US3084927A

US3084927A - Automatic door operator

Info

Publication number: US3084927A
Application number: US8640A
Authority: US
Inventors: Josef M Linder
Original assignee: Crown Industries Inc
Current assignee: Crown Industries Inc
Priority date: 1960-02-15
Filing date: 1960-02-15
Publication date: 1963-04-09
Anticipated expiration: 1980-04-09

Description

April 9, 1963 J. M. LINDER AUTOMATIC DOOR OPERATOR I5 Sheets-Sheet 1 Filed Feb. 15, 1960 mm T 0 mw V4 m F 2 x m w m 3 mm m m a 5 o 7 m 2 NZ I a w b 5 3 m u fl A 'OKNEYS 3 Sheets-Sheet 2 Filed Feb. 15, 1960 f /5 k 5 w 5 Q M 4 HM a 4 J 1 i W m g" y m a/ 4 Q ,7/ i: o ,a w KL M w g x k "l 5L @fi Q 4 a a W "w 6 H a "m Av 27 mh w I 7 a F 6L .50 m w M INVEN TOR. Jose; M. 4 l1v0 M24, Madam ATTORNEY;

ass-4,927 AWUMATIQ D0912 @PERATQR Josef M. Liuder, Delavan, Wia, assignor to frown Industries, EEC. Delavan, Wis, a corporation of Wiscousin Filed Feb. 15, 196i), Ser. No. 8,640 2 Qlaims. (Cl. 268-34) My invention relates to improvements in an automatic door operator.

More particularly stated this invention relates to that type of automatic door operator used to operate a swinging door under control of treadle switches of conventional characteristics but the actual door operating mechanism is liquid-controlled and involves novel features providing simplified liquid actuation; rapid acceleration and deceleration of door operation without destructive jerking of the door; a simplified single duct liquid system between power apparatus and the actual small door operating unit; liquid braking system in combination with spring bias to door closed position; and a novel combination of liquid and compressed air pressure maintenance whereby liquid pressure to the actual door operator is maintained for ready application of door moving forces.

It will be noted that the actual direct door operator is completely self-contained except for a single duct liquid pressure conduit and therefore there are no solenoids, limit switches or other electrical equipment immediately associated with the door operator.

In the drawings:

FIG. 1 is a perspective view, somewhat diagrammatically setting forth entrance and exit doors equipped with this invention.

FIG. 1A is a plan view fragmentarily showing a door and door frame with the door operator of this invention, the degree of door opening being shown in dotted lines.

FIG. 2 is a diagrammatic view showing the pressure liquid and electrical systems embodying the invention.

FIG. 3 is an elevation showing the door operator, the door frame and the top fragmentary portion of a door equipped in accord with this invention.

'FIG. 4 is a section on line 44 of FIG. 3.

FIG. 5 is an enlarged sectional view on line 55 of FIG. 4.

FIG. 6 is a section on line 6-6 of FIG. 5.

FIG. 7 is a vertical section through the reservoir and main pressure liquid control valve; the electromagnetic operators of the valves being shown in elevation.

FIG. 8 is a section on line 8-8 of FIG. 7.

FIG. 9 is a vertical section through the liquid pressure maintaining unit.

FIG. 10 is a section on line 10-10 of FIG. 7.

As shown in FIG. 1 a typical environment in which this invention may be used includes a door 10 or a pair of doors Ill-11 which are mounted to swing upon hinges such as those shown at 12 for door 10 it being understood that door 10 is mounted in frame 13 for swinging motion toward the viewer and door 11 is mounted in its frame 14 for swinging motion away from the viewer. In a suitable position, in this case at the top of the door frame 13 the actual door operator 15 is mounted to the door frame in such position that a door operating arm 16 forming a part of the door operator 15 and extending therefrom is attached at its outward swinging end to a lost-motion bracket 17. A similar door operator 15' shown in dotted lines in FIG. 1 is mounted on the other side of the door frame 14 in position to swing door 11 to open position and permit it to close.

There are available on the market various means com prising treadles 1'8, 19, 20, and 21, each equipped with a pressure operated switch responsive to the pressure exerted upon the treadle when a person approaches a door or when gagement with housing 47.

Patented Apr. 9, 1963 such a person steps on a treadle after going through the door opening. Assuming that door 10 and its associated treadles 18-19 are concerned in a particular installation, it will be seen upon examination of FIG. 2 that treadle 18, when provided with the weight of an approaching person, will close a switch 25 in a circuit including the secondary in a transformer 26 and door opening wire 27 for energization of coil 28. Some form of time delaying mechanism shown diagrammatically at 29 gives assurance that door opening switch 30 will not open immediately when the weight of the person is removed from treadle 18. Also when the weight of the person leaves treadle 13 and bears on treadle 19 holding switch 31 which is a pressure switch beneath treadle 19 will be closed so as to delay still further the opening of switch 30 until the person has cleared the zone in which the door swings. When the weight of the person is removed from treadle 19 door 10 may close.

This being the environment in which my invention is to be incorporated it will be understood that when the switch 30 is closed, my door operator now to be described will be activated and when the door operator has been described my new control means therefore will be more readily understood.

Reference has already been made to the fact that the door operator 15 or 15' is equipped with a door operating arm 16. As shown in FIGS. 3 to 5 this arm 16 is fixed upon a sturdy oscillatable shaft 35 extending upwardly through the box-like casing 36 of operator 15. This casing comprises an upper and a lower substantial frame plate 37, 38 respectively, spaced apart by frame posts 39 at the corners of the casing. It is between the frame plates 37 and 38 that the principle structural elements of the door operator, other than arm 16 are housed, and there is a cover plate 40 to complete the enclosure on three sides thereof exposed to public view when the operator is installed against the

frame

13 or 14 as shown in the drawings.

The at rest position of arm 16 is its position when door It) is closed and the arm 16 with its shaft 35 is biased to this position by a heavy helical spring 45, the inner end of which as shown in FIG; 4 in dotted lines is hooked into engagement with shaft 35 at 46. The outer end of the spring 45 is hooked to a cylindrical spring housing 47 as shown at 48 so that the spring may be placed under tension by revolving the cylindrical spring housing 47 and then engaging pawl 49 in one of many notches 50 as shown most clearly in FIGS. 3 and 4. It will be understood that pawl 49 is pivotally mounted upon a screw 51 in threaded engagement with frame plate 38 and a spring 52 constantly urges the pawl 49 into en It will be understood that this is a relatively permanent adjustment for the life of a particular spring.

The mechanism thus far described assures that operator 15 installed as shown in FIG. 1 will move the hinged door 10 to closed position with such degree of closing force as is adjustably determined by the bias of spring 45 eX- erted for oscillation of shaft 35 and arm 16.

Also fixed upon shaft 35 is a piston operated arm 55 so disposed with respect to shaft 35 and arm 16 that when door ltlis closed the arm 55 is in the position shown in FIG. 4. This means that the outer end of the arm 55 being provided with a pivotal connection at '56 to piston rod 57 will have disposed the piston rod in its extremeinner position relative to cylinder 58. It willbe understood that cylinder 58 and piston 59 comprise a double acting liquid responsive door actuator for liquid pressurewhich may be termed a braking function as will now be described.

Referring now to the diagram in FIG. 2, it will be seen that the double acting cylinder and piston arrangement is provided with a liquid pressure supply duct 60 and a connection 61 for liquid is connected to the other end of the cylinder. Each of the

tubes

66 and 61 is provided with a check valve 62 to prevent passage of liquid from the cylinder, but tube 60 has a by-pass 63 and tube 61 has a by-pass 64; and each of the by-passes has a cam operated needle valve, 65 for by-

pass

63 and 66 for 'by-pass 64, so arranged that thepre'ssure of liquid leaving the cylinder 58 is relieved by the particular needle valve and a cam between the ends of the two needle valves may adjustably close a valve or permit the valve to open.

The two check valves and their respective by-passes are each provided with a separate valve cage shown in FIG. 4 at 70 and '71 and it will be understood that the cam 67 is mounted upon shaft 72 to which as shown in FIG. 4 a cam arm 73 is fixed. This cam arm is connected to piston operator arm 55 by means of damping pitman 74 and the angular relation of the piston operated arm 55, the damping pitman 74-, cam arm 73, and cam 67 is such that as piston 59 approaches the inner end of the cylinder 53 as shown in FIG. 2 to force liquid out of the left end of the cylinder through duct 60, needle valve 65 is held closely to but not actually upon its seat so as to slow up the motion of the piston. Also it will be understood that as the piston 59 approaches its outer limit of motion (toward the right as seen in FIG. 2) the relationship of the parts is such that cam 67 will then be holding needle valve 66 close to but not against its seat so as to slow up the motion of the piston in that direction.

While the diagrammatic disclosure in FIG. 2 explains the general functional arrangement of parts relating to these by-pas'ses and the control thereof, FIG. shows an englarged detail of the bypass duct through cages 7i and 71 and shows a mounting block 75 shaped to carry bearing member 76 for shaft 72 and to provide guideway for a cam follower 77 and the cam of valve 65; also for cam follower 78 mounted on the cam end of valve 66, and there are

compression springs

79 and 30 respectively for these needle valves tending to urge the valves and their followers to cam contacting position. Suitable lock nuts 82 are provided to secure whatever threaded adjustment there may be provided between the respective valves and their followers.

Because cylinder 58 is mounted to a post at 90 which is in pivotal relation to frame plates 37 and 38 the

valve cages

70 and 71 and mounting block 75 are secured in unitary assembly with a plate 912 and each of the valve cages 70 and '71 being provided with a very heavy tubular connection at 93 and 94 respectively with cylinder 58 the swinging motion of this assembly in accord with the arcuate path of the connection at 56 is accommodated. Also inspection of FIG. 3 will show the manner in which a surge tank 95 is secured to this assembly under the cylinder so that surge conduit 96 connected at the bottom of the surge tank 95 may pass to that tank and receive from it liquid which will fill the cylinder 58 to the right of the piston 59 as seen in FIG. 2.

Having thus described the relatively conventional treadle apparatus and electrical connections adjacent the doors and 11, and having described the door operating mechanism of this invention, attention is now directed to the control means and apparatus for power operation of the piston and cylinder 59-58.

The secondary of the transformer 26 referred to above is also used as a low voltage source for a circuit 100 controlled by a float switch 101 whereby a motor 102 may be energized by the line as indicated in FIG. 2. This motor is mechanically connected directly through coupling 103 with a positive displacement pump 104 which is only energized when reservoir 105 has a' sufficient supply of reserve liquid 1&6 to cause float switch 101 to 61 be closed. At such times the pump withdraws liquid from the reservoir through supply tube 197 and forces it through pressure tube 108 into liquid pressure tank zone 109. 1 refer to this portion of tank 111 as a liquid pressure zone because that portion of tank 111 lying above a flexible and elastic diaphragm 110 comprises an air pressure zone provided initially and constantly with air 'at adequate pressure so that the liquid at 109' is available under pressure for functional operation of the cylinder and piston at Sit-59. A suitable air valve 112 is provided for supply of air by means of an air pump or other air connection and this air under pressure remains in the zone above the diaphragm as a quickly responsive means for forcing liquid through pipe 113 into cylinder 58 whenever the door is to be opened. That portion of pipe 113 shown in dotted lines iii FIG. 3 is flexible to accommodate movement of the cylinder.

A master valve 115 in pipe 113 determines when the liquid pressure is to be applied to the piston for door opening operation. The electrical control of this master valve will now be described.

When the door opening switch 3%) closes, it energizes cell 122, the armature 123 of which is pulled upwardly (See FIGS. 2 and 7) so as to mechanically overcome the pressure upon master valve 115 theretofore impressed upon that valve by valve stem 124 and its compression spring 125. The pressure of spring 125 is adequate to hold the master valve 115 to its seat against the pressure in the chamber 111 above diaphragm 110. Immediately upon the release of the mastervalve 115 the liquid from the supply at 1119 under pressure is supplied to the cylinder 58 and a door opening operation results, since the pressure maintained in chamber 109 is adequate to overcome the spring 45 which has theretofore held the door in closed position.

The door, having been opened in the manner described, will stay open so long as the treadle 18 or the treadle 19 sustains sufficient weight to close the switch 25 or 31, but when the weight is relieved from the treadle, switch 30 will open, coil 122 will be de-ener'gized and the master valve will be forced to return to closed position under pressure of spring 125. Whereupon liquid pressure at the left of piston 59 as seen in FIG. 2. will be relieved through by-pass 63 at a rate governed by the position of cam 67 and the liquid will be returned through return duct 126. p

FIG. 7 shows not only the master valve 115 but also shows a complete master valve arrangement for control of another door thus providing means for control of a companion door operator, as for instance, door 11 under control of treadles 20 and 21.

Resume From the above description it will be seen that pump 104 and its motor 102 under control of float switch 101 will-pump liquid from reservoir into liquid pressure tank 109 against the diaphragm which is under pressure of air in tank 111. Therefore, it is the pressure provided initially and thereafter according to the pressure of air supplied through valve 112 that determines the forces with which piston 59 is caused to overcome the spring 45 and open the particular door to which the piston and its red are connected.

When master valve is opened, the movement of the valve to close the return duct 126 is immediate so that the liquid from pressure tank 109 cannot pass into reservoir 105. But when the door has been opened and its related treadles have been relieved of pressure, the de-energiz'ation of coil 122 permits the immediate closure of the master valve and spring 45 is permitted to return the piston to the left as seen in FIG. 2 under control of needle valve 65 in turn controlled by cam 67. This cam is oscillated in accord with the movement of pitman 74. Therefore, the final portion of the door movement to closed position is slowed. The needle valve approaching its seat permits only :a relatively slow bleeding of the liquid firom cylinder 58 around the bypass 63 and into reservoir 105. Of course, in accord with this invention, the door opening movement under pressure of the liquid moving into the cylinder is rapid until cam 67 moves to push the needle valve 66 to a position relative to a bypass 64. Then the liquid to the right of the piston 59 as seen in FIG. 2 may slowly pass into surge tank 95 as will be clear in the above description. Surge tank 95 has a certain amount of air in the upper portion thereof to act as a very low pressure cushion and tank 95 therefore need not be vented.

The capacity of reservoir 105 and of pressure tank 109 is ample to supply a number of door operators and each door operator as shown in FIGS. 3, 4, and 5 need only be provided with a single high pressure line 113 with a master valve 115.

I claim:

1. A door operator and operating system therefore to open a framed door biased to closed position in said frame and equipped with a treadle operated control switch, an hydraulic operated cylinder and piston assembly mechanically connected to the frame and to the door and including an arm attached to the door for swinging motion responsive to the position of the piston in the cylinder, an electric circuit including a source of current and said treadle switch with a coil of a magnetically responsive master valve; said valve having a cage comprising a portion of an hydraulic system including said cylinder, a liquid filled reservoir, a motorized pump, an air cushioned pressure tank and hydraulic connections between these elements whereby the pump fills the pressure tank and supplies liquid under pressure through said master valve to the cylinder; an electric circuit for said motor including a float operated switch in said reservoir energized by closure of said switch, the cage of said master valve being provided with a by-pass connected to the reservoir whereby to return liquid from the cylinder to the reservoir when the master valve is closed to prevent passage of liquid from the pressure tank to the cylinder, said master valve being biased to closed position by means adequate to overcome the pressure of liquid from the pressure tank.

2. The operator and system of claim 1 in which the cylinder and piston comprise a double acting assembly in which one end of the cylinder is connected to the master valve and the other end of the cylinder is provided with a hydraulic surge tank connection, and adjustable needle valves respectively positioned to control liquid flow from either end of the cylinder, said needle valves being connected for adjustable response to the position of the arm.

References Cited in the file of this patent UNITED STATES PATENTS 2,276,338 Potter et a1. a Mar. 17, 1942 2,893,725 Katz July 7, 1959 2,911,210 Ferguson Nov. 3, 1959 FOREIGN PATENTS 1,094,963 France Dec. 15, 1954

Claims

1. A DOOR OPERATOR AND OPERATING SYSTEM THEREFORE TO OPEN A FRAMED DOOR BIASED TO CLOSED POSITION IN SAID FRAME AND EQUIPPED WITH A TREADLE OPERATED CONTROL SWITCH, AN HYDRAULIC OPERATED CYLINDER AND PISTON ASSEMBLY MECHANICALLY CONNECTED TO THE FRAME AND TO THE DOOR AND INCLUDING AN ARM ATTACHED TO THE DOOR FOR SWINGING MOTION RESPONSIVE TO THE POSITION OF THE PISTON IN THE CYLINDER, AN ELECTRIC CIRCUIT INCLUDING A SOURCE OF CURRENT AND SAID TREADLE SWITCH WITH A COIL OF A MAGNETICALLY RESPONSIVE MASTER VALVE; SAID VALVE HAVING A CAGE COMPRISING A PORTION OF AN HYDRAULIC SYSTEM INCLUDING SAID CYLINDER, A LIQUID FILLED RESERVOIR, A MOTORIZED PUMP, AN AIR CUSHIONED PRESSURE TANK AND HYDRAULIC CONNECTIONS BE-