable that at least two cross members 22 are provided from the viewpoint of improving the strength of the cargo bed frame 2, and a total of three members (22a, 22b, 22c) in front, center, and rear are provided. More preferred. The material of the loading frame 2 is preferably made of metal from the viewpoint of strength and durability. Further, from the viewpoint of weight reduction, it is preferable that the outer frame 21 is a metal round pipe and the cross member 22 is a metal flat plate. A pair of left and right handles 8 are provided so as to project rearward from the rear end of the frame 2 (21b, 21c).

  The connecting member 6 is an intermediate member for attaching the main wheel 4 and the auxiliary wheel 5 to the loading platform frame 2 on the lower side of the loading platform frame 2. As shown in FIG. 1, the connecting member 6 includes a main wheel connecting portion 64 that is a portion connected to the main wheel 4 and a sub wheel connecting portion 65 that is a portion connected to the sub wheel 5. In addition to this, in order to increase the strength of the entire connecting member 6, a bridging portion 66 that bridges the main wheel connecting portion 64 and the auxiliary wheel connecting portion 65 is provided, or in the frame that the cargo bed frame 2 and the connecting member 6 create. A bracing portion 67 may be provided.

  Next, a method for connecting the connecting members 6 will be described. First, in the connecting member 6, the pair of left and right main wheels is connected to the main wheel connecting portion 64 so that the pair of left and right main wheel connecting portions 64 extends substantially vertically downward from the lower side of the loading frame 2. One end of the connecting portion 64 is fixed to the lower side of the central cross member 22b by welding or the like. By connecting vertically downward, an extra load on the connecting member 6 can be reduced, and the load of the loading platform can be transmitted to the main wheel directly below to obtain a high load resistance. The other ends of the pair of left and right main wheel connecting portions 64 are arranged on the left and right sides of the main wheel 4 so as to sandwich the main wheel 4 described later. The other end of the main wheel connecting portion 64 is engaged with the main wheel 4 via the axle 41. In this embodiment, since the joint 641 is provided at the other end of the main wheel connecting portion 64, the joint 641 is engaged with the main wheel 4 through the axle 41.

  The connecting method of the auxiliary wheel connecting portion 65 is almost the same as that of the main wheel connecting portion 64. One end of the pair of left and right main wheel connecting portions 65 is fixed to the lower side of the front cross member 22a. The other ends of the pair of left and right auxiliary wheel connecting portions 65 are arranged on the left and right sides of the auxiliary wheel 5 so as to sandwich the auxiliary wheel 5 described later. The other end of the auxiliary wheel connecting portion 65 is engaged with the auxiliary wheel 5 via the axle 51. In this embodiment, since the joint 651 is provided at the other end of the auxiliary wheel connecting portion 65, the joint 651 is engaged with the auxiliary wheel 5 via the axle 51.

  The main wheel 4 is a traveling wheel of the work transport vehicle 1. The size of the main wheel 4 is preferably larger to some extent from the viewpoint of working time. From the viewpoint of running stability on rough roads, it is preferable to use rubber wheels having high elasticity for the tire part. As described above, the position of the main wheel 4 is disposed substantially below the center of the loading platform 3, and is connected to the loading frame 2 via the main wheel coupling portion 64 of the coupling member 6.

  The auxiliary wheel 5 is a wheel used to get over a step (obstacle). The auxiliary wheel 5 is disposed in front of the main wheel 4. Moreover, the auxiliary | assistant wheel 5 is connected with the front cross member 22a via the auxiliary | assistant wheel connection part 65 as above-mentioned. In order to easily get over the step, the shortest distance D3 from the carrier frame 2 to the lowermost end of the auxiliary wheel needs to be shorter than the shortest distance D2 from the carrier frame 2 to the lowermost end of the main wheel 4. There is. Therefore, the outer diameter of the auxiliary wheel 5 is smaller than the outer diameter of the main wheel 4 in order to arrange the lowermost end of the auxiliary wheel 5 at a higher position from the ground. However, the diameter of the auxiliary wheel 5 must not be too small because the auxiliary wheel 5 is forced to travel on its own until the main wheel 4 rides on the step after the step. Therefore, it is preferable that the size of the auxiliary wheel is 1/3 to 1/2 of the diameter ratio with respect to the main wheel 4.

  The thickness of the auxiliary wheel 5 is thicker than that of the main wheel 4 so that it can withstand a high load when climbing a step with a small outer diameter. Further, in order to overcome the step, it is preferable to use the auxiliary wheel 5 in a state in which the air pressure of the auxiliary wheel 5 is increased to increase the elasticity. Furthermore, in order to further increase the mechanical strength, it is preferable to use a urethane wheel that can withstand a higher load and is more resistant to impact than a rubber wheel.

  The stand 7 is provided at the lower rear portion of the loading frame 2 in order to keep the loading platform 3 substantially horizontal when the work transport vehicle 1 is not used. The shape of the stand 7 is not particularly limited as long as it can withstand the load of the loading platform 3 and perform the above function. The shortest distance D1 from the loading platform frame 2 (21b, 21c) to the lowest end of the stand 7 needs to be shorter than the shortest distance D2 from the loading frame 2 to the lowest bottom of the main wheel 4. If the length of the stand 7 in the vertical direction is longer than this, when the work transport vehicle 1 faces a step, even if an attempt is made to lift the auxiliary wheel 5 by pushing down the handle 8 described later, This is because the lowermost end interferes with the ground. However, if the length of the stand 7 in the vertical direction is too short, the loading platform 3 may tilt backward when the work vehicle 1 is not used, which may cause collapse of the cargo. Therefore, the shortest distance from the cargo bed frame 2 (21b, 21c) to the lowest end of the stand 7 is preferably longer than the distance from the cargo bed frame 2 to the center 41 of the main wheel 4.

  As shown in FIGS. 1 and 2, in the work transport vehicle 1 of the present embodiment, the distance in the front-rear direction between the stand 7 and the main wheel 4 is greater than the distance in the front-rear direction between the main wheel 4 and the auxiliary wheel 5. Also long. Further, the center of gravity of the work transport vehicle 1 is located not between the main wheel 4 and the auxiliary wheel 5 but between the stand 7 and the main wheel 4 in the front-rear direction. More specifically, the center of gravity of the work transport vehicle 1 is slightly behind the center of the main wheel 4 in the front-rear direction, that is, in the vicinity of the central cross member 22b. For this reason, when the work carrier 1 is placed on a horizontal surface in a state where the cargo bed 3 is empty or a load is loaded on the cargo bed 3 without unevenness, the stand 7 and the main wheel 4 are grounded and the auxiliary wheel 5 is floated. It becomes a state. Thus, since the center of gravity is located near the center of the main wheel 4 and slightly behind the center of the main wheel 4 and the auxiliary wheel 5 is small in diameter and light in weight, the direction can be easily changed around the main wheel 4 as an axis. That is, it is excellent in operability (steerability).

  Next, operation | movement of the working transport vehicle 1 by embodiment of this invention is demonstrated based on FIG. FIG. 1 shows a state of traveling with the handle 8 of the work transport vehicle 1 being lifted. The distance in the vertical direction from the ground to the lowermost end of the auxiliary wheel 5 during traveling is defined as X, and the vertical distance from the ground to the lowermost end of the stand 7 is defined as Y.

  FIG. 2 shows a state where the work transport vehicle 1 gets over the step. When climbing over the step in FIG. 2, the handle 8 is pushed down until the stand 7 reaches the ground, so the lowermost end of the auxiliary wheel 5 is at a position approximately X + Y higher than the ground before climbing over the step. After the auxiliary wheel 5 has climbed up the step, when the wheel 8 is pushed forward while gradually returning the height of the handle 8 upward, the main wheel 4 continues to try to get over the step. After the main wheel 4 gets over the step, the running is the same as running on a flat road.

<2. Effect>
In the present embodiment, since the auxiliary wheel 5 having an outer diameter smaller than that of the main wheel 4 is disposed in front of the main wheel 4, it is possible to easily cross the step (obstacle). Therefore, according to the work transport vehicle 1 of the present embodiment, the load does not collapse every time a step is encountered, and it is also necessary to lower the handle and lift the front of the loading platform to place the wheel on the step. Therefore, running stability and workability are remarkably improved. This feature is particularly effective in situations where the road environment is poor, such as a site where earth and sand and rubble are scattered due to a sediment disaster. For example, although it is difficult to get over railroad rails with a normal unicycle, it is possible with the work vehicle 1 of this embodiment.

  Moreover, in this embodiment, since the shortest distance D1 from the carrier frame 2 (21b, 21c) to the lowest end of the stand 7 is shorter than the shortest distance D2 from the carrier frame 2 to the lowest lower end of the main wheel 4, If the position of the handle 8 is pushed down when the transport vehicle 1 rides on the step, the auxiliary wheel 5 can be pushed up to a higher position without causing the lowest end of the stand 7 to interfere with the ground.

  When the width of the auxiliary wheel 5 is narrower than the width of the main wheel 4, when the auxiliary wheel 5 rides on the step, the wheel easily slides to the left and right depending on the unevenness of the step, and the traveling of the work transport vehicle 1 is left and right. It tends to be unstable. However, in this embodiment, since the width of the auxiliary wheel 5 is thicker than the width of the main wheel 4, the auxiliary wheel can firmly catch the stepped road surface. On soft ground, the uneven ground is crushed and transported for work. The traveling of the car 1 can be stabilized.

<3. Modification>
The working transport vehicle 1 according to the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope described in the claims.

  For example, although the work vehicle 1 according to the above-described embodiment has the auxiliary wheel 5 wider than the main wheel 4, the auxiliary wheel 5 may be the same width as the main wheel 4 or may be larger than the main wheel 4. The width may be narrow. In this case, the auxiliary wheel can be reduced in weight, and the handling can be further improved.

  Further, there may be a plurality of auxiliary wheels 5. When there are a plurality of auxiliary wheels 5, they may be arranged vertically or in parallel in the horizontal direction. When the two wheels are arranged in parallel, the same effect as in the case of one thick wheel can be obtained. Further, although one main wheel 4 is preferable, a plurality of main wheels 4 may be arranged in parallel.

  As described above, the configuration according to the present invention is suitable for use in a work vehicle that can easily get over a step.

1 Working vehicle, 2 cargo frame, 3 cargo bed, 4 main wheels, 5 secondary wheels, 6 connecting members, 7 stands, 8 handles

Claims (5)

Loading platform frame (3),
A loading platform (2) supported by the loading platform frame;
A connecting member (6) connected to the lower side of the cargo bed frame;
A main wheel (4) connected to the lower side of the cargo bed frame via the connecting member and disposed at a substantially central lower portion of the cargo bed;
A sub-wheel (5) connected to the lower side of the cargo bed frame via the connecting member and disposed in front of the main wheel, the sub-wheel having a smaller diameter than the main wheel;
A stand (7) provided in a substantially vertical direction at the rear lower part of the cargo bed frame;
A work vehicle (1) comprising a handle (8) provided so as to project rearward from a rear end of the cargo bed frame. The shortest distance (D1) from the cargo bed frame to the lowest end of the stand is shorter than the shortest distance (D2) from the cargo bed frame to the lowest bottom of the main wheel,
The shortest distance (D3) from the cargo bed frame to the lowermost end of the auxiliary wheel is shorter than the shortest distance (D2) from the cargo bed frame to the lowermost end of the main wheel. Work carrier.   The working transport vehicle according to claim 2, wherein a shortest distance from the cargo bed frame to a lowermost end of the stand is longer than a shortest distance from the cargo bed frame to the center of the main wheel.   The work vehicle according to any one of claims 1 to 3, wherein a width of the auxiliary wheel is larger than a width of the main wheel. The distance between the stand and the main wheel in the front-rear direction is longer than the distance between the main wheel and the sub-wheel in the front-rear direction, and the front-rear direction is not between the main wheel and the sub-wheel but the stand. The center of gravity is located between the main wheels,
When the work carrier is placed on a horizontal surface in a state where the loading platform is empty or a load is loaded on the loading platform without unevenness, the stand and the main wheel are grounded, and the auxiliary wheel is in a floating state. The working transport vehicle according to claim 1, wherein:

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