JPH0230232Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a self-propelled step stool that is extremely convenient to be installed on an automobile assembly line.

As is well known in the art, in automobile manufacturing factories, frames and bodies are mounted on an assembly line and moved continuously at a relatively low speed, while assembling a large number of parts one after another. It is done.
For this purpose, at each work station where a predetermined range of parts is assembled,
Workers move along the line while installing and adjusting parts, and after completing the work, return to the initial position of the station and repeat the same work, so they have to walk a reasonable distance in addition to the original assembly work. There was a problem in which the fatigue was significant.

This invention was devised in view of the above circumstances.
A rail arranged along the conveyor of the assembly line, a work step mounted on the rail so as to be freely movable via rolling wheels, and a working step mounted on the step and in the direction of movement of the step. The gist of the present invention is a self-propelled step stool characterized by comprising a variable speed and reversible drive device configured to change the moving speed.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. First, in Figures 1 to 3, 1
0 is an assembly line conveyor, on which, for example, a truck frame is mounted.
move slowly and continuously in the direction. Reference numeral 12 denotes a pair of parallel rails arranged along the conveyor 10, and in this embodiment, the ridgeline of the chevron-shaped material is on top and both ends are in contact with the factory floor F so that the cross-sectional shape is triangular. It is laid down. Reference numerals 14 each have a drum shape and are mounted on the rails 12 via front wheels 16 and rear wheels 18 so as to be freely movable on the rails; 20 are mounted on the above-mentioned rails 14; Equipped with a reversible and variable speed air motor, 22
26 is a driving sprocket vehicle connected to the air motor via a speed reducer 24, and 26 is the shaft 3 of the front wheel.
A driven sprocket wheel 32 fixed on the air motor 20 and connected to the driving sprocket wheel 22 via the drive chain 28 is supported on the step platform 14 and is a control box for controlling the operation of the air motor 20. More details later in the 4th section.
This will be explained with reference to the figures. 34 is an engagement piece provided on the side of the rail 12 at a predetermined position to limit the end of the forward stroke of the step 14, and 36 is provided on the side of the rail 12 at a predetermined position to limit the end of the backward stroke of the step 14. The engagement piece 38 is a limit switch that cooperates with the forward and backward engagement pieces 34 and 36.

Next, in FIG. 4, 40 is a master valve connected to a compressed air source 42, and is controlled by the limit switch 38 and a reset button 44 manually operated by the operator. 46 is a first select valve connected to the ON side of the master valve 40 and controlled by the operator, and either forward F or return R is selected. 48
is a second select valve connected to the forward F side of the first select valve and controlled by the operator, and either speed N, which synchronizes with the conveyor 10, or high speed H, which moves faster, is selected. 50,5
Reference numerals 2 and 54 are both throttle valves that adjust the amount of air supplied to the air motor 20, and respectively set the return speed, synchronization speed with the conveyor 10, and high-speed running speed to desired values.

In the above device, when the step stool 14 is at the predetermined initial position, the master valve 40 is in the OFF state due to the cooperation of the limit switch 38 and the engagement piece 36, and the air motor 20 is stopped. To start work from this current position, the author on the step stool 14 presses the reset button 44 on the control box 32, which switches the master valve 40 to the ON state and starts compressed air from the compressed air source 42. 1 select valve 46. Then, when the same valve 46 is operated to select forward F, compressed air is further supplied to the second select valve 48. The second select valve 48 normally has a synchronous speed N
Since compressed air is supplied to the air motor 20 through the throttle valve 52, the motor rotates in the forward direction at a set speed, and the reducer 24, the driving sprocket wheel 22, the drive chain 28, and the driven sprocket wheel 26 After that, the front wheel 16 rotates, and the step stool 14 runs by itself at a speed synchronized with the line conveyor 10. Therefore, the operator does not need to assemble parts or perform adjustment work while walking following the conveyor 10. When the step stool 14 reaches the front end of the work station in this way, the limit switch 38 comes into contact with the engagement piece 34, so the master valve 40 is switched to the OFF state and the supply of compressed air to the air motor 20 is cut off. Therefore, the step stool 14 stops at the fixed position. Therefore, the worker is the first
When selecting the select valve 46 to the return position R,
Compressed air is supplied to the air motor 20 through the throttle valve 50 and the motor rotates in reverse, causing the front wheels 16 to reverse and the step stool 14 to return to its initial position. When the limit switch 38 comes into contact with the engaging piece 36, the master valve 40 is turned off and the air motor is also stopped, so that the step returns to the initial stroke starting position. In addition, if it is desired to move the step stool 14 forward rapidly for various reasons, the first select valve 46 may be selected to move forward (F), and the second select valve 48 may be selected to high speed H at the same time. In this case, compressed air is regulated by the throttle valve 54, and the air motor rotates at high speed in the forward direction, and travels at high speed to the desired position (until the second select valve 48 is selected to synchronous N again).

As mentioned above, the self-propelled step stool according to the present invention is equipped with a rail arranged along a conveyor of an assembly line and mounted on the rail so as to be freely movable via rolling wheels. The invention is characterized by comprising: a working step; and a variable speed and reversible drive device mounted on the step and configured to change the moving direction and speed of the step; Significantly reduces the required walking distance for people,
This is extremely beneficial as it prevents worker fatigue.

[Brief explanation of the drawing]

Figure 1 is a side view showing one embodiment of the present invention;
3 is a plan view of the apparatus shown in FIG. 1, FIG. 3 is a front view of the apparatus shown in FIGS. 1 and 2, and FIG. 4 is a functional explanatory diagram of the control box 30 in the above apparatus. 10... Assembly line conveyor, 12... Rail, 14... Step stool, 16... Front wheel, 18... Rear wheel, 20... Air motor, 32... Control box.

Claims (1)

[Scope of utility model registration request] A rail arranged along the conveyor of the assembly line, a work step mounted on the rail so as to be freely movable via rolling wheels, and a working step mounted on the step and in the direction of movement of the step. and a variable speed and reversible drive device configured to change the moving speed.