DE1051710B - Device for keeping the pressing pressure of screw-strand or similar presses for clay and similar masses constant - Google Patents

Description

For measuring the pressing pressure in screw extrusion or similar presses, in which masses of clay Or similar plastic material are processed, measuring devices are known in which about a Pressure gauge with minimum and maximum contact device if the desired value is exceeded or not reached Pressing pressure at the irrigation point in the preparation course of the clay, z. B. on pan mill, red and green signal lamps are made to light up. The worker responsible for irrigation can then open the water valve more or less and so manually back to the desired and on Adjust the pressure set on the pressure gauge, which depends on the water content. It's a facility too known to keep the pressure of presses constant, in which a under the action of Compression pressure standing piston over switch, which is exceeded or fallen below a predetermined Pressing pressure become effective, with a directly regulating the water supply to the irrigation point hydraulic or pneumatic device is connected. With this known device can however, only a set minimum and maximum can be delimited by means of switching contacts. For everyone in between Measuring points must be activated by auxiliary staff such as compressed air will.

The known \ ^A orrichtung is just like the known controls that regulate the addition of water to extrusion presses via electrical measurements and corresponding electrical switching devices, too expensive and complicated in structure and therefore too sensitive to interference for robust operation, especially because of the use of volumetric flasks.

The invention is intended to provide a simple, interference-insensitive and fully automatic device for constant regulation of the compression pressure on screw extrusion presses or the like. Created be, in which the pressing pressure as a control variable in a known manner from a pressure measuring device to a influencing the water supply to the irrigation point in the treatment aisle, for example in the pan mill Facility is given.

According to the invention, a membrane under the action of the pressing pressure is via a hydraulisdhe Line with the pressure gauge via a second hydraulic line with a water supply Direct hydraulic valve connected to the irrigation barn in the treatment area, wherein the pressure acting on the membrane is hydraulically applied to a further membrane in the Control valve is transferred, which with two regulating the water flow, under adjustable back pressure standing piston with a device between them

to keep the pressing pressure constant

of screw extrusion or similar presses

for clay and similar masses

Applicant:

Karl Handle & Sons

Machine factory and iron foundry,

Mühlacker (Württ), Lienzinger Str. 95

Dipl.-Ing. Dr. Georg Handle and Erwin Räkers,

Mühlacker (Württ.),
have been named as inventors

Leave the annular gap free for the water penetration, in active connection.

In a particularly expedient embodiment of the invention is that acting on the piston Counterforce designed as an adjustable spring, which is separated from the piston chamber by a membrane is.

In the control device according to the invention, the actuating force of the valve is pressure due to the pressing itself generated, the spring and the annular gap between the valve piston are designed so that the the amount of water flowing to the irrigation point is proportional to the pressure in the press. This control device according to the invention will generally suffice where the distance between The measuring point and control point are not too large or where the moisture balance is not so large Change shows.

Is the control point at which the water is to be added to the clay at a more distant one? If there are significant differences in humidity or if there are significant differences in humidity, an additional device must be used or other devices appropriate. In this case, the invention provides for the connection of a Solenoid valve in addition to the basic control according to the invention to compensate for peaks that arise before, with at least one influencing the water supply via switching contacts in the pressure gauge for peak compensation Solenoid valve is provided.

An embodiment of the device according to the invention is shown in the drawing.

809 767/333

Claims (3)

The pressing pressure acts on the membrane 2 of a known pressure measuring device, which is arranged at a suitable point in the press, so that this pressure on the one hand on the hydraulic filling of the line 3 of the pressure measuring device with manometer 5 and on the other hand S on the line 4 to which the water flow to the irrigation point 18 regulates Valve 8 is transmitted. In the control valve 8, the pressure reaches a membrane 7 closing off the pressure oil chamber 6, against which a plate 8 &, which is connected to piston 8α ο and 8a ', rests. The bulging of the membrane 7 caused by an increase in pressure in the line 4 is transferred to the pistons 8 a and 8 a 'and tries to move them upwards. Since the opposite end of the pistons is under the force of an adjustable spring 14, they can only move upwards when the set spring pressure is exceeded. To adjust the spring pressure, a hand wheel 17 is provided on a spindle 13, by means of which a spring plate 15 can be adjusted. An adjustment scale 22 enables the spring 14 to be set precisely. In the exemplary embodiment, the pistons 8 a and 8 a 'are symmetrical to the axis of the inlet and outlet bores 10 a and 11 a provided in part 9 and located in one plane. A counter plate 8b 'adjoining the piston rests against an upper membrane 12 which closes part 9 against the part of the control valve that receives the spring. With 10 the inflow line and with 11 the line leading to the irrigation point 18 is designated. A free ring gap for the passage of water is provided between the pistons 8 a, 8 a '. If, in addition to this direct basic control at peak pressures, it is necessary to switch on a further irrigation point 23 to the pan 1, a solenoid valve (20), which is arranged in a further water supply line 21, is advantageously switched on via pressure switch contacts known per se. Patent claims: 1. A device for keeping the pressing pressure of screw extrusion or the like presses for clay and similar masses constant, in which the pressing pressure is given as a control variable from a pressure measuring device to a water supply device arranged in the processing passage of the material to be pressed, characterized in that one under the action of the pressing pressure standing membrane (2) is connected via a hydraulic line (3) to the manometer (5) and via a second hydraulic line (4) to a hydraulic valve (8) which directly regulates the water supply to the irrigation point (18) in the treatment, wherein the pressure acting on the membrane (2) is transferred hydraulically to a further membrane (7) in the control valve (8), which with two pistons (8 a, 8 a ') which regulate the water flow and are under adjustable counter pressure, which have a Leave the annular gap free for the passage of water, is in operative connection. 2. Apparatus according to claim 1, characterized in that the counterforce acting on the pistons (8 a, 8 α ') is designed as an adjustable spring (14) which is separated by a membrane (12) from the space of the piston (8 a, 8 a ') is separated. 3. Apparatus according to claim 1 or 2, characterized in that at least one further water supply influencing solenoid valve (20) is provided for peak compensation via switching contacts in the pressure gauge (5). Considered publications:
U.S. Patent No. 1,879,367. 1 sheet of drawings ® 809 767/333 2. Si