US3249244A - Boom extension - Google Patents

Description

May 3, 1966 J, ELLERBROEK ET AL 3,249,244

BOOM EXTENSION 2 Sheets-Sheet 1 Filed Sept. 17. 1964 Tia.

INVENTOBS ELTON B. LONG J'oN JT ELLERBROEK Uzlson, Stflie & Crag Armenia 5 y 1966 J. J. ELLERBROEK ET AL 3,249,244

BOOM EXTENSION Filed Sept. 17, 1964 2 Sheets-Sheet 2 INVENTORS ELTON 5. LONG BY Jo- J. ELLERBROEK 0115011., Settle & Cray flrroRNEYJ United States Patent ration of Wisconsin Filed Sept. 17, 1964, Ser. No. 397,135 6 Claims. (CL 214-138) The present invention relates to tractor mounted digging apparatus and more specifically to a system, including method and apparatus, for inexpensively modifying the existing booms on tractor mounted backhoes and the like to increase the trenching depth capability thereof without significant alteration in the existing backhoe structure or in impairment of the structural integrity thereof.

In the recent past, the building codes of many cities and other jurisdictions have undergone ignificant changes and now require placement of water, sewage and like pipes at deeper locations beneath the ground surface. Some existing excavation equipment of the backhoe type lack the capability to trench to the new depths required. Consequently it has become advisable to modify this backhoe equipment so as to increase the depth of trenching capability sufficient to satisfy the new building code requirements.

One way of making such modifications to existing backhoe equipment is to re-tool at the factory and manufacture new component parts of extended length which may be used to replace the smaller existing components on the backhoe equipment. The cost of such an undertaking is usually prohibitive when balanced against the cost to the consumer. Consequently, to be economically feasible, the required increase in trenching capability must be achieved by some type of adaptation of the existing component parts of the equipment.

In the past, attempts to modify existing components of the existing backhoe trenching equipment have met with extremely limited commercial success because of extra weight, poor weight distribution, increased height of clearance during transportation from one job site to another, and like problems.

The present invention satisfactorily solves the foregoing problems and comprehends a novel, multi-positionable extension member designed to over-fit a tractor mounted backhoe boom and to pivotally connect to the dipper stick thereof. The extension member of this invention requires only limited reworking of the boom. No structural changes to the boom are required. The extension member may be installed upon the boom in a relatively brief period of time, with incurrence of only nominal costs. The extension may be rigidly fastened in any one of several positions along the boom and may be rigidly relocated from one position to another, as desired.

In accord with the foregoing, it is a primary object of the present invention to provide an extension member, mountable upon the distal end of a tractor mounted backhoe boom or the like, which may be selectively, rigidly positioned in any one of a plurality of positions along the boom, so that the trenching capability of the boom may be selectively extended or decreased.

The extension member of this invention may be embodied to have one or more of the following features:

(1) Good balance characteristics, i.e., a favorable center of gravity when installed in one of its several rigid positions between the backhoe boom and the dipper stick;

(2) Relatively light in weight;

(3) Low height clearance characteristics to accommodate easy transportation from one work site to another and thereby avoid interference with existing power lines and the like;

(4) Selectively positionable between extended and re- 3,249,244 Patented May 3, 1966 ice tracted positions to provide variable maximum depth of trenching capabilities;

(5) Lending itself to a handy method for installation of the extension member, requiring only a small amount of equipment downtime, limited manpower and no specialized equipment to physically install or remove the extension;

(6) Relatively low in cost so as not to be economically prohibitive to the ultimate consumer;

(7) Conveniently installable by non-technical persons, such as the purchasing consumer;

(8) Repositionable in any one of a plurality of rigid positions along the boom by one man, such as the operator of the machine, in a relatively short period of time without any requirement of additional power tools and the like; and

(9) Requiring only a minimum of rework to the backhoe boom and necessitating no major changes to the hydraulic equipment existing on the boom.

These and other objects and features of the present invention will become more fully apparent from the appended claims as the ensuing detailed description proceeds in conjunction with the accompanying drawings in which:

FIGURE 1 is a side elevation illustrating a presently preferred extension member as embodied by this invention in its installed working position. The horizontally illustrated backhoe apparatus of FIGURE 1 shown in dotted lines illustrates the extension member rigidly located in its retracted working position, while the vertical, illustrated backhoe apparatus shown in solid lines illustrates the extension member rigidly located in its extended working position;

FIGURE 2 is a side elevation solely of the extension member of FIGURE 1;

FIGURE 3 is a partial cross-section, taken along the lines 33 of FIGURE 1, illustrating the slide block assembly carried by the extension member in its installed position upon the boom;

FIGURE 4 is a rear elevation of the slide block assembly of FIGURE 3; and

FIGURE 5 is a partial side elevation of the backhoe boom of FIGURE 1, showing the limited alterations necessary to adapt it to receive the extension member of FIGURES 2, 3 and 4.

Referring now to the drawings, FIGURE 1 illustrates a presently preferred embodiment of the present invention in its installed position within the backhoe apparatus of a tractor mounted backhoe. From FIGURE 1, it is to be noted that the extension member maybe selectively posi tioned in (l) a retracted orientation upon the backhoe boom, as shown by the dotted-lined, substantially horizontally extending backhoe apparatus, and (2) in an extended position upon the backhoe boom, as illustrated by the solid-lined, substantially vertically extending backhoe apparatus of that figure.

It is to be remembered that the extension member, as embodied in FIGURE 1, is rigidly fixed in either the retracted or the extended position and does not move relative to the backhoe boom during digging or trenching operation. When the extension member is in the retracted position, its trenching pattern is such as is illustrated by the dotted line contained within the graph of FIGURE 1. When the backhoe apparatus is in its fixed, extended position, the digging pattern is as is illustrated by the solid line contained within the graph of FIGURE 1.

Specifically, backhoe apparatus 10 is mounted upon supports 14 and 16 at the rear of the tractor 12, which may be a track or rubber-tire tractor. These supports define a vertical axis about which backhoe apparatus 10 may pivot by actuation of proper hydraulic controls. Swing linkage support 18 is pivotally connected to tractor supports 14 and 16 and provides a horizontally extending pivot connection 20 about which a backhoe boom 22 may be hydraulically pivoted. This pivot action is responsive to energizing and deenergizing of boom cylinder assembly 24.

The piston rod of cylinder assembly 24 is pivotally fixed to boom 22 toward its distal end through the aperture 23 (see FIGURE and is pivotally anchored upon swing linkage support 18 at anchor 26. Backhoe boom 22 also carries anchor bracket 28 upon which anchor 30 is mounted. Anchor 30 normally carries the proximal end of the dipper stick cylinder assembly 40, i.e., when apparatus has not been modified by installation of the novel extension member of the present invention. Externally, telescopically mounted upon the distal end of boom 22 is shoe extension member 32 which is nonrotatably and non-movably held in the selected position during trenching. Extension member 32 is pivotably connected at pin connection 34 to the triangular support member 36 of dipper stick 38, and anchors the proximal end of the cylinder of the dipper stick cylinder assembly 40 by means of anchor plates 42. Plates 42 are rigidly held in the illustrated position with respect to extension member 32,,as, for example, by welding.

Dipper stick 38 pivotably anchors bucket cylinder assembly 44 at connection 46 of triangular support member 36. Cylinder assembly 44 is pivotably connected at its piston rod end to links 48 and 50'. Link 48, in turn, is pivotably attached to the dipper stick 38 and link 50 to bucket mounting bracket 52, which is integrally attached to bucket 54.

Hydraulic apparatus and control of cylinder assemblies 24, 40 and 44 as well as the hydraulic apparatus of swing linkage support 18 are conventional and form no part of the present invention. Hence, no further description of the hydraulics of backhoe apparatus is deemed necessary. The excavation or trenching procedure by use of backhoe 10 is the same as if extension member 32 were not present, with the exception of digging depth'capability. By inspection of FIGURE 1, it is apparent that the maximum I.E.M.C. (Industrial Equipment Manufacturers Council) digging depth of the illustrated backhoe apparatus is in excess of 14 feet, when the extension member is rigidly held in its retracted position and greater than 16 feet when the extension member is rigidly held in its extended position. These digging depths represent an improvement of on the order of one foot and two and one-half feet, respectively, for the retracted andextended positions of extension member 32.

The changes required in backhoe apparatus 10 incident to installation of extension member 32 are extremely nominal and have economic and utility advantages not present in any other known prior art apparatus for extending the trenching capability of an existing excavating equipment of the type described.

To illustrate the precise construction of extension member 32 and to illustrate modifications necessary to boom 22 and its correlation with extension member 32, in both the retracted and extended positions, reference is now made to FIGURES 2. through 5.

FIGURE 2 illustrates extension member 32 isolated from boom member 22 and dipper stick 38. Extension member 32 includes open-ended box 60 which takes the shape of the shoe, being open at the lefthand end 62 and capable of being fitted over the distal end of the boom 22. The box 60 is closed at its distal end 64 which defines the limit which extension member 32 may be retracted upon the boom 22 in the installed position. The box 60 may be formed, for example, from standard rolled steel shapes. As an illustration, a pair of standard rolled steel channel members may be fabricated and welded together to form open-ended box 60.

A support anchor pate 42 is mounted on each side of the box member 60 so as to be in transverse alignment with each other, for example, by welding. Plates 42 are pin connected by means of apertures 66 to anchor the cylinder end of the dipper cylinder assembly 40 when extension member 32 is in its installed working position. Each plate 42 also is provided with a lower aperture 68 (see FIGURE 3) through which slide block assembly 70 passes for movable surface support engagement with boom 22, as hereinafter to be explained.

Each slide block assembly 70 (see FIGURE 3) is bolt mounted to plate 42 and box 60 by means of bolts 72 and includes bearing plate 74 integrally connected, as for example, by Welding to concentric cylindrical pin 76.. The pin 76 is j-ournaled within a bushing 77 within a square slide plate 78 internal of the box 60 adjacent and in contiguous relation with the boom 22 (see FIG- URES 3 and 4). Each slide block assembly 70, at square plate 78, is supported by guide plates secured to the sides of the boom 22 in a manner and for a purpose which will be subsequently explained.

The box member 60 also contains aligned bossed apertures 80 on its respective sides for pin connection with the distal pin fitting of boom 22 when the extension 32 is positioned in its extended position, as shown in the vertically oriented embodiment of FIGURE 1.

An end casting 82 is rigidly fastened to the box member 60 at juncture 84 as, for example, by Welding. End casting 82 has a hollow recess 86 terminating at the end wall 64, and is provided with bossed aperture 88 which is pin attached to the distal aperture of boom 22 when extension member 32 is installed in its retracted position. End casting 82 also provides a bossed aperture 90' which, in the assembled position, is secured to connection 34 of pivot member 36 of the dipper stick 38. Abutment 92, also part of end casting 82, is used as a limit stop to prevent excessive counter clockwise rotation of pivot member 36, as viewed in FIGURE 1.

In order to adapt boom 22 to accept extension member 32 in over-fitting relation, guide plates 94 and 96 and stop plates 98 and 100 are fixed to each side of the boom 22, for example, by Welding. By inspection of FIGURE 5, it should be noted that guide plates 94 and 96 run substantially parallel to distal top surface 102 of the boom 22.

When the extension member 32 is installed upon the boom 22, as illustrated in FIGURE 3, the square side block 78 of each of the two slide block assemblies 70 is closely interposed intermediate guide plates 94 and 96 between stop plates 98 and 100. Accordingly, when slide blocks 78 are immediately adjacent stop plate 100, extension member 32 will be in its retracted position upon boom 22. In this retracted position, a pin assembly is securely fitted through bossed aperture 88 of the extension member 32an-d bossed terminal aperture 104 on the distal end of the boom 22 (see FIGURE 5) to thereby prevent relative movement of the extension member and boom with respect to each other during trenching operations with backhoe apparatus 10.

When the slide blocks 78 are positioned immediately adjacent their respective stop plates 98, extension member 32 is in its extended position with respect to boom 22. In the extended position, apin assembly extends through a bossed aperture .80 of extension member 32 and bossed aperture 104 on the distal end of the boom 22.

Hence, the two pins 76 are designed to be rotatable within bushing 77 to permit alignment of aperture 80 and aperture 104, .or aperture 90 and 104, as the case may be, without binding slide blocks 78 between guide plates 94 and 96.

With reference to FIGURE 1, backhoe apparatus 10, when extension member 32 has not been installed thereupon, has the cylinder end of cylinder assembly 40 anchored pivotably in connection 30. In this condition, the pin of connection 34 of pivot member 36 is also fitted through distal end of bossed aperture 104 of the boom 22 (FIGURE 5).

To modify and adapt the backhoe apparatus for reception of extension member 32 upon the boom 22, only limited inexpensive steps need be conducted. First, with the possible exception of repositioning of the hydraulic apparatus, such as hydraulic lines and fittings or like incidental equipment features used in conjunction with backhoe apparatus 10, the only structural change required is the welding or like placement of guide plates 94 and 96, and stop plates 98 and 100, upon each side of the boom. No additional changes are required.

To place extension 32 upon boom 22, the anchor of the cylinder of cylinder assembly 40 is detached from connection 30 and the pin assembly which pivotably connects aperture, 104 of boom 22 with connection 34, are disassembled. The shoe-shaped extension member 32 is then over-fitted upon the distal end of the boom 22 with slide block assemblies 70 positioned so as to cause slide blocks 78 to be intermediate slide plates 94 and 96. This can be done by placing slide blocks 78 along with bushings 77 intermediate guide plates 94 and 96, by placing extension member 32, absent pin 76, plate 74 and bolt 72 upon boom 22, and thereafter inserting pin 76 into bushings 77 and securing bolts 72 within their respective threaded apertures in the plate 42 and the box member 60. If it is desired to have extension member 32 in its retracted position upon the boom 22, then slide blocks 78 are positioned immediately adjacent stop plates 100and a pin assembly is inserted through apertures 88 and 104 of extension member 32 and boom 22, respectively. If it is desired to position extension member 32 in its extended position upon boom 22, then slide blocks 78 are positioned adjacent their respective stop plates 98 and the pin assembly is positioned through apertures 80 and 104 of extension member 32 and boom 22, respectively. Thereafter, the cylinder end of cylinder assembly 24 is anchored to anchor plates 42 of extension member 32 by means of a pin connection through apertures 66. A pin assembly is fitted through pivot connection 34 of pivot member 36 and through aperture 90 of extension member 32 to complete reattachment of dipper stick 38 to backhoe apparatus 10.

T o reposition extension member 32 from its extended to its retracted position, the pin assembly interconnecting apertures 80 and 104 of extension member 32 and boom 22, respectively, is removed. Boom cylinder assembly 24 is actuated to raise the boom, causing extension member 32, by the force of gravity, to move away from the distal end of boom 22 until slide blocks 78 come to rest adjacent stop plates 100. Guide plates 94 and 96 are oriented parallel to top surface 102 of the distal end of boom 22, so that slide blocks 78 move parallel to surface 102. This aligned parallel movement automatically causes aperture 88 of extension member 32 to align with aperture 104 of boom 22, so that the pin assembly may be inserted therethrough when extension member 32 has reached its full retracted position. The retracted position is the preferred position When backhoe 10 and tractor 12 are being transported from one job site to another, since interference with power lines and the like is avoided.

To reposition extension member 32 from its retracted position to its extended position, the pin assembly is removed from apertures 88 and 104. Backhoe bucket 54 is placed upon the ground and dipper cylinder assembly 40 is actuated, causing extension member 32 to move forwardly along boom 22 until slide blocks 78 are adjacent stop plates 98. At this point, aperture 80 of extension member 32 will be aligned with aperture 104 of boom 22, and a pin assembly may be inserted therethrough following which backhoe apparatus 10 is again ready for trenching service.

Extension member 32 may be repositioned (by one man) from the retracted position to the extended position (or vice versa) with respect to the illustrated embodiment, in less than five minutes.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. In a tractor mounted backhoe apparatus having a boom and a dipper stick pivotably connectable with said boom, the improvement comprising extension means solely interconnecting said boom and said dipper stick, said extension means over-fitting the distal end of said boom and being pivotably attached to said dipper stick, said extension means having means movably attached to said boom in at least one location and means fixedly locatable in at least one of a plurality of selectable locations.

2. In a tractor mounted backhoe having a boom normally carrying a dipper stick pivotally mounted at one end thereof and having an actuating cylinder anchored to said boom and a piston rod pivoted to said dipper stick, the improvements of a boom extension element of hollow box-like configuration telescopically slidable over said boom, interengaging slide means on said boom, said extension accommodating relative telescopic boom-extension movement, an anchor bracket on said extension to which said cylinder is attachable, said extension having a pair of spaced apertures selectively registrable with said one end of said boom, and means selectively insertable through said extension apertures and into said one end of said boom to secure said extension and said boom into assembly in a pair of relatively telescoped positions.

3. In a tractor mounted backhoe having a boom normally carrying a dipper stick pivotally mounted at one end thereof and having an actuating cylinder anchored to said boom and a piston rod pivoted to said dipper stick, the improvements of a one-piece, integral boom extension element of hollow box-like configuration telescopically slidable over said boom having slidable attachment means interengaging slide means on opposite sides of said boom, said extension accommodating relative telescopic boomextension movement, an anchor bracket on said extension to which said cylinder is attachable, said extension having a pair of spaced apertures selectively registrable with said one end of said boom, and a pin assembly selectively insertable through either of said extension apertures and into said one end of said boom to secure said extension and said boom into assembly in either of a pair of relatively telescoped positions.

4. In a tractor mounted, hydraulically controlled trenching apparatus having a vertically hinged tractor-support, a boom horizontally journaled on said support and having a journal member at the free end thereof, a dipper stick assembly normally pivotably secured to said journal member of said boom, a bucket pivotally connected to said dipper stick, and a hydraulic cylinder and rod assembly for pivoting said dipper stick assembly with respect to said journal member of said boom normally pivotably secured at one end of the cylinder thereof to said boom;

the improvements of boom length extension rneans comprising:

a boom extension member attachable to said boom and having a plurality of portions selectively registrable with said journal member of said boom,

means limiting the motion of said boom extension member with respect to said boom member to linear sliding movement to accommodate registration of one of said registratable portions with said boom journal member,

means statically fixing said boom extension member on said boom member when one of said boom extension member portions registers with boom journal member,

means pivotally securing said boom extension member to said dipper stick assembly,

and means pivotally securing said boom extension member to said one end of said cylinder.

5. Boom length extension means, adapted to be fitted over the end of a boom journalable with a dipper stick assembly of a hydraulically actuated tractor mounted backhoe, cooperating with a hydraulic cylinder and rod assembly normally journalably connected on said boom and operable to pivot said dipper stick assembly, comprising:

a member open at one end and for over-fitting said boom end and carrying means for journalably connecting said over-fitting means to said dipper stick assembly,

means selectively movable for attaching said over-fitting member on the boom;

fastening means for selectively orienting the over-fitting member in any one of several fixed positions with respectto said boom end,

and means pivotably mounted on said over-fitting member journalably connected to said hydraulic cylinder and rod assembly.

6. On a tractor mounted, hydraulically controlled trenching apparatus comprising:

a vertically hinged trenching support,

a boom horizontally journaled on said support and having a journal member,

a dipper stick assembly journalable upon said journal member of said boom,

a hydraulic cylinder and rod assembly for rotating said dipper stick assembly with respect to said journal member of said boom,

and a bucket pivotably connected to said dipper stick,

the method of extending boom length comprising:

overlaying said boom in a translatable telescopic fashion a rigid member journable upon said journal member of said boom at a plurality of corresponding journal members on said rigid member;

journaling said dipper stick member upon said rigid member;

and providing a pivot point for said hydraulic cylinder and rod assembly on said rigid member for a pivotable mounting therewith.

References Cited by the Examiner UNITED STATES PATENTS 1,650,255 11/1927 Bannister 2l4-134 2,575,564 1l/195l Rinkel 214- 2,784,855 3/1957 Acker 214-138 2,984,372 5/1961 Ferwerda 2l4-l38 HUGO O. SCHULZ, Primary Examiner.

Claims (1)

1. 2. IN A TRACTOR MOUNTED BACKHOE HAVING A BOOM NORMALLY CARRYING A DIPPER STICK PIVOTALLY MOUNTED AT ONE END THEREOF AND HAVING AN ACTUATING CYLINDER ANCHORED TO SAID BOOM AND A PISTON ROD PIVOTED TO SAID DIPPER STICK, THE IMPROVEMENTS OF A BOOM EXTENSION ELEMENT OF HOLLOW BOX-LIKE CONFIGURATION TELESCOPICALLY SLIDABLE OVER SAID BOOM, INTERENGAGING SLIDE MEANS ON SAID BOOM, SAID EXTENSION ACCOMMODATING RELATIVE TELESCOPIC BOOM-EXTENSION MOVEMENT, AN ANCHOR BRACKET ON SAID EXTENSION TO WHICH SAID CYLINDER IS ATTACHABLE, SAID EXTENSION HAVING A PAIR OF SPACED APERTURES SELECTIVELY REGISTRABLE WITH SAID ONE END OF SAID BOOM, AND MEANS SELECTIVELY INSERTABLE THROUGH

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