US3824901A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spring return for piston operator
Assignee: Shafer Valve Co
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Filing: 1973-01-18
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Granted: 1974-07-23
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Expires: 1993-01-18
Abstract
Abstract A spring return unit for actuating in one direction a linear piston operator which is actuated in the opposite direction by fluid pressure, said spring return being removably attachable to one end of the operator and comprising a fully enclosed preloaded compression spring compressible by an extension element on the end of the operator.
Inventors
- 👤 J Shafer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:51
CPC Classifications
F; F15; F15B; F15B15/00; F15B15/02; F15B15/06; F15B15/066; F16; F16K; F16K31/00; F16K31/12; F16K31/16; F16K31/163; F16K31/1635
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
129 words
In a linear fluid piston operator for a rotary valve having a tubular housing with removable end plates thereon, pistons in opposite ends of the housing, and means operatively connected to said pistons for imparting rotary movement to said valve when the pistons are moved linearly, the improvement comprising a spring return unit having a sealed housing mounted on one of said end plates and communicating with said tubular housing, a pre-loaded compression spring permanently enclosed within said spring housing, and a linear extension element connected to the adjacent piston and extending through said one end plate into said spring housing for compressing said spring as the piston is moved toward said spring housing, said one end plate having port means for controlling fluid pressure in said spring housing.
Claim 2
Dependent Claim
129 words
In a linear fluid piston operator for a rotary valve having a tubular housing with removable end plates thereon, pistons in opposite ends of the housing, and means operatively connected to said pistons for imparting rotary movement to said valve when the pistons are moved linearly, the improvement comprising a spring return unit having a sealed housing mounted on one of said end plates and communicating with said tubular housing, a pre-loaded compression spring permanently enclosed within said spring housing, and a linear extension element connected to the adjacent piston and extending through said one end plate into said spring housing for compressing said spring as the piston is moved toward said spring housing, said one end plate having port means for controlling fluid pressure in said spring housing.
Claim 3
Dependent Claim
39 words
In a linear fluid piston operator as described in claim 1, in which the extension element has a compression plate secured thereon within and having a lateral clearance from the spring housing and abutting one end of said spring.
Claim 4
Dependent Claim
44 words
In a linear fluid piston operator as described in claim 1, in which the outer end of said spring housing has a adjustable stop screw for abutting the outer end of said extension unit to lImit travel of said adjacent piston in one direction.
Claim 5
Dependent Claim
43 words
In a linear fluid piston operator as described in claim 2, in which the outer end of said spring housing has adjustable stop screw for abutting the outer end of said extension unit to limit travel of said adjacent piston in one direction.
Claim 6
Dependent Claim
39 words
In a linear fluid piston operator as described in claim 1, in which the end plate on which said sealed housing is interchangeable with said other end plate and has an opening therein through which said extension element extends.
Claim 7
Dependent Claim
41 words
In a linear fluid piston operator as described in claim 2, in which the end plate on which said sealed housing is mounted is interchangeable with said other end plate and has an opening therein through which said extension element extends.
Claim 8
Dependent Claim
41 words
In a linear fluid piston operator as described in claim 3, in which the end plate on which said sealed housing is mounted is interchangeable with said other end plate and has an opening therein through which said extension element extends.
Claim 9
Dependent Claim
41 words
In a linear fluid piston operator as described in claim 4, in which the end plate on which said sealed housing is mounted is interchangeable with said other end plate and has an opening therein through which said extension element extends.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-22 | 1978-01-21 | 1978-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-22 | 1982-01-21 | 1982-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-22 | 1986-01-21 | 1986-07-23 | $7700.00 | Window Closed / Lapsed |