Diagram of hydraulic system of industrial robot

The hydraulic system of the robot (Figure 3) includes a hydraulic station, hydraulic cylinders, linear electrohydraulic step drives (EGSP) of the slider, arms and carriages, as well as hydraulic panels and hydraulic distributors. Hydraulic station 1 is used for power supply of EGShP, as well as drives of mechanisms of gripping rotation, head rotation and part clamping, which allows to automatically change capacity of M1 pump at constant pressure in pressure and power lines. The hydraulic station also performs functions of oil cooling and prevention of oil drain from the hydraulic system during shutdown. The carriage drive 5 consists of two hydraulic motors 4, the next pair and a low power step motor 6 and operates as follows. When the signal is transmitted to the step motor M5, its shaft through the screw gear displaces the slide valve of the hydraulic distributor, connecting the pressure and drain lines with the corresponding cavities of the hydraulic motors. Shafts of hydraulic motors are connected through reduction gear with rack gear moving carriage along monorail. Hydraulic motors 4, 17 are connected in such a way that moments on their shaft are directed towards each other, which ensures constant pressing of gear teeth to rack teeth, i.e. selection of play in rack gear. When the hydraulic motor rotates, its shaft rigidly connected to the slide valve of the servo pair tends to return the slide valve to the initial position, thus performing feedback on the position. Drives 2 and 3 of carriage and hand movement consist of step motors M3 and M4, servo pair and hydraulic cylinder, in the rod of which the screw feedback mechanism is built in. When the signal is transmitted to the stepper motor, its shaft displaces the slide valve of the hydraulic distributor through the screw transmission, opening the oil passage in the hydraulic cylinder cavity. Translational movement of hydraulic cylinder piston through screw gear is converted into rotation of screw and through gear gear and screw pair into axial movement of slide valve, forming feedback on position. Check valves are provided to prevent accidental sliding of the units when the hydraulic system is disconnected. The head is turned by 90 ° by hydraulic cylinder (7) through zubchatoreyechnuyu transmission with braking at the end of travel. Hydraulic cylinder is controlled by hydraulic panel (11). At actuation of electromagnet (8) of hydraulic distributor (10) the head turns to vertical position, at actuation of electromagnet (9) - to horizontal position. On the robot head there are hydropanels 14 and 18 for controlling the grip rotation and the part clamp. Rotation is performed by hydraulic motor 17 when commands are supplied to hydraulic distributors 13 and 16 with electric control. When electromagnet 12 is switched on, oil under pressure enters LH cavity of control hydraulic cylinder. If the electromagnet 15 is disconnected, the right chamber of the hydraulic cylinder is connected to the drain and its piston moves to the extreme right position, moving the slide valve of the throttling hydraulic distributor with the help of the lever and opening the oil passage from the hydraulic motor cavity. The other end of the lever constantly contacts the cams installed on the robot head so that when the head is rotated by the desired angle, in this case to the extreme right position, the lever returns the spool of the throttling hydraulic distributor to the middle position and the hydraulic motor stops. When electromagnet 15 is switched on and electromagnet 12 is switched off, fluid under pressure enters the right chamber of control hydraulic cylinder, its left chamber is connected to drain, piston is set to the left position and hydraulic motor turns head to the left till corresponding cam. When both electromagnets 12 and 15 are switched on, both chambers of the control hydraulic cylinder are connected to the pressure line, and due to the difference in areas, the piston will become in the middle position determined by the bushing stop. The hydraulic motor will turn the head to the middle cam. The grip drive is designed to work with double and single grip. Depending on the type of grip, the crane distributor 18 on the hydraulic panel is manually set to position 1 or 2.During operation with single lock-on, control is performed using hydraulic distributor 20. When the electromagnet 19 is switched on, the grip is expanded, when it is turned off, the blank is clamped by the grip. The check valve is built into the hydraulic panel to prevent a sharp grip clamp in case of an emergency pressure drop in the system. When working with a double grip, the command to open each grip is supplied by turning off the electromagnet 19 or 21. When both electromagnets are on (or off), the grips are compressed by springs.