# US 11,077,671 B2 · Liquid discharge device, image forming apparatus, and fabricating apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,077,671 B2 - Document ID: US11077671B2 - Status: Granted - Kind: B2 - Application number: 16/677,490 - Filed: 2019-11-07 - Published: 2020-05-14 - Granted: 2021-08-03 - Earliest claimed: 2018-11-14 - Assignees: Ricoh Company, Ltd. - Applicants: Ryohki Wakasa; Atsushi Mori; Yuuichiroh Uematsu - Inventors: Ryohki Wakasa; Atsushi Mori; Yuuichiroh Uematsu - Web page: https://patentgrep.com/patent/US11077671B2 ## CPC - B41J 2/18: Ink recirculation systems - B41J 2/14201: {Structure of print heads with piezoelectric elements} - B41J 2/175: Ink supply systems {; Circuit parts therefor} - B41J 29/38: Drives, motors, controls or automatic cut-off devices for the entire printing mechanism - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## Abstract A liquid discharge device includes a storage tank, a discharge head, a liquid feeder, a supply tank, a liquid path, a branch path, and a flow regulator. The liquid feeder is configured to feed liquid from the storage tank to the discharge head in a liquid feed direction. The supply tank is disposed upstream of the discharge head in the liquid feed direction, to store the liquid fed by the liquid feeder while being in a state open to atmosphere. The liquid path is configured to flow the liquid from the liquid feeder to the supply tank. The branch path is connected to the liquid path and configured to cause part of the liquid to branch from the liquid path. The flow regulator is disposed downstream of the discharge head in the liquid feed direction and configured to control a flow rate of the liquid flowing into the discharge head. ## Claims ### Claim 1 A liquid discharge device comprising: a storage tank configured to store a liquid; a discharge head configured to discharge the liquid; a liquid feeder configured to feed the liquid from the storage tank to the discharge head in a liquid feed direction; a supply tank disposed upstream of the discharge head in the liquid feed direction and configured to store the liquid fed by the liquid feeder while being in a state open to atmosphere; a liquid path configured to flow the liquid from the liquid feeder to the supply tank; a flow regulator disposed downstream of the discharge head in the liquid feed direction and configured to control a flow rate of the liquid flowing into the discharge head; and a branch path connected to the liquid path that is configured to cause part of the liquid to branch from the liquid path, wherein the branch path connects an upstream side of the supply tank in the liquid feed direction to a downstream side of the flow regulator in the liquid feed direction to mitigate pressure fluctuations of the liquid at the discharge head as the flow regulator controls the flow rate of the liquid flowing into the discharge head. ### Claim 2 (depends on 1) The liquid discharge device according to claim 1, wherein the discharge head is disposed at a position higher than the supply tank. ### Claim 3 (depends on 1) The liquid discharge device according to claim 1, wherein the branch path at the downstream side of the flow regulator is connected to another liquid path disposed downstream of the flow regulator in the liquid feed direction. ### Claim 4 (depends on 1) The liquid discharge device according to claim 1, wherein the branch path at the downstream side of the flow regulator is connected to the storage tank. ### Claim 5 (depends on 1) The liquid discharge device according to claim 1, wherein the flow regulator controls the flow rate of the liquid flowing into the discharge head to be constant without receiving an instruction from an external device. ### Claim 6 (depends on 1) The liquid discharge device according to claim 1, wherein the flow regulator includes a flow control valve, and wherein the flow regulator detects the flow rate of the liquid flowing into the discharge head and controls opening of the flow control valve on basis of the flow rate detected. ### Claim 7 (depends on 1) The liquid discharge device according to claim 1, wherein the supply tank is formed of a flexible member. ### Claim 8 (depends on 1) The liquid discharge device according to claim 1, wherein the liquid path comprises a tube connecting the storage tank to the supply tank. ### Claim 9 (depends on 1) An image forming apparatus comprising the liquid discharge device according to claim 1. ### Claim 10 (depends on 1) A fabricating apparatus comprising the liquid discharge device according to claim 1. ### Claim 11 A liquid discharge device comprising: a storage tank configured to store a liquid; a discharge head configured to discharge the liquid; a liquid feeder configured to feed the liquid from the storage tank to the discharge head in a liquid feed direction; a recovery tank; a detector configured to detect an amount of the liquid in the recovery tank; a supply tank disposed upstream of the discharge head in the liquid feed direction and configured to store the liquid fed by the liquid feeder while being in a state open to atmosphere; a liquid path configured to flow the liquid from the liquid feeder to the supply tank; a flow regulator disposed downstream of the discharge head in the liquid feed direction and configured to control a flow rate of the liquid flowing into the discharge head; another liquid feeder configured to feed the liquid in the recovery tank to the storage tank when the detector detects that the amount of the liquid in the recovery tank exceeds a threshold amount; and a branch path connected to the liquid path that is configured to cause part of the liquid to branch from the liquid path, wherein the branch path connects an upstream side of the supply tank in the liquid feed direction to the recovery tank to mitigate pressure fluctuations of the liquid at the discharge head as the flow regulator controls the flow rate of the liquid flowing into the discharge head. ### Claim 12 (depends on 11) The liquid discharge device according to claim 11, wherein the flow regulator controls the flow rate of the liquid flowing into the discharge head to be constant without receiving an instruction from an external device. ### Claim 13 (depends on 11) The liquid discharge device according to claim 11, wherein the flow regulator includes a flow control valve, and wherein the flow regulator detects the flow rate of the liquid flowing into the discharge head and controls opening of the flow control valve on basis of the flow rate detected. ### Claim 14 (depends on 11) The liquid discharge device according to claim 11, wherein the supply tank is formed of a flexible member. ### Claim 15 (depends on 12) An image forming apparatus comprising the liquid discharge device according to claim 12. ### Claim 16 (depends on 11) A fabricating apparatus comprising the liquid discharge device according to claim 11.