US3695467A

US3695467A - Boom assembly for a crane

Info

Publication number: US3695467A
Application number: US72383A
Authority: US
Inventors: John L Grundon
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-09-15
Filing date: 1970-09-15
Publication date: 1972-10-03
Anticipated expiration: 1989-10-03

Abstract

The boom assembly has a boom member and a stock member of box constructions with the stick member pivoted to the boom member adjacent the top of an upright extension provided at the free or forward end of the boom member. The actuating cylinder for the stick member is located within the boom member, and the actuating cylinder for the boom member projects transversely therethrough adjacent its rear end for pivotal connection with the upper wall of the boom member.

Description

United States Patent Grundon [54] BOOM ASSEMBLY FOR A CRANE 51 Oct. 3, 1972 Primary Examiner-Gera.ld M. Forlenza Assistant Examiner-George F. Abraham [72] Inventor. John L. Grundon E. 16th &

Howard D12, Des Moines, Iowa Atmmey Rud]ph Lowell 50333 [57] ABSTRACT [22] Filed: Sept. 15, 1970 The boom assembly has a boom member and a stock I PP N05 72,333 member of box constructions with the stick member pivoted to the boom member adjacent the top of an 52 US. Cl. ..214/147 0, 214/147 AS upright extension provided at the free or forward end 51 Int. Cl ..B66c 1/47 of the boom member- The actuating cylinder for the [58] Field of Search ..214/147, 147 o, 147 AS stick member is located h n he m m m r, and the actuating cylinder for the boom member projects [56] References Cited transversely therethrough adjacent its rear end for pivotal connection with the upper wall of the boom UNITED STATES PATENTS member.

3,080,988 3/1963 Redman ..2l4/l47 G X 3,330,056 7/1967 Woodside ..2l4/l47 G X FOREIGN PATENTS OR APPLICATIONS 2 Claims, 7 Drawing Figures 1,027,453 4/1966 Great Britain ..2l4/ 147 G ilv l. T

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/2 U U H B PATENTEDom 3 1912 saw 1 UF 2 BOOM ASSEMBLY FOR A CRANE SUMMARY OF THE INVENTION The boom assembly of this invention is of a rigid box construction with the pivoted end of the stick member guidably received within the boom member. The pivoted support of the stick member at a position above the upper wall of the boom member provides for the location of the stick cylinder within the boom member and an actuation of the stick member by an effective movement arm equal to at least the distance between the longitudinal axis of the boom member and the pivotal connection of the stick member. The stick cylinder is thus effectively shielded by the boom member against any accidental contact engagement with a load suspended from the free end of the stick member.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of the rear portion of a truck showing a crane with the boom assembly of this invention in assembly relation therewith;

FIG. 2 is a top plan view of the boom member, with parts removed for the purpose of clarity, showing the assembly therewith of the hydraulic cylinder units for actuating the boom member and an associated stick member;

FIG. 3 is a longitudinal sectional view of the boom member as seen along the line 3 3 in FIG. 2;

FIG. 4 is a detail perspective view showing the connection of the boom member with its actuating hydraulic cylinder unit;

FIG. 5 is an enlarged sectional view taken along the line 5 Sin FIG. 2;

FIG. 6 is a diagrammatic illustration of the assembly shown in FIG. 1 showing a log being picked up from a ground supported position; and

FIG. 7 is illustrated similarly to FIG. 6 and shows the log in an elevated loading position.

DETAIL DESCRIPTION OF THE INVENTION Referring to FIG. 1 of the drawing, there is illustrated a truck 10 that includes a main frame 11 on which is rotatably supported in a usual manner a crane 12 having a base deck or platform 13. Pivotally mounted on the base deck 13 for up and down pivotal movement is the boom assembly 14 of this invention which includes a boom member 16 and an associated pivoted extension or stick member 17. The boom member 16 is actuated by a hydraulic cylinder unit 18 that has a cylinder 19 pivoted at one end to the base deck 13 and an associated piston rod 21 pivotally connected to the boom member 16. The stick member 17 is pivotally moved relative to the boom member 16 by a hydraulic cylinder unit 22. A hydraulically operated grapple hook 23 for engaging and lifting a log 24 is pendantly supported from the free end 26 of the stick member 17. A heeler 27 rigidly secured to the stick member 17 and projected downwardly therefrom coacts with the grapple hook 23 to hold an engaged log in a horizontally extended position.

The boom member 16 (FIGS. 2 and 3) is of a welded box construction comprised of a pair of transversely opposite upright longitudinally extended side members 28 of a channel shape having upper and

lower legs

29 and 31, respectively, which project inwardly toward each other. The upper legs 29 are connected together by a rear plate member 32 and a central plate 33. In like manner the lower channel legs 31 are connected together by a rear plate member 34 and a central plate member 36. Secured to the forward sections 37 of the side members 28 and forming extensions thereon projected upwardly from the upper channel legs 29 are triangular shaped plate members 38 that are connectedtogether by a front connecting plate 39. Spaced longitudinally of the side channel members 28 and extended transversely thereof between the upper and

lower leg sections

29 and 31, respectively, are upright connecting plates which include what will be referred to as a front mounting plate 42 and a rear mounting plate 43.

It is seen, therefore, that the boom member 16 (FIG. 3) has the bottom side thereof open between the

lower plate members

34 and 36 and forwardly of the central plate member 36 at a position below the extension plates 38. The top side of the boom member 16 (FIG. 2) is open at opposite ends of the upper central plate member 33. I

Secured to the rear mounting plate 43 (FIGS. 2 and 3) is a pair of rearwardly projected pivot connectors 44 which form part of a pivot connection that pivotally supports the boom member 16 on the base deck 13 of the crane assembly 12. Adjacent the upper end of each extension plate 38 is a transversely extended bearing member 46. These bearing members 46 are in alignment transversely of the boom member 16 to receive a pivot pin 47 for pivotally connecting the rear end of the stick member 17 to the forward end of the boom member 16. It is to be noted that the stick member 17 is pivotally swingable between the extension plates 38 and forward sections 37 of the side channel members 28. i

The hydraulic cylinder unit 22 for actuating the stick member 17 is located between and extended longitudinally of the channel side members 28 with its cylinder 48 in an overlying relation with the front portion of the lower central plate 36. The rear end of the cylinder 22 is pivotally connected to the boom member 16 by means including a pivot pin 49 extended transversely of the boom member and rotatably supported in bearings 51 (FIGS. 2 and 5) carried in the side members 28 and in a pair of supporting plates 52 that are secured to and project forwardly from the front mounting plate 42. As shown in FIGS. 2 and 3, the longitudinal axis of the cylinder unit 22 and boom member 16 are substantially coincident.

The piston rod 21 of the cylinder unit 18 (FIG. 4) extends transversely of the boom member 16 through the opening formed between the lower connecting

plate members

34 and 36, and between the side members 28 for projection through an opening 40 formed in the upper central connecting plate 33. The free end of the rod 21 is received between a pair of transversely spaced bearing members 45, carried on the plate 33, for pivotal connection therewith by a 'pivot pin 50.

The stick member 17 is of a box. construction and has a pair of ears or lugs 53 (FIG. 1) projected outwardly from its rear side 54 for pivotal connection at 56 with the free end of a piston rod 57 that is operatively associated with the cylinder 48. It will be noted that the axis for the pivot 56 lies substantially in a horizontal plane common to the longitudinal axis of the hydraulic cylinder 22 so as to provide an effective moment arm for actuating the stick member 17 equal substantially to the distance between the axes of the pivot 47 and the hydraulic cylinder unit 22 when the stick member 17 is normal to the boom member 16 as illustrated in FIG. 6.

With the boom assembly 14 relatively arranged to provide for the grapple hook 23 picking up a ground supported log 24 (FIG. 6) the hydraulic cylinder unit 22 is located entirely within the confines of the boom member 16. The forward or free end section of the boom member 16 thus functions as a housing for the cylinder unit 22. On elevation of the boom assembly 14, concurrently with a movement the stick member 17 forwardly from the boom member 16, as shown'in FIG. 7 the rear end 58 of the log 24 is engaged by the heeler 27 to provide for the log 24 being horizontally extended in an elevated position to facilitate unloading thereof onto a truck or the like (not shown). As is wellknown, this heeling action takes place by virtue of that portion of the log 24 located ahead of the grapple hook 23 being of a longer length and therefor of greater weight than the rear portion 58 of the log.

in the loading of the log, it is seen that the rear edge 59 of the log 24 is closely adjacent to the underside of the boom member 16 so that during the manipulation of the log 24 for loading purposes the log end 59 is often moved into striking engagement with the underside of the boom member 16. This is due to the fact that the operators attention is directed primarily to the relative positions of the log 24 and the loading truck. Where the cylinder unit for a stick member is located outwardly from its associated boom member, such cylinder unit on being struck by a log is many times damaged beyond repair or has its service life appreciably shortened.

By virtue of the boom assembly of this invention, the cylinder unit 22, even when the rod 57 is partially extended forwardly from the front end of the boom member 16 is completely protected against being struck by a log 24 by virtue of its location between and within the vertical confines of the channel side members 28. This guarding action is accomplished while maintaining an efficient actuation of the stick member 17 by its associated cylinder unit 22 due to the pivot support of the stick member at 47 adjacent the upper ends of the upright extensions 38.

Although the invention has been described with respect to a preferred embodiment thereof, it is to be understood that it is not to be so limited since changes and modifications can be made therein which are within the full intended scope of the invention as defined by the appended claims.

Iclaim:

l. A boom assembly for a long handling crane having a self-propelled frame and a turntable rotatably mounted on said frame comprising:

a. a pivoted boom member of a box construction including a pair of transversely spaced side members joined by top and bottom members, said boom member being constructed with a forward section open at the top and bottom sides thereof and a rear section,

b. a pair of bearing supports pro ecting upwardly as an extension of said side members adjacent the front end of said forward section,

c. means pivotally supporting said rear section on said turntable for up and down pivotal movement of said forward section,

d. a stick member having one end positioned between and pivotally supported on said bearing supports at a first pivotal connection for pivotal movement betweensaid side members,

e. a first linearly extendible and retractible power unit for pivotally moving said stick member relative to said boom member extended longitudinally of and between said side members for extension and retraction relative to said front end of the forward section,

f. means pivotally connecting one end of said first power unit with said stick member at a second pivotal connection, means pivotally connecting the other end of said power unit with said side members at a third pivotal connection, said first, second, and third pivotal connections being positioned relative to one another and to the side members of the boom such that when the longitudinal axis of the stick member is normal to the longitudinal axis of said boom member with the stick member extending downwardly with respect to the boom member, the longitudinal axis of said power unit is located between the upper and lower sides of the side members of the boom member,

g. said first power unit being above the lower side of said boom member for all moved positions of said first power unit, whereby said power unit is protected from underneath by said side members,

h. a second linearly extendible and retractible power unit extended between and pivotally connected to said turntable and the rear section of said boom member, and

i. a power actuated log engaging unit movably suspended from the other end of said stick member.

2. The boom assembly for a log handling crane according to claim 1, wherein:

a. said stick member is movable in the open bottom side of said front section on movement rearwardly from the position thereof normal to said boom member.

Claims

1. A boom assembly for a long handling crane having a selfpropelled frame and a turntable rotatably mounted on said frame comprising: a. a pivoted boom member of a box construction including a pair of transversely spaced side members joined by top and bottom members, said boom member being constructed with a forward section open at the top and bottom sides thereof and a rear section, b. a pair of bearing supports projecting upwardly as an extension of said side members adjacent the front end of said forward section, c. means pivotally supporting said rear section on said turntable for up and down pivotal movement of said forward section, d. a stick member having one end positioned between and pivotally supported on said bearing supports at a first pivotal connection for pivotal movement between said side members, e. a first linearly extendible and retractible power unit for pivotally moving said stick member relative to said boom member extended longitudinally of and between said side members for extension and retraction relative to said front end of the forward section, f. means pivotally connecting one end of said first power unit with said stick member at a second pivotal connection, means pivotally connecting the other end of said power unit with said side members at a third pivotal connection, said first, second, and third pivotal connections being positioned relative to one another and to the side members of the boom such that when the longitudinal axis of the stick member is normal to the longitudinal axis of said boom member with the stick member extending downwardly with respect to the boom member, the longitudinal axis of said power unit is located between the upper and lower sides of the side members of the boom member, g. said first power unit being above the lower side of said boom member for all moved positions of said first power unit, whereby said power unit is protected from underneath by said side members, h. a second linearly extendible and retractible power unit extended between and pivotally connected to said turntable and the rear section of said boom member, and i. a power actuated log engaging unit movably suspended from the other end of said stick member.

2. The boom assembly for a log handling crane according to claim 1, wherein: a. said stick member is movable in the open bottom side of said front section on movement rearwardly from the position thereof normal to said boom member.