Pre-deformed thermoplastics spring and method of manufacture
A thermoplastic spring and a method for manufacturing the thermoplastic spring are provided to reduce the effect of creep during use of the spring. The spring is molded and deformed to final dimensions by pre-inducing creep in the molded body.
1. A thermoplastic spring, comprising:
a thermoplastic body;
at least one non-deformed region in said body having dimensions established by molding of the body; and
at least one deformed region in said body, the deformed region extending fully across a cross-section of the body, the deformed region being deformed by stretching and having a first deformed dimension, in a stretched state, greater than the dimension thereof created by molding, the deformed region having a second deformed dimension in a non-stretched state greater than the dimension thereof created by molding and less than the dimension thereof in the stretched state;
said deformed dimension resulting from elongation beyond a final in-use dimension of the thermoplastic spring.
2. The thermoplastic spring of claim 1 , including a plurality of non-deformed regions.
3. The thermoplastic spring of claim 1 , including a plurality of deformed regions.
4. The thermoplastic spring of claim 1 , including a plurality of non-deformed regions and a plurality of deformed regions.
5. The thermoplastic spring of claim 1 , having at least one non-deformed node among multiple deformed regions.
6. The thermoplastic spring of claim 5 , including a series of alternating non-deformed nodes and deformed regions.
7. The thermoplastic spring of claim 1 , said deformed region including at least two strands.
8. The thermoplastic spring of claim 7 , said strands each having non-deformed nodes within the deformed regions thereof.
9. The thermoplastic spring of claim 8 , including bridges connecting at least some nodes from one strand to at least some nodes of the other strand.
10. An air hose support strap, comprising:
a monolithic, elastomeric, thermoplastic body;
end regions of said body having dimensions established by molding; and
an intermediate region between said end regions having a molded dimension and having final dimensions in a non-stretched state established by molding and subsequent stretching of the molded dimension to a larger dimension, at least a portion of said intermediate region extending fully across a cross-section of said body, the final dimensions being greater than the molded dimension and less than the stretched dimension.
11. The air hose support strap of claim 10 , said intermediate region having at least one non-deformed node therein thicker than deformed sections in said intermediate region.
12. The air hose support strap of claim 10 , said intermediate region including at least two strands.
13. The air hose support strap of claim 12 , said strands having alternating non-deformed nodes and deformed segments.
14. The air hose support strap of claim 13 , including bridges connecting at least some nodes from one strand to at least some nodes of the other strand.
15. A method for making a thermoplastic spring, comprising:
forming a spring body of thermoplastic material to a dimension less than a final dimension of the spring;
elongating at least a portion of the spring body to a dimension greater than the final dimension, wherein the elongation occurs, at least in part, fully across a cross-section of the spring body; and
releasing the elongated portion to a non-stretched state.
16. The method of claim 15 , said elongating performed by stretching.
17. The method of claim 15 , said elongating performed by stretching a first distance and releasing, followed by stretching a second distance.
18. The method of claim 17 , said first and second distances being different.
19. The method of claim 15 , said elongating including stretching and holding the at least a portion of the spring body in the stretched condition.
20. The method of claim 15 , said elongating including stretching at least a first time and a second time at different conditions of at least one of acceleration, distance and dwell time.