Reinforcing ring for a plastic fitting and plastic fitting incorporating a reinforcing ring
A reinforcing and a plastic fitting incorporating such a reinforcing ring are disclosed. The reinforcing ring and plastic fitting have particular utility with respect to fire sprinkler heads in buildings. The reinforcing ring has a single starter thread which is integrally formed with a guide portion which guides a male part to be axially in line with the female fitting.
1. A reinforcing ring for a plastic fitting, comprising:
a first tubular portion;
a radial portion extending radially inwardly from a forward end of the tubular portion;
a guide portion extending rearwardly from a radially-inner region of the radial portion;
a starter thread extending radially inwardly from a rearward end of the guide portion; and
wherein the reinforcing ring is stamped from a metal sheet; and
wherein the starter thread is no more than 360° around the guide portion.
2. A reinforcing ring as defined in claim 1 wherein the guide portion is tubular.
3. A reinforcing as defined in claim 2 wherein the first tubular portion is conical.
4. A reinforcing ring as defined in claim 3 wherein the first tubular portion is conical at about 86° from horizontal.
5. A reinforcing ring as defined in claim 3 wherein the reinforcing ring is made of stainless steel.
6. A plastic fitting for receiving a threaded male part, comprising:
a plastic body having inner plastic threads for receiving the male part in threaded engagement; and
a reinforcing ring as defined in claim 3 wherein the first tubular portion of the reinforcing ring surrounds at least a portion of the plastic body.
7. A plastic fitting as defined in claim 6 wherein the starter thread of the reinforcing ring is aligned concentrically and axially with the threads of the plastic body.
8. A plastic fitting as defined in claim 7 wherein the guide portion of the reinforcing ring forms a guide portion of the fitting for guiding the male part to the starter thread.
9. A plastic fitting as defined in claim 8 the radial portion of the reinforcing ring forms a forward protective portion protecting the plastic body from contact with the male part as the male part initially engages the fitting.
10. A plastic fitting as defined in claim 9 the wherein plastic fitting is molded with the first tubular portion of the reinforcing ring positioned within and surrounded by the plastic body.
11. A plastic fitting as defined in claim 10 wherein there is a first inner thread and a last inner thread of the plastic body and the tubular portion of the reinforcing ring extends rearwardly to at least the last inner thread of the plastic body.
12. A plastic fitting as defined in claim 11 wherein the first tubular portion extends rearwardly beyond the last thread of the plastic body.
13. A plastic fitting as defined in claim 12 wherein the starter thread of the reinforcing ring forms a lead face of a first thread of the threads of the plastic body.
14. A reinforcing ring as defined in claim 1 wherein the guide portion is conical and extends rearwardly and inwardly.
15. A reinforcing ring as defined in claim 1 wherein the reinforcing ring is stamped from a stainless steel sheet.
16. A reinforcing ring as defined in claim 1 wherein each of the first tubular portion, radial portion and guide portion has a thickness and the thickness of each of the first tubular portion, radial portion and guide portion is relatively small compared to the diameter of the first tubular portion.
17. A plastic fitting for receiving a threaded male part, comprising:
a plastic body having inner plastic threads for receiving the male part in threaded engagement; and
a reinforcing ring as defined in claim 16 wherein the first tubular portion of the reinforcing ring surrounds at least a portion of the plastic body.
18. A plastic fitting as defined in claim 17 wherein:
the starter thread of the reinforcing ring is aligned concentrically and axially with the threads of the plastic body;
the guide portion of the reinforcing ring forms a guide portion of the fitting for guiding the male part to the starter thread;
the radial portion of the reinforcing ring forms a forward protective portion protecting the plastic body from contact with the male part as the male part initially engages the fitting;
plastic fitting is molded with the first tubular portion of the reinforcing ring positioned within and surrounded by the plastic body;
there is a first inner thread and a last inner thread of the plastic body and the tubular portion of the reinforcing ring extends rearwardly to at least the last inner thread of the plastic body;
the first tubular portion extends rearwardly beyond the last thread of the plastic body; and
the starter thread of the reinforcing ring forms a lead face of a first thread of the threads of the plastic body.