JPH0151982B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an ice cream making machine, particularly an ice cream making machine for home use.

[Conventional technology and problems]

As has long been known, in the production of ice cream it is necessary to stir an ice cream mixture while it is frozen. If this is omitted, large ice crystals will form and the product will become unpalatable. Early versions of home ice cream machines used an external container with a rotating inner container to provide stirring. The space between the two containers is filled to the brim with a mixture of ice and salt, and the ice cream mixture is placed in an inner container which is rotated and the ice cream mixture is agitated by the stationary mixing impeller. Alternatively, the mixing vane may be rotated. Ice cream machines of this type are currently in use, and although in earlier versions rotation could be carried out by hand, it is now usually done by electric motors. Although effective, such ice cream machines are relatively cumbersome and inconvenient to use because they require the preparation of a mixture of crushed ice and salt.

Another form of domestic ice cream making machine is essentially a small freezer, the equipment being equipped with a refrigerator and a device for stirring the ice cream mixture in the container. Although such ice cream machines are very effective, they are expensive due to the need to install ice storage equipment.

A third type of device is commercially available, consisting solely of a container containing rotating mixing vanes that are driven by a small electric motor connected to a current-carrying line by a connecting cord. Such an ice cream making machine is simply placed in the freezer compartment of an ordinary refrigerator, and a connecting cord is led out of the refrigerator through the seal on the door and connected to a power line. Agitation is carried out until the ice cream mixture reaches the desired consistency. This type of ice cream making machine is equipped with a thermostatic adjustment device which shuts off the motor when the ice cream mixture reaches a consistency that causes the motor to overheat and trigger a thermostat switch.
In some ice cream machines of this type, the ice cream mixture is placed in a simple metal container and the ice cream mixture is simply cooled in a freezer compartment. However, in some types of apparatus, an electric motor is used not only to rotate the mixing vanes in the ice cream mixture container, but also to move a small fan that acts to draw air into the bottom and upper sides of the container. is also used. This certainly speeds up the freezing of the ice cream mixture to some extent.

Although this last type of home ice cream machine is very effective and inexpensive, it is not widely available. This is believed to be due to the user's irrational fear of putting an electrical device connected to the refrigerator into the refrigerator. This is also despite the fact that in some cases the voltage applied to the motor is only 24 volts.

One object of the invention is to provide a home ice cream machine according to a third mode, which eliminates the use of a connection to a power supply by installing a battery pack as part of the ice cream machine. While this concept is certainly simple, it has proven extremely difficult in practice to construct an ice cream machine capable of producing ice cream with a battery pack of acceptable size.
After considerable experimentation, it has been determined that the solution to this problem lies in the installation of a fan that blows cold air from the refrigerator compartment directly into the ice cream mixture while it is being stirred. It has been found that by doing so it is possible to produce ice cream of acceptable consistency during the life of a pack of six commercially available rechargeable batteries.

Another object of the invention is that the time required to make ice cream is reduced and that the quality of the product is slightly better regardless of whether the device is powered by pack-mounted batteries or by a power connection. The present invention provides a home ice cream making machine according to a third mode that exhibits improved effects. These improvements are accomplished through the use of fans or other devices that blow cold air from the freezer directly onto the ice cream. In this regard, it has also been found that the use of two fans side by side rather than the use of just one fan results in even greater improvements.

The present invention comprises a container in the form of an annular trough, a mixing blade disposed within the trough member so as to be rotatable around its axis, and an electric motor device drivingly connected to the blade to rotate the blade. The present invention relates to a refrigerator-insertable household ice cream making machine, characterized in that it is equipped with a device for forming a downward air flow that blows onto the surface of the ice cream mixture inside the refrigerator.

In a preferred embodiment of the invention, the electric motor for driving the mixing vanes and fan is powered by a battery located in the pack, so that the ice cream maker can be installed inside the refrigerator without having to run a power cord into the refrigerator. This is a self-contained device that can be placed inside a refrigerator. Additionally, a pair of juxtaposed fans are preferably used to direct the air over the surface of the ice cream in the container, and the cooling air from the fans serves to pull the ice cream mixture away from the inner and outer walls of the container as the blades rotate. Preferably, a mixing vane is used which is shaped in such a way that a gap is formed between the ice cream mixture and the container wall, allowing contact of the ice cream mixture.

For a better understanding and implementation of the features of the present invention, preferred embodiments will be described below with reference to the accompanying drawings.

〔Example〕

The illustrated ice cream machine is housed in a plastic container consisting of a lower part 10 and an upper part 11 interconnected by a bayonet joint, shown in cross section at 12. lower part 10
A handle portion 10a extends from the upper portion 11 and a similar handle portion 11a extends from the upper portion 11. These parts form a handle that is used to move the ice cream machine into and out of the freezer compartment of the refrigerator.

Inside the lower part 10 is a container 13 in which ice cream is made. It takes the form of an annular trough of stainless steel or other metal with an open top. A mixing blade 14 having a structure described in detail below is mounted inside the container 13 so as to be rotatable about the axis of the container by a drive shaft 15. All other parts of the ice cream machine are contained within the upper casing 11, which can be separated from the lower casing 10 by slightly turning it relative to the lower casing 10. After this slight turning step, the upper container 11 and its contents are lifted from the lower container 10 and the drive shaft 15 is extracted from the socket 16 forming part of the mixing vane 14. The mixing vane 14 and container 13 are then removed from the lower casing 10 for cleaning.

A battery container 17 made of a heat insulating material is provided within the upper casing 11. For this reason, 8 rechargeable batteries 18 are used during operation of the ice cream machine.
The small amount of heat generated by this function is retained. A rechargeable battery 18 is connected to socket 2 by an electrical circuit.
1, and a battery charger is connected to this socket when the battery 18 needs to be recharged. A small electric motor 22 serves to drive the drive shaft 15 via a reduction gearing system which will be described in more detail below with respect to FIG. Two fans 23 and 24 are juxtaposed just above the opening surface of the container 13. The fans are each driven by a small separate electric motor housed in the hub of the fan, and the fans draw air through the openings 25 into the upper casing 11 and fall onto the surface of the ice cream mixture in the container 13. The air then flows around the container 13 and out through the opening 26 in the bottom of the lower casing 10.

Although improved results can be obtained by using a single fan located just above the opening of the container, even better results can be obtained by using two fans side by side as shown. Although the exact cause is not known, the results obtained with two diametrically spaced fans are not as good. The concentration of cold air hitting the ice cream surface produced by the two juxtaposed fans forms a frozen crust on the ice cream immediately below the fans, which crust is then incorporated into the mixture by the action of the mixing vanes 14. Regardless of whether things are right or wrong, experience has shown that the use of two fans yields very good ice cream in a time that is within the capacity of the battery 18.

Battery 18, motor 22 and motor drive fan 2
3 and 24 are connected to an electric circuit (not shown), and this circuit is controlled by an on/off switch that can be operated from the top of the upper casing 11. This electric circuit consists of four batteries connected to two fans 23 and 2.
The four motors are used to drive the four motors, and the four motors are configured to be used to drive the motor 22.
The fan's motor absorbs less energy than the motor 22, and this configuration ensures that the fan continues to operate after the mixing vanes 14 stop rotating.

The motor 22 drives the shaft 15 into a pinion gear 28,
It is driven through a reduction gearing consisting of 31, 32, 33, 34, 35, 36, 37 and 38, the configuration of which is clearly shown in the detailed view of the transmission shown in FIG. Between the pinions 36 and 37 there is provided an articulating clutch 41 which is spring-loaded with a coil spring 42.
As the ice cream mixture becomes frozen solid, the resistance to movement of the mixing vane 14 increases, and when this resistance reaches a certain level, the clutch 41 begins to slip and the mixing vane comes to rest. For this reason,
When the mixing vane stops moving, the motor 22 will not be damaged by heating. As mentioned above, the fans 23, 24 continue to rotate even after the mixing vanes have stopped and shut down. The slip of clutch 41 provides an audible indication that the ice cream production is complete.

As can be seen in FIG. 4, the blade 14 has a complex shape, and its lower part has a contour that matches the internal shape of the container 13, as is also apparent in FIG. The vane is made by molding of plastic material and has a central socket 16 surrounded by an annular portion 43 from which a portion 44 extending radially upwardly projects.
A circumferentially extending sloping portion 45 extending at an angle of approximately 45° to the bottom of 3 is coupled thereto. A leading vertically extending portion 46 extends from the top to the bottom of the vane and is supported at the bottom by struts 47.

The shape of the blade was obtained empirically with a special intention to produce the effect shown in Figure 5. As can be seen from Figure 5, the rotation of the blade in the ice cream mixture causes the ice cream to A gap, as shown at 48, is formed between the cream mixture and the outer wall of the container 13, and a gap, as shown at 49, is formed between the ice cream mixture and the inner wall of the container, respectively. The illustration shows the morphology of the ice cream at a much later stage during ice cream formation, when the ice cream mixture has become relatively firm. Although the patented device differs somewhat during the initial stage when the ice cream mixture is more liquid, the purpose achieved by the special shape adapted to the blades is that the ice cream mixture is not merely stirred as the mixing blades rotate. Instead, a gap is formed between the ice cream mixture and the container through which air from the fans 23 and 24 can pass.

In use, container 13 is filled with a liquid ice cream mixture. The two parts 11, 12 of the container are then joined together, the drive shaft 15 inserted into the socket 16, and the two parts connected by the bayonet joint 12.
Next, the entire machine is inserted into the freezing chamber of the refrigerator, and the switch 26 is turned on to start the motor. Mixing vanes 14 are continuously rotated by motor 22 and fans 23, 24 direct an air stream over the surface of the ice cream mixture. After about 45 minutes, the ice cream mixture is sufficiently firm to cause the clutch 41 to slip, thereby providing an indication for removal from the freezer compartment of the machine. The two halves of the container are then separated and the ice cream is removed directly from the container 13. After that, the container 13 and the blade 14 are taken out for cleaning, and the battery charger is inserted into the socket 2.
1 to recharge the battery pack for next use.

[Brief explanation of drawings]

Fig. 1 is a central sectional view of the ice cream making machine of the present invention, Fig. 2 is a plan view of the machine with the upper cover partially cut away to show the parts directly below, and Fig. 3 is a detail of the transmission gear train. Figures 4a and 4b are drawings of the mixing vanes, and Figure 5 is a schematic plan view of the container showing the effect of the rotating vanes in the ice cream mixture. 13...Thin container, 14...Mixing blade, 15...
...Drive shaft, 16...Socket, 18...Battery, 2
1...Socket, 22...Small motor, 23,2
4... Juan, 28, 31, 32, 33, 34,
35, 36, 37, 38...reduction gear train, 41...
…Occlusal clutch.

Claims (1)

[Scope of Claims] 1. A household ice cream making machine that can be inserted into a refrigerator, comprising a container in the form of an annular trough having a shaft, and a container arranged in the trough so as to be rotatable around the axis. a mixing vane, an electric motor device drivingly connected to the vane for rotating the mixing vane, and a device for creating a downwardly directed flow of air over the surface of the ice cream mixture in the container;
An outer case surrounding the container, the case being formed to define a passage around the container and an outlet below the container, so that air leaving the surface of the ice cream mixture passes around the container and through the outlet. A household ice cream making machine characterized by being oriented as follows. 2. A household ice cream making machine according to claim 1, wherein the device for creating the air flow comprises a fan placed above the container and a motor device placed to rotate the fan. 3. The household ice cream making machine according to claim 2, wherein two fans are placed side by side. 4. The household ice cream according to any one of claims 1 to 3, wherein all of the electric motor devices are powered by a battery pack consisting of a plurality of batteries housed in the ice cream making machine. machine. 5. The home ice cream making machine according to claim 4, wherein the electric motor device for driving the mixing blade and the electric motor device for driving the fan are powered by batteries from different groups of a battery pack. 6. The mixing vanes separate the ice cream mixture from the inner and outer walls of the container as they rotate, thereby creating a circumferentially and axially extending gap between the ice cream mixture and the walls of the container through which the air flow can pass. A household ice cream making machine according to any one of claims 1 to 3, constructed and arranged as follows. 7 The first mentioned electric motor device drives the mixing vanes via a gear train including a spring-loaded mating clutch;
According to any one of claims 1 to 3, the interlocking clutch is configured to slip when the consistency of the ice cream mixture reaches a predetermined level during freezing. Home ice cream making machine described.