Viscous material pump

• US 5,336,052 A
• Filed: 04/28/1993
• Issued: 08/09/1994
• Est. Priority Date: 04/28/1993
• Status: Expired due to Fees

• Current Assignee: Abel Pumpen GmbH & Co. KG
• Original Assignee: Abel Pumpen GmbH & Co. KG
• Inventors: Zollner, Jorg-Peter, Bussmann, Winfried
• Primary Examiner(s): Gluck, Richard E.
• Application Number:
  US08/054,409
• Time in Patent Office: 468 Days
• Field of Search: 417/900, 417/20, 417/44 R, 417/44 A, 417/205
• US Class Current: 417/20
• CPC Class Codes: F04B 15/02 the fluids being viscous or non-homogeneous
• CPC Class Codes: F04B 2201/0201 Position of the piston
• CPC Class Codes: F04B 2205/05 Pressure after the pump outlet
• CPC Class Codes: F04B 49/065 and making use of computers
• CPC Class Codes: Y10S 417/90 Slurry pumps, e.g. concrete

Abstract

The present invention relates to a viscous material pump. According to the invention, a pressure sensor is associated with the hydraulic drive cylinder of the fixed displacement pump for generating a pressure signal when a first sudden pressure increase occurs after the drive piston moves out of its end position. The volume subsequently displaced by the conveying piston corresponds to the actual delivery volume during the pumping stroke. A processor calculates the actual delivery volume for each pumping stroke using the ratio between the stroke time, as defined by the occurrence of the pressure peak and the maximum available conveying volume of the cylinder, as defined by the stroke time the piston needs to move from its first to its second end position. The present invention further provides for adjusting the supply volume of a supply means discharging the material to the viscous material pump. To this purpose the pumping stroke time of the conveying cylinder up to the pressure increase in the drive cylinder is compared with a predetermined time for generating a signal to increase the supply volume when the measured stroke time exceeds a predetermined time.

Claims

1. A pump for pumping viscous material including in combination:

at least a pump cylinder having a supply line and a delivery line and having a pump piston connected to a drive piston of a hydraulic drive cylinder in order to be operated between a suction stroke for filling the viscous material into said pump cylinder and a pumping stroke for conveying the viscous material out of said pump cylinder;

end position transmitters structured and arranged to said hydraulic drive cylinder for generating a signal indicating the end position of said drive piston;

valve means communicating with said delivery outlet of said pump cylinder and controlled by the signals of said end position transmitters, which valve means operates to connect said pump cylinder to said supply line during said suction stroke and to said delivery line during said pumping stroke, respectively;

pressure switch means connected to said hydraulic drive cylinder for generating a pressure signal in case pressure increase occurs when said pump piston has left its end position at the beginning of said pumping stroke;

a time measuring means for determining the time duration of the travel of said pump piston between said end position at the beginning of said pumping stroke and said occurrence of said pressure signal;

drive means,

supply means driven by said drive means for conveying the viscous material to be pumped into said supply line for delivery to said pump cylinder, with at least one of said drive means and said supply means being controllable to change the flow volume of the viscous material supplied to said pump cylinder; and

comparator means for comparing said time duration of said pumping stroke until said occurrence of said pressure increase with a predetermined time interval and for generating a signal when said measured time duration exceeds a predetermined time interval, with aid signal being transmitted to at least one of said drive means and said supply means for increasing the flow volume of the viscous material to said pump cylinder.

2. The viscous material pump of claim 1 wherein said drive means is a hydraulic motor.

3. The viscous material pump of claim 1 wherein said drive means is an electro motor.

4. The viscous material pump of claim 2 wherein when a pressure sensor means measures the pressure of said drive cylinder to generate a pressure signal which exceeds a predetermined pressure value, said signal is transmitted to said supply means for decreasing the flow volume of the viscous material to said pump cylinder.

5. The viscous material pump of claim 3 further including measuring means for measuring the current of said electro motor to generate a current signal which exceeds a predetermined current value, with said signal being transmitted to said supply means for decreasing the flow volume of the viscous material to said pump cylinder.