The present invention relates to hand held clippers for trimming hair and the like. More particularly, the present invention is related to seals for sealing a gap in an electric hand held clipper housing, as well as to clippers having a seal for sealing a housing gap.
Hand held clippers for trimming and shearing hair are generally known in the art. Conventional clippers typically include a housing that contains a motor, with the motor drivingly attached to a blade assembly for trimming or cutting the hair. The blade assembly typically has a reciprocating blade that cooperates with a fixed blade to trim or clip hair. The housing may have a front opening for passing an operative portion of the fixed and moving blades. A gap generally exists between the blade assembly and the housing. This gap can have several disadvantages associated with it.
For example, the gap may be proximate the operating portion of the blades and therefore be regularly exposed to cut portions of hair. The hair cuttings can enter the clipper housing through the gap and can be harmful to operation of the clipper. Cuttings can become tangled between the moving and non-moving blade, increase friction between the two blades, and over time may even shorten the stroke of the moving blade. Hair cuttings can likewise interfere with operation of the motor and its linkage to the moving blade. Further, hair cuttings can trap dust, grease, and other debris. These and other problems with hair cuttings are particularly troublesome because hair cuttings are notoriously slow to decompose and difficult to disengage once entangled. These problems can result in the need for frequent disassembly and cleaning of clippers, and if not effectively addressed can lead to a substantially shortened clipper service life.
Some solutions to these problems have been proposed in the past. To date, however, the proposed solutions have been deficient. For example, a proposed solution has been to secure an insert in the gap using an adhesive. Often a foam insert has been used. While such foam inserts may limit entry of hair into the clipper housing for a period of time, experience has suggested them to be limited in effectiveness and service life. For example, some foam inserts tend to disintegrate after a period of use and to thereby re-open the gap for entry of hair cuttings. Also, disintegration may cause small portions of the foam to come loose, with these small portions potentially interfering with clipper operation in the same way that the hair cuttings do. Other types of foam inserts have been known to collect hair in the foam itself to the extent that clipper operation may be impaired.
Further, the adhesive used to secure an insert of the prior art can have a tacky surface that may disadvantageously attract and retain hair cuttings. This can be particularly troublesome when the adhesive surface gradually becomes exposed over time as the foam disintegrates. Also, the adhesives holding some inserts in place tend to weaken with age and use, with the result that the insert may come loose.
In addition to these problems, foam inserts have proven to be difficult to replace. Because the service life of the foam insert is often considerably shorter than that of the clipper, consumers must be relied upon to replace the inserts. This is disadvantageous because many users either do not have the expertise to replace the inserts or are not willing to go to the effort of replacing the inserts. As a result, clippers with foam inserts may have less than satisfactory operation and may suffer a shortened service life.
Finally, some clippers are intended to be used with different blade sizes and geometries. For example, a particular clipper may be designed to fit any of a plurality of interchangeable blade assemblies of different sizes. Each of these blades may have different geometries that result in the gap between them and the housing to be different. Known inserts are generally not able to effectively accommodate these different gap sizes.
Unresolved problems in the art therefore remain.
One embodiment of the present invention is directed to a seal for a hand held hair clipper. In particular, an invention embodiment is a seal for use with a hand held clipper of the type that has a blade assembly and a housing, with a gap defined between the blade assembly and the housing. The seal includes a sealing portion that has a housing engaging side for engaging an interior surface of the clipper housing and an opposite blade engaging side for engaging at least a portion of the clipper blade assembly. A base portion is provided for attaching the seal to the housing.
An additional embodiment of the invention is directed to an electric hair clipper having a housing that contains an electric motor with a blade assembly operatively linked to the motor. The housing has an opening for passing a portion of the blade assembly. A gap is defined in the opening between the blade assembly and the housing. The housing has an interior surface and at least one interior boss. A molded thermoplastic seal is provided for sealing the gap, with the seal having at least one attachment tab for mating with the at least one boss.
Embodiments of the present invention thereby offer a solution to many of the otherwise unresolved problems of the prior art. For example, a molded thermoplastic seal offers advantages of resiliency and a longer service life than foam seals of the prior art. Additionally, attaching a seal of the invention to the clipper housing with an attachment tab solves many problems associated with the use of adhesives with prior art seals. Those skilled in the art will appreciate that embodiments of the present invention offer many other advantages and resolve other problems of the prior art, as will be better detailed below.
Turning now to
Two elongate projections 20 extend upwards from the housing engaging side 16 to define a channel therebetween. In the preferred embodiment, two projections 20 are located adjacent an edge 21 of the housing engaging side 16. However, it is contemplated that the location, number, and precise configuration of the projections 20 may vary to suit a particular application. For example, only one projection is contemplated. The preferred projections 20 are relatively thin and pliable, and thereby readily adapt to the particular size of a gap between a blade assembly and housing. For example, the projections 20 may be substantially compressed against a housing interior surface when a relatively large blade assembly is installed, and may be relatively un-compressed when a smaller blade assembly is present. Providing at least two projections 20 minimizes the chances of an ineffective seal.
Two arms 22 extend in a generally rearward direction from the base portion 14 opposite the edge 21 and each has a generally vertical wall 24 descending therefrom. An attachment formation, preferably having the shape of an attachment tab 26, is connected to the base of at least one and preferably both of the walls 24. The attachment formation or tab 26 is for releasably attaching the seal 10 to a housing interior surface. The tab 26 may be releasably engaged to hold the seal 10 in place when it is “pinched” between cooperating housing structures upon assembly of the housing. Additionally, a throughbore 28 extends through each of the attachment tabs 26 for engaging a housing boss.
Many alternative configurations to the tabs 26 and throughbores 28 will be obvious to those knowledgeable in the art. By way of example and not limitation, attachment means for releasably attaching the seal to the housing such as an open, U-shaped throughbore, clips, lugs, mating hooks and loops, and the like could readily be practiced with other embodiments of the invention. Also, it will be appreciated that the arms 22 are preferred only, and that other invention embodiments may have attachment means that are not connected to the seal via the arms 22.
The base portion 14 preferably has a generally arcuate shape in a cross direction, as best illustrated by
Also, the sealing portion 12 is preferably thinner than the base portion 14. A thicker base portion 14 provides for strength and some degree of rigidity useful for urging the sealing portion 12 into place. A thinner sealing portion 12 is preferable for providing greater flexibility and pliability so that different blade sizes and geometries can be effectively engaged. At least a portion 30 (best seen in
Referring now to
Referring now to
As best illustrated by
The seal shown generally at 110 effectively seals a gap defined between the blade assembly 64 and a perimeter edge of the housing opening 80. The seal 110 is generally consistent with the seal 10 illustrated in
When the spring 70 engages the blade engaging side 116 of the flexible seal 110, it urges the spring upwards into engagement with the housing interior surface 60. The base portion 114 is preferably thicker than the sealing portion 112. In combination with its cross direction arcuate shape, this advantageously provides the base portion 114 with a degree of stiffness useful to urge the more flexible sealing portion 112 into effective sealing position between the blade assembly 64 and the housing interior surface 60. A thinner sealing portion 112 is advantageous so that the sealing portion is relatively flexible to accommodate use of different interchangeable blade assemblies 64, as well as tolerances in blade assemblies 64 and housings. Preferably, the thickness of the seal 110 is generally tapered from a front side 121 of the thinner sealing portion 112 moving rearwards to a back edge of the thicker base portion 114.
As best shown by
Two arms 122 extend in a rearward direction from the base 114, with a generally vertical step or wall 124 at an end of the arms 122. An attachment formation or tab 126 is connected to the arms 122 and the wall 124 and is used to attach the seal 110 to the housing portion 52. Each of the attachment tabs 126 has a throughbore 128 for mating with one of the bosses 62, as best illustrated by
This attachment configuration has been discovered to offer several advantages over the prior art. For example, the present attachment configuration renders the seal 110 securely “trapped” in place once the housing is assembled. The chance of the seal 110 coming unattached is minimal. No tools, adhesives, screws or other fasteners are required for attachment. Replacement of the seal 110 is therefore a straightforward task.
Those skilled in the art will appreciate that the preferred seal and clipper embodiments described herein have been discussed for illustration purposes only. Other embodiments are of course possible within the scope of the invention. Indeed, those knowledgeable in the art will recognize equivalents to elements of the described preferred embodiment that are within the scope of the claimed invention.
Various features are set forth in the appended claims.
Number | Name | Date | Kind |
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3266143 | Rangus | Aug 1966 | A |
4991295 | Messinger | Feb 1991 | A |
Number | Date | Country | |
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20040010922 A1 | Jan 2004 | US |