DE9418978U1 - Ice cream maker - Google Patents

Description

The invention relates to an ice cream production machine according to the preamble of patent claim 1.

While the ice cream making machines most commonly used in practice work either with a vertically arranged rotating container into which a stirring tool can be inserted or with a horizontally arranged drum in which a horizontal agitator is located (DE-OS 22 59 278, DE-OS 39 38 904), whereby filling the liquid mass and cleaning are particularly problematic, ice cream making machines of the type mentioned at the beginning with an upright stationary container open at the top and a rotating agitator arranged in it are already known (EP-A-O 161 679; FR-A-2 558 688). Ice cream making machines of this type are particularly suitable for producing comparatively small quantities of ice cream in the range of 5 to 15 liters. They are easy to fill and clean. One problem with these ice cream making machines is, on the one hand, to achieve the fastest and most even mixing and freezing of the ice cream mass during the ice cream making process and, on the other hand, to get the ice cream out of the container relatively quickly and without great handling effort after it has been made.

In an ice cream production machine of the type mentioned at the beginning (EP 0 596 221 A1), the interior of the container is accessible from above over its entire cross-section because the drive shaft is pivotally mounted independently of any lid and in particular only in the area of the bottom wall, since the lid normally provided at the top can be completely removed or opened up since no pivot bearing is provided in it. The design of the agitator according to the invention ensures a constant and even flow in the

The circulation is carried out upwards in the area of the peripheral wall and axially downwards in the area of the rotation axis, whereby the ice cooled in the area of the peripheral wall or scraped off the peripheral wall and the base wall is guided upwards, radially inwards and then downwards again in a uniform flow. This circuit enables an extraordinarily large evaporator surface and rapid and intensive mixing and freezing of the liquid or dough-like ice cream mass. The result is not only optimal and even heat extraction in relation to all areas of the liquid mass, but also a freezing process that excludes local, larger-scale crystal formation. Due to the rotation of the stirring tool, the overall movement of the ice cream mass during production is screw-like. If the direction of rotation of the stirring tool is reversed after the ice cream has been made, movement components are generated in it that lead to rapid, intensive and largely complete ejection of the mass from the then opened discharge opening.

The operator therefore only needs to control the direction of rotation and, if necessary, the speed of the agitator and the closure of the dispensing opening in a suitable manner so that after the liquid mass has been poured in, the ice cream is quickly prepared with the optimum timing and freezing process and is then dispensed quickly and completely.

The disclosure content of EP 0 59S 221 A1 is hereby incorporated into the content of the present application by reference.

The aim of the present invention is to further improve the generic ice cream production machine. In particular, an excessive concentration of the ice cream mass in the upper area of the agitator should be avoided and

the mixing can be further improved.

To solve this problem, the features of the characterising part of patent claim 1 are provided.

According to the invention, the upper edges of the slats are connected to one another by circular connecting arches, unlike in the ice cream production machine according to EP 0 596 221 A1, whereby a more uniform flow is achieved in the upper area when the agitator rotates.

Advantageous further developments are characterized by claims 2 to 8.

The deflector according to claim 9 is particularly advantageous because it strips the ice mass that has risen up to the connecting arches or the circular ring from the ring and preferably conveys it downwards, which effectively prevents the ice mass from freezing to the connecting arches or the circular ring. Particularly advantageous embodiments of the deflector plate primarily intended for this purpose are characterized by claims 10 and 11.

It is also advantageous if, according to claims 12 to 18, an arm extends between the long legs of the L-shaped slats and the drive shaft tube. This significantly improves the stirring and mixing effect.

The twisting of the arm, which preferably consists of flat material, according to claims 16 to 18 is particularly advantageous because this causes the ice mass, which is moved on the arm with an upward component, to rotate in a direction opposite to the direction of rotation of the slats during normal operation.

It is particularly preferred if the deflector plate and the

Arm according to claims 19 and 20 are jointly attached to a substantially radially extending support arm.

The design according to claims 21 to 23 ensures that the ice mass is pressed downwards when it hits the deflector plate and is prevented from rising again by the flat support arm.

If necessary, the deflector plate could be omitted and the part of the flat support arm extending over the connecting arches or the circular ring could alone take over the ice mass deflection, whereby the part of the support arm extending over the connecting arches or the circular ring should be slightly inclined relative to the horizontal plane in such a way that above the connecting arches or the circular ring, in the area of the support arm 51 "a gap tapering in the working direction of rotation is created.

The invention is described below by way of example with reference to the drawing, in which:

Fig. 1 is a partially sectioned side view of an ice cream making machine according to the prior art,

Fig. 2 is a plan view of the object of Fig. 2 with the lid removed,

Fig. 3 is a front view of a cabinet in which the ice cream making machine is installed,

Fig. 4 is a perspective view of only the agitator of an ice cream production machine developed according to the present invention according to Figs. 1 to 3 and

Fig. 5 is a partially sectioned plan view of the article of Fig. 4.

According to Figs. 1 and 2, an ice cream production machine according to EP 0 596 221 A1 has a circular cylindrical insulating vessel 4, which has a circular cylindrical container 36 made of stainless steel sheet with a flat bottom wall 7 and a circular cylindrical peripheral wall 8 and an insulating foam 11 adjoining the bottom wall 7 and the peripheral wall 8 on the outside, which is preferably also surrounded on the outside by a closing casing.

Immediately behind the peripheral wall 8 or directly under the bottom wall 7, insulating foam 11 is poured around cooling coils 12, which cool the stainless steel sheet container 36 as evenly as possible without absorbing noticeable amounts of heat from the outside. The cooling coils 12 should preferably touch the sheet container 36 from the outside or below.

An agitator 5 is arranged inside the container 36, which consists of a central drive shaft tube 19 coaxial with the container 36 and essentially L-shaped slats 20 attached to its lower end, which have a bottom scraping edge 24 touching the bottom wall 7 and a wall scraping edge 25 interacting with the peripheral wall 8. While the bottom scraping edges 24 are continuous, there are interruptions 27 between the wall scraping edges 25, whereby the interruptions 27 of the three slats 20 shown in Figs. 1 and 2 are offset in the axial direction relative to one another in such a way that when the agitator 5 rotates completely, each area of the peripheral wall 8 that is radially aligned with the slats 20 has come into contact with a wall scraping edge 25 once.

As indicated in dash-dotted lines in Fig. 1 and 2, the drive shaft tube 19 surrounds a stationary standpipe 31 which is arranged in the area of the base 7 concentrically to the container 36, through the interior of which a preferably solid drive shaft 32 extends, also concentrically to the container 36, which is tightly guided through the base of the container 36 and is connected in a rotationally fixed manner to the output shaft of a reduction gear 34 arranged under the container 36. An electric motor 33 which can be driven in opposite directions of rotation at different speeds is flanged to the side of the reduction gear 34.

Between the upper end of the standpipe 31 and the drive shaft 32 and between the lower end of the standpipe 31 and the drive shaft tube 19_, an annular seal 35 or 35', for example in the form of a bush, is provided.

The upper end of the drive shaft 32 protrudes from the top of the standpipe 31 and is detachably connected to the drive shaft tube 19, for example by a fastening screw cap 21 in a manner not shown in detail. After unscrewing the screw cap 21, the drive shaft tube 19 with the slats 20 attached to it can be removed upwards from the container 3 6 for cleaning, repair or replacement and reinserted in the opposite direction and fastened.

To do this, it is only necessary to fold the preferably transparent lid 9 covering the top of the insulating vessel 4 upwards around the hinge 10 that holds it.

In the corner area between the bottom wall 7 and the peripheral wall 8 a removal opening 13 is provided according to Fig. 1, which is connected by an outlet pipe penetrating the insulating material 11.

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piece 14, the axis 26 of which forms an angle γ of 35° with the horizontal. The removal opening 13 is closed by a closure slide 15, which can also be seen in Fig. 3 and which sits flat and tightly on the outer end wall of the outlet pipe piece 14. The closure slide 15 can be pivoted about a pivot shaft 16, which can be seen in Fig. 3, by means of an operating handle 18 provided on it. The closure slide 15 slides on the outer end face of the outlet pipe piece 14 until it releases its removal opening 13.

In order to ensure that the locking slide 15 is pressed correctly into the closed position shown in Fig. 1 and 3, a locking head 37 fastened to a bolt can be provided on the side facing away from the pivot shaft 16, behind which a conically converging locking area 38 of the locking slide 15 slides when closing.

Below the removal opening 13 there is a slide 17, below which there is a receiving bowl 4 0 or another receiving element for the ice cream on a table-like plate 3 9 (Fig. 3).

According to Fig. 1 and 2, the upper ends of adjacent slats 20 are positively connected to one another by straight connecting rods 22. The connecting rods 22 engage the inner upper corners of the upwardly pointing legs of the L-shaped slats 20.

Since the upwardly pointing legs of the slats 20 are only attached to the drive shaft tube 19 at the bottom in the manner shown, there is a continuous gap 2 8 between the upwardly pointing legs of the slats 20 and the drive shaft tube 19 above the lower horizontal short legs. In the area of the radially inner

Particularly intensive mixing processes therefore occur right up to the top of the edge 29 of the upwardly pointing legs of the slats 20.

According to Fig. 1 and 2, the ice cream machine is installed in a piece of furniture 2 in such a way that the lid 9 can be opened from above and the locking slide 15 can be operated from the front by means of the operating handle 18. The drive unit 6 formed by the electric motor 33 and the reduction gear 34 can be driven in two different directions of rotation by means of a switch button 41 arranged on a front panel 3, namely in the working direction of rotation G (Fig. 2) and at an increased speed in the opposite direction of rotation H for the purpose of ejecting the finished product.

Relative to the axis of rotation 23, the slats 20 are attached to the drive shaft tube 19 in the manner shown in Fig. 1, tilted by an angle α of approximately 30° against the working direction of rotation G (Fig. 2).

According to Fig. 1 and 2, the upwardly pointing legs of the slats 20 are interlaced or twisted from bottom to top, in such a way that the angle ß defined by Fig. 2 between the horizontal section of the upright leg of the slats 20 from below, where it is preferably 90°, decreases upwards and according to Fig. 2 has decreased to approximately 60° in the upper area. In this way, when driven in the working direction of rotation G, a radially inward movement component is transferred to the ice cream mass.

The operation of the ice cream machine described is as follows:

·

First, the operator opens the lid 9, which is preferably connected to a contact for a safety switch that brings the machine to a standstill, by swinging it around the hinge 10 (Fig. 1), whereupon the liquid ice cream mixture is poured in from above in the desired amount. Due to the design according to the invention, the container 36 does not need to be completely filled. The ice cream machine 1 also works perfectly if the container 36 is only less than half full with liquid starting mixture.

The lid 9 is then closed again and by pressing the switch button 41 the agitator 5 is driven in the working direction of rotation G (Fig. 2) at a speed of 70 to 100 revolutions per minute (rpm).

As a result, the liquid mass will flow radially outwards and, due to the inventive design of the lamellae 20, also upwards along the peripheral wall 8. In the middle and upper area of the upright legs of the lamellae 20, the mass then receives a component of movement radially inwards, so that overall a flow in the direction of the dashed arrows in Fig. 1 is achieved. The liquid mass is thus guided in an optimal manner along the large surfaces of the cooled walls 7, 8, where it is scraped off as far as it freezes and is made to sink downwards again in the intermediate space 28. The movement of the liquid mass in the working direction of rotation G caused by the rotation of the agitator 5 is superimposed on the flow shown in dashed lines in Fig. 1.

During this process, the liquid mass becomes more and more dough-like until the ice cream is finally ready.

Now the operator places the bowl 4 0 under

the slide 17 (Fig. 3) and opens the locking slide by grasping the operating handle 18 and pivoting the locking slide anti-clockwise in Fig. 3.

The actuating button 41 for the electric motor 3 3 is then moved to the counter-rotation position, whereupon the agitator 5 is driven in the opposite direction of rotation at an increased speed of 150 to 200 rpm. The finished ice cream mass now has an opposite effect to that of the working direction of rotation G, in that a movement component is transferred to the ice cream mass radially outwards and downwards, while at the same time the centrifugal force is increased. In total, a force is thus exerted on the ice cream mass which moves it intensively in the direction of the discharge opening 13, where it exits and reaches the bowl 40 via the chute 17.

After the slats 20 have covered the entire bottom wall 7 and the entire peripheral wall 8, the ice cream mass is completely ejected through the discharge opening 13, to which the approximately doubled speed in the opposite direction H (Fig. 2) also contributes.

After the finished ice cream mixture has been completely ejected, the drive shaft tube 19 with the slats 20 and the connecting rods 22 can be removed from the container 36 for cleaning purposes by opening the lid 9 and unscrewing the screw cap 21. In this state, the interior of the container 36 can also be cleaned perfectly.

According to Fig. 4 and 5, the upper ends of the slats 20 are firmly connected to one another by part-circular connecting arches 22' instead of by connecting rods 22, which together form a circular ring 22". Preferably, the

The entire circular ring 22" is made from a single piece in the form of a sheet metal strip, the flat sides of which run parallel to the axis of rotation 23. The circular ring 22" is arranged concentrically to the axis of rotation 23 and is inserted into slots 42 extending axially downwards from the upper edges 43 of the slats 20 and is fastened there. The circular ring 22" projects slightly beyond the upper edges 43 of the slats 20 as shown in Fig. 4.

At any point on the circumference above the circular ring 22" a deflector 44 is provided, which has a deflector plate 45 that extends radially over the connecting arches 22', wherein the lower edge 46 of the deflector plate 45 is arranged at the smallest possible distance from the upper edge of the circular ring 22". If necessary, the lower edge 46 could also be in contact with the upper edge of the circular ring 22" and rub against it.

From the lower edge 46, the deflector plate 45 extends obliquely upwards, counter to the working direction of rotation G, so that the upper edge 47 of the deflector plate 45 is offset in the circumferential direction relative to the lower edge 46, counter to the working direction of rotation G.

In the area of the lower edge 46, the deflector plate 45 merges in one piece into a flat cover part 55 of a support arm 51, which is bent by less than 90° and is designed as a sheet metal part that extends perpendicular to the axis of rotation 23 or parallel to the plane of the circular ring 22" at the shortest possible distance from and, if necessary, touching the upper edge of the circular ring 22". Radially on the outside, the flat cover part 55 merges via an upwardly directed step 53 into a fastening tab 54 which again runs radially outwards and which has a fastening hole 52 at its radially outer end, by means of which the support arm 51 can be suitably attached, for example, to the support arm 51 as shown in Fig. 5.

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The cover part extends radially inwards over the free space between the slats 20 and the drive shaft tube 19. An arm 48 made of strip-shaped material is bent vertically downwards from its radially inner end. The arm 48 is preferably a rigid sheet metal strip, the upper edge 50 of which merges in one piece into the horizontal flat cover part 55.

The lower edge 49 of the arm 48 extends approximately to the short horizontal base bar 20' of the slats 20 and ends just above it.

As can be seen particularly clearly from Fig. 4, the arm 48 is twisted in such a way that the lower edge 49 is rotated 180° anti-clockwise relative to the upper edge 50 of the arm 48 - viewed from below. In this way, the arm 48 takes on a screw-like shape with a very large pitch (only half a turn over the entire length).

According to Fig. 5, the circular ring 22" has a clear but small distance A from the peripheral wall 8 of the insulating vessel 4. This is brought about by the fastening slots 42 being located radially within the interruptions 27 of the lamellae 20.

The operation of the described further development according to the present invention is as follows:

The support arm 51 with the deflector plate 45 and the arm 48 together form a deflector 44 which has both a deflection and a mixing function.

When the agitator 5 rotates in the working direction G

the more or less viscous ice mass moves axially upwards and outwards due to the shape of the slats 20 and tends to freeze in the upper area of the insulating vessel 4 on the peripheral wall 8 and in the area of the circular ring 22". Due to the movement component in the working direction of rotation G, the ice mass will repeatedly run into the work plate 45, which, due to its inclination, gives the ice mass a movement component axially downwards, so that it is stripped off the two flat sides of the connecting arches 22' and from the upper area of the peripheral wall 8 and conveyed downwards. In this way, freezing and excessive accumulation of ice mass in the upper area of the insulating vessel 4 are effectively avoided. The deflector plate advantageously extends radially outwards to over the upper edge of the peripheral wall 8 and radially inwards to over the space between the slats 20 and the drive shaft tube 19.

During its circulation in the insulating vessel 4, which is forced by the slats 20, the ice mass also repeatedly hits the arm 48 which is in the way and is thereby forced to move past the arm 48, which leads to better mixing. Due to the twisting of the arm 48, the ice mass also has a tendency to rotate against the working direction of rotation G as it rises, which also significantly promotes the mixing of the ice mass.

The fastening means 56 (Fig. 5) which fix the support arm 51 to the insulating vessel 4 by means of the fastening hole 52 can be designed in such a way that the support arm 51 with the deflector plate 45 and the mixing arm 48 can be easily dismantled, which is useful for the purpose of intensive cleaning.

S/Sv-C 4558

List of reference symbols

1 ice cream making machine

2 Furniture

3 Front panel

4 Insulated vessel

5 Agitator

6 Drive unit

7 Floor wall

8 Perimeter wall

9 Lid

10 Hinge

11 Foaming

12 Cooling coil

13 Removal opening

14 Outlet agitator

15 locking slide

16 Swivel shaft

17 Slide

18 Operating handle

19 Drive shaft tube

20 Stirring tool (lamella)

21 Fastening screw cap

22 connecting rod 22' connecting bend 22" circular ring

23 Rotation axis

24 Floor scraping edge

25 Wall scraper edge

26 Axis of the removal opening

27 Interruption

28 Space

·

29 Inner edge 30 Corner 31 Standpipe 32 drive shaft 33 engine 34 transmission 35 Ring seal 36 Stainless steel container 37 Bolt head 38 Closure area 39 plate 40 Bowl 41 Switch button 42 slot 43 Top edge 44 Deflector 45 Deflector plate 46 lower edge of the deflector plate 47 upper edge of the deflector plate 48 poor 49 lower edge of the arm 4 8 50 upper edge of the arm 48 51 Beam 52 Mounting hole 53 Level 54 Mounting bracket' 55 Cover part 56 Fasteners

Claims (24)

S/SV-C 4558 Protection claims Ice cream making machine with an insulated vessel (4) which is open at the top and can preferably be closed by a lid (9), which has insulation (11) on the outside and a container (3 6) on the inside, which is preferably made of stainless steel, behind or in the walls (7, 8) of which cooling coils (12) are provided and in which a stirring mechanism (5) carrying stirring tools (20) is arranged concentrically with an axis of rotation (23) coinciding with the axis of rotation of the container, which can be driven from below by a drive unit (6) to perform a rotational movement, wherein in the corner area between the "flat bottom wall (7) and the circular cylindrical peripheral wall (8) there is provided a removal opening (13) which can be selectively closed or opened by a closure member (15) which can be actuated from the outside, wherein the stirring mechanism (5) can be driven by the drive unit (6) in opposite directions of rotation (G, H), wherein the drive shaft (19, 32) is preferably mounted independently of the lid (9) and in particular only in the area of the bottom wall (7) and wherein the stirring tools are essentially L-shaped lamellae (20) in scraping engagement with the bottom and peripheral wall (7, 8), which are arranged and designed in such a way that when the stirring mechanism (5) is driven in the working direction of rotation (G) of the liquid or dough-like mass in the container (36) they impart a movement component radially outwards at the bottom and then axially upwards as well as a movement component radially inwards at the top and wherein when the stirring mechanism (5) is driven in the opposite direction of rotation (H) of the liquid or dough-like mass in the container I* (36) a movement component radially outwards and axially downwards, characterized in that that the adjacent upwardly pointing legs of the slats (20) are connected at the top by part-circular connecting arches (22') concentric with the axis of rotation (23). 2. Machine according to claim 1, characterized in that the connecting arches (22·) are integrated into a uniform, closed circular ring (22") concentric with the axis of rotation (23). 3. Machine according to claim 1 or 2, characterized in that the connecting arches ( ^22f ) or the circular ring (22") are formed from upright strip material, in particular sheet metal strips. 4. Machine according to claim 1 or 2, characterized in that the connecting arches (22') or the circular ring (22") are inserted from above into slots (42) in the upper edges (43) of the slats (20) and are fastened there. 5. Machine according to claim 4, characterized in that the connecting arches (22') or the circular ring (22") protrude slightly from the top of the upper edges (43) of the slats (20). 6. Machine according to one of the preceding claims, characterized in that the connecting arches (22') or the circular ring (22") are at a small distance from the peripheral wall (3). 7. Machine according to one of the preceding claims, characterized in that the slats (20) are laterally have a scraping edge (25) provided with interruptions (27) and the connecting arches (22') or the circular ring (22") are attached radially inside the interruptions (27) to the slats (20). 8. Machine according to claim 6 or 7, characterized in that the distance of the connecting arches (22·) or the circular ring (22") from the peripheral wall (8) is 10 to 20 mm and in particular about 15 mm. 9. Machine according to one of the preceding claims, characterized in that a deflector (44) is provided above the connecting arches (22') or the circular ring (22") and preferably at the shortest distance above them. 10. Machine according to claim 9, characterized in that the deflector (44) has a deflector plate (45) which preferably projects upwards from the connecting arches (21'), which extends essentially radially over the connecting arches (22') or the circular ring (22") and in particular ends above the peripheral wall (8) of the insulating vessel (4). 11. Machine according to claim 10, characterized in that the deflector plate (45) is inclined relative to the vertical, in such a way that, viewed in the working direction (G), the lower edge (46) is spaced from a vertical radial plane running through the upper edge (47) in the circumferential direction, the angle of the deflector plate (45) to a vertical radial plane is preferably 20 - 40° and in particular approximately 30°. 12. Machine according to one of claims 9 to 11, characterized in that the deflector (44) has a at least at least substantially vertically extending arm (48) from above into the space between the L-shaped slats (20) and the central drive shaft tube (19). 13. Machine according to claim 12, characterized in that the arm (48) extends approximately to the base web (20') of the stirring tools (20). 14. Machine according to claim 12 or 13, characterized in that the arm (48) consists of strip material, in particular a rigid sheet metal strip. 15. Machine according to claim 14, characterized in that the flat sides of the strip material run substantially perpendicular to the radial direction. 16. Machine according to claim 14 or 15, characterized in that the strip material is twisted. 17. Machine according to claim 16, characterized in that the strip material is twisted in such a way that the lower edge (49) is rotated relative to the upper edge (50) of the arm by 180° with respect to the longitudinal direction of the arm (48). 18. Machine according to claim 16 or 17, characterized in that the lower edge (49) is rotated relative to the upper edge (50) according to the working direction of rotation (G). 19. Machine according to one of claims 1 to 11 and 12 to 18, characterized in that the deflector plate (45) and the arm (48) are attached to a common, at least substantially radial support arm (51). - 5 20. Machine according to claim 19, characterized in that the deflector plate (45), the arm (48) and the support arm (51) are formed in one piece. 21. Machine according to one of claims 9 to 20, characterized in that the support arm (51) also consists of strip-shaped material, in particular a sheet metal strip, at least in the area where it extends over the connecting arches or the circular ring. 22. Machine according to claim 21, characterized in that the deflector plate (45) is formed on the edge of the part of the support arm (51) opposite the working direction of rotation (G) which extends radially over the connecting arches (22') or the circular ring (22"). 23. Machine according to one of claims 19 to 22, characterized in that the support arm (51) extends radially outward beyond the peripheral wall (8) and is fastened there to the insulating vessel (4) by fastening means (52, 56). 24. Machine according to one of claims 19 to 23, characterized in that the support arm (51) has an upwardly projecting step (53) radially outside the connecting arches (22') or the circular ring (22") and preferably above the peripheral wall (8) or radially outside thereof, and that the step is followed by a radially outwardly extending fastening tab (54) on which the fastening means (52) are provided.