FR2607515A1 - Improvement to pulsing wine presses suitable for obtaining quality wines - Google Patents

Abstract

Improvement to horizontal wine presses suitable for obtaining quality wines, characterised in that, in a wine press of the so-called "pulsing wine press" type, the circuit for controlling the motor which rotates the feed and compression screws includes a current limiter KA combined with a delay system KT.

Description

 The present invention relates to an improvement made to impulse presses with a view to obtaining quality wines delivered in particular under the appellation A.O.C.

In the wine sector, we already know the continuous presses, which are widely used. These presses are based on the principle briefly recalled below with reference to the diagram of Figure 1 attached
The harvest (V) admitted by the feed hopper (6) into the body of the press (P) is continuously driven by two Archimedes screws (1-2) mounted on the common axis (A) controlled in rotation by a motor (not shown). The first of these screws (1) is called "drip screw" and it fulfills its role in a chamber (E) called "drip chamber" while the second (2) called "compression screw" fills its own in a chamber (C) called "compression chamber". These two chambers (EC) are separated by a diaphragm called "bivalve" (3) comprising two symmetrical openings (3a-3b) relative to the axis (XY). An exit door (4) is provided for evacuation , through the trough (G), of the "plug" formed in the compression chamber (C) as will be seen below
The dripping screw (1) causes, by its rotation in the chamber (E), the displacement of the harvest inside this chamber, the flow of the juice through a perforated plate (T) provided at the lower part of the chambers (EC) and passes the harvest through the "bivalve" (3) in the compression chamber (C). The compression screw (2) during its rotation and due to a continuous supply of an imperfectly cleared volume of grape harvest has the role of increasing the pressure inside the compression chamber thus causing the extraction of the remaining juice through the perforated sheet T. This latter comprises, moreover, suitable filtration systems not shown in FIG. 1.

 The "bivalve" diaphragm (3) is designed in a way (which need not be described in detail here) to prevent the backflow of the harvest when the pressure increases in the compression chamber (C). Note that in this classic continuous press, the Archimedes' screws (1-2) are in permanent rotation. It is then found that the rotation of the compression screw (2) which is in contact with the harvest during pressing has the consequence of somewhat degrading the harvest by causing the formation of "muds" mixed with the grape juice. This is the reason that motivated the ban on this type of press for the production of quality wines. This is also the reason why the so-called "impulse" presses were developed.

 This type of press and their operation are described below with reference to the diagrams illustrated in Figures 2 to 5 attached (the same elements or bodies bearing the same references as in Figure 1).

The modification made compared to the continuous press previously described consists in allowing
- the momentary rotation stop of the Archimedes screws (1-2) and
- to print a translational movement of the compression screw (2) while the feed screw (1) is immobilized. This is achieved by means of a hydraulic cylinder (5) mounted at the end of the common drive shaft (A), which, in engagement with the compression screw (2) through the feed screw (1) causes said compression screw (2) to slide.

The operation of this type of press is then as follows with a three-stroke cycle
1st stage: draining and filling of the compression chamber
The two screws (1-2) are in rotation, the compression screw (2) being attached to the bivalve diaphragm (3).

(See figure 5).

2nd step: Pulse pressing
After a predetermined time using a timer, the rotational movement of the two screws is stopped.

The compression screw (2) advances towards the exit door (4) by pressing the harvest between its last turn and the stopper (B) already formed (Figure 2), the advancement of the latter being controlled by the door outlet (4) (Figure 3).

3rd time
- rotation of the two screws (1-2) and simultaneous return to its starting point of the compression screw (2) (Figure 4).

Such an arrangement and operation already represent a significant improvement compared to the conventional continuous press since the rise in pressure in the compression chamber takes place with a screw (2) at a standstill. However, practice shows that this improvement is not sufficient for this type of press to be authorized for quality wines because
- the setting of the timer is "judged" without precise control of the pressure inside the compression chamber (C)
- Nothing prevents the user, by setting the timer to its maximum, from operating continuously without going through the "pulse" phase, which amounts to operating the press 13 like a continuous press.

The present invention proposes to overcome these drawbacks and provides an improvement to the type of so-called pulse press.
The improvement according to the invention is based on the fact that it appeared that the torque necessary for the rotational drive of the compression screw (2) was directly a function of the pressure prevailing inside the compression chamber (VS) ; it follows, consequently, that the value of the current intensity for the supply of the electric motor controlling the rotation of this compression screw (2), according to a given rotation speed, was also directly a function of said torque required to drive said compression screw (2) in rotation. The present invention therefore aims to control the pressure inside the compression chamber by adjusting the intensity of the current absorbed by the electric drive motor. of this compression screw. This is what constitutes the improvement which is the subject of this request.

 Thus, this improvement is characterized by the fact that, in a press of the type known as "pulse press", the motor control circuit ensuring the rotation of the supply and compression screws comprises a current limiter combined with a timer system.

Other characteristics and advantages of the invention will emerge more clearly from the description which follows, given with reference to the appended drawings in which, in addition to FIGS. 1 to 5 which have been previously presented and commented on,
FIG. 6 represents an electrical diagram comprising the improvement according to the invention and
- Figures 7 to 9 show curves of the variation in the intensity of the supply current of the drive motor of the screws of a press, as a function of time, during operation respectively of a continuous press, d 'an impulse press and an improved press according to the invention.

Referring to these figures:
- supplying the line (C1-Cla-Clb), by closing the K3M contact, causes the motor to start (not shown) ensuring the rotation of the screws;
- the supply of the line (C2-C2a-C2b), by closing the contact K2M causes the starting of the motor not shown ensuring the translation of the compression screw.

 According to the refinement of the invention, the control circuit comprises, bypass, an intensity limiter KA (illustrated in the figure) connected to a timer (KT) which, when the intensity reaches the maximum fixed, closes the contact K3M and opens the K2M contact.

 The role and function of a circuit thus modified will appear to those skilled in the art by comparing the shape of the curves in FIGS. 7 to 9.

In a continuous type press (Figure 7), after the start-up phase (OM), the first level (AB) corresponds to the supply phase of the compression chamber. The intensity is constant since the screw drive motor (1-2) must
- on the one hand, overcome the constant friction resistances, and
- on the other hand, simply move the harvest from the drip chamber (E) to the compression chamber (C).

 During the course of the operation, the intensity increases (BC) when the pressure in the compression chamber increases. A second level is then reached (CD) when the pressure in the compression chamber is sufficient to cause the expulsion of the plug.

 In a pulse press, after the start-up phase (oM), the first level (AB) followed by the pressure build-up (BC), the rotation of the screws (1- 2) and the transition to the pulse phase (CNPS) according to the previously described operating phases.

 The backward movement of the jack results in the pressure variation (SRA) before starting a new phase of feeding the harvest (new bearing AB).

With a properly set timer, the pulse phase is triggered (intensity-pressure variation GHJK) before the pressure reaches the pressure corresponding to the second pressure level (CD), which would be reached with an incorrectly set timer (time too important). Such a pressure level would be detrimental to the quality of the harvest in contact with the rotating screw.

 In the extreme case, the CD level reached can be reached and maintained for a certain time.

 On the other hand, with the improvement according to the invention, after the start-up (OMA) and feeding (AB) phases, as soon as the intensity reaches a level (EF) which one judges should be detrimental to the harvest, the intensity limiter KA with its timer KT acts to open the contact K3M (previously closed) and stop the supply of the motor ensuring the rotation of the screws.

We then go to the impulse phase by closing the K2M contact (previously open) with evacuation of the plug (ENPS), then to that of the backward movement of the jack (SRA) to resume the supply phase and rise in pressure (ABF) ( closing of K3M and opening of K2M), followed by the impulse phase (FHJK).

 Thus, at no time, there is a risk of reaching the CD level for which the press would operate in continuous press with a rotating screw causing the expulsion of the plug.

 In the case of the present invention, the expulsion of the plug is caused during the pulse phase with a screw which does not rotate.

 Thus the advantages resulting from the improvement of the invention reside in the fact that there is a limitation of the pressure on the outlet cylinder; to a limitation of the intensity of the motor causing the rotation of the screws to a value such that the pressure in the compression chamber does not deteriorate the harvest and finally to a stop of the rotation movement of the screws causing the automatic transition to the phase impulse.

 It goes without saying that the present invention has been described and illustrated for purely explanatory and in no way limitative and that any useful modification, in terms of equivalences, may be made without departing from its scope.

Claims (1)

 CLAIM  Improvement in horizontal presses suitable for obtaining quality wines, characterized in that, in a press of the so-called "impulse press" type, the motor control circuit ensuring the rotation of the supply and compression screws ( 1-2) has an intensity limiter (KA) combined with a timer system (KT).