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(11) | EP 0 252 554 A3 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Automatic door closer |
| (57) A door closer in the form of a floor spring has two coaxial cams (4 and 5) fastened
to its door spigot (3). One cam (4) acts via a roller (6) on the rod (7) of a restoring
spring unit (8). The other cam (5) acts via a roller (9) and lever (10) on the rod
(13) of a damper/assist unit (14). This unit (Fig 4) has a spring (25) which acts
on a piston (24) arranged to drive oil through a hydraulic circuit (26) in which there
is an automatic throttle (27) (Fig 5). The shape of the second cam (5) is such that
as soon as the door is "cracked" the force of the spring (25) in the damper/assist
unit (14) acts to assist the door to open in opposition to the spring in the restoring
unit (8). The throttle (27) is arranged to apply no significant damping to the movement
of the piston (24) in this direction. However, when the door is released and closes
under the force of the spring in the restoring unit (8) there is a reversal of the
flow direction in the hydraulic circuit (26) as the rod (13) of damper/assist unit
(14) is pushed in, and the throttle (27) is arranged to apply a significant damping
action to the piston (24) in this direction. |