SU632523A1 - Device for pressing electrodes of resistance welding machines - Google Patents

Description

The invention relates to mechanical engineering, in particular, to the production of devices before compressing the electrodes of resistance welding machines.

A device is known that contains a number of bopey chambers and all of them transmit force through a common rod, and their switching points are arranged in time.

Devices are known in which the rate of change of force is controlled by varying the length of the time interval for the release of air from the backpressure chamber 21.

A common drawback of such devices is the discrete principle of operation, in which the main regulating element is a valve that has two states open or closed at each time interval.

A device containing a two-chamber force actuator is known, in which the compressive force on the electrodes of the chamber is connected via a first switching valve to a source of compressed air of a given working pressure, go to the atmosphere, and the anti-armpit chamber is connected to one channel through a flapper valve controlled by a second switching valve. , with a source of compressed air, go with the atmosphere, and a second channel through a non-return valve with a source of compressed BO3; ijxa ГзТ.

The disadvantage of this device is also the stepwise nature of the increase in the force on the electrodes, which affects the quality of welding.

The purpose of the invention is to improve the quality of welding by continuously setting and stabilizing the rate of increase of the force on the electrodes.

Claims (3)

The goal is achieved by the fact that the device is equipped with a throttle connected to the atmosphere and a regulator valve connected in series with it, connected to an external valve-swatter valve-insulated cavity, in which the petal of the non-return valve is solid. In addition, to stabilize the initial value of the force at the 36 start-up increase, the device is equipped with a third connected to the compressed air source and supplement the Shzny switching valve and, in series with it, an additional non-return valve connected to the outer band of the flapper valve and conducting the air towards it. . The drawing shows a diagram of devices. It contains a two-chamber pneumatic actuator 1, three electromagnetic switching controlled pneumatic valves 2.3 and 4, an inlet valve flapper 5, two check valves 6 and 7, a valve regulator 8 pressure, a throttle 9 with an adjustable clearance and a source of compressed air TO with adjustable outlet pressure. Flap valve 5 is connected to the lower chamber of the pneumatic actuator and valve 4 Pressure regulator valve 8 is attached to the outer cavity of the flapper valve 5, and in series with it, choke 9 with an adjustable clearance. Outlet throttle 9 is open to the atmosphere. It is possible to precisely regulate the gap in the bore hole of the throttles 9. A check valve b is connected to the same cavity of the valve-poppers 5, which conducts the air flow in the direction of the clapper board 5. A controlled switching solenoid valve 2 connected to the outlet is connected in series with it. valve 3, which includes compression of the electrodes; Another non-return valve 7 connects the lower chamber of the pneumatic actuator and the pneumatic network of a given working pressure. Conducts air flow check valve 7 in the direction from the lower chamber of the pneumatic actuator 1 to. The initial compressive force is created (as in a conventional welding machine) when valve 3 is turned on. The force on the actuator rod is equal to the difference of forces acting on the piston of the cylinder from the upper and lower chambers. A feature of the device operation at this stage is the flow of air of a given working pressure through the open passage of the electromagnetic valve 2, non-return valve 6, the external cavity of the valve-slam 5, the pressure regulator 8 and the throttle 9. The pressure regulator 8 the external cavity of the valve-: the edge is filled with compressed air under the same pressure as the lower chamber of the pneumatic actuator. , To create an increasing force g / key 4, three two valves at once, valve 4 and the newly introduced valve 2, the check valve 6 closes. Flap valve 5, which connects the lower chamber of the pneumatic actuator cylinder, is actuated. pressure regulating valve 8. The lower chamber of the cylinder is emptied. The pressure regulator 8 and the throttle 9 create a constant air flow rate, independent of the value of the specified working pressure in the lower chamber of the cylinder. Since at a given distance between the electrodes the volume of air in the lower chamber is constant, the rate of increase of force at a constant setting of the pressure regulator 8 depends on the size of the gap in the air pusher. When all valves are turned off, the circuit returns to its original state. The non-return valve 7 provides air bypass from the chamber of the cylinder back to the network of a given working pressure in the event of an additional stroke of the electrode, when the chamber volume first increases sharply and then decreases, as well as lowering the electrodes during a working stroke. The invention ensures linearity up to a level of 0.9 of the maximum value with an accuracy of no worse than 5%. Formula izob, reteni 1, Device for compressing electrodes of contact welding machines, containing a two-chamber drive force, in which the compressive force on the electrodes chamber is connected through a first switching valve to a source of compressed air of a given working pressure or atmosphere, and the backpressure chamber is connected by one channel through the flapper valve, controlled from the second switching valve, with a source of compressed air / spirit or with the atmosphere, and the second channel through a check valve with a source of compressed air a, that is, so that, in order to improve the quality of welding by continuously setting and stabilizing the rate of increase of force on the electrodes, the device is equipped with a throttle connected to the atmosphere and connected in series with the regulating valve connected to the outer valve-populated cavity, at 563 of which the test-tube of the reverse valve is snapped out solid. 2. A device according to claim 1, in which, with a chain of improvement in the quality of welding, by stabilizing the initial value of the magnitude of the force when the increase is switched on; it is equipped with a third additional switching valve connected to the compressed air source and connected with it by an additional check valve connected to the external cavity of the flapper valve and conducting the air towards it. Sources of information taken into account in the examination: 1. Zaichik L.V. and others. Contact welding of light alloys, Mashgiz, 1963, p. 58, BUT. 2. The copyright certificate number 477802, B 23 to 11/10, 1973. 3. L. Glebov et al. Installation and operation of resistance welding machines, Energie, L., 1973.