Arrangement for a tapping tube

The invention relates to a tapping tube intended for the filling of container-like receptacles, such as bottles, with a liquid, said tapping tube preferably communicating with a metering pump, whereby the liquid in question is intended to flow through the tapping tube and to be interrupted during removal and replacement of the receptacles in question. An arrangement for a tapping tube of this kind is made available in which above all dribbling and dripping can be prevented, especially in conjunction with the removal and replacement of the receptacles. There is connected to the tapping tube (1) a suction channel (14) which discharges in the vicinity of its lower end and which is so arranged as to be actuated in such a way as to provide a suction effect at least for the duration of the aforementioned interruption in the flow of liquid through the tapping tube.

The present invention relates to an arrangement for a tapping tube intended 
for the filling of container-like receptacles, such as bottles, with a 
liquid, said tapping tube preferably communicating with a metering pump, 
whereby the liquid in question is intended to flow through the tube and to 
be interrupted during removal and replacement of the receptacles in 
question. 
Previously disclosed tapping tubes of the kind referred to above often 
suffer from the disadvantage that dribbling or dripping occur during 
removal and replacement of the receptacles, even if the flow of liquid is 
interrupted during this period. What this means is that liquid is spilled 
outside the receptacle, which poses a particularly serious problem when 
handling environmentally harmful liquids. 
This problem is eliminated with an arrangement in accordance with the 
invention, which is characterized essentially in that there is connected 
to the tapping tube a suction channel which discharges in the vicinity of 
its lower end and which is so arranged as to be actuated in such a way as 
to provide a suction effect at least for the duration of the 
aforementioned interruption in the flow of liquid through the tapping 
tube, for the purpose of preventing dripping or dribbling during removal 
and replacement of the receptacles.

The reference designation 1 is used in FIG. 1 to indicate in its entirety a 
so-called tapping tube, that is to say a tube through which the liquid 
which is to be introduced into a container-like receptacle, such as a 
bottle in the illustrative embodiment shown, is caused to flow, preferably 
under the control of a metering pump or some other metering arrangement 
which may be of a previously disclosed kind and may be attached to a line 
connected to the upper end of the tapping tube. Since the invention is not 
affected directly by this arrangement, which may, furthermore, be of a 
previously disclosed kind, there is no reason to describe it in more 
detail here. The tapping tube 1 exhibits at the bottom an end seal 
consisting of a body 2, which internally inside the tapping tube exhibits 
an upper cone-shaped part 2a which widens out in the downward sense and 
which exhibits an externally threaded part 2b at the bottom. Screwed 
securely onto the thread of the end sealing body 2 at the bottom is a 
guide cone 3, which tapers in a downward sense from an upward-facing 
shoulder 4 which forms the base for a sealing ring 5 of the `O`-ring type. 
The upward-facing end surface of the guide cone 3 is sealed against a 
downward-facing shoulder on the end sealing body by means of a further 
sealing ring 6 of the `O`-ring type. The cone 2a of the end sealing body 
is terminated at the bottom by a cylindrical part 2c before the flange 2d, 
which forms the shoulder against which the sealing ring 6 makes contact. 
The cylindrical part 2c has a diameter which corresponds to the internal 
diameter of the tapping tube 1, in which case the end sealing body with 
the cylindrical part 2c is pressed or screwed into the tapping tube 1. The 
tapping tube exhibits wall openings 7 distributed around its periphery 
adjacent to the end sealing body. The reference designation 8 is used to 
identify a sliding sleeve surrounding the lower part of the tapping tube, 
which internally exhibits a slightly larger diameter than that of the 
tapping tube, so as to form an annular space 9 between the tapping tube 
and the inner wall of the sliding sleeve, which is terminated at the top 
by a bearing sleeve 10 pressed into or in some other way attached to the 
sliding sleeve. Positioned in a recess in the upper end part of the 
sliding sleeve is a sealing ring 11 which forms a seal between the sliding 
sleeve and the tapping tube 1. Held in position against the upper end of 
the sliding sleeve by means of a thrust washer 12 is the lower end of a 
compression spring 13 of the helical type, the upper end of which is in 
contact with a stop situated towards the top of the tapping tube 1, such 
as an end part 14a of a suction tube 14 projecting through the tapping 
tube, extending down through the tapping tube centrally inside it, and 
passing through a central hole in both the end sealing body 2 and the 
guide cone 3, at the lower end of which said suction tube emerges. The 
compression spring 13 endeavours to hold the sliding sleeve 8 with its 
lower end edge in contact with the upper shoulder 4 of the guide cone via 
the sealing ring 5. Beneath the bearing sleeve 10 the wall of the sliding 
sleeve 8 is penetrated by a pipe stub 15, which forms a communication 
between the annular space 9 and, for example, a collection vessel for 
foam, excess liquid or similar. The outlet stub for the suction line 
should preferably be connected to a suction pump, which may be of a 
previously disclosed kind, preferably being a suction pump so arranged as 
to operate intermittently, that is to say with an interruption during the 
filling operation, but which is in operation during the period of removal 
and replacement of the receptacles to be filled. 
The function of the arrangement is described below in conjunction with the 
filling of bottles with a comparatively narrow neck, that is to say a neck 
which is only slightly larger than the external diameter of the lower end 
part of the sliding sleeve 8 which is transformed into a downward-facing 
stop 16, adjacent to which a sealing ring 17 of the `O`-ring type is 
positioned. 
It is assumed that a bottle has been filled, that the tapping tube has been 
raised by a sufficient amount for the guide cone 3 to be situated above 
the neck opening of the bottles in question, and that a new bottle has 
been moved into position either with the help of an appropriate feeding 
arrangement or manually. The suction tube 14 will now be under negative 
pressure via the outlet stub 14a produced by a suction pump of an 
appropriate kind. Any liquid remaining from the previous filling operation 
will be sucked away through the suction tube, thus preventing dribbling or 
drips from falling from the lower end of the guide cone 3 during removal 
and replacement of the receptacles. Once a new bottle 18 has been 
positioned beneath the tapping tube, the entire unit is lowered down into 
the bottle and into the position shown in FIG. 2. At the start of the 
downward movement the outer conical surface of the guide cone 3 will help 
to ensure effective guidance into the neck opening of the bottle. Once the 
upper edge of the neck 18a of the bottle has come into contact with the 
downward-facing stop 16 on the sliding sleeve via the sealing ring 17, the 
sliding sleeve will be retained in this contact position against the 
effect of the bias of the compression spring 13, whilst the tapping tube 
will continue its downward movement into the bottle, preferably as far as 
the position shown in FIG. 2. This continued movement will cause the 
contact between the lower end edge of the sliding sleeve 8 and the 
upward-facing shoulder of the guide cone 3 to cease, and the inside of the 
tapping tube will thus come into open communication with the internal 
space of the bottle 18. Once the tapping tube has reached its position 
introduced down inside the bottle, the metering arrangement, which may be 
a piston pump, for example, which communicates with the tapping tube will 
be set in operation, which means that the liquid with which the bottle is 
to be filled will flow down in the direction of the arrows 19 inside the 
tapping tube and out into the bottle. The flow of liquid is deflected 
gently at the bottom before it exits into the bottle thanks to the conical 
upper surface 2a of the end sealing body 2, and thanks to the fact that 
the discharge openings 7 are arranged immediately adjacent to the conical 
surface. Foaming in conjunction with discharging of the liquid is reduced 
to a minimum in this way. Because the contact between the sliding sleeve 8 
and the upper edge of the guide cone 3 has ceased, the inside of the 
bottle 18 is now also connected via the outlet stub 15 with a collecting 
vessel for receiving any excess liquid and possibly foam which has formed 
inside the bottle. The aforementioned metering equipment shall preferably 
be adjusted in such a way that the desired level of filling is achieved in 
the bottle. Over-filling will thus occur only in the event of a fault 
arising in the metering equipment. The outlet stub 15 also serves as the 
exit route for any gases which may have formed inside the bottle, which 
can be dealt with in an environmentally harmless fashion for the 
surroundings and for the staff working in the filling plant. Once the 
metering arrangement has pumped the appropriate quantity through the 
tapping tube 19, the arrangement is raised and the sliding sleeve 8 will 
again come into contact with the guide cone and will thus interrupt the 
passageway not only between the inside of the tapping tube and the 
surroundings, but also between the inside of the bottle or the 
surroundings and the pipe stub 15. 
The invention is not restricted to the above design, which is described 
only as an example, but may be modified in respect of its detail features 
within the scope of the following Patent Claims without departing from the 
fundamental idea of invention. The metering arrangement may thus be of any 
appropriate kind. It need not, therefore, be a piston pump, as stated in 
the specification. The metering arrangement need not be a pump at all. The 
tapping tube need not be be so arranged as to execute a reciprocating 
upwards and downwards movement, but filling could take place with the 
tapping tube stationary at a point above the neck of the bottle or the 
opening to the recipient in question, which may naturally also be a vessel 
which does not resemble a bottle, such as a vessel with a large opening.