US 1581459 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
April zo ,1926.
D. 1 LINDQUlsT' ELEVATOR SAFETY. APPLIANCE I5 Sheets-Sheet l Filed July 11, 1924 F/GZ April -zo 1926. 1,581,459 D. L. LINDQUIST ELEVATOR SAFETY APPLIANCE Fired July 11 1924 s sheets-sheet 2 mmv-A L.
325% Xu @lum/14% April 20, 1926. 1,581,459
D. L. LINDQUIST ELEVATOR SAFETY APPLIANCE.
Filed July 11, 1924 5 Sheets-Sheet 5 /OMAALLW i Patented Apr. 20, 1926.
UNITED .STATES PATENT OFFICE.
DAVID L. LINIDQUIST,` OF HARTSDALE, NEW YORK, ASSIGNOR T OTIS ELEVTOR COMPANY, OF JERSEY CITY, NEW JERSEY, .A CORPORATIONOF NEW JERSEY.
ELEVATOR SAFETY AEPLIANCE.
Application iled July 11,
To all who/u il'. may coaccm: f
Be it known that I, DAVID L. LrNDQUis'r,
a subject of the King` of Sweden, residing in Hartsdalc, in the county of lVestchester and State of New York, have invented a new and useful lniproven'ient in Elevator Safety Appliances, of which the following is a specification.
This invention relates to safety devices for the parts of an elevator system traveling in the hatcliivay, and particularly to safety brakes adapted to be applied to a stationary rail for bringing the moving parts to a stop in the event of their traveling above predetermined speeds or too far beyond their upper and lower limits of travel.
One object of the invention is to apply a substantially constant retarding force 1n predetermined amount to bring the moving parts t0 a stop Whenever the safety device is actuated.
Another object is to provide a safety,
brake which after it has been applied to stop the moving` parts will be released upon their being moved in the reverse direction.
A further object is to provide means for applying the safety brake when the'moving parts have reached a predetermined point in the hatchiv'ay regardless nof their speed.
A further object is to provide means for applying the safety 'brake should the retardation of the elevator car in approaching a terminal landing be insufficient to bring it to a stop Within the normal limits of travel.
A further object of the invention is to provide flexible guide shoes for the moving parts which guide shoes will yieldingly engage the guide rails.
Other objects will appear from the specication and claims.
In a preferred embodiment of theinvention the safetybrake, which is mounted on the elevator car, has'a pair of brake r shoes disposed on opposite sides of the guide rail and arranged to be brought .into engagement with the guide rail when the safety brake is applied. The brake shoes are pivotally mounted on links` Which, in
v connection with the roel-:ing jaws, act to exert a pressure betweenthe shoes and the rail. The amount of such pressure is auto matically regulated by an adjustable re- 1924. serial No. 725,429.
silient force acting substantially parallel to the rail, and this resilient force determines the retarding effort. The organization of parts is such that When the car has been brought to rest by the s-afety brake on the guide rail of normal thickness, .it can be` start-ed in the opposite direction by the hoisting mechanism, Without the necessity of first manually disengaging the parts of the safety brake from the rail. A governor is provided for applyingl the safety brake in the event that the moving parts should travel above a predetermined speed -along their path of travel. Means are'provided for applying the safety brake to stop the car in the event that the speed of. the car has not decreased to a predetermined speed When the car is at a given distance from'its lowest stopping` point and means are-provided for applyingthe safety brake in the event that the elevator car continues to travel below the said stopping point.V Means are also provided for applying the safety brake in the event that the car travels above its highest stopping point. This latter is accomplished by employing a guide rail having an increased thickness at its upper end Which Will be engaged by the brake shoes as they pass upwardly upon this section of the rail. In this event the safety brake Will be applied under a resilient force acting oppositely to the before mentioned resilient force and in suoli a manner as to lock the elevator car until the safety brake has been manually released. vThe elevator car is provided With flexible guide shoes which Will yieldingly engage the rails throughout their length for Yproperly guiding the car and which will permit of the car passing along a portion of the rail having an increased thickness.
In the accompanying draw-ings, 95
Figure 1 is aschematie view of an elevator system to Whiclnsafety devices in accordance with this invention are applied,
Figure 2is a front elevation Ona. larger scale of a portion of the rail used in the elevator system shown in Figure l,
Figure 3 is an end elevation of the .safety brake in released position and shows operating mechanism therefor, l
Figure 4 is a sectional View taken lon line 105 L.l2- 1L of Figure 3,
7--7 of Figure 3.
Referring to Figure 1, the elevator system includes a car 10 which is suspended by cables'll extending over a hoisting drum 12 `to counterweight 13. The drum 12 is driven by a motor 14 and has an electromagnetic brake 15. Stationary guide rails 16 are provided and the car 10 has an upper set of guide shoes 17 and\lower set of guide shoes 18 which engage rails 16. The thickness I of the guide rails is increased above th-e point i 19, Figure 1, in the manner shown -in Figure 2 for a purpose to be hereinafter pointed out.
Safety brakes 2O are mounted one on each end of a safety plank 21 which is secured to the bottom of the car.
Two governors, 22 and 23, operate to apply the safety brakes under certain conditions, and a cam 24 in the elevator pit acts to apply the safety brake in the event that the car should travel below its lowest landing.
Governor 22 is driven by the car through a governor rope 25. A hitch 26 is fastened to rope 25 and is normally held in a releasing carrier 27 attached to the elevator car. This governor is provided -with jaws .28 and 29 which are adapted to grip the governor rope 25 inthe event that the governor is tripped due to an excessive speed. Jaws 28 and 29 have a gear connection between them so that they will operate together. Jaw 28 is pivoted at 30 and is provided with an arm 31 to which a link 32 of the governor is operatively attached. A spring pressed latch 33 engages the end of arm 31 until such a time as the governor reaches the speed for which it is adjusted to act whereupon latch 33 releases arm 31. When arm 31 is released link 32 raises arm 31 so as to close jaws 28 and 29 upon the governor rope 25 and thus stop its movement. J aw 29 is pivotally mounted at ,34 on a rod 35 which is slidably carried in a4 guide support 36 and provided with a spring 37 which urges the jaw 29 into engagement with the governor rope l25 but allows rope 25 to slide through the jaws when the tension exceeds an amount determined by the pressure of spring 37. When the governor acts due to overspeed of the car in the down direction, hitch 26 is withdrawn .from releasing carrier 27 and as the elevator descends a tension is exerted on a rope 38 to apply safety brakes rope 39 which ls fastened at 40 to the elevator car so as to operate the governor in accordance with -the speed of the car. This governor is adapted to project a cam 41 outwardly into the elevator hatchway for applying the safety brake in the event that the elevator car should travel over apredetermined speed as it approaches its lowest landing 42. Cam 41 is secured on one end of a rod 43 slidably mounted in supports 44. The other end of rod 43 is connected-with an end of toggle 45 which is pivotally secured at its other end to an abutment 46. A link 47 connects toggle 45 with a lever 48 which is operated by governor 23 which operates to straighten the toggle when the governor is operating above a predetermined speed. rlwo spring catches 49 and 50 aremounted on link 47 which are adapted to be engaged by spring pressed latches 51 and 52 ona stationary support 53. Catch 49 is adapted to pass latch 51 when the governor operates above a certain speed and to be engaged thereby until the speed has decreased to a speed which is not excessive for the moving parts of the elevator system when the car is running in the hatchway in the vicinity of the lowest landing. Catch and latch 52 are operative to hold the cam in its retracted position, as shown in Figure 1, until the speed of the car, and consequently the governor, has increased above the4 speed at which the elevator normally travels when it passes cam 41 in running upwardly from its lowest position inthe elevator hatchway.
When this speed has been exceeded the latch' vreleases and allows the governor to project nam 41 outwardly into the hatchway. The operation of cams 41 and 24 to apply the safety brakes 2O will be hereinafter set forth.
Referring to Figure 3, the safety plank 21, upon which safety brakes 20 are mounted, comprises two channels 54 and 55 secured in spaced relation by means of upper and lower plates 56 and 57 respectively. Abutments 58 are secured to the channels at their ends on opposite sides of the guide rails 16 and are provided with lower projections 59 for guiding actuating rods 60` for the jaw members 61 and 62.
The abutments 58 are each provided with projecting ears 63 and bolts or pivot pins 64 passing through these ears and the jaw members 61 and 62 afford pivotal connections for carrying the jaw members on the abutments. The jaw members are free to swing on the pivot pins 64 between. adjustable spring stops 66 carried. by thc lower projections 59 and adjustable fixed stops 65 comprising bolts which pass through the abutmonts 58 and the channel members 54 and 55. The spring stops 66 comprise bolts having springs 67 and nuts 68 which engage the. ends of the bolts extending through the for the jaw members in their released position.
Between each of jaw members 61 and 62 and the rails 16 is a brake shoe 69. The
.each side of jaw member shoes 69 are mounted on links 70 which extend between them and the jaw members. The ends .of the links are rounded and tit in corresponding cylindrical bearings formed in recesses in the jaw .members 6l and 62, and in the brake shoes- 69. It will be noted that the upper and lower wallsot` these recessesv are cut away to permit rocking movement ot the links. with respect to the jaw members and the brake shoes with respect to the links. f The lower walls 71 of' the recesses in the jaw members project slightly and perform the function of stops for limiting the downward rocking movement ot the links 70.
The links are pivotally connected at their ends with the jaw members and with the brake shoes. Referring Ito Figures 3 and 4, a side plate 72 is shown secured on 62, by screws 73. These side plates overlap the ends of links 70 and have pivotal connections thereto by pins 74. The opposite ends of links 70 are provided with slots 75 which receive webs 76 extending lengthwise of shoes 69 in the recesses in them. Pivot pins 77 connect the links 70 with the brake shoes 69 by passing through the ends of links 70 and webs 76 of the brake shoes. The axes of the pins 74 and 77 are coincident with the aXesof the cylindrical bearings for the ends of the links. The arms of yoke 78 are pivoted on pins 77 and pass around the upper portion of the brake shoes. vThe outward thrust of the brakeshoes is transmitted to the jaws through the cylindrical bearings and links 70 so that thel'plates 72 and pins 74 are not called upon to transmit this thrust, but serve to hold the par-ts assembled. Springs 79 urge the brake shoes 69 downwardly about pins 7 4 in the jaw members 61 and 62, so that the links 70 are in engagement with projections 71 of the jaw members. Springs 79 are positioned between the yokes 78 and a projection 80 on the upper end of the jaw members and adjusting screws 81 serve to regulate the pressure exerted by springs 79.
In using the safety brakes 20 in conjunction with guide rails having an`increased' thickness for a portion of their length, the
car -is provided with flexible guide shoes 17 and 18 which will 'accommodate themselves to the different thicknesses of the guide rails. These flexible guide shoes adjust themselves to any unevenness of'the rails and provide a smoother operation of the elevator car in the hatchway.l
The construction of the guide shoes is shown in Figures 3, 6 and 7. Channel '84 is secured to the upper cross plate. 56 of the safety plank by means of bolts 82 extending through projections 83 on cross plate 56 and channel 84. Channel 84 provides a support for the shoes 85 which engage the sides ut rail 16. These shoes are provided with bolts 86 which extend through lapertures in the channel, and outside ot the channel the bolts are provided with adjusting nuts 87 and lock nuts 88 for limiting the inward movement 'of the shoes. Springs 89 are positioned on the bolts '86 between the shoes 85 and the channel 84 for yieldingly pressing the shoes 85 toward the rail. The channel is further provided with a spring pressed guide plate 90 which engages the inner edge of rail 16. Plate 90 is supported on the back of thel channel by means of bolts 91 lpassing through it and the channel, and on these bolts between the plate and the springs 92. lBolts 91 are provided with adjust-ing nuts 93 and lock nuts 94 so that the plate can be adjusted with respect to the distanceV between the. guide rails.
The actuating mechanism for the safety brake comprises rods 60 arranged so as to pass vertically upward through projections 59 of the abutments 58. Rods 60 are adapted to be moved intfo engagement with the lower projections 95 of the jaw members 61 and 62 and to swing them upwardly on their pivotal connections with the abutments 58 until the brake shoes enga-ge the rail 16. Rods 60 are provided with springs 96 positioned between heads 97 on their lower ends and the channel are I projections 59 whereby they will be held l down away from the 62 except when they are movedup by the cams 98. Cams 98 engage the heads 97'y of rods 60 and are mounted. on the ends ot a pair of shafts 99. Theseshafts are carried by supports 100 extending from thebottom of safety plank 21 and are connected by a pair of gears 101 so as to be rotated together. A beveled gear 102 is'secured to the back by a corresponding beveled gear 103 secured to a shaft 104. two hangers 105 and 106 and it is provided with a torsion spring 107- which tends to hold it in the released'position shown in Figures 1 and 3. Shaft 104 also has a lever arm 108 to which is connected a. rope 38 and a. link 110. A
The rope 38 extends from lever arm`108 and'passes over a sheave 111, supported to one side of the elevator car,
and from there rope 38 extends to the hitch 26 to which it is connected so as to opera-te the safety brakes from governor 22..
The link 110 connected with lever arm'108 extends to a lever 112. which lever is connected bv means of a pivot 118 to a. support 114 extending from the bottom of the ele- Shatt 104 is supported by.
jaw lmembers 61 and oi one otgears 101 to be'driven vator ear. Lever 112 has its upperarm 115 extending beyond the side of the elevator ear and is provided with a roller 116 which is adapted to engage the cam 41 for actuating the lever for applying the safety brakes by meansof governor 23, or toi engage the cam 24 for applying the safety brakes.
The operation of the safety brakes is as follows. Assuming that the elevator vCar istraveling downward at an excessive speed, governor 22 trips, and jaws 28 and 29 grip the governor rope 25, to bring it to a stop. Hitch 26 is withdrawn from carrier 27 and, as the car lproceeds downwardly, rope 38 acting through lever arm 108 rotatesshaft 104 against spring 107. The rotation of shaft 104 causes lrotation of shafts 99 through gears 103, 102 and 101. Cams 98 raise actuating rods against springs 96.v As rods 60 move upwardly they engage the projec` tions 95 on the jaw members 6l`and 62, rocking these members on their pivots 64 upwardly from their position in Figure 3 until the brake shoes 69 are brought into frictional engagement with rail 16. Due to the fric`- tion, jaws 61 and 62 rock upwardly about their pivots 64 while at the same timeshoes 69 swing upwardly on links 70 about pins 74.and thereby compress springs 79. The jaws, links and shoes are so proportioned and the relative positions of their pivotal points so selected that the compound motion `of the parts results in a gradual increase of friction or retarding force until the portion 117 ofthe jaws come into engagement with the stops 65. The parts are then in the positions shown in Figure 5 and the safety brake is applied. l/Vere the retarding force to become greater, springs 79 would compress, thereby permitting the brake shoes 69 to move away from rail 16 by swinging on links 70. Such movement would decrease the pressure acting to hold the brake shoes against the rail and consequently the retarding force. The retarding force Iof the brake shoes may be varied by adjusting the positions-of stops 65`and the pressure of springs 79 by means of the screws 81, and this re tarding force will remain substantially con` stant for any adjustment, independent of the condition of the rail or surfaces of the brake shoes.
In applying the safety brakes, rope 38 rotates shaft 104 .through an angle of 90 and when leyer arm 108 has reached a horizontal position, rope 38, acting 'through hitch 26, draws the governor rope 25 through jaws 28 and 29 until the elevator stops. Vhen it is desired to reset the mechanism, jaws 28 and 29 are manually released from rope 25 and latch 33 is reset. Hitch 26 is replaced in the releasing carrier 27 on-the elevator. Spring 107 operating upon shaft 104 rotates the cams 98 from the position shown will return the brake shoes 69 to their lower position and thereby eect a release of the safety brakes.
It is to be noted that governor 22 operates tov apply the safety brakes inthe event of an excessive speed of the elevator car in a downward direction in any part of the elevator hatchway in the manner above set forth.
Governor 23 is provided to apply the safet'y brakes in the event that the elevator car should fail to get the proper slow-down as it approaches the lower landing 42, as for instance, in case the power supplied to the hoisting motor should be interrupted. The operation of this governor in applying the safety brakes under these conditions is as follows. Cam 41 is projected outwardly into the hatchway by` the governor 23 while the elevator car is'runninof at full speed in either directionl in the hatc way, and the cam is maintained in such a position by the toggle k ping, the speed of the elevator car will have A decreased sufciently by the time roller 116 passes the point at which cam 41 is located to insure cam 41 being retracted by governor 23. In the event that the car is not at a suliiciently low speed in this position, cam 41 willbe held out and be engaged by the roller 116 on lever 112 and thereby tilt this lever. Link 110 actin on lever arm 108 applies the safety bra es by the turning of the shaft 104 and shafts 99 with their cams 98 as already described. As the car is stopped roller116 may have run 0H the lower end'of cam 41 so that lever 112 and the operating mechanism connected therewith return to the position shown in Figure 1 and 3.
In order to allow the elevator car to travel up the hatchway without applying the safety brakes, the catch 50 and latch 52 serve the function of retaining the governor elements in a position so that cam 41 will be held in retracted position until the elevator car has attained a certain speed. In the normal operation of the elevator system the elevator car does-not accelerate to a speed suicient to effect a release of the catch 50 before roller 116 has passed cam 41.
In the event that the elevator car should continue to travel below the lower landing by more than a predetermined distance, rolln -operative position as shown in Figure 3.
' Governor 23 does not require manual resetting as in the case of theV actuation of kgovernor 22, but is automatic in its vaction as previously described.
To prevent cam 24 from actuating the safety brakes upon operation of the elevator car in the up direction after roller 116 has passed the cam in the down direction, it is pivoted at 118 and rests upon a stop 119 so that when the car-is traveling up, roller 116 will engage the portion 12() and raise the cam up out of the path of the roller.
In the event that the elevator car travels in the 'up direction too far above the top landing, as for example, due to proper slowdown not beingobtained, the safety brakes will be applied. The application in this case is accomplished by the shoes engaging the thickened portions of the rails to rock jaws 61 and 62 about pivots'l against the action of springs67. (See Figure 6.)v The retarding force is determined by the pressure exerted by springs 67 and is substantially constant since, were the friction be-v tvveen the rail and the shoes to become greater, springs 67 would give and permit the shoes together With jaws 61 and 62 to rock about pivots 64. The operation of the safety devices in this instance is independent of the governors.
After the safety brakes have been applied to the rail of increased thickness they operate tov hold the elevator in that portion of the 'hatchvvay The safety brakes are not self-releasing on the thickened portion of the rail, and When it is desired to release the safety brakes nuts 68 are turned so as to compress springs 67 until the stops 66 Will no longer exert Aa thrust on the brake shoes 69. The elevator car may then be operated in an up direction, thereby effecting a release of the brake shoes. When the elevator car has been moved again onto the rail of normal thickness the nuts 68 may be readjuste'd, so that the stops will perform the functions required.
Although in the foregoing disclosure the safety brakes have been described as mounted on the elevator car, it Will be understood that safety brakes may be similarly used in connection with other moving parts of the elevator system.
Itis to be noted that the invention provides means for applying a safety brake to stop the car whenever it travels beyond set limits of travel in either direction; also that the safety brake will be applied due to over speed of the car or in case the normal slowdown has not operated to bring the car to a stop Within the limits of its travel; also that the retarding force in the up direction is independent of that in the down direction and either may be of any desired amount.
The safety brake may be` employed to ,act-
in place of the buffe-rs in the elevator pit or it may be arranged to provide a part of the retarding force for stopping the car, in
' Which event` it may be used in conjunction with buffers in the pit.
What is claimed is 1. In an elevator systemthe combination of a safety brake on a moving part in the hatchway adapted to grip a stationary memhatclnvay adapted togrip a stationary mem-` ber along the path of the moving part, and meansfor applying said safety brake in the event that the moving part should pass beyond a predetermined point, said means being inoperative for applying said safety brake upon the reverse operation of the moving part.
3. In an elevator system, a moving part in the elevator hatchway, a stationary member along the path of the moving part, asafetyr brake onsaid moving part operable to grip said stationary member 'when the moving part is operating in one direction, and means for causing the operation of the safety brake in the event that the moving part is operating at or above a predetermined lower than normalv speed as a point on said moving part reachesa predetermined point inthe hatch- Way but permitting the continued operation of said moving part Without causing the operation of the safety brake in the event that the moving part isoperating belovs7 said predetermined speed as said point on the mov.- ing part reaches said point in the hatchvvay, said safety brake, when operated, being releasable from said stationary member by the operation of the'movingpart in the opposite direction.
4. In an elevator system, the combination of a safety brake on a moving' part in the hatchWay adapted to be applied between its .normal limits of travel for retarding the moving part When operating in its down direction and to be released by the operation of the movingipart in its up direction, and means for applying said safety brake in the event that the moving part should pass below a predetermined point, saidfm'eans being f one direction and adapted to be tilted upon its pivot by said actuating means by movement ofthe car in the` other direction to prevent the safety brake from being applied by the reverse movement of the car.
. 7. In an elevator system, a moving part 1n the hatchway, a member carried by and operable to control said moving part, `and a cam in the hatchway for causing the operation of said member, upon its engagement with said member withl the moving part traveling in one direction, said cam being displaceable by said member, \without causing the operation thereof, upon its engagement with said member` with the moving vpart traveling' in the other direction.
8. In an elevator system, a moving part in the hatchway, a motor for ralsing or lowering said moving part, a' stationary member along the path of said moving part, a safety brake on said moving part for cooperating Y with said stationary member, and means for causing the application of the safety brake to said stationary member lin the event that the speed of the moving part is not sutilc-ie'ntly reduced as it approaches its normal limit of travel due to the failure ofl the power supplied to said motor.
` 9. In an elevator system, amoving part in the hatchway, a stationary member along the path of said moving part, a safety brake on said moving part for cooperating with said A stationary member, and means for causing the application of the safety brake to said guide rail in the event that the moving partA 1s operating at yor above a predetermined lower` than normal-speed as a point on said lmoving part reachesla predetermined point in the hatchway but permitting the continued operation of said moving part without causing the operation of the safety brake in the event that the moving part is operating below said predetermined speed as said point on thev moving part reaches said point in the hatchway.`
1,0.` In an elevator system, an elevatorar, a guide rail, a safety brake on said car for cooperating with said guide rail, andmeans for causing Athe application of the safety brake to, said guide rail only in the event that the speed of the car is not suiiiciently reduced as it approaches a predetermined point. .j
1l. In an elevator system, the combination of a safety brake on the elevator car adapted to cooperate with the elevator guide rail, and means for applying the safety brake to said guide rail in the event that the speed of the elevator car isnot'suiiiciently reduced as it approaches its normal limit of travel.
12.' 'In an elevator system,- the combination of a safety brake on a moving part adapted I to cooperate with a stationary member along its path, means for applying the safety brake to said stationary member in the event that the moving part travels above one'predetermined speed in one portion of its path, and means for applying the safety brake to said stationary member in the event that the moving part travels above another Y predetermined speed in another portion of its path. I
13. In an elevator system, the combination ofa safety brake' onthe elevator ca r adapted to cooperate with the elevator guide rail, means -or applying said safety brake in theevent that theelevator car travels at an excessive speed, and means adjacent to the limit of travel of the elevator car for applying the safety brake in the event that the speed of the elevator car is not sufficiently reduced as it approaches said limit.
14. In an elevator system, the combination ofa movable cam in the elevator hatchway adapted tqbeengaged by a moving' member from according to the speed at which the' governor is driven.
16. In an elevator system, the combination of a movable cam in the elevator hatchway adapted to be engaged by a moving member when said cam is in. its outermost position, a governor driven by the elevator car, a connection between the governor and said cam for projecting it into the path of the moving j member and for retracting it therefrom according to the speed of the elevator car, means for lpreventing the 'governor from projecting said cam outwardly until the speed of the car .has attained a predetermined speed, and means for preventing the governor from retracting said c am from its Y speed as it approaches its limit of travel, anda guide rail therefor, a safety brake on said car operable to grip said guide rail, agovernor driven by said elevator car, and means actuated by said governor for causing the operation of said safety brake When the elevator car reaches a predetermined point in the elevator hatchway, in the event` that the car is traveling at or above a predetermined lower than normal speed as it arrives at said point, but permitting operation of I"said car without causing the operation of said safety brake, in the event that the car is traveling below said predetermined speed when it reaches said point.
19. In an elevator system, the combination of a safety brake on a moving part adapted to cooperate with a stationary member along its path, means for applying the safety brake in the event that the moving` part travels at an excessive speed, means for applying the safety brake in the event that the moving part is traveling above a predetermined means for applying the safety brake. in the event that the moving part should pass beyond its normal limit of travel. y
20. In an elevator system including a guide rail for the elevator car, the combination of an elevatoncar having a safetybrake thereon adapted to be actuated to grip the elevator guide rail', governor means operative to actuate said safetybr'a'ke into gripping yengagement with the rail when the elevator car is traveling above ai predetermined speed, and a second governor means operative at a` point adiacent to .the lovver ylimit of travelof the-elevator'car for applying said safety brake in the event that the elevator car is traveling above another predetermined speed as it approaches said` limit.
21. In an elevator system including a guide rail for the elevator car,'the` combination of an elevator car having a safety brake thereon adaptedto be actuated to grip the i' elevatorguide rail. governor means operative tol actiiate said safety brake into gripping engagement with the rail When the elevator car is traveling above a predeter mined speed, a'second governor means operative at a point adjacent to the lower limit of travel of the elevator car for yapplying said safety brake in the event that the elevator carl is traveling-above another predetermined speed as it approaches said' limit, and means operative below said point forapplying said safety bra-ke in the event'that the elevator car shoiildtravel beloivitsj normal vlowerlimit of travel.`
22. In an elevator system includingv a guide rail for the elevator car, the. combination of an elevator car having a safety brake thereon adapted to be actuated to grip the elevator guide rail, governor means operative to actiiate said safety brake into gripping engagement With-.the ,rail when the elevator car is traveling above a predetermined speed, a second governormeans operative at a point adjacent to the lower limit of travel i .of the elevator. lcar for applying said safety brake in the event that the elevator car is traveling above 4vanother predetermined 'speed as it approaches said limit, means operative below said point for applying said safety brake in the eventjthat the elevator travels below its normal 'lower limit of travel, iand'inea-ns in the upper portion 'of the elevator hatcliwa'y operative for applying the safety brake in the event that the elevator car travels above its normal upper limit of travel. v
23. In an elevator system including a guide rail for the elevator car, the combination of an elevator car having a safety'brake thereon adapted to be actuated to-grip the elevator guide rail, governor means operative to actiiate said safety brake into gripping yengagement with the rail When the elevator car `is traveling above a predeter- Imined speed, andnieans in the upper portion of the elevator hatchivay `operative for.
applying the safety brake in the event that the elevator car travels above its normal upper limit of travel.
24. In an elevator system, an elevator cai', a guide rail therefor, 'a safety brake on said elevator car voperable to' grip said guide rail, means for causing the operation of said safety brake in t-lie event that the car runs at av predetermined` speed above its normal speed, 'and means for causing the operation of said safety brake inthe event that the speed of the car is not suiiiciently reduced below normal as it approaches its normal limit of travel.
25. In' an. elevator system including a guide rail for the elevator car, the combination of an elevator car havinga safety brake thereon adapted to beaetuated to grip the elevator guide rail,van actuating member for the travel ofthe car, and a second operating member adapted to be engagedl by and 'y cooperate with said actuating member to apthe hatchway.
ply the brake at a `predetermined point in 26. In an elevator system including a guide rail for the elevator car, the combinament therewith, means for actuating said ing said brake brake members into engagement with the trail,
said means comprising a pair of rods one on each side of the guide railfor engaging each of the brake members, a cam engaging f the oiter end-of each rod adapted to actuate it, a shaft carrying eachcam, a gear on each shaft for actuating 4the members simultaneously and means for turning said shafts for applying the safety brake'.
i 27. In an elevator system -including a guide rail for the elevator car, the combi nation of an elevator car having a safety brake thereon, comprising a pair 4of pivotally mountedshoes, one on each side ofthe elevator guide rail and adapted to be operatedinto braking position with the rail by movement of the elevator car in one direction and to be released from such braking position by movement of the elevator car in the opposite direction, and means for bringshoes into contactwith the rail.
28. y In an elevator system; an elevator car; a guide rail'therefor; and a safety brake on said car for cooperating with said rail, said safety 'brake comprising supporting means,
' one on each side of said rail, abrake shoe carried by each supporting means, and yielding means for maintaining said shoes in engagement with said rail, said, shoes being mounted in their supporting means-to swing in a direction upwardly and slightly away from the rail, upon the friction between the shoes and the rail exceeding a predetermined amount, against the force of saidyielding means whereby the retarding force exerted by said safety brake is maintained substantially constant. i
y 29. In anelevator system, an elevator car,
afguide rail therefor,l said guide rail having onethlckness for one hatchway zone and afdil'erent thickness for 'another hatchway z'one, a safety 'brakeon said car for` gripping said rail as it moves into said one hatchway Zone with the Acar traveling in one direction, and means for causing the application of said safety brake to said rail' while it is'rin saidother hatchway zone with the car traveling in the other direction.
A'30.' In an' elevator system including Aa guide rail-having one thickness for a portionof'its length and an increased thickness for another portionu of its length, an elevator vto guide the car, said guide having shoes arranged one on eachside of said rail, and
resilient means for'pressing said slices toward the sides of said rail,A said resilient means yielding to permit the spreading of said shoes as they passinto cooperation with the portion of the rail of increased thickness.
31. In an elevator system, a guide rail in the elevator hatchway having lone thickness throughout the normal pathof'travel of the elevator car, andhaving an increased thickness for a distance above the normal path of travel of the car. .I
y 32. In an elevator system, the combination of a guide rail having a varying thickness and guide shoes mounted on the elevator car for cooperatin with said rail, said guide shoes being provi ed with means for yieldpglly pressing them toward the sides of said 33. In an elevator system, a guide shoe for cooperating with the elevator guide rail, said guide shoe com rising a pair of shoes, one on each side of t e rail, abutment members outside of the shoes, and springs between the shoes and Vsaid members for yieldingly holding the shoesi in engagement with the rail. I i
34. In an elevator system, a guide shoe for cooperating with the elevator guide rail, said guide shoe# comprising a supporting member carrying sprmg pressed shoes for yieldingly engaging `the sidesof the rail and a spring pressedshoe for engaging the edge of the rail.
35. A safety brake for elevators, comprising a pair of rocking jaws, means for pivotally supporting said jaws on the elevator car on opposite sides of theelevator guide rail, a brake shoe carried by each of the jaws adapted to grip said rail, and means for rocking said jaws to cause said brake shoes to engage'the rail.
36. A safety brake for elevators compris- 37.-A safety, brake for elevators comprising an abutment member on each side of the elevator guide rail, an upper and a lower stop on each abutment, a jaw pivotally cony nected to 4each of said abutments and adapted to swing between said stops, a brake shoe between each of said jaws and said rail, links between said jaws and Said shoes for connecting said shoes to the jaws and for transmitting a thrust to the shoes, springsl between the upper ends of the shoes and the jaws arranged to exert a pressure on said 'shoes in a with therail, rods extending through the lower ends. 'of said abutments adapted to be actuated for rocking said jaws, springs on the rods between said abutments and the lower ends of 'said rods for holding the rods away from the jaws, and means adapted to raise said rods so as to actuate the jaws to a position where the brake shoes will engage the rail'.
38. A safety brake .for elevators comprising abutments on each side of the elevator guide rail, a jaw member pivotally supported on each of said abutments, a brake shoe pivotally carried by each, jaw member adapted to be brought into engagement with the rail by the swinging of said jaw memberson their pivots, said brake members being adapted to swing upwardly on their pivots with respect to the said jaw members. 3 9'. A safety brake for elevators comprising an abutment on each side of the elevator guide rail, a jaw member pivotally supported on said abutments, a'brake shoe pivotally carried by each jaw member so as to swing with-respect to the jaw members, a`
spring between'eaoh shoe and its jaw member arranged to exert a pressure on sai shoe in a with .the rail whereby a substantially. constant retarding force between the shoe and the rail is obtained when the shoes are brought into engagement with the rail and means for swinging the vjaw members for bringing the brake shoes into engagement with the rail.
ing an abutment on each side of the elevator guide rail, a jaw'member pivotally connected with each abutment and carrying a brake shoe adapted to engage the guide rail, and a spring stop 'for the jaw member carrie bythe supporting member.
41. A safety brake for elevators comprisy ing an abutment on each side of the elevator guide rail, a fixed stop on the upper portion of each abutment and a springstop on the lower portion. of each abutment,l a jaw member pivotally carried by theabutment and adapted to swing between said stops, an actuating rod for each jaw member adapted to engage the member and swing it upwardly, abrake shoe pivotallycarried by each jaw member, a spring between direction substantially 'parailel direction substantially parallel '.of the elevator car,
40. A safety brake for elevators compris-` d of a moving part havin each jaw abutment, said jaw members each having a.
recess providing va seat and a stop in the jaw along the lower surface of the recess, a
brake shoe between each jaw member and -the rail, said brake shoes each having a recess providing a seat, a link positioned with its ends in said recesses in pivotal relation A therewith, pivot pins extending throughthe ends of the 'links affordin connections between the jaws and bra e shoes.I and a spring between each jaw member and the pivot extending through the brake shoe connected therewith for yieldingly retaining the brake shoe outward from the jaw member and the link in engagement with the stop at the bottom of the recess in the jaw member.
43, In an elevator system including a guide rail for the elevator car, the combination of an elevator car having a safetybrake thereon adapted to be actuated to 'gripjthe elevator guide rail, means forl actuating said safety brake into gripping engagement with the rail when the elevator car is traveling downwardly, means for automatically releasin ,said safety brake after such an apd plicatlon to the rail by a reverse movement j j t and means forv applying 'said safety brake to the rail inthe event that the elevator car travels above a predetermined point and for locking it in such applied position.
44. In an elevator system, a mov part having a safety brake thereon'ada te to be applied and act with one retardiing force when the moving part is operating in one direction and to be applied and act with a .different retarding force when the moving part is operating in the other direction.
45. In an elevator system the combination a safety brake thereon, means for .app ying the safety brake, means for regulating the retarding forcewith which the safety brake will be applied when the moving part is operating in one direction, and means for regulating the retarding force with which the safety brake will be applied when the moving part is operating in the Iotherl direction.
In testimony whereof, I have signed my name to this specification.
DAVID L. LINDQUIST.