The use of robotics has allowed Ricoh to manufacture its toner cartridges more efficiently
Ricoh’s approach to automation and efficiency was demonstrated when it began building a new production line for the colour toner cartridges used in one of its office machines. The company began by investigating a way of using industrial robotics to make manufacturing the toner cartridge shutters a more simple process. Ricoh initially approached Evershed Robotics, who suggested using a combination of a Toshiba Machine TH650 SCARA robot and a Toshiba Machine Cartesian robot supplied by TM Robotics to work with their six bowl feeders and a rotary index table.The objective of the automated element of the line is to assemble a shutter to open and close the cap on the cartridge. The shutter itself contains five parts which have to be assembled.
To meet the production demands Ricoh needs to assemble the shutter in 7.5 seconds and to do this the company uses a rotary table surrounded with associated automated equipment to assemble the device. After the parts are removed from it, they are stacked in trays before being moved to the next element of the assembly line. Control is managed by an Omron PLC, which communicates with the Toshiba Machine SCARAs.
Because some of the seals can be easily dislodged during the process, Ricoh needed a precise system and the SCARA robot uses sensitive parallel grippers to pick a raw body from a bowl feeder and place it on the table. Then, from the next unit clockwise around the table, it picks up a completed assembly. This assembly is then rotated through ninety degrees so it is in the correct position to be packed and secured.”
The packing trays are located on a Cartesian robot arm, held there by a vacuum attachment, and the 72 units are arrayed in rows of eight by nine. This robot arm presents the tray to a common position and it stays there until it is completely loaded. The tray is then replaced back into the magazine from which it came. The Cartesian arm then selects the next tray down.
The magazines are replenished manually and the full trays are taken out and stored or moved onto the next step of the process. To ensure personnel safety, there are a series of light guards to stop the operator opening the door. If the door is opened, the robot is prevented from entering the area by the light guards. Because the throughput of the system is so high, reliability is clearly vital in the application. There is a constant demand for cartridges and a failure in production could lead to problems in the supply chain, so to avoid such problems, Ricoh UK Products keeps a stock of finished components in case of system break down.
The installation of the system was said to be straightforward, with mechanical installation taking just half a day. According to Ricoh, wiring and testing took nearly a week and further developments in reducing cycle time and improving system efficiency accounted for no more than a couple of additional days. TM Robotics says that the system has more than paid back its installation time in improved efficiency already.
“Without automation, the cost of doing this job manually would be very high, and the quality of the assembled parts could not be guaranteed,” explains Ricoh engineer Matt Talbot. “Also, because it’s so intensively repetitive, this kind of job is made for automation. However, while it was cost that originally prompted us to invest in robotics, we have since become keen advocates of their simplicity, reliability and profitability. So much so that we’ve expanded other areas of the line and added three other SCARA robots at the heart of separate systems.”
Commenting on the success of the application, Nigel Smith, md at TM Robotics observes “I believe that Ricoh have been so successful with their industrial robot installations because the company immediately grasped that it’s about making manufacturing easier, not more complex. Once this mental shift has been made, any manufacturer could reap benefits similar to those seen at Ricoh. It’s just a case of taking the first step into industrial robotics.”