US2391538A - Front end loader - Google Patents

Description

' Dec. 25, 1945. w. ARMSTRONG FRONT END LOADER 3 SheetsSheet 1 Filed March 1'7, 1945 -o mn o M. 1m r H M U 5 E N R O T T A Dec. 25, 1945. w, ARMSTRONG 2,391,538

FRONT END LOADER Filed March 17, 1945 5 SheetsSheet 2 INVENTOR wayneflrmslrongi ATTORNEYS Dec. 25, 1945. w. ARMSTRONG FRONT END LOADER 3 Sheets-Sheet 5 Filed March 17, 1945 INVENTOR ,ZUa yne firms iron? Zuni: YZULAZL/ ATTORNEYS a. R 5 ww mm. x 1 f. A! W E Y mm B QN P E. R Q Q m 1 N n mm Q N Q 9v m R mm wm N \R mm mm m N\ %N Q N r mc m m N N S E 2 k 9 mm x a m g nfij i'atented Dec. 25, 1945 UNITED STATES PATENT OFFICE- FRONT END LOADER Wayne Armstrong, Woodland, Calif. Application March 17, 1945, Serial No. 583,218

Claims. (01. 214-139) i This invention is directed to, and it is an object to provide, an improved tractor mounted front end loader; such loader including transversely spaced push beams having a scoop mounted on the front end thereof, and said push beams being vertically swingable to elevate the scoop from a digging position at the ground to a dumping position some distance above the ground.

Another object of the invention is to provide a front end loader, as above, which includes a novel push beam assembly arranged so that when the beamsare lowered, the scoop digs close to the tractor as is desirable, but advances the scoop when the beams are elevated whereby said scoop dumps some distance ahead of the tractor, whichfacilitates loading of a truck or the like. I

A further object of the invention is to mount the push beams so that when in lowered position for digging by the scoop, the thrust of the tractor to the push beams is advantageously applied to the latter at the rear end and from adjacent the rear axle of said tractor.

An additional object is to incorporate a novel brake unit in the power actuating mechanism for the push beam and scoop assembly.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects are accomplished such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views:

Figure 1 is a side elevation of the front end loader in use, with the scoop in digging position.

Figure 2 is a similar view but with the scoop in elevated or dumping position.

Figure 3 is a plan view of the front end loader mounted on a tractor.

Figure 4 is an elongated, fragmentary, longitudinal, section of the brake'unit. A

Figure 5 is a cross section on line 5-5 of Fig. 4.

Referring now more particularly to the characters of reference on the drawings, the implement comprises a supporting frame including transversely spaced, longitudinally extending frame beams I adapted to extend in rigidly secured relation along opposite sides of a wheel tractor. 2 or the like. Rigid A-frames 3 are fixed in connection with and upstand from the longitudinal frame beams I on opposite sides of the by means of tractor engine; said A-frames each including a front brace l and a rear brace 5.

A pair of transversely spaced push beams 8 are disposed on opposite sides of the tractor, said push beams extending outside the front wheels I but inside the rear wheels 8 of said tractor. The push beams 6 are disposed parallel to each other and at, their forward ends straddle a scoop 9, said forward ends of the push beams being pivoted to the sides of the scoop intermediate the front and rear of the latter, as at III, whereby the scoop.can tilt from a digging and loading position relative to the push beams, as in Fig.1, to the discharge or dumping position, as in Fig. 2.

A cross bar I I connects between the push beams 6 to the rear of the scoop 9 and supports a latch unit I2 adapted to normally engage in latching relation over the upper edge of a vertically adjustable back wall portion I3 of the scoop. A flange It on the lower edge of the back wall I3 limits rearward rotation of the scoop 9 when the latter is latched in digging position. The latch unit I2 is spring-engaged with the back wall I3, and adapted to be released by a pull cord I5 which leads rearwardly from said latch unit along one of the push beams 6 to connection with a.

pivotally mounted lever I6 mounted on said push beamintermediate the ends of the latter. The lever I6 is adapted to be swung in a latch releasing direction by another, normally slack pull cord II which leads from said lever I6 rearwardly to adjacent the operator's seat I8 of the tractor.

By reason of this dual pullcord and lever arrangement, the push beams 6 can swing up and down in the manner hereinafter described without affecting the pull cord I5.

The advantage of the vertical adjustability of the back wall I3 resides in the fact that such adjustment permits the scoop 9 to be set with the lip or forward cutting edge I9 thereof at varying digging angles relative to the ground,

and as working conditions may require.

The push beams 6 are mounted for vertical swinging movement, and so that said beams automatically advance upon elevation thereof, by means of the following arrangement: At their rear ends the push beams 6 attach, in articulated relation, to rigid links 20; said links being pivotally connected at one end to th push beams 6, as at 2|, while the other ends of said links are pivotally connected, as at 22', to cars 23 which project forwardly from the upper ends of up standing attachment brackets 24 fixed in connection with the corresponding longitudinal frame beams I, and abutting adjacent their lower ends against the rear axle housing 23 of the tractor inwardly of the rear wheels 3 of the latter. d

The links normally depend from the cars 23 in the manner shown in Fig. 1, and at which time the rear ends of push beams 6 abut against the lower portions of brackets 24 directly ahead of the rear axle housing 25. This is the position of the push beams when the scoop 9 is in lowered or digging position; said push beams then being disposed at a forward and down-- ward incline, as shown in Fig. 1. When the scoop 3 is in digging position it is disposed ahead of but closely, adjacent ,the front wheels I of the tractor 2. With advance of the tractor the cutting edge 9 of the scoop digs into the earth and the dug portion thereof is forced rearwardly into the scoop 9 to fill the latter. After the scoop is filled the assembly of push beams 3 and said scoop is raised and advanced to a' dumping position, as in Fig. 2, by the following means:

Intermediate their ends the push beams 6 each include a pivotally mounted slide 26 which engages in cooperative relation with a forwardly and upwardly inclined guide rail 21 included in the corresponding A-frame 3. A pair of cabletype block and tackle systems 28 connect between the push beams 6 directly ahead of the slides 28 and the upper end portion of the corresponding A-frames 3, each block and tackle system 28 including a pull lead 29 which extends rearwardly to and about a corresponding drum 30 on a crossshaft 3| Journaled between the A-frames 3. The cross shaft 3| is driven by power means which will hereinafter be described. Upon rotation of the drums 30 in a direction to wind the pull leads 29 onto said drums, the block and tackle systems 28 are simultaneously and equally shortened, which causes the assembly of push beams 6 and scoop 9 to elevate. With such elevating movement of the assembly of push beams 6 and scoop 9, th same is advanced as the slides 26 ride up the guide rails 21; the articulated links 2!) swinging forward and upwardly from the dependent position of Fig. 1 to the forwardly extending position of Fig. 2. The advance of the push beams 3 is such that the links 20 do not pass upwardly beyond dead-center but approach the same.

It will thus be seen that when the push beams 6 are fully elevated the scoop 9 is materially advanced relative to its digging position, which is advantageous for the purpose of loading into the body of a dump truck or the like, as it is unnecessary for the tractor to approach as close to the truck as would otherwise be necessary.

When the scoop 9 is loaded and raised to dumping position a pull on cord |1 causes a release of the latch unit l2, whereupon the scoop dumps forwardly under the influence of the load; there being pull-back springs 33 which then automatically return the scoop to its latched position.

To return the assembly of push beams 6 and scoop 9 to digging position the drums 30 are permitted to rotat in a reverse direction and said assembly to lower by gravity. Springs 32 connected between the rear ends of the push beams 6 and the lower end of the attachment brackets 24 are under tension when said push beams are elevated, and function to assure proper initial articulating or knuckle action between the push beams 6 and the links 20 when the scoop is to be returned from elevated digging position.

The mechanism for the actuation and control of the shaft 3|, together with the drums 39 thereon, comprises the following:

The shaft 3| is driven from a countershaft 34 by means of an endless chain and sprocket unit 5 35; the countershaft 34 including an end sprocket 38 driven by an endless chain 31 from a sprocket and clutch unit 38 connected to a side power take-off shaft on the tractor.

a brake unit, indicated generally at 39, associated therewith, said brake unit being operative to automatically lock the cross shaft 3| in any elevated position of adjustment of the assembly of push beams 6 and scoop 9, and being releasable by a hand lever 49 accessible to the trac- 16 tor operator.

This brake unit 39 comprises a drum 4| tumable on the shaft 3|, and a fixedbrake band 42 provided with suitable lining cooperates with such brake drum 4| on the outside; the band 42 being normally set but is arranged to be released by means of the lever 40.

Within the brake drum 4| is a plurality of circumferentially spaced arcuate shoes 43 which engage the drum 4| internally. Each of said shoes includes an inwardly projecting radial leg 44; said legs being pivoted at their inner ends as at 45 on a disc 46 provided with a hub 41 keyed to the shaft 3|. Tension springs 43 connect between the legs 44 and the disc 49 in a 30 direction to normally cause the shoes 43 to lock .with the drum 4| to prevent rotation of the shaft 3| in a'drum-unwinding direction; 1. e. opposite to the arrow in Fig. 5. When the shaft 3| is driven in the direction of the arrow, which causes pull leads 29 to wind onto drums 30 to raise the push beams 6, said shaft 3| turns relative to drum 4| in which the shoes 43 then overrun. However, immediately-upon clutch 38 being released, said shoes 43 instantaneously lock with the drum and prevent any rotation of shaft 3|, which holds the scoop in a selected elevated position. The push beams and scoop can then only be permitted to lower by releasing the brake band 42 by lever 40, which allows the disc and 45 brake shoes to turn with drum 4| as a unit.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention as set forth herein.

50 While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention as defined by the appended claims.

Having thus described the inventionpthe following is claimed as new and useful and upon which Letters Patent is desired:

1. A tractor mounted front end loader comprising push beams extending along opposite sides of the tractor, a scoop mounted on the push beams ahead of the tractor, links corresponding to and connected in articulated relation at one end to the rear ends of the push beams, the otherends of the links being pivotally connected with the tractor for vertical longitudinal swinging movement, power mechanism to raise the push beams from a lowered position with the scoop disposed for digging to an elevated position with the scoop disposed for dumping, the links being dependent relative to the tractor when the push beams are in lowered position, and means to automatically advance the push beams and scoop as the same move to elevated from lowered position; said advancing The shaft 3| has I means comprising slides mounted on the push beams intermediate their ends and cooperating with adjacent upwardly and forwardly inclined guide rails mounted in connection with the tractor.

2. A tractor mounted front end loader comprising push beams extending along opposite sides of the tractor, a scoop mounted on the push beams ahead of the tractor, means securing the push beams in connection with the tractor for upward movement between a lowered position with the scoopin digging position and an elevated position with the scoop in dumping position, power mechanism operative to move the push beams upwardly from lowered to elevated scoop and push beams operative 'to return the,

scoop after dumping to latched position.

4. A tractor mounted front end loader comprising push beams extending along opposite sides of the tractor, a scoop mounted on the push beams ahead of the tractor, the tractor including a rear axle housing, brackets abutting against said housing and mounted on the tractor in up standing relation, links pivoted at one end in connection with said brackets adjacent the upper ends of the latter, the other ends of the links being pivoted to the rear end portions of corresponding push beams, the rear ends of said push beams abutting the brackets directly ahead of the axle housing when said links are depending and the push beams are in lowered position with the scoop disposed for digging, power mechanism arranged to swing the push beams to an elevated position for dumping and means between the push beams and tractor to automatically advance said push beams and scoop upon movement thereof from lowered to elevated position, the links then swinging forwardly and upwardly.

5. In combination with a tractor, a link pivoted on each side of the tractor, such links depending downwardly from their pivot points, a push beam pivoted on the lower end of each link and projecting to a point ahead of the tractor, a scoop mounted on the outer ends of the push beams, means to resist backward swinging movement of the links whereby with the forward movement of the tractor the power of such tractor will be exerted against the links and push beams to effect loading of the scoop, means'to'

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