Patent Abstract:
The present invention provides a control apparatus for automatic sliding doors that can be used with a plurality of door brands and models. The invention includes a control box and an idler pulley mounted to the door header. Both the control box and idler pulley can be mounted on a variety of door models by means of specific header brackets that are configured for each door model. The control box also provides a universal signal interface that can interpret sensor signals from a plurality of door models. A drive belt revolves on the idler pulley and is moved by a motorized pulley controlled by the control box. At least one belt bracket is fastened to the drive belt with a belt clamp, wherein the belt bracket is attached to a sliding door panel. Like the control box and idler pulley, the belt bracket can be used with a variety of door models and is attached to the sliding panel by means of a door bracket that is specific to the door model in question.

Full Description:
BACKGROUND OF THE INVENTION 
   1. Technical Field 
   The present invention relates generally to automatic pedestrian sliding doors, and more specifically to a control and drive mechanism that can be retrofitted to existing automatic pedestrian doors. 
   2. Description of Related Art 
   Automatic pedestrian sliding doors are commonplace in many shopping centers, office buildings, hospitals, airports and the like. Motors and control mechanisms mounted in the doorframes control the movement of the doors, usually in combination with motion sensors or pressure pads in the floor that detect people and objects approaching the doors. 
   Typically, the motor/control mechanisms are specific to the door brand and model, which reduces user flexibility in upgrading to newer technologies. To update the control mechanism, the customer is required to replace the entire door assembly or the exact replacement part that is defective or malfunctioning. The costs of this all or nothing approach include not only cost of the complete door assembly itself or the location of exact replacement parts (which might no longer be in production) but also remodeling and the necessary inconvenience and disruption to business that goes along with such major renovations. 
   Therefore, it would be desirable to have an automatic door control mechanism that can be retrofitted to automatic doors already installed and in service, independent of door brand or model and incorporating updated control technology. 
   SUMMARY OF THE INVENTION 
   The present invention provides a control apparatus for automatic sliding doors that can be used with a plurality of door brands and models. The invention includes a control box and an idler pulley mounted to the door header. Both the control box and idler pulley can be mounted on a variety of door models by means of specific header brackets that are configured for each door model. The control box also provides a universal signal interface that can interpret sensor signals from a plurality of door models. A drive belt revolves on the idler pulley and is moved by a motorized pulley controlled by the control box. At least one belt bracket is fastened to the drive belt with a belt clamp, wherein the belt bracket is attached to a sliding door panel. Like the control box and idler pulley, the belt bracket can be used with a variety of door models and is attached to the sliding panel by means of a door bracket that is specific to the door model in question. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings, wherein: 
       FIG. 1  depicts a motor/control assembly for an automatic sliding door in accordance with the present invention; 
       FIG. 2  depicts alternate configurations of the present invention that accommodate different automatic door models; 
       FIG. 3  is an exploded, perspective view of a motor/control assembly; 
       FIG. 4  is a more detailed view of the control box pictured in  FIG. 1 ; 
       FIG. 5  is an exploded, perspective view of the drive motor and its mounting components; 
       FIG. 6  depicts the transformer and power terminal block assembly in greater detail; 
       FIG. 7  shows the terminal block label for the sensor cable assembly; 
       FIG. 8  shows the terminal block label for the extended I/O cable assembly; 
       FIG. 9  shows a person blocking the path of opening doors in the “side screen” area; 
       FIG. 10  is an electrical power schematic of the control system of the present invention; 
       FIG. 11  is an exploded, perspective view of the motor/control assembly installed in an automatic door; 
       FIG. 12A  is a front plan view of the automatic door depicted in  FIG. 11  in the closed position; 
       FIG. 12B  is a front plan view of the automatic door depicted in  FIG. 11  in the open position; 
       FIGS. 13A and 13B  are front plan and side views, respectively of the upper belt bracket used to secure the moving door elements to the drive belt, as depicted in  FIG. 11 ; 
       FIGS. 14A and 14B  are front plan and side views, respectively of the lower belt bracket used to secure the moving door elements to the drive belt, as depicted in  FIG. 11 ; 
       FIG. 15  is an exploded perspective view of a door model-specific upper bracket mount assembly; 
       FIG. 16  is an exploded perspective view of the lower bracket mount assembly for the example door model depicted in  FIG. 15 ; 
       FIG. 17  is another example of a door model-specific upper bracket mount assembly; 
       FIG. 18  is the lower bracket mount assembly for the example door model depicted in  FIG. 17 ; 
       FIG. 19  is an exploded perspective view of universal extension bar kit for mounting brackets; 
       FIG. 20  shows an example of a door-specific chassis bracket; 
       FIG. 21  is another example of a door-specific chassis bracket; 
       FIG. 22  shows the idler assembly in greater detail; and 
       FIG. 23  shows an alternate drive scheme in which a transfer shaft conducts the drive power to the existing belt and drive mechanism from the original manufacturer. 
   

   DETAILED DESCRIPTION 
     FIG. 1  depicts a motor/control assembly for an automatic sliding door in accordance with the present invention. The motor/control assembly  100  includes a motor  110  that drives a pulley  111 , which in turn moves a belt attached to the sliding doors (not shown). An electronic control box  114  controls the operation of the motor  110  and pulley  111  via a motor cable  117 . 
   Sensor input to the control box  114  is provided by sensor cable assembly  115 , and an extended input/output (I/O) cable assembly  116  provides the control box  114  with input for special functions, e.g., emergency open. Also pictured in  FIG. 1  are unused leads  118  from the extended I/O cable assembly, which are folded over and enclosed in a wire duct. Such unused leads may be common when retrofitting the motor/control assembly  100  to preinstalled doors. The unused leads support functions that are rarely required. Therefore, providing access to these leads via terminal blocks would require additional foot print space on the assembly that would be wasteful from a product point of view. 
   A transformer  112  and power cable assembly  113  provide power to the control box  114 . 12VAC and 24VAC power is provided via terminal blocks for sensors that are external to the product. 
     FIG. 2  depicts alternate configurations of the present invention that accommodate different automatic door models. The functional components comprising the control assemblies  201 - 204  depicted in  FIG. 2  are essentially the same, but their spatial position relative to each other are different. This variation in component arrangement facilitates compatibility with different door configurations. For example, the motor  210  and pulley  211  on assembly  201  are on the right side, while assemblies  202  and  203  have their motors  220 ,  230  and pulleys  221 ,  231 , respectively, on the left side. 
   As a further variation, the motor/pulley combination on assemblies  202  and  203  are reversed. On control assembly  202 , the motor  220  is outside of the pulley  221 , whereas in control assembly  203 , the motor  230  is inside the pulley  231 . These more specific motor/pulley arrangements allow even greater flexibility in retrofitting preexisting doors, depending on, e.g., the length of travel of the doors, mounting points on the doors, etc. 
   As can be seen in  FIG. 2 , control assembly  204  does not have a motor and pulley. This configuration is suited for automatic doors that require the motor to be positioned in a way that cannot be achieved with the three other configurations depicted  201 ,  202  and  203 . In these cases the motor is mounted separately with its own brackets. 
     FIG. 3  is an exploded, perspective view of a motor/control assembly. This exploded view illustrates how the various components of the assembly can be combined into a universally applicable device by mounting them on a single aluminum extrusion  300 . The extrusion  300  serves as a chassis for the components and provides the basis for attaching the various mounting brackets. 
     FIG. 4  is a more detailed view of the control box  114  pictured in  FIG. 1 . This control box  114  may be an off-the-shelf component and provides functionality in accordance with ANSI 156.10-1999. The box has a series of light emitting diode (LED) displays  401 - 403  on the left side. LED  401  is the power indicator, LED  402  is the sensor indicator and program setting on/off indicator, and LED  403  is the program mode indicator. Next to these LEDs is the counter and program status indicator  404 , which monitors the operation of the control box  114 . 
   Located next to the counter/program status indicator  404  is a buzzer  405  that sounds in response to errors in the operation of the door. The buzz patterns comprise combinations of long and short buzzes, similar to Morse code, with each pattern corresponding to a specific type of error. For example, if there is an opening error and the door cannot slide open properly, the buzz pattern might be short, long, short, long, short. Examples of causes for an opening error include a door weight that exceeds operational limits, driving torque that is too weak for the door weight, or an object blocking the door. As another example, a specific buzz pattern might sound if the door runs a longer distance that the memorized door stroke due to, e.g., a loose belt or the doorstopper moving back. 
   A run/program switch  406  allows the operator to switch between normal operations and a testing/programming mode. When the switch  406  is slid into the Program position, the operator can test the door function by means of a test/pass button  407 . If the door operation is satisfactory, the operator pushes the set button  408 , and the settings are programmed. The run/program switch  406  is then switched back to the Run position. 
   The opening timer/direction switch  409  allows the operator to set the direction in which the automatic door will open as well as how long the door will be held open. For example, the door might be set to open left or right if there is only one moving door section, or in the case of two moving doors, the switch  409  can be set for bi-directional opening. The switch  409  also allows the operator to select between different “hold open” times, e.g., 4, 6, or 10 seconds. 
   Because the various sensors are part of the door, the present invention also provides a universal interface to the signals from these sensors by providing a controller than can respond to the various sensors irrespective of the specific door model. 
     FIG. 5  is a perspective view of the motor and its mounting components. In the preferred embodiment of the present invention, the motor  110  is a 40 W ( 1/20 HP) brushless, molded DC motor with an enclosed hypoid gear system. As can be seen is this perspective view, the timing pulley  111  is grooved along its contact surface to allow it to securely engage the belt that moves the sliding door(s). Also depicted is the motor cable  117  by which the control box sends commands to the motor  110  and by which the motor encoder sends signals to the controller. 
   The motor  110  can move the sliding doors (opening or closing) at speed of 4 inches per second to 29 in/s via 16 adjustable speed steps. The force of the moving doors can range from 40.0 pounds per square foot to 48.5 lb/sf. The gear reduction ratio of the motor  110  is 1:8.2. Encoder resolution uses 30 pulses per revolution and 246 pulses/revolution after gear reduction. The door travels 0.024″ per pulse. 
   The ends of the motor  110  are held between the mounting brackets  502  and mounting clamp  503  by rubber vibration isolation mounts  501 . These rubber mounts  501  absorb vibrations from the motor, providing quieter operation than would otherwise be the case without them. 
     FIG. 6  depicts the transformer  112  and power terminal block assembly in greater detail. The assembly to the left of the transformer  112  comprises three wires  601 - 603 . The first two  602 ,  603  are  115  lines, with one,  602 , leading directly to the transformer  112 , and the second  115  line leading to a 100 VAC terminal where it continues to the transformer  112  via wire  604 . The third wire  601  in this left side assembly is the ground wire. 
   The assembly to the right of the transformer  112  comprises most of the leads to and from the transformer. At the far end, two 100 VAC lines  604 ,  605  lead into the transformer  112 . A 12 VAC line  606 , a Common line  607 , and a 24 VAC line  608  lead back from the transformer  112 . 
     FIG. 7  shows the terminal block label for the sensor cable assembly. The label  700  is presented here as a proxy for the signal terminals. The first terminal in the assembly is the common  701 , followed by the half open terminal  702 , which is used when the automatic door is to be partially opened. This is typically done for extreme hot or cold weather. In such situations, the door is opened to a predetermined percentage of its full open stroke in order to conserve heating/cooling energy. This percentage is one of the definable parameters of the controller. For a bi-part door both doors are always operated in tandem; this is a safety requirement and is a practical reality as the doors are mechanically slaved to each other. The next terminal  703  relates to activation of normal automatic door function by, e.g., a motion sensor or pressure pad in the floor, and the safety terminal  704  relates to activation of the safety features that override normal door operation in response to a variety of safety signals or conditions such as mechanical feedback on the doors themselves, e.g., an object impeding door closing or a person or object blocking a safety sensor in the door path, or a signal from a side screen sensor, etc. 
     FIG. 8  shows the terminal block label for the extended I/O cable assembly. Again, the label  800  is presented as a proxy for the signal terminals. As with terminal block  700 , the first terminal for the extended I/O assembly is the common  801 . The next two terminals are the emergency open terminal  802  and emergency stop terminal  803 . The emergency open function would be activated in response to, e.g., a signal from a fire alarm. The emergency stop function generally comes from the breakout sensors; if the door is manually “broken out” (pushed open for an emergency exit) this condition is detected and any further drive to the door motor is stopped. 
   The ratchet function represented by terminal  804  relates to special activation of the door by means other than the normal motion or pressure sensors. “Ratchet” specifically means that a signal will cause the door to change open/closed states and stay that way until another ratchet signal is received, e.g., if the door is closed a ratchet signal will cause it to open and stay open indefinitely. When a subsequent ratchet signal is received the door will close and stay closed indefinitely. An example of a ratchet activation device is the handicap access buttons found on many automatic doors, which open the doors when the buttons are depressed. Similar ratchet activation buttons are used in hospitals to facilitate easier access of gurneys. 
   The side screen terminal  805  relates to sensors that detect objects or people blocking the path of the opening doors, as illustrated in  FIG. 9 . As the automatic doors  901 ,  902  open in response to an approaching person, the side screen sensor detects another person or object  910  standing the path of door  901 . In response, safety mechanisms will stop the doors  901 ,  902  from activating. However, once the door open sequence has been initiated the side screen signal is ignored, otherwise it would see the door itself moving into the space and never be able to open. 
     FIG. 10  is an electrical power schematic of the control system of the present invention. Electrical power from the facility  1001  is sent to the first terminal block  1002 , which has three positions: two 115 VAC terminals and a ground terminal. The transformer  1003  received the 115 VAC input from the first terminal block  1002  and produces 100 VAC, 24 VAC, and 12 VAC output to the second terminal block  1004 . The 100 VAC leads go to the controller  1005 , and the 24 VAC and 12 VAC leads power the sensors  1006 . 
     FIG. 11  is an exploded, perspective view of the motor/control assembly installed in an automatic door. The control assembly  1101  is mounted in the overhead frame  1108  of the door (always referred to as a “header” in the automatic door industry), as is an opposing contact pulley  1102 . The second pulley  1102  (belt idler assembly) is passive and its distance from the pulley on the control assembly  1101  defines the distance of movement for the sliding door panels  1106 ,  1107 . 
   Force from the motorized pulley on the control assembly  1101  is transmitted to the sliding doors  1106 ,  1107  via the drive medium (belt)  1103 . The drive belt  1103  that acts as the medium of power transfer can have many embodiments, e.g., 8 mm pitch, 10 mm wide HTD-type toothed drive belt or other type of belt. Alternatively, the drive medium can be a cable, roller chain, or any other drive type or hybrid combination. For purposes of the present invention, the specific drive medium used (belt, chain, cable, etc.) is not important, as long as it can transfer power from the motor to the sliding door panels. 
   Attached to each sliding door are fixed brackets  1104 ,  1105 , which in turn are attached to the belt  1103 . As can be seen in  FIG. 11 , one bracket  1104  attaches to the lower straight section of the belt  1103 , while the other bracket  1105  is attached to the upper section. This arrangement allows the sliding doors  1106 ,  1107  to move in opposite directions as the belt  1103  rotates clockwise or counterclockwise. 
     FIGS. 12A and 12B  are front plan views of the automatic door depicted in  FIG. 11 .  FIG. 12A  shows the automatic doors in the closed position, and  FIG. 12B  shows the open position. 
     FIGS. 13A and 13B  are front plan and side views, respectively of the upper belt bracket used to secure the moving door elements to the drive belt, as depicted in  FIG. 10 . 
     FIGS. 14A and 14B  are front plan and side views, respectively of the lower belt bracket used to secure the moving door elements to the drive belt, as depicted in  FIG. 10 . 
   Note that the upper and lower belt brackets depicted in  FIGS. 13 and 14  are incomplete in and of themselves. The upper and lower belt brackets are attached to the belt by the use of a belt clamp, described in more detail below. This is an important feature contributing to the universality of the invention. The belt brackets and belt clamp are used in almost all types of doors. The belt brackets are attached in turn to door brackets, which are specific to each type/brand of door. The interface between the universal portion of the invention and the brand-specific sliding panels of the door occurs between the belt brackets and the door brackets. 
     FIG. 15  is an exploded perspective view of a brand-specific upper bracket mount assembly. This example illustrates the assembly for a Keane Monroe 7000 door model. As explained above, the upper belt bracket  1501  and belt clamp  1502  are universal components that can be used on any door model. The belt (not shown) is held by the curved upper section of the belt clamp  1502 , which is then fastened to the belt bracket  1501 . Then belt bracket  1501  is in turn fastened to the brand specific door bracket  1503 , which is attached to the door  1504 . 
     FIG. 16  shows the lower bracket mount assembly for the Keane Monroe 7000 door model. Because the belt clamp  1602  in this facing upward for the lower bracket assembly, this view allows one to see the spaces  1605  in the belt clamp  1602  that accommodate “teeth” in the door belt (not shown). The belt clamp  1602  is mounted to the lower belt bracket  1601 , securing the belt in place. The belt bracket  1601  is then mounted to the door bracket  1603 , which in turn is mounted on the door  1604 . 
     FIG. 17  is another example of a brand-specific upper bracket mount assembly. This example assembly is for the Besam Unislide door model. Note that the upper belt bracket  1701  and belt clamp  1702  are identical to those in  FIG. 15 . As stated above, these are universal components of the invention and remain the same for all door models to which the invention is applied. The door bracket  1703  is specific to the particular mounting structure of the door  1704 . 
     FIG. 18  is the lower bracket mount assembly for the example depicted in  FIG. 17 . Again, the lower bracket  1801  and belt clamp  1802  are universal and identical to those in  FIG. 16 , but the door bracket  1803  is specific to the door  1804 . 
     FIG. 19  is an exploded perspective view of universal extension bar kit for mounting brackets. For several door models, a small amount of offset space is required between the door bracket and the belt bracket. The extension bar  1901  provides this offset. The bar  1901  has slots  1902 ,  1903  accommodating sliding rails  1904 ,  1905 . The lower bracket  1906  and upper bracket  1907  are then mounted to the rails  1904 ,  1905 , respectively, allowing them to be adjusted inward or outward as required by the specific application. The bar extension kit provides another universal element that can be adapted to the specific bracket space requirements of multiple door models. 
   The concept of door-specific mounting brackets is also applied to the motor/control assembly and idler assembly, which are both attached to the door header. Similar to the belt brackets, the goal here is to maximize the universal portion of the design. In this case the interface between door-specific components and universal components occurs between the door-specific header bracket(s) and the two primary assemblies: the controller/motor assembly and the idler assembly. A single type of header bracket was developed for each type of door. In some cases a right hand and left hand version of the bracket are required. In a few cases the bracket may be applied to multiple door types. 
     FIGS. 20 and 21  illustrate door-specific chassis brackets that can be applied to the present invention. As described above, specific configurations of motor/control components can be mounted onto a universal chassis. As with the belt brackets and clamps, this universal motor/control chassis can be mounted to a variety of door-specific mounting brackets, such as those depicted in  FIGS. 20 and 21 . 
     FIG. 22  shows the idler assembly in greater detail. As depicted in  FIG. 11 , the idler assembly provides an opposing contact for the motor on the control assembly to move the drive belt. The idler assembly is mounted onto the door header by means of a door-specific header bracket  2201 . In this example, the idler header bracket  2201  also includes an idler slide  2203  on which the contact pulley  2204  is mounted. The slide  2203  is used to adjust the position of the contact pulley  2204  via a thumbscrew  2202 , allowing for the fine-tuning of tension on the drive belt. 
     FIG. 23  shows an alternate drive scheme in which a transfer shaft conducts the drive power to the existing belt and drive mechanism from the original manufacturer. The idler assembly is designed for use with “I Beam” style door headers, which do not allow both the motor/control assembly and the idler assemble to be mounted on the same side. Therefore, the motor/control assembly is mounted on one side and transfers torque to a first contact pulley  2301  on the idler assembly. A transfer shaft  2304  transmits torque from the first contact pulley  2301  through an opening in the header bracket  2303  to a second pulley  2302  on the opposite side, where the conveyer belt and belt brackets are located to move the door panels. 
   Following the design approach described above, the present invention provides a largely universal product which is adapted to a variety of door types by developing just two door specific components: the door brackets and header brackets. This design allows for the upgrading and retrofitting of in-service doors without the need upgrade or replace the entire door system or to hunt down brand-specific replacement parts that may no longer be in production. 
   The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated.

Technology Classification (CPC): 4