Weight-lifting apparatus and method of assembling same
View Patent ↗A fixed weight/permanent weight-lifting apparatus including dumbbells and barbells is provided that have an elongated shaft with a centrally located handle and ends having a smaller diameter than the handle, a pre-coated head welded to each of these ends with a centrally located channel connecting its inner face and its outer face and a counter bore machined into its outer face of the head forming an inner collar. The channel has a diameter sufficient to receive the portion of the end of said shaft that extends beyond the inner collar. Each of the inner collars are joined to that portion of the end that extends beyond the collar.
1. Weight-lifting apparatus comprising:
a) an elongated shaft including a centrally located handle and ends having a smaller diameter than the handle;
b) a pre-coated head welded to each end of said shaft and having a centrally located channel extending from its inner face towards its outer face and a counter bore machined into its outer face forming a groove and an inner collar between the channel and the groove and protruding away from the head, the channel has a diameter sufficient to receive the end of said shaft that extends beyond the inner collar; and
c) a welded joint around each circumference of the inner collars and each of the portions of the end that extends beyond the collar.
2. The weight-lifting apparatus of claim 1 , wherein a cap for each of the heads is mounted over the counter bore to cover the counter bore and the channel.
3. The weight-lifting apparatus of claim 1 , wherein stepped sections are positioned between the handle and the ends, the sections having a smaller diameter than the handle and a larger diameter than the ends.
4. The weight-lifting apparatus of claim 1 , wherein said shaft and said heads are constructed of steel.
5. The weight-lifting apparatus of claim 4 , wherein said steel is a low carbon, weldable steel.
6. The weight-lifting apparatus of claim 1 , wherein the heads are pre-coated with a pliable material selected from the group consisting of rubber, polyurethane, polyvinyl and mixtures thereof.
7. The weight-lifting apparatus of claim 1 , wherein the handle is knurled.
8. The weight-lifting apparatus of claim 2 , wherein said cap is constructed of a pliable material.
9. The weight-lifting apparatus of claim 1 , wherein each of said heads is constructed of a solid block of metal.
10. The weight-lifting apparatus of claim 1 , wherein the inside edge of each of the collars is chamfered and each of the portions of the end of said shaft that extends beyond the collar is chamfered to correspond to the chamfer on the collar, and said head has a tensile strength in the range of about 55,000 to about 75,000 psi.
11. A method of assembling weight-lifting apparatus comprising the steps of:
a) providing:
i) an elongated shaft including a centrally located handle and ends having a smaller diameter than said shaft, and
ii) a pre-coated head welded to each end of said shaft and having a centrally located channel extending from its inner face towards its outer face and a counter bore machined into its outer face forming a groove and an inner collar between the channel and the groove and protruding away from the head, the channel has a diameter sufficient to receive the end of said shaft that extends beyond the inner collar;
b) pressing each of said heads onto the end of said shaft so that a portion of the end of said shaft extends from the inner face of said head to beyond the inner collar; and
c) welding a joint to join each circumference of the inner collars with each of the portions of the ends of said shaft extending beyond the inner collar.
12. The method of claim 11 , wherein a cap is mounted on each of said heads to cover the counter bore and the channel.
13. The method of claim 11 , wherein stepped sections are positioned between the handle and the ends, the sections having a smaller diameter than the handle and a larger diameter than said ends.
14. The method of claim 11 wherein said shaft and said heads are constructed of steel.
15. The method of claim 14 , wherein said steel is a low carbon, weldable steel.
16. The method of claim 11 wherein the heads are pre-coated with pliable material selected from the group consisting of rubber, polyurethane, polyvinyl and mixtures thereof.
17. The method of claim 11 , wherein the handle is knurled.
18. The method of claim 11 , wherein the counter bore is machined into the head, the counter bore is masked, the head is coated with a pliable material and the mask is removed prior to step (b).
19. The method of claim 11 , wherein the inside edge of each of the collars is chamfered and each of the portions of the ends of said shaft that extends beyond the collar is chamfered to correspond to the chamfer on the collar.