US2003399A - Door operator - Google Patents

Description

J. C. TAMSITT DOOR OPERATOR June 4, 1935.

Fild May 2, 1952 1o sheets-sheet 1 J. C. TAMSITT DOOR OPERATOF JuneI 4, 1935.

Filed May 2, v1932 1o sheets-sheet 2 fake/wr.'

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Jne 4, 19,35. v y J. c *TAMslTT l 2,003,399

DooR OPERATOR Jia/2663676# l.

June 4, 1935. J. c. TAMslTT 2,003,399

DOOR OPERATOR JuneA 4, 1935.- l J. TAMslTT 2,003,399`

` DOOR OERTOR Filed May 2', 1952 1o sheets-sheet 5 4 iig@ h LA `lune 4, 1935.

J. C. TAMSITT DOOR OPERATOR Filed May 2, 1932 10 Sheet-Sheet 6 J. C. TAMSITT DOOR OPERATOR Julie 4, 1935.

Filed May 2, 1932 l0 Sheets-Sheet '7 .June 4, 1 935.' J C, TAMS@ r 2,003,399 V DOOR OPERATOR l Filed May`2, 1932 lO Sheets-Sheet 8 June 4, 1935. Y l.1. c. TAMslTT .2,003,399

DQQR OPERATOR Filed-'May 2, -.w52 1o sheets-sheet 9 June 4, 1935. 1 C, vTAMSlTT 2,003,399

DOOR OPERATOR Filed May 2, 1932 l() 'Sheets-Sheet l0 fm/en'or: JSep/f C Tama# Patented June 4, 1935 t t UNITED STATES PATENT OFFICE DOOR OPERATOR Joseph C. Tamsitt,y Aurora, Ill., asslgnor to Bichards-Wilcox Manufacturing Company, Aurora, Ill., a corporation of Illinois Application May 2, 1932, Serial No. 608,661 19 claims. (c1. 137-52) 'I'his invention relates to door operators. broughtl to rest. The door operator is stopped by Modern elevators frequently use a mechanism a limit switch when it is in such position that for automatically opening the hatchway doors the door is fully open. The door remains opened when the elevator is stopped at a oor level, and until further operation by the elevator operator for closing these doors prior to the restarting of at which time the carriage is moved in the oppo- 5 the elevator away -from that iloor. My present site direction, and as before the rst part of its invention provides a new and improved device movement may be checked so that the door and for accomplishing this purpose, a device which carriage are started gradually and without shock. is light in weight and therefore reduces the 'I'he nal movement of the door into its closed l0 deadweight load that`must be carried by the position is checked by a checking device and the 10 elevator. My invention also provides for a rapid door operator is stopped by a limit switch. opening and closing of the elevator door in a quiet The door operator of my invention is adapted and safe manner which includes checking its to be connected to the gate or door of the elevator movement at the ends of its path of travel, and cab, and to operate that gate simultaneously with lo further provides for the instantaneous release of an operation of the hatchway doors. Preferably '15' the door mechanism from the opening mechathis connection includes a safety release which nism in case the door strikes an obstruction, quickly detaches the cab gate from the carriage thereby eliminating the possibility of a passenger of the operator when the gate strikes a passenger, being pinned between the door and doorirame. 0r any obstruction which prevents its i'ree 2o In the preferred embodiment of my invention, movement. 20

a stationary rail is mounted upon the elevator My invention also includes the provision of an in a convenient location, such as for example at interlocking arrangement whereby movement of the top of the cab. 'I'iiis rail carries a power the elevator car away from the iloor level is imV driven carriage to which is pivoted a shoe o r possible until the hatchway door has been comoperating rod which is adapted to engage the pletely closed and latched. This prevents the 25 latching mechanism of the doors in the hatchpossibility of hatchway doors being left open way. Normally the shoe is in lsuch a position when the elevator is elsewhere inthe shaft. with respect to the latches that the car may be My invention will be best understood by referraised and lowered in the shaft without engaging ence to the accompanying drawings in which a the latches that it passes. preferred embodiment of it is shown by way of 30 When it is desired to stop the elevator at a parexample, and in which: ticular floor and open the hatchway doors at Figure 1 is an elevational view of the operator that floor, a control lever is operated to bring a mechanism located at the top of the elevator; range relay into its operating position. When Figure 2 is an end view of the mechanism the floor is approached a stationary cam in the shown in Figure 1; 35 hatchway engages with the range relay to render Figure 3 is a diagram illustrating the operathe door'operator operative when the elevator tion oi the door checking mechanism; has been brought to rest. As soon as the elevator Figure 4 is a cross -sectional view taken along stops the door operator mechanism is started a vertical plane through the longitudinal axis of j 40 and the carriage and shoe are moved into such a the door cheek mechanism; 40

position that the shoe engages the latching mech- Figurel 5 is a cross sectinl View of the door anism of the door and operates it rst to unlatch check mechanism taken along s horizontal plane the dOOl' and then t0 mOVe the dOOl' t0 its Open through the axislof the mechanism. position. i im] The initial movement of the carriage may be fpfleuviisn; innmt cargshscialcie; cheeked by a checking device, either mechanically l i taken su] I Il u ons the une or electrically so that it is brought up to its full speed gradually and the shoe is therefore brought s of' nwe 5 loom of the l l into engagement with the latching mechanism ma; f-

f and the movement of the door started without m9 .7 is a man View *0f 001' latch 50 abruptness and the operation therefore is quiet 31861181118!!! 5mm #hb operont shoe waged and safe. with it; y f

. door approaches `its open position a Figure 8 is a plan view of the door' latch mechanical checking device is engaged by the mechanism showing the operating mechanism in carriage and the door and carriage are gradually -itlnonnal position: 55

` latch;

feo

Figure 10 is a fragmentary cross sectional view taken along the line III-III of Figure 9 looking in the direction of the arrows;

Figure 11 is an end elevational view of the range relay in its normal position;

Figure 12 is a similar View of the range relay at the end of the flrst step of its operation;

Figure 13 is a fragmentary elevational view of the range relay at the end of the last step of its operation;

Figure 14 is a fragmentary plan View of the range relay mechanism;

Figure 15 is an elevational view showing the connection between the door operating mechanism and the cab gate of the elevator;

Figure 16 is a cross sectional view taken along the line I6-I6 of Figure 15 looking in the direction of the arrows;

Figure 17 is a plan view of a limit switch mechanism;

Figure 18 is a cross sectional view through the limit switch taken along the line I8-I8 of Figure 1'7 looking in the direction of the arrows;

Figure 19 is an elevational view of the interlocking contacts of the device;

Figure 20 is a schematic circuit diagram showing how the devices of my invention may be connected together electrically;

IFigure 21 is a planview of a modiiied form of operator;

Figure 22 is an end elevational v'iew of the operator shown in Figure 21;

Figure 23 is a front elevational view of the operator shown in Figures 21 and 22;

Figure 24 is an end elevational view of a modified form of latch and interlocking device applied to a hatchway door;

Figure 25 is a front elevational viewV of the latch and4 interlocking` device shown in Figure 24;

Figure 26 is a plan view of the latch and interlocking device shown in Figure 24vdrawn to an enlarged scale and showing also a modified form of latch operating shoe carried by the operator carriage, with the shoe in its normal position;

Figure 27 is a view similar to Figure. 26, showing the latch and shoe in their respective operated positions;

IFigure 28 is a cross sectional view of a sim-- plifled carriage checking device;

Figure 29 is a fragmentary view taken along the line 29-29 of Figure 28 looking in the direction of the arrows;

Figure 30 is a fragmentary -view taken along the line 30--30 of Figure 28 looking in the direction of the arrows;

Figure 31 is an elevational view of a modified form of cab gate operating device; and

Figure 32 is a plan view of the device shown in Figure 31.

Referring now to the drawings in more detail, particularly Figures 1 and 2, it will be seen that the door operating mechanism indicated generally at I is mounted on the top front edge of the cab 2 of the elevator, that is adjacent to the doors that are. to be operated by it.

This door operating mechanism consists of a suitable frame work 3 attached to the frame of the elevator 2 in any preferred manner. Obviously the specific details of the frame 3 and its manner' of attachment to the elevator will vary with the particular conditions met. and the spethereto by adjusting screws 5 and nuts 6 to permit a limited movement of the rail longitudinally.

Mounted upon thisrail is a carriage 1 to which is pivoted an operating shoe 8. This shoe is urged to rotate about its pivot 9 by springs II, which are disposed in a recess formed in the carriage 1, and have one end engaging the bottom wall of the recess and their other end engaging the shoe 8. A stop member I0, suitably secured to the carriage 1, extends upwardly in front of the shoe 8. The springs II serve to urge the shoe 8 forwardly about its pivot 9, as shown in Figure 8, and the stop member I9, abutting the forward edge of the shoe, limits such forward movement of the shoe. The purpose of the pivotal connection of the operating: shoe will be hereinafter explained. The top and bottom edges of the shoe 8 are bent inwardly toward the car as indicated at I2 for a purpose whichwill be hereinafter explained. The carriage 1, shoe 8, rail 4, and in fact the entire framework 3, may be conveniently made of iron or steel. If desired, bearing blocks I3 may be interposed between the fra-mework of the carriage 1 and the guide rail 4 to permit frictionless movement of the carriage upon this rail.

Mounted. upon the framework 3 are a pair of sprocket wheels I4 and I5 to one of which is connected a gear reduction mechanism I6 by means of a suitable coupling member I 1, Figure 2. This mechanism, indicated generally at I6, may be a series of spur gears or if desired a worm and gear speed reducing mechanismof any preferred type. A motor I8 connected to the speed reducing mechanism I5 drives that mechanism and in turn rotates the sprocket wheels I4 and I5. A suitable chain I9 is attached at its opposite ends 20 to the carriage 1 by means of an adjustable connection indicated generally at 2I and preferably comprising a bolt attached to th'e end of the: chain and projecting through a member on the carriage and nuts threaded upon the projecting end of the bolt. Obviously any other preferred arrangement for attaching and tightening the chain I9 may be provided within the teachings of my invention. The chain I9 is threaded over the sprocket wheels as shown.

The carriage 1 is moved by the motor I8 through its rotation of the sprocket wheels Il and I5 in the obvious manner. A lubricating means 22 may be provided to lubricate the rail l so that the carriage 1 may be moved over it quickly and quietly.

Mounted upon the frame 3 are checking devices 25 and 28, which operate to retard the movement of the carriage 1 as it approaches its limit positions.

As will be seen in Figures l, 3, 4, 5 and 6, the retard devices 25 and 26 comprise a shaft 21 journaled for oscillation about a substantially horizontal axis. Mounted upon this shaft is an arm 28 the lower end of which extends down into the path of rollers 29 and 30 carried by a plate 3| on the cab side of the carriage 1. The opposite.

1 moves in the opposite direction, the roller 3B engages the opposite side of the arm 28 and rotates that arm in a counterclockwise direction about the axis of its shaft 21. When the arm is in either one of its limit positions the counterweight 32 is past center and therefore tends to rotate the arm further in the direction in which it was moved to reach that limit position. This insures that the arm will remain in place when it is in either of its limit positions.

The shaft 21 is journaled into the body 33 of the checking mechanism, and a bell crank 34 is rigidly attached to the end of that shaft within the mechanism. A cylinder 35 is also located in the body 33 of the mechanism, that cylinder being closed by a suitable plug 36 and sealed by a gasket 31. Located within the cylinder 35 is a piston 38` which comprises two sections and 40 located upon its opposite ends. Carried Within the piston 38 and engaging the end of the bell crank 34 is a pusher plate 4| which ts within a recess 42 in the piston and is held against the bell crank 34 by a spring 43. The opposite end of this spring ts against the valve seat 44 which contains a ball valve 45 that is maintained upon its seat by a spring 45.

The opposite end of the piston contains pusher plate 41 which also bears against the bell crank 34 and projects into a pocket 48 in that end of the piston. 'I'his pocket is closed by a valve 48 which is retained on its seat by a coil spring 58.

Leading out of the end 5| of the cylinder 35 is a by-pass passage 52 which is normally closed by a valve mechanism 53 held on its seat by a spring 54. The tension of this spring is adjusted by a stud screw 55 threaded into the plug 55 by which the valve chamber 51 is closed. Suitable packing means 58 prevents leakage of iiuid around this stud screw 55. Leading out of the valve chamber 51 is a port 58 which communicates with a second by-pass passageway 68 that opens through a port 5| into the opposite end 82 of the cylinder 35. The by-pass passageway 60 also leads to a valve 83 which is maintained upon its seat by a spring 64, the tension of which is adjusted by a stud screw 85 threaded into the plug 56 by which the valve chamber 61 is closed. Suitable packing means 83 are similarly provided to prevent leakage of fluid around this stud screw.

'I'he valve 53 is provided with an opening 69 into which a reduced portion 10 of the stud screw t85 projects, that projection serving also as a'guide for the valve. The valve 5! contains a leakage port 83 which is partially covered by the end of the reduced portion 10 of the screw 85 to regulate the amount of leakage through this port.

The valve chamber 81 opens through port 1I shaft 21 is rotated in a clockwise direction, lig-` ure 5, the bell crank 34 pushes the pusher plate 4I against the tension of spring 42 and as the motion is continued the piston 38 is moved to the right. Oil in the end section 3|;of the cylinder is thus placed under pressure Vand forced through the by-pass pamageway 52 where it engages the valve 53. The liquid also flows through the port 1| intoth'e valve chamber 61 and a small" y quantity of it leaks through the opening inthe valve 88 into which the projection 10 of ythe stud more rmly seated upon its seat by pressure built up in the valve chamber 61. A small quantity of uid leaks out of chamber 51 through the port 63. 'Ihe pressure in the passageway 52 overcomes the tension of spring 54 and raises the valve 53 off of its seat, permitting the oil to flow into the valve chamber 51 and out of it through the port 59 into the passageway 60 and through the port 6| into the end section 82 of the cylinder. Since the piston 38 is moving to the right the chamber 62 will be increasing in volume so that there will be ample room for the oil received by it.

When motion in the opposite direction is started bell crank 34 moves against the pusher plate 41 and moves that plateinto the chamber 48 against the pressure of oil contained in that chamber. If this pressure builds up sulliciently shigh, valve 49,is seated against the tension of spring 58 andthe oil may escape into the end section 62 of the cylinder ahead of the moving piston. As the piston moves to the left, oil is forced out of the end 52 through the port 6| and passageway B0, against the surface of valve 63 and through the opening 69 of that valve into the valve chamber'51. Since the opening is small the pressurewill overcome the tension of spring 64 and lift the valve 63 off of its seat permitting rapid escape of oil from the passageway 60 into the valve chamber 61 from which it escapes l through the port 1| into the passageway 52 and back into the end 5| of the cylinder behind the retreating piston. Obviously this oil in the passageway 60 may also flow through the port 59 into the valve chamber 51 where it is obstructed by the valve 53 which is now closed.

The spring 51 is made considerably stronger than the spring 64 and consequently the valve 53 will be maintained upon its seat untila higher pressure is built up behind it than will the valve 53. The checking arrangement is therefore capable of producing a greater retarding effect when its shaft 21 is rotated in one direction than it is when it is rotated in the opposite direction. Preferably the device is mounted in such a manner that as viewed in Figure 4 the piston will move to the right when the carriage 1 is 'being brought to rest at the end of its travel'from oneof its extreme positions to the other, and the piston 38 will move to the left when the movement of carriage 1 is being started. By this arrangement a small opposition is afforded to the starting of the movement of carriage 1 and the carriage is therefore accelerated gradually, and a greater opposition is met when the carriage is being brought to rest and it is therefore decelerated quite rapidly. Since the pusher plate 4| is spring mounted with respect to the piston 38 the piston is gradually brought up to speed when the roller 29 engages the arm 28, and the application of the checking is therefore somewhat gradual and can be made without imparting a jar or shock to the door mechanism moved by the moving carriage. Mounted upon the framework 3 of the door owator are limit switches 80 and 3l which are connected to the operating arms of the door checks 25 and 23 respectively. The details .of these limit switches will be found in Figures 17 and 18. It will be seen that each switch comprises a base 82 preferably composed of an insulating material such as hard rubber or a phenol condensation product, upon which is mounted a pair of brackets 83 in which is journaled a shaft 84 located at some distance above the upper surface of the base plate 82. The brackets 83 may be surrounded by insulating sleeves 83.

Mounted upon this shaft 84 are cams 85 and 86, and a bell crank 81 the free end of which is connected to a tie rod 88 which in turn is connec'ted to the operating lever 28 of the checking device. Thus it will be seen that amovement of the operating lever of the checking device will rotate the shaft 84 and the cams 85 and 86 carried by it. A

Mounted upon the base of the limit switch is a contact means 89 containing a movable contact 90 and a stationary contact 9| which are properly maintained and operated by spring 91 which raises the camming lever 93 upon which the movable contact 90 is mounted. This camming lever engages the cam 86 carried by the shaft 84 and when the valley portion of that cam is engaging the operating lever 93, the contacts 90 and 9| are opened. When the hill 86 of the cam engages the lever 93 that lever and the contact 90 carried by it are rotated about the pivot 94 to bring the contact 90 into engagement with the stationary contact 9|. The details of construction of this switching arrangement are more fully disclosed in my copending application Serial No. 607,688, led April 27, 1932, to which application reference is here made for those details. 'Ihe stationary contact 9| is projected through the base 82 and provided with nuts 95 by means of which a suitable wire, not shown, may be connected to the contact. Other terminals 964 are provided, each consisting of a screw projected through the base plate 82 and provided with nuts by which it is held in place on the base plate and by which wires are attached to it. The contacts 98 and 9| of the limitswitches are connected in the electrical circuit to bring the motor I8 to rest when the carriage 1 reaches its limit position and operates the checking device into the position shown in dotted lines in Figure 3. Obviously when the carriage is moved out of this position the shaft 84 will be rotated in an opposite direction and contacts -90 and 9| will again be opened by the spring 91.

When the elevator is being moved up or down in its shaft the carriage 1 will be disposed at one end of its trackway 4, corresponding to the closed position of the d oors of the hatchway. 'I'he doors will be locked in position/ by a latching mecha- Anism, such as'is shown in Figures 7, 8, 9, and 10.

This mechanism consists o f a plate mounted upon the door |0| in any preferred manner, such as by bolts |02. The door in turn is mounted upon a stationary trackway |03 by suitable rollers, not

shown'.

The plate |00 contains an extension |04 upon which is mounted a mounting bracket by means of bolts |06 projecting through slots, not shown, in the extension |04 of the plate |00 to permit a hunted lateral adjustment of the mounting bracket |05 in and out of the plane of the plate |80.

Carried upon this mounting bracket |05 is a pivot shaft |01 upon which is pivoted a lever |08 "which is held in place thereon by a nut |09 threaded onto the end of the pivot shaft |01. A spring. I0 attached at one of its ends to the `lever |08 at its other end to a portion of the mounting bracket 05 is tensioned to rotate the lever |08 in a clockwise direction, Figure 8, about its pivotal axis |01. into the position in which it is shown in Figure 8.

The lever |08 contains a generally rectangular recess bounded by projecting members ||2 and ||3. Preferably resilient inserts ||4 and ||5 are set in these projections and held in there in any convenient manner such as by rivets ||6. These inserts may be of a phenol condensation product, hard rubber, or fiber, as desired.

The lever 08 also contains a projecting lug i |1 which engages a latch ||8 that is pivoted at ||9 to a portion of the mounting bracket |05. 'Ihe free end of this latch contains a pawl which engages with stationary detent |2| mounted upon the carrier rail |03 in the elevator shaftway. With the pawl |20 of the latch lever I8 engaged with one of these detents |2|, the door |0| is securely latched in its closed position.

The latch mechanism is shown in Figure 8 with the pawl |20 engaged with a detent |2| and with the door closed. The carriage 1 is shown in the position in which it is placed when the elevator is moving upwardly or downwardly in its shaft. Itwill be noted that the shoe 8 lies adjacent to but does not engage the projection |3 of the lever |08. The elevator therefore is free to move upwardly and downwardly without obstruction from the latches on the doors in the hatchway. If the carriage 1 becomes dislocated or one ofthe latches is out of place, and the shoe 8 engages with the projection ||3 of that latch, or with some other projecting part of it, because of the tapered ends |2 of that shoe, it will be rotated in a clockwise direction, Figure 8,- about its' pivot 9 against the tension of spring so that the shoe may pass the obstruction without breaking either itself or the latching lever |08. When the carriage 1 is moved to the right to unlatch and open the door, the shoe 8 engages the resilient block ||5 located in the projection |3 and bears against that block to rotate the lever 08 in a counterclockwise direction about its pivot |01 against the tension of spring |24. This brings the shoe into the recess in the lever |08, that is between the resilient blocks ||4 and ||5. Since the shoe 8 engages the resilient block when it is brought into contact with the lever |08 the engagement is made without excessive noise, which obviously is advantageous.

It will be noted that the projection ||1 of the lever |08 normally rests in a recess |25 in the bottom of the latch I8, and obviously when the lever |08 is rotated in a counter clockwise direction and the free end of the projection |01 is moved to the left, it will ride up over the boundary of this recess and lift the latch into the position into which it is shown in the dotted line in Figure 9. This releases the pawl |2| and thereby unlatches the door.

The mounting bracket |05 upon which the lever |08 is mounted contains a resilient insert |26 against which the end of the lever |08 comes to rest when it is rotated inl a counter clockwise direction about its pivot. This block is resilient, the lever comes to rest without shock. Similarly, a resilient block |21 is provided on the opposite side of the mounting bracket |05 and the lever |08 comes to rest against this block when it is rotated by the spring H0, as will presently appear.

As the movement of the carriage 1 continues the shoe 8 bears against the resilient lock |5 and moves the lever *08 in a translatory motion carrying with it the door I0 which is thus opened.

Cir

When the door is practically completely opened the carriage l engages the checking device 26, and its motion is therefore retarded down, and the motion of the door mi is decreased gradually and it is brought to rest Without shock.

The shaft ll upon which the lever Hi8 is mounted is provided with a depression or groove t28 into which the tip end of the plunger 29 lits when the lever Iii is rotated against the resilient block llt. A spring i3@ tted around the shalt I3! of the plunger and held under tension Foy a plug 1132 urges the plunger H29 into the groove S28 and thereby locks the lever W8 in its operated position in which it is shown in Figure '1, against the tension of spring itt. This insures that the lever will be maintained in its engaging position with respect to the shoe i3 during the normal operation or" the device in moving the door iti.

When the motion of the carriage l is reversed the shoe t bears against the utloclr lid and moves the door it in the opposite direction towards its closed position. Should the door strike an ol:- stacle which olostructs its oath and prevents it closing, the tension placed upon the oloclr it by the shoe il will overcome the forces lochthe lever it@ in its operatedl position and that lever Will swing inte the position into which it is shown in Figure il to clear itself from tne operatshoe r'his clears the door from the operat mechanism, Whose carriage l continues to f eve to its entrer-ne position, and the door is then manually closed after the obstruction "nas hee removed ed to normal position in which it is in uigure 9, .il movement or? the lever lilT in cloclrr se direction about its pivot lill moves i projection ill haci?. into the recess latch ll' and that latch therefore t Ae door in its closed position. 2"; will he noted-that when the lever de 'c" es from the shoe to release the door 'from "ne operator because it encountered an oh- -uctio; the shoe and lever assume the posiu on shown in Figure 8, except oi? course that the latch l lil not engaged with the keeper lili and the shoe may loe farther from the lever 'When the door is closed latched inmually the operator is capable reoperating it with out the performance of any resetting omrations. The saine is true ii the door is not closed manually, `out is lei't in an intermediate position, that is neither open nor closed. The resetting is automatic in all instances and this arrangement is advantageous for many reasons. The auton matic reset obviously reduces the time lost by a release or the door from the operator as above explained.

Frequently elevator cales are provided with a gate or door which must he closed before the car can he moved. lf desired the carriage 'l may be provided with a projecting rod it@ which extends downwardly outside of the cab and engages with a plate Ml located on such inner door. This plaie preferably consists of a generally U-shaped bracket containing a socket i742 into which the lower end of the rod 40 is positioned. A spring pressed detent H3 registers with a groove M4 in the end of the rod E40 and serves to hold the rod in the pocket and consequently in engagement with the gate or door of the elevator cab. The plate Ml is so located upon the cab door that the rod M is moving to the left, Figure 17, when the door of the cab is being closed. Obviouslydif the door or gate of the cab comes into contact with a passenger or with any thing thatl tends to obstruct its free movement,

'the rod ma will te pulled out or the socket u2 and the gate will therefore be stoppeda The carriage l will of course continue to its normal position as if nothing had happened. By this arrangement, the gate as well as the hatchway door may oe closed by door operator with the lull assurance that passenger in the elevator 'will not be injured by accidentally coming into con= tact with the moving gate. The engagement of the rod Mil with the cao gate is reestablished by a movement of the rod to the right, Figure 16, or of the gate and plate lill to the left, this resetting obviously being automatic as the gate is closed.

It is generally most desirable in a device of this kind to provide an arrangement for prevent ing the door operator from functioning if the elevater is not properly aligned with the door level., Usually the elevator must be within two or three inches oi the door in order for the operator to function.. To this end l have provided an in@n proved range relay shown inli'igures ll, l2, i3 and ld which is connected into the control cir cuit of the door opera r in such a manner as to prevent its functioning untll the elevator brought within the presented distance ort the door level.

This range relay comprises a hase it@ prefere' ably made oi an insulating material such as a phenol condensation product or hard ru'eher, and upon which are mounted journal posts itil and 352., Two solostantlallgy parallel shafts l@ and ill are ,iournaled in these posts iol and Mounted on the shaft tot is an armature condensed of magnetic material and registering the coil or an electromegnet i577 which is mounted upon the lease .d suitable liaclr stojo lill?) is mounted unen this electroniagnet and serves as support for the armatore when it .is in its normal position, in Winch it is shown in Figure ll.

'Foe shaft itil also carries a block-lilac member l upon which is mounted a lever l d@ projecting nerven alongside the armature lli. il contact bracket let is also mounted upon this block alongside the mernher itil.

The shaft carries a lever Sti upon which is mounted a pin i553 around which is a coil spring ltd. "lisis pin projects 'through a perforation in the lever it@ and is locked therein in any preferred manner, such as, for example, by means of a cotter sin ite. The head oi the pin Het hears against the opposite face of the lever tot. Attached to this lever itt) is an insulating member to which carries a contact Htl which is thereby Aheld in substantial alignment with a contact it@ carried ty the contact arm tti o the shaft tt.

The shaft H53 projects beyond the journal posts itil and 52 and a camming lever H59 is mounted upon the projecting end of this shaft in any 1ereI ferred manner suchas by the set screw llt. The free end oi this camming lever i6@ carries a roller lll which is adapted to engage with sta-v tionary cams such as 12 located in the elevator.: shaft, as will presently appear,

Normally the range relay mechanism assumes the position in which it is -shown .in Figure '11, and the camming lever |60 is positioned with respect to the base i5!) in such a manner that it does not engage with the cams |12 as the elevator is moving in the shaft. When it is desired to stop at a Aparticular floor, a control lever in the cab is operated and the electromagnet |51 is energized. Thismagnet attracts the armature causing the shaft |54 to rotate in a counterclockwise direction into the position in which it is shown in Figure 12. The lever |60 pushes against the spring |64 and the shaft |53 is rota-ted thereby to move the free end of the camming lever |69 outwardly from the base |50 into such position that it will strike against the cam |12 when the elevator reaches the proper position in the shaft.

As soon as the roller 1| engages the cam |12 shaft |53 is rotated in a clockwise direction and the contact |61 carriedthereby is brought into engagement with the contact |66 carried by the shaft |54. 'I'he electrical circuit of the elevator operator is extended through these contacts and rendered operative when these contacts |61 and |68 are closed, so that the door operator may function to open the door in the hereinbefore explained manner. As shown, contacts |61 and |68 are spring mounted upon their respective levers so that they are capable of considerable movement toward each other and when engaged are put under considerable tension by their springs so that a good electrical contact is assured. The contacts slide with respect to each other upon being engaged and are therefore self cleaning. When the magnet |51 is deenergized the armature falls back into the position in which it is shown in Figure 11 and contacts |61 and |68 are separated by the tension in springs |64.

After an elevator stops at a particular floor and the doors have been opened, it is important that the elevator is not started until those doors are again completely closed and latched. This may be accomplished by placing a switch upon the guide rail |03 of the door and mounting a camming block |8| upon the door itself. Obviously, as the camming block is moved into engagement with the spring |82 of the switch |80 it will operate that switch and close an electrical circuit through itv which circuit can be utilized to control the starting of the elevator. Switch |80 may conveniently be a switch of the typemore fully disclosed in my copending application, hereinbefore referred to.

Furthermore it is important that the elevator be held at the floor level until the door operating mechanism returns to its normal position, to guard against the possibility of the operating shoe 8 striking an obstacle as the car is moved. To this endya switch |83 operated by the cam 85 of the limit switch assembly hereinbefore referred to can be and preferably is included in the control circuit of the elevator motor, so that motor cannot be started until the door operating mechanism is in ,its normal position.

In Figure 20 I have shown a representative circuit diagram illustrating by the usual circuit symbols one manner in which the devices of my invention may be connected together electrically in conjunction with the control apparatus of the elevator. This circuit diagram is shown by way 'of example only as there are many other circuit arrangements which may equally well be used to connect the devices of my invention into an operative system.

Referring now tofFigure 20 in more detail, the elevator hoisting equipment comprises the elevator hoisting motor 320, the elevator direction switches 32| and 322switch 32| containing Contacts 323 and 324 for governing the upward movement of the elevator, and switch 322 containing contacts 325 and 326 for governing the downward movement of the elevator, the relays 321 and 432|) for operating the switches 32| and 322, respectively, the door interlock contacts 329, of which there is one disposed on each hatchway door on each floor, the hoisting motor brake 330, which is shown, for example, as of the common spring applied electromagnetically released type, and the car switch 33|, which is mounted in the elevator and is adapted to operate the up and down contacts or switches 332 and 333, re-

s'pectively. When the, elevator operator desires to move the elevator in an upward direction, he rotates car switch 33|, thereby closing contact 332. A circuit may now be traced from line conductor 2|1, through the interlock contacts 329, through the motor brake 330, through contact 332 of car switch 33|, through relay 321 and thence to line conductor 2| 6. The motor brake 330 is energized and thereby released from its applied position over this circuit, and the relay 321 is energized over this circuit to close switch 32| against contacts 323 and 324. A circuit may now be traced from line conductor 2|'|, through contact 324 to the hoisting motor 320, and from hoisting motor 320 to contact 323 andA thence to line conductor 2|6. 'I'he hoisting motor will be operative over this circuit to vraise the elevator. Likewise, when it is desired to move the elevator downwardly, the car switch 33| is rotated to close contact 333. A circuit may now be traced from line conductor 2| 1, through the interlock contacts 329, through the motor brake 330, through contact 333 of car switch 33|, through relay 328, and thence to line conductor 2| 6. The motor brake 330 is energized and thereby released from its applied position over this circuit, and the relay 328 is energized to close switch 322 against contacts 325 and 326. A circuit may now be traced from line conductor 2|1, through contact 326, to the hoisting motor 320, and from the hoistingv motor 320 to contact 325, and thence to line conductor 2|6. It will be observed that the application of voltage across line conductorsv 2|6-2|1 is in the opposite direction to what it was when the elevator was being raised, and the motor will therefore operate in the opposite direction over this circuit to lower the elevator.

It will be noted that as the interlock contacts 329 are included in the circuits of the relays 321 and 328, that these contacts must be closed in order that the relays may be energized to close the direction switches 32| and 322. The opening and closing of contacts 329 are controlled by the hatch-way doors, and these doors must all be closed in order that the relay circuits may be energized. If one-of the doors is open, the relay circuits will likewise be open and consequently the brake motor cannot be energized to release the brake from its applied position, nor can the direction switches 32| and 322 be closed. The elevator, therefore, cannot be started until the door is completely closed and latched.

Referring now in more detail to the door controlling equipment shown in Figure 20, the apparatus to the left of the dotted line may conveniently be located on the elevator control panel, which frequently is located in the pent house at the. top of the elevator shaft. This equipment paratus also comprises a shut relay 2M containing contacts 202 and 20,3 and a second pair of contacts 294 and 205 which are operated to their respective closed positions when the magnet of the shut relay 2M is energized.v

The control equipment also comprises an open relay 2li@ which contains two pairs of contacts 207 and tot and 289 and 2lb, which contacts are closed when the winding of the relay c is energized. The control equipment also comprises an interlocking relay lil which controls a single pole, double throw switch comprising contact E l2 which engages with Contact M3 when it is in its normal position with the winding oi relay 2li fle-energized, and a contact 2id which is engaged hy the contact 2i? when the winding oi relay 2l i is energized.

Relays Titi, tot and 2li may he varied in roechanical design within the teachings of my invention and the mechanical details of them have therefore heen omitted. There are a number of relays commercially available which may he used in the circuit shown.

The common control equipment also consists of a pair of contacts which are closed when the main loralre ci the elevatormotor 2@ is applied.

Line terminals tit, lil and itt are connected to individual terminal lugs on the terminal bloei: Ztl). i cahle, indicated generally at f liQ, con-11 nects the terminal hloclr it@ to a second terminal block it@ carried hy the elevator. This cable may he oi any preferred design and construction the teachings of my invention.

The terminal lolocir contains a plurality ol individual contacts to which 'the conductors oi the cable iii@ are connected and also to which the wires leading to the various instrurnentalin ties carried hy the elevator are likewise connected.

The rector it, hy which the door operator rocch=- anisrn is actuated, contains three terminals 223,

and through which the motor is actuated to operate 'in either one ci two directions. 'The range relay, illustre-ted in ll'iguresl'i to le, inclusive, has its magnet iol connected to terminals from the terminal hloci; Pill@ and the contaots lilil and itil controlled by this range relay are similarly connected. The open limit switch contacts il@ and @i and the shut limit switch contacts Sil' and t: are likewise connected to the terminal hlcclr A pair oi eruriliary conn1 tacts and are included in the control mechanism oi' the elevator to 'oe closed "oy the car switch Sti when that switch is moved to start the car either an upward or a downward direction. When the control mechanism oi the elevator is in its normal position, that is with the main motor ci the elevator idle, these contacts and 225 are opened.

Assuming now that theA elevator is standing et a door level and that the hatchway door is open. rihe open limit switch comprising contacts and ti will he positioned so that these lcontacts areopened. When the elevator operator desires to close the hatchway doors and .start the car, he operates the elevator car switch 33t to close contacts 225 and 225. l

A circuit may now he traced from line conductor 2th to contacts L-l and M--S in the terminal strip 2410,l through the cable lIS to terminal CS-2 in the terminal block 200, thence through the contacts 224 and 225 to the terminal CS-i, through the cablevZlQ, through the terminal CS, through the winding of interlock relay 2l I, .and thence back through the L-I contact of the terminal block 2.0 to the line conductor ZIB. This energizes the interlocking relay 2l I, which closes contact 2I2 against contact 2 I4 and opens it away from contact ZIB. A circuit may now be traced from the line conductor 2I6 to the L-I terminal block and contacts M2 and 2M, through the winding of relay 20M, through the SL contacts of terminal-blocks 2li@ and 220, through the shut limit contact 90' and ti', and thence through the line conductor 2id through the terminal LC in the block 722i) and terminals lill-3 and L-S in the block 2ML The shut relay till energizes over this circuit and closes contact itt against contact 2te and contact 2532 against contact 263. A circuit to the motor i8 may now he traced from line conductor 2i@ through contacts 2M and 2th, through lvl-2 contact oiterminal block mit, through the cable lill to the itiil terminal block 22h, thence through the terminal 225 of the motor, through that motor and the terminal tt, through the neutral line conductor liti over the previously traced circuit. .t secn ond circuit to the motor :may alsohe traced from the line conductor lill through closed contacts tot and il, through the M-i terminals in hlocks itil and 22e, to the terminal of the motor. Motor it is energized over this circuit and revolves in such a direction as to move the carriage i to close the doors ci the hatchway. When the door reaches its limit position the shut limit contacts Qt .and i are opened whereupon the circuit ci relay lill is opened and that relay 'falls hack to open contacts tilt and ich and 8d2 'and 2t@ and thereby bring the motor il? to rest. The operator then actustes the car switch 33t in the elevator to open contacts 22 and 2% and to closethe contacts or 333 through which the movement of the elevator is controlled, and the elevator moves away from the floor which it was stopped.

When 'the elevator is moving toward the licor at which it is to stou and at whichthe hatch= way doors are to be opened, contacts Z225 and 226i are onen. The motive power ci' vthe elevator is turned o, hy rotating the car switch itil to the position shown in Figure 20, thereby open ing the contact or 333, whichever one may have heen closed, and deenergizing its associated relay circuit and opening the car direction switch. Beenergiratio'n o1 this relay circuit will cause the motor hralre t3@ to be applied and contacts iii@ controlled, thereby will ice closed. Upon the closing ci these contacts, a circuit may be traced from line conductor 2i@ through contacts il and 293 which are now closed, through the brake contacts lit, through the terminals R of the terminal blocks 2li@ and 2id, through the wind= ing itl oi the range relay, through the open lirnit contacts t@ and QI, which will be closed because the carriage l of the operator is in the position corresponding to the closed positions of the doors, and thence back to the line conductor 2id through the Contact LC of the terminal block 22u and the contacts 1.--3 and lvl-3 of the terminal hlock 250. Range relay is energized over this circuit and its camming lever 69 projected outward into position to engage the cam i12 located adjacent to the floor at which the doors are to be opened. When the cam i12 is engaged contacts I6? and IBS are closed and the open relay 208 is energized over a circuit traceable from a junction of the previously traced circuitv from line conductor 2l@ through the brake contact 2I5, vthrough the windingof relay 206, through the contacts RC in the ter- .to open that door.

minal blocks 200 and 220, through contacts |61 and |08, through terminal BL in terminal block 220 to the cut-out switch, from the cut-out switch through open limit contacts ,90 and 8|, to the line conductor 2|8 over the previously traced circuit. It may here be stated that the cut-out switch is normally closed, but if it is desired to prevent operation of the automatic door operator, the switch is opened. Relay 206 energizes over this last mentioned circuit and closes the contact 200 against the contact 2I0 and the contact 201 against the contact 208 thereby completing a circuit to the motor |8 which is traceable from the line conductor 2|6 through contacts 208 and 2I0 and thence through the terminal blocks and cable to terminal 223 of the motor. A second circuit to the motor is closed from line conductor 2|1 through contacts 201 and 208 and then through the terminal 22| through the terminal. blocks -200 and 220 and the cable 2|9. The circuit from the line conductor 2|8 to the terminal 222 remains closed, as before. It will be observed that the application of voltage across the line conductors 2|6|1 and |8 is in the opposite direction to what it was before, and the motor will therefore operate in the opposite direction and move the carriage 1 in such direction as to engage the latching mechanism of the door and When the door reaches its open position, open limit contacts 80 and 9| are opened, the relay 206 falls back, and the circuit to the motor I8 is brokenv and that motor comes to rest.

Thus it will be seen that the foregoing circuit connections may be used to connect the instrumentalities of my invention into a single completesystem for automatically opening and closing the doors of an elevator or similar structure responsive to the actuation of a single control g lever located within easy reach of. the elevator operator. The foregoing circuit is but one of the many which may be used for this purpose, and I do not wish to be limited to the precise circuit details which are shown by Way of example.

The devices hereinbefore described may be advantageously modified to meet particular conditions Within the teachings of my invention. In Figures 21, 22 and 23 I have shown a modified form of operator unit which in certain instances can be used advantageously over the unit shown in Figure l. It will be seen that the modified form of operator comprises a suitable framework 3 which is similar to the previously described framework and carries the rail 4 upon which the operator carriage is mounted. The carriage 1' carries the operator bar 8 which is mounted in a slightly different manner so that it is normally retracted into closer relation with the carrlage 1'. 'I'his arrangement permits the operatcr to be used in hatchways where the clearance between the ca r and the hatchway wall may be too small to permit satisfactory operation o f the device shown in Figure 1, since the operator arm 8' is retracted into the operator mechanism when the elevator is in motion and less clearance space between the car and the elevator hatchway is required. y

The kcarriage 1 is operated by chain Il which is threaded over sprocket wheels I4' and |5, as before. Sprocket wheel I5 is driven from a gear driven by a motor |8' through the speedreducing mechanism I6. 'This mechanism is connected to the shaft upon which the sprocket wheel I5 is ymounted by a suitable chain '280 threaded over a sprocket wheel carried by the speed reducing mechanism shaft 23| and also threaded over a sprocket wheel 232 carried on the shaft upon which sprocket I5 is mounted.

The operator shown in Figures 21 to 23 inclusive, further differs from'the previously explained unit in that the motor, speed reducing mechanism, and carriage operating mechanism are all carried as a unit upon the frame work 3'. To this end a platform like frame 238 is supported upon the main frame work 3 by suitable brackets 234 and serves as a mounting base for receiving the motor and speed reducing mechanism. The unit thus formed can be installed upon the elevator with a minimum of labor. The arrangement is further advantageous in that the operating mechanism of the operator may be covered Iby a suitable cover 235 detachably mounted upon suitable posts 236 carried by the mounting base of the unit. Such a cover will obviously protect the working parts from dust and dirt.

In Figures 21 to 23, inclusive, I have shown checking devices 25' and 26' which are of a slightly different type than the devices 25 and 26 hereinbefore explained. 'I'hese devices 25' and 26' are single acting checks which serve to bring the operator mechanism to rest, as will hereinafter appear. The checking devices 25 and 26 may also be used in the mechanism shown in Figure 1 should it be desirable to do so. These checking devices are operated by arms 28', as before, and limit switches and 8| are connected to these arms. It will be noted that these limit switches are mounted close' together and nea-r the center of the mechanism, in which position they may be conveniently covered by a separate cover should it be desirable to do so.

In Figures 23, 26 and 27, I have shown a modified form of latch and keeper, and have also shown the details of the mounting of the operator bar 8 on the carriage. It will be seen that the operator bar 8 is a vertically disposed member having beveled ends, as before, and is carried upon two horizontally disposed arms 240 and 24| which are pivoted to the carriage 1' by suitable pivots 242. A projection 243 of the arm 240 extends beyond the vertical bar 8 and is pivotally connected to a spring pressed rod 244, which rod is in turn pivoted to the carriage 1 at 245. The tension of the spring 246 urges the arms 240 and 24| in a clockwise direction about their pivots 242 to extend the operating bar 8 out into the space between the elevator and the hatchway walls. The free end of the arm 24| is beveled at 241 and is adapted to engage a roller 248 when the operator approaches the position which it occupies when the doors of the hatchway are closed in readiness for moving the elevator away from the oor. Roller 248 may conveniently be a ball bearing which is mounted upon the framework 3 of the operator in any convenient manner.

By this arrangement when the operator carrlage is movedinto its normal position, in which it is shown in Figure 26, the beveled portion 241 of the arm 24| rides over the bearing 248 and rotates the operating arm in a, counterclockwise e direction about its pivotal axis 242 against the tension of spring 246. l'I'lriis retracts the operator bar 8f from the latch mechanism of the elevator door and into a positionimmediately adjacent to the carriage 1 in which position it can move up and down in the elevator shaft without striking any obstruction. Arm 240 carries an adjust-l ingscrew 249 adapted to bear against the block 250 carried by the carriage 1 to thereby limit the direction will cause the bar 8 to ride over the movement of the operator bar outwardly from the carriage.

In Figures 24, 25, 26 and 27 I have shown a modied form of latch and keeper mechanism for the hatchway door, which mechanism can be used advantageously either with the form of operator shown in Figure 1 or with the modified form shown in Figures 21 to 23, inclusive. The modied form of latch shown in these latter iigures occupies less space in the hatchway than the latch mechanism shown in Figures 7 to 9, inclusive, and is therefore advantageous for use in installations where the clearance space between the hatchway walls and the elevator is rather small. As will be seen in Figures 24 andv 25 the' latch mechanism comprises a mounting plate adapted to be attached to the hatchway door. Usually this bracket will be mounted upon the roller bracket 252 by which the door is mounted'upon the rail 253 along which it slides to open. Themounting bracket |06' is generally L-shaped as before.

Adjustably mounted upon the fiat upper portion 254 of the bracket |09' is a stationary keeper plate 255. A movable latch 256 is mounted upon this plate by pivotal means 251 and urged to rotate in a counterclockwise direction, Figure 26, by a spring 258. A pin 259 carried by the latch 256 strikes against an edge 260 of the stationary plate -255 to limit the rotation of Vthe latch 256 under the action of spring 256.

Stationary plate 255 and latch plate 256 together form a generally rectangular socket 26E into which the operator bar 6 is moved, as shown in Figure 27.

The keeper plate 262 is carried by the brackets upon which the rod 253 is supported and contains projecting ears 263 with which the tongue portion 264 of the latch lever 256 are registered to lock the doors in their closed position.

in the operation of the device, when the carriage 1 is moved to the left, Figures 26 and 27,

under the action of motor |8, the tapered portion 241 of the operator bar rolls oif of the bearing 248 to permit the spring 246 to rotate the'arm in a clockwise direction to thereby bring the operator bar 8* into registration with the socket 26| in the latch mechanism. 'This arm 8 strikes against the edge of the plate 256 and rotates that plate.

in a clockwise direction about its pivot against the tension of spring 258. This rotation withdraws the latch tongue 264 from the ear 283 of the keeper plate to unlatch the doors and permit them to be moved upon their rail 253. The continued operation of the carriage 1' serves to move the doors from their closed to open position.

It will be noted that the line of thrust from the carriage 1 to the latch mechanism is not straight. In the event that the door strikes an obstruction, when moving to closed position. which is to the right as viewed in Figure 2'7, and the tension placed upon this line of thrust is therefore excessive, such .tension will have a component tending to rotate the operator arm 24U about its pivot 242 against the compression of spring 2.46. The latch mechanism 256 will also be rotated about its pivot 251, by reason of the tension imposed upon the arm 24U and the arm 248 will rotate free from the latch mechanism and thereby release the operator from the door. The carriage 1 will then continue on to its extreme position-and the door is then manually closed after the obstruction has been removed. A subsequent movement of the carriage in either beveled surfaces of the latch mechanism into engagement with the socket 26| to permit moving the door after the obstruction has been cleared.

The latch 256 is provided with an arm 265 which is adapted to be engaged by a rod 266 journaled to the door as at 261. Suitable manual means are adapted to move the rod to cause it to unlatch the doors, should manual operation of the same be desirable. This manual means may be of any desired construction. For example, it

may comprise a bell crank lever 320 pivotally mounted at 32| upon the elevator door. One arm 323 of this lever has the rod 266 pivotally secured thereto at 324 and the other arm 325 of the lever has one end of a push rod 326 pivotally secured thereto at'321. The other end of push rod 326 is pivotally secured at 328 to an operating handle 329, which handle is pivotally secured at .330 to a plate 33|, suitably secured to the eleva- `tor door. Moving the handle 329 to the left, as

Figures 24 `to 27, inclusive, includes also a set of interlocking contacts through which the operation of the driving motor of the elevator is controlled to prevent the elevator from being moved until all of the hatchway doors are closed and locked. This interlocking device comprises a pair of stationary contacts 210 and 21| carried upon a suitable insulator plate 212 within a house ing 213 which is mounted upon the bracket which holds the keeper plate of the latch. Circuit connections 214 are'extended through a suitable conduit 215 to these contacts.

A bracket member 216 is attached to the latch 256 and upstandstherefrom in juxtaposition to the contacts 210 and 21|. An insulator 211 is mounted upon the bracket 216. A square post 218 is attached to this insulator and projects therefrom toward the contacts 210 and 21|. A short circuiting bar 219 is slidably mounted upon the post 218 and is spring-pressed away from the insulator 218 by the coil spring 280. When the latch lever 256 is in its closed position, that is with the doors locked shut, short circuiting bar 219 engages the contacts 210 and 21| to electrically connect the same together, thereby completing the series interlocking circuit through these contacts. lWhen the latch 256 is rotated to unlock the doors the bar' 219 is moved away from these contacts to thereby break the interlocking circuit and prevent further movement of the elevator.

In Figures 30 and 3l I have shown a modied form of elevator shaft gate operator comprising a bar |40 carried by the carriage 1 and carrying a latch 28| which is notched to engage a pin |4I carried by the gate. The latch 28| is pivoted to the bar |40 at 282 and urged downwardly upon opened and closedsimultaneously with an open' ing and closing of the hatchway doors by the operator mechanism. Inithe event that the gatev strikes against an obstruction latch 28| isratated in a counterclockwise direction aboutits pivot 292 against the tension of spring 233 to release the pin |4| therefrom to permit the gate to come torest independently of the operator. By this arrangement the danger of injury to'a passenger in the car by reason of coming into contact with ,the mechanically operated gate 1s eliminated.

The modified door check shown at 25 and 29 in Figures 2l to 23, inclusive, is'shown in detail in Figures 28, 29 and 30. This check comprises a suitable casing 290 through which the shaft 21' is projected. 'Ihis shaft carries the operating lever 29 by which the check is connected with the moving carriage of the operator to retard the movement of that carriage. Within the casing 299 the shaft 21 carries a bell crank 29| keyed thereto by suitable means such as a set screw 292. Within the casing is a cylinder 293 in which a piston 294 is fitted. This piston contains an ear 295 which projects from the closed end 291 of the piston, which ear is connected to the bell crank 29| by a pair of links 299 disposed upon opposite sides of the ear 295 and crank 29| and suitably pivoted thereto.

'Ihe piston contains a disk-Llike wall 291 which contains a centrally located port 299 closed by a plate or valve 299 that is pressed thereagainst by a spring 300. The ear 295 contains a centrally located boss 30| which in turn carries a post 302 upon which the gate or valve 299 is slid- Projecting from the piston head thusformedis a piston skirt or hollow cylinder in the Walls of which are located a plurality of large ports indicated at 303. Leading out of the cylinder 293 is a port 304 normally closed by a valve 305 spring-pressed against its seat by a`suitable coil spring 306. The valve stem 301 and coil 'spring are held in place in the casing 290 by a suitable bushing 308 threaded therein. The tension of the spring 306 is adjusted by moving this bushing 309 inwardly or outwardly of the casing with a'wrench engaging the squared head 309 of the same. A

suitable cap 3|0l and lock nut 3|| are-threadedA upon the bushing 308 to maintain the adjustment intact once it has been set. The chamber within the casing'290 is completely filled with oil, or an equivalent fluid. f

In the operation of the check, with the parts thereof in the position in which they are shown in Figure28, the operator is in its normal position ready to resist movement of the carriage into its limit position. The normal position of the check is determined by the adjusting screw 320 which 'engages the operating arm 28' to position it. 'Ihe roller' 29 carried by the carriage engages the operating arm of the check and rotates the shaft 21 in a counterclockwise direction to move the piston 294 to the right, Figure 28, against the pressure of the oil confined in the cylinder 293. It will be noted that this pressureaids the pressure of spring 300 in maintaining the valve 299 closed so that no oil can leak therethrough. At the beginning of the movement oi' the shaft 27',

'ports 303 in the piston skirt register with a V-shaped slot 3|2 in the cylinder wall, to permit the escape of oil from the cylinder. The initial movement of the piston is therefore relatively unresisted and as the piston moves to the right, the slot 3I2 is gradually closed to seal the cylinder and build up oil pressure therein. As the piston continues to move to the right the pressure in the cylinder 293 is increased until it is suliiclent to unseat the valve 305 and permit gradual escape of the oil from the cylinder into the chamber 3 I3 in which the bell crank is located. At the time that'the valve 305 is unseated, the piston will have been moved to the right suillciently to position the skirt 294 across the port 304. With the piston in this position the right hand one of the ports 303, Figure 28, is registered with the port 394. Oil can ilow through the ports 393 and 304 into the hollow space 3| 4 within the valve 305. Ports 3|5 lead radially outwardly from the valve 4and communicate with an annular groove 3|9 .which extends around the valve. When the valve 293. By this arrangement the check opposes the movement of the carriage by an amount which gradually increases to thereby decrease the speed ofthe carriage and thereby gradually bring it to rest without shock.

- When the carriage of the operator is moved in the opposite direction the shaft 21 is rotated in a clockwise direction and bell crank 29| thereby operated to move the piston to the left into the position in which it is shown in Figure 28. This movement immediately decreases the pressure in the cylinder and causes valve 305 to be reseated and thereby close -oi port 304. Pressure is now built up upon the front side of the piston head 291 against the valve 299, this pressure soon overcoming the pressure of the spring 300 to unseat the valve and permit flow of oil through the port 293. Since this port is large oil rapidly flows into the cylinder and the resistance to movement of the shaft 21' is small. therefore is effective to introduce a large resistance to movement of its shaft in one direction and a very small resistance to movement of its shaft in the opposite direction. By this arrangement the carriage of the operator can be rapidly brought to rest without shock and at the same time the carriage can be started in a reverse direction from rest without encountering an appreciable resistance from the checking mechanism. With the checking device of the type shown in Figure 28 the usual electromagnetic de- -vices by which motor circuits are controlled to bring the motor gradually up to speed may conveniently be used in connection with motor I3 if desired, such devices being well known and commercially available, have been omitted from the drawings as unnecessary.

What is claimed is:

l. A door operator mechanism for opening and closing the hatchway doors of 'an elevator comprising, a carriage mounted on the elevator, means on the elevator for moving said carriage, a latch on each door in the hatchway, a keeper plate mounted in the hatchway and engaged by said latch to lock thev door closed, an operator bar carried by said carriage including a lever pivoted thereon intermediate its ends, means associated with the opposite ends oi said lever and operated by `a movement of said carriage for moving said bar outwardly from the-carriage into engagement with the latch of one of said doors to operate the same rst to unlock and then to open said door, means associated with saidlever for disengaging the same from said latch when the movement of the door is obstructed, and a pair of interlocking circuit contacts opened by the movement of said latch in The checking device

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