JP5293033B2 - Transport cart - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple-structure carriage easy to adjust the spring force supporting a deck, and proper to transport light loads. <P>SOLUTION: In an automated carriage 1, the deck 2 provided in a movable carriage part 10 freely to be elevated is supported by a body 60 provided above the deck, a wire 62 to be drawn from the body, and a spring balancer 6 with an energizing means, which energizes the wire 61 in the winding direction, freely to be elevated. When the wire 61 is pulled out by the weight of a transported material M placed on the deck 2 and the deck is lowered, driving wheels 5 are driven to move forward through a rack part 3 and a pinion part 31 as operation changing means for changing the upward/downward movement of the deck 2 to the turing operation, and the wire 61 is rewound by taking out the transported material M and the deck 2 is pulled up, and the driving wheels 5 are driven to move backward with the upward movement of the deck 2. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a transport carriage.

  Conventionally, in an assembly line of an automobile factory or the like, vehicle assembly members are transported by an unmanned transport cart. As this type of transport cart, there is an automatic transport cart (AGV) driven by an electric motor. In an electric automatic conveyance cart, an electric motor, a battery, and a control device are mounted on the cart itself, and maintenance work such as charging of the battery and maintenance of the motor and the control device is troublesome.

Therefore, as an automatic conveyance cart that does not use an electric motor, the cart is moved forward using the weight of the conveyed item, and energy is stored with the forward movement of the cart, and the stored energy is extracted after the conveyed item is taken out from the cart. There is one in which the carriage is moved backward (see Patent Document 1).
FIG. 4 shows a typical transport cart of this kind. 1 A of conveyance trolleys are provided with the loading platform 2 which can be raised / lowered to the trolley | bogie part 10 which consists of a frame material of a metal bar. The loading platform 2 can be moved up and down by inserting a plurality (four) of guide shafts 20 extending downward into guide members 11 provided in the cart unit 10 so as to be slidable in the vertical direction. Along the outer periphery of the shaft 20, it is supported by a coil spring 9 provided between the loading platform 2 and the guide member 11. Further, the loading platform 2 is provided with a rack portion 3 that extends downward to the lower side of the guide shaft 20 and moves up and down together with the loading platform 2, and a pinion portion 31 that meshes with the rack portion 3 and converts the raising / lowering operation of the rack portion 3 into a rotation operation. The pinion unit 31 transmits the rotation of the pinion unit 31 to the drive wheels 5 by a plurality of gears 39.

When the transport vehicle 1A places the transported object M on the loading platform 2, the loading platform 2 descends against the urging force of the coil spring 9 due to its weight, and this lowering is converted into a rotational operation by the rack section 3 and the pinion section 31. Then, it is transmitted to the drive wheel 5 to move forward.
After the conveyance, when the conveyed product M is taken out from the loading platform 2, the loading platform 2 is pushed up by the coil spring 9, and as the loading platform 2 rises, the pinion portion 31 rotates in the opposite direction to the above-described descending state, This reverse rotation is transmitted to the drive wheel 5 to move backward.
Japanese Patent Application Laid-Open No. 2004-331052

The transport cart 1A is configured to support a load carrier 2 with four guide shafts 20 and four coil springs 9 and transport a heavy object (about 20 kg) such as an automobile transmission. By the way, in the structure of 1 A of conveyance trolleys, although the coil spring 9 of the spring force according to the weight of a conveyed product will be used, adjustment of the spring force of the coil spring 9 cannot be performed when conveying the conveyed product from which weight differs. The coil spring 9 must be replaced. Further, even when the horizontal balance of the loading platform 2 is disrupted due to deterioration of some coil springs 9 and the like, the coil springs 9 cannot be finely adjusted and must be replaced. For exchanging 9, it is necessary to pull up the loading platform 2 and pull out the guide shaft 20 from the guide member 11, which takes time.
Further, since the transport carriage 1A is complicated in structure, the weight of the transport carriage itself is heavy, so it cannot be said that the mobility is good and it is not suitable for transporting a lightweight object.
Accordingly, it is an object of the present invention to provide a transport carriage that can easily adjust the spring force without removing the spring member, can finely adjust the spring force, and is particularly suitable for transporting a light member. It was made.

The invention according to claim 1 is a movable carriage part, a cargo bed installed on the carriage part so as to be movable up and down, a cargo bed support means for supporting the cargo bed so as to be movable up and down, and converting the lifting and lowering operation of the cargo bed into a rotation operation An action converting means for driving, and a drive wheel that is rotationally driven through the action converting means to move the carriage unit,
The drive wheel is driven forward by the lowering operation of the cargo bed that is lowered by the weight of the transported object placed on the cargo bed,
In the transport cart that lifts the load platform after the transported object is taken out from the load platform and causes the drive wheels to be driven backward by the lifting operation of the load platform,
The cargo bed is provided with a pair of left and right guide means comprising a guide piece that is provided at the center of the side edges on both the left and right sides and extends vertically downward, and a guide rail that is provided on the carriage and slides and guides the guide piece. Is guided up and down by
As the loading platform support means, a pair of left and right main body portions installed at the upper end of the cart portion at the upper position of the left and right guide rails, and a drawer end that can be pulled out from the main body portion at the center of the left and right side edges of the loading platform. Using a spring balancer comprising a connected wire and a spring that can adjust the biasing force as a biasing means that biases the wire in the winding direction,
The operation converting means includes a rack portion that extends vertically downward from the loading platform and moves up and down integrally with the loading platform at the same height as the guide piece, and a pinion portion that meshes with the rack portion, and the rack The rotation operation of the pinion part rotating by raising and lowering the part is transmitted to the drive wheel,
The wire is pulled out by the weight of the conveyed product, the loading platform is lowered, and the wire is rewound by the removal of the conveyed product to lift the loading platform.

Since a spring balancer is used as a carrier support means, the structure is simpler than that of a conventional carriage using a coil spring. The spring balancer is easy to install on the carriage, and the spring balancer is a spring that provides the lifting force for the carrier. The adjustment of the force is easy, and it can be widely applied to the conveyance of a plurality of kinds of lightweight objects having different weights. The spring spring can easily adjust the winding urging force of the wire by changing the number of windings.

  An embodiment of the present invention will be described with reference to FIGS. In the present embodiment, the present invention is applied to a transport carriage that transports parts, for example, an air conditioning unit (weight approximately 5 kg), which are assembled in an automobile compartment, between an assembly line of an automobile factory and a parts storage shelf. is there. In addition, the conveyance cart moves back and forth linearly over a short distance (about 5 m) between the component storage shelf and the assembly line.

  As shown in FIG. 1 and FIG. 2, the transport carriage 1 includes a carriage unit 10 that can be moved by a pair of left and right drive wheels 5 and a pair of left and right auxiliary wheels 51, a carriage 2 that can be moved up and down, The operation conversion means 3 which changes the raising / lowering operation | movement to rotational operation is provided. The carriage unit 10 has a frame structure made of metal square pipes, and a plurality of horizontal frames 102, 103, 104, and 105 that connect four vertical frames 101 and their upper ends, lower ends, and intermediate positions in a rectangular shape in the horizontal direction. And form a vertically long, rectangular parallelepiped shape. Each frame is made of aluminum pipe material to reduce weight.

  An axle 50 is provided at the lower end of the carriage unit 10 so as to bridge between a pair of left and right bearings 106 provided on the left and right lateral frames 103, and the left and right drive wheels 5 are supported by the axle 50. The left and right drive wheels 5 are fixed to the axle 50 and rotate integrally with the axle 50. Left and right auxiliary wheels 51 are installed on the front side of the drive wheels 5 at the lower end of the carriage unit 10.

A pair of left and right guide rails 4 serving as guide means for guiding the lifting and lowering of the loading platform 2 are installed on both the left and right sides of the carriage unit 10. Each guide rail 4 is made of an aluminum rail material having a substantially square C-shaped cross section, although not shown in the drawing, with its opening directed toward the center of the carriage unit 10 and the upper end of the rail at the left and right sides of the upper and lower centers of the carriage unit 10. The horizontal frame 104 is coupled to the central portion in the front-rear direction, and the lower end of the rail is coupled to the central portion in the front-rear direction of the left and right horizontal frames 103 at the lower end of the carriage unit 10 so as to bridge the horizontal frames 104 and 103 up and down. It is.

The loading platform 2 has a horizontal plate shape, and a roller conveyor section 21 that facilitates the forward and backward movement of the conveyed product M is installed on the upper surface thereof.
Corresponding to the left and right guide rails 4 of the carriage unit 10, the loading platform 2 is provided with a pair of left and right guide pieces 41 at the front and rear centers of the left and right side edges, respectively. Each guide piece 41 is a synthetic resin rod having a substantially T-shaped cross section, and its upper end is connected to the central outer surface of the side edge of the loading platform 2 and extends vertically downward. The guide piece 41 has a wide section with a T-shaped cross section inserted into the guide rail 4 and a narrow section inserted into the opening of the guide rail 4 so as to be slidably fitted along the guide rail 4. Thus, the loading platform 2 is guided up and down by the guide rails 4 and the guide pieces 41 that slide along the guide rails 4.

  The loading platform 2 is hung from above by a pair of left and right spring balancers 6 serving as loading platform support means at the positions above the left and right guide rails 4 at the front and rear center portions of the left and right side edges. The spring balancer 6 is a well-known product, and a reel is provided inside a circular container-like case member 60 that is a main body, and includes a wire 61 that can be wound around the reel and pulled out from the case member 60. The spring balancer 6 incorporates a spring for biasing the drawn wire 61 in the winding direction. The spiral spring spring has one end connected to the case side and the other end connected to the reel side. The wire 61 is wound in the winding direction by winding the reel side and increasing or decreasing the number of windings of the spring spring. The spring force can be adjusted, and this adjustment can be easily performed with a single tool such as a screwdriver.

  The left and right spring balancers 6 are respectively provided so as to be suspended in the front-rear center on the left and right lateral frames 102 at the upper end of the carriage unit 10 via the mounting bracket 62 at the upper end of the case member 60. Both spring balancers 6 connect the tips of the drawn wires 61 to the front and rear centers of the left and right side edges of the loading platform 2, respectively, and support the loading platform 2 to be lifted upward by the urging force of winding the wire 61. .

  Note that the upper limit position of the loading platform 2 when it is lifted is restricted by a stopper (not shown), and the upper surface of the loading platform 2 is in an empty state, and the upper surface of the loading platform 2 moves to the transportation cart 1 side from the storage shelf S. It is set at a height position that is almost horizontal to the platform.

  As the operation conversion means, a rack portion 3 that protrudes vertically downward from the center of the lower surface of the loading platform 2 and moves up and down integrally with the loading platform 2, is provided on the cart portion 10 side, meshes with the rack portion 3, and It is comprised with the pinion part 31 rotated by raising / lowering.

The rack portion 3 is joined by overlapping a flat mounting bracket formed integrally with the upper end of the rack portion 3 on the center of the lower surface of the loading platform 2.
The pinion unit 31 is supported by the left and right bearings 107 provided on the left and right horizontal frames 105 in the middle of the carriage unit 10 and the rotating shaft 30 spanned between them, and rotates together with the rotating shaft 30. is there. Further, a sprocket 32 is provided on the rotating shaft 30 beside the pinion portion 31 so as to rotate integrally with the pinion portion 31.

The sprocket 32 of the pinion portion 31 and the sprocket 52 provided on the axle 50 of the drive wheel 5 are connected by a chain member 34 so that the rotation of the pinion portion 31 is transmitted to the drive wheel 5.
In addition, 35 of FIG. 1 is a pressing part that presses the rack part 3 toward the pinion part 31 so that the rack part 3 and the pinion part 31 are not disengaged, and 350 is a column that supports the pressing part 35.

  As shown in FIG. 1, when the air conditioning unit M is placed on the loading platform 2 from the storage shelf S, the transport cart 1 pulls out the wire 61 against the urging force of the spring balancer 6 due to its weight and lowers the loading platform 2. As the rack part 3 descends (in the direction of arrow D), the pinion part 31 rotates in the direction of arrow F, the drive wheel 5 rotates in the direction of arrow F, and the transport carriage 1 moves forward (in the direction of white arrow F). ).

As shown in FIG. 3, when the transport carriage 1 arrives on the assembly line L side, the carriage 2 is lowered by a stopper (not shown) provided in the carriage section 10 to stop the advancement of the transport carriage 1. The stopper for restricting the upper limit of the lifting of the loading platform 2 and the stopper for regulating the lowering or lowering of the loading platform 2 are preferably provided in, for example, the guide rail 4 so as to regulate the raising and lowering of the guide piece 41. .
When the air conditioning unit M is moved from the loading platform 2 to the platform on the assembly line L side and left empty, the wire 61 is rewound by the restoring force of the spring spring of the spring balancer 6, and the loading platform 2 and the rack section 3 are raised (in the direction of arrow U). ), The pinion portion 31 and the drive wheel 5 rotate in the direction of the arrow R through the pinion portion 31, and the transport carriage 1 moves backward in the direction of the white arrow R to return to the storage shelf side.

  In order to reciprocate the conveyance carriage 1 between the storage shelf S and the assembly line L, it is desirable to guide the conveyance carriage 1 with a track rail. For example, the track rail may be a rail that rolls and guides the drive wheels 5 and the auxiliary wheels 51, or a narrow linear groove having a U-shaped cross section is provided on the floor surface between the storage shelf S and the assembly line L. On the other hand, a pin that protrudes downward and is inserted into the groove may be provided at the lower end of the transport carriage 1, and the pin may be guided by the groove.

According to the present invention, since the pair of left and right spring balancers 6 are used as the load carrier support means for supporting the load carrier 2 and pulling it upward, the structure can be simplified compared to the conventional structure, and the conveyance carriage 1 itself can be reduced accordingly. Since the weight can be reduced, the mobility is improved and it is suitable for transporting lightweight objects.
In addition, the spring balancer 6 can easily adjust the spring force for lifting the loading platform 2 with a single tool such as a screwdriver, and can be fine-tuned. Therefore, it is suitable for transporting various types of transported objects having different weights.
In the loading platform 2 of the transport carriage 1, since the front and rear center portions of the left and right side edges guided by the guide rail 4 are supported from above by a pair of left and right spring balancers 6, the horizontal balance is not easily lost. Even if the horizontal balance is lost, the balance can be easily maintained by fine adjustment of the spring force of the left and right spring balancers 6.

FIG. 4 is a side view showing a transport cart of the present invention, with a part of the frame of the cart section cut away, and an explanatory view of the forward drive of the cart by lowering of the loading platform. It is a front view of the said conveyance trolley. FIG. 4 is an explanatory view of the backward driving of the cart by the lift of the loading platform corresponding to FIG. It is a schematic side view of the conventional typical unmanned conveyance cart.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carriage truck 10 Carriage part 2 Cargo bed 3 Rack part (operation | movement conversion means)
31 pinion part (operation conversion means)
4 Guide rail (guide means)
41 Guide piece (guide means)
5 Drive wheels 6 Spring balancer (loading platform support means)
60 Case member (main body)
61 Wire M Carriage

Claims (1)

A movable carriage unit, a loading platform installed on the carriage unit so as to be movable up and down, a loading platform support means for supporting the loading platform so as to be movable up and down, an operation converting means for converting a lifting operation of the loading platform into a rotational operation, Driving wheels that are rotationally driven through the operation conversion means and move the carriage unit,
The drive wheel is driven forward by the lowering operation of the cargo bed that is lowered by the weight of the transported object placed on the cargo bed,
In the transport cart that lifts the load platform after the transported object is taken out from the load platform and causes the drive wheels to be driven backward by the lifting operation of the load platform,
The cargo bed is provided with a pair of left and right guide means comprising a guide piece that is provided at the center of the side edges on both the left and right sides and extends vertically downward, and a guide rail that is provided on the carriage and slides and guides the guide piece. Is guided up and down by
As the loading platform support means, a pair of left and right main body portions installed at the upper end of the cart portion at the upper position of the left and right guide rails, and a drawer end that can be pulled out from the main body portion at the center of the left and right side edges of the loading platform. Using a spring balancer comprising a connected wire and a spring that can adjust the biasing force as a biasing means that biases the wire in the winding direction,
The operation converting means includes a rack portion that extends vertically downward from the loading platform and moves up and down integrally with the loading platform at the same height as the guide piece, and a pinion portion that meshes with the rack portion, and the rack The rotation operation of the pinion part rotating by raising and lowering the part is transmitted to the drive wheel,
A transport carriage characterized in that the wire is pulled out by the weight of the transported object and the loading platform is lowered, and the wire is rewound by the removal of the transported object and the loading platform is pulled up.

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