AU2009201063A1 - Door operator circuit board - Google Patents

Description

AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION Standard Patent Applicant (a): Smart Openers Pty Ltd Invention Title: DOOR OPERATOR CIRCUIT BOARD The following statement is a full description of this invention, including the best method for performing it known to me/us: P80513.AU PatSelFiling Applicatlon 2009-3-17.doc (M) -2 DOOR OPERATOR CIRCUIT BOARD This invention relates to a door operator circuit board and relates particularly but not exclusively to a 5 door operator circuit board for use in domestic garage door installations. Hitherto, it has been known to provide door operator circuit boards in door operators for use in domestic io garage doors. It has also been known to provide circuit boards in door operators for semi industrial doors, industrial doors, swing gates and sliding gates. The invention herein is applicable to all such door/gate operators. 15 In the known art, it is typical to provide a D.C. motor for driving the door or gate between open and closed positions. D.C. motors draw considerable current in order to effect switching ON of the motor. Thus is necessary to 20 provide switching relays. Because of the large current, the size of the switching relays is such that considerable footprint space is occupied by the switching relays on the circuit board. This, in turn, makes the overall footprint of the circuit board extremely large. Switching relays 25 used in the prior art door operator circuit boards have not enjoyed a lengthy lifespan owing to the high switching currents. This, in turn, required repeated service for replacement of the switching relays. 30 Generally, it is desired to have a physically small footprint circuit board to minimise the overall size of a door operator housing that carries the circuit board. It is also desired to have improved switching so as to minimise any service needed consequent on anticipated 35 failure of the known switching relays. Therefore, in accordance with a first broad aspect of N.Melboume\Cases\Patent\8OOO-80999\P80469.AU\Specis\PB0513 AU Specification 2009-3-11 doc 17103/09 -3 the present invention there is provided a door or gate operator circuit board, said circuit board comprising a processor module, a D.C. motor control module, and an interface module to 5 permit a user to initiate operation of a D.C. motor used for opening and closing a door, said D.C. motor control module comprising a solid state switch for effecting a D.C. polarity reversal to the D.C. motor for controlling direction of rotation of the 10 D.C. motor, said polarity reversal being operatively controllable through said processor module in response to user input commands initiated by a user through said interface module. 15 In one example of the invention, the switch comprises four discreet solid state switches configured in an 'H' bridge circuit with said D.C. motor connected in the central arm of said bridge circuit, a first switch thereof 20 being in an upper upright first leg, a second switch thereof being in a lower upright first leg, a third switch thereof being in an upper upright second leg, and a fourth switch thereof being in a lower upright second leg, and wherein D.C. motor voltage of one plurality is applied to 25 the first and third switches and D.C. motor voltage of opposite polarity to the second and fourth switches, and wherein said 'H' bridge circuit is made conductive through said first switch and said fourth switch to selectively switch said D.C. motor to rotate in 30 one direction, and wherein said 'H' bridge circuit is made conductive through said third switch and said second switch to selectively switch said D.C. motor to rotate in the opposite direction, each of the selective switching being under control from said processor module. 35 In one example, said switch is driven by a driver device in response to instruction controlled from said N:Melboume\Cases\Patent\8OOO-80999\PB0469 AU\Specis\P80513.AU Specification 2009-3-11 .doc 17/03/09 -4 processor module. In one example, said driver device comprises a respective driver device for each of the first through 5 fourth switches, and wherein each driver device connects with an associated first through fourth switch via a respective resistor device of impedance in the range 0 15 ohms. 10 In one example, said solid state switch is a MOSFET switch. In order that the invention can be more clearly ascertained, examples of embodiments of the invention will is now be described with reference to the accompanying drawings wherein: Figure 1 shows a schematic block circuit diagram of a door operator circuit board, 20 Figure 2 is a schematic circuit diagram of a solid state switch, Figure 3 is a block schematic circuit diagram in 25 overview form of the examples shown in Figures 1 and 2, Figure 4 is a block schematic diagram of an alternative example, 30 Figure 5 is a functional flow diagram showing a "soft start" mode, Figure 6 is a block schematic diagram of an example of a door operator circuit board where a shaft encoder is 35 used to determine the position of the door or gate. Figure 7 is a functional flow diagram showing a "end N:\Melboume\Cases\Patent\8000-80999\P80469.AU\Specis\P80513.AU Specification 2009-3-11.doc 17/03/09 -5 stop position mode", in one example, and Figure 8 is an example of a graph showing an example of how a speed of door profile can be adjusted to suit the s speed of movement of the end of the door (or gate). Referring firstly to the examples of Figures 1 - 3, it can be seen that a 24 volt D.C. motor 1 is provided to drive a door between open and closed positions. Other 10 voltage D.C. motors are possible and are not excluded. A door operator circuit board 3 is provided to contain the main operating control circuit components of the door operator device. The door operator device can comprise dedicated components for domestic, semi industrial or 15 industrial doors, or gates as described previously. In addition, the circuit board 3 may be configured for different types of doors. Roller doors are one example, tilt doors are another example and sectional doors are another. In addition, gates may be swing gates or sliding 20 gates and there may be one or two gates involved. Typically therefore, the door operator circuit board 3 is configured with the necessary components for the particular environment. 25 Figure 1 shows the necessary components for explaining operation of the example of the present invention. Other components as are known in the art for controlling operation of the door or gate have been omitted for clarity. In Figure 1, there is shown a 30 processor module 5 that typically comprises a suitable microprocessor with resident firmware for operation of the D.C. motor to suit the door or gate involved. The overall firmware per se does not form a part of certain concepts herein and will accordingly not be described in detail. 35 The circuit board 3 also contains a D.C. motor control module 7. The circuit board 3 also contains a user interface 9 which will allow a user to interact with the N:\Melboume\Cases\Patent\80000-80999\P80469.AU\Specis\P80513.AU Specification 2009-3-11 .dc 17/03109 -6 processor module 5 to permit manual instruction to the D.C. motor controller module 7 to permit the motor 1 to open and close the door or gate. The user interface module 9 may contain user operable input means such as 5 push buttons. It may also include input means such as push buttons to effect entry of control parameters to the processor module 5 such as setting speed of travel of the door or gate, final open and closed stop positions of the door or gate, duration of ON time of any courtesy lights 10 that may be activated in response to operation of the motor 1 and other known features associated with door or gate operators. The user interface module 9 may include a receiver device (not shown) to permit wireless remote control of the door or gate from a hand held transmitter is device operated by a user. Figure 3 schematically shows an arrangement for use with the door operator circuit board 3 shown in Figure 1. Here, D.C. power is supplied to a solid state switch and 20 pulse width modulation (pwm) circuit 11, comprising part of the D.C. motor control module 7. A microprocessor 13 that forms part of the processor module 5 controls operation of the motor 1 according to the firmware resident with the microprocessor 13. 25 In operation, a user provides command signals through the interface module 9 to open and close the door or gate and/or to stop the travel of the door or gate. The solid state switch and pulse width modulating circuit 11, in 30 turn, provides or disconnects D.C. power to the D.C. electric motor 1 for these purposes. Typically, the solid state switch and pulse width modulating circuit 11 applies voltage at a correct polarity to the D.C. motor 1 to permit rotation in a clockwise or anticlockwise direction. 35 This reversal is achieved by a polarity reversal of the voltage to the D.C. motor 1. The pulse width modulation provides for a speed control of the D.C. electric motor 1 N:\elboume\Cases\Patent\80000-80999\P80469.AU\Specis\P80513.AU Specification 2009-3-11.doc 17/03/09 -7 in response to control signals initiated by the microprocessor 13. Accordingly, if the door is to be opened, then the user inputs an open command which in turn, causes the microprocessor 13 to instruct the solid s state switch and pulse width modulation circuit 11 to apply the required polarity voltage to the D.C. electric motor 1. For operation in the opposite direction, a polarity reversal of the voltage applied to the D.C. electric motor 1 is made through the solid state switch 10 and pulse width modulation circuit 11. The microprocessor 13 can, in turn, provide pulse width modulation signals to the solid state switch and pulse width modulation circuit 11 to provide required duty cycles in the power supplied from the D.C. power to the D.C. electric motor 1. The 15 duty cycle may change throughout the path of travel of the door or gate such that at extreme end positions the door or gate will travel slowly relative to intermediate positions. 20 Figure 2 shows an example of one possible arrangement of the D.C. motor control module 7. Here, the solid state switch used for effecting a D.C. polarity reversal to the D.C. motor for controlling direction of the rotation of the D.C. motor is shown using four MOSFET devices. 25 Suitable MOSFET devices are manufactured by International rectifier, 233 Kansas Street, El Segundo, California 90245, USA and sold under Model No. IRFP3206PBF. These MOSFET devices have a D.C. current carrying capacity of up to 100 amps. Whilst other solid state switch devices may 30 be used, the particular MOSFET devices indicated above have been found to be suitable. The invention is not to be limited to MOSFET devices per se or to MOSFET devices of the type outlined. In the circuit showing Figure 2, the solid state switches (MOSFETS) are identified as M1, 35 M2, M3 and M4. These devices are arranged in a 'H' bridge circuit with the D.C. motor 1 connected in the central arm of the bridge circuit. A first switch M1 is in an upper N:\Melboume\Cases\Patent\BOO-800 999\P80469 AU\Specis\P80513.AU Specification 2009-3-11.doc 17/03/09 -8 upright first leg, a second switch M2 is in a lower upright first leg, a third switch M3 is in an upper upright second leg, and a fourth switch M4 is in a lower upright second leg. It can be seen that the D.C. motor 5 voltage of one polarity is applied to the first and third switches Ml and M3, and D.C. motor voltage of the opposite polarity applied to the second and fourth switches M2 and M4. The 'H' bridge circuit is made conductive through the first switch Ml and the fourth switch M4 to selectively 10 switch the D.C. motor 1 to rotate in one direction. The 'H' bridge is made conductive through the third switch M3 and the second switch M2 to selectively switch the D.C. motor 1 to rotate in the opposite direction. Each of the selective switching possibilities are under control from is the processor module 5 using logic for this purpose, which is self evident and additional to any of the basic functionality of a door operator processor. Thus, each of the switches Ml, M2, M3, M4 comprise a solid state switch in total. It can be seen from Figure 2 that the switch is 20 driven by a driver device which comprises respective individual driver circuits Dl, D2, D3 and D4. These drivers Dl, D2, D3 and D4 operate in response to instruction control from the processor module 5. The driver devices Dl, D2, D3 and D4 selectively open and/or 25 close gates of the MOSFET switches Ml, M2, M3 and M4. Accordingly, it can be seen that each of the switches in the switch are driven by respective driver devices. It can also be seen that each of the driver devices Dl, D2, D3 and D4 connects with the associated switch through 30 respective resistors Rl, R2, R3 and R4. The resistors Rl, R2, R3, and R4 are provided to shape the open and closing condition of the MOSFET switches Ml, M2, M3 and M4. Manufacturers of the MOSFET devices recommend that the resistors R1, R2, R3, and R4 be approximately 25 ohms. We 35 have discovered that for the inductive loading and transient D.C. current imparted to the D.C. electric motor 1 used for opening and closing doors or gates, that the N:\Melboume\Cases\Patent\80 0 9\P80469.AU\Specis\P80513.AU Specification 2009-3-11 doc 17/03/09 -9 driver devices D1, D2, D3 and D4 overheat and self destruct. We have determined that the resistors R1, R2, R3 and R4 should have an impedance in the range 0 ohms 15 ohms to inhibit against overheating and self 5 destruction of the driver devices Dl, D2, D3, and D4. Returning to the circuit board 3 shown in Figure 1, it should be appreciated that the use of a solid state switch in the D.C. motor control module 7 minimises any 10 footprint space that would otherwise be taken by relays of the required current carrying capacity. In practice the physical space is about 25% - 40% less than that associated with use of relay switch devices. Accordingly, significant savings in footprint space are available 15 which, in turn, means that the physical area of the circuit board module 3 can be smaller than for similar circuit boards 3 that use relay switches. For the case where a circuit board 3 is for use with double motor installations such as in dual swing gates or dual sliding 20 gates, the physical footprint size of the circuit board 3 can be considerably reduced. Thus, a first difference contributes significantly to the working and operation of the circuit board 3 by minimising the physical space required. This enables a more compact and less obtrusive 25 housing of the door operator. Secondly, it should also be appreciated, that solid state switches are inherently more reliable and have a greater length of service than relay switches. Hence, 30 there is a further difference that significantly contributes to the working of the invention. Thirdly, it can be appreciated from viewing Figure 3 and then viewing Figure 2, that the solid state switch 35 comprising MOSFET switches Ml, M2, M3 and M4 avoids the use of additional driving circuit components coupled with large physical size relay switches. Here, the MOSFET N:\MelboureCases\Patent\80000-8999\P80469.AU\Specis\P80513.AU Specification 2009-3-11.doc 17/03/09 - 10 switches Ml, M2, M3 and M4 can be switched with the required polarity configuration for supplying D.C. power and voltage to the D.C. electric motor 1 and these switches are also used for switching the pulse width s modulation power for speed control of the D.C. electric motor 1. In the prior art there is used a switch relay for switching the polarity of the provided D.C. power, and additional pulse width modulation components for pulse width modulating that supplied power. Thus, the pulse 10 width modulation components represent additional driving circuit components to the switch. Hence, in this example, there is a further difference that significantly contributes to the working of the invention over the known prior art by the use of a single solid state switch is device. Figure 4 shows a variation of the circuit configuration that is possible using the teachings of the present invention. Here, a solid state switch such as a 20 MOSFET device may be used to switch the polarity of the D.C. power. This may be under control from the microprocessor. The correct polarised D.C. power can then be provided to a solid state pulse width modulation circuit which then pulse width modulates the electric 25 power to the D.C. electric motor 1. The solid state pulse width modulation circuit may comprise MOSFET devices under control from the microprocessor 13. This example is also included within the scope of the present invention. 30 Whilst it is proposed that the circuit board 3 contain discreet circuits for the processor modules 5, D.C. motor control module 7, and interface module 9, it should be appreciated that each one those modules may be individual modules that plug into the circuit board 3. 35 They need not be made as a single circuit board 3 containing discreet circuits for each of the respective modules as an integral unit. In this case, there may be N:Melboume\Cases\Patent\8000-80999\P80469.AU\Specis\P80513.AU Specfication 2009-3-1 .doc 17/03/09 - 11 plug and socket connections of known type to permit connection of the individual modules to the circuit board 3. 5 It should be appreciated that the firmware in the processor module may have a feature to always start the motor at low speed for an initial period. This may be referred to as a "soft start". Thus, when it is necessary to set open and closed stop positions for the door or gate 10 by entering a "set and stop positions" mode, the motor can be activated to drive the door or gate to the open or closed positions. When the door or gate approaches those positions the user can stop the drive of the motor by activating an appropriate stop control. The motor can 15 then be restarted in the same direction at slow speed i.e. soft start for an initial period. The door or gate can then be repeatedly stopped and started to "inch" the door or gate to the required stop positions. In this way, accurate setting of the set stop positions can be made in 20 contrast to some known arrangements where the door is moved at full speed to the end stop positions during the end stop position setting. The pulse width modulation speed control permits the above function to be performed by controlling the duty cycle of the power supplied to the 25 motor. By always starting the door with a soft start at a slow speed, means that impulse loading caused by rapid inertia load changes can be minimised. This, in turn, increases life expectances of bearings and the like within the motor drive train of the operator, and within the door 30 or gate mountings. This provides a further difference over the known art and significantly contributes to the working of the invention. The soft start may be implemented for all stop and starts no matter where the door or gate is positioned, or at selective positions. 35 Referring now to Figure 5, there is shown an example of a soft start functionality embedded within firmware N:\Melboume\CasesiPatent\80000-8099P806.AU\Specis\P80513.AU Specification 2009-3-11 .doc 17/03109 - 12 within the processor module 5. Here, a start motor command is initiated and the processor implements a routine to soft start. Under this condition, the motor will start at slow speed and gradually build to a 5 particular required speed for the position of door travel. This contrasts with known operator systems where the motor starts at a high speed, or at a particular speed consequent on the position of the door. The slow or soft start mode can be arranged through adjustment of the duty 10 cycle of the pulse width modulation signals provided to the switch. A transmission link 17 is provided between the output drive of the motor 1 and the tilt door 15. The details of this have not been shown as this is known in the art. The tilt door 15, in turn, carries a door 15 position sensing means 19 which may be a magnetically operated or other operated shaft encoder device. Whilst this is shown connected with the tilt door 15, it may be connected either with the motor 1 or anywhere in the transmission link 17. Magnetic pulses are provided from 20 the position sensor 19 which are fed back to the processor module 5 so that the position of the door 15 can be determined. The processor module, in turn, has a program embedded therein to control operation of the door 15. Whilst the door 15 has been shown in the form of a tilt 25 door, it may be any other type of door such as a sectional door, roller door, or gate. Referring now to Figure 7 there is shown a functional flow diagram of operation steps when it is required to set 30 end stop position limits for the operator. Here, it can be seen that a user enters a set end stop limit mode by operating for example particular control buttons. This in turn, starts the motor in either a clockwise or anticlockwise direction. The motor then starts with a 35 soft start. As the door approaches a required end position, the stop motor command is entered. The motor is then started again in the same direction with a soft N \Melboume\Cases\Patent\80000-80999\P80469.AU\Specis\P80513.AU Specification 2009-3-11 .doc 17/03/09 - 13 start. The user then can stop the door again as it progresses further towards the required end stop position whilst in a soft start mode. Eventually, a position can be reached after a plurality of soft starts where the 5 motor is stopped at a required end stop position. The door stop position can be then set such as by operating an appropriate button. The user can then exit the set end stop limit mode, and/or continue for setting the other end stop position. The system repeats its functionality 10 rotating the motor in the opposite direction so that the other end stop position can be set. Referring now to Figure 8, there is shown a graph representing distance of travel of the door or gate and is the speed of motion of the door or gate. The graph shown represents a typical speed of door for a tilt type door 15 shown in Figure 6. Here it can be seen, that the door starts with a soft start from a closed position towards a fully opened position and then builds speed. The end of 20 the door however swings very rapidly at a particular point of travel due to the hinging arrangement of the tilt type door 15. This is represented by the high peak shown in the solid line curve. As the door passes the hinge position which causes the end of the door to travel at a 25 fast speed, the speed then resumes to a normal speed as it approaches the fully opened position. The dotted line curve on Figure 8 shows how the speed of the end of travel of the door can be tailored to have a different profile by using pulse width modulation processes. In this case, a 30 plot can be made of the desired curve and appropriate duty cycles of the pulse width modulation circuit arranged to provide for the required speed of travel of the end of the door 15. Whilst Figure 8 shows the profile for an opening movement of the door, there may be a different profile 35 required for the closing of the door which need not necessary be a mirror image of the opening profile. Accordingly, the processor module 5 can be arranged to N:\Melboume\Cases\Patent\80000-80999\P80469.AU\Specis\P80513.AU Specfication 2009-3-11 doc 17103/09 - 14 provide pulse width modulation signals to control the closing operation of the door. These may be the same a mirror image of the profile for the opening of the door or may be of a different profile. The above arrangement is 5 particularly suitable for tilt type doors 15 known as "J" type tilt doors where there is quick travel in a particular region of the door movement due to the hinge arrangement. The feature can also be incorporated in swing gates to control the speed of movement throughout 10 the speed of travel profile of the swing gate. Modifications may be made without departing from the ambit of the invention the nature of which is to be determined from the foregoing description. 15 In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as 20 "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. 25 In the claims which follow and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to 30 specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. N:\Melboume\Cases\Patent\80000-80999\P80469 AU\Specis\P80513 AU Specification 2009-3-11.doc 17/03109

Claims (10)

1. A door or gate operator circuit board, said circuit board comprising a processor module, a s D.C. motor control module, and an interface module to permit a user to initiate operation of a D.C. motor used for opening and closing a door, said D.C. motor control module comprising a solid state switch for effecting a D.C. polarity reversal to the 10 D.C. motor for controlling direction of rotation of the D.C. motor, said polarity reversal being operatively controllable through said processor module in response to user input commands initiated by a user through said interface 15 module.

2. A door or gate operator circuit board as claimed in claim 1, wherein said switch comprises four discreet solid state switches configured in an 'H' bridge circuit with 20 said D.C. motor connected in the central arm of said bridge circuit, a first switch thereof being in an upper upright first leg, a second switch thereof being in a lower upright first leg, a third switch thereof being in an upper upright second leg, and a fourth switch thereof 25 being in a lower upright second leg, and wherein D.C. motor voltage of one plurality is applied to the first and third switches and D.C. motor voltage of opposite polarity to the second and fourth switches, and wherein said 'H' bridge circuit is made 30 conductive through said first switch and said fourth switch to selectively switch said D.C. motor to rotate in one direction, and wherein said 'H' bridge circuit is made conductive through said third switch and said second switch to selectively switch said D.C. motor to rotate in 35 the opposite direction, each of the selective switching being under control from said processor module. N:Melboume\Cases\Paten\OO-80 99\P80469.AU\Specis\P80513.AU Specification 2009-3-11 .doc 17/03/09 - 16

3. A door or gate operator circuit board as claimed in claim 1 or claim 2, wherein said switch is drivable by a driver device in response to instruction control from said processor module. 5

4. A door or gate operator circuit board as claimed in any one of the preceding claims wherein said driver device comprises a respective driver device for each of the first through fourth switches, and wherein each driver device 10 connects with an associated first through fourth switch via a respective resistor device of impedance in the range zero to 15 ohms.

5. A door or gate operator as claimed in any one of the is preceding claims, wherein said processor module is configured to provide pulse width modulation drive control signals for pulse width modulation speed and rotational direction of said D.C. motor. 20

6. A door or gate operator as claimed in any one of the preceding claims, wherein said solid state switch is a MOSFET switch.

7. A door or gate operator as claimed in any one of the 25 preceding claims, comprising a routine under control from said processor module to start the motor with a soft start.

8. A door or gate operator as claimed in claim 7, 30 comprising a routine under control from said processor module in a set end stop position mode to start the motor with a soft start so there can be inching of movement of the door or gate to a required end stop position at a low speed of movement of travel so there can be fine control 35 of the end stop position.

9. A door or gate operator as claimed in claim 8, N:\Melboume\Cases\Patent\60000-80999\PB0469.AU\Specis\P80513.AU Specification 2009-3-11 doc 17/03109 - 17 comprising a shaft encoder for providing pulse signals representative of the position of the door or gate, so a particular count value of the shaft encoder can be set to represent a position for end stopping the door or gate. 5

10. A door or gate operator as claimed in any one of claims 5 to 9 when dependent on claim 5, comprising an end of door or gate speed profile setting component whereby a duty cycle of said pulse width modulating drive control 10 can be tailored to provide a required speed profile. N:\Melboume\Cases\Patent80000-80999\P80469.AU\Specis\P80513.AU Specification 2009-3-1 I.doc 17/03/09