US3899094A

US3899094A - Material handling apparatus

Info

Publication number: US3899094A
Application number: US422079A
Authority: US
Inventors: John Charles Youl
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-12-06
Filing date: 1973-12-05
Publication date: 1975-08-12
Anticipated expiration: 1992-08-12
Also published as: GB1455462A

Abstract

This invention relates to apparatus for handling material of a solid nature, and particularly long and/or heavy sections of material that are difficult to manoeuvre without mechanical assistance. One application of the invention is in relation to the transport or manoeuvring of logs within forest areas, or within areas at which logs are stored for subsequent treatment.

Description

United States Patent [191 Youl [4 1 Aug. 12, 1975 I MATERIAL HANDLING APPARATUS [76] Inventor: John Charles Youl, Symmons Plains,

Perth, Tasmania, Australia [22] Filed: Dec. 5, 1973 [21] Appl. No.: 422,079

[30] Foreign Application Priority Data Dec. 6, 1972 Australia 1509/72 [52] US. Cl 214/147 G; 294/106 [51] Int. Cl. B66c 1/62 [58] Field of Search 214/147 G, 147 R, 92;

[56] References Cited UNITED STATES PATENTS 2,684,166 7/1954 Jarnett 294/88 X 3,477,596 11/1969 Michaelson 214/147 G X FOREIGN PATENTS OR APPLICATIONS 536,048 1/1957 Canada 294/88 Primary E.\'aminerRobert J Spar I Assistant ExaminerGeorge F. Abraham 5 7 ABSTRACT This invention relates to apparatus for handling material of a solid nature, and particularly long and/or heavy sections of material that are difficult to manoeuvre without mechanical assistance. One application of the invention is in relation to the transport or manoeuvring of logs within forest areas, or within areas at which logs are stored for subsequent treatment.

8 Claims, 10 Drawing Figures PATENTEU 2i975 3.899094 SHEET 1 FIG I PATENTED AUG 1 2 975 SHEET MATERIAL HANDLING APPARATUS BREIF DESCRIPTION OF THE INVENTION 1. Prior Art Manipulation of logs can be an extremely difficult task, especially in confined areas, and mechanical aids used prior to this invention have usually been of relatively crude and not particularly effective construction. For example, one commonly employed method involves attachment of a chain between the log and a tractor or other motorized vehicle, and the log is dragged by the vehicle in such a way that its leading end tends to gouge into the ground.

SUMMARY OF THE INVENTION It is a principal object of the present invention to provide material handling apparatus which is of effective construction and enables convenient manipulation of relatively heavy objects such as large logs, even within confined areas.

Apparatus in accordance with the invention is adapted for attachment to a tractor or other prime mover, and as a matter of convenience the term tractor will be hereinafter used as a generic term for all suitable prime movers or motorized vehicles. The apparatus may be arranged for direct mounting on the tractor, or it may include a wheeled frame which is con nectable to the tractor through an appropriate coupling. Example embodiments of both types of construction will be hereinafter described.

According to the present invention, there is provided material handling apparatus including, a support frame attachable to a vehicle or prime-mover, a jaw assembly including two gripping jaws arranged for relative movement towards and away from each other, actuating means operable to cause relative movement of said jaws, mounting means connecting said jaw assembly to said frame to permit movement of said assembly relative to said frame, said jaws depending from said mounting means to receive material therebetween, and restraining means connecting a lower part of said jaw assembly to said frame so as to limit movement of said assembly relative to said frame.

The following description refers in more detail to these essential features and further optional features of the invention. To facilitate an understanding of the invention, reference is made to the accompanying drawings where these features are illustrated in preferred form. It is to be understood however, that the essential and optional features of the invention are not limited to the specific forms of these features as shown in the drawings.

THE DRAWINGS In the drawings:

FIG. 1 is a semi-diagrammatic side elevational view of one embodiment of the invention adapted for direct attachment to a tractor or other vehicle;

FIG. 2 is an end view of the embodiment shown in FIG. I;

FIG. 3 is a plan view of the embodiment shown in FIG. 1;

FIG. 4 is an end view of the jaw assembly of the FIG. 1 embodiment, viewed from the left hand side of FIG. 1, parts being omitted for convenience of illustration;

FIG. 5 is a view similar to FIG. 4 but showing the jaw: in a partially closed position about a log;

FIG. 6 is a view on a reduced scale taken along line 66 of FIG. 4;

FIG. 7 is a view on a reduced scale taken along line 77 of FIG. 4;

FIG. 8 is a plan view of an alternative embodiment 01 the invention in which the jaw assembly is mounted or. a wheeled chassis or base frame;

FIGv 9 is a cross-sectional view taken along line 99 of FIG. 8; and

FIG. 10 is a side elevational view of the FIG. 8 embodiment showing the jaw assembly in a raised position, parts being omitted for convenience of illustration.

DETAILED DESCRIPTION Referring now to the drawings:

A feature of the apparatus is that it includes a jaw assembly 2 comprising at least two gripping jaws 3 which are interconnected for relative movement so as to releasbly grip an object such as a log therebetween, and are mounted on a support frame or unit 4 in such a way as to be capable of some movement relative to that frame or unit during transport or manipulation of a log. The support frame or unit 4 is connectable to a tractor in a manner such as to permit controlled raising and lowering of the jaw assembly 2 relative to the ground. Further features of the invention will become apparent from the following detailed description of preferred embodiments.

Referring in particular to the embodiment of FIGS. 1 to 7, the jaws 3 are curved and arranged so as to have respective inner concave surfaces 5 in opposed relationship. In the operative position of the jaws 3, they depend from their mounting 6 with the support frame 4, and that mounting 6 includes a hookes joint, or other suitable coupling which permits substantially universal movement of the jaw assembly 2 relative to the support frame 4. The jaws 3 are pivotally connected by pin 7 (see FIG. 2) so as to permit relative movement towards and away from each other, and that movement is controlled through actuating means 8 as hereinafter described. If desired each jaw may swing about a separate pivot rather than the common pin 7, or relative movement other than pivotal movement may be employed.

Each jaw 3 of the illustrated embodiment is formed of a blade section 9 and a backing flange or rim section 11 which defines the outer surface of the jaw 3. The blade section 9 extends inwardly from the rim section 11 so that one edge defines the inner concave surface 5 of the jaw 3, and that edge may be formed to assist in obtaining a firm grip on a log. For example, each blade edge 5 may slope as at 12 (see FIGS. 4 to 7), outwardly and rearwardly relative to the intended direction of travel of the apparatus, and thereby enable the jaws 3 to bite into a log.

It is further preferred that there is some overlap between the blade sections 9 of the jaws 3 in the fully closed position of the jaw assembly 2, so as to permit logs of relatively small cross-sectional shape to be gripped therebetween. Such overlapping may be achieved in several ways, such as by providing a slot or recess in the lower portion of each rim section 11, which slot or recess is disposed and shaped to receive part of the blade section 9 of the other jaw. The arrangement should be such that the blade sections 9 lie in close proximity in the fully closed position so as to avoid any tendency for the jaws to twist a log gripped therebetween. In the particular construction shown in the drawings however, such overlap is achieved by providing one of the jaws 3 with two laterally spaced blades 9 (see FIG. 7) as that the blade 9 of the other jaw 3 can enter into the gap 13 between those two blades.

The support frame 4 of the example directly mounted version of the apparatus, shown in FIGS. 1 to 3 includes a post member 14 adapted to be attached to a tractor in a substantially upright position and having the jaw assembly 2 mounting at or adjacent its upper end. If the tractor includes a three point linkage type coupling system, it is generally convenient to arrange the support post 14 for attachment to that system. In the embodiment shown, the lower end portion of the post 14 is secured to an intermediate portion of a cross member 15 which is connectable at its opposite end portions to the lower links of the tractor coupling (not shown). The upper link of the coupling is connected with an intermediate portion 17 of the support post 14 through any suitable means. If desired, the support frame 4 can be strengthened by brace members 18 extending between the outer end portions of the cross member 15 and the upper end portion of the post 14.

The cross member 15 is connected to the lower links through a pair of coupling arms 19, each of which is rigidly secured to the cross member 15 at or adjacent a respective end thereof and extends rearwardly from that member. The end of each arm 19 remote from the cross member is pivotal by or otherwise connectable to a respective link of the tractor coupling. If the frame 4 is to be connected to the lower links only of the tractor coupling, the opposite end portions of the cross member 15 may be attached to or cooperate with those lower links to prevent or limit relative movement between those links and the coupling arms 19. For example, the end portions of the cross member 15 may be recessed so as to locate about the respective lower links of the tractor coupling. Provision of the coupling arms 19 provides a clearance space between the cross member 15 and the jaws 3 so as to minimize fouling between the cross member 15 and a log held by the jaws 3.

With the arrangement described, the upper end of the post 14, and consequently the jaw assembly 2, can be moved towards and away from the ground by appro priate actuation of the three point linkage system of the tractor. Although the post member 14 has been described as substantially upright in the operative posi tion, it will be seen from FIG. 1 of the drawings that it actually slopes upwardly and rearwardly of the tractor, even in the fully raised position of the apparatus, so as to effectively position the jaw assembly 2 rearwardly of the tractor and provide end clearance for a log.

As previously mentioned, the mounting 6 between the jaw assembly 2 and the support post 14 preferably includes a universal coupling. In the particular form shown, that coupling includes two yokes 21 and 22 and pivotally connected through a block 23 so that there are two axes of rotation defined by

pins

24 and 25 respectively. Pin 24 extends substantially upright, and pin 25 extends generally transverse to both the pin 24 and the jaw pivot pin 7. The yoke 21 is secured to the support post 14 whereas the yoke 22 is secured to the jaw pivot pin 7 or a member attached to that pin. Such an 4 arrangement permits the jaw assembly 2 to adopt a large number of positions relative to the support frame 4 during use, and thereby minimizes strain on the apparatus during manipulation of heavy logs.

Restraining means is provided to limit rearward movement of the lower part of the jaw assembly 2 relative to the support frame 4 and in the preferred construction shown that means includes a chain 26 having its opposite ends secured to a respective jaw 3 as at

positions

27 and 28, and being engaged intermediate its ends by an abutment secured to the support frame 4. In the illustrated embodiment the abutment includes two rollers or sheaves 29 positioned adjacent respective opposite ends of the cross member 15 and being freely rotatable so that the chain 26 can move relative to the frame 4 to adapt to changes in the jaw assembly position. It will be appreciated that another flexible, but relatively non-extensible, element such as a cable or rope may be substituted for the chain. The sheaves 29 are preferably mounted so as to be capable of limited axial movement to allow for changes in the disposition of the chain 26 brought about by raising and lowering of the jaw assembly 2. In the illustrated embodiment such a mounting includes a pivot pin 3 on which the sheave 29 is mounted, and a bracket 32 secured to the cross member 15 so as to overlie the sheave 29 with sufficient clearance to permit the desired axial movement.

It is also preferred to provide biasing means whereby the jaw assembly 2 is urged into a normal rest position in which it is adapted for ready engagement with a log. Such means is illustrated as including two helical tension springs 33 each extending between an intermediate portion of a respective one of the brace members 18 and an outer end of a control arm 34 extending from and connected to the jaw assembly 2. In the embodiment shown, the control arm 34 is rigidly connected to the jaw pivot pin 7 or a member such as a boss secured to that pin.

Actuating means for the jaw assembly may take any suitable form, but hydraulic actuation is generally found convenient. In the preferred arrangement shown, an actuating arm 35 extends upwardly from the upper end of each jaw 3 and is rigidly secured to the respective blade or blades 9. Each actuating arm 35 extends angularly upwardly and outwardly so that it and the associated jaw 3 are both disposed on the same side of the support post 14, but on different sides of the assembly pivot 7. A double-acting hydraulic piston cylinder assembly 8 connects the outer ends of the actuating arms 35 and is connectable to the hydraulic system of the associated tractor so as to be operable to cause relative movement of the jaws 3 about their pivot 7. An arrangement of this kind permits the application of extremely high pressures between the jaws 3 so that the apparatus is capable of firmly gripping and moving logs of large size. It will be appreciated that when a large log is located within the jaw assembly 2, the actuating arms 35 will be closer together than in the case of a relatively small log, and as a result the length of the lever arm between the pivot 7 and the piston-cylinder assembly 8 is greater than in the last mentioned case. Thus, the force applied to a log by the jaws 3 is automatically regulated according to the size of that log.

An example wheeled frame" version of the apparatus is shown in FIGS. 8 to 10 of the drawings, in which construction the support frame 4 is carried by a base frame or chassis 36 which is mounted on ground engaging wheels 37 located adjacent to a rear end of the chassis, and is connectable at its front end 38 to the three point linkage system of a tractor, or to other mechanism operable to cause up and down movement of that end. The cross member 15 of the support frame 4 extends between and is pivotally connected to laterally spaced side members 39 of the chassis 36 so that the support frame 4 can swing relative to the chassis 36 about an axis extending substantially parallel to that of the ground engaging wheels 37. That pivotal connection is located intermediate the front and rear ends of the chassis 36, and a drawbar 51 extends fowardly from the support frame 4 for connection to a ball coupling or other coupling means provided on the tractor. Preferably, the drawbar 41 is rigidly secured to the cross member 15 of the support frame 4.

With the foregoing arrangement, the jaw assembly 2 is raised and lowered by up and down movement of the front end 38 of the chassis 36, since the ground engaging wheels 37 act as a fulcrum and the front end 42 of the drawbar 41 is held relatively stationary by its connection to the tractor. In addition, the lift provided by the tractor mechanism is magnified at the jaw assembly 2 because of the lever system defined by the construction described. That is, there is in effect a double-lift as follows:

a. When the front end 38 of the chassis is raised as shown in FIG. the position of the cross member relative to the ground is altered, so effecting a first lift.

b. As the cross member 15 rises, the angular disposition of the drawbar 41 relative to the ground alters because of the stationary connection at the front end of that bar, and consequently the support post 14 is swung rearwardly about the cross member pivot, thereby effecting a second lift of the jaw assembly 2.

The wheeled frame version illustrated is further modified over the embodiment first described in that the support post 14 has an upright lower section 43 and a rearwardly extending upper section 44. In addition, the biasing means includes three helical tension springs one of which, 45, extends between the control arm and the support post 14, and the other two, 46, each extending from the support post 14 to an intermediate portion of a respective one of the jaw actuating arms 35.

In each of the embodiments described, the biasing springs serve the dual purpose of centralizing the jaw assembly 2 about the universal joint 6 relative to the intended direction of travel, and also maintaining tension in the restraining chain 26. In the last described embodiment however, the spring 45 provides the principal source of tension for the chain 26.

Apparatus as described provides extremely effective means for handling logs and other objects, and in practice it is found that such apparatus causes less fatigue to operators than prior conventional apparatus of the same general type. The apparatus enables secure clamping of relatively large and small logs, and is constructed in such a way that minimum strain is imposed on the apparatus and associated machinery during manipulation of logs.

Finally, it is to be understood that various alterations, modification, and/or additions may be introduced into the constructions and arrangements of parts previously described without'departing from the spirit or ambit of the invention as defined by the appended claims.

1 claim:

1. Material handling apparatus including: a support frame attachable to a vehicle or prime-mover; a jaw assembly comprising two gripping jaws which are pivotally connected for relative movement towards and away from each other; each said jaw having a blade section which is curved so as to define an inner concave surface arranged in opposed relationship to the corresponding surface of the other said blade section, and an arm rigidly secured to said blade section and extending away therefrom, each said arm and associated blade section being located on the opposite sides respectively of said jaw pivot; actuating means connected between said jaw arms and being operable to cause relative pivotal movement of said jaws; mounting means connecting said jaw assembly to said frame to permit movement of said assembly relative to said frame about at least two axes, one of which extends substantially upright and is transverse to the other of said axes; and flexible restraining means interconnecting said blade sections and mounted to freely move around a portion of said frame so as to limit movement of said jaw assembly to said frame in one direction about the other of said axes of said mounting means while allowing free movement of the jaw assembly about the one axis in both directions.

2. Apparatus according to claim 1, wherein each said jaw arm extends angularly relative to the associated jaw blade section, the arrangement being such that movement of said arms away from each other causes movement of said blade sections towards one another, and the distance between said actuating means and said jaw pivot increases as the blade sections separate thereby providing an increased mechanical advantage for application of a clamping force by said blade sections.

3. Apparatus according to claim 1 wherein said actuating means includes a pressure fluid piston-cylinder assembly having opposite ends portions connected to a respective one of said jaw arms.

4. Apparatus according to claim 3, wherein said support frame includes a post member which is connected to and extends upwardly from a cross member and is connected to said jaw assembly through said mounting means at an upper end portion, and said frame is connectable to a said vehicle or prime-mover at a lower end portion thereof.

5. Apparatus according to claim 4, wherein the lower end portion of said frame is constructed for direct connection to a three-point linkage system of a tractor.

6. Apparatus according to claim 4, wherein said cross member is pivotally connected to a base frame for movement relative thereto about an axis extending substantially parallel to said one axis of said mounting means axes; said base frame having ground engaging wheels attached thereto adjacent a rear end thereof, and means for attachment to lifting mechanism of a vehicle or a prime-mover adjacent a front end thereof; said cross member pivot being located intermediate said front and rear ends of the base frame; and a drawbar is secured to said support frame to extend forwardly thereof and is arranged for attachment to a trailer coupling of said vehicle or prime-mover.

7. Apparatus according to claim 6, wherein biasing means extends between said support frame and said jaw assembly to resist relative movement of said jaw assembly and urge that assembly into a normal raised position.

8. Apparatus according to claim 7, wherein said restraining means includes a flexible but substantially intermediate section cooperating with abutment means connected to said support frame so that lengthwise movement of said element is permitted but lateral movement of said intermediate section is resisted in at non-extensible elongated element having opposite ends least one direction.

secured to a respective one of said jaws, and having an

Claims

8. Apparatus according to claim 7, wherein said restraining means includes a flexible but substantially non-extensible elongated element having opposite ends secured to a respective one of said jaws, and having an intermediate section cooperating with abutment means connected to said support frame so that lengthwise movement of said element is permitted but lateral movement of said intermediate section is resisted in at least one direction.