Drive assembly for door operator

US4564098A · kind A · utility

Assignee

• Hormann KG · DE

Inventor

• Michael Hormann · Bodenwerder, DE

Key dates

• Filing date: Jun 9, 1982
• Grant date: Jan 14, 1986
• Expiry date: Jun 9, 2002

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H2007/0874
• WIPO field: Civil engineering
• WIPO sector: Other fields

Abstract

A door operated drive assembly comprising an electric drive motor mechanically connected to a door pulling device by a transmission in the form of a belt drive or the like, utilizes an extension of a plate that is swingable in response to deviations of application pressure of the drive belt on belt guide pulleys carried thereby to trigger a switching arrangement utilized to trigger stopping or reversal of the drive motor. In order to make actuation of the switching arrangement a function of the degree of pressure applied by the drive belt, the plate is elastically loaded toward a middle position of its range of swingable movement. The elastic loading of the plate in accordance with a first embodiment is by way of two-arm springs positioned at opposite sides thereof, and in a second embodiment is produced by helical springs which act via actuators, on opposite sides of the plate extension. In both embodiments, the extension reaches to a position adjacent the switching arrangement, but, in the first embodiment, the extension comprises a pair of shields and the switching arrangement comprises a single photoelectric arrangement disposed therebetween, while, in the second embodiment, th…