US2375800A - Mobile crane - Google Patents

Description

May 15, 1945. Re. LE TOURNEAU MOBILE CRANE Filed. Jan. 22, 1944 2 Sheets-Sheet l iNvENToR R.G.ll'7urzzaau.

' A'rrrs y 1945- R. G.'LE TOURNEAU Q 2,375,800

MOBILE CRANE Filed Jan. 22, 1944 2Sheets-Sheet 2 INVENTYOR WWI;

A TTYS R. G. LeTe'aurneaaa Patented May 15, 1945 MOBILE CRANE Robert G.- Le Tourneau, Peoria, 11L, assignor to R. G. Le Tourneau, Inc., Stockton, Calii?.,v a corporation of California Application January 22, 1944, Serial No; 519,327

11 Claims.

This invention relates in general to an imroved mobile or portable crane, and in particular the invention is directed to, and it is an object to provide, a self-propelled mobile crane which includes a foldable mast and boom assembly whereby for transport of the crane from place to place said mast and boom assembly may be folded so as to not require any great head clear- .ance.

A further object of this invention is to provide a crane as above which is self-erecting; the crane including an engine actuated winch, and there being operating connections between said winch and the mast and boom assembly whereby to raise said assembly from a folded position to an erect position.

An additional object is toprovide a crane as above in which said operating connections include a unique cable system operative to control lowering and folding movement of the mast and boom assembly, and to cause unfolding and erection thereof.

Another object of the invention is to provide a crane which comprises an engine propelled vehicle, a normally upstanding mast, means pivoting said mast at its lower end on. the vehicle for swinging movement to a lowered position, releasable holding means normally preventing such lowering movement of the mast, a normally outwardly projecting boom pivoted in connection with the upper end of the mast for downward folding movement to a lowered position against the mast, releasable holding means normally preventing such downward folding-movement of the boom, and engine actuated means connected with said mast operative to control lowering movement of said mast from an, erected position to a lowered position, and to raise the mast to said erected position from said lowered position.

A still further object of this invention is to provide a crane, as in the preceding paragraph,

in which said engine actuated means is operative.

to control folding of the boom after the mast is in said lowered position and said boom holding means released, and to raise said boom to normal position for resetting of said boom holding means prior to erection of the mast.

A further object of the invention is to provide a simple and inexpensive device, and yet one which is exceedingly eiiective for the purpose for which it is designed.

These objects I accomplish by means of such structure and relative arrangementof parts as will fully appear by a perusal of the followin specification and claims,

In the drawings similar characters of reference indicate corresponding parts in the several views:

Figure 1 is a side elevation of the crane showing, in full. lines, the mast and boom assembly erected, and showing, in broken lines, said" assembly in partially lowered position.

Figure 2 is a side elevation of the crane taken from the side op osite Fig. 1, showing the mast fully lowered; the boom being shown in full lines in a artially folded position, and in broken lines in a fully folded position.

Figure 3' is a fragmentary rear end view of the crane.

Figure 4 is a fragmentary plan view of the carriage and control brace unit.

Figure 5 is a diagrammatic view of the cable system.

Referring now more particularly to the characters of reference on the drawings, the crane comprises an elongated horizontal body-forming beam I of substantial length, which is disposed adjacent but clear of the ground. At its rear end thebody l includes a horizontal, transversely extending rear axle housing 2 in rigid relation;

is connected at its forward end by draft means,

shown in part at 4, with the rear end of a'tractor, indicated generally at 5, and which is here shown as a two-wheel type tractor having an operator's seat 8 disposed adjacent but ahead of the yoke 3. The tractor 5 is connected to the yoke 3 in vertically inflexible but horizontally steerable relation.

A mast, indicated generally at I, normally upstands from thebody I adjacent its rear end and is pivoted on the wheel axles between the wheels and housing 2, as at P. Said mast comprises a. pair' of transversely spaced, upwardly converging legs 8, and another pair of corresponding legs 9 which are connected at' their lower ends with the corresponding ends of legs 8' and thence extend upwardly in converging" relation to each other but in forwardIy' diverging relation to the legs 8'. At their upperends thelegs 8 and 9 are connected in rigid relation by a cage-like bracing assembly or skeleton head [0. Below the head H] the legs 8 and 9 are connected by suitable bracing, as

shown.

The mast I is fitted at its upper end with a rearwardly projecting normally substantially horizontal boom II which comprises upper and lower pairs of transversely spaced arms, indicated generally at I2 and I3 respectively, said arms projecting outwardly in converging relation. At their outer ends the arms l2 are fixedly secured together, and at their inner, spaced apart ends said arms are connected in rigid relation by bracing Ila. The lower arms I3 of the boom, II are pivotally connected at their inner ends, as at I4, at transversely alined points, in connection with corresponding portions of the head I0, whereby the boom II can fold downwardly into engagement with the mast I. However, such downward movement is normally prevented by means of removable pins I5 which connect the inner ends of boom arms I2 with corresponding portions of the head I0. When the pins I5 are in place, the boom II is rigidly secured in outwardly and rearwardly projecting relation to the mast I.

The mast l is normally maintained in vertical or upright position by means of a pair of rigid braces I6, which are pivotally connected, as at I1, to the front of corresponding legs 9 intermediate the ends of the latter; the braces I6 extending forwardly and downwardly in converging relation to fixed but pivotal connection at their lower ends with a carriage, indicated generally at I8. The carriage I8 includes a roller I9 which rides on top of the body I, and opposed, laterally projecting trunnions 20 which normally seat in forwardly and horizontally opening yokes or cradles 2| fixed on and upstanding from the body I, in transversely spaced relation. Escape of said trunnions from said yokes is normally prevented by means of removable cross pins 22 which extend through the legs of said yokes and intersect the opening thereof in front of said trunnions.

As is evident, removal of cross pins 22 will permit the carriage I8 to run forward on the body I,

with resultant forward and downward swinging movement of the mast I to the lowered position shown in Fig. 2, and in which position the upper end of the mast engages and is supported by a shock absorber stop 23 fixed on and upstanding from the top of draft yoke 3, With the mast in lowered position, as in Fig. 2, the pins I5, at the inner end of the boom l I, are accessible to the operator and uponwithdrawal of said pins the boom can be folded downwardly against the lowered mast, to a folded position, as shown in broken lines in Fig. 2.

Lowering of the mast and folding of the boom is controlled by a cable system which is also operative to unfold the boom and to raise the mast to an erected position; such cable system comprising the following:

A power winch, indicated generally at 24, is mounted on the rear end of the tractor within the yoke 3, said power winch including a pair of cable drums, indicated at 25 and 26, respectively, said drums being selectively operable by the driver 'of the tractor. The power winch 24 is of such type that the paying out of the cables from the drums is controlled by an internal, operator regulated brake (not shown).

. A cable 21 leads from the drum 25 through a fairlead assembly, indicated generally. at 28, mounted on one side of the yoke 3, and from said fairlead assembly the cable .21 extends. down: wardly and about a fixed sheave 28a on'the lower end of yoke 3. From, the sheave 2811 cable 21 extends rearwardly along and adjacent the body I to and about a sheave 29 fixed in connection with the body I adjacent its rear end, and thence the cable includes a forwardly extending loop 30 which passes intermediate its ends about a sheave 3| fixed in connection with and projecting rearwardly from the carriage I8; the cable passing from said loop about another sheave 32 on the body alongside of sheave 29 and then extends upward through the mast I. At a point adjacent the upper end of the mast, the cable 2'! turns about a sheave 33 and passes rearwardly through the boom and over a swinging sheave'34 depending from the outer end of said boom. From the swinging sheave 34 the cable depends in block and tackle relation to a sheave 35 included in a lifting hook unit 36. At the rear end the crane body includes an eye 31 into which the hook 36 is adapted to be engaged preparatory to lowering of the mast 1.

Another cable 38 leads from the drum 26 of winch 24 through a fairlead assembly, indicated generally at 39, secured on the corresponding side of yoke 3. From the fairlead assembly 39 cable 38 extends rearwardly and upwardly over guide sheaves 40 fixed in th skeleton head Ill of the mast and thence continues and passes over a sheave 4I fixed in the rear end portion of the boom I I some distance above the pivots I4. After passing about the sheave 4I the cable 38 extends forwardly and over another guide sheave 42 in head I0 and thence is reeved, as a block and tackle T, between a sheave 43 on the upper end of yoke 3 and a sheave 44 in the head I0, being dead-ended to the frame of sheave 43, as at 45.

In order to lower the mast I and to fold the boom II from normal operative position, the following operations take place:

The hook unit 36 is first lowered and engaged with eye 31, and then the cross pins 22 are removed from the yokes 2|. Thereafter, drum 26 of the winch 24 is operated to wind in the cable 38, which results in shortening of the block and tackle T and forward and downward swinging movement of the mast. In order to prevent the mast from falling forward too rapidly, the cable 21 is simultaneously retained relatively taut and paid out at the desired speed, which controls forward movement of the carriage I8. It will thus be seen that the operator, by winding in cable 38 onto drum 26 and paying out cable from drum 25 at a controlled rate, can lower the mast I with nicety.

After the mast reaches its lowered position in engagement with the shock absorbing stop 23, the operator locks drum 2G and then withdraws the pins 25 at the inner end of boom II. When said pins have been withdrawn the operator again takes his position on the tractor and slowly pays out the cable 38 from the drum 26, which permits the projecting boom II to gradually fold rearwardly and downwardly until it engages the lowered mast, as shown in dotted lines in Fig. 2. As the boom folds downwardly, the resultant slack in cable 21 is wound onto drum 25.

' To unfold the boom and erect the mast, the above procedure is merely reversed.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice suchdeviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

i 1 Having'thus described'my invention, .what'I claim .as new and useful and desire to secure by Letters Patent is:

1. A crane comprisimg a longitudinally extending body supported for movement along the ground, a mast normally upstanding from the body, means pivoting the mast in connection with thebody for downward swinging movement to a lowered position, releasable holding means normally preventing swinging movement of the mast, a boom normally projecting outwardly from the lectively permit the boom to drop to folded position or to pull it to its normal extended position when the pin is removed.

2. A crane comprising a longitudinally extending wheel-supported body connected in draft relation with a tractor including an engine actuated winch, the winch including multiple cable drums, a mast normally upstanding from the rear end portion of the body, means pivotingthe mast in connection with the body for forward and downward swinging movement to a lowered position, releasable holding means normally prevent-ing such swinging'movement of the mast, a boom normally projecting outwardly from the upper end portion of the mast, means pivoting the boom to connection with the mast for downward folding movement, other releasable holding means normally preventing folding of the boom, and a cable system including a cable leading from each drum of the winch to the mast and boom assembly, said cable system being arranged so that one cable is operative to control swinging of the mast to a lowered position and folding movement of the boom, and the other cable is operative to raise the mast from a lowered to an erected position.

3. A crane as in claim 2 in which said one cable is arranged to effect unfolding movement of the boom when the mast is in said lowered position.

4. A crane comprising a longitudinally extending wheel-supported body connected in draft relation with a tractor including an engine actuated winch, said winch having a pair of selectively controlled cable drums, a mast normally upstanding from the rear end portion of the body, means pivoting the mast in connection with the body for forward and downward swinging movement to a lowered position, releasable holding means normally presenting such swinging movement of the mast, a boom normally projecting outwardly from the upper end portion of the mast, means pivoting the boom in connection with the mast for downward folding movement, other releasable holding means normally preventing folding of the boom, and a cable system including a cable leading from each drum of the winch, one cable leading from the winch at an upward and rearward incline over a guide on the mast to engagement with the boom above its pivot, and the other cable leading from the winch to the mast in erecting relation thereto.

5. A crane as in claim 4 in which said one cable passes over and about a sheave on the boom, then extends forwardly over another guide on '20 means connected with the boom operable to sethe. mast, and thence is formed 'a's' 'a block and tackle unit which'extends at a forward and downward incline to connection with the body some distance ahead of the mast. Y

6. A-crane comprising a longitudinally extending wheel-supported body connected in draft relation with a tractor including an engine actuated winch, said winch having a pair of selectively controlled cable drums, a boom supporting mast normally upstanding from the rear end portion of the body, a brace pivotally connected to the mast intermediate its ends and extending at a forward and downward incline, a carriage supported on and adapted-to move'alongthe body ahead of the mast, the brace being pivotally connected at its lower end-to the carriage, "releasable means normally preventing movement of. the carriage, a cable leading from one drum of the winch rearwardly and about a sheave fixed on the body to therear of said carriage and thence extending forwardly toengagement with the latteiyand a separate cable leading from the other drum of the winch rearwardly and upwardly to engagement with the mast adjacent its upper end. i

'7. A crane comprising a longitudinally extending Wheel-supported body connected in draft relation with a tractor including anengine actuated winch,said winch having a pair of seleccarriage, a cable leading from one drum of the winch rearwardly and about a sheave fixed on the body to the rear of said carriage and thence extending forwardly to engagement with the latter, and a separate cable leading from the other drum of the winch rearwardly and upwardly to engagement with the mast adjacent its upper end; said first named cable passing about a sheave fixed on the carriage, then extending rearwardly and about another sheave fixed onthe body, and thence leading up to the mast, over a guide sheave, and out the boom to provide the lift cable of the crane.

8. A crane comprising a wheel-supported, selfpropelled vehicle including a power winch having a pair of separate cable drums, a mast normally upstanding from the vehicle some distance from the winch, the mast being pivotally mounted in connection with the vehicle for forward swing ing movement to a lowered position, a carriage winch, releasable holding means between the mast and boom normally preventing folding of the latter, and a separate cable leading from the other drum upwardly over a guide on the mast, about a direction changing sheave on the inner end portion of the boom above its pivotal axis,

'and thence being anchored in relation to the mast --to exert a lowering force thereon.

,l'EBJ end and being pivotally mounted thereon for forward swinging movement to a lowered position, the boom being foldable against the mast, swinging of the mast and folding of the boom,

releasable means normally preventing a pair of cables adapted to run from said drums,

vguide means for said cables on the body adjacent its forward end, one cable leading from said guide means to the mast in lowering relation thereto, and the other cable leading from said guide means to the mast in erecting relation thereto.

10. A crane comprising a longitudinally extending body having transversely spaced support ing wheels at its rear end and including a draft member at its front end, said member being adapted for connection with a tractor having a multiple drum power winch, a mast and boom assembly upstanding from the body adjacent its rear end and being pivotally mounted thereon for forward swinging movement to a lowered position, the boom being foldable against the mast, releasable means normally preventing swinging of the mast and folding of the boom, a pair of cables adapted to run from said drums,

' guide means for said cables on the body adjacent its forward end, one cable leading from said guide means to the mast in lowering relation thereto, and the other cable leading from said guide means to the mast in erecting relation thereto; said one cable being operative to control folding, and to eflect unfolding of, the boom when the mast is in said lowered position.

11. A crane comprising a longitudinally extending body with a power unit at one end thereof, which power unit includes a dual drum power winch, a mast pivotally mounted on the body in spaced relation to the power unit, a boom extending outwardly from said mast, cable means engaged with one drum of the winch and connected with the upper end of the mast and operable to pull the mast from vertical to inclined position, separate cable operated means associated with the mast to lift it from inclined to vertical position and such latter means including a cable operably connected with the other drum and extending thence through operable connection with said lifting'means, thence up and over the top of the mast and thence out to the outer end of the boom, a block and tackle element on the outer end of said cable forming the lift for the crane, and means for temporarily anchoring the latter element to said body and to then permit such second cable to be gradually paid out from the drum as the mast is being lowered through the medium of the other drum and cable, whereby to control the speed of lowering of the mast.

ROBERT G. LE TOURNEAU.

Images