US2234807A - Soaking pit cover handling apparatus - Google Patents

Description

March 11, 1941. E. RAYSOR OAKING PIT COVER HANDLING APPARATUS Filed Dec. 1, 1938 2 Sheets-Sheet 2 ntentcd Mar. ll, 1941 SOAKING PIT COVER HANDLING APPARATUS Earl L. Raysor, Youngstown, Ohio, ossignor to Manning, Maxwell 8: Moore, Inc., Muskegon, Mich, a corporation of New Jersey Application December 1, 1 93%, Serial No. 263,364

Claims.

The invention relates to apparatus for liftinc and displacing heavy objects and has particular reference to improved apparatus for removing and replacing the covers of metallurgical ti furnaces or soaking pits of the floor installed type.

it furnace of the above general character is usually closed by a removable cover adapted to fit over the mouth of the pit and to rest onthe W floor in which the pit is installed. Due to the high temperatures at which such furnaces are.

operated, the covers are generally constructed in the form of a metal frame lined with fire briclt or other suitable refractory material. Such covers are so heavy and bullry that power actuated mechanism is required for handling them.

When a single cover handling device, such as a crane or trolley, is employed in handling the m must he provided for temporarily connecting the lifting mechanism of the device with the various pit covers. The connecting mechanism heretofore available for this purpose has been relative 1y complicated and therefore expensive to install and dimcult to maintain in satisfactory op--' erating condition due to the extremely hard usage to which such apparatus is necessarily subjected.

With the foregoing in view, an important ob- 'ject of the invention is to overcome the above dimculties by providing an mproved soaking pit cover trolley which can be quickly and easily connected with any one of a plurality of soaking pit covers, which is simple and rugged in constructlon, emcient and reliable in operation, and

which is not likely to get out of order.

A more specific object is to provide improved means for establishing a temporary operative dill soaking pit cover trolley and a pit cover so that the cover can be lifted from the pit and transported to one side thereof to giveaccess to the pit and can thereafter be replaced over the pit 45 and disconnected from the lifting mechanism.

Another object is to provide improved lifting mechanism particularly suitable for soaking pit cover handling apparatus. a

- the! objects and advantages of the invention M will become apparent from the following detailed description of the'preferred embodiment illustrated in the accompanying drawings, iii-which: Figure 1is a perspective view of a soaking pit cover trolley embodying the features of the 55 invention. Fig. 2 is a sectional'view of the trolley showing details of the lifting mechanism.

1 Fig: 3 is an end elevation of the connecting ,meansfor establishing a temporary connection go between th'elifting mechanism and a pit cover.

covers of a plurality of soaking pits, some means connection between the lifting mechanism of a While the invention is susceptible of various modifications and alternative constructions, It

have shown in the drawings and will herein de- 5 scribe in detail the preferred embodiment, but it is to be understood that I do not thereby in-. tend to limit the invention to the specific form disclosed but intend to cover all modifications and alternative constructions falling within the lil spirit and scope of the invention as expressed in the appended claims.

Referrihc to the. l of the drawings, t indicates a soaking pit cover closing a pit furnace whose throat t opens in 'a masonry structure it constil5 tutine the door of the furnace room. The cover t, as herein shown, isfabricated from standard steel shapes comprising heavy channel side memhers d reenforced with channel columns l and iii-beams ll. d refractory lining ll of fire briclr no protects the-metal parts of the cover from the heat of the furnace. Flange plates ll, welded or otherwise secured to the side channels it so as to project below the lower edges of the channels, are adapted to ht into a recess it in the floor l encirclhig the mouth of the pit. The recess may be filled with sand or the like to seal the Rails it disposed in recesses it on opposite sides of the pit formatraclr for a trolley 2t 30 which carries apparatus for lifting the pit cover to be described in detail hereinafter. Preferably, the rails it are extended along a row of pits so that the trolley 20 is enabled to serve all of the pits in the row, thus avoiding the necessity of providing separate cover handling apparatus for each pit. In any event, the rails M are extended for enough beyond the pit to permit the cover 5 to be moved laterally sufiieiently to expose the throat 6 of the pit.

The trolley ,20, as herein shown, comprises a, generally rectangular frame consisting of end beams 2| and 22 connected by transverse box girders 23. Journaled on each end beam are ,a

' pair of flanged wheels 2| which support the trolley on the rails ll so that it may be traversed r from a position at one side of the pit to a position directly over the pit. For traversing the trolley relative to the pit, one wheel of each pair is drivingly connected with" a traverse shaft 25 which extends across the trolley and is journaled in suitable bearings 26 supported on cross beams 21 extending between the girders 23. The driving connection between the shaft and the flange wheels may be of any suitable character such as a chain and sprocket drive which, for purposes of safety, is enclosed by a suitable guard or housing 28. A motor 29 mounted on the wheehbeamll is arranged to [drive the shaft 25 through a speed reducer 29a Gil Suitable limit switches may be interposed in the operating circuit of the motor in well known manner to automatically stop the trolley when it is spotted directly over a pit.

The trolley 20 is equipped with suitable lifting mechanism adapted to be temporarily connected with a pit cover for raising and lowering the cover vertically so that it may be transported to one side of the pit or replaced over the pit without injuring the masonry structure around the pit throat. This reduces wear on the pit structure and cover, thus increasing their useful life and materially reducing maintenance expense. Moreover, it permits the use of a sand seal around the cover so that heat losses are reduced to a minimum.

Referring now to Figs. 1 and 2, the lifting mechanism in its preferred form comprises a series of lifting elements herein shown as rockers or bell cranks 3| arranged in pairs at opposite ends of the trolley. Each bell crank is pivotally supported on a cross plate 32 in the associated girder 23 by a pivot shaft 33, The bell cranksof each pair are arranged on a line extending substantially parallel to the path of the trolley to facilitate connection of the lifting mechanism with the pit covers, as will appear presently.

Each of the bell cranks 3|, as herein shown (Figs. 1 and 2), consists of a pair of triangular steel plates 34 and 35 rigidly held in parallel spaced relation by atubular spacing member or hub 36 welded to the respective plates. The pivot pin 33 extends through the hub which is fitted with suitable bearings 31 for the pin.

The bell cranks 3| are arranged to be rocked in unison by common power driven means. To this end, the bell cranks of each pair areoperatively connected with an eccentric 4| keyed to a shaft 42 which extends across the frame of the trolley intermediate the bell cranks forming the several pairs -and is journaled in bearings 43 carried on the cross beams 21. The connection between each bell crank 3| and its associated eccentric is provided by a rigid arm 44 pivotally connected at one end to the bell crank by a pivot pin 45 and having at its other end an eccentric strap 46 encircling the eccentric 4|.

Thus, while the operating arms of the bell crank of each pair are separate and independent parts, they necessarily move together by reason of their connection with a common eccentric. Further, since both eccentrics are keyed to the same shaft 42, all of the bell cranks will be rocked in unison when the shaft is rotated. In order that the bell cranks 3| may rock in the same direction, those located on one side of the frame have the arms 44 connected below the pivotal point of the bell crank, while those located on the other side of the frame have the arm connected above the pivotal point, as shown in Fig.2.

Power for driving the eccentric shaft 42 is supplied by a motor 41 through a speed reducer 41, drive shaft 43, and a suitable gear train enclosed in a housing 43, as shown in Fig. 1. A limit switch of any suitable construction may be operatively associated with the eccentric shaft 42 and adjusted to interrupt the operating circult of the motor 41 when the eccentrics are turned into either of their dead center positions so as to automatically stop the lifting mechanism in the proper position. In one dead center position; the bell cranks are rocked so as to lift the cover the maximum distance from the floor, while in the other position the cover is lowered to the floor. By the use ofeccentrics, the speed reducer and driving gear train is relieved of substantially all strain while a cover is held in either raised or lowered position,

The lifting mechanism is arranged to be operatively connected with the pit cover 5 through the medium of novel connecting means including connecting members 5| (Figs. 2 and 3) carried by the respective lifting elements and arranged to cooperate with gripping members 52 secured to the pit cover. To facilitate such connection, the various members are constructed and arranged so that they may be brought into cooperative association or engaged by movement of the trolley 20 along its track. Disengagement of the members is effected by reverse movement of the trolley. In the exemplary form of the trolley shown in the drawings, four connecting members 5| are provided, one for each bell crank 3|. These members are suspended from the respective ,bell cranks so as to move vertically when the bell cranks are rocked about their pivots.

As shown in Fig. 3, each connecting member 5| .comprises a vertically disposed plate 53 having a reenforced flange plate 54 welded to'its lower edge to form a rigid structure of inverted, generally T-shaped cross section. The connecting members associated with the bell cranks at the right side of the frame (as viewed in Fig. 2) are each formed with a relatively long upwardly projecting extension 55 adapted to be pivotally secured to the bell crank 3| by a pivot pin 55'. The connecting members for the left side of the frame differ from the members above described in that the extension designated as 55 is substantially shorter than the extension 55. The connection between this member and its associated bell crank is provided by a link 56 pivotally connected at opposite ends to the bell, crank 3| and the extension 55 by pivot pins 51 and 58, respectively.

The link connection for the left-hand connecting member of each pair is provided for the reason that the two connecting members are rigidly Joined together by a lifting beam 6| which serves to hold the members in predetermined spaced relation and to maintain the flanges 54 of both members in the same horizontal plane at all times. The lifting beam 6|, as shown in Figs. 2 and 3, comprises a pair of angle bars 62 and 63 arranged back to back on opposite sides of the connecting member plates 53. The vertical webs of the angle bars are welded or otherwise suitably secured to the plates and the bars are additionally connected together at intermediate points by cross members 64 welded to the horizontal webs of the bars.

The gripping members 52, with which the connecting members 5| cooperate, are all of similar construction, and a description of one will therefore suflice. These members are mounted on the pit cover 5 in pairs spaced apart similarto and alined with the pairs of connecting members carried by the trolley. In the particular embodiment illustrated, two pairs of gripping members corresponding to the two pairs of lifting elements are provided, although it will be understood that any number necessary to support the weight of the cover may be employed.

In the preferred form shown in Figs. 3 and 4, the gripping member 52 comprises a pair of inverted, generally U-shaped end plates H and 12.

The upstanding legs of the plates are rigidly conand end plates of the respective structures are a pair of top plates 16 which project partially over the opening 15 and thus form a T-slot for the reception of a connecting member 5|. The -spacing at the top plates 16 is slightly greater than the thickness of the lifting beam 6| so that the beam and connecting members 5| carried thereby may readily be inserted in the slot by endwise movement of the beam incident to traverse movement of the trolley relative to the pit. Further, the adjacent corners of the respective top plates are beveled as at 11 (Fig. '1) so that the connecting members may enter between the plates without danger of catching thereon. When the connecting members are engaged in the gripping members in the above manner, the flanges 54 project under the edges of the top plate 16 whereby to engage the gripping member and cover to which it is attached when the connecting member is raised by operation of the lifting mechanism.

The gripping members 52 may be secured to the cover 5 in any suitable manner so as to enable them to sustain the weight of the cover. As shown in Fig. 4, the members are arranged to straddle the channel columns 9 with the lower portions of the end plates ii and I2 overlying the sides of the channel members. Pins 18 extending through the channels of the column and the depending ends of the members II and I2 hold the gripping member securely in place on the cover. To prevent accidental displacement, the pins 18 are drilled at each end for the reception of headed locking pins 19' carried by angle brackets 19" welded or otherwise secured to the end plates 1| and 12 of the gripping member. The locking pins may be pulled out to permit withdrawal of the supporting pins 15 when it is necessary to remove the gripping members for repairs.

It will be apparent from the foregoing that the invention provides a soaking pit cover handling apparatus of novel and improved construction. The apparatus includes a trolley carrying powerful and efficient lifting mechanism capable of being quickly.and easily connected with any one of a plurality of soaking pit covers. The connecting mechanism, while efficient and reliable in operation, is of simple and rugged construction and not likely to get out of order or to require frequent attention. The work of the operator is greatly simplified since the connection of the lifting mechanism with a pit cover may be effected as an incident to the traverse movement of the trolley from a position of one side of the pit to a position directly over the pit. Disconnection of the lifting mechanism from the cover is likewise eifected by the traverse movement of the trolley, the lifting mechanism being in its lowered position during, such connecting and disconnecting movements.

, I claim as my invention:

1. The combination with the lifting mechanism ofa soaking pit trolley, of connecting means for operatively connecting the mechanism with a pit cover, said connecting means including a pair of vertically disposed plates, 9. flange plate rigid with the lower edge of each vertical plate and forming therewith an inverted generally T-shaped connecting member for cooperating with a gripping member on the pit cove and f, a rigid beam secured to said vertical plates operativeuto hold the connecting members in predethe plates and lift over the central opening termined spaced relation and to maintain the flange plates thereof in the same plane in all positions of the lifting mechanism.

2. Connecting means for operatively connecting the lifting mechanism of a soaking pit trolley with a pit cover, said connecting means comprising, in combination, a pair of vertically disposed plates, a flange plate rigid with the lower edge of each vertical plate and forming therewith an inverted-generally T-shaped connecting member adapted to engage a cooperating grippingmem;

her on the pit cover, and a pair of elongated bars arranged on opposite sides of said vertical plates and rigidly secured thereto, said bars acting to hold the connecting members in predetermined spaced relation and to maintain the flange plates thereof in the same plane to facilitate engagement of the connecting members with the gripping members of the cover. 3. The combination with a lifting mechanism including a pair of pivoted rockers, of connect ing means for operatively connecting the mechaone of the rockers, an extension on the other of said verticalplates, and a link pivoted at. onev end to said last mentioned extension and at the other end to the other of the rockers.

4. A gripping member attachable to the cover of a soaking pit and adapted for engagement with the T-shaped connecting member of a cover lifting mechanism, said gripping member comprising, in combination, a pair of generally U- shaped end plates, side plates connecting the legs of said end plates opening, and top plates rigidly secured to the upper edges of said side plates with their respective inner edges projecting over said opening to form an inverted T-slot for the reception of the connecting member.

-legs of the end plates to form a pair of rigid box-like structures disposed on opposite sides of a central opening, said structures resting on the cross member of the pit cover with portions .of said end plates depending on opposite sides of thecross member when the gripping member is assembled with a cover, top plates rigidly secured to the upper ends of said box-like structures with their respective inner edges projecting to define a T-slot for the reception of a connecting member, and an elongated pin extending through the depending portions of said end plates and the member of the pit cover for detachably securing the ripping member to the cover.

I L. RAYSOR.

to form rig d box-like struc-- tures disposed on opposite sides of a control

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