TECHNICAL FIELD

The disclosure relates to a hinge assembly for a foldable apparatus, the hinge assembly being moveable between a closed position and an open position as the apparatus is folded or unfolded.

BACKGROUND

The size of an apparatus, such as a tablet or a smartphone, is an important consideration in the apparatus design process. A user oftentimes wants the outer dimensions of the apparatus to be as small as possible while still providing a display that is as large as possible.

This problem may be solved by means of a foldable apparatus comprising one or several support bodies that are interconnected by means of a hinge and support the display. The support body/bodies and the display can be folded together to provide an apparatus which is as small as possible and/or in which the display is protected from external influence such as impact. Correspondingly, when the apparatus is unfolded, a display with a size as large as possible is provided. Foldable apparatuses are, in other words, configured to have a variable width, the width being either minimized or maximized.

One problem associated with such a foldable apparatus is how to provide an apparatus that can be folded to a minimum width without simultaneously increasing the thickness of the apparatus too much. A further problem is related to the hinge construction which oftentimes is very complex and takes up significant much space, along with the folded display, within the apparatus.

SUMMARY

It is an object to provide an improved hinge assembly for a foldable apparatus such as a portable electronic device. The foregoing and other objects are achieved by the features of the independent claim. Further implementation forms are apparent from the dependent claims, the description, and the figures.

According to a first aspect, there is provided a hinge assembly for a foldable apparatus, the hinge assembly being moveable between a closed position and an open position as the apparatus is folded or unfolded. The hinge assembly comprises a first pivotable element configured to pivot around a first pivot axis and a second pivotable element configured to pivot around a second pivot axis. The first pivotable element and the second pivotable element are configured to pivot simultaneously through a first angle and in opposite rotational directions. A first support surface is configured to pivot in relation to the first pivotable element, and a second support surface configured to pivot in relation to the second pivotable element. The first support surface and the second support surface are configured to pivot simultaneously through a second angle and in opposite rotational directions, in response to the pivoting movement of the first pivotable element and the second pivotable element through the first angle.

This allows a space to be formed, between the pivotable elements and the support elements, which accommodates the folding area of the display as it is being folded. When a display folds, the folding area does not fold sharply but forms a teardrop, i.e. the folding area of the display has a larger thickness than, e.g., the edge areas of the display which can extend directly in abutment with each other when the apparatus is folded. The folding area of the display, on the other hand, is folded with a radius, i.e. corresponding sections of display are separated by a gap, the dimensions of which diminishes, and eventually disappears such that the edge areas of the display are in direct contact. The space formed by the present solution allows this teardrop shape of the display to be accommodated within the apparatus without increasing the thickness of the apparatus and without requiring complex arrangements.

In a possible implementation form of the first aspect, the first support surface and the second support surface are configured to extend in a common plane when the hinge assembly is in the open position, the first support surface extending at a third angle to the second support surface when the hinge assembly is in the closed position. This allows the hinge assembly to both support a display in the open position and to accommodate the folded display in the closed position.

In a further possible implementation form of the first aspect, the first pivotable element and the second pivotable element are configured such that a recess is formed between the first pivotable element and the first support surface, and a recess is formed between the second pivotable element and the second support surface as the first pivotable element and the second pivotable element pivot through the first angle towards the closed position, the recess accommodating any deformation of the first support surface and the second support surface as the first support surface and the second support surface simultaneously pivot through the second angle.

In a further possible implementation form of the first aspect, the first angle is between a minimum of 0° and a maximum of 80° to 100°, preferably 90°.

In a further possible implementation form of the first aspect, the second angle is between a minimum of 0° and a maximum of 1° to 45°.

In a further possible implementation form of the first aspect, the first pivotable element comprises an inner end and an outer end, the inner end being arranged adjacent the first pivot axis; the second pivotable element comprising an inner end and an outer end, the inner end being arranged adjacent the second pivot axis; the first support surface comprising an inner end and an outer end; the second support surface comprising an inner end and an outer end; the outer end of the first support surface being configured to pivot in relation to the outer end of the first pivotable element and the outer end of the second support surface being configured to pivot in relation to the outer end of the second pivotable element, the inner end of the first support surface extending adjacent the inner end of the second support surface when the hinge assembly is in the open position, and the outer end of the first support surface extending adjacent the outer end of the second support surface when the hinge assembly is in the closed position.

In a further possible implementation form of the first aspect, hinge assembly is in the open position, the inner end of the first support surface is separated from the inner end of the second support surface by a first gap, and when the hinge assembly is in the closed position, the inner end of the first support surface is separated from the inner end of the second support surface by a second gap, the second gap being larger than the first gap, freeing up space accommodating the folded and deformed display.

In a further possible implementation form of the first aspect, when the hinge assembly is in the open position, the outer end of the first support surface is separated from the outer end of the second support surface by a combined total width of the first support surface, the second support surface, and the first gap. In a further possible implementation form of the first aspect, the second pivot axis extends in parallel with the first pivot axis, and/or the first support surface extends in parallel with the first pivot axis and the second support surface extends in parallel with the second pivot axis.

In a further possible implementation form of the first aspect, the first support surface and the second support surface are configured to support a foldable display of the foldable apparatus, the recess forming a cavity accommodating a folded section of the foldable display. Hence, the hinge assembly is as non-complex as possible, and does not significantly add to the number of components of the apparatus.

In a further possible implementation form of the first aspect, the hinge assembly further comprises a housing configured to guide the first pivotable element and the second pivotable element during the pivoting movement, the inner end of the first pivotable element and the inner end of the second pivotable element being operatively coupled to the housing. The housing both guides and protects the hinge assembly, as well as maintains it as one component group.

In a further possible implementation form of the first aspect, the inner end of the first pivotable element and the inner end of the second pivotable element are configured to overlap, along a center axis of the housing, when the hinge assembly is in the open position, allowing the hinge assembly to take up as little space as possible.

In a further possible implementation form of the first aspect, the outer end of the first support surface and the outer end of the second support surface are configured to be separated by a third gap when the hinge assembly is in the closed position, the second gap being larger than the third gap. This facilitates sections of display to extend in parallel, adjacent each other, when the hinge assembly is in the closed position and, hence, the apparatus is folded.

In a further possible implementation form of the first aspect, the inner end of the first pivotable element and the inner end of the second pivotable element are configured to slide within the housing during the pivoting movement, the sliding movement being restricted to directions perpendicular to the first pivot axis and the second pivot axis. In a further possible implementation form of the first aspect, the sliding movement is restricted by means of a first set of grooves accommodating the inner end of the first pivotable element and a second set of grooves accommodating the inner end of the second pivotable element.

In a further possible implementation form of the first aspect, the first pivotable element and the second pivotable element being pivoted simultaneously at the same angular speed.

In a further possible implementation form of the first aspect, when the hinge assembly is in the open position, the inner end of the first pivotable element comprises a protrusion configured to engage the inner end of the second support surface, and the inner end of the second pivotable element comprises a protrusion configured to engage the inner end of the first support surface, and wherein, when the hinge assembly is in the closed position, the protrusions are configured to disengage the first support surface and the second support surface. This allows the number of components to be reduced while still providing sufficient support for the display when the hinge assembly is in the open position.

In a further possible implementation form of the first aspect, the housing is configured to partially engage the first support surface and the second support surface when the hinge assembly is in the open position, providing a hinge assembly that is even more stable when in the open position.

In a further possible implementation form of the first aspect, the hinge assembly further comprises guide structures configured to move the inner end of the first support surface and the inner end of the second support surface away from each other as the hinge assembly is being moved towards the closed position, ensuring the two halves of the hinge assembly are opened and closed securely and reliably.

In a further possible implementation form of the first aspect, each guide structure comprises a stationary element and a movable element, the stationary element extending from the housing or one of the first support surface and the second support surface, the movable element extending from one of the first support surface and the second support surface or the housing. This reduces the need for separately operated guiding components. In a further possible implementation form of the first aspect, the stationary element comprises a pin and the movable element comprises a groove or surface configured to slide across the pin in response to the pivoting movement, the sliding movement forcing the first support surface or the second support surface to move in a direction towards or away from the other of the first support surface and the second support surface. These elements are easily made part of other hinge assembly components.

In a further possible implementation form of the first aspect, each guide structure comprises a spring element extending between the housing and the first support surface or the second support surface.

According to a second aspect, there is provided a foldable apparatus, the apparatus being moveable between a closed position and an open position and comprising at least one hinge assembly according to the above, a foldable display, and a foldable body comprising a first body section and a second body section, each body section comprising a display backing surface supporting a part of the foldable display, the first body section and the second body section being interconnected by the hinge assembly such that the display backing surfaces of the first body section and the second body section extend in parallel when the apparatus is in the closed position and in a common plane when the apparatus is in the open position.

This allows the apparatus to fold while still preventing the surface layer, such as the display of the electronic device, from becoming wrinkled and/or permanently deformed due to folding. Furthermore, the hinge assembly provides both a stable open position as well as a stable folded and closed position, which prevents accidental folding beyond the mechanical limits of the apparatus.

In a possible implementation form of the second aspect, the outer end of the first pivotable element is fixedly connected to an inner surface area of the first body section and the outer end of the second pivotable element is fixedly connected to an inner surface area of the second body section, each inner surface area extending at a fourth angle > 0° to the display backing surface.

This and other aspects will be apparent from and the embodiments described below. BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed portion of the present disclosure, the aspects, embodiments, and implementations will be explained in more detail with reference to the example embodiments shown in the drawings, in which:

Fig. 1 shows a schematic side view of a hinge assembly in accordance with one embodiment of the present invention, wherein the hinge assembly is in an open position;

Fig. 2 shows a schematic side view of a foldable apparatus in accordance with one embodiment of the present invention, wherein the apparatus is unfolded and the hinge assembly is in the open position;

Fig. 3 shows a schematic side view of the hinge assembly shown in Fig. 1, wherein the hinge assembly is in a closed and folded position;

Fig. 4 shows a partial side view of the foldable apparatus shown in Fig. 2, wherein the apparatus is closed and folded, and the hinge assembly is in the closed position;

Fig. 5 shows a partial cross-sectional view of a hinge assembly in accordance with one embodiment of the present invention, wherein the hinge assembly is in the closed position;

Fig. 6 shows a partial cross-sectional view of a foldable apparatus in accordance with one embodiment of the present invention, wherein the foldable apparatus is closed and folded and the hinge assembly is in the closed position;

Fig. 7 shows a partial cross-sectional view of the hinge assembly shown in Fig. 5, wherein the hinge assembly is in the open position;

Fig. 8 shows a partial cross-sectional view of the foldable apparatus shown in Fig. 6, wherein the foldable apparatus is open and unfolded and the hinge assembly is in the open position.

DETAILED DESCRIPTION

Figs. 1 to 4 show a hinge assembly 1 for a foldable apparatus 2, the hinge assembly 1 being moveable between a closed position Pl and an open position P2 as the apparatus 2 is folded or unfolded. The closed position Pl is shown in Figs. 2 and 4, and the open position P2 is shown in Figs. 1 and 3. The foldable apparatus 2, such as a tablet or a smartphone, or any mobile communication device such as mobile phone, desktop computer, is also moveable between the closed position Pl and the open position P2, in other words, both the hinge assembly 1 and the foldable apparatus 2 are located in the closed position Pl or in the open position P2, or are moved simultaneously between the closed position Pl and the open position P2.

As shown in Fig. 2, the apparatus 2 comprises the hinge assembly 1, described in more detail below, a foldable display 10, and a foldable body comprising a first body section 16a and a second body section 16b. The first body section 16a and the second body section 16b may be two individual sections as shown in Fig. 2, or two parts of a single-piece body (not shown). The first body section 16a and the second body section 16b may be interconnected by means of the hinge assembly 1 or by other, additional folding elements.

Each body section 16a, 16b comprises a display backing surface 17a, 17b which supports a part of the foldable display 10 respectively, e.g., the parts of the display 10 which do not extend immediately adjacent hinge assembly 1.

The first body section 16a and the second body section 16b are interconnected by the hinge assembly 1 such that the display backing surfaces 17a, 17b of first body section 16a and the second body section 16b extend in parallel when the apparatus 2 is in the closed position Pl (not shown) and in a common plane when the apparatus 2 is in the open position P2, as shown in Fig. 2.

The hinge assembly 1, shown in most detail in Figs. 1 and 3, comprises a first pivotable element 3 configured to pivot around a first pivot axis Al and a second pivotable element 4 configured to pivot around a second pivot axis A2. As shown in Fig. 3, the second pivot axis A2 may extend in parallel with the first pivot axis Al.

The first pivotable element 3 and the second pivotable element 4 are configured to pivot simultaneously through a first angle a and in opposite rotational directions, optionally at the same angular speed. This allows the main part of the first pivotable element 3 and the main part of the second pivotable element 4 to be pivoted substantially towards each other when the apparatus 2 is folded and closed, and substantially away from each other when the apparatus 2 is unfolded and opened. The first angle a may be between 0° and 80-100°, preferably 90°. For example when the hinge assembly 1 is in the open position P2, the first angle a may have a minimum of 0° and, when the hinge assembly 1 is in the closed position Pl, the first angle a may have a maximum of 80-100°, preferably 90°.

The hinge assembly further comprises a first support surface 5 configured to pivot in relation to the first pivotable element 3, and a second support surface 6 configured to pivot in relation to the second pivotable element 4. The first support surface 5 extends in parallel with the first pivot axis Al and the second support surface 6 extends in parallel with the second pivot axis A2.

The first support surface 5 and the second support surface 6 are configured to pivot simultaneously through a second angle P and in opposite rotational directions, in response to the above-mentioned pivoting movement of the first pivotable element 3 and the second pivotable element 4 through the first angle a. The second angle P may be between a minimum of 0°, e.g. when the hinge assembly 1 is in the open position P2, and a maximum of 1° to 45°, e.g. when the hinge assembly 1 is in the closed position Pl. The first angle a and the second angle P may both be at a minimum, e.g. at 0°, when the apparatus is open and the hinge assembly 1 in the open position P2. Correspondingly, the first angle a and the second angle P may both be at a maximum, e.g. at 90° and 45° respectively, when the apparatus is folded and the hinge assembly 1 in the closed position Pl.

The first support surface 5 may extend at a third angle y to the second support surface 6 when the hinge assembly 1 is in the closed position Pl, as shown in Fig. 3. The first support surface 5 and the second support surface 6 may be configured to extend in a common plane when the hinge assembly 1 is in the open position P2, as shown in Figs. 1 and 2, i.e. the third angle y being 180°.

The first pivotable element 3 and the second pivotable element 4 may be configured such that a recess 19a is formed between the first pivotable element 3 and the first support surface 5, and a corresponding recess 19b is formed between the second pivotable element 4 and the second support surface 6, as the first pivotable element 3 and the second pivotable element 4 pivot through the first angle a towards the closed position Pl. The recesses 19a, 19b are indicated in Fig. 1. The recesses 19a, 19b accommodate any deformation or movement of the first support surface 5 and the second support surface 6 as the first support surface 5 and the second support surface 6 simultaneously pivot through the second angle p.

The first pivotable element 3 may comprise an inner end 3a and an outer end 3b, the inner end 3a being arranged adjacent the first pivot axis Al. The inner end 3a may be a peripheral edge or a peripheral area of the first pivotable element 3, and the inner end 3 a may extend in parallel with the first pivot axis Al. The outer end 3b may be a peripheral edge or a peripheral area of the first pivotable element 3, and the outer end 3b may extend in parallel with the first pivot axis Al. The first pivot axis Al may be coplanar with the inner end 3a and/or outer end 3b when the hinge assembly 1 is in the open position P2.

Correspondingly, the second pivotable element 4 may comprise an inner end 4a and an outer end 4b, the inner end 4a being arranged adjacent the second pivot axis A2. The inner end 4a may be a peripheral edge or a peripheral area of the second pivotable element 4, and the inner end 4a may extend in parallel with the second pivot axis A2. The outer end 4b may be a peripheral edge or a peripheral area of the second pivotable element 4, and the outer end 4b may extend in parallel with the second pivot axis A2. The second pivot axis A2 may be coplanar with the inner end 4a and/or outer end 4b when the hinge assembly 1 is in the open position P2.

As mentioned above, the apparatus 2 may comprise a foldable body comprising a first body section 16a and a second body section 16b. The first body section 16a may comprise an inner surface area 18a and, correspondingly, the second body section 16b may comprise an inner surface area 18b. Each inner surface area 18a, 18b extends at a fourth angle 6 > 0° to the display backing surface 17a, 17b, i.e., at an angle 6 to the common plane. This allows a space to be formed between the body sections 16a, 16b and the display 10, this space allowing any bulging section or other deformed display area to be accommodated within the apparatus 2 when the apparatus 2 has been folded, as shown in Fig. 4. Furthermore, the outer end 3b of the first pivotable element 3 may be fixedly connected to the inner surface area 18a of the first body section 16a and the outer end 4b of the second pivotable element 4 may correspondingly be fixedly connected to the inner surface area 18b of the second body section 16b. The inner end 3 a of the first pivotable element 3 may extend adjacent, optionally overlap with, the inner end 4a of the second pivotable element 4 when the hinge assembly 1 is in the open position P2 and/or in the closed position Pl. The outer end 3b of the first pivotable element 3 may be at a maximum distance from the outer end 4b of the second pivotable element 4 when the hinge assembly 1 is in the open position P2.

The first support surface 5 may comprise an inner end 5a and an outer end 5b, the inner end 5a and the outer end 5b may be oppositely extending peripheral edges or peripheral areas of the first support surface 5. The second support surface 6 may comprise an inner end 6a and an outer end 6b, the inner end 6a and the outer end 6b may be oppositely extending peripheral edges or peripheral areas of the second support surface 6.

The outer end 5b of the first support surface 5 may be configured to pivot in relation to the outer end 3b of the first pivotable element 3 and the outer end 6b of the second support surface 6 may be configured to pivot in relation to the outer end 4b of the second pivotable element 4, as shown in Figs. 1 and 3 and Figs. 2 and 4, respectively.

The inner end 5 a of the first support surface 5 extends adjacent the inner end 6a of the second support surface 6 when the hinge assembly 1 is in the open position P2, as shown in Figs. 1 and 2. The outer end 5b of the first support surface 5 extends adjacent the outer end 6b of the second support surface 6 when the hinge assembly 1 is in the closed position Pl, as shown in Figs. 3 and 4.

When the hinge assembly 1 is in the open position P2, the inner end 5a of the first support surface 5 may be separated from the inner end 6a of the second support surface 6 by a first gap 7, as shown in Figs. 1 and 2. When the hinge assembly 1 is in the closed position Pl, the inner end 5 a of the first support surface 5 may be separated from the inner end 6a of the second support surface 6 by a second gap 8, the second gap 8 being larger than the first gap 7.

The outer end 5b of the first support surface 5 and the outer end 6b of the second support surface 6 may be configured to be separated by a third gap 9 when the hinge assembly 1 is in the closed position Pl, the second gap 8 being larger than the third gap 9 as shown in Fig. 3. Furthermore, when the hinge assembly 1 is in the open position P2, the outer end 5b of the first support surface 5 is separated from the outer end 6b of the second support surface 6 by a combined total width of the first support surface 5, the second support surface 6, and the first gap 7, preferably as seen in the common plane and as shown in Figs. 1 and 2.

The first support surface 5 and the second support surface 6 may be configured to support the foldable display 10 of the foldable apparatus 2, the recesses 19a, 19b forming a cavity accommodating a folded section of the foldable display 10, the folded section optionally having a teardrop shape.

The hinge assembly 1 may further comprise a housing 11 configured to guide the first pivotable element 3 and the second pivotable element 4 during their pivoting movement. The inner end 3 a of the first pivotable element 3 and the inner end 4a of the second pivotable element 4 may be operatively coupled to the housing 11. The housing 11 and the inner ends 3a, 4a may comprise corresponding, semicircular sections allowing the first pivotable element 3 and the second pivotable element 4 to pivot within the housing 11.

The inner end 3a of the first pivotable element 3 and the inner end 4a of the second pivotable element 4 may be configured to slide within the housing 11 during the pivoting movement, the sliding movement being restricted to directions perpendicular to the first pivot axis Al and the second pivot axis A2. The sliding movement may be restricted by means of a first set of grooves 13a accommodating the inner end 3 a of the first pivotable element 3 and a second set of grooves 13b accommodating the inner end 4a of the second pivotable element 4. The first set of grooves and second set of grooves 13b may limit the movement of the first pivotable element 3 and the second pivotable element 4 to pivoting movement around the first pivot axis Al and the second pivot axis A2, in a plane extending perpendicular to the first pivot axis Al and the second pivot axis A2.

The inner end 3a of the first pivotable element 3 and the inner end 4a of the second pivotable element 4 may be configured to overlap along a center axis A3 of the housing 11, when the hinge assembly 1 is in the open position P2, as shown in Figs. 1 and 2. The inner end 3 a of the first pivotable element 3 and the inner end 4a of the second pivotable element 4 may also be configured to overlap, but to a lesser degree, when the hinge assembly 1 is in the closed position Pl (not shown). The inner end 3a of the first pivotable element 3 may comprise a protrusion 14a configured to, when the hinge assembly 1 is in the open position P2, engage the inner end 6a of the second support surface 6. Correspondingly, the inner end 4a of the second pivotable element 4 may comprises a protrusion 14b configured to engage the inner end 5a of the first support surface 5. When the hinge assembly 1 is in the closed position Pl, the protrusions 14a, 14b are configured to disengage the first support surface 5 and the second support surface 6.

The housing 11 may be configured to partially engage the first support surface 5 and the second support surface 6 when the hinge assembly 1 is in the open position P2, as shown in Figs. 1 and 2.

The hinge assembly may further comprise guide structures 15 configured to move the inner end 5 a of the first support surface 5 and the inner end 6a of the second support surface 6 away from each other as the hinge assembly 1 is being moved towards the closed position Pl. The guide structures are shown in more detail in Figs. 5 to 8.

Each guide structure 15 may comprise a stationary element 15a and a movable element 15b, the stationary element 15a extending from the housing 11 as shown in Figs. 5 to 8, the first support surface 5 or the second support surface 6. The movable element 15b correspondingly extends from the first support surface 5, the second support surface 6 as shown in Figs. 5 to 8, or the housing 11 such that the stationary element 15a and the movable element 15b are connected to different components and allow said components to be guided relative each other. In one embodiment, one stationary element 15a extends from the first support surface 5 and a further stationary element 15a extends from the second support surface 6, each stationary element 15a interacting with a movable element 15b which extends from the housing 11.

As shown in Figs. 5 to 8, the stationary element 15a may comprise a pin and the movable element 15b may comprise a groove or surface configured to slide across the pin 15a in response to pivoting movement. The sliding movement forces the first support surface 5, or the second support surface 6, to move in a direction towards or away from the other of the first support surface 5 and the second support surface 6. The movable element 15b may be any kind of element comprising a curved surface configured to allow the first support surface 5 and the second support surface 6 to pivot within the housing 11, while at the same time limiting movement to follow a desired path to, e.g., avoid the display 10 being folded incorrectly or pinched between elements. The movable element 15b may form a closed loop together with the support surface 5,6 such that the stationary element 15a is substantially enclosed by the movable element 15b, the movable element 15b pivoting such that the stationary element 15a is located at one end of the loop when the hinge assembly 1 is in the open position P2, and at an opposite end of the loop when the hinge assembly 1 is in the closed position Pl.

Each guide structure 15 may also, or alternatively, comprise a spring element extending between the housing 11 and the first pivotable element 3 or the second pivotable element 4, between the first body section 16a and the first support surface 5, or between the second body section 16b and the second support surface 6 (not shown).

Furthermore, the first pivotable element 3 may be part of the first body section 16a, and the second pivotable element 4 part of the second body section 16b such that thy are not fixedly connected, but rather extend from one another.

The various aspects and implementations have been described in conjunction with various embodiments herein. However, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed subject-matter, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage.

The reference signs used in the claims shall not be construed as limiting the scope. Unless otherwise indicated, the drawings are intended to be read (e.g., cross-hatching, arrangement of parts, proportion, degree, etc.) together with the specification, and are to be considered a portion of the entire written description of this disclosure. As used in the description, the terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate.