# US 8,739,586 B2 · Electrical liner actuator for lock > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,739,586 B2 - Document ID: US8739586B2 - Status: Granted - Kind: B2 - Application number: 13/551,678 - Filed: 2012-07-18 - Published: 2013-02-21 - Granted: 2014-06-03 - Earliest claimed: 2012-07-18 - Assignees: Locway Technology Co., Ltd. - Applicants: Mengxiao Yuan - Inventors: Mengxiao Yuan - Web page: https://patentgrep.com/patent/US8739586B2 ## CPC - E05B 47/026: {the bolt moving rectilinearly} - E05B 15/04: Spring arrangements in locks {(E05B3/065, E05B15/101, E05B15/143, E05C19/06 take precedence)} - F16F 1/04: Wound springs {(making springs by coiling wire B21F3/00)} - E05B 2015/0406: {wound in a cylindrical shape} - E05B 2047/0031: {of the elastic type} - Y10T 70/7102: And details of blocking system [e.g., linkage, latch, pawl, spring] - Y10T 70/7113: Projected and retracted electrically - Y10T 70/8027: Condition indicators - Y10T 292/1021: Motor - E05B: LOCKS; ACCESSORIES THEREFOR; HANDCUFFS - F16F: SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract The invention relates to an electrical linear actuator for a lock, which comprises a motor, a rotating shaft connected with the motor, a spring sleeved on the rotating shaft and a pin arranged on the rotating shaft and also comprises a slider, wherein the slider is provided with a frame capable of receiving the shaft and the spring; grooves for limiting the rotating shaft are formed on a wall; the spring comprises a first winding, end coils and second windings; the first winding is arranged in the middle part of the spring and takes the shape of a cylindrical spiral; the end coils are respectively arranged at both ends of the spring and coaxial with the first winding; the second windings are arranged between the first winding and the end coils, and circumscribed circles of the second windings are convex relative to the first winding; and third windings coaxial with the first winding can be arranged between the second windings and the end coils. ## Claims ### Claim 1 An electrical linear actuator for a lock, comprising: a motor (1), a rotating shaft (3) connected with the motor, a spring (4) sleeved on the rotating shaft and a pin (5) arranged in the middle part of the rotating shaft; also comprising: a slider (2), wherein the slider provided with a frame (20) capable of receiving the rotating shaft and the spring; grooves (23, 24) for limiting the radial displacement of the rotating shaft (3) formed on a wall of the frame (20); and the spring (4) comprising: a first winding (40), end coils (45, 46) and second windings (43, 44), in which the first winding (40) arranged in the middle part of the spring and takes the shape of a cylindrical spiral; the end coils (45, 46) arranged at both ends of the spring and coaxial with the first winding; the second windings (43, 44) arranged between the first winding and the end coils, and circumscribed circles of the second windings (43, 44) being convex relative to the first winding; and both ends of the second windings (43, 44) respectively connected with the first winding and third windings (41, 42), which are adjacent the end coils. ### Claim 2 (depends on 1) The electrical linear actuator for the lock according to claim 1, wherein the third windings are (41, 42) coaxial with the first winding and are also arranged between the second windings (43, 44) and the end coils (45, 46); and both ends of the third windings (41, 42) are respectively connected with the end coils and the second windings, which are adjacent to the third windings. ### Claim 3 (depends on 2) The electrical linear actuator for the lock according to claim 2, wherein the diameter of the first winding is less than that of the end coils (45, 46); and corresponding end coils (45, 46) and third windings (41, 42) form conical springs. ### Claim 4 (depends on 1) The electrical linear actuator for the lock according to claim 1, wherein the second windings (43, 44) of the spring (4) take the shape of circular rings of which the diameter is less than that of the first winding; and the spiral direction thereof is opposite to that of the first winding (40). ### Claim 5 (depends on 4) The electrical linear actuator for the lock according to claim 4, wherein the difference of the angle θ between centerlines of the projecting second windings (43, 44) of the spring (4) is between 70 degrees and 90 degrees. ### Claim 6 (depends on 4) The electrical linear actuator for the lock according to claim 4, wherein the second windings (43, 44) of the spring (4) are arranged in the form of central symmetry; and the difference of the angle θ between the centerlines of the projecting second windings (43, 44) of the spring (4) is 180 degrees. ### Claim 7 (depends on 2) The electrical linear actuator for the lock according to claim 2, wherein the second windings (43, 44) of the spring (4) are V-shaped; one side of each V-shaped second winding is tangential to the first winding (40) while the other side of the V-shaped second winding is tangential to one of the third windings (41, 42); and two sides tangential to the third windings are parallel to each other. ### Claim 8 (depends on 1) The electrical linear actuator for the lock according to claim 1, wherein the second windings (43, 44) of the spring (4) are V-shaped; and the diameter of circular arcs at the bottoms of the V-shaped second windings is less than that of the first winding (40). ### Claim 9 (depends on 8) The electrical linear actuator for the lock according to claim 8, wherein the difference of the angle θ between the centerline of the projecting second windings (43, 44) of the spring (4) is between 70 degrees and 90 degrees. ### Claim 10 (depends on 9) The electrical linear actuator for the lock according to claim 9, wherein notches (25, 26) are formed at corresponding positions of the frame (20) of the slider (2) and the second windings (43, 44); portions of the tops of V-shaped portions of the second windings are extended into the notches. ### Claim 11 (depends on 1) The electrical linear actuator for the lock according to claim 1, wherein the vertical distance from convex vertexes of the second windings (43, 44) to an axial line of the first winding (40) is more than the vertical distance from inner walls (21, 22) of the slider to the axial line of the first winding after the spring (4) is assembled into the slider. ### Claim 12 (depends on 1) The electrical linear actuator for the lock according to claim 1, wherein transition portions (47, 48) are formed between the second windings (43, 44) and the first winding (40); the helix angle of the transition portions is the sum of the helix angle α of the first winding (40) and an inclination angle β; and the inclination angle β is between 3 degree and 7 degree. ### Claim 13 (depends on 1) The electrical linear actuator for the lock according to claim 1, wherein the pin (5) is fixed in a hole (30) formed on the rotating shaft (3); one portion of the pin extended out of the rotating shaft has a smooth outer surface; and the extended portion is arranged above the first winding (40). ### Claim 14 (depends on 13) The electrical linear actuator for the lock according to claim 13, wherein the pin (5) is formed by bending a steel wire; bends (51) are formed at both ends of the pin; and both ends of the steel wire are disposed in the middle part of the pin. ### Claim 15 (depends on 14) The electrical linear actuator for the lock according to claim 14, wherein one steel wire end of the pin (5) is bent to form a gap (52) which forms an acute angle with a central axis of the pin. ### Claim 16 (depends on 13) The electrical linear actuator for the lock according to claim 13, wherein the pin (5) is formed by bending a steel wire; one end of the pin is a double bend (50) and the other end of the pin is a single bend (51); and both ends of the steel wire are disposed in the middle part of the pin. ### Claim 17 (depends on 16) The electrical linear actuator for the lock according to claim 16, wherein one steel wire end of the pin (5) is bent to form a gap (52) which forms an acute angle with a central axis of the pin. ### Claim 18 (depends on 1) The electrical linear actuator for the lock according to claim 1, wherein the grooves (23, 24) formed on a wall of the slider (2) are U-shaped grooves. ### Claim 19 (depends on 1) The electrical linear actuator for the lock according to claim 1, wherein a convex wing (27) is formed on an outer surface of the slider (2) and used to detect the position of the slider.