Window operator

Abstract

A window operator has a prime mover for opening and closing of a window, with the prime mover being drivingly connected to a drive output member through an intermediate gear structure. A clutch device in the drive structure senses the torque applied to the drive output member in a window closing operation and a switch operable by the clutch is effective to deenergize the prime mover when the torque applied to the output member reaches a predetermined value. The switch can be adjustably located relative to the clutch whereby the predetermined value at which the motor will be deenergized may be varied in order to obtain a desired tension on a member connected to the closed sash of the window, such as a chain connected to the sash of a skylight window.

We claim: 
     
       1. A window operator for moving a window component between fully open and closed positions and any desired position therebetween, comprising: a rotatable drive output member;   a rotatable drive input member;   a gear train between said drive input and drive output members;   means for rotating said drive input member;   a switch for controlling operation of said rotating means;   means responsive to a closing torque applied to the rotatable drive output member in excess of a predetermined value for operating said switch to deenergize said rotating means;   a clutch associated with said drive output member;   spring means acting on said clutch to maintain a drive through said clutch, said clutch including a pair of clutch members urged toward each other by said spring means, said clutch members having .[.coating.]. .Iadd.coacting .Iaddend.stops to prevent rotation of the clutch members and gear train in response to an externally-applied window component opening force;   .[.coating.]. .Iadd.coacting .Iaddend.helical ramps on said clutch members which cause progressive separating movement therebetween when said closing torque exceeds the force of said spring means holding the clutch members against movement; and   means adjustably mounting said switch in the path of the clutch member which moves as the clutch members separate to establish said predetermined torque value.   
     
     
       2. A window operator as defined in claim 1 wherein said coacting stops comprise vertical surfaces disposed in abutting relation on each of said clutch members, whereby relative rotation between said members in a direction representative of a window opening direction is precluded. 
     
     
       3. A window operator as defined in claim 1 wherein said vertical surfaces are further adapted to provide fixed rotation of each of said clutch members when drive torque is internally-applied to said drive input members in a direction representative of a window opening. 
     
     
       4. A window operator comprising: a rotatable drive output member;   a selectively operable motor;   a speed-reducing gear train between said .[.drive input.]. .Iadd.motor .Iaddend.and .Iadd.said .Iaddend.drive output .[.members.]. .Iadd.member.Iaddend.;   a clutch in said gear train including a pair of separable clutch members;   means yieldably-holding said clutch members against said separating movement;   a torque-responsive coacting means on the clutch members for causing progressive increase in the separation of the clutch members against the action of the yieldable holding means in a direction representative of only closing the window as the torque applied to the output member increases above a certain amount;   a motor-controlling switch positioned in the path of one of the clutch members; and   means for adjustably positioning said switch whereby the amount of said torque effective to operate the switch can be set at a predetermined value .Iadd.to ensure that a minimum selected torque be applied to the output member to effect tight closing of the window.Iaddend..   
     
     
       5. A window operator for moving a window component between fully open and closed positions and any desired position therebetween comprising; a rotatable drive output member;   a rotatable drive input member;   a gear train between said drive input and drive output members;   means for rotating said drive input member;   a switch for controlling operation of said rotating means; and   means responsive to a closing torque applied to the rotatable drive output member in excess of a predetermined value for operating said switch to deenergize said rotating means, said responsive means including a clutch having a pair of clutch members urged toward each other by spring means, and anti-backdrive means adapted to prevent rotation of the clutch members and gear train in response to an externally-applied window component opening force.