GB2225924A

GB2225924A - Plucking device

Info

Publication number: GB2225924A
Application number: GB8925860A
Authority: GB
Inventors: Timothy Denham Smith
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-11-15
Filing date: 1989-11-15
Publication date: 1990-06-20
Also published as: GB8925860D0; GB8826671D0

Abstract

A portable plucking device for removing feathers from the carcass of a bird, which device comprises: a. a pair of generally cylindrical rotatable roller members 1, 2 having their longitudinal axes substantially parallel to one another and spaced apart so as to provide a nip gap 10 between the opposed surfaces of the roller members, the nip gap being adapted to receive a feather and to grip the stem of the feather between the opposed surfaces of the roller members so as to apply axial tension to the feather as the roller members rotate; b. means 4 located at or adjacent one end, preferably said first end, of the said roller members for rotating at least one of the roller members about its longitudinal axis; c. guide means 20 preferably a power drill; and located at the other end of said roller members for guiding the stem of a feather into the nip gap between the roller members. <IMAGE>

Description

TITLE: PLUCKING DEVICE The present invention relates to a plucking device, notably to a hand held machine for plucking chickens, turkeys and other poultry and game birds.

BACKGROUND TO THE INVENTION: Large scale machines exist for plucking poultry on a commercial scale, which machines comprise rotating drums carrying rubber or similar fingers or flails which strip feathers from poultry carcasses passed between two such drums which are contra-rotated due to the frictional contact between the flails or fingers dragging across the feather cover of the carcass. Such machines are both large and expensive and find use only in large scale commercial operations where their cost and size can be accepted.

Where single birds are to be plucked, this at present has to be done manually, which is often distasteful to the housewife. Furthermore, where a small number of birds are to be plucked, for example on a small scale poultry farm, this also often has to be done by hand. It has been proposed to provide a small scale version of the rotating flail arm type plucking machines used in large scale operations, but these are cumbersome and for safety reasons must be fixedly mounted, thus limiting their use.

I have devised a hand held plucking device which provides a simple and effective mechanical means whereby poultry and game birds can be plucked on an individual basis or on a small commercial scale.

SUMMARY OF THE INVENTION: Accordingly, the present invention provides a hand portable plucking device for removing feathers from the carcass of a bird, which device comprises: a. a pair of generally cylindrical rotatable roller members having their longitudinal axes substantially parallel to one another and spaced apart so as to provide a nip gap between the opposed surfaces of the roller members, the nip gap being adapted to receive a feather and to grip the stem of the feather between the opposed surfaces of the roller members so as to apply axial tension to the feather as the roller members rotate; b. means located at or adjacent one end of the said roller members for rotating at least one of the roller members about its longitudinal axis; and c. guide means located at the other end of said roller members for guiding the stem of a feather into the nip gap between the roller members.

Preferably, the effective length of the nip gap between the roller members is less than 5 cms to assist manoeuvrability of the roller members through the feather cover of the carcass. This can be achieved by the use of suitably short roller members or by providing a shielding member extending axially along at least part of the roller members and restricting access to the nip gap.

Accordingly, the invention further provides a device of the invention having a member extending from the said one end of the said roller members to a point intermediate the ends of the roller members for restricting access to the nip gap.

Preferably, the shielding means extends to from 2 to 5 cms of the free end of the rollers and carries a forked guide means which extends beyond the free ends of the roller members to guide the stem of a feather into the nip gap between the rollers.

The means for rotating the rollers can be an electric, pneumatic or other motor to which the roller members are permanently attached and from which they are driven directly or via a suitable gearing or the like. However, it is particularly preferred that the roller members are mounted on a housing, optionally containing drive gearing, which is demountably attachable to a pneumatic or electric motive power source, such as a hand held rotary drill or the like, or via a flexible drive cable to a remote motive power source. In this way, the invention provides an attachment which can readily be fitted to a conventional power tool.

The roller members for use in the invention are to grip the stem of a feather entering the nip gap between them. The nip gap is therefore selected to apply sufficient grip to the stem to ensure that it is carried with the opposing surfaces of the roller members as they rotate. Typically, the nip gap is no more than 1 to 2 mms, since feather stems can be readily compressed. However, the gap can be made adjustable to suit different thickness of stem, for example for fine breast feathers as opposed to coarse wing pinion feathers.This can be achieved in a number of ways, for example, drive shafts carrying the roller members can be mounted on radially adjustable bearings or the bearings can be mounted in radial slides to permit radial movement of the roller members, the bearings being urged together by tension or compression springs so that the nip gap will automatically vary to accommodate a range of stem thicknesses. Alternatively, the roller members can be of interchangable diameters to vary the nip gap.

The roller members desirably have a high friction or gripping surface to reduce slip between the roller members and the feather stems. This can be achieved by forming either or both rollers with axial ribs or grooves which localise the grip of that roller on the stem, for example by forming one roller wtth axial ribs or flutes having a blunt apex to reduce the risk of severing the stem.

Alternatively, the desired surface can be provided by mounting a sleeve of an appropriate high friction material on a metal drive shaft. In a particularly preferred form of the device, one roller is formed as a fluted or polygonal cross-section roller, the other roller member being a rubber sleeve mounted on a steel drive shaft. If desired, the rubber sleeve can have a similar polygonal cross-section or can have axial grooves or flutes which cooperate with those on the polygonal roller, for example by registering therewith, so that the grip on the stem is localised at the point of contact between the crowns of the cross-section of the roller members or of the axial flutes.

Alternatively, the crowns or flutes on the two roller members can be out of register so that the stem is crimped or held between the opposing crowns and flutes on the opposing faces of the roller members.

The rollers can be made from rigid materials, for example a metal such as a steel. However, it is preferred that at least one of the roller members have a resilient surface formed from a hard rubber or plastic having a high friction surface. For example, a metal shaft can carry a sleeve having a plurality of flexible or semi-rigid radial ribs, knobs or fingers which grip the stem of a feather against the anvil or plattern effect of the opposed face of the other roller. In such a case the nip gap can be merely a clearance gap between the opposed surfaces of the roller members.

As stated above, the nip gap between the roller members has a limited effective axial length. The term effective length is used herein to denote that length of the nip gap within which the stem of a feather can penetrate. As explained below, it is preferred that the stem should have access to only a limited length of the total nip gap and this is preferably achieved by the presence of the shielding member. We have found that this reduction in the effective length of the nip gap is important if adequate manual directional control of the free ends of the roller members is to be readily achieved. If an excessively extended nip gap is used, additional feathers may be drawn into the upper portion of the nip gap as well as those feathers being fed into the nip gap adjacent the operative end of the roller members.The roller members may snatch at those additional feathers and drag the roller members into the feather covering where further feathers may enter the nip gap aggravating the problem. This results in erratic directional control of the device. By limiting the effective axial length of the nip gap to less than about 5 cms, this problem is reduced.

It is also desirable for the operative end of the roller members to be located closely adjacent to and generally parallel to the skin of the carcass in use, so that the thickest and strongest portion of the stems of the feathers is gripped in the nip gap, so that the pull applied to the stems is generally normal to the face of the carcass so that possible damage to the skin of the carcass is reduced.

Where short roller members are used, this can be achieved by mounting the roller members terminally on an elongated housing containing the shafts or other drive means by which the roller members are driven from the motor or power tool.

Preferably, such roller members are mounted with their longitudinal axes at an angle to that of the housing, for example at from 10 to 450 thereto, to assist maneouvreability of the device within the feather covering.

Alternatively, where longer roller members, e.g. from 5 to 15 cms long, are used, they are housed in a shielding member which restricts the effective length of the nip gap to that terminal portion adjacent the free end of the roller members so that feathers enter the nip gap only in the terminal portion. The shielding member can take the form of a generally cylindrical housing surrounding the drive shafts and/or part of the length of the roller members so as to leave the desired length, say 2 to 3 cms, of the roller members and the nip gap between them exposed at the free end of the housing. Alternatively, the shielding member need not extend wholly around the roller members but can take the form of a semi-circular or similar cover extending over that side of the roller members to be adjacent the feather covering of the carcass.The shielding member can thus be formed as a partial or total extension of the gearbox or motor housing of the device and can be made from a metal or other suitable material.

The device is also provided with means for guiding the stems of the feathers to be plucked into the nip between the free ends of the roller members. The guide can take the form of a conical or other tapered extension of the roller members. However, it is preferred to provide a static fork-like guide member carried at the operative end of the shielding member or housing and extending axially beyond the free end of the nip gap. A typical guide means comprises a two pronged fork member having its tines extending axially forward of the free end of the roller members and with the tines splayed to guide the stems into the nip gap between the roller members. The guide member can be formed as an integral part of the shielding member or housing or can be a separate interchangable component, for example a flat metal fork bolted, welded or otherwise secured to the shielding member or housing.It is also preferred that the tips of the tines of the guide member be upturned to reduce the risk that they will snag on the skin of the carcass.

As stated above, the device is conveniently formed as an attachment to a power drill or the like, in which case the roller members will be mounted on a housing capable of being mounted on the power tool housing and containing gearing and shafts necessary to transmit the drive from the power tool to one or both of the roller members and to rotate the roller members at the desired speed. The optimum speed will vary according to the type of bird and the area of the bird which is to be plucked. The variation in speed of rotation may be achieved by use of the variable gearing or variable speed control on the power tool itself or by providing alternative gear ratios within the gearing of the device itself. In general it is preferred that the roller members have a diameter of from 1 to 5 cms, notably about 2 to 3 cms, and that they are rotated at from 1500 to 4000 R.P.M.

The device of the invention provides a simple and effective hand portable means for plucking a wide range of birds and can be used domestically or can be used on a small commercial scale. In the latter case, the device may be provide with an air driven motor fed from a common compressed air line and several devices with different nip gaps and speeds of operation can be used in series so as to pluck different areas of the bird carcasses. Alternatively, the devices can be driven from a common or remote power source by means of flexible drive cables, thus reducing the weight of the device itself which has to be handled by an operator.

The invention also provides a method for removing feathers from the carcass of a bird, which method comprises passing a device of the invention over the carcess with its operative end within the feather covering of the carcass whereby the stems of feathers are guided into the nip gap between the rotating roller members of the device whereby the stems of the feathers are gripped by the surface of one or both rotating roller members so as to apply axial tension to the stem and withdraw it from the carcass.

DESCRIPTION OF THE DRAWINGS: The device of the invention will now be described by way of illustration only and with respect to the accompanying drawings in which Figure 1 is a diagrammatic plan view of the device; Figure 2 is a diagrammatic transverse crosssection of the device of Figure 1; Figure 3 is a diagrammatic side elevation of an alternative form of the device of Figure 1; and Figure 4 is a diagrammatic transverse cross-section of an alternative form of the roller members for the device of Figure 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT: The device of Figure 1 comprises two substantially parallel rollers 1 and 2 mounted on shafts journalled within a housing 3. If desired, the axes of rotation of the rollers can be splayed by, for example, 100 or the rollers can be correspondingly tapered so that the nip gap between them is broader at the tips of the rollers so as to aid guiding of the stems of feathers into the nip gap. For convenience, the invention will be described hereinafter in terms of parallel roller members 1. Preferably, housing 3 presents a rounded external surface to aid passage of the device through the feather covering of the carcass of the bird to be plucked. Suitable gearing is provided within the housing for coupling the rollers 1 and 2 to the drive chuck of a power drill 4 to which the housing 3 can be mounted in any suitable way.Alternatively, housing 3 can incorporate a suitable electric or other motor to drive the rollers directly; or the housing can have means for connecting the shafts carrying the rollers to a flexible cable drive to a remote motor drive (not shown). Both rollers may be driven, either in opposite directions and/or at different speeds in the same direction, so that the rollers gip and pull the stems of feathers away from the carcass to be plucked. However, it is within the scope of the present invention for one roller to be free running and to act as a plattern against which the opposed face of the other roller urges the stem of a feather to grip it and apply the desired pull.

As shown in Figures 1 and 2, roller 1 is a generally cylindrical roller having a number of axial flutes 5 formed in the surface thereof. The roller 1 and the flutes can be made from a metal or other rigid material and the flutes preferably have flattened crowns as shown in Figure 2 to reduce the risk that the flutes will cut through the stems of the feathers. Alternatively, the flutes 5 on roller 1 can be flexible, for example made from a suitable high friction surface rubber or plastic, so that they flex as they bear against the stem of a feather (as shown dotted) and pull the feather against the plattern effect of the opposed face of roller 2.

As shown in Figure 2, roller 2 can be a cylindrical roller with a generally smooth surface, for example provided by a hard and/or high friction rubber sleeve 6 which is a tight fit on the drive shaft 7 which extends for its full length.

In the alternative form of roller shown in Figure 4, both rollers have axial flutes which are out of register so that they interleave so that a stem is crimped between the opposing crown and flutes to aid gripping of the stem.

The rollers can be 5 to 10 cms long as shown in Figure 1 or can be 2 to 3 cm long as shown in Figure 3, in which latter case they are mounted with their axes of rotation at 300 to the longitudinal axis of housing 3.

Rollers 1 and 2 preferably have rounded or tapered free ends 8 and 9 as shown to assist guiding of the stem of a feather into the nip gap between the rollers.

Between the opposed surfaces of rollers 1 and 2 is an axial nip gap 10, which is typically a clearance gap between the roller surfaces. Where the rollers have interleaving flutes as shown in Figure 4, the nip gap is the gap between the interleaving surfaces of the rollers.

Where long rollers are used, it is desirable to blank off all but the last 2 to 5 cms of the nip gap to prevent pickup of excessive feathers in the upper portion of the nip gap as described above. The rollers 1 and 2 can be housed within an extension to housing 3, as shown in Figure 4, which surrounds the rollers circumferentially. However, it will usually be preferred to provide an axial shield plate 11 extending along that side of the rollers to be adjacent to the feather cover of the carcass. As shown in Figure 1, this shield plate is of a generally semi-circular form and extends axially to within 2 to 3 cms of the free ends of the rollers 1 and 2. Plate 11 is conveniently a metal plate extending axially from housing 3.

The housing 3 in the device of Figure 3 or the plate 11 of the device of Figure 1 carries a two pronged fork 20 which acts to guide the stem of feathers into the nip gap 10 where they are gripped by the rollers 1 and 2 and pulled out of the carcass. The tines of the fork are preferably splayed laterally and are curved as shown in Figure 3. It is also preferred that the gap between the tines at the nip gap end of the fork corresponds to the diameter of an average feather stem to enter the nip gap between the rollers so that stems will be fed sequentially and singly to the nip gap rather than in large numbers simultaneously.

In operation, the rollers 1 and 2 are rotated at from 2000 to 3000 rpm and the free end of the device is inserted axially into the feather cover of the carcass so that the tines of the fork 20 lie adjacent to and move generally parallel to the skin of the carcass. When a stem enters the fork, it is guided into the nip gap between the rollers 1 and 2 where it is gripped by the rollers and pulled out of the carcass.

The invention has been described above in terms of a device having one pair of roller members. However, it will be appreciated that for larger carcasses it may be possible to use machines which carry two or more pairs of rollers, for example as two plucking heads operated in parallel from a single power source.

Claims

CLAIMS:

1. A hand portable plucking device for removing feathers from the carcass of a bird, which device comprises: a. a pair of generally cylindrical rotatable roller members having their longitudinal axes substantially parallel to one another and spaced apart so as to provide a nip gap between the opposed surfaces of the roller members, the nip gap being adapted to receive a feather and to grip the stem of the feather between the opposed surfaces of the roller members so as to apply axial tension to the feather as the roller members rotate; b. means located at or adjacent one end of the said roller members for rotating at least one of the roller members about its longitudinal axis; and c. guide means located at the other end of said roller members for guiding the stem of a feather into the nip gap between the roller members.

2. A device as claimed in claim 1 wherein one or both roller members have a high friction surface having radial projections.

3. A device as claimed in either of claims 1 or 2 wherein the effective length of the nip gap is from 2 to 5 cms.

4. A device as claimed in claim 3 wherein there is provided a shielding member which restricts access to the nip gap, said shielding member extending from said one end to a point intermediate the ends of said roller members.

5. A device as claimed in claim 4 wherein said shielding member comprises a semi-circular member shielding that side of the roller members to be adjacent the feather cover of the carcass of the bird to be plucked.

6. A device as claimed in any one of the preceding claims wherein the guide member comprises a forked member extending beyond the said other ends of the roller members.

7. A device as claimed in any one of the preceding claims wherein the device is adapted to be mounted upon a hand held power tool to provide the motive power for the roller members.

8. A device as claimed in any one of claims 1 to 6 wherein the device is adapted to be connected to a flexible drive shaft driven by a remote motive power source.

9. A device substantially as hereinbefore described with respect to and as shown in any one of the accompanying drawings.

10. A method for removing feathers from the carcass of a bird, which method comprises passing a device as claimed in any one of the preceding claims over the carcess with its operative end within the feather covering of the carcass so that the stems of feathers are guided into the nip gap between the rotating roller members of the device whereby the stems of the feathers are gripped by the surface of one or both rotating roller members so as to apply axial tension to the stem and withdraw it from the carcass.