The Franklin Institute Laboratories for Research and Development

• Publisher: Elsevier Science
• Year: 1950
• Tongue: English
• Weight: 507 KB
• Volume: 250
• Category: Article
• ISSN: 0016-0032
• DOI: 10.1016/0016-0032(50)90933-1

✦ Synopsis

Hydraulic applications have increased with improved flow controls. The most effective method of controlling the fluid is at the pump. The designs of both the radial and axial piston pumps lend themselves to variable-delivery by simply changing the pump displacement. Thus, the output can be altered without changing the speed of the motor. This method eliminates the power loss that is caused by either throttling or bypassing fluid. In addition, such a control device can change the direction of flow without requiring special valves or altering the direction of the driving motor. With these controls, the pump is well adapted for both heavy-duty service or for accurate drive control of such equipment as machine tools. The following sketches illustrate the method by which the pump displacement and pressure are regulated: