This application is directed to motors and using multiple power supplies to operate these motors.
Various types of motors can be used to move barriers or for other purposes. In one example, electric motors are used to move barriers such as garage doors, gates, or sliding doors. In another example, such motors are used in sump pump applications. Typically, the motor is connected to an AC power source and the AC voltage from this source is converted to a DC voltage to actually drive the motor. Sometimes, a battery backup is used when power from the mains power supply fails or is otherwise insufficient to operate the motor. In a sump pump application, water level is tracked to determine when to switch to a separate backup motor.
Different approaches have been used through the years that utilize two power sources to operate a DC motor. In one approach, a high voltage motor is selected and this motor is powered directly with the rectified mains AC voltage when the system is not in battery backup mode. When in battery backup mode, a large voltage is needed to power the high voltage motor. To generate the high voltage needed, a large number of batteries (in order to create the high-voltage) may be used. Alternatively, a small, low voltage battery and a switched-mode power supply may be used to convert the low voltage battery into a high-voltage power supply and thereby operate the motor. In either of these approaches, the cost of the system becomes high due to the requirement of large numbers of batteries or the addition of a switched mode power supply, and also the system becomes heavy and bulky with the addition of such components.
Another approach for using two power supplies with a motor utilizes a low voltage DC motor. In this case, a transformer or switched mode power supply is used to create a low voltage from the mains power source to operate the low voltage motor. In battery backup mode, the motor's operating voltage is set to match the battery voltage. However, due to the use of the transformer or switched mode power supply and the additional circuitry required, this approach is also expensive and physically heavy to implement.
Still another previous approach uses two separate motors (in two separate housing units) to move the barrier. One motor is powered directly by the rectified mains voltage source and the other motor is powered by the battery backup. However, using two motors has the disadvantage of the added expense and weight of the second motor.
An apparatus and method to operate a motor in one of at least two modes in response to determining that a power provided by a power supply for the motor crosses certain thresholds. In one example, the apparatus includes first and second windings (or first and second groups of windings) wound to apply a rotating force to a rotating armature (i.e., a rotor) of a single motor (i.e., a motor whose components are encased in a single housing). The first and second windings are electrically coupled to first and second commutators, respectively, which transmit power to the first and second windings from a first power source and a second power source, respectively. More specifically, power from a first power source is selectively applied to the first commutator (and thereby the first winding), and power from a second power source is selectively applied to the second commutator (and thereby the second winding), based on a determination of the power available from one or both power sources. In response to the application of power to the windings, the armature turns, and this movement moves a barrier that is coupled to the motor (for instance, via the central shaft of the motor).
In some aspects, the approaches described herein are accomplished automatically, that is, without the requirement of any manual intervention by a user. For instance, an inadequate mains power may be detected, and in response, the power for the motor may be switched automatically to the battery backup. Because a user is not required to actuate a switch or perform another action, the switchover can occur seamlessly without disruption of supply of power and the resultant halting of the motor. This aspect in one example is implemented using a processing device configured to determine a status of at least one of a first power source or a second power source wherein the processing device is configured to select one of the first power source for application to the first commutator or the second power source for application to the second commutator in response to the status determination. The processing device can communicate with various types of sensors such as voltage sensors, current sensors, power sensors, or sensors that sense the speed of the motor can be used to sense various attributes of the power source.
In other aspects, different power sources power the motor, the motor operates at different speeds depending on the power source applied. For example, in one method, the change in application of power sources is effected in response to detecting a change in applied power past a threshold, thus effecting the motor's operation in a second, different speed. So configured, a single motor and not dual or multiple motors in separate multiple housings can so operate to reduce deployment of bulky and expensive additional equipment (either with the original device or separately provided add on elements) such as extra transformers, switched mode power supplies, or the like.
In one example, a mains power supply provides the first power supply, and a back-up battery device provides the second power supply. The power drives a motor that, in turn, moves a barrier such as a garage door, sliding door, gate, swinging door, shutters, or the like to mention but a few examples. In another application, the motor powers a pump to displace fluid in a sump pump application. In some circumstances, the mains power supply is completely cut-off or lost (or at least the amount of power is reduced to become inadequate to drive the motor to move the barrier) such that a battery back-up power supply is needed to drive the motor to move the barrier. One of the windings of the motor is configured to be powered by the mains power supply when the power from the mains power supply is determined to be adequate. The battery backup powers another winding in response to determining that the power from the mains power supply is inadequate. The switching from driving the motor as between the mains power supply and the battery backup can be accomplished automatically, without the need for a user to intervene or select the power supply to use. The determination as to whether the amount of power is adequate may, for example, involve comparing a sensed or measured power, voltage, speed (in terms of speed of a movable barrier moved by the motor or amount of fluid pumped over time, depending on the application), and/or current supplied by a power source to a threshold amount.
In another example aspect, the motor can be configured to operate at different speeds depending upon the power supply selected. For example, with the mains power supply chosen, the motor is configured to operate at a higher speed as opposed to operating at a lower speed when the battery backup is used. Because it can be desirable to operate the motor at a lower speed when the battery backup is used to reduce load on the battery and because reliance on a battery backup can be an infrequent occurrence, the winding connected to be powered by the battery backup can be designed to use less material, thereby reducing the size, weight, and cost of the winding. For example, the winding connected to be powered by the battery may include copper wire that is smaller in mass than would be required if the battery backup required high speed because the power requirement to move the barrier at a lower speed is reduced. Using one or more of these approaches reduces the size and/or weight of the motor as well as the overall cost of the system. Furthermore, the size and cost of the backup battery can be reduced because the motor requires less power to operate in battery backup mode.
So configured, these teachings support the utilization of a single motor in a single housing, thus avoiding expensive and separate multiple housings. Such a system can also reduce the use of bulky and expensive additional equipment such as extra transformers, switched mode power supplies, or the like. Additionally, these approaches can be accomplished automatically, that is, without the requirement of any manual intervention by a user. Moreover, because the motor can operate at slower speeds in certain configurations, the motor and/or power supply can be further configured to be less bulky, weigh less, and cost less than in previous arrangements.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted to facilitate a less obstructed view of these various embodiments of the present invention. It will further be appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein.
Referring now to
In the example of
The motor 115 configured to effect movement of the movable barrier 20 in response to operation of the motor 115. In this example, the motor 115 includes a rotating armature 124 with a first winding 126 and a second winding 128, each configured to apply a rotating force on the rotating armature 124 in response to receiving power. Coupling of the armature 124 to the barrier 20 may be accomplished by any type of mechanical coupling arrangement such as using gears, shafts, levers, and/or belts to mention a few examples. The barrier 20 itself may be any type of movable barrier such as a garage door, gate, sliding door, swing door, shutters, or the like. Other examples of barriers are possible. In a typical electric motor, permanent magnets (not shown in
The motor 115 further includes a first commutator 120 and a second commutator 122, each being coupled to the rotating armature 124 such that power supplied to the first commutator 120 flows to the first winding 126 and power supplied to the second commutator 122 flows to the second winding 128, either power application being effective to turn the rotating armature 124. In the example of
A processing device 106 configured to determine a status of at least one of a first power source 102 or a second power source 104, wherein without user interaction and based at least upon the status, the processing device 106 is configured to select one of the first power source 102 for application to the first commutator 120 or the second power source 104 for application to the second commutator 122. The selection occurs without user interaction, in other words automatically in response to the determined status without needing a user to provide an additional input to effect the selection. This does not disclaim user input in initially setting up or modifying a general operation configuration of a system. By one approach, the first power source 102 is a mains line voltage or power supply 102, and the second power source 104 is a backup battery. The mains line voltage 102 can be obtained from a wall outlet (for example, having an AC voltage of 120V in the United States). The battery backup 104 can be any type of battery that is used to produce electrical voltage, power, and/or current. One or more individual batteries may be coupled together to form the battery backup 104.
By one approach, the status determined by the processing device 106 is associated with a parameter such as an amount of power, an amount of current, or an amount of voltage available from the first power source 102 and/or the second power source 104. The processing device 106 can do so by receiving one or more signals from a sensor 108. The sensor 108 may be any type of sensor (for example, one or more of voltage sensors, current sensors, or power sensors) that is used to sense various attributes of the power source (for example, one or more of voltage, current, or power). This sensing can be performed by directly sensing of the attribute (for example, a current probing device) or by indirect sensing such as measuring the speed of the motor, which demonstrates a loss of power. In the example of
The processing device 106 can be configured to control power applied to the motor in a variety of ways in response to the determination of the status of one or more of the power supplies 102 and 104. Those skilled in the art will recognize and appreciate that such a processing device 106 can comprise a fixed-purpose hard-wired platform, which could be as simple as an analog threshold circuit, or can comprise a partially or wholly programmable platform. All of these architectural options are well known and understood in the art and require no further description here.
In one approach, in response to determining that the status indicates an amount of power from the main power supply 102 below a threshold amount, the processing device 106 is configured to select the battery power source 104 to use to power the motor 115. In another approach, in response to determining that the status indicates an amount of power from the main power supply 102 above a threshold amount, the processing device 106 is configured to select the mains power supply 102 to use to power the motor 115. The threshold is chosen such that power provided at that threshold is sufficient to open a barrier connected to be moved by the motor 115. Accordingly, the threshold may vary depending on the size and type of barrier to be moved and the configuration of the motor 115. An example threshold to be monitored by the processing device 106 is 120 Volts, when used with a standard one half horsepower motor used for a typical garage door application. In other approaches, it will be appreciated that determinations made by the processing device 106 may be based, upon other factors, sensed values, or other types of information (for instance, sensed readings from other sensors not shown in
In one approach to controlling the coupling of power sources to the motor 115, the processing device 106 can control the application of power through being operatively connected to an electric coupling 110. The electric coupling 110 controls the flow of electrical power, voltage, and current from the mains line voltage 102 and battery backup 104 to a motor 115. The electric coupling 110 may also perform rectification of the AC mains line voltage or other conditioning functions for the mains power supply voltage and/or the backup battery voltage.
Referring now to
Referring now to
In one aspect, referring again to
For example, the windings' 126 and 128 characteristics and/or dimensions can be selected so as to be able to receive and support a particular range of voltage, current, and/or power and in response turn the armature 124 to operate the motor 115 at a particular speed or torque. In this respect, the size (for example, gage), diameter, length, weight, and/or construction material (to mention a few examples) of the wire used to create the windings 126 and 128 can be chosen to provide a particular operating speed or torque for the motor 115 in response to application of particular voltages, currents, and/or powers. The shape, size, and number of turns of the windings 126 and 128 can be similarly designed with the motor performance goals in mind. To take one example, one winding 126 can be designed to operate from a line voltage (165 DC) with a speed of 10,000 RPM while the other winding 128 can be designed to operate from a 12 VDC battery with a speed of 4,000 RPM. As such, the windings 126 and 128 may be configured, dimensioned, and/or constructed differently from each other based upon the power that can be potentially received from a particular power source.
Turning again to
So configured, the motor 115 can be configured to operate at a higher speed when using a primary power source such as a main voltage as opposed to a lower speed when the battery backup 104 is used. Because in many applications the backup power supply is rarely used, it is often acceptable to operate the motor 115 at a lower speed when using the battery backup. Accordingly, a smaller winding 128 can be used for operating motor 115 on a battery backup resulting in using less metal in the motor. For instance, the windings 128 configured to be powered by the battery backup can be smaller, shorter, less thick, and/or weigh less than would be required if a higher speed were desired. This, in turn, reduces the overall size and/or weight of the motor 115 as well as the overall cost of the system. Furthermore, the size and cost of the backup battery 104 can be reduced because the motor 115 requires less energy to operate in battery backup mode.
Referring now to
In another optional portion of the method, the method includes detecting 614 that power from the mains power supply is above the threshold. In response to this detection 614, the method includes effecting 616 electrically coupling the first power source from the first commutator and electrically decoupling a second power source to the second commutator. In this aspect, the system can automatically switch back to powering the motor by a mains power supply from the battery backup in a situation where the mains power is restored. So configured, a user need not adjust the power configuration of the motor when a mains power is lost or restored.
Referring now to
More specifically, the armature 710 includes a first winding 706 and a second winding 708 that can be wound on top of each other but can be disposed at different ends of the armature 710. The first winding 706 is coupled to a first commutator 712 and the second winding 708 is coupled to the second commutator 713. First electrical brush 714 transfers electrical power from first power lines 720 to the first commutator 712 and hence to the first winding 706. Second electrical brush 740 transfers power from second power lines 732 to the second commutator 713 and to the second windings 708. The transfer of power from the power lines is effective to cause the armature 710 to turn and thereby rotate the shaft 718. Rotation of the shaft 718 is effective to move the barrier.
The commutators 712 and 713 in this example are metallic rings configured in two or more segments with gaps between these segments. The brushes 714 and 740 may be any type of motor brush known to those skilled in the art and, in one example, may be carbon contact pads. The power lines 720 and 732 transmit power between the power sources and the motor 700.
The windings 706 and 708 have characteristics and/or dimensions selected so as to be able to receive and support a maximum predetermined voltage, current, and/or power. In this respect, the size (for example, gage), diameter, length, weight, and/or construction material (to mention a few examples) may be chosen to support various voltages, currents, and/or powers. To take one example, a longer winding may be used to support a line voltage of 120 V as compared to supporting a battery backup voltage that is less than 120 V (for example, 12V). As such, the windings 706 and 708 may be configured, dimensioned, and/or constructed differently based upon the power received from a particular power source.
In some aspects, each winding 706 and 708 is coupled to an individual power source. For instance, the winding 706 may be selectively coupled to the mains line voltage, and the winding 708 may be coupled to the battery backup. In other aspects, only one of the windings 706 and 708 is energized at a time; however, in still other aspects it is possible to energize both windings at the same time.
So configured, the motor may be configured to operate at different speeds depending upon the power supply selected. By using a reduced size winding on the same armature as a first winding, the size, weight, and dimensions of the overall motor is reduced. A single motor with two windings eliminates the need for a second motor specifically configured to work as a backup with a backup power supply. By configuring the winding to match the needs of a barrier system in a low power environment, additional power conditioning equipment can be largely eliminated, and battery backup size can be reduced. By configuring the system to automatically switch the application of power supplies based on information from the supplies, a user does not have to manually reconfigure the system after a change in power supply status.
Another application for a dual mode motor as described herein illustrated in
In any event, water level sensors (not shown), which are known in the art, detect the water level 815 in the sump pit 805 and send signals regarding the water level to a controller 825, which is analogous to the processing device and electric coupling described above. Water collects in the sump pit 805 from the inlet 820. If the water level exceeds a certain height, the controller 825 in response to receiving signaling from the water level sensors effects operation of the motor 800 to pump fluid from the sump pit 805 to a drainage area usually located outside of the building.
The controller 825 is connected to receive power from a first power supply, the mains power 830, and from a second power supply, a battery backup 840. As described above, the controller 825 controls which power source provides power to the motor 800 based on the power that is available. In one such example, the motor 800 is configured to operate at a first pumping rate when the mains power supply 830 is electrically coupled to the first commutator and to operate at a second pumping rate when the battery power source 840 is electrically coupled to the second commutator. The first pumping rate is greater than the second speed; in one example, the first pumping rate is at least 40% higher than the second pumping rate. The pumping rate is typically measure in units of volume of fluid over a period of time, for example, 3000 gallons/hour.
In a sump pump application, having a backup power supply readily available is advantageous in the event that mains power is lost in a storm, when flooding is most likely. The dual mode motor 800 described herein is advantageous in this application because many sump pits are small or located in tightly spaced areas. Accordingly, a compact dual mode motor with a compact battery backup is particularly advantageous over bulkier two-motor systems where a second motor is triggered in response to water level.
Those skilled in the art will recognize that a wide variety of modifications, alterations, and combinations can be made with respect to the above described embodiments without departing from the scope of the invention. For instance, more than two winding can be applied to the same armature, wherein the windings are associated with different power supplies. and that such modifications, alterations, and combinations are to be viewed as being within the ambit of the inventive concept.