Method and an apparatus for the production and dispensing in portions of noncarbonated mixed drinks

A method and an apparatus are proposed in order to eliminate the influence f viscosity variations in the syrup on the accuracy of metering in vending machines for the production and dispensing of still mixed drinks by considerably raising the injection pressure for the water, to eliminate the effect of the susceptibility of these syrups to spoilage by intentional aeration of the injection zone in the case of mixed drinks based on citrus syrups, and at the same time to keep the pulp particles of the citrus syrup in a desired state of suspension in the prepared mixed drink by intentional introduction of a predetermined quantity of air during the dispensing process, while avoiding foaming and clouding of the mixed drink by intentionally cutting off the introduction of air in the case of mixed drinks based on clear syrups, without the raised injection pressure having to be omitted even with these syrups.

FIELD OF THE INVENTION 
The invention relates to a method of producing and dispensing portions of 
noncarbonated (quiescent) mixed drinks from fruit syrup and water in which 
the fruit syrup is sucked up by a compressed water jet by the injection 
pump principle, is mixed with the water and the mixture is dispensed. 
BACKGROUND OF THE INVENTION 
Methods and vending machines for the dispensing in portions of 
noncarbonated mixed drinks have been known for a long time. The fruit 
syrup is usually cooled and is mixed with water, usually tap water, 
directly during the dispensing operation. In vending machines, it is 
usually possible to choose between noncarbonated mixed drinks of differing 
flavors. The choice basically lies between the citrus line (lemon, orange, 
pineapple) and the line of clear drinks based, for example, on apple syrup 
or the like. The two lines differ essentially in that the citrus line uses 
syrups or concentrates which also contain a considerable amount of pulp 
and lead to cloudy drinks, while the other line uses essentially syrups 
which lead to clear mixed drinks. Moreover, the citrus syrups are very 
susceptible to spoilage and must therefore be cooled, for example, to 
between 4.degree. and 5.degree. C. 
Another problem in the production of noncarbonated mixed drinks lies is 
that the viscosity of the syrups and concentrates varies with temperature. 
As a change in the syrup temperature within certain limits cannot be 
prevented with a justifiable outlay for cooling, in spite of the cooling, 
inaccuracies occur in metering and therefore there are variations in the 
consistency and quality of the mixed drink. These variations cannot be 
compensated at the normal injection pressure which is predetermined by the 
line or top pressure and can be at least 1.5 bar. 
An elevation in the injection pressure also fails to solve the problem 
because a high pressure causes foaming and clouding in the case of mixed 
drinks using syrups in the clear line, so that apple juice as dispensed 
can give the impression that it is beer. 
For this reason, an injection pressure of approximately 1.5 bar has been 
maintained in the dispensing of noncarbonated mixed drinks in vending 
machines and attempts have been made to overcome the other problems by 
additional cooling and control. 
OBJECTS OF THE INVENTION 
The object of the invention is to remedy these problems and provide a 
method and an apparatus with whose aid the above-mentioned problems can be 
overcome, by means of which the accuracy of metering can be made 
independent of viscosity variations without additional expense, which 
markedly reduces the risk of spoilage with drinks of the citrus line and 
which also ensures that cloudiness due to foaming is avoided in the case 
of noncarbonated mixed drinks. 
With pulp-containing syrups, there is also a risk that the pulp particles 
in the glass in the prepared mixture either settle on the bottom of the 
glass or float to the surface of the drink. Both situations are 
undesirable. It is, therefore, another object to ensure that pulp 
particles of the juice or concentrate are kept in suspension in an almost 
homogeneous distribution in the liquid content. This should also be 
achieved by the new method and the corresponding new apparatus. 
SUMMARY OF THE INVENTION 
These objects are achieved in accordance with the invention whereby with 
pulp-containing syrups, some air bubbles which keep the particles in 
suspension are attached to the pulp particles in the injection zone. This 
prevents the pulp particles from rising to the surface of the liquid or 
from settling on the bottom of the glass so that the drink maintains its 
initial approximately homogeneous mixed state even after prolonged 
standing. 
As syrups of the citrus line and syrups of the clear drinks line are 
usually processed in vending machines, the method for the production and 
dispensing in portions of noncarbonated mixed drinks of the invention is 
carried out so that the water is conveyed through the injection zone at a 
pressure considerably exceeding the normal line pressure and, in the case 
of syrups which are low in pulp or clear, the injection zone is kept 
partially filled with the syrup between two dispensing processes and, in 
the case of syrups which are rich in pulp or cloudy, the injection zone is 
freed from syrup remains after each dispensing process and is kept 
partially filled with air and this air is then mixed intensively with the 
syrup and the relevant quantity of water during the next injection 
process. Injection pressures of between 1 and 6 bar have proven 
advantageous. 
All problems which formerly occurred due to viscosity variations have 
essentially been avoided at the raised injection pressure without the need 
for measures to prevent the actual viscosity variations. 
In conjunction with the other measures according to the invention, the 
raised pressure also causes the quantity of air available while processing 
syrups of the citrus line to be introduced intensively into the mixture so 
that this air is attached in very fine bubbles to the pulp particles of 
the syrup and the processes are controlled in such a way that the pulp 
particles reach a state of suspension in the prepared mixture in the 
glass. 
The necessary air is provided in a very simple manner by emptying the 
injection zone of syrup remains after each injection process, these 
remains being introduced into the mixed drink just dispensed. At the same 
time, this eliminates the problems usually caused by the susceptibility of 
the citrus syrups to spoilage. The residual quantities still remaining in 
the injection metering apparatus after emptying the syrup remains are 
extremely small and generally are at such a high sugar concentration that 
problems of hygiene do not arise. 
With the almost complete emptying of the injection zone of the citrus 
syrup, the desired quantity of air is at the same time kept in readiness 
in an approximately dimensioned injection zone for the next injection 
process, which air is intensively mixed with the water and the syrup in 
the injection zone by the water jet introduced under elevated pressure. 
However, it is also possible to adopt the elevated water pressure of 
between 1.5 and 6 bar in the processes for dispensing syrups of the clear 
syrup line without the formerly feared risk of foaming and clouding of the 
mixed drink arising. This is achieved without great expense by keeping the 
injection zone filled with the clear syrup after each injection process in 
this case. As the clear syrup is considerably less susceptible to 
spoilage, no additional problems arise as the residual cooling is 
sufficient for the requirements of hygiene. The filling of the injection 
zone with syrup prevents air from being injected into the mixture during 
the next dispensing process in spite of the considerably elevated water 
pressure. Extremely slight bubbling and therefore virtually no foam and no 
cloudiness are obtained in spite of dispensing at elevated pressure. 
For carrying out the method, the invention uses an apparatus in a vending 
machine for the production and dispensing in portions of mixed drinks, 
which is equipped with a water jet injection pump with a connection for 
water, in particular tap water, and connections for fruit syrup and with 
an outlet for the mixture downstream of the injection zone. In this 
apparatus a pump which raises the water pressure above the normal line 
pressure is arranged upstream of the water connection and the injection 
zone is provided with a controllable aeration valve. The aeration valve is 
preferably arranged between the connection for water and the pump and is 
controllable in such a way that it is closed during each injection 
process, but is opened before the end of the dispensing process in the 
case of syrups rich in pulp after closure of the water supply. 
Despite its simple structure, the new arrangement operates extremely 
reliably and allows greatly differing processes during dispensing by the 
mixing in of air in the case of syrups of the citrus line or clearing of a 
mixed drink based on clear syrups without great expense, the problems of 
hygiene in the dispensing of citrus drinks at the same time being solved 
in a simple manner and the variations in the prepared mixed drink formerly 
occurring due to viscosity variations being reliably eliminated without 
great expense. 
The term "vending machines" also includes those which operate without 
coins, which are also known as "dispensers".

SPECIFIC DESCRIPTION 
The apparatus can be arranged in a vending machine and can be identical in 
design for the dispensing of drinks based on citrose syrups and based on 
clear syrups. 
The apparatus can be connected to a conventional water pipe at 1. The water 
is therefore supplied at the conventional water pressure according to the 
arrow. However, the water can also be stored substantially pressure-free 
in a water collecting tank in the vending machine and be removed as 
required. A pump 2 which raises the pressure of water above the normal 
line pressure to a pressure of between 1.5 and 6 bar is arranged in the 
supply pipe 1. The water at the elevated pressure is conveyed via a pipe 
section 4 to the connection 8 of a water jet injection pump 15. The tube 
of the water jet pump is shown cut away so as to give a view of the 
interior. The jet tube 9 through which the water jet is conveyed through 
the injection zone 10 into the nozzle 12 is shown. The cross-section 
widens downstream of the nozzle 12. The dispensing tube 13 from which the 
mixture is conveyed along the arrow into a beaker or the like is shown at 
the bottom end. The suction tube 11 for the syrup which is supplied as 
represented by an arrow from a cooled device (not shown) for the syrup 
opens obliquely from below into the injection zone 10. 
The pump 2 which elevates the water pressure can be connected via a 
switching device 2a and a pipe 3 to a central control device on the 
vending machine. 
In the example illustrated, the intermediate pipe 4 has a branch 4a which 
is connected via a valve 6 which can be controlled by an electromagnet 7 
to a fitting 5 which communicates along the arrow with the surrounding 
air. The solenoid can also be connected via a pipe 7a to the central 
control unit of the vending machine. 
If the apparatus illustrated is used for dispensing mixed drinks based on 
citrus syrups, the syrup is sucked by the water jet via the pipe 11, mixed 
intensively with the water in the injection zone 10 and conveyed through 
the nozzle 12 into the dispensing tube 13. At the end of the dispensing 
process, for example, the pump 2 is stopped via the central control device 
and the water supply therefore terminated. At the same time, the aeration 
valve 6 is opened via the electromagnet 7 so that the injection zone 10 
can be freed from the syrup remains and the water remains via the 
discharge tube 13 by running empty. These remains are entrained into the 
delivered portion. When the next dispensing process is triggered, the 
valve 6 is closed and the pump 2 started up so that only the quantity of 
air in the actual apparatus is mixed intensively into the mixture of water 
and syrup with the starting injection process. The air is broken down into 
very fine bubbles and attaches itself to the pulp particles of the citrus 
syrup. The quantity of air is calculated in such a way, in conjunction 
with the elevated water pressure, that the pulp particles in the prepared 
mixed drink are kept in suspension through the attached bubbles for a 
prolonged period. 
When using the apparatus for dispensing mixed drinks based on clear syrups, 
the arrangement is controlled in such a way that, at the end of the 
dispensing process, the syrup sucked through the water jet in the 
injection zone 10 and the subsequent nozzle 12 remains approximately at 
the level of the line 14. Delivery is not possible since aeration of the 
interior of the apparatus does not take place. The injection zone 10 and 
the connected internal volume of the apparatus therefore remains filled 
with liquid so that no air is present. This state is maintained until the 
next dispensing process, which also takes place at the elevated water 
pressure through the pump 2. As no significant quantities of air are 
present, bubbles cannot be produced and foaming and therefore clouding of 
a mixed drink cannot occur. 
Depending on the quantity of air required for producing the state of 
suspension of the pulp, the point where the aeration valve 16 is attached 
to the apparatus can be higher or lower. It can also be attached directly 
to the housing tube of the water jet injection device 15. 
It is thus possible to determine the quantity of air which is introduced 
into the mixed drink during the injection process according to the 
selected injection pressure of the water and pulp content or type of pulp, 
so that the desired state of suspension can be achieved in a simple manner 
for each type of syrup. 
Viscosity variations have no effect as they are compensated by the 
correspondingly elevated water pressure and therefore injection pressure. 
The new apparatus can also be fitted subsequently on to earlier devices 
based on the injection principle, as the interposition of a pump which 
raises the pressure and the installation of the aeration device can 
usually be carried out later on without difficulty.