US2789711A

US2789711A - Materials handling machine

Info

Publication number: US2789711A
Application number: US292076A
Authority: US
Inventors: Robert E Burrus
Original assignee: Clark Equipment Co
Current assignee: Doosan Bobcat North America Inc
Priority date: 1952-06-06
Filing date: 1952-06-06
Publication date: 1957-04-23
Anticipated expiration: 1974-04-23

Description

April 23, 1957 R. E. BURRUS MATERIALS HANDLING MACHINE 5 Sheds-Sheet 1 Filed June 6, 1952 IN! 'ENTOR. ROBERT E. BURRUS By [m I am 7 AT TYS Apfil23,l957 R E.BURRUS MATERIALS HANDLING MACHINE 5 Sheets-Sheet 2 Filed June 6, 1952 lNwwnmQ ROBERT E.BURRUS ATTYS.

April 23, 1957 R. E. BURRUS MATERIALS HANDLING MACHINE 5 Sheets-Sheet 3 Filed June 6, 1952 INVENTOR. ROBERT E. BURRUS BY a ATTYS.

April 23, 1957 R. E. BURRUS MATERIALS HANDLING MACHINE Filed June's, 1952 5 Sheets-Sheet 4 INVENTOR.

ROBERT E. BURRUS April 23, 1957 R. E. BURRUS 2, 8

. MATERIALS HANDLING MACHINE Filed-June e, 1952 5 Sheets-Sheet 5 I I /44 (x qr JNVEN OR. ROBERT E. BURRUS ATTYS.

MATERIALS HANDLING MACHINE Robert E. Burrus, Buchanan, Mich, assignor to Clark Equipment Company, Buchanan, Mich., a corporation of Michigan Application June 6, 1952, Serial No. 292,076

6 Claims. (Cl. 214-140) My present invention relates to improvements in power actuated shovels, or other load handling devices, adapted for embodiment with vehicles such as industrial trucks or tractors and the like. More specifically, my invention relates to the class of power actuated load handling devices wherein each is disposed at the forward endof a vehicle and may be selectively raised and lowered, and tilted forwardly and rearwardly as conditions of operation require.

It is an object of my present invention to provide a power actuated shovel, or other load handling device, of the general class described wherein a section of the shovel cut by any given horizontal plane may be maintained substantially parallel to the ground during vertical movement of the shovel.

In order to accomplish the above object, I contemplate the provision of parallelogram linkage means pivoted at the rear end to the truck and at the forward end to the shovel. Suitable power actuated means is provided for effecting pivotal movement of the linkage means relative to the truck whereby the shovel may be raised and lowered. As a result of the employment of parallelogram linkage means, a section of the shovel cut by any given horizontal plane will remain substantially parallel to the ground during vertical movement of the shovel. Thus, loads engaged by the shovel while in a lowered position will not be dumped or spilled during raising of the shovel.

It is a further object of my present invention to provide a shovel as described, which may be selectively tilted forwardly and rearwardly.

In the accomplishment of the last noted object, I provide second power actuated means which has connection With the linkage means for shifting a portion of the latter longitudinally to effect pivotal movement of the shovel relative to the ground. It is a feature of my present invention that the second power actuated means comprises a pair of pistons arranged serially and operable independently in a manner permitting the shovel to be positioned positively in either one of three pivotal positions relative to the ground.

It is still another object of my present invention to provide a power actuated shovel, as noted, which is simple in structure, efiicient in operation, and inexpensive to manufacture and repair.

Now, in order to acquaint those skilled in the art with the manner of constructing and using power actuated shovels in accordance with the principles of my present invention, I shall describe in connection with the accompanying drawings a preferred embodiment of my invention.

In the drawings:

Figures 1, 2 and 3 are side elevational views of an industrial truck and the power actuated shovel of my present invention with the latter being shown in various operating positions;

ited States Patent Figure 4 is a plan view of the truck and shovel shown in Figures 1, 2 and 3; and

ice

Figure 5 is an enlarged sectional view of the power actuated means provided for effecting tilting of the shovel.

Referring now to the drawings, there is indicated generally by the reference numeral 10 an industrial truck having forward drive wheels 11 and rear steering wheels 12. The truck 10 is further provided with a hand steering wheel 13 which has connection, through suitable linkage means, with the rear steering wheels 12. Suitable prime mover means (not shown) is provided for driving the forward drive wheels 11.

A shovel or scoop member 14, or other load handling device, is disposed at the forward end of the truck 10 and extends transversely thereof. The shovel 14 preferably has a leading edge 15 for a purpose to be described more fully hereinafter. First arm members 16 extend longitudinally of the truck 10 at each side thereof and are journaled at their forward ends on a shaft 17 carried by spaced flange members 18 secured to the rear end of the shovel 14. The flange members 13 are reinforced by an angle flange 19. The arm members 16, at their rear ends, are suitably secured, as by welding, to sleeve members 20 which are journaled on the ends of a shaft 21 extending transversely of the truck 10.

Pivotal movement of the arm members 16 about the shaft 21 is effected by means of a pair of hydraulic piston and cylinder assembly means indicated generally at 22. The hydraulic assemblies 22 each comprise a cylinder 23 pivoted at the lower end thereof on a shaft 24 extending transversely of the truck 10. The assemblies 22 further comprise piston rods 25 which, at their outer ends, are pivoted about stub shafts 26 carried by bracket members 27 secured to the outer sides of the arm members 16. Fluid is adapted to be admitted into the lower ends of the cylinders 23, through suitable hose lines (not shown) for effecting outward movement of the piston rods 25 and counterclockwise movement of the arm members 16. By bleeding fluid from the lower ends of the cylinders 23, the force supporting the piston rods 25 is removed and the weight of the arm members 16 will cause clockwise movement thereof. The shovel 14 is raised and lowered during pivotal movement of the arm members 16.

I shall now describe the linkage means, and actuating means therefor, by which the shovel 14 may be selectively tilted forwardly and rearwardly. Extending rearwardly from the angle flange 19 at the rear of the shovel 14 are bracket members 36. Pivotally mounted about pins 37, carried at the outer ends of the bracket members 36,

are the forward ends of second arm members 38 which are located above and parallel to the first arm members 16. The rear ends of the second arm members 38 are pivotally mounted on pin members 39 which are each merals 42. The power actuated means 42 each comprise,

as shown in Figure 5, a pair of

cylinders

43 and 44 aligned axially and secured at their adjacentends to a common partition member 45.

Fluid passageways

46 and 47 are formed in the member 45 and communicate, respectively, with the

cylinders

43 and 44. Mounted for movement within the

cylinders

43 and 44, respectively, are

pistons

48 and 49 which are carried at the ends of

piston rods

50 and 51. The

piston rods

50 and 51 extend outwardly of the ends of the

cylinders

43 and 44 and are guided in

cylinder head members

52 and 53. Fluid passageways 54 3 and 55 are formed respectively in the walls of the .

cyljnv ders

43 and 44 at the outer ends thereof. Separate valves (not shown) are provided for controlling the flow of fluid into each .of the cylinders 43. Thus, the

piston rods

50 and 51 may heextended either independently or simulane s y,

The outer ends of the piston rods 50 are pivotally mounted by means of pins 56 to brackets 57 which are secured to the link members 4-0 at the ends of pin members 39. The outer ends of the piston rods 51 are pivotally mounted by means of pin members 53 to the frame of the truck 10. p

In the operation of the power actuated shovel of my present invention, the truck 16 is driven to the location where a load is to be engaged and the shovel 14 positioned in front of the load. Assuming that loose material is to be picked up, fluid under pressure is admitted to the fluid passageways 47 of cylinders 44 so as to extend the piston rods 51. The shovel 14 will assume the position shown in solid lines in Figures 1 and 2. The truck It) is then driven forward causing the leading edge 15 of the shovel 14 to bite into the loose material thus acting as a scoop. After sufficient material has been received in the shovel 14, fluid under pressure is bled from the passageways 47 while fluid under pressure is simultaneously admitted to the passageways 55. The piston rods 51 are thus retracted and the arm members 38 caused to be moved rearwardly. Thereupo-n, the shovel is tilted to the dotdash line position shown in Figures 1 and 2.

The shovel may now be raised for transporting the load by admitting fluid under pressure to the lower ends of the cylinders 23 of the hydraulic assemblies 22. The piston rods 25 are extended to the solid line position shown in Figure 3 while the shovel is disposed in the dot-dash line position of Figure 3. Due to the fact that the shovel 14 is mounted to the truck through parallelogram type linkage, a section of the shovel 14 out by any given horizontal plane will remain substantially parallel to the ground during vertical movement of the shovel 14. Thus, loads engaged by the shovel while in a lowered position will not be dumped or spilled during raising of the shovel.

' At the location where the load is to be deposited, the

piston rods 51 may be extended for tilting the shovel 14 to the solid line position of Figure 3. In this position, a portion only of the contents of the shovel 14 will be dumped. If the entire contents of the shovel 14 are to be dumped, the piston rods 50, together with the piston rods 51, are extended causing the shovel 14 to be pivoted in the position shown in Figure 3 in dashadouble dot mes.

Where the load to be engaged is a relatively hard material such as clay, the piston rods'25, 50 and 51 are fully retracted. The shovel 14 will be disposed in the position shown in dash-dot lines in Figures 1 and 2 with the leading edge 15 offering a cutting edge for hitting into the relatively hard material.

The shovel may be employed as a pusher by extending the

piston rods

50 and 51 fully and the piston rods 25 partially. This position of the shovel 14 is shown in Figure 2 in dash-double dot lines.

Where it is desirable to engage material below the normal ground surface, the

piston rods

50 and 51 are fully extended and the piston rods 25 fully retracted. The leading edge 15 of the shovel 14 is thereupon disposed below the normal ground surface as shown by the dashdouble dot lines in Figure 1.

In view of the fact that the

piston rods

50 and 51 may be retracted and extended either independently or simultaneously, it is to be observed that the shovel 14 may be positioned positively in any one of three operating positions. For example, if the power actuated shovel 14 is in the dash-dot line position of Figure 1, the operator of; the truck may efiiect movement of the shovel to the solid line position by actuating the valve associated with the cylinders .44 for extendin the piston rods 51, If it is desired to move the shovel 14 to the dash-double dot line position, the second valve, associated with the cylinder's 43, is actuated and the piston rods 50 extended. The aforenoted two movements may be combined by actuating both valves at once. Then the

piston rods

50 and 51 will be simultaneously extended and the shovel 14 moved from the dash-dot line position to the dash-double dot line position. In movement of the shovel 14 between its three normal operating positions, no feathering of the valves is required, thus simplifying the operators task of positioning the shovel 14. However, where an intermediate position of the shovel 14 is desired, the valves may be feathered as required.

It will be readily apparent to those skilled in the art that four positive operating positions for the shovel may be readily obtained instead of three, if desired, merely by making

cylinders

43 and 44 and their corresponding piston rods of diiterent lengths. If this is done, one intermediate position may be obtained by fully retracting one of the pistons while the other remains at its extreme outer position, while another intermediate position may be obtained by retracting the second piston while the first one remains at the extreme outer position.

While a materials handling machine equipped with a shovel or scoop is described and illustrated herein, it will be readily understood that the present invention is useful also on materials handling machines equipped with forks or other known load handling devices as well.

Therefore, while I have shown and described what I believe to be a preferred embodiment of my present invention, it will be understood that various modifications and rearrangements may be made therein without departing from the spirit and scope of my invention.

I claim:

1. For use with an industrial truck, the combination of a shovel, first arm means pivoted at one end to the truck and at the otherend to said shovel, first hydraulic piston and cylinder assembly means carried by the truck and having connection with said first arm means for effecting piovtal movement of the latter whereby said shovel may be raised and lowered, second arm means extending parallel to and above said first arm means, said second arm means. atone end being pivoted to said shovel,

' second hydraulic actuating means carried by the truck and having connection with said second arm means for effecting fore and aft movement of the latter whereby said shovel may be pivoted forwardly and rearwardly, and said second hydraulic actuating means comprising a pair of pistons each operable independently between two extreme positions whereby said shovel may be positioned positively in any one of at least three pivotal positions by operating the pistons to selected combinations of their extreme positions.

2. For use with an industrial truck, the combination of a shovel, first forwardly extending arm means pivoted at the rear end to the truck and, at the forward end to said shovel, first hydraulic piston and cylinder assembly means carried by the truck and having connection with said first arm means for effecting pivotal movement of the latter whereby said shovel may be raised and lowered, second arm means extending parallel to and above said first arm means, said second arm means at the forward end being pivoted to said shovel, link means pivotally connected at one end to the rear end of said first arm means and at the other end to the rear end ofsaid second arm means, second hydraulic actuating means carried by the truck and having connection with said link means for effecting pivotal movement of the latter whereby said second arm means may be moved fore and aft and said shovel pivoted forwardly and. rearwardly, and said second hydraulic actuating means comprising a pair of pistons arranged coaxially and. operable. independently whereby said shovel may be positioned positively in. any one of three pivotal positions at completion of piston travel.

3. For use with an industrial truck, the combination of a shovel, arm means pivoted at one end to the truck and at the other end to said shovel, power actuated means carried by the truck and having connection with said arm means for efiecting pivotal movement of the latter whereby said shovel may be raised or lowered, hydraulic actuating means carried by the truck, linkage means between said hydraulic actuating means and said shovel whereby upon actuation of said hydraulic actuating means said shovelmay be tilted forwardly and rearwardly, and said hydraulic actuating means comprising a pair of pistons arranged for operation independently each between two extreme positions whereby said shovel may be positioned positively in any one of three pivotal positions at completion of piston travel.

4. For use with a vehicle having a load handling device carried thereby and power actuated meansjcarried by the vehicle and having connection with the load handling device for raising and lowering the latter, the combination of hydraulic actuating means carried by the vehicle and having separate connection with the load handling device for tilting the latter forwardly and rearwardly, and said hydraulic actuating means comprising a pair of pistons operable independently each between two extreme positions for positioning positively the shovel in any one of three pivotal positions corresponding to three combinations of extreme positions of the pistons.

5. A positioning mechanism for a load handling device mounted on arm means carried by a vehicle, comprising linkage means connected to the load handling device and the arms, and hydraulic actuating means connected to the said linkage, said hydraulic actuating means comprising a pair of independently operable axially aligned pistons each operable between two extreme positions for positively positioning the load handling device in two extreme positions and at least one intermediate position.

6. A positioning mechanism for a shovel mounted on power actuated elevatable arms carried by a vehicle, com prising linkage means connected to the shovel and the arms, and hydraulic actuating means connected to the said linkage for moving the shovel, said hydraulic actuating means comprising a pair of axially aligned pistons, said pistons being independently operable whereby when both said pistons are at their innermost positions the shovel is positively positioned in one extreme position, and when the said pistons are both located at their outermost positions the shovel is positively positioned in the other extreme position, and when one piston is at its innermost position and the other at its outermost position the shovel is positively positioned in a position intermediate of the said extreme positions.

References Cited in the file of this patent UNITED STATES PATENTS 254,741 Walsh Mar. 7, 1882 947,964 Collins Feb. 1, 1910 2,304,443 Butler Dec. 8, 1942 2,348,899 Guidnard et al May 16, 1944 2,483,239 Sharpe Sept. 27, 1949 2,658,635 Nelson Nov. 10, 1953 2,668,631 Reese Feb. 9, 1954 2,678,741 Pilch May 18, 1954