JPH0217798Y2 - - Google Patents

Description

[Detailed explanation of the invention] Industrial field of application This invention uses a robot to load unprocessed workpieces stacked in multiple stages on a pallet of a feeder one by one into a processing machine, and to load processed workpieces onto a processing machine one by one. This invention relates to a work feeder that prevents workpieces from shifting, collapsing, etc., which are inconvenient for robot work, when stacking workpieces in multiple stages on a pallet.

Conventional technology A robot is combined with a conventional work feeder that connects and circulates a large number of pallets on which workpieces are placed.
When performing automatic operations such as gripping individual workpieces with a robot hand and mounting them on a processing machine, and then taking out the machined workpieces from the processing machine and stacking them on another pallet, the work feeder moves intermittently in the forward and reverse directions. Since starting and stopping are repeated, there is a risk that the workpiece may become misaligned on the pallet. If misalignment occurs, it becomes difficult for the robot hand to grasp the workpiece, so conventionally, a rubber plate with high friction force or a frame surrounding the workpiece is installed on the pallet to prevent misalignment or to reduce the feeder transfer speed. was used. However, although the former method can prevent the misalignment of the workpieces on the bottom layer, it cannot prevent the misalignment of the workpieces above it, and the latter method has the disadvantage that the cycle time for replacing workpieces becomes longer, reducing production efficiency. .

Problems to be solved by the invention This invention eliminates the above-mentioned drawbacks of a work feeder that works together with a robot, and also eliminates the labor required to align and stack workpieces when placing unprocessed workpieces on the work feeder. The purpose is to propose a work feeder.

Means for Solving the Problems In this invention, a workpiece alignment rod is guided and supported vertically through holes provided in the workpieces in each of the pallets of the conveyor that horizontally circulates the workpiece transfer pallets. A cam groove for raising and lowering the workpiece alignment rod is provided in the conveyor frame along the horizontal movement locus of the robot. The workpiece alignment rod is continuously raised to a predetermined height above the load surface from the position to the pallet stop position before and after the pallet stop position, and thereafter the pallet alignment rod is held at the predetermined height. do.

Function The circulation path of the conveyor, which connects a large number of pallets on which workpieces are stacked, has a workpiece loading and unloading position where the robot takes out unprocessed workpieces from the pallet and stacks processed workpieces on the pallet, and a workpiece loading and unloading position where the robot takes out unprocessed workpieces from the pallet and stacks processed workpieces on the pallet. There is a workpiece exchange position where a machined workpiece is taken out from the pallet and an unprocessed workpiece is placed in its place. Then, the conveyor is rotated forward and reverse to alternately move the empty pallet and the adjacent pallet carrying unprocessed workpieces to the workpiece loading/unloading position, and the robot hand takes out the unprocessed workpieces one by one and places the processed workpieces in the empty pallet. They are piled up on the pallet. When this operation is repeated and the pallet carrying unprocessed workpieces becomes an empty pallet, the conveyor is advanced by one pallet pitch and the above operation is repeated again.

Therefore, all of the workpiece alignment rods on the pallet located between the front and rear pallet stop positions adjacent to the workpiece loading/unloading position and the workpiece exchange position are in the raised position, and the rods pass through the holes of all the workpieces on the pallet to align the workpieces with the workpieces on the pallet. This prevents the workpiece from shifting due to reversal, and the workpiece alignment rod is lowered to the pallet loading surface at the workpiece loading/unloading position, which does not prevent the workpiece from shifting, but it does prevent the workpiece from shifting between the workpiece loading/unloading position and the pallet stop position next to it. In between, the work alignment rod penetrates through the holes of at least some of the stacked works on the pallet, so that the displacement of the works is reduced accordingly.

Embodiment In FIG. 1, a work feeder 1 is provided with a conveyor chain driven to rotate endlessly in the center of an oval frame 2, and a wheeled pallet 3 connected to the chain at one end with equal pitch. The robot advances along the oval path on the frame 2 in the direction of the arrow while reversing forward and backward by the pitch. The pallet 3 is stopped at both ends of the long axis of the oval shape, and at the workpiece exchange position A at one end, the processed workpieces M are taken out from the pallet and a predetermined number of unprocessed workpieces M are piled up, and at the other end, the machined workpieces M are taken out and the unprocessed workpieces M are piled up. It is assumed that the robot attaches and detaches the workpiece at the workpiece attaching and detaching position B.

The robot 4 has a lifting device in a base 5 fixed to the frame 2, and has a lifting device in the long axis direction (X direction).
The movable base 6 is guided and supported horizontally.
A rotating shaft (R-axis) is provided that projects in the direction of movement, and the base end of the arm 7 is fixed to this rotating shaft. Attach wrist 8 and hand 9 to arm 7, and attach two pairs of fingers 1 to the tip of hand 9.
0a and 10b are provided. Hand 9, fingers 10a, 10b
can be indexed and rotated in 90 degree increments around the wrist central axis 11.

The fingers 10a and 10b are attached so that the central axes of the workpieces M they grip are aligned with each other and also coincide with the X axis at one index position. finger 1
0a stops at a point a directly above the workpiece loading/unloading position B due to the indexing rotation of the wrist 8, the rotation of the arm 7 around the R axis, and the movement in the X axis direction, and is then lowered by the lifting device. Grip the unprocessed workpiece M on the pallet 3 that is stopped at the workpiece loading/unloading position B.

Next, the arm 7 returns to the position shown in the figure by the reverse operation, and after the wrist 8 has rotated 180 degrees, the arm 7 rotates in the r direction by the required angle, and the workpiece M is placed in the chuck 1.
2 to point b on the central axis. Next, mobile platform 6
moves backward and loads the workpiece M into the chuck 12.

Along with the above operation, the finger 10b also operates in substantially the same manner to take out the processed work M from the chuck 12 and place it on the pallet 3 at the work loading/unloading position B. Unprocessed workpiece take-out operation of finger 10a and finger 10
The operation of taking in the machined workpieces in b is performed alternately, and during that time the pallet 3 on which the machined workpieces are placed is
and the pallet 3 on which the unprocessed workpiece is placed are respectively the workpiece loading/unloading position B and the downstream pallet stopping position C.
and between the work loading/unloading position B and the pallet stopping position D upstream thereof. This forward and reverse movement is repeated as many times as the number of workpieces stacked on the pallet, and when pallet 3 on which the unprocessed workpieces are placed becomes an empty pallet, the conveyor advances by one pallet pitch and moves to the next pallet on which the unprocessed workpieces are placed. 3
Works are transferred between the pallet and the empty pallet in the same manner as above.

A cam groove 13 is provided on the upper surface of the frame 2 along the movement locus of the workpiece placement center of each pallet 3, and a center hole 14 is provided in the workpiece placement center of each pallet 3 so as not to interfere with the finished dimensions of the workpiece M. A workpiece alignment rod 15 is guided and supported so as to be freely raised and lowered, and its lower end is brought into contact with the cam surface 16 of the cam groove 13. As a result, the upper end of the workpiece alignment rod 15 is aligned with the pallet 3 at the workpiece loading/unloading position so as not to interfere with the robot's grasping of the workpieces.
It descends to the loading surface of the pallet, and continuously rises to a height that penetrates the holes 14 of a predetermined number of stacked works M on the pallet while going from the work loading/unloading position B to the pallet stopping positions C and D. From this point, the workpieces can be replaced. Up to position A, this rising height is maintained using the upper surface of the frame 2 as a cam surface.

That is, the workpiece alignment rod 15 penetrates through the holes 14 of all the unprocessed workpieces on the pallet 3 between positions A and D, and passes through the holes 14 of some of the workpieces between positions D and B.
At position A, it is convenient for aligning unprocessed workpieces M when stacking them on a pallet, and between positions A-D-B, the workpieces on the pallet can be easily aligned even though the workpiece feeder frequently rotates in the forward and reverse directions. Misalignment of the unprocessed workpiece can be almost completely prevented.

Note that it is effective to attach a resin sheet to the cam surface 16 or to attach a roller to the lower end of the workpiece alignment rod 15 so that the workpiece alignment rod 15 can slide smoothly on the cam surface 16.

Effects of the invention This invention has the above configuration, and since the workpiece does not shift in position, it reduces the robot's workpiece gripping errors.
It has the effect of increasing the number of workpieces stacked on the work feeder, increasing the number of workpiece stocks on the work feeder, and enabling high-speed operation of the work feeder.It also makes manual work of stacking unprocessed workpieces on the pallet faster and easier. It has a tightening effect.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of one embodiment of the present invention, and FIG. 2 is a developed longitudinal sectional view along the cam groove of FIG. 1. 3...Pallet, 13...Cam groove, 14...
Hole, 15... Work alignment rod, B... Work loading/unloading position, C, D... Pallet stopping position.

Claims (1)

[Scope of utility model registration request] A workpiece alignment rod that vertically passes through holes provided in the workpieces of each pallet of the conveyor that horizontally circulates the workpiece transfer pallets is guided and supported so as to be freely raised and lowered, and the workpieces are moved to the conveyor frame along the horizontal movement locus of the workpiece alignment rod. A cam groove for raising and lowering the alignment rod is provided, and the cam groove lowers the workpiece alignment rod to the loading surface of the pallet at the work loading/unloading position of the pallet to the robot, until reaching the pallet stopping position before and after the work loading/unloading position. The work feeder is characterized in that the workpiece alignment rod is continuously raised to a predetermined height above the load surface, and thereafter the pallet alignment rod is held at the predetermined height.