US1766556A - Well tool and appliance - Google Patents

Description

93@ N. K. SMITH 1,765,556

WELL TOOL AID APPLIANCE Filed March 24, 1925 3 Sheets-Sheet l June 24, 1930.

N. K. SMITH WELL TOOL AND APPLIANCE 3 Sheets-Sheet 2 Filed March 24, 1925 C a 6 A .M m M5 4 M d M u x/( Il@ 3 7 B 4 JNVENTOR, n

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Patented June 24, 1930 UNITED STATES NELSON K. SMITH, OF LOS ANGELES, CALIFORNIA., ASSIGNOR TO BYRON JACKSON PATENT oEFicE F 'WEST BERKELEY, CALIFORNIA, A CORPORATION OF DELAWARE WELL TOOL AND APPLIANCE Application led March 24, 1925. Serial No. 17,901.

This invention relates to well tools and appliances and more particularly to devices for elevatin and lowering and otherwise handlin tu ing, casing, pipe, and sucker rods uti ized in the drilling and casin off of wells and the pumping of fluids t erefrom.

The invention has for an object to provide an improved tool or appliance of the general character stated, which will be relatively simple in construction and which will depart from and be an improvement over simifar devices heretofore produced with respect to facility and convenience in manipulation and handling and use, positiveness and eiectiveness in operation and service and length of life or durability, and adaptability under `a wide range o conditions of service, andwhich will be generally superior in efficiency and serviceabjlity. l

With the above and other objects in View the invention consists in the novel and useful provision, formation, construction, combination, association and'f'inter-relation of 95 parts, members and features, all as here1nafter described, shown in the drawings, and A designated by the same reference characters.

finally pointed out in claims.

In the drawings: Figure 1 is a front elevation of an elevator device constructed and organized to embody the invention; y' Figure 2 is a top plan view` thereof; Figure 3 is a vertical fragmentary sec tional view thereof, taken upon the line 3 3, Figure 2, and looking in the direction of the appended arrows;

Figure 4 is a further detail vertical fragmentary sectional view, taken lupon the line v 1 -4, and looking in the direction of the appended arrows; l

Figure 5vis a similar view of a modified form ofthe construction illustrated in Figure 4' Figure 6 is a similar view of a modified form of thellconstruction shown in Figures 4 and 5; Figure 7 is a similar view of a modified form of the construction shown in Figures 4, 5 and 6;

Figure 8 is a similar view of a modified form of construction in departure from the showing of Figures 1 and 2, and is a fragmentary vertical section taken on the line 8 8, Figure 2, and looking in the direction of the appended arrows;

Figure 9 is apfragmentary vertical sectional view taken through either the body or the closure or gate shown in Figures l and 2;

FigurelO is a view similar to Figure 9 of a modified form of construction;

Figure 11 is a View similar to Figures 9 and 10 of a still further modified form of construction Figure 12 is a view similar to Figures 9, l0, and 11 of a still further modified form of construction v Figure 13 is a detail horizontal lfragmentary enlarged sectional view taken upon the line 13-13, Figure 1, and looking inthe direction 'of the appended arrows; and,

Figure 14 is a detail fragmentary vertical sectional view taken upon the line"14-14, Fig. 2, and looking in the direction of the ap ended arrows.

orresponding parts in'all the figures are Referring with particularity to the drawings, I have shown in Figures l and 2 at A the main body of an elevator device constructed to embody the invention in one form, and at B a closure or gate or member cooperating with the member A to confine or embrace between it and said member A the tubing, casing, pipe, sucker rod -or other device or object to be handled or elevated or lowered. The main body A has lateral projections a: for engagement by orconnection with suspension means (not shown) to that end being bifurcated as clearly shown in Figurefl, but only incidental to the features of the invention of this case. In the form of construction shown the gate or closure B is hingedly associated with the body A, as at b, said gate to that end having a knuckle 15 received between knuckles 16 on the body, the knuckle-15 being reduced in height so as to permit vertical play of the gate as an entirety in the manner and for the purposes hereinafter pointed out. l.

C designates latch means between the gate and body for maintaining the gate in closed position. D, best shown in Figure 3, designates means whereby the outer or free en s of the gate and body cooperate to interlock said ends. s E designates anti-friction means effective as between the gate and vthe body in the embodiment of the gate in either closing or opening direction; F in Figure 5, G in Fi ure 6 and H in Figure 7 designate modified forms of the construction of means E.

K in Figure 8 designates a modification of the hinge means 'b of Figures 1 and 2. L indicates an intruding portion at the top of each the body and gate, whereby the internal bore of the device is somewhat reduced at that zone of the elevator. M in Fi ure 9, N in Figure 10, O in Figure 11, and in Figure 12 designate further internal projections or intrusions, within the body and gate, and of different forms or combinations of forms,

reducing the bore between said gate and a rigid and an ularly directed or integral hand hold or andle 18, the same bein mounted to swing upon a vertical axis, an

upon a hinge pm or pintle 19, which is mounted in top and bottom lugs or ears20 upon the gate or door or closure B, and ranging outwardly and laterally therefrom, so that said T-head may be swung inwardly of and enga e with locking heads or keepers 21 ranging orwardly from one of the end extensions a of the body A. The T-head moves into position behind the keepers 21 through an opening in the member A between the keepers and openings 51 in the member A at the level of said keepers. These openings 50, 51 extend to the outer face of the member A and the handle 18 projects from the member B in a direction away from the pivot 16, or outwardly from a. plane passing through the keepers and the pivot 19. This construction entails that the unlatching pull exerted on the handle 18 will have maximum opening effect on the member B as soon as the T head has operated a sufficient distance to disengage the keepers. Inte ral with or rigidlyV secured to said T-head 1 and handle 18 is a lug or ear 22 rangin oppositely to the handle 18, and dis ose normally so as to .be slightly spaced rom th'e forward face 23 of the gate, a compression spring 24 being disposed between such bo and gate, and yieldingly permitting the andle member 18 to be swung in a direction to retract or disengage the T-head from the lugs or keepers 21. These kee ers or lfbkingheads 21 range both outward y and yertically, as clearly shown in Figure 14. This same movement of the handle member 18 after disengagement with the T-head 17, if continued in direction after such disengagement, and after the compression spring 24 have been com ressed and the lug 22 brought back against t e gate or adjacent thereto, will serve to move the gate in an opening direction, such movement being centered at the hinge means b, and utilizing the anti-friction means E or any of the 'modified forms F, G, and H, or others, or in lieu thereof, utilizing the modified hinge means K, will serve to cause the gate not only to move in an opening direction but to move in a vertical direction, disengaging the outer or free end portion of the gate. Such engagement, when the gate is closed, is effected through c0engaging heads or lugs 25 and 26, respectively, upon the gate and body, and most clearly lllustrated in Fi ure 3, and which are included in the interloc ing means D and which range upwardly and outwardly upon the body and downwardly and inwardly upon the gate, suflicient clearance being provided as between the same to accommodate closing and opening movements of the gate, and yet permit such lugs or heads to come into effective engagement when the gate is closed. It will be under- 'stood thatthis co-engagement of these lugs and heads serves to impart tothe body a portion of the load directly imposed upon the gate, the remaining portion being imposed upon the gate at the hinge means b. The locking device c, which really is but a master member for locking means as an entirety, includes o'r may comprise a swinging latch member 27 mounted upon a bolt 28 threaded into the forward portion of the gate B, such latch member having a fingerieee 29 for its convenient manipulation, sai latch member being adapted to be raised from the pendent position shown in dotted lines in Figure 1, and swing around into position to project at its outer end between the lug 22 and the front face 23 of the gate, and to be retained in such latter position by resting upon one of the springs 24. Obviously this disposition of the latch member last mentioned will prevent approach of the lug 22 toward the said forward face of the ate, and therefore prevent disen agement o the lhead 17 from the locking ugs or heads 21, in other words, serving as a master locking member to retain and maintain the ate in locked condition, which condition is urther effectively maintained by the inter-enga ement of the lugs or heads 25 and 26 which can not be disengaged until the latch means are operated to permit the door to swi and rise. Thus, with the locking member 2 1n operative position as shown 1n Fi ure 1,

the latch means C must remain in e ective position and condition, the lugs 25 and 26 must remain inter-engaged, and the door is Vim positively locked against movement in an opening direction, oi' against rising.

The movement of the gate in a vertical direction, to rise when opened and to descend when closed, is effected in either case through the cooperation of the parts of the anti-friction means E, which are clearly shown in Figures 1, 2 and 13 as comprising cooperating members y and 31, respectively, mounted upon or associated. or connected with the gate and body, adjacent the hinge means or pivotal connection b. It is obvious that said members may be substituted each for the other, and this reversal or substitution of parts and features'may obviously be indul ,ed in in racticing the invention by use o the modified structures shown in Figures 4 to 7 inclusive. In the specific showing of the drawings, the means E comprise a roller, as the member 30, rotatably mounted upon a stub shaft 30a set into a recess produced through the vertical face of a lug 32 upon the forward face of the gate, such roller being disposed in position to travel over the member 31 which may comprise a xed cam body 31a upon the body and curved to a generating center which constitutes the axis of the hinge means b. This cam body 31 has a relatively abruptly upwardly inclined face 31b which is engaged by the roller 30 to produce upward opening movement -of the gate to a partially open position and a less abruptly downwardly inclined face 31c which permits descending movement of the gate to full open position. In other words, as the gate is moved in an opening direction, the roller travels up over the face 31h, then across the horizontal or dwell portion 31d at the top of the cam body 31", and then travels downwardly over the face 31. When the gate is either open or closed the lower face of the knuckle 15 rests down upon the top face of the lower knuckle v16; the clearance between the top of such knuckle 15fand the bottom of the top knuckle 16 permitting the vertical play of the gate.

The lug 32 is chambered out for the accommodation of the roller 30,'as more clearly shown in Figure 4. The gate is pinned fast to the pintle 33 of the hinge means b, and said pintle is obviously free to rise and fall in the upper and lower knuckles 16, such pin being clearly shown in Figure 4 at 34. In Figure 5 a modified form of the means E is shown at F, the same comprising two members, 35 and 36, the form of which includes a rotating angular head or block, mounted upon a similar short or stub shaft or pin 30a similarly received in the door or a chambered lug 32 thereon; and this rotating angular block cooperates with an angular cam body 36 mounted upon the body A and having a horizontal top surface portion 36 and substantially vertical side faces 36b and 36C. When the door is moved in an opening direction this block 35 rotates and steps up onto the surface portion 36a, and as opening movement of the gate or door is continued it rotates and steps olf therefrom and down over or beyond the veitical face 36, thus permitting the gate t0 rise and then to lower after it has been opened. The reverse of these movements takes place in the moving of the gate in a closing direction.

In Figure 6 is shown a still further modified form of construction, the parts and their cooperation being all the same as lastdescri ed, save and except that in substitution for the angular block 35 I provide a roller 30e similar to the roller 30 but cut away at its periphery in a number of zones of the same dimensions, as at 37, thus forming peripheral recesses which are receivedby the corner portions of the cam body 36, which portions or edges are preferably rounder off as at 38, thus permitting of a curved surface engagement between the roller 30e and such cam body 36. This reduces `friction and wear, and where four of such recesses 37 are provided, one of saine in any given adjustment will always engage with the rounded portions 38. Such roller 30e may obviously be adjusted so as to bring a different recessed portion 37 into play after long continued wear or service.

. In the form of construction shown in Figure 7 I utilize two engaging rotating blocks 39 and 40, the former of which is mounted to rotate upon a similar short shaft 30a received within the recessed lug 32 on the gate B, and the latter of |which is mounted, similarly rotating upon a short shaft 41 mounted upon the body A adjacent vrthe hinge means b, and in the movement of the gate from closed to open position the block 39, which is preferably slightly rounded or curved at its faces, rides up over the block 40 by engaging the same and rotating it, as theA block 39 rotates, and ultimately the block 39 and block 40 in a coit'inuatdollof their turning movement bring the block 39 to a position at the opposite side of the short shaft 41, thus permitting the gate to fall. A reverse movement of the gate will cause a reverse operation of these roller blocks. As any one of the faces of the block 39 always engages with one face of the block 40, obviously either block 39 or 4() can be adjusted to bring a fresh face or fresh faces into'coengagement.

All of these anti-friction means E and the substitute forms materially reduce the wear and friction incident to the opening and closing and raising and lowering of the door, and prevent de-forination of the metal orvinaterial of the parts and the wear of same which if more than slight will prevent proper operation of the gate, and its proper opening and closing and raising and lowering, and the proper co-engagement of the -lugs or heads 25 and 26.

In Figure 8 is shown a modified form of the hinge means b for producing rise and fall of the gate B, such means K producing such results in an anti-friction manner, through the agency of a helical groove 42 in the pintle 81, a ball 43 protruding into said groove and being chambered in part in a recess 44 in the body A or threaded nipple 45 set into such recess. As the gate is moved in an opening direction the ball 43 will act in the portion 42al of the groove 42 of sharp pitch, causing the pintle 31 andrdoor fixed thereto to rise.

It is obvious that the cooperating parts and features of all the forms of construction shown in Figures 4 to 8 inclusive may be reversed or substituted each for the other, without the necessity of any invention being employed to that end, and to produce substantially the same results in substantially the same manner, within true equivalence.

In Figure 9 the means M is shown as an arched inward enlargement 46 within the body A, and sich means M it will be understood is provided, as are the means N, O, P, not only within a portion of the objectreceiving bore in an elevator that is bounded by a body A but likewise the part of such bore bounded by the gate B. Such means may be provided at equidistant points or in zones equally relatively spaced, and afford means for closely engaging the pipe, tubing or other object upon the closing of the gate. Likewise, suc formations may be machined olf or machined back to permit the elevator to receive and accommodate objects of larger dimensions or diameters. Furthermore, inasmuch as such formations do not extend entirely around the confines of the bore, below the preferably'continuous inward intrusions L, mud and detritis are free to drain downwardly from within the elevator and itsv bore and keep such bore clear.

The means N comprises an inwardly pro- 'ecting stud or studs 47, which may be staggered in a'-horizontal zone of the elevator. The means O may comprise a plurality of spaced elongated vertically disposed intrusions or projections or bosses 48.

The means P may comprise both thevertical bosses or projections 48 and the studs 47, the studs being arranged in alternation with the projections 48, and preferably in a series.

The gate is held in open position when the roller 30 or substitute part is moved beyond the cam body 36 or the like. When such part 30 or the like is superimposed upon the cam body or the like, a gentle urge in the proper direction will move the gate into eit er open or closed position.

In operation it will be understood that the elevator is applied to the pipe, tubing or other object by bringing such body into the portion of the bore within the body A, whereupon the gate is closed over it, completing the form of the bore and embracing the o ject, and a collar or coupling or union of the joints or sections of casing or tubing or lengths of sucker rod and the like may rest upon the top surface of the elevator and the gate, whereupon the gate may be suspended and operated in the usual or any preferred manner. The latch means C ma readily be operated either to engage the head 17 with the locking heads 21 or to disengage it therefrom, by munipulating the handle member 18, the spring 24 serving to keep the said parts in co-engagement, yieldingly, which co-engagement may be positively maintained by bringing the lock member 27 into position between the lug 22 and the forward face of the gate, whereupon the head of the bolt 28 or nut thereon may be tightened down to maintain such position, thus locking the te against any possible opening, both by t e T-head and lugs 21 and the inter-engaging lugs or heads 25 and 26. The T-head automatically engages with the lugs 21, rotating into position as the gate closes and falls. The descending action of the gate in its movement in a closing direction permits said latter heads to be interengaged, for this positive inter-lookin relation, and the ascending movement o? the gate when operated in an opening direction effectively produces disengagement of these heads 25 and 26. These ascending and descending movements are effectively and without material wear produced throu h the agency of the anti-friction means E, G or H, or the anti-friction substitute hinge means K. These inter-engagements are produced with precision and without interference.

The action of the various inward rojections or intrusions, L, M, N, O and will be readily understood from the foregoing statements, which likewise will more fully inform as to the action of theother parts and features just touched upon.

It is obvious that various changes and modifications may be made in practicing the invention, in departure from the foregoing description and statement, and the disclosure of the accompanying drawings, in adapting the improvements to varying conditions of use and service, without departing from the true spirit of the invention.

Having thus disclosed m invention, I claim and desire to secure by tters Patent:

1. A device of the general4 character disclosed, comprising two members adapted to embrace an object, and latch means for holding said members in embracing relation and comprising a swinging T-head on 011e of said members and spaced angular lugs on Maaate l the other of said members for co-engagement with said T-head to o pose relative movement of said ymembers 1n an opening direction, there being openings in the second mentioned member at the level of the lugs extending to the outer face of the second mentioned member to permit of the movement of the T-head to and from position behind the lugs; saidlatch means having a handle rigidly. connected with said T-head.

2. A device ,of the generalcharacter disclosed, comprising' two members adapted to embrace an object,` and latch means for hold` ing said members in embracing relation and comprising a'swinging T-head on one of said members and spaced angularl lugs on the other of said members for co-engagement with said T-head to oppose relative movement of said members 1n an opening direc- 4 mentioned member at .the level of the lugs i tion, .there being openings in the second extending to the outer face., of the second mentioned member to permit of the movement of the T-head to and from position behind the lugs; means being provided tending to maintain said T-head and lugsincofengagement; said latch means having a handle rigidly connected with said T-head.

3. A device of the general character disclosed, comprising two members adapted tol 'embrace an object, and latch means for holding said members in embracing relation and .comprising a swinging T-head, angular lugs vonthe other of said members for coenga ey -ment with said T-head to o pose relative v nlng 1 direction, there being openings in t e` sec-` movement of said members in'anio 4.` A device or'jthe general character dis-` closed, comprisingr two members adapted to embrace `an object, and latch means for holding said members in embracing relation andy comprising a swinging T-head on one end of one of said members and spaced angularlugs on the other of'said members for coengagem'ent with said T-head to oppose relative movement of said members in an opening direction; said T-head 'being provided with a handle member, and the-relative arrangement andassociation of parts and feaytures being such that a movement of said handle member toward the opposite end of thev rst mentioned member vto' disengage said-T-head from said lugs will if continued' tend to relatively separate said membersor open said device,

5. A device of the general character disclosed, comprising two members adapted to embrace an object, and latch means for holding said members in embracing relation and comprising a swinging T-head on one end of one of said members and spaced angular lugs on the other of said members for co-engagement with said T-head to oppose relative movement of said members in an opening direction; said T-head being provided with a handle member, and the relative arrangement and association of parts and features being such that a movement of said handle member toward the opposite end of theirst mentioned member to disengage said T-head from said lugs will if continued tend to relatively separate said members or open said device; means being "provided tending to maintain said T-head and lugs in co-en agement.'y

6)` A evice of-the general character disclosed, comprising two members adapted to embrace an object, and latch means for holding said members in embracing relation and comprisinga swinging T-head on one of said members and spaced angular lugs on the other of said members for co-engagement Awith said `T-head to oppose relative movementof said members in an opening directively. locking said T-head and lugs in coengagement, said locking means being selff retainin in said position.

7. A evice of the general character disclosed, comprising two members adapted to embrace an object, and latch means for holding said members in embracing relation and comprising a swinging T-head on one of said members and spaced an lar lugs on the other of said members or co-engagement tion.; rmeans on `the first mentioned member l'manually operable into a position for posi-y ite with said T-head to` oppose relative movement of said members 1n an opening direction; means on the rst mentioned member manually operable into a position tending to maintain said T-head and lugs in co-engagement; said last named means cooperat- 1ng with said first mentioned means tending taining in said position.

1 8. A device ofthe general character disclosed, comprising two members adapted to embrace an object, and latch means for holding said members in embracing relation and vcomprising a swinging T-head on one of said members and spaced angular lugs on the other of said members for co-engagement with said T-head to oppose relative-movement of said members in an opening direction; means being provided tending to maintain said T-head and lugs in co-engagement; said last named means cooperating with .sa irl 115 to oppose relative movement of said T-head and lugs, said locking means being self-refirst mentioned means tending to oppose relative movement of said T-head and flugs, and including a swinging lock member.`

9. In a device of the general character disclosed, two members adapted to embrace an object, releasable latch means for maintaining said members in closed relation, and means manually operable into a osit-ion for positively maintaining said latc means in latching condition, said last mentioned means being self-retaining in said position.

10. In a device of the general character disclosed, two members adapted to embrace an object, releasable latch means for maintaining said members in closed relation, means for positively maintaining said latch means in latching condition; sald members having inter-engaging parts likewise maintaining said members in closed relation and rendered effective to that end by said other means, and anti-friction means including);

`rotatably mounted member effective as tween said first mentioned members in movement of one of said first mentioned members in an opening direction and whereby said first mentioned member is raised.

11. In a device of the general character disclosed, two members adapted to embrace an object, releasable latch means for maintaining said members 'in closed relation, means for positively maintaining said latch means in latching condition; said members having inter-engaging parts likewise maintaining said members in closed relation and rendered effective to that end by said other means; means being provided for producing an opening or relative separation of said members permitting disengagement of said members where co-engaged, and anti-friction means including a rotatably mounted member effective as between said first mentioned members in movement of one of said first mentioned members in an opening direction and whereby said first mentioned member is raised.

12. In a device of the general character disclosed, two members adapted to embrace an object, said members being hingedly associated, and anti-friction means including a rotatabl mounted member effective as between sai( first mentioned members in movement of one of said first mentioned members in an' opening direction and whereby said last named member is raised.

13. In a device of the general character disclosed, two members adapted to embrace an object, said members being hingedlyT associated, and anti-friction means including 'gv a rotatabl mounted member effective as between sai( first mentioned members in movement of one of said first mentioned members in a closing direction and whereby said last named member is lowered.

14. In a device of the general character disclosed, two members adapted to embrace l' an object and hingedly associated, and antifrietion means including a rotatably mounted member effective to cause raising of one of said first mentioned members in movement in one direction and lowering of said member in moving in another direction.

15. In a device of the general character disclosed, two members hingedly connected and adapted to embrace an object, and antifriction means effective between said members to produce change of position of one of said members in a vertical direction durin relative movement of said members; said anti-friction means including a rotating part associated, with one of said members. f

16. In a device of the general character disclosed, two members hingedly connected and adapted to embrace an object, and antiriction means effective between said members to produce change of position of one of said members in a vertical direction during relative movement of said members; said,

anti-friction means including .a pintle for said hinge connection, said pintle having a helical groove, and a projection from the other member entering said groove.

17. In a device of the general character disclosed, two hingedly connected members adapted to embrace an ob'ect in a bore between the same, and anti-friction means ineludin a rotatabl mounted member acting to bot raise am lower one of said first mentioned members in a continued movement in a given direction.

18. In a device of the general character disclosed, two members adapted to embrace an object, releasable latch means for maintainin said members in closed relation, and including a T-head movably associated with one of said members and a keeper on one said member engageable by the T-head, there being an opening at the level of the keeper extending to the outer face of the other member to ermit of movement of the T- head to and from a position behind the keeper, and means for maintaining said latch means in latchinv condition.

19. In a device of tie general character disclosed, two members adapted to embrace an object, releasable latch means for maintaining said members in closed relation, and including a T-head movably associated with one of said members and a keeper on one said member engageable b the T-head, there 'being an opening at the evel of the keeper extending to the outer face of the other member to permit of movement of the T- head to and from a position behind the keeper, and means for maintaining said latch means in latching condition; said latch means preventing said members from having relative vertical pla 20. In a device o? the general character disclosed, two members adapted to embrace an object, means including a rotatablyky mounted member' and causing relative vertical play of said members when relatively moved to open or close same, and releasable means for maintaining said rst mentioned members in closed relation and preventing such relative vertical play.

21. In a device of the general character igglisclosed, two members adapted to embrace an object, means including a rotatably mounted member and causing relative play of said members when relatively moved to open or close same, and releasable means for maintaining said first mentioned members in closed relation and preventing such relative vertical play; means being provided :for maintaining said latch means in opera# tive condition.

22. In a device of the general character i described, two' members pivotally connected and adapted to embrace an object, releasable latch meanf for maintaining said members in closed relation, said-#latch means having a handle memberprojecting-in a direction away from the pivot whereby the latch means may be operatedand whereby in movement of the handle in one direction one of said members may be unlatched and opened and in the opposite direction may be closed and latched, and anti-friction 7 means including a rotatably mounted member effective as between said rst mentioned members in movement'of one of kSaid first mentioned members in an opening direction and whereby said one first mentioned member is raised.

23. In a device of the general character disclosed, two members adapted to embrace" an object, said members being hingedly connected, 'and means whereby one of said members when moved in a given direction will first rise and then fall; said means `'being formed to sustain said member in an intermediate raised position, from which position it may move and descend when swung in either direction.l l

24. An elevator comprising hingedly connected sections forming between them an opening to receive a casing, the sections having portions that interlock on relative vertical shiftin of the sections, an inclined face on one en of one of the hinge members, a

roller on the adjacent end of another of the hinge members to ride on the inclined faceV and anti-friction means including arotatably mounted member eifective as between the sections in movement of one of said sections in an opening direction and whereby said last mentioned section is raised.

25. An elevator comprising hingedly connected sections forming between them an opening to receive a casing, the sections having portions that interlock on relative vertical shifting ofthe' sections, an inclined ace on one en d `of one of the hinge members,

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