DE102020114997A1 - Sieve for a soda lime canister and method for making a soda lime canister - Google Patents

Abstract

The present invention relates to a sieve (10a; 10b 10c) for a soda lime container (20), having a base body (11) and at least one energy director (13) positioned on the outer peripheral surface (12) of the base body (11) for welding the sieve (10a) ; 10b; 10c) with a container wall (21) of the soda lime container (20), the at least one energy director (13) having an energy introduction edge (14) and the cross section of the energy director (13) decreasing towards the energy introduction edge (14), wherein a sieve direction (15) of the base body (11) extends orthogonally to an extension direction (16) of the energy introduction edge (14). The invention also relates to a method for producing a soda lime container (20) using a sieve (10a; 10b; 10c) according to the invention.

Description

The present invention relates to a sieve for a soda lime container, having a base body and at least one energy director positioned on the outer peripheral surface of the base body for welding the sieve to a container wall of the soda lime container, the at least one energy director having an energy introduction edge and the cross section of the energy director to the energy introduction edge downsized. The invention also relates to a method for producing such a soda lime container.

STATE OF THE ART

Generic soda lime containers are filled with so-called soda lime. Soda lime usually has a mixture of calcium hydroxide and sodium hydroxide, other compositions of matter such as a mixture of potassium hydroxide and barium hydroxide are also known. Soda lime is used to bind the carbon dioxide contained in the exhaled air, for example to prevent the harmful effects of an excessively high carbon dioxide content in the inhaled air in closed-circuit breathing apparatus and pendulum breathing apparatus.

In the case of known soda lime containers, a distinction can be made between disposable containers for soda lime and reusable soda lime containers. In the case of disposable containers in particular, it is always a challenge to create a soda lime container in a simple and inexpensive manner that also has a sufficiently high storage and transportability. In addition, the manageability during maintenance and preparation for use in a closed loop breathing apparatus should be as simple as possible.

Various systems and methods are known for producing disposable containers of the generic type. In one of these methods soda lime is poured into an open container in the form of bulk material. A sieve is then placed on the soda lime as a lid to cover the soda lime in the container. As soon as the sieve is in the desired position, it is welded to the housing or a container wall of the later soda lime container using an ultrasonic welding process. For this purpose, known sieves have so-called energy directors on an outer circumferential surface of a base body. Generic energy directors are designed triangular or roof-shaped, the tip or roof edge of the energy director or the energy director each extending parallel to a sieve direction or a longitudinal or height direction of the container. As a result, the energy directors are each in point form on an inner wall of the container which, due to manufacturing technology, is usually slightly funnel-shaped or has a slight conicity. This results in a partially unsatisfactory energy transfer between the sieve and the container during the ultrasonic welding process. As a result, the welding process takes longer than desired and / or does not lead to the desired connection strength between the screen and the housing. In addition, the known method cannot be used with any arbitrary filter shape. In addition, the points of contact between the sieve and the housing lead to poor process reliability and uneven welding points between the energy directors and the housing wall.

The most widespread method for connecting a generic screen to the container wall is anvil welding. The sieve is connected to a fixed stop on the container. A disadvantage of this solution is the non-variable filling level when filling the container with soda lime. This leaves no scope for compensating for process-related fluctuations that occur due to the properties of the soda lime. This in turn results in a transport and storage capability that is in need of improvement.

DISCLOSURE OF THE INVENTION

The object of the present invention is to at least partially take into account the problems described above. In particular, the object of the invention is to create a device and a method for the inexpensive, simple and / or, with regard to the storability, transportability and / or manageability of a soda lime container, satisfactory manufacture of a soda lime container.

The above object is achieved by the claims. In particular, the above object is achieved by a sieve according to claim 1 and a method according to claim 7. Further advantages of the invention emerge from the subclaims, the description and the figures. Features that are described in connection with the sieve naturally also apply in connection with the method according to the invention for producing the soda lime container and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made and / or can be reciprocated.

According to a first aspect of the present invention, a screen for a soda lime container is provided. The sieve has a base body and at least one on the Energy director positioned on the outer circumferential surface of the base body for welding the screen to a container wall of the soda lime container. The at least one energy director has an energy introduction edge, and the cross section of the energy director decreases in size towards the energy introduction edge. A sieve direction of the base body extends orthogonally to a direction of extent of the energy introduction edge.

The system known in the prior art for welding the sieve to the container wall of the soda lime container has been further developed so that the at least one energy director or the energy introduction edge is now orthogonal to the sieve direction and consequently also orthogonally to one during the welding process for welding the sieve to the container wall Extends height or longitudinal direction of the container wall. In comparison to the known system in which the energy introduction edge extends parallel to the sieve direction and therefore the point contact between the sieve and the container wall described in the introduction is present during the ultrasonic welding process, a line contact can now be created. As a result, less energy is required during the welding process and yet less time is required for a consistently good welding result. In addition, a welded joint with an improved joint strength can be created. The advantage over the widespread anvil welding is, in particular, that the height of the screen can be welded to the container wall in a relatively variable manner. This enables a permanent fixation of a homogeneous pack.

The invention relates in particular to a sieve for a disposable soda lime container for a closed loop breathing apparatus. That is to say, the proposed sieve is suitable for closing a container filled with soda lime by means of ultrasonic welding to produce a functioning soda lime container. The proposed sieve can, however, not only be used for disposable soda lime containers, but also for the production of other bulk material containers, for example containers for activated carbon filters and / or carbon dioxide filters.

The sieve and in particular the main body of the sieve can have different geometric shapes. The base body is preferably designed in the form of a disk with a height that is less than a width and / or a diameter of the base body. Such a sieve can also have a curved design. That is to say, the sieve can have a curvature on a sieve upper side or a sieve inlet surface and / or a sieve underside or a sieve outlet surface. The height of the base body extends in a height direction which can also be understood as the sieve direction and / or as a flow direction, that is to say a functional direction of the sieve or the base body. The disk shape is not to be considered limited to a circular disk shape. Thus, according to a preferred embodiment variant, the basic body of the screen can also be configured, for example, rectangular with rounded corners and / or edges. The sieve direction can extend in a three-dimensional coordinate system in a y-direction, while a width direction and / or a diameter direction extends in an x-direction and / or a z-direction. In this case, the direction of extent runs in the z direction, in the y direction and / or on a circular path in an x-z plane or parallel to the x-z plane. The direction of extension of the energy introduction edge out of the x-z plane is also possible as long as the energy introduction edge does not extend parallel to the sieve direction. The extension of the sieve direction orthogonal to the energy introduction edge can also be understood to mean an extension of the sieve direction orthogonally to a tangent array along the energy introduction edge, which has a curved course. The sieving direction can also extend parallel to and / or directly on an axis of rotation of the base body, provided that the base body is configured as a body of rotation, for example cylindrical or essentially cylindrical.

The soda lime container is to be understood in particular as a carbon dioxide soda lime container for binding carbon dioxide. The energy introduction edge can be understood as a linear end section of the energy director. In the case of a triangular and / or roof shape of the energy director, the energy introduction edge could therefore be viewed as the ridge of the roof shape, which extends or essentially extends in a longitudinal direction, straight or odd, in the extension direction. The energy introduction edge does not necessarily have to be pointed. A rounded edge with a curve radius in the millimeter range or smaller is also possible. The outer circumferential surface is designed in particular on an outer wall section of the main body pointing away from the main body. The normal vector of this outer wall section preferably extends orthogonally to the sieve direction. The normal vector can also extend orthogonally to an extension direction of an energy introduction edge of an energy director, which is located on the outer circumferential surface partially at the same position as the normal vector.

The base body is preferably designed for welding the sieve to an inner circumferential surface of the container wall. The at least one energy director can with a predefined minimum distance to a corner and / or edge of the base body be configured on the base body. If the base body is, for example, rectangular or essentially rectangular, for example with rounded corners and / or edges, several energy directors can be configured on side surfaces of the base body, the energy directors being at a minimum distance of, for example, several millimeters or several centimeters from the corners of the base body . In this way, excessive energy input to the base body can be prevented, which could weaken the material of the base body and / or a connection point between the base body or the sieve and the container wall. This in turn prevents damage and / or destruction of the finished soda lime container when using the soda lime container. The side surfaces are to be regarded as the four surfaces, for example, which have a significantly smaller area than the two top surfaces of the base body. The normal vector of the two top surfaces each extends in the sieve direction.

According to a further embodiment variant of the present invention, it is possible for the sieve to have several energy directors spaced apart from one another, each with an energy introduction edge, the sieve direction extending perpendicular to each energy introduction edge. The energy directors can consequently be configured one behind the other in a circumferential direction around the base body, the energy introduction edge extending along the circumferential direction. In the case of a disk-shaped base body with a circular outer circumference, the energy introduction edges can, for example, each have the same radius of curvature and / or can be located on the same circular path. This allows the sieve to be connected quickly and stably to the container wall.

It can be correspondingly advantageous if the energy introduction edge in a sieve according to the present invention is located on a circular path which extends concentrically to the outer circumferential surface of the base body. A particularly uniform connection of the sieve to the container wall can thus be achieved in a simple manner.

In addition, it is possible for a single energy director to extend annularly around the base body in the case of a sieve according to the invention. By means of such an energy director, a particularly uniform and stable connection of the sieve to the container wall can also be achieved. It can be of further advantage here if the ring-shaped energy director has a circular energy introduction edge which is configured concentrically to the outer circumferential surface of the base body. In this embodiment, a dust-tight and / or gas-tight connection between the sieve and the container is possible. This means that bulk material can be safely enclosed in the breathable container or another bulk material container. In particular, no dust can get through between the sieve and the housing wall.

In addition, in the case of a sieve according to the present invention, it is possible for the at least one energy director to be a monolithic component of the base body. The sieve including the at least one energy director can thus be made available in a robust manner. Furthermore, separate process steps such as the injection molding of energy directors onto the base body can be dispensed with. The sieve can thus be made available relatively inexpensively.

• - Bereitstellen einer rohrförmigen Behälterwandung,
• - Positionieren eines wie vorstehend im Detail beschriebenen Siebs mit der Energieeinleitungskante des wenigstens einen Energierichtungsgebers an einer Innenumfangsfläche der Behälterwandung und
• - Verschweißen des Siebs mit der Behälterwandung über den wenigstens einen Energierichtungsgeber mittels Schweißen, insbesondere mittels Ultraschallschweißen.

According to a further aspect of the present invention, a method for producing a soda lime canister for a breathing apparatus is provided. The procedure consists of the following steps:

• - Provision of a tubular container wall,
• Positioning a sieve as described in detail above with the energy introduction edge of the at least one energy director on an inner circumferential surface of the container wall and
• - Welding the sieve to the container wall via the at least one energy director by means of welding, in particular by means of ultrasonic welding.

The method according to the invention thus brings the same advantages as have been described in detail with reference to the sieve according to the invention. The tubular container wall can in particular be understood to mean a hollow cylinder with a circular, elliptical or angular cross section. Furthermore, a tubular, slightly funnel-shaped container wall or a tubular container wall with a slight conicity is preferably made available.

Further measures improving the invention emerge from the following description of various exemplary embodiments of the invention, which are shown schematically in the figures. All of the features and / or advantages arising from the claims, the description or the figures, including structural details and spatial arrangements, can be essential to the invention both individually and in the various combinations.

• 1 eine geschnittene Seitenansicht eines Siebs gemäß einer ersten Ausführungsform der vorliegenden Erfindung,
• 2 eine Draufsicht auf das Sieb gemäß der ersten Ausführungsform der vorliegenden Erfindung,
• 3 eine geschnittene Seitenansicht eines Siebs gemäß einer zweiten Ausführungsform der vorliegenden Erfindung,
• 4 eine Seitenansicht eines Siebs gemäß der zweiten Ausführungsform der vorliegenden Erfindung,
• 5 eine Draufsicht auf das Sieb gemäß der zweiten Ausführungsform der vorliegenden Erfindung,
• 6 eine geschnittene Seitenansicht eines Siebs gemäß einer dritten Ausführungsform der vorliegenden Erfindung,
• 7 eine Draufsicht auf das Sieb gemäß der dritten Ausführungsform der vorliegenden Erfindung,
• 8 eine Darstellung zum Erläutern eines Verfahrens zum Herstellen eines Atemkalkbehälters gemäß einer bevorzugten Ausführungsform,
• 9 ein Flussdiagramm zum Erläutern eines Verfahrens gemäß der bevorzugten Ausführungsform,
• 10 einen durch das erfindungsgemäße Verfahren hergestellten Atemkalkbehälter und
• 11 eine Darstellung zum Erläutern eines im Stand der Technik bekannten Verfahrens zum Herstellen eines Atemkalkbehälters.

They each show schematically:

• 1 a sectional side view of a screen according to a first embodiment of the present invention,
• 2 a plan view of the sieve according to the first embodiment of the present invention,
• 3 a sectional side view of a screen according to a second embodiment of the present invention,
• 4th a side view of a screen according to the second embodiment of the present invention,
• 5 a plan view of the sieve according to the second embodiment of the present invention,
• 6th a sectional side view of a screen according to a third embodiment of the present invention,
• 7th a plan view of the sieve according to the third embodiment of the present invention,
• 8th a representation to explain a method for producing a soda lime container according to a preferred embodiment,
• 9 a flowchart for explaining a method according to the preferred embodiment,
• 10 a soda lime container produced by the method according to the invention and
• 11th an illustration to explain a method known in the prior art for producing a soda lime container.

Elements with the same function and mode of operation are each provided with the same reference symbols in the figures.

1 shows a sieve 10a for use in an in 10 shown soda lime container 20th according to a first embodiment. The sieve shown 10a has a base body 11th on. On the outer peripheral surface 12th of the main body 11th are several energy directors positioned at a distance from one another 13th for welding the screen 10a with a container wall 21 of the soda lime canister 20th designed. The energy directors 13th each have an energy introduction edge 14th on, with the cross-section of the energy director 13th each to the energy introduction edge 14th downsized. One sieve direction 15th or functional direction of the base body 11th or the sieve 10a extends orthogonally to the directions of extension 16 the energy introduction edges 14th . In other words, the direction of extension 16 every energy introduction edge 14th runs orthogonally to the sieve direction 15th . With reference to the coordinate system shown, it can also be seen that the sieve direction 15th extends along the y-direction and the direction of extension 16 or at least one tangent along the direction of extent 16 runs in the z-direction. The in 1 The example shown extends the direction of extent 16 or the tangents extend along the extension direction 16 in a plane parallel to the xz plane.

In 2 is the sieve 10a shown in a top view. There it can be seen in particular that the energy introduction edges 14th each on the same circular path that is concentric to the outer circumferential surface 12th of the main body 11th extends, are located.

In the 3 until 5 is a sieve 10b shown according to a second embodiment. According to this embodiment variant, a single energy director extends 13th ring-shaped around the body 11th hereabouts. The ring-shaped energy director 13th has a circular energy introduction edge 14th on that are concentric to the outer peripheral surface 12th of the main body 11th is designed. In addition, it is the energy director 13th in the embodiment shown, a monolithic component of the base body 11th .

In the 6th and 7th is a sieve 10c shown according to a third embodiment. The basic body 11th this sieve 10c is not circular in a plan view, but rather square or essentially square with rounded corners. The sieve shown 10c has four energy directors 13th on the four different side sections of the outer circumferential surface pointing away from one another 12th of the main body 11th are designed.

With reference to the 8th and 9 a method for producing the in 10 shown soda lime canister 20th for a breathing apparatus explained. In a first step S1, a soda lime is initially used 23 filled container with a tubular container wall 21 provided. In a second step S2, a sieve as described above 10b with the energy introduction edge 14th on an inner peripheral surface 22nd the container wall 21 positioned. In a third step S3 the sieve 10b via the energy director 13th by means of ultrasonic welding with the container wall 21 welded. This is done in one direction 30th a mechanical vibration 31 in the energy director 13th initiated and from there onto the container wall 21 transfer. One made by the process, with soda lime 23 filled soda lime container 20th is in 10 shown.

In 11th is a sieve 10d with a base body 11th shown on which the energy directors previously used in the prior art 13th are designed, the energy introduction edge 14th parallel to the sieve direction 15th extends.

In addition to the illustrated embodiments, the invention permits further design principles. That is to say, the invention should not be viewed as restricted to the exemplary embodiments explained with reference to the figures.

List of reference symbols

10a

Sieve

10b

Sieve

10c

Sieve

10d

Sieve

11th

Base body

12th

Outer peripheral surface

13th

Energy director

14th

Energy introduction edge

15th

Sieve direction

16

Direction of extension

20th

Soda lime container

21

Container wall

22nd

Inner peripheral surface

23

Soda lime

30th

Direction of introduction

31

mechanical vibration

Claims (7)

Sieve (10a; 10b 10c) for a soda lime container (20), having a base body (11) and at least one energy director (13) positioned on the outer circumferential surface (12) of the base body (11) for welding the sieve (10a; 10b; 10c) with a container wall (21) of the soda lime container (20), wherein the at least one energy director (13) has an energy introduction edge (14) and wherein the cross section of the energy director (13) decreases towards the energy introduction edge (14), characterized in that a Sieve direction (15) of the base body (11) extends orthogonally to an extension direction (16) of the energy introduction edge (14). Sieve (1 0a; 10c) after Claim 1 , characterized by several energy directors (13) spaced from one another, each with an energy introduction edge (14), the sieve direction (15) extending perpendicular to each energy introduction edge (14). Sieve (10a) Claim 2 , characterized in that the energy introduction edge (14) is located on a circular path which extends concentrically to the outer circumferential surface (12) of the base body (11). Sieve (10b) Claim 1 , characterized in that a single energy director (13) extends annularly around the base body (11) Sieve (10b) Claim 4 , characterized in that the ring-shaped energy direction transmitter (13) has a circular energy introduction edge (14) which is designed concentrically to the outer circumferential surface (12) of the base body (11). Sieve (10b) according to one of the preceding claims, characterized in that the at least one energy director (13) is a monolithic component of the base body (11). Method for producing a soda lime canister (20) for a breathing apparatus, comprising the steps: - Provision of a tubular container wall (21), - Positioning a sieve (10a; 10b; 10c) according to one of the preceding claims with the energy introduction edge (14) of the at least one energy director (13) on an inner peripheral surface (22) of the container wall (21), and - Welding the sieve (10a; 10b; 10c) to the container wall (21) via the at least one energy director (13) by means of welding.

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