An auger for an ice cream mixing apparatus
The invention relates to an auger for an ice cream mixing apparatus for mixing ice cream with one or more flavour additives, the ice cream mixing apparatus comprising a funnel for holding the ice cream and the flavour additives, an auger driver for rotating the auger, and a linear actuator for relative movement of the funnel and auger into a position in which the auger is telescoped into the funnel, in which position a rotation of the auger will mix the ice cream and the flavour additives.
The ice cream will normally be in hard form, and will normally be supplied in small, rather hard blocks. The flavour additives may be supplied as particles, e.g. chocolate powder, as hard pieces, e.g. nuts, as soft pieces, e.g. pieces of an apple or an orange, or in liquid shape, e.g. strawberry jam. The result of such a mixing is a semiliquid ice cream in which the flavour additives are more or less distributed. The ice cream is poured out of the funnel, into a cup or an ice cream cone, and sold to consumers.
Such apparatuses are known from a number of patents. US 4 548 054, US 4 637 221 , U S 4 708 489 and US 4 974 965 all describe machines or apparatuses comprising an auger or agitator with a helical thread or cutter extending into a funnel or container for holding the ice cream and additives. The auger and funnel is relatively rotatable, and after some rotation the ice cream and additives have obtained a semiliquid condition which is attractive to consumers.
Generally there are three tasks to be carried out in the ice cream mixing: The first task is to soften the ice cream, and make it suitable for mixing with the flavour additives and pouring out of the funnel. The second task is to mix the ice cream and the flavour additives in a way which make the result attractive to the consumers. The preferred mixture consists of a softened ice cream in which the flavour additives are evenly distributed. In some applications it is preferred that bits of the flavour additives are found in the ice cream. The third task is to force the ice cream mixture out of the funnel, i.e. the auger must produce an extruding action.
It has been found that prior art augers do not carry out all these task in a satisfactory way. The object of the invention is to provide an auger for an ice
cream mixing apparatus which is improved with respect to the above mentioned tasks.
The object is achieved by an ice cream mixing apparatus as mentioned in the introduction, characterized by the features of the claims. The invention thus consists of an auger for an ice cream mixing apparatus for mixing ice cream with one or more flavour additives, the ice cream mixing apparatus comprising a funnel for holding the ice cream and the flavour additives, an auger driver for rotating the auger, and a linear actuator for relative movement of the funnel and auger into a position in which the auger is telescoped into the funnel, in which position a rotation of the auger will mix the ice cream and the flavour additives. The auger is provided with a thread with at least one discontinuity, causing a combined mixing and extruding action. It has been found that this improves the functionality of the auger with respect to softening the ice cream, mixing the ice cream and the flavour additives in a way which make the result attractive to the consumers, and force the ice cream mixture out of the funnel, as discussed above.
Improved functionality is achieved with an auger according to preferred embodiments of the invention.
Preferably the at least one discontinuity forms a slot allowing ice cream to pass transverse the thread. It is further preferred that the termination of the thread adjacent the discontinuity forms a curved lip. at least on one side of the discontinuity. Preferably the termination of the thread adjacent the discontinuity forms a curved lip on both sides of the discontinuity, the lips pointing essentially in opposite directions. The thread preferably has a number of discontinuities essentially aligned in the longitudinal direction of the auger. Preferably the thread has a waveform, preferably with a variable curvature along the circumference of the auger. It is further preferred that the thread has steep rises opposite the discontinuities.
The width of the thread preferably decreases towards the apex of the auger. Further, the thread preferably has a variable pitch, decreasing towards the apex of the auger. In a further preferred embodiment the thread pitch is decreasing towards the apex of the auger, however, the pitch between the top and the second top flights is the smallest.
It is also preferred that the apex of the auger is provided with a knife for cutting flavour additives during forcing the additives through an outlet of the funnel.
The invention will now be explained by a description of a preferred embodiment and some variants with reference to the accompanying drawings. In the drawings:
Fig. 1 is a schematic side view of an ice cream mixing apparatus with an auger outside the funnel.
Fig. 2 is a side view of an auger according to the invention. Fig. 3 is a side view of an alternative auger according to the invention.
Fig. 4 is a side view of an alternative auger according to the invention.
Fig. 5 is an opposite side view of the auger in fig. 4.
Fig. 6 is a plan view of a knife to be used with the auger.
Fig. 1 is a schematic side view of an ice cream mixing apparatus for mixing ice cream with one or more flavour additives, illustrating the principal parts. The ice cream mixing apparatus comprises a frame 25 with a foot 26 for placing on a not illustrated support, e.g. a table. A funnel 2 for holding the ice cream and flavour additives is supported by an auger bearing box 34. which is supported by the frame 25. An essentially vertical auger 3 with its spindle 4 is rotatably supported by journal bearings in the auger bearing box 34, and axially supported by a driver bracket 24. The driver bracket 24 also supports an auger driver 5. which consists of an auger motor 23 and a sheave/belt transmission 22 for transferring rotational movement to the auger spindle 4. The funnel 2 forms part of an enclosure 8 with a closable inlet 9 which is slanting upwards, and which can be closed by a lid 35 which is hinged to the inlet 9 in a hinge 36. A funnel outlet 20 with an ice cream nozzle 38 points at a cup 32 which is placed in a cup holder 56. The cup holder is perforated to allow wash water and spilt ice cream to flow to a sink 33 and further to a drain conduit 57.
A linear actuator 6, which may be a pneumatic cylinder, or preferably an electrically operated linear actuator, is attached to the apparatus frame 25 via an actuator bracket 37. An actuator rod 27 extends vertically from the linear actuator 6, and is connected to a spring means 39 in a lower spring attachment 41. The spring means 39 is attached to the driver bracket 24 in an upper spring attachment 40, and thus the spring means 39 is arranged between the linear actuator 6 and the driver bracket 24. The driver bracket 24 is attached to a slide bracket 3 1 which via a rail 30 which is fixed to the frame 25 is slidingly guided in a vertical direction, illustrated by an arrow 42.
In fig. 1 the spring means 39 is illustrated in its retracted position. Corresponding stopper elements formed by a stopper bar 28 on the actuator rod 27 and stopper bolts 29 on the driver bracket 24 are in engagement and prevents a retraction of the spring means 39 beyond its retracted position. In this position the spring means 39 is somewhat pretensioned. in order to prevent play during initial extension of the spring means.
In fig. 1 the linear actuator 6, i.e. the actuator rod 27. is illustrated in an upper position, and the auger 3 is illustrated in a corresponding position outside the funnel 2. An activating of the linear actuator 6 causes the actuator rod 27 to move down, in the direction illustrated by arrow 42. The movement of the actuator rod 27 is via the spring means 39 transferred to the driver bracket 24, causing the driver bracket with the sheave/belt transmission 22, the motor 23 and the auger spindle 4 to move down, in the direction of the arrow 42. The auger 3 thus moves down as illustrated by arrow 7, and hits a block of ice cream 1 which is located in the funnel 2. If the ice cream is hard, which it normally will be to a certain extent, a further movement of the auger 3 will be prevented, causing an extension of the spring means 39. A further movement of the actuator rod 27 in direction 42 will further extend the spring means 39, which exerts a tension force which tries to force the auger 3 into the ice cream 1.
The auger 3 is simultaneously rotated, which softens the ice cream 1. The spring means retracts and forces the auger 3 into the ice cream 1 , and after some time the auger 3 is telescoped into the funnel 2. When the end 21 of the auger 3 reaches the bottom of the funnel, the spring means 39 will again be in the retracted position, and the stopper bar 28 and the stopper bolts 29 will
again be in engagement. A reversing of the linear actuator 6. i.e. a movement of the actuator rod 27 in the direction opposite the arrow 42, will withdraw the auger 3 from the funnel 2.
Fig. 1 also illustrates a spray nozzle 10 for pointing a water spray at the auger 3 for washing purposes. A vane wheel 14 is located in a transition area between the auger 3 and the auger spindle 4, causing a deflection of the water spray during a movement of the auger 3 past the spray nozzle 10. A heated water supply 16, a cold water supply 17 and a liquid detergent supply 18. in which liquid detergent is supplied from a liquid detergent container 53 via a pump 54, and corresponding not illustrated control valves, allow various spraying concepts to be used for washing or rinsing the enclosure 8 and the auger 3 between the ice cream mixing.
The ice cream mixing apparatus also includes electric circuitry with a programmable electronic control unit, a power supply, switches, pushbuttons and lamps. In order not to overload figure 1 , these items are left out. The electronic control unit may include microelectronics for both manual and automatic activation of the linear actuator, switches, lamps, motors and control valves. The automatic activation can be based on input from sensors or a timer and include sequencing of functions. These items as well as their functioning and physical arrangement are conventional.
In use the operator puts a charge of ice cream 1. typically hard ice cream, and a charge of flavour additive, typically fruit, berries or nuts (not illustrated), into the inlet 9. He then pushes a button which activates the auger motor 23 and the linear actuator 6, and the auger 3 enters the funnel 2. as explained above. The rotation of the auger 3 causes a mixing of the ice cream 1 and the flavour additives into a semiliquid mixture which after a certain time. e.g. 5 seconds, is poured out through the outlet 20 and into the cup 32 for consumption. The nozzle 38, which may have the shape of e.g. a star, gives the ice cream mixture the desired shape. Fig. 2 is a side view of an auger 3 according to the invention, comprising a shaft 80 which can be securely attached to the auger spindle, and a helical thread 70 which ends in an apex 75. The thread 70 has three discontinuities 71 , aligned in the longitudinal direction of the auger 3.
It has been found that the discontinuities 71 improve the functionality of the auger with respect to softening the ice cream. It has further been found that the discontinuities 71 provide a mixing of the ice cream and the flavour additives in which the flavour additives, e.g. nuts or pieces of fruit, are evenly distributed, which make the resulting ice cream mixture attractive to the consumers. Further it has been found that the auger according to the invention produces an extruding action which forces the ice cream out of the funnel.
Preferably the discontinuities 71 forms slots allowing ice cream to pass transverse the thread 70.
Fig. 3 is a side view of an alternative auger 3 according to the invention, in which the width w of the thread 70 decreases towards the apex 75.
Fig. 4 is a side view of a preferred alternative auger 3 according to the invention. In this auger terminations 72 of the thread 70 adjacent the discontinuities 71 form curved lips 73. The curved lips may be on one side of the discontinuities 71 only. or. as illustrated, on both sides of the discontinuities. The lips 73 point essentially in opposite directions.
Fig. 5 is an opposite side view of the auger in fig. 4. It is here illustrated that the thread 70 has a waveform, with a variable curvature along the circumference of the auger 3. and steep rises 74 opposite the discontinuities 71.
Fig. 5 further illustrate that the thread 70 has a variable pitch p j -p5, decreasing towards the apex 75 of the auger 3. It can be seen, which is preferred, that the pitch p4 between the top flight 76 and the second top flight 77 is the smallest.
In order to cut flavour additives when forcing the additives through the outlet 20 of the funnel 2, it is preferred that the auger 3 comprises a knife 78 at the apex 75, as seen in fig. 4 and 5.
The auger may be produced by moulding a suitable plastic. Fig. 6 is a plan view of the knife 78. illustrating a cross-shaped knife with edges 79 and a central hole 81. The knife is preferably made from stainless
steel and attached to the apex 75 of the auger 3 by a bolt through the central hole 81.
The invention has in the above been described with reference to augers with certain numbers of discontinuities. It should be understood, however, that the number of discontinuities may vary according to the specific design. Further the inventive auger has been described as forming a part of a particular ice cream mixing apparatus. It should be understood, however, that the invention may be used as a part of any ice cream mixing apparatus defined by the claims and its equivalents.