US1715159A - Retiring cam - Google Patents

Description

May 28, 1929.

w. BRUNS RETIRING CAM Filed Oct. 27, 1927 iii-777751 6 A /0 :J 77 M66 6 INVENTOR' Y E N R 0 w A WM @AMKL.

latent ed may I k i i UNI-TED STATES PATENT (OFFICE.-

WILDIAM BBUNS, OF YORK, Y., ASSIGNOR TO OTIS ELEVATOR COMPANY, OF

' NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

nnrmme our.

Application ma October-27, 1927. Serial No} 229,175

r This invention relates to retiring cams 14. as clearly shown in Figures 2 and 3. and particularly to retiring cams for use A pa1r of triangular levers are pivotally i l t stem 4 supported at their apexes on the upper por- In the operation of elevators it is frequenttron of plate 13 by means of a pin 16. A 5 ly desirable to operate door locks, door closer s milar pair of triangular levers 17 are. in engines, and the like from the elevator car. like manner fpivotally supported on the low- To accomplish this a retiring cam may be e por lon o plate 13 by means of a pin 18. mounted on the elevator car for coopera- The triangular levers constitute, in efiect, 'tion with the devices at the various landings. right angle bell cranks with their fulcrums 10 When the elevator car is running, the re- ,at the pivotal supports 16 and 18. Collars tiring cam is retracted so that it clears the 20' serveto space the triangular levers of devices located in thehatchway and when each pairjfrom each other, and collars 21 the car stops at a landing, the-retiring cam serve to space/each pair of triangular levers is extended to operate the devices .at that from plate 13. Cotter pins 19 hold the le- 15 l di vers securely in position. A cam plate 22 is One feature of the invention is the proprovided with two supporting arms 23 rigvision of a retiring cam that exerts a conldly secured to the cam plate by riveting over stant operating force as it moves from its portions 24 of arms 23. Two supporting retracted position to its extended position. arms 23 of the camplate are pivotally con" '20 A second feature ofthe invention is the nectedto corresponding vertices of trianguprovision of a retiring cam that occupies lar levers 15 and 17 by means of pins 25. a minimum of space, and requires a mini-. A cam weight 26 is pivotally connected to mum of force to operate. it. correspond ng vertices of triangular levers v A third feature of. he invention is the 15 and 17 by means of pins 27.. Cam 25 provision of a retirin cam that is of simweight 26 is provided with recesses 29 ple, compact and stur y construction, reliatoaccommodate the triangular levers. By

' ble in operation, and which may be operthis construction downward movement of the ated an unlimited number of times without weight causes the triangular levers to swing replagement y about their supporting pins-and move the 30 Other features and advantages will become .cam to its extended position.

apparent from the following description and" Aretiring cam magnet 28 for moving the appended: claims. i caminto itsretracted position is adjustably I th drawings: mounted upon the car 10. The construction Figure 1 illustrates the retiring cam apof themagnet is clearly shown in Figure 4. 35 plied to an elevator car and shows the cam The magnet is provided with a coil 30 and in its retracted position; an armature 31, the armature being pivotally Figure 2 is a view in frontelevation of connected to the magnet frame by means of the retiring cam in its extended position; a pin 32. A. dash-pot, which serves both to Figure 3 is a view in side elevation of the limit the movement of armature 31 and to 40 retiring cam with portions .broken away to retard its motion in one,' direction, is supillustrate certain structural details; ported by the magnet frame. ,-A dash-pot Figure 46 is a view in part'se'ctlonal elecylinder 33 is formed integrally with the vation of the cam' operating magnet; magnet frame, although 'it may be formed Figure 5 is a view in front elevation of 'a as a separate element. A piston 34;. is

45 modification of the retiring cam in its explaced within the cylinder 33 for reciprocat- 1'00 tended position; and a ing movement. Piston rod 35, which is piv- Figure 6 is a view in side elevation of the otally connected to piston 34, is provided modification of the retiring cam with porwith a rod 36 screwed into-itsend. Armations broken away to illustrate certain structure 31 is operatively connected to rod 36 50 tural details. by means of a pivot pin 37,- the pin being Referring to Figure 1, an elevatorcar 1O bored to accommodate rod 36. Piston rod is provided with a retiring cam 11 arranged 35 serves as one abutment for armature 31 to operate a ooor lock operating lever 12. and nuts 38 as the other abutment. Buffer -Retiring cam 11 is provided with a plate 13 springs 40 are placed between the armature" '55 securely fastened to elevator car 10 by screws and the .abutments to lessen the impact of no the armature as it swings from one abutment to the other to move the piston. A

lbell crank 41 is ,pivotally supported by car 10, one arm 42 of the bellcrank being connected to cam weight 26 by .a chain 44, the

other arm 43 of the bell crank being pivotally connected to armature 31 by means of a I rod45.' The point. at which rod 45 is connected to armature 31 maybe varied by changing the pivotal connection ofrod 45 from one to another of holes 46'. The motion of piston 34 in its inward movement is limited by the end of the dash-pot cylinder and in its outward movement, by dash- .pot cylinder head 47. Rubber washers '48.

are provided to absorb the impact caused by piston '34 being broughttoa stop at the ends I of its movement; A ball check valve 50- is screwed into passage 52,- the passage 52'be'- f ingconnected with the inter1 or,of the cylinder by means of passage 53. An ape'rtured plug 55 is screwed into the end of. passage y The operation of the retiring cam -1S as follows:

Assume the car to be at .a landing asshown in Figure 1 and magnet 28 to be energized. The magnet, acting through rod 45,

a bell crank 41 and chain 44, holds cam weight 26"at its upper position, thus holding cam 'plate 22 in its retracted position. To cause cam plate '22 to operate lever 12, the magnet is deenergized, permittin -26 to -move downwardly P11111110- the chain cam weight.

ownwardly withit. As the weight moves itswings triangular levers 15 and 17 about their ivotal supports to force cam :plate 22 into its extended position. At the same time, armature 31' swings to its outward position and as it approaches the end -,0f 1tS outward movement it-engages buffer spring 40, causing piston 34 to moveto. the right as viewed in Figure 4. The iston upon engaging head 47, through ru ber washer 48, stops the weight in its downward movement. A stop '56, provided with a buffer spring 57,;is supported: upon plate 13 by l'iV- eting over. pro ectin portion 58 ofstop 56,

the stop serving .un er any circumstances to prevent excess downward movementpf the. cam weight. The weight is gentlybrought to a stop by the suction created'in the dash-.

' apertures, .within passage engagesbufier spring 40 allows a rapid-expot as the piston movesto-the ri ht. The

rce of thissuction ma be varied y inserting plugs, formed wit larger or smaller Themirestricted movement of the armature before it tension of cam plate 22, while the dash-pot acting at. the end of the armature. movement prevents weight26 from. being broughtto a stop too suddenly.

To retire cam .plate' 22, the, magnet is again* energized causing the armature swing to its inner position.--;We1gh t 26 is lifted position swinging triang ularlevers 15 and 17 about their pivots,

causing the cam plateto moveiinto. itSFIB tracted' position. The armature in swing- 1 ng lnward-ly engages buffer spring 40, causmg p1ston34 to moveto' the left as viewed in Figure l. The piston upon engaging the 1 end of the cylinder stops weight 26 initsup ward movement. Stop 56 againacts. as a safety to prevent excess upward movement. The movement of'the piston to the left is substantially unretarded but this may be governed: by varying the sizeof the ball check valve employed.

Referring toFigures 5 and cam-1s illustrated in which a spring, instead of a weight, is used to move the cam plate to its extended position. A plate 60' is securely fastened to car 61 by means of screws 62. Triangular levers 63 are pivotally supported on the upper portion .of plate 60-and trian 'gular levers 64 are 'pivotally supported on.

the lower-l'portion ofplate 60. A cam plate 65,:provided with rigid projecting arms 66, is plvotally supported at corresponding-vet 6, a retiring El) tioes of tnangularlevers"63 and 64 by pins .67. far the structure isfidentical with that lllustratcdjin'Figures 2 and 3. Howv ever, of the weight, a bar 68 is used" i to connect corresponding vertices-7O of the triangular levers.v A U-shaped bracket 71 is secured to bar 68 hy means of a screw 72. A rod 73 1s pivotallyconnected at one end to;

bracket 71 by pin74 and is guided at its magnet, bar 68 is pulled toits upper position I against the compression of spring. 7

Upon deener'gization of. the magnet, the spring," with bracket '75 as an abutment, acting-agamst seat 76. forces bar 68 to'i-ts lower position,.causing'triangular levers 63 and 64 7, movmgjcam-plate 65 to its retracted position. no

to move -about their pivotal. supports. As '1 the levers so move, cam plate 65 is forced into its extended-position.

= n is to be noted that with' the retiring cam of,this invention,- as illustrated in Figure .1 the force exerted in .ahori'zontal direcm.

6y the cam'plateis constant throughout.

tion its movement from retracted to extended 'tion. .As the weight falls under the in-.

uenoe of .gravi all? acts. through" the bell crank levers toove the cam plate. Thus,

' the arms ofi the bell crank lever 'to .be'of equal length,the vertical component of the movement of the cam weight is equal to the horizontal component of the movement of the cam plate. Then since the: cam 139 plate; actuating Weight constant, the force that the cam plate may exert in a horizontal direction is also constant.

In the case Where a spring is employed, substantially the same results are obtained provided the spring is of suflicient length and under sufficient initial compression.

Attention is called to the fact that as tlie force exerted by the cam is constant, it is only necessary to design a cam so that this constant force will overcome the maximum opposing force, and .it makes no difference in What portion of its movement the cam contacts with the element to be moved or operated.

As many changes could be made in the above construction and many apparently widely dilferent embodiments of this invention could be made without departing from the scope thereof, it is intended that all mat ter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. I

What is claimed is:

1. A retiring cam comprising; a cam means for moving thecam plate to its extended position; a substantially right angle bell crank lever connecting said cam plate and said actuating means; and retarding means brought into action as the cam plate nears its extended position to cause a gradual stop of said cam plate and actuating'means.

angle bell crank lever,

2. A retiring cam comprising; a support; a cam plate; a cam Weight for moving said cam plate to its extended position; a right fulcrumed on said support, and. connecting said cam plate and said cam weight; a dash-pot; and a lost motion connection between said cam weight and dash-pot to cause the operation of the dashpot just before the cam plate reaches its extended position to. bring said cam plate and Weight to a gradual stop.

3. A retiring cam comprising; a support; a cam plate; a cam weight for moving said cam plate to its extended position; a pair of right angle bell crank levers, fulcrumed on said support, and connecting said cam plate and said cam weight; a member connected to said weight to be moved thereby about a pivot during extension of said cam plate; a daslnpot having an extended piston rod; and a butler spring arranged on said rod in the path of movement of said member about said pivot, said spring being spaced from said member when the cam plate is in retracted position to allow rapid extension of the cam plate and upon engagement by said member just before the cam plate becomes fully extended causing the operation of the dash-pot to to a gradual stop.

In testimony whereof, I'have signed my name to this specification.

WILLIAM BRUNS.

bring the Weight and cam plate

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