US3368696A

US3368696A - Telescopic crane boom

Info

Publication number: US3368696A
Application number: US587053A
Authority: US
Inventors: Roger L Johnston; Kenneth O Freund
Original assignee: SARGENT ENGINEERING CORP
Current assignee: SARGENT ENGINEERING Corp
Priority date: 1966-10-17
Filing date: 1966-10-17
Publication date: 1968-02-13
Anticipated expiration: 1985-02-13
Also published as: GB1152143A

Description

Feb. 13, 1968 R. JOHNSTON ET L 3,368,696

TELESGOPIC CRANE BOOM Filed Oct. 17, 1966 5 Sheets-Sheet 1 I 'II 24 WWW!!! HIIIIIIHIIIIIIHHIIHH nulmuumnmmm Feb. 13, 1968 R. JOHNSTON ET AL 3,368,696

TELESCOPI C CRANE BOOM 5 Sheets-Sheet 5 Filed Oct. 1'7, 1966 5 e 0 m W N 5 E w Wm o mJa i m m 2 N 0 m k w m. 3 w v m Feb. 13,1968 RLJOHNSTON ETAL 3,368,696

TELESCOPIC CRANE BOOM //v vzwmps P065? 1. Joy/vs m/v Maw/714 Q fksu/vo ATTORNEY Feb. 13, 1968 JOHNSTON ET AL TELESCOPIC CRANE BOOM 5 Sheets-Sheet 5 Filed Oct. 1'7, 1966 .09} w w w mvwvn N y! 2 NM m 9 0% 7 N E MM u, 5

United States Patent 3,368,696 TELESCOPIC CRANE BOOM Roger L. Johnston and Kenneth 0. Freund, Fort Dodge, Iowa, assignors to Sargent Engineering Corporation, Fort Dodge, Iowa, a corporation of Iowa Filed Oct. 17, 1966, Ser. No. 587,053 6 Claims. (Cl. 21259) This invention relates generally to a multiple section hydraulically extendible boom structure for a crane or the like and in particular to a power-operated telescoping outermost or fly section for such a boom structure and the method for power extending and retracting the fly section.

In telescoping boom structures having lengths in the neighborhood of from eighty feet to one hundred feet and capable of handling loads of about forty tons it is desirable that the boom sections be of a required strength with a minimum of weight. It is further desirable that the boom sections be successively telescopically receivable one within another so as to reduce the over-all length of the boom for transport purposes to a length substantially equal to the length of the innermost .or base section of the boom.

In boom structures having the above requirements, and because of space and weight limitations, all of the boom sections except the outermost or fly section, are operatively associated with a linearly extendible power means, usually a hydraulic cylinder and piston assembly, providing for the extension and retraction of a section relative to a next adjacent inner section. When the fly section is to be used it is now the usual practice, and while the boom is retracted and in a lowered horizontal position to manually, directly or through mechanical means, extend the fly section from the next adjacent section and then connect such two sections against relative longitudinal movement. In use, therefore, the fly or outermost section functions as a fixed forward extension for the next adjacent inner section. After use and with the boom retracted and in a lowered horizontal position the fly section is mannually returned to a retracted position within the next adjacent boom section.

An object of this invention is to provide an improved multi-section hydraulic extensible boom for a crane or the like.

Another object of this invention is to provide an improved method for extending and retracting the fly section of a multi-section hydraulically extendible boom structure.

A further object of this invention is to provide a telescopic boom wherein the fly section is power-operated to extended and retracted positions therefor.

Stiil a further object of this invention is to provide a telescopic boom having an inner section, a mid-section and an outer or fly section wherein the power means for extending and retracting the mid-section relative to the inner section is also utilized to extend and retract the fly section relative to the mid-section.

Another object of this invention is to provide a telescopic boom having an inner section, a mid-section and a fly section wherein a linearly extendible power means positioned within the fly section, when all three sections are telescopically retracted, has one end connected to the inner end of the inner section. The opposite end of the power means is connected to a coupling member slidably mounted for longitudinal movement within the fly section for detachable connection with the outer end of the fly section to provide for the power means retracting and extending the fly section relative to the mid-section, and for detachable connection to the inner end of the fly section and to the outer end of the mid-section to provide for the power means retracting and extending the mid- 3,368,695 Patented Feb. 13, 1968 section relative to the inner section with the fly section extended from the mid-section.

Further objects, features and advantages of this invention will become apparent from the following description when taken in connection with the accompanying drawings wherein:

FIG. 1 is a perspective view of a mobile crane incorporating the boom structure of this invention and wherein the boom is illustrated in retaracted transport position;

FIG. 2 is a reduced perspective view of the mobile crane in FIG. 1 showing the boom structure in extended operating position;

FIG. 3 is an enlarged foreshortened longitudinal sectional view of the boom structure with the sections thereof in retracted positions;

FIG. 4 is a transverse sectional view taken on the line 44 in FIG. 3;

FIG. 5 is an enlarged transverse sectional view as seen on the line 55 in FIG. 3;

FIG. 6 is a horizontal longitudinal sectional view of the outer end of the boom structure showing the fly section connected for retraction and extension relative to a next adjacent inner section;

FIG. 7 is illustrated similarly to FIG 6 and shows the fly section connected to and extended from the next adjacent inner section for movement therewith;

FIG. 8 is a vertical longitudinal sectional view of the outer end of the boom showing the fly section connector for movement relative to the next adjacent inner section;

FIG. 9 is illustrated similarly to FIG. 8 and shows the fly section connected to and extended from the next adjacent inner section for movement therewith;

FIG. 10 is illustrated similarly to FIG. 8 and shows the relative arrangement of those parts of the boom structure providing for a retraction of the outermost or fly section; and

FIG. 11 is a perspective view of a coupling member forming part of the structure providing for the power operation of the fly section to extended and retracted positions therefor.

Referring to the drawings there is illustrated in FIGS. 1 and 2 a crane vehicle 15 which includes the boom structure 16 of this invention. Mounted on the frame 17 of the vehicle 15 are hydraulically operated Outriggers 18. When the crane is to be operated the Outriggers 18 are adjustable laterally outwardly of the vehicle frame 17 and then extended into engagement with the ground to remove a part of the load from the vehicle frame 17 so as to cooperate with the vehicle wheels 19 in stabilizing the vehicle frame 17 against lateral and vertical HIOVCITKEUIS.

A turntable 21 carried at the rear end of the vehicle frame 17 rotatably supports a base frame 22 for 360 horizontal rotation relative to the vehicle frame 17. The boom structure 16 is pivotally mounted on the base frame 22 for pivotal up and down movement by a pair of hydraulic cylinder assemblies 23 shown best in FIG. 2. Also mounted on the base frame 22 is an operators cab 24- and a power plant, indicated generally at 26, for rotating the base frame 22, for operating oil pumps (not shown) to supply oil under pressure to a hydraulic motor 27 forming part of a winch unit 28 that is supported on the rear end of the boom structure 16, and to a hydraulic motor (not shown) for supplying oil under pressure to hydraulic cylinder assemblies, to be later described, for extending and retracting the boom structure 16.

In transport, and as shown in FIG. 1, the retracted boom structure 16 is extended horizontally and longitudinally of the vehicle frame 17. A drivers cab 29 and a power unit 31 for driving the vehicle 15 are mounted at the front end of the vehicle frame 17 below and in a clearance relation With the boom structure 16. To counteract the overhanging weight of the boom structure the base frame 22 is provided with a counterbalance 32.

Referring to FIGS. 2 and 3 the boom structure 16 is shown as comprised of four tubular sections, namely, a base or inner most section 33 of a rectangular shape in transverse section, and an outermost or fly section 34 and

intermediate sections

36 and 37 of substantially square shapes in transverse section. The

sections

36 and 37 will hereinafter be referred to as a first inner section and a second inner section, respectively. As shown in FIGS. 1 and 3 the boom sections, from the fly section 34 inwardly, are successively telescopically received one within another so that the boom structure 16, when retracted, has a length which is a little longer than the length of the base section 33.

The base section 33 is of a size in transverse cross section to receive therein the first inner boom section 36 and a lineally extendible power means 38, illustrated as a hydraulic cylinder assembly, having a cylinder 39 and a piston rod 41. The cylinder assembly 38 is extended longitudinally of the base section 33 at a position above the first inner section 36-. The closed or rear end of the cylinder 39 is pivotally connected at 42 to the rear or inner end of the base section 33 with the free end of the piston rod 41 pivotally connected at 43 to the outer or forward end of the top wall 45 of the first inner section 36.

A second lineally extendible power means 44, also illlustrated as a hydraulic cylinder assembly, and including a cylinder 46 and a piston rod 47 is located interiorly of the fiy section 34, when the fly section is retracted within the second inner boom section 37. The closed or rear end of the cylinder 46 is pivoted at 48 to the rear end of the first inner section 36 with the free end of the piston rod 47 pivotally connected by a pin 49 to the rear end of an elongated coupling member 51 located within and slidable longitudinally of the fly section 34 for a purpose to appear later.

To provide for a free guided relative longitudinal movement between the adjacent sections of the boom structure 16 the first inner section 36 on its top side 45 and adjacent the rear end thereof carries a pair of transversely opposite pivotally supported bearing plates 53 arranged to opposite sides of the cylinder assembly 38 and adapted for contact engagement with the underside of the top wall 54 of the base section 36. Secured to the forward or outer end of the bottom wall 56 of the base section 33 is a bearing plate 57 for contact engagement with the underside of the bottom wall 58 of the first inner section 37. Vertical clearance between the

inner sections

36 and 37 is maintained by a bearing plate 59 secured to the rear end of the top Wall 61 of the second inner section 37 for contact engagement with the underside of the top wall 45 of the first inner section 36. A bearing plate 62 mounted at the front end of the bottom wall 63 of the first inner section 36 is adapted for contact engagement with one underside of the bottom wall 64 of the second inner section 37. The fly section 34 has a bearing plate 66 adjacent the rear end of its top wall 67 for contact engagement with the underside of the top wall 61 of the second inner section 37. A bearing plate 68 at the front end of the bottom wall 64 of the second inner section 37 is adapted for contact engagement with the bottom wall 69 of the fly section 34.

To provide lateral clearance between the boom sections during relative longitudinal movement therebetween each of the

side walls

71, 72, and 73 of the

sections

36, 37 and 34, respectively (FIG. 4), has adjacent its rear end a bearing plate 74 extended laterally outwardly therefrom for contact engagement with the inner surface of a next adjacent side wall of a boom section.

A load lifting cable 78 from the winch unit 28 (FIG. 1) is extended through the base section 33 (FIG. 3) at a position above the cylinder assembly 38 for travel over

pulleys

79 and 81 mounted at the outer ends of the

top walls

45 and 61 of the

inner sections

36 and 37, respectively. From the pulley 81 the cable 78 is trained over

pulleys

82 and 83 supported on a block unit 84 secured to and projected forwardly from the outer end of the fly sections 34. The terminal end of the cable 78 carries a usual crane hook 85.

The coupling member 51 (FIGS. 10' and 11) includes a pair of like upright side plates 84. The opposite ends of each plate 84 terminate in apex or triangular sections 86 and 87. For convenience the end sections 86 and 87 of a plate 84 will be referred to as the front and rear end sections, respectively, of the coupling member 51. The plates 84 are connected together intermediate their upper and lower edges by a horizontal longitudinally extended plate member 88. Spaced longitudinally of the upper and lower edges of the plates 84 and secured thereto are transversely extended bearing members 89 adapted for contact engagement with the inner surfaces of the top wall 67 and bottom wall 69 of the fly section 34. Extended laterally outwardly from each side plate 84 are longitudinally spaced bearing blocks 91 for contact engagement with the inner surfaces of the side walls 73 of the fly section 34. The coupling member 51 is thus guidably supported for slidable movement longitudinally of the fiy section 34.

The pin 49 which pivotally connects the free end of the piston rod 47 of the cylinder assembly 44 to the coupling member 51 is extended between and rotatably supported on the rear apex sections 87 of the side plates '84. The apices of the front apex sections 87 of the side plates 84 are formed with transversely aligned openings 92. Rear wardly of the openings 92 the side plates 84 are formed with transversely aligned oval shaped openings 93 (only one of which is shown) for receiving the opposite ends of a transversely extended tubular member 94 which is of an oval shape in transverse section corresponding to the oval shape of the openings 93. The tubular member 914 is secured along its rear edge, as by welding, to the front edge of the connecting plate 88 and has the end surfaces thereof flush with the outer surfaces of the side plates 84.

The coupling member 51 constitutes a forward extension of the cylinder assembly 44 and provides for the assembly 44 being utilized as a common power means for extending and retracting the fly section 34 relative to the second inner section 37 and for extending and retracting the second inner section 37 relative to the first inner section 36 when the fly section 34 is connected to and extended from the second inner section 37.

In the operation of the boom structure 16 assume the sections thereof to be in their relatively retracted positions as indicated in FIG. 8 for the front end portions thereof. This retraction of the boom during road travel of the vehicle 15 is maintained, in conjunction with the retracted cylinder assemblies 38 and 44, by an eye pin 96 inserted through openings 97 and 98 provided at the forward ends of the

top walls

45 and 61 of the

inner sections

36 and 37, respectively. The fly section 34 is connected to the coupling member 51 by a pull-out pin 99 extended through openings 101 (FIG. 6) formed in the side walls 73 of the fly section and the openings 92 at the front ends 86 of the coupling member side plates 84.

When the boom structure 16 is to be used it is desirable that the fly section 34 be initially extended from the second inner section 37. With the boom structure 16 retracted and extended horizontally this is accomplished by extending the cylinder assembly 44 to its full length. Such initial extension of the cylinder assembly 38 moves the fly section 34 and attached coupling member 51 from their full line positions shown in FIG. 8 to their dotted line positions shown in the same figure. During this extension of the fly section 34 outwardly from the second inner section 37 the eye pin 96 is retained in place to prevent any forward movement of the second inner section 37. After the fly section 34 has been extended the pin 99 is withdrawn and the cylinder assembly 44 retracted whereby the coupling member 51 is pulled inwardly of the fly section 34 from its dotted line position shown in FIG. 9'to its full line position shown in the same figure. In this full line position the coupling member 51 has the tube 94 at the front end thereof in axial registration with transversely opposite holes 103 (FIG. 7) formed in the forward ends of the side walls 72 of the second inner section 37- and holes 104 at the rear ends of the side walls 73 of the fly section 34. A connecting pin 105 (FIG. 9) is then inserted through the aligned

openings

103 and 104 and the tube 94 to conmeet the coupling member 51 with both of the

sections

34 and 37. The eye pin 96 is then removed from the

inner sections

36 and 37.

The boom structure 16 may then be pivotally raised and lowered with later actuation of the cylinder assembly 44 providing for the extension of the second inner section 37 relative to the first inner section 36, with the fly section constituting a fixed forward extension for the second inner section 37. On actuation of the cylinder assembly 38 the first inner section 36 is extended from the base section 33 with the sections 37 and the fly section 34 being movable therewith as a unit.

When the boom structure 16 is to be retracted for transport purposes the first inner section 36 is retracted within the base section 33 and the second inner section 37 within the first inner section 36. The boom'is then lowered to a horizontally extended position, and the pin 105 withdrawn so that on extension of the cylinder assembly 44 the coupling member 51 is moved from its full line position in FIG. 9 to its dotted line position shown in the same figure. At this moved position of the coupling member 51 the front ends 86 of the plates 84 are in abutting engagement with a stop member 102 located adjacent the front end of the fly section 34 and secured to and extended between its side walls 73. This engagement between the coupling member 51 and the stop member 102 aligns the openings 101 in the fly section 34 with the openings 92 in the coupling member. The pull-out pin 99 is then inserted within such aligned openings and the cylinder assembly 44 is retracted to in turn retract the fly section 34 within the second inner section 37. The retracted position of the second inner section 37 within the first inner section 36, is limited by a stop member 106 provided adjacent the rear end of the first inner section 36 for abutting engagement with the rear end of the second inner section 37. This engagement aligns the openings 97 and 98 in the

sections

36 and 37, respectively, to receive the eye pin 96 for holding these two sections against relative longitudinal movement.

It is seen therefore thatthe invention provides for a hydraulically extendible boom structure 16 wherein the

boom sections

34, 36 and 37 are retractable and extendible by power means and wherein the cylinder assembly 44 is selectively connectible through the coupling mem ber 51 and pins 99 and 105 to the fly section 34 alone, or to the

sections

37 and 34 when the fly section 34 is projected from the second inner section 37.

The alignment of the

openings

103 and 104 in the

sections

37 and 34, respectively, with the tube 94 to receive the pin 105, following the extension of the fly section 34 from the section 37 is facilitated by the connection of the two

inner sections

36 and 37 by the eye pin 96. It is also to be noted that the insertion of the pin 105, to connect the

sections

34 and 37 with the coupling member is facilitated by the oval shape of the tube 94.

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 can be made therein which are within the full intended scope of this invention as defined by the appended claims.

We claim:

1. A telescopic hydraulically extensible boom for a crane or the like having at least three sections comprising:

(a) a first section,

(b) a second section telescopically received in the first section,

(c) a fly section telescopically received in the second section,

(d) a linearly extendible power means positioned interiorly of said fly section, when the fly section is telescoped within said second section, and connected at one end to the inner end of said first section, and

(e) means for detachably connecting the opposite end of said power means either to the outer end of said fly section or to the inner end of said fly section and the outer end of said second section.

2. A telescopic boom for a crane or the like having at least three sections comprising:

(a) an inner section,

(b) a mid-section,

(c) an outer section,

(d) said mid-section telescopically received within said inner section and said outer section telescopically received within said mid-section,

(e) a linearly extended power means positioned interiorly of said outer section with one end projected through the inner end of the mid-section for connection to the inner end of the inner section, and

(f) coupling means connected to the opposite end of said power means movable longitudinally of and within said outer section connectable either to said outer section alone or to both said outer section and mid-section, when the outer section is extended from said mid-section,

(g) said outer section, when connected alone to said coupling means, being linearly movable to extended and retracted positions relative to said mid-section by said power means and, when connected to said mid-section by said coupling means being movable with said mid-section relative to said inner section by said power means.

3. A telescopic boom for a crane or the like having at least three sections comprising:

(a) an inner section,

(b) a mid-section telescopically received within said inner section,

((1) an outer section telescopically received within said mid-section,

(d) a linearly extendible power means positioned longitudinally of and within said outer section with one end connected to the inner end of said inner section,

(e) a coupling member slidably mounted for longitudinal movement Within said outer section and connected to the other end of said power means, and

(f) means for detachably connecting said coupling member to the outer end of said outer section to provide for the extension and retraction of said outer section relative to said mid-section by said power means, or to the inner end of said outer section and to the outer end of said mid-section to provide for said mid-section and outer section being moved together by said power means relative to said inner section.

4. A telescopic boom for a crane or the like having at least three sections comprising:

(a) a tubular inner section,

(b) a tubular mid-section telescopically received within said inner section,

(c) a tubular outer section telescopically received within said mid-section,

(d) a linearly extendible and retractable hydraulic cylinder assembly extended longitudinally within said outer section with one end projected therefrom and connected to the inner end of said inner section,

(e) an elongated coupling member slidably mounted within the outer section and connectable to the opposite end of said hydraulic assembly,

(f) a first means for detachably connecting said coupling member only to said outer section for extension and retraction of said outer section relative to said mid-section in response to extension and retraction of said hydraulic assembly, and

(g) a second means, when said first connecting means is disconnected and said outer section is extended from said mid-section, for connecting said mid-section and outer section to said coupling member for movement together relative to said inner section in response to extension and retraction of said hydraulic assembly.

5. The telescopic boom according to claim 4 wherein:

(a) said mid-sectionis formed with a pair of transversely opposite aligned openings adjacent the front end thereof, said outer section is formed with a pair of transversely opposite aligned openings adjacent each end thereof, and said coupling member at the end thereof remote from said hydraulic cylinder assembly having a pair of longitudinally spaced transversely extended openings,

(b) said first connecting means comprising pin means insertable within the openings at the outer end of said outer section and one of the openings in said coupling member, when said outer section is retracted within said mid-section, and

(c) said second connecting means comprising pin means insertable within the other opening in said coupling member, the openings in said mid-section and the openings adjacent the inner end of said outer section, when the outer section is extended from said mid-section.

6. The method for extending and retracting the fly section of a telescopic boom having at least three sections wherein the fly section is telescopically received in a midsection and the mid-section is telescopically received in an inner section comprising:

(a) arranging a linearly extendible power means within the flysection with one end connected to the inner end of the inner section and an opposite end detachably connectable with the outer end of the fly section when the fly section is telescoped within the mid-section,

(b extending the power means to extend the fly section from the mid-section, and disconnecting the opposite end of the power means from the outer section,

(0) retracting the power means and detachably connecting the opposite end thereof to the outer end of the mid-section and to the inner end of the fly section so that subsequent retraction and extension of the power means will extend and retract the mid section relative to the inner section with the fly section constituting a forward extension of said midsection,

((1) retracting the mid-section relative to the inner section and disconnecting the opposite end of the power means from the outer end of the mid-section and the inner end of the fly section,

(e) extending the power means relative to the mid-section and fly section to position the opposite end of the power means at the outer end of the fly section, and

(t) then detachably connecting the opposite end of the power means to the outer end of the fly section and retracting the power means to telescope the fly section within the mid-section.

References Cited UNITED STATES PATENTS 2,571,858 10/1951 Garland 212 2,668,625 2/1954 Garland 21255 3,300,060 1/1967 Lado 21255 ANDRES H. NIELSEN, Primary Examiner.

Claims

1. A TELESCOPIC HYDRAULICALLY EXTENSIBLE BOOM FOR A CRANE OR THE LIKE HAVING AT LEAST THREE SECTIONS COMPRISING: (A) A FIRST SECTION, (B) A SECOND SECTION TELESCOPICALLY RECEIVED IN THE FIRST SECTION, (C) A LINEARLY EXTENDIBLE POWER MEANS POSITIONED INSECTION, (D) A LINEARLY EXTENDIBLE POWER MEANS POSITIONED INTERIORLY OF SAID FLY SECTION, WHEN THE FLY SECTION IS TELESCOPED WITHIN SAID SECOND SECTION, AND CONNECTED AT ONE END TO THE INNER END OF SAID FIRST SECTION, AND (E) MEANS FOR DETACHABLY CONNECTING THE OPPOSITE END OF SAID POWER MEANS EITHER TO THE OUTER END OF SAID FLY SECTION OR TO THE INNER END OF SAID FLY SECTION AND THE OUTER END OF SAID SECOND SECTION.