JPS6135069B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention consists of a rigid outer container and an elastic inner container fixed to the outer container at its upper edge for containing and discharging liquid and pasty products under pressure. The container includes a valve-carrying lid fitted onto the upper edge of the outer container, a discharge valve disposed on the valve-carrying lid and extending into the inner container, and a valve-carrying lid fitted on the upper edge of the outer container, and a discharge valve disposed on the valve-carrying lid and extending into the inner container, and and a working gas filled in the free space between the two.

In such containers, which are also referred to as pressure cans or spray cans, the working gas (Treibgas), upon actuation of the discharge valve, forces the product present in the inner container outwards through the opened discharge valve. The inner container is then increasingly compressed. Finally, all the product contained in the inner container is pressed out. The inner container takes the form of a compressed hose or a compressed sausage. However, the inner container may not be compressed uniformly over its entire length. The inner container is directly throttled with a drain valve. Due to the constriction thereby effected, the product remaining in the remainder of the inner container cannot be compressed. This represents a loss of valuable product.

In order to avoid this loss, various shapes have been given to the inner container. Spray cans are known which consist of a rigid outer container and a flexible inner container disposed therein. The inner container has its upper edge secured to the outer container. The jacket is ribbed in accordion fashion and has a corresponding corrugation. These waveforms run circumferentially. Upon opening of the discharge valve which enters the inner container, the overpressure existing between the outer container and the inner container acts and presses the inner container in such a way that the longitudinally ribbed walls approach each other. The inner container is compressed like an accordion. This compression ends when the outer surfaces of the walls forming the ribs lie side by side. The wall thickness of the container and the number of ribs or creases thereby determine the quality of the empty state of the container. Complete blanking is impossible. A residual volume inevitably remains in the inner container. This means that the inner container is never compressed in an ideal manner only in the direction of its longitudinal axis. This drawback can be suitably improved by reducing the wall thickness of the folded line portion. Different wall thicknesses and a relatively high number of ribs or creases increase production costs (Swiss patent 447968
Publication No.).

Furthermore, other spray cans are known in which the side container is provided with a number of longitudinally running fold lines. In horizontal section, this spray can has the shape of a flat tank or recess. This fold line follows a controlled folding of the inner container. The inner container is compressed uniformly over its entire length. This shape of the inner container is only used if its outer circumference substantially coincides with the inner circumference of the outer container. However, in order for the inner container to be sufficiently compressed even with losses of working gas, it is often necessary for the inner container to have a substantially small circumference (DE 2103477).

Starting from this state of the art, the invention provides that the inner container can be designed in such a way that it is completely emptied when attached to a larger outer container, has a highly effective utilization volume, and is inexpensive to manufacture and assemble. as the basis of the task.

In order to solve this problem, the present invention provides a container of the type mentioned at the outset, in which the cross section of the inner container has the form of at least three circular arc sections, the arc sections running in the longitudinal direction and the cross sectional contour forming an obtuse angle. The material is interconnected by striations of material.

The pressure exerted by the working gas in the intermediate chamber between the two containers acts on this cross section of the inner container. Due to the shape according to the invention, the inner container does not have uniform strength over its entire circumference. The intensity is minimal at the center of each arc portion. The inner container is then hollowed out and folded inward under a tridental formation. The inner container is thereby folded in a controlled and uniform manner over its entire length. In the final state, the inner container assumes the shape of a star of three bags or of at least three bags. Along the centerline or center of the star, the hollow conduit remains open through which the product can rise upwards to the discharge valve. This ensures almost complete blanking of the inner container.

It is expedient for the radius of curvature R of the arcuate portion to be greater than the radius of curvature r around which the material striations are curved in the circumferential direction. As a result, the strength of the arc section against the pressure acting on the material strip is always less than the strength of the material strip. The inner container must first be folded in forcefully along the central region of the arc section.

A measure in which the thickness of the material striation exceeds the thickness of the arc is useful for a similar purpose. This makes the material striations even stronger and more rigid and resists compression.

The inner container according to the invention is low in cost due to its smooth shape. Possible materials include flexible materials, in particular synthetic resins or soft aluminum.

Preferably the inner container consists of three arcuate sections. However, it can also consist of four or more circular arc sections.

Other configurations are contemplated in which the material threads have a folded configuration with webs located radially outwardly and pressed against the inner surface of the outer container.
These webs are pressed against the inner surface of the outer container due to the internal pressure exerted by the product when filling the inner container and prevent the inner container from sliding downwards in the outer container due to the weight of the product. blocked.

When the inner container is filled, the web is pressed against the inner surface of the outer container with such pressure that it becomes sticky. This adhesion exerts a large frictional force that prevents the inner container from sliding downward. It is ensured that the inner container is not drawn into the outer container by the weight of the filling. The upper edge between the upper edge of the outer container and the valve-carrying lid and the fastening part of the inner container are therefore not loaded.

Next, the illustrated embodiment will be explained.

1 to 4 show an outer container 12 having a bottom 14, a stopper 16 closing the filling opening at the bottom;
It is held by a dome-shaped top 18 which is connected to the jacket of the outer container via a lower flanged edge 20, and an upper flanged edge 22 and carrying lid 24 in which a valve carrying lid 24 is suspended. and a discharge valve 26. The inner container 28 is open at its upper end and has a rim 30.
has. With this 30, the inner container has a flange edge 2.
2 is suspended and tightened. Inner container 2
8 and the outer container 12 there is a gas chamber 32 . The inner container 28 consists of three arcuate sections 34 and connected material threads 36. In FIG. 4, the radius of the arc portion 34 is indicated by R. The small radius of the material striation 36 is designated r.

1, 2 and 4 show that the thickness of the material striations 36 exceeds the thickness of the arcuate portions 34. FIGS.
The inner container 28 is connected to the outer container 1 on the outer circumferential surface in the range of this material striation 36, which is a protruding edge extending in the longitudinal direction.
2, and in this case, two tangent lines at arbitrary points on both sides of the protruding edge on the outer circumferential surface in the area of the material filament 36 form an obtuse angle with each other when viewed in cross section of the filament.

Figure 5 shows the shape of the inner container when completely filled. The arrow indicates the main direction of action of the pressure exerted by the working gas in the gas chamber 32.
Due to the difference in the strength of the inner container relative to the external pressure, the external pressure is firstly perceptible in the central region of the arcuate section 34. That portion is pushed into the shape shown in FIG. 6 as the inner container begins to empty. When completely emptied, it will be compressed to the shape shown in FIG. Only the central flow-through channel 42 remains open. Around this through-flow channel, the inner container assumes an active star shape 44. This shape extends throughout the entire length. As a result, the product initially contained in the inner container can completely flow out via the flow-through line 42.

In the embodiment shown in FIGS. 8 to 10, the material strip 36 is replaced by a fold 38. The folded part is connected to the outer container 1 by the web 40.
is in contact with the inner surface of This web rests against the outer container 12 by a frictional connection. The web prevents the inner container from sliding down due to the weight of the product. Other blanking is done in a manner similar to that described for FIGS. 1-7.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a first embodiment of the pressure canister according to the present invention, Fig. 2 is a transverse sectional view taken along line 2-2 in Fig. 1, Fig. 3 is a side view of the inner container, and Fig. 4. is a cross-sectional view taken along line 4-4 in Figure 3, Figure 5 is a cross-sectional view of the inner container and outer container as they begin to empty, and Figure 6 is a cross-sectional view of the inner container and outer container during emptying of the inner container. 7 is a sectional view of the inner container and the outer container after blanking of the inner container; FIG. 8 is a side view of a second embodiment of the inner container; FIG. 9 is a cross-sectional view of the outer container. 8 and FIG. 10 shows a top view of the embodiment of the inner and outer containers shown in FIG. 9, respectively. Reference numerals in the figure, 28...Inner container, 34...Circular arc portion, 36...Material linear portion.

Claims (1)

Claims: 1. Container for containing and discharging liquid and pasty products under pressure, consisting of a rigid outer container and an elastic inner container fixed to the outer container by its upper edge. a valve-carrying lid fitted over the upper edge of the outer container, a discharge valve disposed on the valve-carrying lid and extending into the inner container, and a free space between the outer container and the inner container; and a working gas, the inner container 28 has at least three arcuate sections 3 in cross section.
4, the inner container is press-fitted into the outer container, and on the outer circumferential surface in the area of the material striations 36, at any point on either side of the protruding edge when viewed in cross section of the striations.
The two tangent lines make an obtuse angle with each other, and the outer circumferential surface of the range of this material striation 36, which is a protruding edge extending in the longitudinal direction, is crimped to the inner surface of the outer container and frictionally connected to the outer container. , characterized in that the radius of curvature R of the circular arc portion 34 is larger than the radius of curvature r of the portion where the material filament 36 is curved in its circumferential direction, for storing and discharging liquid and pasty products. container. 2. The container according to claim 1, wherein the thickness of the material striated portion 36 is greater than or equal to the thickness of the arc portion 34. 3. According to claim 1 or 2, the material striations are located radially outward and have the form of a folded portion forming a web 40 that is crimped onto the inner surface of the outer container 12. Container as described. 4. A container according to claim 3, wherein the web 40 is connected to the inner surface of the outer container 12 by frictional forces.