US1653909A - Safety - Google Patents

Description

Dec. 27, 1927. 1,653,909

F. HYMANS SAFETY APPLIANCE Filed May 17. 1926 VENTOR l T M IN ATTORNEY Patented Dec. 27, 1927.

UNITED STATES PATENT OFFlCE.

FREDERICK HYM'ANS, OF YGNKERS, NE'vV YORK, ASSIGNDR TO OTIS ELEVATOR COM- PANY, O1? JERSEY CITY, NEW JERQEY, A CORPORATION OF NEW JERSEY.

SAFETY AEILIANCE.

Application filed. May 17,

The invention relates to safety appliances and particularly to safety appliances for elevators.

In elevator operation, it sometimes happens that the car, due to loss of control or other causes, may continue past a terminal landing without stopping. Under such conditions, the descending body is stopped by the operation of its buffer. The ascending body may continue in motion, however. after the descending body has been brought to rest owing to its kinetic energy and that of its connected hoisting ropes. Slack will thus develop in the hoisting ropes and permit the ascending body, upon coming to rest, to fall back. By the time that this slack in the hoisting ropes has been taken up, this falling body will have developed considerable kinetic energy, with the result that the other body will be jerked upwardly, causing serious stress in the hoisting ropes in bringing the falling body to a stop. This would result in considerable discomfort and possible injury to the passengers due to the sudden stopping of the car, in the event that the car is the falling body, or due to the fact that the car is suddenly jerked upwardly by the counterweight, in the event that the counterweight is the falling body. Furthermore, such operation may resuit in damage to various parts of the elevator apparatus.

The principal object of the invention resides in preventing the falling of a body which has continued in its upward movement after the descending body has been brought to rest.

One feature of the invention is the provision of a safety appliance which operates to catch and prevent the falling of the counterweight, in the event that it continues in its upward movement after the car has been brought to rest.

Another feature is the provision of a safety appliance which operates to catch and prevent the falling of the car, in the event that it continues to ascend after the counterweight has been brought to rest.

Still another feature is the provision of a safety appliance of the above character which is of simple construction. reliable in operation and which may be operated an unlimited number of times without replacement.

Othe features and advantages will he 1926. Serial No. 109,688.

come apparent from the specification, taken in connection with the accompanying drawings wherein one embodiment of the invention is illustrated.

In the drawings: 1

Figure l is a schematic representation of an elevator system illustrating the adapta" tion of the safety appliance to both the car and the counterweight; Figure 2 is a view in partial section taken along the line 22 of Figure 1; and Figure 3 is a view in partial section, taken along the line 33 of Figure 2.

Referring to Figure 1, the elevator car is designated by the numeral 1 while the counterweight is designated by the numeral 2. 3 designates the hoisting cables for the car and the counterweight, these cables pass ing over the hoisting drum 4: at the top of the elevator shaft. This drum is driven by means of the hoisting motor 5 to effect the raising and lowering of the car and counterweight. 6 designates an electromagnetic brake for bringing the motor, and therefore the car and counterweight, to a stop. The buffer 7 for the elevator car is 'llustrated as positioned at the bottom of the elevator shaft. The counterweight buffer 8 is illustrated as carried by the counterweight itself, The guide rails for the elevator car are designated 10, while those for the counterweight are designated 11. The bottom guide shoes for the elevator car and for the counterweight are designated 12 and 18 respectively. The top guide shoes for the car are indicated by the numeral 14 and those for the counterweight by the numeral 15. These guide shoes are of diiferent construction from their corresponding bottom guide shoes. The purpose of this modified construction will be seen as the description proceeds. l According to the preferred arrangement. a crosshead 16 is arranged near the top of the elevator hatchway, being normally supported by lugs 17 secured to the car. guide rails 10. This crosshead consists of two opposing channel ineinbers 18 and 20 which span the guide rails 10 and are joined at their ends by connecting members 21 and 22. These connecting members are of similar construction and are secured to the channel members as by screws 23. The construction of one of these connecting members, i. e., member 21, is illustrated in 9; and

This member is slotted, as indicated at 24, so

as to embrace the sides of the car guide rail.

The dimensions of this slot are such that the member has a sliding fit on the rail, thus constituting a guide for the left end of the crossliead. The connecting member is also formed with a pocket 25, extending from one side of the slot. Opposite the slot, this pocket is formed with an inclined surface 26. A roller 27 is arranged within this pocket, this roller being mounted on a shaft 28 carried by the arms of a forked member 30. A shank 31 on the forked member projects loosely through an aperture 32 in the connecting member and has a retaining nut 33 locked on its lower end as by a cotter pin. Theportion of the shank within the pocket is surrounded by a compression spring This spring urges the forked end of member 30 upwardly and towards the narrower part of the pocket. The roller is thus held yieldingly at one side against the inclined surface of the pocket and at the other side against the side of the guide rail. A plate 35 is secured to the outer surface of the connecting member and covers the pocket, thus serving to exclude dirt and foreign matter therefrom; The connecting member 22 is constructed in a similar manner, being preferably arranged so that the pocket is on the reverse side of its guide slot. The inner or opposing surfaces of the connecting members are inward- 'ly inclined from the vertical and terminate in projecting ears 37 and 88, the purpose of which will appear later.

' As previously indicated, the top guide shoes let for the elevator car are constructed differently from those for the bottom of the car. Each of these shoes are provided with a web i0 for pivotally supporting the hook members ii and 42. The hook member s1 is forked at the bottom so as to extend over its web 40, being pivoted by the shaft 48 extending through the forked ends and web. A lug d4 extends from the forked. ends of the member toward the center of the car. A compression spring 4-5 extends between seats formed on this lug and a boss 46 on the guide shoe. This spring tends to maintain the hook member against a stop t? formed by the extended portion of the web d0. The hook member 42 is similarly pivoted on the web &0 of its guide shoe as by shaft 48. A

compression spring 50, acting between a lug 51 and the boss 52 on the guide shoe, positions the hook member against the stop 52!.

The counterweight safety appliance is constructed in the same manner as the car safety appliance above described. A crosshead 54 is mounted on the counterweight guide rails 11 near the top of the hatchway and normally rests on lugs 55 projecting from the guide rails. The ears formed on the connecting members are designated 56 and 57. The hook members and 60 are pivotally mounted on the webs formed on the top counterweight guide shoes The compression springs for these hook members are designated 61 and 62.

During normal operation the car and counterweight are brought to rest upon the deenergization of the hoisting motor 5 and the application of the brake 6. The car safety appliance is so positioned. as not to be operated when the car, moving upwardly, is brought to astop as it arrives at the upper terminal landing. Similarly, the counter weight safety appliance is so positioned as not to be operated when the car, moving downwardly, is brought to a stop at the lower terminal landing.

It sometimes happens, however, that the car continues past the terminal landings without stopping. This may result from various causes but is generally due to faulty operation of the control system. Thus the car may continue for a sufficient distance beyond its upper terminal landing to cause the engagement of the counterweight buffer '8 with the bottom of the hatchway. This results in the counterweight being brought to rest. The car, however, may still possess considerable kinetic energy at the time the counterweight is brought to a stop and, as a result, may continue in its upward move ment. Also, the kinetic energy of the hoisting ropes constitutes an additional force urging the car upwardly. As the kinetic energy of these moving parts varies as the square of their velocities, it will be seen that, in the case of high speed installations, the distance which the car may move may amount to several feet.

As soon as the car comes to rest, it will start to descend owing to the influence of gravity. If the car safety appliance were not provided, the car would develop considerable kinetic energy during its falling movement with the result that, upon the slack which had developed in the hoisting cables being taken up, the counterweight would be jerked upwardly causing serious stress in the hoisting ropes and other apparatus in bringing the car to a stop. Not only would such condition be undesirable because of the possible injury to various parts of the elevator apparatus but also because of discomfort and possible harm to passengers.

With the car safety appliance provided however, if the car continues in its upward movement after the engagement of the counterweight buffer, the hook members il and 42 will engage and slide upwardly on the inclined surfaces of their respective connecting members 21. and 22, the springs lf) and 50 yielding to permit the movement of lit" the hook members about their pivots If this upward movement of the car is above a predetermined amount, the hook members will be snapped over the projecting cars 37 and 38 of the connecting members by the action of springs and as the hook menu bers pass oil the inclined surfaces. Any further movement of the car will cause the topguide shoes 14; on the car to engage the connecting members, causing the crosshead 16 to be carried upwardly by the car. ing the time that the crosshead is ascending, each of the rollers 27 will tend to remain in the Wider portion of its pocket, these rollers simply riding on the guide rails without offering any appreciable resistance to the movement of the crosshead. At the instant that the car is brought to rest, however, each roller will be in engagement with both the inclined surface of its pocket and the guide rail. As the car starts to fall, it will act through the hook members 37 and 38 to'tend to move the crosshead downwardly. The rollers 27, however, will immediately act to Wedge between the inclined surfaces of their respective pockets and the guide rail to prevent any material downward movement of the crosshead, Thus the car will be brought to a smooth and easy stop. As the car has just started on its downward movement, at the time that the wedging action occurs, the rollers will not be jammed and no scarification of the parts will result. It is to be understood that, once the hook members have snapped over the ears of their respective connecting members, the safety appliance operates to prevent the falling of the car regardless of the distance upwardly it may travel.

The car may also continue past its lower landing to the extent that it engages its buffer 7. Although the buffer will cause the stopping of the car, the counterweight may continue in its upward movement for a considerable distance before it comes to rest. Thus, if the counterweight safety appliance were not provided, the counterweight may develop considerable kinetic energy during its falling movement with the result that, upon the slack which had developed in the hoisting ropes being taken up, the car would be jerked upwardly causing dangerous stress in the hoisting ropes in bringing the counterweight to a stop. This condition also would cause discomfort and possible injury to the passengers and might result in damage to the elevator apparatus.

The counterweight safety appliance, however, acts under these conditions in the same manner as described for the car safety appliance when the car overruns its upper terminal landing. The hook members 58 and 60 are snapped over the projecting cars 56 and 57 by the action of springs 61 and 62 as the counterweight moves upwardly. As the Due.

counterweight starts to descend, it acts through the hook members to tend to move the counterweight crosshead downwardly. As a result, the counterweight-is brought to a smooth and easy stop, due to the wedging action of the counterweight crosshead rollers. The position of the various parts of the elevator system, with the counterweight brought to rest by the action of its safety appliancmjs as illustrated in Figure The safety appliances may be released. manually. it is to be understood. that either the car safety appliance or the counterweight safety appliance may be omitted if desired.

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

lVhat is claimed is:

1. An elevator system comprising, two relatively movable bodies in the hatchway, a traction sieave, hoisting roping passing over said shea e and connecting said bodies, thus causing opposite movement of said bodies upon rotative movement of said sheave, means for stopping the descending body as it reaches its lower limit of travel, and means for permitting free upward movement of the ascending body, after the initiation of the operation of said stopping means to stop the descendingbody, until said ascending body is stopped by the action of gravity and for thereupon catching the ascending body to prevent itsfalling.

2. An elevator system comprising, two relatively movable bodies in the hatchway, a traction sheave, hoisting roping. passing over said sheave and connecting said bodies, thus causing opposite movement of said. bodies upon rotative movement of said sheave, means for stopping the descending body at its lower limit of travel before the ascending body reaches its upper limit of travel, and a safety appliance positioned to be engaged by said ascending body after the initiation of the operation of said stopping means, said safety appliance permitting free upward movement of the ascending body after its engagement thereby until. said ascending body is stopped by the action of gravity and for thereupon catching the ascending body to prevent its falling.

3. An elevator system comprising, two

relatively movable bodies in the hatchway, a buffer engaged to stop the descending body as it reaches its lower limit of travel, spring pressed hook members pivotally mounted on said other body, guide rails for said other body, and a safety crosshead supported on said rails near the top of the hatchway to be engaged by said other body in the event that it continues to ascend after the stopping of the descending body, said crossheed comprising a catch member "for each of said hook members and disposed in the path thereof, said hook members engaging and snapping over their respective catches during said continued ascent of said other body, said crosshead further comprising means for permitting its free upward movement after 10 movement of said crosshead and other body after the other body comes to rest.

In testimony whereof, I have signed my 15 name to this specification.

FREDERICK HYMANS.

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