FIELD OF THE INVENTION
[0001] The present invention concerns a solar covering apparatus, such as a pergola or other
structure for outdoor spaces, with a covering and protection function, intended for
civil use, mainly supplementary to residential areas, but also commercial, public
or for exhibitions.
[0002] The pergola is provided with an upper structure with which covering elements cooperate,
which generally determine a desired condition of direct or indirect irradiation, that
is, of passage of air, light and water, in the area below the upper structure.
BACKGROUND OF THE INVENTION
[0003] A pergola type covering apparatus is known, which typically comprises a lower support
structure, formed by a plurality of structural support vertical elements, also called
uprights, which are able to sustain, at a certain height from the floor or from the
ground, an upper structure having the shape of a complete, or partial, quadrangular
frame. This upper structure normally consists of sustaining elements, typically horizontal
or moderately inclined in the order of 5°-20° with respect to the plane of the floor,
also called uprights.
[0004] Usually, there is provided a pair of lateral uprights, which act as a support for
the covering elements, and a pair of uprights, one at the head and one at the tail,
perpendicular to the lateral uprights. The lateral uprights define a longitudinal
direction in which corresponding covering elements can move.
[0005] In fact, it is known that covering elements, or slats, are operatively associated
with the upper structure, which are advantageously mobile with respect to each other
in order to define at least one closing operating condition that corresponds to a
covering condition, in which they are all substantially coplanar with each other and
reciprocally contact each other to define an actual "roof' of the structure, and a
plurality of opening conditions, which correspond to respective uncovering conditions,
in which they are disposed in such a way as to define corresponding compartments,
more or less wide, for the passage of light and/or air or other atmospheric agents.
These solutions allow to modulate the intensity and power of the light and/or air
to be allowed to enter into the pergola.
[0006] Among the various solutions for the reciprocal movement of the slats, for example
with rotation, with packing, or others, solutions are known in which there is a relative
movement between two groups of slats, so that they assume at least a substantially
offset covering condition and at least a partly stacked condition of passage of light
and air. A covering apparatus with such a movement system is described in document
EP 1 307 621 B1.
[0007] In addition, the slats of each group usually have predefined sizes and are disposed
at a certain pitch from each other so that, as a function of the total number of slats
provided, they determine the capacity to cover a certain width, understood as their
size parallel to the longitudinal direction, when they are installed in the bearing
structure.
[0008] One of the disadvantages of current covering apparatuses is that the internal length
of the support structure, defined by the distance between the two head and tail uprights,
has to always be a multiple of the width of the slats, or of the aforementioned pitch.
Otherwise, the overall extension of the slats is smaller than the underlying area
to be protected, leaving some parts uncovered, in particular when they are in the
covering position.
[0009] In the solutions with two groups of reciprocally mobile slats, to compensate for
the uncovered parts, specific designs and resizing of the slats themselves are required,
in relation to the sizes in length of the structure, at the expense of design and
construction times and costs, which necessarily have to be focused for each type of
pergola.
[0010] This disadvantageous situation also requires having different types of slats ready
in stock, both in terms of size as well as structure, with a further increase in production
costs.
[0011] In addition, by modifying the sizes of the slats, different modes for their relative
movement are required, in order to prevent malfunctions or unexpected interferences.
This aspect also generates unwanted production times and costs.
[0012] Document
JP 2017096090 A describes furnishings such as doors and dividers that separate two spaces, but are
in any case able to allow or block the circulation of air through a system of mobile
slats with guillotine-like movement.
[0013] There is therefore the need to provide a covering apparatus that can overcome at
least one of the disadvantages of the state of the art.
[0014] One purpose of the present invention is to provide a covering apparatus provided
with two groups of covering elements relatively mobile with respect to each other,
in which any free space that were to be created between a terminal covering element
and the corresponding upright of the support structure can be covered in a stable
and safe manner, without needing to provide for specific designs and productions of
the covering elements, and without interferences being generated, or other problems
arising, with the movement of the covering elements.
[0015] Another purpose of the present invention is to provide a covering apparatus provided
with mobile covering elements in which any free space between the terminal covering
element and the corresponding upright can be compensated in a simple and effective
manner.
[0016] The Applicant has devised, tested and embodied the present invention to overcome
the shortcomings of the state of the art and to obtain these and other purposes and
advantages.
SUMMARY OF THE INVENTION
[0017] The present invention is set forth and characterized in the independent claim. The
dependent claims describe other characteristics of the present invention or variants
to the main inventive idea.
[0018] In accordance with the above purposes, a covering apparatus according to the present
invention is of the type comprising at least one upper structure having a length defined
between two substantially horizontal head sustaining elements, or uprights, thereof.
The head sustaining elements are part of the upper structure.
[0019] The covering apparatus also comprises a plurality of first covering elements, or
fixed slats, assembled with a certain pitch on the upper structure, and a correlated
plurality of second covering elements, or mobile slats, which can be moved selectively
with respect to the fixed slats.
[0020] In particular, this selective movement allows for different reciprocal positionings
between the fixed slats and the mobile slats, so as to define at least one opening
condition in which there are defined desired direct or indirect passages of light
and/or air through the upper structure, and one covering condition in which each mobile
slat is disposed offset with respect to each fixed slat and defines at least one overlap
portion with at least one of the adjacent fixed slats. In this covering condition,
the reciprocal positioning of the fixed slats and the mobile slats, as described,
substantially prevents the passage of light and/or air through the upper structure.
[0021] In accordance with one aspect of the present invention, a summation calculated between
the overlap portions is at least equal to a difference calculated between the length
of the upper structure and a covering size defined between a first and a last fixed
slat.
[0022] In other words, the covering size represents an imaginary surface delimited on at
least two sides by the first and the last of the first covering elements or fixed
slats.
[0023] In mathematical terms, we therefore have that ∑
(nOP) =
Δ(L-CD), in which "nOP" is the number of overlap portions, "L" is the length of the upper
structure and "CD" is the covering size defined by the fixed slats.
[0024] In other words, the sum of all the overlap portions that are defined in the covering
condition is at least equal to the size to be compensated, in order to define the
complete closure of the upper structure.
[0025] In this way, it is possible to exploit the logic of this equation to modify the extent
of each overlap, in order to compensate for the difference between length and covering
size. In fact, by varying the size of the overlap, acting practically on the pitch
of the fixed blades, it is possible to increase the covering size, until the entire
length of the upper structure is filled and, at the same time, keep the sizes of both
the fixed blades as well as the mobile blades unchanged.
[0026] With the solution according to the present invention there is therefore the possibility
of reciprocally modifying the position of the fixed blades, without the need to provide
specific designs and productions of the covering elements, and without generating
interferences, or causing other problems, with the movement of the latter.
[0027] Furthermore, the redefinition of the pitches of the fixed blades, starting from a
predetermined lay-out functional to the uncovered parts to be filled, is industrially
easy and economical to create.
[0028] Moreover, since the initial disposition of the fixed and mobile slats is achieved
based on a defined mathematical relationship, it is even more effective and economical
to predetermine any functional work for attaching the fixed slats onto the uprights,
also to the advantage of an effective functional repeatability of the slats, independently
of the upper structure's sizes in width.
[0029] According to another aspect of the present invention, the value of the summation
of the overlaps can be larger than the difference between the length of the upper
structure and the covering size of the fixed slats by a value of the order of centimeters.
[0030] This advantageous solution allows to keep a certain margin of overlap between the
fixed slats and the mobile slats, guaranteeing in any case that the length of the
upper structure is covered entirely.
[0031] According to another aspect of the present invention, each overlap portion is equal
to the ratio between said difference and the number of the overlap portions to define
the complete closure of the upper structure.
[0032] According to another aspect of the present invention, the upper structure also comprises
two lateral sustaining elements to which the plurality of first covering elements
is attached, and with which the plurality of second covering elements is associated
sliding.
[0033] According to one embodiment of the present invention, the first and the last of the
first covering elements can be disposed in direct cooperation with respective ones
of the head sustaining elements.
[0034] According to another aspect of the present invention, there can be provided at least
one compensation device, attached to at least one of either the first or the last
of the first covering elements. Advantageously, the compensation device is disposed
in cooperation with at least one of the sustaining elements, so as to compensate for
the possible additional distance between the corresponding covering element and the
corresponding sustaining element.
[0035] This advantageous solution allows to further simplify the compensation of the distance
that can exist between the sustaining elements and the fixed slats.
[0036] In fact, by using the compensation device, it is possible to reduce the conditions
of modification of the pitch of the fixed slats, to the advantage of a simpler assembly
of the pergola, in particular in conditions whereby the length of the support structure
is different from an integer multiple of the pitch of the fixed slats.
[0037] Moreover, the cooperation between the modification of the pitch and the compensation
device allows to substantially standardize the sizes and positioning of the latter,
as an additional advantage of the simplification and the reduction of the costs for
setting up the pergola, essentially whatever the support structure's sizes in length.
[0038] According to one aspect of the present invention, in which the sustaining element
is associated at least with a water outflow element, such as a gutter for example,
the compensation device is positioned and conformed in order to at least partly overlap
with the water outflow element. In this way, in addition to defining a substantial
aesthetic continuity up to the gutter, it is at least partly possible to manage any
rainwater, directing it toward the gutter and limiting the possibility of any dripping
toward the zone below the support structure to a minimum.
[0039] According to another aspect of the present invention, in which the fixed slats define
at least one covering plane, the compensation device is disposed substantially coplanar
with such covering plane, so as to not aesthetically impact the pergola's design.
[0040] According to another aspect of the present invention, the compensation device comprises
at least one covering body that has at least one edge facing toward the closest sustaining
element.
[0041] Advantageously, this edge is distant from the corresponding fixed slat by a measure
smaller than the distance between the fixed slat itself and the corresponding sustaining
element. Furthermore, the edge is disposed above the water outflow element, so as
to further improve the conditions for managing the water and its outflow toward the
gutter.
[0042] According to another aspect of the present invention, the compensation device comprises
attachment means, which are disposed in cooperation with the first or the last of
the fixed slats, in order to attach the latter to the covering body.
[0043] Advantageously, the attachment means can be of a substantially known type, whether
of the removable or irremovable type, without in any case departing from the spirit
of the inventive idea of the present invention.
[0044] According to another aspect of the present invention, there can be provided a compensation
device attached to the first fixed slat and a compensation device attached to the
last fixed slat, so as to have a condition of compensation that is substantially symmetrical
with respect to the support structure and thus define a condition in which the loads,
inertias and design lines are balanced.
[0045] According to one variant, the compensation device is attached to the support structure.
[0046] According to another variant, the compensation device is attached to the water outflow
element.
[0047] According to still other variants, the compensation device is freely attached between
the fixed slats, the support structure and/or the water outflow element.
[0048] Some embodiments of the present invention also concern a method for assembling a
covering apparatus comprising the assembly of at least one upper structure having
two head sustaining elements, the distance between them defining a length of the upper
structure, the assembly of a plurality of first covering elements to the upper structure,
and of a plurality of second covering elements which are mobile with respect to the
first covering elements, between at least one opening condition and one covering condition,
in which each of the second covering elements is disposed offset with respect to each
of the first covering elements and defines at least one overlap portion with at least
one first adjacent covering element.
[0049] According to the present invention, the method comprises assembling the plurality
of first covering elements and second covering elements in such a way that a summation
calculated between the overlap portions is at least equal to a difference calculated
between the length of the upper structure and a covering size defined between a first
and a last of the first covering elements.
DESCRIPTION OF THE DRAWINGS
[0050] These and other aspects, characteristics and advantages of the present invention
will become apparent from the following description of some embodiments, given as
a non-restrictive example with reference to the attached drawings wherein:
- fig. 1 shows a three-dimensional view of a covering apparatus according to the present
invention, in a first operating condition;
- fig. 2 shows a longitudinal section of the covering apparatus of fig. 1, in a first
embodiment, in a preliminary phase;
- fig. 3 shows a longitudinal section of the covering apparatus of fig. 1, in a first
embodiment, in an operational phase;
- fig. 4 shows a longitudinal section of the covering apparatus of fig. 1, in a second
embodiment;
- fig. 5 shows a longitudinal section of the covering apparatus of fig. 1, in a third
embodiment;
- fig. 6 schematically shows a detail of fig. 5.
[0051] To facilitate comprehension, the same reference numbers have been used, where possible,
to identify identical common elements in the drawings. It is understood that elements
and characteristics of one embodiment can be conveniently combined or incorporated
into other embodiments without further clarifications.
DESCRIPTION OF SOME EMBODIMENTS
[0052] We will now refer in detail to the possible embodiments of the invention, of which
one or more examples are shown in the attached drawings, by way of a non-limiting
illustration. The phraseology and terminology used here is also for the purposes of
providing non-limiting examples.
[0053] The attached drawings concern a covering apparatus, in this specific case a pergola
10 for outdoor spaces.
[0054] The pergola 10 typically comprises, and is defined by, four vertical uprights 11
conformed to keep an upper structure 12, also referred to hereafter as upper frame
12, in a desired raised condition.
[0055] The upper frame 12 is substantially formed by a pair of lateral sustaining elements,
or lateral uprights, 13a and by a pair of head sustaining elements, or head uprights,
13b associated with each other so as to give the upper frame 12 a substantially square
or rectangular conformation that delimits the zone to be covered at the upper part.
[0056] The pergola 10 further comprises a first group of slats 14, attached to the upper
frame 12, and a second group of slats 15, mobile with respect to the slats 14 of the
first group in a direction Z substantially longitudinal to the upper frame 12.
[0057] The slats 14 of the first group are fixed and, hereafter in the description, are
also referred to as first fixed slats 14. The slats 15 of the second group are mobile
and, hereafter in the description, are also referred to as second mobile slats 15.
[0058] In this way, the lateral uprights 13a are substantially parallel to each other and
to the direction Z, while the head uprights 13b are substantially parallel to each
other and orthogonal to the longitudinal direction Z.
[0059] The distance between the head uprights 13b defines a longitudinal length L of the
upper frame 12.
[0060] The fixed slats 14 are associated at their terminal ends with the lateral uprights
13a, in a condition substantially parallel to the head uprights 13b.
[0061] Each first slat 14 is distant from the adjacent first slat 14 by a certain pitch
P1. In this way, the set of first slats 14 spaced apart by the pitch P1 defines both
a covering plane CP and also a covering size CD.
[0062] The mobile slats 15 are disposed above and substantially parallel to the first fixed
slats 14, and are mounted with their terminal ends to corresponding movement guides
(of a substantially known type and not shown in detail).
[0063] The movement guides can be attached to the lateral uprights 13a.
[0064] The second slats 15 are also spaced apart from each other by a certain pitch P2.
[0065] The pitch P1 and the pitch P2 can be freely the same or different from each other.
[0066] The second slats 15, in a condition of coverage of the pergola 10, are offset with
respect to the first slats 14, in a position such that each second slat 15 defines
two overlap portions OP with two corresponding adjacent first slats 14.
[0067] It is not excluded, according to variants not shown, that the second slats 15 can
in any case be at a lower level than the first slats 14, that is, be taken, in some
operating conditions, into a condition of substantial coplanarity with the first slats
14. It is not excluded, moreover, that the second slats 15 can be kept in a fixed
position, and that it is the first slats 14 that move; it is also not excluded that
both first slats 14 can be moved, for example in opposite directions, or with different
speeds, or in different and combined movement conditions, always in order to define
the desired covering and opening conditions to prevent or define desired direct or
indirect passages of light and/or air.
[0068] With particular reference to figs. 2 and 3, the starting overlap portions OP have
a size whereby their summation is at least equal to the difference Δ between the length
L of the support frame 12 and the covering size CD defined by the first slats 14.
[0069] To give, purely by way of example, a numerical example in which the values used are
indicative and imaginary, if we have a length L equal to 145cm and a covering size
CD equal to 140cm, this results in a difference Δ of 5cm overall, in this specific
case equally divided into two portions Δ/2.
[0070] Therefore, respecting the equation characteristic of the present invention, we have
that each overlap portion OP has to be at least equal to the ratio between the difference
Δ and the number of such overlap portions which, in this specific case, based on the
number of first and second slats 14 and 15, their pitch P1 and P2 and their reciprocal
disposition, are in number of 6 (six).
[0071] Therefore, each overlap portion OP has to be at least equal to 5/6, that is, at least
approximately 0.8cm each.
[0072] This minimum size allows to compensate for the difference Δ, by varying the pitch
P1 and P2 of the first slats 14 and of the second slats 15, until the first end slats
14 are taken into contact with the lateral uprights 13a, as shown in the comparison
with fig. 3.
[0073] In this specific case, we must clarify that, although the difference Δ has been completely
compensated for, the second slats 15 still define an overlap portion OP which, in
this case, is functional for the management and effective drainage of rainwater or
wastewater on the slats 15 themselves.
[0074] This overlap between the second and first slats 15 and 14 is advantageously taken
into account as an additional value for the calculation of the minimum overlap portion
OP.
[0075] Advantageously, between each first terminal slat 14 and the corresponding head upright
13b, one or more hydraulic seal gaskets are provided (not shown in the drawings),
to prevent unwanted dripping and infiltrations between the upright 13b and the first
terminal slat 14 itself.
[0076] With reference to figs. 4, 5 and 6, at least along the head uprights 13b there are
provided corresponding water outflow elements, or gutters, 16, advantageously also
along the lateral uprights 13a, although not specifically shown in the attached drawings.
[0077] In the case of fig. 4, we have, as in the previously described embodiment, a covering
size CD defined by the first slats 14 and a length L defined, in this specific case,
by the distance between the gutters 16 and not between the head uprights 13b. This
logical variation is given by the fact that the gutters 16 partly reduce the useful
zone for the passage of air and light through the upper frame 12.
[0078] Again, as in the previous case, the summation of the overlap portions OP which are
defined between the second slats 15 and the first slats 14 has to be at least equal
to the difference between the length L and the covering size CD.
[0079] Advantageously, since a hydraulic drainage management gutter 16 is provided, it is
particularly effective to provide a partial overlap also between the first terminal
slats 14 and the corresponding gutters 16, in order to prevent both unwanted splashes
and dripping, as well as the use of complex gasket systems. This overlap between the
first slats 14 and the gutters 16 is advantageously taken into account as an additional
value for the calculation of the minimum overlap portion OP between the second slats
15 and the first slats 14.
[0080] In the advantageous embodiment shown in figs. 5 and 6, a corresponding compensation
profile or device 17 is associated with each of the first terminal slats 14. The compensation
device 17 substantially has the function of increasing, by a predetermined proportion,
the covering size CD, in a manner substantially independent of the conformation, number
and pitch P1 of the first slats 14.
[0081] The compensation profile 17 can have an "L" shape.
[0082] In particular, the compensation profile 17 comprises at least one covering body 18,
the latter being provided with an edge 19 facing, during use, toward the corresponding
head upright 13b.
[0083] The size of the covering body 18 is such that the edge 19 is distanced away from
the corresponding first slat 14 by a measure M smaller than the distance D between
the first slat 14 itself and the corresponding head upright 13b.
[0084] In this way, the edge 19 is advantageously disposed above the gutter 16, to the obvious
advantage of managing the outflow of rainwater and wastewater.
[0085] According to some variants, not shown, the covering body 18 can have a section tapered
toward the edge 19, so as to facilitate the conditions of outflow of the water toward
the gutter 16.
[0086] In the same way, the tapered conformation of the section of the covering body 18
can have a lower surface with a flat development, so that it can be disposed in continuity
with a corresponding lower surface of the corresponding first slat 14 and, therefore,
define a single covering plane CP.
[0087] The compensation profile 17 also comprises attachment devices 20 (of a substantially
known type and not shown in detail in the drawings), by means of which the covering
body 18 is disposed in stable and effective cooperation with the corresponding first
slat 14, for example in substantial continuity with a lower surface of the latter
in order to define, as stated, a single covering plane CP.
[0088] According to some variants of the present invention, the attachment devices 20 can
provide coupling, snap-in or same-shape attachment systems, or systems for attachment
by means of screw elements or other, without thereby departing from the scope of the
present invention.
[0089] With the use of the compensation profile 17, it is possible to further simplify the
operations for calculating the overlap portion OP to be obtained between the second
slats 15 and the first slats 14, as well as the corresponding variations of pitch
P1 and P2 on which to intervene in order to compensate for the difference Δ.
[0090] In fact, by knowing the measure M of the covering body 18 a priori, it is possible
to calculate ranges of values for the overlap portion OP between the second slats
15 and the first slats 14, the ranges being valid for different lengths L of the support
frame 12, limiting to a minimum, if not eliminating, the necessary variations of pitch
P1 and P2 required to compensate for the difference Δ.
[0091] It is clear that modifications and/or additions of parts or steps may be made to
the covering apparatus 10 as described heretofore, without departing from the field
and scope of the present invention, as defined by the claims.
[0092] In the following claims, the sole purpose of the references in brackets is to facilitate
reading and they must not be considered as restrictive factors with regard to the
field of protection defined in the specific claims.
1. Covering apparatus (10) comprising at least one upper structure (12) having two head
sustaining elements (13b), the distance between them defining a length (L) of said
upper structure (12), a plurality of first covering elements (14) attached to said
upper structure (12), and a plurality of second covering elements (15) mobile with
respect to said first covering elements (14) between at least one opening condition
and one covering condition, in which each of said second covering elements (15) is
disposed offset with respect to each of said first covering elements (14) and defines
at least one overlap portion (OP) with at least one first adjacent covering element
(14), characterized in that a summation (Σ) calculated between said overlap portions (OP) is at least equal to
a difference (Δ) calculated between said length (L) of said upper structure (12) and
a covering size (CD) defined between a first and a last of said first covering elements
(14).
2. Covering apparatus (10) as in claim 1, characterized in that the value of said summation (Σ) is larger than said difference (Δ) by a value of
the order of centimeters.
3. Covering apparatus (10) as in claim 1 or 2, characterized in that each overlap portion (OP) is equal to the ratio between said difference (Δ) and the
number of said overlap portions (OP) to define the complete closure of said upper
structure (12).
4. Covering apparatus (10) as in one or the other of the previous claims, characterized in that said upper structure (12) also comprises two lateral sustaining elements (13a) to
which said plurality of first covering elements (14) is attached and with which said
plurality of second covering elements (15) is associated sliding.
5. Covering apparatus (10) as in one or the other of the previous claims, characterized in that said first and said last of said first covering elements (14) are disposed in direct
cooperation with respective ones of said head sustaining elements (13b).
6. Covering apparatus (10) as in one or the other of claims from 1 to 4, characterized in that it comprises at least one compensation device (17) attached to at least one of either
said first or said last of said first covering elements (14) and disposed in cooperation
with at least one of said head sustaining elements (13b).
7. Covering apparatus (10) as in claim 6, wherein said at least one of said head sustaining
elements (13b) is associated with at least one water outflow element (16), characterized in that said compensation device (17) at least partly overlaps said water outflow element
(16).
8. Covering apparatus (10) as in one or the other of the previous claims from 6 onward,
wherein said first covering elements (14) define at least one covering plane (CP),
characterized in that said compensation device (17) is disposed substantially coplanar with said covering
plane (CP).
9. Covering apparatus (10) as in one or the other of the previous claims from 6 onward,
characterized in that said compensation device (17) comprises at least one covering body (18) that has
at least one edge (19) facing toward said at least one of said head sustaining elements
(13b).
10. Covering apparatus (10) as in claim 9, characterized in that said edge (19) is distant from said first covering element (14) by a measure (M)
smaller than the distance (D) between said first covering element (14) and the corresponding
head sustaining element (13b).
11. Covering apparatus (10) as in claims 7 and 9, characterized in that said edge (18) is disposed above said water outflow element (16).
12. Covering apparatus (10) as in one or the other of the previous claims from 9 onward,
characterized in that said compensation device (17) comprises attachment means (20) disposed in cooperation
with said first or said last of said first covering elements (14) in order to attach
said covering body (18) to the latter.
13. Covering apparatus (10) as in one or the other of the previous claims from 6 onward,
characterized in that it comprises a compensation device (17) attached to said first of said first covering
elements (14) and a compensation device (17) attached to said last of said first covering
elements (14).
14. Method for assembling a covering apparatus (10), comprising the assembly of at least
one upper structure (12) having two head sustaining elements (13b), the distance between
them defining a length (L) of said upper structure (12), of a plurality of first covering
elements (14) to said upper structure (12), and of a plurality of second covering
elements (15) which are mobile with respect to said first covering elements (14),
between at least one opening condition and one covering condition, in which each of
said second covering elements (15) is disposed offset with respect to each of said
first covering elements (14) and defines at least one overlap portion (OP) with at
least one first adjacent covering element (14), characterized in that said method comprises assembling said plurality of first covering elements (14) and
second covering elements (15) in such a way that a summation (Σ) calculated between
said overlap portions (OP) is at least equal to a difference (Δ) calculated between
said length (L) of said upper structure (12) and a covering size (CD) defined between
a first and a last of said first covering elements (14).