# US 12,766,584 B2 · Diameter-expanding tool head and diameter-expanding method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,766,584 B2 - Document ID: US12766584B2 - Status: Granted - Kind: B2 - Application number: 18/452,186 - Filed: 2023-08-18 - Published: 2024-02-29 - Granted: 2026-10-20 - Earliest claimed: 2022-08-23 - Applicants: Cheng-Chia Peng - Inventors: Cheng-Chia Peng - Web page: https://patentgrep.com/patent/US12766584B2 ## CPC - B21D 41/021: {by means of tube-flaring hand tools} - B21D: WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL (working or processing of wire B21F) ## Abstract A diameter-expanding tool head and a diameter-expanding method thereof, the tool head comprises an expanding section forming convex portions and concave portions disposed at intervals on an outer peripheral surface, any one of the concave portions is formed between any two of the convex portions, each of the convex portions has a convex peak, the convex peak is a part farthest from an axis, each distance is equal, the convex peaks are connected to form a diameter-expanding surface spanning each of the concave portions. The expanding section is rotatably inserted into a channel of a body to be expanded, and is in discontinuous contact with the channel through the convex and concave portions, a diameter of at least a part of the body to be expanded is expanded to form a diameter-expanded channel, and an inner wall surface of the diameter-expanded channel is flush with the diameter-expanding surface. ## Claims ### Claim 1 A diameter-expanding tool head, the diameter-expanding tool head defining an axis, the diameter-expanding tool head defining a front end and a rear end relative to the axis, the diameter-expanding tool head comprising: an expanding section, the expanding section being formed from the front end toward the rear end relative to the axis, the expanding section being cylindrical, the expanding section being formed with an outer peripheral surface relative to the axis, the outer peripheral surface being a cylindrical surface, the outer peripheral surface being formed with a plurality of convex portions and a plurality of concave portions disposed at intervals, any one of the concave portions being formed between any two of the convex portions, each of the convex portions being an arcuate shape protruding outward relative to the axis, each of the convex portions having a convex peak, the convex peak of each of the convex portions being a part farthest from the axis, each distance being equal, a maximum outer diameter of the expanding section being located at any one of the convex peaks, the convex peak of each of the convex portions being axially connected relative to the axis to form a diameter-expanding surface, the diameter-expanding surface spanning each of the concave portions; and a blocking section connected to the expanding section, the blocking section being formed on the rear end relative to the axis, an outer diameter of the blocking section being larger than the maximum outer diameter of the expanding section, and a connection between one side surface of the blocking section and the expanding section radially forming a blocking surface relative to the axis. ### Claim 2 (depends on 1) The diameter-expanding tool head as claimed in claim 1, wherein any one of the convex portions and any one of the concave portions are horizontally annularly disposed on the outer peripheral surface of the expanding section from the front end to the rear end of the diameter-expanding tool head to form a horizontal extending direction, the horizontal extending direction is parallel to the convex portions and the concave portions respectively, an included angle is formed between the horizontal extending direction and the axis, the included angle is a right angle, a starting position of the horizontal extending direction is connected to an ending position of the horizontal extending direction, forming of any one of the convex portions and any one of the concave portions in the horizontal extending direction is continuous or discontinuous. ### Claim 3 (depends on 1) The diameter-expanding tool head as claimed in claim 1, wherein any one of the convex portions and any one of the concave portions are obliquely spirally disposed on the outer peripheral surface of the expanding section from the front end to the rear end of the diameter-expanding tool head to form an oblique extending direction, the oblique extending direction is parallel to the convex portions and the concave portions respectively, an included angle is formed between the oblique extending direction and the axis, the included angle is a non-right angle, a starting position of the oblique extending direction is not connected with an ending position of the oblique extending direction, the starting position is located at or near the front end, and the ending position is located at or near the rear end, forming of any one of the convex portions and any one of the concave portions in the oblique extending direction is continuous or discontinuous. ### Claim 4 (depends on 1) The diameter-expanding tool head as claimed in claim 1, wherein the convex portions do not intersect with one another and are parallel to one another, the concave portions do not intersect with one another and are parallel to one another, any one of the convex portions and any one of the concave portions do not intersect with each other and are parallel to each other, the maximum outer diameters are equal, the diameter-expanding surface does not intersect with the axis, the diameter-expanding surface is parallel to the axis, and the diameter-expanding surface is parallel to the outer peripheral surface. ### Claim 5 (depends on 1) The diameter-expanding tool head as claimed in claim 1, further comprising an assembling section connected with the blocking section, wherein the blocking section is formed with an assembling surface on another side surface of the blocking section opposite to the blocking surface, wherein the assembling section extends axially from the assembling surface relative to the axis, wherein an outer diameter of the blocking section is larger than an outer diameter of the assembling section, and wherein an end of the assembling section opposite to the blocking section defines the rear end of the diameter-expanding tool head. ### Claim 6 (depends on 1) The diameter-expanding tool head as claimed in claim 1, wherein the blocking section is further formed with a blocking edge, the blocking surface of the blocking section is axially formed with the blocking edge at a peripheral edge relative to the axis.