US1909131A - Door control means for elevators - Google Patents

Door control means for elevators Download PDF

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US1909131A
US1909131A US240304A US24030427A US1909131A US 1909131 A US1909131 A US 1909131A US 240304 A US240304 A US 240304A US 24030427 A US24030427 A US 24030427A US 1909131 A US1909131 A US 1909131A
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elevator
door
contacts
relay
energization
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US240304A
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Harold W Shonnard
Harold J Fear
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ELEVATOR SUPPLIES CO Inc
ELEVATOR SUPPLIES COMPANY Inc
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ELEVATOR SUPPLIES CO Inc
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B13/00Doors, gates, or other apparatus controlling access to, or exit from, cages or lift well landings
    • B66B13/02Door or gate operation
    • B66B13/14Control systems or devices
    • B66B13/143Control systems or devices electrical

Description

May 16, 1933.
H. w. SHONNARD ET AL 1,909,131
DOOR CONTROL MEANS FOR ELEVATORS Filed Dec. 15, 1927 3 Sheets-Sheet 1 y 16, 1933- H. w. SHONNARD ET AL 1,909,131
DOOR CONTROL MEANS FOR ELEVATORS Filed Dec. 15, 192'] 3 Sheets-Sheet 2 INVENTOR HAROLD 1 14 J/w/v/m/w 6% #49010 J. FEAR May 16, 1933.
H. w. SHONNARD ET AL ,909,131
DOOR CONTROL MEANS FOR ELEVATORS Filed Dec. 15, 1927 3 Sheets-Sheet I:
INVENTORJ f/ACQUZZ? WHO/VAWPJ fr/7672010! FFAR Patented May 16, 1933 UNITED STATES PATENT QFFICE HAROLD W. SHONNARD AND HAROLD J. FEAR, OF MONTCLAIR, NEW JERSEY, ASSIGN- ORS TO ELEVATOR SUPPLIES COMPANY, INC-., OF IIOBOKEN, NEW JERSEY, A COR- PORATION OF NEW JERSEY DOOR CONTROL MEANS FOR ELEVATORS Application. filed December 15, 1927.
This invention relates to elevators, and particularly to elevators provided with power means for opening and closing the elevator gate or for opening and closing the doors at the various landings as the elevator approaches and stops at such landings, or to those provided with means for controlling both the elevator gate and landing doors.
The present invention provides certain improvements in such gate and door operating means. Principal among these improvements are, first, the provision of novel and improved means for effecting, maintaining, and'cutting off the electrical energization of the prime mover constituting the principal operating force; and secondly, the specific inter-relation, arrangement and method of oporation ofthe parts involved in the system, as will become more apparent from the study of the following description when read with reference to the accompanying drawings, wherein:
Figure 1 presents a view in elevation taken from within the elevator and showing the elevator gate and the landing doors at one landing, together with the operating means therefor. I
Figure 2 is a diagram showing schematically the preferred arrangement and method of controlling the electrical parts and circuits involved in the operation of the system.
Figure 3 is a similar schematic showing of a modified method of control.
Referring to the drawings wherein the preferred embodiment of the invention is illustrated and wherein like reference characters refer to like parts throughout the several views, the character 1 designates an elevator adapted to travel in either direction along the hatchway 2, the elevator being provided with suitable suspension means (not shown) adapted to be controlled from the elevator hoisting motor (whose armature H is shown schematically in Figure 2). he elevator hoisting motor is in turn adapted to be controlled through circuits (not shown) operable by the manipulation of the elevator onerators control lever, or car switch, as it is commonly termed in the art, shown at 6 in Figures 2 and 3.
Serial No. 240,304.
The elevator 1 is provided with a gate 7, and as illustrated in Figure 1 the gate is shown as of the collapsible type; but obviously other constructions may be employed. A gate operating arm 8 is shown connecting with the gate 7. This operating arm 8 is adapted to be oscillated back and forth to effect opening and closing movements of the elevator gate 7, the means preferably employed for effecting this oscillation consisting of an adjustable rocker plate 12 anchored preferably to the roof of the elevator as indicated at 13, at which location the arm 8 is affixed thereto, preferably by the provision of a pivot pin 15. This rocker plate 12 is in turn adapted to be oscillated or rocked in response to the alternate rotations of the prime mover; the power transmitting means in the preferred embodiment, as shown in Figure 1 consisting of a train of gears 17, 18, 19 and 20, a shaft 21 on which the gear 20 is mounted, a crank 22, and a connecting link 23. The gear 20 is preferably provided with a cam-shaped portion 24 adapted to actuate alternately the switch arms 26 and 27 'to open the switches 0L and CL respectively, as the gear rotates first in one direction and then the other. The function of these switches will appear hereinafter.
Also, in the preferred embodiment of the invention, means are provided for cushion ing the final movement of the elevator gate and the associated landing doors as they approach the final stage of movement in either the opening or closing direction. As shown in Figure 1 such means consists of a doubleacting liquid check 25 in which a member is connected so as to have a movement corresponding to that of the gear 20 and prime mover 16. This member has associated therewith means for retarding its progress during its final stage of movement in each direction. anism 25 may, of course, vary to suit the circumstances attending any particular installation, the liquid check just described being that type disclosed and claimed in the co-pending application of Harold W. Shennard for an Adjustable door operator, Se-
The structure of this cushioning mechrial No. 93,086, filed March 8th, 1926, now Patent 1,716,567 issued June 11, 1929.
Each landing at which the elevator 1 ma stop is provided with a door or doors pre I erably of the type shown at the landing indicated in Figure 1, where a door is-show-n'eom sisting of two sections 28 and 29 adapted to.
slide alongin their own planes and m parallelfip'aths to eflect'an opening and closing 10 oft e hatchway 2 at that landing; These doors 28 and 29 are preferably provided with operating arms, as shown. in the copending Shonnard application, Serial No. 216,808, filed September 1, 1927, now Patent 1,863,417,
issued June 14, 1932, above referred to, or tog 1e levers as they are commonly termed in t 0 art; In addition, a suitable device as for example the mechanism shown designated by reference characters 50 to 61 inclusive in Patent: No. 1,691,787 issued to Harold W.
Shonnard on November 13th, 1928,- on an application filed simultaneously withthis application is providedfor'transmitting every motion of the-gate 7 to the doors 28and 29 whenztherelevatorris stopped adjacent to the saiddoors.
The foregoingex anation is believed sulficienttor indicate t e nature of'one of the mechanismszto which'the invention claimed hereinis applicable. It remains to describe in detail the electrical" parts and connections invoked in .the'preaferredrembodimenhof this invention, withiparticular reference to Fig Referring to Figure 2-reference character 103! designates a relay used for-controlling theinitiationsofioperation of the elec primmmoverlfli Ala-shown in Figure 2by ably locatedwithin'the elevator. 1 in-such a:- position as to be normally closed while the operators controLIevenG; isinzeither running position; in? other words the circuit to'the relay 1035501089681 the points 105wand106' at allttimes while thecar is progressing-in normal maameralongthe hatchway 2in either direction, and so. flSrtO adapt the system to elelvatorsprovidedwith leveling? or grad-- ualsto p ng andistarti'ng means, the circuit throug the relay 103 preferably passes by means ofa parallel branch through a set of contacts 107 "and 108, these contacts being normally closed by 0 eration of relay 109 connected'in' parallel with the elevator hoisting motor armature Hi With this arrangement itwillb eohv'icus that the circuit through the relay 1U3fwil1 be closed by means of this branchcir-euitijust referred to so long as the hcisting metor armature H remains energized, and irrespective of any movement im parted to the-operators control lever 6for the purpose of bringing the :same to the new tral osition as a preparatory measure to stopping the elevator.
With control means arranged as just described it will be evident that, as the elevator approaches a floor where a. stop is to be made, as for example, the floor at which the doors 28 and 29 are located, the throwing of the elevator operators control lever 6 to the neutral position willh'ave'no eflect the continued energization of'the relay 193*ex- 7 cept to shunt the circuit passing-theretflrough to the branchineluding the contacts 107 and 108. After the decelerating circuits or other meals ovided for gmdually bringing the motor to a stop have operated in response to the-centering of the control lever '6, the resultantde-energizationof theirelay 1094mmmits the contaets'107 andi 108 to"= separate: thereby opening the *circuit1through therclayi. 103 and de-energizing saidrelay. 3
The de-energization ofrelay 103 which is; thus produced functions to close the 0mm- 112 and 113 upon each otherltlun'ehyclosing: a circuit to the relay 115.}this-cirm1itzpaming as follows :-from sideB ofiftln three a source of currcnt through conduwor llfiwom' tact-s 117 of -a protective circui-ttbrwkeri 118;. conductors 119 and 120, contacts113-Zamt112- conductors 121 and 122, switclpQLl (whiohn in the position of the gear29ias sllmmin closed) thence through oonductms 125. and 126 to the relay 115, thence back to side G off the source of "current thruittfie cond'ndion'lfilm. The energization ofrrelay thus produced functions to cause at closing'ofr the direetional switches 01, O2 and O3; and. also:
1 functions to cause the closing of the ccartmtr 04. The closing of the mutant; 04 thus brought about closes a,- circuit to the potential relay 130 passing from side Biotxtho It three phase line throughicondnetors: 116 andi 131, contact 04, relay 130, conductor 132, con-'- tact: 133, conductors 134- and 127 back .toside C of'the three phase line. The energi'zaticn; of the potential relay 130 thus brought about simultaneously with-the closingof: the comtacts O1, O2 and O3 aetstoclose the potential contacts PA, PB: and BG. Thea-closing of: the directional contacts 01,02famd-O3 and the potential contacts BA, PB'and'PC, thusefl'ected, produces an energization of thcz operating windings-offthe door'operating'motor 16. As shown herewith by way of illus-- tration, the motor is wound asaithreephasealternating current machine. Obviously 159 other types of electric prime-movers-may be utilized. The energization of thedoor op-- erating motor 16 thus brought; about causes a commencement of the opening'movement of the elevator gate, and-also, through the mechanical connections heretofore described,
a corresponding movement of the h'atchwaiydoors 28 and 29. Now astherotation of motor 16 brings the gear 20 to the predator-'- mincd point in the door-openingzmovementt the contacts CL are moved to closed position by action of the cam 24 previously described. The closing of the contacts CL thus brought about closes a circuit to energize the relay 140, this circuit passing as follows :from side 0 of the line through conductor 127, relay 140, conductor 141, switch CL, conductors 1 12 and 119 and switch 117 back to side B of the line. The energization of relay 140 thus produced serves to close the normally open contacts 140?) and to open the normally closed contacts 1 10a, but this opening of the contacts 1410a has no immediate effect on the circuit passing therethrough, for the reason that the circuit has previously been (lo-energized as a result of the opening of the contacts 05, the latter having opened upon the energization of relay 115 above described.
Now, as the continuing opening movement of the doors in response to the energization of the door operating motor 16 brings the gear 20 into position to open the contacts OL, this opening of the said contacts causes an opening of the circuit passing therethrough to the door opening relay 115, thereby dc-energizing the said relay. The deenergization of this relay 115 causes a dropping out of the directional contacts 01, O2 and 03, thereby de-energizing the motor windings. This de-energization of the relay 115 also serves to reopen the contact 04, thereby tie-energizing the relay 130. The dc-energization of relay 130 which is thus effected permits the contacts PA, PB and PC to again resume their open positions.
Immediate stopping of the motor, however, does not follow because of the momentum gathered by the rotating parts of the motor 16 while the motor was operating. This momentum is sufficient to carry the elevator gate and associated hatchway doors 28 and 29 to their full open positions.
Now, when it is desired to start the elevator away from this landing, and, pursuant to this intention, the operation of the elevator hoist-- ing mechanism is again initiated through the control lever 6, the consequent closing of the contacts 105 and 106 causes a return of t ie circuit through the relay 103. The energization of relay 103 which is thus effected permits the contacts 112 and 113 to open and the contacts 113 and 11a to resume their normal 1y closed condition. The closing of the coni tacts 113 and 114 thus brought about functions to complete the circuit passing through the previously closed contacts 1407) to the close relay 155. The completion of this circuit and the consequent energization of the relay 155 causes a closing of the directional tially as traced heretofore. The energization of relay 130 which is thus brought about serves to close the potential contacts PA, PB, and PC, thereby energizing the motor windings to cause rotation of the motor 16 in the reverse direction to that previously produced. The resulting rotation of the motor 16 causes the elevator and the associated doors to commence their movements toward closed position, and incidentally causes a corresponding rotation of the gear 20. When this rotation has proceeded the predetermined amount necessary to close the contacts 0L, the occurrence of this operation has no immediate eli'ect upon the circuit passing therethrough since the said circuit remains open at the contacts 112 and 113 as previously pointed out. The further rotation of the motor 16 and correspond rotation of the gear 20 causes, after the predetermined movement, an opening of the contacts CL. This opening of the contacts CL breaks the circuit to the relay 1 10, thereby opening the contacts 140?) and closing the contacts 1 10a. This opening of the contacts 14:05 breaks the circuit to the relay 155, as is plainly evident from the diagram of Figure 2 thereby permitting the directional switches C1, C2 and C3 to resume the open position, thereby breaking the path of current to the motor 16 which has heretofore passed through the contacts C1, C2 and C3 and permitting the cur rent to pass through the branch circuits including the contacts B1, B2 and B3, these latter contacts being closed at the same instant by the means presently to be lescribcd. Furthermore, this de-energization of the relay 155 permits the contacts C4 to separate thereby (lo-energizing the relay 130. This de-energization of relay 130 permits the potential contacts PA, PE and PC to open. At the same time the closing of the contacts 140a which was offected as above pointed out by the (lo-onergization of the relay 1 10 closes the circuit passing through the circuit relay 190, this circuit passing through the conductors 116 and 165, contact 140a and normally closed contact O5 to the relay 100, and thence back to the line by way of conductor 12?. The energization of relay 190 thus brought about serves to close the switches B1, B2 and B3. thereby maintaining the motor 16 energized, the energizing current passing through the branch circuits 166, 167 and 168, these branch circuits containing resistance units R1, and R3 for a purpose to be described.
The remaining portion of the door closing movement is effected thru the momentum gathered by the rotor, as in the case of the opening movement above referred to.
During this final stage of the door closing movement, and during the succeeding travel of the car from the landing at which the stop was made, and until the control means are again initiated to bring the car to a stop again the windings of the motor 16 remain energized through the branch circuits 166, 167 and 168 which were closed in a manner described above. This continued energization of the windings of the motor 16 creates an electric force in the door closing direction which constitutes a means for maintaining the elevator gate 7 firmly closed irrespective of any mechanical means which may be provided for this purpose. In order to prevent too great a consumption of power, however, during such normal running of the elevator, suitable resistances R1, R2 and R3 are inserted in these circuits to maintain the current at a reasonable amount.
The conditions last described prevail until the control lever 6 is again manipulated for the purpose of stopping the car at a succeeding landing. When this occurs the cycle of operations heretofore carried through is again inaugurated. In this connection it may be noted that the energization of the relay 115 which occurs in proper sequence following the return of the operators lever 6 to the neutral position, causes an opening of the contact ()5 as well as a closing of the contacts 01, O2, O3 and 04. This opening of the contact 05 brings about the de-energization of the relay 190 and the consequent reopening of the contacts B1, B2 and B3 thereby cutting oif the current normally flowing through the motor 16 while the elevator is in operation. This permits the subsequent energization of the motor 16 in the proper direction for opening the gate 7 and the associated landing doors.
Means may be and preferably are provided whereby continued energization of the windings of the motor for a period greater than a predetermined amount is prevented by virtue of an automatic circuit breaking mechanism. In the preferred arrangement, this automatic circuit breaking mechanism is constructed so as to operate upon the lapse of a predetermined time the amount of which may be adjusted to suit the circumstances and conditions of the installation. As shown herewith, this means comprises a timing relay TR connected in a circuit in series with one set of contacts on each of the directional switches O and C but having a shunt connection from the potential relay 130. The mechanism, furthermore, includes a constant speed motor TM adapted and electrically connected so as to be energized simultaneously with the energization of the timing relay TR. Associated with the motor TM is a circuit breaker 133 connected by suitable means (not shown) with the motor as to move in response to the movement of the motor, the position of the circuit breaker 133 being such that upon completing a predetermined amount of movement it arrives at its open position thereby breaking the circuit passing therethrough to the potential relgg 130 and a second circuit to the motor T With this arrangement, the closing of either set of directional switches preparatory to the energization of the door operating motor 16, causes current to flow through the timing relay TR and also causes the energization of the motor TM and consequent movement of the circuit breaker 133. When this movement has continued for the predetermined length of time the de-energization of the relay 130 occurs, thereby causing the potential contacts P to drop out, de-energizing the windings of the motor 16. With this arrangement the possibility of a burning out 81) of the motor windings is eliminated.
It is to be observed that with the control mechanism just described, it is possible by a manipulation of the control lever 6, to stop and reverse the direct-ion of rotation of the motor 16 at any point in its operation and at any point in the corresponding movement of the door. In this connection, it is to be noted that when a door is reversed during its travel in either direction and fails to complete its return movement after the reversal prior to the cut-off of potential contacts by the automatic cut-off mechanism, two methods are provided for effecting a completion of the return movement; one method consists of effecting a second reverse movement of the door through the principal control means, and this method, which results in a double reverse movement of the door before returning to its fully closed or fully open position, as the case may be, may be utilized in any event irrespective of the point at which the doors movement is interrupted by the automatic cut-oil mechanism.
The second method of completing the return movement concerns the use of the teaser buttons TBI and TB2. These buttons, which in effect constitute a second means of closing the switches CL and CL respectively, may be operated by the attendant in the car to complete the return movement of the door to either its fully opened or fully closed position, as the case may be, when the interruption of the doors movement occurs in either of the end zones; the end zones being the zones corresponding to the amount of movement which the gear 20 has after passing the contacts OL in the opening direction, and the contacts CL in the closing direction. On such occasions the operation of the proper teaser button causes a re-closing of the potential contacts and proper directional contacts to again energize the motor 16 and this energization will continue so long as the button remains pressed into circuit closing position or until a time interval has elapsed suflicient to cause the automatic cut-ofl' mechanism to again operate.
This feature is made possible by the provision of the branch circuits 181 and 182, the former being in shunt with switch OL, as indicated, and the latter being a second means for energizing the relay 155 to thereb close the directional contacts C1, C2, and 3, and the potential contacts PA, PE, PC, all of which close as a result of the energization of the said relay 155, as heretofore described in detail in connection with the primary method of closing the doors, to wit, through the conta ts 1401;. This secondary circuit to the relay 155which passes by Way of conductor 127, relay 155, conductors 179 and 182, switch T132, conductors 183 and 1.84, contacts 114 and 113, member 120, and conductors 119 and 116 back to the line-is in effect a shunt about the previously opened contacts 1406.
When it is desired to separate the door control means from the hoisting motor control means a separate device 203 (Figure 3) may be utilized for performing directly what is performed indirectly by the use of the contacts 105 to 106 and the relay 103 of Figure 2. Thus, referring to Figure 3, the means 203 is shown as directly controlling the contacts 212, 213 and 214, which may be compared in their function to the contacts 112, 113 and 114 of Figure 2. With this single change the diagram of Figure 3 is identical with that of Figure 2, and serves to illustrate one means by which the operator or attendant in the car may be given a separate control of the door motor energizing means in place of the more unified and more automatic control means of Figure 2.
The above specification and the annexed drawings are to be considered only as illustrative of what we deem the preferred embodiment at this time. The invention is not limited to this specific form or to any particular combination or application of the parts, but embraces all modified forms and constructions within the scope of the appended claims. Thus, for example, instead of employing a single prime mover mounted on the elevator separate power means may be provided at each landing, with the control means therefor either centered in the elevator or distributed at the various landings.
We claim:
1. In an elevator system, an elevator adapted to serve a plurality of floors, a door controlling access to the elevator at one of said floors, means for opening said door only when the elevator is adjacent thereto comprising an electric prime mover on the elevator, motion transmitting connections between said prime mover and the door to be opened, means for energizing said prime mover, means for de-energizing said prime mover at any point in the opening movement of the door, means for energizing said prime mover to cause movement thereof and of the connected door in the reverse direction, and time controlled means for cutting off the supply of energy to said last named means upon the lapse of a predetermined time interval.
2. In an elevator system, an elevator adapted to serve a plurality of floors, a door con trolling access to the elevator at one of said floors, means for opening said door only when the elevator is adjacent thereto comprising an electric prime mover on the elevator, motion transmitting connections between said prime mover and the door to be opened, means for energizing said prime mover, means for de-energizing said prime mover at any point in the opening movement of the door, and separate time controlled means for cutting off the supply of energy to the prime mover at a predetermined period after its energization, said means being operable at any point' in the movement of said door.
3. In an elevator system, an elevator adapted to serve a plurality of floors, a door controlling access to the elevator at one of said floors, means for operatingsaid door when the elevator is adjacent thereto comprising a prime mover, a motion transmitting connections between said prime mover and the door to be operated, means for energizing said prime mover to move said door through the instrumentality of said motion transmitting connections, means for de-energizing said prime mover when the door reaches a predetermined point in its opening movement, separate means operating prior to and concurrently with said last named means and capable of deenergizing said prime movor after the lapse of a predetermined length of time irrespective of the position of said door.
41. In an elevator system, an elevator adapted to serve a plurality of floors, a door controlling access to the elevator at one of said floors, means for opening said door when the elevator is adjacent thereto comprising a prime mover, a motion transmitting connect-ions between said prime mover and the door to be opened, control means within the elevator for controlling the energization of said prime mover, means for de-energizing said prime mover at a predetermined time after the operation of said control means, and auxiliary control means for producing a second energization of said prime mover after the operation of said de-energizing means.
5. As a sub-combination, an elevator door, a mechanism for opening said door, means within the elevator for controlling the energization of said mechanism, means for deenergizing said mechanism when the door reaches a predetermined position in its opening movement, and auxiliary means for again energizing said mechanism to move said door beyond said predetermined position.
6. As a sub-combination, an elevator door, means for operating said door comprising a prime mover and operating connections between said prime mover and said door, means within the elevator for controlling the energization of said rime mover comprising a control lever w ich in its normal or neutral position prevents energization of said prime mover, means for energizing said prime mover when said control lever is moved away from its neutral position, separate means for tie-energizing said prime mover, comprising a pair of mechanisms operating simultaneously but separately, one of said mechanisms operating in response to the movement of said prime mover to cut, oil the power fiow'in to said prime mover after a predetermine degree of movement thereof, and the. second de-energizin means 0 erating after the lapse of a pre etermine time interval to cut of the ower to said rime mover irrespective of t e operation 0 said first named de-energi'zing means, and means for preventing second energization of said prime mover until said control lever is retittrried to its neutral position.
Signed at Hoboken in the county of Esseii'and State of New 'ersey this 14th day of December; A. I). 1927.
HAROLD W. SHONNARD. HAROLD J. FEAR.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2552675A (en) * 1950-01-11 1951-05-15 Joseph L Hauflaire Coin control apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2552675A (en) * 1950-01-11 1951-05-15 Joseph L Hauflaire Coin control apparatus

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