DK2325584T3

DK2325584T3 - Freezer

Info

Publication number: DK2325584T3
Application number: DK10191534.6T
Authority: DK
Inventors: Thomas Völkl
Original assignee: Tvi Entw & Produktion Gmbh
Priority date: 2009-11-17
Filing date: 2010-11-17
Publication date: 2018-01-22
Also published as: EP2325584A3; DE102009053321B4; EP2325584B1; DE102009053321A1; EP2325584A2; PL2325584T3; ES2652172T3

Description

The invention relates to freezers for quick surface freezing of freezing material. II. Technical Background

Freezers that are configured to quickly provide freezing material with a deep frozen outer layer in order to facilitate subsequent processing are advantageously produced as pass through freezers so that they can be integrated into a continuously operating freezer line. The freezers are typically configured as band frosters or spiral frosters where the product to be frozen is applied at one end at a loading opening onto the band of the froster, runs through the froster on the band typically horizontally and straight and leaves the froster in a frozen state at a retrieval opening that is arranged at an opposite end.

Freezers of this type in particular configured as band frosters require a large set up surface in particular in a longitudinal direction and in particular when loading and unloading in a non-fully automatic manner they require two operators namely at the loading opening and at the retrieval opening.

Additionally freezers are known which like a typical freezer have a single door and which are loaded up once with products to be frozen and wherein the door is subsequently closed until the products received in the freezer are sufficiently frozen at their surface. Subsequently the entire content of frozen material is retrieved and the freezer is filled with products to be frozen.

The freezers have a much smaller set up surface, require only a single operator but they do not facilitate continuous feeding and retrieval.

Additionally freezers are known where the material to be frozen is typically inserted into a basket piece by piece and the baskets rotate in the freezer in a revolving row or serpentine. The baskets are thus either hooked up on both sides in endless circumferential chains or carrier belts which take over transportation like e.g. in US 4,138,360 or they are pushed without physical connection merely due to form locking in a meandering patter through an interior of the freezer like in the most pertinent reference DE 20 2008 014 478 U1 which discloses a freezer according to the preamble of claim 1. III. Brief Summary of the Invention a) Technical object

Thus, it is an object of the invention to provide a freezer with a small set up surface and low operating complexity wherein the freezer still provides continuous freezing operations. b) Solution

The object tis achieved by the features of claim 1, advantageous embodiments can be derived from the dependent claims.

Through the arrangement of loading opening and retrieval opening on an identical side in the housing of the freezer a single operator suffices for loading and unloading.

In order to perform continuous loading and unloading and thus also continuous freezing the baskets with the freezing material circulate in an interior of the housing and thus move along their circulation path typically in a vertical direction directly behind the loading opening and the retrieval opening of the freezer.

For example when the retrieval opening is arranged above the loading opening the baskets have to move behind these openings top down since a piece of freezing material to be frozen is to be inserted into the basket from which a frozen piece of freezing material was retrieved at the upper retrieval opening, wherein the piece of freezing material to be frozen is inserted immediately thereafter and below at the loading opening.

The baskets can stop for a short period of time at the positions of the openings or they can move continuously by the openings slowly.

This way loading and retrieval can be performed through the same opening by initially emptying a basket behind this opening and by immediately refilling the basket.

Advantageously, however, at least retrieving the frozen freezing material is performed automatically and therefore separate openings are required.

The baskets are made from prongs that are arranged adjacent from one another with an offset and transversal to a movement direction of the baskets, wherein the freezing material sits on the prongs and so that a basket is created which is open in upward direction and essentially also in forward direction towards the operator.

The prongs are only connected with each other at a back side that is oriented away from the operator.

Thus, retrieval can be performed automatically using a retrieval rake which permanently protrudes from an inside of the housing into an interior in the portion of the retrieval opening or directly below and whose prongs are sized and offset so that the prongs of the basket during a movement of the basket move downward between the prongs of the retrieval rake and thus the freezing material automatically remains on the retrieval rake.

Since the retrieval rake is either sloped at a slant angle downward to the outside or includes a corresponding folding mechanism the freezing material slides outward on the retrieval rake through the retrieval opening e.g. on a conveyor belt running in front of the retrieval opening below to extract the frozen freezing material.

Loading the baskets at the loading opening arranged thereunder can also be partially or entirely automated in that the freezing material to be frozen slides from a conveyor belt through a slanted slide respectively directly into a free basket behind the loading opening.

Due to the different dimensions of the freezing material the process is advantageously performed manually since a completely unmanned operation without manual monitoring can cause difficulties.

The freezing material to be frozen is therefore conveyed in storage containers or continuously on a conveyor belt proximal to the loading opening where the operator removes the freezing material and moves it into the freezing basket.

This can be facilitated in that a portion of a lower edge of the freezing opening includes an approximately loading table at the freezing basket onto which the freezing material to be frozen is placed. Using a handle the freezing material can be subsequently moved through the loading opening manually or also motor driven so that the freezing material only has to drop over the loading edge of the loading table backward into the basket.

This can also be performed in an automated manner through a respective folding or tipping device that automatically tips the freezing material into the basket as soon as the loading tablet has reached the respective position.

When the loading opening and in particular the loading table is arranged at hip height of the operator the operator can move the loading tablet forward even without hands with a hip movement and can already grip the next product to be frozen with the hands.

In order to minimize cold loss during loading and unloading the loading openings and unloading openings can be closed by flaps that open only during loading and unloading, advantageously controlled by a light switch which is triggered by the arrival by a new freezing material, the loading tablet or by the hand of the operator from an inside or from an outside depending on the opening or manually by a switch.

Instead of a fixed flap also a foil curtain can be used, advantageously a strip curtain or only a cold air curtain without mechanical separation wherein cold air moves top down in an interior of the housing directly behind the loading and unloading openings.

Advantageously, a flap will open in the retrieval opening in the outward direction, in the loading opening however in the inward direction, wherein the arrangement and size has to be selected so that no collision with the baskets can occur in an interior or with the conveyor belt on the outside.

The baskets circulate in an interior of the housing of the freezer wherein the evaporator is typically arranged on a large surface on the top side of the freezer in that the baskets are connected at both sides respectively with a tension element that continues through all baskets, for example a chain which is driven along typical sprockets in the circumferential direction, the movement direction of the baskets wherein a sprocket is driven on each side.

In order to use the space well in an interior of a for example cuboid housing the baskets revolve in the housing in a side view in vertically extending loops.

Another option that is not according to the invention is to not mechanically fixate the baskets at each other but to slide them along supports in inner surfaces of the side walls which, however, can require greater mechanical complexity than the solution with the tension element depending on the number of directional changes in an interior of the housing. It is an advantage to dismount the loose baskets respectively individually without any problem from the tension element so that the baskets can be retrieved when damaged or overall all baskets can be replaced more easily with basket with other dimensions, e.g. different height.

It is an essential problem of such freezers that they need to be cleaned quite frequently since all contaminations in the form of meat fibers or similar have to be removed reliably for hygiene reasons. Also in the distances and gaps between the prongs, optionally in the chain links etc.

For this purpose the baskets including the tension element and the pulleys and drive sprockets running the tension element are arranged in a slide which fills essentially an entire interior space of the housing of the freezer and which covers after opening a door, for example the front door which in turn covers an entire surface of the side so that the slide can be run out of the housing on rails and can be conveniently cleaned outside of the housing by a high pressure cleaner. Also the freely accessible interior of the housing can be cleaned easily.

According to the invention the loading opening and the retrieval opening are also arranged in the front door through which the slide can be run out.

The prongs of the baskets are made from a plastic material, advantageously polypropylene (PP) at the contact surface towards the freezing material wherein the plastic material has good heat conductivity. Advantageously the prongs and optionally the entire basket are entirely made from such plastic material.

Thus the contact surface with the freezing materials is advantageously selected larger than the stability determining remaining cross section of the prongs and in particular the cross section of the prongs is configured so that it has a relatively large surface while still being easy to clean.

Through the large surface the plastic material is quickly cooled down to the temperature of the cold air in the freezer and passes this temperature level to the contacted freezing material more quickly than the air itself which has much lower heat conductivity. A full surface contact of the freezing material on a continuous contact surface in the basket could easily cause freeze sticking of the freezing material and problems during unloading and in particular could prevent the described automatic retrieval by a retrieval rake. c) Embodiments

Embodiments of the invention are subsequently described in more detail with reference to drawing figures, wherein: FIG. 1 illustrates the freezer in the a cross section; FIG. 2 illustrates the freezer in a front view; FIG. 3 illustrates the freezer in an enlarged detail view; FIG. 4 illustrates two operating conditions in a perspective view: and FIG. 5 illustrates details of a basket.

The basic principle of the chain driven freezer is best illustrated in the sectional side view according to FIG. 1.

Within a temperature insulated closed housing 5 under whose ceiling the large evaporator 22 is arranged that generates refrigeration, a plurality of baskets 2a, b revolves in a movement direction 10 which is defined by the path of two endless chains 6a, b that revolve in parallel at a distance from each other wherein the tub shaped baskets 2a, b are arranged in the transversal direction 11 between the chains 6a, b.

The baskets are suspended at each face at an elevated, in particular highest point as a suspension point 29a, b at a chain link so that they are suspended independently from the instant horizontal or vertical orientation of this chain link following gravity with the open side of the basket 2a, b in upward and in forward direction towards the loading opening 3 and the retrieval opening 4 which are arranged in the front door 8.

Thus, the freezing material 100 illustrated as a pork chop strand of a pig can be inserted into a basket 2a... and circulates with the basket through the freezer 1 whose inner temperature is far below O9 C so that the freezing material 100 is surface frozen in a short time period. The prongs are made from a no stick material with good heat conductivity, in particular a plastic material (PP) and have a cross section in which the contact surface for the freezing material 100 is greater than the portions of the cross section oriented away from the freezing material in order to assure good heat conductivity between the freezing material 100 and the prongs 13a, b of the baskets 2a..., e.g. a double T cross section as illustrated in FIG. 3b.

The chains 6a, b and the baskets 2a, b run under the bottom side of the evaporator horizontally forward in a direction of the front door 8 and directly on the inside of the front door 8 vertically downward, are deflected up again by a lower pulley 23 and are subsequently run in vertical loops over the available height in the housing 1 in an alternating manner upward and downward so that the interior of the housing 5 that is available for the baskets 2a, is filled to a large extent by the baskets 2a...

At least one of the pulleys is configured as a drive sprocket 24 and connected with a motor 25 which is controlled by the control of the freezer like the entire control electronics in the operating panel 27 on an outside of the front door 8 is arranged above the loading and unloading openings 3, 4.

As illustrated in FIG. 1 and in particular the detail enlargement of FIG. 3 the retrieval opening 4 is above the loading opening 3 since the baskets filled with the frozen freezing material 100 that arrive behind the front door, e.g. 2d approach from above.

The freezing material arranged therein is automatically force retrieved at the retrieval opening 4 in that a retrieval rake is arranged from the inside of the front door 8 at a lower edge of the retrieval opening wherein the retrieval rake protrudes with its freely terminating prongs 19a into an interior of the freezer, thus far enough into the movement path of the baskets arriving from above, e. g. 2d so that the prongs 13a, ... of the baskets 2d... freely terminating in forward direction towards the retrieval opening 4 run from the top down between the fixated prongs 19a,... of the retrieval rake 20.

Since the prongs 19a,... of the retrieval rake 20 thus reach close to the back contact surface 2’ of the baskets 2d,...and the prongs 19a, b of the retrieval rake 20 have a top side that slopes downward towards the retrieval opening 4 the freezing material 100 when running through the basket e.g. 2d does not only stay put on the prongs 19a, b of the retrieval rake 20 but slides along on the retrieval rake 20 through the retrieval opening 4 out the housing 5 of the freezer 1 and remains in a catch tub that is attached in front of the retrieval opening 4.

From there it is manually removed by the operator and placed in a box, by the same token as illustrated in the perspective view 4a of the freezer 1 a conveyor belt 21 can run directly under the retrieval opening 4 instead of the capture tub 28 onto which the freezing material 100 drops automatically and is transported away.

The retrieval opening 4 is typically closed by an outward opening flap 12a that is linked above the retrieval opening 4 and is only opened by passing the freezing material 100 through since it otherwise hangs in the closed position following gravity.

After the baskets 2d have run through the retrieval rake 20 top down they are empty and can be filled with new freezing material 100 which is performed directly below at the loading opening 3.

The loading opening 3 is typically also closed and is released by a flap 12b that is also linked above the opening 3 wherein the flap 12b opens in inward direction for introducing the freezing material as illustrated in FIG. 3.

The freezing material 100 is thus placed on a loading tray 15 outside of the loading opening 3 and is pushed through the loading opening 3 by a slider handle 17 that is move able along guides 16 on the loading tablet 15 by the user manually or motor driven, as soon as an empty basket, e.g. 2a is arranged in the suitable position slightly below the level of the loading tablet 15.

Also this flap 12b closes in turn gravity induced and is only opened by the contacting freezing material 100.

The revolving chains including the baskets, the pulleys 23 the drive sprockets 24 and the drive motor 25 and the retrieval rake are mounted on a frame which can be run in forward direction out of the housing 5 of the freezer 1 on rollers configured as a slide 7 with the entire slide on rails 9 as long as the front door 8 is opened for this purpose.

The rails 9 on which the slide 7 runs can be pull out rails and can run with the slide 7 out of the housing 5, advantageously, however, they are separate rails 9 placed before extraction in front of the housing on supports and which are integrated in a rail frame.

The front door 8 can advantageously not only be pivoted open by 90s as illustrated in 4b, but by 180s so that maintenance and in particular cleaning work can be performed at the run out slide 7 and the mechanism arranged therein from all sides which is typically necessary once a day during continuous operation since all meat fibers and other contaminations typically have to be removed by high pressure cleaner from the intermediary spaces at the baskets, chains and other mechanical components. FIGs. 5a and b illustrate details of a basket: FIG. 5b illustrates an individual prong 13a in a side view wherein all prongs have an identity L shape with an intermediary angle between the arms of the less than 90s, advantageously approximately 80s which forms the lower and rear contact surface for the non-illustrated freezing material 100. In the approximately vertically extending rear arm of the prong there is a backward open undercut recess 30 which is used for lining up the prongs 13a... at a rail that extends in the transversal direction 11 of the freezer 1, thus the longitudinal extension of the basket.

As illustrated in FIG. 5a, the prongs have an approximately double T-shaped cross section in a portion of their lower receiving surface and of the rear arm wherein the contact surface for the freezing material can be slightly cambered upward in this cross section.

In order to further improve stability of the individual prongs additional struts are arranged along the prongs in particular where the prongs are bent.

REFERENCE NUMERALS I freezer 2a basket 2’ rear contact surface 3 loading opening 4 retrieval opening 5 housing 6a,... chain 7 slide 8 front door 9 rail 10 movement direction II transversal direction 12a,... flap 13a,... prong 14 contact surface 15 loading tablet 16 support 17 slide handle 18 pivot device 19a... prong 20 retrieval rake 21 conveyor belt 22 evaporator 23 pulley 24 drive sprocket 25 motor 26 photo electric sensor 27 operating panel 28 catch tub 29a, b suspension point 30 recess 100 freezing material 101 operator

Claims

1. Freezer cabinet (1) with - a heat-insulated housing (5), - several baskets (2a, b ...) running around the interior of the housing (5) in a carriage and containing the frozen items (100), in particular - a filling opening (3) in the housing (5), - a withdrawal opening (4) in the housing (5), where - the filling opening (3) and the withdrawal opening (4) are arranged on the same side of the freezer (1) above each other in the housing (5), - the housing (5) has a front door (8), and - the filling opening (3) and the withdrawal opening (4) are arranged in the front door (8), characterized in that - the curves (6a, b) in both sides are each connected to a traction element passing through all baskets - the carriage (7) after opening the front door (8) can be completely driven out of the housing (5), especially on rails (9), including all baskets (6a) , b) and the at least one pulling element and its redirection tip wheels (23) and drive wheels (24) and drive motor (25), - a filling tray (15) extends through the lower edge of the filling opening (3), on the upper side of which a slide grip (17) on guides (16) from a position outside the filling opening (3) can be moved to a position within the filling opening (3) near the rear positioned basket (2a), - the sliding handle (17) of the filling tray (15) and thus the filling opening ( 3) is placed at hip height by a user (101) standing in front of the freezer (1).

Freezer cabinet (1) according to claim 1, characterized in that the baskets (2a, b ...) are connected to each other by at least one pulling element connecting all baskets (2a, b ...), in particular at least one chain (6a), and in particular there are two pulling elements, in particular chains (6a, b), each connecting all curves (6a, b ...) in each one of the two front ends with each other, or the curves (6a, b) are not connected to each other and pushed along guides (1b) in the interior of the housing (5).

Freezer cabinet (1) according to one of the preceding claims, characterized in that the openings (3, 4) are closed by each a separate or a common flap (12a ...), the flap (12a) at the opening (4) opens outwardly, and especially by gravity, is held in a closed position and pressed up from the inside as a frozen workpiece (100) approaches.

Freezer cabinet (1) according to one of the preceding claims 1 and 2, characterized in that the openings (3, 4) are constantly open and have no door and on the inside are thermally shielded relative to the interior of the housing (5). cold curtains of cold air flowing from the top down the width of the openings (3, 4).

Freezer cabinet (1) according to one of the preceding claims, characterized in that the openings (3, 4) are arranged in a vertical wall of the front door (8), with the withdrawal opening (4) above, especially directly above, the filling opening (3) and the curves (2a, b ...) directly behind these openings move vertically from top to bottom, and / or the curves (2a, b ...) upwards and especially towards the openings (3, 4) are open.

Freezer cabinet (1) according to one of the preceding claims, characterized in that the curves (2a, b ...) are seen in the longitudinal direction, ie. transverse (11) to the direction of movement (10) of the curves (2a, b ...), has an L-shaped cross section and consists of individual teeth (13a, b) arranged in the longitudinal direction one after the other, and which, at least at their contact surfaces towards the frozen workpiece, is made of plastic, in particular polypropylene.

Freezer cabinet (1) according to claim 6, characterized in that the teeth (13a, b) have a cross-section where the contact surface towards the frozen part (100) is wider than the rest of the cross-section, and the teeth (13a, b) thereby in particular. is designed so that the surface of the cross-section is as large as possible, especially near the contact surface towards the frozen workpiece (100).

Freezer cabinet (1) according to one of the preceding claims, characterized in that the sliding handle (17) has a motor drive.

Freezer cabinet (1) according to one of the preceding claims, characterized in that - the filling tray (15) comprises a tilting device (18) which tilts the filling tray (15) inwards downwards to the rear basket at approximately the rear position thereof lying basket (2a) so that the frozen item (100) automatically slides into this basket (2a).

Freezer cabinet (1) according to one of the preceding claims, characterized in that - there is fixedly mounted on the inside of the take-out opening (4) a take-out tear (20) whose teeth (19a, b) pass through the free distances between the teeth of the the basket (2a, ...) extending from the top and down the rear and the openings automatically take the frozen item (100) out of the basket (2a, ...) and the take-out tear (20) has an inclined downward inclination, so that the frozen article (100) by gravity slides outwardly through the take-out opening (4) via the take-out tear (20), and / or - on the outside of the fill-in opening (3) and / or the take-out opening (4) a conveyor belt (21a) is arranged. ) for feeding and removing the frozen item (100) and the frozen item (100) at the take-out opening (4) automatically slides from the take-off tear (20) directly to the associated conveyor belt (21a).

Freezer cabinet (1) according to one of the preceding claims, characterized in that - an evaporator (23) is arranged on the upper side of the freezer cabinet (1), and / or - the at least one pulling element, in particular the chains (6a, b), viewed from the side of the freezer cabinet (1) with the baskets (2a, b) running meander-shaped upwards and downwards in the freezer cabinet (1), and on each of the circumferential tensile members, a clamping element, in particular a chain tensioner, is arranged for temperature and wear-related length equalization of tensile member.