Introduce a self-developed automatic loading and unloading manipulator for special equipment, discuss the application of vacuum chuck technology, the selection of suction cup material, the calculation of suction force, the selection of vacuum degree, vacuum pump, etc., as well as the automation of automatic programs and robots. Handling process.
In recent years, with the continuous expansion of the production scale of Tyson Risheng Company, many imported advanced equipments have been introduced. The handling manipulator formed by the sponge suction cup is applied in the automatic sanding and blanking machine of the plate sanding and edge banding machine. The handling robot occupies a small space, and the wooden door for carrying a large area is flexible and reliable, and the whole device is fully automatic and has high work efficiency. In order to improve the quality of the products, expand the scale of production, and at the same time, the original imported equipment has shortcomings such as insufficient suction of the suction plate when the air pressure is insufficient. In the beginning of 2015, based on the original equipment, we successfully developed a handling manipulator consisting of a sponge suction cup.
1. Specifications for manipulators moving wooden door panels
Thickness 20 ~ 35 mm; length 2000 ~ 3050 mm; width 868 ~ 1000 mm; maximum mass 50 kg.
2. Mechanical structure of the manipulator and its working process
The vacuum system is mainly composed of a high pressure blower, a sponge suction cup, a vacuum soft transfer tube, an electromagnetic reversing valve, a vacuum switch, a vacuum filter and the like. The suction cup bracket is mainly composed of a steel frame, two aluminum profiles and two sponge suction cups mounted thereon. The lifting system is driven by the motor, reducer and drive chain to raise and lower the suction cup bracket. The robot is shown in Figure 1.
The rotating system relies on the motor on the column and the base, the reducer, and the transmission gear to drive the suction cup bracket to rotate.
3, vacuum suction cup selection calculation
3.1, the choice of vacuum
For the secondary handling technology, low vacuum can meet the requirements. Typically, the low vacuum pressure ranges from 100 Pa to 1 standard atmosphere. For harsh environments such as handling wooden doors, external vacuum generators (high pressure blowers) are purchased. The vacuum is usually between 20,000 and 40000 Pa. If the vacuum does not meet the requirements, the suction or filtration device needs to be cleaned.
3.2, the choice of sponge suction cup
This equipment must first determine the sponge suction cup. If the product size is different or there is leakage, we need to select the check valve body. If the action needs to be reversed, we need to select the throttle valve body.
4, robot automatic control program
The automatic control program uses the S7-200 type program controller manufactured by Siemens. When the robot starts working, first turn on the vacuum pump. The loading process is as follows:
(1) The suction cup bracket drives the two rows of suction cups to descend rapidly. After the adjustable photoelectric switch detects the sheet material, the slow speed drops to 50mm, the suction cup touches the sheet material, and at the same time, the suction cup bracket touches the limit switch;
(2) The two-way three-way solenoid valve starts to operate, so that the suction cup is connected to the vacuum for about 1~2s. When the vacuum switch detects the vacuum value of 60~80 kPa (suction plate sample parameter), confirm that the sheet material has been sucked up. ;
(3) Quickly raise, touch the first limit switch, the suction cup turns to slow motion, touch the second limit switch (about 200 mm at this time), stop in place;
(4) Rotate quickly, touch the first limit switch, the suction cup turns to slow motion, touch the second limit switch, and stop in place (total 180°);
(5) Rapidly descend, touch the first limit switch, the suction cup turns to slow motion, touch the second limit switch, and stop in place (about 200mm);
(6) The electromagnetic reversing valve is reversed to amplify the gas, the suction cup is disengaged from the sheet material, and falls on the main roller table, and the photoelectric switch on the roller table sends out a signal;
(7) The suction cup bracket drives the suction cup to rise rapidly, and the slow speed is in place (about 200 mm high);
(8) Rotate 180° quickly and slowly. At this point, an automatic loading action is completed.
The programming can realize the repeated feeding of the cycle, or can be manually controlled, and the single-time automatic random feeding or the jog can stop the suction cup bracket at any position. In the rear position of the limit switch such as ascending, descending, rotating, etc., an alarm limit switch is installed as a standby switch to prevent the stop of the stop.
When cutting, the manipulator's action procedure is similar to that of loading. The difference is that the starting position is to take the material from the main roller, and finally put the material on the rack.