VISION SYSTEMS & GUN TRIGGER PACKAGES

Finishing automation uses several gun mover technologies to coat parts. Robot arms are a popular method of carrying the spray gun around the part. The robot control contains one or more preprogrammed paths and, when the part reaches the spray booth part detection switch, the robot executes the path and coats the part. If the line coats more than one part the robot systems requires some method to identify which path is required to coat the part.

Simple systems utilize an operator to manually select the part number from the robot teach pendent. Human/Machine Interface Terminals (HMI), RFID tags, and Computer Vision System are popular technologies to automatically provide the robot control with the correct path number.

Autoquip manufactures and integrates most Part Identifications systems technologies. Our Flagship technology is a Vision Camera System with an extremely simple part teaching operator interface.

Autoquip Vision System offers a self-learn mode where a number of identical parts are introduced to the system and the Vision Computer records pertinent information about the part features and the subtle variations typical with identical parts on a moving line. On playback the Vision Camera/Computer system analyzes the image and reports to the painting robot control the correct path number or if the part is not found a “No Read” alert/alarm.

The Vision System provides several advantages over HMI and RFID technologies. The biggest advantage is the system requires no human intervention. Both the HMI and RFID require an operator to first identify the part and either correctly enter the data on the HMI terminal or correctly program the RFID tag. The Vision System will automatically not paint a part not hung correctly or a paint fixture too bent for a good paint finish. The Vision System also has a better chance of stopping an atomizer crash. The Vision System can also detect color change flags and signal automation to sequence materials properly.

Vision Systems consist of one or more Vision Cameras, Vision Computer, Lighting Source, and Part Present Sensor. The system is normally installed on a flat area of the painting conveyor. When a conveyor hook activates the Part Present Switch the Vision Camera(s) and Lighting Source synchronize to produce a back lit image (shadow). The shadow image reduces image errors due to color and gloss. The image computer analyzes the shadow and processes a match algorithm to determine the best fit. User defined tolerance limits verify whether the best fit results qualify for a match.

The Autoquip Vision Computer includes a Status Terminal. During programming of the part the Status Terminal provides recorded image information and verifies storage of the image for later playback. In production, the Status Terminal outputs the match information and tolerance differences.

Autoquip’s Trigger Packages deliver a simple method of identifying the presence of a part on a moving conveyor away from the spray zone and electronically following the part on the conveyor through the spray zone triggering spray guns at the appropriate time and place.

The advantages of the spray package over sensing the part in the spray zone include, reduced overspray on the part sensor, reduced maintenance, one sensor for multiple spray guns, and more control on triggering.

Triggering packages are installed on all types of conveyors including, Chain On Edge (COE), Flat Top, Floor, Enclosed Track, Overhead, and Dual Strand. One or more photocells are commonplace for part sensing. More sophisticated light curtains and vision cameras can also be incorporated. A conveyor encoder signal is used to track the part. Low cost PLC controls provide the shift register memory, and a small Human/Machine Interface Terminal (HMI) allow for setup programming reporting status.

The conveyor drive mechanism turns the encoder providing scaled conveyor movement. A part traveling down the conveyor breaks the photocell beam signaling the PLC to store the part location in the shift register memory. The HMI provides the necessary programming to virtually align each spray gun on the conveyor and any lead or lag to compensate for mechanical delay in the trigger solenoid or spray gun.