DE202020102593U1 - Mouth-nose protection in the form of a blank made of bendable and / or foldable, transparent material, in particular for use as infection protection - Google Patents

Abstract

Mouth-nose protection (10) in the form of a blank (12) made of bendable and / or foldable, transparent material, on which at least one connecting element (30) is provided, the blank (12) and the connecting element (30) being such are designed so that the blank (12) can be brought from a compact transport state into a usable state suitable for the head covering, the size and shape of the blank (12) and the at least one connecting element (30) being selected such that the blank ( 12) can be temporarily fixed in the use state with the aid of the connecting element (30), the use state allowing an at least predominant horizontal encirclement of the head of a human user in the area of the eyes, nose and mouth.

Description

The invention relates to a head covering in the form of a blank made of bendable and / or foldable, transparent material, in particular for use as infection protection.

Various infection protection devices for the mouth-nose area of humans are known from practice, in particular simple paper or fabric masks, mouth-nose protection devices known from medicine and particle-filtering respiratory masks, which depend on the filter class (FFP1, FFP2 and FFP3 ) protect against inhalation of microparticles. The known infection control devices have the disadvantage that they largely cover the face of the wearer, as a result of which a large part of the facial expressions and thus the possibility of perceiving important parts of the face is lost.

In addition to the protective devices mentioned, there are face shields known in particular from non-medical fields, such as protective shields known from welding and soldering technology, which consist of mostly arc-shaped, shield-like transparent elements which can be attached to the head by means of a headband or headband, by means of a spectacle frame or by means of a helmet. The disadvantage of these face shields is that they are very bulky on the one hand and that it is very cumbersome to carry around when needed. On the other hand, these face shields only offer frontal protection and are not or only partially suitable as protection against infection, because in particular from the side or from behind, droplets and other particles can get into the area between the face shield and the mouth and nose area of the wearer.

The invention has for its object to provide an infection control that is inexpensive to manufacture and avoids the disadvantages mentioned above.

The object is achieved according to the invention with the features of the independent claims. Further practical embodiments and advantages of the invention are described in connection with the dependent claims.

A mouth-nose protection according to the invention comprises at least one blank made of bendable and / or foldable, transparent material, on which at least one connecting element is provided. The blank and the connecting element are designed in such a way that the blank can be brought from a compact transport state into a usable state suitable for at least the majority of the head wrap, the size and shape of the blank and the at least one connecting element being selected such that the blank is in can temporarily fix the useful condition with the aid of the connecting element, the useful condition allowing at least predominant horizontal encirclement of the head of a human user in the area of the eyes, nose and mouth. In this context, predominantly encircling means that the head is encased at least 75 percent, i.e. the mouth-nose protection when in use - in a view from above of a head - extends over a circumferential angle of at least 270 degrees. Preferably, the mouth-nose protection extends over an angle of at least 300 degrees, more preferably over an angle of at least 330 degrees and particularly preferably over an angle of 360 degrees, i.e. completely enclosing the head. With "in the area of the eyes, nose and mouth" is meant the extension of the mouth-nose protection in the vertical direction of the head.

The mouth-nose protection according to the invention is therefore all-round protection or almost all-round protection. This not only ensures excellent protection against particles, droplets and other external influences, but a person wearing mouth-nose protection is also well protected from himself to the extent that accidental touching of the mouth, nose or eye while wearing it can be prevented with a suitable design because these parts of the face cannot be reached by the hand of the person wearing it.

In comparison to the mouth and nose protectors known from the prior art, the invention has the further advantage that the person wearing it has to breathe in less exhaled CO ₂ again, because there is better air circulation within the protected inner area. The cleaning of the mouth and nose protection according to the invention is also simple and can be carried out in particular while it is being worn. In this respect, it is possible to carry out the cleaning before the mouth-nose protection is removed, which further reduces the risk of infection.

Furthermore, it is possible to place the device in the unwound state as a flat element in a dishwasher and thus to subject it to automatic cleaning with household appliances.

A compact transport state is understood, on the one hand, to mean, in particular, a rolled-up state which can be produced by rolling a flexible, flat element as closely as possible into the form of a compact roll, in particular in such a way that the rolled-up one Mouth and nose protection can be inserted into the pocket of a jacket or pants when it is not needed.

On the other hand, a compact state is understood to mean, in particular, a flat, folded state which can be produced by folding a foldable material, in particular in such a way that the folded mouth-nose protection can be inserted into the pocket of a jacket or trousers when it is not required.

A mouth and nose protection according to the invention thus makes it possible to provide a face-protecting infection protection by means of a cut from transparent material, which protection can be produced inexpensively and with which it is also possible to effectively prevent droplets or other particles from entering from the side or from behind reach the area between the mouth-nose protection and the mouth-nose area of the wearer. Infection protection which is independent of an additional mask can thus be achieved, which considerably increases the quality of interpersonal life in times when a mask is required, as the gestures and facial expressions of the wearer of an inventive mouth and nose protection are completely or at least largely preserved stay. Furthermore, a mouth and nose protection according to the invention can be cleaned from the outside during wear.

As already mentioned above, the size and shape of the cut and the at least one connecting element are preferably selected such that the use state enables the head of a human user to be completely enclosed horizontally in the region of the eyes, nose and mouth, i.e. there is a circumferential angle of 360 degrees.

The manufacture and use of a mouth and nose protection according to the invention is particularly simple if the blank is a one-piece element made of a flexible material. In this case, suitable transparent material only has to be brought into a specific product shape, in particular by material trimming, and equipped with the other technical features, in particular with at least one connecting element.

For the possibility already explained above of bringing the mouth-nose protection into a rolled-up transport state, it is particularly preferred if the blank is a one-piece element made of a rollable material.

As an alternative or in addition to this, the blank of a mouth-nose protection according to the invention can also be formed from an element which can be folded one or more times, for example from a transparent blank which has a plurality of fold regions. Such folding areas can be formed in particular in the manner of a film hinge. Mouth-nose guards are particularly suitable as a geometric shape for multiply foldable elements, which, when in use, form a head covering with a triangular, square, pentagonal, hexagonal, seven-sided or octagonal product geometry.

Depending on the embodiment of a mouth-nose protection according to the invention, the blank is preferably rolled up in the transport state, completely unfolded or folded one or more times. Regardless of the embodiment, it is preferred if the mouth-nose protection can be brought into a size in the transport state that enables the unnecessary mouth-nose protection to be inserted into a pocket of a garment in such a way that it is used for standard activities such as Walking, sitting, lying in it safely remains. The preferred maximum size of a mouth and nose protection according to the invention in the rolled-up transport state is approximately 40 cm with a maximum diameter of 8 cm, preferably 35 cm with a maximum diameter of 6 cm or 30 cm with a maximum diameter of 5 cm.

In a practical embodiment of a mouth-nose protection according to the invention, the blank has the basic shape of a truncated cone development or cylinder development. In this context, “basic shape” means that the mouth-nose protection is designed in such a way that it has a cylindrical, a truncated cone-shaped or a similar shape in the intended use state, in particular a shape that tapers from bottom to top and one has a round cross-sectional shape, ie has no edges (discontinuities) in a horizontal sectional view.

• - die obere Konturlinie der Kegelstumpfabwicklung durch eine lineare obere Konturlinie ersetzt ist,
• - die untere Konturlinie zwei bogenförmige Ausnehmungen aufweist, die im Nutzzustand ungefähr gegenüberliegend angeordnet sind,
• - die rechte Konturlinie und die linke Konturlinie jeweils mindestens eine Ausnehmung aufweist, die sich im Nutzzustand zu einer Durchgangsöffnung ergänzen, und/oder
• - im Bereich mindestens einer seitlichen Konturlinie ein Vorsprung und/oder ein Verbindungselement vorgesehen ist.

It has proven to be particularly suitable if the blank has a modified truncated cone development, the modification in particularly preferred variants being that

• - The upper contour line of the truncated cone is replaced by a linear upper contour line,
• the lower contour line has two arcuate recesses which are arranged approximately opposite one another in the use state,
• the right contour line and the left contour line each have at least one recess which, when in use, add up to form a through opening, and or
• - A projection and / or a connecting element is provided in the area of at least one lateral contour line.

By replacing the upper contour line of the truncated cone development with a linear upper contour line, the tilting stability of an inventive mouth and nose protector can be increased. This is achieved in that the upper contact area of the mouth-nose guard is shifted from a central area to the rear by this modification, as a result of which an overall approximately horizontal positioning of the mouth-nose guard on the head of a user can be achieved.

If the lower contour line has two arcuate recesses which are arranged approximately opposite one another in the use state, these recesses are preferably selected such that the mouth-nose protection can sit in an arc on the shoulders of a wearer. This also increases the stability against tipping and also improves the wearing comfort, since the weight of the mouth-nose protection is at least partially or even completely supported on the shoulders of the wearer. A particular advantage arises when the weight of the mouth-nose protection is fully supported on the shoulders, in particular if this enables the head to be turned freely because the head covering allows sufficient scope or space for the head to be turned and for positioning and fixation of the mouth-nose protection on the shoulders is realized.

If the right contour line and the left contour line each have at least one recess, which complement one another in the use state to form a through opening, a rear through opening can be produced in a simple manner. With such a through opening, both the acoustics and the ventilation within a mouth-nose guard can be improved in the use state. In this respect, such a passage opening can also be referred to as a hearing opening. Optionally, the recesses or the through opening resulting from the recesses can be equipped with a membrane in order to counter an unhindered rear penetration of particles or droplets or to reliably prevent this.

The blank according to the invention is preferably made from one of the materials acrylic glass, A-PET, hard PVC, Makrolon, PET-G, Plexiglas® or polycarbonate. These materials are available transparently in low material thickness, with low weight and in a flexible design and can also be processed easily and inexpensively. Furthermore, if a sufficiently large material thickness is selected, these materials have a certain inherent rigidity, which is advantageous for a dimensionally stable use condition.

At least one element of a Velcro fastener, a plug connection, a clip connection, a magnetic connection, an adhesive connection, a push button, a positive connection is particularly suitable as a connecting element, which can be formed or arranged simply or multiple times on the blank. Preferably, at least two complementary connecting elements are provided, for example two interacting Velcro elements, two interacting push-button elements, one or two through-openings for using a band or other separate connecting elements or integrally formed on the blank.

With regard to the above-mentioned interlocking connections, reference is made in particular to the possibility of forming cutouts and projections on a blank such that one or more projections come into engagement with one or more cutouts by utilizing the bending elasticity in the use state, and so there is a positive connection by means of which the blank can be fixed in a state in which it can envelop the head of a wearer, in particular by placing it on the head from above.

In a further practical embodiment of a mouth-nose protection according to the invention, at least one through opening and / or recess is provided in the blank, which can be produced, for example, by cutting or punching out. The formation of two through openings can be advantageous, in particular, in a position approximately opposite in the use state, for example such that the through openings lie in the area of the ears of the wearer when the mouth-nose guard is worn. In this case, the through openings can also be referred to as listening openings, since they serve to improve the acoustics for the wearer.

With regard to the size of the through openings serving in particular as a hearing opening, reference is made to those with a maximum diameter of 50 mm, in particular to through openings with a diameter between 10 mm and 40 mm, preferably to a diameter between 15 mm and 30 mm.

If arcuate recesses are provided for the shoulders of the wearer, such through-openings serving as hearing openings are preferably located in the area above these recesses.

The safety of a mouth and nose protection according to the invention with through openings serving as a hearing opening and for other purposes can be further increased if at least one membrane and / or a cover element is arranged in the at least one through opening. In this case, flexible and / or multi-part membranes and cover elements are particularly suitable, especially if the mouth-nose protection should be able to be rolled up as compactly as possible in the transport state.

If the cut of a mouth-nose guard has a geometry that tapers from bottom to top when in use, this can be designed in such a way that the mouth-nose guard sits on the head when in use. Then the tapered geometry is designed in such a way that the blank sits at least partially in the area of the top of a human head when in use, so that a part of its own weight is supported over the head of the user during use. This is particularly advantageous if the mouth-nose protection has a weight that is higher than 100 g, 200 g, or 250 g. In this case, the comfort can be increased by distributing the weight on the head and shoulders.

However, it is also possible to design the geometry in such a way that the blank, when in use, sits completely in the area of the top of a human head. In this case, recesses for the shoulders can be omitted.

In a further practical embodiment of a mouth-nose protection according to the invention, a bracket or band is provided in the blank as a positioning element. Such a band or such a hanger can be designed to be adjustable, so that the mouth-nose protection can be adapted to the shape and size of most or all of the wearers.

With regard to the length of the blank in the development, reference is made in particular to lengths between 700 mm and 1000 mm, preferably 850 mm to 950 mm.

Regardless of this, the height of the blank in the development is preferably between 200 mm and 450 mm, more preferably between 250 mm and 400 mm.

In order to avoid injuries at corners, it is advantageous if the cut of a mouth-nose protection according to the invention has only rounded corners and edges.

In a further practical embodiment of a mouth-nose protection, a cover element covering the top of the head is provided, at least in the use state, which is connected or can be connected to the part of the blank enclosing the head. Such a cover element can also be referred to as the “cover” or “roof” of a mouth-nose guard, and it can thereby be predominantly or completely avoided that particles and / or droplets from the top into the area between the mouth-nose guard and Carrier arrive.

The blank preferably has the shape of a cylinder, a cone, a truncated cone, a pyramid or a truncated pyramid when in use. The maximum recess on the top side in the horizontal direction is preferably between 200 mm and 280 mm, particularly preferably between 240 mm and 260 mm. The underside maximum extension in the horizontal direction preferably extends between 260 mm and 320 mm, particularly preferably between 280 mm and 300 mm.

The total weight of a mouth-nose protection according to the invention is preferably less than 200 g, particularly preferably a maximum of 150 g and further preferably a maximum of 120 g or a maximum of 100 g.

The material thickness of the material from which the blank is formed is preferably at most 1 mm, preferably at most 0.6 mm, more preferably at most 0.5 mm and particularly preferably at most 0.3 mm. Preferred value ranges are between 0.2 mm and 0.6 mm.

The mouth and nose protection according to the invention is preferably designed as all-round protection, i.e. extends over the full circumference of the head of a person wearing it.

As an alternative or in addition to this, the cut is designed in such a way that the mouth-nose protection extends in the use state in the area of the front of a person carrying it to a level below the shoulders, in particular up to the upper area of the chest. In this case, there are particular advantages if the mouth and nose protection according to the invention is designed such that it is supported on the shoulders of a person wearing it, so that head movements can be carried out independently of the positioning of the mouth and nose protection.

• 1 eine modifizierte Kegelstumpfabwicklung für eine erste Ausführungsform eines erfindungsgemäßen Mund-Nasen-Schutzes,
• 2 eine andere modifizierte Kegelstumpfabwicklung für eine zweite Ausführungsform eines erfindungsgemäßen Mund-Nasen-Schutzes,
• 3 eine andere modifizierte Kegelstumpfabwicklung für eine dritte Ausführungsform eines erfindungsgemäßen Mund-Nasen-Schutzes,
• 4 ein zusammenrollbarer Mund-Nasen-Schutz im zusammengerollten Transportzustand und
• 5 den Mund-Nasen-Schutz gemäß 1 im Nutzzustand,
• 6 den Mund-Nasen-Schutz gemäß 3 im Nutzzustand und
• 7 eine andere modifizierte Kegelstumpfabwicklung für eine vierte Ausführungsform eines erfindungsgemäßen Mund-Nasen-Schutzes.

Further practical embodiments of the invention are described below in connection with the drawings. Show it:

• 1 a modified truncated cone development for a first embodiment of a mouth-nose protection according to the invention,
• 2nd another modified truncated cone development for a second embodiment of a mouth-nose protection according to the invention,
• 3rd another modified truncated cone development for a third embodiment of a mouth-nose protection according to the invention,
• 4th a roll-up mouth-nose protection when rolled up and
• 5 according to the mouth-nose protection 1 in use,
• 6 according to the mouth-nose protection 3rd in use and
• 7 another modified truncated cone development for a fourth embodiment of a mouth-nose protection according to the invention.

In the 1 to 6 are different states of three different embodiments of mouth and nose protectors according to the invention 10 shown. For clarification, it is pointed out in advance that the same reference numerals are used to describe all embodiments in all figures for identical or at least functionally identical elements.

In the 1 to 3rd are three blanks 12th the three different embodiments in the developed state (processing) shown in comparison. In all cases, these are blanks 12th made of a transparent material that is flexible and that - like in 4th shown - can be brought into a rolled-up transport state. In the present case, plexiglass was used as the material. Each of the blanks 12th can be easily and inexpensively produced from a sufficiently large plexiglass element by simply cutting it out, for example using a plotter.

Now the in 1 shown blank 12th described in detail. Then follow the descriptions of the blanks 12th according to the 2nd and 3rd , in the description of which the differences compared to the previously described embodiments are discussed.

The in 1 shown blank has an upper contour line 14 on, which is arcuate. On the upper contour line 14 close a left contour line 16 and a right contour line 18th which have a linear course. The lower ends of the left contour line 16 and the right contour line 18th are over a lower contour line 20 connected, which in turn has an arcuate course and has essentially the same curvature as the upper contour line 16 . In the 1 shown contour lines 14 , 16 , 18th , 20 correspond to the contour lines of a truncated cone development, the left contour line 16 through an upper arcuate projection 22 and a lower arcuate protrusion 24th is interrupted and the right contour line 18th through an upper arcuate projection 26 and a lower arcuate protrusion 28 is interrupted. In the area of these arcuate projections 22 , 24th , 26 , 28 are as fasteners 30th Velcro elements 32 arranged.

The lower contour line 20 is through a left arcuate recess 34 and a right arcuate recess 36 interrupted. These recesses 34 , 36 are dimensioned so that the cut is in the 5 shown transport condition on the shoulders of a mouth-nose protection 10 carrying person 38 can support.

Above the recesses 34 , 36 are within the cut 12th through openings serving as listening openings 40 , 42 trained in the use state in the ears of the person wearing the mouth and nose protection 28 are arranged (cf. 5 ).

In the 2nd The embodiment shown differs in particular from that in FIG 1 illustrated embodiment that the upper contour line 14 is linear. With the help of experiments it was found that the relative orientation and the stability of the mouth-nose protection 10 to the head of a person carrying it 38 is improved because of the protection of the mouth and nose 10 in this case there is less tendency to tip forward.

In the 3rd The embodiment shown differs in particular from that in FIG 2nd illustrated embodiment that the lower contour line 20 only between the recesses 34 , 36 extends. In the remaining areas between the lower end of the left contour line 16 and the left recess 34 is a modified lower contour line 44 and in the area between the lower end of the right contour line 18th and the right recess 36 is a modified lower contour line 46 trained, which is at a higher level than the lower contour line 46 , but has approximately the same curvature. This results in wearing the nose and throat protection 10 in the usage state in the area behind the shoulders a lower edge that is at a higher level than the front lower edge. This facilitates the free rotation of the head and, moreover, at least to a certain extent also allows the head to pitch, without this leading to significant relative movements between mouth and nose protection 10 and head of the person carrying it 28 is coming.

Another difference in 3rd embodiment shown is that the left contour line 16 and the right contour line 18th are not interrupted. As fasteners 30th are on the contour lines in this embodiment 16 , 18th two push buttons adjoining each 48 intended.

Like from the 1 to 3rd it can be seen that the construction of the mouth-nose protectors according to the invention is very simple, because these essentially consist of one blank each 12th a suitable, flexible, transparent material and on these blanks 12th arranged connecting elements 30th .

7 shows a modified truncated cone development for a fourth embodiment of a mouth-nose protection according to the invention. This is based on the truncated cone development 2nd and differs from this embodiment in particular in that instead of the through openings provided in the figure 40 , 42 in the blank 12th in the area of the left contour line 16 and the right contour line 18th recesses each 50 , 52 are provided in such a way that, when in use, there is a large through opening (not shown) on the back, by means of which the acoustics and ventilation of the mouth and nose protection 10 is improved. This through opening can optionally be provided with a membrane in order to prevent the unimpeded penetration of particles and droplets.

The features of the invention disclosed in the present description, in the drawings and in the claims can be essential both individually and in any combination for realizing the invention in its various embodiments. The invention can be varied within the scope of the claims and taking into account the knowledge of the person skilled in the art.

In particular, reference is once again made to the fact that instead of the in 1 to 3rd shown separate connecting elements 30th in the form of Velcro elements 32 or push buttons 48 also connecting elements (not shown) with the help of the blank 12th by appropriate shaping of the cut 12th can be formed on this itself. In this regard, reference is made in particular to the possibility of one or more tabs (not shown) which project in the manner of a cantilever arm in the region of a lateral contour line 16 , 18th form, which cooperate with complementary recesses (not shown), which are formed in the area of the other lateral contour line.

Reference list

10th

Mouth-nose protection

12th

Cutting

14

upper contour line

16

left contour line

18th

right contour line

20

lower contour line

22

arcuate projection

24th

arcuate projection

26

arcuate projection

28

arcuate projection

30th

Fastener

32

Velcro element

34

Recess

36

Recess

38

person

40

Through opening

42

Through opening

44

modified lower contour line

46

modified lower contour line

48

Push button

50

Recess

52

Recess

Claims (19)

Mouth-nose protection (10) in the form of a blank (12) made of bendable and / or foldable, transparent material, on which at least one connecting element (30) is provided, the blank (12) and the connecting element (30) being such are designed so that the blank (12) can be brought from a compact transport state into a usable state suitable for the head covering, the size and shape of the blank (12) and the at least one connecting element (30) being selected such that the blank ( 12) can be temporarily fixed in the use state with the aid of the connecting element (30), the use state allowing an at least predominant horizontal encirclement of the head of a human user in the area of the eyes, nose and mouth. Mouth-nose protection (10) according to the preceding claim, characterized in that the size and shape of the blank (12) and the at least one connecting element (30) are selected in such a way that the state of use completely encloses the head of a human user horizontally in the area of the eyes, nose and mouth. Mouth-nose protection (10) according to any one of the preceding claims, characterized in that the blank (12) is a one-piece element made of a flexible material. Mouth-nose protection (10) according to the preceding claim, characterized in that the blank (12) is a one-piece element made of a rollable material. Mouth-nose protection (10) according to one of the preceding claims, characterized in that the blank (12) is formed from a single or multiple foldable element. Mouth-nose protection (10) according to any one of the preceding claims, characterized in that the blank (12) is rolled up in the transport state, completely unfolded or folded one or more times. Mouth-nose protection (10) according to one of the preceding claims, characterized in that the blank (12) has the basic shape of a truncated cone development or cylinder development. Mouth-nose protection (10) according to one of the preceding claims, characterized in that the blank (12) has a modified truncated cone development, the modification consisting in that a) the upper contour line (14) of the truncated cone development by a linear upper contour line (14) is replaced, b) the lower contour line (20) has two arcuate recesses (34, 36) which are arranged approximately opposite one another in the use state, c) the right contour line (18) and the left contour line (16) each have at least one Has recess (34, 36), which complement each other to form a through opening (40, 42), and / or d) a projection or a connecting element (30) is provided in the region of at least one lateral contour line. Mouth-nose protection (10) according to one of the preceding claims, characterized in that the blank (12) is made from one of the materials acrylic glass, A-PET, hard PVC, macroion, PET-G, Plexiglas® or polycarbonate. Mouth-nose protection (10) according to one of the preceding claims, characterized in that at least one connecting element (30) is an element of a Velcro fastener, a plug connection, a clip connection, a magnetic connection, an adhesive connection, a push button (48), one Form-fit connection is. Mouth-nose protection (10) according to one of the preceding claims, characterized in that at least one through opening (40, 42) and / or recess (34, 36, 50, 52) is provided in the blank (12). Mouth-nose protection (10) according to the preceding claim, characterized in that at least one membrane and / or a cover element is arranged in the at least one through opening (40, 42). Mouth-nose protection (10) according to one of the preceding claims, characterized in that the blank (12) has a geometry which tapers from bottom to top when in use. Mouth-nose protection (10) according to the preceding claim, characterized in that the tapered geometry is designed such that the blank (12) sits at least partially in the use state in the region of the top of a human head, so that part of the Own weight is supported over the head of the user during use. Mouth-nose protection (10) according to one of the preceding claims, characterized in that a bracket or band is provided as a positioning element in the blank (12). Mouth-nose protection (10) according to one of the preceding claims, characterized in that the length of the blank (12) in the development is between 700 mm and 1000 mm and / or the height of the blank (12) in the development between 200 mm and 450 mm. Mouth-nose protection (10) according to one of the preceding claims, characterized in that the blank (12) has only rounded corners and edges. Mouth-nose protection (10) according to one of the preceding claims, characterized in that a cover element covering the top of the head is provided at least in the use state, which is connected or connectable to the part of the blank (12) surrounding the head. Mouth-nose protection (10) according to one of the preceding claims, characterized in that that the blank (12) has the shape of a cylinder, a cone, a truncated cone, a pyramid or a truncated pyramid when in use.

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