# US 8,786,649 B2 · Print head assembly and printer using the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,649 B2 - Document ID: US8786649B2 - Status: Granted - Kind: B2 - Application number: 13/988,342 - Filed: 2011-11-01 - Published: 2013-10-31 - Granted: 2014-07-22 - Earliest claimed: 2010-11-19 - Assignees: Shangdong New Beiyang Information Technology Co., Ltd. - Applicants: Tao Gao; Xuejun Zhang; Qiangzi Cong; Tianxin Jiang; Min Yang - Inventors: Tao Gao; Xuejun Zhang; Qiangzi Cong; Tianxin Jiang; Min Yang - Web page: https://patentgrep.com/patent/US8786649B2 ## CPC - B41J 25/304: Bodily-movable mechanisms for print heads or carriages movable towards or from paper surface - B41J 2/32: using thermal heads - B41J 2/335: Structure of thermal heads - B41J 3/60: for printing on both faces of the printing material - B41J 11/0095: {Detecting means for copy material, e.g. for detecting or sensing presence of copy material or its leading or trailing end} - B41J 15/042: {for loading rolled-up continuous copy material into printers, e.g. for replacing a used-up paper roll; Point-of-sale printers with openable casings allowing access to the rolled-up continuous copy material} - B41J 25/34: Bodily-changeable print heads or carriages - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## Abstract A print head assembly and a printer using the same are disclosed. The print head assembly includes: a bracket, a print head and an elastic element. The bracket includes a first bracket body having a cavity and a lid covered on the opening of the cavity. A window is opened on the first bracket body. The print head is accommodated in the cavity of the first bracket body and hinged to the first bracket body via a first rotary shaft. The surface of a heating element of the print head is matched with the window and faces an outside paper pressing roller. The elastic element biases towards the print head so as to make the surface of the heating element of the print head have a tendency to extend outside the window. The print head assembly is capable of being detached as a whole, thus the requirements of performing single-sided printing and duplex printing in the same printer is achieved. ## Claims ### Claim 1 A print head assembly, comprising: a bracket, which is detachably connected with an outside frame, comprises a first bracket body having a cavity and a lid covered on the opening of the cavity of the first bracket body, wherein on the first bracket body a window is opened; a print head, which is accommodated in the cavity of the first bracket body and hinged to the first bracket body via a first rotary shaft, wherein the surface of a heating element of the print head is matched with the window and faces an outside paper pressing roller; and an elastic element, which biases towards the print head so as to make the surface of the heating element of the print head have a tendency to extend outside the window. ### Claim 2 (depends on 1) The print head assembly according to claim 1, wherein the print head assembly further comprises a transition socket arranged on the bracket and pluggably matched with an outside plug, wherein the print head is electrically connected to corresponding pins of the transition socket. ### Claim 3 (depends on 2) The print head assembly according to claim 2, wherein the print head assembly further comprises a sensor arranged on the first bracket body for detecting printing paper, wherein the sensor is electrically connected to corresponding pins of the transition socket. ### Claim 4 (depends on 2) The print head assembly according to claim 2, wherein the lid comprises a second bracket body and a third bracket body; the transition socket is arranged on a convert board, and the convert board is fixedly connected to the second bracket body; one end of the elastic element presses against the third bracket body, while the other end presses against the print head. ### Claim 5 (depends on 1) The print head assembly according to claim 1, wherein the print head assembly further comprises a print head lifting mechanism, wherein the print head lifting mechanism comprises a driving element arranged inside the bracket and an adjusting element driven by the driving element; the print head is fixedly connected with a press rod pressing against the adjusting element. ### Claim 6 (depends on 5) The print head assembly according to claim 5, wherein the adjusting element is a cam, and the driving element is a motor. ### Claim 7 (depends on 1) A printer, comprising: a fixed frame, which has a paper holder for accommodating printing paper; a moveable frame, which is hinged with the fixed frame and could be opened or closed relative to the fixed frame; and a first side printing mechanism and a second side printing mechanism, which are arranged along a paper passage to respectively print on the front side and back side of paper, wherein the first side printing mechanism comprises a first paper pressing roller arranged on the fixed frame and a first print head assembly arranged on the moveable frame; and the second side printing mechanism comprises a second print head assembly arranged on the fixed frame and a second paper pressing roller arranged on the moveable frame; wherein at least one of the first print head assembly and the second print head assembly is the print head assembly according to claim 1 capable of being detached as a whole. ### Claim 8 (depends on 7) The printer according to claim 7, wherein the first print head assembly is capable of being detached as a whole. ### Claim 9 (depends on 8) The printer according to claim 8, wherein the second print head assembly comprises a print head pivotally connected with the fixed frame through a second rotary shaft and an elastic element biasing the print head towards the second paper pressing roller. ### Claim 10 (depends on 8) The printer according to claim 8, wherein the first bracket body of the first print head assembly is provided on both sides thereof with locating protrusions; the moveable frame is provided with locating grooves matched with the locating protrusions; and the fixed frame is provided with locating grooves for adapting the locating protrusion. ### Claim 11 (depends on 10) The printer according to claim 10, wherein the locating protrusions are formed by shaft ends of the first rotary shaft extending outside two sides of the first bracket body. ### Claim 12 (depends on 1) A printer, comprising the print head assembly according to claim 1, wherein the print head assembly is arranged on a frame. ### Claim 13 (depends on 12) The printer according to claim 12, wherein the print head assembly further comprises a transition socket arranged on the bracket and pluggably matched with an outside plug, wherein the print head is electrically connected to corresponding pins of the transition socket. ### Claim 14 (depends on 13) The printer according to claim 13, wherein the print head assembly further comprises a sensor arranged on the first bracket body for detecting printing paper, wherein the sensor is electrically connected to corresponding pins of the transition socket. ### Claim 15 (depends on 13) The printer according to claim 13, wherein the lid comprises a second bracket body and a third bracket body; the transition socket is arranged on a convert board, and the convert board is fixedly connected to the second bracket body; one end of the elastic element presses against the third bracket body, while the other end presses against the print head. ### Claim 16 (depends on 12) The printer according to claim 12, wherein the print head assembly further comprises a print head lifting mechanism, wherein the print head lifting mechanism comprises a driving element arranged inside the bracket and an adjusting element driven by the driving element; the print head is fixedly connected with a press rod pressing against the adjusting element.