Electric shaver

A height dimension D1 of a head section 4 is smaller than a front-back dimension D2 of the head section 4. The head section 4 has therein a linear actuator 12 as a drive source. Inner blades 13 are coupled to a drive coupling section protruding form an actuator main section. A height dimension of the actuator main section is smaller than a front-back dimension of the actuator main section.

FIELD OF THE INVENTION

RELATED APPLICATIONS

This application is a U.S. National Stage application of PCT/JP2010/066332, filed on Sep. 21, 2010, which claims priority to Japanese Patent Application No. 2009-220456, filed on Sep. 25, 2009, the entirety of which is incorporated herein.

The present invention relates to an electric shaver used to shave body hair such as facial hair.

BACKGROUND OF THE INVENTION

A conventional electric shaver is equipped with a body section incorporating a power source and a head section supported by the body section. The head section has outer blades at the upper end thereof. The outer blades are structured to draw in body hair. The outer blades are aligned in a front-back direction and are parallel with one another. Inner blades are provided on inner sides of the outer blades. The inner blades are driven by a drive source. Patent Document 1 discloses an electric shaver in which a head section swings relative to a body section in at least one of forward, backward, rightward, and leftward directions. Conventionally, a swing shaft of the head section is provided near the outer blades at the upper end of the head section. According to the structure, when a user presses the outer blades to his skin while holding the body section, the head section swings to allow the outer blades to follow the skin, improving the shaving performance.

PRIOR ART DOCUMENT

Patent Document

SUMMARY OF THE INVENTION

The conventional electric shaver is desirably improved such that the head section has a better ability to follow the skin.

The objective of the present invention is to provide an electric shaver in which the ability of a head section to follow the skin is improved.

To achieve the foregoing objective and in accordance with a first aspect of the present invention, an electric shaver is provided that includes a body section incorporating a power source and a head section supported by the body section and configured to swing relative to the body section in at least one of forward, backward, rightward, and leftward direction. The head section has a plurality of outer blades at the upper end thereof. The outer blades are aligned in a front-back direction, parallel with each other and configured to draw in body hair, and an inner blade driven by a drive source being provided on the inner side of each outer blade. A height dimension of the head section is smaller than a front-back dimension of the head section. The drive source includes a linear actuator provided in the head section. The linear actuator has an actuator main section and a drive coupling section protruding from the actuator main section and coupled to the inner blades. A height dimension of the actuator main section is smaller than a front-back dimension of the actuator main section.

According to the present invention, the height dimension of the head section is smaller than the front-back dimension of the head section. The ratio of the height dimension to the front-back dimension of the head section is correlative to the heightwise position of the center of gravity of the head section. In other words, when the head section is formed to have a height dimension smaller than its own front-back dimension, the center of gravity of the head section can be located near the upper end of the head section. A swing shaft is located near the upper end of the head section where the outer blades are provided. Therefore, when the head section is formed to have a height dimension smaller than its own front-back dimension, the center of gravity of the head section can be located near the swing shaft of the head section. This improves the ability of the head section to follow the skin. In the actuator main section of the linear actuator configured to drive the inner blades, the height dimension is similarly smaller than the front-back dimension. This facilitates reduction in the height dimension of the head section incorporating the linear actuator to values smaller than the front-back dimension of the head section. This further improves the ability of the head section to follow the skin.

The actuator main section preferably includes a movable element and a stator that includes a plurality of coils, and the coils are preferably aligned in a direction orthogonal to the height direction of the actuator main section and are parallel with each other.

The present invention thus can reduce the height dimension of the actuator main section without undermining the driving force of the linear actuator.

The coils are preferably aligned in a front-back direction of the actuator main section and are parallel with each other.

The present invention facilitates reduction in the height dimension of the actuator main section to values smaller than the front-back dimension of the actuator main section.

Each coil is preferably situated with the axis thereof extending in the direction orthogonal to the height direction of the actuator main section, and the movable element preferably faces the coils along a direction orthogonal to the height direction of the actuator main section.

The present invention is structurally characterized in that the movable element of the actuator main section is facing the coils in a direction orthogonal to the height direction. This leads to further downsizing of the actuator main section in the height direction.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Hereinafter, a three-blade electric shaver according to a first embodiment of the present invention will be is described referring toFIGS. 1 to 4.

As illustrated inFIG. 1, an electric shaver1is equipped with a body section3incorporating a power source2, and a head section4provided at the upper end of the body section3. The body section3has a supporting portion3aprovided in the upper end thereof to support the head section4. The head section4swings in the supporting portion3ain a front-back direction X with a support shaft S as a swing axis. The head section4has three outer blades11formed from thin metal plates at the upper end thereof. The outer blades11are aligned in the front-back direction X and are parallel with one another. The outer blades11respectively have a plurality of holes formed to draw in body hair. The outer blades11are secured to a resin support frame not illustrated in the drawings. The blades11and the resin support frame constitute an outer blade block. A swing shaft (support shaft S) of the head section4is located near the outer blades11. More specifically, the swing shaft of the head section4is located near the upper end of a housing member in which the head section4is housed. An inner blade13is provided on the inner side of each outer blade11. The inner blades13are configured to reciprocate in a right-left direction Y which is a direction orthogonal to the drawing plane inFIG. 1. The head section4incorporates a linear actuator12. The inner blades13are reciprocated by the linear actuator12. The front-back direction X, a right-left direction Y, and a height direction Z are orthogonal to one another.

The linear actuator12is electrically connected to the power source2. The linear actuator12is driven when an operation switch provided in the body section3(not illustrated in the drawings) is operated. When body hair such as facial hair is drawn in through the holes formed in the outer blades11, the body hair is nipped by the outer blades11and the reciprocating inner blades13to be cut. When a user presses the outer blades11of the head section4to his skin while holding the body section3, the head section4swings in the front-back direction X to let the outer blades11follow the skin.

[Structure of Linear Actuator]

As illustrated inFIGS. 2 to 4, the linear actuator12is equipped with an actuator main section21and two drive coupling sections22. The two drive coupling sections22both protrude upward from the actuator main section21.

As illustrated inFIG. 3, a stator26including an iron core23and a pair of coils24and25is provided in a center part of the actuator main section21as viewed in the height direction Z. The iron core23is securely pinched in the right-left direction Y by a first pair of stator-side support portions27aand a second pair of stator-side support portions27b. The first stator-side support portions27aand the second stator-side support portions27bare aligned in the front-back direction X and are parallel with each other. The iron core23has a base section23aextending in the right-left direction Y, tooth sections23brespectively extending forward and backward from the center of the base section23a, and extending sections23cextending forward and backward respectively from both ends of the base section23a. The coils24and25are wound about the tooth sections23b, respectively. The coils24and25are situated with axes thereof extending in the front-back direction X. The coils24and25are located between the extending sections23cprovided in a pair. The coils24and25are electrically connected to the power source2via connection terminals (not shown) provided in coils24and25so that the coils24and25are fed with power from the power source2.

A movable element31is provided near one of the front end and the rear end of the stator26, and a movable element32is provided near the other one of the front and rear ends. The movable element31has a yoke34supported by a first movable element-side support portion33aand a magnet35secured to the yoke34. The magnet35of the movable element31is facing the coil24. The movable element32has a yoke34supported by a second movable element-side support portion33band a magnet35secured to the yoke34. The magnet35of the movable element32and the coil25are facing each other. The magnet35of the movable element32is facing the coil25. A magnetic field action generated by the power fed to the coil24makes the movable element31reciprocate with the first movable element-side support portion33ain the right-left direction Y. A magnetic field action generated by the power fed to the coil25causes the movable element32to reciprocate with the second movable element-side support portion33bin the right-left direction Y.

The respective first stator-side support portions27aand the first movable element-side support portion33aare coupled to each other by suspension springs41at both ends thereof in the right-left direction Y. The respective second stator-side support portions27band the second movable element-side support portion33bare similarly coupled to each other by suspension springs42at both ends thereof in the right-left direction Y. The actuator main section21has linear coupling springs43provided at both ends thereof in the right-left direction Y. The first and second movable element-side support portions33aand33bare coupled to each other by linear coupling springs43. The linear coupling springs43allow reciprocating vibration of the first and second movable element-side support portions33aand33bin the right-left direction Y.

The movable elements31and32provided in a pair are respectively coupled to the drive coupling sections22to move integrally with the drive coupling sections22. The drive coupling sections22are coupled to the inner blades13. Therefore, driving of the movable elements31and32is started when the coils24and25are fed with power. When driving forces of the movable elements31and32are transmitted to the inner blades13by way of the drive coupling sections22, the inner blades13start to vibrate in a reciprocating manner.

As illustrated inFIG. 1, the head section4of the electric shaver1has a height dimension D1and a front-back dimension D2. The height dimension D1is smaller than the front-back dimension D2. The ratio of the height dimension D1to the front-back dimension D2is correlative to the heightwise position of the center of gravity G of the head section4. Specifically, the position of the center of gravity G of the head section4is elevated as the height dimension D1of the head section4is made smaller than the front-back dimension D2. In other words, in the electric shaver1, in which the height dimension D1of the head section4is smaller than the front-back dimension D2, the center of gravity G of the head section4can be set near the upper end of the head section4, which is near the swing shaft (support shaft S). This improves the ability of the head section4to follow the skin. The height dimension D1of the head section4is more specifically the height dimension of the head section4from a lower end4aof the head section4to the upper end of the outer blades11.

As illustrated inFIG. 4, a height dimension D3of the actuator main section21is smaller than a width dimension D4of the actuator main section21. This facilitates reduction in the height dimension D1of the head section4to values smaller than the front-back dimension D2, thereby further improving the ability of the head section4to follow the skin. The actuator main section21does not include the connection terminals of the coils24and25.

The first embodiment has the following advantages.

(1) In the head section4, the height dimension D1is smaller than the front-back dimension D2. Therefore, the center of gravity G of the head section4can be located near the upper end of the head section4. In the head section4, the swing shaft (support shaft S) is located near the upper end of the head section4where the outer blades11are provided. Therefore, the center of gravity G of the head section4can be located near the swing shaft of the head section4as far as the height dimension D1of the head section4is smaller than the front-back dimension D2. This improves the ability of the head section4to follow the skin. The actuator main section21of the linear actuator12, which is configured to drive the inner blades13, similarly has the height dimension D3smaller than the front-back dimension D4. Accordingly, the height dimension D1of the head section4incorporating the linear actuator12can easily be reduced to values smaller than the front-back dimension D2. This further improves the ability of the head section4to follow the skin.

(2) In the stator26of the actuator main section21, the coils24and25are aligned in the direction orthogonal to the height direction Z and are parallel with each other. This succeeds in reducing the size of the actuator main section21in the height direction Z without undermining the driving force of the linear actuator12.

(3) The coils24and25are aligned in the front-back direction X and are parallel with each other. This facilitates to reduce the height dimension D3of the actuator main section21to values smaller than the front-back dimension D4.

(4) The coils24and25are situated with the axes thereof extending in the front-back direction X. The movable elements31and32of the actuator main section21are respectively facing the coils24and25in the front-back direction X. This leads to a further reduction in the size of the actuator main section21in the height direction Z.

Hereinafter, a second embodiment of the present invention, in which the electric shaver according to the present invention is applied to a five-blade electric shaver, is described with reference toFIGS. 5 to 7. Any structural elements according to the second embodiment configured similarly to those of the first embodiment will not be described in detail.

As illustrated inFIG. 5, an electric shaver51is equipped with a body section53incorporating a power source52, and a head section54provided at the upper end of the body section53. The head section54swings in a front-back direction X with a support shaft S as a swing axis. The head section54has five outer blades61at the upper end thereof. The outer blades61are aligned in the front-back direction X and are parallel with one another. An Inner blade63is provided on the inner side of each outer blade61. The inner blades63are configured to be reciprocated by a linear actuator62provided in the head section54.

As illustrated inFIGS. 6 and 7, an iron core73and a coil74wound around tooth sections of the iron core73in a center part of an actuator main section71. The coil74is situated with an axis thereof extending in a height direction Z. In the center part of the actuator main section71, a pair of magnets85having a flat-plate shape constituting a movable element is provided at a position facing the upper end surface of the coil74. The magnets85are situated with the thickness direction thereof directed toward the axis of the coil74. More specifically, the magnets85are situated such that the surfaces thereof are orthogonal to the axis of the coil74. When the coil74is fed with power, the movable element starts to be driven, and the inner blades63vibrate in a reciprocating manner with a drive coupling section72.

As illustrated inFIG. 5, the head section54of the electric shaver51has a height dimension D1smaller than a front-back dimension D2thereof. The ratio of the height dimension D1to the front-back dimension D2is correlative to a heightwise position of the center of gravity G of the head section54. Specifically, the position of the center of gravity G of the head section54can also be located near the upper end of the head section54, that is, the center of gravity G can be located near the swing shaft (support shaft S). As illustrated inFIGS. 6 and 7, the actuator main section71has a height dimension D3smaller than a front-back dimension D4thereof. This facilitates to reduce the height dimension D1of the head section54to values smaller than the front-back dimension D2.

The second embodiment has the following advantages.

(5) In the head section54, the height dimension D1is smaller than the front-back dimension D2. Therefore, the center of gravity G of the head section54can be located near the upper end of the head section4. In the actuator main section71, the height dimension D3is smaller than the front-back dimension D4, facilitating to reduce the height dimension D1of the head section54to be smaller than the front-back dimension D2. This further improves the ability of the head section54to follow the skin. Thus, according to the present invention, the five-blade electric shaver51achieves advantages similar to those of the three-blade electric shaver1.

(6) According to the second embodiment, the coil74is situated with the axis thereof extending in the height direction Z, and the flat magnets85are situated so that their surfaces are orthogonal to the axis of the coil74. According to such a structure, when the dimensions of the magnets85in the front-back direction X are set to large values, the size of the actuator main section71can be reduced in the height direction Z, and the linear actuator62can still maintain an expected driving force. The movable element including the magnets85achieves a better weight balance and driving balance as compared to a movable element with one magnet.

According to the first embodiment, the coils24and25are aligned in the front-back direction X and are parallel with each other. However, the coils24and25may be aligned in the right-left direction Y and parallel with each other.

According to the first embodiment, the movable elements31and32of the actuator main section21are respectively facing the coils24and25in the front-back direction X. However, the movable elements31and32may be provided to face the coils24and25in the right-left direction Y.

The head sections4and54according to the exemplary embodiments described so far are configured to swing in the front-back direction X. However, the head sections4and54may be configured to swing in the right-left direction Y or swing in the front-back direction X and the right-left direction Y both.

The present invention is not limitedly applicable to the three- and five-blade electric shavers but is also applicable to other electric shavers.

The inner blades13and63according to the exemplary embodiments described so far may be a screw blade or a rotary blade.

The movable element having the magnets85according to the second embodiment may be replaced with a movable element having only one magnet.