Method of controlling a pump apparatus for conveying viscous material, and control system for such a pump apparatus

Abstract

In a method of controlling a pump apparatus for conveying viscous material from at least two main delivery cylinders to a delivery pipeline, a sequence control is provided which runs a sequence program for executing operation of at least two control elements of the pump apparatus in a fixed timing sequence.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS [0001] This application claims the priority of German Patent Application, Serial No. 10 2005 024 174.3-15, filed May 23, 2005, pursuant to 35 U.S.C. 119(a)-(d), the subject matter of which is / are incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] The present invention relates to a method of controlling a pump apparatus for conveying viscous material, and to a control system for such a pump apparatus. [0003] Nothing in the following discussion of the state of the art is to be construed as an admission of prior art. [0004] Pumps of a type involved here are used in the field of concrete conveyance and include at least two main delivery cylinders which convey viscous material to a delivery pipeline. In order to realize a substantially continuous material flow, the main delivery cylinders are operated substantially in opposite mode so that at any given time one of the main delivery cylinders is able to conduct concrete to the del...

AI Technical Summary

Benefits of technology

[0016] As actuation of the control elements can now depend on the execution of a sequence program and, except for the start signal, can be made independent on a state determination of the system, a reliable control system can be realized which is able to properly position all hydraulic valves of a concrete pump, for example during startup of the concrete pump, so that all drives for an optional gate mechanism, including the shut-off gates and the drives for the pistons of the main delivery cylinders can be moved in appropriate direction or maintained in their position so long as conforming to the executed operations. Moreover, the following pump operation can be carried out reliably, even when the delivery flow changes at short notice and even after standstill.

[0025] According to another feature of the present invention, the rotation of a camshaft with cams for switching the control elements of the pump apparatus may be triggered by a start signal. The use of a camshaft with cams for switching at least two control elements of the pump apparatus provides for a fixed association between the actuation of the control elements relative to one another because the cams of the camshaft are positioned at a fixed relationship to one another while allowing at the same time to freely select the clock frequency so that the timing sequence of the sequence program can be accelerated or retarded, without changing the sequence in actuation of the control elements in relation to the clock pulse.

[0035] According to another aspect of the present invention, a control system for a pump apparatus for conveying viscous material includes a camshaft having at least one cam for actuating a contact member for operating a control element of a pump apparatus having at least two main delivery cylinders for conveying viscous material. The use of a camshaft for switching the control elements of the pump apparatus permits execution of a sequence program by which a fixed timing sequence is established for actuating the control elements of the pump apparatus. As a result, the control elements can be actuated in fixed relationship to one another after starting the sequence program.

Problems solved by technology

Conventional controls cannot reliably realize such operations heretofore.

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