US2530414A

US2530414A - Combined bulldozer and tractor shovel

Info

Publication number: US2530414A
Application number: US27993A
Authority: US
Inventors: Robert L Wells
Original assignee: Bucyrus Erie Co
Current assignee: Caterpillar Global Mining LLC
Priority date: 1948-05-19
Filing date: 1948-05-19
Publication date: 1950-11-21
Anticipated expiration: 1967-11-21

Description

Nov. 21, 1950 R. L WELLS 2,530,414

COMBINED BULLDOZER AND TRACTDR SHOVEL Filed May 19, 1948 2 Sheets-Sheet 1 mmvron,

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Patented Nov. 21, 1950 COMBINED BULLDOZER AND TRACTOR SHOVEL Robert L. Wells, Douglas, Ga., assignor to Bucyrus-Erie Company, South Milwaukee, Wis., a corporation of Delaware Application May 19, 1948, Serial No. 27,993

2 Claims. Cl. 214-140) My invention relates to new and useful improvements in tractor-mounted material-handling implements, more particularly to tractor shovels modified to both push, as well as carry dirt.

In a machine of the type to which my invention is more particularly adapted, the implement is usually designed for attachment to a conventional tractor and consists of a transverse bucket, two arms pivoted on the tractor for pushing and lifting the bucket, and means to raise and lower the arms. The last-mentioned means usually consists of one or two hydraulic cylinders actuated by a pump driven by the engine of the tractor. The bottom of the bucket is usually concave toward the front in vertical cross-section, the ends being closed by fiat plates.

In the past, tractor shovels have been converted to bulldozers (l) by substituting a separate bulldozer blade for the bucket, or (2) by holding the bucket in dumping position, preferably with an hydraulic dump control (see for example U. S. Patent No. 2,413,097, issued to Barker, December 24, 1946), and bulldozers have been converted to tractor shovels (3) by hinging 'the bulldozer moldboard along a transverse axis adjacent the digging edge of the blade and swinging the moldboard back to recumbentposition when it is desired to carry dirt (see U. S. Patent No. 2,303,379, issued December 1, 1942, to G. W. Mark).

These methods have serious drawbacks. The.

bulldozing, projecting side plates, and overhang on the push arms. The third method eliminates the above objections, but introduces new difliculties in that the narrow sideplates of a bulldozer moldboard are inadequate to contain the dirt when the moldboard is used as abucket, and that the fixed pitch of the bottom edge, although suitable for dozing, is improper for digging.

Accordingly it is the principal object of my invention to provide a simple and inexpensive combination bulldozer and tractor shovel that will have all of the advantages and none of the disadvantages of the prior art.

In addition to my principal object, above stated, I have worked out a number of novel and useful details, which will be readily evident as the description progresses.

My invention consists in the novel parts and in the combination and arrangement thereof, which are defined in the appended claims, and of which one embodiment is exemplified in the accompanying drawings, which is hereinafter particularly described and explained.

Throughout the description, the same reference number is applied to the same member or to similar members.

Figure l is a side elevation of a, tractor and combined bulldozer and tractor shovel embodying my invention.

Figure 2 is a plan view of this same tractor and combined bulldozer and tractor shovel.

Figure 3 is anenlarged side elevation partly in section, showing the bucket and associated parts of my invention, in pushing position as a bulldozer.-

Figure 4 is similar to Figure 3, but with the bucket shown in digging position as a tractor shovel.

Referring now to Figures 1 and 2, we see that H is a conventional tractor, mounted on creeping traction units l2, which are pivoted on propelling shaft [3 and have considerable freedom to oscillate independently about said shaft to conform to uneveness of the ground.

Pivoted to eachside of cradle frame I4 on the tractor as at rearward point I5 is a forwardly projecting push arm l6. These arms are connected at their front end by cross beam lid, and serve to support and impel bucket I'I. They are raised and lowered by the following described mechanism. To an intermediate point It on each arm I6 there is pivoted an hydraulic cylinder-piston assembly I9 which is also pivotally supported at a rearward and relatively low point 20 on the cradle frame I. The two cylinders are interconnected and their pistons are actuated by pressure fluid supplied from a conventional hydraulic unit 2| at the front of the tractor.

We now come to the inventive features of my invention, on which see primarily Figures 3 and 4.

Turning to Figures 3 and 4, we see that bucket ll comprises bottom plate 22, and side plates 23.

Bucket side plates 23 are rigidly carried at the ends of cross beam lia by push arms I, and

serve as closures for the ends of the bucket. Push arms l6 and side plates 23 together will sometimes be referred to herein collectively as push means," but other push means could be used without departing from the spirit of my invention.

Bottom plate 22 has along its lower end a digging edge 25 and is hinged to the forward end of side plates 23 for fore-and-aft movement about a transverse axis 28 adjacent digging edge 2!. On the back of bottom plate 22 are brackets 21, for resting engagement with rests 28 on cross 3 beam Ila when the bottom plate is in carrying position. n the back of bottom plate 22 are several vertical reinforcing ribs 20, and at the ends of the bottom plate are cutting shoes 3. for

.use when the bottom plate is raised in dirt-pushing position (Figure 3) On each arm I is mounted an hydraulic cylinder ii, the piston 32 of which is pivotally connected through sliding link 33 and pivot link 24 to one or more ribs 2!. This cylinder II is preferably double-acting, pressure fluid therefor being supplied from hydraulic unit 2|, the details of which are conventional and form no part of my invention.

My invention operates as follows. When push arms II are lowered and pistons 12 are extended, bottom plate 22 is in vertical dirt-pushing position, as shown in full lines in Figure 3, and the machine operates as a bulldozer. It will be noted that when the bottom plate 22 is in this position, its digging edge 2! has the proper steep inclination for bulldozing and that side plates 23 do not project in front of cutting-shoes 32. When pistons 32 are retracted so that bottom plate 22 is recumbent in dirt-carrying position, as shown in Figure 4, the machine operates as a tractor shovel, digging edge 2! now being properly nearly horizontal, and side plates 22 now forming a substantial dirt enclosure with the bottom plate 22. Bucket l1 and push arms I! can be raised by extending cylinder-piston assemblies l0, and then the bucket can be dumped by extending pistons 32 so that bottom plate 22 ejects the load forwardly from the bucket.

Having now described and illustrated one form of my invention, I wish it to be understood that my invention is not to be limited to the specific form or arrangement of parts herein described and shown.

I claim:

1. In a material-handling implement for attachment to a tractor, the combination of: push means attachable to the tractor, and including longitudinal side plates as a rigid part thereof; means, supportable by the tractor, for raising and lowering the push means; a transverse bottom plate, pivotally supported adjacent its for-- ward edge by the push means, the side plates serving as closures for the ends of the bottom plate, to form therewith a dirt-holding bucket when the bottom plate is in recumbent dirt-carrying position; and power-operated means to swing the bottom plate from recumbent dirt-carrying position to upright dirt-pushing position.

2. A material-handling implement according to claim 1, further characterized by the fact that the bottom plate is concave forwardly, and has a transverse digging edge rigid with and swingable with the bottom plate.

3. A material-handling implement according to claim 2, further characterized by the fact that Y the bottom plate is pivoted on the side plates, adjacent their forward edges.

ROBERT L. WELLS.

REFERENCES CITED The following references are of record in the tile of this patent:

UNITED STATES PATENTS Number Name bate 1,690,886 Crombie, Jr. Nov. 6, 1928 2,303,379 Mork Dec. 1, 1942 FOREIGN PATENTS Number Country Date 458,589 Great Britain Nov. '12, 1936