Dispenser for paste-like products

A dispenser for paste-like products comprises a headpiece including a discharge channel with a dispensing orifice, and a pump chamber the volume of which changes with the application of an external load and which is connected by a communication path, sealed by a check valve which can only open in the direction of the dispensing orifice, to said discharge channel, and said headpiece is connected to a container, the end of the container away from the headpiece being provided with an opening inside which is located a piston sliding in sealing engagement along the container interior wall, said connection between the headpiece and the container possibly being detachable. The interior of the container communicates with the pump chamber by a check valve, which can only open in the direction of the pumping chamber and which is mounted in a support base extending between the pump chamber and the container interior. The check valve between the pump chamber and the container includes a valve seat in the form of a conical element tapering toward the pump chamber and connected by bridges to the support base and surrounded by a number of passageways between the bridges. Furthermore, the check valve includes as its closure member a flexible apertured disk mounted coaxially with the conical element and held at its radial outer area on the support base while in the closed position it rests in sealing engagement of its inner rim with the surface of the conical element whereby it covers the passageways.

The invention concerns a dispenser for paste-like products provided with a 
headpiece including a discharge channel with a dispensing orifice and with 
a pump chamber, the volume of which is varied by means of external load, 
said pump chamber being connected by an outlet communicating path to said 
discharge channel which can be sealed by an outlet check valve which can 
be opened only in the direction of the dispensing orifice, and further 
provided with a container connected to said headpiece, the end of the 
container which is remote from the headpiece comprising an orifice and the 
container being internally equipped with a slidable piston moving in 
sealing engagement along the container interior wall, the interior of the 
container being connected to the pump chamber by means of an inlet check 
valve which can open only in the direction of the pump chamber and which 
is mounted in a support base extending between the pump chamber and the 
interior of the container. 
It is possible using dispensers of the above discussed kind to dispense 
paste-like materials by means of a volumetric change of the pump chamber 
induced by an external load, for instance finger pressure applied to an 
actuation knob connected to a pump piston, and to dispense them in rates 
depending on said volumetric changes in the pump chamber. Atmospheric 
pressure is utilized for the purpose of forcing the paste-like mass out of 
the dispenser, this atmospheric pressure acting on the lower side of the 
piston sealing the interior of the end of the container remote from the 
headpiece and which following the generation of a partial vacuum in the 
pump chamber presses an amount of the paste-like mass into the pump 
chamber corresponding to the implemented volumetric change thereof. From 
there this amount will be forced, at the next volume decrease in the pump 
chamber and by means of operating the check-valves provided, through the 
discharge channel and out of the dispensing orific. Accordingly there is 
no need of special propellant means to expel the paste-like substance from 
the dispensers of the kind above discussed. The dispenser can be actuated 
with very modest forces, for instance finger pressure. 
For economic employment of the dispensers of the above discussed kind and 
in particular for their use in packaging paste-like products used in large 
amounts, it is especially important to have the feasibility of 
economically manufacturing containers of the above discussed type in mass 
production. 
It is the object of the invention to create a dispenser of the kind above 
discussed with a design of few parts which are sturdy and easily 
assembled, to be mass-produced economically and assembled efficiently, of 
which the operation is accurate and free from malfunction. 
This problem is solved by the invention in that the inlet check valve is 
provided with a conical element tapering toward the pump chamber and 
acting as the valve seat, which is connected by bridges to the support 
base and which comprises a number of passageways circularly arranged 
around it between the bridges, and in that further an apertured disk made 
of a flexible material is provided and mounted coaxially with the conical 
element, tightly held on the support base at its radial outer area, which 
in the sealed position rests by its inner rim against the surface of the 
conical element and thereby covers the passageways. 
The dispenser of the invention offers substantial advantages over the state 
of the art. The inlet check valve consists of two simple-shaped parts 
which can be manufactured efficiently. One part is the conical valve seat 
connected to the support base and comprising the passageways arranged 
peripherally around the valve seat. This part of the inlet check valve 
illustratively can be produced in great numbers and economically by 
injection molding. The design of the closure member of the inlet check 
valve as an apertured disk made of an elastic material also makes it 
possible to produce it in mass production. Again injection molding is 
applicable, for instance with elastomers. Furthermore when suitably 
shaping the apertured disk mass production by stamping is also possible. 
Due to simple geometry, in particular of the apertured disk, tooling costs 
for the production tools can be kept very low. In the light of the 
geometry of the inlet check valve of the dispenser of the invention, other 
components of this dispenser, in particular the headpiece and the 
container, can be kept to very simple shapes with few undercuts, making 
possible again in this respect very simple manufacturing tools, for 
instance for injection molding, and hence economical production. By the 
cooperation between a conical valve seat and an elastic apertured disk as 
the closure means, a reliable seal is obtained in the closed position. The 
danger of jamming of moving parts is excluded from the design of the 
invention. Accordingly, operation will be reliable. 
Advantageously the dispenser of the invention is so designed that the 
closure member of the outlet check valve is integral with the apertured 
disk of the inlet check valve. In such a design the dispenser of the 
invention is assembled from especially few parts and accordingly 
manufacture and assembly are each particularly simple and economical. 
An especially advantageous geometry of the dispenser of the invention is 
obtained when the closure member of the outlet check valve is a flexible, 
conically flaring annular wall mounted concentrically with the apertured 
disk to which it is joined integrally at its narrower end and, in the 
closed position, externally resting in sealing manner by its free flared 
end against the free rim of an annular collar forming a section of the 
pump chamber wall and terminating at a distance from the support base, the 
said free flared end sealing the periphery of said annular collar and 
thereby closing the communication path between the pump chamber and the 
discharge channel formed by the annular gap between the free rim of the 
annular collar and the apertured disk. In this design, once a vacuum has 
been generated in the pump chamber, the paste-like substance is forced 
first out of the container interior through an annular slit created by the 
vacuum-induced elastic upward flexure of the inner rim of the apertured 
disk around the periphery of the conical valve seat whereby said substance 
passes into the pump chamber. If thereupon the volume of the pump chamber 
is reduced again by external action, then the higher pressure so formed 
closes the inlet check valve whereby the inner rim of the apertured disk 
is forced again downward to come to rest on the conical valve seat. 
Simultaneously the pressure from the substance in the pump chamber 
elastically and uniformly deforms the conical annular wall of the closure 
member of the outlet check valve along its entire periphery in the outward 
direction, so that an annular gap is created between the free rim of the 
annular collar and the conical annular wall, and the said substance is 
forced through said annular gap into a space connected to the discharge 
channel and from this space it is forced out through the dispensing 
orifice. Due to the comparatively large periphery of the resulting annular 
slit, the flexure of the conical annular wall required to achieve an 
adequate cross-sectional passage for the substance to be dispensed is 
minute. As a result the distances between the open and closed positions of 
the closure members are also minute and hence the deformations are minute 
too. This is especially advantageous for the service life and reliability 
of the dispenser of the invention. 
A further advantageous embodiment of the above described dispenser resides 
in that the thickness of the radial inner area of the apertured disk which 
is located radially within the conical annular wall is gradually tapered 
toward the inner rim. As a result the radial inner area of the apertured 
disk is especially flexible and the inner rim seals especially 
advantageously the conical valve seat when the inlet check valve is in the 
closed position, also providing a reliably adequate curvature of the 
radial inner area of the apertured disk toward the pump chamber when the 
inlet check valve is in the open position. 
An alternatively advantageous design of the dispenser of the invention is 
achieved by forming the closure member of the outlet check valve by a 
medial annular area positioned concentrically on the surface of the 
apertured disk facing the pump chamber and at approximately equal radial 
distance from the inner and outer rims of the disk wherein said annular 
area resting in sealing engagement against the free lower rim of an 
annular collar arranged coaxially with the apertured disk and which in the 
closed position forms a section of the pump chamber wall, in this manner 
closes the communication path from the pump chamber to the discharge 
channel extending around said free lower rim of the annular collar. This 
design achieves an especially simple geometry of a simple, flat apertured 
disk forming the integrally joined closure members of the inlet and outlet 
check valves and accordingly also achieves the ensuing advantages in 
manufacture and assembly. In this design the radial inner area of the 
apertured disk in the presence of a vacuum curves upward into the pump 
chamber, that is, when the inlet check valve is in the open position, it 
curves upward and thus provides an annular slit between the inner rim of 
the apertured disk and the surface of the conical valve seat. The moment a 
higher pressure is produced in the pump chamber, the inner rim of the 
apertured disk comes to rest against the surface of the conical valve 
seat. The radial inner area of the apertured disk curves downward under 
the action of higher pressure from above, the radial outer area of the 
apertured disk resting on the support base and the inner rim of the 
apertured disk resting on the surface of the conical valve seat. Because 
the radial inner area of the apertured disk curves downward, an annular 
slit is created between the medial annular area of the disk acting as the 
closure member of the outlet check valve and the free lower rim of the 
annular collar forming a part of the pump chamber wall. The paste-like 
material in the pump chamber then can flow through this annular slit into 
an externally adjoining chamber connected to the discharge channel, 
whereby the substance is externally discharged through the orifice of the 
discharge channel. 
The dispenser of the invention furthermore may assume such a design that 
together with an inlet check valve of the invention comprising a conical 
valve seat and apertured disk as the closure member, use is made of an 
outlet check valve mounted in the communication path between the pump 
chamber and the discharge channel and designed as a separate component. 
Illustratively the outlet check valve may comprise a closure member 
designed as an inset which can be installed in the discharge channel and 
which is equipped with an elastically hinged sealing flap covering the 
communication path in the closed position. 
An especially simple design of the dispenser of the invention is achieved 
when the support base is integrally joined with the container and the 
radial outer area of the apertured disk is clamped and tightly held 
between the support base and a peripheral projection of the headpiece 
fixed to the container. The headpiece for such a design illustratively can 
be connected to the container by a snap fastener or also by means of a 
screw. 
Another advantageous design of the dispenser of the invention is that 
wherein the support base forms part of the headpiece and wherein the 
apertured disk is supported within this headpiece. In this case the 
headpiece is connected detachably, for instance by a screw means to the 
container, and this container can be wholly open at the top. Such 
containers can be manufactured in especially simple manner as exchangeable 
containers and can be marketed also without headpieces. After filling, the 
upper opening of the container can be closed, for instance by sealing with 
a thin foil which is removed prior to connecting the container to the 
headpiece. 
An especially simple design of the dispenser of the invention is provided 
by the pump chamber being sealed at its upper region by an elastically 
deforming cap which curves upward like a dome. Such a cap can be 
mass-produced from elastomeric materials, for instance by 
injection-molding, and it can be mounted in a simple manner to the 
headpiece, for instance by a snap fastener. By deforming the cap, for 
instance by finger pressure from above, large volumetric changes can be 
achieved in the pump chamber and hence correspondingly large discharges 
can be obtained. 
Illustrative embodiments of the invention are described below in relation 
to the drawing.

FIG. 1 is a longitudinal section of a first embodiment of the dispenser. 
The headpiece 1 of this dispenser consists of a plastic, injection-molded 
component 2 provided with a discharge channel 3 and a cap 4 made of an 
elastically yielding plastic, which is connected in snap-in fashion to the 
component 2. The component 2 is connected at its lower end by a snap-in 
means to the upper end of a container 5. This container also is made of an 
injection-molded plastic and assumes a cylindrical shape. The lower end of 
the container 5 is open. A slidable piston 6 is inserted into the 
container in sealing engagement with the interior wall thereof. The piston 
6 also is made of an injection-molded plastic. 
A pump chamber 7 within the headpiece 1 is defined at its sides by the 
walls of the component 2 and at its top by the cap 4. A transverse wall is 
integrally joined to the upper end of the container 5 and forms the 
support base 8. A valve seat for an inlet check valve in the form of a 
conical element 9 tapering toward the pump chamber 7 is mounted in the 
support base 8 coaxially with the central axis of the container and is 
connected by bridges 10 to the pump chamber support base 8. Passageways 
are provided all around the element 9 between the bridges 10 to connect 
the interior of the container 5 with the pump chamber 4. The closure 
member of the inlet check valve is an apertured disk 11 made of a highly 
flexible plastic and arranged coaxially with the element 9. The apertured 
disk 11 rests by its radial outer area and lower surface on its entire 
periphery or outer rim on the support base 8. An annular peripheral 
projection 12 extends downward from component 2 of headpiece 1 toward the 
radial outer area of the apertured disk 11 and after the component 2 is 
fastened to the container 5, this projection 12 is pressed from above on 
the radial outer area of the apertured disk which thereby is clamped and 
tightly held in position. FIG. 1 shows the apertured disk in the closed 
position of the inlet check valve. In that case the inner rim of the 
apertured disk 11 rests in sealing engagement with the conical surface of 
the element 9. The thickness of the apertured disk 11 is gradually tapered 
in the radial inner area thereof toward the inner rim. 
An annular wall in the form of a downwardly projecting collar 13 is 
provided in the component 2 of the headpiece 1. This annular collar 13 
forms a section of the wall of the pump chamber 7. The free lower rim of 
the collar 13 ends at a distance above the support base 8. As the result 
thereof an annular gap 14 is provided which connects the pump chamber 7 to 
a chamber 15 which in turn merges into and communicates with the discharge 
channel 3. An outlet check valve is provided to seal the communication 
path of annular gap 14 between the pump chamber 7 and the discharge 
channel 3. The closure member of the outlet check valve is designed as an 
elastically flexible and conically flaring annular wall 16 arranged 
concentrically with the apertured disk 11 and integrally joined at its 
lower narrower end to the disk 11. When the outlet check valve is in the 
closed position, the inner surface of annular wall 16 rests against the 
free rim of collar 13 so as to be circumferentially sealing and thereby 
closes the annular gap 14. 
The operation of the dispenser of FIG. 1 will now be described below. A 
paste-like substance is located inside the container 5 between the piston 
6 and the support base 8. In order to dispense an amount of this 
substance, the sealing cap 17 first is removed from the feed orifice of 
the discharge channel 3. Both the closure members of the inlet and outlet 
check valves are in the closed position shown in FIG. 1. By pushing-in the 
cap 4, using for instance a finger, the volume of the pump chamber 7 
drops. Excess pressure is generated thereby, which forces the inner rim of 
apertured disk 11 in sealing engagement with the conical surface of the 
element 9. Simultaneously the increased interior pressure causes outward 
bulging of the conical annular wall 16, so that an annular gap 14 is 
created between said conical annular wall and the free end of the collar 
13. If at the beginning of the procedure there already was paste-like 
material in the pump chamber, this material then is forced by the higher 
pressure through the annular gap 14 into the chamber 15 and from there 
into the discharge channel 3, and through the orifice of the discharge 
channel it then reaches the outside. The moment the force on the cap 4 
ends, this cap elastically resumes its initial shape and the volume of the 
pump chamber again enlarges. The partial vacuum so generated causes the 
conical annular wall 16 to elastically resume its initial position whereby 
it comes to rest against the lower rim of collar 13 and thereby again 
seals the pump chamber 7 from the discharge channel. Simultaneously the 
vacuum causes an upward bulging of the radial inner area of the apertured 
disk 11, whereby its inner rim lifts off the conical surface of the 
element 9 and provides an annular slit. Due to the pressure difference 
between the higher atmospheric pressure and the vacuum in the pump 
chamber, the piston 6 is forced upward. As a result paste-like material is 
moved through the open annular slit into the pump chamber 7. The moment 
the pressure in the pump chamber 7 has come up to atmospheric, the 
upwardly curved radial inner area of apertured disk 11 elastically moves 
down, whereby the inner rim of the disk comes to rest against the surface 
of the element 9 and the inlet check valve is closed. Thereupon the 
dispensing process already described can start again. 
FIG. 2 illustrates an axial section of the upper region of a second 
embodiment of the dispenser. To the extent the components of this second 
embodiment are the same as those of the embodiment of FIG. 1, they are 
denoted by the same reference numerals. These components therefore will 
not be described again. The lower part of the container, not shown in FIG. 
2, can be of the same design as in FIG. 1. 
In the embodiment of FIG. 2 a single apertured disk 18 made of a highly 
elastic plastic is provided as the closure member both for the inlet check 
valve and the outlet check valve; in the closed position, the inner rim of 
disk 18 rests in sealing engagement with the conical surface of the 
element 9. Accordingly the radial inner area of the apertured disk 18 
forms the closure member of the inlet check valve. The upper surface of 
annular section 19 located in the radial direction approximately centrally 
between the inner rim and the radial outer area of the apertured disk 18 
and facing the pump chamber acts as the closure member for the outlet 
check valve. When the outlet check valve is in the closed position, the 
annular section 19 of apertured disk 18 rests against the lower rim of 
annular collar 20 arranged coaxially with the apertured disk and integral 
with component 2' of the headpiece 1. The annular collar 20 forms a 
section of the wall of the pump chamber 7. 
If the volume of the pump chamber 7 of the dispenser of FIG. 2 is decreated 
by depressing the cap 4, then the inner rim of the apertured disk 18 will 
also be forced in sealing engagement with the conical element 9 which then 
supports it. The inlet check valve is thus closed. Simultaneously the 
pressure in the pump chamber causes the apertured disk 18 to curve 
downward in the area between the inner rim and the radial outer, clamped 
area thereof. As a result the annular section 19 moves away from the lower 
rim of the annular collar 20. Any paste-like substance in the pump chamber 
can pass through the generated annular slit into an annular space 21 
externally surrounding the annular collar 20 and from there into the 
discharge channel 3. In the course of a subsequent increase in volume upon 
load-relief of the cap 4, the apertured disk 18 elastically resumes its 
plane position, whereby the annular section 19 again sealingly engages the 
lower rim of the annular collar 20 and thereby closes the outlet check 
valve. Because of the vacuum so generated in the pump chamber 7, the 
radial inner area of apertured disk 18 is simultaneously curved upward 
with the apertured disk resting against the free lower rim of the annular 
collar 20. Thereupon the atmospheric pressure forces the paste-like 
substance from the inside of the container 5 through the annular slit 
resulting between the inner rim of the apertured disk 18 and the conical 
element 9 into pump chamber 7. The moment the pressure in the pump chamber 
reaches atmospheric, the radial inner area of apertured disk 18 
elastically returns to its initial position and closes the inlet check 
valve. Thereupon the dispensing process can be repeated. 
FIG. 3 is an axial section of the upper region of a third dispenser 
embodiment. To the extent the components in this embodiment are the same 
as those of the illustrative embodiments shown in FIGS. 1 and/or 2, they 
are also denoted by the same reference numerals. Accordingly, such 
components will not be discussed again. In this embodiment the apertured 
disk 18 is used solely as the closure member for the inlet check valve. 
Walls supporting circumferential projection 12 are integral with component 
2" of the headpiece 1 and laterally define the pump chamber 7. An opening 
22 in one of these defining walls represents the communication path 
between the pump chamber 7 and the discharge channel 3. An inset 23 made 
of an injection-molded plastic is mounted in the discharge channel 3 and 
is integrally provided by means of a narrow hinge strap with a flap 24. 
This flap 24 in the closed position externally covers the opening 22. If 
the pressure in the pump chamber exceeds atmospheric, the flap 24 is 
elastically pivoted outward and thus opens the communication path between 
the pump chamber and the discharge channel. The embodiment of FIG. 3 
operates similarly to those of the dispensers of FIGS. 1 and 2. 
FIG. 4 shows the axial section of a fourth embodiment of the dispenser of 
the present invention. To the extent the components of this fourth 
embodiment are the same as those of the illustrative embodiments shown in 
FIGS. 1 and/or 2 and/or 3, they are also denoted by the same reference 
numerals and will not be discussed again. In this embodiment, the support 
base 8' is a component of the headpiece 1 and the apertured disk 11' is 
held in place in the headpiece. 
The invention is not restricted to the shown illustrative embodiments. It 
is possible for instance to make use of a component of the headpiece as 
the support base and to hold the apertured disk in place in the headpiece. 
Again it is possible for instance to design the connection between the 
headpiece and the container as a detachable connection such as a screw 
connection. Such a design makes it possible to make the container 
disposable and to market such disposable containers separately from the 
headpiece. The container proper can be designed to be especially simple 
and to be manufactured economically. Prior to use the filled disposable 
container may be sealed at its free upper end by a foil to be removed 
before joining the container to the headpiece. 
While it is very advantageous for the dispenser of the invention to design 
the valve seat of the first check valve as a frustrum of a cone with 
symmetry of rotation and straight generatrix, deviations from such a 
design and within the scope of the invention are nevertheless possible. 
For instance the valve seat may assume the geometry of an upwardly 
tapering body of rotation with a curved generatrix. Again it is possible 
within the scope of the invention to use upwardly tapering valve seats 
which lack symmetry of rotation. In that case the apertured disk must be 
replaced by a disk of which the opening is suitably fitted to the contour 
of the valve seat. Such a geometry may be appropriate for instance when 
the outer shape of the dispenser is desired to deviate from symmetry of 
rotation, being illustratively rectangular. 
All features found in the description and the drawing furthermore can be 
combined in arbitrary manner to remain within the scope of the invention.