EP1266862A1 - Filling head for container filling machines - Google Patents

Abstract

An outlet (2) for the product is closed by a valve (3) with valve seating (4) and a movable valve body (5). A setting piece (6) is in contact with the valve body. The closing movement of the valve body is slowed down at least in the end phase by a damping arrangement (7) at least before reaching the valve seating. The setting piece is in the form of a single acting pneumatic cylinder with piston rod (21).

Description

The invention relates to a filling element for Container filling machines according to the preamble of claim 1.

Such filling elements are used, among other things, for filling Beverage bottles are used and come in different Designs known. The valve body is doubled acting pneumatic cylinders, single acting Pneumatic cylinder in connection with energy accumulators, Actuated electromagnets or the like, the z. B. by Flow meter in the product feed line or through Level probes in the containers or in dosing chambers to be controlled. In particular, the closing stroke of the Valve body is running at high speed the uncontrolled wake between the onset of Closing movement and the final locking of the product to keep as low as possible. With single-acting Pneumatic cylinders are affected by the high closing speed achieved a correspondingly high pressurization, the also the reliable guard locking contrary to that of Lift mechanism generated opening force is used.

However, the quick closing of the product valve leads often that at the end of the closing process from the Product spills leak uncontrolled splashes. This can contaminate the container or the filling machine Reduce filling accuracy and undesirable foaming of the product in the container.

The invention has for its object in a filler an uncontrolled splashing of the type mentioned at the beginning of the product at the end of the filling process with simple Prevent funds.

This object is achieved by the in the license plate of the specified features solved.

In a filling element according to the invention, the approximation of the Valve body to the valve seat initially with the for reasons the filling accuracy desired high speed. Only then occurs in the final phase of the closing stroke targeted braking by the damping device. It has has shown that this is sufficient to control the uncontrolled Avoid splashes as much as possible. So it is with one Closing stroke of 5 to 6 millimeters, as in Bottle filling machines are often present, sufficient Closing movement increases by approx. 50% in the last 2 millimeters reduce. Hits at this reduced speed then the valve body onto the valve seat. This also leads to reduced mechanical stress on the Filling device. Also a gradual reduction in Closing speed, possibly over the entire closing stroke, brings good results.

The damping device can consist of separate, customary Damping elements such as oil filled shock absorbers with Spring return can be built up. Because of the short stroke and the low forces are the ones to be used for this Low cost. Such damping elements can also retrospectively on existing container filling machines be retrofitted.

It when the damping device is particularly advantageous is integrated in the actuator, e.g. in form of a End position damping in a pneumatic cylinder. this leads to a closed, hygienic and reliable Construction. In any case it is important that the Damping device an exact, reproducible Exerts braking effect during the closing process keep the resulting wake constant.

Advantageous further developments in this regard are the dependent claims refer to.

Fig. 1

den senkrechten Schnitt durch ein Füllorgan mit separater Dämpfungseinrichtung

Fig. 2

den senkrechten Schnitt durch ein abgewandeltes Stellorgan des Füllorgans nach Fig. 1 mit integrierter Dämpfungseinrichtung bei Beginn des Schließhubs

Fig. 3

das Stellorgan nach Fig. 2 am Ende des Schließhubs.

Two exemplary embodiments of the invention are explained below with reference to the drawings. Show it:

Fig. 1

the vertical section through a filling element with a separate damping device

Fig. 2

the vertical section through a modified actuator of the filling element according to FIG. 1 with integrated damping device at the beginning of the closing stroke

Fig. 3

2 at the end of the closing stroke.

The filling element 1 according to FIG. 1 is for filling bottles 27 under atmospheric pressure with a still drink, e.g. water or iced tea. It is together with a number identical filling organs evenly distributed on one annular rotor 8 attached to a vertical The axis of rotation 9 can be driven continuously. The rotor 8 belongs to a bottle filling machine shown only partially, which are also arranged concentrically to the axis of rotation 9, with rotating product container 10 and below the Filling elements 1 arranged lifting elements 11 fastened to the rotor 8 for lifting the bottles 27 to be filled to the filling elements 1 has.

The filling element 1 has a tubular, multi-part housing 12 on that with a lateral approach on the rotor 8th rests and is fastened there by means of screws. Internally the housing 12 is a vertical one, substantially rotationally symmetrical product channel 13 formed on the formed a tapered valve seat 4 at the lower end is. This is followed by a tubular outlet 2 for the product that has several openings in the lower forehead area 14, from which the product into the by the lifting member 11 raised above the outlet 2, but no contact with the Filling element 1 having bottle 27 runs in.

In the valve chamber 13 is a valve body 5, which is on tapered lower end, supported for vertical movement. The Valve body 5 is on a tubular valve lifter 15 attached, upwards out of the valve housing 12 led out and by means of an inside of the product channel 13 arranged flexible bellows 15 gas and liquid tight is sealed. Furthermore, in the valve body 5 is a down Outstanding return gas pipe 17 attached to the Bore of the valve lifter 15 opens out. Besides, that is Return gas pipe 17 in the lower end region of the outlet 2 flexibly guided. It sticks out with the lower one, with the Areas 14 provided area of the outlet 2 in the mouth the bottle 27 to be filled in and performs this during the filling from the bottle 27 displaced gas over the Valve tappet 15 and one outside the valve chamber 12 this connected return gas line 18 back into the Product container 10.

The valve seat 4 and the vertically movable valve body 5 together form a valve 3 for controlling the in the bottle 27 incoming product stream. In Fig. 1, this valve is 3rd shown in its open position. This is through realized an energy store in the form of a compression spring 19, the between the top of the housing 12 and an am protruding upper end of the valve lifter 15 attached connector 20 is inserted.

The valve 3 is closed by an actuator 6a in Realized in the form of a single-acting pneumatic cylinder, who is exposed to compressed air through his Piston rod 21, the connector 20 acting as a stop and the valve lifter 15 moves the valve body 5 downward, until it strikes the valve seat 4. The Pneumatic cylinder 6a is powered by an electropneumatic Controlled control device 22 to which a flow meter 23 is connected. This is in the product line 24 turned on, which the product container 10 with the upper End of the product channel 13 connects.

The rigidly attached to the upper end of the valve lifter 15 Connector 20 has a side to the axis of rotation 9 pointing approach 25 with a horizontal bottom Contact surface. Below this is at the top of the Housing 12 attached a damping device 7a. This includes a cylinder filled with oil, both of which Cylinder chambers via an adjustable throttle and a Check valve are connected. Through an integrated The piston is compressed into its upper end position pushed, which is shown in Fig. 1. Here lies between the stop surface of the extension 25 and the upper end of the piston rod protruding upwards from the cylinder Damping device 7a a distance "a" of 4 millimeters in front.

The filler 1 described above works as follows: After with continuously rotating rotor 8 and closed product valve 3 by the lifting member 11 a empty bottle 27 in the filling position shown in Fig. 1 has been raised, the controller 22 of the Pneumatic cylinders 6a previously loaded with compressed air vented. The compression spring 19 now lifts over the connector 20 and the valve lifter 15 on the valve body 5, so that Product valve 3 is opened immediately. Now running due to the height difference the product from the Product container 10 via the product line 24, the Product channel 13, the product valve 3 and the outlet 2 and the openings 14 into the bottle 27. Doing so will in the bottle 27 ambient air through the Return gas pipe 17, the hollow valve lifter 15, which pierced Connector 20 and the return gas line 18 in the Product boiler 10 displaced and blown from there into the open.

The flow meter 23 registers the filled Product volume and reports this to the control device 22. As soon as a predetermined volume has been reached, the Control device 22 pressurization of the Pneumatic cylinder 6a. Its piston rod 21 then moves via the connector 20 and the valve lifter 15 den Valve body 5 of the product valve 3 in the downward direction Closed position, against the force of the compression spring 19.

During the first four millimeters according to the distance a of the six millimeter long closing stroke Valve body 5 with the desired high closing speed moved undamped towards valve seat 4. This will make the Overrun minimized during the closing movement. Once the Approach 25 to the extended piston rod Damping device 7a hits the Closing speed slowed down and the last two Millimeters corresponding to the distance b of the closing stroke run braked, approximately at 50% of the original or Early closing speed. With this braked The valve body 5 then meets the speed Valve seat 4 on. Here, the oil flows in the Damping device 7a from the lower cylinder chamber the throttle in the upper cylinder chamber.

The blow when the valve body 5 strikes the Valve seat 4 is so much defused and the components of the Filling device 1 are spared. It also makes the Acceleration or displacement effect during the Closing movement in the areas entering the product channel 13 the valve lifter 15 and the expanding bellows 15 on the one hand and the narrowing of the cross section between Valve body 5 and valve seat 4 on the other hand so far mitigates that none at the openings 14 Bottle filling machine or bottle 27 polluting or product splashes that impair the filling result can.

If during the subsequent filling process the liquid valve 3 opened again by venting the pneumatic cylinder 6a, see above is the piston of the damping device 7a by the Pressure spring quickly back to its upper starting position procedure, taking the oil out of the upper cylinder chamber the check valve flows into the lower cylinder chamber.

2 and 3 is the Damping device 7b in turn as a pneumatic cylinder 6b trained actuator of the otherwise unchanged Filling device 1 integrated. For this purpose, the one with the Connector 20 cooperating piston rod 21 under the actual working piston 26 a damping piston 28 attached. Between the working piston 26 and the Damping piston 28 is an annular chamber 29 which via a first bore 30 in the cylinder wall with the Atmosphere. Via a second bore 31 in the Piston rod 21 is the annular chamber 29 with one in the Piston rod 21 formed control chamber 32 connected. In this is a control slide 33 movably mounted by a compression spring 34 in its upper shown in Fig. 2 End position is pushed.

In the spool 33 and in the control chamber 32 and in the Piston rod 21 control channels 35 are formed, which at the upper position of the control slide shown in Fig. 2 33 the working space formed above the working piston 26 with the one formed under the damping piston 28 Connect the damping space. The latter is above one Throttle bore 37 in connection with the environment. Moreover is over the upper end of the spool 33 elastic sleeve 36 arranged, the sealing lips Release the flow of compressed air from top to bottom and prevent from bottom to top.

The control slide 33 takes under the influence of the compression spring 34 its defined by stops in the piston rod 21 upper end position (Fig. 2), connect the control channels 35 the working chamber formed above the working piston 26 38 with the one formed under the damping piston 28 Damping chamber 39. This is through the throttle bore 37 permanently connected to the environment. On the other hand, he takes Control spool 33 under the influence of in the working chamber 38 prevailing overpressure its lower end position (Fig. 3) so the cuff 36 lies at the mouth of the Control channel 35 sealingly into the working chamber 38, whereby the connection between working chamber 38 and Damping chamber 39 is interrupted.

The control slide 33 and the compression spring 34 are in the the present case is such that, starting from from the position in Figure 2, when supplying compressed air from 6 bar into the working chamber 38 via a connecting line 40 the control channels 35 remain open until just a pressure of 3 bar is built up in the damping chamber 39 Has. Here, the control slide 33 moves relative to Piston rod 21 in its lower end position according to FIG. 3, while the piston rod 21 with the working piston 26 and the Damping piston 28 does not yet move significantly.

Now the piston rod 21 is due to the full on the Working piston 26 acting pressure of 6 bar quickly after moved down. This builds up in the damping chamber 39 the air cushion trapped there is getting stronger opposing force that reaches its maximum when the piston rod 21 of its lower end position according to FIG. 3 approaches. The impact of the valve body 5 on the Valve seat 4 is thereby optimally damped.

During the closing movement, the starts immediately Ventilation of the damping chamber 39 via the throttle bore 37, so that also by the size of the throttle bore Damping force can be adjusted. The venting of the Damping chamber 39 is when the lower end position is reached the piston rod 21 according to FIG. 3 has not yet been completed but continues for a short time until in the Damping chamber 39 the normal air pressure prevails. this has the advantage that the full closing force corresponds to the Working pressure of 6 bar on the piston rod 21 and thus on acts the valve body 5. The tumbler of the valve 3 is thus in no way by the damping device 6b with special needs.

Claims (10)

Filling element (1) for container filling machines with an outlet (2) for the product, which can be closed by a valve (3) with a valve seat (4) and a movable valve body (5), an actuator (6) acting on the valve body, thereby characterized in that the closing movement of the valve body (5) is slowed down at least in the final phase by a damping device (7). Filling element according to claim 1, characterized in that the closing movement of the valve body (5) is braked by the damping device (7) at least shortly before it hits the valve seat (4). Filling element according to claim 1 or 2, characterized in that the closing movement of the valve body (5) in the final phase of the closing movement is slowed by approximately 50% compared to the initial phase. Filling element according to one of claims 1 to 3, characterized in that the closing movement of the valve body (5) is slowed down approximately during the last third of the closing stroke. Filling element according to one of claims 1 to 3, characterized in that the closing movement of the valve body (5) is slowed down substantially, preferably progressively, during the entire closing stroke. Filling element according to one of claims 1 to 5, characterized in that the damping device (7a) is formed by its own component and is arranged outside the actuator (6a). Filling element according to one of claims 1 to 5, characterized in that the damping device (7b) is integrated in the actuator (6b). Filling element according to claim 7, characterized in that the adjusting element (6b) is designed as a single-acting pneumatic cylinder, on the piston rod (21) of which, in addition to the working piston (26) interacting with a working chamber (38), a damping piston (interacting with a damping chamber (39)) 28) is arranged, and the damping chamber (39) is connected to the atmosphere via a throttle (37). Filling element according to claim 8, characterized in that in the piston rod (21) the working chamber (38) with the damping chamber (39) connecting control channels (35) are formed, which with a movably arranged in the piston rod (21) control slide (33) and interact with a seal (36) in such a way that the working chamber (38) and the damping chamber (39) can be briefly connected to one another at the beginning of the closing stroke. Filling element according to claim 9, characterized in that an annular space (29) permanently connected to the atmosphere is formed between the working piston (26) and the damping piston (28).

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