Patent Publication Number: US-3874079-A

Title: Auxiliary trimmer assembly for an electric shaver

Description:
United States Patent 1191 Waters et a1.  
 [451 Apr. 1, 1975 [75] Inventors: Robert S. Waters; Donald L.  
 Shortlidge, both of Lancaster, Pa.  
 [73] Assignee: Schick Incorporated, Lancaster, Pa.  
 [22] Filed: June 6, 1974 [2]] Appl. No.: 477,021  
 3/1957 Germany 30/34.] 2/1960 United Kingdom 30/34.]  
 Primary Examiner-A1 Lawrence Smith Assistant Examiner-Marc R. Davidson [5 7] ABSTRACT An auxiliary trimmer head assembly for an electric shaver of the type having a close shaving head including a rounded perforated stationary comb member comprises a pair of trimmer blades arranged for sideby-side reciprocation. The upper margins of the blades are notched to form a precision cutting surface for long hair, and the lower margins are pivotally attached to the shaver housing to form a unitary blade assembly whereby the precision cutting surface can be positioned tangentially to the stationary comb member for assisting the close shaving head in cutting occasional long hairs, or away from the housing for precision trimming of sideburns, moustaches and other long hair areas.  
 13 Claims, 9 Drawing Figures FATENTED APR 3 I975 saw 1 or 4 PATENTEM I 1975 SHEET 2 OF 4 AUXILIARY TRIMMER ASSEMBLY FOR AN ELECTRIC SHAVER BACKGROUND OF THE INVENTION The invention is directed in general to electric shavers, and more particularly to an auxiliary trimmer head assembly which provides improved long hair cutting performance for such shavers.  
  Electric shavers ordinarily employ a close-shaving cutter head consisting of a thin stationary outer comb member having a plurality of small hair-sized openings and a reciprocatively driven inner cutter blade member which reciprocates in shearing relationship under the stationary outer comb. ln shaving, hair is pushed through the openings in the outer comb and sheared off as the inner cutter blade passes beneath the openings.  
  While such conventional close-shaving cutter heads are satisfactory for cutting short hairs, they often are not satisfactory for cutting long hairs because the hair receiving apertures of the outer comb are so small that the long hairs tend to bend over and lie flat instead of being pushed through the openings. If the comb is formed with larger openings to accommodate long hairs, it becomes less satisfactory for shaving short hairs because the openings, which are normally dimensioned to permit the inner cutter blade to pass as close as possible to the skin without actually contacting the skin for the closest possible shave, then allow the inner cutter blade to contact the skin of the user, causing an unpleasant burn or skin irritation.  
  Another problem with close shaving cutter heads is that they are difficult to manipulate for precision trimming, as required for sideburns and moustaches. Accordingly, electric shavers are commonly equipped with an auxiliary trimmer head assembly specifically intended for long hair trimming. Heretofore such trimmer head assemblies have typically comprised a pair of elongated reciprocatively-driven cutter blades attached to the shaver housing at one end so as to be selectively extendable and retractable. A set of comblike cutting teeth were provided in shearing engagement at the projecting end of the cutter blades to provide a narrow well-defined long-hair cutting surface. While the extended cutter blades could be manipulated with precision around sideburns and moustaches for trimming purposes, they were generally ineffective in aiding the close shaving head in cutting occasional long hairs found on closely shaved portions of the face and neck. To cut such occasional long hairs it was necessary to extend the trimmer blades and individually trim each hair, which was a tedious, time-consuming operation.  
  Accordingly, the need has developed for an auxiliary trimmer head assembly for an electric shaver which efficiently performs the dual functions of aiding the close shaving head in cutting occasional long hairs, and of accurately trimming sideburns and moustaches. It is to such an auxiliary trimmer head assembly that the present invention is directed.  
  Accordingly, it is a general object of the present invention to provide a new and improved auxiliary trimmer assembly for an electric shaver or the like.  
  It is a more specific object of the present invention to provide a new and improved auxiliary trimmer assembly for assisting the close shaving head in cutting occasional long hairs, and for trimming sideburns and moustaches.  
  It is another object of the present invention to provide a new and improved auxiliary trimmer assembly which can be positioned for either assisting the close shaving head of the shaver or for trimming moustaches and sideburns.  
  It is another object of the present invention to provide a new and improved trimmer assembly for an electric shaver which can be positioned in close proximity to the close shaving head of the shaver for assistance thereto in cutting occasional long hairs, or in an outwardly projecting position from the shaver housing for maximum convenience and precision in trimming sideburns and moustaches.  
  It is another object of the present invention to provide anew and improved auxiliary trimmer assembly for an electric shaver which is pivotally mounted to the shaver housing, and which is continuously powered and adjustable between an outwardly extending sideburn and moustache trimming position and a retracted close shaving position immediately adjacent the comb of the close shaving head of the shaver whereby it may be adjusted for optimum performance under a variety of shaving conditions.  
 SUMMARY OF THE INVENTION The invention is directed to an electric shaver of the type having a housing, a power driven actuating member contained within the housing, and a cutter head of the close-shaving type comprising a fixed perforated comb member and a cutter blade reciprocatively driven by the actuating member, to an auxiliary long hair trimmer-head assembly which includes a trimmer blade assembly comprising first and second trimmer blades having spaced cutting teeth at one end and arranged for relative reciprocation, amd means for maintaining the trimmer blades in operative engagement. Means are provided for pivotally mounting the trimmer blade assembly to the housing whereby&#39;the trimmer blade assembly can be pivoted between a retracted position, wherein the cutting teethare disposed adjacent the comb member of the close-shaving cutter head, and an extended position, wherein the cutter teeth project away from the housing. Drive means are further provided for reciprocatively driving the second trimmer blade in the retracted and extended positions to enable the trimmer blade assembly to assist the close-shaving head in cutting long hairs in the retracted position, and to serve as a precision long-hair trimmer in the extended position.  
 BRIEF DESCRIPTION OF THE DRAWINGS The features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The invention, together with the further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which:  
  FIG. 1 is a perspective view of an electric shaver incorporating an auxiliary trimmer assembly constructed in accordance with the invention.  
  FIG. 2 is a top plan view of the electric shaver of FIG. 1.  
  FIG. 3 is an enlarged side elevational view of the head portion of the electric shaver of FIG. 1.  
  FIG. 4 is a side elevational view of the electric shaver of FIG. 1 partly broken away to show the principal components of the close-shaving head and head-drive assembly.  
  FIG. 5 is an enlarged side elevational view, partially in cross section, of the head portion of the electric shaver in FIG. 1.  
  FIG. 6 is a cross-sectional view taken along lines 6-6 of FIG. 2.  
  FIG. 7 is an enlarged side elevational view, partially broken away, of the head portion of the electric shaver showing the auxiliary trimmer assembly in its fully extended position.  
  FIG. 8 is a top plan view of the auxiliary trimmer assembly and its associated drive components taken along lines 88 of FIG. 7.  
  FIG. 9 is an exploded view of the principal components of the auxiliary trimmer assembly.  
 DESCRIPTION OF THE PREFFERRED EMBODIMENT While the auxiliary trimmer assembly of the present invention can be fabricated with blades of various shapes and sizes for use in conjunction with various types of electric shavers, it finds particular utility in connection with an electric shaver of the type having a close shaving cutter head consisting of a reciprocatively driven inner cutter blade urged into contact with the under surface of a rounded perforated stationary comb, such as the electric shaver 10 shown in FIG. 1.  
  Referring to the Figures in greater detail, and particularly to FIGS. 13, the electric shaver 10 is seen to comprise a housing 11 having a generally rectangular body portion and a rounded head portion. The head portion includes a comb frame 15 pivotally attached to housing 11 at one end by a hinge pin 16. The other end of the comb frame is latched to housing 11 by a comb release button 17, which allows that end to be unlatched by the user and the comb frame to be pivoted to the open position shown in FIG. 4. A comb 18, which may be fabricated from thin perforated metal foil or other suitable material, is seated in the rounded top portion of the comb frame 15 so that its perforated surface is exposed through the rectangular opening provided in the comb frame and assumes the rounded shape of the frame for optimum contact with the skin surface to be shaved. An ON-OFF power switch 19 may be provided at one side of the body portion for controlling the application of electrical power to the shaver.  
  Referring to FIG. 4, wherein the comb frame 15 has been pivoted to its open position, the close-shaving head of shaver 10 is seen to include an internal cutter blade assembly 22 consisting of a plurality of individual crescent-shaped cutter blades 23 arranged in a vertical spaced-apart relationship .with their cutting edges facing upwardly. When the comb frame 15 is closed, as shown in FIG. 5, the cutting edges of these blades bear against the underside of comb member 18 to achieve the desired close shaving action. The blade assembly 22 is removably mounted on a stem 24, which extends through a transversely elongated slot 25 in the shaving head and into engagement with a slidably mounted actuator member 26. A pair of opposed inwardly facing channels 27 and 28 are moulded into opposite sides of housing 11 to define a transversely-aligned reciprocative path for actuator member 26.  
  In operation, actuator member 26 is reciprocatively driven along the path defined by channels 27 and 28 by means of an eccentric cam 30 which is carried on the shaft 31 of a drive motor 32. Cam 30 operatively engages the walls of a drive slot 33 molded into the bottom of actuator member 26 so that when the cam is rotated by motor 32 the actuator member is forced to reciprocatively slide back and forth. Since actuator member 26 is coupled by stem 24 to the cutter blade assembly 22, the individual cutter blades 23 contained thereon are reciprocatively driven against the underside of comb 18 while the motor is in operation.  
  Power for drive motor 32, which may be a conventional permanent-magnet type DC motor, is obtained by means of an electrical circuit which may include one or more rechargeable batteries 34 (FIG. 4), ON-OFF control switch 19, and a recessed connector 35 for establishing a connection to a power cord (not shown). The body portion of housing 11, which may consist of two half sections joined together, is preferably constructed of an electrically-insulated high-impact plastic and may include suitable internal ribbing for supporting the various electrical and mechanical drive compo nents of the shaver.  
  The comb frame 15, which, it will be recalled, holds comb 18 in position, is secured to housing 11 at its free end by means of a spring wire clip 36 which engages an appropriately positioned notch 37 provided on the comb frame. Spring clip 36 bears against release button 17, which enables the user to deform the spring to disengage the spring from notch 37 when it is desired to open the comb frame for cleaning, repair or replacement of the trimmer blade assembly 22.  
  Referring to FIG. 6, the individual cutter blades 23 of blade assembly 22 are held in position by three transversely extending tubular support members 40. These support members are joined at their ends to side plates 41 and at transversely-spaced locations near their midpoints to a pair of support plates 42. The support plates are in turn connected by pins 43 to a journal block 44. The cutter blades 23, support members 40, side plates 41, support plates 42, pins 43, and journal block 44 together comprise the aforementioned cutter blade assembly 22. The trimmer blade assembly 22 is mounted on stem 24 by means of a bore 45 provided on the bottom of journal block 44. This bore preferably includes a pair of opposed L-shaped keyways 46 on its inside surface which engage tab-like key surfaces 47 on stem 24 to achieve a positive locked-rotation engagement between the members. In practice, stem 24 may be hollow and a helical compression spring (not shown) may be provided therein to bias the blade assembly 22 upwardly.  
  Stem 24 is press-fit into a complementarily dimensioned bore 48 on the top of actuator member 26. An annular raised portion 50 may be provided on member 26 for the purpose of extending the depth of this bore, it being desirable to provide a secure torsion-free engagement between the actuator member and stem 24. Actuator member 26 is slidably mounted within channels 27 and 28 by means of integral raised runner potions 51 and 52 (FIG. 5) which are sized and spaced to fit within the channels. Restoring springs of flat spring steel (not shown) may be provided in a conventional manner on either side of actuator member 26 for smoother operation under varying load conditions.  
  To provide for trimming sideburns and moustaches, and to assist the close shaving head in cutting occasional long hairs in closely shaved portions of the face, shaver includes an auxiliary trimmer head assembly 60. Referring to FIGS. 6-9, trimmer head assembly 60 comprises a stationary outer blade 61, a reciprocatively driven inner blade 62, an inner blade carriage 63, and a wire indexing spring 64. The outer and inner blades are arranged side-by-side in sliding engagement to form a unitary blade assembly. This blade assembly is pivotally attached to housing 11 by means of a pair of hinge pins 65 which extend between respective ones of a pair of inwardly facing recesses (not shown) on housing 11 and respective ones of a pair of mounting tabs 66 formed on opposite sides of the bottom edge (FIG. 6) of blade 61. The bottom portion of blade 61 curves inwardly to enter housing 11 through an elongated aperture 67. The radius of this curvature preferably is constant and the recesses on housing 11 preferably establish a pivotal axis for the trimmer blade assembly 60 such that aperture 67 is fully occupied by blade 61 regardless of the position of the blade. This constantradius pivot arrangement prevents clippings or other foreign objects from entering the shaver housing through the aperture.  
  A precision long hair cutting surface 59 is formed at the top of trimmer blade assembly 60 by providing a series of spaced knife-edge notches 68 along the top marginal portions of trimmer blades 61 and 62. As the inner trimmer blade 62 is caused to reciprocate with respect to the outer trimmer blade 61, a shearing action is obtained between the knife edges of the notches which severs long hairs trapped therebetween. To protect the skin being shaved from the shearing action of the notches the cutting edge 59 is rounded by folding the top margin of outer blade 61 over the top margin of inner blade 62. This forms a channel 69 within which the top margin of blade 62 is received. The inner blade 62, which does not extend downwardly to the pivot point of outer blade 61, is held in position against the inside face of inner blade 61 by blade carriage 63, which may be formed of a suitable plastic material and which may be attached to blade 62 by means of bosses 70 on the outside face of the carriage which are forcefit into appropriately dimensioned recesses 71 on the blade. To maintain the two blades in accurate alignment, a pair of transversely-spaced inwardly facing alignment tabs 72 are struck from blade 60. These tabs extend through respective ones of a pair of elongated alignment slits 73 on blade 62 so that as the inner blade 62 reciprocates with respect to the outer blade 61, the tabs slide along the slits to maintain the blades in alignment.  
  Indexing spring 64 is provided to index the trimmer head assembly 60 in its extended and retracted positions. To this end the wire spring may include a&#39;pair of resilient coil portions 75 adjacent each end and a pair of spaced attachment portions 76 between the coil portions. The ends of wire spring 64 extend outwardly to engage inwardly-facing complementarily dimensioned spring retaining apertures 77 (FIG. 8) molded into housing 11, and the two attachment portions 76 of the spring are pivotally received within respective ones of a pair of inwardly rolled tabs 78 disposed along the bottom edge of the outer blade 61. This forms an over-thecenter spring biasing arrangement with respect to the pivot axis of blade 61 and housing 11, the spring action of the resilient coil portions serving to detent the trimmer blade assembly 60 in either its fully extended or its fully retracted positions. Since the indexing spring 64 is fully enclosed within housing 11, no potentially harmful exposed edges or additional shaver cleaning requirements are presented to the user by this indexing arrangement. A thumb actuator surface 79 may be provided for user convenience in extending and retracting the blade assembly.  
  Operating power is supplied to inner trimmer blade 62 by means of a pair of inwardly extending fingers 80 on carriage 63 which engage opposite sides of an outwardly extending actuator finger 81 on drive member 26. The lengths of fingers 80 and actuator finger 81 are such that the inner blade 62 is reciprocatively driven by the reciprocating drive carriage 26 in both the fully extended and fully retracted positions, and in all intermediate positions of trimmer blade assembly 60. The bottom margin of the drive carriage is held in position by a pair of fingers 82 which extend downwardly from the bottom edge of the carriage into sliding engagement with a pair of complementarily positioned support tabs 83 on the bottom edges of stationary outer blade 61.  
  Trimmer head assembly 60 performs the dual function of assisting the close-shaving cutter head in cutting long hairs, and of providing a means for precision trimming of sideburns or moustaches. Optimum assistance to the close shaving head is realized by shaping the outer trimmer blade so as to bring the toothed long hair cutting surface in close proximity to comb 18 just below its point of maximum curvature, so that when shaving in close-shaven areas where long hairs may occasionally be encountered, such as on the neck and under the chin, the comb surface of the close-shaving head will first be brought into contact with the skin, followed immediately by the retracted long hair trimmer. Optimum precision trimming is realized when the auxiliary trimmer head assembly is fully extended so as to space the long hair cutting edge away from the shaver body where it can be seen and accurately positioned with respect to sideburns, moustaches, or other shaving areas requiring precision trimming.  
  It will be appreciated that the cutter blades of the auxiliary trimmer assembly may have other sizes and shapes, and that alternate drive arrangements may be provided, such as a resilient link member between the shaver drive member and the inner trimmer blade. Furthermore, since the trimmer assembly requires a minimum number of additional components and is simple in design and construction, it can be economically incorporated in existing shaver designs with minimum modifications to the shaver. While the trimmer assembly has been shown only in conjunction with a motordriven type electric shaver, it will be appreciated that it can be incorporated in vibrator type electric shavers as well.  
  While a particular embodiment of the invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the invention.  
 We claim:  
  1. In an electric shaver of the type having a housing, a power-driven actuating member contained within said housing, and a cutter head of the close-shaving type comprising a fixed perforated comb member and a cutter blade reciprocatively driven by said actuating member; an auxiliary long hair trimmer head assembly comprising, in combination:  
 a trimmer blade assembly comprising first and second trimmer blades having spaced cutting teeth at one end and arranged for relative reciprocation, and means for maintaining said trimmer blades in operative engagement;  
 means for pivotally mounting said trimmer blade assembly to said housing, said trimmer blade assembly having two operative positions, a retracted position, wherein said cutting teeth are disposed adjacent to and tangentially to said comb member of said close-shaving cutter head, and an extended position, wherein said cutter teeth project away from said housing; and  
 drive means for reciprocatively driving said second trimmer blade in said retracted and extended positions to enable said trimmer blade assembly to assist said close-shaving head in cutting long hairs in said retracted position, and to serve as a precision long hair trimmer in said extended position.  
  2. An electric shaver as defined in claim 1 wherein at least a portion of said perforated comb member of said close-shaving cutter head is approximately cylindrical in form.  
  3. An electric shaver as defined in claim 1 wherein said housing has substantially flat, opposed side walls, said close-shaving head is disposed at one end of said housing between said side walls, and wherein said trimmer blade assembly is pivotally mounted to one of said side walls.  
  4. An electric shaver as defined in claim 3 wherein spring means are provided for indexing said trimmer assembly in said extended and retracted positions.  
  5. An electric shaver as defined in claim 4 wherein said trimmer blade assembly is pivotally attached to said housing between the ends of said blades, said spring meanss comprise a wire spring having at least one resilient coil, said spring being pivotally attached at one end to the end of said first trimmer blade opposite said cutting teeth, and pivotally attached at its other end to said housing, said spring being dimensioned to establish an over-the-center spring bias condition with respect to the pivot axis of said trimmer blade assembly whereby said trimmer blade assembly is indexed in either said extended or retracted positions.  
  6. An electric shaver as defined in claim 1 wherein the toothed end of said first cutter blade is folded over to form a first channel along the inside top margin of said first trimmer blade, and wherein the toothed end of said second trimmer blade is slidably retained within said channel.  
  7. An electric shaver as defined in claim 6 wherein said long-hair trimmer head assembly further includes a carriage member, and said second trimmer blade is mounted thereon and is slidable therewith, and wherein at least a portion of said first trimmer blade is turned upwardly at its end opposite its toothed end to form a second channel for slidably receiving said carriage member, and wherein said carriage member includes inwardly projecting ears operatively engaged to said power-driven actuating member.  
 8. An electric shaver comprising, in combination:  
 a housing;  
 a power-driven actuating member contained within said housing;  
 a cutter head of the close-shaving type disposed at one end of said housing, said head including a fixed outer comb member and an inner cutter blade reciprocatively driven by said actuating member;  
 a trimmer blade assembly for cutting long hair including first and second cutter blades having spaced cutting teeth at one end and arranged for relative reciprocation, and means for maintaining said cutter blades in operative engagement;  
 means for pivotally mounting said trimmer assembly to said housing, said trimmer blade assembly having two operative position, a retracted position, wherein said cutting teeth are disposed adjacent to and tangentially to said fixed comb member of said close-shaving cutter head, and an extended position, wherein said cutting teeth project away from said housing; and  
 drive means for reciprocatively driving said second trimmer blade in said retracted and extended positions to enable said trimmer blade assembly to assist said close-shaving head in cutting long hairs in said retracted position, and to serve as a precision long hair trimmer in said extended position.  
 9. An electric shaver as defined in claim 8 wherein at least a portion of said comb is cylindrical in form.  
  10. An electric shaver as defined in claim 8 wherein said long-hair trimming head further includes a carriage member, and said second trimmer blade is mounted thereon and is slidable therewith, and wherein at least a portion of said first trimming blade is turned upwardly at its end opposite its toothed end to form a second channel for slidably receiving said carriage member, and wherein said carriage member includes inwardly projecting ears operatively engaged to said power-driven&#39;actuating member.  
  11. An electric shaver as defined in claim 1 wherein said cutting teeth overlie said comb member in substantially paralleling tangential relationship in said retracted position.  
  12. An electric shaver as defined in claim 11 wherein at least the end portion of said trimmer blade asembly having said spaced cutting teeth is curved to substantially conform to the outer surface of said comb member.  
  13. An electric shaver as defined in claim 8 wherein said cutting teeth overlie said comb member in substantially paralleling tangential relationship in said retracted position and wherein at least the end portion of said trimmer blade assembly having said spaced cutting teeth is curved to substantially conform to the outer surface of said comb member.