US 3436099 A
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A ril 1, 1969 E5. LONG 3,436,099
LOCKING APPARATUS FOR SIDE SHIFTABLE EXCAVATOR Filed Nov. 7, 1967 Sheet of 2 ELTON 5.LONG
SETTLE, BATCHELDER a OLWAN. 7:0. 2
E. B. LONG Aprifi 1, 1969 LOCKING APPARATUS FOR SIDE SHIFTABLE EXCAVATOR Sheet g of 2 Filed Nov. 7, 1967 lmre ntor. ELTON 5. Lowe 8v SETTLE,BATCHELDER aoLmwv 3,436,099 LOCKING APPARATUS FOR SIDE SHIFTABLE EXCAVATOR Elton B. Long, Burlington, Iowa, assignor to J. I. Case Company, Racine, Wis., a corporation of Wisconsin Filed Nov. 7, 1967, Ser. No. 681,162 Int. Cl. B60d 7/00 U.S. Cl. 280456 1 Claim ABSTRACT OF THE DISCLOSURE A mechanical locking mechanism for securing a mobile frame of a side shiftable evacuating device to an immobile frame of the device in any one of an infinite number of positions. The mechanism includes pressure pads adapted to be forced into engagement with bearing surfaces of rails forming part of the immobile frame. The pads are pressured through a mechanical force supplied by the operator and transmitted to the pads by grease contained in suitable lines.
BACKGROUND OF THE INVENTION The present invention relates generally to a side shiftable excavator, such as a backhoe, and more particularly to a novel system for mechanically looking a side shiftable or mobile frame which carries an earth working implement, such as a backhoe assembly, in any one of an infinite number of positions along a fixed and immobile frame which is carried by the tractor chassis.
In the past, it has been common commercial practice in the excavating art to mechanically lock the mobile frame of an excavator, such as a backhoe, to an immobile frame. Such mechanical locks, previously used, include frame connections such as: (1) a fixed number of aperture positions in the immobile frame and through one of which a bolt assembly is to extend, which bolt assembly may be tightened mechanically to secure the mobile frame in a desired position (for example, see United States Patent 3,139,199) and (2) a pair of horizontal slots positioned at different elevations in the immobile frame and through which passes one or more bolt-s, which bolts are also attached to the mobile frame and may be mechanically tightened to lock the mobile frame in the desired position (for example, see United States Patent No. 3,156,488).
These types of mechanical locks are objectionable since repositioning of the mobile frame is costly, time consuming, and annoying, requiring that the operator dismount the excavator, mechanically loosen the lock by use of a wrench or the like, remount the excavator, resituate the mobile frame in the desired new position with respect to the immobile frame by use, for example, of the bucket and crowd cylinder, again dismount the excavator, mechanically tighten the lock by use of the wrench or the like, and again remount the tractor for further excavation. Furthermore, such mechanical locks tend to loosen during excavation, requiring expenditure of further excessive time and attention. These mechanical locks also often encounter mechanical interference which makes locking impossible or extremely difiicult due to component misalignment (such as misalignment of matching apertures in the mobile and immobile frames) resulting from wear, abuse and the like. In addition, the versatility of the prior art excavators of the side shiftable type have been limited since almost all of such mechanical locking devices have only a fixed number (such as 4, 6, 8 etc.) of positions in which the mobile frame may be locked.
States Patent In an effort to overcome these objections, a hydraulic system has been proposed which will lock the mobile frame in any one of an infinite number of positions along the immobile frame and may be actuated by the operator without dismounting from the excavator. Such a system is disclosed in my Patent No. 3,304,100 assigned to the assignee of the present invention.
SUMMARY OF THE INVENTION The present invention incorporates the advantageous features of a hydraulic locking system of the abovementioned Patent No. 3,304,100 while providing a handoperated mechanical control for locking the mobile frame on the fixed frame.
Accordingly, the primary object of this invention is to provide improved apparatus for mechanically locking the mobile frame of a side shiftable evacuator in any one of an infinite number of positions along the immobile frame.
Another object is the provision in a side shiftable excavator of apparatus for mechanically locking the mobile frame in a desired position which eliminates the need for the operator to leave his seat upon the excavator in order to so reposition the mobile frame and in which the operator has control over the locking forces between the frames.
These and other objects and features of this invention will become more fully apparent from the following description and appended claims in conjunction :with the accompanying drawings wherein:
FIGURE 1 is a perspective view of a tractor mounted side shiftable backhoe equipped with the locking system of this invention;
FIGURE 2 is a cross sectional view taken along 2-2 of FIGURE 1 illustrating the locking mechanism of this invention in the open or unlocked position; and
FIGURE 3 is a cross sectional view similar to FIG- URE 2 illustrating the locking mechanism of this invention in its retracted, locked or closed position.
GENERAL Reference is now made to the drawings wherein like numerals are used to designate like parts throughout.
FIGURE 1 illustrates, in perspective, a tractor-mount backhoe generally designated 10, which comprises a tractor 12 having rubber tires 14, a steering wheel 16, a drivers seat 18 and a chassis 20. The tractor 12, of course, is only representative of one of several types of tractors which could be utilized in conjunction with the present invention. Naturally, track-mounted tractors are also encompassed by the present invention.
Generally, the embodiment depicted in the drawings structurally includes a fixed or immobile frame, generally designated 22, which is integrally fastened to the tractor chassis 20 by forwardly projecting ears (not shown) or the like carried by the immobile frame 22 and secured to attachment arms (not shown) on the tractor chassis 20.
A side shift or mobile frame 50 is carried by the immobile frame 22. A swing post 40 is pivotably supported by the mobile frame 50 and carries, in a conventional manner, a backhoe assembly which comprises a boom cylinder 152, an anchor bracket 154 and a boom 156, a dipper stick or crowd cylinder 158, a triangularly shaped pivotable bracket 160, a dipper stick 161, a bucket cylinder 162, links 164 and 166 and a bucket 168. The backhoe assembly 150 per se constitutes part of the prior art.
THE IMMOBILE FRAME The immobile frame 22 along with the general manner in which the mobile frame 50 is carried in a slide rail and slide rail guide arrangement by the immobile frame 3 22 constitutes part of the invention of co-pending application Ser. No. 449,966, filed on Apr. 22, 1965 and now Patent No. 3,371,435 and assigned to the assignee of the present invention. The immobile frame 22 comprises two generally horizontally extending beams 24 and 26, of hollow rectangular cross sectional configuration, which are joined by welding or the like to the rear side 28 of a pair of transversely spaced, vertically extending columns 30 and 32, also preferably of hollow rectangular cross sectional configuration. The welds so joining the beams 24 and 26 to the columns 30 and 32 are identified by the numerals 34. The upper beam 24 is further supported by a pair of diagonally disposed braces 25, fabricated preferably from hollow rectangular cross sectional stock, which are welded or otherwise secured to the faces 28 of the columns 30 and 32 at 61 and to the beam 24 at 63.
The rear faces of each of the beams 24 and 26 carry vertically disposed plates 36 and 38, preferably of solid rectangular cross section. These plates 36 and 38 constitute slide rails and are preferably welded or otherwise integrally secured at the rear faces of the beams 24 and 26. The slide rails 36 and 38, as can be seen by inspection of the figures, are vertically aligned with each other at different elevations and extend generally horizontally, with the top slide rail 36 projecting above the beam 24 and the bottom slide rail 38 projecting beneath the beam 26.
Integrally attached to the lower beam 26, as by welding, are three members including an angularly-shaped member 120, a horizontally disposed plate 122 and a vertically disposed plate 124. In combination, the angle 120 and the plates 122 and 124 constitute a bracket generally designated 126. The bracket 126 supports the stabilizer or outrigger legs 128 (FIGURE 1), each of which have a ground engaging pedestal 130. The stabilizer legs 128 (one of which is illustrated in FIGURE 1) are pivotably mounted to the downwardly extending portion of the angularly-shaped member 120 and to the vertically disposed plate 124 by means of a pin and aperture assembly (not shown).
THE MOBILE FRAME The swing post 40 of the overall excavator 10 is mounted on the generally vertically extending side shiftable or mobile frame 50, as previously stated. The mobile frame 50 spans the distance between the slide rails 36 and 38. This mobile frame is rectangular in outline and considerably smaller than the immobile frame 22. The mobile frame 50 carries with it an excavator operators seat 52 and a control panel 54 having a cover 56. The mobile frame 50 is slidable, under certain conditions, along the previously described slide rails 36 and 38 f the immobile frame 22.
The mobile frame 50 structurally comprises a pair of vertically extending columns 58 and 60 integrally connected to a top plate 62 (which carries the control panel 54 and the cover 56) and to a bottom support plate 64. The top support plate 62 and the bottom support plate 64 each have an integral ear 66 and 68, respectively, upon which the swing post 40 is pivotally mounted by connecting pins (hidden from view). The swing post 40 is hydraulically rotatable responsive to actuation of a pair of swing cylinders, only one of which is illustrated in the figures, being indentified by the numeral 70.
The mobile frame 50 is slidably carried by the immobile frame 22 along the two slide rails 36 and 38 and is provided with two top slide rail guides, generally designated 72, and two bottom slide rail guides, generally designated 74. The upper slide rail 36 and the two guides 72, in combination, constitute primary load-carrying members in that the downward vertical load imposed upon the immobile frame 22 by the backhoe assembly 150 and by the mobile frame 50 is transmitted through the plate 62 solely to the top surface 76 of the slide rail 36. No downward vertical load is transmitted to the lower slide rail 38.
Each upper slide rail guide 72 comprises a back-up stop block 78 integrally secured to the top plate 62 as by welding, a bottom stop block 80 integrally secured to the columns 58 and 60 of the mobile frame 50 at 84 (which contacts the bottom 86 of the upper slide rail 36 to transmit any upward thrust generated during excavation and the like), and a pressure bearing pad or ram 88 providing a pressure bearing surface 90. The pressure bearing pad or ram 88 is integrally connected to a piston 92 which is reciprocably carried within a casing 93 of a cylinder assembly 94. Each of the two cylinder assemblies 94 is illustrated as being a one way cylinder and the pads 88 are actuated by pressured grease, as will be described hereinafter.
Each lower slide rail guide 74 comprises a back-up stop member 96 providing a pressure bearing surface 98 (the back-up stop 96 being integrally attached at the bottom to the columns 58 and 60) and a pressure bearing pad or ram 100 providing a pressure bearing surface 102 (the pressure bearing pad or ram 100 being integrally attached to a piston 104 reciprocally disposed within a casing 105 of a cylinder assembly 106). The pressure bearing pads are pressured by grease as will be presently described.
In my previous Patent No. 3,304,100, the pressure hearing pads 88 and 100 are actuated-by pressured hydraulic fluid from the hydraulic system of the tractor. According to the present invention, the pads and are forced into engagement by utilizing a pressure transmitting means which is in the form of a semi-solid mass, such as grease, for transmitting the forces applied by a manually operated control member or pump. This arrangement provides the operator with an accurate control of the amount of force applied to the pads during the locking of the mobile frame on the fixed frame.
The manually controlled pressuring means includes a conventional grease gun 200. The grease gun may be of the type disclosed in Davis Patent No. 2,425,867. The grease gun 200 comprises a reservoir 202 having a pump 204 secured to one end thereof which is actuated through a manual controlled lever 206. The reservoir is fixedly secured to the panel 56 by U-shaped brackets 208 and has a piston rod 210 with a T-handle 212 reciprocating therein and preferably spring biased in a conventional manner to maintain the grease within the reservoir at a predetermined pressure.
The pressure outlet of the pump 204 has a conduit 216 connected thereto with a manually operated valve 218 therein. A bypass circuit connects the conduit 216 with the reservoir 202 at a point below the valve 218. This bypass circuit includes a hand valve 220 in a conduit 222 which is connected to the reservoir 202. The bypass conduit also is in communication with a valve 223 so as to perform the dual function of providing a bypass between the reservoir and the conduit 216 as well as a circuit for filling the grease gun, as will be presently described.
Parallel circuits 224 are connected to the conduit 216 and since they are identical in construction, only one will be described in detail. Thus, circuit 224 includes a conduit 230 connected by a T connector 232 to the cylinder casing 93 and to a conduit 234. The conduit 234 is also connected through a fitting 236 to the second cylinder casing 105. The connector 232 and fitting 236 may incorporate valves so that the communication between pump 204 and casings 93 and may be selectively controlled.
In operation, the grease gun 200' is first filled with a semi-solid fluid mass, such as grease, by closing valve 220 and opening valve 223. In this manner, grease can be forced into the reservoir 202 and the spring biased piston rod 210 will be forced upwardly as viewed in FIGURE 1. When a sufficient amount of grease has been provided, the valve 223 is closed.
To lock movable frame on the fixed frame, the valve 218 is opened thus placing the pump 204 in open communication with the respective cylinder assemblies 94 and 107. The pump is thereafter actuated through the manual control lever or handle 206 to pressure the grease within the parallel circuits 224 thus forcing the pistons 92 and 104 into the extended position thereby engaging the respective pads 90 and 100 with the railings 36 and 38 to securely lock the mobile frame on the stationary frame. As can readily be appreciated, the manually operated grease gun provides a means for accurately controlling the amount of pressure applied to the respective pistons 92 and 104 and is at all times within the exclusive control of the operator. Furthermore, the grease gun 200 is positioned so as to be readily accessible to the operator while he remains at the operating station of side shiftable backhoe.
Once a sufiicient amount of pressure is applied to the grease within the circuits 224, the valve 218 is closed to thus trap the pressured grease within the respective circuits 224 and maintain the pads 90 and 100 in the locked position. Whenever it is desired to shift the backhoe with respect to the vehicle, it is only necessary to open the bypass valve 220 located in the bypass circuit or conduit 222 to thereby relieve the pressure within the circuits 224 by allowing the grease to return to the reservoir 202.
Of course, the respective pistons of the cylinder assemblies will be retracted suificiently by the normal forces between the mobile frame and the fixed frame to allow shifting of the mobile frame on the respective rails. When the mobile frame has been repositioned to the desired position with respect to the rails, valve 220 is again closed and valve 218 opened to allow pressuring the respective pistons of the cylinder assemblies. This is accomplished by actuating the hand lever 206 until a suflicient pressure has been applied to the grease within the circuits 224. Again the valve 218 may be closed to trap the grease within the parallel circuits 224 as well as the casings of the cylinder assemblies.
From the above description, it can be readily appreciated that the invention provides an accurately controlled means for locking a mobile frame on a fixed frame of a side shiftable backhoe. Furthermore, the amount of pressure applied to any of the pistons is Within the exclusive control of the operator while he is stationed in the normal operating position of the excavator. Of course, the amount of pressure which may be applied can readily be varied by varying the type of pump 204.
While one exemplary embodiment of the invention has been described in detail, it will be apparent to those skilled in the art that the disclosed embodiment may be modified. Therefore, the foregoing description is to be considered exemplary rather than limiting, and the true scope of the invention is that defined in the following claim.
1. In combination with a side shiftable excavator adapted to be attached to a vehicle and having a fixed frame including upper and lower slide rails each defining first and second substantially vertical bearing surfaces, fixed means carried by said mobile frame for engaging said first bearing surfaces, bearing pads carried by pistons slidable in cylinders supported on said mobile frame for engaging said second bearing surfaces, a control system for moving said pistons comprising a reservoir supported on said mobile frame, first conduit means connecting said reservoir to said cylinders, a manual pump in said first conduit means, second conduit means bypassing said manual pump and connecting said reservoir to said cylinder a semi-solid flowable mass in said reservoir and said conduit means, and valve means in said first and second conduit means and selectively actuatable to place said reservoir and said pump in fluid communication with said cylinders to extend and retract said pistons in said cylinders for locking said mobile frame to said fixed frame in any one of an infinite number of positions.
References Cited UNITED STATES PATENTS 770,101 9/1904 Nilson 188-152 1,743,005 1/1930 'Resler -52 X 2,138,263 11/1938 Van Cleave et al. 60-52 X 3,304,100 2/1967 Long 280-456 2,449,335 9/1948 Sowa 188-100 FOREIGN PATENTS 1,169,734 7/1958 France.
972,208 10/ 1964 Great Britain.
975,029 11/1964 Great Britain.
984,383 2/ 1965 Great Britain.
355,915 9/ 1961 Switzerland.
LEO FRIAGLIA, Primary Examiner.
US. Cl. X.R.