Sorting & Distribution Line PLC Programming

In this advanced PLC logic, detect different part sizes and sort them as per box sizes and place them in the trays.

Contents

The parts are nothing but different size boxes such as small, medium, and large. The robot places different size boxes randomly on the conveyor. Then the system detects the box size and moves to the respective conveyor and places them in the respective trays.

Sorting & Distribution Line PLC Programming

The below simulation shows the sorting and distribution line system operation.

Inputs and Outputs

Type	Device No.	Device name	Operation
Input	X0	Starting point (Supply)	ON when the part is detected.
Input	X1	Upper	ON when the part is detected.
Input	X2	Middle	ON when the part is detected.
Input	X3	Lower	ON when the part is detected at the right end.
Input	X4	Sensor	ON when the part is detected at the right end.
Input	X5	Sensor	The conveyor moves forward when Y1 is ON.
Input	X6	Detect part	ON when the part is detected in front of the pusher.
Input	X10	Starting point (Unload)	ON when the unloading robot is at the start point.
Input	X11	Part on table	ON when the part is on the table.
Input	X12	Robot operation finished	ON when the robot operation is finished.
Output	Y1	Conveyor forward	The conveyor moves forward when Y2 is ON.
Output	Y2	Conveyor forward	Moves toward the front when Y3 is ON.
Output	Y3	Sorting wing	The conveyor moves forward when Y4 is ON.
Output	Y4	Conveyor forward	The conveyor moves forward when Y5 is ON.
Output	Y5	Conveyor forward	Extends when Y6 is ON and retracts when Y6 is OFF. The pusher cannot be stopped in the mid-stroke.
Output	Y6	Pusher	The robot moves part to tray when Y7 is ON. A process cycle begins.
Output	Y7	Unload command	The robot moves the part to tray when Y7 is ON. A process cycle begins.
Output	Y10	Red	Lit when Y10 is ON.
Output	Y11	Green	Lit when Y11 is ON.
Output	Y12	Yellow	Lit when Y12 is ON.

Program Description

Initiating the push button PB1 (X20) on the control panel triggers the Supply command (Y0), thereby setting the robot in motion for moving the object.

Once the robot has completed its task of moving the part and reverting to its original position, the Supply command (Y0) is deactivated. Activating the Supply command (Y0) propels the robot to provide a part.

Activating the switch SW1 (X24) on the control panel instigates the conveyors to proceed forward. Conversely, deactivating the switch causes the conveyors to halt.

Conveyor-carried parts of varying sizes, namely large, medium, and small, are sorted by input from the Upper (X1), Middle (X2), and Lower (X3) sensors and delivered to designated trays.

Large parts are directed to the rear conveyor when the Sorting wing (Y3) on the split conveyor is activated, followed by the part being transported on the conveyor and eventually descending from the right edge.

Medium parts are led to the front conveyor when the Sorting wing (Y3) on the split conveyor is deactivated and subsequently transferred to the tray by the robot.

Small parts are routed to the rear conveyor upon activation of the Sorting wing (Y3) on the split conveyor. Once the Detect part sensor (X6) in the split conveyor is activated, the conveyor is brought to a halt and the part is nudged onto the tray.

When the Robot detects a part on the table (X11), the Unload command (Y7) is activated. Once the robot finishes its operations, indicated by the Robot operation finished (X12) status turning on (which happens when a part is deposited on the tray), the Unload command (Y7) is deactivated.

Provided the switch SW2 (X25) on the control panel remains activated, an automatic supply of a new part occurs under the following conditions:

When the robot initiates the transportation of a medium part.
When a small part is added to the tray, or a large part descends from the right edge of the conveyor.

The display lights flash in the following manner: