GB2118886A - Electric shaver - Google Patents

Abstract

An electric shaver of an oscillating type which includes a shaver head portion or upper casing 2 having a movable blade 35 and a screen blade 37. The upper casing 2 is arranged to be tilted with respect to a main casing 1 of the shaver. A trimmer unit 10 projects from the main casing 1 in a direction opposite to the tilting direction of the shaver head portion 2 for facilitating trimming of hair. A locking device 109 for a pushbutton 108 of a power on/off switch (105, Fig. 8) is provided to prevent accidental functioning of the power on/off switch (105, Fig. 8). <IMAGE>

Description

SPECIFICATION Electric shaver The present invention generally relates to a shaver and more particularly, to an electric shaver of an oscillating type, in which a shaver head portion or upper casing including an inner blade or movable blade and a stationary outer blade or screen blade, is arranged to be pivoted or tilted with respect to a shaver main casing.

Electric shavers of this type are convenient to use, since the angle of the shaving blades with respect to the skin may be adjusted by tilting the shaver head portion. Conventionally there has been proposed an electric shaver of this kind in which the shaver head portion is arranged to be held in an inclined position for stability during use.

In such an electric shaver a screen blade holder is detachably mounted on the shaver head portion to enable cut hair to be cleaned out and removed and to enable replacement of the screen blade. Lock means are provided to maintain the locked state of the screen blade holder.

In the conventional electric shavers of the above described type, the number of parts involved and the time required for assembly, are high. Electric shavers are also known which include a trimmer unit, although such trimmer units are not necessarily convenient for actual use, owing to the construction of the electric shaver.

According to this invention an electric shaver comprises a main casing, an upper casing including a movable shaving blade and a screen blade holder detachably attached to the upper casing, the upper casing being coupled to the main casing for pivotal movement between a first position in which it is aligned with the main casing and a second position in which it is inclined at a predetermined angle to the main casing, an oscillating member arranged to move as one unit with the movable shaving blade and located in the upper casing, an oscillation driving means and an oscillation generator which are located in the main casing, the oscillation driving means driving the oscillating member in both positions of the upper casing, means for positioning the upper casing at the first and second positions, and means for locking the screen blade holder on the upper casing.

A particular example of an electric shaver in accordance with this invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a perspective view from the front and one side; Figure 2 is a perspective view from the rear and other side; Figure 3 is a fragmentary side sectional elevation; Figure 4 is a fragmentary front sectional elevation, to an enlarged scale, of the upper front portion; Figure 5(a) is an exploded perspective view of a screen blade holder, an upper case, and engaging pieces; Figure 5(b) is an exploded perspective view of an oscillating member, an oscillating driving member, a trimmer unit, a mounting base and an electric motor; Figure 6 is a diagram showing the projection/retreat operating mechanism of the trimmer unit;; Figure 7(a) is a fragmentary side sectional elevation of an upper portion of the electric shaver in the operating state; Figure 7(b) is a fragmentary side sectional elevation showing the operating state of the trimmer unit; Figure 8 is a fragmentary side sectional elevation of a lock means for a pushbutton switch; and, Figure 9 is an exploded perspective view of a pushbutton, a sliding knob and the pushbutton switch.

Referring now to the drawings, there is shown, in Figs. 1 through 5(b), an electric shaver of a vibration type according to one preferred embodiment of the present invention, which generally includes a main casing 1 of a rectangular box-like configuration having a front wall 1 a, a rear wall 1 b, side walls 1 5 and a bottom wall, and an upper casing 2 (Figs. 5(a) and 5(b)) pivotally mounted on an upper portion of the main casing 1 for rotational movement between a first position P 1 directed straight upwards in a direction parallel to an axis of the main casing 1 and indicated by solid lines, and a second position P2 tilted at a predetermined angle with respect to the axis of the main casing 1 towards the front wall 1 a of said main casing 1 as shown in chain lines in Fig. 2.

More specifically, as shown in Figs. 3, 4, 5(a) and 5(b), the main casing 1 further includes a mounting base 3 secured at its upper portion, a motor 4 mounted at the lower portion of the mounting base 3, an eccentric cam 6 fixed to a shaft 5 of the motor 4 extending upwardly through the mounting base 3, and an eccentric pin 7 provided on the eccentric cam 6 so as to project upwardly therefrom. Meanwhile, in a wall 8 extending upwardly from the upper portion of the rear wall 1 b of the main casing 1 at the back of the mounting base 3, there is formed a cut out portion 9, into which a trimmer unit 10 is fitted.

The trimmer unit 10 includes a blade holder 11, and a stationary blade 1 2 and a movable blade 1 3 which are supported by the blade holder 11, and support pins 14 extending laterally outwardly from opposite ends of the blade holder 11 (Fig.

5(b)), and thus, the trimmer unit 10 is pivotally supported within the cut out portion 9 through said support pins 1 4 for movement between a retracted position parallel to and flush with the surface of the wall 8 of the main casing 1 and a projected position directed in a direction at right angles with respect to the surface of said wall 8. In an outer surface of one side wall 1 5 of the main casing 1, an operating knob 1 6 is slidably fitted for vertical movement along the axis of the main casing 1 for selective projection or retraction of said trimmer unit 10 as described earlier.More specifically, as shown in Fig. 6, a pin 1 9 projecting from the operating knob 1 6 is engaged with a bifurcated portion 18a formed at one end of a rocking plate 1 8 pivotally supported about a shaft 17 within the side wall 15 of the main casing 1, and a pin 20 provided at the other end of the rocking plate 1 8 is engaged with a groove 22 formed at a lower end of an operating lever 21 supported for vertical movement within the main casing 1, while a hook 21 a provided at an upper end of the operating lever 21 is engaged with an L-shaped receiving portion 23 formed at one end of the blade holder 11 of the trimmer unit 10 in an attitude for the retraction.

By the above arrangement, upon upward sliding movement of the operating knob 1 6, the operating lever 21 is pulled down through the rocking plate 18, and thus, the trimmer unit 10 is pivoted upwardly about the pins 14 through approximately 90 as shown by chain lines in Figs.

3 and 6 so as to be projeceted rearwardly from the outer surface of the wall 8 of the main casing 1.

Conversely, if the operating knob 1 6 is slid downwardly, the operating lever 21 is pushed up through the rocking plate 18, and the trimmer unit 10 is pivoted downwardly about the support pins 14 so as to be brought into the retracted position shown by solid lines in Figs. 3 and 6.

Subsequently, means for positioning the upper casing 2 at the first position P 1 and the second position P2, and means for locking the screen blade holder 38 on said upper casing 2 will be described hereinbelow.

The upper casing 2 has boss portions 25 (Figs.

4 and 5(a)) formed in its opposite side walls 24, and the boss portions 25 are fitted onto corresponding boss portions 26 formed on upper inner portions of the opposite side walls 1 5 of the main casing 1, so that the upper casing 2 may be rotated back and forth about the boss portions 26.

In this embodiment, the upper casing 2 is arranged to be positionally changed over in two stages, between the first or neutral position P1 where its axis is located on the axis Y-Y of the main casing 1 (Figs. 2 and 3) and the second or tilted position P2 where its axis is inclined with respect to the axis Y-Y of the main casing 1 at an angle of about 1 50 towards the front wall 1 a of the main casing 1, and the positioning means for the above purpose is provided between the upper casing 2 and the mounting base 3 described earlier.

More specifically, the upper casing 2 has rectangular openings 27 formed in the corresponding side walls 24 thereof (Fig. 5(a)), while engaging pieces 28 each having an outer end 28b of a triangular cross section and an inner end 28a provided, for example, with a detent ball B, are respectively fitted into said rectangular openings 27 of the upper casing 2 at the outer end 28b thereof. Each of the engaging pieces 28 is further formed with resilient retaining pieces I on corner portions thereof at its inner end 28a for engagement with the peripheral inner edge of the rectangular opening 27 of the upper casing 2.The detent balls B at the inner ends 28a of the respective engaging pieces 28 are adapted to contact under pressure, corresponding outer faces of resilient plates 29 extending upwardly from opposite side portions of the mounting base 3 (Fig. 5(b)), while each of the resilient plates 29 is formed with rotation restricting openings or recesses 30 and 31 in two positions on an imaginary circle (not shown) drawn with respect to the boss portion 26 as a center.

Meanwhile, the screen blade holder 38 holding the screen blade 37 for sliding contact with the movable blade 35 is detachably mounted over the upper casing 2, and has side walls 39 confronting the outer faces of the corresponding side walls 24 of the upper casing 2, and is provided with retaining recesses 40 formed in the inner faces of the respective side walls 39 thereof for releasably receiving therein the outer ends 28b of the engaging pieces 28 described earlier.

In the above arrangement, the upper casing 2 including the screen blade 37 and movable blade 35, may be pivoted in the forward and backward directions as described earlier. In the state where the upper casing 2 is in the first or neutral position P 1 located on the axis Y-Y of the main casing 1 (Figs. 2 and 3), the detent balls B at the inner ends 28a of the engaging pieces 28 engage the rotation restricting openings 31 of the resilient plates 29 at the side of the main casing 1 so as to retain the upper casing 2 at the first neutral position P 1.For tilting the upper casing 2 forwardly from the first neutral position P 1 to the second tilted position P2, the upper casing 2 is rotated forwardly about the boss portions 26, and following the above rotation, the detent balls B at the inner ends 28a of the engaging pieces 28 are disengaged from the rotation restricting openings 31 for subsequent engagement with the other rotation restricting openings 30 so as to retain the upper casing 2 in the second tilted position P2.

On the other hand, the screen blade holder 38 is retained in the state where it is mounted on the upper casing 2 by the engagement of the retaining recesses 40 thereof with the outer ends 28b of the engaging pieces 28 urged outwardly by the resiliency of the resilient plates 29. For detaching the screen blade holder 38 from the upper casing 2, the screen blade holder 38 is pulled upwardly for sliding the retaining recesses 40 thereof over the outer ends 28b of the engaging pieces 28 for once displacing said engaging pieces 28 inwardly.

Meanwhile, for application of the screen blade holder 38, said holder 38 is fitted over the upper casing 2 from above so as to once depress the outer ends 28b of the engaging pieces 28 inwardly at the lower ends of the side walls 39 of the holder 38, and upon coincidence of the retaining recesses 40 with the outer ends 28b of the engaging pieces 28, said engaging pieces 28 are pushed out by the resiliency of the resilient plates 29 for automatic engagement of the outer ends 28b thereof with the retaining recesses 40.

Inside the upper casing 2, there is provided in a suspended manner, a vibrating member 32, for example, of a plastic material, subjected to oscillation through elastic deformation in lateral directions, while a pin 33 projecting upwardly from the upper surface of the vibrating member 32 in a forwardly inclined state, is arranged to extend through a central opening 34 of the upper casing 2, with a holder 36 for the movable blade 35 being connected to said pin 33.

In the under surface of the vibrating member 32, a concave groove 41 having an arcuate cross section is formed in the back and forth direction of the main casing 1, and in said concave groove 41, a vibration driving member 42, for example, of a plastic material having a convex arcuate cross section is slidably engaged. The vibration driving member 42 as described above has an elongated groove 43 formed in its under surface in the back and forth direction of the main casing 1, with the eccentric pin 7 described earlier being received in said groove 43. The vibration driving member 42 is also provided with a V-shaped block 44 integrally formed at its rear face so as to provide an engaging portion 45 at a V-shaped groove of said block 44.An engageable portion 46 in a lug shape extending from the movable blade 1 3 of the trimming unit 10 is arranged to engage the engaging portion 45 of the block 44 when the trimmer unit 10 is in the projected state, and to disengage from said engaging portion 45 when the trimmer unit 10 is in the retracted state.

By the above construction, upon rotation of the eccentric cam 6 through driving by the motor 4, the vibration driving member 42 engaged with the eccentric pin 7 of the cam'6 is subjected to reciprocating vibration in the lateral direction for the vibration of the vibrating member 3 in that direction, by which vibration, the movable blade 35 is also subjected to the lateral reciprocating vibration for sliding contact with the inner face of the screen blade 37.

In Fig. 3 and 7(a) both showing the states of the electric shaver ready for shaving, the trimmer unit 10 is kept retracted into the wall 8 of the main casing 1. Fig. 3 shows the state where the upper casing 2 is in the first neutral position P1 without being tilted forwardly, while Fig. 7(b) illustrates the state where said upper casing 2 is inclined forwardly into the second tilted position P2, and either of the above states may be selected as desired according to portions to be shaved or convenience for users.It is to be noted here that, in the embodiment described so far, although the upper casing 2 is arranged to be inclined forwardly towards the second position P2 through the angle of about 1 50 with respect to the main casing 1, such inclination angle may be altered and set as desired according to the requirements so far as the vibration driving member 42 is held in engagement with the concave groove 41 of the vibrating member 32 at all times.

For effecting the trimming, the upper casing 2 is inclined forwardly into the second tilted position P2 as shown in Fig. 7(b), while the trimmer unit 10 is caused to project out of the main casing 1 in a direction opposite to the inclination of the upper casing 2, and by the above projection, the engageable portion 46 of the movable blade 13 engages the engaging portion 45 of the vibration driving member 42 for driving of the movable blade 1 3 of the trimmer unit 10.It is to be noted that, when the engaging portion 45 is formed into the configuration of the V-shaped groove as in the embodiment described so far, the engageable portion 46 may be kept engaged with the corresponding engaging portion 45, even when the vibration driving member 42 is positionally deviated in the lateral direction from the position of the engageable portion 46 of the trimmer unit 10, and that the motor 4 as the driving device may, of course, be replaced, for example, by an electro-magnet or the like, and also, that the tilting of the upper casing 2 is not limited to the two stages as described in the foregoing, but may be arranged to be effected through a plurality of stages.

Subsequently, means for locking a power on/off switch for power supply to the electric shaver will be described hereinbelow.

As shown in Figs.1,8 and 9, in a rectangular opening 102 formed in the front wall 1 a of the main casing 1, a switch panel 103 is fitted, while a printed circuit board 104 is disposed in the main casing 1 behind the opening 102, with the power on/off switch 105, a battery 106, and other circuit components being connected to said printed circuit board 104.

The switch panel 103 is formed with a rectangular opening 107, in which a square type pushbutton 108 and a sliding type knob 109 arranged side by side in the vertical direction are fitted. The pushbutton 108 is coupled to the switch 105 through insertion of a projection 110 provided on the inner face thereof into a sleeve 111 protruding forwardly from the switch 105 for free projection or retraction thereof with respect to the switch 105, and said pushbutton switch 105 as referred to above is of a type which is actuated upon depression of the pushbutton 108 into the main casing 1, but is not restored back to the original position even when it is released from the depression, and is restored to the original position only when depressed once more.

The sliding type knob 109 is fitted into the opening 107 of the switch panel 103 so as to be vertically slidable as desired in a direction intersecting at right angles with the depressing direction of the pushbutton 1 09. A locking piece 112 extends upwardly from the inner face of the knob 109, so that, through vertical operation of the knob 109, the upper edge of the locking piece 112 is engaged with or disengaged from a recess 11 3 provided in the under face of the sleeve 111 which is a connecting portion between the pushbutton 108 in a closed state and the switch 105.

By the above arrangement, upon downward sliding operation of the sliding knob 109, the locking piece 11 2 which moves as one unit with the knob 109 is disengaged from the recess 11 3 at the connecting portion of the pushbutton 108 and the switch 105, so as to allow the pushbutton 108 to be depressed inwardly. By the above depression, the switch 105 is actuated to turn on the power supply for the electric shaver. Upon depression of the pushbutton 108 again, the pushbutton 108 is restored back to the original protruding position so as to cut off the power supply.

In the above cut-off state, when the sliding knob 109 is slid upwardly, the locking piece 11 2 thereof engages the recess 11 3 of the above connecting portion to lock the pushbutton 108 for making it impossible to actuate the switch 105 by the depression thereof. It is to be noted here that, in the above case, when a stepped portion 114 formed at an upper edge of the sliding knob 109 is arranged to enter the inner side of a lower edge 1 08a of the pushbutton 108 so as to receive the inner face of the lower edge 1 08a as shown, the obstruction against depression of the pushbutton 108 may be made more positive.Moreover, in the embodiment as illustrated, for further preventing the sliding knob 109 from being inadvertently lowered, two leg pieces 11 5 are provided to depend from said knob 109, such that said leg pieces 114 contact corresponding projections 11 6 formed at the side of the main casing 1 as the knob 109 is slid upwardly, and go over said projections 11 6 through elastic deformation so as to be stopped on said projections 116 when the knob 109 has arrived at an upper limit (i.e. locking position) for its upward sliding movement.

It should be noted here that, in the above arrangement, friction in the sliding movement of the knob 109 with respect to the opening 107 of the switch panel 103 may further be increased, or degree of entry of the locking piece 112 into the recess 113 may also be increased.

It should also be noted that, in the embodiment of Figs. 8 and 9, although the locking piece 112 is arranged to be engaged with or disengaged from the sleeve 111 at the connecting portion of the pushbutton 108 and the switch 105, the arrangement may be modified in such a manner that such locking piece 112 is engaged or disengaged with respect to qther portions at the connecting portion of the pushbutton 108 and the switch 105, for example, with respect to the projection 110 projecting from the pushbutton 108.

In the arrangement of Figs. 8 and 9, since the locking piece 112 of the knob 109 which is slid in the direction intersecting at right angles with the depressing direction of the pushbutton 108, is adapted to engage the connecting portion of the pushbutton 108 and the switch 105 to be actuated by the depression of said pushbutton, erroneous functioning of the pushbutton switch during carrying about of the shaver may be positively prevented.

As is clear from the foregoing description, according to the present invention, the engaging pieces 28 are fitted into the openings 27 formed in the tiltable upper casing 2, while the inner and outer ends 28a and 28b of the engaging pieces 28 are respectively, releasably fitted into the rotation restricting openings 30 or 31 formed in the resilient plates 29, and also, into the retaining recesses 40 of the screen blade holder 48, so that the inclination angle is maintained for stability of the upper casing 2, while positive mounting and locking of the screen blade holder may be achieved.Accordingly, since the positioning means, i.e. inclination maintaining means for the upper casing 2 and the mounting and locking means for the screen blade holder 38 can be constituted only by two kinds of members, i.e. the engaging pieces 28 and the resilient plates 29 which may be simultaneously utilized for the both means, not only the assembly of the shaver is facilitated, but such engaging pieces 28 and the resilient plates 29 may be incorporated even into small spaces. Moreover, by the resilient plates 29 alone, the engaged state between the inner and outer ends 28a and 28b of the engaging pieces 28 and the rotational restriction openings 30 and 31, and also the retaining recesses 40, may be positively maintained at all times.Furthermore, for cleaning cut hair adhering to or accumulated on the movable blade 35 and the upper casing 2, the screen blade holder 38 contacting the outer ends 28b of the engaging pieces 28 is detached from the upper casing 2, and thus, the engaging pieces 28 are fully pushed outwardly by the resilient plates 29, with a consequent reduction of contact pressure of the resilient plates 29 with respect to the inner ends 28a of the engaging pieces 28.

Therefore, the upper casing 2 which is rather difficult to hold due to detachment of the screen blade holder 38 may be tilted by a slight operating force for facilitation of the cleaning of cut hair.

Moreover, according to the present invention, since the upper casing 2 is arranged to be tiltable in the direction intersecting at right angles with the vibrating direction of the movable blade 35, and opposite to the projecting direction of the trimmer unit 10 with respect to the main casing 1, not only the angle of the movable blade 35 is adjusted as desired during shaving for improved handling convenience, but the trimming may be effected in a very efficient manner, since the upper casing 2 which would otherwise be a hindrance to trimming, may be tilted from the trimmer unit 10 as far as possible. Meanwhile, since the vibration driving member 42 having the engaging portion 45 arranged to be engaged with or disengaged from the engageable portion 46 of the trimmer unit 10 is adapted to be located at the side of the main casing 1 irrespective of the tilting of the upper casing 2, the engaging position between the vibration driving member 42 and the trimmer unit 10 is not altered even when the upper casing 2 is tilted, and thus, the trimming blades may be driven positively at all times.

Claims (7)

1. An electric shaver comprising a main casing, an upper casing including a movable shaving blade and a screen blade holder detachably attached to the upper casing, the upper casing being coupled to the main casing for pivotal movement between a first position in which it is aligned with the main casing and a second position in which it is inclined at a predetermined angle to the main casing, an oscillating member arranged to move as one unit with the movable shaving blade and located in the upper casing, an oscillation driving means and an oscillation generator which are located in the main casing, the oscillation driving means driving the oscillating member in both positions of the upper casing, means for positioning the upper casing at the first and second positions, and means for locking the screen blade holder on the upper casing.

2. An electric shaver according to claim 1, wherein the upper casing positioning means and the screen blade holder locking means are formed by common means including engaging pieces each having inner ends and outer ends, the engaging pieces fitting into openings formed in side walls of the upper casing at locations away from the pivot axis of the upper casing and movable through the openings, the outer ends of the engaging pieces extending outwards from the openings and engaging retaining recesses formed in side walls of the screen blade holder to locate the screen blade holder in position, the inner ends of the engaging pieces projecting inwards from the openings and being slidable over outer surfaces of resilient plates forming part of the main casing, the resilient plates including recesses in which the inner ends of the engaging pieces engage to restrict the pivoting of the upper casing at the first and second positions.

3. An electric shaver according to claim 1 or 2, further including a trimmer unit projectable from or retractable into the main casing upon its pivotal movement, the trimmer unit projecting in a direction opposite to the inclination of the upper casing in its second position, the oscillating driving member being provided with an engaging portion which is engageable with or disengageable from a corresponding portion provided on a movable blade of the trimmer unit to transfer the oscillation to the movable blade of the trimmer unit when it projects from the main casing.

4. An electric shaver according to claim 1, 2 or 3, further including a pushbutton mounted in part of an outer surface of the main casing, and a power on/off switch provided in the main casing and associated with the pushbutton to be actuated by depression of the pushbutton, a sliding knob provided on the outer surface of the main casing to be slidable in a plane normal to the direction of movement of the pushbutton, the sliding knob being provided with a locking piece which moves with the sliding knob for selectively engaging a connecting portion between the pushbutton and the power on/off switch.

5. An electric shaver constructed substantially as described with reference to the accompanying drawings.

6. An electric shaver which comprises a main casing, an upper casing including a shaving movable blade and a screen blade holder detachably attached onto said upper casing, said upper casing being coupled to said main casing for pivotal movement between a first position directed in parallel to an axis of the main casing and a second position inclined at a predetermined angle with respect to the axis of the main casing, a vibrating member arranged to be vibrated in one unit with the shaving movable blade and provided in said upper casing, a vibration driving means and a driving means for the vibration driving means which are provided in said main casing, means for positioning the upper casing at said first and second positions, and means for locking said screen blade holder on said upper casing, a trimmer unit arranged to be projectable from or retractable into the main casing through pivotal movement of said trimmer unit so as to be projected in a direction opposite to the direction of the pivotal movement of said upper casing towards said second position intersecting at right angles with the vibrating direction of said shaving movable blade, said vibrating member being engaged with said vibrating driving member so as to be slidable in the direction of the pivotal movement of said upper casing for tilting towards said second position, said vibration driving member being provided with an engaging portion which is engageable with or disengageable from an engageable portion provided on a movable blade of the trimmer unit following the pivotal movement of said trimmer unit for the projection and retraction, a pushbutton mounted in part of an outer surface of the main casing, and a power on/off switch provided in said main casing.

7. An electric shaver which comprises a main casing, an upper casing including a shaving movable blade and a screen blade holder detachably attached onto said upper casing, said upper casing being coupled to said main casing for pivotal movement between a first position directed in parallel to an axis of the main casing and a second position inclined at a predetermined angle with respect to the axis of the main casing, a vibrating member arranged to be vibrated in one unit with the shaving movable blade and provided in said upper casing, a vibration driving means and a driving means for the vibration driving means which are provided in said main casing, means for positioning the upper casing at said first and second positions, and means for locking said screen blade holder on said upper casing.