The invention relates to a system and method for removing undesirable material from a surface of a carcass or parts hereof such as from meat product. Undesirable material may be bone fragments, meat/fat/tendon fragments and/or foreign bodies. The system is based on vacuum to aspirate undesirable material and is preferably used without steam or water.

Background of invention

To increase food safety and food quality there is an increasing focus on minimizing and/or removing undesirable material from carcasses or parts thereof under treatment in the food processing industry. Some cleaning of carcasses or parts thereof (hereinafter denoted 'meat product') may be performed by a combination of applying steam or water to the meat product and aspirating the steam or water together with impurities and other undesirable materials, hereby cleaning the meat product. However, some meat products should not be exposed to steam or water for a number of reasons such as 1) the meat should be kept dry to have a high quality, 2) water is undesirable as this may result in problems such as difficulties in the packaging process, 3) handling water increases the costs, 4) water may increase growth of microorganisms.

A suction device for automatic dry suction of meat is known from DK 177163. This suction device has a number of drag heads located with distance between each other. The drag heads can be located in one row or in more than one row to make it possible to aspirate e.g. bone fragments from a pork breast/belly piece just by passing the suction device past the breast/belly piece one time when the

breast/belly piece are transported by a conveyor belt past the suction device i.e. the group of drag heads should create a width corresponding to the width of the transported meat pieces, where the 'width' correspond to the meat product's dimension perpendicular to the transport direction. Each drag head is movable suspended such that the drag head can move up and down according to the surface variation of the breast/belly piece. However, it has been observed that the quality of treated meat pieces are not sufficient as too many bone fragments, other loose fragments origination from the carcass and also too many foreign bodies are left on the meat pieces after treatment. Although the drag heads show some mechanical flexibility, it has turned out that this flexibility is not sufficient to obtain the required meat product quality and the system is not suitable for an automatic vacuum cleaning system comprising an industrial robot. Summary of invention

The invention relates to a vacuum cleaner for aspirating undesirable material from a surface of a meat product, where such undesirable material may be any fragments existing from the processing of a carcass or parts hereof or the fragments may be foreign bodies located on the meat product.

The vacuum cleaner for aspirating undesirable material from a surface of a meat product comprises a drag head, which may comprise a. A drag head body,

b. An aspiration opening in the drag head body,

c. At least one spacer with a resting area, the spacer being connected to the drag head body in front of and/or alongside the aspiration opening and with the resting area located away from the aspiration opening such that the resting area can rest on a meat product surface during application, d. At least one slide shoe with a sliding part comprising a first sliding area, the slide shoe being arranged besides the drag head body such that at least part of the first sliding area is substantially parallel to at least a part of the resting area of the spacer, and

wherein the slide shoe is movable in a direction substantially perpendicular to the resting area of the spacer. The slide shoe may comprise at least one feature selected from the group of:

• A fixing arm connected to a sliding part with the sliding areas,

• The slide shoe may be located beside at least one of the drag heads without being fastened directly to the drag head such that the slide shoe is capable of performing a resilient movement perpendicular to the transport direction during application,

• The slide shoe may have a total length being at least twice the length of the resting area of the spacer,

• The slide shoe may have a first sliding area being parallel to the resting area of the spacer and a second sliding area in a first end of the first sliding area and a third sliding area in a second end of the first sliding area,

• The second sliding area and the third sliding area may be slightly

bending towards the fixing arm,

• The total length of the sliding part may be at least 6 cm, such as

between 9 and 11 cm. An aspiration means for a vacuum cleaner for aspirating undesirable material from a meat product may comprise a. at least one drag head, such as at least two drag heads,

b. at least one drag head coupling for connecting the at least one drag head to at least one suction tube,

c. at least one fixing bar for joining a number of suction tubes each connected to a drag head and/or for joining a number of drag heads,

d. at least one management coupling for connecting the at least one drag head each with a suction tube to a management system, such as an automatic management system, such as an industrial robot.

In the aspiration means:

• The slide shoe may comprising a fixing arm being fixed to the fixing bar, to the suction tube or to the drag head by a pivot making the slide shoe capable of performing a resilient movement,

· The fixing bar may be fixed in a non-moving position holding the at least one, such as at least two drag heads or suction tubes next to each other and with a predetermined distance between the at least two drag heads or suction tubes,

• The fixing bar may be located above the at least one, such as at least two drag heads or suction tubes, where above is determined in respect of the location during application on a horizontally located meat piece,

• The at least one, such as at least two drag heads or suction tubes may be connected to the fixing bar by a resilient connection such that each of the at least one, such as at least two drag heads or suction tubes are capable of resilient movement perpendicular to the movement direction during application.

An automatic vacuum cleaning system for aspirating undesirable material from a meat product may comprise at least one aspiration means and a management system such as an industrial robot, at least one trigger system for determining and signaling presence of a meat product to be treated, and a processor comprising an algorithm determining the movement pattern of the at least one drag head during treatment of the meat product.

In a method for removing loose material from the surface of a carcass or meat piece, the method may comprise the step of a. Providing an aspiration means or an automatic vacuum cleaning system, b. Positioning a carcass or meat piece at a handling area in proximity to the aspiration means or of the automatic vacuum cleaning system,

c. Removing loose material from the surface of the carcass or meat piece by guiding the at least one drag head one or more times along the surface of the carcass or meat piece with a vacuum suction in the drag head and hereby removing loose material from the surface of the carcass or meat piece.

Brief description of figures

Fig. 1 illustrates a drag head observed from a first angle.

Fig. 2 illustrates a drag head observed from a second angle.

Fig. 3 illustrates a drag head observed from a third angle.

Fig. 4 illustrates a slide shoe.

Fig. 5 illustrates an aspiration means with 5 drag heads.

Fig. 6 illustrates an aspiration means with 6 drag heads.

Fig. 7 illustrates an automatic vacuum cleaning system.

Detailed description of the invention

An aspect of the invention relates to a drag head system for a vacuum cleaner such as an automatic vacuum cleaner for aspirating undesirable material from a surface such as from a surface of a meat product, the drag head system may comprise a. A drag head body with an aspiration opening or inlet opening for letting in air and loose or unattached material such as loose undesirable material on a meat piece surface,

b. At least one spacer with a resting area, the spacer being connected to the drag head body in front of and/or alongside the aspiration opening and with the resting area located away from the aspiration opening such that the resting area can rest on a meat product surface during application, c. Optionally, at least one slide shoe with a sliding part comprising a first

sliding area, the slide shoe being arranged besides the drag head body such that at least part of the first sliding area is substantially parallel to at least a part of the resting area of the at least one spacer,

wherein the slide shoe is independently movable in a direction substantially perpendicular to the resting area of the spacer. The purpose of the spacer is to create a space or distance between the aspiration opening of the drag head body and a meat product surface during application when air is aspirated through the drag head body. The spacer will secure the drag head body will not adhere to the surface of a meat product and this secures sufficient air transport into the drag head body making it capable of aspirating into the drag head body loose and unattached material located on the meat product surface.

The purpose of the slide shoe is to secure any part of the meat piece do not flip around part of the drag head body as this may decrease and/or interrupt the air flow during the aspiration process such that some items of loose or unattached material on the meat product surface are not removed from the surface. The slide shoe may be independently movable in a direction substantially perpendicular to the resting area of the spacer, this also means movable substantially towards the aspiration opening, or substantially perpendicular to the direction of transport during application, or movable in a direction away from the meat piece surface which is under treatment. This independently movement makes the slide shoe capable of following the contour of the surface of the meat piece.

The drag head body may comprise at least one feature selected from the group of:

• A drag head housing with an outline which is a truncated cylinder,

· The truncation of the drag head housing constitute the aspiration opening,

• The even planes of the truncated cylinder comprises side parts of the drag head body,

• An outlet opening substantially opposite of the aspiration opening or in-let opening. The drag head body may have any other suitable outline, such as V-shaped and which is oblong in a direction perpendicular to the overall air-flow direction through the drag head body i.e. the drag head body is preferably not cone-shaped. The large part of the V-shaped drag head body may include an aspiration opening and the smallest part of the V-shaped drag head body may comprise an outlet opening, or vice-versa. Preferably the drag head body has even planes as side parts of the drag head body, these even side parts make it possible to use more drag head bodies to design an aspiration means as described elsewhere herein.

The aspiration opening of the drag head body may comprise at least one feature selected from the group of: • It is a four-sided opening when observed perpendicularly to a rectangle produced from the sides of the opening,

• Each side along the aspiration opening is in similar level,

• It is preferably squared or rectangular when observed in the direction of the air flow during aspiration.

• It has a length of between 5 and 50 mm, such as between 10 and 40 mm, e.g. between 15 and 30 mm, such as between 20 and 25 mm, e.g. about 22 mm, and wherein the length is parallel to the transport direction during application of the drag head,

· It has a width of between 100 and 10 mm, such as between 90 and 15 mm, e.g. between 80 and 20 mm, such as between 70 and 25 mm, e.g. between 60 and 25 mm, such as between 50 and 30 mm, e.g. between 45 and 35 mm, such as about 40 mm, and wherein the width is perpendicular to the transport direction during application of the drag head, and substantially parallel to a meat product surface being treated,

• The aspiration opening is divided into a number of sub-openings by the at least one spacer and wherein the sub-openings each has a length

corresponding to the length of the aspiration opening,

• The sub-openings each has a width which is less than half the width of the aspiration opening and the width of the sub-openings is between 4 and 20 mm, such as between 5 and 17 mm, e.g . between 6 and 15 mm, such as between 7 and 13 mm, e.g. between 8 and 11 mm, such as between 8 and 10 mm, e.g. about 9 mm.

• The distance between each two spacers is preferably such that the meat product surface is not drawn towards the aspiration opening to an extent adversely reducing the aspiration effect during application of the drag head.

The spacer of the drag head may comprise at least one feature selected from the group of:

• The resting area is preferably plane or the end parts of the resting area bend slightly towards the aspiration opening of the drag head body when the spacer is mounted on the drag head body,

• The resting area preferably has a length corresponding at least to the

aspiration opening length,

• The spacer is at least 2 mm in height, such as at least 4 mm, e.g. at least 6 mm, such as at least 8 mm, e.g. at least 10 mm, creating substantially a corresponding height of space between the aspiration opening and a meat product surface during application,

• The spacer has at least one rounded part located along and outside of a rounded part of the drag head body, the at least one rounded part of the spacer bending away from a meat product surface during application.

• The rounded part of the spacer may at one end of the spacer encircle the drag head body substantially ½ to Vi the way from the aspiration opening to a top point of the drag head body. The rounded part of the spacer may at the other end of the spacer encircle the drag head body substantially ½ to ¾, preferably Vi to ¾, the way from the aspiration opening to a top point of the drag head body. However, the spacer may also fully encircle the drag head body or may follow the drag head body to a location where an outlet of the drag head is located .

The slide shoe may comprise at least one feature selected from the group of: · The slide shoe comprises a fixing arm connected to a sliding part with the sliding areas, and where the fixing arm is used to attach the slide shoe to an aspiration means,

• The slide shoe may be located beside at least one drag head without being fastened directly to the drag head and such that the slide shoe is capable of performing a resilient movement perpendicular to the transport direction during application, this movement direction is also parallel to a side of the drag head body,

• Each slide shoe may move independently of the drag head(s) of an

aspiration means,

· The sliding part of the slide shoe has a total length being at least twice the length of the resting area of the spacer, such as substantially three times the length of the resting area,

• The sliding part of the slide shoe has a first sliding area being substantially parallel to the resting area of the spacer and a second sliding area in a first end of the first sliding area and a third sliding area in a second end of the first sliding area,

• The second sliding area and the third sliding area are slightly bending

towards the fixing arm such that the total sliding area of the first, second and third sliding area is an smooth curve, which bends upward in respect to the first sliding area when observing the slide shoe in a side view and upward in respect to when the slide shoe rests on the upper side of a meat piece being located horizontally,

• The total length of the sliding part may be at least 6 cm, such as at least 7 cm, e.g. at least 8 cm, such as at least 9 cm, e.g. at least 10 cm, such as between 9 and 11 cm, e.g. substantially about 10 cm,

• The slide shoe may be arranged beside a spacer such that substantially the same length of the sliding part protrudes in each direction of the spacer i.e. in a first end and in a second end of the spacer according to the transport direction during application,

· The second sliding are and the third sliding area of the slide shoe may each extend at least 1 cm from the resting area of the spacer, such as at least 2 cm, e.g. at least 3 cm, such as at least 4 cm, e.g. at least 3 cm, and where the second sliding area and the third sliding area need not extend a similar length from the resting area of the spacer. The number of slide shoes is preferably equal to the number of drag heads added by one, such that each drag heads has slide shoes located at both sides.

Another aspect of the invention relates to an aspiration means for a vacuum cleaner for aspirating undesirable material from a meat product, the aspiration means may comprise a. at least one drag head as described herein, such as at least two drag heads, b. at least one drag head coupling for connecting each of the at least one drag head to at least one suction tube,

c. at least one fixing bar for joining a number of drag heads or suction tubes each connected to a drag head,

d. at least one management coupling for connecting the at least one drag head each with a suction tube to a management system, such as an automatic management system such as an industrial robot.

The vacuum cleaner may be an automatic vacuum cleaner, such as a robot controlled vacuum cleaner. The robot may be an industrial robot capable of controlling the location of the aspiration means in three dimensions.

The aspiration means may have a design, wherein :

• The at least one slide shoe comprises a fixing arm being fixed to the fixing bar, to the suction tube or to the drag head by a pivot making the slide shoe capable of performing a resilient movement, such as a resilient movement being independently of the movement of the drag head during application, • The fixing bar may be fixed in a non-moving position holding the at least one drag head or suction tube, such as the at least two drag heads or suction tubes next to each other and with a predetermined distance between the at least two drag heads or suction tubes,

· The fixing bar may be located above the at least one, such as at least two drag heads or suction tubes, where above is in respect to the orientation of the aspiration means during application on the upper side of a horizontally located meat piece,

• The at least one, such as at least two drag heads or suction tubes being connected to the fixing bar by a resilient connection such that each of the at least one, such as at least two suction tubes are capable of resilient movement perpendicular to the movement direction during application,

• The at least one coupling for connecting the at least one drag head to a management system being located at the fixing bar, The drag heads of the aspiration means may be independently movable such that the drag heads may follow the contour of a meat piece during application.

A further aspect of the invention relates to an automatic vacuum cleaning system for aspirating undesirable material from a meat product, the automatic vacuum cleaning system may comprise at least one aspiration means as described herein and a management system such as an industrial robot, at least one trigger system for determining and signaling presence of a meat product to be treated, and a processor comprising an algorithm determining the movement pattern of the at least one drag head during treatment of the meat product.

The trigger system may be a system which in a simple way determines presence or absence of a meat piece product in a treatment zone or handling area. When a meat piece product is present in such a treatment zone or handling area the automatic vacuum cleaning system may aspirate undesirable material from the surface of the meat product. The movement of the vacuum cleaning system may be in a predetermined path. The trigger signal may cause the automatic system to direct the aspiration means to a predetermined location in space corresponding to an end of a meat piece to be treated and from which location the aspiration means is handled in a predetermined path securing the aspiration means is passed over the meat product surface in one or more movements to aspirate loose material from the surface of the meat product. The trigger system may also be a system comprising a vision system which is capable of determine the presence of a meat piece in a treatment zone or handling area and e.g. also the positioning and/or the orientation and/or the length and/or the width and/or the height of the meat piece. Information from a vision system may be used to determine the movement path of the vacuum cleaning system e.g. including determination of whether the meat piece is non-moving or moving e.g. by a conveyor belt.

Another aspect of the invention relates to a method for removing loose material from the surface of a carcass or from the surface of a meat piece, the method may comprise the step of a. Providing an aspiration means as described herein or an automatic vacuum cleaning system as described herein,

b. Positioning a carcass or meat piece in a treatment zone or handling area in proximity to the aspiration means or of the automatic vacuum cleaning system,

c. Removing loose material from the surface of the carcass or meat piece by guiding the at least one drag head one or more times along the surface of the carcass or meat piece with a vacuum suction in the drag head and hereby removing loose material from the surface of the carcass or meat piece.

A meat piece surface may be treated a predetermined number of times by the at least one drag head or aspiration means and the number of times may be dependent on the required quality of the meat piece i.e. the allowed number or amount of undesirable material, such as number or amount of bone fragments. Preferably the at least one drag head is only guided one time pass a section of the surface of a carcass or of a meat piece, however, the at least one drag head or aspiration means may have a dimension which is not sufficient to bridge the meat piece and thus not capable in just one go to treat the entire meat piece surface which should be treated, in such a situation the at least one drag head may be guided along the surface to be treated a number of times and such that at least an untreated area of the meat piece surface is treated in each round. Partly overlap between treated areas may occur when treating a meat piece surface by passing the at least one drag head or aspiration means along a meat product in two or more rounds.

A further aspect of the invention relates to use of at least one drag head as described herein, of an aspiration means as described herein or of an automatic vacuum cleaner as described herein, such as for use in the method as described herein. Preferably the at least one drag head, aspiration means or automatic vacuum cleaner is used for removal of undesirable material from the surface of a carcass or from the surface of a meat piece. Undesirable material may be any loose material being present on the surface of a carcass or on the surface of a meat piece.

Preferably the meat piece is a meat piece which has been treated by a cutting means such as a knife or a saw and where there is a risk of fragments of bones or cartilage on the surface of the meat piece. Preferred meat pieces to treat are belly pieces or breast prices from pig, cattle/cow, sheep, goats, deer etc

A meat piece should be understood as any part of an animal carcass. Detailed description of the figures

Fig. 1 illustrates a of a drag head (1) from a first angle. The drag head ( 1) comprises a drag head body (2) with a drag head housing (11) with an aspiration opening (3) to aspirate loose material. To make a distance from the aspiration opening (3) a number of spacers (4) are located at the flank of the aspiration opening (3) and/or passing the opening of the aspiration opening (3). Each spacer (4) has a resting area (5) suitable to rest on the surface of a meat product and the height of the first spacing section (6), the second spacing section (7) and the third spacing section (8) of the spacer (4) creates space for airflow during vacuuming, secure an optimal turbulence of the air at the surface of the meat product and participate in securing the meat product does not stick to the drag head (1) during application.

Fig. 2 illustrates a drag head (1) observed from a second angle. Further description is present in the description of Fig. 1.

Fig. 3 illustrates the drag head (1) observed from a third angle. To the drag head body (2) are attached three spacers (4) in the zone with the aspiration opening (3). The space for air flow as described in respect of Fig. 1 is illustrated in front of the aspiration opening (3).

Fig. 4 illustrates a slide shoe (9) observed perpendicular to the movement direction during application. The slide shoe (9) has a first sliding area (10), a second sliding area (13) and a third sliding area (14) each sliding area being facing the surface of a meat product during application. A fixing arm (28) makes it capable to mount the slide shoe (9) such that the sliding areas (10, 13, 14) and the fixing arm (28) can perform resilient movement during application. Fastening apertures (23) are shown where one (the large) aperture can be used for pivotally fastening the slide shoe (9) and the other apertures (the small ones) can be used for means forcing the slide shoe (9) to a starting position when no force is applied upon the first sliding area (10), second sliding area (13) and/or third sliding area (14). The second sliding area (13) and third sliding area (14) are bending slightly upward (towards the fixing arm (21)) from the first sliding area (10). The sliding area along the second sliding area (13), the first sliding area (10) and the third sliding area (14) is curved without any sharp edges in the curvature and hereby securing the slide shoe (9) slides across the meat product surface during application and does not stick to the meat product surface.

Fig. 5 illustrates an aspiration means (15) with 5 drag heads (1). The aspiration means (15) may comprise any number of drag heads (1) with spacers (4) and slide shoes (9) between the drag heads (1). Each drag head (1) is connected to a suction tube (17) which may be of a hygienic material such as metal in the part (17-A) nearest the drag head (1) and may be of a flexible material a part (17-B) further away from the drag head (1). The two parts of the suction tube (17) may be connected at a suction tube joint (18). The suction tubes (17) are connected to a fixing bar (21) in a movable manner where resilient connections (25-A) in one part of the fixing bar (21) secure the suction tubes ( 17) are pushed to a start position when no or little pressure is applied to a drag head (1). In this illustration a slide shoe (9) is exposed and illustrated is a pivot (22) for connecting the slide shoe (9) to the fixing bar (21) and resilient connections (25-B) in the back of the fixing bar (21) for pulling the slide shoe (9) to a start position when no or little pressure is applied to the slide shoe (9). Illustrated is also an aperture (24) for a stopper, where the stopper can be a pin or small shaft (not illustrated) which will aim at the fixing bar (21) securing the slide shoe (9) cannot move downward in respect of a start position. The suction tubes (17) are only illustrated for a part of the system, however, the outlet (26) should be connected to a vacuum pump (not illustrated). Each suction tube (17) may be connected to a vacuum pump or the illustrated suction tubes (17) may be connected into fewer suction tubes at an appropriate distance from the drag heads (1) securing the correct vacuum in each drag head (1).

Fig. 6 illustrates an aspiration means (15) with 6 drag heads (1). For explanation see text in respect of Fig. 5. This is a preferred aspiration means (15) with each slide shoes (9) located between two drag heads (1) and with a total width of about 30-35 cm which is suitable for treating most pork belly pieces by passing the aspiration means (15) a single time along the belly piece obtained from pigs with a slaughter weight of about 80-120 kg. Fig. 7 illustrates an automatic vacuum cleaning system (27). The aspiration means (15) of Fig. 6 is connected to an industrial robot (20) at the management coupling. The robot (20) is illustrated located above the aspiration means (15) giving space for conveyor belt(s) (not illustrated) transporting meat pieces to be treated and if required operators performing other operations close to the automatic vacuum cleaning system (27). The suction tubes (17) are illustrated in a longer form than in Fig. 6 and each with a flexible tube towards the outlets (26), which should be connected to a vacuum producing system.

List of reference signs In the figures, identical structures, elements or parts that appear in more than one figure are generally labeled with the same numeral in all the figures in which they appear.

1. Drag head

2. Drag head body

3. Aspiration opening

4. Spacer

5. Resting area of spacer

6. First spacing section

7. Second spacing section

8. Third spacing section

9. Slide shoe

10. First sliding area

11. Drag head housing

12. Outlet

13. Second sliding area

14. Third sliding area

15. Aspiration means

16. Drag head coupling

17. Suction tube

18. Suction tube joint

19. Management coupli

20. Industrial robot

21. Fixing bar

22. Pivot

23. Fastening apertures

24. Aperture for stopper 25. Resilient connection

26. Outlet of suction tube

27. Automatic vacuum cleaning system

28. Fixing arm