SE527370C2 - Freezer furniture and effort for this - Google Patents

Abstract

In a first aspect, the invention relates to a piece of freezing furniture comprising a storage space ( 3 ), intended for products to be frozen, and a primary air duct ( 4 ), which partly surrounds a suction duct ( 11 ), having an inlet ( 12 ) that mouths at one side of the opening ( 13 ) of the storage space ( 3 ), as well as a rising duct ( 14 ), having an outlet ( 15 ) that mouths at the opposite side of said opening ( 13 ), and a temperature-change unit ( 36 ), which is located in the primary air duct ( 4 ) and separates the suction duct ( 11 ) from the rising duct ( 14 ) and includes a fan ( 16 ), a heating element ( 17 ) and a cooling element ( 18 ), wherein, in normal operation, cooled air flows from the temperature-change unit ( 36 ) via the rising duct ( 14 ), over and past said opening ( 13 ), through the suction duct ( 11 ) and back to the temperature-change unit ( 36 ). In a second aspect, the invention also relates to an insert for such a piece of freezing furniture.

Description

20 25 I.

Q I .O: OULQ O coon 0 .... .gg nbco Q I oo 000 gg 00 00 0 Q I O 9 I I I I I I I no 0 I V! nu c nu 0 n 0 o u n 0000 n n 0 A 0 | n 0 u I c 9 o nous 0 noe ol I 0 oo. a n v c 9 u nun 0 527 370 2 0 0 of freezer furniture with circulating cooling air, it is inevitable that the cooling air is mixed with the surrounding shop air, as the cooling air flows past the opening of the freezer furniture. The ambient air has a higher humidity, which means that the cold, circulating air is continuously supplied with a large amount of moisture when the air masses are mixed. The moisture condenses in the air duct and is mainly deposited on the cooling element in the form of hoarfrost or ice and will thus interfere with its cooling function. In order to remove the hoarfrost / ice and thereby maintain a good cooling production, it is required that the cooling element of the freezer unit is frosted off either at regular intervals or when the need arises.

To defrost the cooling element, one or more heating elements are used, which are often located upstream of the cooling element in the air flow direction. According to previous defrosting methods, the fan continues to circulate the air via the same air duct as in normal operation, but during defrosting the heating element is activated at the same time as the cooling element is switched off.

The air is thereby heated to plus degrees, whereby the ice on the cooling element and on other surfaces melts. The melt water that is formed is collected and allowed to flow out via a drain pipe located in the bottom of the freezer unit and on to, for example, a floor drain. A major disadvantage is that the entire circulating air mass must be heated to plus degrees in order to have the most efficient defrosting possible. The goods in the storage compartment will consequently be exposed to air temperatures exceeding 0 ° C during much of the defrosting process. It has been shown that even a short-term, applied heat shock on the surfaces of a product can be very harmful, as it is propagated throughout the frozen product even if cold is added to the surfaces again. All the air circulating in conventional freezer furniture may, as a result of the air being heated, at the final stage of a defrosting process be substantially saturated with moisture. This moisture will immediately after initiated cooling production condense and be deposited on the coldest surfaces, which is the cooling element, in the form of hoarfrost or ice and will thus interfere with its cooling function. Accordingly, if ice forms on the cooling element immediately after a defrosting process, then a Q I n. I »oooo s non .gïøon En! 090 'oc cool / I' lo O I g 0 c 000 a co II. .g al 0 I nu I .o 01 0 00 527 370 3 defrosting has to some extent been unprofitable. Even the goods that are placed in the storage space are still so cold at the final stage of defrosting that the moisture-saturated air on contact with the goods will be deposited on them. This causes the awkward inconvenience that when the goods are selected by a customer and transported through the store in a cart, the ice will melt and soak everything else in the cart.

Defrosting according to this technique usually takes place before the store opens and after the store has closed, as the store owner does not want customers to buy goods with a partially elevated temperature. An elevated temperature means that the goods experience a shortened time window, during which they should be transported out of the store and on to the home without risk of being disposed of. If defrosting occurs before the store opens and after the store has closed, the goods will maintain a satisfactorily low temperature during the time they are exposed to the customers. Due to long opening hours in a store, up to 12 hours or longer, a lot of moisture has time to be deposited on the cold surfaces of the freezer furniture, which is one reason why each defrost can take a long time, often 0.5-l hour per occasion. In addition to the food being exposed to harmful temperatures, it is also very energy-intensive to heat and cool the entire large circulating air mass, as described above, and to cool the circulating air during normal operation if the cooling element is ice-covered.

In order to solve the problem, to allow hot air to circulate around the entire storage space 1-2 hours a day and thereby damage the food, many attempts have been made to allow the hot air to flow during defrosting via other ducts than those in which the cold air flows through during normal operation. Freezer furniture with defrosting devices based on the use of a bypass duct are already known from, inter alia, the documents DE 1, 75l, 73l, DE 19,810,0232 A1, and DE 19,844,854 A1.

In the first-mentioned document (DE 1, 75l, 73l) a defrosting device is presented, which uses a 10 15 20 25 30 90 QI 0 I DIGI .. .fl .. ....: Û-Ü zz:: .nu_ ) oc: Qcc. aloe ', ... | .. onn fl h I! 00 '0 0000 OQO g 0 I O 527 3704 n 0 Qcca Q 0 oo I OI Û 0 00. 0 novnbt 0 p 0 now 0 0 oo bypass duct located in the air duct.

The bypass duct is open at both ends, during both normal operation and during defrosting, which means that a large amount of the cooled air during normal operation will take the short, easy path through the bypass duct and only circulate under the freezer storage space. During defrosting, the direction of rotation of the fan changes and a damper closes the suction duct, whereupon the air flow is forced through the bypass duct, the outlet opening of which opens into the riser duct. Since hot air has a lower density than cold, the heated air flow leaving the bypass duct will rather rise through the riser than sink to the temperature exchange unit, while cold air will be drawn down through the riser in exchange for the hot, rising air. If defrosting takes place during the store's opening hours, the goods will be exposed to a rise in temperature, as in the previously known technique described above. The device presented thus does not provide an efficient defrosting method and a deteriorated circulation of cooled air during normal operation.

The latter two publications (DE 19,810, 232 A1 and DE 19,844,854 A1) also show the devices comprising bypass ducts located in the air duct.

Unlike DE 1, 751, 73l, each of these writings shows that one end of the bypass duct can be opened and closed by means of a damper, whereby cooled air is forced to pass through the ordinary air duct in normal operation. Furthermore, the inlet of the suction ducts and the outlet of the riser ducts are provided with dampers, which are closed during defrosting at the same time as the damper of the bypass ducts is opened. The hot air can thus only circulate through the bypass duct during a defrosting process, but since the dampers in the suction ducts and the riser ducts are located at their inlets and outlets, the latter ducts will also be filled with hot air during defrosting, consequently there is still a very large air mass should be heated.

Furthermore, in normal operation it is extremely important that the air flow leaving the outlet of the riser is not too 10 15 20 25 It Q O .O OIIIÉ Of.

'°; : '°; ° ': °' III § .._ .... o o..c .lf-å .. '..- s27 370 5 .fi -..-, -J._T% o oot0 o qnoo o go o, onv 0, nu .o .uoon 1 us un o nu 0 oao; o turbulent and that the same leaves the outlet at a certain angle, in order to reliably flow over and past the opening of the storage space to the opposite side. In the inlet of the suction duct, it is similarly important that nothing disturbs or prevents the air flow from being sucked down into the duct.

Thus, as shown in said publications, it is not very functional to place a plurality of coarse dampers in these places.

The dampers can even cause the cooled air to mix with the surrounding shop air to a greater degree than before.

The dampers in the devices shown may fulfill their functions during defrosting to an acceptable level, but risk creating large operational disturbances during normal operation.

OBJECTS AND FEATURES OF THE INVENTION The present invention aims at eliminating the above-mentioned disadvantages of previously known freezer furniture and creating an improved freezer furniture. A primary object of the invention is thus to create a freezer unit which can be frosted whenever the need for defrosting arises without heating the goods stored in the storage space by heating and thereby creating inconveniences for the customers. It is also an object to create a freezer unit that does not interfere with the air flow during normal operation and which thereby ensures good function. An additional purpose is to create a freezer unit, which saves energy through efficient defrosting. A further object is to create a freezer unit with a defrosting device in the form of an insert that can be installed in an existing freezer unit. It is also an object to create a freezer unit with a defrosting device which includes few moving parts, in order to minimize the risk of them freezing during normal operation. At least the primary object is achieved by means of the initially defined freezer unit, which is characterized in that it comprises an insert located in the primary air duct, which comprises a secondary air duct with partly an inlet opening, which opens into the primary air duct opening downstream and and closable by means of a damper, on the one hand an outlet opening, which air duct opens upstream into the H1 temperature exchange unit and at which a control means is arranged, with the task of controlling the air flow leaving said outlet opening, in direction against the temperature change- In the unit and on the outside of the insert towards said inlet opening.

Advantageous embodiments of the invention are further apparent from the dependent claims 2-7, as well as from the following, detailed description.

In a second aspect, the invention also relates to an insert, which is characterized by the features stated in the characterizing part of the independent claim 8. Brief description of the accompanying drawings In the drawings: Fig. 1 is a perspective view of a freezer unit, Figs. Fig. 2 is a cross-section of a freezer unit according to the invention, Fig. 3 is an enlarged, cut detail view of the damper in a first position, Fig. 4 is a detailed view of the damper corresponding to Fig. 3 in a second position, Fig. 5 is an enlarged, cut detail view of an alternative embodiment of the damper in the first position, Fig. 6 a detailed view of the damper in the second position corresponding to Fig. 5, “Fig. 7 an enlarged, cut detail view of a further alternative embodiment of the damper in the first position, and Figs. 8 is a detail view corresponding to Figure 7 of the damper in the second position.

Detailed description of preferred embodiments of the invention Figure 1 shows a conventional freezer unit 1, of the type used in the retail trade for storage and supply of frozen and frozen foods 2. In the example shown, the freezer unit 1 consists of a single freezer gondola, but also double freezer gondolas , freezer shelves, freezer counters, etc. are included in 10 15 20 25 oc an. : con. '°. q .ba ..,. 0 ,. .. u) .avi co uno ° "'S ICO! Ido 527 370, .. the concept of freezing furniture.

Reference is now also made to Figure 2. The freezer furniture 1 shown comprises a storage space 3, which is open upwards for a customer to have unhindered access to the goods placed in the storage space 3, and thus offered, Furthermore, the freezer furniture 1 comprises a whole with 4 denoted large, primary air duct, which is delimited inwards by the walls 5, 6 and floor 7 of the storage space 3 and outwards by the outer walls 8, 9 and bottom 10 of the freezer furniture 1. at one side of the opening 13 of the storage space 3, and a riser 14 with an outlet 15, which opens at the opposite side of said opening 13. A temperature change unit 36 is located in the primary air duct 4 and separates, or forms a boundary, between the suction duct 11 and the riser. In other words, the primary air duct 4 has a suction side and a riser side, which are separated by the temperature change unit 36.

Temperature switching unit 36 comprises a fan 16, a heating element 17 and a cooling element 18, which are placed one after the other in the primary air duct 4. It should be pointed out that both the heating element 17 and the cooling element 18 can be constituted by one or more sub-elements without affecting the inventive concept. Analogously, the fan 16 can also consist of one or more sub-fans. Their mutual placement is also of no significant importance for the joint task.

During normal operation, i.e. during cooling production, the heating element 17 is inactive and the cooling element 18 active, the fan 16 creating an air flow which is cooled by the cooling element. The cold air flow is circulated via the riser 14, over and past the opening 13, down through the suction duct 11 and back to the temperature change unit 36. Because cold air has a higher density than hot, the cooled air will sink by its own weight into the storage space 3 and thereby 527 m 8 -: 1 = cool the goods 2, and form a "lid" in the opening 13 towards the I '' ÅA lr fl- IW-æ + 11Io111F + An mmm fifl vïrnïnv - wvs turned. varma bnt. “-. n..tH-” Én u ... n.r.nHHe .n..å '111-F + - ^ v \; | _. | In this case, the storage space 3 and the goods 2 also cool, when the same is located in the riser 14 and the suction duct 11, namely via the walls 5 and 6, which are preferably made of thin sheet metal or glass.

Although the cold air in the storage space 3 is heavier than the store air, a mixture still occurs between the two air masses 10 due to the turbulence that occurs in the air in the store when customers pass the freezer furniture 1 or pick up goods 2 from it. When the hot air, which contains more moisture than cold air, accompanies the air mass circulating in the freezer unit 1, the supplied moisture will condense and be deposited on the cold surfaces in the primary air duct 4 in the form of hoarfrost and / or ice. This takes place primarily on the cooling element 18 and its flanges. The smallest deposit of ice on the cooling element 18 affects the cooling production in a negative direction, with extra energy consumption as a result and a risk of relatively high temperatures on the circulating air mass.

In order to initiate defrosting of primarily the cooling element 18, but also other cold surfaces in the primary air duct 4, a signal thereon must be obtained. This signal can, for example, be given manually or automatically when the need arises and / or at regular time intervals. The defrost signal activates the heating element 17 and at the same time the cooling element 18 is deactivated.

The initiation signal also affects a damper 19, which opens a secondary air duct 20. The fan 16 also continues during defrosting to circulate the now hot air in the same direction as the cold air is circulated in during normal operation, but through the short secondary air duct 20. instead if; for the long, primary air duct 4. The secondary ff; the air duct 20 comprises on the one hand an inlet opening 21 which can be opened and closed by means of the damper 19, which opens into: the primary air duct 4 downstream of the temperature exchange unit 36, and on the other hand an outlet opening 22, which opens into the primary air duct upstream. temperature change- 10 15 20 25 IQ OC «. ' u: coca o 00 'bt. '00. : '°' z .u_ ,. an .. anno ... uza fl linl ICO 527 370 9 o o o n n n ad u n o u nu,. a v 'z f: un: v In the device. When the damper 19 opens said inlet opening 21, it simultaneously closes the riser 14 between the wall 5 and the wall 8. In other words, the damper 19 is movable between a first position, in which the inlet opening 21 of the secondary air duct is kept closed and the riser 14 of the primary air duct is kept open. and a second position, in which the inlet opening 21 is kept open and the riser 14 is kept closed.

Due to the damper 19, during defrosting, the air flow is forced to flow via the short path through the secondary air duct 20 and towards its outlet opening 22. At the outlet opening 22 a control means or a baffle 23 is arranged, which forcibly controls the air flow leaving said outlet opening 22. the temperature exchange unit 36 and towards said inlet opening 21. The baffle 23 extends into the primary air duct 4 and forward in the air flow direction, more specifically towards the temperature exchange unit 36.

In a preferred embodiment, the baffle 23 is slightly bent so that its free end points in the direction of the temperature change unit 36 to smoothly direct the air flow in the desired direction, but the baffle 23 can also be made of a flat disc extending obliquely inwards / forwards. It should be pointed out that the distance between the free end of the baffle 23 and the bottom 10 should be at least as large as the width of the suction duct 11, which means that the baffle 23 does not interfere with the air flow during normal operation. Although the air circulated via the secondary air duct 20 during defrosting is hot and thus has a lower density than the still cold air, which is stationary in the suction duct 11, the design of the baffle 23, the fan 16 and the mass inertia of the air cause little or no hot air to disappear. rises through said suction duct 11. The shorter path that the air has to pass during defrosting means that less air must be heated than with previously known devices, which gives energy savings. When the ice melts, melt water is formed, which is led to a drain pipe 24, which is located in the bottom 10 of the freezer furniture 1, and further to, for example, a floor drain in the store (not shown). 10 15 20 25 I b) C pa coon I 'g n 0 Û 0 oo: etc. ecco -0.:. ä ,, .., øooo c 0 00 'Û °°. ,. u 90 Il I n vego no I o ooocø! 00 I oo 0 90 0 '527 370 10 gif., ..

Defrosting continues until a cooling production signal is given manually or automatically after work has been completed and / or after a predetermined time. The cooling element 18 is then activated again and at the same time the heating element 17. The cooling element 17 is given. time after the signal has been given or until the air has cooled back to the desired level.

A freezer unit 1 should for the most part of its length comprise a secondary air duct 20 in order to obtain an effective defrost. Preferably along more than 75% of its length, most preferably more than 85%. Those parts of the length of the freezer unit 1 which do not include a secondary air duct 20, due to supporting struts and / or other components, must be sealed at the lower part of the riser 14, both during normal operation and during defrosting, so that cooled air does not take it shorten the path via the secondary air duct 20 or that hot air should rise through the riser 14.

Reference is now also made to Figures 3 and 4. In a preferred embodiment, the damper 19 is movable between the first position and the second position by being pivotable about a joint 25. The damper 19 consists of a damper plate 26 and a sealing strip 27. Said joint 25 is formed of a flexible material 28 extending between a mounting plate 29 and the damper plate 26. The flexible material 28 may have a waist or a guide for facilitating pivoting of the damper 19. The flexible material 28 may be for example a plastic or a preferably airtight textile , which in the event of defrosting can contribute to sealing the riser 14. In the first position of the damper 19 the sealing strip 27 closes the inlet opening 21 to the secondary air duct 20. In the second position of the damper the sealing strip 27 abuts the wall 8, and the damper plate 26 shields most of the riser 14 and the flexible 10 15 20 25 'II Û .C oooo UJ G o'. oo. .o0. Olä U 'O o oo no oo oo oo 00 0 I IC .O C OO I O I OO OQO o o o oo oo poooo O n. o7 oo coon o .oo o o 527 370 the material 28 seals between the damper plate 26 and the wall 5, either directly or via a spacer 30.

The damper 19 is actuated by a spring 31, which always strives to keep the same in said first position. Arranged between the damper plate 26 and the wall 5 is one or more flexible bladders 32, which can be filled with a pressurized fluid from a fluid source connected thereto to bring the damper 19 to said second position in the filled state. The access of the fluid to the bladder (s) 32 can be controlled, for example, by a valve (not shown), (not shown), which is activated by the defrosting signal described above or as a consequence thereof.

The bladder 32 can be made by extruding, for example, a plastic and can, in addition to a cover for the fluid itself, also include a lip (not shown), which is fixed under the mounting plate 29, so that the bladder 32 is not forced out of place when it is filled. Each bladder in an air-permeable bag (not shown) is fixed under the mounting plate 29. The bag must be air-permeable as it will not rupture the bladder 32. In the embodiment shown in Figures 3 and 4, the bladder 32 is fixed to the damper plate 26 and the wall 5 by means of an adhesive or a double-sided adhesive tape. The bladder 32 may consist of a plurality of sub-blisters separated along the length of the freezer furniture 1, each of which has a small extent or of a smaller number of elongated sub-blisters. In the case of a plurality of sub-blisters, the springs 31 should be arranged opposite them so that the damper 19 is not bent along its length and thus does not fully perform its function. 32 can also be housed, the upper part of which in this case may expand itself. Now reference is made to Figures 5 and 6. In this alternative embodiment, the damper consists partly of a plate 33, which is preferably made of a relatively rigid plastic, and partly of one or more flexible blisters. 32. Also in this alternative embodiment, the plate 33 can preferably be provided with a waist or instructions, at which it can be bent. A part of the plate 33 is attached to the wall 5 and a part is arranged to close the inlet opening 21, when the damper is in it. On the side of the plate facing the riser 14, the flexible bladder 32 is arranged by an adhesive or a double-sided adhesive tape. Said bladder 32 is fillable with a pressurized fluid as described above. When the bladder (s) 32 is in the unfilled state, the inherent rigidity of the plate 33 tends to move the damper towards the first position and in the filled state the inlet opening 21 is opened while the bladder 32 abuts the wall 8 and thus closes the riser 14. It should be noted that the the flexible bladder 32 must extend along the entire length of the riser 14 of the freezer to be closed during the defrosting process, in order to achieve the required seal. first mode.

Reference is now made to Figures 7 and 8, which show a further alternative embodiment of the damper. In this case, the damper is movable between the first position and the second position by being slidable at an angle to the riser 14, for example by means of a piston-cylinder mechanism 34. The displacement of the damper can also take place with, for example, a rack, a belt drive or the like. When the damper is in the first position the damper plate 26 overlaps the inlet opening 21 and when the damper is in the second position a sealing strip 27 seals against the wall 8 at the same time as the damper plate 26 shields the riser 14 and as a number of holes or openings in the damper plate 26 align with the inlet opening 21.

Installation of the insert according to the invention in an existing freezer unit The insert according to the invention is easily installed in an existing freezer unit 1. These freezer units 1 probably have no dampers or secondary air ducts but the air circulates the same way during defrosting as during normal operation. In the following description, reference is made to Figures 1 to 4, which show a preferred embodiment of the invention. Similar reasoning can, however, be made for alternative embodiments of the damper 19. 10 15 20 25 527 370 13 0:10. : co =: Én * v fifl- i-i- fi '^ v \ n'11 3 :; | | n \. ||| \ 1 | n. || 11 I 5 a J W w FJ |, -l ncomprehends the number of transverse sections along its length. The freezer unit 1 in figure 1 comprises six pieces, but it should be understood that the number of sections can be larger as well as smaller. Often each section comprises its own separate floor plate or a floor 7. Each floor plate 7 rests on angular elements 35, which are arranged in the lower ends of the walls 5 and 6 of the storage space 3 and which extend in the direction of each other. The floor 7 is insulated or consists entirely of an insulating material, to protect the goods 2 from the hot air during defrosting. The desired number of base plates 7 is lifted out and corresponding parts of the wall 5 are dismantled from the freezer unit 1. Then the damper 19 is mounted on the side of the wall 5 facing the primary air duct 4, by means of a fastening element, for example a screw, a pop rivet, etc., which fixes the flexible material 28 between the mounting plate 29 and the wall 5. The bladder 32 is connected to a fluid source (not shown) which is installed in a suitable place adjacent to the freezer furniture 1. One and the same fluid source can serve one or more cross sections and / or freezer furniture 1. The fluid may be a gas, for example very dry air or a liquid, for example a suitable hydraulic oil. In the vicinity of the angle element 35, a number of holes or openings are taken up, along the length of the freezer unit 1 to be provided with the insert.

The holes or openings together form the inlet opening 21. The wall 5 is then reassembled in the freezer unit 1. The sections of the riser 14, which are not to contain an insert, are provided with shielding plates, which coincide with the damper 19 when it is in the second position, so that no hot air must be able to rise through the riser 14 during defrosting.

Wall 6 is completely unaffected by the renovation. The insert according to the invention is then placed on the angle elements 35.

The insert comprises a secondary air duct 20, which is formed by a box of rectangular cross-section. The floor 7 is then placed on top of the insert. The insert can also have a cross-sectional U-shape, with a relatively large bottom 37, in this case the secondary air duct 20 is formed only when the floor 7 is placed on top of the insert, in other words forms in 10 15 20 25 oo ooo I ooo fifi 3 oo oo oooo ooooo ooo til. to o 'loan n. ou UI 527 370 14 .gl the floor 7 the upper boundary of the secondary air duct 20 and the bottom 37 the lower. The insert is completely open at the end facing the riser 14, or holes or openings are provided, which fully or partially correspond to the holes or openings arranged in the vicinity of the angle element 35 in the wall 5. At the other end of the insert is an outlet opening arranged which consists of a number of holes or openings arranged in the bottom 37 of the insert, in the vicinity of the wall 6. In the immediate vicinity of this outlet opening 22 a baffle 23 is arranged, which forcibly controls the air flow in the desired direction.

Advantages of the invention A fundamental advantage of the freezer unit according to the invention is that it has a separate air duct for hot air during defrosting, which results in defrosting of the freezer unit whenever the need arises, without damaging the goods placed in the freezer unit by heating and thereby creating inconvenience to customers. An advantage of defrosting regardless of time is that cooling production and air circulation during normal operation can take place in a more efficient way, which leads to less energy consumption. Another advantage of the freezer unit according to the invention is that the hot air only needs to circulate a short distance during defrosting and thus a much smaller amount of air needs to be heated, which together with the circulating air not mixing with other air leads to a faster defrosting process and this higher efficiency provides energy savings. Another advantage of a smaller amount of air having to be heated is that a smaller amount of moisture can be taken up and thus precipitated at the initiation of cooling production.

Consequently, an energy-efficient defrosting process is obtained which is not harmful to the goods placed in the freezer unit.

Possible modifications of the invention The invention is not limited only to the embodiments described above and shown in the drawings. Thus, both 10 15 20 25 in OO .Q Iáiig ID OI OI o 0 oo 0 i Q 0 0 QI i 000 no 0 o 0 ',., .. g 0o 100 a I 0 O 527 370 15 - 0000 u 01 0 on 00 0000 000: n 0 no 0 u I 00 0 o 0 o 0 0 0 cc0000 o 0 n 0 uoco po0oo n 000000 o the freezer furniture as the insert is modified in all manner within the scope of the appended claims. For example, it is conceivable to let the damper be affected by a bimetal instead of a fluid bladder. A bimetal changes shape at a predetermined temperature and thus forcibly moves the damper from the first position to the second when the temperature rises above the limit value and back from the second position to the first when the temperature falls below the limit value due to restarted cooling production. With a well-chosen bimetal, the limit temperature can be set so low that the riser is closed at an early stage of the defrosting process and reopened only when the air mass circulating in the secondary duct has reached a sufficiently low temperature, so as not to be harmful to the goods. The damper control can also take place with a closed fluid-filled bellows, which is mounted on a hot plate, which is activated when the heating element is activated. The bellows' hotplate generates heat, which leads to the fluid in the bellows expanding and thus the bellows is given a movement that can be transmitted to the damper that closes the riser, or that the bellows itself closes the riser.

The fluid has an inherent cooling inertia, which means that when the heating plate is deactivated, a delay occurs before the bellows returns to its original shape. This time can be extended by the heating plate being active for a longer time than the heating element.

It should also be mentioned that the baffle or control means does not necessarily have to consist of a plate or disc, but may very well consist of a number of small fans or vanes, which control the air flow in the desired direction.

In the example shown in the drawings, the storage space is open upwards, but it should be pointed out that in the case of freezer shelves, for example, the storage space is open to the side, to allow access to the goods placed on the shelves. When defrosting freezer shelves and freezers, ie. freezer shelves with doors, it is extremely important that the hot air does not circulate along the same ducts as the cold air at normal 10 15 20 527 370 16 0 0 Q 0 tour co I.

In 0 0 0 ß operation, because the cold air, in addition to the circulating circulation, also flows along each shelf from holes located in its trailing edge to its leading edge. As a result of allowing hot air to flow in this conventional manner among the frozen goods, they are thus exposed to a high risk of being discarded due to the defrosting process. A separate duct for hot air means that this risk does not arise.

The fan in an existing freezer unit can also be reversible in such a way that it changes the direction of rotation at the transition between normal operation and defrosting. The insert is then inserted in reverse, ie the inlet opening of the secondary air duct opens into the suction duct and the outlet opening opens into the riser duct.

Finally, it should be pointed out that the drawings are not proportionate, but have a schematic character, and that there are also double freezer furniture with two separate suction ducts and a common riser duct. The outer wall of the individual freezer furniture riser is then replaced by a low wall that extends from the bottom of the freezer up to the riser to a height that is level above the point where the damper abuts it, when the damper is in the second position.

Claims (8)

10 15 20 25 30 35 527 370 17 Patent claims Freezer furniture comprising a storage space (3) intended for freezer goods and a primary air duct (4), which partially surrounds said storage space (3) and which inside (11), with an inlet (12) partly comprises a suction channel which opens at one side of the opening (13) of the storage space (3), partly a riser channel (14), with an outlet (15) opening at the opposite side of said opening (13), and a temperature change unit (36), which is located in the primary air duct (4) and separates the suction duct (11) from the riser duct (14) and including (16), (17) and a cooling element (18), whereby cooled air flows from temperature during normal operation, a fan grips a heating element and the turbulence unit ( 36) via the riser (14), over and past said opening (13), through the suction duct (11) and back to the temperature change unit (36), the latter comprising an insert located in the primary air duct (4), which comprises a secondary air duct (20) with partly an inlet opening (21), which opens into the primary air duct (4) downstream of the temperature exchange unit (36), and can be opened and closed by means of a damper (19), and an outlet opening (22), which opens into the primary air duct (4) upstream of the temperature exchange unit, characterized by , that the damper (19) is movable between a first position, in which the inlet opening (21) of the secondary air duct (20) is kept closed and the riser duct (14) of the primary air duct (4) is kept open, and a second position in which the inlet opening (21 ) is kept open and the riser (14) is kept closed, and that a control means (23) is arranged at the temperature change unit, with the task of controlling the air flow leaving said outlet opening (22), in the direction of the temperature change unit and on the outside of the insert towards said inlet opening (21). Freezer unit according to Claim 1, characterized in that the damper (19) is movable by being pivotable about a joint (25). Freezer unit according to claim 2, characterized in that the damper (19) is included in a damper device, which also comprises a mounting plate (29) and one (29) between the damper (19) and the mounting plate. stretching band (28), which is made of a flexible material and forms said joint (25). Freezer furniture according to one of Claims 1 to 3, characterized in that the damper (19) is actuated by a spring (31) which always strives to keep the same in said first position. Freezer unit according to one of Claims 1 to 4, characterized in that a flexible bladder (32) is arranged at the damper (19), which can be filled with a pressurized fluid from a fluid source interconnected therewith, in order to the damper (19) to said second position. Freezer unit according to one of the preceding claims, characterized in that the control means (23) is a baffle. Freezer unit according to one of the preceding claims, characterized in that the control means (23) extends in the direction from the outlet opening (22) of the insert into the primary air duct (4) and forwards in the air flow direction towards the temperature change unit (36). Insert for freezer furniture, characterized in that it comprises a secondary air duct (20) with partly an inlet opening (21), which can be opened and closed by means of a damper (19), and partly an outlet opening (22), wherein the damper (19) ) is movable between a first position in which the inlet opening (21) of the secondary air duct (20) is kept closed and a riser duct (14) of a primary air duct (4) in a freezer unit is kept open, and a second position in which the inlet opening (21) open and the riser (14) is kept closed, and that a control means (23) is arranged at the outlet opening (22), with the task of controlling the air flow leaving said outlet opening (22), in the direction of said inlet opening. (2l) .