US3913170A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Door closer
Assignee: Miwa Lock KK
•
Filing: 1975-01-02
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Granted: 1975-10-21
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Expires: 1995-01-02
Abstract
Abstract A door closer for affording a controlled closing movement to a door including a return spring, an oil hydraulic piston and cylinder means, and a valve for generating a damping force when the door closers, said valve comprises a movable valve member for regulating oil flow through the valve, and a bimetal element connected with the movable valve member in response to the change in the temperature thereby attaining a substantially constant closing speed of the door irrespective to the change in the temperature.
Inventors
- 👤 Sunao Nakane
- 👤 Kiyoyasu Wake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:26
CPC Classifications
E; E05; E05F; E05F3/00; E05F3/04; E05Y; E05Y2201/00; E05Y2201/20; E05Y2201/23; E05Y2201/232; E05Y2201/40; E05Y2201/43; E05Y2201/448; E05Y2201/458; E05Y2900/00; E05Y2900/10; E05Y2900/13; E05Y2900/132
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
381 words
In a door closer, a housing having a cylinder formed therein and a piston slidably engaged in the cylinder to reciprocate axially thereof and define first and second chambers therein, means yieldably biasing the piston in one axial direction of the cylinder, means for interconnecting the piston with the door so that during opening of the door said means for interconnecting moves the piston in the other axial direction of the cylinder against the bias thereon, and means for damping the reciprocation of the piston in the one axial direction of the cylinder under the bias thereon when the door is released, including a hydraulic fluid charge in the cylinder, means defining a first fluid flow path and a second fluid flow path between said first and second chambers, check valve means in the first fluid flow path whereby the fluid can flow therethrough only from the second chamber to the first chamber, when the piston is reciprocated in the other axial direction of the cylinder, and throttle valve means in the second fluid flow path whereby the fluid flow from the first chamber to the second chamber is throttled at a variable rate when the piston is reciprocated in the one axial direction of the cylinder, said second fluid flow path including an outlet for the fluid in one wall of said first chamber, said throttle valve means including a bimetallic thermostatic element which is cantilevered into the first chamber from a point within the housing, an arcuate valve closure member, and means slidably mounting the arcuate valve closure member in the housing adjacent the outlet so that the closure member can slide circumferentially in relation to the outlet and can overlap the outlet to a variable extent, the free end of the bimetallic element being relatively pivotally interconnected with the arcuate value closure member rendering said arcuate valve closure member selfaligning with the wall surrounding said outlet so that deflection of the element in response to temperature variations in the fluid charge causes the closure member to move circumferentially in relation to the outlet and thereby to vary the extent of its overlap with the outlet, but Pressure differentials across the closure member do not cause counter deflections in the element which could distort the shape of the element.
Claim 2
Dependent Claim
381 words
In a door closer, a housing having a cylinder formed therein and a piston slidably engaged in the cylinder to reciprocate axially thereof and define first and second chambers therein, means yieldably biasing the piston in one axial direction of the cylinder, means for interconnecting the piston with the door so that during opening of the door said means for interconnecting moves the piston in the other axial direction of the cylinder against the bias thereon, and means for damping the reciprocation of the piston in the one axial direction of the cylinder under the bias thereon when the door is released, including a hydraulic fluid charge in the cylinder, means defining a first fluid flow path and a second fluid flow path between said first and second chambers, check valve means in the first fluid flow path whereby the fluid can flow therethrough only from the second chamber to the first chamber, when the piston is reciprocated in the other axial direction of the cylinder, and throttle valve means in the second fluid flow path whereby the fluid flow from the first chamber to the second chamber is throttled at a variable rate when the piston is reciprocated in the one axial direction of the cylinder, said second fluid flow path including an outlet for the fluid in one wall of said first chamber, said throttle valve means including a bimetallic thermostatic element which is cantilevered into the first chamber from a point within the housing, an arcuate valve closure member, and means slidably mounting the arcuate valve closure member in the housing adjacent the outlet so that the closure member can slide circumferentially in relation to the outlet and can overlap the outlet to a variable extent, the free end of the bimetallic element being relatively pivotally interconnected with the arcuate value closure member rendering said arcuate valve closure member selfaligning with the wall surrounding said outlet so that deflection of the element in response to temperature variations in the fluid charge causes the closure member to move circumferentially in relation to the outlet and thereby to vary the extent of its overlap with the outlet, but Pressure differentials across the closure member do not cause counter deflections in the element which could distort the shape of the element.
Claim 3
Dependent Claim
54 words
The door closer according to claim 1 wherein the rim of the outlet and the closure member are slidably engaged and are adapted in relation to one another so that they define an opening for passage of the fluid which varies non-arithmetically in area as the closure member reciprocates in relation to the outlet.
Claim 4
Dependent Claim
59 words
The door closer according to claim 2 wherein the outlet is defined by the end opening of a through-bore in the housing, and said through-bore has a shallow, laterally projecting recess therein at the end opening, which recess has a generally V-shaped plan configuration in the plane of the opening, and is in part covered by the closure member.
Claim 5
Dependent Claim
15 words
The door closer of claim 1 wherein the first flow path is through said piston.
Claim 6
Dependent Claim
28 words
The door closer of claim 1 wherein said valve closure member is slidable circumferentially along the inner surface of a cylindrical recess, said outlet opening through said surface.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |