# US 11,994,178 B2 · Universal joint > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,994,178 B2 - Document ID: US11994178B2 - Status: Granted - Kind: B2 - Application number: 17/400,655 - Filed: 2021-08-12 - Published: 2022-03-17 - Granted: 2024-05-28 - Earliest claimed: 2020-09-17 - Assignees: Re-Dai Precision Tools Co., Ltd. - Applicants: Re-Dai Precision Tools Co., Ltd. - Inventors: Yi-Chiu Chou - Web page: https://patentgrep.com/patent/US11994178B2 ## CPC - B25B 23/0014: {Screwdriver- or wrench-heads provided with cardan joints or the like} - F16D 3/221: the rolling members being located in sockets in one of the coupling parts - B25B 13/481: {for operating in areas having limited access} - B25B 23/0028: {Angular adjustment means between tool head and handle} - B25B 23/0035: {Connection means between socket or screwdriver bit and tool} - F16D 3/185: {radial teeth connecting concentric inner and outer coupling parts} - F16D 2001/102: {the torque is transmitted via polygon shaped connections} - B25B: TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING, OR HOLDING - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES ## Abstract A universal joint includes a socket member and a driving member. The socket member includes a receiving hole, and an inner periphery of the receiving hole is formed with first evading portions and first abutting portions staggered with each other to cause the first abutting portions not connected to each other. Each first abutting portion is provided with a first abutting face, a second abutting face, and an adjacent edge formed between the first abutting face and the second abutting face. One side of the adjacent edge forms an adjacent edge angle being greater than 177 degrees and less than 180 degrees. The driving member includes a rounded base arranged in the receiving hole and a driving column opposite to the rounded base. ## Claims ### Claim 1 A universal joint comprising: a socket member defining a first end and a second end opposite the first end and including a receiving hole axially extending inward from the second end along a first reference axis, wherein an inner periphery of the receiving hole is formed with a plurality of first evading portions and a plurality of first abutting portions respectively extending linearly along a direction parallel to the first reference axis and staggered with each other to cause the plurality of first abutting portions not connected to each other, wherein each of the plurality of first abutting portions is provided with a first abutting face, a second abutting face connected to the first abutting face, and an adjacent edge formed between the first abutting face and the second abutting face and extending along the direction parallel to the first reference axis, and wherein one side of the adjacent edge opposite to the first reference axis forms an adjacent edge angle being greater than 177 degrees and less than 180 degrees; and a driving member axially extending along a second reference axis and having a rounded base arranged in the receiving hole and a driving column opposite to the rounded base. ### Claim 2 (depends on 1) The universal joint as claimed in claim 1, wherein the adjacent edge angle is 178 degrees. ### Claim 3 (depends on 1) The universal joint as claimed in claim 1, wherein any one of the plurality of first evading portions is in the shape of a circular arc on a reference plane perpendicular to the first reference axis, wherein one side of the first abutting face opposite to the second abutting face is connected to one of the plurality of first evading portions, and wherein one side of the second abutting face opposite to the first abutting face is connected to another one of the plurality of first evading portions. ### Claim 4 (depends on 3) The universal joint as claimed in claim 3, wherein an outer periphery of the rounded base forms a plurality of second evading portions and a plurality of second abutting portions staggered with each other around the second reference axis, wherein the plurality of second evading portions corresponds to the plurality of first evading portions, wherein the plurality of second abutting portions corresponds to the plurality of first abutting portions, wherein any one of the plurality of second evading portions is in the shape of a circular arc on a reference plane perpendicular to the second reference axis, and wherein any one of the plurality of second abutting portions is in the shape of a straight line on a reference plane perpendicular to the second reference axis. ### Claim 5 (depends on 4) The universal joint as claimed in claim 4, wherein the circular arc of any one of the plurality of first evading portions on the reference plane perpendicular to the first reference axis is a partial line segment of a reference circle, wherein a center of the reference circle is on the first reference axis, and wherein the number of the plurality of first evading portions, the number of the plurality of the plurality of first abutting portions, the number of the plurality of second evading portions, and the number of the plurality of second abutting portions are six, respectively. ### Claim 6 (depends on 5) The universal joint as claimed in claim 5, wherein an inner wall of the receiving hole is recessed with an annular slot extended around the first reference axis and located adjacent to an opening at the second end of the receiving hole, and wherein a retaining ring is arranged in the annular slot. ### Claim 7 (depends on 5) The universal joint as claimed in claim 5, wherein the driving member further has a neck formed between the rounded base and the driving column and adjacent the rounded base, wherein the retaining ring is located between the neck and the rounded base, and wherein a maximum width of the rounded base in a radial direction of the second reference axis is greater than a minimum width of the retaining ring in a radial direction of the first reference axis.