The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 01, 1978
Filed:
Oct. 26, 1976
Robert D MacDonald, Phoenix, AZ (US);
Masco Corporation, Taylor, MI (US);
Abstract
An apparatus for automatically closing a door with respect to a fixed support adjacent thereto which includes a torsional spring, a one-way clutch mechanism and a swash plate hydraulic damper concealably retained within a compact housing. The housing is secured to either the door or the fixed support and a first rotatable portion of the one-way clutch is coupled to the other of either of the door or fixed support so that the first rotatable portion rotates in a first direction when the door is opened in the opposite direction when the door is closed. The torsional spring is at least partially disposed about the one-way clutch mechanism and has one end anchored to the housing and the other end secured for movement with the first rotatable portion. As the door is opened, the first rotatable portion is rotated in the first direction to wind up the torsional spring. When the door is released, the torsional spring unwinds to reverse the process and close the door. As the torsional spring unwinds, the first rotatable portion is driven in the opposite direction causing the one-way clutch mechanism to drive a second rotatable portion in the opposite direction as well. The swash plate hydraulic damper includes a plurality of piston chambers formed in the second rotatable portion, a closed hydraulic circuit interconnecting the piston chambers, and a piston element slidably disposed in each of the chambers for sealing the same and having an end portion extending therefrom. The hydraulic damper includes a wedge-shaped swash plate whose upper surface operatively engages the exposed end portions of the piston elements to restrict the rotation of the second rotatable portion so as to control the rate at which the spring unwinds to close the door. The resistance encountered by the pistons can be selectively varied by adjusting the rotational position of the swash plate with respect to the bottom of the housing. In the preferred embodiment disclosed herein, the compact housing forms the central portion of an ordinary hinge having one plate secured to the door and the other plate secured to the door casing although the housing could be mounted on or within the door itself. The compact assembly of the present invention enables a door to be automatically closed with a relatively constant closing force and provides a means whereby the force may be selectively adjusted.