Ice cream freezer

Abstract

An ice cream freezer comprising an elongated housing with a jacket and an inner space in which an agitator (30) with a rotatable hollow cylinder (31) is arranged, said cylinder (31) comprising a scraper (50) arranged along the periphery of the cylinder (31), an inlet (60) in front of said scraper (50) for enabling an ice cream mix (M) to enter the interior of said cylinder (31) and an outlet (62) behind said scraper (50) for enabling the ice cream mix (M) to leave the interior (32) of said cylinder (31), wherein said inlet (60) comprises a guiding surface (67) having a guiding angle (θ) of at least 3° for pushing the ice cream mix (M) in the axial direction (D) of said cylinder (31).

Description

Technical Field

[0001] This invention relates to an ice cream freezer with an elongated shell in which a stirrer is disposed. The stirrer has a hollow cylinder for stirring and mixing an ice cream mixture. A scraper is disposed around the periphery of the cylinder, with an ice cream mixture inlet located before the scraper and an ice cream mixture outlet located after the scraper, so that the ice cream mixture can enter and exit the cylinder separately. This invention also relates to a system and method for producing ice cream using this type of ice cream freezer. Background Technology

[0002] Currently, many food processing devices are used in the food processing industry to produce ice cream products, including dairy-based ice cream products and water-based frozen snacks such as popsicles. Frozen custard, frozen yogurt, fruit sorbet, gelato, and frozen dairy desserts are some product names used to distinguish different types and styles of ice cream products.

[0003] In the large-scale production of ice cream products, an ice cream mixture is prepared to be processed into ice cream products. The mixture is typically pumped through a continuous freezer with two main functions. The first function is to agitate a controlled amount of air into the mixture, and the second function is to freeze most of the water in the mixture into a large number of small ice crystals.

[0004] Continuous freezing machines typically take the form of a sleeved cylindrical shell housing rotating blades, an agitator, and sometimes a churn. During production, the ice cream mixture is metered into the shell, for example, using a gear pump. Simultaneously, a constant airflow is introduced into the shell and churned into the mixture by the rotating agitator located within the sleeved shell. This agitator then effectively functions as both a mixer and a stirrer for the ice cream mixture. Refrigerant passing through the sleeve surrounding the shell freezes the ice cream mixture fed into the freezing machine, forming ice crystals within the mixture. The ice cream mixture is then used to form the finished ice cream product.

[0005] Also known as a scraper, blades are arranged on a rotating agitator, causing the frozen mixture to be continuously scraped off the inner shell walls. The agitator churns the product within. A controlled amount of air is fed into the freezer, either alone or with the ice cream mixture. The rotation of the agitator ensures that the air is evenly incorporated into the mixture, resulting in a homogeneous ice cream mixture. If the agitator is used in a freezer, it subjectes the mixture to a churning action, thereby enhancing the incorporation of air into the ice cream mixture.

[0006] Air incorporation into the ice cream mixture increases its volume. Typically, 0.8 to 1 liter of air is introduced per liter of ice cream mixture. Depending on the type of ice cream product, the mixture typically leaves the freezer at a temperature of -8°C to -3°C, where, depending on the composition, 30% to 55% of the water in the mixture may freeze into ice crystals.

[0007] To convey the ice cream mixture through the freezer, a pump is typically used to drive the mixture forward from the continuous freezer, for example, to a feeder, ice cream forming unit, or filling machine. Depending on the configuration, the pump may optionally or additionally be located upstream of the freezer to feed the mixture into the freezer. As the mixture gradually decreases in temperature as it passes through the freezer, its viscosity increases, and more energy is required to convey the mixture through the freezer.

[0008] Examples of ice cream freezers can be found in patent documents EP1178734B1 and US4162127A.

[0009] While continuous ice cream freezers successfully freeze ice cream mixtures, limitations remain regarding how low the temperature of the mixture passing through the freezer can go. This is especially true for low-fat ice cream products such as sorbets and water ice, where viscosity increases rapidly with decreasing temperature. The high viscosity of these products makes it challenging to provide sufficient pumping power through the freezer to ensure adequate discharge pressure to the discharge pump. Conversely, even if ice cream mixtures with lower water content do not experience the same rapid increase in viscosity, a relatively large amount of energy is still required to transport the mixture through the freezer. Summary of the Invention

[0010] One object of the present invention is to overcome, at least in part, one or more limitations of the prior art. In particular, an object of the present invention is to provide an ice cream freezer through which ice cream mixtures are fed more easily, for example to save energy and / or to ensure adequate discharge from the freezer.

[0011] In a first aspect of the invention, this is achieved by an ice cream freezer comprising an elongated outer shell having a sheath and an internal space, and a stirrer comprising a hollow cylinder arranged in the internal space and rotating about a central axis of the cylinder in a direction of rotation to stir and mix an ice cream mixture fed through the internal space. The cylinder includes a scraper arranged along its periphery; an inlet located ahead of the scraper in the direction of rotation for allowing the ice cream mixture to enter the cylinder; and an outlet located behind the scraper in the direction of rotation for allowing the ice cream mixture to exit the cylinder. The inlet includes a guide surface having a guide angle of at least 3° to push the ice cream mixture in the axial direction of the cylinder.

[0012] Using a cylinder inlet with a sloping guide surface is advantageous because it facilitates the continuous forward propulsion of the ice cream mixture. Clearly, the ice cream mixture is propelled from the inlet to the outlet of the ice cream mixture in the outer shell. Therefore, in addition to stirring and mixing, the agitator also acts as a pumping device for the ice cream mixture. This helps ensure sufficient discharge capacity from the freezer. In many cases, the sloping guide surface also helps save on the total energy required to feed the ice cream mixture through the ice cream freezer.

[0013] Other objectives, features, aspects, and advantages of the ice cream freezer will become apparent from the following detailed description and accompanying drawings.

[0014] In a second aspect of the invention, the above objective is also achieved by an ice cream production system comprising an ice cream freezer for producing ice cream blocks; an ice cream forming apparatus configured to form ice cream blocks into individual ice cream blocks; a freezing apparatus configured to receive the individual ice cream blocks and lower their temperature; and a packaging machine configured to wrap packaging material around the individual ice cream blocks, wherein the ice cream freezer is the ice cream freezer according to the first aspect.

[0015] In a third aspect of the invention, the above objective is also achieved by a method for producing ice cream, the method comprising producing ice cream blocks, shaping the ice cream blocks into individual ice cream blocks, lowering the temperature of the individual ice cream blocks, and wrapping packaging material around each individual ice cream block, wherein the production of the ice cream blocks comprises using an ice cream freezer according to the first aspect. Attached Figure Description

[0016] Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, wherein...

[0017] Figure 1 This is a schematic diagram of an ice cream freezer.

[0018] Figure 2 yes Figure 1 A 3D view of the agitator in an ice cream freezer.

[0019] Figure 3 yes Figure 2 Front view of the stirrer shown.

[0020] Figure 4 yes Figure 2 The side view of the stirrer shown is shown.

[0021] Figure 5 yes Figure 2 A partial front view of the stirrer shown.

[0022] Figure 6 yes Figure 2A partial 3D view of the stirrer shown.

[0023] Figure 7 yes Figure 2 A schematic cross-sectional side view of the agitator shown.

[0024] Figure 8 yes Figure 2 The schematic cross-sectional side view of the stirrer shown corresponds to Figure 7 However, the view from the opposite side,

[0025] Figure 9 It is used for Figure 1 A perspective view of another embodiment of the agitator in an ice cream freezer.

[0026] Figure 10 yes Figure 9 The front view of the stirrer shown.

[0027] Figure 11 This is a schematic diagram of an ice cream production system, and

[0028] Figure 12 This is a flowchart of the ice cream manufacturing process. Detailed Implementation

[0029] refer to Figures 1 to 4 The illustration shows an ice cream freezer 1. The ice cream freezer 1 has an elongated outer shell 2, which has a sheath 3 and a cylindrical internal space 4. A stirrer 30 is arranged in the internal space 4 and has a hollow cylinder 31, which is mounted to rotate about the central axis A1 of the cylinder 31 in the direction of rotation R. The cylinder 31 has an outer peripheral surface 34 and an inner surface 33, see [reference needed]. Figure 7 The distance between these surfaces 34, 33 defines the thickness t of the hollow cylinder 31. This thickness can be, for example, 5 mm to 15 mm. The outer shell 2 has a first inlet 11 and a first outlet 12, which are arranged for feeding the ice cream mixture M through the internal space 4. The outer shell 2 has a second inlet 21 and a second outlet 22, which are arranged for feeding a cooling fluid CF, i.e., a refrigerant, through the sheath 3, thereby cooling the ice cream mixture M fed through the internal space 4. The agitator and all its components can be made of stainless steel.

[0030] A motor (not shown) is connected to the shaft 15 of the mixer 30 for rotating the mixer 30. As the mixer rotates, the drum 31 also rotates in the direction of rotation R. When this occurs, the ice cream mixture M fed through the internal space 4 is agitated and mixed. The drum 31 has a scraper 50 mounted along its periphery for scraping the ice cream mixture off the inner wall 5 of the outer shell 2. The tip of the scraper 50 is positioned at the foremost point in the direction of rotation R.

[0031] refer to Figure 5 and 6 The cylinder 31 has an inlet 60, which, when viewed in the direction of rotation R, is located before the scraper 50. This allows the ice cream mixture M to be pushed into the interior 32 of the hollow cylinder 31 as it rotates. The cylinder 31 has an outlet 62, which, when viewed in the direction of rotation R, is located after the scraper 50. This is used to discharge the ice cream mixture M from the interior 32 of the cylinder 31 as it rotates. In this way, the ice cream mixture M can continuously enter and exit the interior 32 of the cylinder 31.

[0032] The inlet 60 has a guide surface 67 having a guide angle θ of at least 3°. The guide surface 67 pushes the ice cream mixture M in the axial direction D of the cylinder 31. This effectively pushes the ice cream mixture M in the direction from the first inlet 11 to the first outlet 12, which is arranged to feed the ice cream mixture M through the internal space 4 of the outer shell 2.

[0033] The guide angle θ can be at least 5°, at least 8°, at least 15°, or even at least 30°. When the guide angle θ is at least 3°, 5°, 8°, or 15°, it can be less than 25°, i.e., the upper limit is 25°. The guide angle θ is referenced to a line perpendicular to the axis A1 of the cylinder 31 and is the supplementary angle of the helix angle of the axis A1 of the cylinder 31. The guide surface 67 can be slightly concave or slightly convex, in which case the guide angle θ is calculated as the average guide angle of the curvature forming the guide surface 67. The inlet 60 can have a surface 61 opposite to the guide surface 67 and inclined at the same angle as the guide angle θ of the guide surface 67.

[0034] An inlet 60 and an outlet 62 can be formed in the cylinder 31 with an opening 91, and a scraper 50 can be positioned above the opening 91 to divide the opening 91 into an inlet 60 and an outlet 62. This is advantageous from a manufacturing point of view, allowing the inlet 60 and outlet 62 to be formed in a single operation, with the scraper 50 separating the inlet 60 from the outlet 62. Another advantage of the opening 91 is that the ice cream mixture can more easily flow into and out of the interior 32 of the cylinder 31 through the inlet 60 and outlet 62.

[0035] The guide surface 67 can extend from the inlet 60 to the outlet 62. This is advantageous because the outlet 62 also includes the guide surface 67, further enhancing the pumping effect of the agitator 30. The outlet 62 may also have a surface that is opposite to the guide surface 67 and inclined at the same angle as the guide angle θ of the guide surface 67.

[0036] Further reference Figure 7 and 8The inlet 60 may include an inlet surface 64, the top of which is chamfered or tilted at an angle β of at least 10°. In the example shown, the inlet surface 64 is chamfered. The angle β of the chamfer (inlet chamfer) is measured relative to the radial direction of the cylinder 31 at a position 71 where the chamfer begins on the outer peripheral surface 34 of the cylinder 31. Figure 7 As shown. The chamfer extends inward along the direction toward the inner surface 33 of the hollow cylinder 31. The chamfer may have an angle β of at least 20°, at least 40°, or at least 60°.

[0037] The inlet surface 64 may be top-beveled at at least 30% of the thickness t of the cylinder 31. The inlet surface 64 may be top-beveled at at least 30%, at least 40%, at least 50%, at least 60%, or at least 80% of the thickness t of the cylinder 31. It may even be top-beveled at 100% of the thickness t of the cylinder 31, in which case it is beveled.

[0038] The chamfered inlet surface 64 has the advantage that ice cream chunks are easier to push into the interior 32 of the cone 31, requiring less energy to rotate the mixer 30. Additionally, the mixing efficiency of the mixer 30 is increased.

[0039] The outlet 62 of the cylinder 31 may include an outlet surface 65, the top of which is chamfered or tilted at an angle β of at least 10°. In the example shown, the outlet surface 65 is chamfered. The angle β of the outlet chamfer is measured relative to the radial direction of the cylinder 31 at a position 72 where the outlet chamfer begins on the outer peripheral surface 34 of the cylinder 31. Figure 7 As shown. The outlet chamfer extends inward along the direction toward the inner surface 33 of the hollow cylinder 31. The outlet chamfer may have an angle β of at least 20°, at least 40°, or at least 60°.

[0040] The outlet surface 65 may be chamfered at the top of at least 30% of the thickness t of the cylinder 31. The outlet surface 65 may be chamfered at the top of at least 30%, at least 40%, at least 50%, at least 60%, or at least 80% of the thickness t of the cylinder 31. It may even be chamfered at the top of 100% of the thickness t of the cylinder 31, in which case it is beveled.

[0041] The chamfered outlet surface 65 has the advantage that ice cream chunks flow more easily from the interior 32 of the drum 31, requiring less energy to rotate the mixer 30. Furthermore, the mixing efficiency of the mixer 30 is increased.

[0042] The inlet chamfer and outlet chamfer can be chamfered or angled at the same angle or bevel. This is advantageous from a manufacturing point of view and also improves the flow of ice cream mixture into and out of the cylinder 31.

[0043] The cylinder 31 may have a protrusion 63 extending above the outlet 62. For example... Figure 7 As can be seen, the scraper 50 can be attached to the end 81 of the protrusion 63. The scraper attachment point is then located above the hole 91. The protrusion 63 can extend from the outlet surface 65 and divide the outlet 62 into two outlet surface portions 65 and 66.

[0044] The protrusion 63 may include an inner surface 82 facing the center C of the cylinder 31. This inner surface 82 may be inclined at an angle α of at least 10° relative to the tangential direction T of the cylinder 31. The tangential direction T is defined by a point 70 on the cylinder 31, which is radially aligned along axis A2 with the end 81 of the protrusion 63. Figure 7 As shown.

[0045] Back Figure 5 Hole 91 can be one of a series of similar holes 91, 92 arranged in the cylinder 31. Holes 91, 92 extend in the axial direction D of the cylinder 31 and are separated by rib 93. Scraper 50 extends on rib 93. Figure 6 As shown in the optimal configuration, each rib 93 has a respective outer surface 94 that is chamfered or inclined at least 3 mm in the axial direction D of the cylinder 31, forming a chamfer 69 in the rib 93. The chamfer 69 in the rib 93 is located where the scraper 50 extends on the rib 93. The chamfer 69 may extend over at least 75% of the width of the rib 93, or even over the entire width of the rib 93. The width of the rib 93 extends in the axial direction D of the cylinder 31. The width of the rib may be, for example, 10 mm to 20 mm. The chamfer 69 in the rib 93 provides easier cleaning and improves the flow of the ice cream mixture M, particularly from the outlet 62.

[0046] One or more of the ribs 93 may include a guide surface 67 of the inlet 60 of the cylinder 31. Then the outer surface 94 of the rib 93 is preferably chamfered or beveled on the surface 61 of the respective rib 93 that includes the guide surface 67 in the rib 93.

[0047] In addition to the rib 93 described herein, the cylinder 31 may include ribs of other forms and shapes. The same applies to the holes 91, 92 formed by the inlet 60 and outlet 62 of the cylinder 31, i.e., the cylinder 31 may include inlets and outlets of other shapes and types. Figure 9 and 10 Another example of a mixer 130 is shown. For this mixer 130, the cylinder 131 has holes 191, 192 and ribs 193 of different shapes, wherein the inclined guide surface 167 helps to push the ice cream mixture in the axial direction.

[0048] refer to Figure 11The illustration shows an ice cream production system 700. In short, an ice cream mixture M can be produced using an ice cream freezer 702 by using cream, sugar, and other ingredients. The ice cream freezer 702 is advantageously the ice cream freezer 1 as described above. The ice cream mixture M can then be formed into individual ice cream blocks 705 in an ice cream forming device 704. This can be done in different ways, for example, by extrusion or molding. An optional stick handling device 706 can place ice cream sticks into the individual ice cream blocks 705.

[0049] After the sticks are provided, individual blocks 705 can be placed in a freezing device 707, such as a freezing tunnel. Finally, in a packaging machine 708, the individual blocks 705 can be wrapped in packaging material 710 to form an ice cream product ready for shipment. The ice cream forming device 704, the stick handling device 706, the freezing device 707, and the packaging machine 708 are typical commercially available equipment suitable for ice cream production.

[0050] refer to Figure 12 The diagram illustrates a method 800 for producing ice cream. Method 800 includes producing ice cream blocks 802, shaping the ice cream blocks 804 into individual ice cream blocks, lowering the temperature of the individual ice cream blocks 807, and wrapping each individual ice cream block 705 with packaging material 808 710. The production 802 of the ice cream blocks 304 includes using an ice cream freezer 1 as described above. Optionally, ice cream sticks 806 are processed by inserting sticks into the individual ice cream blocks.

[0051] As can be seen from the above description, although various embodiments of the present invention have been described and shown, the present invention is not limited thereto, but may be implemented in other ways within the scope of the subject matter defined by the appended claims.

Claims

1. An ice cream freezer comprising: an elongated housing (2) having a jacket (3) and an interior space (4), and an agitator (30) comprising a hollow barrel (31) disposed in the interior space (4) to rotate about a central axis (Al) of the barrel (31) in a rotational direction (R) to agitate and mix an ice cream mix (M) fed through the interior space (4), the barrel (31) comprising: a scraper (50) disposed along a periphery of the barrel (31), an inlet (60) located before the scraper (50) as seen in the rotational direction (R) to enable the ice cream mix (M) to enter an interior (32) of the barrel (31), and an outlet (62) located after the scraper (50) as seen in the rotational direction (R) to enable the ice cream mix (M) to exit the interior (32) of the barrel (31), wherein the inlet (60) comprises a guide surface (67) having a guide angle (Q) of at least 3° to push the ice cream mix (M) in an axial direction (D) of the barrel (31), the guide angle (Q) being referenced to a line perpendicular to the central axis of the barrel (31).

2. An ice cream freezer as claimed in claim 1 wherein, the inlet (60) and the outlet (62) form a bore (91) within the barrel (31), the scraper (50) being disposed above the bore (91) to divide the bore (91) into the inlet (60) and the outlet (62).

3. An ice cream freezer as claimed in claim 1 or 2 wherein, the guide surface (67) extends from the inlet (60) to the outlet (62) such that the outlet (62) also comprises the guide surface (67).

4. Ice cream freezer according to the preceding claim 1 or 2, wherein, the inlet (60) comprises an inlet surface (64) that is either top chamfered or top inclined by an angle (b) of at least 10°.

5. An ice cream freezer as claimed in claim 4 wherein, the inlet surface (64) is top chamfered over at least 30% of a thickness (t) of the barrel (31).

6. Ice cream freezer according to the preceding claim 1 or 2, wherein the outlet (62) comprises an outlet surface (65) that is either top chamfered or top inclined by an angle (b) of at least 10°.

7. An ice cream freezer as claimed in claim 6 wherein, the outlet surface (65) is top chamfered over at least 30% of the thickness (t) of the barrel (31).

8. Ice cream freezer according to the preceding claim 1 or 2, wherein, the barrel (31) comprises a protrusion (63) extending above the outlet (62) and the scraper (50) is attached to an end (81) of the protrusion (63).

9. The ice cream freezer of claim 6 wherein, the protrusion (63) extends from the outlet surface (65) and divides the outlet (62) into two outlet portions.

10. The ice cream freezer of claim 8 wherein, the protrusion (63) comprises an inner surface (82) that is inclined towards a center (C) of the barrel (31) by an angle (a) of at least 10° relative to a tangential direction (T) of the barrel (31) defined by a point (70) on the barrel (31) radially aligned with the end (81) of the protrusion (63).

11. Ice cream freezer according to the preceding claim 1 or 2, wherein the inlet (60) comprises a surface (61) opposite the guide surface (67) and inclined by the same angle (Q) as the guide angle (Q) of the guide surface (67).

12. The ice cream freezer of claim 2 wherein, Said hole (91) is one of a series of similar holes (91, 92) arranged in said cylinder (31), said holes (91, 92) extending along said axial direction (D) of said cylinder (31) and being separated by a rib (93) on which said doctor blade (50) extends, said rib (93) comprising an outer surface (94) which is chamfered or bevelled by at least 3 mm along said axial direction (D) of said cylinder (31) in the position where said doctor blade (50) extends on the rib (93).

13. An ice cream freezer as claimed in claim 12 wherein, Said rib (93) comprises said guiding surface (67) of the inlet (60) of said cylinder (31), an outer surface (94) of said rib (93) being chamfered or bevelled on a surface (61) of the rib (93) opposite said guiding surface (67) comprised in said rib (93).

14. An ice cream production system (700) comprising: an ice cream freezer for producing an ice cream mix (M), an ice cream forming device (704) for forming said ice cream mix (M) into individual ice cream pieces (705), a freezing device (707) for receiving said individual ice cream pieces (705) and lowering their temperature, a packaging machine (708) for wrapping a packaging material (710) around individual ice cream pieces (705), characterized in that said ice cream freezer is according to any of the preceding claims 1 to 13.

15. A method (800) for producing ice cream, comprising: producing ice cream pieces, forming said ice cream pieces into individual ice cream pieces (705), lowering the temperature of said individual ice cream pieces (705), wrapping a packaging material (710) around individual ice cream pieces (705), characterized in that said producing of ice cream pieces comprises using an ice cream freezer according to any of the claims 1 to 13.

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