Rotary carousel robots for seat finishing

One of the most difficult pieces of furniture to finish is the chair. The most commonly used method of staining, varnishing or painting chairs is spraying. This is the only way to cover even the most hidden places. Unfortunately, spraying is the application method with the highest wastage, and for chairs it is higher than for other pieces of furniture. The challenge for spray gun manufacturers has always been to find a way to minimize losses. Applying airmix or in electrostatic system greatly reduce losses to material transfers per part in excess of 90%. But material losses are not the only problem with seat finishing. Their shape is labor-intensive, which leads to lower productivity and sometimes to film defects. These problems can be solved by using spraying robots. The most advanced robots in terms of the modern technologies included are anthropomorphic robots.

What is an anthropomorphic robot

The anthropomorphic robot is an identical copy of how humans work. The robotic arm is similar to a human arm, with 6-axis movement. To make those complex movements, the robot has 3 points of articulation that replicate the shoulder, elbow and wrist joints. The spray gun is mounted at the end of the robotic arm so that the spray can reach the most hidden areas just like hand spraying.

Incidentally, one of the ways in which the robot can be "taught" the movements to perfectly paint a chair, a complicated piece of furniture, even a violin, is by literally copying human movements. When the robot is on the learning program, the operator grasps the gun at the end of the robotic arm and routinely sprays the object so that all parts are perfectly covered.

The chosen "path" is calculated in such a way as to achieve maximum quality with minimum time and consumption. All movements made by the operator remain in the "mind" of the robot transformed into a program. The parts will be finished identically without the risk of the hand getting tired, moving faster or slower and resulting in a thinner or thicker layer of paint or other such problems that occur naturally with manual spraying. You can see how an anthropomorphic robot "learns" human movements in the movie at the end of the article.

What is a rotating carousel robot and what advantages it comes with

We are also talking about anthropomorphic spray robots, but for the sake of simplicity I'll simplify the name a bit. The rotating merry-go-round with which the robotic arm is combined is similar to a circus carousel. Around the spraying robot there is a circular mobile system with several movable arms on which the objects to be finished are placed. This system is part of the robot and rotates, bringing the objects one by one to the robotic arm doing the spraying. The arms of the carousel have the ability to rotate, raise or lower the parts. After the first object is completely covered, the system rotates again bringing the next object in and taking the first one out of the gun's reach. All operations are programmed and stored in the robot's computer.

The advantage of the rotary carousel is the limited space in which it operates and the possibility to be serviced by a single operator. Typically the lines for finishing chairs are long, with chairs hanging from chains that go through different stages of the process and require a lot of space. Using the rotating carousel robots the space is greatly reduced, being basically a 1.5-2 m radius circle around the robotic arm.

Reducing the required staff to one operator is again a big advantage. Especially now, when labor shortages are a big problem in all areas, not just woodworking. The operator can replace the finished chair with a blank one when he reaches the position opposite the spray point. He has time to operate the gun, during which the carousel is stationary.

The use of anthropomorphic robots is not restricted to chairs

Chairs are the ones most often used as an example because they are some of the most difficult pieces of furniture to finish. But anthropomorphic robots can be used for most objects that are spray-finished.

They are less commonly used for simple panels. In these cases finishing can be done very well with spray robots that move in the x-y axis. But for more sophisticated pieces of furniture or musical instruments, the use of anthropomorphic robots ensures increased productivity and a consistent and very good quality of finish.

I found finishing violins with this type of robot very interesting. In the past I've worked with Hora musical instrument factory in Reghin and I often saw violins, violas, guitars and other instruments being finished. I always admired the craftsmanship of the people finishing them, but I realized how hard it is to do it for 6 hours holding the violin or guitar in one hand and the spray gun in the other. A robot like this solves the problem and can even work for 24 hours and achieve the same quality.

Epistolio - the robot already in Romanian factories

About Epistolio robots I told you something in September 2018on the occasion BIFE SIM Fair, when the Italian manufacturer announced its official entry on the Romanian market alongside Falk Consultingdistributor of spray guns Sames Kremlin. Now there are already factories in the country working with them, Sortilemn Gherla being just one example.

These spraying robots can be used for coating wood, metal or plastic with varnishes and liquid paints, powder coating of metal objects, enameling of ceramic objects, sanding or sandblasting with abrasive powders, etc. In any field where manual spraying is practiced, the robots will increase productivity while maintaining a high quality finish.

The range Italian producer Epistolio has entered the Romanian market is MRK. One of the most performing robots recommended to chair manufacturers is the Epistolio MRK 6.1. The carousel has 3 arms on which the chairs to be finished will stand. They are made with lightweight materials so inertia is greatly reduced. Furthermore, the weight of the arms is counterbalanced with pneumatic cylinders used to reduce the influence of the paint getting into the paths on the 3 arms.

The "hand" wrist of the robotic arm is designed to allow movement in all directions independent of the tilt of the carousel arms. This allows painting to be carried out very well, with the spray easily reaching hard-to-reach areas.

These spraying robots are equipped with all kinds of programs and systems that make them easy to operate and achieve the expected results. If you want an Epistolio robotic spraying system it is best to contact Falk Consulting. You will get all the information you need to make an informed choice.

I now let you watch the movie of epistolio robots at work. You will see that they finish other objects very well, not just chairs. If you think it is of interest to others, feel free to share. And if you have any questions or comments, leave them below in the dedicated area.