Patent Publication Number: US-2004040674-A1

Title: System and method for controlling a motorized window covering

Description:
RELATED APPLICATIONS  
     [0001] The present invention is a Continuation-in-Part of U.S. patent application Ser. No. 10/062,921 filed on Feb. 1, 2002. 
    
    
     
       FIELD OF THE INVENTION  
       [0002] The present invention relates generally to window covering peripherals and more particularly to remotely-controlled window covering actuators.  
       BACKGROUND OF THE INVENTION  
       [0003] Window coverings that can be opened and closed are used in a vast number of business buildings and dwellings. Examples of such coverings include horizontal blinds, vertical blinds, pleated shades, roll-up shades, and cellular shades made by, e.g., Spring Industries, Hunter-Douglas, and Levellor.  
       [0004] The present assignee has provided several systems for either lowering or raising a window covering, or for moving the slats of a window covering between open and closed positions. Such systems are disclosed in U.S. Pat. Nos. 6,189,592, 5,495,153, and 5,907,227, incorporated herein by reference. These systems include a motor driven gear box that is coupled to a tilt rod of the window covering. When the motor is energized, the tilt rod rotates clockwise or counterclockwise. These systems can, e.g., include actuators that are mechanically coupled to the window coverings and operated via a remote control unit. As recognized herein, with a relatively wide remote control signal, if two or more actuators are placed in close proximity to each other, e.g., in the situation where two or more windows are side by side and each includes a remote signal receiver, it can be very difficult to control a single actuator with the remote control unit. In other words, a user may be unable to direct the signal beam at just one receiver.  
       [0005] As a result, the present invention recognizes a need for a system that will allow control of a single motorized window covering within an array of motorized window coverings.  
       SUMMARY OF THE INVENTION  
       [0006] A system for controlling a motorized window covering includes an actuator that is mechanically coupled to an operator of the window covering. A remote control unit selectively communicates with the actuator. A visible light beam emitter and an encoded light beam emitter are installed within the remote control unit. The visible light beam emits a blinking visible light beam.  
       [0007] In a preferred embodiment, the encoded light beam emitter emits an encoded light beam that is superimposed on the blinking visible light beam. Preferably, the blinking visible light beam is similar in size and shape to the encoded light beam. Also, the encoded light beam is coaxial, or approximately coaxial, with the blinking visible light beam. In a preferred embodiment, the blinking visible light beam blinks at a rate of approximately between two and four pulses per second, inclusive. Moreover, each pulse of the visible light beam has a duty cycle of between approximately twenty percent and fifty percent, inclusive.  
       [0008] In another aspect of the present invention, a remote control unit for controlling a motorized window covering includes a visible light beam emitter and an encoded light beam emitter housed with the visible light beam emitter. In this aspect, the visible light beam emitter emits a blinking visible light beam that aids a user in directing the light from the encoded emitter.  
       [0009] In yet another aspect of the present invention, a method for controlling a motorized window covering with a remote control unit includes providing a blinking visible light beam and an encoded light beam superimposed over the blinking visible light beam. The encoded light beam carries control data. In this aspect, the blinking visible light beam is used to direct the encoded light beam.  
       [0010] In still another aspect of the present invention, a remote control unit for controlling a motorized window covering includes means for emitting a blinking visible light beam and means for emitting an encoded light beam.  
       [0011] The details of the present invention, both as to its construction and operation, can best be understood in reference to the accompanying drawings, in which like numerals refer to like parts, and which: 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0012]FIG. 1 is a perspective view of a window covering actuator of the present invention, shown in one intended environment, with portions of the head rail cut away for clarity;  
     [0013]FIG. 2 is a perspective view of the gear assembly of the actuator of the present invention, with portions broken away;  
     [0014]FIG. 3A is a perspective view of the main reduction gear of the actuator of the present invention;  
     [0015]FIG. 3B is a cross-sectional view of the main reduction gear of the actuator of the present invention, as seen along the line  3 B- 3 B in FIG. 3A;  
     [0016]FIG. 4 is a side plan view of a remote control unit emitting a control signal beam directed at an array of actuators; and  
     [0017]FIG. 5 is a cross-section view of the control signal beam. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0018] Referring initially to FIG. 1, an actuator is shown, generally designated  10 . As shown, the actuator  10  is in operable engagement with a rotatable tilt rod  12  of a window covering, such as but not limited to a horizontal blind  14  having a plurality of louvered slats  16 . As shown, the tilt rod  12  is rotatably mounted by means of a block  18  in a head rail  20  of the blind  14 .  
     [0019] In the embodiment shown, the blind  14  is mounted on a window frame  22  to cover a window  24 , and the tilt rod  12  is rotatable about its longitudinal axis. The tilt rod  12  engages a baton (not shown), and when the tilt rod  12  is rotated about its longitudinal axis, the baton (not shown) rotates about its longitudinal axis and each of the slats  16  is caused to rotate about its respective longitudinal axis to move the blind  14  between an open configuration, wherein a light passageway is established between each pair of adjacent slats, and a closed configuration, wherein no light passageways are established between adjacent slats.  
     [0020] While the embodiment described above discusses a horizontal blind, it is to be understood that the principles of the present invention apply to a wide range of window coverings including, but not limited to the following: vertical blinds, fold-up pleated shades, roll-up shades, cellular shades, skylight covers, and any type of blinds that utilize vertical or horizontal louvered slats.  
     [0021] A control signal generator, preferably a daylight sensor  28  is mounted within the actuator  10  by means well-known in the art, e.g., solvent bonding. In accordance with the present invention, the daylight sensor  28  is in light communication with a light hole  30  through the back of the head rail  20 , shown in phantom in FIG. 1. Also, the sensor  28  is electrically connected to electronic components within the actuator  10  to send a control signal to the components, as more fully disclosed below. Consequently, with the arrangement shown, the daylight sensor  28  can detect light that propagates through the window  24 , independent of whether the blind  14  is in the open configuration or the closed configuration.  
     [0022] Further, the actuator  10  can include another control signal generator, preferably a signal sensor  32 , for receiving a preferably optical user command signal. Preferably, the user command signal is generated by a hand-held user command signal generator  34 , which can be an infrared (IR) remote-control unit. In one presently preferred embodiment, the generator  34  generates a pulsed signal.  
     [0023] Like the daylight sensor  28 , the signal sensor  32  is electrically connected to electronic components within the actuator  10 . As discussed in greater detail below, either one of the daylight sensor  28  and signal sensor  32  can generate an electrical control signal to activate the actuator  10  and thereby cause the blind  14  to move toward the open or closed configuration, as appropriate.  
     [0024] Preferably, both the daylight sensor  28  and signal sensor  32  are light detectors which have low dark currents, to conserve power when the actuator  10  is deactivated. More particularly, the sensors  28 ,  32  have dark currents equal to or less than about 10 −8  amperes and preferably equal to or less than about 2×10 −9  amperes.  
     [0025] As shown in FIG. 1, a power supply  36  is mounted within the head rail  20 . In the preferred embodiment, the power supply  36  includes four or six or other number of type AA direct current (dc) alkaline or Lithium batteries  38 ,  40 ,  42 ,  44 . Or, the batteries can be nine volt transistor batteries. The batteries  38 ,  40 ,  42 ,  44  are mounted in the head rail  20  in electrical series with each other by means well-known in the art. For example, in the embodiment shown, two pairs of the batteries  38 ,  40 ,  42 ,  44  are positioned between respective positive and negative metal clips  46  to hold the batteries  38 ,  40 ,  42 ,  44  within the head rail  20  and to establish an electrical path between the batteries  38 ,  40 ,  42 ,  44  and their respective clips.  
     [0026]FIG. 1 further shows that an electronic circuit board  48  is positioned in the head rail  20  beneath the batteries  38 ,  40 ,  42 ,  44 . It can be appreciated that the circuit board  48  can be fastened to the head rail  20 , e.g., by screws (not shown) or other well-known method and the batteries can be mounted on the circuit board  48 . It is to be understood that an electrical path is established between the battery clips  46  and the electronic circuit board  48 . Consequently, the batteries  38 ,  40 ,  42 ,  44  are electrically connected to the electronic circuit board  48 . Further, it is to be appreciated that the electronic circuit board  48  may include a microprocessor.  
     [0027] Still referring to FIG. 1, a lightweight metal or molded plastic gear box  50  is mounted preferably on the circuit board  48 . The gear box  50  can be formed with a channel  51  sized and shaped for receiving the tilt rod  12  therein. As can be appreciated in reference to FIG. 1, the tilt rod  12  has a hexagonally-shaped transverse cross-section, and the tilt rod  12  is slidably engageable with the gear box opening  51 . Accordingly, the actuator  10  can be slidably engaged with the tilt rod  12  substantially anywhere along the length of the tilt rod  12 .  
     [0028]FIG. 1 also shows that a small, lightweight electric motor  52  is attached to the gear box  50 , preferably by bolting the motor  52  to the gear box  50 . As more fully disclosed in reference to FIG. 2 below, the gear box  50  holds a gear assembly which causes the tilt rod  12  to rotate at a fraction of the angular velocity of the motor  52 . Preferably, the motor  52  can be energized by the power supply  36  through the electronic circuitry of the circuit board  48  and can be mounted on the circuit board  48 .  
     [0029] Also, in a non-limiting embodiment, a manually manipulable operating switch  54  can be electrically connected to the circuit board  48 . The switch  54  shown in FIG. 1 is a two-position on/off power switch used to turn the power supply on and off. Further, a three-position mode switch  56  is electrically connected to the circuit board  48 . The switch  56  has an “off” position, wherein the daylight sensor  28  is not enabled, a “day open” position, wherein the blind  14  will be opened by the actuator  10  in response to daylight impinging on the sensor  28 , and a “day shut” position, wherein the blind  14  will be shut by the actuator  10  in response to daylight impinging on the sensor  28 .  
     [0030]FIG. 1 further shows that in another non-limiting embodiment, a manually manipulable adjuster  58  can be rotatably mounted on the circuit board  48  by means of a bracket  60 . The periphery of the adjuster  58  extends beyond the head rail  20 , so that a person can turn the adjuster  58 .  
     [0031] As intended by the present invention, the adjuster  58  can have a metal strip  62  attached thereto, and the strip  62  on the adjuster  58  can contact a metal tongue  64  which is mounted on the tilt rod  12  when the tilt rod  12  has rotated in the open direction.  
     [0032] When the strip  62  contacts the tongue  64 , electrical contact is made therebetween to signal an electrical circuit on the circuit board  48  to de-energize the motor  52 . Accordingly, the adjuster  58  can be rotationally positioned as appropriate such that the strip  62  contacts the tongue  64  at a predetermined angular position of the tilt rod  12 . Stated differently, the tilt rod  12  has a closed position, wherein the blind  14  is fully closed, and an open position, wherein the blind  14  is open, and the open position is selectively established by manipulating the adjuster  58 .  
     [0033] Now referring to FIGS. 2, 3A, and  3 B, the details of the gear box  50  can be seen. As shown best in FIG. 2, the gear box  50  includes a plurality of lightweight metal or molded plastic gears, i.e., a gear assembly, and each gear can be rotatably mounted within the gear box  50 . In the presently preferred embodiment, the gear box  50  is a clamshell structure which includes a first half  65  and a second half  66 , and the halves  65 ,  66  of the gear box  50  are snappingly engageable together by means well-known in the art. For example, in the embodiment shown, a post  67  in the second half  66  of the gear box  50  engages a hole  68  in the first half  65  of the gear box  50  in an interference fit to hold the halves  65 ,  66  together.  
     [0034] Each half  62 ,  64  includes a respective opening  70 ,  72 , and the openings  70 ,  72  of the gear box  50  are coaxial with the gear box channel  51  (FIG. 1) for slidably receiving the tilt rod  12  therethrough.  
     [0035] As shown in FIG. 2, a motor gear  74  is connected to the rotor  76  of the motor  60 . In turn, the motor gear  74  is engaged with a first reduction gear  78 , and the first reduction gear  78  is engaged with a second reduction gear  80 . In turn, the second reduction gear  80  is engaged with a main reduction gear  82 . To closely receive the hexagonally-shaped tilt rod  12 , the main reduction gear  82  has a hexagonally-shaped channel  84 . As intended by the present invention, the channel  84  of the main reduction gear  82  is coaxial with the openings  70 ,  72  (and, thus, with the gear box channel  51  shown in FIG. 1).  
     [0036] It can be appreciated in reference to FIG. 2 that when the main reduction gear  82  is rotated, and the tilt rod  12  is engaged with the channel  84  of the main reduction gear  82 , the sides of the channel  84  contact the tilt rod  12  to prevent rotational relative motion between the tilt rod  12  and the main reduction gear  82 . Further, the reduction gears  78 ,  80 ,  82  cause the tilt rod  12  to rotate at a fraction of the angular velocity of the motor  60 . Preferably, the reduction gears  78 ,  80 ,  82  reduce the angular velocity of the motor  60  such that the tilt rod  12  rotates at about one revolution per second. It can be appreciated that greater or fewer gears than shown can be used.  
     [0037] It is to be understood that the channel  84  of the main reduction gear  82  can have other shapes suitable for conforming to the shape of the particular tilt rod being used. For example, for a tilt rod (not shown) having a circular transverse cross-sectional shapes, the channel  84  will have a circular cross-section. In such an embodiment, a set screw (not shown) is threadably engaged with the main reduction gear  82  for extending into the channel  84  to abut the tilt rod and hold the tilt rod stationary within the channel  84 . In other words, the gears  74 ,  78 ,  80 ,  82  described above establish a coupling which operably engages the motor  60  with the tilt rod  12 .  
     [0038] In continued cross-reference to FIGS. 2, 3A, and  3 B, the main reduction gear  82  is formed on a hollow shaft  86 , and the shaft  86  is closely received within the opening  70  of the first half  62  of the gear box  50  for rotatable motion therein. Also, in a non-limiting embodiment, a first travel limit reduction gear  88  is formed on the shaft  86  of the main reduction gear  82 . The first travel limit reduction gear  88  is engaged with a second travel limit reduction gear  90 , and the second travel limit reduction gear  90  is in turn engaged with a third travel limit reduction gear  92 .  
     [0039]FIG. 2 best shows that the third travel limit reduction gear  92  is engaged with a linear rack gear  94 . Thus, the main reduction gear  82  is coupled to the rack gear  94  through the travel limit reduction gears  88 ,  90 ,  92 , and the rotational speed (i.e., angular velocity) of the main reduction gear  82  is reduced through the first, second, and third travel limit reduction gears  88 ,  90 ,  92 . Also, the rotational motion of the main reduction gear  82  is translated into linear motion by the operation of the third travel limit reduction gear  92  and rack gear  94 .  
     [0040]FIG. 2 also shows that in non-limiting embodiments, the second reduction gear  80  and second and third travel limit reduction gears  90 ,  92  can be rotatably engaged with respective metal post axles  80   a ,  90   a ,  92   a  which are anchored in the first half  65  of the gear box  50 . In contrast, the first reduction gear  78  is rotatably engaged with a metal post axle  78   a  which is anchored in the second half  66  of the gear box  50 .  
     [0041] Still referring to FIG. 2, the rack gear  94  can be slidably engaged with a groove  96  that is formed in the first half  65  of the gear box  50 . First and second travel limiters  98 ,  100  can be connected to the rack gear  94 . In the non-limiting embodiment shown, the travel limiters  98 ,  100  are threaded, and are threadably engaged with the rack gear  94 . Alternatively, travel limiters (not shown) having smooth surfaces may be slidably engaged with the rack gear  94  in an interference fit therewith, and may be manually moved relative to the rack gear  94 .  
     [0042] As yet another alternative, travel limiters (not shown) may be provided which are formed with respective detents (not shown). In such an embodiment, the rack gear is formed with a channel having a series of openings for receiving the detents, and the travel limiters can be manipulated to engage their detents with a preselected pair of the openings in the rack gear channel. In any case, it will be appreciated that the position of the travel limiters of the present invention relative to the rack gear  94  may be manually adjusted.  
     [0043]FIG. 2 shows that in one non-limiting embodiment, each travel limiter  98 ,  100  has a respective abutment surface  102 ,  104 . As shown, the abutment surfaces  102 ,  104  can contact a switch  106  which is mounted on a base  107 . The base  107  is in turn anchored on the second half  66  of the gear box  50 . As intended by the present invention, the switch  106  includes electrically conductive first and second spring arms  108 ,  112  and an electrically conductive center arm  110 . As shown, one end of each spring arm  108 ,  112  is attached to the base  107 , and the opposite ends of the spring arms  108 ,  112  can move relative to the base  107 . As also shown, one end of the center arm  110  is attached to the base  107 .  
     [0044] When the main reduction gear  82  has rotated sufficiently counterclockwise, the abutment surface  102  of the first travel limiter  98  contacts the first spring arm  108  of the switch  106  to urge the first spring arm  108  against the stationary center arm  110  of the switch  106 . On the other hand, when the main reduction gear  82  has rotated clockwise a sufficient amount, the abutment surface  104  of the second travel limiter  100  contacts the second spring arm  112  of the switch  106  to urge the second spring arm  112  against the stationary center arm  110  of the switch  106 .  
     [0045] It can be appreciated in reference to FIG. 2 that the switch  106  can be electrically connected to the circuit board  52  (FIG. 1) via an electrical lead  119 . Moreover, the first spring arm  108  can be urged against the center arm  110  to complete one branch of the electrical circuit on the circuit board  48 . On the other hand, the second spring arm  112  can be urged against the center arm  110  to complete another branch of the electrical circuit on the circuit board  48 .  
     [0046] The completion of either one of the electrical circuits discussed above causes the motor  52  to de-energize and consequently stops the rotation of the main reduction gear  82  and, hence, the rotation the tilt rod  12 . Stated differently, the travel limiters  98 ,  100  may be manually adjusted relative to the rack gear  94  as appropriate for limiting the rotation of the tilt rod  12  by the actuator  10 .  
     [0047] Referring briefly back to FIG. 2, spacers  120 ,  122  may be molded onto the halves  62 ,  64  for structural stability when the halves  62 ,  64  of the gear box  56  are snapped together.  
     [0048] Referring now to FIG. 4, details of the remote control unit  34  are shown. FIG. 4 shows that the remote control unit  34  includes a visible light beam emitter  200  and an invisible, e.g., IR, encoded light beam emitter  202 . It is to be understood that in lieu of an invisible light beam emitter  202  an RF transmitter or other means of communication can be used. As shown, the visible light beam emitter  200  emits a relatively narrow visible light beam  204  that is visible when it strikes an object. Moreover, the encoded light beam emitter  202  emits an encoded light beam  206  that preferably is substantially the same size and shape as the visible light beam  204 . It is to be understood that the encoded light beam  206  carries the actuator control data.  
     [0049] In a preferred embodiment, the encoded light beam  206  is superimposed on the visible light beam  204  such that the light beams  204 ,  206  are more or less coaxial. A low power laser or a focused high intensity light emitting diode (LED) in the visible light range are preferred for use as the visible light beam emitter  202 . In a less preferred embodiment, an incandescent bulb can be used.  
     [0050] According to present principles, if the visible light beam emitter  202  is a visible LED or an incandescent bulb, the intensity of the visible light beam  204  can be limited by the visible light beam emitter  202  or the power available thereto. In either case, the visible light beam  204  can be difficult to observe at distances consistent with the range of the encoded light beam  206  especially in areas of high ambient light. To overcome this limitation, the visible light beam  204  preferably is blinked at a rate fast enough to allow the operator to continuously know the location of the encoded light beam  206 . It can be appreciated that the duration of the ON time must be longer than retinal response to assure that the blinking visible light beam  204  is not integrated by the eye. In a preferred embodiment, the blinking visible light beam  204  blinks at a rate approximately between two and four pulses per second, inclusive. Also, in a preferred embodiment, the duration of the ON time is at a duty cycle of between approximately twenty percent and fifty percent, inclusive. If desired, each pulse may last no more than approximately eighty three and three-tenths milliseconds (83.3 ms), providing a duty cycle of approximately twenty five percent (25%). This duty cycle allows the instantaneous output power of the visible light beam emitter  202  to be increased fourfold, which effectively doubles the range of the visible light beam  204  for any given conditions of the ambient light.  
     [0051] It is to be understood that for shorter operating distances or for operation in low levels of ambient light, the function of pointing and controlling can be combined, e.g., in the light beam of a single emitter. It can be appreciated that for distances greater than fifty feet, a higher powered laser can be used for the visible light beam emitter  202 . However, it can be appreciated that if the visible light beam  204  is produced by a laser, it is important to minimize its power for both regulatory and safety concerns. If the visible light beam is a laser, the encoded light beam may be broader than the visible light beam, but should be as narrow as practicable for optimum selectivity.  
     [0052]FIG. 4 shows that the light beams  204 ,  206  can be directed at an array of actuators  208 . The array of actuators  208  include a first actuator  210 , a second actuator  212 , and a third actuator  214 . Each actuator  210 ,  212 ,  214  is identical to the actuator  10  described above. It can be appreciated that more or less than three actuators can be used.  
     [0053] Referring to FIG. 5, it is shown that the first actuator  210  includes a first signal sensor  216  and the second actuator  212  includes a second signal sensor  218 . FIG. 5 shows the light beams  204 ,  206  striking the first actuator  210 . As shown, the visible light beam  204  aids a user in pointing the remote control  34  so that the encoded light beam  206  is precisely directed at one of the signal sensors  216 ,  218 , e.g., the first signal sensor  216  as shown. Thus, a user is able to individually control the actuators  210 ,  212 ,  214 . It is to be understood that the configuration described above, e.g., the visible/invisible signal configuration, can be used in any remote-control unit where ambiguity might arise at the receiver.  
     [0054] While the particular SYSTEM AND METHOD FOR CONTROLLING A MOTORIZED WINDOW COVERING as herein shown and described in detail is fully capable of attaining the above-described aspects of the invention, it is to be understood that it is the presently preferred embodiment of the present invention and thus, is representative of the subject matter which is broadly contemplated by the present invention, that the scope of the present invention fully encompasses other embodiments which may become obvious to those skilled in the art, and that the scope of the present invention is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.” All structural and functional equivalents to the elements of the above-described preferred embodiment that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the present claims. Moreover, it is not necessary for a device or method to address each and every problem sought to be solved by the present invention, for it is to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. section 112, sixth paragraph, unless the element is expressly recited using the phrase “means for.”