Note: Descriptions are shown in the official language in which they were submitted.
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SINGLE-BLADE RAZOR APPARATUS
[00011 <Blank>
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BACKGROUND
Technical Field
[0002] Embodiments described herein relate to the field of shaving tools,
and more
particularly, to a single-blade razor and methods of manufacturing the same.
Descrintion of the Related Art
[0003] Since the latter part of the 20th century, the market for shaving
tools has been
dominated by the trend of including an ever-larger number of low-quality
blades in a disposable
cartridge. For example, whereas a two-blade cartridge was once considered
revolutionary,
currently five- and six-blade cartridges command increasing market share.
[0004] Evidence that such multi-blade cartridges actually improve shaving
performance is
scant, however. In fact, the present inventors have recognized a well-designed
razor using a
single, high quality blade can provide a shaving experience that is superior
to that of multi-blade
cartridges. These inventors' continuing research into the design of single-
blade shaving systems
has yielded additional discoveries that may further improve the quality of the
single-blade
shaving experience and the durability of the single-blade razor itself.
SUMMARY
[0005] Various embodiments of a razor apparatus and methods for manufacturing
the same
are disclosed. In an embodiment, a razor apparatus may include a handle and a
head pivotably
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mounted on the handle. The head may include a rear side including an aperture
for receiving a
single blade, as well as a front side through which a cutting edge of the
single blade is exposed
during use. The head may further include an upper portion and a lower portion
that form the
aperture. The lower portion may physically interface with the upper portion so
that a front
region of the upper portion is physically supported by the lower portion.
[0006] In a particular implementation of the razor apparatus, to
physically interface with the
upper portion, the lower portion may include several protruding latches
located in the area
proximate the front side of the head. The protruding latches may respectively
mate with a
number of recesses formed in the upper portion. Alternatively, the latches may
be formed in the
upper portion and may respectively mate with recesses formed in the lower
portion.
[0007] An embodiment of a method of manufacturing a razor apparatus may
include
fabricating a lower portion and an upper portion of a head of the razor
apparatus, where the lower
portion and the upper portion are fabricated to physically interface with each
other, when
assembled, at a front region and a rear region of the head. The method may
further include
assembling the lower portion and the upper portion of the head. When
assembled, the lower and
upper portions of the head may engage so that at the front region of the head,
the upper portion is
physically supported by the lower portion. Upon assembly, the lower and upper
portions of the
head may form an aperture for receiving a single blade. In a particular
implementation, the
fabricating may be performed using a metal injection molding process.
[0008] In another embodiment, a razor apparatus may include a handle and a
head pivotably
mounted on the handle, where the head may include an aperture for receiving a
single blade. The
head may further include a means for retaining the single blade, where the
means for retaining
the single blade is configured to retain the single blade during use while
permitting the single
blade to move in two or more dimensions within the means for retaining the
single blade during
use.
[0009] In a particular implementation, the means for retaining the single
blade may include a
number of retaining posts, each configured to mate with a respective recess in
the single blade to
retain the single blade within the head. In a further implementation, the
retaining posts may be
spaced to retain the single blade during use while permitting the single blade
to move in at least
two dimensions during use.
[0010] In another embodiment, a method of manufacturing a razor apparatus
may include
fabricating a lower portion and an upper portion of a head, where the lower
portion includes a
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number of retaining posts. The method may further include assembling the lower
portion and the
upper portion of the head. When assembled, the lower and upper portions of the
head may form
an aperture for receiving a single blade. Each of the retaining posts may be
configured to mate
with a respective recess in the single blade to retain the single blade within
the head upon
insertion of the single blade. Further, the retaining posts may be spaced to
retain the single blade
during use while permitting the single blade to move in at least two
dimensions during use. In a
particular implementation, the fabricating may be performed using a metal
injection molding
process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The above and further advantages of the methods and mechanisms may be
better
understood by referring to the following description in conjunction with the
accompanying
drawings, in which:
[0012] FIG. 1 illustrates an embodiment of a razor apparatus.
[0013] FIG. 2 illustrates a top view of a head of the razor apparatus of
FIG. 1.
[0014] FIG. 3 illustrates a profile view of an embodiment of a razor head.
[0015] FIG. 4 is a cutaway view of the razor head profile view of FIG. 3
that shows certain
internal structures of the head.
[0016] FIG. 5 presents a view of embodiments of a lower and upper portion
of a razor head,
oriented to show their internal surfaces.
[0017] FIG. 6 illustrates a view of a razor head in which the lower and
upper portions have
been assembled together, as viewed from a rear side of the head.
[0018] FIG. 7 shows an exploded view of an embodiment of a razor head in
profile, further
illustrating aspects of the lower and upper portions.
[0019] FIG. 8 is a schematic diagram illustrating an interaction between a
razor apparatus and
a skin surface, and illustrating several parameters that may characterize such
interaction.
[0020] FIG. 9 illustrates an embodiment of a lower portion of a razor head
that may be
configured to permit blade movement in multiple dimensions during use.
[0021] FIG. 10 corresponds to the view of the lower portion of FIG. 9 with
a single blade
inserted.
[0022] FIG. 11 illustrates an embodiment of an upper portion of a razor
head that may be
configured to support a single blade from above.
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100231 FIGs. 12-13 present additional views of the upper and lower
portions shown in FIGs.
9-11.
100241 FIG. 14 is a flow chart illustrating an embodiment of a method of
manufacturing a
razor apparatus.
100251 FIG. 15 is a flow chart illustrating a different embodiment of a
method of
manufacturing a razor apparatus.
DETAILED DESCRIPTION OF EMBODIMENTS
Introduction and terminology
100261 In the following description, numerous specific details are set
forth to provide a
thorough understanding of the methods and mechanisms presented herein.
However, one having
ordinary skill in the art should recognize that the various embodiments may be
practiced without
these specific details. In some instances, well-known structures, components,
signals, computer
.. program instructions, and techniques have not been shown in detail to avoid
obscuring the
approaches described here. It will be appreciated that for simplicity and
clarity of illustration,
elements shown in the figures have not necessarily been drawn to scale. For
example, the
dimensions of some of the elements may be exaggerated relative to other
elements.
100271 This specification includes references to "an embodiment." The
appearance of the
phrase -in an embodiment" in different contexts does not necessarily refer to
the same
embodiment. Particular features, structures, or characteristics may be
combined in any suitable
manner consistent with this disclosure. Furthermore, as used throughout this
application, the
word "may- is used in a permissive sense (i.e., meaning "having the potential
to-), rather than
the mandatory sense (i.e., meaning "must"). Similarly, the words "include,"
"including," and
"includes" mean including, but not limited to.
100281 Terminology. The following paragraphs provide definitions and/or
context for terms
found in this disclosure (including the appended claims):
100291 -Comprising." This term is open-ended. As used in the appended
claims, this term
does not foreclose additional structure or steps. Consider a claim that
recites: "A system
.. comprising a processor ...." Such a claim does not foreclose the system
from including
additional components (e.g., a display, a memory controller).
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100301 "Configured To." Within this disclosure, different entities (which
may variously be
referred to as "units," "circuits," other components, etc.) may be described
or claimed as
"configured" to perform one or more tasks or operations. This
formulation¨[entity] configured
to [perform one or more tasksj¨is used herein to refer to structure (i.e.,
something physical, such
as an electronic circuit or mechanical apparatus). More specifically, this
formulation is used to
indicate that this structure is arranged to perform the one or more tasks
during operation. A
structure can be said to be "configured to" perform some task even if the
structure is not
currently being operated. A "temperature circuit configured to measure an
internal operating
temperature of a processing element" is intended to cover, for example, an
integrated circuit that
has circuitry that performs this function during operation, even if the
integrated circuit in
question is not currently being used (e.g., a power supply is not connected to
it). Thus, an entity
described or recited as -configured to" perform some task refers to something
physical, such as a
device, circuit, memory storing program instructions executable to implement
the task, etc. This
phrase is not used herein to refer to something intangible. Thus the
"configured to" construct is
not used herein to refer to a software construct such as an application
programming interface
(API).
100311 "Based On." As used herein, this term is used to describe one or
more factors that
affect a determination. This term does not foreclose additional factors that
may affect a
determination. That is, a determination may be solely based on those factors
or based, at least in
part, on those factors. Consider the phrase "determine A based on B." While B
may be a factor
that affects the determination of A, such a phrase does not foreclose the
determination of A from
also being based on C. In other instances, A may be determined based solely on
B. "Dependent
on" may be employed as a synonym for "based on."
100321 "In Response To." As used herein, this term is used to describe
causality of events or
conditions. For example, in the phrase "B occurs in response to A," there is a
cause-and-effect
relationship in which A causes B to occur. It is noted that this phrase does
not entail that A is the
only event that causes B to occur; B may also occur in response to other
events or conditions that
may be independent of or dependent on A. Moreover, this phrase does not
foreclose the
possibility that other events or conditions may also be required to cause B to
occur. For
example, in some instances, A alone may be sufficient to cause B to happen,
whereas in other
instances, A may be a necessary condition, but not a sufficient one (such as
in the case that "B
occurs in response to A and C").
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100331 "Each." With respect to a plurality or set of elements, the term
"each" may be used to
ascribe some characteristic to all the members of that plurality or set. But
absent language to the
contrary, use of "each" does not foreclose the possibility that other
instances of the element
might not include the characteristic. For example, in the phrase "a plurality
of widgets, each of
which exhibits property A," there must be at least two (and possibly
arbitrarily many) widgets
that exhibit property A. But without more, this does not foreclose the
possibility of an additional
widget, not a member of the plurality, that does not exhibit property A. In
other words, absent
language to the contrary, the term "each" does not refer to every possible
instance of an element,
but rather every element in a particular plurality or set.
Overview of razor apparatus and head support structures
100341 Turning now to FIG. 1, an embodiment of a razor apparatus is
shown. (Preliminarily,
it is noted that while the drawings attempt to faithfully reproduce details of
actual embodiments,
none of the drawings provided here should be interpreted as precise scale
drawings.) Razor
apparatus 100 includes a handle 102 and a head 104 pivotably attached to
handle 102. FIG. 2
illustrates a top view of head 104. In the illustrated embodiment, head 104
includes a rear side
110 that includes an aperture (not labeled in FIG. 2) for receiving a single
blade 200. When
inserted into head 104, a cutting edge 210 of blade 200 may be exposed through
a front side 115
of head 104, and a rear edge 220 of blade 200 may face the rear side 110.
Blade 200 includes
blade face 250, which may include cutouts or recesses that are not employed by
head 104 (e.g.,
recesses for mounting blade 200 in other types of razors). In some
embodiments, blade 200 may
be inserted so that blade face 250 faces either up or down, while in other
embodiments, blade 200
may specify a particular orientation for blade face 250.
100351 In an embodiment, blade 200 may have a length (denoted dl) of
about 38.4 mm, and a
width (denoted d2) of about 18.4 mm. All measurements stated herein are
subject to ordinary
manufacturing tolerances for the process used to manufacture the item in
question. For example,
a sampling of a particular model of blades 200 yielded dl in the range of
38.396 mm ¨ 38.437
mm, and d2 in the range of 18.360 mm ¨ 18.397 mm. Additionally, blade 200 may
include a
number of recesses 215 which, as will be described below, may mate with
retaining posts of head
104 in order to retain blade 200 within head 104 during use. In the
illustrated embodiment,
recesses 215 are approximately semicircular in shape, and may measure about
4.0 mm (e.g.,
3.985 mm ¨ 3.998 mm) along dimension d3 and about 1.84 mm (e.g., 1.831 mm ¨
1.842 mm)
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along dimension d4. Recesses 215 may be located about 1.85 mm from the rear
edge of blade
200 along dimension d5 (e.g., 1.827 mm¨ 1.873 mm).
100361 It is noted that in other embodiments of blade 200 and razor
apparatus 100, these
dimensions may vary. In particular, recesses 215 may assume shapes other than
semicircular.
Additionally, different embodiments of blade 200 may employ similar shapes and
dimensions for
recesses 215, but may vary the location of recesses 215 within blade 200
(e.g., by varying
dimension d5). The relative positioning of recesses 215 may affect the
relative degree of
exposure of cutting edge 210 upon insertion of blade 200, which may in turn
alter the shaving
characteristics of razor apparatus 100.
100371 FIG. 3 illustrates a profile view of head 104. As shown, head 104
includes a lower
portion 120 and an upper portion 130, as well as a pivot mount 140 through
which head 104 may
pivotably attach to handle 102. Upper portion 130 further includes a pair of
side walls 135 (only
one of which is shown in the view of FIG. 3) that form exterior side faces of
head 104. In this
view, rear side 110 of head 104 faces to the left, and front side 115 faces to
the right.
100381 In one design approach, the front region of upper portion 130 (i.e.,
the part of upper
portion 130 that faces front side 115 of head 104) may effectively "float"
over lower portion 120.
That is, although the rear region of upper portion 130 may be attached to
lower portion 120, the
front region may extend over lower portion 120 without making physical contact
with lower
portion 120. In this approach, upper portion 130 may retain blade 200 from
above, but there may
be a gap between upper portion 130 and lower portion 120. Depending on the
materials used to
construct head 104, such a gap may affect the structural integrity of head
104. For example.
without physical support, the front region of upper portion 130 may bend or
break on impact,
such as if razor apparatus 100 is dropped.
100391 By contrast, in the embodiment of FIG. 3, lower portion 120 is
designed to physically
interface with upper portion 130 so that when head 104 is assembled, the front
region of upper
portion 130 is physically supported by lower portion 120. By permitting lower
portion 120 and
upper portion 130 to be secured to one another at multiple distinct points at
both the front and
rear regions of upper portion 130, the overall structural integrity of head
104 may be improved
(e.g., with respect to impact).
100401 FIG. 4 illustrates an embodiment of a particular mechanism through
which the front
region of upper portion 130 may be physically supported by lower portion 120.
The view of
FIG. 4 is a cutaway view of FIG. 3 that shows an example of the internal
structure of head 104
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behind side wall 135. Specifically, FIG. 4 shows that the visible end of upper
portion 130
physically rests on lower portion 120. Moreover, lower portion 120 includes a
protruding feature
145, also referred to herein as a "latch," that mates with a corresponding
recess within upper
portion 130.
100411 Further details regarding latch 145 and other elements of head 104
are shown in FIG.
5. In the view presented by FIG. 5, lower portion 120 and upper portion 130
are separated and
partially pivoted away from the viewer in order to illustrate their interior
surfaces as viewed from
rear side 110 of head 104. In the illustrated embodiment, lower portion 120 is
shown to include
latches 145 within side walls 150 at both ends, where the latches are
proximate front side 115 of
head 104 (e.g., closer to front side 115 than to rear side 110). Moreover,
upper portion 130 is
shown to include recesses 155 within both of its side walls 135. As
illustrated by the dotted
lines, latches 145 are configured to mate with recesses 155 (e.g., in a tongue-
and-groove fashion)
when lower portion 120 and upper portion 130 are assembled. Retaining posts
180, which may
be configured to engage with recesses 215 of blade 200, are also shown, and
will be discussed in
greater detail with respect to later drawings.
100421 As shown in FIG. 5, the rear regions of lower portion 120 and upper
portion 130 also
include mounting points 160. Mounting points 160 may be, for example, holes
through which a
screw, pin, or other type of fastener may be inserted in order to fixedly
secure lower portion 120
and upper portion 130 together. In some embodiments, mounting points 160 may
correspond to
spot welds or points of adhesion using a chemical adhesive. Moreover, in some
embodiments,
lower portion 120 may be secured to upper portion 130 along a continuous
region (e.g., along a
welded or adhered length) rather than at discrete points.
100431 When the rear regions of lower portion 120 and upper portion 130
are secured at
mounting points 160, the engagement of latches 145 with their corresponding
recesses 155 may
enable the front region of upper portion 130 to be securely attached to and
physically supported
by lower portion 120 through frictional engagement alone (e.g., without need
for adhesives),
although the attachment may be further enhanced with adhesives or welding if
desired.
100441 Latches 145 may be considered a means for physically supporting
upper portion 130.
However, it is noted that latches 145 need not be formed in lower portion 120.
In an alternative
.. embodiment, the orientation of latches 145 and recesses 155 may be
reversed, such that latches
145 are formed within upper portion 130 and recesses 155 are formed within
lower portion 120.
This may (but need not) include relocating side walls 135 to lower portion
120. It is also noted
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that many equivalents to latches 145 exist. For example, recesses 155 may
correspond to
grooves within side walls 135 rather than notches, and latches 145 may
correspondingly be
relocated within side walls 150 to mate with such grooves. Generally speaking,
latches 145 may
encompass any type of protrusion in one portion of head 104 that is
specifically formed to mate
with a corresponding recess in the other portion of head 104 in order to
physically support a front
region of upper portion 130.
100451 FIG. 6 illustrates a view of head 104 in which lower portion 120
and upper portion 130
have been assembled together, as viewed from rear side 110 of head 104. It can
be seen that
lower portion 120 and upper portion 130 form an aperture 185 into which blade
200 may be
inserted, as mentioned above with respect to FIG. 2. FIG. 6 further
illustrates that retaining posts
180 protrude at least partially through upper portion 130 into aperture 185.
In some
embodiments, the exposure of retaining posts 180 above the surface of upper
portion 130 may be
0.8 mm with a manufacturing tolerance of +/- 0.05 mm.
100461 FIG. 7 illustrates an exploded view of head 104 in profile, in
order to further illustrate
the elements of head 104 and their interrelationship. For clarity of
presentation, not every
element appearing in FIG. 5 is labeled in FIG. 7. FIG. 7 does call out lower
support elements
190 and upper support elements 195, which will be discussed in greater detail
below.
Blade movement properties and shaving characteristics
100471 The shaving performance of a single blade razor such as razor
apparatus 100 may be
characterized as a function of several mechanical parameters. One such
characterization is
schematically illustrated in FIG. 8. Specifically, head 104 is shown
interacting with a skin
surface 800. Blade angle 802 is defined as the angle between skin surface 800
and a plane 804 in
which blade 200 resides. Blade gap 806 is defined as the gap between cutting
edge 210 of blade
200 and lower portion 120 of head 104. Blade exposure 808 (shown in the inset
of FIG. 8) is
defined as the depth to which blade 200 protrudes away from lower portion 120
and into skin
surface 800.
100481 Empirical measurements conducted using embodiments of razor
apparatus 100 suggest
that some combinations of the foregoing parameters may yield superior shaving
performance
(e.g., in terms of shave closeness, effort, comfort, and/or other
characteristics) relative to others.
One such combination includes a blade angle 802 of 31.3 degrees, a blade gap
806 of 0.65 mm,
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and a blade exposure 808 of 0.15 mm, although other combinations are possible
and
contemplated
100491 It is noted, however, that skin surface 800 is rarely uniform. Its
topography may vary
according to factors such as anatomical features and local skin imperfections
(e.g., moles,
blemishes, scars, warts, and the like). Accordingly, a configuration in which
the parameters
described above are statically maintained¨e.g., by rigidly maintaining the
position of blade 200
within head 104¨may not perform as well as a configuration in which blade 200
is permitted at
least a small degree of movement in various dimensions within head 104 during
use.
100501 FIG. 9 illustrates an embodiment of lower portion 120 that may be
configured to
permit such movement of blade 200. In particular, FIG. 9 illustrates a top
view of the interior
face of lower portion 120. Two retaining posts 180 are shown, as are side
walls 150 and lower
support elements 190. (Although latches 145 are visible in FIG. 9, they are
not necessary to this
embodiment and may be omitted.)
100511 The properties of the illustrated embodiment of lower portion 120
that give rise to
blade movement may be primarily determined by the spacing and dimensions of
retaining posts
180. In the illustrated embodiment, lower portion 120 itself may have a width
(denoted d6) of
20.5 mm with a manufacturing tolerance of +/- 0.15 mm (represented as 20.5 +/-
0.15 mm), and a
length (denoted d7) of 44.7 +/- 0.15 mm. Retaining posts 180 may have a
dimension d8 of 2.0
+/- 0.05 mm and a dimension d9 of 3.95 +/- 0.05 mm. The spacing between
retaining posts 180
(denoted d10) may be 35.0 +/- 0.15 mm.
100521 It is noted that the foregoing dimensions and tolerances are merely
examples and that
other configurations are possible and contemplated. For example, various ones
of the foregoing
dimensions may be altered in order to adjust the blade movement
characteristics discussed
below. Further, the specified manufacturing tolerances may differ for
different manufacturing
processes. Additionally, it is noted that the number and shape of retaining
posts 180 may vary in
different embodiments. It is not strictly necessary that the general shape of
retaining posts 180
match that of recesses 215. That is, it may be possible to achieve the results
described here with
a shape of retaining posts 180 that provides fewer points of contact between
retaining posts 180
and recesses 215 than the semicircular shape shown.
100531 FIG. 10 corresponds to the view of lower portion 120 shown in FIG. 9
with blade 200
inserted. As shown in FIG. 10, recesses 215 of blade 200 mate respectively
with retaining posts
180, which will retain blade 200 within head 104 during use. Additionally,
blade 200 is
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supported from below by lower support elements 190 and side walls 150. With
reference to FIG.
11, which illustrates a top view of the interior face of upper portion 130,
blade 200 is also
supported from above by upper support elements 195. (The number and
arrangement of blade
support points within lower portion 120 and upper portion 130 may vary in
various
embodiments.) Generally speaking. the dimensions of lower support elements 190
and upper
support elements 195 will vary depending on the vertical depths of lower
portion 120 and upper
portion 130. These support elements should generally be sized so that they
contact blade 200
and permit blade 200 to pivot around the contact point, without fitting so
tightly that blade 200
cannot otherwise move within head 104. For completeness, additional views of
upper portion
130 and lower portion 120 are shown in FIGs. 12-13, which illustrate these
components from
different angles.
100541 As can be seen by comparing the dimensions and spacing of retaining
posts 180 with
the corresponding dimensions of blade 200 discussed above, retaining posts 180
are slightly
smaller in diameter than recesses 215 of blade 200 (e.g., d9 of about 3.95 mm
for retaining posts
180 versus d3 of about 4.0 mm for recesses 215). Additionally, the effective
spacing between
recesses 215 is about 34.7 mm (e.g., dl of about 38.4 mm ¨ 2*d3 of about 1.84
mm), whereas the
spacing of retaining posts 180 is slightly wider (e.g., dl 0 of about 35.0
mm).
100551 Accordingly, the relative dimensions and spacing of retaining posts
180 in conjunction
with recesses 215 of blade 200 may permit movement of blade 200 in multiple
(e.g., at least two)
dimensions during use. These additional degrees of movement may enable the
position of blade
200 to more readily adapt to non-uniformities in skin surface 800 than a
rigidly retained blade,
which may in turn improve shaving performance. Through empirical testing of
some
embodiments of razor apparatus 100, improved performance may result when blade
200 is
permitted to move along a dimension parallel to cutting edge 210 of blade 200
(e.g., dimension
dl of FIG. 2) in the range of 0.175 ¨ 0.30 mm, with a possible optimum value
within this range
of 0.225 mm. Similarly, improved performance may result when blade 200 is
permitted to move
along a dimension perpendicular to cutting edge 210 of blade 200 (e.g.,
dimension d2 of FIG. 2)
in the range of 0.20 ¨ 0.45 mm, with a possible optimum value within this
range of 0.30 mm.
100561 As noted above, blade 200 may tend to pivot around the support
points presented by
lower support elements 190 and upper support elements 195. That is, in
addition to movement
within the plane of blade 200, blade 200 may also move in a direction
perpendicular to this plane
(e.g., perpendicular to face 250). For example, cutting edge 210 may be
permitted to move along
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a dimension perpendicular to face 250 by 0.15 - 0.375 mm, with a possible
optimum value
within this range of 0.25 mm. Likewise, rear edge 220 may be permitted to move
along a
dimension perpendicular to face 250 by 0.45 - 1.0 mm, with a possible optimum
value within
this range of 0.85 mm.
100571 It is noted that the foregoing ranges are merely examples, and that
other suitable
ranges may be determined for different configurations of blade 200 and head
104.
Materials and fabrication
100581 Generally speaking, the components of razor apparatus 100 may be
manufactured
according to any suitable method from any suitable material. In some
embodiments, various
elements of razor apparatus 100 (e.g., lower portion 120 and upper portion
130, but possibly
including all elements) may be fabricated using a metal injection molding
(MIM) process. In
MIM, a powdered metal feedstock containing a binder may be injected into a
mold in a manner
similar to plastic injection molding (and possibly using the same equipment).
Once the binder
solidifies, the resulting "green- part may be further processed in one or more
steps to remove the
binder and densify the metal particles, often involving sintering the part in
a high-heat
environment (possibly high enough to partially melt the metal).
100591 The finished MIM product may undergo other types of metal
processing, such as
plating, hardening, annealing, etc., similar to metalwork produced via
machining, casting,
forging or other conventional processes, and the resulting part may possess
similar physical
characteristics to parts produced using such conventional processes. Some
machining steps may
be necessary or desired before final assembly. (A typical manufacturing
tolerance for a MIM
may be +/- 0.5% of the length in any direction, although tighter tolerances
may be achieved
through process refinements or post-MIM processing steps such as machining.)
However, the
MIM process may enable much faster manufacturing of complex metal parts than
if such parts
were machined from solid metal. That said, the components of razor apparatus
100 may also be
fabricated using machining from a solid metal workpiece, liquid metal casting,
or any other
suitable technique.
100601 If MIM is chosen, any suitable feedstock may be employed. A
stainless steel powder
feedstock may be preferable, given that razor apparatus 100 would routinely be
exposed to
moisture during use. One possible feedstock choice would be 316L stainless
steel, which may
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have a post-sintering composition by weight of: < 0.03% carbon, 16.0 ¨ 18.0%
chromium, 10.0 ¨
14.0% nickel, 2.0¨ 3.0% molybdenum, <2.0% manganese, < 1.0% silicon, balance
iron.
100611 Alternatively, a substantially nickel-free stainless steel powder
feedstock may be
employed. One example of such a feedstock is BASFTM CatamoldTM PANACEA, which
may
have a post-sintering composition by weight of: < 0.2% carbon, 0.75 ¨ 0.90%
nitrogen, 16.5 ¨
17.5% chromium, < 0.1% nickel, 3.0 ¨ 3.5% molybdenum, 10.0 ¨ 12.0% manganese,
< 1.0%
silicon, balance iron. The use of PANACEA, heretofore unknown to the inventors
in the context
of manufacturing a razor apparatus, may present several advantages over other
types of stainless
steel. For example, PANACEA may provide increased resistance to bending or
breakage upon
.. impact (e.g., in the event that razor apparatus 100 is dropped). Moreover,
given that head 104 is
designed for extensive skin contact, the substantially nickel-free composition
of PANACEA may
be beneficial for those with nickel allergies. It is noted that in some
embodiments, the
components of head 104 may be fabricated using one type of material, whereas
other components
of razor apparatus 100 may be fabricated using a different material.
100621 FIG. 14 is a flow chart illustrating an embodiment of a method of
manufacturing a
razor apparatus. Operation begins in block 1400 with fabricating a lower
portion and an upper
portion of a head of a razor apparatus. Specifically, the lower portion and
upper portion are
fabricated to physically interface with each other, when assembled, at a front
region and a rear
region of the head. For example, the method may include fabricating lower
portion 120 and
.. upper portion 130 configured as described above, according to a MIM
process, machining, or any
other suitable fabrication process.
100631 Operation continues in block 1402 with assembling the lower portion
and the upper
portion of the head. When assembled, the lower and upper portions of the head
engage so that at
the front region of the head, the upper portion is physically supported by the
lower portion, and
the lower and upper portions of the head form an aperture for receiving a
single blade. For
example, lower portion 120 and upper portion 130 may be assembled as shown in
the preceding
figures according to the discussion above.
100641 FIG. 15 is a flow chart illustrating another embodiment of a method
of manufacturing
a razor apparatus. Operation begins in block 1500 with fabricating a lower
portion and an upper
portion of a head of a razor apparatus, where the lower portion includes a
number of retaining
posts. For example, lower portion 120 may include retaining posts 180 as
described in detail
above. As with the previously described method, this method may include
fabricating lower
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portion 120 and upper portion 130 according to a MIM process, machining, or
any other suitable
fabrication process.
100651
Operation continues in block 1502 with assembling the lower portion and the
upper
portion of the head. When assembled, the lower and upper portions of the head
form an aperture
for receiving a single blade. Moreover, each of the retaining posts is
configured to mate with a
respective recess in the single blade to retain the single blade within the
head upon insertion of
the single blade. Further, the retaining posts are spaced to retain the single
blade during use
while permitting the single blade to move in at least two dimensions during
use. For example,
lower portion 120 and upper portion 130 may be assembled to permit a small
degree of
movement of blade 200 as discussed above with respect to FIGs. 8-12.
100661
Although the discussion above has been presented with respect to a single
instance of
razor apparatus 100 in order to facilitate discussion, it is noted that any of
the features described
above __________________________________________________________________
specifically including the use of latches 145 and the configuration of
retaining posts
180¨may be used together or separately.
100671 It should be emphasized that the above-described embodiments are
only non-limiting
examples of implementations. Numerous variations and modifications will become
apparent to
those skilled in the art once the above disclosure is fully appreciated. It is
intended that the
following claims be interpreted to embrace all such variations and
modifications.
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