Patent Publication Number: US-5893236-A

Title: Power operator for sliding plug doors

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     This invention relates generally to power operated doors for mass transit vehicles and more particularly concerns door operators of the type wherein big-parting door panels are moved into and out of a pocket opening in the side wall of a transit vehicle and over and away from said opening to permit passenger travel into and out of said vehicle. Generally speaking, plug doors are used on vehicles where, in a closed and plugged position, the door panels are positioned in a pocket opening in the vehicle side wall, thereby becoming in a closed and plugged position, essentially part of the side wall. This type of construction minimizes interference with the car structure and presents an uninterrupted car body surface. 
     Plug doors have been in use for a substantial period of time. Operators of this kind are disclosed in U.S. Pat. Nos. 5,142,823 and 5,483,769. In addition, a certain plug door operator bearing the trade name ESCO-DOOR and marketed by Transferia Tebel also provides plug door operation. 
     Although the above mentioned operators are reasonably effective, certain shortcomings have been encountered in use, particularly in respect to complicated linkages between the electric prime mover and operator carriage, resulting in reduced reliability. Other shortcomings of these earlier designs include spring actuated over center locking of the plug and plug carriage, use of telescoping hangers incorporating poorly controlled door motion for individual door panels, and lever actuated plugging/unplugging links operated by extended motor shafts. 
     The invention disclosed herein overcomes the above-mentioned difficulties through the use of an integral carriage containing all operator elements. The plugging and unplugging movement is obtained through the use of a single shaft drive motor mounted on the carriage providing both panel door motion and plug/unplug motion through the use of planetary gearing. 
     Also, guidance for the door panel lower edges is provided by a lever operated vertical shaft actuated by the carriage during plugging and unplugging movements into and out of the car door pocket. 
     Therefore, an object of this invention is to provide a powered door operator for bi-parting door panels including plugging and unplugging operations wherein the entire drive system is mounted on a carriage movable into and out of the car door pocket. 
     It is a further object of this invention to provide a powered plug door operator for bi-parting doors wherein a combination of planetary and straight gearing provides door panel movement over and away from an opening in the car side wall and door panel plugging into a car side wall door pocket. 
     It is a further object of the invention to provide a plug door operator wherein in the door closed and plugged position doors are held in the door pocket through over-center linkage geometry. 
     It is yet an additional object of the invention to provide a plug door operator wherein individual bi-parting door panel hangers are of a simple non-telescoping design. 
     SUMMARY OF THE INVENTION 
     The plug door operator disclosed herein utilizes a single carriage containing all elements of the drive. Mounted on a base plate overhead of an opening in a car door side wall, the carriage of the operator disclosed herein is moved into and out of a pocket formed in the car side wall through the use of a single motor with multiple gearing. Door panel movement is provided by dual counter-rotating helical drives, each gear driven from the single shaft electric prime mover. A single hanger mounted on individual transverse slides provides controlled deflection of the panel hanger combination. The plugging motion is also provided from the single shaft prime mover through the use of the combination of curved track and epicyclic planetary gearing operating a plug/unplug shaft. Linkage utilized provides an over-center lock in a plugged position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects and advantages will become apparent upon reading the following detailed description and upon reference to the drawings, in which: 
     FIG. 1 shows the operator of the invention attached to bi-parting doors in an open condition, particularly showing the juxta positioning of the non-telescoping hangers. 
     FIG. 2 shows the operator of the invention wherein the plug door operator has moved the door panels into a fully closed, unplugged position, showing position of panel hangers. 
     FIG. 3 shows the operator of the invention wherein the door panels are in a fully closed and plugged position inside a pocket in a car side wall. 
     FIG. 4 shows a partial view of the operator of the invention from a view vantage opposite to FIGS. 1 and 2, particularly showing the operator to car body mounting the plug/unplug carriage and the carriage cover showing attached plug/unplug shaft brackets. 
     FIG. 5 is an additional partial view of the operator of the invention having the cover plate removed, thereby providing an improved view of the operating components, particularly showing the carriage/base plate slides. 
     FIG. 6 is a partial tearaway view of the operator of FIG. 5, particularly showing the plug/unplug shaft and linkage configuration with the carriage and base plate locked by over-center linkage position. 
     FIG. 6A is an additional view of the plug/unplug linkage arrangement of FIG. 5, more particularly showing the base/carriage in an unlocked condition. 
     FIG. 7 is an additional partial view of the operator of the invention, particularly showing the plug/unplug link, gears, and plug/unplug track. 
     FIG. 8 is an partial tearaway view of the operator of FIG. 7, particularly showing curved track-door hanger connection. 
     FIG. 9 is an additional partial view of the operator of the invention from the external vantage point, particularly showing the plug/unplug and helical gear drive components. 
     FIG. 10 is a partial tearaway of the operator of FIG. 9 showing the helical drive member gearing in greater detail. 
     FIG. 11 is a partial tearaway view of the operator of FIG. 9, particularly showing the carriage-base plate plug/unplug tracks and cover mounting brackets. 
    
    
     DETAILED DESCRIPTION OF OPERATION 
     With reference to FIGS. 1, 2 and 3, there is shown the operator assembly 2 of the invention disclosed herein mounted on base plate 4 overhead of pocket opening 5 in a car body (not shown). As shown, bi-parting door panels 9 and 15 having apertures or windows 10 and 16 are driven over and away from a door opening 5. The panels are mounted on door hangers 8 and 14 operating on door slides 27 and 24, respectively, for lateral motion there along. The door hangers 14 and 8 are driven for bi-parting motion of door panels 9 and 15 along door slides 24 and 27 by helical drive members 20 and 21. Door slides 24 and 27 are mounted on carriage assembly 6. Carriage assembly 6 is mounted on base plate 4 for limited transverse movement, i.e., in and out of door opening 5, on door base plate tracks 29 located at either end of base plate assembly 4. To facilitate this transverse movement, carriage assembly 6 includes at either end cooperating track and rollers 30 (reference FIGS. 9 and 11). 
     The door opener carriage assembly 6 includes a carriage cover and support member 7 cooperating with a plurality of associated support brackets 31 for mounting and positioning operating elements as described below. Means for guiding the lower edges of door panels 9 and 15 are provided by bottom track 3. 
     With particular reference to FIGS. 4, 5, 8 and 9, the carriage assembly 6 further includes upper and lower helical drive members 20 and 21 journaled for rotary motion on support brackets 31. Also mounted on carriage assembly 6 at end plates 11 (reference FIG. 11) are upper and lower door slides 24 and 27. 
     Also mounted on carriage assembly 6 is drive motor 35 and planetary gear drive assembly 38. The output shaft gear 39 of planetary gear drive assembly 38 (reference FIG. 10) cooperates with pinion gears 40 and 41 to provide rotary motion of helical drive members 20 and 21. Intermediate drive motor 35 and planetary gear drive 38 is a planetary output gear 36. Gear 36 cooperatingly drives sector gear 45 attached to plug/unplug shaft 48 (reference FIG. 6). 
     Plug/unplug shaft 48 is journaled on support brackets 31 for rotary motion and at each end has plug/unplug levers 51 and 50 at either end of plug/unplug shaft 48. Plug/unplug levers 50 and 51 are linked to the base plate 4 by carriage base plate links 52 and 53, respectively. Links 52 and 53 are suitably attached to the base plate 50 as shown. Links 52 and 53 have operative ends. As applied, the rod ends have spherical journaling providing limited degrees of link motion relative to the link end attachment, thereby greatly simplifying proper adjustment of the plug/unplug motion. 
     In particular reference to FIGS. 6 and 6A, the combination of lever 50 and link 52 as designed, provides an over-center lock for the carriage assembly 6 when plug shaft 48 has rotated plug/unplug 50 to its fully clockwise position as shown. 
     Reciprocal motion of door panels 15 and 9 is obtained through counter-rotation of helical drive members 20 and 21 by gears 39, 40 and 41 and associated door panel movement by attachment of hangers 8 and 14 to drive nuts 22 and 23 (reference FIG. 9). 
     Also attached to the drive nut 23 (reference FIGS. 7 and 8), is a roller cam arm 28 cooperatively engaged with groove 13 of base plate plug track 12 for guiding carriage assembly 6 into and out of a fully closed and plugged position (reference FIGS. 7 and 8). 
     Movement of arm 28 in the cam surface 13 of plug track 12 provides transverse movement of the carriage assembly when door panels 9 and 15, after full closing, move into a closed and plugged position. 
     In operation, from a configuration as shown in FIG. 1, with the door panels in a fully opened position, energization of drive motor 35 rotates gears 39, 40 and 41 in the directions shown in FIG. 10. Rotation of gears 40 and 41 correspondingly rotate helical drive members 20 and 21, thereby moving drive nuts 22 and 23 from a position at the extreme end of drive members 20 and 21 (reference FIG. 9) to opposite ends of drive members 20 and 21. Movement of drive nuts 22 and 23, attached to door hangers 14 and 8, respectively, have now moved door panels 9 and 15 into a fully closed, but unplugged position, as shown in FIG. 2, roller cam 28 affixed to hanger 8 has approached the initial portion of groove 13 of base plate plug track 12. Upon further rotation of drive motor 35 the higher torque encountered due to the fully closed position of door panels 9 and 15 and movement of roller cam 28 in groove 13 of track 12 results in rotation of planetary drive output gear 36, thereby rotating sector gear 45. Rotation of sector gear 45 rotates plug/unplug shaft 48, thereupon plug/unplug levers 50 and 51 and acting through links 53 and 52 move the entire plug/unplug carriage assembly 6 guided by base plate track 12 into the door pocket of opening 5 in the car side wall, thereby completing the plugging operation. 
     Upon reverse rotation of drive motor 35, door opening proceeds in an identical manner. 
     It should be noted that movement of the carriage assembly into a fully plugged position incorporates an over-center lock of shaft 48 by rotation of shaft 48, thereby moving plug/unplug links 52, 53 from an unlocked position shown in FIG. 6A to a locked position shown in FIG. 6. Although FIGS. 6/6A show link 52, link 53, which is attached to the opposite end of plug/unplug shaft 45, operates identically. 
     Thus, it is apparent that there has been provided in accordance with the power operated plug door operator disclosed herein an operator that fully satisfies the objects and advantages as set forth above. While the operator disclosed has been described in conjunction with a specific embodiment thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications and variations as fall within the spirit and broad scope of the appended claims.