US1773243A

US1773243A - Closure operator

Info

Publication number: US1773243A
Application number: US200857A
Authority: US
Inventors: Duncan J Stewart
Original assignee: Individual
Current assignee: Individual
Priority date: 1927-06-23
Filing date: 1927-06-23
Publication date: 1930-08-19
Anticipated expiration: 1947-08-19

Description

Aug. 19,1931). D. .1. STEWART CLOSURE OPERATOR Filed June 25, 1927 3 Sheets-Sheet 1 INVENTOR Duncan LI SLELJRPZ ATTORNEYS Aug. 19, 1930. D. J. STEWART CLOSURE OPERATOR Filed June 23, 1927 3 Sheets-Sheet 2 INVENTOR Lmmm CI E a-13ft ATTORNEYS Aug. 19, 1930.

D. J. STE WART CLOSURE OPERATOR Filed June 23, 1927 3 Sheets-Sheet 5 F 5. INVENTOR Duncan LI SLELJATL TORNEYJ TU LINE Patented Aug. 19, 1930 UNITED STATES PATENT OFFICE DUN CAN J. STEWART, OF ROCKFORD, ILLINOIS, ASSIGNOR TO HOWARD I). COLMAN, OF ROCKFORD, ILLINOIS CLOSURE OPERATOR Application filed June 28,

This invention relates to closure opera tors and more especially to power-driven operators such as are commonly used to open and close heavy garage or factory doors.

It is often desirable for a person wishing to enter or leave a garage or factory building to use the doorway normally provided for the use of vehicles. For this purpose it is unnecessary and infact undesirable, especially in cold Weather, to open the door full width. Where the door is intended to be used by vehicles and is adapted to be opened or closed by a power operator, the operator must be started once to open the door and again to close it. Therefore, when a person desires to use such a door,it would be necessary for him to operate the control device to start the operator to open the door and then to Wait until the door has been opened before actuating the control device to close the door.

An important object of the present invention therefore is to provide a new and improved poWer-driven operator for a door which is operable by the actuation of one control device to open the door full width so that a vehicle or the like may pass through the doorway, or by the actuation of a difierent control device to cause the door tobe only partially opened as to allow persons to enter or leave the building and then after a slight delay to be automatically returned to closed position. In this particular the present invention constitutes an improvement over the closure operator which forms the subject of a copending application of Howard D. Colman and Duncan J. Stewart, Serial No. 139,277, filed October 4, 1926.

A more detailed object of the invention is to provide a motor-driven door operator each cycle of operation of which is initiated by closing a single switch and terminated by opening said switch, there being two independently operable control devices, one adapted to initiate each normal opening or closing cycle, and the other adapted to cause the door to be opened part way and then automatically closed. v

Another object is to provide an operator adapted when started to open and then automatically close the door, a novel means being 1927. Serial No. 200,857.

provided to delay the operation of the operator in closing the door.

A further object is to provide an operator having a novel means by which the operator may be caused to execute operating cycles of different lengths whereby to move a closure member different distances from open or closed position.

Other objects and advantages of the invention will become apparent from the following detailed description taken in connection 'with the accompanying drawings, in which:

Figure 1 is a fragmentary view in vertical section of the driving unit of the operator.

Fig. 2 is a sectional view taken along the plane of line 22 of Fig. 1.

Fig. 3 is a detail view showing a reversing switch.

Figure 4 is a fragmentary side elevation of the power driving unit taken from the side of the unit opposite from which Fig. 1 is taken.

Fig. 5 is a fragmentary plan section of the doors and a portion of the operator.

Fig. 6 is an elevational view of a lost-motion connection employed for determining the lengths of the door operating cycles.

Fig. 7 is a perspective view of the parts shown in Fig. 6. a

Fig. 8 is a theoretical wiring diagram.

While the invention is susceptible of various modifications and alternative constructions, I have shown and herein describe in detail the preferred embodiment but it is to be understood that I do not thereby intend to limit the invention to the specific form disclosed but intend to cover all modifications and alternative constructions falling within the spirit and scope of the invention as expressed in the appended claims.

In its exemplary form shown in the drawings, the invention is embodied in a door operator of the type disclosed in a copending application by Howard D. Colman, Serial No. 166,086, filed February 5, 1927, the operator in the present instance being adapted to actuate a pair of sliding doors 10 (Fig. 5). These doors may be mounted in abutting relation in a common plane so that they may be moved apart to open the doorway and together to close the doorway, the latter position of the doors being shown in Fig. 5.

Mounted on the ceiling or other suitable stationary support is a bracket 11 (Fig. having a bearing 12 in which a drive shaft 13 is Ournaled centrally and in perpendicular relation to the doorway. As its forward end, the shaft 13 carries a pinion 14 meshing at diametrically opposite sides with two rack bars 15, the free ends of which may be slidably supported b pipes 16. Rollers 17 mounted on the brac et 11 serve to hold the rack bars in mesh with the pinion 14. The inner end of each rack bar is rigidly connected by a link 18 to a fixture 19 secured to the door on the opposite side of the doorway from the pipe supporting the rack bar. Thus, it will be seen that upon rotation of the shaft 13 in opposite directions both of the rack bars will be reciprocated simultaneously to open or close the doors.

The shaft 13 is connected by a universal coupling 20 to a drive shaft 21 of the power driving unit which is shown particularly in Figs. 1 and 2. This unit includes a frame structure generally designated by the numeral 22 and adapted to be mounted on the ceiling or other suitable support, an electric motor 23 having a driving connection with the shaft 21, and mechanism for controlling the starting, stopping and direction of rotation of the motor in successive door operating cycles.

The motor shown herein is of the singlephase induction type adapted to be operated by alternating current and having a main field winding 24 (Fi 3) and a starting field winding 25. Frefera bly, the motor is mounted on the frame 22 with its shaft 26 alined with the drive shaft 21 as shown in Fig. 2, the connection between the motor shaft and the drive shaft including a centrifugally-operated clutch 27 and a speed reducing gearing 28 of the planetary type. The clutch 27 includes a plate 29 on a sleeve 30 arranged to rotate with the motor shaft through the medium of a flexible coupling 31. Pivoted on the plate 29 are a pair of dogs 32 disposed within a drum 33 which is fixed to a shaft 34 on which the sleeve 30 is rotatably mounted. Thus, it will be observed that when the motor starts to rotate, the dogs 32 will be swung outwardly by centrifugal action against the tension of springs 35, thereby gripping the internal surface of the drum when a redetermined speed has been attained. y similar action the clutches disconnect the motor shaft and the shaft 34 as the motor slows down in stopping. After such disconnection the motor, due to the inertia of its rotor, will continue to rotate for a brief interval.

The planetary gearing 28 which is of well known construction, comprises a pinion 36 meshing with gears 37 on flying studs 38 carried by plate 39 which is rigid with the drive shaft 21. The gears 37 mesh with the internal teeth of a ring gear 40 which is normally held stationary by a spring pressed dog 41. Thus, in the rotation of the pinion 36 the shaft 21 rotates at a reduced speed.

The means for controlling the operation of the motor and therefore the movements of the doors, comprises a main motor switch 42, a brake 43, a reversing switch 44 (Figs. 3 and 8) and means for actuating these control devices in proper sequence under initial manual control. The motor switch includes contact terminals 45 stationarily mounted on the frame 22 and cooperating with terminals 46 carried by a bar 47 which. extends through an opening 48 in the frame and is disposed above the drum 33. This bar constitutes a lever which has a floating mounting, that is, the fulcrum of the lever is shiftable from one point to another so that the lever may execute a plurality of different control movements in pivoting about different fulcrums. To provide such a mounting, the bar is pivoted intermediate its ends on a stud 49 which in turn is carried by a rocker member 50 pivoted at 51 on the stationary frame 22.

The brake 43 consists of a block (Fig. 2) of friction material carried by the lever 47 in position to be pressed into a peripheral groove (Fig. 2) in the drum 33 by a strong tension spring 53 attached to the bar 4?.

Normally, that is, when the motor is at rest, the forward end of the lever 47 is held in raised position by a latch 54 pivoted at and yieldingly pressed in beneath the lever by a spring 56. The lower end of the latch constitutes the armature of a control magnet 57 which when energized serves to trip the lever 47 by removing the latch. lVhen thus released, the lever swings under the action of the spring 53 to release the brake and close the main motor switch, the stud 49 at this time providing a stationary fulcrum for the lever. This initiates the operation of the door operating cycle during which the doors are moved either to open or closed position, depending on the direction of rotation of the motor.

Means is provided for actuating the control lever 47 to terminate each door-operating cycle by stopping the motor and reconditioning the control lever 47 for operation in the next cycle. This means includes a control shaft 58 (Figs. 1 and 5) mounted for oscillation on the frame 22 and having a lost-motion connection with the drive shaft 21. Carried by the shaft 58 and operating upon a follower arm 59 rigid with the rocker member 50, is a cam device comprising two disks 60, one fixed to the shaft 58 and having a lobe 61 with oppositely inclined surfaces 62, the other disk having a pin-and-slot connection 64 with the first disk and being provided with a lobe 65 having radially extending surfaces 66. Since the lobe 65 is'shiftable relative to the lobe 61, the two diskswhen oscillated in either direction, cooperate to provide a cam having an inclined leading surface formed by the lobe 61 and an abru t trailing surface formed by the lobe 65, t e latter surface being positioned by shifting of the lobe 65- by'engagement between the follower 59 and the leading surface 66 of the lobe 65.

In the oscillation of the cam device toward the follower 59, the follower will be swung in a direction to cause the stud 49 to be raised and then suddenly released as thetrailingcam surface 6 passes beyond the follower. At this time, the main switch 42 is closed and in the upward movement of the stud, the lever 47 is swung upwardly about a fulcrum formed by the upper edge of the opening 48 in the frame. The latch 54 is thus allowed to move in beneath the lever 47 to hold the forward end of the lever in raised position. Thereafter, when the abrupt surface of the cam passes the follower, thereby releasing the stud 49, the rear end of the lever swings downwardly under the action of the spring 53 to open the main motor switch and apply the brake, thereby terminating the cycle of operation. The upper end of the latch 54 constitutes the fulcrum for this movement.

The lost motion connection between the drive shaft 21 and the control shaft 58 I through the medium of which the shaft 58 is I 7. This connection comprises a series of

disks

67, 68, 69 and 69 arranged in coaxial relation on the end of the shaft 58 opposite the cam device, and each of the

disks

67, 68 and 69 has a lost-motion connection with the ad-. jacent disk. Thus,in the operation of the drive shaft 21 the disks are. picked u successively, and finally when the last isk' is picked up, the cam shaft will be actuated.

In the present instance, the innermost disk 67 is in the form of a spur gear loosely mounted on the shaft 58 and geared to the drive shaft 21 through a speed-reducing

connection comprising gears

70 and 71, the latter meshing with a inion 72 on the drive shaft. The disk 69 1s keyed or otherwise fixed to the control shaft 58 and the disk 69 is adapted to be made rigid with the disk 69 by tion of the door as indicated in Fi 7 means extending through coinciding holes 7 0 and 71 formed respectively in the

disks

69 and 69. These holes provide for rotary adjustment of the disk 69 relative to the shaft 58.

. Projecting outwardly from the gear 67 beyond the disk 68 is a lug 73 which is adapted to engage with a radiallyextending lug 74 on thedisk 68 after the gear has revo ved through nearly one revolution either from a position corresponding to the closed posi- ,,or rom its position when the doors are open. The lug 74 has an outwardly extending portion 75 whichprojects over both of the

disks

69 and 69 in position to engage a radially projecting lug 7 6 on the disk 69* when rotating in a clockwise direction indicated by the arrow in Fig. 7, as will be the case when the doors are being opened or to engage a similar lug 76 on the disk 69 when the disk 68 is being rotated in a counterclockwise direction during the door-closing cycle.

Sincethe disks

69 and 69 are rigid with the shaft 58, engagement of either of the lugs 76 or 76 by the lug 74 causes the shaft 58 to be oscillated in the direction of rotation of the gear 67 thereby terminating the operating cycle by actuating the reversing switch, opening the main motor switch, and applying the brake in a manner described above.

As above stated, the lug 74 engages the lug 76 to terminate the door-closing cycle and therefore the slack portion of the lost-motion connection must be so adjusted that the shaft 58 will'be oscillated as the doors approach their closed position. The proper adjustment .of the disk 69 to accomplish this result may be effected by manually rotating the drive-shaft 21 when disconnected from the doors in a direction corresponding to the door-closing cycle and until the slack of the lost-motion connection has been taken up and the cam shaft 58 properly oscillated and then, with the doors in closed position, slipping the rack-bars 15 into mesh with the pinion 14. The lug 7 6 may then be positioned so that it will be engaged by the lug 74 after the doors have been opened full width, thereby oscillating the cam shaft 58 to terminate the door-opening cycle. This may be accomplished by rotating disk 69* so as to bring the lug 7 6* into proper position and then inserting means such as a screw through the coinciding holes in the two disks.

It will be apparent that with the lostmotion connection above described, the operating cycles of the power-driving unit may be varied as desired. Furthermore, since the connection provided is composed of compactliy arranged rotary elements and therefore oes not rely on a reciprocatory member for its operation, the closure operator may be located at any convenient distance from the door and if necessary, the drive shaft 21 may even be located in parallel or angular relation with respect to the plane of the doorway. Such an arrangement is particularly adapted for use with door operators having rotary as distinguished from reciprocatory actuating members.

Referring to Fig. 3, the reversing switch comprises two connector lates 77 and 78 rigidl mounted on a she t 58 adjacent the cam isk and insulated from each other. The plates have radially extending arms adapted to engage

stationary spring contacts

79, 80, 81 and 82 on an insulating plate 83. When the cam shaft 58 is positioned as shown in Figs. 2 and 3, the plate 77 connects the

contacts

79 and 80 and the plate 78 connects the

contacts

81 and 82. In the other position of the cam shaft, the

contacts

80 and 81 are connected by the plate 77 while the

contacts

79 and 82 are connected by the plate 78.

Referring to the wiring diagram in Fig. 8, the main field 24 of the motor is connected to one alternating current power line 84 and to one contact 45 of the switch 42. The switch member 46 is connected by a conductor 85 to the other power line 86.

As is common practice in the construction of single-phase induction motors, the starting field 25 is connected in series with a switch 87 which is intended to be opened to cut out the starting-field after the motor has attained a predetermined speed and torque on starting. This switch is usually associated with the rotor of the motor so as to be opened by centrifugal action after the motor has started and to be closed automatically when the motor is at rest or substantially so. The starting-field is connected to the contacts 7 9 and 81 of the reversing switch.

The reversing switch contact 82 is connected to a contact 45 of the main switch l2 by a conductor 88 while the contact 80 is connected to the power line 84 by a conductor 89. Thus, it will be seen that the connection of the starting-field to the power lines is governed by the main switch 42 and that the connection betwen the starting-field and the power lines will be reversed upon each oscillation of the cam shaft .58.

The latch magnet 57 for controlling the starting of the motor in each door-operating cycle is interposed in a conductor 90 which leads from the conductor 88 to a switch 91. This switch is connected by a conductor 90 to the power line 86 and is adapted when closed to complete the energizing circuit for the latch magnet 57. Preferably, the switch 91 is of the push-button type.

Opermfiz'on in opening the (Zoom full width The operation of the control mechanism in each operating cycle of the motor is as follows: assuming the parts to be positioned initially as shown in Figs. 1 and 3. Under these conditions the main motor switch 42 would be open, the brake would be applied to the drum 33,the centrifugal switch 87 would be closed because the motor is at rest, and

contacts

79 and 81 would be connected respectively with contacts 80 and 852. Now, by closing the switch 91, the energizing circuit for the latch magnet is established as follows: From the power line 86, conductor 90, switch 91, conductor 90, magnet 57, conductor 88,

contacts

82 and 81, starting field 25, switch 87, contacts 79 and 8t), conductor 89 to the power line 84. Energization of the magnet 57 withdraws the latch 54 thereby allowing the spring 53 to swing the control lever 47 about the stud 49 as a pivot center, the stud being at this time held stationary by reason of the engagement between the follower 59 and the cam disks 60. This movement of the lever releases the brake and closes the main motor switch 42 which connects the main motor field to the power lines and also establishes an energizing circuit for the starting held 25 as follows: From the power line 86 through the conductor 85, switch 42, conductor 88,

contacts

82 and 81, starting field 25, switch 87 which is still closed,

contacts

79 and 80, conductor 89 to the power line 84. Thus, the motor is started in a direction corresponding to the position of the reversing-switch and rotation thereof causes the rack bars 16 to be moved to open or close the doors. lVhen speed of the motor reaches the predetermined point, the centrifugal force acting on the switch 87 will be suilicient to overcome the tendency of the switch to remain closed. Opening of this switch breaks the circuit for the starting field which is included in the energizing circuit for the starting magnet 57.

If, in the operating cycle thus initiated, the motor rotates in a direction to open the doors, the gear 67 will rotate in a clockwise direction as indicated by the arrow in Fig. 7. In such rotation, the lug 73 engages the lug 74 after about one revolution, the disk 68 being picked up so as to rotate with the gear 67. After about another revolution otthe gear 67, the portion 75 of the lug 74 engages the lug 76 on the disk 69 thereby causing the cam shaft 58 to be oscillated to terminate the cycle since the lost motion in the connection between the

shafts

21 and 58 has been taken up. Such oscillation of the cam shaft 58 causes an inclined surface 62 of the cam device to actuate the follower 59 to raise the stud 49. This raises the forward end of the lever 47 about the upper edge of the openin 48 as a fulcrunnand against the action of the spring 53, the latch being therebv allowed to swing in beneath the lever 47 iecause the magnet 57 is at. this time deenergized. Thus the lever 47 is reset for the next door operating cycle. Thereafter the cam device releases the follower 49 and the spring swings the rear end of the control lever downwardly, the upper end of the latch 54 being the fulcrum during this movement. In this way, the main motor switch is opened quickly and the brake is applied to the drum 33, the motor being thereby stopped and the control mechanism is left in proper position for the next cycle of operation.

The next energization of the starting magnet will start the motor in the opposite direction and such rotation causes the doors to be moved to closed position. In such rotation, the gear 67 rotates in a counter-clockwise direction and after about one revolution the lug 73 picks up the disk 68 by enga mg the side of the lug 74 opposite to that w ich was engaged during the door-opening cycle. After part of another revolution the portion 75 of the lug 74 engages the lug 76 thereby oscillating the disk 69 and therefore the shaft 58 in a direction opposite to the oscillation of the shaft which terminates the door-opening cycle. Oscillation of the cam shaft terminates the door-closing cycle in the same way as in the door-opening cycle. At the end of this cycle the elements of the lost-motion connection will be positioned as shown in Fig. 7, and the other parts of the control mechanism will be conditioned for the initiation of a door-opening cycle when the starting magnet 57 is again energized.

Attention is directed to the fact that with the control mechanism above described the motor cannot continue to operate in one direction longer than the time requiredto complete one operating cycle. That is to say, the main motor switch will always be opened to stop the motor at a predetermined point in each cycle and cannot again be closed to restart the motor until the motor has slowed down sufiiciently sothat the switch 87 will close. This result is accomplished as above described by connecting the magnet 57 in a control circuit leading through the centrifugally operated switch 87 in the starting field circuit which switch is responsible to the speed of the motor and which, being common to the starting field circuit and to the magnet control circuit, renders the starting field inoperative while the motor is running and at the same time prevents energization of the latch magnet. This motor control arrangement involving the use of the centrifugally operable switch for preventing energization of the magnet 57 and restarting of the motor in the normal cycle of operation until the speed of the motor has fallen below a predetermined value is disclosed and generically claimed in my co-pending application Serial No. 181,661, filed April 7, 1927.

Partially opening and automatically closing the doors To cause the doors to be partially opened and then automatically closed so as to permit a person topass through the doorway, means is provided which is operable by the actuation of an independent control device to establish an energizing circuit for the starting magnet 57; to shorten the lost-motion connection between the shafts'21 and 58 so that the operator will execute a shorter cycle of operation; to condition the starting circuit so that it will be closed automatically after the doors have been partially opened; and to restore the normal character of the lost-motion connection and the starting circuit while the doors are 35 being closed. As shown in Fig. 8, the means is deenergized, the armature is positioned as,

shown by the dot-dash lines in Fig. 6, but when the magnet is energized, the armature is drawn upwardly into full line position, thereby closing a switch 97 to complete a locking circuit for the magnet 93. This circuit includes the magnet 93, contact terminal 98, and the armature 95 which is connected to the conductor 90 The armature also constitutes the movable member of a switch 99, the stationary member of which is formed by a terminal contact 100 connected by a conductor 101 to the conductor 90. Thus, it will be seen that the switch 99 is electrically in parallel with the starting switch 91 used for operating the doors through their normal full stroke. Therefore, the energizing circuit for the magnet 57 may be completed when the switch 87 is closed either through the switch 91 or through the switch 99, the latter being closed by energization of the magnet 93 by closure of the switch 92.

The lost-motion connection between the

shafts

21 and 58 is shortened to cause the door opening cycle of the operator to be terminated when the doors are in partially open position by rendering the

elements

68 and 69 of the connection inoperative. To this end, a flapper 102 is pivoted on a disk 103 rigid with the shafts 58 and is adapted to be swung into position to be engaged by the lug 73 on the gear 67 when the latter has rotated a predetermined distance, about one revolution in the resent instance. In the form illustrated, t e flapper is substantially U- shaped in form and is swingable in a plane including the axis of shaft 58 by reason of its pivotal mounting on a disk 103. This disk is secured to the disk 69" and therefore is made rigid with the shaft 58 by means of a screw 104 (Fig. 4) extending through one of a plurality of holes 105 and a pair of coinciding holes and 71 in

disks

69 and 69. The holes 105 allow for rotary adjustment of the flapper relative to thelug 73 and therefore permit the length of the lost-motion connection between the flapper and the gear 67 to be varied. Preferably, the flapper is adjusted so as to be in vertical position when the doors are closed, in which position it will tend to swing downwardly by gravity.

The upper end of the flapper has a surface 106 (Fig. 5) which may be positioned to be engaged by the lug 73 1n the rotation of the gear 67 in a clockwise direction as indicated by the arrow in Fig. 7, and an inclinedsurface 107 adapted to be engaged by a lug 108 when the gear is rotated in a counterclockwise direction. The latter lug extends through an opening 109 in the gear 67, and is pivoted at 110 near one end of the opening against which end it is held by a spring 111.

The flapper is normally in the position indicated by the dot-dash lines in Fig. 6 and is moved into the full line position by an extension 112 of the armature 95. Preferably, the extension engages the flapper at a point substantially in alinement with the axis of the shaft 58 so that engagement between the extension and the flapper will be maintained even though the flapper is oscillated with the cam shaft.

Operation in partially opening and automatically closing the doors With the parts ositioned as shown by the dot-dash lines in ig. 6, the doors will be partially opened and then automatically closed whenever the manually operable switch 92 is closed momentarily. Closure of this switch energizes the magnet 93 whose armature 95 is thereby moved to the full line position shown in Fig. 6. This closes the

switches

97 and 99 and moves the flapper 102 into position to reduce the slack in the lost-motion connection between the

shafts

21 and 58. Closure of the switch 97 completes the lockin circuit for the magnet 98 while closure of t e switch 99 energizes the starting magnet 57 by completin the circuit which has been described above in detail in connection with the operation of the doors by the switch 91, this circuit being through the reversing switch 44: and the centrifugal switch 87 which at this time is closed since the motor is at rest. Thus, the brake is released and the main motor switch is closed to start the motor in a direction to open the doors.

:When the motor has attained a predetermined speed the centrifugal switch 87 is opened automatically thereby breaking the ener izing circuit for the latch magnet 57 wine circuit would otherwise be held closed since the locking circuit maintains the switch 99 closed. In the initial rotation of the gear 67, the lug 108 thereon engages the surface 106 of the flapper (see Fig. 5) but passes by the flapper owing to its pivotal mounting. After the gear has rotated through about one revolution, the lug 73 strikes the surface 106 of the flapper, thereby connectin the gear to the shaft so that in the continue rotation of the gear the shaft will be oscillated. This resets the latch 54 for the control lever, actuates the reversing switch so that the starting field connections will be conditioned to cause a reverse rotation of the motor in the next cycle, opens the main motor switch 42 and applies the brake, the operating cycle being thereby terminated with the doors part way open.

is held open. Closure of the switch 87 will take place when the motor has come substantially to rest. This automatically completes the energizing circuit for the starting magnet 57 because at this time the switch 99 is held closed by the magnet 93. Energization of the starting magnet trips the lever 47, thereby starting the motor in a direction to close the doors.

In the closing cycle of operation, the gear 67 rotates in a direction opposite to that of its previous movement and in such rotation carrice the lu 108 against the surface 107 of the flapper. he lug 108, being held against pivotal movement by the end of the opening 109, cams the flapper outwardly and this in turn moves the armature 95 to open the

switches

97 and 99, thereby breaking the locking circuit for the magnet 93. The flapper and armature are then free to swing outwardly by the action of gravity into the position indicated in dot-dash lines in Fig. 6, the lost-motion connection being thereby restored to its normal length.

Near the end of the door-closing cycle, the lost-motion connection operates in its regular way, that is, b engagement between the lug 74: and the lug 6, to actuate the cam shaft 58 thereby terminating the cycle when the doors reach their closed position. Thus, at the completion of the closing cycle of operation, the control mechanism is conditioned for operation in the next cycle either to open the doors full width by closure of the switch 91 or to again partially open and automatically close the doors under the control of the switch 92.

It will be observed that at the end of the cycle during which the door is partially opened, the continued rotation of the motor after disconnection from the doors by operation of the centrifugal clutch serves to hold the switch 87 open and therefore delays the initiation of the door closing cycle. Such delay allows sufiicient time for a person to pass through the doorway and effectually prevents damage to the motor that might result if it were possible to reverse the motor connections while the motor is running at or near normal speed.

It will be noted that if the switch 92 normally used to initiate a partially opening cycle of operation should be closed when the doors are open, an energizing circuit for the starting magnet 57 will be established in the usual way and the doors will be completely closed, the locking circuit for the magnet-93 being broken during the first revolution of the gear 67.

I claim as my invention:

1. A door operator having, in combination with a door, a motor, means providing a driving connection between said motor and the door, a reversing switch operable to control the direction of rotation of said motor in opening and closing said door, a main motor switch operable when closed to start said motor thereby initiating a door-operating cycle corresponding to the position of said reversing switch, means operating automatically to actuate said reversing switch and open said main switch after the doors have been moved through a predetermined distance thereby terminating the cycle, manually operable con trol means by which said main switch may be closed to initiate the normal door-operating cycle, and a second manual control means operable independently of said first mentioned control means to initiate a door-operating cycle and to condition said automatically operable means so that it will terminate the ey cle after the door has been moved a predetermined shorter distance than in the normal 0 cle.

2. A mechanism of the character described having, in combination with a door, a motor driven opertor associated with the door and adapted to open andclose the door alternately in successive cycles of operation, a switch for controlling either operating cycle of said motor, automatically operable means to open said switch thereby terminating the normal cycle'of operation of said operator, and means operating under manual control to initiate a cycle of operation by closing said switch and to condition said automatically operable means for the execution of a cycle of operation which is shorter than said normal cycle.

3. A mechanism of the character described having, in combination with a door, a powerdriven operator associated with said door and operable to open and close the door alternately in successive cycles of operation, means opcrating automatically to terminate each dooroperating cycle, said means being normally conditioned to cause the operator to move the door a predetermined distance in opening or closing, manually cont-rolled means to initiate the normal cycle of operation of said operator, and independent manually controlled means to initiate a cycle of operation of said operator and to condition said automatic means for the execution of the cycle shorter than said normal operating cycle.

4. A door operator having, in combination with a door, a motor, a driving connection for transmitting the power of the motor to the door for opening and closing the same, means mechanically associated with said connection through a lost-motion device and operable automatically to terminate each cycle of operation when the lost-motion in said device has been taken up, manually controlled means for initiating the normal cycle of operation of said motor, and a second control means operable to initiate the operation of.

said motor and to reduce the lost-motion in said device thereby causing the operator to execute a predetermined cycle which is shorter than said normal cycle.

5. A door operator having, in combination with a door, an electric motor, a driving shaft driven by said motor "and operatively connected to said door, a driven shaft having a lost-motion connection with said driving shaft, means operated from said driven shaft for stopping the motor to terminate each door operating cycle, and means by which said lost-motion connection may be shortened to cause said motor to execute a cycle which is shorter than the normal cycle.

6'. A door operator having,-in combination with a door, a motor operatively connected to the door, a switch for starting the motor to initiate each door operating cycle, two independently operable control devices by which said switch may be closed to start said motor, and a single means for opening said switch to terminate each operating cycle automatically, said last mentioned means being operable to cause an operating cycle of one length to be executed when the cycle is initiated by one of said control devices and to cause a cycle of a different length to be exeouted when the cycle is initiated by said other control means.

7. A door operator having, in combination with a door, an electric motor operatively connected to the door, a single switch adapted when closed to initiate a cycle of operation of said motor and when opened to terminate the cycle, two independent starting means for controlling the closing of said switch, and switch actuating mechanism operable automatically to terminate said cycle after a predetermined movement of the doors when the cycle is initiated by one of said starting means and to terminate the cycle after a predetermined shorter movement of the doors when the cycle is initiated by said other starting means.

8. A power driving unit having, in combination with a closuremernber to be operated thereby, an electric motor, a driving shaft driven by said motor and operatively connected to said closure member, a driven shaft, means operating in the oscillation of said driven shaft to stop the motor and thereby terminate the operating cycle, and a plurality of coaxially arranged rotatable elements cooperating to provide a lost-motion connection between said driving and driven shafts whereby to determine the length of each door operating cycle.

9. A power driving unit having, in combination with a closure member to be operated thereby, an electric motor, a driving shaft driven by said motor and operatively connected to said closure member, a driven shaft. means operating in the oscillation of said driven shaft to stop the motor and thereby terminate the operating cycle, and a series of coaxially arranged rotary elements each having a lostmotion connectionwith the adjacent element of the series, the elements at opposite ends of the series being connected respectively to the driving and driven shafts.

10, A power driving unit having, in combination with a closure member to be operated thereby, an electric motor, a driving shat't driven by said motor and operatively connected to said closure member. a driven shatt. means operating in the oscillation of said driven shaft to stop the motor and thereby terminate the operating cycle, a series of coaxially arranged rotary elements each having a lost-motion connection with the adjacent element. and means for rendering certain of saidelements inoperative whereby to reduce the lost motion between said shafts.

11. A closure operator having, in combi nation with a door to be operated thereby, an electric motor, a shaft operatively associated with said door and adapted to be driven by said motor in opposite directions in successive cycles of operation, means for stopping said motor to terminate each operating cycle, actuating means for said stopping means having a lost-motion connection with said shaft, and selectively operable means for varying the amount of lost-motion in said connection whereby to vary the length of the door operating cycle.

12. A closure operator having, in combination with a door to be operated thereby, a motor, a driving shaft driven by said motor and operable to open and close the door upon rotation of the motor in opposite directions, means operable to stop said motor and thereby terminate the door operating cycle, means providing a lost-motion connection between said driving shaft and said stopping means, the length of said connections determining the length of the normal door operating cycle, means operable under manual control to shorten said connection whereby to shorten the door operating cycle, and means operating in the succeeding operating cycle to restore said connection to its normal length.

13. A closure operator having, in combination with a door to be operated thereby, an electric motor adapted to open and close the door upon rotation in opposite directions, means for stopping the motor to terminate each cycle of operation, means normally operable in the rotation of said motor to actuate said stopping means after a predetermined movement of said door, and manually controllable means for changing the character of said actuating means whereby to cause the actuating means to terminate the operating cycle after the doors have moved a predetremined shorter distance than in the normal operating cycle.

14. A closure operator having, in combination with a door to be operated thereby, an electric motor adapted to open and close the door upon rotation in opposite directions, means for stopping the motor to terminate each cycle of operation, means normally operable in the rotation of said motor to actuate said stopping means after a predetermined movement of said door, and manually controllable means for changing the character of said actuating means whereby to cause the actuating means to terminate the operating cycle after the doors have moved a predetermined shorter distance than in the normal operating cycle, and means operating automatically in the succeeding operatingcycle to render said last mentioned means inoperative.

15. An operating mechanism having, in combination with a door, a drive shaft adapted to open or close the door upon rotation in opposite directions. an electric motor, a centrifugal clutch operable to transmit the power 01"" said motor to said shaft when the motor is rotating above a predetermined speed and to disconnect said motor and said shaft when the motor is running below said predetremined speed whereby to prolong the rotation of the motor after such disconnection, and a switch operable after the termination of one cycle of operation of said motor and in the subsequent rotation thereof to automatically restart said motor for the execution of another cycle.

16. An operating mechanism having, in combination with a door, a motor, a clutch operable by centrifugal action when the motor is rotating above a predetermined speed to connect said motor to the door and to disconnect the motor whereby to allow for prolonged rotation of the motor above a predetermined speed due to its inertia, an electromagnetic switch for starting said motor in a direction to move the door from open to closed position, and means for energizing the magnet of said switch after the termination of a door-opening cycle whereby to automatically close the door, said last mentioned means including a switch responsive to the speed of the motor after disconnection in the prolonged rotation of the motor from said door by the operation of said clutch.

17. An operating mechanism having, in combination with a door, a motor, a centrifugally operated clutch for transmitting the power of said motor to the door, and means operating in the prolonged rotation of the motor resulting from disconnection thereof by said clutch at the end of one door operatmg1 cycle to initiate automatically another cyc e.

18. An operator for opening and automatically closing a door having, in combination with a door, a motor rotatable in opposite directions in successive operating cycles, means by which the power of said motor is transmitted to the door, control mechanism operable automatically to terminate the dooropening cycle of said motor means operable to permit the motor to rotate by its own inertia after the termination of the normal cycle, said last mentioned means including an automatic clutch for disconnecting the motor from the door, and means operating automatically in the rotation of said motor after operation of the clutch to start the motor in direction to close the door, the movement of the door to closed position being thereby delayed for a predetermined interval after the termination of the door-opening cycle.

19. An operating mechanism having, in combination with a door, a motor rotatable in opposite directions in successive operating cycles to open and close the door, means to control said motor to open said door, means operating automatically to control said motor whereby to close the door, and means for delaying the operation of said last mentioned means including a centrifugal clutch inter-- posed between the motor and the door and operable to disconnect the motor from the door and thereby prolong the rotation of the motor.

20. A closure operator having, in combination with a door to be operated thereby, a motor, a driving connection for opening and closing the door alternately in successive cycles of operation of said motor, a main motor switch, means operating automatically to terminate each door operating cycle by opening said switch, an electromagnet adapted when energized to cause said switch to be closed whereby to start said motor, an energizing circuit for said magnet including a switch which is open only when the motor is running above a redetermined speed, another switch opera le under manual control to start the motor when the door is in closed position and means operable to hold said last mentioned switch closed during the dooropening cycle so that the circuit for said magnet will be completed automatically by closure of said speed responsive switch at the termination of the door-opening cycle.

21. A closure operator having, in combination with a door to be operated thereby, a motor, a driving connection for opening and closing the door alternately in successive cycles of operation of said motor, a main motor switch, means operating automatically to terminate each door-operating cycle by opening said switch, an electro-magnet adapted when energized to cause said switch to be closed whereby to start said motor, an energizing circuit for said magnet including a switc 1 adapted to be held open by centrifugal action in the rotation of said motor, another switch operable under manual control to cause the motor to be started in a direction to open said door, and means for holding said last mentioned switch closed while the door is being opened.

22. A closure operator having, in combination with a door to be operated thereby, a motor, a driving connection for opening and closing the door alternately in successive cycles of operation of said motor, a main motor switch, means operating automatically to terminate each door operating cycle by opening said switch, an electromagnet adapted when energized to cause said switch to be closed whereby to start said motor, an energizing circuit for said magnet including two switches in series one operable under manual control, the other being operable automatically and adapted to be open when the motor is running and closed when the motor is at rest or substantially so, means for maintaining said manually controlled switch closed while the door is being opened including an electromagnet and a locking circuit therefor, and means operating while the door is being closed to break said locking circuit.

23. A closure operator having, in combination with a door to be operated thereby, a motor, a driving connection for opening and closing the door alternately in successive cycles of operation of said motor, a main motor switch, means operating automatically to terminate each door operating cycle by opening said switch, an electro-magnet adapted when energized to cause said switch to be closed whereby to start said motor, an energizing circuit for said magnet including two switches in series one operable under manual control, the other being operable automatically and adapted to be open when the motor is running and closed when the motor is at rest or sub stantially so, and means for maintaining said manually controlled switch closed while the door is being opened including an electromagnet and a locking circuit therefor.

24:. A closure operator having, in combination with a door to be operated thereby, a motor, a driving connection for opening and closing the door alternately in successive cycles of operation of said motor, a main motor switch, means operating automatically to terminate each door operating cycle by opening said switch, an electromagnet adapted when energized to cause said switch to be closed whereby to start said motor, two parallel energizing circuits each including said magnet, a switch in one of said circuits adapted when closed to complete the circuit thereby initiating a cycle of operation of said motor, a switch in said other circuit also adapted when closed to initiate acycle of operation of the motor, means for holding said last mentioned switch closed at the end of one door operating cycle, and a switch in said last mentioned circuit operable after the termination of one operating cycle to close the circuit automatically to initiate a succeeding cycle of operation.

25. A power driven operator having, in combination with a closure member to be operated thereby, a driving unit operatively associated with said member, means having a lost motion connection with said unit for determining the range of movement of said closure member by the unit, and manually operable means for varying the amount of lost motion in said connection to change the range of movement of said closure member.

26. A power driven operator having in combination with a closure member to be operated thereby, a driving unit operatively associated with said member, means having a lost motion connection with said unit for determining the range of movement of said closure member by the unit, and electromag netic means for varying the amount of lost motion in said connection to change the range of movement of said closure member.

2'2. A power driven operator having, in combination with a closure member to be operated thereby, a motor operatively associated with said member, means having a lost motion connection with said motor for determining the range of movement of said closure member, manually operable means for starting said motor and changing the amount of lost motion in said connection to change the range of movement of said closure member.

28. A universal power driving unit for doors having difierent operating movements comprising, in combination, a frame, a motor mounted on said frame, a shaft on said frame driven from said motor and having one end arranged for operative association with different kinds of doors, a switch controlling the operation of said motor, and means controlling said switch to define an operating cycle of the motor depending upon the character of the door with which said shaft is connected, said last mentioned means including a second shaft mounted on said frame and operatively associated with said switch, and means independent of said connection between said first shaft and said door providing an adjustable lost-motion connection between said shafts.

29. A universal operating unit for doors combining a frame, a motor thereon, a shaft on said frame connected to said motor and adapted to be connected with the door to be operated, a member controlling the duration of operation of said motor in successive operating cycles and actuating means for said member including a lost-motion device interposed between said shaft and said member, said device being separate from the connection between said shaft and said door whereby to define a predetermined number of revolutions of said shaft independently of said connection.

30. A universal operating unit for doors combining a frame, a shaft mounted on said frame and adapted for association with different kinds of door operating mechanisms, 21 motor for driving said shaft, and means on said frame for defining the duration of opera tion of said motor in operating said door, said last mentioned means being operated from said shaft independently of the connections between the shaft and the door to be operated.

In testimony whereof I have hereunto affixed my signature.

DUNCAN J. STEWART.