JPH0355371B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a positioning mechanism for a moving body traveling along a defined conveyance path.

[Prior art]

For example, when assembling a certain product, it is widely used to assemble specific parts at several stations based on pallet conveyance means to obtain a finished product. In this case, if the pallet as a moving object completes one assembly process manually at each station, positioning at each station will not be necessary, or even if it is necessary, its accuracy will not be a problem. .

Incidentally, in recent years, automation has progressed in product assembly processes, and there is a strong tendency for work at each station to be performed by automatic machines known as industrial robots. Therefore, when each station in charge of product assembly sequentially completes a specific assembly process, the pallet on which the workpiece is placed must be fairly accurate in relation to the interaction between the automatic machine and the workpiece at each station. Positioning is required.

Therefore, in the past, when positioning a conveyed object such as a pallet as a moving object at each station, a braking force was generated based on magnetic attraction force.
Forced positioning using positioning pins is used.

[Problem to be solved by the invention]

However, the above-mentioned positioning and stopping means tends to cause vibration phenomena when positioning and stopping the conveyed object, and has the disadvantage that the loss time required for positioning is large. However, because the conveyed object is instantaneously mechanically positioned, the impact force is large.

[Means to solve the problem]

The present invention provides a positioning device for a movable body in a conveyance device that can shorten positioning time and improve positioning accuracy without impact by using a positioning drive means separate from a conveyance drive means for the movable body. There is a particular thing.

〔Example〕

The illustrated embodiment will be specifically described below. Figure 1 shows the principle of the transport system using a linear motor, excluding the positioning mechanism.
In FIG. 1, 1 is a conveyor, which is arranged along a desired conveyance route. A pallet 2 is placed on the conveyor 1 so as to be freely movable. 3 is a conductive plate material, which is joined to the bottom of the pallet. Inductors 4a to 4d generate a moving magnetic field in the direction of the arrow shown when energized, and in combination with the conductive plate 3 attached to the bottom of the pallet 2, linear motors (inductors 4a to 4d)
constitutes the primary, and the conductive plate 3 constitutes the secondary). 5
Stations a and 5b perform a predetermined work process while the pallet 2 is stopped. In addition, palette 2
The direction of movement of the inductors 4a to 4d is indicated by arrow Y.
Of these, inductors 4a and 4c are for braking, inductors 4b,
4d acts for power running.

On the other hand, FIG. 2 shows a specific positioning drive device illustrating the gist of the present invention, 6 is a stopper, and the pallet 2 is stopped at a certain position at a low speed or in a stopped state before reaching a predetermined position with respect to the station where it stops. It protrudes to a position where it detects when the object reaches the point and stops the movement of the moving object, and in the state shown by the dotted line, there is no room for contact with pallet 2, and it moves toward arrow Y2.
Allow pallet 2 to advance in the direction. The stopper 6 receives a command to stop the positioning of the pallet 2 by a limit switch or the like, is rotated to the position shown by the solid line, and is engaged with the pallet 2 for positioning. A cylinder 7 includes a rod 7a that expands and contracts based on hydraulic control, for example. The tip of the rod 7a is provided with an actuation piece 7b, and a stopper 7c that prevents rotation of the actuation piece 7b in the illustrated state. 7d is a spring whose both ends are fixed to the lower end of the actuating piece 7b and the support piece 7e fixed to the rod 7a, and is always operated so that the actuating piece 7b faces perpendicular to the running surface of the pallet 2. ing.

Reference numeral 8 denotes an engager, which is located within a height range that does not touch the pallet 2, and when the actuating piece 7b advances to a certain extent with the extension of the rod 7a, the actuating piece 7b
In the vertical state, the upper end portion that engages with the pallet 2 is located below the bottom surface of the pallet 2.

In the above configuration, the pallet 2 is first positioned at the station 5a based on the operation described later. Next, when the pallet 2 completes a predetermined process and moves to the station 5b, the inductor 4
Pallet 2 is created by generating a moving magnetic field in the direction of the arrow b.
The pallet 2 is moved toward the station 5b by the action of a linear motor caused by the eddy current generated in the conductive plate 3 placed at the bottom of the pallet. after that,
When the pallet 2 passes over the inductor 4b, the pallet 2 moves toward the station 5b based on inertia. The inductor 4c applies a braking force to the pallet 2 from a position where the inductor 4c and the conductive plate 3 of the pallet 2 at least partially face each other. Then, at a point close to the station 5b, the speed is extremely low or the vehicle is at a standstill.

The pallet 2 thus advanced to the station 5b is controlled to be stopped at a fixed position by the positioning drive means shown in FIG. That is,
Before the positioning of the pallet 2 to the station 5b is completed, a signal is obtained based on well-known means such as a limit switch (not shown), and the stopper 6 is set to the position shown by the solid line, and at the same time Accordingly, the actuating piece 7b, which was in an inclined state with respect to the running surface of the pallet 2 at the station 5b,
As the rod 7a is housed in the cylinder based on the above signal, the spring 7d changes its orientation in a direction perpendicular to the running surface of the pallet 2. Next, the actuating piece 7b drives the pallet 2 by the power of the cylinder 7, and engages the pallet 2 with the stopper 6, thereby strongly positioning the pallet 2. In this way, the pallet 2 completes its positioning by engaging with the stopper 6 without any loss time.

In this positioning of the pallet 2, the pallet 2 passes through a predetermined work process based on, for example, an industrial robot and moves to the next station (not shown). At this time, the stopper 6 changes to the position indicated by the dotted line, and the pallet 2 While obtaining a displaceable state, it is driven by the inductor 4d. When the pallet 2 is moved from the station 5b, the cylinder 7 is moved from its cylinder rod 7a at the same time.
In response to a command to stretch the pallet, the engaging element 8 inclines the actuating piece 7b with respect to the pallet running surface in preparation for positioning to the next station (not shown) adjacent to the station 5b.

Note that the above embodiment shows one specific example, and for example, the attachment end of the spring 7d on the rod 7a side does not necessarily need to be via the support piece 7e, and may be directly fixed to the rod 7a.
It can also be fixed so that the direction of the restoring force is opposite (stretching direction).

〔effect〕

As described above, in the positioning device for a movable body in a conveyance device according to the present invention, a linear motor mechanism is provided between the movable body such as a pallet and the conveyance path side as a driving means between each station, and the linear motor mechanism is provided between the movable body such as a pallet and the conveyance path side. This is carried by thrust, and the positioning is performed by a mechanical forced positioning mechanism when the moving body is at very low speed or in a stopped state. With this configuration, the time required from the start of the positioning operation of the moving body to the completion of the positioning operation is significantly shortened as there is no vibration phenomenon during positioning compared to the conventional non-contact means based on the magnetic method.

On the other hand, unlike conventional positioning pins, there is no room for applying a considerable impact to the moving body during positioning of the moving body. That is, the present invention has both the non-impact characteristic during positioning of the conventional magnetic method (non-contact positioning means) and the positioning response characteristic of the positioning pin.

In addition to the above features, according to the positioning mechanism shown in Fig. 2, the distance between the bottom of a moving object such as a pallet that receives driving thrust based on the linear motor mechanism and the flat side of the conveyance path that opposes it is small. It has the feature that it can be easily applied even in the case of

[Brief explanation of drawings]

FIG. 1 is a front view showing an outline of the conveyance system, and FIG. 2 is a principle diagram showing a positioning mechanism which is the gist of the present invention. DESCRIPTION OF SYMBOLS 1... Conveyor, 2... Pallet, 3... Conductive plate material, 4a-4d... Inductor, 5a, 5b... Station, 6... Stopper, 7... Cylinder, 7b... Operating piece, 8... Engagement element.

Claims (1)

[Claims] 1. A moving body for positioning control is positioned at one or more stations located along the conveyance path, and then driven based on the thrust of a linear motor mechanism provided between the moving body and the conveyance path. A positioning device for a movable body in a conveyance device, comprising the components described in the following items (A) to (F). (A) A first part that protrudes to a position that detects when the movable body reaches a certain position in a low speed or stopped state before reaching a predetermined position relative to the station where it needs to stop, and prevents the movable body from proceeding. Stoppa. (B) In the above station, a cylinder consisting of a cylinder body that does not touch the moving body and whose longitudinal direction is in the direction of movement of the moving body, and a rod that is extendable and retractable from the cylinder body in a direction opposite to the direction of movement of the moving body. . (C) rotatably supported by the tip of the cylinder rod, engaged with the movable body in a state perpendicular to the running surface of the movable body in the station, and engaged with the movable body in the process of storing the cylinder rod into the cylinder body; An actuating piece that brings the moving body into pressure contact with the first stopper. (D) A second stopper fixed to the cylinder rod, which restricts the actuating piece to be perpendicular to the running surface of the movable body in the station when the actuating piece is engaged with the actuating piece. (E) A spring having one end fixed to the actuating piece and the other end fixed to the cylinder rod either directly or via a support piece, and having a restoring force to engage the actuating piece with the second stopper. (F) A travel path for the movable body, provided near the tip of the cylinder rod extending from the cylinder body, so that the actuating piece does not obstruct the passage of the movable body while the cylinder rod extends from the cylinder body. The engager is tilted with respect to the moving body running surface in the station.