EP0308723B1 - Filling head for beverage filling equipment - Google Patents

Abstract

A filling head for counterpressure beverage filling, in which, between the filling processes, the gas channel is blown out by opening the gas valve in order to remove drops sticking in the gas channel, has a throttle in the gas channel in order to lower the gas consumption during the blowing out. <IMAGE>

Description

The invention relates to a filling element of the type mentioned in the preamble of claim 1.

Such a filling element is known from FR-E-92742.

Filling elements of this type have a gas channel which, when the bottle is placed underneath, connects the interior of the container to the gas space of the boiler. In the case of filling devices of the type mentioned at the outset, this gas channel is essentially required for two purposes, firstly for prestressing the container and secondly as a return gas channel.

The gas valve is opened before the start of filling in order to pretension the container with the boiler pressure. When a constant pressure is reached, a liquid valve can be opened or, in the conventional design, opens by itself under spring action. Then liquid flows into the container, the gas escaping from the container flowing through the gas channel. When the liquid surface reaches the lower end of the gas channel, it rises in it. Gas can no longer escape and the filling is stopped.

The advantage of this construction is the large cross-section of the gas channel which is present undisturbed during prestressing and filling. During the prestressing, the gas from the gas space of the boiler reaches the container at high speed so that it is quickly brought into equilibrium with the gas space of the boiler and thus the filling can begin quickly. Even during filling, the return gas flow to the boiler is quick and undisturbed. With this construction, it can be filled very quickly, which is of great economic importance in modern high-performance systems.

The interior of the gas channel is wetted with liquid each time it is filled. During the next filling process, the prestressing of the container entrains the network liquid from the gas channel by the gas flowing in at high pressure. So-called wet pre-air is created. However, since it causes foaming of the beverage, this is harmful and should be avoided.

In the case of filling elements of the known type mentioned at the outset, the gas valve is therefore briefly opened between two filling processes, i.e. when the filling elements are located between the outlet star and the inlet star in a rotating filling device, so that a gas stream flows through the gas channel at high speed and blows out the liquid in it. In this way, dry pre-air is achieved.

A disadvantage of this known construction, however, is that a lot of gas escapes due to the high pressure in the boiler even if the gas valve is opened only briefly. Since the gas above the beverage in the boiler consists essentially of CO₂, a lot of expensive CO₂ is blown off, which entails cost disadvantages. In addition, the liquid blown out of the gas channel is due to the high Gas flow velocity heavily atomized, which leads to liquid deposits on the surrounding machine parts.

A fundamentally different solution to the problem of wet pre-air results with the construction of DE-A-1 216 722. In this construction, a switchable throttle is provided in the gas duct, which is switched on during the entire pre-tensioning process. This ensures that the gas flows through the gas channel at a reduced low speed during the prestressing. This prevents or greatly reduces the entrainment of network liquid from the gas channel into the container. A disadvantage of this construction, however, is that the pretensioning process and thus the entire filling time are considerably lengthened.

The object of the present invention is therefore to create a fast-filling process of the type mentioned, in which the blowing out of the gas channel is associated with lower costs and the atomization is avoided.

This object is achieved with the features of the characterizing part of claim 1.

According to the invention, a throttle is provided in the gas channel, which enables blowing out at a lower gas flow rate. Even with imprecise timing of the blow-out process, the amount of gas blown out can be better controlled due to the lower gas speed, so that there is less gas consumption and thus expensive CO₂ can be saved. Since the gas flow velocity is reduced by the throttle, the liquid that is blown out is atomized less. The throttle is only switched on during blowing out, but during all other operating phases of the filling element switched off. It is therefore switched off in particular during the pretensioning, which can take place with a high cross section of the gas channel, that is to say at high speed, so that the overall filling speed of the filling element remains low or, given a predetermined total filling time, more time is available for quietly filling in the liquid.

The throttled blow-out according to the invention can be carried out in a known manner so that the gas valve opens, blows out and then closes again when the container is changed, ie when there is no container under the filling element. Advantageously with the features of claim 2, the gas valve is only opened and not closed again after blowing out. It remains open until the next container is pressed under the filling element and pre-stressed. This saves a control process. There are no disadvantages due to excessive gas consumption, in contrast to the prior art, in which such a circuit would not be possible because of the unthrottled high gas consumption.

The features of claim 3 are advantageously provided. In this way, a switchable throttle is achieved without additional mechanical effort, in particular without additional control effort. The throttle sits in the form of a throttle piece under the valve body, for which a stroke control is provided anyway. It is only necessary to provide an additional stroke position in which the valve body is open, but the throttle piece is still immersed in the gas channel and throttles it. For pretensioning, the valve body is raised so far into a second stroke position that the throttle piece is lifted out of the gas channel, so that its full cross section is free.

In the drawing, the invention is shown for example and schematically in section through a filling element according to the invention with a gas duct designed as a return air pipe.

As can be seen from the figure, a filling element 2 is connected to the ring bowl 1 of a rotating filling device and extends radially outward. A liquid connection 3 connects the liquid space of the ring bowl with the area above the liquid valve 6 of the filling element and a gas connection 4 the gas space of the boiler with the gas space 5 of the filling element.

Below the liquid valve 6 is the outlet 7 of the filling element, under which a bottle 8 is kept sealed in a known manner.

There is a return air pipe 9 connecting the inside of the bottle to the gas space 5, which is arranged to be vertically movable in the filling element 2 and carries the liquid valve 6. In the usual configuration of such filling elements, the liquid valve is designed to be self-opening. It is supported by a compression spring 11 against the filling element via a flange 10 on the return air pipe 9 and thus opens automatically when equal pressure is established between the interior of the bottle 8 and the gas space 5.

The return air pipe 9 projects with its lower end 12 into the bottle 8 up to the level to which it is to be filled, as is customary in conventional return air pipe designs for known purposes of controlling the filling stop.

At the upper end of the return air pipe, an expanded pipe section 13 is provided, in which a valve body 14 of the gas valve is provided. The valve body 14 has at its upper end two vertically spaced, transverse actuating plates 15 and 16, between which an actuating lever 17 can be brought into engagement, which can be actuated from the outside via a shaft 18 which passes through the housing of the filling element 2. By pressing the operating lever 17 from above onto the lower operating plate 15, the valve body 14 can be moved downwards and by pressing from below against the upper operating plate 16 upwards be moved. The lower actuating plate 15 is further supported in the usual manner downwards against a flange 20 of the return air pipe via a compression spring 19.

On the lower transverse surface of the valve body 14, an annular seal 21 is provided, with which the valve body 14 can come into sealing engagement on the bottom 22 of the expanded tube piece 13, as a result of which the return air tube 9 is closed.

In the case of a filling operation with the filling member which is conventionally constructed in this respect, the actuating lever 17 initially remains force-free. Both the return air pipe 9 and the valve body 14 are in the lower closed position and are held there against the pressure of the compression springs 11 and 19 by the gas pressure in the interior of the filling element. The bottle 8 is now brought under the outlet 7 of the filling element and held in the sealing position. Then, by lifting the actuating lever 17, the valve body 14 is raised and gas flows into the bottle 8 until it has the same pressure (constant pressure) as in the gas space 5. Then, under the action of the compression spring 11, the liquid valve 6 is automatically raised, and Liquid flows into the bottle 8 until it reaches the lower end 12 of the return air pipe 9. As a result, this is closed against gas flowing back into the gas space 5 from the inside of the bottle 8 and the filling is thus stopped. However, liquid rises in the return air pipe 9. The valve body 14 is now moved down into the closed position. Both the liquid valve 6 and the gas valve 21 are then closed, and the bottle 8 can be withdrawn when filled.

If the next filling process follows, there are still wetting drops inside the return air pipe 9 from the previous filling process. During pretensioning, ie when the valve body 14 is raised, gas flows into the bottle under high pressure and entrains these droplets, which atomize finely Place on the inner surface of the bottle 8 and foam the beverage to be filled.

In order to avoid this, according to the prior art, between the filling processes, that is to say when the bottle 8 is removed, the valve body 14 is raised briefly by corresponding actuation of the actuating lever 17. Gas from the gas space 5 flows under high pressure, that is to say at high speed, through the return air pipe 9 into the open and blows out all attached liquid droplets. In the subsequent filling process, dry pre-air can be used. But a lot of gas is lost, especially expensive CO₂.

To remedy this, the invention provides for a throttle to be provided in the gas channel, which throttles the outflow speed. In the embodiment shown in the figure, a throttle piece 24 is arranged below the valve body 14 for this purpose, which is seated concentrically in the return air pipe 9 with a narrow gap 25. The control device controlling the actuating lever 17 is designed such that it only slightly raises the valve body 14 when it is blown out between the filling processes, so that the throttle piece 24 remains in the return air pipe 9 over its essential length, the gap 25 having a strongly restricting effect. Now the gas outflow can be limited by suitable time control so that with sufficient blowing out of liquid droplets only a small gas consumption occurs from the return air pipe 9.

Since, in this stroke position of the valve body 14, the throttle would also work during the pretensioning, as a result of which the pretensioning time is lengthened unfavorably, the valve body 14 is preferably raised over a substantially larger stroke during the pretensioning, to the position shown in dashed lines. The throttle piece 24 is completely lifted out of the return air pipe, so that it is available with a full cross section for rapid pretensioning.

With the construction according to the invention for blowing out, the gas valve 14 can be opened and closed again after a certain time, the advantages of the invention already being obtained. A further design and in particular control simplification can be achieved in that for blowing out the gas valve 14 is only opened and then left in the open position. Then it is blown out - the gas losses can be controlled by the throttling according to the invention - until the next bottle 8 is placed under the filling element. The bottle is then immediately pretensioned when the gas valve is opened further. Then, as previously described, the valve body 14 is advantageously raised into the upper stroke position in order to be able to pretension with a full cross section.

In the context of the present invention, the filling element can be largely varied compared to the illustrated embodiment.

So it can differ from the construction shown the vertical movement of the return air pipe 9 and the liquid valve 6 can be provided separately. Instead of the height-controlled return air tube 9 shown, a gas channel can also be provided, which does not run through the center of the liquid valve 6, but is arranged, for example, outside the filling element.

Instead of filling bottles as shown, the filling element according to the invention can also be varied in a known manner for filling cans.

The design of the throttle can also be solved differently than with the throttle gap 25 shown. The switchability of the throttle can also be solved in a different way, for example by means of valves which switch a throttle bypass line or the like.

Claims (3)

1. Filling head of an apparatus for filling containers with beverages under counterpressure with a gas passage which connects the container at the height of the filling level to the gas space of the tank and has a gas valve, control devices being provided for the gas valve which open it before the beginning of the filling process to pre-pressurise the container, close after the termination of filling and open between the filling processes when no container is present to blow out the gas passage, characterised in that a throttle (24) is provided in the gas passage (9) whereby the control device (15,16,17) is so constructed that the throttle is operative during the blowing out process and is inoperative during the other operational phases of the filling head.
2. Filling head as claimed in claim 1, characterised in that the control device (15,16,17) is so constructed that the gas valve (14) remains open after the blowing out process.
3. Filling head as claimed in claim 1 with a gas valve constructed as a valve body which seals the gas passage and is vertically controlled in the direction of the passage, characterised in that the throttle is constructed as a throttle member (24) which is secured to the valve body (14) and extends into the gas passage (9) and constricts its cross-section, whereby the valve body is controllable into two vertical positions in which, when the valve is open, the throttle member extends into the gas passage and is lifted out of it, respectively.

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