JP5254271B2 - Electric assist cart - Google Patents

Description

  The present invention relates to an electric assist cart, and more particularly, to an electric assist cart that facilitates the transfer of heavy objects by adding electric power wheels to a general cart.

  For example, an automobile assembly operation in a general automobile manufacturing factory is mainly performed by a flow operation using a robot. For this purpose, an assembly line including various assembly processes is formed. And, in each assembly process, parts to be assembled are delivered, but in order to transfer the parts to the delivery place prior to the delivery, a hand cart is often used. Some of them have a considerable weight, and the work of carrying them by hand on a cart is a heavy labor (in the present invention, it is assumed that parts weighing 100 kg or more are transported).

  In order to cope with the transport of such heavy objects, various so-called electric assist carts to which electric driving wheels are added have been proposed (Japanese Patent Laid-Open Nos. 10-109647, 2001-130414, and Japanese Patent Laid-Open No. 2001-130414). 2006-290319 publication, Unexamined-Japanese-Patent No. 2008-280021 etc.). Each of these electric assist carts includes a wheel having a general caster structure under the loading platform, and also includes an electric driving wheel below or below the loading platform, and drives the driving wheel. It is equipped with a motor and a battery that serves as a power source for the motor.

  However, in these conventional electric assist carts, since the loading platform is close to the ground surface, for example, a heavy load of 100 kg as assumed in the present invention is placed on the loading platform, and the parts are lifted from the loading platform to deliver the parts. It is necessary to bend the work of placing in the section. Therefore, when such work is repeated, there arises a problem that the operator easily hurts the waist and the like.

  In addition, the motors and batteries in these electric assist carts are often installed under the handle part that is removed from the loading platform and gripped when an operator pushes the cart. The trolley is vertically long. As a result, there is a problem that the difference between the inner and outer wheels of the front and rear wheels becomes large and the small turning is not good, and inconvenience is felt when changing the direction at right angles along the assembly line.

JP-A-10-109647 JP 2001-130414 A JP 2006-290319 A JP 2008-280021 A

  As described above, in the case of the conventional electric assist cart, the load on the operator is large because the position of the loading platform is low, the driving unit protrudes and becomes obstructive, and the bogie is vertically long so that a small turn is required. There was a problem that it was difficult to work.

  The present invention was made to solve the problem in the case of such a conventional electric assist cart, and by increasing the position of the loading platform, an operator can place a heavy object on the loading platform, or from there This reduces the burden of the operator from hurting his / her waist during the operation, reduces the risk of the driver from getting in the way, reduces the length of the carriage, and reduces the turn. It is another object of the present invention to provide an electric assist cart that can be operated and that can be unmanned.

The invention according to claim 1 for solving the above-described problems includes a bogie frame, an operation handle installed on a rear surface side of the bogie frame, a plurality of universal wheels provided on a lower surface of the bogie frame, and the bogie. A driving wheel arranged at the center of the lower surface of the frame so as to be in contact with the universal wheel at the same time, a driving means incorporated in the inside of the carriage frame and a driving control means for rotationally driving the driving wheel; bogie frame is constructed by assembling the pipe member into a box shape, and the front Symbol freely moving wheel underside is attached frame, an upper surface frame which constitutes the loading platform, intermediate frame disposed between the lower surface frame and the upper surface frame And the drive wheel is pivotally supported by a support frame installed in the intermediate frame .

  In one embodiment, the drive wheel is driven to rotate by the drive means to enable unmanned travel, and in that case, forward and backward operations are enabled. Further, a limit switch is installed on the bogie frame, and when the limit switch is turned on during the unmanned running of the bogie, it is possible to control the operation stop of the driving means. In that case, the drive control means may be able to control the drive means so that the carriage stops at a set position. The limit switch can be incorporated in a bumper installed on the bogie frame.

Further, in one embodiment, prior SL top frame on by placing the platform in the carrier and without the height of the loading platform is set in the range of 90 to 100cm from the ground.

  In one embodiment, the operation handle has a grip shape similar to a handle of a two-wheeled vehicle, and the operation handle has a rotary variable resistor for controlling a current supplied to the rotation driving means of the drive wheel. Incorporated. An emergency stop button for stopping the carriage by pressing may be provided on the carriage frame. Preferably, a multi-axis type is used as the universal ring. Furthermore, in one embodiment, the carriage is allowed to travel on a dedicated track, and means for determining whether or not the carriage frame is in a state capable of traveling on the track is installed.

  The present invention is as described above, and since the position of the loading platform is set high, the burden on the operator when placing heavy objects on the loading platform or picking up from the loading platform is reduced. The risk that an operator may hurt his / her waist during the work is reduced, and the length of the carriage can be suppressed by the drive unit being housed in the carriage frame. There is an effect that can be done.

  In addition, the electric assist cart can be pushed and released to run unattended. In this case, for example, the traveling direction is changed to a desired direction by causing the cart to self-run and hit against a curved wall. Operation such as running and stopping automatically is possible, and it is possible to carry out human-powered parts without delaying the flow and placing a heavy burden on the operator in the automobile manufacturing process etc. performed by flow work There is an effect.

It is a side view which shows the structure of one Embodiment of this invention. It is a perspective view which shows the use condition of one Embodiment of this invention. It is a figure which shows the effect | action of the limit switch installed in one Embodiment of this invention. It is a front view which shows other embodiment of this invention. It is a figure which shows the effect | action of other embodiment of this invention.

Preferred embodiments for carrying out the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, engagement Ru electrodeposition kinematic assisted trolley 1 to the present invention, the bogie frame 2 mainly includes an operating handle 11 which is installed on the rear side of the bogie frame 2 is disposed on the lower surface of the bogie frame 2 In general, four universal wheels 15, a drive wheel 16 disposed in the center of the lower surface of the carriage frame 2, a drive unit (motor 18) that is incorporated inside the carriage frame 2 and drives the drive wheel 16, It is comprised with the drive control part 10 which controls a drive part.

Bogie frame 2 is typically a metal pipe member is configured by assembling a box shape, a bottom surface frame 3 itself standing ring 15 is attached, a top frame 4 constituting the loading platform, the intermediate frame supporting the drive moving parts 5 is provided. The rear frame 6 of the carriage frame 2, that is, the frame on which the operator stands is formed higher than the front frame 7, and the operation handle 11 is fixedly installed on the upper portion thereof. The operation handle 11 preferably has a grip shape that is easy to grip, such as a handle of a two-wheeled vehicle, and is installed at a height that is easy for an operator to operate.

  Needless to say, the operation handle 11 is gripped when pushing or changing the direction of the carriage. Further, the operation handle 11 is operated by a turning operation similar to a grip operation in a motorcycle or a push button type switch. A signal for controlling the rotation of the drive wheel 16 can be transmitted to the drive control unit 10 by the switch operation after installation. For example, in the case of the former grip operation, a rotary variable resistor is incorporated in the operation handle 11, and the supply current to the motor 18 that rotationally drives the drive wheel 16 can be controlled according to the rotation of the operation handle 11. It is comprised so that it may become.

  At the four corners of the lower surface frame 3, swivelable freewheels 15 are attached. As this free wheel 15, it is recommended to use a multi-shaft type (having a plurality of shafts with different axis centers and usually two shafts) that is rich in direction change freedom and followability (FIG. 1). reference). A driving wheel 16 is disposed at the center of the lower surface frame 3. The drive wheel 16 is supported by a shaft support frame 17 extending from the intermediate frame 5, for example. A drive control unit 10 is disposed at the upper part of the shaft support frame 17, and a chain, a belt, or a gear for transmitting the rotational driving force from the motor 18 to the wheel shaft of the drive wheel 16 in the shaft support frame 17. Etc. are incorporated.

  For example, the motor 18 is installed and installed on the intermediate frame 5, and the battery 19 serving as a power source thereof does not protrude from the lower frame 3 (see FIG. 1) or the intermediate frame 5 (see FIG. 2). Installed. In the example shown in FIG. 2, the battery 19 and the drive control unit 10 are housed in one case.

  The upper frame 4 is provided with a platform 20 for constituting a loading platform. The table 20 may simply be placed on the upper surface frame 4. For example, the table 20 is placed so as not to slide sideways by means such as providing a frame portion inscribed or circumscribed on the upper surface frame 4 on the back surface thereof. Alternatively, it may be completely fixed. Further, the platform 20 is disposed so as to be at a height of about 90 to 100 cm from the ground, which is considered to be a height at which an operator can easily handle the heavy parts 30.

Engaging Ru electrodeposition kinematic assisted trolley 1 in the present invention, by releasing pushing the operating handle 11 in a state that operates the motor 18 can be unmanned. That is, it can be self-propelled and transported unattended. The unmanned is due the rotation of the drive wheel 16, therefore when the multi-axle universal wheel 15 to follow without any resistance, electrostatic movement assisted trolley 1 travels straight without wobbling it. In this case, the motor 18 can be controlled to rotate forward and backward by the grip operation, switch operation, or other operations, and automatic traveling in the forward direction or the backward direction can be performed by switching the forward and reverse directions. Is preferred.

In a preferred embodiment, the front frame 7, or both of the rear frame 6 and the front frame 7, bumpers 2 2 incorporating limit switches are installed (see Fig. 1). Typically, bumpers 2 2 is the same width as the bogie frame 2. The bumpers 2 2, for example, operated by striking the wall surface or the like during unmanned running of the electric assist cart 1, and sends an emergency stop signal to the drive control unit 10, the drive control unit 10 which has received the emergency stop signal Immediately shuts off the power to the motor 18 and stops the electric assist cart 1.

In another mode, the drive control unit 10 that has received this emergency stop signal immediately shuts off the power when a preset time or rotation speed has elapsed, without shutting off the power to the motor 18 immediately. The electric assist cart 1 is self-propelled. In this mode, for example, the curved surface 31 is formed on the wall surface, and the electric assist cart 1 is allowed to self-run toward the curved surface 31 and hit the curved surface 31 so as to be self-propelled thereafter. The operation is such that the electric assist cart 1 is changed in direction along the curved surface 31 and then stopped for a predetermined time, in other words, by self-propelling for a predetermined distance, so that the electric assist cart 1 is stopped almost at a desired stop position 32. (See FIG. 3).

In the unmanned traveling with such a change, for example, an operator who mounts a plurality of parts 30 on the electric assist cart 1 and operates on one side of the production line 33 is formed on the opposite side of the production line 33. This can be used when the electric assist cart 1 is pushed and released toward the curved surface 31 to be self-propelled and the parts 30 to be used are automatically supplied to the worker in the next process on the opposite side . Also during such operation of the electric dynamic assisted trolley 1, rich in turning freedom and conformability, freely moving wheel 15 of the multi-axle to function effectively.

  In a further preferred embodiment, one or a plurality of emergency stop buttons 24 are installed at any location on the carriage frame 2, preferably at a location that can be reached from any surrounding position. The emergency stop button 24 is used when an operator or a surrounding worker makes an emergency stop of the electric assist cart 1. A signal from the emergency stop button 24 is used to control the motor 18. Priority is given to signals.

  The electric assist cart 1 according to the present invention may be self-propelled along the track 26. For example, as shown in FIG. 4, the track 26 is formed with a groove 27 in which the drive wheel 16 travels, and the free wheel 15 is located outside the track 26. In this case, self-running condition detecting means 28 for detecting whether or not the drive wheel 16 is in a self-running state is provided on both sides of the drive wheel 16. The self-running condition detecting means 28 is composed of a limit switch 28a, a lever 28b, and a wheel 28c.

The lever 28b is rotatably attached to the limit switch 28a and rotates as the wheel 28c moves up and down. The self-propelled state is when the electric assist cart 1 is on the track 26. At this time, the wheel 28c is on the upper surface of the track 26, and the lever 28b is inclined (FIG. 5B ). reference). The limit switch 28 a determines that the lever 28 b is in a self- propellable state based on the tilted state of the lever 28 b , and transmits a corresponding signal to the drive control unit 10.

  In any of the above self-propelled modes, the signal for rotation control of the drive wheel 16 sent by the operator's operation has priority. For example, when a stop signal is transmitted from the operator, the self-propelled function is immediately stopped. To be done. In addition, the electric assist cart 1 according to the present invention is configured to be able to move forward and backward both when traveling by a pushing operation by an operator and when traveling independently.

  Although the present invention has been described in some detail with respect to its most preferred embodiments, it will be apparent that a wide variety of different embodiments can be constructed without departing from the spirit and scope of the invention, the invention being defined by the appended claims. It is not restricted to the specific embodiment other than limiting in. For example, the operation via the handle 11 or the emergency stop button 24 can be performed by remote operation, and sound can be generated during traveling or abnormal approach to a wall surface. Needless to say.

DESCRIPTION OF SYMBOLS 1 Electric assist cart 2 Bogie frame 3 Lower surface frame 4 Upper surface frame 5 Intermediate frame 6 Rear frame 7 Front frame 10 Drive control part 11 Operation handle 15 Free wheel 16 Drive wheel 17 Shaft frame 18 Motor 22 Bumper 24 Emergency stop button 28 Self-propelled Condition detection means

Claims (12)

A bogie frame, an operation handle installed on the rear surface side of the bogie frame, a plurality of free wheels arranged on the lower surface of the bogie frame, and a lower wheel center portion of the bogie frame arranged to be simultaneously grounded with the free wheel Drive wheels, and drive means and drive control means that are incorporated inside the carriage frame and rotationally drive the drive wheels,
The bogie frame is constructed by assembling a pipe material into a box shape, a bottom surface frame before Symbol freely moving wheel is attached, a top frame which constitutes the loading platform, the intermediate is disposed between the lower surface frame and the upper surface frame An electric assist cart comprising: a frame, wherein the drive wheel is pivotally supported by a support frame installed on the intermediate frame .   2. The electric assist cart according to claim 1, wherein the driving wheel is driven to rotate by the driving means to enable unmanned traveling.   The electric assist cart according to claim 2, wherein a limit switch is installed in the cart frame, and the operation stop of the driving means can be controlled when the limit switch is turned on during unmanned running of the cart.   The electric assist cart according to claim 3, wherein the limit switch is incorporated in a bumper installed on the cart frame.   The electric assist cart according to claim 3 or 4, wherein the drive control unit can control the drive unit so that the cart stops at a set position.   The electric assist cart according to any one of claims 1 to 5, wherein a platform is placed on the upper frame to form a loading platform, and the height of the loading platform is set in a range of 90 to 100 cm from the ground.   The electric assist cart according to claim 1, wherein the operation handle has a grip shape similar to a handle of a motorcycle.   The electric assist cart according to claim 7, wherein a rotary variable resistor for controlling a current supplied to the rotation driving means of the drive wheel is incorporated in the operation handle.   The electric assist cart according to any one of claims 1 to 8, wherein a multi-shaft type is used as the free wheel.   The electric assist cart according to any one of claims 1 to 9, wherein an emergency stop button is provided on the cart frame to stop the cart by pressing.   The electric assist cart according to claim 1, further comprising means for determining whether or not the vehicle is capable of self-propelling on a dedicated track and is capable of self-propelling on the track.   The electric assist cart according to claim 2, which enables forward and backward operations.

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