Revolving doors

• US 4,154,023 A
• Filed: 06/06/1977
• Issued: 05/15/1979
• Est. Priority Date: 12/07/1976
• Status: Expired due to Term

• Current Assignee: BWN Industries Pty Limited
• Original Assignee: BWN Industries Pty Limited
• Inventors: Carroll, Noel
• Primary Examiner(s): Kannan, Philip C.
• Application Number:
  US05/803,670
• Time in Patent Office: 708 Days
• Field of Search: 49/32, 49/43, 49/42, 49/29, 49/28, 49/27, 49/334, 318/210, 318/613
• US Class Current: 49/32
• CPC Class Codes: E05D 15/02 for revolving wings
• CPC Class Codes: E05F 15/608 for revolving wings
• CPC Class Codes: E05Y 2900/132 Doors

Abstract

A revolving door comprising at least one upright door element arranged in outwardly extending disposition about an upright axis of revolution, motor means being provided together with control means operable to position the door at a first rotational disposition from which, when the door is turned in one direction by a user pushing against said door element, power assistance is given to the door to effect rotation thereof; limit means being provided to cause the door to then come to rest at said first rotational disposition, in the absence of continued pushing by said user, after movement of the door under action of said motor means.

Claims

1. A revolving door comprising at least one upright door element arranged in outwardly extending disposition about an upright axis of revolution, motor means being provided together with control means operable to position the door at a first rotational disposition from which, when the door is turned in one direction by a user pushing against said door element, power assistance is given to the door to effect rotation thereof wherein said control means includes first means responsive, upon movement of the door from said first rotational disposition in said one direction, to cause operation of said motor means to effect said power assistance for a predetermined time, limit means being provided to cause the door to then come to rest at said first rotational disposition, in the absence of continued pushing by said user, after movement of the door under action of said motor means, wherein said control means further includes second means responsive to positioning of said door at a second rotational disposition, advanced in said one direction from said first rotational disposition, to initiate operation of said limit means, wherein said motor means includes a split phase capacitor start induction motor and said first means includes a timing circuit and a first switch operable upon said movement of the door from said first rotational disposition to initiate operation of said timing circuit, said timing circuit operating to then apply electrical current from an electric supply to one winding of said motor to cause said operation thereof for said predetermined period, wherein said second means includes a second switch operated upon positioning of said door at said second rotational disposition, to operate said limit means, said limit means comprising said motor, said second means operating in response to operation of said second switch means to apply said supply to said one winding of said motor and a unidirectional current from said supply to the other winding thereof whereby said motor operates at low speed and acts as a brake, wherein said first and second switches are arranged to be operated by a cam which is rotated by the door during use thereof, and wherein said first and second switches have operating arms which extend towards and are resiliantly biased towards the cam periphery and the cam has a portion extending over most of its periphery, which portion is of constant radius, and a single outward lobe, the free ends of the arms being positioned such that at said first rotational disposition the lobe is positioned therebetween so that neither arm is moved substantially radially outwardly from rest positions thereof and neither switch is operated, said cam outwardly pressing the arm of the first switch during said turning of the door in said one direction from said first rotational disposition to momentarily operate the said first switch and outwardly pressing the arm of the second switch towards the end of a full revolution of the door to operate the second switch, the speed of said motor when acting as said brake being such as to normally prevent the door and cam from moving in said one direction under its own acquired momentum so far past the location at which the second switch becomes inoperative as to initiate operation of said first switch, unless the door is so moved by a user.

2. A revolving door as claimed in claim 1, wherein said time period is such that, by normal operation of the door, the said power assistance is provided to the door for rotation thereof over an angular extent of 90 to 180 degrees from said first rotational disposition and said second rotational disposition corresponds to a location less than but substantially equal to 360 degrees from said first rotational disposition in said one direction.

3. A revolving door as claimed in claim 1 wherein an upright outer edge of said door element away from said axis is provided with an inwardly depressible edge strip connected to switch means, said switch means being incorporated into an electric circuit of said control means for said motor means whereby to effect stopping of the door element during rotation thereof in the event of depression of the edge strip inwardly towards said axis whereby if an object or person should become caught between the edge and an upright edge of an entrance surround for the door, the strip will be depressed causing the door to stop.

4. A revolving door as claimed in claim 1 wherein an upright outer edge of said door element away from said axis is provided with an inwardly depressible edge strip connected to switch means, said switch means being incorporated into an electric circuit of said control means for said motor means whereby to effect stopping of the door element during rotation thereof in the event of depression of the edge strip inwardly towards said axis whereby if an object or person should become caught between the edge and an upright edge of an entrance surround for the door, the strip will be depressed causing the door to stop;

said switch means being connected to effect said stopping by applying in-phase alternating currents to the two windings of the motor for at least a predetermined time period.

5. A revolving door as claimed in claim 4 wherein said switch means is connected to operate a timer which effects said applying in-phase alternating current for a short time period, whereafter the door is again conditioned for normal operation.

6. A revolving door as claimed in claim 1 wherein said control means includes switch means operable to cause the limit means to be deactuated and to cause said motor means to be operated to rotate said door element continuously whilst the switch is operated, without interruption by said limit means.

7. A revolving door as claimed in claim 6 wherein said switch means is arranged to be operated by a detector positioned close to the door and responsive to the presence of a person within the vicinity of the door.

8. A revolving door comprising at least one upright door element arranged in outwardly extending disposition about an upright axis of revolution, motor means being provided together with control means operable to position the door at a first rotational disposition from which, when the door is turned in one direction by a user pushing against said door element, power assistance is given to the door to effect rotation thereof;

limit means being provided to cause the door to then come to rest at said first rotational disposition, in the absence of continued pushing by said user, after movement of the door under action of said motor means, wherein said motor means includes a split-phase induction motor having two windings connected to said control means, said control means, in normal use of the motor, applying out of phase alternating current from the supply to the windings to effect operation of the motor to provide said power assistance;

said limit means including means operable, in use of the door, to apply in-phase alternating currents from said supply to said windings to stop the motor and bring said door to rest at said first rotational disposition, wherein said control means operates to slow said motor prior to application of said in-phase currents and after application of said out of phase currents for a predetermined rotation of the door element, said slowing being effected by applying alternating current from said supply to one said winding and a rectified current to the other said winding, and wherein said control means controls supply of currents to the motor through two cam operated switches thereof, cams associated with the switches being connected to be turned concomitantly with said door element, a first of said switches being actuated upon movement of the door in said one direction away from said first rotational disposition to effect said application of said out of phase currents to said motor windings, this switch being operated via a first of said cams, this being shaped so that said first switch is deactuated at a second disposition of said door element somewhat less than 360°

of rotation of the door element past said first disposition, the said application of said alternating current to said one winding and said rectified current to said other winding being effected under control of the second of said switches operated by a second of said cams, which second cam is shaped to effect operation of said second switch at or shortly after the door element reaches said second disposition during rotation thereof, said second cam being shaped to deactuate said second switch when said first disposition is again reached during said rotation, said limit means being sensitive to deactuation of both said switches after substantially 360°

of rotation of the door element has occurred, to apply said in-phase alternating currents to said windings for a preselected time period after said deactuation.