Filtration apparatus for a hydraulic system

• US 6,063,269 A
• Filed: 08/06/1998
• Issued: 05/16/2000
• Est. Priority Date: 08/06/1998
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Miller, Christopher O., Ramamoorthy, Chandrasekar
• Primary Examiner(s): Savage, Matthew O.
• Application Number:
  US09/130,326
• Time in Patent Office: 649 Days
• Field of Search: 210/168, 210/171, 210/194, 210/196, 210/416.1, 210/416.5, 210/167, 210/172, 210/428, 60/453, 60/454, 417/76
• US Class Current: 210/167.01
• CPC Class Codes: B01D 2201/208 by venturi systems
• CPC Class Codes: B01D 29/90 for feeding

Abstract

Apparatus for improving the efficiency of filtering fluid of a hydraulic system, including a venturi adapted for connection to a first fluid carrying conduit of the hydraulic system for receiving a flow of the fluid therefrom, the venturi having a restricted passage extending therethrough and an orifice communicating therewith, a diverter conduit connected in communication with the orifice and with a second fluid carrying conduit of the hydraulic system, the diverter conduit containing a restricted orifice therein, and the venturi having an outlet connected in fluid communication with a filter, wherein the flow of the fluid through the restricted passage of the venturi will generate a reduced pressure condition in the diverter conduit to divert at least some of the fluid in the second fluid carrying conduit of the hydraulic system into the diverter conduit so as to pass into the venturi and flow onto the filter, the reduced pressure condition being weak or strong in correspondence to the fluid flow through the venturi so as to regulate the diverted flow.

Claims

1. A hydraulic system having an apparatus for filtering fluid therein, the hydraulic system comprising:

a reservoir;

first and second fluid carrying conduit connected to the reservoir;

a venturi having an inlet connected to the first fluid carrying conduit of the hydraulic system for receiving a flow of the fluid therefrom, an outlet, and a continuous sidewall extending between the inlet and outlet forming a passage for the flow of the fluid through the venturi, the passage having a restricted portion located intermediate the inlet and the outlet, and the sidewall having an orifice therein communicating with the passage in the vicinity of the restricted portion thereof;

a filter having an inlet, an outlet, and a passage for the flow of the fluid extending therebetween containing a filtration medium, the inlet of the filter being connected in communication with the outlet of the venturi for receiving the flow of the fluid therefrom, and the outlet of the filter being connected to the reservoir through a return conduit for passage of the flow of the fluid thereto; and

a diverter conduit having a first end connected to the orifice in the sidewall of the venturi in communication with the restricted portion therein and a second end connected to the second fluid carrying conduit of the hydraulic system, the diverter conduit containing a restricted orifice therein, wherein the flow of the fluid through the restricted orifice portion of the passage of the venturi will generate a reduced pressure condition in the orifice in the sidewall of the venturi and in the diverter conduit operable to divert at least some of the fluid in the second fluid carrying conduit into the diverter conduit so as to pass therethrough and through the restricted orifice thereof into the passage of the venturi so as to flow through the filter and return to the hydraulic system, the restricted orifice operating to meter the flow of the fluid through the diverter conduit.

2. The hydraulic system, as set forth in claim 1, wherein the first fluid carrying conduit is connected in communication with a case of the hydraulic system.

3. The hydraulic system, as set forth in claim 1, wherein the return conduit of the hydraulic system is connected in communication with a pilot pump for passage of the flow of the fluid thereto.

4. The hydraulic system, as set forth in claim 1, wherein the second fluid carrying conduit of the hydraulic system comprises a main return conduit of the hydraulic system.