U.S. patent application number 11/890847 was filed with the patent office on 2008-02-14 for apparatus and method for filling syringe barrels.
This patent application is currently assigned to DOPAG Dosiertechnik und Pneumatik AG. Invention is credited to Marc Lang, Urs Luthi, Peter Suter.
Application Number | 20080035233 11/890847 |
Document ID | / |
Family ID | 39049425 |
Filed Date | 2008-02-14 |
United States Patent
Application |
20080035233 |
Kind Code |
A1 |
Luthi; Urs ; et al. |
February 14, 2008 |
Apparatus and method for filling syringe barrels
Abstract
Apparatus for filling syringe barrels (1) with a product (A, B),
includes at least one vacuum unit, at least one filling device, and
a metering head (10) which can be moved with respect to the syringe
barrel (1). The metering head (10) has a first material inlet valve
(11a) and a second material inlet valve (11b) as well as a first
vacuum valve (20a) and a second vacuum valve (20b). The material
inlet valves (11a, 11b) and the vacuum valves (20a, 20b) are
connected to channels (25a, 25b), to each of which a chamber (2a,
2b) of the syringe barrels (1) can be connected, as a result of
which the syringe barrel (1) can be filled through the same
openings (5a, 5b) as those through which the product (A, B) can be
forced out of the chambers (2a, 2b) by pistons (3) for use of the
product, where the pistons (3) are inserted into the syringe
barrels (1) before the barrels are filled.
Inventors: |
Luthi; Urs; (Steinhausen,
CH) ; Lang; Marc; (Luzern, CH) ; Suter;
Peter; (Hagendorn, CH) |
Correspondence
Address: |
COHEN, PONTANI, LIEBERMAN & PAVANE
551 FIFTH AVENUE, SUITE 1210
NEW YORK
NY
10176
US
|
Assignee: |
DOPAG Dosiertechnik und Pneumatik
AG
Cham
CH
|
Family ID: |
39049425 |
Appl. No.: |
11/890847 |
Filed: |
August 8, 2007 |
Current U.S.
Class: |
141/7 ; 141/286;
141/5; 141/65; 141/8 |
Current CPC
Class: |
B65B 3/003 20130101 |
Class at
Publication: |
141/7 ; 141/286;
141/5; 141/65; 141/8 |
International
Class: |
B65B 31/00 20060101
B65B031/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 9, 2006 |
CH |
1288/06 |
Claims
1. Apparatus for filling first and second syringe barrels having
respective first and second pistons which are inserted into the
barrels prior to filling, and respective first and second openings
through which the barrels are filled with product and through which
product is discharged, the apparatus comprising a metering head,
the metering head comprising: first and second channels which can
be connected to respective said first and second openings; first
and second material inlet valves connected to respective said first
and second channels for filling respective barrels with first and
second products; and first and second vacuum valves connected to
respective said first and second channels between said material
inlet valves and said openings of said barrel.
2. The apparatus of claim 1 further comprising means for actuating
the material inlet valves and the vacuum valves pneumatically.
3. The apparatus of claim 2 further comprising first and second
plungers which operate first and second proximity switches in
response to movement of said pistons, said switches being effective
to close the inlet valves when the barrels are filled.
4. The apparatus of claim 1 further comprising first and second
chambers filled with said first and second products, said chambers
being connected to said channels through said inlet valves.
5. The apparatus of claim 1 further comprising first and second
vacuum vessels connected to said channels through said vacuum
valves.
6. A method for filling first and second syringe barrels having
respective first and second pistons which are inserted into said
barrels prior to filling, and respective first and second openings
through which the barrels are filled with product and through which
product is discharged, the method comprising: providing a metering
head having first and second channels, first and second material
inlet valves connected to respective said first and second
channels, and first and second vacuum valves connected to
respective said first and second channels; connecting said first
and second channels to respective said first and second openings;
drawing a predetermined vacuum in said channels via said first and
second vacuum valves so that said pistons are drawn into respective
said first and second barrels; closing said vacuum valves after a
predetermined time; opening said material inlet valves; filling
said barrels with product from first and second supply tanks via
said first and second inlet valves so that said pistons are
displaced in said barrels; detecting the positions of the pistons
by means of plungers which operate respective first and second
proximity switches; and closing the material inlet valves in
response to signals from the proximity switches.
7. The method of claim 6 further comprising: opening the vacuum
valves in order to reduce pressure in the barrels after the
material inlet valves are closed; and closing the vacuum
valves.
8. The method of claim 7 further comprising: disconnecting the
channels from the syringe barrels; and opening the vacuum valves.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention pertains to an apparatus for filling syringe
barrels including a vacuum unit, a filling device, and a metering
head which can be moved relative to the barrel. The invention also
relates to a method for filling the barrel using the apparatus.
[0003] 2. Description of the Related Art
[0004] Apparatus and methods of this type are suitable for filling
syringe barrels with, for example, high-viscosity products.
[0005] An apparatus and a method of this type are known from DE 43
20 098 A1. Pharmaceutical or other products, especially those of
high viscosity, are introduced into the syringe barrel under the
application of a vacuum. Then a piston, which can be used later to
force the product out, is inserted into the barrel. The insertion
of the piston is also carried out under vacuum. How exactly this is
done, however, remains unclear; that is, it is not explained how,
within the scope of series production, the individual pistons are
brought into position and how they are inserted into the syringe
barrels.
[0006] When the piston is inserted into a syringe barrel which has
just been filled with product, it is obvious that some of the
product must be displaced from the barrel again. What happens to
this displaced product and how contamination-free handling is
possible cannot be derived from the document. Nor can it be seen
how the piston is introduced into the syringe barrel.
SUMMARY OF THE INVENTION
[0007] The invention is based on the task of simplifying the
process of filling syringe barrels.
[0008] The apparatus according to the invention is used for filling
first and second syringe barrels having respective first and second
pistons which are inserted into the barrels prior to filling, and
respective first and second openings through which the barrels are
filled with product and through which product is discharged. The
apparatus includes a metering head having first and second channels
which can be connected to respective first and second openings;
first and second material inlet valves connected to respective
first and second channels for filling respective barrels with first
and second products; and first and second vacuum valves connected
to respective first and second channels between said material inlet
valves and the barrel openings.
[0009] In use, the first and second channels are connected to
respective first and second openings, and a vacuum is drawn in the
channels via the first and second vacuum valves so that the pistons
are drawn into the barrels. The vacuum valves are then closed, and
the material inlet valves are opened to fill the barrels with
product from first and second supply tanks via the first and second
inlet valves so that the pistons are displaced in the barrels. The
positions of the pistons are detected by means of plungers which
operate respective first and second proximity switches, and the
material inlet valves are closed in response to signals from the
proximity switches.
[0010] The various features of novelty which characterize the
invention are pointed out with particularity in the claims annexed
to and forming a part of the disclosure. For a better understanding
of the invention, its operating advantages, and specific objects
attained by its use, reference should be had to the drawing and
descriptive matter in which there are illustrated and described
preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows a diagram of a filling apparatus; and
[0012] FIGS. 2a-2c show details of a syringe barrel in the various
phases of a filling operation.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
[0013] FIG. 1 shows a syringe barrel 1, which has a first chamber
2a and a second chamber 2b. The chambers 2a and 2b are then filled
with the products. In the exemplary embodiment, two chambers 2a and
2b are present because the syringe barrel 1 is intended to hold two
different products, which are to be mixed together later for use.
The products can be, for example, the two components of a
two-component adhesive. The first component, therefore, is filled
into the first chamber 2a, and the second component is filled into
the second chamber 2b. A piston 3 is inserted into each of these
two chambers 2a, 2b. By means of seals 4, the pistons close off the
chambers 2a, 2b in leakproof fashion. Each seal 4 is illustrated
schematically as an O ring. Normally, however, double-lip seals are
used in syringe barrels of this type. The chambers 2a, 2b can be
filled through openings 5a and 5b, through which the product can
also be forced out of the chambers 2a, 2b by the pistons 3 for use.
According to the invention, therefore, the pistons 3 are inserted
even before the barrels are filled, which means that the delicate
operation of inserting the pistons 3 into the syringe barrels 1
after they have been filled is eliminated.
[0014] Thus, according to the invention, the syringe barrel 1 is
filled from the same end as that from which it will be emptied
later during use. Thus, for the filling operation, there is no need
for sealing parts such as a caps or plugs to seal tightly the
opening opposite the filling end during the filling process
described in DE 43 20 098 A1.
[0015] For the purpose of filling, the syringe barrel 1 can be
placed on a metering head 10. This metering head 10 contains a
first material inlet valve 11a and a second material inlet valve
11b. These two material inlet valves 11a, 11b can be actuated
pneumatically, for example. From the material inlet valves 11a,
11b, product lines 12a, 12a lead to pressure vessels 13a, 13b, in
which supply tanks 14a, 14b are provided. Products A and B, that
is, the two components to be filled into the barrels, are held in
these two supply tanks 14a, 14b. A pressure-regulated system of
compressed air 15a, 15b is provided for each of the two pressure
vessels 13a, 13b.
[0016] The metering head 10 also contains a first vacuum valve 20a
and a second vacuum valve 20b. These vacuum valves 20a, 20b can
also be actuated pneumatically, for example. From each of the
vacuum valves 20a, 20b, a suction line 21a, 21b leads to a vacuum
vessel 22a, 22b. A vacuum pump 23a, 23b is connected to each of the
vacuum vessels 22a, 22b. A single vacuum pump 23 could also be used
instead of the two vacuum pumps 23a, 23b.
[0017] The second connections of the material inlet valves 11a, 11b
and of the vacuum valves 20a, 20b are connected to channels 25a,
25b. A first channel 25a connects the material inlet valve 11a and
the vacuum valve 20a to the chamber 2a of the syringe barrel 1, and
a second channel 25b connects the material inlet valve 11b and the
vacuum valve 20b to the chamber 2b of the syringe barrel 1. In
terms of its construction, the device is advantageously designed so
that the volume of the channels 25a, 25b is as small as
possible.
[0018] It is advantageous to assign an adjustable plunger 30 to
each piston 3 of the syringe barrel 1; each plunger cooperates with
a proximity switch 31 (only one plunger and only one switch are
shown). The function of these switches will be described further
below.
[0019] Not shown is a holder for the syringe barrel 1, into which
the barrel can be inserted. Not shown either is a transport device,
by means of which the metering head 10 can be moved with respect to
the syringe barrel 1 and thus lowered onto the syringe barrel 1. As
a result, it is ensured through pneumatic control, for example,
that the openings 5a, 5b of the syringe barrel 1 will be aligned
precisely with the channels 25a, 25b. In terms of design, the man
of the art in question is familiar with appropriate possibilities.
For safety reasons, the entire device can be designed for
two-handed control.
[0020] The device shown in FIG. 1 is operated as follows:
[0021] After a syringe barrel 1 has been positioned correctly under
the metering head 10, the two vacuum valves 20a, 20b are opened, so
that a vacuum of predetermined strength is created in the chambers
2a, 2b and in the channels 25a, 25b. A pressure difference thus
acts on the pistons 3, so that the pistons are pushed into their
uppermost position, unless they are already there to begin with.
After a predetermined period of time such as 1 second, the two
vacuum valves 20a, 20b are closed, and immediately thereafter the
two material inlet valves 11a, 11b are opened. Because the pressure
vessels 13a, 13b, in which the supply tanks 14a, 14b are held, are
under a pressure of, for example, 2-6 bars, the two products A, B
are simultaneously forced from the supply tanks 14a, 14b through
the product lines 12a, 12b and the material inlet valves 11a, 11b
into the channels 25a, 25b and onward into the chambers 2a, 2b. The
pistons 3 are automatically displaced. Each piston 3 then strikes
the plunger 30 assigned to it and moves it outward. With the help
of the associated proximity switches 31, the material inlet valves
11a, 11b are closed independently of each other, either
simultaneously or in succession. The two chambers 2a, 2b have now
been filled with products A and B. The chambers 2a, 2b, however,
are still at this point under the pressure which prevails in the
pressure vessels 13a, 13b.
[0022] To prevent the products A, B from escaping and contaminating
the area when the connection between the syringe barrel 1 and the
metering head 10 is broken, the two vacuum valves 20a, 20b are
opened briefly to reduce the pressure.
[0023] Then the metering head 10 is moved a short distance away
from the holder carrying the syringe barrel 1. Between the chambers
2a, 2b and the channels 25a, 25b there is now a gap, into which air
can enter. Then the vacuum valves 20a, 20b are opened again
briefly. As a result, excess amounts of products A, B are suctioned
out of the openings 5a, 5b. These excess amounts of products A, B
are simultaneously suctioned out of the channels 25a, 25b and
transported through the suction lines 21a, 21b back into the vacuum
vessels 22a, 22b, where they collect at the bottom and in some
circumstances can be used again later.
[0024] FIGS. 2a-2c show details of a syringe barrel 1 in various
phases of the filling operation.
[0025] The syringe barrel 1 is shown in the lower part of all three
figures. On top, i.e., at the end facing the metering head 10 (FIG.
1), the barrel has a neck 32 for each of the openings 5a, 5b (FIG.
1). A nozzle 33, which belongs to the metering head 10, can be
inserted into the tip of this neck 32 (FIG. 1). One of these
nozzles is connected to each of the channels 25a, 25b,
[0026] In FIG. 2a, the nozzle 33 is seated with a sealing action in
the opening of the neck 32. The upward-pointing arrow indicates
that air is being drawn out of the space above the piston 3, which
happens during the previously described step in which a vacuum is
produced by the opening of the vacuum valves 20a, 20b. The piston 3
is drawn up as far as it can go.
[0027] FIG. 2b shows the "filling" phase, i.e., the phase during
which the material inlet valves 11a, 1b are open. Now the product
A, B is forced into the space above the piston 3, which
simultaneously is pushed downward. Here, too, an arrow indicates
the delivery direction. The product A, B is also present in the
nozzle 33, but this is not illustrated in FIG. 2b for reasons of
clarity.
[0028] FIG. 2c shows the last step of the process, in which the
excess product A, B is suctioned off. The nozzle 33 is pulled back
slightly here, so that a gap is formed between the bottom end of
the nozzle 33 and the sealing surface in the interior of the neck
32. During the suction process, again indicated by a straight
arrow, air can enter between the neck 32 and the nozzle 33. The
part of the product A, B located above the bottom edge of the
nozzle 33 is suctioned off. It should therefore be obvious that it
is advantageous for the volume of the spaces between the vacuum
valves 20a, 20b (FIG. 1), the material inlet valves 11a, 11b, and
the bottom edge of the nozzle 33 to be as small as possible,
because then only a small amount of the product A, B will need to
be suctioned off. The suctioning-off step is the last step of the
filling operation for the syringe barrel 1.
[0029] The invention simplifies the filling of syringe barrels
1.
[0030] The invention is not limited by the embodiments described
above, which are presented as examples only, but can be modified in
various ways within the scope of protection defined by the appended
patent claims.
* * * * *