Welding contact tip and diffuser
View Patent ↗A welding contact tip and diffuser assembly for use in a welding apparatus. The assembly includes an electrically conductive contact tip having a tapered exterior surface, a diffuser having a cavity with a tapered interior surface, and a releasable connection for holding the contact tip in the diffuser. The connection includes at least one detent element in either the diffuser or the contact tip, at least one recess forming a ramp in the other of the diffuser or contact tip, and at least one spring. The spring biases the detent element into the recess and against the ramp to generate an axial force against the ramp. The axial force tends to urge the tapered surfaces of the contact tip and diffuser into contact with one another.
1. A welding contact tip and diffuser assembly for use in a welding apparatus, said assembly comprising:
an electrically conductive contact tip comprising a tip body having a longitudinal axis, a back end, a forward end, an axial bore through the tip body for the feed of welding wire through the tip, and a tapered surface on an exterior of the tip body,
a diffuser for conducting electrical current and transmitting a shield gas, said diffuser comprising a diffuser body having a longitudinal axis, a back end adapted for connection to said welding apparatus, a forward end, and a cavity in the diffuser body extending from its forward end toward its back end, said cavity having a tapered surface, and
a connection between the diffuser and the contact tip for releasably holding the contact tip in the cavity of the diffuser with said tapered surfaces in contact for the conduction of electric current from the diffuser to the contact tip, said connection comprising at least one detent element in one of said diffuser and contact tip, at least one recess in the other of said diffuser and contact tip forming a ramp, and at least one spring for biasing said detent element into said recess and against the ramp to generate an axial force against the ramp tending to urge said tapered surfaces into contact with one another, said contact tip being releasable from the diffuser by exerting an axial force on the tip sufficient to overcome the force of said spring urging the detent element into said recess.
2. An assembly as set forth in claim 1 wherein said at least one detent element is carried by the diffuser and said recess is in said contact tip.
3. An assembly as set forth in claim 2 wherein said at least one detent element comprises a plurality of detent balls and said recess comprises a circumferential recess in an outer surface of the contact tip for receiving the balls.
4. An assembly as set forth in claim 2 wherein said at least one detent element is received in a generally radial bore in the body of the diffuser, and wherein said at least one spring comprises a resilient collar around the body of the diffuser and in contact with said at least one detent element for urging the element in a radial inward direction.
5. An assembly as set forth in claim 4 wherein said body of the diffuser further comprises a circumferential groove for receiving said resilient collar.
6. An assembly as set forth in claim 4 wherein said body of the diffuser further comprises a protrusion in contact with said resilient collar at a first end and a second end of said collar for limiting movement of said collar relative to said diffuser body.
7. An assembly as set forth in claim 1 wherein said ramp declines in a forward direction.
8. An assembly as set forth in claim 7 wherein said ramp comprises a flat surface declined in a forward direction at an angle in the range of approximately 20 to 60 degrees.
9. An assembly as set forth in claim 8 wherein said ramp further comprises a rounded surface adjacent to the bottom of the recess having a radius of curvature approximately equal to that of the detent ball.
10. An assembly as set forth in claim 1 wherein said tapered surfaces are located between said back end and said forward end of the diffuser body.
11. An assembly as set forth in claim 1 wherein the tapered surfaces are angled to generate a self-locking force.
12. An assembly as set forth in claim 1 wherein said tip and diffuser can be assembled without twisting the tip and diffuser relative to one another about either longitudinal axis.
13. A welding contact tip for use in a welding apparatus, said contact tip comprising an elongate body having a longitudinal axis, back and forward ends, an axial bore through the body for the feed of a continuous welding wire through the body, a tapered exterior surface on the body adapted for contact with a tapered interior surface on a diffuser when the contact tip is inserted into the diffuser, and a recess in an exterior surface of the body forming a ramp on the body adapted for engagement by at least one spring-biased detent element carried by said diffuser, said ramp being so configured that contact by said spring-biased detent element creates a force in an axial direction tending to urge said tapered surfaces toward one another.
14. A welding contact tip as set forth in claim 13 wherein said recess is located generally adjacent the back end of the tip between said tapered exterior surface and the back end of the tip.
15. A welding contact tip as set forth in claim 14 wherein said recess comprises a circumferential recess in the tip.
16. A welding contact tip as set forth in claim 13 wherein said ramp comprises a flat surface declined in a forward direction at an angle in the range of approximately 20 to 60 degrees.
17. A welding contact tip as set forth in claim 16 wherein said ramp further comprises a rounded surface adjacent to the bottom of the recess having a radius of curvature approximately equal to that of the detent element.
18. A welding diffuser for conducting electrical current and transmitting a shield gas in a welding operation, said diffuser comprising
a body having a longitudinal axis, a back end adapted for connection to said welding apparatus and a forward end,
a cavity in the diffuser body extending from its forward end toward its back end, said cavity having an interior tapered surface adapted for contact by an exterior tapered surface of a contact tip inserted in said cavity,
at least one generally radial bore in the body having a radial inner end communicating with said cavity and a radial outer end,
a detent element movable in said radial bore, and
a resilient collar around the body of the diffuser for urging the detent element radially inward in said bore toward a position in which the detent element is received in a recess in said contact tip thereby to releasably lock the contact tip in said diffuser.
19. A welding diffuser as set forth in claim 18 wherein said interior tapered surface extends from the forward end of the diffuser toward the back end of the diffuser.
20. A welding diffuser as set forth in claim 19 wherein said tapered surfaces are self-locking.
21. A welding diffuser as set forth in claim 18 wherein said body further comprises a circumferential groove for receiving said resilient collar.
22. A welding diffuser as set forth in claim 18 wherein said body further comprises a protrusion contacting said resilient collar at a first end and a second end of said collar for limiting the movement of said resilient collar relative to said body.
23. A welding contact tip and diffuser assembly for use in a welding apparatus, said assembly comprising:
an electrically conductive contact tip comprising a tip body having a longitudinal axis, a back end, a forward end, an axial bore through the tip body for the feed of welding wire through the tip, and a diffuser-contacting contact surface on an exterior of the tip body,
a diffuser for conducting electrical current and transmitting a shield gas, said diffuser comprising a diffuser body having a longitudinal axis, a back end adapted for connection to said welding apparatus, a forward end, and a cavity in the diffuser body extending from its forward end toward its back end, said cavity having a tip-contacting contact surface, and
a connection between the diffuser and the contact tip for releasably holding the contact tip in the cavity of the diffuser with said contact surfaces in contact for the conduction of electric current from the diffuser to the contact tip, said connection comprising at least one detent element in one of said diffuser and contact tip, at least one recess in the other of said diffuser and contact tip forming a ramp, and at least one spring for biasing said detent element into said recess and against the ramp to generate an axial force against the ramp tending to urge said contact surfaces into contact with one another, said contact tip being releasable from the diffuser by exerting an axial force on the tip sufficient to overcome the force of said spring urging the detent element into said recess.
24. An assembly as set forth in claim 23 wherein said at least one detent element is carried by the diffuser and said recess is in said contact tip.
25. An assembly as set forth in claim 24 wherein said at least one detent element comprises a plurality of detent balls and said recess comprises a circumferential recess in an outer surface of the contact tip for receiving the balls.
26. An assembly as set forth in claim 24 wherein said at least one detent element is received in a generally radial bore in the body of the diffuser, and wherein said at least one spring comprises a resilient collar around the body of the diffuser and in contact with said at least one detent element for urging the element in a radial inward direction.
27. An assembly as set forth in claim 26 wherein said body of the diffuser further comprises a circumferential groove for receiving said resilient collar.