GB2486918A

GB2486918A - Door closure unit

Info

Publication number: GB2486918A
Application number: GB1022129.9A
Authority: GB
Inventors: Gordon Matthew Condie
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-12-31
Filing date: 2010-12-31
Publication date: 2012-07-04
Also published as: GB2486971A; GB201022129D0; GB2486971B; GB201121880D0

Abstract

The unit 1 comprises a chassis 7 arranged to be supported by the floor, a drive spindle rotatably mounted on the chassis and supported by the chassis, the drive spindle 9 being arranged to engage with and support a door for rotation of the door about the axis of rotation of the spindle 9. An electric motor 16 is provided and a first pulley wheel or cog 20 is coaxially arranged with the spindle 9 and engaged with the spindle. A second pulley wheel or cog (17 figure 1) is connected to the motor and at least one drive belt 18,19 is provided for connecting the motor 16 to the first pulley 20 so that operation of the motor 9 causes the first pulley 20 to rotate with the spindle 9.

Description

Door Actuator Unit The present invention relates to a floor mounted door actuator unit for a swing door.

Floor mounted door actuator unit typically comprise a casing to be embedded in the floor with a top plate to be mounted flush to the surface of the floor. A drive spindle protrudes through the top plate to which a door is directly mounted, about which the door pivots and on which the weight of the door is supported. The actuator units are normally relatively robust, for they directly support the weight of the door, which may be quite considerable in the case of a relatively large plate glass door of the type commonly used as an entrance door in commercial buildings. In addition to being able to support the weight of the door, the actuator unit also has to be strong enough to keep the door closed in adverse weather conditions and! or to prevent unauthorised access.

One example of a floor mounted door closure unit is manufactured by Gretsch-Unitas Limited. This comprises a housing within which an electric motor, mounted in one end of the housing, drives a hydraulic unit. The hydraulic unit has a number of adjustments for controlling the position of the door. The hydraulic unit has an output drive shaft that extends through both sides of a casing of the hydraulic unit. The shaft engages with an input shaft of a gear box, which input shaft similarly extends to both sides of the casing of the gearbox. In this way the gearbox may be mounted in the door closure unit housing to either side of the hydraulic unit, depending on whether door closure unit is a left-hand or right-hand unit. The gearbox has a vertical output shaft, which is the spindle upon which the door is mounted and which carries the weight of the door.

Door closure units of the above type perform very well but are relatively expensive to manufacture, comprising a separate hydrostatic unit and gearbox including a relatively large number of machined parts. The footprints of such units are also relatively wide to the gearbox being mounted to one side of the hydrostatic unit.

According to the present invention there is provided an actuator unit for a swing door operating system, the unit comprising: a chassis arranged to be supported by the floor; a drive spindle rotatably mounted on the chassis and supported by the chassis, the drive spindle being arranged to engage with and support a door for rotation of the door about the axis of rotation of the spindle; an electric motor; a first pulley coaxially arranged with the spindle and engaged with the spindle; a second pulley connected to the motor and at least one drive belt for connecting the motor to the first pulley so that operation of the motor causes the first pulley to rotate with the spindle.

Employing the present invention avoids the need to have a gearbox supporting the weight of the door. Instead the door is supported by the spindle which in turn is supported by the chassis. Rotation of the spindle, and thus the position of the door, is then controlled by the pulley and drive belt arrangement. The number of components can thus be significantly less than in an arrangement employing a gearbox and some of the components, such as the pulleys, may be injection moulded, reducing the number of machined parts that may otherwise be required.

Preferably, the unit further comprises third and fourth pulleys of different diameters arranged coaxially and engaged with each other, the unit comprising a first belt connecting the second and third pulleys and a second belt connecting the third and first pulleys, such that said arrangement of pulleys reduces the drive ratio between the motor and the spindle, the motor, pulleys and spindle being linearly arranged with the motor at a first end of the unit and the spindle and first pulley at the second end of the unit opposite the first end.

The above arrangement reduces the output drive of the gearbox by using a plurality of pulleys and drive belts, but permits these to be arranged in a linear arrangement such that the overall width of the casing can be kept to a minimum with the spindle located towards one end of the housing.

Such a unit may be mounted perpendicular to the door when the door is in the closed position such that it lies along the skirting of a passageway leading to the door. The relatively narrow width of the unit means the unit does not protrude into the walkway area.

Alternatively, the unit may be aligned with the door when the door is in the closed position, thus extending across the walkway. In this arrangement the, the relatively narrow width of the unit means that a significant part of the top plate of the unit is concealed by the width of the door, when the door is in the closed position.

It is advantageous, where the housing is elongate, if the spindle is no more than 65mm from an end of the housing. This permits the housing to be mounted across a doorway with the spindle mounted 65mm from the doorframe, (which is an industry standard), without the unit extending below the doorframe, or into the doorframe where the doorframe extends below the level of the floor.

It is also advantageous that the spindle is no more than 65mm from either side of the housing, enabling the housing to be mounted perpendicular to the doorway, possibly along the skirting of the passageway leading to the doorway. It is advantageous if the housing is rectangular and its length is at least 2.5 times greater than its width. It is also advantageous if the housing is less than 130mm wide.

Advantageously, the spindle is mounted on the chassis by a conical bearing which enables all the weight of the door on the spindle to be supported by the rollers of the bearing.

Preferably, the unit comprises a spiral or helical spring wound around an axis of one pulley and arranged to return a door attached to the spindle to a closed position, wherein the motor is arranged to drive the door against the spring to an open position. This arrangement permits the door to be retumed to the closed position by the spring. This is advantageous because it enables the door to be returned to the closed position in the case of a power failure and it may also be a mechanism for closing the door if it is not desired to operate the motor in the reverse direction to close the door. Preferably the unit can operate as a left-handed or right-handed unit by only modifying the control electronics for the motor and by reversing or replacing the spring.

Advantageously the, or each, belt is a toothed belt and the, or each, pulley is a toothed cog, which avoids possible slippage and wear of the belts.

Preferably, the unit comprises an elongate housing having a base plate to be secured in the floor, wherein the base plate and chassis are ananged such that the chassis can be fixed to the base plate in different positions in the longitudinal direction of the housing.

This enables the housing to first be mounted in the floor and then the exact position of the spindle to be subsequently adjusted.

One embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, of which: Figure 1 is a perspective view of a door closure unit in accordance with the present invention with the cover plate removed; Figure 2 is a plan view of the unit of Figure 1 with the cover plate removed; and Figure 3 is a cross section along the line 111-111 of Figure 2.

Referring to Figures 1 to 3, a door closure unit 1 indicated generally as 1 comprising a housing 2 and a cover plate 3. The housing 2 is arranged to be secured in the floor by means of fastenings 4, seen in Figures 2 and 3. Alternatively, or in addition to the fastenings 4, the housing 2 may be concreted into the floor.

Located in the bottom of the housing 2 is a base plate 5 having a number of slotted apertures 6 therein through which the base plate 5 is bolted to the housing 2. The slotted apertures 6 enable base plate 5 to be moved longitudinally forwards or backwards relative to the housing 2.

Welded to the base plate 5 is a relatively thick steel chassis plate 7 towards one end of which is mounted a conical bearing 8. The conical bearing 8 supports a spindle 9. The spindle 9 comprises a main spindle shaft 9a and an adaptor 9b. The adaptor 9b may be selected from a range of adaptors depending on the fitting present in a door (not shown) to be mounted on the spindle 9 and the clearance desired between the door and the floor.

Alternatively, the main spindle shaft 9a could extend through the cover plate 3 and engage directly with the door.

Also bolted to the chassis plate 7 is a C-shaped steel member 10 having a top plate lOa and a bottom plate lob. The top plate lOa carries bearing 11 maintaining the top of the spindle 9 in position. It also carries bearing 12 vertically aligned with bearing 13 mounted in the bottom plate lOb of C-shaped member 10. Bearings 12 and 13 carry shaft 14 on which teethed cogs l5a and lSb are secured for rotation therewith. Also attached to the chassis plate 7 is a motor 16 which, via toothed cog 17 (see Figure 1) drives first toothed belt 18 which via cogs ISa and 15b drives second toothed belt 19. The second toothed belt 19 drives toothed cog 20 fixed to spindle 9.

Below the toothed cog 20 is mounted a helical spring 21 upon coil spring carrier 22.

First end of the spring 21 engages in aperture 23 of bottom plate lOb. The other end of the spring 21 engages with the cog 20 and the spring 21 is pre-biased such that it returns the cog 20 to its starting position, corresponding to the door being in the closed position when mounted on the spindle 9.

In use, the unit I is mounted in the floor with spindle in the correct position to align with the corresponding engagement point of a door, normally 65mm in from the doorframe.

The unit 1 is mounted such that the top surface of the cover plate is flush with the surface of the floor.

In use, standard control electronics, not illustrated, detects that the door is to be opened, either by a switch being depressed, or an electronic sensor detecting movements in the vicinity of the door, whereupon the control electronics actuates the motor 16. The motor 16, typically a 24 volt DC motor such as the ML 10 made by Label SpA, drives the spindle 9 via drive belts 18 and 19 and associated cogs iSa, 15b, against the spring 20 opening a door connected to the spindle 9. When the door reaches its fully opened position, the control circuitry detects this and stops the motor 16 with the back EMF of the motor preventing the spring 20 returning the door to its closed position.

When it is desired to close the door, or in the event of power failure, the motor 16 is switched so that no back EMF is present and the spring 20 drives the motor 16 in the opposite direction until the door is closed. Alternatively, the control circuitry can be energised to drive the motor 16 in the opposite direction at a predetermined rate until it is detected that the door has reached its closed position.

The unit 1 has a maximum width of 130mm with the spindle centrally located such that it is not only 65mm from the end or either side of the housing 2 to the unit 1. This enables the unit 1 to either be mounted across the threshold of the doorway or along the edge of a skirting leading along the passage leading to the doorway.

The unit 1 may either function as a left-handed or right-handed unit 1 by selection of appropriate drive circuitry for the motor and by fitting either a spring 20 wound in a clockwise direction, or alternatively a spring wound anti-clockwise if the unit 1 is to function as a right-handed unit 1.

One embodiment of the present invention has been described by way of example of only and a skilled person will realise that many modifications are possible to this design which modifications fall within the scope of the appended claims.

Claims

Claims 1. A floor mounted door actuator unit for a swing door, the unit comprising: a chassis arranged to be supported by the floor; a drive spindle rotatably mounted on the chassis and supported by the chassis, the drive spindle being arranged to engage with and support a door for rotation of the door about the axis of rotation of the spindle; an electric motor; a first pulley coaxially arranged with the spindle and engaged with the spindle; a second pulley connected to the motor and at least one drive belt for connecting the motor to the first pulley so that operation of the motor causes the first pulley to rotate with the spindle.
2. A unit as claimed in Claim 1, comprising: third and fourth pulleys of different diameters ananged coaxially and engaged with each other, the unit comprising a first belt connecting the second and third pulleys and a second belt connecting the third and first pulleys, such that said anangement of pulleys reduces the drive ratio between the motor and the spindle, the motor, pulleys and spindle being linearly arranged with the motor at the first end of the unit and the spindle and first pulley at the second end of the unit opposite the first end.
3. A unit as claimed in Claim 1 or 2, where the spindle is mounted on the chassis by a conical bearing.
4. A unit as claimed in any preceding claim, further comprising a spiral or helical spring wound around the axis of one pulley and arranged to return a door attached to the spindle to a closed position, wherein the motor is arranged to drive the door against the spring to an open position.
5. A unit as claimed in Claim 4, which can operate as a left handed or right handed unit by only modifying the control electronic for the motor and by reversing or replacing the spring.
6. A unit as claimed in any preceding claim, wherein the or each belt is a toothed belt and the or each pulley is a toothed cog.
7. A unit as claimed in any preceding claim, comprising an elongate housing comprising a base plate to be secured to the floor, wherein the base plate and chassis are arranged that the chassis can be fixed to the base plate in different positions in the longitudinal direction of the housing.
8. A unit as claimed in any preceding claim, comprising an elongate housing, wherein the spindle is no more than 65mm from an end of the housing.
9. A unit as claimed in Claim 7 or 8, wherein the spindle is no more than 65mm from either side of the housing.
10. A unit as claimed in Claim 7, 8 or 9, wherein the housing is rectangular and is at least 2.5 times greater than its width.
11. A unit as claimed in any one of Claims 7 to 10, wherein the housing is less than 160mm wide.
12. A unit as claimed in any one of Claims 7 to 11, wherein the housing is waterproof
13. A door operating system comprising a unit as claimed in any preceding claim, supporting a swing door mounted on the spindle.
14. An actuator unit for a swing door operating system, substantially as hereinbefore described, and/or as illustrated with reference to one or more of the accompanying figures.