US 3670825 A
A power angling bulldozer comprises a blade operatively connected to the forward end of a C-frame by spaced links arranged to diverge toward each other forwardly of the frame. A pair of double-acting hydraulic cylinders are pivotally connected between the frame and blade to selectively impart angling movements to the blade for earth-moving purposes. The links are constructed and arranged so that the blade will completely cover and protect the frame during all such movements. A third double-acting hydraulic cylinder may be operatively associated with the blade to selectively impart tilting movements thereto.
Claims available in
Description (OCR text may contain errors)
United States Patent Asal et al.
[451 June 20, 1972  POWER ANGLING BULLDOZER  Inventors: Jerrold R. Asal, Joliet; Donald A. Plepho,
Aurora, both of III. 1
 Assignee: Caterpillar Tractor Co., Peoria, 111.
 Filed: Oct. 9, 1969 [211 App]. No.: 865,023
 US. Cl. ..172/805, 172/663, 172/742, 37/42  Int. Cl. ..E02f 3/76, A01b 65/00, AOlb 35/22  Field of Search 172/805, 806, 807, 276, 801 172/803, 804, 802, 741, 742, 667, 763, 663; 37/41, 40; 280/456, 460, 467
 References Cited UNITED STATES PATENTS 2,001,803 5/1935 Stephens 172/809 2,100,445 1 1/1937 Bleu ..172/807 2,374,016 4/1945 l-lenneuse. ..172/807 2,734,292 2/1956 Graves ..172/804 2,816,772 12/1957 La Pointe ..37/41 X 2,950,550 8/1960 French 172/804 FOREIGN PATENTS OR APPLICATIONS 818,632 8/1959 Great Britain 1 72/2 76 Primary Examiner-Robert E. Pulfrey Assistant Examiner-Stephen C. Pellegrino AttorneyFryer, Tjensvold, Felix, Phillips & Lempio  ABSTRACT A power angling bulldozer comprises a blade operatively connected to the forward end of a C-frame by spaced links arranged to diverge toward each other forwardly of the frame. A pair of double-acting hydraulic cylinders are pivotally connected between the frame and blade to selectively impart angling movements to the blade for earth-moving purposes. The links are constructed and arranged so that the blade will completely cover and protect the frame during all such movements. A third double-acting hydraulic cylinder may be operatively associated with the blade to selectively impart tilting movements thereto.
13 Claims, 4 Drawing Figures PATENTEnJum I972 I 8, 670. 825
INVENTORS JERROLD R. ASAL. DONALD A. PIEPHO BY g I f .4! .M ,L
g 05 ATTORNEYS P'A'T'ENTEnJuxzo m2 3, 570, 82 5 SHEET 2 OF 3 INVENTORS JERROLD R. ASAL DONALD A. PIEPHO vP'A'TENTEIJJUM2o 1972 3, s70 825 SHEET 3 OF 3 FNVENTORS JERROLD R. ASAL DONALD A. PIEPHO I BY WW ATTORNEYS POWER ANGLING BULLDOZER It is desirable to completely cover and protect the forward end of the C-frame of a bulldozer during all phases of an earthmoving operation. Conventional blades normally comprise a length substantially greater than the width of the C- frame and attached tractor to provide such protection. However, due to various regulations regarding the transport of the tractor-type bulldozer, the tractor and blade must be shipped separately and then operatively connected together once they reach their destination. For example, certain regulations specify a maximum width of 8 feet for certain equipment which is transported by flatbed truck, thus precluding the intact shipment of many conventional bulldozers in the absence of a special permit and/or routing.
An object of this invention is to provide an efiicient and economical linkage means, exhibiting a high degree of structural integrity and simplicity, for pivotally connecting an angling implement to a support therefor. Such linkage means is particularly adapted to overcome the above, briefly described problems by connecting the blade and C-frame of a bulldozer together to permit them to remain intact during transportation and yet permit the blade to fully protect the C-frame during all phases of operation thereof. In the hereinafter described preferred embodiment of this invention, such linkage comprises a pair of links positioned to converge toward the implement.
Other objects of this invention will become apparent from the following description and accompanying drawings wherein:
FIG. I is a partial, top elevational view of a bulldozer embodying the linkage means of this invention therein for pivotally connecting the blade assembly to a forward end of a C-frame thereof;
FIG. 2 is a view taken in the direction of arrows II-Il in FIG. 1;
FIG. 3 is a cross-sectional view taken in the direction rows llI-Ill in FIG. 1; and
FIG. 4 is a view similar to FIG. 1, but schematically illustrating various angling dispositions of the blade relative to the attached C-frame.
The bulldozerillustrated in FIG. 1 is symetrically disposed on a central longitudinal axis X (FIG. 4) thereof. The bulldozer comprises a support ofC-frame having a blade assembly ll pivotally connected to a forward end portion thereof by linkage means, shown in the form of spaced links 12 and 13. The C-frame is adapted to have the free ends of its parallel side arms pivotally attached by universal connections to a tractor (not shown) in a conventional manner for earthmoving purposes.
of ar- Standard double-acting hydraulic cylinders 14 and 15 are preferably pivotally connected in diverging relationship between the C-frame and blade assembly and have the linkage means disposed therebetween. The cylinders are adapted to be incorporated into a conventional control circuit (not shown) to be alternately extended and retracted for angling the blade. Various blade angling positions are schematically illustrated in FIG. 4.
A blade 16 of the blade assembly has a stub shaft 17 secured to the backside thereof (FIG. 3) to be disposed on the central longitudinal axis of the bulldozer. The stub shaft is journaled for rotation in a U-shaped member 18 having upper and lower parallel flanges l9 and 20, respectively. A double-acting hydraulic cylinder 21 (FIGS. 1 and 2) has its head end pivotally mounted to an upstanding bracket secured to blade 16 by a pin 22.
The cylinders rod end is pivotally mounted on an upstanding lug 23, secured to flange 19, by a pin 24. The outer ends of member 18 are preferably arcuate and are overlapped by positioning plates 25 and 26 secured to blade 16. Such an overlapping relationship provides a bearing support to aid in counteracting undue loads which may be imposed on the blade and stub shaft 17 during vehicle operation.
It can be seen that selective extension and retraction of cylinder 21 will function to tilt blade 16 relative to bracket 18 and about stub shaft 17. The cylinder may be suitably incorporated into the above-mentioned hydraulic control circuit which may further include cylinders 14 and 15. It should be further understood that other types of earth-moving implements, such as a loader bucket, may be utilized in lieu of blade assembly 11.
The degree of angling movements imparted to the blade assembly by cylinders or actuating means-14 and I5 is controlled by links 12 and 13, pivotally connected between the frame and blade assembly by pivot pins 27-28 and 29-30, respectively (FIG. 1). As shown in FIG. 2, pins 28 and 30 extend through forward end portions of the links and are each pivotally connected between spaced flanges l9 and 20 of member 18. The rear end portions of the links are preferably bifurcated to increase the structural integrity of the integrated assembly and to continuously maintain member 18 in an erect position relative to the C-frame.
Referring to FIG. 4, the maximum included angle a through which the blade or other suitable earth-working implement may be angled would be dictated by the particular earth-working application. In one commercial bulldozer embodiment of this invention it was found that an angle a approximating 50 (the blade angle equalling 25) was adequate for efficiently performing the earth-moving operations in question. Links 12 and 13 preferably diverge toward blade 16 and normally form a trapezoid along with imaginary lines between pivot pins 27-29 and 28-30, when the blade is maintained in its normal erect position perpendicular to longitudinal axis X of the bulldozer.
The included angle b between the links, angle c depicting the angle through which each link is moved, the distances between pivot pins 27 and 29 and 28 and 30, the lengths of the links and related design parameters would be considered together for any particular design application. In the bulldozer application under consideration, the design parameters are such so as to continuously maintain the blade close to the C- frame and to assure that the maximum angled length of the blade does not exceed the width of the C-frame. The latter desiderata assures that the C-frame, having a width closely approximating 8 feet, for example, will be fully protected during all of the blades angled positions. ln-addition, pivot pins 27 and 29 are suitable spaced from each other to enable the links to perform their desired functions, but are not positioned too far apart to interfere with the angling movements of cylinders 14 and 15. The cylinders are kept as close togetheras possible to enable them to fit into the prescribed space, but yet far enough apart to prevent excessive forces from damaging the cylinders, lines and related structures.
In the illustrated embodiment it was further found desirable to maintain each link 12 and 13 at a length approximating one-half the distance between the pivot pins 27 and 29. Such an arrangement was found to provide maximum flexibility in obtaining the desired blade angle and lateral movement for the design under consideration. In such design, the preferred length of each link approximates twelve inches, whereas the included angle b between the links approximates 60. A larger angle will tend to reduce the degree of lateral movement afforded to the blade during angling whereas a smaller angle will tend to reduce angling angle a.
It should be noted that the links have an instantaneous point of intersection P (FIG. 4) which comprises an imaginary pivot point for angling the blade. When the blade is angled to its dotted line position the point moves to P. Thus it can be seen that the point moves rearwardly toward the C-frame as well as laterally outwardly when the blade is angled.
1. In an angling apparatus comprising an implement attached to a support normally disposed at least generally horizontally and adapted to be attached to a vehicle and means pivotally interconnecting said implement and said support for angling said implement relative to said support, the invention comprising linkage means, consisting of a pair of links normally disposed at least generally in the same horizontal plane and positioned to converge toward said implement from said support, pivotally connecting said implement to a forward end of said support for permitting said implement to pivot solely about an infinitely variable pivot axis disposed forwardly of said linkage means and means for maintaining said implement in a selected pivoted position.
2. The invention of claim 1 wherein said support and implement are the C-frame and blade assembly of a bulldozer, respectively.
3. The invention of claim 2 wherein the means for maintaining said implement in a selected pivoted position comprises at least one actuating means operatively connected between said blade assembly and a forward portion of said C-frame for selectively angling said blade assembly relative to said C- frame.
4. The invention of claim 3 wherein said actuating means comprises at least one hydraulic cylinder pivotally connected between said C-frame and said blade assembly.
5. The invention of claim 4 wherein two of said cylinders are pivotally connected between said C-frame and said blade assembly, said linkage means positioned between said cylinders.
6. The invention of claim 3 wherein said blade assembly comprises a member pivotally connected to said linkage means and said cylinder and a blade pivotally and tiltably mounted to said member and further comprising means operatively connected between said blade and member for selectively tilting said blade relative to said member.
7. The invention of claim 1 wherein the included angle between said links approximates 60 calibrated at the pivot point.
8. The invention of claim 7 wherein said links are positioned approximating 50.
9. An angling apparatus comprising a support disposed at least generally horizontally on a central longitudinal axis thereof and adapted to be pivotally attached to a vehicle, an implement positioned forwardly of said support and normally disposed at least generally horizontally and transversely relative to said axis, actuating means pivotally interconnecting said implement and said support for selectively angling said implement relative to said support and for maintaining said implement in a selected angled position, and a pair of links at least generally disposed in the same horizontal plane and pivotally connecting said implement to said support and positioned to converge toward said implement from said support for pemiitting said implement to pivot solely about an infinitely variable pivot axis disposed forwardly of said links.
10. The invention of claim 9 wherein said support and implement are the C-frame and blade assembly of a bulldozer, respectively.
11. The invention of claim 10 wherein said blade assembly comprises a member pivotally connected to said links and a blade pivotally and tiltably mounted to said member for tilting movements about said axis and further comprising means operatively connected between said blade and member for selectively tilting said blade relative to said member.
12. The invention of claim 9 wherein the included angle between said links approximates 60 calibrated at the pivot point.
13. The invention of claim 12 wherein said links are positioned for permitting angling of said blade through an in cluded angle approximating 50.