JPH04166466A - Continuous transport device and method thereof - Google Patents

Abstract

PURPOSE:To deal of automatic processes having different cycle time by placing a transport line to transport works with an optional on one part against a transport line to transport works with a fixed pitch, making both lines approach so as to be in parallel, and transporting works. CONSTITUTION:A continuous transport device is constituted of a fixed pitch transport line L1 and an optional pitch transport line L2, the optional pitch line L2 is formed into an annular line, and both are lapped in parallel between confluent point X and the diverting point Y of both lines L1, L2. A plurality of self-moving vehicles 33 provided on the optional pitch transport line L2 are respectively provided with control boxes, and their transport speed and stop positions are optionally instituted. When a hanger is transport along the decided pitch transport line L1 to the confluent point X with the optional pitch transport line L2, the hanger is detached from the line L1 and transport with the self-moving vehicle at optional pitch. When the hanger is transported up to the diverging point Y, the hanger is returned to the fixed pitch transport line L1 again.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus and method for continuously transporting a workpiece such as a vehicle body to a plurality of work positions.

(Prior art) In order to automate efficiently on an automobile manufacturing line, a plurality of work positions are arranged on the line, and a conveyance device transports the car body along the line, and a predetermined position is placed at each work position. The work is being done on the car body.

Specific examples include JP-A No. 60-82476 and Utility Model Application No. 6
There is one disclosed in No. 2-77069.

The conveying device disclosed in Japanese Patent Application Laid-Open No. 60-82476 has a shuttle conveyor disposed between an inlet side suspended conveyor device driven by a chain and an output side suspended conveyor device also driven by a chain, Predetermined work is carried out while transporting the vehicle body intermittently at a fixed pitch.

On the other hand, in Utility Model Application No. 62-77069, the workpiece is transported by a self-propelled vehicle, and the speed of the self-propelled vehicle is set low at the working position, and the workpiece is transported at high speed at other locations. There is.

(Problems to be Solved by the Invention) The conveying device disclosed in Japanese Patent Application Laid-Open No. 60-82476 can only convey a vehicle body at a certain width. Therefore, for example, in the engine assembly process, when trying to assemble different models of engines to different vehicle bodies using one mounting trolley, it is possible to simply change the stopping position of the transported vehicle body slightly. Even if the position of the elements, ie, the position of the mounting cart or the set position of the engine, can be left as they are, fixed-pitch transport using a shuttle cannot accommodate this.

On the other hand, if a self-propelled vehicle is used as in Utility Model Application No. 62-77069, it is easy to change the transport pitch of the vehicle body, but in the automobile manufacturing line, work robots are installed at regular intervals, and the positions of these robots are In many cases, it is more advantageous to transport vehicle bodies accurately and intermittently, and it is disadvantageous from a cost perspective to use a transport line entirely using self-propelled vehicles.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a transport line that transports workpieces at a fixed pitch, and a transport line that transports workpieces at an arbitrary pitch so that each line is parallel to the transport line that transports the workpiece at a certain pitch. The two lines were placed close together so that workpieces could be transferred between the two lines.

(Function) The hanger that supports the workpiece is transported along the constant pitch transport line that runs by the driving force of the chain to the junction with the arbitrary pitch transport line by the self-propelled vehicle, and at this junction the hanger is transferred to the self-propelled vehicle transport line. The hanger is then transferred by a self-propelled vehicle to a branching point of both lines while accompanying the running of the chain, and at this branching point, the self-propelled vehicle and the hanger are disconnected and the chain and hanger are connected. Transfer the hanger to the constant pitch conveyance line again.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic plan view of a continuous conveyance device according to the present invention, and the continuous conveyance device is composed of a constant pitch conveyance line L1 and an arbitrary pitch conveyance line L2, and the arbitrary pitch conveyance line L
2 is a ring-shaped part thereof, that is, a constant pitch conveyance line L1
The confluence point X and the branch point Y of the arbitrary pitch conveyance line L2 and the arbitrary pitch conveyance line L2 overlap in parallel. A pull-in line L2' is derived from a part of the arbitrary pitch conveyance line L2, and when a self-propelled vehicle (to be described later) breaks down, it is pulled into this pull-in line L2° for repair.

The details of each part of the continuous conveyance device will be explained below with reference to FIGS. 2 to 9. Here, FIG. 2 is a front view of the main parts of the continuous conveyance device at the confluence point X, FIG. 3 is a view taken in the direction of arrow A in FIG. 2, FIG. 4 is an enlarged front view of the self-propelled vehicle, and FIG. is a view taken in the direction of arrow B in FIG. 4, FIG. 6 is a view taken in the direction of arrow C in FIG. 4, FIG. 7 is a view showing the structure of the front trolley and the catch trolley, FIG. FIG. 9 is a plan view of the switching mechanism.

The continuous conveyance device has a gate-shaped frame 1 erected on the floor, a frame 2 hanging downward from the gate-shaped frame 1, and guide rails 3, 3 provided at the lower end of this frame 2.
, 3 are engaged with rollers 5.5 of the hanger 4, and the hanger 4 is movable along the guide rail 3 while suspending and supporting the vehicle body W as a workpiece. The hanger 4 is equipped with a horizontal state maintaining mechanism 6, and a front and rear inner rod 7 is attached to the upper surface of this horizontal state maintaining mechanism 6, and is gripped by a self-propelled vehicle, which will be described later, at the front end of the front and rear inner rod 7 on one side. Projection piece 8
is installed.

Further, a trolley guide rail 9 is constructed in parallel with the guide rail 3 above the intermediate portion between the guide rails 3, 3, and a front trolley 10 and a rear trolley 11 are movably engaged with the trolley guide rail 9. 10 and the front end of the front and rear internal rods 7 are connected via a connecting rod 12, and the rear trolley 11 and the rear end of the front and rear internal rods 7 are connected through a connecting rod 13, and a free trolley 14 is also connected at appropriate locations. The free trolley 14 is also movably engaged with the trolley guide rail 9.

Further, a chain guide rail 15 constituting a constant pitch conveyance line L1 is arranged above the trolley guide rail 9, a drive chain 16 is arranged along this chain guide rail 15, and this drive chain 16 and the front trolley 10 By engaging these, the hanger 4 on which the workpiece W is placed is intermittently fed at a constant pitch.

As shown in FIG. 7, the front trolley 10 has a structure in which a lever 22 is swingably supported on an L-shaped plate 20 via a shaft 21, and the lever 22 and the plate 20 are moved forward. A gap 23 is formed between the lever 22 and the extending portion 20a of the lever 22, and the lower end of a driven projection 24 which is movable in the vertical direction is engaged with the rear end of the lever 22. The lever 22 is biased clockwise around the shaft 21 in the figure by the spring or its own weight, and as a result,
The passive protrusion 24 is located upwardly, and in this position engages with the drive protrusion 25 hanging down from the chain 16, so that the drive protrusion 2
5 pushes the front trolley 10 forward, thereby transporting the hanger 4 forward at a constant pitch.

Further, a stopper piece 27 is supported at the rear of the plate 20 via a shaft 26. This stopper piece 27 does not rotate rearward from the upright state shown in the figure, but can rotate forward against the spring. When the running drive chain 16 stops, the hanger 4 is moved due to inertia.
If the hanger 4 attempts to move forward, the stopper piece 27 will come into contact with the drive protrusion 25 and the forward movement of the hanger 4 will be blocked.

By the way, when one of the hangers 4 that are continuously conveyed approaches the preceding hanger 4, the rear trolley 11 of the preceding hanger 4 enters the gap 23 formed between the lever 22 of the front trolley 10 and the plate extension 20a. The protrusion 28 enters, the lever 22 is swung counterclockwise by the protrusion 28, and the passive protrusion 24 is moved downward.
The engagement with the driving protrusion 25 is released and the transmission of driving force from the chain 16 is cut off, thereby preventing the preceding hanger 4 from being pushed out by the succeeding hanger 4.

On the other hand, on the side of the chain guide rail 15 constituting the constant pitch conveyance line L1, there is an arbitrary pitch conveyance line L2.
A frame 30 constituting the chain guide rail 15 is disposed close to and parallel to the chain guide rail 15. As shown in FIG. 6, this frame 30 includes a pair of support plates 31.3.
1, and rails 32.32 facing each other are fixed to the lower ends of these support plates 31.31, and the 0-rails 34 of the self-propelled vehicle 33 are connected to these rails 32.32 so that they can run from the inside. It matches.

As shown in FIG. 1, a plurality of self-propelled vehicles 33 are provided on the arbitrary pitch conveyance line L2, and each self-propelled vehicle 33 is provided with a control box 35, so that the conveyance speed and stop position can be arbitrarily set. For example, as shown in FIG. 1, a self-propelled vehicle 33a
The self-propelled vehicle 33b can be stopped at 21 points, and the self-propelled vehicle 33b can be stopped at 22 points.

Further, the specific structure of the self-propelled vehicle 33 is such that a motor 38 for traveling is fixed to a plate 37 on which the rollers 34 are attached, and a pinion 39 rotated by the motor 38 is attached along the lower edge of the frame 30. A plate 41 is attached above the plate 37 so as to sandwich the rollers 34 so as to run at a desired speed by meshing with the rack 40. The plate 41 prevents falling during running.

Furthermore, a bracket 42 is suspended downward from the plate 37, and an auxiliary bracket 43 is attached to the lower part of this bracket 42, and a pair of left and right shafts 4 are installed between these brackets 42 and 43.
4.45 are rotatably supported, and the bases of clamp pieces 46 and 47 are fitted into splines carved at the bases of these shafts 44 and 45, and the shafts 4 protrude forward from the bracket 43.
Gears 48 and 49 that mesh with each other are key-fitted to the tips of 4 and 45. Here, the clamp piece 46°47
Elastic bodies 46a and 47a made of urethane or the like are provided on the opposing surfaces of the
is attached to reduce the impact when the clamp pieces 46 and 47 close.

On the other hand, a motor 50 for driving the clamp device is fixed to the lower surface of the plate 37, and the driving force of this motor 50 is transmitted to the gear 46 via a reducer 51 and a gear 52, so that the motor 50 rotates in forward and reverse directions. This allows the clamp pieces 44 and 45 to open and close.

By the way, as shown in FIGS. 8 and 9, near the confluence point X of the constant pitch conveyance line L1 and arbitrary pitch conveyance line L2, the driving force from the chain 16 is connected to the front trolley 10. A switching mechanism 60 for shutting off is provided.

This switching mechanism 60 is provided with a release cover 61 above the trolley guide rail 9 and below the lower end of the drive protrusion 25 of the chain over the section from the merging point X to the branching point Y. A bracket 62 is provided protruding from one side of the guide rail 9, a cylinder unit 63 is fixed onto this bracket 62, and a rod 64 of this cylinder unit 63 is connected to a base end portion of a lever 65.

This lever 65 is rotatably supported by a shaft 66 at a position immediately in front of the release cover 61 and at a position that is the same as or lower than the release cover 61.

In the above, the hanger 4 is conveyed along the constant pitch conveyance line L1 to the confluence point X with the arbitrary pitch conveyance line L2, with the driving protrusion 25 of the chain 16 and the passive protrusion 24 of the front trolley 10 engaged. When it comes, the 8th
As shown in the figure, the tapered surface of the upper end of the driven protrusion 24 comes into contact with the release cover 61, and the driven protrusion 24 is pushed down, disengaging from the driving protrusion 25 and slipping into the cover 61. At the same time or slightly before and after this, the cylinder unit 63 is compressed, and the lever 65 is moved to the ninth position.
Rotate counterclockwise in the figure. Then, the stopper piece 27 is pushed forward by the lever 65 and the passive protrusion 2
4, it enters into the release cover 61. By the above operation, the hanger 4 is separated from the constant pitch conveyance line L1.

Then, just before and after the separation of the knife 4 from the constant pitch conveyance line L1, the protruding piece 8 of the knife 4 is gripped by the clamp piece 46, 47 by the drive of the motor 50 of the self-propelled vehicle 33, and the motor 38 The hanger 4 is conveyed at an arbitrary pitch by driving.

In this manner, when the hanger 4 is transported to the branch point Y by the self-propelled vehicle 33, the passive protrusion 24 and the stopper piece 27 are pulled out from the release cover 61 and stand up. and,
At this time, when the clamp pieces 46 and 47 released the grip on the projecting piece 8 and waited, the driving protrusion 2 of the chain 16, which was traveling parallel to the hanger 4 on the constant pitch conveyance line L1,
5 catches up with the nozzle 4 and hits the stopper piece 27 of the front trolley 10 from behind, knocks the stopper piece 27 forward and enters between the stopper piece 27 and the driven protrusion 24, engages with the driven protrusion 24 again, and is fixed. Pitch conveyance line L1
Return to On the other hand, the self-propelled vehicle 33 is on the arbitrary pitch conveyance line L2.
and return to confluence point X again.

In the embodiment, an example is shown in which the driving force of the chain is transmitted to the hanger via the trolley, but the chain and the hanger may be directly connected.

(Effects) As explained above, according to the present invention, in contrast to a constant pitch conveyance line that conveys at a fixed pitch using the driving force of a chain, an arbitrary pitch conveyance line that conveys at an arbitrary pitch by a self-propelled vehicle is partially wrapped. Furthermore, since the chain and hanger (trolley) and the self-propelled vehicle and hanger can be connected and separated, the hanger (work) can be transported by the self-propelled vehicle at any pitch only in the lapped section. .

Therefore, it is possible to easily adapt to automated processes having different cycle times, and the automobile manufacturing process can be carried out extremely efficiently.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view of a continuous conveyance device according to the present invention, and FIG.
The figure is a front view of the main parts of the continuous conveyance device, Figure 3 is a view taken in the direction of arrow A in Figure 2, Figure 4 is an enlarged front view of the self-propelled vehicle, and Figure 5 is shown in the direction of arrow B in Figure 4. 6 is a view taken in the direction of arrow C in FIG. 4, FIG. 7 is a diagram showing the structure of the front trolley and the catch trolley, FIG. 8 is a front view of the switching mechanism, and FIG. 9 is a plan view of the switching mechanism. It is. In addition, 3 in the drawing is a hanger guide rail, 4 is a hanger,
8 is a projecting piece, 9 is a trolley guide rail, 10 is a front trolley, 11 is a rear trolley, 15 is a chain guide rail, 16 is a chain, 24 is a passive projection, 25 is a driving projection, 27 is a stopper piece, 33 is a self-propelled vehicle , 46.47 is a clamp piece, 6o is a switching mechanism, 61 is a release cover, 65
is a lever, Ll is a constant pitch conveyance line, L2 is an arbitrary pitch conveyance line, and W is a workpiece. Figure 5

Claims (4)

[Claims] (1) A part of the arbitrary pitch conveyance line conveyed by a self-propelled vehicle is brought close to the constant pitch conveyance line that conveys the hanger supporting the workpiece by the driving force of the chain so that the lines are parallel to each other, and A continuous conveyance device, characterized in that the constant pitch conveyance line is provided with a switching mechanism for connecting and disconnecting the driving force from the chain, and the self-propelled vehicle is provided with a clamp mechanism for gripping a part of the hanger. (2) The continuous conveyance device according to claim 1, wherein a trolley is connected to the hanger, and the trolley is connected to a chain via the switching mechanism. (3) The continuous conveyance device according to claim 1, wherein the arbitrary pitch conveyance line conveyed by the self-propelled vehicle is a circulation line. (4) The hanger that supports the workpiece is transported along the fixed-pitch transport line by the chain to the junction with the arbitrary-pitch transport line by the self-propelled vehicle, and at this junction the chain and the hanger are uncoupled. The self-propelled vehicle and the hanger are connected, and then the self-propelled vehicle transports the hanger to the branching point of both lines while accompanying the running of the chain.At this branching point, the self-propelled vehicle and the hanger are uncoupled and the chain and a hanger, and the hanger is returned to a constant pitch conveyance line.