US2158232A

US2158232A - Drilling hook

Info

Publication number: US2158232A
Application number: US178240A
Authority: US
Inventors: Herbert E Grau; Richard K Hertel
Original assignee: Byron Jackson Co
Current assignee: Byron Jackson Co
Priority date: 1937-12-06
Filing date: 1937-12-06
Publication date: 1939-05-16
Anticipated expiration: 1956-05-16

Description

May 16, 1939- H. E. GRAU ET AL DR ILLING HOOK Filed Dec. 6, 1937 3 Sheets-Sheet 2 y 16, 1939- H. E. GRAU ET AL 2,158,232

DRILLING HOOK Filed Dec. 6, 1937 3 Sheets-Sheet 3 Snug-Wm Md Wily/M Patented May 16, 19 39 UNITED STATES PATENT OFFICE DRILLING HOOK Herbert s. cm and Richard K. Hertel. vmon.

assignors to Byron Jackson 00.. Huntwells. More specifically, the invention relates to the general type of hook Calm, ington Park,

GaliL, a corporatlon of Delaware Application December 6, 1937, Serial No. 178,240 19 Claims. (61. 294-82) This invention relates to hoist line hooks, such as are used particularly in the drilling 01 oil disclosed in the patent 29, 1931. and involves various modifications and improvements of the hook construction disclosed in that patent.

A broad object oi the a drilling hook having invention is to provide a hook portion and a hook-supporting portion pivotally connected thereto for free rotation about a vertical axis and also having a universal connection for permitting free swiveling oi the hook relative to the hook-support in any horizontal direction.

and means for locking the swivel connection Various other objects,

together with the speciflc features and advantages of the invention, will become apparent from the following description of a preferred form to the drawings.

In the drawings:

thereof, with reference Fig. l is a side elevation of a drilling hook in accordance with the invention.

Fig. 2 is a front elevation of the drilling hook.

Fig. 3 is a vertical section, taken approximately in the plane III-III of Fig. 2.

Fig. 3a is an enlarged the same plane as Fig. 3,

detail section taken in to better bring out certain details of construction.

Fig. 4 is a cross section, taken in the plane IV--IV of Fig. 3.

Fig. 5 is a detail vertical section taken approximately in the plane V-V Fig. 6 is a detail cross section,

Fig. 3a.

in the plane VI-VI of of Fig. 1.

approximately Fig. 7 is a detail vertical section similar to Fig. 3a, but taken in the plane VII-VII of Fig. 6.

Referring to Fig. l oi comprises as its the form of an inverted U the drawings, our hook essential elements a bail i in -shaped member adapted to be detachably connected to a traveling block or other housing device, not shown, and having its two ends connected to the upper end of a housing 4. The housing 4 contains a spring mechanism for supporting a hook body 33, hav- 8 ing at its lower end a bill It which constitutes the hook proper.

Referring now to Figs. 1 and 3, the lower ends 01' the ball I are provided with eyes 2 through which extend pins 3 for securing the bail to the housing 4, the latter having a pair 01' oppositely disposed laterally extending slotted ears I (Fig. 2) through which the pins 3 extend.

The housing 4 is approximately cylindrical in shape, except for the protruding ears 8, and is. open at both its upper and lower ends. The Upper end of the housing l is closed with a removable cover 6 secured in position by nut I (Fig. 2).

Positioned within, and extending up through the housing 4 is a hook shank I! (Fig. 3), which hook shank functions to support the hook body 33 from the housing 4. The connection of the lower end of the shank ii to the body 33 will be described in detail later. Sumce it to say that the lower end of the shank l5 passes through an aperture defined by an annular inwardly extending flange ll on the lower end of the housing 4, which flange It makes a close sliding flt with the hook shank it for free vertical movement 0! the shank ii downwardly with respect to the housing I. Upward movement of the shank it, with respect to the housing I from the position shown in Fig. 3, is limited by an outwardly extending annular flange 21 on the shank 15 which normally bears against the underside of the flange II.

The shank i5 is resiliently supported against downward movement with respect to the housing 4 by a pair of helical springs l8 and I9, respectively, which are compressed between a nut ill on the upper end of shank l5 and the lower end of the housing I. Thus the lower end of the inner spring i8 rests against the upper face I! of the flange l4 and the lower end of the outer spring I9 is supported on the upper face of an inwardly extending annular flange on the housing 4, which flange 20 is of larger internal diameter and is positioned slightly above the flange ll.

The nut I0 is screwed onto the upper end of the shank l5, as previously indicated, and the normal compression of the spring members It and I9 may be adjusted by turning the nut It on shank it. It is necessary, however, to ilrmly lock 55 the nut against rotation after it has once been set. There are several ways in which the nut can be locked: the particular, effective method is shown in Figs. 3 and 4, in which the extreme upper end of the shank l5, above the threaded portion thereof, is made polygonal in shape, thereby providing a plurality of flat surfaces 32, one of which is adapted to bear against a flat side of a wedge-shaped key 3|, which key is received in a slot formed in the upper end of a nut ll. One end of the slot 23 is closed by a web 23 (Fig. 4) having a hole therein through which extends a bolt 34. The wedge-key 3| is provided with a threaded bore 23a to receive the threads of bolt 24. With the construction described, the nut It may be locked in any one of a plurality of positions by turning it so that one of the flat sides 22 of the polygonal end is juxtaposed to the slot 33, inserting the wedge-key 2i and looking it in place with the bolt 24. As shown in the drawings, the polygonal upper end of the shank I5 is triangular, but if a finer adjustment is desired this nut may be made rectangular, hexangular or octangular.

When the load on the hook exceeds a predetermined value, the springs l8 and I3 compress to permit downward movement of the shank ll out of the housing 4. It is desirable that during such separating movement a seal against dirt and other foreign matter be maintained about the shank l5 and between the lower end of the housing 4 and the upper end of the hook body 33. To this end we have provided on the lower end of the housing 4 a sleeve l3 which is adapted to ride vertically therealong in response to movement of the shank l5 and has a packing ring l3a which slides over a smooth cylindrical surface portion of the housing 4, thereby maintaining a seal with the housing regardless of vertical movement of the sleeve therealong. At its lower end the sleeve I3 is provided with a re-entrant annular wall portion 33 which in turn has an inwardly extending flange 31 thereon, the upper face of which constitutes a shoulder bearing against the underside of the edge of the flange 31 on the shank l5 so that the sleeve I3 is constrained to follow the shank downwardly when the latter moves with respect to the housing 4. When the shank l5 moves upwardly, with respect to the housing 4, the sleeve I3 is forced to follow the shank by contact with the upper end of the hook body 33, which moves vertically with the shank it. Thus there is defined between the re-entrant wall 65 of the sleeve '3 and a downwardly depending skirt l3b on the sleeve, an annular channel in which is slidably mounted for vertical movement a ring 53, which ring is provided with a packing ring 33 sealing with the inner surface of the skirt I317.

The lower end of the ring 53 is provided with a concave spherical surface 32 adapted to bear against a corresponding convex spherical surface on the upper end of the hook body 33. The ring 53 is maintained in engagement with the juxtaposed spherical surface of the hook body 33 by a plurality of helical springs which are compressed between a seat II in the ring 33 and the upper end of the channel in the skirt ill), in which the ring 59 is positioned. Each of the springs Bil is partially enclosed in a cylindrical housing extending upwardly from the upper surface of ring 53, as clearly shown in Figs. 3a, 8 and '7.

In accordance with the invention, the hook body 33 is connected to the shank II for unlimited rotation about the vertical axis of the shank II and also for swivel movement in any lateral direction with respect to the axis of shank It. To this end shank I3 is threaded at its lower end, within the hook body 33, to receive a nut 33 which is secured against accidental rotation of the shank II in the same manner as is the nut ll (previously described) on the upper end of the shank. This nut 33 is provided with a concave spherical surface 32 having a center of curvature the same as the center of curvature of the spherical surface on the upper end of the hook body which bears against the spherical surface 62 on the ring 33. The spherical surface 32 on the, upper end of nut 33 bears against a corresponding convex spherical surface on a lower bearing race of an antifriction bearing (shown in the drawings as a ball bearing), the upper race 33 of which bearing rests in an annular seat 38 formed in the body member 33. The upper race 38, seated in the hook body 33, is rotatably supported on the lower race member 43, which rests against the nut 33 on the shank it. The body member 33 is thereby rotatably supported by the bearing on the shank ii for unlimited rotation about the axis of the hank. It is also oscillatable in any vertical plane passing through the axis of the shank I! by virtue'of the sliding contact between the spherical surface on the nut 30 and the lower bearing race 40. Such oscillatory movement is possible without permitting the entry of dirt into the interior of the body member 33 by virtue of the seal between the spherical surfaces on the ring 33 and the upper end of the body 33, respectively, which spherical surfaces have the same center as the spherical surface 32 on nut 3|). By virtue of the fact that the ring 63 is constantly pressed into intimate contact with the upper end of the hook body 33 by the spring 60, sufllcient resistance is introduced to sliding movement between these surfaces to prevent the body 33 from swiveling too freely about the shank ll.

It is also desirable that the frictional contact between ring 59 and the upper end of the body 33 be utilized to restrain, to a certain extent, rotation of the body 33 with respect to the housing 4. To this end it is necessary to restrain the ring 33 against rotation with respect to sleeve l3 and to restrain the sleeve I3 against rotation with respect to the housing 4. To this end the ring 39 is provided with an inwardly extending integral key 59a (Figs. 3a. and 6) which extends through a slot 59b provided in the sleeve l3 and into a recess 21a provided in the flange 21 of the shank lb. The key 59a is free to move vertically with respect to the sleeve l3 and the shoulder 21 but is restrained from rotation with respect thereto. Accordingly, the ring 59 is at all times constrained to rotate with the sleeve l3 and the shank ii.

To prevent any possibility of the bearing 39 leaving the seat 33 when the hook is not under load, the lower end of the sleeve i3 is shaped to define a shoulder 4l shaped to bear against the spherically curved surface on the upper end of the body 33 and also form on the sleeve l3 an upwardly facing annular shoulder 42 adapted to bear against the underside of the annular flange 31 on the shaft ll. Therefore, when the nut 33 is tightened on the shank l5 into position of proper adjustment, the clearance between the flange 31 and the shoulder 42 and between the shoulder 4| and the body 33 is reduced to such a small value as to prevent any appreciable separating movement between the bearing

races

33 and 40 or between the upper bearing race" and its seat II. V

Itis some times desirable to positively lock the hookbodyll againstrotationwithrespecttothe shankil andtothisen'd theshank lihasformed thereon, at a level within the upper portion of the body ll, an'enlarged head 28 positioned immediately below the flange 21, which head is provided with a series of vertical slots 43 adapted to receive clocking member mounted in the body 22. Any desired number of slots 48 may be employed, but in the particular embodiment shown, four are provided. The locking member in the body 23 for cooperating with the slots It. comprises a lever ll mounted'on a horizontal pivot pin II which, in turn, is rotatably mounted in a cover plate or member II secured to the body IS and closing an opening leading into the hollow interior upper portion of the body in which the swivel supporting structure previously described is positioned. As shown in Fig. 5, the cover plate II is secured in place by bolts 81.

One end of the pin ll (the rear end with reference to Fig. 3) extends through the cover plate 0 and has a handle 01 whereby it may be rotated. 'The upper end of the lever 44 extends inwardly and normally rests in one of the vertical slots ll in the head 28 when the lever is in locked position. The lever is rotated through a small are into locked position in which its upper and extends into one of the slots 43 or out of locked position, clear of the head II. by means of the handle I. In order to releasably retain the lever 44 in either locked or unlocked position.

, it is provided with a retractable bolt 49 slidably mounted in a longitudinal recess within the lever M and projecting therefrom at the upper end. The bolt 48 is constantly urged upwardly by a hollow compression spring 52 positioned in the recess in the lever ll therebelow. The upper end of the bolt It is beveled on two sides to provide two faces 52 and M, respectively, and the cover plate 46 is provided with a boss Bl on its inner surface adapted to be contacted by the bolt 09, and having a surface, II adapted to be engaged by the surface 83 on the bolt when the lever is in looking position, and having a surface lit adapted to be engaged by the bolt surface 54 when the lever is in unlocked position clear of the head 28. During movement of the lever 44 from either position to the other, the bolt 0 is first depressed to compress the spring 52, and is then forced outwardly again by the spring so that substantial force is required to move the lever from either extreme position to the other.

The cover plate 46 not only serves as a convenient support for the locking mechanism described, but also gives access to the interior of the body 33 and facilitates adjustment or removal of the nut SI and the bearing, including the races II and 40.

As previously indicated, the hook body 12 is provided at its lower end with a bill Iii which extends forwardly-and upwardly and constitutes the hook proper. When the hook is engaged with the bill, it is desirable that the hook opening be closed to prevent accidental escape of the bolt. To this end the bill I! is slotted at its extremity, as indicated at H, to receive a closure arm 12 which is pivotally connected to the bill by a pivot pin 13. The slot H in the bill is extended inwardly substantially beyond the lowermost portion of the bail-supporting surface of the bill to receive an inwardly extending finger 14 which is formed integrally with the closure arm 12 and whenthelatterisinclosedposition the upper surface oi the finger ll is substantially flush with the bail-supporting surface of the bill.

The closure arm I! is provided with an aperture adjacent its upper end. which aperture is adaptedtoreoeive,whenthearmisin closed position, a forwardly extending lug formed on the body 33. The upper wall of the aperture in arm I! and the upper surface of the lug II are preferably curved about the pivot 18 as a center, so that the arm I2 is free to swing from closed to open position and have relatively small clearance with the upper surface of the lug II when in closed position. By providing relatively small clearance between the juxtaposed surfaces of the lug Ill and the arm I! when the bill II is loaded suiiiciently to cause it to yield slightly. the juxtaposed surfaces of the arm 12 and the lug II will be brought into contact with each other, thereby transferring part of the load to the. arm 12 and the lug Ill and greatly increasing the carrying capacity of the hook.

Should the closure arm 12 not be in fully closed position at the time the load is applied to the hook, then the ball or other wedge-supporting member will contact the finger It on the closure arm, forcing the finger down until its upper surface is flush with the adjacent load carrying surfaces of the bail and positively forcing the closure arm 12 into closed position.

It is very desirable, of course, that when the closure arm has been once moved into closed position that it be positively locked against accidental release while at the same time being releasable by the operator. To hold the arm 12 in closed position, we provide a latch means, including a reciprocable bolt 82, mounted in the arm 12 for longitudinal motion and adapted to engage a recess 23 formed in the underside of the lug 80. The bolt 82 is supported vertically by a horizontal pivot pin .4 which is mounted in a latch carrier 88 which comprises a slotted frame slidably supported for longitudinal movement in the arm 12 and normally urged upwardly by a helical compression spring 81 positioned therebelow.

The upper end of the bolt 82 is beveled downwardly and inwardly to provide an angular end face 88 and the front underface of the lug an is likewise beveled downwardly and inwardly to provide an angled latch contacting face 90 so that when the arm 12 is moved from the open position toward closed position, surfaces 89 and 90 will cooperate to press the bolt 82 downwardly. allowing the arm 12 to move into fully closed position in which the aperture therein receives the lug Ill, in which position the spring 81 presses the latch carrier and the bolt 82 upwardly, causing the bolt 82 to move into the recess 83 and thereby lock the arm 12 in closed position.

Obviously, before the arm 12 can be opened, the bolt 82 must be retracted downwardly a sufficient distance to clear the recess 82 and such downward movement of necessity moves the latch carrier 85 downwardly against the force exerted by spring 81. In view of the fact that the axis of movement of the bolt 82 and the spring 81 is parallel to the vertical axis of the hook body, a sharp blow applied to the body 33 in the direction of its vertical axis might cause the bolt 82 to compress the spring 81 and allow the arm 12 to open accidentally. To prevent possibility of such an occurrence we provide a secondary latch comprising a T-shaped member 92, which, like the bolt 82, is pivotally mounted on the pin 84, the 1g .to the axis of spring 91.

member 99 being positioned in a recess in the front face of bolt 92. The member 99 has a downwardly extending leg 94, the lowerend of which normally rests upon a ledge 99 on the arm 12 and thereby prevents downward movement of pin 94, and the bolt 92, with respect to arm 12. The member 93 has an upwardly extending arm 91 which bears against one end of a horizontally positioned helical compression spring 99, the opposite end of which spring is received in a recess 99 formed in the latch carrier 99. This spring constantly urges the member 99 to rotate about the pin 94 in a counter-clockwise direction (with reference to Fig. 3), thereby maintaining the lower end of the arm 94 above the ledge 95 to prevent downward movement of the bolt 92.

The member 93 is provided with a forwardly extending handle or finger I99 for manual actuation, which finger is positioned within a handle 92 on the latch carrier 95. Pressing the finger I99 on the member 93 downwardly disengages the lower end of the leg 94 from the ledge 95 to permit downward movement of the latch carrier and the bolt, and the latch carrier and bolt may then be moved downwardly by pressing downwardly on the handle 92. The upper upwardly extending arm 91 of the member 93 normally bears against the rear wall of the recess in bolt 92, in which the member 99 is partially positioned, so as to limit rotation of member 93 in counterclockwise direction in response to force exerted by the spring 99. The rear wall of the recess also acts as a stop to be contacted by the leg 94, thereby limiting rotation of the member 93 in a clockwise direction in response to movement of the downward force supplied for the finger I99.

It will be observed from Fig. 3 that the bolt 92 is not only urged into upward position into the recess 99 by spring 91, but is positively prevented from moving downwardly by the engagement of the leg 94 on member 93 with the ledge 99 on the arm 12 and the member 93 is maintained in this position by the spring 99 which is positioned with its axis of movement substantially at right angles Therefore should the hook receive a blow in a vertical direction capable of displacing the bolt 92 against the resilient force exerted thereon by the spring 91, the bolt would still be prevented from such movement by engagement of the leg 94 with the ledge 99 and since the latter engagement is maintained by the spring 99 positioned at substantially right angles to the spring 91, the blow that might be effective to compress spring 91 would not be effective to compress the spring 99. Likewise, should the hook receive a lateral blow in such direction as to compress the spring 99 and disengage the leg 94 from ledge 99, the bolt would not be opened because such a blow would not be eifective to compress the spring 91. The bolt 92 is therefore positively prevented from opening accidentally in response to either a vertical or a horizontally applied blow, and in actual service it has been found impossible to open the bolt 92 in response to a blow applied to the hook in any direction.

However, when it is desired to open arm 12, opening movement is readily effected by first depressing the finger I99 from the member 99 to disengage the leg 94 from the ledge 95 and then move the latch carrier 95, pivot pin 94 and the bolt 92 downwardly either by additional pressure applied to the finger I99 or by downward pressure applied to the handle 92 on the latch carrier.

By virtue of the fact that the finger I99 is positioned back of and slightly below the top of the handle 92, the latter constitutes a guard for the finger I99.

The construction of the latching mechanism described is such that whereas it is necessary to manually depress the finger I99 to release the bolt 92 and permit opening movement of the arm 12, the bolt 92 will be automatically depressed in response to closing movement of the arm 12 so that the latter may be securely locked in closed position by merely slamming it shut. Thus because of the fact that the bolt 92 is pivotally attached to the latch carrier 95 by the pivot pin 94, when the arm 12 is moved into closed position, the face 99 on bolt 92 contacts the face 99 on the lug 99, the bolt 92 is rotated about the pin 94 in a clockwise direction sufilcient to contact the upwardly extending arm 91 on the member 99 and rotate it against the pressure of spring 99, thereby carrying the leg 94 clear of the ledge 99. At the same time pressure between the

faces

99 and 99 develops a downward component of force on the bolt 92, causing it to move downwardly (following the movement of the leg 94 clear of the ledge 99) with the latch carrier 95 against the force of the spring 91. As soon as the closing movement of the arm 12 has carried the upper end of the bolt 92 past the face 99 on the lug 99, the spring 91 urges the bolt 92 upwardly into the recess 99, and as soon as the lower end of the leg 94 moves past the ledge 95 the spring 99 rotates the member 99 to bring the lower end of the leg 94 against the ledge 95, thereby locking the bolt against downward movement until the finger I99 is manually depressed.

To limit the upward movement of the latch assembly, including the pin 94 and the elements connected thereto, a roller I94 is mounted on a horizontal pin I95 secured to the arm 12, the roller I94 being so positioned that when the latch bolt 92 is in the closed and locked position shown in Fig. 3, the roller rests upon the upper surface of the housing 99 containing the spring 99, thereby limiting upward motion of the latch carrier 99 and maintaining the spring 91 under partial compression. The force exerted by the spring 91 maintains the housing 99 against the roller I94 so that the latch mechanism cannot vibrate or rattle when in the locked position.

As shown in the drawings, particularly Figs. 1 and 2, the hook body 93, in addition to having the main bill or hook 19, is provided with a pair of oppositely disposed arms I91 positioned above the bill 19 and extending at right angles thereto for the reception and support of a pair of elevator links when the hook is employed with an elevator. To retain the elevator links on the arms I91 and at the same time support the outer ends of the arms, we provide a pair of latch arms I99 resembling in some respects the arm 12 associated with the bill 19. Thus referring to Fig. 5 each arm I99 is pivotally attached at its upper end by a pin I99 with an outwardly extending ear I I9 on the body 99, the ears II9 being slotted to receive the arms I99 and permit swinging movement of the arms about the pivot pin I99. The lower end of each arm I99 is shaped to define a head II3 adapted to engage the underside of the outer end of the associated arm I91 in load carrying relation when a load is applied to the arm. Thus the juxtaposed contact faces on the shoulder H9 and the underside of the arm I91 are substantially tangential with respect to the axis of the pin I99 and there is slight spacing between the surfaces to permit free closing and opening movement of the arm I99. However, in response to a slight downward deiiection of the arm llkvhen loadis applied thereto, the contacting faces on thearm I01 andthe latch arm Ill are'brought to bear against each other and thereafter a por- 5 tion of the load onthe armfiil'l is transferred to the latch arm Nil. i

To prevent any accidental opening of the arm It and the resultant possible escape of the elevator balls from the arms I01, each oi the n arms i0! is provided with a double locking device,

which device also functions to retain each arm ill in fully opened position when desired to permit ready insertion or removal of the elevator links. I

This'iocking device comprises a lever I H which is rotatably mounted on the pin iii! and is positloned within a recess formed in the latch arm Hill. The lever lit is provided with a rearwardly extending linger ill and the lever H4 is constantly urged in counterclockwise direction (with reference to Fig. 5) by a torsion spring ill to force the finger lit against'the stop lug ,lil formed on the latch arm ill! when the latter is in closed position, and thereby limit counterclockwise movement of the lever Ill. The lever III is normally prevented from rotating out of the position shown in Fig. 5 by the finger H5 on lever ill, the end of this finger being juxtaposed to the lug ill on lever H9. with the lever I" in the position shown, opening movement of the latch arm I" is prevented by the fact that the forward face of the lug ill on lever ii! abuts against a lug I25 formed on the arm I". The abutting faces oi the lug i2! and the lug III are substantially tangential with respect to the axis of the pin I20 so that any opening movement of the latch arm I08 applies a force from lug I25 and the lug I23 in a direction substantially normal to a radius torsion and from the pin I20.

Of course a purely radial force applied to the lever 8 would not tend to move the latter in either direction but in any event rotation of the lever H9 in response to force applied thereto would be prevented either by the stop member I24 or the abutment of the ing in against the end of finger iii. In order to open the arm Hit it is,necessary to first rotate the lever ill sufficiently to cause the finger H5 to clear the lug I22 and then rotatethedever.,,l i9 upwardly and inwardly to move timing is: out of the path of the lug I25 after which the latch arm I" may be swung outwardly and upwardly away from the arm iili.

It will be observed that the lever ill extends so from its pivotal axis in a direction substantially at right angles to the direction from which the lever 9 extends from its pivotal axis. Therefore a blow applied to the lug in such a direction as would tend to open one of the levers will not tend to open the other and disengagement of the latch lug is limpossible without first releasing both levers. The latch lock described is therefore relatively immune to the eifect of jars and jolts and is substantially proof against accidental release. However, when it is desired-to release the latch am it! such release is readily eflected by first pulling out the lever ill-and then pulling up on the lever Hi. It is possible to efiect both of these operations substantially simultaneously with the fingers of one hand. However, the levers ill and ill'are both substantially completely enclosed within recesses in the arm iii! and the ear ill, respectively, so that there is little possibility oi the levers being enacted and actuated accidentally 11.? contact withsomeenternai obiect. V y

Initial opening movementorthelatcharm Ill followingtho releaseoi the levers lil-and-lll as described. carries the upper-face of the lug ill past outer face Illa of lug Ill, whereexerted by the spring Ill. The hook described operates as follows:

Assume thatthepartsareinthenormalposition shownin Figs. 1, 2 and 3, that the hook is suspended on a traveling block or other hoisting device connected to the ball I, and that it is desired tosupport a load from the hook by means of a bail engaged with the main bill or hook It of the device. The latch arm I! is first opened by hearing down on the finger IMI of the lever 93 to carry the lower end of the leg 94 clear of the ledge 86 on the latch arm I2, whereupon further downward pressure is applied either to the finger I" or the handle 92 to carry the bolt 82 downwardly against the force exerted by spring 01, whereupon the arm I! may be swung outwardly and downwardly to provide an opening for insertion of the bail to be suspended from the bill '|l. The bail is then inserted and the arm I! closed by slamming it shut. As the arm moves into closed position, the bevel face 89 on the end of bolt 82 strikes the face 90 on the body 33 causing the bolt 82 to rotate slightly in a clockwise direction about the pin it sufliciently to contact the upwardly extending arm 91 on the member 98 and rotate the latter against the iorce exerted by the spring 88 sufilcient to carry the leg 84 clear of the ledge 95, whereupon the downward component of force supplied to the bolt 82 by contact of the face I! thereon with the face 90 on the body 83, moves the bolt down to clear the body member and permit it to pass into therecessfl, the latch arm '12 at the same time moving into fully closed position, whereupon it is locked in that position by movement of the bolt 82 into the recess 8! under the force exerted by the spring 81.

Should for any reason the latch arm 32 not be fully closed, then when the hook is elevated to apply lifting force to the bail engaged thereby, the ball will bear against the finger M on the latch arm 12 and complete the final rotation of the arm 12 to carry it into fully closed position. with .the latch arm 12 in fully closed position, the latch bar 18 is positioned above the lug on the body 33 with very slight clearance between the juxtaposed surfaces. As soon as appreciable load is applied to the bill It, the .latter deflects slightly to bring the juxtaposed surfaces oi. the latch bar It and the lug 80 together, whereupon a portion of the load on the bill is transferred to the lug Oil and the supporting strength of the bill thereby increased:

If sumcient lifting force is applied through the hook structure to the load suspended. on the bill 10, the springs i8 and ID will befurther compressed. permitting the shank II and the parts connected thereto to move downwardly with respecttothehousingluntiltheloweredgeofu is leased by raising the lever lit against the force thenut ilontheupperendofshank llrests against a shoulder 0 (Fig. 3) in the housing 4. During this downward movement the sleeve I! is carried downwardly with the shank II by engagement of the flange 21 on the shank with the flange II on the sleeve. However, a seal is still maintained between the sleeve I! and the housing 4 by virtue of the packing ring "a, so that entry of dirt into the housing 4 is at all times prevented.

During the application of forces insufllcient to fully compress the springs i8 and i9, lifting force is applied from the ball I to the'upper end of the housing 4 and thence through the entire length of the housing 4 to the flanges 20 and I I which bear against the lower ends of the springs II and il. However, when the lifting force is increased beyond the strength oi the springs i8 and is, the nut it comes to rest against the shoulder 9 and all additional lifting force over that required to compress the springs i0 and i9 is applied from the bail i only through the upper portion of the housing 4 situated above the shoulder 9 therein. Therefore the lifting force applied through the portion of the housing 4 positioned below the shoulder Q is definitely limited, and this lower portion of the housing can be made relatively light and thin, it being only necessary to make the upper portion of the housing, down through and including the shoulder portion 9, sufllciently strong and heavy to withstand the maximum lifting forces to which the hook may be exposed in use.

If for any reason the load supported by the hook is not directed exactly along the axis of the hook, the body I! is free to swivel in any horizontal direction with reference to the shank it to prevent bending strains being applied to the hook. the swiveling movement taking place along the spherical contact surfaces of the bearing rest member 40 and the supporting nut 82 on the lower end of shank it. If desired, free oscillation between the body I! and the housing 4 is prevented by friction of the ring 59 against the bearing nut of body 33, contact between these parts further preventing entry of dirt into the interior of the device.

If it is desired to prevent free rotation of the load supported by the hook, the handle 41 is actuated to rotate the lever 44 into the position shown in Fig. 3, in which the inner end of the lever engages one of the slots 4!, thereby preventing rotation of the body It relative to the shank i5. 0n the other hand, if it is desired to permit free rotation of the load, the handle 41 is actuated to rotate the lever 44 in the opposite direction to carry the inner end of the lever clear of the head 28 and the slot 43 therein. The lever 44 is retained in either position to which it may be moved by friction between the bolt 49 and the cam surfaces 55 and 5B. When the lever 44 is disengaged from the slots 43, the body 13 is free to rotate with respect to the shank i8; hence its-only contact therewith is through the bearing member comprising the

races

39 and 40 and the smooth surfaces on the upper end of the body 38 and the lower face of the ring 59, respectively.

when it is desired to employ the hook with an elevator having two balls, the latter may engage with the arms i 01 by first pulling out on the lever Ill and upwardly on the lever ill to release the arms ill and then swinging the latter outwardly in substantially horizontal position in which they will be automatically retained by lugs III on the levers H9 and the lugs II! on the arms iiifl. The

elevator balls are then placed in position on the arms i" and the arms llil closed by lifting the levers ill to disengage the lugs if! from the lugs I28 and moving the arms I08 into closed position in which they are locked by engagement of the lugs ill on the levers HQ with the lugs I" on the arms I08 and by the positioning of the fingers III on levers H4 in juxtaposed relation to the lugs I22 on levers H9.

Although the inventionhas been explained by describing in detail a particular structure in accordance therewith, it is to be understood that various modifications can be made in the particular structure shown without departing from the invention, and the latter is to be limited only as set forth in the appended claims.

We claim:

1. A book structure comprising a hook member for engaging a load, a supporting member for supporting said, hook member, a pair of bearing elements having complementary spherical contact surfaces relatively slidable' on each other, means connecting one of said bearing elements to said supporting member, and means connecting. the other of said bearing elements to said,

hook member, in which at least one of said connecting means comprises antifriction bearing means rotatably interconnecting the bearing element and member associated therewith.

2. A hook structure comprising a hook mem her for engaging a load, a supporting member for supporting said hook member, and means interconnecting said members for relative swinging movement comprising a stem on one of said members, and a head on said stem having a spherical bearingsurface, an annular element on said other member bearing against said firstmentibned spherical surface, and thereby preventing separating movement of said two members while permitting relative oscillation therebetween in any direction, in which said annular element comprises a pair of bearing members relatively rotatable with respect to each other about the axis of said annular element whereby said hook member can rotate relative to said supporting member about the axis of said annular element, independently of movement along said spherical surface.

8. A hook structure comprising a hook member for engaging a load, a supporting member for supporting said hook member, and means interconnecting said members for relative swinging movement in any direction, comprising a stem on one of said members and a head on said stem having a concave spherical bearing surface thereon, an annular element on said other member having a convex spherical surface bearing against said concave spherical surface on said head and thereby preventing separating movement of said two members while permitting relative oscillation in any direction.

4. A hook structure as described in claim 3, in which said annular element has a second convex spherical bearing surface on the opposite side thereof from said first mentioned spherical surface, said second surface having the same swinging center as said first surface, and means connected to said stem and juxtaposed to said second convex surface for limiting separating movement of said first mentioned spherical annular member and head.

5. A hook structure as described in claim 3, in which said'annular element has a second convex spherical bearing surface on the opposite side thereof from said first mentioned spherical surface, said second surface having the same center of curvature as the first-mentioned surface, and resilient friction means connected to said stem and bearing against said second mentioned spherical surface on said annular member for damping movement between said two members.

6. A hook structure comprising a hook member for engaging a load, a supporting member for supporting said hook member, and means interconnecting said members for relative swinging movement in any direction comprising a stem on one of said members, a head on said stem having a spherical bearing surface, an annular element on said other member bearing against said spherical surface and thereby preventing separating movement of said two members while permitting relative oscillation therebetween in any direction and in which said annular element comprises two members, bearing means of the rolling contact type interconnecting said members for relative rotation about the axis of said annular element, a second spherical surface on said annular element opposite said first spherical surface thereon, and having the same center of curvature, and means connected to said stem for resiliently contacting said last-mentioned spherical surface and frictionally resisting rotation of said hook member relative to said supporting member.

7. A book structure comprising a hook member for engaging a load, and a supporting member for supporting said hook member with means interconnecting said members for relative swinging movement in any direction comprising a stem on said supporting member, a head on said stem having a spherical bearing surface thereon, said hook member comprising a hollow body receiving said stem and head and having an opening in the upper end through which said stem extends, and means connected to said stem for engaging and sealing with the outer surface of said body all the way around said opening in all relative positions of said supporting member and said hook member, said body member including an annular member having a spherical surface engaging said spherical surface on said head for supporting said body on said stem for swinging movement relative thereto.

8. A hook structure as described in claim 7 in which the outer surface of said body adjacent said opening therein is spherical about the same center of curvature as said first mentioned spherical surface, and means connected to said stem and juxtaposed to said last mentioned spherical bearing surface on said body for limiting separating movement of said first mentioned spherical surfaces.

9. A hook structure comprising a hook member for engaging a load, a supporting member for supporting said hook member, and means interconnecting said members for swivel movement therebetween comprising a stem on said supporting member, a head on said stem, means on said hook member engaging said head, whereby said hook member is suspended from said stem, said stem having a vertical recess therein, a bolt, and means mounting said bolt on said hook member for substantial radial movement into and out of engagement with said recess in said stem to lock and unlock said member with res ect to relative swiveling motion therebetween.

10. A device as described in claim 9, in which said bolt comprises an arm on a shaft, means for supporting said shaft for rotation, and a handle exterior of said hook member and connected to said shaft for rotating the latter into and out of engagement with said recess in said stem.

11. A hook structure as described in claim 9, in which said bolt comprises a shaft rotatably mounted in said hook member with an arm on said shaft having a portion extending substantially radially from said shaft and an end portion extending singularly from said first mentioned portion for engaging said recess in said stem with a spring detent in the end of said first mentioned radial portion of said arm, and cam means on said hook member adapted to depress said detent during movement of said arm from position in engagement with said recess to position clear of said recess for frictionally retaining said arm in whichever position it has been moved.

12. A hook structure as described in claim 9, in which said hook member comprises a hollow housing containing said recessed stem, said housing having an aperture therein with a detachable cover plate secured to said housing over said aperture, and means for supporting said bolt on said cover plate.

13. A book structure comprising a hook member having an upwardly extending stem thereon. a head on said stem adjacent the upper end thereof, a supporting member for supporting said hook member comprising a housing surrounding said stem and slidable vertically therealong, means for applying a lifting force to the upper end of said housing, spring means interconnecting the lower end of said housing and said head on said stem for transferring small lifting forces applied to said housing from said stem, said spring means yielding in response to heavy forces to permit sliding movement of the housing downwardly along the stem, and means for limiting such movement and applying lifting force from said housing directly to said stem, comprising shoulder means on said stem and cooperating shoulder means adjacent the upper end of said housing adapted to abut against said shoulder means on said stem, whereby the portion of the housing below said shoulder means thereon is subjected only to the small lifting forces applied to said hook member through said spring.

14. A hook structure as described in claim 13 with swivel means interconnecting said stem to said hook member for unyieldably supporting said hook member with respect to said stem, while permitting rotary and swinging movement of the latter.

15. A hook structure as described in claim 13, with a sleeve slidable on the lower portion of said housing and sealing therewith, means fixing said sleeve with respect to said stern for vertical movement therewith, and means for effecting a seal between the lower end of said sleeve and said hook member.

16, A hook structure as described in claim 13, in which said hook member comprises a hollow housing, swivel means within said housing interconnecting said stem to said hook member for permitting rotary and swinging movement of the hook member with respect to said stem, a sleeve slidable on the lower portion of said first mentioned housing and sealing therewith, means flxing said sleeve with respect to said stem for vertical movement therewith, and means for effecting a seal between the lower end of said sleeve and said second mentioned housing on said hook member, whereby both said housings are retained in sealed condition irrespective of relative movement between said stem and said 17. A hook structure comprising a hook member for engaging a load, a supporting member for supporting said hook member, a stem on one of said members, bearing means on said stem. and an annular element on the other oi said members having as phericai bearing surface bearing against said bearing means on said stem for supporting said hook member for swinging movement but agaiinst separating movement with respect to said supportin member, in which said annular element has a second spherical bearing surface having the same center of curvature as the first-mentioned spherical surface thereon, but oppositely disposed therefrom, and said stem has means connected thereto and juxtaposed to said second spherical surface on aid annular element for limiting separating movement between said first-mentioned spherical surface on said annular element and said bearing means on said stem.

18. A hook structure comprising a hook member tor engaging a load, a supporting member for supporting said hook member, a stem on one oi said members, bearing means on said stem, and

CERTIFICATE Patent No 2,158 252.

HERBERT E an annular element on the other of said members having a spherical bearing surface bearing against said bearing means on said stem for supporting said hook member for swinging movement but against separating movement with respect to said supporting member, in which said annular element has a second spherical bearing surface having the same center of curvature as the first-mentioned spherical surface thereon and said stem has means connected thereto for resiliently contacting said second spherical surface on said annular element and irictionally reisting rotation 01 said hook member relative to said supporting member.

19. A hook structure comprising a hook member for engaging a load, a supporting member for supporting said hook member and including a housing, a coil compression spring mounted in said housing, a stem siidabiy and yieldabiy supported by said spring and extending through the lower end of said housing, and connecting means comprising a ball and socket connection between said hook member and said stem.

HERBERT E. GRAU. RICHARD K. HERTEI...

F CORRECTION.

Hay 16, 193.9

.GRAU, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 8, first column, lineB, claim'l'l, for "as ph'erical" read a spherical; line 11, for

"agailnst" read against; fine 12, for "supportin' read line 18, same claim 17, for the word "aid' read supporting; and said; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the *case in the Patent Office. Signed and sealed this 7th day of November, A. D. 1939.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents.

relative movement between said stem and said 17. A hook structure comprising a hook member for engaging a load, a supporting member for supporting said hook member, a stem on one of said members, bearing means on said stem. and an annular element on the other oi said members having as phericai bearing surface bearing against said bearing means on said stem for supporting said hook member for swinging movement but agaiinst separating movement with respect to said supportin member, in which said annular element has a second spherical bearing surface having the same center of curvature as the first-mentioned spherical surface thereon, but oppositely disposed therefrom, and said stem has means connected thereto and juxtaposed to said second spherical surface on aid annular element for limiting separating movement between said first-mentioned spherical surface on said annular element and said bearing means on said stem.

CERTIFICATE Patent No 2,158 252.

HERBERT E. GRAU. RICHARD K. HERTEI...

F CORRECTION.

Hay 16, 193.9

.GRAU, ET AL.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents.