Patent Description:
According to the invention there is provided a hair clipper with a housing, a drive assembly, a blade set, and a drive cap. The housing includes an upper housing coupled to a lower housing each having an inner surface. The blade set is coupled to the drive assembly and includes an outer blade and an inner blade that oscillates over the outer blade. The drive cap is coupled to the upper housing with a snap fastener located on the inner surface of the upper housing that removably couples with a snap detent on an inner surface of the drive cap. The drive cap partially surrounding the drive assembly to provide a barrier that prevents debris from entering the drive assembly. The drive cap further comprises protrusions that couple with voids on the upper housing, and extensions on one of the drive cap and the upper housing that interface with slots on the other of the drive cap and the upper housing to seal the drive cap onto the upper housing,
Alternative exemplary embodiments relate to other features and combinations of features as may be generally recited.

This application will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements in which:.

Referring generally to the figures, various embodiments of a drive cap are shown. The drive cap couples to the upper housing and lower housing to create a hair clipper outer body that surrounds the drive assembly. The removable cover or drive cap covers the forward portion of the drive assembly (e.g., motor). Past embodiments of the drive cap interconnect the drive cap to the upper housing or lower housing with fasteners or screws. Fasteners change the look and feel of the hair clipper outer body and require screwdrivers to remove the drive cap. Removing the drive cap is often useful to access the drive assembly for cleaning and maintenance.

Applicant has found that using snap fasteners configured to couple with a detent on the inner sides of the drive cap and upper housing can provide a secure method of coupling the drive cap to the outer body. Snap fasteners create a secure joint that appears seamless on the outer body of the hair clippers. In addition, the joint does not require fasteners or other hardware to remove or replace the drive cap. Various additional lips and protrusions slidably guide and hold the drive cap in position to securely couple the drive cap to the upper housing and lower housing. No additional hardware to join or remove drive cap is used other than snap fasteners and orienting projections and slots. Such an assembly gives a smooth, transition-free appearance to the outer body of the hair clippers.

<FIG> illustrates a hair cutter or clipper <NUM> comprising a cutting blade set or assembly <NUM>. Blade assembly <NUM> is driven by a drive assembly <NUM> (illustrated in <FIG>). Hair clipper <NUM> includes a body or an outer body <NUM> that surrounds drive assembly <NUM> and is attached to cutting blade assembly <NUM>. Outer body <NUM> includes a lower housing <NUM>, an upper housing <NUM>, and a removable cover or drive cap <NUM>. Lower and upper housings <NUM> and <NUM> and drive cap <NUM> couple to surround, or partially surround, drive assembly <NUM> and/or a battery or electrical storage device. Drive cap <NUM> is located adjacent to blade assembly <NUM> and in enclosing relation to drive assembly <NUM>. Drive cap <NUM> partially surrounds drive assembly <NUM> to provide a barrier that prevents debris from entering drive assembly <NUM>. Lower housing <NUM>, upper housing <NUM>, and drive cap <NUM> include resilient structures that extend into or from drive cap <NUM> to removably connect drive cap <NUM> to outer body <NUM>. Drive cap <NUM> partially surrounds drive assembly <NUM> and provides a protective barrier. Removal of drive cap <NUM> exposes parts of blade assembly <NUM> and drive assembly <NUM>.

Lower housing <NUM> and upper housing <NUM> are coupled through any suitable manner, such as by screws, rivets, spot welds, adhesives, fasteners, or other means. In some embodiments, lower housing <NUM> couples to upper housing with one or more snap fasteners <NUM> and/or snap detents <NUM>. In some embodiments, one of lower or upper housing <NUM> or <NUM> has snap fastener <NUM> on an inner surface <NUM> (e.g., inner surface 33a on lower housing <NUM> or inner surface 33b on outer housing <NUM>) and the other of lower or upper housing <NUM> or <NUM> has snap detent <NUM> on the other inner surface <NUM>. Snap fastener <NUM> and snap detent <NUM> are coupled on inner surfaces <NUM> of lower and upper housings <NUM> and <NUM> to releasably couple housings <NUM> and <NUM>. Lower housing <NUM> and upper housing <NUM> are elongate shaped and form a semi-cylindrical shape in the direction transverse to the direction of elongation. In some embodiments, outer body <NUM> and its component parts, are a relatively rigid plastic or another polymer and generally hollow.

Lower housing <NUM> includes an outer surface <NUM>, an inner surface 33a, a forward end <NUM>, and a rearward end <NUM>. Lower housing <NUM> has lateral edges <NUM> which extend around the periphery of lower housing <NUM>. Similarly, upper housing <NUM> includes an outer surface <NUM>, an inner surface 33b (<FIG> and <FIG>) a forward end <NUM>, and a rearward end <NUM>. Upper housing <NUM> has lateral edges <NUM> which extend around the periphery of upper housing <NUM>. Lateral edges <NUM> of upper housing <NUM> are configured to couple with lateral edges <NUM> of lower housing <NUM>. Lateral edges <NUM> of lower housing <NUM> include respective forward end segments <NUM> which extend forwardly beyond the forward end <NUM> of upper housing <NUM>.

<FIG> illustrates a top view of blade assembly <NUM> and the connection between drive cap <NUM> and upper housing <NUM>. Blade assembly <NUM> includes an outer, lower, or stationary blade <NUM> and an inner, upper, or translating cutting blade <NUM>. Cutting blade <NUM> is trapped between stationary blade <NUM> and the outer body <NUM>. Cutting blade <NUM> is captured between stationary blade <NUM> and outer body <NUM> and reciprocates over stationary blade <NUM>. Drive cap <NUM> has an inner surface 33c and an outer surface <NUM>. As illustrated, drive cap <NUM> includes protrusions <NUM> and snap fasteners <NUM>. Upper housing <NUM> includes two extensions <NUM> that interconnect upper housing <NUM> to drive cap <NUM>.

For example, protrusions <NUM> on drive cap <NUM> extend into upper housing <NUM> to releaseably engage drive cap <NUM> under upper housing <NUM> and orient snap fasteners <NUM> relative to snap detents <NUM> on drive cap <NUM> and/or housing <NUM> (or housing <NUM>). Protrusions <NUM>, snap fasteners <NUM>, and extensions <NUM> align drive cap <NUM> relative to lower and upper housings <NUM> and <NUM> and secure drive cap <NUM> into place. Thus, outer surfaces <NUM> and <NUM> of lower and upper housings <NUM> and <NUM> are continuous with outer surface <NUM> of drive cap <NUM>, creating a smooth outer body <NUM>. In this way, a smooth surface along outer body <NUM> is created without any transitions along lower housing <NUM>, upper housing <NUM>, and/or drive cap <NUM>.

As shown in <FIG>, blade assembly <NUM> is hingedly connected to the forward end <NUM> of lower housing <NUM> or outer body <NUM> for movement between an operating position (<FIG> and <FIG>) and a retracted position, shown in dotted outline. The retracted position provides access to drive cap <NUM> and facilitates removal of drive cap <NUM>. For example, pulling drive cap <NUM> away from upper housing <NUM> releases snap fasteners <NUM> and the joint slides along extensions <NUM> and protrusions <NUM>. In this way, the retracted position of blade assembly <NUM> facilitates removal of drive cap <NUM> from hair clipper <NUM>. The retracted position and removal of drive cap <NUM> enhances access to blade assembly <NUM> or drive assembly <NUM> for maintenance and/or cleaning. Any suitable mounting arrangement can be employed to couple blade assembly <NUM> to outer body <NUM>. A portion of upper housing <NUM> is broken away to show the inner surface <NUM> of upper housing <NUM>.

As illustrated in <FIG>, blade assembly <NUM> includes a stationary blade <NUM> and a movable or translating cutting blade <NUM> which laterally reciprocates or oscillates relative to stationary blade <NUM> to cut hair. Cutting blade <NUM> is coupled to and driven by drive assembly <NUM>, which interconnects cutting blade <NUM> to a drive motor <NUM> (<FIG>). Any conventional blade assembly <NUM> which is compatible with drive assembly <NUM> can be employed. Drive assembly <NUM> is fixedly supported within the hollow interior of the outer body <NUM>, e.g., by a pair of screws or adhesive. Drive assembly <NUM> operatively extends between a drive motor <NUM> and cutting blade <NUM> to reciprocate cutting blade <NUM> relative to stationary blade <NUM> in response to energization of motor <NUM>. In some embodiments, motor <NUM> receives electrical energy from an electrical storage device (e.g., battery or electrical outlet) to oscillate at least one blade in blade assembly <NUM>. In various embodiments, hair clipper <NUM> is either configured with a cord that plugs into an outlet or is cordless and contains a capacitor, battery, and/or other electrical storage device.

The forward end <NUM> of upper housing <NUM> terminates rearwardly of the forward end <NUM> of lower housing <NUM>. Forward end segments <NUM> extend between the forward end <NUM> of upper housing <NUM> to blade assembly <NUM> and form a surface to join drive cap <NUM> to lower housing <NUM>. Lower housing <NUM>, upper housing <NUM>, and/or drive cap <NUM> have one or more snap detents <NUM> and/or laterally extending forward edge portions or extensions <NUM> (<FIG>). Extensions <NUM> join the forward ends <NUM> of the lateral edges <NUM> of upper housing <NUM> to drive cap <NUM>. Extensions <NUM> join drive cap <NUM> to forward end segments <NUM> of lower housing <NUM>. The forward termination of upper housing <NUM> provides access to drive assembly <NUM> for cleaning, lubrication, and replacement without requiring tools. Upper housing <NUM> terminates rearwardly of forward end <NUM> of lower housing <NUM>, blade assembly <NUM>, and drive assembly <NUM> to provide access to these components when removed.

Referring to <FIG>, drive cap <NUM> extends forwardly from extension <NUM> on forward end <NUM> (<FIG>) of upper housing <NUM>. Drive cap <NUM> extends laterally between forward end segments <NUM> of lower housing <NUM>. Drive cap <NUM> seamlessly couples to lateral edges <NUM> of lower housing <NUM> and forward end <NUM> of upper housing <NUM> to form outer body <NUM>. For example, snap fasteners <NUM> extend from drive cap <NUM> and couple into snap detent <NUM> of upper housing <NUM>. In another example, drive cap <NUM> couples to lower housing <NUM> and/or upper housing <NUM> with one or more snap fasteners <NUM> on inner surface <NUM> (e.g., an inner surface <NUM> of drive cap <NUM>, lower housing <NUM>, and/or upper housing <NUM>) to snap detents <NUM> on an inner surface <NUM> (e.g., of lower housing <NUM>, upper housing <NUM>, and/or drive cap <NUM>). Snap fasteners <NUM> can couple drive cap <NUM> to lower housing <NUM> and/or upper housing <NUM>. Drive cap <NUM> provides a cover for the top of blade assembly <NUM> and extends rearwardly from blade assembly <NUM> to cover a portion of drive assembly <NUM>. Drive cap <NUM> includes a forward edge <NUM> adjacent to blade assembly <NUM> and a rearward edge <NUM> adjacent to forward end <NUM> of upper housing <NUM>. In some embodiments, each snap fastener <NUM> and each snap detent <NUM> is located on inner surfaces <NUM> of housings <NUM>, <NUM>, and/or drive cap <NUM>. For example, no snap fasteners <NUM> or detents <NUM> are located on outer surfaces <NUM>, <NUM>, and/or <NUM> of lower/upper housing <NUM>/<NUM> and drive cap <NUM>, respectively, are smooth.

With reference to <FIG>, drive cap <NUM> includes an inner surface 33c or interior <NUM> and an exterior <NUM> which, when drive cap <NUM> is assembled on outer body <NUM>, extends in smooth merging relation to outer surfaces <NUM> and <NUM> of lower and upper housings <NUM> and <NUM>, respectively. Drive cap <NUM> includes a rearward edge <NUM> which is located adjacent to forward end segments <NUM> of upper housing <NUM> when outer body <NUM> is assembled (see <FIG>). Drive cap <NUM> includes snap fasteners <NUM> to interconnect drive cap <NUM> with upper housing <NUM>. One or more protrusions <NUM> extend from drive cap <NUM> to facilitate the alignment and joining of drive cap <NUM> to upper housing <NUM> and/or lower housing <NUM>. One or more recesses <NUM> are formed in lateral edges <NUM> of drive cap <NUM>. Lateral edges <NUM> join drive cap <NUM> to forward end segments <NUM> of lower housing <NUM>. Recesses <NUM> in lateral edges <NUM> join with a lip projection on adjacent forward end segments <NUM> of lower housing <NUM>.

Rearward edge <NUM> and lateral edges <NUM> of drive cap <NUM> couple to forward end <NUM> of upper housing <NUM> and forward end segments <NUM> of lower housing <NUM>, respectively, to form outer body <NUM>. Drive cap <NUM> includes a forward edge <NUM> located adjacent to blade assembly <NUM>. Exterior <NUM> of drive cap <NUM> extends rearward from forward edge <NUM> and is rearwardly convergent and merges smoothly (without transitions) with outer surface <NUM> of lower housing <NUM> and outer surface <NUM> of upper housing <NUM> of outer body <NUM>. For example, lower and upper housings <NUM> and <NUM> and drive cap <NUM> have outer surfaces <NUM>, <NUM>, and <NUM> that merge, such that when lower and upper housings <NUM> and <NUM> are coupled to drive cap <NUM>, outer surfaces <NUM>, <NUM>, and/or <NUM> merge into a smooth exterior housing with curvilinear transitions (e.g., without acute or sharp angles).

Drive cap <NUM> and lower and upper housings <NUM> and <NUM> include resilient structures and/or cavities to secure drive cap <NUM>. The resilient structures and cavities include protrusions <NUM>, voids <NUM>, snap fasteners <NUM>, snap detents <NUM>, extensions <NUM>, slots <NUM>, recesses <NUM>, projections, and other structures or cavities to resiliently align and connect drive cap <NUM> in removable assembled relation to outer body <NUM>. These structures enable an aligned coupling of drive cap <NUM> within outer body <NUM> so that exterior <NUM> of drive cap <NUM> blends smoothly with outer surfaces <NUM> and <NUM> of lower and upper housings <NUM> and <NUM>. In addition, this configuration enables the nondestructive removal of drive cap <NUM> from outer body <NUM> without the use of tools. The removal of drive cap <NUM> facilitates access to drive assembly <NUM>. For example, removal of drive cap <NUM> facilitates lubrication, cleaning, and/or replacement of drive assembly <NUM>.

In addition, such structure includes, on lower housing <NUM>, upper housing <NUM>, and/or drive cap <NUM>, laterally spaced guiding and supporting extensions <NUM> or projections. Drive cap <NUM> may include one or more protrusions <NUM>. For example, a first protrusion <NUM> may extend downwardly or inwardly from laterally spaced lateral edges <NUM>. When drive cap <NUM> is connected to outer body <NUM>, protrusions <NUM> are releasably engaged under upper housing <NUM> and/or lower housing <NUM> to orient drive cap <NUM> with respect to outer body <NUM>. Similarly, drive cap <NUM> may include slots <NUM> to receive extensions <NUM> and/or voids <NUM> to receive protrusions <NUM>.

Upper housing <NUM> can include laterally spaced extensions <NUM> which extend forwardly beyond forward end <NUM> and from the underside or inside surface 33b of upper housing <NUM>. In addition, drive cap <NUM> can include protrusions <NUM> which extend inwardly from inside surface 33c or interior <NUM>. Protrusions <NUM> extend laterally outward in adjacent relation to voids <NUM>, thereby assisting in laterally locating drive cap <NUM> in proper relation to upper housing <NUM> to form outer body <NUM>.

In some embodiments, drive cap <NUM> is fabricated of the same plastic as is employed in lower and/or upper housings <NUM> and <NUM>. For example, drive cap <NUM> is constructed from a plastic material that is thicker than the same plastic material used in lower and upper housings <NUM> and <NUM>. The thickness and relatively short length of drive cap <NUM> and the otherwise non-semi-circular construction of drive cap <NUM>, as compared to lower and upper housing <NUM> and <NUM>, is such that drive cap <NUM> is resilient as compared to lower and upper housing <NUM> and <NUM>. In a specific embodiment, drive cap <NUM> and lower and upper housings <NUM> and <NUM> each comprise the same material, and drive cap <NUM> has a thickness that is greater than a maximum thickness of either lower or upper housing <NUM> or <NUM>. In this embodiment, drive cap <NUM> may be the same or a different material than lower and/or upper housings <NUM> and/or <NUM>.

In other embodiments, drive cap <NUM> is a different material and/or a thicker material to make drive cap <NUM> more resilient to fracture relative to lower and upper housings <NUM> and <NUM>. For example, drive cap <NUM> is made from a resilient thermoset polymer material and lower and/or upper housings <NUM> and <NUM> are formed from a thermoplastic material. In other embodiments, drive cap <NUM> is constructed from a thermoplastic and lower and/or upper housings <NUM> and <NUM> are formed from a thermoset material.

In use, when access to drive assembly <NUM> is desired for cleaning, lubrication, or replacement, drive cap <NUM> can be removed by manually manipulating the cover or drive cap <NUM> to release snap fasteners <NUM> located within snap detents <NUM>. In this way, the user can move drive cap <NUM> upwardly and away from lower housing <NUM> and forwardly from upper housing <NUM> without the use of a tool. Hinged connection of blade assembly <NUM> to outer body <NUM>, as described in reference to <FIG>, facilitates manual removal of drive cap <NUM> from outer body <NUM>. For example, blade assembly <NUM> is hingedly coupled to lower or upper housing <NUM> or <NUM> and releaseably rotated from an operating position to a retracted position. More particularly, displacement of blade assembly <NUM> to the retracted position, as shown in the dotted lines of <FIG>, enables improved grasp of drive cap <NUM> and facilitates manual removal from outer body <NUM>. In other words, the retracted position provides access to inner surface 33c of drive cap <NUM>.

With reference to <FIG>, drive cap <NUM> includes a snap fastener <NUM> that couples to a snap detent <NUM> in upper housing <NUM>. For example one of upper housing <NUM> and drive cap <NUM> has snap fastener <NUM> on inner surface <NUM> (e.g., inner surface 33b on upper housing <NUM> or inner surface 33c on drive cap <NUM>) and the other of upper housing <NUM> and drive cap <NUM> has snap detent <NUM> on its inner surface <NUM>. Snap fastener <NUM> and snap detent <NUM> on inner surfaces 33b and 33c cooperate to releasably couple upper housing <NUM> to drive cap <NUM>. In addition, upper housing <NUM> may include one or more extensions <NUM> configured to align with slots <NUM> in drive cap <NUM> to orient drive cap <NUM> with respect to upper housing <NUM>. Drive cap <NUM> includes one or more protrusions <NUM> configured to align with voids <NUM> in upper housing <NUM> to orient drive cap <NUM> with respect to upper housing <NUM>. As illustrated, drive cap <NUM> couples to upper housing <NUM> with various snap fasteners <NUM> and snap detents <NUM>. Similar coupling techniques can be used to join drive cap <NUM> to forward end segments <NUM> of lower housing <NUM>.

As illustrated in <FIG>, drive cap <NUM> is illustrated detached from upper housing <NUM>. The interior <NUM> of drive cap <NUM> includes one or more snap fasteners <NUM> configured to couple with a snap detent <NUM> in upper housing <NUM>. In some embodiments, upper housing <NUM> has one or more snap fasteners <NUM> configured to couple with a snap detent <NUM> in drive cap <NUM>. Upper housing <NUM> has one or more extensions <NUM> configured to couple with one or more surfaces or slots <NUM> on the rearward edge <NUM> of drive cap <NUM>. Similarly, drive cap <NUM> has one or more protrusions <NUM> configured to couple with one or more surfaces or voids <NUM> of the forward end <NUM> of upper housing <NUM>. Thus, the forward end <NUM> of upper housing <NUM> couples to the rearward edge <NUM> of drive cap <NUM>.

Upper housing <NUM> and drive cap <NUM> may have a mating recess <NUM> about lateral edges <NUM> configured to receive lower housing <NUM>. Edges <NUM> of upper housing <NUM> and lateral edges <NUM> of drive cap <NUM> may form a continuous recess <NUM> so that lower housing <NUM> can form a continuous lip projection to couple to upper housing <NUM> and drive cap <NUM>.

One or more fastener holes <NUM> in upper housing <NUM> may be configured to receive fasteners from lower housing <NUM> to join housings <NUM> and <NUM> and form outer body <NUM>. Drive cap <NUM> then slides into upper housing <NUM>. When snap fasteners <NUM> are received in lower and/or upper housing <NUM> or <NUM>, drive cap <NUM> completes outer body <NUM>. In addition, the various protrusions <NUM> and/or extensions <NUM> on lower housing <NUM>, upper housing <NUM>, and drive cap <NUM> ensure that the parts are correctly aligned and held firmly in place (e.g., hermetically seal) when snap fastener <NUM> secures into snap detent <NUM>. For example, extensions <NUM> align and/or couple with slots <NUM> on drive cap <NUM> to couple drive cap <NUM> to upper housing <NUM>. Similarly, protrusions <NUM> align and/or couple with voids <NUM> on upper housing <NUM> to couple and/or fluidly seal drive cap <NUM> seamlessly onto upper housing <NUM>. For example, a fluid seal may prevent air, water, or other fluids from entering the hollow interior of outer body <NUM>. The seal may be hermetic and/or fluid to make clippers <NUM> that are, e.g., water resistant. Similar protrusions <NUM>, voids <NUM>, snap fasteners <NUM>, snap detents <NUM>, extensions <NUM>, and/or slots <NUM> are envisioned for forward end segments <NUM> of lower housing <NUM>.

<FIG> illustrates drive cap <NUM> coupled to upper housing <NUM> and joined by snap fasteners <NUM>. Snap fasteners <NUM> enable secure non-permanent coupling of drive cap <NUM> and upper housing <NUM> with a smooth finish. Because no screws are used to couple upper housing <NUM> to drive cap <NUM>, the exterior surface along outer body <NUM> appears to have a smooth finish without any transitions. The joint is secured by protrusions <NUM>, snap fasteners <NUM>, and/or extensions <NUM>, but is not permanently joined. A user can remove drive cap <NUM> from upper housing <NUM> to clean, for example, motor <NUM> and/or other components.

<FIG> illustrates an isolated drive cap <NUM>. From this perspective, exterior <NUM> of drive cap <NUM> is visible. Snap fasteners <NUM> are visible from the rearward edge <NUM> of drive cap <NUM>. Protrusions <NUM> couple to voids <NUM> in upper housing <NUM> to help stabilize the joint and align drive cap <NUM> with respect to upper housing <NUM>. Extensions <NUM> on upper housing <NUM> couple with slots <NUM> to further stabilize and orient drive cap <NUM>. The forward edge <NUM> of drive cap <NUM> couples to the forward end <NUM> of upper housing <NUM>. Lateral edges <NUM> of drive cap <NUM> couple to the forward end segments <NUM> of lower housing <NUM> to complete outer body <NUM>. In some embodiments, lower and upper housings <NUM> and <NUM> and/or drive cap <NUM> are non-permanently joined by snap fasteners <NUM> coupled to snap detents <NUM>, protrusions <NUM> coupled to voids <NUM>, and extensions <NUM> coupled to slots <NUM>, such that lower and upper housings <NUM> and <NUM>, and drive cap <NUM> have no permanent joints to each other and are releasably coupled.

For purposes of this disclosure, the term "coupled" means the joining of two components directly or indirectly to one another. Such joining may be achieved with the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional member being attached to one another. Such joining may be permanent in nature or alternatively may be removable or releasable in nature.

It should be understood that the figures illustrate the exemplary embodiments in detail, and it should be understood that the present application is not limited to the details or methodology set forth in the description or illustrated in the figures.

Claim 1:
A hair clipper (<NUM>), comprising:
a housing including an upper housing (<NUM>) coupled to a lower housing (<NUM>), the upper housing (<NUM>) including an inner surface (33b);
a drive assembly (<NUM>);
a blade set (<NUM>) coupled to the drive assembly (<NUM>) and including an outer blade (<NUM>) and an inner blade (<NUM>) that oscillates over the outer blade (<NUM>); and
a drive cap (<NUM>) coupled to the upper housing (<NUM>) with a snap fastener (<NUM>) located on the inner surface (33b) of the upper housing (<NUM>) that removably couples with a snap detent (<NUM>) on an inner surface (33c) of the drive cap (<NUM>), the drive cap (<NUM>) partially surrounding the drive assembly (<NUM>) to provide a barrier that prevents debris from entering the drive assembly (<NUM>),
characterized in that the drive cap (<NUM>) further comprises protrusions (<NUM>) that couple with voids (<NUM>) on the upper housing (<NUM>), and extensions (<NUM>) on one of the drive cap (<NUM>) and the upper housing (<NUM>) that interface with slots (<NUM>) on the other of the drive cap (<NUM>) and the upper housing (<NUM>) to seal the drive cap (<NUM>) onto the upper housing (<NUM>).