Hair-cutting apparatus having a toothed cutting device, and toothed cutting device for a hair-cutting apparatus

Information

  • Patent Grant
  • 6308415
  • Patent Number
    6,308,415
  • Date Filed
    Friday, April 24, 1998
    26 years ago
  • Date Issued
    Tuesday, October 30, 2001
    22 years ago
Abstract
In a hair-cutting apparatus (1) and in a toothed cutting device (7) for a hair-cutting apparatus (1) the toothed cutting device (7) comprises a first toothed cutter (13) and a second toothed cutter (24), which lie against one another in the area of their cuttertooth rows (18, 25) and which each have at least one supporting limb (20, 21, 46, 47) in their areas which are remote from their cutter-tooth rows (18, 25), and of which one toothed cutter (24) carries an intermediate element (48) of a low-friction material, which comprises at least one intermediate element portion (49, 50) interposed between two facing supporting limbs (20, 46, 21, 47), and furthermore it has the advantageous feature that the at least one intermediate element portion (49, 50) of the intermediate element (48) carried by the one toothed cutter (24) has a smaller dimension in the toothed cutter direction (17) than the at least one supporting limb (20, 21) of the other toothed cutter (13), which last-mentioned limb 20, 21 faces the at least one intermediate element portion (49, 50).
Description




FIELDS OF THE INVENTION




The invention relates to an apparatus for cutting hairs, having a toothed cutting device which comprises a first toothed cutter with a first cutter-tooth row, which extends in a tooth row direction and comprises a plurality of cutter teeth, and a second toothed cutter with a second cutter-tooth row, which also extends in the tooth row direction and comprises a plurality of cutter teeth, and in which: (1) both toothed cutters are reciprocatingly drivable relative to one another in accordance with a given stroke; (2) both toothed cutters lie against one another in the area of their cutter-tooth vows and (3) both toothed cutters have at least one supporting limb each in their areas which, in directions transverse to the tooth row direction, are remote from the cutter tooth rows, which supporting limbs face one another pairwise and each have a given dimension in the tooth row direction, and (4) one of the two toothed cutters carries an intermediate element of a low-friction material, which intermediate element comprises at least one intermediate element portion interposed between two facing supporting limbs, via which portion the at least one supporting limb of this one toothed cutter acts upon the at least one supporting limb of the other toothed cutter and has a given dimension in the tooth row direction.




The invention further relates to a toothed cutting device for an apparatus for cutting hairs, which toothed cutting device comprises a first toothed cutter with a first cutter-tooth row, which extends in a tooth row direction and comprises a plurality of cutter teeth, and a second toothed cutter with a second cutter-tooth row, which also extends in the tooth row direction and comprises a plurality of cutter teeth, and in which: (1) both toothed cutters are reciprocatingly drivable relative to one another in accordance with a given stroke and in (2) both toothed cutters lie against one another in the area of their cutter-tooth rows (3) both toothed cutters have at least one supporting limb each in their areas which, in directions transverse to the tooth row direction, are remote from the cutter tooth rows, which supporting limbs face one another pairwise and each have a given dimension in the tooth row direction, and (4) of the two toothed cutters carries an intermediate element of a low-friction material, which intermediate element comprises at least one intermediate element portion interposed between two facing supporting limbs, via which portion the at least one supporting limb of this one toothed cutter acts upon the at least one supporting limb of the other toothed cutter and has a given dimension in the tooth row direction.




BACKGROUND OF THE INVENTION




An apparatus of the type defined in the first paragraph and a toothed cutting device of the type defined in the second paragraph are known, for example, from the document DE 26 46 818 A1. In the known apparatus and in the known toothed cutting device the two toothed cutters each have a single supporting limb in their areas which are remote from the rows of cutter teeth in directions transverse to the tooth row direction, which limbs have exactly the same dimension in the tooth row direction, which dimension corresponds to the overall length of each of the two cutters. In the known apparatus and in the known toothed cutting device the intermediate element of a low-friction material is connected to the non-drivable toothed cutter, which is stationary in operation. The intermediate element consists of a synthetic material. Owing to the fact that in the known apparatus and in the known toothed cutting device the intermediate element carried by one toothed cutter, i.e. the stationary toothed cutter, and the supporting limb of the other toothed cutter, i.e. the drivable toothed cutter, have the same dimensions in the tooth row direction, the successively recurring situation arises that in operation each of the two end portions of the supporting limb, which are spaced apart in the tooth row direction, come into contact with the intermediate element carried by the stationary toothed cutter, and is subsequently moved over the intermediate element up to and beyond the end of this element. This process leads to abrasion of the intermediate element by the end portions of the supporting limb of the drivable toothed cutter, as a result of which the toothed cutting device becomes soiled in the area of the two supporting limbs and the intermediate element, which abraded material may get between the intermediate element carried by the stationary toothed cutter and the supporting limb of the drivable toothed cutter, which gives rise to an undesirable increase of the friction between the intermediate element and the supporting limb of the drivable toothed cutter. Moreover, as a result of the abrasion of the intermediate element at its two ends the surface pressure between the intermediate element and the supporting limb of the drivable toothed cutter in the central area of these two parts of the toothed cutting device increases comparatively strongly, which also gives rise to an undesirable increase of the friction between these two parts.




SUMMARY OF THE INVENTION




An object of the invention is to preclude the above problems and to improve an apparatus of the type defined in the first paragraph and a toothed cutting device of the type defined in the second paragraph and provide an improved apparatus and a toothed cutting device, in which the friction between the intermediate element carried by one of the two toothed cutters and the supporting limb of the other one of the two toothed cutters does not increase even after a long time of use.




According to the invention, in order to achieve the above object an apparatus of the type defined in the first paragraph is characterized in that the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a smaller dimension in the toothed cutter direction than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion. As a result of these measures in accordance with the invention, it is achieved in a very simple manner and without any additional investment, i.e. at low cost, that during operation of the apparatus the ends of a supporting limb of a toothed cutter do not come into contact with an intermediate element portion of the intermediate element carried by a toothed cutter or, if there is contact, it is only to such a small extent that no abrasion of an intermediate element portion by the free ends of a supporting limb occurs. Consequently there is no abraded material of the intermediate element and thus no soiling of the toothed cutting device in the area of an intermediate element portion and of the supporting limb lying at the intermediate element portion. Thus possible drawbacks which would lead to an increased friction between a portion of the intermediate element and a supporting limb which cooperates with such a portion of the intermediate element are precluded.




In an apparatus in accordance with the invention having a toothed cutting device which comprises a first toothed cutter with a first cutter-tooth row, which extends in a tooth row direction and comprises a plurality of cutter teeth, and a second toothed cutter with a second cutter-tooth row, which also extends in the tooth row direction and comprises a plurality of cutter teeth, and in which both toothed cutters are reciprocatingly drivable relative to one another in accordance with a given stroke, in which both tooted cutters lie against one another in the area of their cutter-tooth rows, in which both toothed cutters have at least one supporting limb each in their areas which, in directions transverse to the tooth row direction, are remote from the cutter tooth rows, which supporting limbs face one another pairwise and each have a given dimension in the tooth row direction,




and in which one of the two toothed cutters carries an intermediate element of a low-friction material, which intermediate element comprises at least one intermediate element portion interposed between two facing supporting limbs, via which portion the at least one supporting limb of this one toothed cutter acts upon the at least one supporting limb of the other toothed cutter and has a given dimension in the tooth row direction, and wherein the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a smaller dimension in the toothed cutter direction than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion, it has further proved to be advantageous if, in addition, the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a dimension in the toothed cutter direction which is smaller by an amount equal to at least the stroke between the two toothed cutters than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion. This absolutely assures that abrasion of an intermediate element portion by the end portions of a supporting limb which cooperate with such an intermediate element portion is prevented.




In an apparatus in accordance with the invention features, it has further proved to be advantageous if, in addition, the intermediate element mainly consists of a polyamide in which silicon and polytetrafluoroethylene have been embedded. Tests have proved that such a construction of an intermediate element is particularly advantageous in comparison with intermediate elements of other materials because very low friction values have been obtained with such an intermediate element. It is to be noted that such an intermediate element may also be used in an apparatus in accordance with the invention wherein at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a dimension in the toothed cutter direction which is smaller by an amount equal to at least the stroke between the two toothed cutters than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion, as described above.




In an apparatus in accordance with the invention it has further proved to be advantageous if, in addition, the two toothed cutters each have two supporting limbs which are spaced apart in the tooth row direction. In comparison with a construction using a single supporting limb for each toothed cutter, such a construction has proved to be advantageous because lower friction values can be obtained with two comparatively short supporting limbs for each toothed cutter, which limbs are spaced apart in the tooth row direction. The feature wherein two toothed cutters each have two supporting limbs which are spaced apart in the tooth row direction may also be used in combination with any of the features described above.




In an apparatus in accordance with the invention having the characteristic features, wherein two toothed cutters each have two supporting limbs which are spaced apart in the tooth row direction, it has further proved to be advantageous if, in addition, the intermediate element is substantially U-shaped and comprises two intermediate element limbs, which extend substantially perpendicularly to the tooth row direction, and an intermediate element base, which extends substantially parallel to the tooth row direction and which interconnects the two intermediate element limbs, and the free end portions of the two intermediate element limbs are each interposed as intermediate element portions between two respective supporting limbs. Such a construction has proved to be advantageous for a highly simple mounting of the intermediate element portions between two facing pairs of supporting limbs.




In such an apparatus as just described, it has further proved to be advantageous if, in addition, the two intermediate element limbs of the U-shaped intermediate element are each integrally connected to a substantially U-shaped holder, in such a manner that a passage is formed between each of the intermediate element limbs and the holder which is integrally connected to the respective limb, and each passage is engaged by a supporting limb of the toothed cutter carrying the intermediate element, in order to hold the intermediate element. This guarantees that the intermediate element can be secured to the toothed cutter to be provided with the intermediate element.




According to the invention, in order to achieve the afore-mentioned object a toothed cutting device of the type defined in the second paragraph is characterized in that the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a smaller dimension in the toothed cutter direction than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion. Thus, for a toothed cutting device in accordance with the invention advantages are obtained which correspond to the advantages set forth hereinbefore for an apparatus in accordance with the invention having the characteristic features defined in the first paragraph.




The advantageous variants of a toothed cutting device in accordance with the invention, include the following embodiments:




(1) an apparatus wherein the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a dimension in the toothed cutter direction which is smaller by an amount equal to at least the stroke between the two toothed cutters than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion; and/or (2) wherein the intermediate element mainly consists of a polyamide in which silicon and polytetrafluoroethylene have been embedded; and/or (3) wherein the two toothed cutters each have two supporting limbs which are spaced apart in the tooth row direction; and/or (4) wherein the intermediate element is substantially U-shaped and comprises two intermediate element limbs, which extend substantially perpendicularly to the tooth row direction, and an intermediate element base, which extends substantially parallel to the tooth row direction and which interconnects the two intermediate element limbs, and the free end portions of the two intermediate element limbs are each interposed as intermediate element portions between two respective supporting limbs; and/or (5) wherein the two intermediate element limbs of the U-shaped intermediate element are each integrally connected to a substantially U-shaped holder, in such a manner that a passage is formed between each of the intermediate element limbs and the holder which is integrally connected to the respective limb, and each passage is engaged by a supporting limb of the toothed cutter carrying the intermediate element, in order to hold the intermediate element.




The afore-mentioned aspects as well as further aspects of the invention will be apparent from the embodiments described hereinafter by way of examples and will be elucidated by means of these embodiments.











The invention will now be described in more detail with reference to an embodiment shown in the drawings given by way of example, but to which the invention is not limited.





FIG. 1

is an oblique view of a hair-cutting apparatus in accordance with the invention provided with a toothed cutting device at one end face.





FIG. 2

is an exploded view of the toothed cutting device of the apparatus of FIG.


1


.





FIG. 3

is a plan view of the toothed cutting device of the apparatus of

FIG. 1

in its assembled condition.





FIG. 4

shows the toothed cutting device of

FIG. 1

in a sectional view taken on the line IV—IV in FIG.


3


.












FIG. 1

shows an apparatus


1


for cutting hairs, which is often also referred to as a hair trimmer. The apparatus


1


has a housing


2


which has been given a curved or angled shape in order to achieve an ergonomically favorable construction. In a dorsal area of the housing


2


a button


3


has been arranged, which button is slidable between a plurality of positions and which can be actuated to adjust a comb attachment, not shown, for the apparatus


1


between a plurality of different positions. The housing


2


of the apparatus


1


has two guideways adapted to receive guide members of such a comb attachment, of which only one guideway


4


is visible in FIG.


1


. In a ventral area of the housing


2


a further slide button


5


has been arranged, which is an on/off button which is slidable between two switch positions. By means of the further slide button


5


an electric drive motor accommodated in the housing


2


of the apparatus


1


can be switched on and switched off. The drive motor is adapted to drive a drive mechanism whose function will be described briefly hereinafter.




At the location of an end portion


6


of the housing


2


the apparatus


1


comprises a toothed cutting device


7


. The construction of the toothed cutting device


7


will be described in detail hereinafter with reference to

FIGS. 2

,


3


and


4


.




The toothed cutting device


7


comprises a cutter support


8


made of a synthetic material. The cutter support


8


has a substantially plate-shaped base


9


whose flat outer surface


9


A may be placed onto the skin of a user during use of the apparatus


1


. Three positioning projections


10


,


11


and


12


project from the inner side of the base


9


. A first toothed cutter


13


can be mounted onto these three positioning projections


10


,


11


and


12


, the positioning projections


10


,


11


and


12


then engaging three positioning holes


14


,


15


and


16


of the first toothed cutter


13


. In this way, the first toothed cutter


13


is stationarily mounted on the base


9


by means of the positioning projections


10


,


11


and


12


. Thus, the first toothed cutter


13


is a stationary toothed cutter, which is stationary during operation of the apparatus


1


and the toothed cutting device


7


.




The first toothed cutter


13


is made of steel, preferably chrome-steel, and has a cutter-tooth row


18


, which extends in a tooth row direction indicated by a double arrow


17


in

FIGS. 2 and 3

and which comprises a plurality of cutter teeth


19


,

FIGS. 2 and 3

showing only one of said cutter teeth


19


for the sake of simplicity. In its area which, in a direction transverse to the cutter tooth direction


17


, is remote from the cutter-tooth row


18


the first toothed cutter


13


comprises two supporting limbs


20


and


21


which are spaced apart in the cutter tooth direction


17


. In the assembled condition of the toothed cutting device


7


the supporting limbs


20


and


21


each bear on a supporting block


22


and


23


, respectively. The two supporting blocks


22


and


23


project from the base


9


of the cutter support


8


. In the tooth row direction


17


the two supporting limbs


20


and


21


of the first toothed cutter


13


have a given dimension, i.e. the length L


1


, as is indicated in FIG.


2


.




The toothed cutting device


7


comprises a second toothed cutter


24


. The second toothed cutter


24


is also made of steel, for example chrome-steel and comprises a second cutter-tooth row


25


, which also extends in the tooth row direction


17


and has a plurality of cutter teeth


26


. The second toothed cutter


24


is fixedly connected to a reciprocating bridge


27


made of a synthetic material and integrally connected to two mounting arms


30


and


31


via two integral hinges


28


and


29


. The mounting arms


30


and


31


each have a substantially semicircular end portion


32


and


33


, respectively. By means of the two end portions


32


and


33


the two mounting arms


30


and


31


are connected to two mounting projections


34


and


35


, which project from the base


9


of the cutter support


8


. The reciprocating bridge


27


further comprises a driving fork


36


in which a drive member of the afore-mentioned drive mechanism of the apparatus


1


engages, which drive mechanism can be driven by the electric drive motor of the apparatus


1


. The reciprocating bridge


27


can thus be driven by the drive motor of the apparatus


1


. When the reciprocating bridge


27


is driven the bridge


27


performs a reciprocating motion which is oriented substantially in the tooth row direction, the mounting arms


30


and


31


being stationary and the movability of the reciprocating bridge


27


being provided by the integral hinges


28


and


29


. By means of the reciprocating bridge


27


the second toothed cutter


24


, which is fixedly connected to this bridge, is reciprocatingly drivable relative to the stationary first toothed cutter


13


with a given stroke H. The stroke H can have a value of, for example, H=2.8 mm.




The toothed cutting device


7


further comprises a spring device


37


manufactured from a wire material and made of steel, preferably chrome-nickel steel but, alternatively, of spring bronze. The spring device


37


comprises a substantially U-shaped central portion


38


and two wound spring portions


39


and


40


, which adjoin the two limbs of the U-shaped central portion


38


and comprise a plurality of turns, as well as two bent end portions


41


and


42


which project from the respective spring portions


39


and


40


. The spring device


37


is constructed in such a manner that the central portion


38


, on the one hand, and the two end portions, on the other hand, tend to move towards one another. The central portion


38


of the spring device


37


is accommodated in a holder


43


which projects from the base


9


of the cutter support


8


. The two end portions


41


and


42


act on the reciprocating bridge


27


, the free ends of the two end portions


41


and


42


engaging in slots


44


and


45


in the reciprocating bridge


27


, as can be seen in FIG.


3


. By means of the spring device


37


, whose central portion


38


is accommodated in the holder


43


of the base


9


of the cutter support


8


and whose end portions


41


and


42


engage in slots


44


and


45


in the reciprocating bridge


27


, the two toothed cutters


13


and


24


are pressed towards one another with a given spring force, as a result of which the two toothed cutters


13


and


24


lie against one another in the area of their cutter-tooth rows


18


and


25


.




Similarly to the first toothed cutter


13


, the second toothed cutter


24


comprises two supporting limbs


46


and


47


which are spaced apart in the cutter tooth direction


17


. In the tooth row direction


17


the two supporting limbs


46


and


47


each have a given dimension, i.e. the length L


2


, as is indicated in FIG.


2


. The supporting limbs


20


and


21


of the first toothed cutter


13


face the supporting limbs


46


and


47


of the second toothed cutter


24


pairwise, i.e. facing pairs being formed by the supporting limbs


20


and


46


and by the supporting limbs


21


and


47


.




In the toothed cutting device


7


the second toothed cutter


24


, i.e. the reciprocatingly drivable toothed cutter


24


, of the two toothed cutters


13


and


24


carries an intermediate element


48


of a low-friction material. The intermediate element


48


comprises two intermediate element portions


49


and


50


interposed respectively between two facing supporting limbs


20


,


46


and


21


,


47


. The supporting limbs


46


and


47


of the second toothed cutter


24


respectively act upon the facing supporting limbs


20


and


21


of the first toothed cutter


13


via the respective intermediate element portions


49


and


50


. The two intermediate element portions


49


and


50


also have a given dimension in the tooth row direction


17


, i.e. the length L


3


, as is indicated in FIG.


2


.




In the apparatus


1


, i.e. in the toothed cutting device


7


of the apparatus


1


, the construction is advantageously devised in such a manner that each of the two intermediate element portions


49


and


50


of the intermediate element


48


carried by the second toothed cutter


24


has a smaller dimension in the tooth row direction


17


than the respective supporting limb


20


or


21


of the first toothed cutter


13


facing the relevant intermediate element portion


49


or


50


. In the present case the two lengths L


1


and L


3


have been selected in such a manner that the dimension in the tooth row direction


17


of each of the two intermediate element portions


49


and


50


of the intermediate element


48


carried by the second toothed cutter


24


is smaller than the supporting limb


20


or


21


of the first toothed cutter


13


which faces the relevant intermediate element portion


49


or


50


by an amount equal to at least the stroke H between the two toothed cutters


13


and


24


. In the case of a stroke H of the second toothed cutter


24


relative to the first toothed cutter


13


of, for example, H=2.8 mm the length L


1


of the two supporting limbs


20


and


21


can be, for example, 8.0 mm and the length L


3


can be, for example, 5.2 mm. However, in the present example the length can alternatively be 8.2 mm or 8.5 mm. In the last-mentioned example the length L


3


can alternatively be 5.0 mm or 4.7 mm. However, it is remarked explicitly that in said example with a length L


1


of 8.0 mm and a hub of 2.8 mm the length L


3


can also be 5.4 mm or even 5.6 mm without the advantages of the shorter dimension of the intermediate element portions


49


and


50


in relation to the supporting limbs


20


and


21


being lost.




With respect to the intermediate element


48


it is to be noted that this intermediate element


48


mainly consists of a polyamide in which silicon and polytetrafluoroethylene have been embedded. Such an intermediate element


48


exhibits particularly low friction values when its intermediate element portions


49


and


50


cooperate with the steel supporting limbs


20


and


21


of the first toothed cutter


13


made of steel. It is to be noted that it has proved to be very advantageous if the polyamide is polyamide 6.6. Furthermore, it has proved to be very advantageous if the intermediate element


48


consists mainly of polyamide, preferably polyamide 6.6, in which in addition to silicon and polytetrafluoroethylene glass beads, glass fibers or carbon fibers have been embedded.




It is to be noted also that the intermediate element


48


is substantially U-shaped and comprises two intermediate element limbs


51


and


52


, which extend substantially perpendicularly to the tooth row direction


17


, and an intermediate element base


53


, which extends substantially parallel to the tooth row direction


17


and which interconnects the two intermediate element limbs


51


and


52


. The free end portions of the two intermediate element limbs


51


and


52


are then each interposed as intermediate element portions


49


and


50


between, respectively, two supporting limbs


20


and


46


or


21


and


47


. As is further apparent from

FIG. 2

, the two intermediate element limbs


51


and


52


of the U-shaped intermediate element


48


are each integrally connected to a substantially U-shaped holder


54


or


55


, respectively, in such a manner that a passage


56


or


57


is formed between each of the intermediate element limbs


51


and


52


and the respective holder


54


or


55


, which is integrally connected to the respective limb. Each passage


56


or


57


is engaged by a supporting limb


46


or


47


of the second toothed cutter


24


carrying the intermediate element


48


in order to hold the intermediate element


48


. This construction has the advantage that the intermediate element


48


can simply be slid onto the two supporting limbs


46


and


47


of the second toothed cutter


24


in a direction transverse to the tooth row direction


17


, the two supporting limbs


46


and


47


being passed through the two passages


56


and


57


until the free ends of the supporting limbs


46


and


47


abut against stops


58


and


59


which project from the intermediate element limbs


51


and


52


at the ends of these limbs.




For the sake of completeness, it is to be noted that at its end which is remote from the two tooth rows


18


and


25


the plate-shaped base


9


of the cutter support


8


carries a member


60


which in the area of its free end carries a part of a pivotal device, whose other end is arranged on the housing


2


of the apparatus


1


. By means of this pivotal device the cutter support


8


and, consequently, the entire toothed cutting device


7


is pivotably connected to the housing


2


. In this way, the toothed cutting device


7


can be pivoted away from the housing


2


from the operating position shown in

FIG. 1

, in which the toothed cutting device


7


has been swung down onto the housing


2


of the apparatus


1


, into a cleaning position, not shown, in which the toothed cutters


13


and


24


as well as the other parts, such as the reciprocating bridge


27


, are accessible to permit cleaning.




In the apparatus


1


described in the foregoing and the toothed cutting device


7


described in the foregoing it is achieved in a particularly simple manner and substantially without any additional means, that the intermediate element portions


49


and


50


of the intermediate element


48


are always wholly in contact with the supporting limbs


20


and


21


of the first toothed cutter


13


, which prevents the supporting limbs


20


and


21


from causing abrasion of the intermediate element


48


in the area of the intermediate element portions


49


and


50


. This precludes soiling of the toothed cutting device


7


in the area of the supporting limbs


20


and


21


as well as


46


and


47


and in the area of the intermediate element


48


, i.e. of its intermediate element portions


49


and


50


, by abraded material of the intermediate element, which has the advantage that the values of the friction between the intermediate element portions


49


and


50


and the supporting limbs


20


and


21


are maintained and an increase of the friction values is avoided, which guarantees a persistently smooth drive of the second toothed cutter


24


without the necessity of lubrication at the location of the supporting limbs even after a long operating time.




The invention is not limited to the embodiment of a hair-cutting apparatus described above by way of example. The measures in accordance with the invention can be applied with advantage to a beard trimmer but also to a shaving apparatus having a toothed cutting device. The measures in accordance with the invention can also be applied to an apparatus having a toothed cutting device whose two toothed cutters have only one supporting limb each. Moreover, it is possible that each of the two toothed cutters has, for example, three supporting limbs, the supporting limbs of the two toothed cutters facing one another pairwise. In the toothed cutting device


7


of the apparatus


1


in the embodiment described herein by way of example the separate cutter support


8


is made of a synthetic resin; however, this is not necessarily so because adjacent its tooth row the stationary toothed cutter can be of such a construction that at the same time it serves as a cutter support. In the toothed cutting device


7


of the apparatus


1


in the embodiment described herein by way of example the entire stationary toothed cutter


13


is made of steel; this is not necessarily so because the stationary toothed cutter can be made of steel only in the area of its cutter tooth row and adjacent the steel cutter part can consist of a further cutter part of a preferably dimensionally stable and comparatively hard synthetic resin, which further part is fixedly connected to the steel cutter part, the synthetic-resin further cutter part of the stationary toothed cutter having at least one supporting limb for cooperation with an intermediate element portion of an intermediate element carried by the drivable toothed cutter. Likewise, the synthetic-resin further cutter part may then at the same time act as the cutter support. In a further variant of an apparatus in accordance with the invention or a toothed cutting device in accordance with the invention the intermediate element can also be carried by the stationary toothed cutter, as is known per se from the document DE 26 46 818 A1.



Claims
  • 1. An apparatus for cutting hairs, having a toothed cutting device which comprises a drive mechanism, a first toothed cutter with a first cutter-tooth row, which extends in a tooth row direction and comprises a plurality of cutter teeth, a second toothed cutter with a second cutter-tooth row, which also extends in the tooth row direction and comprises a plurality of cutter teeth, in which:said first toothed cutter is reciprocatingly drivable relative to said second toothed cutter in accordance with a given stroke H, by a reciprocating bridge driven by said drive mechanism of the apparatus, both toothed cutters lie against one another in the area of their cutter-tooth rows, both toothed cutters have at least one supporting limb each in their areas which, in directions transverse to the tooth row direction, are remote from the cutter tooth rows, which supporting limbs face one another pairwise and each have a given dimension in the tooth row direction, one of the two toothed cutters carries an intermediate element of a low-friction material, which intermediate element comprises at least one intermediate element portion interposed between said two facing supporting limbs, via which portion the at least one supporting limb of this one toothed cutter acts upon the at least one supporting limb of the other toothed cutter and has a given dimension in the tooth row direction, wherein the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a smaller dimension in the toothed cutter direction than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion.
  • 2. An apparatus as claimed in claim 1, wherein the intermediate element mainly consists of a polyamide in which silicon and polytetrafluoroethylene have been embedded.
  • 3. A toothed cutting device for an apparatus for cutting hairs, which toothed cutting device comprises a first toothed cutter with a first cutter-tooth row, which extends in a tooth row direction and comprises a plurality of cutter teeth, and a second toothed cutter with a second cutter-tooth row, which also extends in the tooth row direction and comprises a plurality of cutter teeth, in which:said first toothed cutter is reciprocatingly drivable relative to said second toothed cutter in accordance with a given stroke H, by a reciprocating bridge driven by said drive mechanism of the apparatus, both toothed cutters lie against one another in the area of their cutter-tooth rows, both toothed cutters have two supporting limbs each in their areas which, in directions transverse to the tooth row direction, are remote from the cutter tooth rows, which supporting limbs face one another pairwise and each are spaced apart in the tooth row direction, one of the two toothed cutters carries an intermediate element of a low-friction material, which intermediate element comprises at least one intermediate element portion interposed between said two facing supporting limbs, via which portion at least one supporting limb of this one toothed cutter acts upon at least one supporting limb of the other toothed cutter and has a given dimension in the tooth row direction, wherein the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a smaller dimension in the toothed cutter direction than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion.
  • 4. An apparatus for cutting hairs, having a toothed cutting device which comprises a drive mechanism, a first toothed cutter with a first cutter-tooth row, which extends in a tooth row direction and comprises a plurality of cutter teeth, a second toothed cutter with a second cutter-tooth row, which also extends in the tooth row direction and comprises a plurality of cutter teeth, in which:said first toothed cutter is reciprocatingly drivable relative to said second toothed cutter in accordance with a given stroke H, by a reciprocating bridge driven by said drive mechanism of the apparatus, both toothed cutters lie against one another in the area of their cutter-tooth rows, both toothed cutters have two supporting limbs each in their areas which, in directions transverse to the tooth row direction, are remote from the cutter tooth rows, which supporting limbs face one another pairwise and each are spaced apart in the tooth row direction, one of the two toothed cutters carries an intermediate element of a low-friction material, which intermediate element comprises at least one intermediate element portion interposed between said two facing supporting limbs, via which portion at least one supporting limb of this one toothed cutter acts upon at least one supporting limb of the other toothed cutter and has a given dimension in the tooth row direction, wherein the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a smaller dimension in the toothed cutter direction than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion.
  • 5. An apparatus as claimed in claim 4, wherein the intermediate element is substantially U-shaped and comprises two intermediate element limbs, which extend substantially perpendicularly to the tooth row direction, and an intermediate element base, which extends substantially parallel to the tooth row direction and which interconnects the two intermediate element limbs, and the free end portions of the two intermediate element limbs are each interposed as intermediate element portions between two respective supporting limbs.
  • 6. An apparatus as claimed in claim 5, wherein the two intermediate element limbs of the U-shaped intermediate element are each integrally connected to a substantially U-shaped holder, in such a manner that a passage is formed between each of the intermediate element limbs and the holder which is integrally connected to the respective limb, and each passage is engaged by a supporting limb of the toothed cutter carrying the intermediate element, in order to hold the intermediate element.
  • 7. A toothed cutting device for an apparatus for cutting hairs, which toothed cutting device comprises a drive mechanism, a first toothed cutter with a first cutter-tooth row, which extends in a tooth row direction and comprises a plurality of cutter teeth, and a second toothed cutter with a second cutter-tooth row, which also extends in the tooth row direction and comprises a plurality of cutter teeth, in which:said first toothed cutter is reciprocatingly drivable relative to said second toothed cutter in accordance with a given stroke H, by a reciprocating bridge driven by said drive mechanism of the apparatus, both toothed cutters lie against one another in the area of their cutter-tooth rows, both toothed cutters have at least one supporting limb each in their areas which, in directions transverse to the tooth row direction, are remote from the cutter tooth rows, which supporting limbs face one another pairwise and each has a given dimension in the tooth row direction, one of the two toothed cutters carries an intermediate element of a low-friction material, which intermediate element comprises at least one intermediate element portion interposed between said two facing supporting limbs, via which portion the at least one supporting limb of this one toothed cutter acts upon the at least one supporting limb of the other toothed cutter and has a given dimension in the tooth row direction, wherein the at least one intermediate element portion of the intermediate element carried by one of the two toothed cutters has a smaller dimension in the toothed cutter direction than the at least one supporting limb of the other one of the two toothed cutters, which last-mentioned supporting limb faces the at least one intermediate element portion said smaller dimension being smaller by an amount at least equal to the stroke H.
  • 8. A toothed cutting device as claimed in claim 7, wherein the intermediate element mainly consists of a polyamide in which silicon and polytetrafluoroethylene have been embedded.
Priority Claims (1)
Number Date Country Kind
97890076 Apr 1997 EP
US Referenced Citations (13)
Number Name Date Kind
1332553 Halterman Mar 1920
1682447 Van Osdel Aug 1928
1835613 Perlman Dec 1931
1997768 Dreverhoff Apr 1935
2029791 Pluchino Feb 1936
2704887 Andis Mar 1955
3052025 Ring Sep 1962
3729821 Voight et al. May 1973
4989324 Andis Feb 1991
5068966 Wahl et al. Dec 1991
5088200 Piwaron et al. Feb 1992
5170563 Van Der Grijn Dec 1992
5325590 Andis et al. Jul 1994
Foreign Referenced Citations (1)
Number Date Country
2646818A1 May 1977 DE