초록 ▼

A manually operable impact tool is provided that includes an elongated rigid handle and an impact head disposed at one longitudinal end portion of the handle structure. A cushioning grip is disposed over a second longitudinal end portion of the handle structure. The cushioning grip includes an inner

A manually operable impact tool is provided that includes an elongated rigid handle and an impact head disposed at one longitudinal end portion of the handle structure. A cushioning grip is disposed over a second longitudinal end portion of the handle structure. The cushioning grip includes an inner layer of thermoplastic rubber having a Shore A durometer in the range of about 10 to about 40, and an outer layer of thermoplastic rubber disposed over the inner layer having a Shore A durometer in the range of about 55 to about 90.

대표청구항 ▼

1. A manually operable impact tool comprising: an elongated handle;an impact head disposed at one longitudinal end portion of the handle;the handle including an internal core structure comprising a cross-section in the form of an I-beam, and a cushioning grip disposed over said core structure, the c

1. A manually operable impact tool comprising: an elongated handle;an impact head disposed at one longitudinal end portion of the handle;the handle including an internal core structure comprising a cross-section in the form of an I-beam, and a cushioning grip disposed over said core structure, the cushioning grip comprising: an inner layer of thermoplastic rubber having a Shore A durometer in the range of about 10 to about 40, the inner layer being in direct contact with the internal core structure;an outer layer of thermoplastic rubber disposed over the inner layer and having a Shore A durometer in the range of about 55 to about 90;wherein the inner layer is directly bonded to the outer layer, and, upon impact of the head, the inner layer substantially dampens torsional movement transmitted from the I-beam of the internal core structure to the outer layer, andwherein 4 degrees of angular displacement of the impact head relative to the outer layer applies a torque of less than about 47 in-lbs to the outer layer. 2. The manually operable impact tool of claim 1, wherein the inner layer of thermoplastic rubber has a Shore A durometer of about 30 to about 40. 3. The manually operable impact tool of claim 2, wherein the outer layer of thermoplastic rubber has a Shore A durometer of about 55 to about 65. 4. The manually operable impact tool of claim 1, wherein the inner layer of thermoplastic rubber has a Shore A durometer of about 35. 5. The manually operable impact tool of claim 1, wherein the I-beam of the core structure comprises an end portion having a plurality of longitudinally extending, parallel and spaced tines embedded in the inner layer of thermoplastic rubber having the Shore A durometer in the range of about 10 to about 40, and wherein torsional movement of the tines about a longitudinal axis is received and dampened by the inner layer to thereby reduce transmission of torsional forces imparted to the outer layer. 6. The manually operable impact tool of claim 5, wherein the tines comprise at least one opening therethrough for receiving the inner layer of thermoplastic rubber having the Shore A durometer in the range of about 10 to about 40. 7. The manually operable impact tool of claim 1, wherein the outer layer of thermoplastic rubber has a Shore A durometer of about 55 to about 65. 8. The manually operable impact tool of claim 1, wherein the outer layer of thermoplastic rubber has a Shore A durometer of about 60. 9. The manually operable impact tool of claim 1, wherein the inner layer of thermoplastic rubber is a solid non-foamed material. 10. A method for making a manually operable impact tool comprising an elongated core with at least one opening therethrough and a cushioning grip, the grip substantially absorbing torque imparted to the core upon impact of the tool, the method comprising: providing an impact head at a first longitudinal end of the core;covering a portion of said core with a first layer of thermoplastic rubber having a Shore A durometer in the range of about 10 to about 40, the first layer of thermoplastic rubber embedded in the at least one opening of the core; andsubstantially covering the first layer of thermoplastic rubber by directly bonding a second layer of thermoplastic rubber on the first layer, the second layer of thermoplastic rubber having a Shore A durometer in the range of about 55 to 90,wherein 4 degrees of angular displacement of the impact head relative to the outer layer applies a torque of less than about 47 in-lbs to the outer layer. 11. The method of claim 10, wherein the first layer of thermoplastic rubber has a Shore A durometer of about 30 to about 40. 12. The method of claim 10, wherein the first layer of thermoplastic rubber has a Shore A durometer of about 35. 13. The method of claim 10, wherein the second layer of thermoplastic rubber has a Shore A durometer of about 55 to about 65. 14. The method of claim 10, wherein the second layer of thermoplastic rubber has a Shore A durometer of about 60. 15. The method of claim 10, wherein the first layer of thermoplastic rubber is a solid non-foamed material. 16. A method according to claim 10, wherein the internal core comprises a cross-section in the form of an I-beam, and wherein the grip substantially absorbs torque imparted to the I-beam upon impact of the tool. 17. A manually operable hammer comprising: an elongated handle;an impact head disposed at one longitudinal end portion of the handle;said handle including an internal core structure, the internal core structure comprising a cross-section in the form of an I-beam and having a pair of longitudinally extending, parallel and spaced tines, and a cushioning grip disposed over said internal core structure, the tines disposed generally along opposite sides of a longitudinal axis of the core structure, the cushioning grip comprising: a soft inner layer of a solid, non-foamed thermoplastic rubber having a Shore A durometer in the range of about 10 to about 40, the inner layer being in direct contact with the internal core structure;an outer layer of thermoplastic rubber disposed over the inner layer, the outer layer being harder than the inner layer;the inner layer being directly bonded to the outer layer,wherein the tines are embedded in the inner layer such that torsional movement of the I-beam and the tines about the longitudinal axis is received and dampened by the inner layer to thereby reduce transmission of torsional forces imparted to the outer layer, andwherein 4 degrees of angular displacement of the impact head relative to the outer layer applies a torque of less than about 47 in-lbs to the outer layer. 18. The manually operable impact tool of claim 1, wherein the inner layer and outer layer are chemically bonded to each other. 19. The manually operable hammer of claim 17, wherein torsional movement of the tines torsionally compresses the inner layer of non-foamed thermoplastic rubber. 20. The manually operable impact tool of claim 1, wherein the internal core structure has at least one opening therethrough for receiving the inner layer of thermoplastic rubber having the Shore A durometer in the range of about 10 to about 40. 21. The manually operable hammer of claim 17, wherein the internal core structure has at least one opening therethrough for receiving at least a part of the inner layer of thermoplastic rubber having the Shore A durometer in the range of about 10 to about 40. 22. The manually operable hammer of claim 17, wherein the outer layer has a Shore A durometer in the range of about 55 to about 90. 23. The manually operable hammer of claim 17, wherein the outer layer has a Shore A durometer of about 55 to about 65. 24. A manually operable impact tool comprising: an elongated handle;an impact head disposed at one longitudinal end portion of the handle;the handle including an internal core structure comprising a longitudinal axis, and a cushioning grip disposed over said core structure, the cushioning grip comprising: an inner layer of thermoplastic rubber having a Shore A durometer in the range of about 10 to about 40;an outer layer of thermoplastic rubber disposed over the inner layer and having a Shore A durometer in the range of about 55 to about 90;wherein, upon impact of the head, the inner layer substantially dampens torsional movement transmitted from the internal core structure to the outer layer,wherein the core structure is permitted to twist slightly about the longitudinal axis without a corresponding degree of twist of the outer layer, andwherein 4 degrees of angular displacement of the impact head relative to the outer layer applies a torque of less than about 47 in-lbs to the outer layer. 25. The manually operable impact tool according to claim 24, wherein the inner layer is in direct contact with the internal core structure. 26. The manually operable impact tool according to claim 25, wherein the inner layer is in directly bonded to the outer layer. 27. The manually operable impact tool according to claim 24, wherein the inner layer is in directly bonded to the outer layer.