EP1140438B1

EP1140438B1 - Disposable cutting head for clippers

Info

Publication number: EP1140438B1
Application number: EP99966272A
Authority: EP
Inventors: Kim Laube
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-12-29
Filing date: 1999-12-15
Publication date: 2007-04-25
Anticipated expiration: 2019-12-15
Also published as: WO2000038889A1; AU2185300A; AU765077B2; DE69935930T2; CN1269621C; DE69935930D1; CN1334763A; EP1140438A1; JP2003535614A; EP1140438A4

Description

The invention relates to a clipper with a disposable cutting head according to the features of the preamble of claim 1.
There are currently in use a variety of devices for clipping, cutting and shearing hair and fur. These include devices commonly known as hair clippers or just clippers which in most instances modernly are powered by electric motors. Clippers as originally conceived and developed include cutting blades which are intended to be removed from the head of a clipper and sharpened to maintain the clipper device cutting performance. Such blades may be attached to the clipper head by screws and the like or may have clips, clamps or other retention means for attachment to the clipper.
More modernly clippers have incorporated heads which are designed to include replaceable blades which blades are not intended to be continually sharpened, but rather to be removed and disposed. US-A-2,722,742 discloses an example of such a device. Also, clipper head assemblies, which are disposable, have been designed for use with clippers. An example of a plastic disposable head assembly for clippers is disclosed in US-A-4,563,814.
The present invention provides an improved structure for a clipper head assembly with disposable blades. The entire assembly is such that the head assembly with blades is of the disposable type, but uses metal blades. if desired, the blades alone may be disposed and the head assembly reused; however, the structure is not intended for long wear and use. The head and blades are constructed such that the common problems encountered with existing removable/disposable heads and blades as for example heat retention in the blades and head and the catching and pulling of hair are minimized.
The support front edge of the base member of the present invention has no structure, such as comb teeth, which are under any portion of the cutting blades which comb teeth can catch and pull hair as, for example, in US-A-4,328,616 which has comb teeth under the cutting blade teeth such that when the two tooth elements are not in contact hair will be caught and pulled. In addition both cutting blades of the instant invention have a slightly concave shape, one relative to the other, along the entire blade longitudinal dimension to counter the tendency for blades to curl and separate which could cause the catching and pulling of hair as well as other problems. US-A-4,765,060 discloses a bend in the blade ends which may cause problems of separation as a result of a lack of a continuous concave shape along the longitudinal axis.
The WO-A-98 47 673, being the closest state of the art, discloses a hair-cutting apparatus having a base member, a lower and an upper cutting blade and a support for the lower blade as well as a spring member for the upper cutting blade.
Further state of the art is known from JP-A-7 031 754, US-A-5 579 581 and US-A-4 328 616.
One object of the present invention is an improved cutting head structure for Clippers which lowers friction and improves heat dissipation of the combination cutting head and blades to allow for a disposable clipper cutting head assembly. Another object is to reduce warpage of the head and/or blades during use in cutting to minimize pair pulling caused by hair becoming caught between the cutting blades rather than being cleanly cut. A further object is a disposable head and blade design which may be used with existing clip an combs. Another object is adaption of the cutting head for use with spring lock comb elements. A still further object is an upper cutting blade shoe structure for reduced friction wear of a clipper drive lug, which is usually plastic material, to which the upper blade shoe is engaged during clipper reciprocal drive operation. Another object is shielding of the clipper cavity which receives the cutting head to reduce the amount of hair or fur entering therein during a cutting operation. Yet another object is incorporation of protrusions in the base member to accommodate a variety of size of clipper blade socket mounting apparatus.
These objects are achieved by a clipper having the features of claim 1.
This inventive device is used to clip or cut hair, fur and the like of humans and animals. The new device provides for a disposable cutting head including blades to simplify in an economical manner the maintenance of a relatively sharp cutting instrument.
The cutting blades of the instant invention have indentations in the teeth to minimize heat build up and provide structural strength for the teeth. This is accomplished without the need for Cut outs in the tooth edge wall which is done for example in sheep cutting clipper blades to provide flexibility. Such Cut outs can cause loss of lubricants and also serve as a point that may catch and pull hair. In general, the new structure thus provides better cutting efficiency and minimum heat transfer to the subject being trimmed. The disposable system achieves improved performance in cutting efficiency and is constructed to be used with existing comb snap an devices.
In accordance with the description presented herein, other objectives of this invention will become apparent when the description and drawings are reviewed.

Brief Description of the Drawing

Figure 1: illustrates a perspective view of the head assembly with blades and outline of clipper.
Figure 2: illustrates a perspective view, exploded, of the head assembly and blades.
Figure 3: illustrates a perspective view, exploded, of an alternate embodiment of the head assembly and blades.
Figure 3A: illustrates a perspective view of an alternate embodiment of the head assembly with a deflector plate.
Figure 4: illustrates a bottom plan view of the upper cutting blade.
Figure 4A: illustrates a bottom plan view of an alternate embodiment of the upper cutting blade.
Figure 5: illustrates an elevation edge view of the upper cutting blade.
Figure 5A: illustrates an elevation edge view of an alternate embodiment of the upper cutting blade.
Figure 6: illustrates a top plan view of the upper cutting blade.
Figure 6A: illustrates a top plan view of the upper cutting blade with shoe lugs.
Figure 7: illustrates a side elevation cross-section view of the upper cutting blade taken at line 6-6.
Figure 8: illustrates a bottom plan view of .The lower cutting blade.
Figure 9: illustrates an elevation edge view of The lower cutting blade.
Figure 10: illustrates a top plan view of The lower cutting blade.
Figure 11: illustrates a side elevation cross-section view of The lower cutting blade taken at line 10-10.
Figure 12: illustrates a side elevation cross-section view of the head assembly with blades.
Figure 12A: illustrates a side elevation cross section view of the head assembly with blades and a spring member with a deflector plate.
Figure 13: illustrates a perspective view of the head assembly with blades and outline of an attached large tooth comb.
Figure 14: illustrates a perspective view of the head assembly with blades attachable to a modified tooth comb mounting apparatus.
Figure 15: illustrates a perspective view of the head assembly with blades attachable to an alternate tooth comb mounting apparatus.
Figure 16: illustrates a perspective view, exploded, of an alternate embodiment of the cutting head assembly for attachment of a comb element.
Figure 17: illustrates a side elevation cross-section view of an alternate embodiment of the head assembly with blades and spring mounting apparatus.
Figure 18: illustrates a bottom plan view of the alternate cutting head with spring mounting apparatus.
Figure 19: illustrates a perspective view of the tool for use with the spring mounting apparatus.

The disposable cutting head is basically a four element clip together assembly with a base, lower and upper cutting blades, and spring. The base serves as the support for the entire assembly and incorporates the attachment elements for retention to a clipper. The spring holds the elements together, forces the cutting blades together and includes the runner under which the upper blade slides. Attachment of a comb element may also be included. Alternate embodiments are described which use screw retention means for the spring and which use a spring lock for retention of comb elements. A plastic comb element for use with the spring lock retention means is incorporated. A deflector plate may be added to the spring structure to inhibit hair entering the clipper cavity.
Referring to Figures 1 through 15, disposable cutting head 1 has Base member 2 having a rear mounting portion 3 and Lower blade support portion 4. The rear mounting portion 3 has an upstanding central bridge 5 with clipper 6 attachment lugs 7. The lower blade support portion 4 has posts 8 to retain Lower cutting blade 9. The lower blade support portion 4 support front edge 37 does not extend such that it protrudes under The lower cutting blade 9 Lower teeth 13. This alleviates the problem with existing cutting heads wherein the blade support element tends to catch and pull hair an the support base during cutting.
The lower cutting blade 9 is placed in Lower blade support portion 4 with apertures 14 receiving posts 8. The posts 8 inhibit horizontal motion of The lower cutting blade 9 relative to The lower blade support portion 4 yet allow vertical motion of The lower cutting blade 9. This provides for a vertical "floating" condition to maintain contact with the upper cutting blade 15 under conditions as for example when heating causes a blade to curl or warp. The posts 8 and apertures 14 also allow ease of blade replacement if such is desired and do not flatten the concave curvature of the blade as when fixed in place by permanent attachment in other cutting heads.
Lower cutting blade 9 has a generally planar rectangular shape with a recessed portion 10 the longitudinal length of the blade. There are ribs 11 formed in the recessed portion 10 to provide structural strength and to aid in minimizing heat build up. The lower cutting blade 9 also has indentations 12 or creases formed in The lower teeth 13 to reduce the sliding friction surface to minimize heat build up, to allow coolant flow and to provide structural strength.
The lower cutting blade 9 is placed in Lower blade support portion 4 with apertures 14 receiving posts 8. Upper cutting blade 15 is placed in sliding relationship an lower cutting blade 9 with lower teeth 13 parallel to upper teeth 16. In operation the upper cutting blade 15 slides longitudinally relative to the fixed lower cutting blade 9.
Upper cutting blade 15 is a generally planar rectangular shape with a recessed portion 17 formed along the longitudinal length of the blade which as illustrated in Figure 2 may be formed in a stamping operation to 'be of upwardly arched geometry in the lateral dimension. There are a plurality of upper teeth 16 forming the forward portion which may have indentations 12 similar to lower teeth 13. There is a groove 18 parallel with and spaced from the front toothed edge.
The rear edge 19 of the upper cutting blade 15 contains an enlarged recess 20 adapted to receive a drive lug 21 or other drive element of a clipper 6. There are a pair of shoes 22 formed in enlarged recess 20 to reduce friction wear caused by the reciprocal operation of clipper drive lug 21 operating to move upper cutting blade 15 in a sliding reciprocating motion across lower cutting blade 9. The shoes 22 preferably have rounded edges 38 to reduce wear of the drive lug 21. However, a suitable curved shoe lug 40 as illustrated in Figure 5A may also be used.
The spring member 23 is generally a U-shape element of spring steel or the like having opposed arms 24 shaped to fit the back edge 25 of the mounting portion 3 of base member 2. The opposed arms 24 may be retained an the base member 2 by arm apertures 26 engaging attachment posts 27. The opposing arms 24 curve upwardly from the base member 2 and project forward in an arched manner over the upper cutting blade 15 to terminate in a downwardly manner presenting a transverse, elongated runner 28 to engage the upper cutting blade 15 groove 18. The runner 28 would preferably have a plastic coating, sleeve or the like surface for ease in sliding motion with the groove 18.
The spring member 23 may also be retained an the base member 2 by a thread attachment method. An example is illustrated in Figure 3 wherein posts 27 are replaced with apertures 47 and the arm apertures 46 to receive screws 48. In addition, apertures 45 are included to allow the screws to pass through the opposed arms 24 upper portion. The threading of the screws 48 into the spring member 23 provides a means to adjust the tightness by which the spring member 23 is removably attached. Thereby the tension may be loosened when cutting fine or loose hair to reduce blade wear due to friction and heat; yet the tension may be increased when thick or matted hair to be cut.
The spring member 23 may also have an extended plate element or deflector plate 55 as best illustrated in Figures 3A and 12A to inhibit entry of hair or fur into the clipper cavity 41 during cutting operation.
In the preferred embodiment the lower cutting blade 9 and the upper cutting blade 15 are formed with a slightly concave shape along their longitudinal dimension one to the other in a plane parallel to the row of cutting teeth 13, 16 as in Figure 4 and 8. This serves to counter the tendency of cutting blades to curl and partially separate from each other from the ends 29, 30 inward when there is heat build up due to sliding friction during use. This warping can occur both in manufacture and during use. The upper cutting blade 15 may be further modified by forming a generally rectangular opening to serve as a heat aperture 70 to further facilitate heat dissipation.
The blades 9, 15 may be pressed, cut and/or punched in manufacture. When manufactured there is a ragged edge an the side of the blade exiting the cutting tool. For the preferred embodiment the ragged mating edges are at the top edge, that is, the edge between blades. Thus the blades need only be machined smooth an the mating edges and the jagged edges remain to aid in, cutting hair, but do not touch the subject's skin to cause injury. To aid in attaching the upper cutting blade 15 to the fixturing for manufacture, fixturing holes 44 may be provided.
Referring to Figure 13, a disposable cutting head 1 has attached a large tooth comb 31. The compact shape and the back-to-front width or lateral dimension of the assembly approximate more standard clipper heads and blades to allow attachment of standard comb attachments. Where a relatively flat comb attachment is desired, a metal or other strong structural material may be used as compared to the typical plastic comb 31. Figure 14 illustrates an example of a thin comb element 32 with comb teeth 33 having groove notch 34 to receive the front edge 36 of the disposable cutting head 1 and spring clip 35 back edge to engage and retain the thin comb element 32.
A variation of this spring force attachment is illustrated in Figures 15 through 18. In this case a back plate 51 replaces the spring clip 35 and side elements 65 are added. This provides a structure for the comb element 32 when a thin comb made of plastic or similar material is desired. A rivet indentation 66 may be provided if clearance is required when the comb element 32 is mounted. The back plate 51 has a slot 52 therein into which plate 53 protrudes by extension 56. The plate 53 has spring tabs 43 which engage springs 50 placed in spring cavities 49. The back plate 51 may be tapered in the portion 68 above the slot 52 for ease of inserting the extension 56 into the slot 52. The plate 53 is attached to the base member 2 by means of a rivet 61, screw or the like passing through aperture 60 and sliding aperture 62. Pressure an push tabs 42 compresses the spring 50 as the plate 53 is pushed against the force of the spring 50. This moves extension 56 to allow comb element 32 to be removed from or mounted an the cutting head 1. When thus mounted the groove notch 34 will engage the front edge 36 of the cutting teeth and when the plate 53 is released the extension 56 will engage the slot 52. A tool 63 with posts 64 may be provided as illustrated in Figures 16 and 19 to aid in pushing push tabs 42. The tool 63 with posts 64 may also have a blade or hex head for use in adjusting the tension for screws 48.
The base 2 may have a more exaggerated rounding of the corners 54 to aid the user in turning the clipper while cutting in confined areas such as animal limb joints and the like.
The base member 2 may also include protrusions 58 an the inside of attachment lugs 7 and in mounting cavity 57 which protrusions 58 are compressible. When the cutting head 1 is mounted to a clipper 6 a tongue is inserted in mounting cavity 57. The clipper tongues of various clippers 6 are not always of the same dimensions. The protrusions 58 accommodate a variety of sizes of tongues to reduce vibration from what otherwise would be a loose fit. The protrusions 58 an attachment lugs 7 serve a similar purpose when the cutting head 1 is attached to the clipper 6.
While the invention has been particularly shown and described with respect to the illustrated and preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the scope of the invention.

Claims

A clipper (6) with a disposable cutting head (1) comprising:
a base member (2) including a mounting portion (3) having an upstanding central bridge (5), a means for removable interlocking engagement with a clipper (6) and including a lower blade support portion (4) forward of the mounting portion (3);

the lower blade support portion (4) having a plurality of posts (8) in a recessed portion extending the longitudinal length of the lower blade support portion (4) ;

a lower cutting blade (9) having a plurality of lower teeth (13) on a forward edge thereof and a recessed portion (10) for assembly into the lower blade support portion (4) with the lower cutting blade (9) having a plurality of apertures (14) defined therein to receive the posts (8);

the lower teeth (13) formed with a plurality of indentations (12) therein;

an upper cutting blade (15) having a plurality of upper teeth (16) an a forward edge thereof and a recessed portion (17) including a groove (18) formed therein extending the longitudinal length of the upper cutting blade (15), and further including means for driven engagement by the clipper (6);

the upper cutting blade (15) being located opposed to and in contact with the lower cutting blade (9) when the disposable cutting head (1) is assembled wherein the upper cutting blade (15) and the lower cutting blade (9) are formed with a slightly concave shape one relative to the other along their longitudinal dimension parallel to the teeth (13, 16); and

a spring member (23) attached by a means for attachment to the base member (2),
characterized in that
said spring member (23) supports the upper cutting blade (15) in assembled longitudinal sliding fashion relative to and against the lower cutting blade (9) with a runner (28) in the groove (18).
The clipper according to claim 1, characterized in that the upper teeth (16) are formed with a plurality of indentations (12) therein.
The clipper according to claim 1 or 2, characterized in that the lower cutting blade (9) has a plurality of ribs (11) defined therein in the recessed portion (10).
The clipper according to one of the preceding claims, characterized in that the upper cutting blade (15) means for driven engagement is a rear edge (19) having an enlarged recess (20) defined therein on two edges of which a pair of shoes (22) are formed.
The clipper according to claim 4, characterized in that each shoe (22) has a round edge at the contact surface with a clipper drive lug (21).
The clipper according to one of the preceding claims, characterized in that the lower cutting blade (9) and the upper cutting blade (15) are formed with the lower teeth (13) and the upper teeth (16) ragged edges formed during the manufacturing process to be oriented in the direction of the opposed lower cutting blade (9) and the upper cutting blade (15) when assembled.
The clipper according to one of the preceding claims, characterized in that the lower blade support portion (4) at a support front edge (37) thereof does not protrude under the lower teeth (13).
The clipper according to one of the preceding claims, characterized in that the spring member (23) means for attachment to the base has a pair of apertures (26, 45) therein in a pair of opposed arms (24) upper portion and has a pair of threaded apertures (26, 46) therein in the opposed arms (24) lower portion, and a pair of screws (48) passing through the opposed arms (24) upper portion and the base (2) with the screws (48) threadably engaged with the threaded apertures (46).
The clipper according to one of claims 1 to 7, characterized in that the spring member (23) means for attachment to the base (2) has a pair of attachment posts (27) on the underside thereof and in that the spring member (23) has a pair of apertures (26) therein in a pair of opposed arms (24) lower portion wherein the attachment posts (27) pass through the apertures (26).
The clipper according to one of the preceding claims, characterized in that the base (2) at a back edge (25) has rounded corners.
The clipper according to one of the preceding claims, characterized in that there is a deflector plate (55) attached to the spring member (23) in position to partially cover a clipper cavity (41).
The clipper according to one of the preceding claims, characterized in that the upper cutting blade (15) has a heat aperture (70) formed therein.
The clipper according to one of the preceding claims, characterized in that the upper cutting blade (15) has fixturing holes (44) formed therein.
The clipper according to one of the preceding claims, characterized in that the base member (2) has a pair of attachment lugs (7) with a protrusion (58) an each.
The clipper according to one of the preceding claims, characterized in that the base member (2) has a mounting cavity (57) with a plurality of protrusions therein (58).
The clipper according to one of the preceding claims, characterized in that the base member (2), has a plate (53) slidably engaged on a bottom thereof, the plate (53) having an extension element (56) rearward of the base member (2), a cavity (49) formed in the base (2) member with a spring (50) inserted therein; the plate (53) having a spring tab (43) which engages the spring (50), and a means (42) to press the plate (53) against the force of the spring (50).
The clipper according to claim 16, characterized in that the means to press is a push tab (42) attached to the plate (53).
The clipper according to claim 17, characterized in that a tool (63) is used to press the push tabs (42).
The clipper according to claim 16, characterized in that the means for slidable engagement is the plate (53) having a slide aperture (62) therein and a rivet (61) attaches the plate (53) through the slide aperture (62) to the base element (2).
The clipper according to one of the preceding claims, characterized by the upstanding bridge (5) having a mounting cavity (57) therein and a pair of attachment lugs.
The device according to claim 20, characterized in that each attachment lug has a protrusion (58) on the inside surface thereof.
The device according to claim 20 or 21, characterized in that the mounting cavity (57) has a plurality of protrusions (58) therein.