JPH08257262A - Rotary electric razor - Google Patents

Abstract

PURPOSE: To provide a rotary electric razor improved in shaving quality by enhancing the accuracy when an inner blade is in slidable contact with the inner peripheral face of an outer blade. CONSTITUTION: An inner blade stand 10 to which an inner blade 17 is fitted is arranged in a housing chamber (recessed housing part) 4, whose one side is opened an outer blade 30 provided with a central frame 34 having many mustache introducing holes in its opening and formed with a centering hole in its central part is fitted, and an output shaft 7 of a motor 3 provided in a main body 1 is passed through a through hole (the centering hole) 13 of the inner blade stand 10 to fit its top end part to the centering hole 35, thereby the inner blade stand 10 can be rotted through the output shaft 7 with the centering hole 35 as a rotational center.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary electric shaver, and more particularly to a rotary electric shaver which improves precision of sliding contact of an inner blade with an inner peripheral surface of the outer blade to improve sharpness.

[0002]

2. Description of the Related Art A conventional well-known rotary electric shaver is provided with a storage chamber having an opening at one end thereof, an inner blade base having an inner blade attached therein, and the opening of the storage chamber. The beard is closed and attached with an outer blade having a large number of beard introducing holes, and is rotated while the inner blade is pressed against the inner peripheral surface of the outer blade together with the inner blade base by a motor provided in the main body. The beard introduced from the introduction hole is shaved by shaving. Then, in this type of rotary electric shaver, the inner peripheral surface of the outer blade is formed into a spherical shape, and the whisker is sheared by rotating the inner peripheral surface of the spherical blade while pressing the blade body of the inner blade, that is, the cutting edge. It is configured so that good shaving cannot be performed unless the blade body of the inner blade is accurately pressed, that is, slidably contacted with the spherical inner peripheral surface during rotation.

Therefore, in order to bring the blade tip of the inner blade into sliding contact with the inner peripheral surface of the outer blade with high precision, the center of the outer blade and the center of rotation of the inner blade base to which the inner blade is attached are made to coincide with each other. There is. A conventional device thus configured will be described with reference to FIG.

In the figure, reference numeral 100 is a main body of a rotary electric shaver, the main body 100 includes a main body case 102, a motor 103 mounted in the main body case 102,
It is composed of a storage battery (not shown) that supplies electric power to the motor 103, a charging device that charges the storage battery, and the like. Then, one end side (see FIG.
A storage chamber 104 that is open to the upper side) and is surrounded by a cylindrical wall, that is, an annular wall 104a is formed, and a through hole 105 is formed in a bottom wall 104b of the storage chamber 104. A male screw 104c is formed on the outer peripheral portion of the annular wall 104a. A mounting member 106 is formed on the back surface side of the bottom wall 105 of the main body case 102. The motor 103 is mounted in the main body case 102 by the mounting member 106. Further, when the motor 103 is attached to the main body case 102, the output shaft 107 of the motor 103 penetrates a through hole 105 formed in the bottom wall of the storage chamber 104 and projects into the storage chamber 104. Then, this output shaft 107
The fitting shaft 108 is attached to the so as to be prevented from rotating in the circumferential direction. The fitting shaft 108 has a notch 108a for preventing rotation and a centering hole 108b formed in the upper portion in the drawing, and a shaft hole 108c into which the output shaft 107 is fitted formed in the lower portion. There is.

The inner shaft 11 is attached to the fitting shaft 108.
0 is detachably attached, and this inner blade base 110
An engaging projection 112 is formed in the center of the shaft, and a shaft hole 111 into which the fitting shaft 108 is fitted is formed.
The center of the shaft hole 111 is the fitting shaft 108.
Through-hole 11 aligned with the center of the centering hole 108b formed in
3 are formed, and inner blade mounting holes 114 are formed radially around the through hole 113. An inner blade 117 having a blade 117a formed at the tip of the inner blade mounting hole 114 and an engaging hole 117b provided at the lower portion is provided at one end of the inner blade 117a. Stand 1
By inserting the other end side of the leaf spring 119 attached by the fixing tool 118 into the lower surface of the device 10, the leaf spring 119 is always urged upward and attached.

Then, the annular wall 104 of the storage chamber 104.
An outer blade case 120 to be attached to the outer periphery of a is attached by screwing an internal thread 121 formed on the inner peripheral surface into a male screw 104b formed on the outer periphery of the annular wall 104a. An outer blade 130 is attached by closing the opening of the storage chamber 104. This outer blade 1
Reference numeral 30 denotes a blade plate 132 in which a large number of beard introducing holes (not shown) are formed on a thin metal plate by etching.
The outer peripheral frame 133 is made of synthetic resin and is attached to the outer peripheral edge of the blade 2. The outer frame 133 is made of synthetic resin, and the central frame 134 is also made of synthetic resin and is attached to the central portion of the blade plate 132.

Then, the centering frame 1 is fitted in the centering hole 108b of the fitting shaft 108 by penetrating the through hole 113 formed in the inner cutter base 110 at the center of the center frame 134.
35 is attached by integral molding.

Then, as shown in the figure, the inner blade 1 is attached to the fitting shaft 108 attached to the output shaft 107 of the motor 103.
After assembling the inner blade stand 110 to which 17 is attached by fitting its shaft hole 111, and then attaching the outer blade case 120 to which the outer blade 130 is attached to the main body case 102, the electric razor is assembled as a use state. To be When assembled in this way, the centering shaft 135 provided on the central frame 134 of the outer blade 130 fits into the centering hole 108b of the fitting shaft 108, and the inner blade base 110
The center of rotation of the outer cutter 130 and the center of rotation of the outer cutter 130 are
And the blade body 117a of the inner blade 117 is matched by 35.
Is accurately slidably in contact with the outer blade, that is, the inner peripheral surface of the blade plate 132.

[0009]

As described above, in the conventional one, the center of the outer cutter 130 and the center of rotation of the inner cutter base 110 are made to coincide with each other by the centering shaft 135 provided on the central frame 134 of the outer cutter 130. Therefore, since the centering shaft 135 must be used as a separate component, there is a problem that the number of parts increases, and the centering shaft 1
Since 35 must be attached to the central frame by integral molding or the like, there is a problem that productivity is deteriorated because the number of assembling steps increases. Also, since the fitting shaft 108 is made of synthetic resin, the output shaft 107 of the motor 103 is
It is easy to cause the discrepancy between the shaft center of and the shaft center of the fitting hole 108c of the fitting shaft 108.
0 means that the center of rotation deviates from the original center of rotation, that is, it rotates in an eccentric state, so that the spherical inner peripheral surface of the blade plate 132 and the blade body 117a of the inner blade 117 can be brought into sliding contact with high precision. There is a problem that it is no longer possible to perform good shaving.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. The invention according to claim 1 has a storage recess formed in a circular recess having one end open, and a large number of whiskers introducing holes. An outer blade provided with a central frame in which a centering hole is formed in the central portion of the blade plate in which the outer peripheral frame is provided in the outer peripheral portion and the opening of the storage recess is closed and attached, and while being provided in the main body A motor having an output shaft protruding from the bottom of the storage recess and having its tip fitted into the centering hole; and an engaging portion provided on the output shaft of the motor for transmitting rotational force,
An engaged portion that engages with the engaging portion is formed on the bottom side of the storage recess, and a centering hole through which the output shaft is inserted is formed on the outer blade side, and a plurality of inner portions are formed around the centering hole. An inner blade base having a blade mounting hole, and an inner blade slidably provided in the inner blade mounting hole and having a blade body on one end side located on the outer blade side and an engaging portion on the other end side. And a rotary electric razor having one end attached to the inner blade base and the other end engaged with the engaging portion to bias the inner blade toward the outer blade,
Further, the invention according to claim 2 is such that an outer periphery of a storage concave portion formed in a circular concave shape having one end opened and a central frame in which a centering hole is formed in a central portion of a blade plate in which a large number of whisker introducing holes are formed. An outer blade provided with an outer peripheral frame on the housing to close and close the opening of the storage recess, and an output provided in the main body and protruding from the bottom of the storage recess to fit its tip into the centering hole A motor having a shaft, a fitting shaft having an engaging portion that is inserted into the output shaft of the motor so as to prevent rotation, and engages with the engaging portion on the bottom side of the storage recess. A fitting hole having an engaged portion into which the fitting shaft is inserted and a centering hole communicating with the fitting hole and through which the output shaft is inserted, are formed on the outer blade side, and An inner blade base having a plurality of inner blade mounting holes formed around the hole, and the inner blade mounting holes An inner blade that is slidably provided and has a blade body on one end side that is located on the outer blade side and an engaging portion on the other end side; and one end that is attached to the inner blade base and the other end that engages A clearance between the fitting hole formed in the inner blade base and the fitting shaft fitted in the fitting hole, which is made of an elastic body that engages with the inner blade and biases the inner blade toward the outer blade. Is a rotary electric shaver in which a large clearance is formed between the centering hole and the output shaft inserted into the centering hole.

[0011]

According to the first aspect of the present invention, the center frame provided in the central portion of the outer blade is formed with the centering hole, and the inner blade base is provided with the engaged portion and the centering hole. The engaging part attached to the output shaft of the motor is engaged with the shaft, the output shaft of the motor is inserted through the centering hole, and the tip end is fitted into the centering hole. Since the center of rotation of the blade base and the center of the outer blade are aligned, a centering shaft is not required, which reduces the number of parts and the number of assembly steps, and also the center of rotation of the inner blade and the center of the outer blade. It is possible to make an accurate match.

According to a second aspect of the present invention, a centering hole is formed in a central frame provided in a central portion of the outer blade, and a fitting hole and a centering hole having an engaged portion on the inner blade base are formed. And a fitting shaft having an engaging portion which is attached to the output shaft of the motor is fitted into the fitting hole, and the output shaft of the motor is inserted into the centering hole, and the tip end thereof is fitted into the centering hole. Since the center of rotation of the inner blade and the center of the outer blade are made to coincide with each other by the output shaft of the motor, the centering shaft is not required and the number of parts and the number of assembly steps can be reduced. Since the clearance between the fitting hole of the blade base and the fitting shaft fitted in this fitting hole is made larger than the clearance between the centering hole and the output shaft inserted in this centering hole, the outer diameter of the fitting shaft Even if there is a discrepancy between the shaft center of the blade and the shaft center of the fitting hole, the center of rotation of the inner blade will be output by the motor. Can be positioned accurately, and therefore the center of rotation of the inner cutter base and the center of the outer cutter can be aligned more accurately, and as a result, the blade body of the inner cutter and the inner peripheral surface of the outer cutter can be brought into sliding contact with high precision. Good shaving is possible.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment of the present invention will be described with reference to FIGS. In the figure, reference numeral 1 is a main body of a rotary electric shaver, the main body 1 is a main body case 2, a motor 3 mounted in the main body case 2, and a motor 3
A storage battery (not shown) for supplying electric power to the storage battery, a charging device for charging the storage battery, and the like. A storage chamber 4 is formed in the main body case 2 as a storage recess which is open at one end side (upper side in FIG. 1) and is surrounded by a cylindrical wall, that is, an annular wall 4a, and a bottom wall 4b of the storage chamber 4 is formed. Has a through hole 5. A male screw 4c is formed on the outer peripheral portion of the annular wall 4a. On the back surface side of the bottom wall 4b of the body case 2, an annular mounting member 6 having a locking projection 6a at its tip is formed with its central axis aligned with the axial center of the through hole 5. ing. The motor 3 is mounted in the main body case 2 by the mounting member 6, and the motor 3 is mounted in this mounted state.
The bottom portion 3a of the above is locked by the locking projection 6a and is prevented from coming off. Further, when the motor 3 is attached to the main body case 2, the output shaft 7 of the motor 3 penetrates the through hole 5 formed in the bottom wall of the storage chamber 4 and projects into the storage chamber 4. A fitting shaft 8 is attached to the output shaft 7 so as not to rotate in the circumferential direction. A through hole 8a is formed at the center of the fitting shaft 8 to prevent the output shaft 7 from rotating in the circumferential direction and to be inserted therethrough, and a notch 8b serving as an engaging portion for preventing rotation is formed in the upper portion. . As a means for preventing the output shaft 7 and the through hole 8a of the fitting shaft 8 from rotating, as is well known in the art, the cross section of the output shaft 7 is formed in a D shape and the shape of the through hole 8a is described above. It may be formed in a D-shape like the cross section of the output shaft 7.

The motor 3 is attached to the main body case 2 after the fitting shaft 8 is attached to the output shaft 7 and then the motor 3 is directed toward the inside of the attachment member 6 from the direction of the arrow as shown in FIG. This is done by inserting and engaging the bottom portion 3a of the motor 3 with the locking protrusion 6a.

Next, the inner blade base 10 which is detachably attached to the fitting shaft 8 will be described. This inner blade stand 10
As shown in FIG. 7, a fitting hole 11 into which the fitting shaft 8 is fitted is formed in the central portion, and a notch 8b for preventing rotation of the fitting shaft 8 is provided at an upper portion of the fitting hole 11. Engagement projections 12 are formed as mating engaged parts. This engaging projection 12
By engaging the notch 8b with the notch 8b, the rotational force of the output shaft 7 is transmitted to the inner blade base 10 when the motor 3 is driven. In addition, the inner blade base 10 communicates with a fitting hole 11 and the fitting hole 11 and the output shaft 7 of the motor 3.
A through hole 13 is formed as a centering hole that coincides with the axis of. Further, a plurality of (three in the embodiment) inner blade mounting holes 14 are formed in the inner blade base 10 in a radial pattern centered on the through hole 13 and in parallel with the axis of the fitting hole 11. ing. Furthermore, a circular concave portion 1 for positioning a central frame 34 of an outer blade 30, which will be described later, in the central portion of the inner blade base 10.
5 is formed.

The inner blade 17 mounted in the inner blade mounting hole 14 formed in the inner blade base 10 has a blade body 17a formed at the upper end in the figure and a rectangular engaging portion at the lower portion. An engagement hole 17b is provided. The inner blade 17 has a lower portion penetrating the mounting hole 14 and inserted, and then one end of the inner blade 17 is inserted into the engaging hole 17b.
In the figure, by inserting the other end of the leaf spring 19 as an elastic body, which is attached to the lower surface by a fixture 18, the inner blade 17 is constantly urged upward in the figure and the inside of the attachment hole 14 is inserted. It is attached to the inner blade base 10 so as to be vertically movable.

Next, the outer blade case 20 attached to the outer periphery of the annular wall 4a of the storage chamber 4 will be described. The outer blade case 20 is formed in a cylindrical shape by a cylindrical wall, and an inner thread 21 is formed on the inner peripheral surface of the outer blade case 20 to be screwed with the male thread 4c formed on the outer circumference of the annular wall 4a. In the figure, an annular locking edge 22 having a diameter smaller than the diameter of the inner circumference of the outer blade case 20 is formed on the upper edge, and the inner peripheral surface is spaced from the locking edge 22 by a predetermined distance. A plurality of locking protrusions 23 are formed. Then, the locking edge 22, the locking projection 23, the inner peripheral surface 24 of the outer blade case 20.
A fitting recess 25 having a U-shaped cross section is formed by and.

The space surrounded by the inner peripheral surface located above the cylindrical wall of the outer blade case 20, that is, above the annular wall 4a of the storage chamber 4, constitutes the inner blade storage chamber together with the storage chamber 4. It is what

Next, the outer blade 30 detachably mounted in the outer blade case 20 will be described. As shown in FIGS. 4 to 6, the outer blade 30 has a blade plate 32 in which a large number of beard introducing holes 31 are formed by etching a thin metal plate, and a hole 32 a formed in the outer peripheral edge of the blade plate 32. An outer peripheral frame 33 made of a substantially ring-shaped synthetic resin, which is attached by heating and melting the tip of the inserted mounting boss 33e to increase its diameter, and inserts it into the mounting hole 32b formed in the central portion of the blade plate 32. A central frame 34 also made of synthetic resin is attached by heating and melting the tip of the attached boss 34a to increase its diameter.

On the outer periphery of the outer peripheral frame 33, an annular wall 33a axially slidable along the inner peripheral surface 22a of the locking edge 22 of the outer blade case 20 and a step portion 33d from the annular wall 33a. Is formed to have a diameter larger than that of the annular wall 33a, and the inner peripheral surface 24 is formed in the fitting recess 25 of the outer blade case 20.
A guide wall 33b that is slidable in the axial direction, that is, in the vertical direction in the drawing is formed. The step 3
3d is locked by a locking edge 22 formed on the outer blade case 20 and functions to prevent the outer blade case 20 from coming off. Further, on the guide wall 33b, locking protrusions 33c for preventing rotation are formed which are projected downward in the figure and are spaced apart from each other.
Locking protrusion 23 formed on the outer blade case 20 between 3c
Is positioned, and the locking projection 33c is locked to the locking projection 23 so that the outer blade 30 is prevented from rotating.

Further, the central frame 34 has a through hole 13 formed in the inner blade base 10 and a centering hole 35 having an axial center coinciding with the axial center of the output shaft 7 of the motor in the central portion thereof. When the tip portion of the output shaft 7 is fitted in the centering hole 35, the outer blade 30 is positioned at the center position by the output shaft 7. Further, when the output shaft 7 is inserted into the through hole 13 as well, the center of rotation of the inner blade base 20 is positioned by the output shaft 7. Therefore, the output shaft 7 is located in the through hole 13 of the inner blade base 10. When the tip end of the inner cutter 10 penetrates through the center of the outer cutter 30 and is fitted in the centering hole 35 of the central frame 34 of the outer cutter 30, the center of rotation of the inner cutter base 10 and the center of the outer cutter 30 are defined by the output shaft 7. Positioning is performed with the axes aligned. That is, the inner blade base 10 rotates about the centering hole 35 of the outer blade 30 via the output shaft 7, and therefore the blade body 17 a of the inner blade 17 that rotates integrally with the inner blade base 10. The rotation locus of is constant, and the blade body 17a is always in sliding contact with a constant surface of the outer blade 30, that is, the inner peripheral surface of the blade plate 32.

The outer blade 30 is attached to the outer blade case 20 by inserting the outer blade 30 from the lower side in the drawing and between the engaging edge 22 and the engaging protrusion 23 of the outer blade case 20, that is, the fitting recess. 25, the guide wall 33 of the outer peripheral frame 33 of the outer blade 30
This is done by positioning and storing b. Since the guide wall 33b is positioned in the fitting recess 25 and the outer blade 30 is attached to the outer blade case 20, the guide wall 33b is positioned in the fitting recess 25 with a gap G. The outer blade 30 is movable in the fitting recess 25 in the vertical direction in the figure. The outer blade 30 is configured to be vertically movable within the fitting recess 25 of the outer blade case 20 when the outer blade 30 is attached to the outer blade case 20 as described above. 30 That is, when the pressing force received from the skin by the blade plate 32 becomes abnormally large, the outer blade 30 is moved downward to absorb the abnormal pressing force and prevent the blade plate 32 from being deformed. This is to prevent damage to the blade.

Further, the gap G is set to be smaller than the fitting margin between the tip end portion of the output shaft 7 and the centering hole 35 formed in the central frame 34, and when the outer blade 30 moves downward, The tip of 7 does not come off from the centering hole 35.

Then, as shown in FIG. 1, the inner blade 17 is attached to the fitting shaft 8 attached to the output shaft 7 of the motor 3 while allowing the tip of the output shaft 7 to penetrate the through hole 13. After fitting and mounting the fitting hole 11 of the inner blade base 10,
The electric razor is assembled in a use state by screwing the outer blade case 20 to which the outer blade 30 is attached to the annular wall 4a of the storage chamber 4 and attaching the outer blade case 20 to the main body case 2. Then, when assembled in the above-described use state, the outer blade 30 is urged upward by the leaf spring 19 through the inner blade 17 movably attached to the inner blade base 10 to cause the outer peripheral frame to move. The stepped portion 33d formed in 33 is pushed up to a position where it is locked by the locking edge 22, and the locking projection 23 and the lower surface of the outer peripheral frame 33 are separated by a gap G as shown in FIGS. It is in a separated state. Also,
The leaf spring 19 when assembled in the use state in this way
The urging force is set to a predetermined urging force, that is, an urging force most suitable for normal shaving (generally, an optimum urging force is about 2N (Newton)).

In the state assembled in this way, the output shaft 7 of the motor 3 has the inner blade base 10
Through the through hole 13 and the tip end thereof is fitted into the centering hole 35 of the central frame 34 of the outer blade 30. As a result, as described above, the center of rotation of the inner blade base 10 and the outer blade 30. Since the center of the outer cutter 30 and the center of rotation of the inner cutter 10 are positioned with the output shaft 7 as a direct reference, the center of the inner cutter 10 and the center of the inner cutter 10 are aligned with each other. The blade body 17a of the inner blade 17 that rotates integrally is the blade plate 3
The two spherical inner peripheral surfaces rotate without sliding contact on the same peripheral surface. Therefore, it is possible to prevent a gap from being generated between the blade body 17a of the inner blade 17 and the inner peripheral surface of the blade plate 32 of the outer blade 30, and to make a slidable contact with high accuracy, and thus a good shaving can be performed.

A clearance for fitting the fitting hole 11 formed in the inner blade stand 10 with the fitting shaft 8 fitted in the fitting hole 11 and the through hole 13 formed in the inner blade stand 10 and the motor. 3 by increasing the fitting clearance with the output shaft 7, that is, by determining the rotation center of the inner blade base 10 by the through hole 13 and the output shaft 7 inserted into the through hole 13. Even if the center of the outer diameter of the fitting shaft 8 and the center of the through hole 8a formed inside do not coincide with each other, the inner cutter base 10 is displaced from the true center axis of the fitting shaft 8. The inner blade base 10 does not rotate around the central axis, that is, the central axis deviated from the axis of the output shaft 7, and therefore the blade body 17a of the inner blade 17 and the blade plate 32 of the outer blade 30.
The shaving can be performed well because the inner peripheral surface of the slab comes into sliding contact with high precision.

Next, the operation of the electric shaver constructed as above will be described. Storage room 4 for shaving
After the inner blade base 10 having the inner blade 17 mounted therein is mounted by fitting the fitting hole 11 into the fitting shaft 8, the outer blade 30
The outer blade case 20 in which is stored is screwed and attached to the annular wall 4a of the storage chamber 4, and is assembled into a use state as shown in FIG. In this assembled state, as described above, the outer blade 30 is urged by the leaf spring 19 through the inner blade 17 and the locking edge 2 is moved.
2 is pushed upward to the position where the step portion 33d and the step portion 33d are locked, and the fitting shaft 8 attached to the output shaft 7 of the motor 3 is fitted into the fitting hole 11 of the inner blade base 10. At this time, the notch 8b of the fitting shaft 8 engages with the engaging projection 12 and the inner blade base 10 rotates together with the fitting shaft 8. Further, the output shaft 7 is inserted through the through hole 13 of the inner blade base 10 and fitted into the centering hole 35 of the central frame 34 of the outer blade 30 at the tip portion thereof.

Then, a power switch (not shown) is closed and the blade plate 32 of the outer blade 30 is pressed against the skin of the face to move, thereby shaving. The shaving is performed by pressing the outer blade 30 against the skin during the shaving, and the blade body of the inner blade 17 that rotates while slidingly contacting the inner peripheral surface of the blade plate 32 of the outer blade 30 during the shaving. Since 17a makes sliding contact with the inner peripheral surface of the blade plate 32 of the outer blade 30 with the centering hole 35 formed in the central frame 34 of the outer blade 30 by the output shaft 7 as the center of rotation, the same surface of this inner peripheral surface is always maintained. It will be in sliding contact.
Therefore, the blade body 17 a of the inner blade 17 and the blade plate 3 of the outer blade 30
The inner peripheral surface of No. 2 is brought into sliding contact with high accuracy, and good shaving is achieved.

The outer blade 30 is constantly pressed by the skin when shaving. When the pressing force exceeds a predetermined value, that is, an abnormal pressing force, the outer blade 30 is attached with the leaf spring 19. As shown in FIG. 8, the blade plate 32 is moved against the force to the inner blade base 10 side, and the abnormal pressing force is absorbed to prevent the blade plate 32 from being deformed. When the user releases the abnormal pressing force, the outer blade 30 moves upward and returns to the normal position. In this way, the outer blade 30 moves in the vertical direction during shaving, but even if the outer blade 30 moves in the vertical direction, the tip of the output shaft 7 still has the outer blade 30.
Since it is fitted in the centering hole 35 of the central frame 34, the inner blade base 10 rotates about the centering hole 35 of the outer blade 30 via the output shaft 7 as described above. Inner blade 1
The blade body 17a of No. 7 and the inner peripheral surface of the blade plate 32 of the outer blade 30 are brought into slidable contact with each other with high precision, and good shaving is performed. Even if the outer blade 30 receives a pressing force of a predetermined amount or more and moves to the inner blade base 10 side, as described above, the tip end portion of the output shaft 7 is not separated from the centering hole 35 formed in the central frame 34. Instead, the inner blade base 10 rotates about the centering hole 35 as the center of rotation via the output shaft 7.

As described above, in the assembled state of use, the fitting shaft 8 attached to the output shaft 7 of the motor 3 fits into the fitting hole 11 of the inner blade base 10 and the output shaft 7 Since the through hole 13 is inserted and the tip end thereof is fitted into the centering hole 35 of the central frame 34 of the outer blade 30, the inner blade base 1
0 rotates around the centering hole 35 of the outer blade 30 via the output shaft 7, and the blade body 17a of the inner blade 17 always keeps the same portion of the inner peripheral surface of the blade plate 32 of the outer blade 30. Therefore, the blade body 17a of the inner blade 17 and the outer blade 3 are in sliding contact with each other.
The inner peripheral surface of the blade plate 32 of 0 comes into sliding contact with high precision, and good shaving is performed.

Further, the fitting hole 1 formed in the inner blade base 10
1, the fitting clearance between the fitting shaft 8 fitted into the fitting hole 11 and the through hole 13 formed in the inner blade base 10 and the output shaft 7 of the motor 3 is increased. Then, even if the center of the outer diameter of the fitting shaft 8 and the center of the through hole 8a formed inside do not match, that is, even if the dimensional accuracy of the fitting shaft 8 varies. This variation due to the clearance causes the inner blade 1
Regardless of the center of rotation of 0, the inner cutter base 10 does not rotate about the true center axis of the fitting shaft 8, that is, the center shaft displaced from the center shaft of the output shaft 7, as the center of rotation. Therefore, the blade body 17a of the inner blade 17 and the inner peripheral surface of the blade plate 32 of the outer blade 30 are brought into slidable contact with each other with high precision, and good shaving can be performed.

In the above embodiment, the rotational force of the output shaft 7 of the motor 3 is transmitted to the inner blade base 10 by stopping the rotation of the fitting shaft 8 provided with the notch 8b as an engaging portion on the output shaft 7. On the other hand, the inner blade base 10 is provided with a fitting hole 11 for fitting with the fitting shaft 8, and the notch 8 is provided in the fitting hole 11.
By providing the engagement protrusion 12 as an engaged portion that engages with b,
This is done by engaging the engaging projection 12 and the notch 8b, but this is done without providing the fitting shaft 8 by attaching an engaging pin to the output shaft 7 in a direction orthogonal to the axial direction. Further, a protrusion or a concave groove that engages with the engaging pin is provided on the lower surface of the inner blade base 10 to be an engaged portion, and the output pin 7 is engaged by engaging the engaging pin with the protrusion or the concave groove. It is also possible to adopt a configuration in which the rotational force is transmitted to the inner blade base 10.

As a method of providing the engaging portion on the output shaft 7, the engaging shaft 8 or the engaging pin having the engaging portion provided separately from the output shaft 7 as described above is provided. Instead, the output shaft 7 is directly formed on the output shaft 7 as described above to form a D-shape or a key groove as an engaging portion, and the shape of the fitting hole 11 of the inner blade base 10 is changed to that of the output shaft 7. The engaged portion, that is, the engaged portion, can be made to correspond to the shape.

[0034]

Since the invention according to claim 1 is configured as described above, a centering hole is formed in the central frame provided in the central portion of the outer blade, and the engaged portion and the core are provided in the inner blade base. An output hole is provided, and the engaging portion attached to the output shaft of the motor is engaged with the engaged portion, the output shaft of the motor is inserted into the centering hole, and the tip portion is fitted into the centering hole. Since the center of rotation of the inner blade and the center of the outer blade are made to coincide with each other by the output shaft of the motor, the centering shaft is not required, and the number of parts and the assembly man-hour can be reduced, and the inner blade The effect is that the center of rotation of and the center of the outer blade can be accurately aligned.

Further, according to a second aspect of the present invention, a centering hole is formed in a central frame provided in a central portion of the outer blade, and a fitting hole and a centering hole having an engaged portion on the inner blade base are formed. And a fitting shaft having an engaging portion attached to the output shaft of the motor is fitted into the fitting hole, and the output shaft of the motor is inserted into the centering hole, and the tip end thereof is aligned with the centering hole. The configuration is such that the center of rotation of the inner blade and the center of the outer blade are made to coincide with each other by the output shaft of the motor, so a centering shaft is not required and the number of parts and the number of assembly steps can be reduced. Since the clearance between the fitting hole of the inner blade base and the fitting shaft fitted in this fitting hole is made larger than the clearance between the centering hole and the output shaft inserted in this centering hole, Even if there is a discrepancy between the axis of the outer diameter and the axis of the fitting hole of the inner blade, in other words, the dimensions of the fitting shaft The center of rotation of the inner blade can be accurately positioned by the output shaft of the motor without being affected by these variations, and therefore the center of rotation of the inner blade and the center of the outer blade can be more accurately As a result, the blade body of the inner blade and the inner peripheral surface of the outer blade can be brought into slidable contact with each other with high precision, and good shaving can be achieved.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a rotary electric shaver according to an embodiment of the present invention.

FIG. 2 is a plan view of the inner cutter base of the above embodiment.

FIG. 3 is a partial cross-sectional view (Y-Y cross-sectional view in FIG. 2) showing a mounting state of the inner blade of the above embodiment on the inner blade base.

FIG. 4 is a plan view of the inside of the outer blade of the above embodiment.

FIG. 5 is a cross-sectional view of the central frame of the outer blade of the above embodiment.

FIG. 6 is a partial cross-sectional view showing the relationship between the outer blade and the outer blade case of the above embodiment.

FIG. 7 is an exploded view of the rotary electric shaver of the above embodiment.

FIG. 8 is a partial cross-sectional view showing a state in which the outer cutter of the embodiment is moved to the inner cutter stand.

FIG. 9 is a cross-sectional view of a part of a conventional rotary electric shaver.

[Explanation of symbols]

 1 Main body 3 Motor 4 Inner blade base storage chamber (storage recess) 7 Output shaft 8 Fitting shaft 8a Notch (engaged part) formed in fitting shaft 10 Inner blade base 11 Fitting hole formed in inner blade base 12 Engagement protrusion (engagement portion) formed in the fitting hole 13 Through hole (centering hole) 14 Inner blade mounting hole 17 Inner blade 17a Blade body 17b Engagement hole (engagement portion) 19 Leaf spring (elastic body) 20 Outer Blade Case 30 Outer Blade 33 Outer Perimeter Frame 34 Central Frame 35 Centering Hole

Claims (2)

[Claims] 1. A central frame having a storage recess formed in a circular recess having an opening at one end side and a centering hole formed in the center of a blade plate having a large number of whisker introducing holes, and an outer peripheral frame being an outer peripheral part. An outer blade provided to close the opening of the accommodation recess and attached, and a motor having an output shaft provided in the main body and protruding from the bottom of the accommodation recess to fit its tip into the centering hole. A core through which the output shaft is inserted on the outer blade side with an engaging portion provided on the output shaft of the motor for transmitting a rotational force and an engaged portion engaging with the engaging portion on the bottom side of the storage recess. An inner blade base having an exit hole and a plurality of inner blade mounting holes formed around the center hole, and one end slidably provided in the inner blade mounting hole and located on the outer blade side. Inner blade with a blade on one side and an engaging part on the other side, and one end attached to the inner blade base Re rotary electric shaver, characterized in that the engaged inner cutter in the engaging portion and the other end provided with an elastic member for biasing said outer cutter side. 2. A storage frame formed in a circular recess having an opening on one end side and a central frame having a centering hole formed in the central part of a blade plate having a large number of whisker introducing holes, and an outer peripheral frame being an outer peripheral part. A motor having an outer blade that is attached by closing the opening of the storage recess, and an output shaft that is provided in the main body and that protrudes from the bottom of the storage recess and fits its tip into the centering hole. And a fitting shaft having an engaging portion that is inserted into the output shaft of the motor so as not to rotate and that transmits a rotational force, and an engaged portion that engages with the engaging portion on the bottom side of the storage recess. A fitting hole into which the fitting shaft is inserted, and a centering hole communicating with the fitting hole on the outer blade side and through which the output shaft is inserted, and surrounding the centering hole. Inner blade base with multiple inner blade mounting holes, and slidably mounted on the inner blade mounting holes An inner blade having a blade body formed on one end side located on the outer blade side and an engagement portion formed on the other end side, and one end attached to the inner blade base and the other end engaged with the engagement portion. The clearance between the fitting hole formed in the inner blade base and the fitting shaft fitted in the fitting hole is formed by the elastic body that urges the inner blade toward the outer blade, and the centering hole is provided. A rotary electric razor characterized in that the clearance of the output shaft inserted through the centering hole is formed large.