US2503954A

US2503954A - Arrangement in mining elevators

Info

Publication number: US2503954A
Application number: US5307A
Authority: US
Inventors: Lindahl Gunnar
Original assignee: ASEA AB
Current assignee: ABB Norden Holding AB
Priority date: 1946-12-31
Filing date: 1948-01-30
Publication date: 1950-04-11
Anticipated expiration: 1967-04-11

Description

A ril 11, 1950 G. LINDAHI. 2,503,954

ARRANGEMENT IN MINING ELEVATORS Filed Jan. 30; 1948 I-LF 2 7 m I r l- -ilq 9 Patented Apr. 11, 1950 ARRANGEMENT IN MINING ELEVATORS Gunnar Lindahl, Vasteras, Sweden, assignor to Allmanna Svenska Elektriska Aktiebolaget, Vasteras, Sweden, a Swedish corporation Application January 30, 1948, Serial No. 5,307 In Great Britain December 31, 1946 Section 1, Public Law 690, August 8, 1946 Patent expires December 31,1966

1 Claim. (Cl. 187-75) In mining elevators it is generally necessaryto arrest the cage at various levels in order to make it possible to move the ore waggons into or out of the cage, as the track in the case must be at the same level as the outside track in order to facilitate transfer of the waggons. In order to give the cage the right position, hooks have heretofore been employed which have been projected into the shaft before the cage is lowered on to them. The projecting out of these hooks is performed by the worker, who has to move the ore waggons at the different levels into or out of the cage, or to supervise this work. It is, however, of the greatest importance that these hooks do not project into the shaft at other levels than at the level where the elevaor is intended to stop, because, if they should project into the shaft at any other place, they would be struck by the cage, possibly when travelling at a high speed, thus causing a serious accident, resulting in considerable damage. It is therefore of the utmost importance that the hooks be removed immediately after they have been used. Hitherto it has been the responsibility of the worker to avoid leaving any hooks projecting into the shaft at places other than at the level at which the elevator is intended to stop. Accidents can also occur, however, if, due to a mistake on the part of the hoist operator, the

elevator is not stopped at the intended level. A certain degree of security can be attained by a signal device from the hooks up to the operator, in his control room so that he may see, which hooks project into the shaft. The disadvantages of this arrangement are that one is dependent upon the alertness of the host operator, and that an individual signal for the hooks at each level is necessary thus involving a rather com-- plicated signal system.

The present invention has for its object to provide an arrangement in which a high degree of security is attained aga nst the above mentioned accidents. According to the invention this security is attained by an arrangement, which allows the projecting out of the hooks to occur only when the elevator, in the act of stopping, reaches a predetermined low speed. The arrangement may be such that the worker, who has to perform the projecting out of the hooks,

only prepares this motion, whereas the motion itself is performed by means of a pneumatic or an electromagnetic device when this low speed has been reached, or the hooks may be operated by hand but remain locked until the said low speed has been reached,

On the drawings,- Figs; la and 1b show'one form of the invention, Fig. 1a showing the hooks withdrawn from the shaft, and Fig. 1b showing the hooks projecting into the shaft. In the shaft, before the levels, counted in the moving direction of the cage, a member I is'arranged which is actuated by the cage and then closes the current over a contact I2 for a time lag relay 2 which, in turn, after a predetermined time closes the operating circuit for the electrically operated air valve 3 for a pneumatic device I4 serving for the projection of the hooks 9. The time lag of the time lag relay is so large that if the speed of the cage is sufliciently high it can pass the said member I before the said prede-' termined time has elapsed so that the time lag relay cannot close the operating circuit and the projecting of the hooks into the shaft is thus avoided. The upper contact of the time lag relay is a holding contact coupled in parallel with the contact I2 which has for its purpose to prevent the halting of the projecting motion of the hooks after it has commenced. The preparation for the projecting of the hooks into the shafts is performed by movement of the member I out into the shaft so that it may come in contact with the cage. This member may for instance comprise a swing arm 5 which by means of an operating lever 4 can be swung into the shaft so far that a spring antenna II attached to the outermost end of the arm can be actuated by a rim It on the cage and thus is turned relatively to the arm so that a contact is actuated. This antenna may for instance be joined wih a curve segment 6 which actuates the operating arm of a contact or also may the contact device consist of a contact attached to the shaft of the antenna, which contact, when the shaft is turned, is brought in contact with a contact attached on the arm. In order to avoid damage to the antenna when the arm is projected into the shaft if the cage should be immediately before the antenna, it is suitably made of spring construction. The curve segment 6 is so designed that when the cage comes from above and acts on the antenna II, the roll I3 outside the periphery of the curve segment 6 is turned a little. When the cage comes from below, the roll will be in contact with the curve segment the whole time. The slot I! in the link I8, in which a bolt of the operating lever 4 runs, is provided in order that it is possible to move the operating lever 4 from the position shown in Fig. 1a to the position of Fig. 1b, when the arm 5 with the antenna II is swung out into the shaft in order to prepare for the projection of the hooks 9. The length of the slot is such that the withdrawal of the hooks, which is performed byhand ,by means of the pperating lever 4, can be performed without any play and so that the projection can be performed without the link acting on the operating lever. When the projection is performed, on ,the one hand 12h? arm 2|] acts on the contact 19 and opens it so that the current to the time lag relay 2 and the coil of the air valve 3 is internuptediand the latter by means of the spring force returns to the original position. On the pther hand, the curve segment 22 acts on the contact I over the roll 21 which contact interrupts the current to the signal lamp in the control room of the hoist operator which lamp when it burns shows that all hooks in the shaft are withdrawn.

I claim as my invention:

Arrangem nt o a esting mining el cages at predetermined levels in their shaft, comprising hooks projecting into the shaft, a member preparing for the projection of the hooks, a nock operating member, ,a lagsm mber controlling said operating member, a member actuated by the cage and acting on said time lag member, said cage-actuated member being mounted in the shaft at a distance above said hooks, a hand-operated "lever acting simultaneously on said hook projection preparing member and projecting said cage-actuated member into the shaft.

GUNNAR. LINDAHL.

REFERENCES GITED :following references are of record in the