AU2003100832A4 - Cutting apparatus - Google Patents

Description

CUTTING APPARATUS FIELD OF INVENTION This invention relates to an apparatus for cutting irregularly shaped articles into two or more pieces and a process therefor. In particular, this invention relates to a bandsaw apparatus for cutting bones obtained as a by-product of a slaughtering process.

BACKGROUND ART The following description of the prior art is not intended to be, nor should it be interpreted as, an indication of the common general knowledge pertaining to this invention.

Bone cutting bandsaw apparatus have been described in which a vertical exposed bandsaw blade is located intermediate a plane horizontal table top. An operator manually holds the bone with a hand either end and cuts the bone by intersecting same with the bandsaw. The operator pushes the bone toward and into contact with the bandsaw so that the bandsaw intersects and cuts through the bone, normally transverse the longitudinal axis of the bone.

Where the bone is required to be cut into more than two pieces, the operator must carefully re-grip one of the portions first cut by the bandsaw, having returned it to the operator's side of the bandsaw, and pushes the bone through the bandsaw in a second pass to achieve a second cut. By this manual method, bones may be cut into three pieces. This is particularly desirable for dumbbell shaped bone portions, such as the femur of slaughtered cattle where it is desirable to separate the end knuckle portions from the intermediate shaft portion. Such cut pieces are used for human consumption such as in soups and for the production of bone marrow extract.

Manual methods of cutting bones using a bandsaw as described above are inherently hazardous and constitute an unacceptable health and safety risk for the operator. Metal gloves, such as chain mail gloves, cannot be used to provide the manual operator with protection, since they do not guarantee prevention from injury. In fact, such "protective" gear presents an injury risk because of the risk of catching the chain metal on the bandsaw which can lead to the operator's hand being dragged into the saw.

In GB 2089724 there is described a bandsaw for meat and bone. The bandsaw comprises a vertical endless bandsaw mounted intermnediate a table 5, 6 and a finger guard 15 by which an operator may control the passage of the material 19 to be cut without jeopardising the operator's digits. Although the described bandsaw provides some measure of risk reduction for the manual operator, a section of the saw band 4 is still exposed in close proximity to the operator's hands and leaves scope for injury to the operator should the operator be inexperienced, distracted or otherwise lacking concentration.

It is an object of the present invention to ameliorate one or more of the problems discussed in relation to the above prior art or at least to provide a useful alternative thereto.

DISCLOSURE OF THE INVENTION Accordingly, there is provided in one aspect of the invention, an apparatus for cutting irregularly shaped articles (such as bones) into a first portion (such as a centre shank) and one or more remaining portions (such as the knee or upper thigh), the apparatus including: a. a conveyor, which may be an endless belt conveyor, for conveying the first portion from a loading zone, at which an operator introduces the articles to the apparatus, along a corridor through a cutting zone to a delivery zone; b. mounting means (such as a saddle or clamp) supported by the conveyor for securing the first portion as it travels from the loading zone to the delivery zone, the mounting means operative to convey the first portion along the corridor; and c. cutting means spaced away from the loading zone and operative to cut the one or more remaining portions from the first portion, wherein the cutting means is operative in at least one fixed plane which defines at least one side of the corridor.

In another aspect of the invention, there is provided a method for cutting irregularly shaped articles into a first portion and one or more remaining portions, including the steps of: a. conveying a first portion of one of the articles mounted on mounting means from a loading zone along a corridor through a cutting zone to a delivery zone; b. clamping the first portion to the moving mounting mean as the first portion enters the cutting zone; c. cutting the one or more remaining portions of the article from the first portion using a cutting means operable in at least one fixed plane which defines at least one side of the corridor; and d. clearing the remaining portions from the cutting zone by clearing means which follows a cycle in which it is raised on a return pass as it travels counter to the direction of travel of the mounting means and is lowered to clear the remaining portions as it travels in substantially the same direction as the mounting means.

The articles may be of varying shapes and dimensions within specific ranges. For example, the articles may be of the same general shape, and may be axially symmetrical, including shapes such as dumbbell, cylindrical, mushroom, cigar, or may be asymmetrical, such as, for example, rib portions. The articles may be made of polymer, wood, bone or any other article type made of material suitable for working by a saw according to the present invention. In a particularly preferred embodiment, the articles are dumbbell shaped bones stripped of their meat.

The apparatus may comprise a frame for supporting the conveyor. The conveyor may be an endless conveyor. The conveyor may be a driven conveyor. The conveyor may be driven by an electric motor. The corridor may be curved or linear. Preferably, the corridor is linear. Preferably, the conveyor is supported in the frame and the corridor extends horizontally from the loading zone to the delivery zone. However, it will be appreciated by a person skilled in the art that the conveyor may be inclined to the horizontal or may be adapted to travel vertically in the corridor. For example, it may be of advantage in a particular arrangement to utilise the force of gravity in the cutting process, particularly to ensure effective securement of the article during the cutting of same. In the preferred form of the invention, however, the corridor extends in an horizontal orientation.

The conveyor preferably includes an endless belt or chain extending between a pair of rotating wheels or cogs, one of Which is driven whereby to rotate about an axis substantially normal to the longitudinal axis of the corridor immediately adjacent the driven cog or wheel.

The mounting means may positively grip the article. The mounting means may include one or more movable clamping members which secure the first part of the article between the loading zone and the delivery zone and include means for release of the clamping members at the delivery zone. The release means may include a trigger operative to release the clamping members as the mounting rotates over an end cog or wheel. The mounting means may comprise a rest or support means whereby the article is secured in the mounting means by the combined operation of giavity and/or friction between the article and the mounting means. For example, the mounting means may comprise a cradle in which the article may rest by the force of gravity.

The mounting means may include surface gripping means, such as a toothed or other friction surface, to reduce the likelihood of movement of the article relative to the surface of the mounting means once mounted therein or thereon. The mounting means may include a combination of a passive rest or support and one or more clamping members adapted to secure the first part of the article in the rest pre- and post cutting.

The apparatus may further include clamping means.. The clamping means may secure the first part or portion on the mounting means in the cutting zone. The clamping means may comprise a bar aligned along the direction of travel of the mounting means. The clamping means may include one or more clamping bars fixed to the frame independent of the conveyor and adapted to accommodate different sized and shaped articles. The clamping means may be urged towards the article but capable of displacement in response to the shape of the article. The urging means may simply be gravity or may involve a spring or damper.

The clamping means may include compressible spring means (or an equivalent tensile spring arrangement) or may include a damnping means capable of applying a relatively constant pressure to the article irrespective of its dimensions or shape. Preferably, the clamping means includes a single clamp bar suspended from above the conveyor. The clamping means may be adapted to pivot about a transverse axis at one end. The bar may have a curved or angled end. The curved or angled end may be at the end of the bar proximal to the delivery zone. The curved or angled end may extend away from the mounting means. The clamping means may be suspended by a pneumatic arm at its other end.

The mounting means may be fixed to the conveyor. The mounting means may comprise a plurality of individual mounts attached to the conveyor in spaced relationship along its length. Preferably the mounts are spaced whereby the maximum sized article will not interfere with a similarly sized article mounted adjacent thereto on the conveyor.

The loading zone may be an automated area where articles are delivered onto the mounting means in correct orientation ready for cutting. Alternatively, the articles may be placed on the mounting means manually by an operator. The cutting and the loading zones may be separated by a barrier whereby to prevent the operator from accessing the cutting means whilst the cutting means is in operation. The barrier may be deflectable to permit the passage of the articles mounted on the mounting means therethrough. Alternatively, the barrier may be shaped and dimensioned to permit the passage of the articles therethrough by providing a clear entrance defined by the barrier. Preferably, the barrier comprises one or more deflectable doors which effectively impede access of the operator to the cutting zone whilst the cutting means is in operation. In a preferred embodiment, the loading zone is located at one end of the conveyor whereby the mounting means is presented continually to the operator or automatic loading means to permit the placement of articles onto the mounting means as the mounting means completes a turn about the loading zone end of the conveyor. To reduce the clutter and increase the available space immediately surrounding the loading zone, it is preferred that the motor driving the conveyor is located at the opposed end.

The delivery zone may be located at the opposed end of the conveyor to that associated with the loading zone. The delivery zone may comprise separate chutes or receptacles for receiving the different types of cut pieces ready for further processing.

The cutting means may include a single cutting means such as a blade. The cutting means may include a saw band adapted for reciprocating motion. The cutting means may alternatively form part of a continuous saw band such as may be mountable on a pair of spaced wheels, at least one of which is driven. Alternatively, the cutting means may include a circular saw. Preferably, however, the cutting means includes a bandsaw including a continuous saw band. The cutting means may include more than one cutting member. The cutting means may include a pair of spaced cutting members. The pair of spaced cutting members may be part of the same continuous saw band. The pair of cutting members may be adapted to operate in spaced and parallel planes. The pair of cutting members may be adapted to operate on either side of the corridor. Preferably, the cutting means operates in one or more vertical planes. In the case of the cutting means including a pair of cutting members, the pair of cutting members may operate in spaced vertical planes located either side of the corridor and may be effective to cut the article into three pieces.

Where the article is cut into three pieces by the pair of cutting members, the first part may be a central portion of the article which is maintained in mounted relationship with the mounting means beyond the cutting zone through to the delivery zone where it is ultimately despatched. The two end pieces of the article, such as the knuckles of a femur bone, may be permitted to drop to either side of the conveyor and then collected for further processing.

The two end portions may be permitted to drop only as far as a table supported by the frame.

The surface of the table may include a conveying surface for delivery of the end portions to the delivery zone.

Alternatively, the apparatus may further include a clearing means. The clearing means may clear the one or more remaining portions from the cutting zone. The clearing means may include any suitable means for cleaning the end pieces from the table. The clearing means may reciprocatingly travel along a pathway substantially parallel to the direction of travel of the mounting means or substantially adjacent to the mounting means.

The clearing means may be raised on its return pass as it travels counter to the direction of travel of the mounting means, and lowered as it travels in the opposite direction. The clearing means may be adapted to reciprocate back and forth between the cutting zone and the delivery zone whereby to clear the'end portions from the cutting zone through to the delivery zone. The clearing means may be capable of more complex reciprocating movement to avoid interference with the end portions prior to cutting. For example, the clearing means in side elevation may follow a substantially square, rectangular, semicircular or other suitable path.

BRIEF DESCRIPTION OF THE DRAWINGS The invention may be better understood from the following non-limiting description of a preferred embodiment, in which: Figure 1 is a side elevation of the apparatus according to the preferred embodiment of the present invention; and Figure 2 is an end elevation of the apparatus shown in Figure 1.

DETAILED DESCRIPTION OF THE DRAWINGS In Figure 1 there is shown a cutting apparatus 1 including a support base 2, an operational chamber 3, a cutting zone chamber 4 and a frame 9 including a table Mounted on the base 2 intermediate a slot therefor extending the length of the table is a linear conveyor 10. The conveyor 10 is driven by an electric motor 11 located at a rear end of the apparatus 1 corresponding to a delivery zone 6. The motor 11 drives a conveyor wheel 12 in a clockwise direction. Mounted to the frame 5 at the opposite end to the motor 11 is an end idler wheel 13 which completes a continuous loop for a conveyor belt 16 extending between the idler wheel 13 and the driven wheel 12. The conveyor belt 16 is in the form of a series of metal chain links. The linkages are a series of hinged metal plates.

Below the frame 5 and depending therefrom by welded or bolted brackets are a pair of intermediate idler wheels 14 adapted to support the conveyor belt 16 during its passage underneath the frame 5. Fixed by welding to the linkages conveyor belt 16 and equally spaced therealong are mounting means in the formn of a plurality of toothed cradles 15. The cradles 15 are substantially V-shaped in side elevation and comprise a pair of spaced crescent shaped arms 17. An article (not shown) having a substantially cylindrical portion can be stably rested in the cradle 15 as the cradles 15 travel on the top side of the conveyor Located substantially within the cutting zone chamber 4 is a clamping means including a horizontal bar 21 with an upturned end portion 22. The horizontal bar 21 is pivotally mounted at a front end to a downwardly depending support 23, the lowermost point of which is positioned higher than the highest anticipated dimensions of the largest of the articles to be processed whereby the support bracket 23 does not impede the progress or processing of the article. The rear end of the horizontal bar 21 is height-adjustably supported by a downwardly depending pneumatic arnn 25 adapted to apply a constant pressure against objects the articles) which abut against the underside of the horizontal bar 21. The pneumatic ann 25 is pivotally mounted at both ends. The upper end of the pneumatic armn 25 is mounted to a gantry 30 supported above the frame 5. The support bracket 23 is also mounted to the gantry Supported for vertical displacement relative to the gantry 30 is a clearing means 31 which is mounted for both horizontal and vertical movement. The clearing means 31 is operable to reciprocate back and forward along a horizontal track 32 by the driving force of a service motor 33. The horizontal track 32 is mounted for vertical displacement along a vertical column 34 whereby the clearing means 31 is capable of combined vertical and horizontal movement through a rectangular pathway 35 from a side elevation perspective.

The clearing means 31 includes a pair of downwardly depending sweepers 36 adapted to skim the table 5 surface in a rearward direction to remove cut article end pieces which drop onto the table post-cutting.

The apparatus includes cutting means 40 in the form of a pair of bandsaws 41 which each comprise a flexible continuous saw band looped around a pair of upper and lower wheels (not shown) located in the cutting zone chamber 4. Optionally, the pair of saw bands 41 may in fact be a single band with the bandsaw wheels located centrally relative to the longitudinal axis of the conveyor 10 and rotating about axes parallel to that longitudinal axis.

The cutting zone chamber 4 may be in the form of polycarbonate sheeting which restricts operator access whilst the apparatus is operational. Furthermore, the delivery zone chamber 3 may similarly be made from polycarbonate sheeting whereby to provide no visual obstruction for maintenance and operational purposes. The rear end of the delivery zone chamber 3 is open ended to penrmit the removal of cut pieces of the article from the apparatus 1.

The front end of the cutting zone chamber 4 includes a pair of deflectable doors 7 adapted to admit entry of the mounted articles. Optionally, the doors 7 may include a small entrance 8 adapted to admit entry of mounted articles but to impede easy access of the operator to the cutting zone chamber 4 whilst the apparatus 1 is operational.

In use, an operator loads articles to be cut, such as large cattle femur bones 50 onto the cradles 15 which pass through the entrance 8 into the cutting zone chamber 4 where they move under the horizontal bar 21. The horizontal bar 21 is downwardly inclined towards the rear end and is vertically displaced by the article 50 as it moves through the cutting zone chamber 4. The horizontal bar 21 acts as a skid permitting the relatively low frictional passage of the article 50 thereunder whilst applying a predetermined amount of pressure to the article immediately prior and post-cutting to ensure that the article is securely held in place in the cradle 15. Because the horizontal bar 21 is downwardly inclined towards the rear, its rearmost end 22 is upturned to ensure that the centre portion of the article retained on the cradle 15 does not catch or jam at the end of the lowermost point of the horizontal bar 21 as the centre portion exits the cutting zone chamber 4.

As the article 50 engages with the pair of bandsaws 40, the end knuckle pieces of the article 50 are cleanly cut off and fall away to either side of the conveyor 10 onto the table The clearing means 31 continuously or intermittently proceeds through its rectangular route to skim the table surface and to sweep the knuckle portions rearwardly along the table and through the delivery zone 6 to disposal means, such as large containers (not shown) located either side of the conveyor 10 at the rear end of the table 5. The central portion of the article 50 is retained in the cradle 15 beyond the upturned end portion 22 through the delivery zone to the rear end of the conveyor 10 where the central end portion falls out of the cradle 15 under the force of gravity into an awaiting receptacle (not shown) located immediately under the driven wheel 12.

It will be appreciated by those skilled in the art that many modifications and variations may be made to the embodiments described herein without departing from the spirit or scope of the invention.

Throughout the specification the word "comprise" and its derivatives are intended to have an inclusive rather than exclusive meaning unless the context requires otherwise.

Claims (4)

1. An apparatus for cutting irregularly shaped articles into a first portion and one or more remaining portions, said apparatus including: a. a conveyor for conveying said first portion from a loading zone along a corridor through a cutting zone to a delivery zone; b. mounting means supported by said conveyor for securing said first portion as it travels from said loading zone to said delivery zone, said mounting means operative to convey said first portion along said corridor; and c. cutting means spaced away from said loading zone and operative to cut said one or more remaining portions from said first portion, wherein said cutting means is operative in at least one fixed plane which defines at least one side of said corridor.

2. The apparatus according to claim 1, further including: d. clamping means to secure said first portion on said mounting means in said cutting zone.

3. The apparatus according to claim 2, wherein said clamping means comprises a bar aligned along the direction of travel of said mounting means, said bar having a curved or angled end proximal to said delivery zone, said turned end extending away from said mounting means.

4. The apparatus according to any one of the preceding claims, further including: e. clearing means to clear said one or more remaining portions from said cutting zone, wherein: said clearing means reciprocatingly travels along a pathway substantially parallel to the direction of travel of said mounting means or substantially adjacent to said mounting means; and said clearing means is raised on its return pass as it travels counter to the direction of travel of said mounting means. A method for cutting irregularly shaped articles into a first portion and one or more remaining portions, including the steps of: a. conveying a first portion of one of said articles mounted on mounting means from a loading zone along a corridor through a cutting zone to a delivery zone; b. clamping said first portion to said moving mounting mean as said first portion enters said cutting zone; c. cutting the one or more remaining portions of said article from said first portion using a cutting means operable in at least one fixed plane which defines at least one side of said corridor; and d. clearing said remaining portions from said cutting zone by clearing means which follows a cycle in which it is raised on a return pass as it travels counter to the direction of travel of said mounting means and is lowered to clear said remaining portions as it travels in substantially the same direction as the mounting means.