AU5356800A - Improved door movement control method and device - Google Patents

Description

Our Ref:7522160 P/00/011 Regulation 3:2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT a.

S

Applicant(s): Evans Deakin Pty Ltd 12 Boundary Street South Brisbane Queensland 4101 Australia DAVIES COLLISON CAVE Patent Trade Mark Attorneys Level 10, 10 Barrack Street SYDNEY NSW 2000 Address for Service: Invention Title: Improved door movement control method and device The following statement is a full description of this invention, including the best method of performing it known to me:- 5020 P:\WPDOC\AMD\SPECA7522 160.DOC 22/8/00 -1- IMPROVED DOOR MOVEMENT CONTROL METHOD AND DEVICE BACKGROUND OF THE INVENTION The present invention relates to a method and apparatus for providing improved control over movement of a rolling overhead door, or like door, and in particular, to a method and device for more accurately identifying the position, speed, direction or other movement characteristics of such a door.

DESCRIPTION OF THE PRIOR ART 10 Rolling overhead doors are known to be used on garage openings. Such doors typically include a flexible door curtain which can be raised and lowered from a drum located above the door aperture. Typically, a pair of end drums are rotatably mounted on a fixed axle extending horizontally across the top of the door aperture. The curtain secured at its upper end to each of the spaced end drums, and a ring gear is secured 15 to one drum and provided with a motor drive for rotating the drums and thereby raising and lowering the door.

Door controllers of the type having a remote control transmitter which sends a coded signal to a controller coupled to the door drive means for controlling raising and 20 lowering the door are also well known. These controllers often operate in conjunction with mechanically operated upper and lower limit switches and obstruction detection devices.

More recent developments include devices whereby the controllers 'learn' the characteristics of a particular door. For example, in the Applicant's US Patent No.

4831509 (and corresponding family members) a controller is provided which includes a door position encoder for providing signals indicative of the position of the door curtain relative to the door opening, a timing mechanism for providing timing signals for said controller, a processing mechanism responsive to said encoder and said timing mechanism for producing a representation of a door travel speed characteristics, and, a memory device coupled to said processing mechanism for storing representation of P:\WPDOC9\VAM\SPEC1\75221 60DOC 22/8/00 -2a door travel speed characteristics.

Whilst the aforementioned controllers have their merits, one of the drawbacks is the need to, particularly after a power failure or the like, have the door to 'relearn' the door characteristics prior to being able to be returned to normal door operation. For example, it is necessary to operate such prior art doors between their open and closed positions such that these positions can be restored in memory. They are also prone to operate inaccurately in the event of climatic variations, track condition, etc., resulting in false tripping of the door mechanism.

S Therefore, this identifies a need to provide an improved control mechanism which is not prone to the above disadvantages.

S. SUMMARY OF THE INVENTION S 15 The present invention seeks to provide a device and a method for overcoming the disadvantages of the prior art by providing a device and a method for identifying the position, speed, direction, or other movement characteristics of a door, and for utilising such characteristics to control the movement of the door.

S: 20 In one broad form, the present invention provides a device for identifying a position or movement characteristic of a door, said device including: segment marking means associated with said door, to uniquely represent each of a plurality of segments into which said door is divided; and, sensor means to sense each unique segment marking and provide an output indicative of the position or movement of the said door.

Preferably, said segment marking means is embodied as a plurality of physical markings located along the length of said door, and, said sensor means are positioned adjacent the opening of said door, whereby the relative position or movement of said door relative to said door opening are thereby sensored, or vice versa.

P\WPDOC\AMD\SPEC\7522160.DOC 22/8/00 -3- In this form, preferably, said segment marking means includes a plurality of protrusions extending along the length of said door or said door opening, respectively.

Alternatively, but also preferably, said segment marking means is embodied as a rotatable device, operatively connected to said door, said rotatable device being provided with a plurality of physical markings thereon, and, said sensor means is located on a stationary device cooperatively positioned adjacent said rotatable device, to sense the relative movement of said rotatable device to said stationary device, or vice versa.

l0 In this form, preferably, said rotatable device is connected to said door via one or more gear.

Also, in this form, preferably, said segment marking means includes a plurality of 15 radially spaced arcuate protrusions provided on said rotatable device.

Preferably, said sensor means includes one or more opto electric device, for example, one or more light emitting diode (LED).

S: 20 Also preferably, said position characteristics are determined by correlation of said output with predetermined data pertaining to said door position.

Preferably, the speed, direction, and/or velocity of said door is determined by sensing the speed and/or direction of traversing said segment markings.

Preferably, the speed, direction and/or velocity of said door is determined by sensing the speed and/or direction of traversing teeth or like protrusions not associated with said segment markings.

Also preferably, said teeth are provided on a separate rotatable cutter wheel.

In a further broad form, the present invention provides a method of identifying the P:\WPDOCS\AMD\SPECI\7522160.DOC 228/00 -4position, speed, direction or other movement characteristic of a door, said method including the steps of: providing marking means associated with said door to uniquely identify each of a plurality of segments dividing said door; providing the sensor means to sense the movement of said door relative to said door opening; and, operating the said door and to obtain an output from said sensor means, whereby said output is correlated with prelearned data to provide said position or movement characteristics of said door.

l Preferably, in this method, said marking means are representative of a code, such as a three bit grey code.

Also preferably, said pre-learned data is learned by driving said door and operating S 15 limit set switches or the like.

"Preferably, upon detection of an obstruction, said position or movement characteristics 9 are used to stop and/or control the movement of said door thereafter.

S: 20 Also preferably, following a power interruption, said segment marking means are used to identify the position of said door.

In a further broad form, the present invention provides a device and method for controlling the operation of a door, which utilises the identifying device and method as hereinbefore described.

P:\WPDOCS\AMD\SPECI\52216.DOC -221800 BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the following detailed description of preferred but nonlimiting embodiment thereof, described in connection with the accompanying drawings wherein: Figure 1 illustrates a perspective view of an embodiment for monitoring the movement of a door, in accordance with the present invention; Figure 2 illustrates the opto gear interaction with the printed circuit board opto interrupters for the embodiment of Figure 1; Figure 3 illustrates a plan view of embodiments of the opto gears is in 10 accordance with the invention; Figure 4 illustrates a flowchart of a start-up safe direction algorithm; Figure 5 illustrates a flowchart of a cutter interrupt service routine; and, Figure 6 illustrates a flowchart of a learn limits algorithm.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S) Throughout the drawings, like numerals will be used to identify similar features, except where expressly otherwise indicated.

To accurately control the movement of a door, such as a rolling door, the electronic S 20 circuitry utilises various inputs from the mechanism that drives the rolling door. These *.9 inputs are correlated to provide door position information, such as the upper and lower door limits, and, collision detection information, to reverse the door if it collides while closing, or halt the door if it jams when opening. Three inputs are used in the present invention, namely, information from a Position Gear, a Cutter Gear, and, from a Motor Current Sensor (not described here) In Figure 1, is shown a ring gear 1, which is attachable to a drum of a rolling overhead door by passing an axle through the axle support 2. Figure 1 shows the operative connection of a position gear 3 and a cutter gear 4 to the ring gear 1 via a follower 5, an opto drive 6, and an idler gear 7. As such, when engaged, the position gear 3 and the cutter gear 4 rotate in the cooperation with ring gear 1, such that their P:\WPDOCS\AMD\SPECI\7522160.DOC -22/8100 -6movement is representative of the movement of the door. The position, speed, direction, and/or other movement characteristics of the position gear 3 and the cutter gear 4 are therefore able to the sensed by opto interrupters 8 9, respectively.

A plan view of the position gear 3 and the cutter gear 4 are shown in Figure 3. As can be seen in Figure 3, the position gear 3 is provided with arcuate projections 10, 11, and 12 of varying radius. It will be understood that in the provision of the arcuate projections at selected locations will enable a unique 'code' to be identified by each of the opto interrupters when sensing the presence or absence to the projections 10, 11, 10 and 12 as the position gear 3 rotates. Typically, a three bit grey code may be :established by appropriate positioning of the arcuate projections.

In Figures 1 to 3, the three-bit gray coded position gear is driven by the ring-gear 1 with a reduction ratio of 0.29:1.0. This allows 7/8ths of one position gear 3 revolution to be 15 unambiguously decoded during the opening of a large door (three ring gear revolutions).

The output of the three-bit encoder is available to the processor controlling the door operation. The drive for the encoder from the ring gear 1 is independent of the clutch, so absolute positional information is retained during movement with the clutch disengaged. The only way to change the relationship between the position gear 3 and the 20 door location is to disengage the ring gear from the door drum.

The information provided from the position gear 3 may, as mentioned, use a gray code form, to prevent ambiguity at transfix. To convert this number into a sequential sector number, a look up table is used based on the left/right orientation in relation to the door.

The sector number is a modulo 8 value which increases as the door moves downwards independent of the door opener mounting. During the learning of limits, the processor will store the exact position of each gray code transition with output to the highresolution cutter gear 4 hereinafter described. The position gear 3 is able to be used to re-align the cutter gear 4 after a power outage.

To accurately determine the position and velocity of the door, a 34 tooth bi-phasic cutter gear 4 is driven from the ring-gear 1, independent of the clutch mechanism. The teeth P:\WPDOCS\AMD\SPEC7522160D0C 22/8/00 -7of this gear 4 pass through a pair of opto electric devices, such as LEDs and appropriate sensors, such that upon rotation a pulse train is provided to the processor. The "tooth velocity" may typically be 1 tooth per millimetre of door travel. Using a quadrature encoder algorithm, both speed and directional displacement may therefore be derived from the cutter gear 4 and its related sensor devices. This positional count from the cutter gear 4 is realigned on each edge transition of the position gear as described in Figure The derived speed output is used to detect door stall, independent of the motor current.

This enables the system to identify conditions, such as operation with the clutch disengaged. In this instance, the motor current will not show an overload but the door S 10 velocity will remain at zero. The door opener will therefore halt, showing an error.

Without this feature, the door opener motor would run for 30 seconds before timing out and stopping.

When the door opener is initially installed the open and closed limits must initially be set, 15 such that the desired region of movement is established. As such, a learn procedure is initially required to be undertaken. This can be done manually by moving the door to each extreme position and manually activating limit set switches.

When not reset or learning limits, the door controller will be in one of the following 20 states: State Description Open Door stationary at upper limit Opening Door driving upwards Paused Opening Door stationary after pause while moving upwards Closed Door stationary at lower limit Closing Door driving upwards Paused Closing Door stationary after pause while moving downwards P:\WPDOCS\AMD\SPECI\7522160.DOC -22/8/00 -8- The door then moves according to the following rules: Current State Action Next Action Open Operate Closing Autoclose Closing Opening Operate Paused Opening Upper Limit Open Collision Halted with error Paused Opening Operate Closing Closed Operate Opening Closing Operate Paused Closing Lower Limit Closed Collision Opening Paused Closing Operate Opening A typical sequence of movement is; Closed (Press operate) Opening (Reached upper limit) Open Open (Press operate) -o Closing (Reached lower limit) Closed If the operate button is repeatedly pressed while the door is moving, it will following this sequence: Opening Paused Opening Closing Paused Closing Opening If a mains power interruption occurs, then a restart procedure, such as shown in Figure 4 must be followed. When power to the door opener has been interrupted, the exact door position is lost as this is not stored in EEPROM. There is no reason to store the door P:\WPDOES\AMD\SPECI\7522160.DOC 2218/00 -9position, as while the power was off, the clutch may have been disengaged and the door moved. Therefore any stored information may be erroneous. When power is re-applied, the firmware uses the position gear 3 opto interrupters 8 to get an approximation for the door position. If the door is in the lower region of travel (ie: lower sectors), the door will move upward on the next activation. If the door is in the upper region of travel then it will move down on next activation. This is deemed the safe operating direction, and is most likely to produce the operator's expectation of movement as the door is usually left either fully open or fully closed. This also allows the largest travel before collision with a physical limit. This ensures that the door will travel through a sector boundary before the 10 actual limit is reached. When movement next crosses an absolute position encoder sector .oo.

boundary, the position monitoring circuit will be realigned from the sector transition table stored in EEPROM. Once the position counter has been realigned, door movement will perform as per normal operation.

15 The combination of cutter and position encoders, mean that a door with correctly set limits will never collide with its travel end-points, irrespective of power outage or clutch S use. From a users perspective they will not be aware that the power has been interrupted -and may manually open the door at any time without affecting the doors operation.

S 20 It should be noted that until the position counter has been realigned, the door will not travel (in the unsafe direction) beyond the power-up position. For example if the door was nearly closed then the door cannot be fully closed until it has moved passed a sector transition boundary. This mode of operation will be very rarely, if ever, observed.

It should also be noted that if the door has been moved more than approximately 50 cm outside the previously learned limits, then when the power is restored the limits will not be reset. This is a fail-sale mode that prevents the software from making an erroneous assumption about door position. Subsequently when operate is pressed the Limit Set LED will flash to indicates an unknown limit condition. To rectify either manually move the door back within the programmed limits range or re-program limits.

P:\WPDOCS\AMD\SPEC\7522160.DOC 228/00 Whilst a particular embodiment of a position gear has been hereinbefore described, it will be appreciated that the positioning of the arcuate projections 10, 11 and 12 may be varied to conform to other 'codes'. Also, it will be appreciated that rather than providing arcuate projections on a rotatable position gear 3, that similar projections, or alternative means, may be provided on the door opening, on the door itself, or otherwise.

In the embodiment described, the position gear 3 is utilised to monitor the position only of the door, and the cutter gear 4 is used to monitor the speed and direction only of the door movement. It will be appreciated by persons skilled in the art, that the position gear 3 and the cutter gear 4 may be effectively combined into one rotatable device whereby the opto interrupters may additionally determine speed and direction, and/or, further opto interrupters may be provided on only one rotatable device to monitor such speed, direction, velocity, or other movement characteristics.

Use of a three-bit gray code as described in the preferred embodiments provides eight S"unique sectors of movement. The largest of doors it typically designed to only need to travel through seven of these sectors, noting that the start and finish sectors are not significant as the code effectively wraps around. However, other codings and other S: 20 numbers of bits may be used depending upon the particular door and the desirability to have more or less door movement monitoring and control.

P:\WPDOCSkAMD\SPECI\7522160.DOC 22/8/00 11 It will also be appreciated that whilst certain flowcharts are shown that numerous variations and modifications may be enacted to the particular algorithms to operation and control the movement of the door.

All such variations and modifications which become apparent to persons skilled in the art should be considered to fall within scope of the invention as broadly hereinbefore described and as hereinafter claimed.

o

Claims (14)

1. A device for identifying a position or movement characteristic of a door, said device including: segment marking means associated with said door, to uniquely represent each of a plurality of segments into which said door is divided; and, sensor means to sense each unique segment marking and provide an output indicative of the position or movement of the said door.

2. A device as claimed in claim 1, wherein said segment marking means is 10 embodied as a plurality of physical markings located along the length of said door, and, said sensor means are positioned adjacent the opening of said door, whereby the relative position or movement of said door relative to said door opening are thereby sensored, or vice versa. 9

3. A device as claimed in claim 1, wherein said segment marking means is embodied as a rotatable device, operatively connected to said door, said rotatable device being provided with a plurality of physical markings thereon, and, said sensor means is located on a stationary device positioned adjacent said rotatable device, to s sense the relative movement of said rotatable device to said stationary device, or vice versa.

4. A device as claimed in claim 3, wherein said rotatable device is connected to said door via one or more gear.

5. A device as claimed in claim 2, wherein said segment marking means includes a plurality of protrusions extending along the length of said door or said door opening, respectively. P:\WPDOCS\AMD\SPECI\7522160.DOC 22/8/00 13

6. A device as claimed in any one of claims 1 to 4, wherein said segment marking means includes a plurality of radially spaced arcuate protrusions provided on said rotatable device.

7. A device as claimed in any one of claims 1 to 6, wherein said sensor means includes one or more opto electric device, for example, one or more light emitting diode (LED).

8. A device as claimed in any one of claims 1 to 7, wherein said position characteristics are determined by correlation of said output with predetermined data pertaining to said door position. A device as claimed in any one of claims 1 to 8, wherein the speed, direction, and/or velocity of said door is determined by sensing the speed and/or direction of traversing said segment markings. A device as claimed in any one of claims 1 to 8, wherein the speed, direction Poe and/or velocity of said door is determined by sensing the speed and/or direction of traversing teeth or like protrusions not associated with said segment markings. 9 9

11. A device as claimed in claim 10, wherein said teeth are provided on a separate rotatable cutter wheel.

12. A method of identifying the position, speed, direction or other movement characteristic of a door, said method including the steps of: providing marking means associated with said door to uniquely identify each of a plurality of segments dividing said door; providing the sensor means to sense the movement of said door relative to said door opening; and, operating the said door and to obtain an output from said sensor means, whereby said output is correlated with prelearned data to provide said position or P:\WPDOCS\AMD\SPECR7522160DOC 22/8/00 -14- movement characteristics of said door.

13. A method of identifying the position or movement characteristics of the door as claimed in claim 12, wherein said marking means are representative of a code, such as a three bit grey code.

14. A method as claimed in claim 12 or 13, wherein said pre-learned data is learned by driving said door and operating limit set switches or the like. S 10 15. A method as claimed in any one of claims 12 to 14, wherein, upon detection of an obstruction, said position or movement characteristics are used to stop and/or control the movement of said door thereafter. 0 S

16. A method as claimed in any one of claims 12 to 15, wherein, following a power interruption, said segment marking means are used to identify the position of said door.

17. A device for identifying a position or movement characteristic of a door, substantially as herein described with reference to the accompanying drawings. 5 0 S 20 18. A method of identifying the position, speed, direction or other movement characteristic of a door, substantially as herein described. DATED this 22nd day of August, 2000 EVANS DEAKIN PTY LIMITED By Its Patent Attorneys DAVIES COLLISON CAVE