发明名称 |
Backflow prevention devices |
摘要 |
A backflow prevention device is disclosed which includes a spring operated check valve and a shielding member for protection of the spring from transverse fluid flow disturbances. The shielding member is preferably cylindrical in shape and surrounds the spring longitudinally about 40% to 90% of the extended spring length.
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申请公布号 |
US4132246(A) |
申请公布日期 |
1979.01.02 |
申请号 |
US19760710284 |
申请日期 |
1976.07.30 |
申请人 |
INTERNATIONAL TELEPHONE AND TELEGRAPH CORPORATION |
发明人 |
FRISEN, ROBERT A. |
分类号 |
E03C1/10;F16K15/06;(IPC1-7):F16K15/06 |
主分类号 |
E03C1/10 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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