US1734330A - Traversing hoist - Google Patents

Description

.'Nv. 5, 1929A G. A. GRAB TRAVERSING HOIST Filed March l, 1927 l 5 Sheets-Sheet NL IKN Nov. 5, 1929. G. A. GRAB TRAVERS ING HOIST Filed March l. 1927 /qTrnR/vev/ l 3 Sheets-Sheet Nov. 5, 1929. G. A. GRAB TRAVERSING HoIsT Filed March l, 1927 Patented Nov. 5, 1929 UNITED STATES GUSTAV A. GRAB, yOF PORTLAND,

PATENT OFFICE STEEL WORKS, OF PORTLAND, OREGON TRAVERSING HOIST Application ined March i,

This invention relates generally to traversing lio-ists, and particularly to the self-propelled type designed for surface operation and especially intended for the handling of objects by straddling saine and then picking 1 them up bodily, with special reference to the handling of piled lumber.

The first object ofthis invention is to provide an exceedingly simple and efficient traversing hoist having combined swinging and lifting arms by means of which the load can be engaged and suspended. y

The second object is to provide a special type of lifting mechanism employing a selfopposed horizontal lifting screw.

T he third obj ect is to provide a positive upward and downward feed Jfor the lifting mechanism. y n

The fourth object is to so construct the hoist that it can lift its wheels bodily olf from the ground for the purpose of extracting same from ruts, replacing the tires, or working on the wheels.

The fifth object is to employ one pair of opposed lifting frames of a iiexible nature which will permit the proper engagement with a load and the ultimate alinement of the load with the hoist before the load is lifted.

The sixth object is to secui'e great rigidity of the parts while carrying the load and flexibility in the load lifting' parts while in the lowei'most portion of their travel.

The seventh object is to provide a hoist having its lifting ymembers possessed of longitudinal rigidity and lateral iiexibility.

The eighth object is to so construct the hoist that it will be impossible to operate the lifting mechanism until the load is properly engaged, or in an innermost position.

The ninth object is to provide a power; driven lifting kmechanism and a manually operated load engaging mechanism within easy control of the operator, making it possible for one operator to easily handle the inachine and pick up or place a load in any desired position.

The tenth object is to provide equalizing means for the connections which urge the exi927. sei-iai No. 171,748.

treme ends of the lifting angles toward the load.

The eleventh object is to provide a yielding connection between the lifting' mechanism and the load supporting angle in order that slight obstacles in the road bed can be overcome by the bodily lifting of one corner of the load supporting frame without the actual raising of the hoist itself or subjecting same to unusual shocks.

The twelfth object is to provide a hoist whose load-supporting and lifting members will not be rendered inoperative due to continued rough usage and shocks imposed thereon by the ei'icountering of obstructions and the quick starting and stopping of the load.

These, and other objects, will become more apparent from the specication following as illustrated in the accompanying' drawings,

in which:

Figure 1 is a side elevation of the traversing hoist. F igui'e 2 is a longitudinal section through the double end thrust bearing of the lifting screw. Figure 3 is a plan showing the lifting device and equalizing parts. Figure 4 is a vertical section taken along the liiie 1*4 iii Figure 3. Figure 5 is a horizontal section tal-:en along the line 5-5 in Figure 1. Figure 6 is a vertical section taken along the line 6-6 in Figure 3. Figure 7 is a horizontal section taken along the line 7 7 in Figure G. Figure 8 is aA transverse section taken along the iine 8-8 in Figure 1 showing' the hoist straddling a load preparatory to engaging saine. Figure 9 is a view f similar to Figure S showing the lifting dog moved into position against the load ready to start the lifting action. Figure 10 is a view similar to Figure 9 showing the load lifted. Figure 11 is a perspective view of the cross head guide. Figure 12 is a horizontal section taken along the line 12-12 in Figure 1.

Similar numbers of reference refer to similar parts throughout` the several views.

Referring in detail to the drawings, there is illustrated a traversing hoist including the wheels 10, steering spindles '11, spindle brackets 12 and longitudinal fiames 13, 14 and 15 which are joined by the cross frames 16, 17 7 1S and 19. The outline of an engine parallel with the members l and operatoras seat 2l are also indicated.

On each side of the hoist, near each end thereof between its wheel members l0j are secured the spaced upright guides 22 consist-- ing of inturned angles which are seemed to the members l, le and l5 by means of the clips 23. To the outer sides of the members 22, extending between the members i3 and 149 are the out-turned angles 2e which act as locks preventing the release of the load beiore it is otherwise supported.

Mounted between the inner members 22 is a cross liead l an elongated vertical slot- 26. I 25 is attached by means of a li* lower end 28 of a bell cranlr lever 29, whic pivotally mounted on the bracket- 30 wlii is attached to an upright frame member i The upper end of the bell cranl lever jointed by a link 32 to a nut 32E on the three end 3l of the shaft 35 provided with a douoie hrust bearing 36 which may be c nbined in one, or otherwise positioned as seems The shaft is supported in bearings 87 on the frame 13.

ln the slot 2G is placed a pin pivotally supports one end of the load snpporting framey which consists of a pair upright angles 39 reinforced by the arides and attached by the vertical pivo s el to die load supporti 1 angle 12 'oy mo interposed brzmiet e y i c high at its middle movement betweenL and its attached load support' It will be understood tha bers 17 provide only longr but are laterally flexible, at lea so to permit the ends of frames to move laterally with relatio= other-that is7 tlie rearward end o frame can move laten `ly indepenne its forward end, and vice versa. Ubvioosv if the sides #il were made straigns-tha; is,

fail to bacli up the side of trie member e' or would otherwis clamp rigidly to the uprights 3S), in which lateral i@ "ibility would be eliminated, which is one oi L; e L sons existing types of lioists employ separate shoes7 else employ laterally ri ji load lifting shoes.

It will be understood that a sinilar arrangement of p t each end s is positioned of the load supporting angle and that is a load support-ing angle on each side o hoist7 also that the load supporti. face each other for the purpose of the under side of the bolster end which lumber e6, or other objects,

'On top of the frames l7 and 18 i the plates e7 ipon each of which mounted a lever el@ on the pivot e9. Gn the end of each :arse eso lever l is mounted a floating lever 50 to whose nembers ,5l and 52 are attached the connecting rods which extend laterally to the pivotal connections 5e wiich, in turn7 carry the rollers 55 operating in a tee slot in the member 56 secured to the upper end of the loat supporting frame. Similar parts 47 to connect transversely the other ends of the opposite frames.

. Tae shafts 35 are provided with right and left threads at their opposite ends and the two are provided with the sprockets 57 are connected by the chains 58 to the ets 59 from the Clutch power shaft 60 which. is provided with an upright clutch control lever 6l in whose path is placed a springu pin G2 which is normally held out of of the lever 6l by its spring. On the p dinal frame member 63 is mounted an uprigntsnaft (3l to which is attached a two armed lever 65 from whose arms extend the rods 65 to the floating lever 50. aft be is mounted in a longitudinal slot mit-ting saine to nieve forward or rrd to equalize the pulls on the forward in rard floating levers 50, each of which 'l vn. iualizes the pulls of the laterally exto engage the pin G2 when the lever 69 is pushed away from the operator, causing the end of the pin 62 to intercept the clutch lever 6l. in other words-the lever G9, whose movement way from the operator causes the load supporting angles to spreadawa-y from the load prevents the clutch lever Gl which controls the application of power to the lift-ing mechanism, from being operated; but when the lever 69 is pulled toward the operator and the load is engaged it is possible to move the clutch lever 61 to an operating position.

ln other words-if the operator wishes to piclr up a load l e must lirst talre hold of it by neans of the shoes L l2 which he must place under the ends Ll5 of the bolsters. To do this the operator pulls the lever 69 toward him-that is, away from the position shown in Figure 3, which will ycause the push rods 53 to move outwardly and the lower ends of the load lifting frames to spring inwardly. bviously, this will permit the pin 62 to clear the clutch control lever 6l and allow the operation of the lifting mechanism. Since the cam 68 must free the pin 62 it follows that if for any reason the shoes 42 do not pass under the ends Ll5 of the bolsters then the lever 69 cannot be operated suliiciently far toward the driver to 'permit an attempt at lifting the load.

lt is preferable to provide a guide 7() for the upper side of each rod 53, since tnese would otherwise move upwardly when the load was being raised causing a change in 'regres theiry length and a consequent lateral movement of the load supporting angles 42.

N o attempt has been made toelaborate on details not intimately connected 'with this in-` vention, and it is not intended that the precise forms of elements herein illustratedare essential to the operativeness ofthe hoist. It is a well knowny fact that many yforms of traversing hoists have been constructed kin the past in which four independent load supporting arms were swung beneath the frames of such machines. In many instances these were rigidly connected `together `by mechanical operating means, and in-other instances they have been ymade separately operable and yielding. f In this instance, however, a load supporting angleis placed on each side of the load, and while this angle is flexible or yielding as to angularity for the purpose of adapting itself to the relation between the hoist and a load about to be picked up, these angles are not capabley of endwise movement with relation to the hoist itself. In other words-any jars or impacts which would tend to move the angles 42 longitudinally are transferred directly to the cross heads which are rigidly guided in the frame of the hoist, and the load supporting frames themselves are rigidly braced longitudinally with relation to the load supporting angles, by ymeans of the braces 7l which are relatively thin and fief;-`

ible.

It can now be seen that should the hoist be run straddling over the top of a pile of lumber, although not exactly in line with samek (as is most often the case) that the operator havin stopped the hoist near the middle of the pi e now pulls the lever 69 toward him,

which tends to draw the laterally opposed corners ofthe load supportingangle toward each other. Obviously, if the load is out of line with the hoist, one corner of the angle will engage the bolster end45 before its mates. At this point the lateral equalization of the parts occurs at the end of the hoist, first to engagethe load, and the same operation` then transpires at the opposite end of the hoist; and added to this equalization feature is the fore and aft equalization through the rod G6, which makes it certain that the load supporting angles will assume their proper' relation to the bolsters which support the load, as, for example, as shown in Figure 9.

It will be noted in Figure 8 that the point 72 of the load supporting` frame does not bear against the angle 24 at this time, but is below the end of same and is above the pin 38, which makes it possible for the angle 42 to swing outwardly between the wheels l0. However, when the angle Ll2 has been moved to the position shown in Figure 9 by means of the lever 69 and the pin 62, which locks the clutch lever 6l, is therefore withdrawn,

24, making it impossible for same to spread at its lower ends sufficiently to allow the load to escape and fall to the ground.

Again, it will be notedfin Figure 9 that if, for any reason such as irregularities in the roadway or otherfactor, one corner of the load supporting member should be raised, that such action will be possible without serious consequences, owing to the slot 26 which permits the pin 38 t0 rise therein without exerting alifting' action on the frame itself, at least for a predetermined distance, which is suilicient to take care of all ordinary contingencies. n

It is perferable in some instances to provide a guide 7 3 for the upper sides of the nuts 83 to take care of the upward thrusts against the shaft 35 between its bearings 37. In Figure 2 is illustrated a double end thrust bearf tween the cross heads and their guides, or the wheels were being lifted up by placing a bolster under the load supporting angles for the purpose previously mentioned, in which case the shaft would be placed in compression.

hile the members 73 are useful in providin g lateral reinforcement for the shaft 35, their main function is to prevent the rotation of the nuts 33 on ythe threaded portion of the shaft 35. f f

It will be understood that the object in preventing the occurrence of any lifting action before the yload supporting frames are in their proper position-that is,'e.itherengaging a load or in their innermost positions, is because even if it werey possible to apply the lifting action when the lower ends of the load supporting frames were not in their .innermost position, such lifting action would result in a gradual forcing in of the load engaging members due to the fact that the point 72 will ride upon the members 2st. This would f result either in splitting the object between the load supports or seriously damaging the operating mechanism, and in all probability it would be the latter of these two conditions.

It can be readily seen that, due to various conditions such as depressions in the ground, poorly piled. loads, trash or other obstacles, may prevent the load supporting angles from passing under the ends l5 of all of the 1'eolsters. Especially at night is the operator unable toobserve such conditions closely, and theresult is that if he undertakes to lift an improperly engaged load the engaging members merely claw' up the sides of the pile and tend to further disrupt same, or else seriously injure the mechanism, as above stated.

It is for this purpose that there is provided the clutch lever intercepting pin 62 which renders it a physical impossibility to lift the load unless all of the holsters are properly engaged.

I claim:

1. In a traversing hoist, the combination of a wheeled straddle frame having vertical guides on the sides thereof; a cross head in each of said guides; a laterally flexible and longitudinally rigid load supporting frame at each side of said frame hingedly mounted at its forward and rearward ends on said cross heads; and a load supporting angle attached to the lower end of said load supporting frame by means of pivotal connections adapted to permit independent lateral movement of the forward and rearward ends of said frame.

2. In a traversing hoist, the combination of a wheeled straddle frame with a pair of spaced vertical slides at each side of said frame; a cross head in each slide; a longitudinalrrigid frame rhinged near the middle of its height to said cross heads, the lower ends of said frame having a load supporting angle attached thereto by means of vertical pivots adapted to permit independent lateral movement of the ends of said frame; and means incorporated in said slide for preventing outward swinging of the lower end of said frame when in a raised position.

In a traversing hoist the combination of a wheeled frame having a vertical slide near each uppercornerthereof, a cross-head mounted in each slide said cross-heads having means for positively operating same in unison upwardly and downwardly, each slide having an extension guide thereon, a longitudinal load supporting frame along each side of said hoist hinged to said cross-heads, a longitudinal foot extending across the lower ends of each load supporting frame, said load supporting frame having portions thereof above its hinge adapted to engage said extension guide when raised in a manner to prevent an outward movement of the foot q of said load supporting frame, said upwardly extending portion thereof clearing said extension guide in a manner to permit the outward swinging of said load supporting frame in a lowered position.'

Ll. In a traversing hoist the combination of two pairs of laterally disposed spaced ver tical guides arranged in tandem with a crosshead mounted in each of said guides having means for positively operating same in both vertical directions, a unitary load supporting frame between each lateral pair of crossheads consisting of two upright end members having laterally flexible longitudinal braces between same, a longitudinal load supporting angle uniting the lower ends of each load supporting frame, said end menibers being adapted to permit lateral flexibility of movement of said load supporting angle, said uprights having hinged connections to said cross-heads adapted to permit a limited amount of free upward movement to either end of a load supporting frame, means for locking said load supporting frame against outwardly swinging movement as soon as it begins to rise, and means for preventing the operation of said cross-heads unless both of said load lifting frames are in a load engaging position along their entire lengths.

5. In a traversing hoist, a load lifting mechanism consisting of a horizontal threaded shaft having a pair of nuts mounted thereon, a bell crank lever mounted under each nut, a cross-head under each bell crank lever, connecting links between each nut and cross-head and its bell crank lever, and means for suspending a load from said cross-heads.

G. In a traversing hoist, a load lifting mechanism consistingof a horizontal shaft having opposite threads formed thereon; a nut on each of said opposite threads; a bell crank lever under each of said nuts; a vertically slidable cross head under each of said bel crank levers; link means between each of said bell crank levers and its associated crass head and operating nut; and means for rotating said shaft.

i'. In a traversing hoist, a load lifting mechanism consisting of longitudinally spaced vertical guides att-achable to the hoist; a cross head mounted in each guide; a unitary load supporting frame hinged near the middle of its height to said cross heads, said frame having longitudinal rigidity over its entire area and lateral flexibility at the lower load engaging end thereof, the upwardly extending ends of said frame having equalized lateral thrust rods attached thereto for the purpose of swinging the load engaging end of said frame inwardly; a power driven horizontal shaft mounted above said cross heads having opposite threads formed thereon over the two cross heads, each of said threadet portions having a nut thereon provided with operatingbell crank levers and links whereby a rotative movement of said shaft which moves said nuts toward each other will raise said cross heads.

8.l In a traversing hoist, a load lifting mechanism consisting of longitudinal spaced vertical guides attachable to the hoist; a. cross head mounted in each guide; a unitary load supporting frame hinged near the middle of its height to said cross heads, said frame having longitudinal rigidity over its entire area and lateral flexibility at the lower load engaging end thereof, the upwardly extending ends of said frame having equalized lateral thrust rods attached thereto for the purpose of swinging the load engaging ICO ' links whereby a rotative movement of said shaft which moves said nuts toward each yother will raise said cross heads; and clutch means between said shaft and its source of power having means for locking same out of engagement when said load supporting frame is not in a complete load engaging position.

9. In a traversing hoist7 the combination of a wheeled frame having two pairs of vertical guides attached thereto in parallel longitudinal planes; a cross head in each guide; a unitary frame having longitudinal rigidity and lateral flexibility hinged across both of said cross heads above the middle of the frame height; a horizontal self-opposed screw mounted on said frame above said cross heads; a nut on each end of said screw, a bell crank lever under each nut; link means for operatively connecting each bell crank lever to its cross head; and equalized connecting rod means for moving the lower corners of said load supporting frame into a load engaging position; said equalized means forming a lock for preventing the operation of said cross frame; a cross-head in each of said slides, a longitudinal load lifting frame hinged along s each side of said hoist to the cross-heads above same, each of said load lifting frames having their upper ends projecting above their points of hinging; floating levers between the forward and rearward upwardly projecting ends of said load lifting frames, bell crank levers mounted on said floating levers; push rods between said bell crank levers and the forwardly projecting ends of said load lifting frames, a second floating lever between said first mentioned lloating levers having connecting rods between same and said bell crank levers; lever means for actuating said second mentioned floating lever, a cam operated by said second mentioned floating lever7 and means actuated by said cam for preventing vertical movement of said cross-heads when said load lifting frame is not in a load en- @faminer position. t D eUsTAv A. GRAB.

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