US3795421A

US3795421A - Grapple assembly

Info

Publication number: US3795421A
Application number: US00310265A
Authority: US
Inventors: J Vohl; P Vohl
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-11-29
Filing date: 1972-11-29
Publication date: 1974-03-05
Anticipated expiration: 1991-03-05

Abstract

A grapple assembly arranged to be suspended from a boom, for example on a vehicle to load logs in the forest. A grapple assembly having grapple jaws or buckets and forming a compact slender unit not prone to become obstructed or damaged by surrounding obstacles, positively pivoted around an upright axis and having jaws which can pivot unequally when one is offered a larger resistance than the other upon grappling. A grapple assembly having two grapples pivotally supported by a pivoted linkage arrangement allowing the unequal pivoting thereof, a hydraulic actuator for the grapples and a direction changing drive to pivot the grapples and the actuator about an upright axis.

Description

l n1 Stes aent [1 1 1 9 Vohl et ah Mar. 5, 1974 GRAPPLE ASSEMBLY [76] Inventors: Justin Vohl; Paul-Eugene Vohl, both 'r Examirfer Evon Bhmk of St Marc des Canines Quebec, Assistant Exammer.lohnny D. Cherry Canada 22 Fl (1' N 29 1972 [57] ABST CT 1 1e A grapple assembly arranged to be suspended from a [21] Appl. No.: 310,265 boom, for example on a vehicle to load logs in the forest. A grapple assembly having grapple jaws or buckets and forming a compact slender unit not prone to z gg gg become obstructed or damaged by surrounding obstacles, positively pivoted around an upright axis and [58] Field oi Search 294/88 l 19; having jaws which can pivot unequally when one is offered a larger resistance than the other upon grappling.

[56!] References Cited A grapple assembly having two grapples pivotally supported by a pivoted linkage arrangement allowing the UNITED STATES PATENTS unequal pivoting thereof, a hydraulic actuator for the 3,3l4,709 4/l967 Guinot 294/88 X grapples and a ii -action changing drive to pivot the 3.627.372 l2/l97l Carpenter... 294/88 grapple, and the autumn. almut an upright axia 3,231,303 111966 Tourncau.... 294/88 3,527,495 9/1970 Maradyn 294/88 Ml ClaIms, 7 Drawing Figures PATENTEI] "AR 51974 SHEU 1 OF Q PATENTEDHAR W @5421 SHEET 2 BF &

PATENT MAR 51m SHEET 0F 4 This invention relates to load handling implements and, more particularly, to a grapple assembly of the type adapted to be suspended from a boom.

Grapple assemblies of the above type have proposed mechanisms to open and close the grapples and to positively rotate the latter about an upright axis. Various disadvantages or limitations are noted in the above prior art grapple assemblies. The latter are not adapted to provide unequal pivoting of one grapple relative to the other when a larger resistance is opposed to one grapple upon grappling. The mechanisms for the actuation of the grapples are complex and they are subject to damages and obstructions by environmental elements, such as tree branches.

It is a general object of the invention to provide a grapple assembly which has a relatively slender upright outline to minimize the encumbrance thereof.

It is another general object of the invention to provide a grapple assembly with a linkage arrangement to pivotally support the grapples and arranged to allow unequal pivoting thereof when a larger resistance is encountered by one grapple during grappling.

It is another object of the invention to provide a novel means of positively rotating the grapples about an upright axis whereby to avoid encumbrance by producing a grapple assembly having a relatively slender upright outline to minimize obstructions by environmental elements.

It is another object of the invention to provide a grapple assembly having relatively few exposed moving parts and of simple construction tominimize wear and maintenance of the assembly.

The above and other objects and advantages of the invention will be better understood in the light of the following detailed description, wherein the same reference numeral identifies the same part throughout the various views.

The invention will now be described in detail with reference to a preferred embodiment illustrated, by way of example only, in the accompanying drawings, in which:

FIG. l is a side elevation view of a grapple assembly according to the invention, shown in the fully opened position;

FIG. la is a cross-sectional view as seen along line la la in FIG. 1;

FIG. 2 is a side elevation view of the grapple assembly of FIG. 1 shown in fully closed position.

FIG. 3 is a cross-sectional view as seen along line 3-3 in FIG. 1;

FIG. 4 is a partial elevation view illustrating unequal pivoting of the grapples;

FIG. 5 is a cross-sectional view as seen along line 5-5 in FIG. 1; and

FIG. 6 is a cross-sectional view as seen along line 66 in FIG. 5.

The illustrated grapple assembly basically includes a mounting frame or structure ll rotatably suspended from a direction controlling drive motor 2 to positively change the direction of the mounting structure 1, a suspending connection 3 to fix the assembly to a boom or other supporting structure, lever arms 4 to pivotally support the grapple jaws 5 relative to the mounting structure 1, a pair of actuating links 6 inter-connecting the grapples or jaws 5 together to actuate the latter, a

universal joint structure 7 connected to said two links 6 and a hydraulic actuator 8 adapted to act on the interconnecting links 6 to close and open the grapples 5.

It must be noted that the suspending connection 3, the drive motor 2, the mounting structure l and the hydraulic actuator d are connected one to another into a series extending upright longitudinally of the axis of rotation of the motor 2 and thereby forms a compact and slender arrangement which is thence easier to move around without obstructions.

Referring now particularly to FIGS. ll, 2, and 3, the suspending connection 3 includes a supporting bracket 9 having a forked top end adapted for connection by a pin Ill to a boom, not shown, or other supporting structure. In order to allow for directional control, as will be explained later, the supporting bracket 9 should be restrained against rotation about any upright axis. The lower end of the supporting bracket 9 is hinged by a pin 12 to a lug or ball 13 secured to the top end of the housing 114 of the direction controlling drive motor 2.

The motor 2 is a hydraulic motor of a known type and, therefore, need not be described in details. FIG. 1a schematically illustrates the main elements of the motor 2 which includes an abutment I15 fixed to the housing 14 inside the latter and a piston 16 fixed to a rotor, not shown. The piston 16 drives the rotor under the action of hydraulic fluid on either of the two opposite ends thereof.

The mounting structure, particularly illustrated in FIG. 3, includes a plate 17 fixed to the rotor of the drive motor 2 for rotation therewith about an upright axis. Transverse boards or bars 18 are fixed in pairs edgewise against the underside of the plate 17 and are provided with bores arranged for pivotally mounting pivot pins 19 thereinto in axially aligned relationship on opposite sides of the hydraulic actuator 8. Abutment members 20 are fixed against the underside of the plate 17 and extend therefrom towards the universal joint structure 7, on opposite sides of the hydraulic actuator 8. Side plates 21 are provided to give rigidity to the mounting structure 1.

i The lever arms 4 are arranged in two sets each pivotally suspended by one of the pivot pins W on one of the above-mentioned opposite sides of the hydraulic actuator 8. Each set of lever arms 4 includes two elbowed lever arms i pivotally supported at their upper end by one pivot pin 19 and pivotally connected at their lower end by a transverse pivot 22 to the two grapple jaws 5 respectively. The two sets of lever arms 4! are positioned on opposite sides of the jaws 5.

Each grapple or jaw 5, as best shown in FIG. 3, includes a pair of spaced-apart elongated claw-shaped members 23 retained together by transverse bars 24 welded or otherwise secured thereto. The upper end portion of each claw-shaped member 23 is pivoted by the transverse pin 22.

The actuating links 6 are positioned on opposite sides of the grapples 5 and are pivoted thereto at their opposite ends by two pivot pins 25 extending from side to side of the jaws 5 and parallel to the axes of the

pins

19 and 22. The pivot pins 25 extend through the clawshaped members 23 intermediate the ends thereof and at a distance from the pins 22 whereby to have a lever action about the axis thereof.

As shown in FlGS. 5 and 6, the universal joint 7 includes a rectangular frame having opposite lateral sides 26 extending in spaced relationship longitudinally of the

pivot pins

19,22, and 25 and spacing end walls 27 joining the sides 26 together. Axially aligned pins 28 pivotally mount the above rectangular frame onto the actuating links 6 midway between the pivot pins 25 thereof, and the pivot pin 29 pivotally mounts the above frame relative to the hydraulic actuator 8 in a manner to be hereinafter described. As in all universal joints, the axes of the

pins

28 and 29 intersect each other in this case on the rotation axis defined by the above-mentioned upright axis of directional rotation.

The hydraulic actuator 8 is a hydraulic cylinder unit having a cylinder portion 30 fixed endwise against the undersurface of the plate 17, extending downwardly therefrom and having a piston rod 31 pivotally attached at its free bottom end by a sleeve 32 to the pivot pin 29.

A bottom plate 33 joins the sides 26 of the universal joint 7 to prevent the engagement of obstructions inside the perimeter of the above rectangular frame thereof.

Cooperating L-

shape abutment brackets

34 and 35 are fixed to each end wall 27 of the rectangular frame and to the adjacent actuating links 6 respectively and are arranged to engage each other to thereby limit the pivoting movement of the rectangular frame.

Hydraulic fluid hoses

36 and 37 are connected in any well known and appropriate manner to the hydraulic motor 2 and to the hydraulic cylinder unit 8 respectively.

The

pivots

1 l, 12, 19, and 28 are secured in positions by a screw extending through one of their ends and engaging into an ear or lug of the associated structure.

It is easily understood that the grapples 5 may be directed relative to a load by feeding hydraulic fluid in the proper direction into the motor 2 to cause rotation of the rotor and the grapples suspended therefrom to rotate the required amount about the upright axis of the motor 2. The latter, due to the abutment therein, does allow only about a three-quarter turn in either direction.

The jaws 5 are opened and closed by the extension and contraction respectively of the hydraulic cylinder unit 8 which causes up-and-down displacement of the universal joint structure 7 and lever action of the pivot pins 25, on the jaws 5 about the pins 22. When a higher resistance is encountered by one jaw or grapple 5, the other jaw is allowed by the lever arms 4 and the universal joint 7 to continue its course to complete the closing, as shown in FIG. 4.

It will be readily understood that the grapples 5 may be either of the hook or bucket type without departing from the ambit of the invention which is not to be restricted to the details of construction illustrated and described, but is to be broadly construed as including the changes and alternatives falling within the spirit and scope of the appended claims.

What we claim is:

l. A grapple assembly comprising, in combination, a mounting structure, a first and a second grapple elements, a linkage arrangement including a first pivot pivotally suspending said grapple elements from said mounting structure about a first axis, and a pair of second and third pivots pivotally suspending said grapple elements to said linkage arrangement about spaced parallel transverse axes extending longitudinally of said first axis and allowing unequal pivoting of said grapple elements, actuating link means pivotally connected at spaced-apart points thereof to said first and said second grapple elements, said spaced-apart points being laterally spaced from said second and third axes respectively, power means operatively engaging said mounting structure, and a fourth pivot pivotally connecting said power means to said actuating link means about a fourth axis extending longitudinally of said second and third axes, whereby said power means operatively produces displacement of said link means towards and away from said mounting structure and causes equal and unequal pivoting of said first and said second grapple elements.

2. A grapple assembly as defined in claim 1, wherein said linkage arrangement includes lever arms pivotally connected to said mounting structure by said first pivot, and to said grapple elements by said second and third pivots respectively.

3. A grapple assembly as defined in claim 2, wherein said lever arms include one set of a first and a second lever arms, said first and said second grapple elements form a first and a second elongated jaws each having one inner end portion and an outer end portion, said inner end portions are pivoted onto said first and said second lever arms respectively about said second and third axes, the latter are spaced from said first axis away from said mounting structure, and said actuating link means is pivoted to said elongated grapple jaws intermediate said second and third axes and said outer end portions respectively.

4. A grapple assembly as defined in claim 3, wherein 'said first and said second jaws laterally extend lengthwise of said second and third pivoting axes thereof, said lever arms include another set of a first and a second lever arms pivotally connected to said one inner end portions respectively and to said mounting structure, said one and said another sets of lever arms are positioned on opposite sides of said jaws respectively and said actuating link means includes an actuating link on each of said opposite sides of said jaws and similarly pivotally connected to the latter in spaced-apart relationship to each other.

5. A'grapple assembly as defined in claim 4. further including a universal joint structure secured to said actuating links intermediate the same, said universal joint structure has a first pivot means including said fourth pivot operatively connected to said actuating links, and a second pivot means operatively connected to said power means, said first and said second pivot means are constructed and arranged to allow universal pivoting of said actuating links relative to said power means and said mounting structure.

6. A grapple assembly as defined in claim 5, wherein said power means includes an hydraulic cylinder unit constructed and arranged to displace said universal joint structure and said actuating links towards and away from said mounting structure, whereby to cause pivoting of said jaws towards and away from each other.

7. A grapple assembly as defined in claim 6, further including a direction controlling drive means connected to said mounting structure and constnlcted and arranged to rotate the latter about an upright axis extending transversely relative to said first, second, third, and fourth axes, a suspending device fixed to said direction controlling drive means and arranged to suspend the grapple assembly from a handling structure therefor, said suspending device, said direction controlling drive means, said mounting structure and said hydraulic cylinder unit are serially connected one'to another longitudinally of said upright axis into a compact and slender arrangement operatively standing within the lateral outline of said grapple jaws.

8. A grapple assembly as defined in claim 7, wherein said hydraulic cylinder unit constitutes an hydraulic cylinder coaxially arranged with said upright axis for contraction and extension along the latter.

9. A grapple assembly as defined in claim 7, wherein said direction controlling drive means constitutes an hydraulic motor having a housing connected to said suspending device and arranged to be non-rotatably suspended by the latter, and a rotor coaxially retained into said housing relative to said upright axis and fixed to said mounting structure to cause the rotation of the latter about said upright axis.

10. A grapple assembly as defined in claim 5, wherein said universal joint structure includes a frame pivotally carried by both said first and second pivot means, abutment means is fixed to said mounting structure and extend therefrom towards said frame on opposite sides of said hydraulic cylinder unit and is constructed and arranged to urge said jaws into equally open position upon contraction of said hydraulic cylinder unit.

Claims

1. A grapple assembly comprising, in combination, a mounting structure, a first and a second grapple elements, a linkage arrangement including a first pivot pivotally suspending said grapple elements from said mounting structure about a first axis, and a pair of second and third pivots pivotally suspending said grapple elements to said linkage arrangement about spaced parallel transverse axes extending longitudinally of said first axis and allowing unequal pivoting of said grapple elements, actuating link means pivotally connected at spaced-apart points thereof to said first and said second grapple elements, said spaced-apart points being laterally spaced from said second and third axes respectively, power means operatively engaging said mounting structure, and a fourth pivot pivotally connecting said power means to said actuating link means about a fourth axis extending longitudinally of said second and third axes, whereby said power means operatively produces displacement of said link means towards and away from said mounting structure and causes equal and unequal pivoting of said first and said second grapple elements.

4. A grapple assembly as defined in claim 3, wherein said first and said second jaws laterally extend lengthwise of said second and third pivoting axes thereof, said lever arms include another set of a first and a second lever arms pivotally connected to said one inner end portions respectively and to said mounting structure, said one and said another sets of lever arms are positioned on opposite sides of said jaws respectively and said actuating link means includes an actuating link on each of said opposite sides of said jaws and similarly pivotally connected to the latter in spaced-apart relationship to each other.

5. A grapple assembly as defined in claim 4, further including a universal joint structure secured to said actuating links intermediate the same, said universal joint structure has a first pivot means including said fourth pivot operatively connected to said actuating links, and a second pivot means operatively connected to said power means, said first and said second pivot means are constructed and arranged to allow universal pivoting of said actuating links relative to said power means and said mounting structure.

7. A grapple assembly as defined in claim 6, further including a direction controlling drive means connected to said mounting structure and constructed and arranged to rotate the latter about an upright axis extending transversely relative to said first, second, third, and fourth axes, a suspending device fixed to said direction controlling drive means and arranged to suspend the grapple assembly from a handling structure therefor, said suspending device, said direction controlling drive means, said mounting structure and said hydraulic cylinder unit are serially connected one to another longitudinally of said upright axis into a compact and slender arrangement operatively standing within the lateral outline of said grapple jaws.