US1027840A

US1027840A - Elevator safety device.

Info

Publication number: US1027840A
Application number: US66854211A
Authority: US
Inventors: William H Graham
Original assignee: Individual
Current assignee: Individual
Priority date: 1911-12-29
Filing date: 1911-12-29
Publication date: 1912-05-28
Anticipated expiration: 1929-05-28

Description

W. H. GRAHAM, ELEVATOR SAFETY DEVICE.

APPLICATION FILED DEC. 29, 1911.

Patented May 28, 1912.

3 SHBETSSHEET 1.

INVENTOR a 44 [m ATTORNEYS W. H. GRAHAM.

ELEVATOR SAFETY DEVICE.

AEPLIOATION FILED DEC. 29, 1911.

1 ,O27,840. Patented May 28, 1912.

3 SHEETS-SHEET 2.

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V TOR ram/77 ATTORNEYS Patented May 28, 1912.

INVENTOR WITNESSES ATTORNEYS I WILLIAM H. GRAHAM, OF PITTSBURGH, PENNSYLVANIA.

ELEVATOR SAFETY DEVICE.

Specification of Letters Patent.

Patented May 28,1912.

Application filed December 29, 1911. Serial No. 668,542.

To all whom it may concern:

Be it known that I, WILLIAM H. GRAHAM, a citizen of the United States of America, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have in vented certain new and useful Improvements in Elevator Safety Devices, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to a safety device for elevators, and the primary object of my invention is the provision of positive and reliable means, in a manner as will be hereinafter set forth in connection with cable hoisted elevators, for preventing a sudden descent of an elevator cage should the hoisting cables thereof break.

Another object of this invention is to furnish an elevator cage with gripping shoes and the cage guides with stop blocks, said shoes and said stop blocks being automatically actuated to retard and eventually stop the sudden descent of an elevator cage.

A further object of this invention is to accomplish the above results by a mechanical construction that is durable, inexpensive to manufacture, and highly efiicient for the purposes for which it is intended.

With the above and other objects in view, the invention resides in the novel construc tion, combination and arrangement of parts to be hereinafter specifically described and then claimed.

Reference will now be had to the drawing wherein there are illustrated the preferred embodiments of my invention, but it is to be understood that the structural elements are susceptible to such variations and modifications as fall within the scope of the appended claim.

In the drawings like numerals denote corresponding parts throughout the several views, in which Figure 1 is a front elevation of a portion of an elevator shaft in accordance with this invention, Fig. 2 is a vertical sectional view of the same, Fig. 3 is an enlarged side elevation of an elevator cage in accordance with this invention, Fig. 4 is a front elevation of the same, Fig. 5 is a detail perspec' tive view illustrating the arrangement of the hoisting cable, Fig. 6 is an enlarged front elevation of a portion of the elevator shaft, partly broken away and partly in section, illustrating one of the stop blocks, Fig. 7 is a cross sectional view of the same, illustrating one of the hoisting pulleys, Fig. 8 is a front elevation of a modified form of gripping shoe, and Fig. 9 is a side elevation of the same, partly broken away and partly in section.

The reference numerals 1 denote vertical oppositely disposed guides having the con-' fronting faces thereof V-shaped, as at 2. The upper ends of the guides 1 are connected by a transverse beam 3 having a central oblong opening 4:.- Movably mounted within the opening 4: is a housing 5 and journaled in said housing is a transverse pin 6 upon which there is mounted a grooved hoisting pulley 7. The housing 5 has lateral flanges 8 provided with openings 9 and extending through said openings are guide pins 10 that are screwed or otherwise mounted in the transverse beam 3. The guide pins 10 extend upwardly through sockets 11 in the beam 3 and arranged within said sockets and encircling said pin are coiled compression springs 12. The tension of the springs 12 is suflicient to elevate the housing 5 when pressure is released upon the hoisting pulley .7.

To limit the movement of the housing 5, the beam 3 is provided with caps 14. for the guide pins 10, said caps being bolted or otherwise secured, as at 15 to the beam and each cap has a recess 16 providing clearance for the lateral flanges 8 of the housing 5.

Mounted upon the lateral flanges 8 of the housing 5 is an inverted U-shaped yoke 17. Pivotally connected to the yoke 17 by pins 18 are the inner ends of levers 19, said levers being fulcrumed by pins 20 in bearings 21, carried by the beam 3. Pivotally connected to the outer ends of the levers 19 by pins 22 are the upper bifurcated ends of sockets 23 on rods 2a, said rods extending through openings 25 provided therefor in the beam 3 and downwardly at the sides of the guides 1. 7

Throughout the length of the guides 1 there are casings 26 through which the rods 24 extend. The casings 26 are carried by the guides, and within said casings there are pivoted stop blocks 27 that are retained therein by pins 28. The stop blocks 27 are pivotally connected by links 29 to bearings 30, carried by the rods 24. The stop blocks 27 are limited in their movement by stop pieces 31 located within the casings 26. The upper ends of the stop blocks 27 are notched, as at 32 for a purpose that will hereinafter appear.

The reference numeral 33 denotes a rectangular frame around which can be built an elevator cage. This frame will be hereinafter referred to as the elevator cage. Arranged upon the top of the cage 33 is a movable or yieldable housing 34 having lat eral flanges 35. The lateral flanges 35 are provided with openings to receive side'pins 36, carried by the top of the cage. The guide pins 36 are provided with heads or caps 37, and encircling said guide pins, be tween the heads 37 and the flanges 35, are coiled springs 38, said springs retaining the lateral flanges 35 normally in engagement with the top of the cage 33. Revolubly mounted within the movable housing 34 are grooved hoisting

pulleys

39 and 40. Connected to the lateral flanges 35 of the housing 34. are yokes 41 and pivotally connected to said yokes by pins 42 are the inner ends of levers 43, said levers being pivotally mounted or fulcrumed by pins 44 in bearings 45, carried by the top of the cage 33.

Connected to the outer ends of the levers 43 are the upper ends of stirrups 46, said stirrups extending downwardly at the sides of the cage 33.

The bottom of the cage 33 is provided with a transverse stepped depending beam 47, saidbeam having the front and rear sides thereof stepped, as at 48, 49 and 50. The ends of the beam 47 are inclined and provided with dove-tailed inclined grooves 51 and movably arranged in these grooves are gripping shoes 52 having flanges 53 engaging in the grooves 51-. The outer sides of the shoes 52 have vertical grooves, V-shaped in cross section, and the walls of said grooves are provided with teeth 54. The shape of the outer sides of the shoes 52 is such that the shoes can move into engagement with the sides or edges 2 of the guides 1, as will hereinafter appear. The stepped portion 48 is located upon the front side of the beam 47 and the ends of this stepped port-ion are adapted to be engaged by the stop blocks 27. The stepped portion of the beam 47 is provided with a vertical opening 55 to provide clearance for one of the arms of the stirrup 46. The lower ends of the stirrups 46 extend under the stepped portion 49 of the beam 47, and through the gripping shoes 52, whereby the gripping shoes 52 can be elevated by the stirrups 46.

The reference numeral 56 denotes a hoisting cable that passes downwardly under the pulley 39, upwardly over the pulley 7 and downwardly under the pulley 40, said cable having one end thereof anchored or secured to the beam 3, as at 57 and the opposite end thereof connected to a suitable hoisting mechanism, (not shown). The weight of the elevator cage retains the housing 5 lowered and seated upon the beam 3, consequently the stop blocks 27 will be retained in a retracted position through the medium of the levers 19 and the rods 24. The weight of the elevator cage retains the housing 34 normally elevated and the stirrups 46 lowered, said stirrups allowing the gripping blocks 52 to normally remain in a lowered position out of engagement with the guides 1. Should the hoisting cable 56 break, or either end thereof become detached, the sudden release of the elevator cage allows suflicient slack in the hoisting cable for the housings 5 and 34 to shift. The former is elevated through the medium of the springs 12, the levers 19 and the rods 24 actuated, and the notched upper ends of the stop blocks 27 shifted into the path of the off-set portion 48 of the beam 47, whereby the beam 47 Will strike the stop blocks 27 and be prevented from further descending. The movement of the elevator cage, before reaching the stop blocks 27 is retarded by the gripping shoes 52 engaging the guides 1. The gripping shoes 52 are elevated by the stirrups 46 and the levers 43, when the housing 34 is seated upon the cage 33. The sides of the elevator cage have slides 58 and 59 to receive the guides 1.

In Figs. 8 and 9 of the drawings, there is illustrated amodification of the invention, wherein the ends of a beam 60 are cut away to receive the guides l, and the sides .of the guides are provided With longitudinal grooves 61. The ends of the beam 60 have tapering grooves 62 for gripping shoes 63 that are elevated by rods 46 to engage in the grooves 61 of the guides 1. In this man: ner the V-shaped edges of the guides are not injured by the gripping shoes.

l/Vhat I claim is In a safety device for elevators, the combination with guides, a beam carried by the upper ends thereof, a cage slidable between said guides, a hoisting cable for moving said cage, stop blocks carried by said guides and adapted to be shifted into the path of said cage, and gripping shoes carried by said cage and adapted to move simultaneously with said stop blocks and engage said guides, of a normally seated movable housing carried by said beam, a pulley journaled in said housing, a normally unseated housing carried by said cage, pulleys journaled in said housing and together with the pulley of the first mentioned housing receiving In testimony whereof I affix my signature said 1llloiisiting cable, and means for unseatin the presence of tWo Witnesses.

ing t e rst mentioned housin and seating the second mentioned housin g When said WILLIAM GRAHAM a cable is released whereby said stop blocks Witnesses:

and said shoes Will be actuated to retard the MAX H. SROLOVITZ,

movement of said cage. CHRISTINA T. HOOD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. G.