# US 6,293,849 B1 · Polishing solution supply system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,293,849 B1 - Document ID: US6293849B1 - Status: Granted - Kind: B1 - Application number: 09/181,993 - Filed: 1998-10-29 - Granted: 2001-09-25 - Earliest claimed: 1997-10-31 - Assignees: Ebara Corporation - Inventors: Kiyotaka Kawashima - Web page: https://patentgrep.com/patent/US6293849B1 ## CPC - B24B 37/04: designed for working plane surfaces - B24B 57/02: for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents - H10P 52/00: Grinding, lapping or polishing of wafers, substrates or parts of devices - B24B: MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING (grinding of gear teeth B23F, of screw-threads B23G1/36; by electro-erosion B23H; abrasive or related blasting B24C; tools for grinding, buffing or sharpening B24D; polishing compositions C09G1/00; abrasives C09K3/14; electrolytic etching or polishing C25F3/00; grinding arrangements for use on assembled railway tracks E01B31/17); DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract A polishing solution supply system can prevent precipitation of solutes on delivery pipes or interior walls of holding tanks so that a polishing solution of a constant solution concentration can be supplied to a polishing tool. The polishing solution supply system includes a stock solution supply source, a dilution solution supply source, and a mixing section for mixing a stock solution and a dilution solution to formulate the polishing solution. The mixing section is sealed hermetically to exclude external atmosphere. Delivery lines deliver the polishing solution to each of plural polishing sections. ## Claims ### Claim 1 A polishing system comprising: a polishing section for pressing an object to be polished against a polishing tool; a delivery line to communicate with an external polishing solution supply source for delivering a polishing solution to said polishing section; a flow control device for controlling flow of the polishing solution within said delivery line at a desired flow rate within a range of flow rates in response to a command signal; and a shutoff valve for stopping the flow of the polishing solution within said delivery line, wherein said delivery line comprises a circulation line in which the polishing solution can always flow, and a delivery pipe extending directly from said circulation line toward said polishing section. ### Claim 2 (depends on 1) A system as claimed in claim 1, further comprising a trunk line to communicate with the external polishing solution supply source, wherein said circulation line constitutes a portion of said trunk line. ### Claim 3 A polishing system comprising: a polishing section for pressing an object to be polished against a polishing tool; a delivery line to communicate with an external polishing solution supply source for delivering a polishing solution to said polishing section; a flow control device for controlling flow of the polishing solution within said delivery line at a desired flow rate in response to a command signal; and a shutoff valve for stopping the flow of the polishing solution within said delivery line, wherein said flow control device includes a pressure adjustment valve for adjusting a pressure at a downstream side of said flow control device to a specific value determined by said command signal. ### Claim 4 (depends on 3) A system as claimed in claim 3, wherein said flow control device further includes a constriction device provided at a downstream side of said pressure adjustment valve. ### Claim 5 (depends on 1) A system as claimed in claim 1, further comprising a cleaning liquid delivery pipe for delivering a cleaning solution to said flow control device. ### Claim 6 (depends on 1) A system as claimed in claim 1, further comprising a housing enclosing said polishing section and said delivery line. ### Claim 7 A polishing system comprising: a polishing section for pressing an object to be polished against a polishing tool; an external polishing solution supply source; a delivery line communicating with said external polishing solution supply source for delivering a polishing solution to said polishing section; a flow control device for controlling flow of the polishing solution within said delivery line at a desired flow rate within a range of flow rates in response to a command signal; and a shutoff valve for stopping the flow of the polishing solution within said delivery line, wherein said delivery line comprises an extended circulation line in which the polishing solution can always flow and a delivery pipe extending directly from said extended circulation line toward said polishing section. ### Claim 8 (depends on 7) A system as claimed in claim 7, further comprising a trunk line to communicate with said external polishing solution supply source, wherein said extended circulation line constitutes a portion of said trunk line. ### Claim 9 (depends on 7) A system as claimed in claim 7, a polishing system comprising: a polishing section for pressing an object to be polished against a polishing tool; an external polishing solution supply source; a delivery line to communicate with said external polishing solution supply source for delivering a polishing solution to said polishing section; a flow control device for controlling flow of the polishing solution within said delivery line at a desired flow rate in response to a command signal; and a shutoff valve for stopping the flow of the polishing solution within said delivery line, wherein said flow control device includes a pressure adjustment valve for adjusting a pressure at a downstream side of said flow control device to a specific value determined by said command signal. ### Claim 10 (depends on 9) A system as claimed in claim 9, wherein said flow control device further includes a constriction device provided at a downstream side of said pressure adjustment valve. ### Claim 11 (depends on 7) A system as claimed in claim 7, further comprising a cleaning liquid delivery pipe for delivering a cleaning solution to said flow control device. ### Claim 12 (depends on 7) A system as claimed in claim 7, further comprising a housing enclosing said polishing section and said delivery line. ### Claim 13 A polishing system comprising: a polishing solution supply system for preparing a polishing solution; a plurality of polishing sections for polishing an object; by pressing said object against a polishing tool, wherein each of said polishing sections includes a delivery line for communicating with said polishing solution supply system and delivering polishing solution to said respective polishing section; and a circulation pipe communicating with said polishing solution supply system and said delivery lines of said polishing sections, wherein said circulation pipe is adapted to circulate only unused polishing solution therein. ### Claim 14 (depends on 13) A polishing system as claimed in claim 13, wherein each of said delivery lines includes a flow control device for controlling the flow of the polishing solution. ### Claim 15 (depends on 13) A polishing system as claimed in claim 13, wherein each of said delivery lines includes a pressure adjustment device for adjusting a pressure of the polishing solution in said respective polishing section. ### Claim 16 (depends on 13) A polishing system as claimed in claim 13, wherein said polishing solution supply system comprises a mechanism for controlling a concentration of the polishing solution. ### Claim 17 (depends on 13) A polishing system as claimed in claim 13, wherein said polishing solution supply system is operable to mix a stock solution and a dilution solution. ### Claim 18 (depends on 13) A polishing system as claimed in claim 13, wherein each of said delivery lines is connectable to a cleaning fluid pipe. ### Claim 19 (depends on 13) A polishing system as claimed in claim 13, wherein said circulation pipe has connecting portions that are connectable to said delivery lines for supplying the polishing solution to one of said polishing sections. ### Claim 20 (depends on 13) A polishing system as claimed in claim 13, wherein said recirculating pipe includes a plurality of branch lines connected to said delivery lines, respectively, and a plurality of shutoff valves disposed in said branch lines, respectively.