Back to results
US 4,676,294 AGranted
Gate
OwnerRobert P. Bergerinventor
Life of this patent
Estimating the term…
Abstract
Gate is a wax structure for forming part of a wax master in investment casting of a dental prosthesis. The gate has a square feeder with a circular disc on each end. The square feeder reduces the cracking stresses between adjacent feeders to reduce unwanted fins, and the square shape aids in final cutoff of the cast prosthetic. In the wax master, one of the discs is secured to the prosthetic form and the other disc to the conventional reservoir bar. The disc shape aids in filleting to the form and bar.
Claims28
A dental prosthesis assembly comprising:
- a reservoir bar;
- at least one dental prosthesis structure positioned adjacent said reservoir bar and a gate interconnecting said dental prosthesis and said reservoir bar, the improvement comprising:
- said gate being configured with first and second members spaced from each other a predetermined distance and a feeder therebetween, said first member being secured to said dental prosthesis and said second member being secured to said reservoir, said feeder being a predetermined and uniform cross section and of smaller cross section than either said first or said second member.
The method of making a dental prosthesis comprising the steps of:
- mounting a wax gate structure having first and second members and a feeder of constant cross section and of fixed length therebetween with its first member secured and filleted to a wax master of a dental prosthesis;
- mounting the second member on a wax reservoir bar including filleting the second member to the reservoir bar;
- investing the wax, removing the wax from the investment, pouring metal into the investment and removing the investment to expose a metal dental prosthesis mounted on the gate on the reservoir bar;
- and
- cutting through the feeder in the gate to remove the metal dental prosthesis from the reservoir bar to avoid cutting the metal dental prosthesis.
2 more elements
A gate comprising:
- a first member for attachment to a dental prostheseis;
- a second member for attachment to a reservoir bar;
- and
- a feeder between said first and second members, said feeder being of constant cross section and of smaller cross section than said first and second members to define the feed area through said gate.
1 more element
Dependencies are inferred from the claim text.