DD267689A1

DD267689A1 - DEVICE FOR PRESSURE MONITORING OF PRESSURE-RELATED SPANNING CYLINDERS

Info

Publication number: DD267689A1
Application number: DD30991887A
Authority: DD
Inventors: Juergen Kuehner
Original assignee: Spezialwerkzeugfabrik Zella Me
Priority date: 1987-12-04
Filing date: 1987-12-04
Publication date: 1989-05-10

Abstract

Die Erfindung betrifft eine Einrichtung zur Druckueberwachung an druckmittelbetaetigten Spannzylindern, insbesondere an Drehmaschinen, bei der vor dem Spannzylinder im Sinne des Druckmitteldurchlaufes ein Druckschalter und eine Leitungswechseleinrichtung angeordnet ist. Die Aufgabenstellung der Erfindung besteht darin, zur sicherheitstechnischen Vervollkommnung des Spannsystems an druckmittelbetaetigten Spannzylindern eine Einrichtung zu schaffen, mit der die Druckueberwachung des Spannzustandes unabhaengig von der Spannrichtung des Spannzylinders gewaehrleistet ist. Die Loesung dieser Aufgabe besteht darin, dass der der Druckueberwachung dienende Druckschalter unmittelbar am Stellglied der Leitungswechseleinrichtung angeordnet ist und stetig an der den Spannzustand bewirkenden Druckmittelzuleitung anliegt. FigurThe invention relates to a device for pressure monitoring of pressure-medium-operated clamping cylinders, in particular on lathes, in which a pressure switch and a line change device is arranged in front of the clamping cylinder in the sense of Druckmitteldurchlaufes. The object of the invention is to provide a device for safety-related perfection of the clamping system on druckmittelbetaetigten clamping cylinders, with which the Druckueberwachung the clamping state is guaranteed independently of the clamping direction of the clamping cylinder. The solution of this problem is that the pressure monitoring serving pressure switch is located directly on the actuator of the line changing device and steadily applied to the clamping state causing pressure medium supply line. figure

Description

Hierzu 1 Seite ZeichnungFor this 1 page drawing

Field of application of the invention

Die Erfindung betrifft eine Einrichtung zur Drucküberwachung an druckmittelbetätigten Spannzylindern, Insbesondere an Drehmaschinen, bei der vor dem Spannzylinder im Sinne des Druckmitteldurchlaufes ein Druckschalter und eine Leitungswechseleinrichtung angeordnet ist.The invention relates to a device for monitoring the pressure on pressure-operated clamping cylinders, in particular on lathes, in which a pressure switch and a line change device is arranged in front of the clamping cylinder in the sense of Druckmitteldurchlaufes.

Characteristic of the known state of the art When equipped with power chucks machine tools, it is '' en pressure in the lines welcho the pressure medium

zum Spannzylinder führen, zu überwachen, um bei Druckabfall die Werkzeugmaschine sofort selbsttätig stillzusetzen.lead to the clamping cylinder, monitor, to shut down the machine tool automatically in case of pressure drop.

This measure is intended to prevent the occurrence of accidents. The pressure switches used for monitoring the working pressure of fluid-operated clamping cylinders are hereby

auf einen Mindestdruck eingestellt und können mit ihren Einstellmitteln an den jeweils erforderlichen Spanndruck angepaßt werden.set to a minimum pressure and can be adjusted with their adjustment to the required clamping pressure.

In known devices of this type, the pressure switch in front of the directional control valve for reversing the clamping cylinder on the Clamping and Lösezus'and arranged. In this way, the respective inlet pressure is monitored before the reversing valve. The disadvantage of this is that the actual clamping pressure acting in the clamping cylinder is not monitored and in Direction after the reversing valve occurring pressure drop can not be detected by the pressure switch. Furthermore, it is known in principle to provide a line change device within the clamping devices, so at Clamping direction change from external to internal clamping the actuators always in the same clamping state

entsprechen.correspond.

According to DD-PS 48903, such a line change device consists of the stationary air supply housing and

einer mit Steuerschlitzen versehenen verstellbaren Steuerscheibe.a provided with control slots adjustable control disc.

The pressure monitoring takes place with the aforementioned components locally before the reversing valve, which leads to the fact that in the Clamping cylinder inside acting clamping pressure is not actually monitored. By DE-OS 3004 293 and DE-OS 3008333 has already been proposed in the circumferential part of the clamping cylinder a

jedem Spannzylinder zugeordneten federbelasteten Hilfskolben vorzusehen. Dieser Hilfskolben kommuniziert einerseits mit den beiden Zylinderräumen und betätigt andererseits einen Signalstift, der seinerseits einen verschiebbaren Grenztaster betätigt.provide each spring-loaded auxiliary piston associated with each clamping cylinder. This auxiliary piston communicates on the one hand with the two cylinder chambers and on the other hand actuates a signal pin, which in turn actuates a displaceable limit switch.

These solutions require a part of a relatively high construction cost and have the other part the disadvantage that the Elements for setting the clamping pressure are difficult to access and can only be set inaccurate. In addition, the clamping and release position for the tendons on the grips is not recognizable. According to DE-OS 30 23413 a device for monitoring the clamping pressure is known in which the pressure monitoring after

der Leitungswechseleinrichtung angeordnet ist. Diese Einrichtung sieht für jede Leitung einen gesonderten Druckschalter vor.the line change device is arranged. This device provides a separate pressure switch for each line.

This has the disadvantage that when the clamping direction change and the pressure switch are swapped or changed accordingly

müssen.have to.

This change requires careful handling of the adjusting members, because if this change is avoided

den Druckschaltern Fehlinformationen entstehen und dadurch bedingte Gefährdungen nicht erkannt werden.Faulty information is generated by the pressure switches and thus the associated hazards are not recognized.

Object of the invention

Das Ziel der Erfindung besteht darh, das Spannsystem an druckmittelbetätigten Spannzylindern mit technisch einfachen Mitteln in funktionell und sicherheitr.te'.hnischer H^:nsicht zu vervollkommnen.The object of the invention darh, the clamping system of fluid-actuated clamping cylinders with technically simple means in functional and sicherheitr.te'.hnischer ^H: to perfect iew.

Explanation of the essence of the invention The invention has for its object to provide a device with which the pressure monitoring of the clamping state

unabhängig von der Spannrichtung des Spannzylinders gewährleistet ist.is guaranteed regardless of the clamping direction of the clamping cylinder.

Diose object is achieved according to the invention in that the pressure switch directly on the actuator of Line change device is arranged and steadily applied to the clamping state causing pressure medium line. In a further embodiment of the solution according to the invention, the pressure switch is in the region of the clamping cylinder

umlaufenden Teiles der Luftzuführung und quer zum Stellglied der Leitungswechseleinrichtung angeordnet.circumferential part of the air supply and arranged transversely to the actuator of the line changing device.

The immediate arrangement of the pressure switch on the actuator has the advantage that compared to the construction

solcher Einrichtungen nach dem bekannten Stand der Technik der Druckschalter, ohne daß Verwechslungen auftreten können, stets die den jeweiligen Spannzustand bewirkende Druckmittelzuleitung überwacht, unabhängig davon, welche Spannrichtung dem Spannzylinder jeweils aufgegeben ist.Such devices according to the prior art, the pressure switch, without confusion may occur, always monitors the respective clamping state causing pressure medium supply line, regardless of which clamping direction the clamping cylinder is abandoned in each case.

This is done in a simple manner in that the pressure switch when setting the clamping direction of the actuator Line change device is brought into the switching position, which corresponds to the state. Span ". By this measure, as is known in the devices according to the prior art, the installation of a

zweiten Druckschaltes verzichtet werden.second pressure switch be waived.

Finally, another advantage of the solution according to the invention is that with appropriate coupling with the Machine control a start of the machine is blocked until the required clamping pressure in the clamping device

tatsächlich anliegt.actually applied.

In the known arrangements of pressure monitoring elements, in which so the pressure switch before the Line change device is attached, although the applied input pressure is displayed by the pressure generator ago, however

nicht der im Inneren des Spannsystems vorhandene Arbeitsdruck kontrolliert, wie das für die Erhöhung der Arbeitssicherheit an solchen Spannsystemen geboten ist.does not control the existing in the interior of the clamping system working pressure, as required for increasing the safety at such clamping systems.

embodiment The solution according to the invention will be briefly explained below on an exemplary embodiment. In the accompanying drawing an embodiment of the invention is diagrammatically ddrgestellt. The drawing represents one

teilweise Seitenansicht des druckmittolbetätigten Spannzylinders mit angebauter Luftzuführung undpartial side view of the pressure-medium-actuated clamping cylinder with mounted air supply and

Line change direction with the pressure switch put into position. The device according to the invention consists essentially of the clamping cylinder 1 with clamping piston 2 in a known Flanged way, with the clamping cylinder 1 rotating part 3 of the air supply 8, from the stationary part 4 of Air supply 8 and arranged from the stationary part 4 of the air supply 8 pivotally, the

l.eitungswechseleinrichtung darstellenden Stellglied 5. Am Stellglied 5 ist der Druckschalter 6 angebracht derart, daß dieOn the actuator 5, the pressure switch 6 is mounted such that the

Input side of the pressure switch 6 at the clamping state causing Druckmittolzuleitung 7 is applied. When pivoting the actuator 5 for the purpose of a clamping direction change the pressure switch 6 is inevitably in

entsprechenden Sinne mitbewegt, so daß er stets an der den Spannzustand bewirkenden Druckmittelzuleitunf inliegt und den dort vorhandenen Spanndruck überwacht, unabhängig davon, welche Spannrichtung dem Spannzylinder jeweils aufgegebenmoved according to the meaning, so that it always rests on the clamping state causing Druckmittelzuleitunf and monitored there existing clamping pressure, regardless of which clamping direction the clamping cylinder respectively abandoned

Due to the nature of its spatial arrangement to the actuator 5 and the stationary part 4 of the air supply is the Pressure switch 6 saves space and also protected against mechanical damage.

Claims

1. A device for Druckübeiwachung on pressure-operated clamping cylinders, in particular on lathes, in which a pressure switch and a line change device is arranged in front of the clamping cylinder in the sense of Druckmitteldurchlauf, characterized in that the pressure switch (6) is arranged directly on the actuator (5) of the line change infeed and steadily applied to the clamping state causing pressure medium supply line (7).

2. Pressure monitoring device according to claim 1, characterized in that the pressure switch (6) in the region of the clamping cylinder (1) rotating part (3) of the air supply (3; 4) and transversely to the actuator (5) of the line change device is arranged ,