US1662902A - Shovel-crane boom - Google Patents

Description

L. A. RUSSELL SHOVEL CRANE BOOM March 20, 1928.

Filed July 2. 1924 I amounted, lflfimmcll GH -anew Patented Mar. 20, 1928.

UNITED STATES 1,662,902 PATENT OFFICE.

LESLIE A. BUSSELL,- OF MILWAUKEE, WISCONSIN, ASSIGNOR TO KOEHRING COMPANY,

OF MILWAUKEE, WISCONSIN, A CORPORATION,

SHOVEL-CRANE BOOM.

Application filed July 2,

This invention has relation to excavating machines of the type known commonly as shovel cranes or power shovels, wherein 1s employed a shovel boom and dipper means 8 mounted on said boom, andoperated from the.

power plant carried by the body of the crane.

The ordinary operation of cranes of the above type contemplates an excavating move ment of the dipper or shovel member usul ally involving elevating action thereof as 1t is crowded to its work, a lateral swinging or sweeping of the dipper and its handle bywhich is connectedwith'the boom, to bring the dipper into an unloading position over a vehicle or a place on which the contents .of the dipper may be dumped, and a subsequent restoration of the dipper by reverse operations to bring it back to its excavating position. Now it is well known in the art that with the usual types of supporting boom, dipper and dipper stick or handle constructions a rigid mounting of the boom upon the crane is usually provided. The dipper stick either straddles the supporting boom therefor, or passesbetween spaced parts of such boom in the usual constructions. The sad stick forms a long lever, and the operat ons of the crane usually are such that as the .car

or body of the crane turns to swing the boom and the dipper instrumentalities considerable momentum of these arts is created in their movement. The or 'nary operation of the machine furthermore, for efilciency, requlres rather sudden stop age of the boom IDOVB'.

ment in swin in t is being true both when the dipper is oa ed and when it is unloaded.

, Necessarily this action of the boom and dipper in the stopping movements creates severe stresses and strains both upon the l 40 boom supporting means at the point of connection w1th the crane body or car and upon the dipper stick or handleitself. At times the operator of themachine accidentally sideswipes a vehicle or bank or other obstacle, giving rise to additional severe stream on the connections at the foot of the boom and the di per stick of the dipper.

Ihe object of the present invention has been to produce, a comparatively simple dipper su porting boom construction, wherein the b0 y of the boom is mounted, practically speaking, for turning movement relatively-to the foot of the boom, about an axis longitudinally of the boom, the said body andfoot members of the boom being maintamed in 1924. Serial No. 723,623.

their normal positions by resilient means such as springs. These springs are designed to absorb the shocks and stresses to which the boom and dipper stick may be subjected inci dent to their use in ordinary excavating oper-' ations.

The foregoing resilient mounting of the boom, or its facility to turnabout a longitudinal axis, is advantageous for general mechanical operations, previously discussed, and is additionally advantageous from a.- manufacturing view-point because the construction of the supporting means for the boom'is not required to be so heavy and shock resistant as otherwise is the case, and furthermore this same thing applies to the construction of the dipper stick or handle as well.

In the accompanying drawings,

Figure 1 is adiagrammatic side view showing a shovel crane equipped with the constructional features embodying my invention.

Figure. 2 is a longitudinal sectional view of a somewhat fragmentary natureshowing absorbing shocks'incident to lateral stresses transmitted to the boom through the dipper means thereof. a v

Figure 3 is a side view showing substantially the same parts as are illustrated in Figure 2. 1

Describing my invention; specifically, I. designate the car or body of my crane at A in Figure 1, and the traction sup ort thereof at B, the latter being composed traction members, and there being provided the usual swing body or turntable mounting intermediate the car A and said traction support B. My shovel boom or boom element is designated at 1 and is supported by the foot 2. The dip 'er is desi ated at 3 and is connected to an supporte by the boom by the dipper stick 4. The dipper is hoisted by the hoisting cable 5, and suitable crowding out and racking in mechanism may be emof endless,

ployed of a more or less conventional nature so far as the invention hereof is concerned.

It will be observed that the dipper stick 4.

straddles the boom l-according to my particular construction illustrated, although this is not a necessary feature of the said COD:

struction because my iinvention is adapted to upon any suitable bracket means projecting from the car A of the crane. lhe outer portion of the .boom foot 2 is equipped with a longitudinal bearing, opening 7 in which is journaled the round journal end portion 8 of a boom casting 8, the opposite end of which is of square form and fits into the lower end of the body of the booml. Rivets or other suitable fastenings 9 may be employed to rigidly connect the boom casting 8, which is virtually a journal casting be--- cause it provides the journal member 8, with respect to the boom 1. At opposite sides of the boom 1 and .at its lower end adjacent to the square extremity. of the casting 8, are attached plates 10 b like, and these pl a downwardly off-standing arms or lugs 11. The lugs 11 are provided with apertures through which pass bolts or rods 12, which bolts also pass through spring casings or housings 13 that are preferably cast with the foot member 2 of the boom. The casings 13 enclose a. spring or springs of the expanding coil type designated at 14, and mounted in each casing 13 at its upper end is a plate 15 having a sleeve extension 16 that passes through the upper end of the casing and abuts with the under-side of the adjacent In 11. At its lower end the casing has a secon plate 17 which abuts with the lower ends of the springs, and is under-hung by an. abutment portion 2 on the foot member 2. 'A nut 18 is screwed upon the upper end of each bolt 12, and the head 19 of each bolt has an abutment relation with the under-side of the ad'acent plate 17.

n eflect, therefore, the boom 1 has radial projections 11, and the foot member 2 0 posed radial projections 13 with interme iately acting resilient devices.

It is to be noted that the casingsysprin and lugs or arms above set forth are norma y disposed in substantially vertical planes in opppsite sides of the boom 1 and its foot memr 2. Furthermore, normally the springs 14 by their expanding action hold the parts 15 and 17 at the opposite ends of the casin 13. But said springs when compressed a low fully rotary play of the booml in the foot member 2 b reason of the provision of the journal mem er 8'. In view of the foregoing features of construction it will be obvio'us that many shocks or stresses transmitted to the boom 1 andtcndin to twist the boom by torsional action, whic stresses and shocks are common todayin shovel cranes, will be absorbed by a yielding turning movemeans of rivets or the tes are equipped with,

ment of'the boom 1.on its member 2.

In other words, the boom 1 is capable of rotating relatively to the foot 2 and the said shocks or stresses are fully absorbed by the provision of the springs 14. It is notable,

too, that the springs 14 at opposite sides of vice-versa, whereby the springs at both sides" of the boom are'utilized in lending their re sistance to compression incident to-the absorption of the stresses involved in the rotative taming tendencies of the boom as transmitted thereto by the dipper stick in the constant swinging and stopping movements of the latter. 7

Having thus described my invention what I claim as new and desire to secure by Letters Patent is,

1. Ina crane of the class described, in

combination, a swing body, dipper shovel mechanism comprising a boom element, a dipper shovel mounted thereon, and a connection between the swing body and the said boom element comprising shock absorbing means maintaining the boom element in a certain normal relative position to the swing body but adapted to yield upon undue resistance to the movement of theshovel as 'it is swung with the swing body.

2. In a crane of the class described, in combination, a swing body, a shovel supporting boom element, a dipper shovel mounted thereon, means for racking in and crowding out the said dipper shovel, and an operative connection between the said boom element and the swing body comprising shock absorbing springs normally acting to hold the boom element in a certain position with its dipper shovel, in relation to the swing body, the said shock absorbing springs being adapted to yield and", 'ermit of relative movement of the boom e ement laterally in respect to the swing body when the dipper shovel meets with undue resistance as it is swung laterally with the boom element in working operations.

3. In a crane construction of the class described, in combination with the body of the crane, aboom construction includin a foot member connected with the body a oresaid, anda boom body member rotative about a upon the foot member, together with yielding means intermediate the boom body and foot members whereby to resiliently maintain them in normal operative sitions.

4. In a crane of the class escribed,

combination, a. crane body, a boom mounted I thereon, shovel means comprislng a' dipper and dipper stick connected to the boom, the said boom embodying resiliently connected longitudinal axis relatively to and mounted I mitted by the swing body.

- movements of the members ada ted for movement relatively to each other a out an axis longitudinally of the boom.

5. In a crane of the class described, in combination, a swing body, a shovel supporting boom element, a dipper shovel mounted upon said boom element, mechanism on the swing body for racking in and crowding outthe dipper shovel as it is carried by the boom element, and a mounting connection intermediate the boom element and the swing body and comprising cushion devices to absorb the shock incident to abnormal resistance to the lateral swing of the boom element when the dipper shovel meets with resistance the said cushion devices acting to absorb shocks set up by the undue stresses transthe shovel to the boom element and therefrom to the said connection with 6. As a new article of manufacture, a power shovel boom comprising a foot memher, -a' body member movably mounted upon the foot member, and resilient means intermediate the two for absorbing the shocks or stresses reated by sweeping and stopping boom under actual conditions of service. 4

7. A boom unit structure for shovel cranes comprising a foot member, a body member movably connected to the foot memher, and yielding devices intermediate the two comprising springs mounted upon one of said parts, lugs carried by the other of said parts cooperative with said springs, and connections between the lugs and springs substantially as described.

8. In combination a crane body, shovel boom apparatus carried thereby including a boom, a dipper stick and dipper carried by 'said dipper stick, the boom comprising a foot memberconnected with the crane and a body member and carrying the dipper stick movably mounted upon the foot member, together with resilientmeans intermediate the boom foot member and the boom body memher for absorbing shocks as an incident t relative movement of said parts.

9. A boom structure for power shovels comprising, a foot member, a body member rotatively mounted upon the foot member and resilient connecting means between the body member and the foot member located at opposite sides thereof, said resilient means including springs so connected with the foot and body members that. the sp'ring'means at one side of the boomcooperates to resist transmitted 'to the boom element,.

twisting or turning of the body of the boom in either direction.

10. A boom structure for power shovels comprising a foot member having spring casings'at opposite sides thereof, a body member having off-standing arms at opposite sides thereof terminating in line with the said casings, journalin'g means between the foot and body members including a journal casting having a square end portion fastened to the body member and the round journal end portion fitting into and rotatable on the foot member, together with springs and spring connecting parts carried by the casings and attached to the said arms of the foot member and body member substantially as set forth and described.

11. A revolving crane body, a boom assembly comprising a rockable boom foot pivoted to the said body for swinging in a verti-v cal plane and a boom arm longitudinally journalled in the boom foot, a dipper stick supported by the said arm, resilient means normally maintaining'the said stick and the said arm in planes, parallel with the crane bodys vertical center line while allowing the said arm and the dipper stick aforesaid to depart therefrom under stress in either lateral direction,

12. A shovel boom comprising a vertically rockable boom foot and a rotatable boom arm, resilient means oppositely positioned adjacent the said foot and said arm, op-

posed shoulder formationsupon the rockable boom foot and upon the rotatable boom arm to offer abutting 13. A shovel boom comprising two elements, at non-rotative foot member and a rotative arm, opposed radial projections outstanding from the said member and the said arm, resilient means aifecting the said projections to resist rotation of the saidarm,

flanges limiting a longitudinal bearing connecting the said foot and the arm aforesaid.

the said means located for responding to LESLIE A. RUSSELL;

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