EXTRUDER SCREW HANDLING DEVICE

Abstract

An extruder screw-handling device for handling a screw of a food or land-or-sea-animal-feed extruder, the device being suitable for fully extracting an extruder screw from an extruder barrel, wherein the device has a horizontally arranged top section, a locking screw assembly and a guiding element. The present invention is furthermore related to a method of extracting an extruder screw from a food or land-or-sea-animal-feed extruder using the device.

Claims

1-15. (canceled)

16: An extruder screw handling device for extracting and/or inserting at least one extruder screw of a food or land-or-sea-animal-feed extruder, said device being suitable for fully extracting the extruder screw from a barrel of the extruder and/or for fully inserting the extruder screw into a barrel of the extruder, in which barrel the extruder screw rotates when the extruder is operating to extrude food or animal-feed product, wherein said device comprises: a locking screw assembly that is configured so as to be securely and releasably attachable to an end section of the extruder screw; and, actuating means for moving the locking screw assembly away from the extruder, whereby, when the device is in operation to extract the extruder screw, moving the extruder screw, when securely attached to the locking screw assembly, out of its extruder barrel; wherein the device further comprises: a horizontally-arranged top section, which is at least half as long as the extruder screw that is to be extracted; a plurality of wheels; a support structure which supports the top section and which is supported on the ground by the plurality of wheels; a guiding element which is mounted on and towards one end of said top section, said guiding element having an opening through which the extruder screw can be moved during extraction; and a guide means which are mounted on the top section and which guide motion of the locking screw assembly, which is movably connected to said guide means, wherein the locking screw assembly comprises a central opening for secure and releasable attachment of the extruder screw, wherein the actuating means are mounted on an outer surface of the locking screw assembly, whereby the extruder screw handling device is further suitable: for transporting the extruder screw after extraction from the extruder; and for enabling access to the extruder screw to carry out maintenance and/or cleaning tasks.

17: The device according to claim 16, wherein the top section is as long as or longer than the extruder screw that is to be extracted.

18: The device according to claim 16, wherein said top section comprises at least one, and preferably at least two, array(s) of openings over at least 75% of the length of the top section.

19: The device according to claim 18, wherein the stopper element(s) is/are provided which can be inserted into the array of openings.

20: The device according to claim 16, wherein the device further comprises a device attachment means for securely and releasably attaching the device to the extruder and/or the guiding element comprises guiding element attachment means for releasably attaching the guiding element to the extruder.

21: The device according to claim 16, wherein said guide means comprise guide rails.

22: The device according to claim 16, wherein said actuating means comprise at least one hydraulic cylinder, preferably two hydraulic cylinders, and especially preferred double-acting hydraulic cylinder(s).

23: The device according to claim 16, wherein the device further comprises a wheel driving means for driving at least one of the wheels and a drive wheel control means.

24: The device according to claim 16, wherein said device further comprises motive power components selected from the group consisting of electric power supply components, hydraulic medium supply components, and combinations thereof.

25: The device according to claim 16, wherein the support structure comprises height adjusting means for adjusting the height of the device.

26: The device according to claim 23, wherein said motive power components are connected to at least two of the actuating means, the locking screw assembly, the wheel driving means, the device attachment means, and the height adjusting means in such a way that motive power is supplied thereto.

27: A method for extracting an extruder screw from a food or land-or-sea-animal-feed extruder, comprising the steps: a) providing an extruder screw handling device according to claim 16 in close proximity to the extruder so that the extruder screw of the extruder extends through a guiding element of the device, b) securely and releasably attaching an end section of the extruder screw to a locking screw assembly of the device, c) actuating at least one actuating means mounted on the locking screw assembly, wherein said actuating means push the locking screw assembly away from either said guiding element, or from stopper element(s) positioned in a first one or pair of at least one, preferably two, array(s) of openings, thereby moving the locking screw assembly, and the end section of the extruder screw attached thereto, away from the extruder, d) inserting the stopper element(s) in a second one or pair of the opening(s) of the array(s) of openings, wherein the second opening(s) are further away from the extruder than the first opening(s), e) optionally repeating steps c) and d).

28: The method according to claim 27, wherein steps c) and d) are repeated until the extruder screw is fully extracted from the extruder.

29: The method according to claim 28, wherein prior to step b) the device is releasably and securely attached to the extruder and after the extruder screw is fully extracted from the extruder, the device is disconnected from the extruder, so that the extruder screw can be transported on the device.

30: A method for carrying out maintenance and/or cleaning tasks on an extruder screw of a food or land-or-sea-animal-feed extruder, the method comprising the steps of extracting the extruder screw from the extruder by the method according claim 27, and performing the chosen task on the extracted extruder screw while mounted on the device.

Description

[0073] The present invention will now be explained in more detail with reference to non-limiting embodiments and drawings.

[0074] FIG. 1 shows one embodiment of the screw-handling device of the present invention

[0075] FIGS. 2-6 shows different stages of an embodiment of the present invention of extracting an extruder screw out of a single-screw extruder

[0076] In FIG. 1 there is shown one embodiment of the screw-handling device 1 of the present invention. The device 1 comprises, as a support structure, frame parts 2, 4, 5 which in this embodiment are made of metal tubes that are connected with each other. At one end of frame part 5 there are provided pins 5a for attaching the device 1 to an extruder, preferably a single-screw extruder (not shown here). A pair of front wheels 3a and a pair of back wheels 3b are provided on the frame part 2 by means of a screw connection that allows adjustment of the height of the device 1.

[0077] A drive wheel control means 6 is operatively connected via a wheel drive means to the pair of front wheels 3a, thus allowing easy movement of the device 1. At the end of the drive wheel control means 6, a handle 7a and a control panel 7b are provided. With the aid of the control panel 7b, movement of the device 1 can be controlled, i.e. in this embodiment the pair of front wheels is driven with electric power when the respective button on the control panel 7b is pushed.

[0078] On the frame part 5, a top section 8 of the device 1 is provided. Said top section 8 comprises two arrays of openings 9 and two guide rails 10.

[0079] At one end of the top section 8, a guiding element 11 is fixedly provided. Said guiding element 11 comprises an opening 11a formed from an upper section and a lower section of the guiding element 11. The upper section can be removed for insertion of an extruder screw of an extruder, preferably single-screw extruder, into the opening 11a of the guiding element 11. Furthermore, bores 11b are provided in the guiding element 11 for attaching the guiding element 11 to an extruder, preferably single-screw extruder (not shown here), by means of bolts (not shown here) which are led through the bores 11b and releasably fixed at the extruder.

[0080] On the top section 8, furthermore a locking screw assembly 12 is movably provided. Said locking screw assembly 12 may glide on the guide rails 10. Said locking screw assembly 12 comprises an opening 12a in which an extruder screw of an extruder, preferably single-screw extruder, can be securely and releasably attached (by means of a locking ring not shown here). On each side of the locking screw assembly 12 there is provided a hydraulic cylinder 12b.

[0081] The device 1 furthermore comprises a battery 13a for electric power supply (e.g. for the drive wheel control means 6), a hydraulic aggregate 13b for the supply of hydraulic medium to the hydraulic cylinder 12b via hoses (not shown here), and a control unit 13c for the operation of the hydraulic cylinders 12b.

[0082] FIGS. 2 to 6 show an embodiment of the method according to the present invention of extracting an extruder screw from an extruder, preferably single-screw extruder.

[0083] In FIG. 2, the screw-handling device 1 according to the present invention is moved to a single-screw extruder 14 with an extruder screw 15. The device 1 is attached to the extruder 14 with the aid of pins 5a as well as bolts (not shown here) that are inserted into bores (not shown here) of the guiding element 11.

[0084] In FIG. 3, the screw-handling device 1 according to the present invention is attached to the extruder 14. The extruder screw 15 of the extruder 15 has been led through the opening 11a of the guiding element 11.

[0085] In FIG. 4, the screw locking assembly 12 has been moved onto the extruder screw 15, so that the extruder screw 15 is within the opening 12a of the screw locking assembly 12. By rotating the locking ring 12c, the extruder screw 15 is fastened within the opening 12a of the screw locking assembly 12. The device is ready for a first stroke of the hydraulic cylinders for pulling the extruder screw 15 out of the extruder 14. The first stroke is carried out by actuating the hydraulic cylinders 12b, which push themselves away from counter-elements 11c that are provided on the sides of the guiding element 11. In this embodiment, the counter-elements 11c have the form of metal sheets.

[0086] In FIG. 5, the first stroke of the hydraulic cylinders 12b has been carried out. The screw locking assembly 12 and the extruder screw 15 fastened therein has moved away from the extruder 14 by a distance of about 150-300 mm. The screw locking assembly 12 moves by means of gliding shoes 12d on guide rails 10. For carrying out the next stroke, stopper elements 16 are now provided in openings of the arrays 9 that are adjacent to the screw locking assembly 12. Typically, the openings most adjacent to the screw locking assembly 12 that can be accessed by the stopper elements 16 are used in this step. The hydraulic cylinders 12b are actuated, and push themselves away from the stopper elements 16, so that the screw locking assembly 12 and the extruder screw 15 fastened therein moves away from the extruder 14 at each stroke by a distance of about 150-300 mm.

[0087] In FIG. 6, it can be seen that after repeated strokes of the hydraulic cylinders 12b, the screw locking assembly 12 has arrived at the end of the screw-handling device 1, thereby fully extracting the extruder screw 15 fastened in the screw locking assembly 12 from the extruder 14. The screw-handling device 1 can now be removed from the extruder 14 and moved around using the drive wheel control means 6 with its attached handle 7a and control panel 7b.