Ultrasonic cosmetic treatment device

Since the electrical impedance of an ultrasonic vibrator may vary according to the contact or non-contact of an application member with the skin, a detection circuit detects the contact or non-contact of the application member with the skin by converting the current the ultrasonic vibrator current into a voltage, and a comparator compares this voltage with a reference voltage. When contact is detected by the detection circuit, a constant-voltage circuit sets the level of the constant voltage output to the ultrasonic oscillation circuit at a standard voltage, but when non-contact is detected, the constant voltage is switched to a lower-level constant voltage. Thus, when non-contact is detected, the level of the ultrasound emitted from the ultrasonic vibrator via the application member is lowered, so that an unnecessary rise in the temperature of the application member is be prevented.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention relates to an ultrasonic cosmetic treatment device,
 and more specifically, to an ultrasonic cosmetic treatment device for
 encouraging the permeation of cosmetics into the skin.
 2. Description of Relevant Materials
 Registered Utility Model (Japanese) Gazette No. 3013614 (published May 10,
 1995) describes one example of a conventional ultrasonic cosmetic
 treatment device. This conventional device is intended to achieve the
 effect of promoting the permeation of the cosmetic into the skin with an
 application of ultrasound. That is, after a specified cosmetic is applied
 to the face (or other skin area), a probe is used to apply ultrasound to
 the area of cosmetic application. In the conventional device, ultrasound
 is constantly output from the probe, whether or not the skin-contacting
 surface of the probe is actually in contact with the skin.
 However, in the conventional device, although ultrasonic vibrations are
 propagated if the skin-contacting surface of the probe is in contact with
 the skin, ultrasonic vibrations are not propagated if the probe is placed
 against the skin in an improper manner. Accordingly, when the probe is
 placed against the skin in an improper manner, the intended effect is not
 satisfactorily achieved. Furthermore, since ultrasound is emitted at the
 same output value (set by the user) whether the probe is in contact with
 the skin or not, the probe generates heat when it is not in contact with
 the skin. That is, when the probe is not in contact with the skin, the
 vibration-propagating portion of the probe (which is preferably formed
 mainly from metal) generates heat as a result of the vibration. The
 temperature of this portion rises, causing discomfort. Furthermore, even
 if the ultrasonic vibrator undergoes abnormal oscillation during the
 generation of ultrasound, the user is unaware of the abnormal oscillation
 until the probe is placed against the skin.
 SUMMARY OF THE INVENTION
 An object of the invention is to provide an ultrasonic cosmetic treatment
 device that suppresses unnecessary rise in the temperature of the portion
 of the probe that contacts the skin, e.g., when the probe is not in
 contact with the skin.
 Another object of the invention is to provide a safe ultrasonic cosmetic
 treatment device, i.e., a device that prevents the application of abnormal
 ultrasound to the user's skin.
 In order to achieve the abovementioned objects, according to one aspect of
 the invention, an ultrasonic cosmetic treatment device includes a probe
 having an application member with a skin-contacting surface. An ultrasonic
 vibrator is attached to the opposite side of the application member from
 the skin-contacting surface. Circuits are provided in a housing,
 including: an ultrasonic oscillation circuit having an oscillation output
 for driving the ultrasonic vibrator and a detection circuit that detects
 contact and non-contact of the application member with the skin. An
 oscillation control circuit lowers a level of the oscillation output in
 response to a change from contact to non-contact of the application member
 with the skin, and increases the level of the oscillation output in
 response to a change from non-contact to contact of the application member
 with the skin.
 Preferably, the application member is formed from metal.
 Consequently, when the application member is not in contact with the skin,
 the level of the ultrasound that is emitted from the ultrasonic vibrator
 via the application member is lowered. Unnecessary rise in the temperature
 of the application member which contacts the skin is thereby suppressed.
 In one modification, when the change from contact to non-contact of the
 application member with the skin is detected by the detection circuit, the
 oscillation control circuit lowers a level of the oscillation output after
 a predetermined delay time has elapsed.
 In this case, the level of the ultrasound that is emitted from the
 ultrasonic vibrator via the application member is lowered only in the case
 of non-contact for a period longer than a predetermined delay time.
 Accordingly, even if the contacting state of the application member with
 the skin varies frequently during use, unnecessary increase or decrease in
 the level of the ultrasound is prevented.
 In another modification, the ultrasonic cosmetic treatment device also
 includes a display that displays the status of contact or non-contact of
 the application member of the probe with the skin in accordance with
 detection results obtained by the detection device. Preferably, the
 display switches from a status display of contact to one of non-contact
 after a predetermined delay time has elapsed since the change from contact
 to non-contact of the application member with the skin is detected by the
 detection circuit.
 As a result, the user is informed by the display of the contact or
 non-contact of the application member with the skin.
 Furthermore, if the display switches from a contact display to a
 non-contact display only in the case of non-contact for a period exceeding
 a predetermined delay time, unnecessary display switching is prevented,
 even in cases where the contacting state of the application member with
 the skin varies frequently during use.
 In a further modification, the oscillation control circuit includes a pulse
 oscillation circuit that outputs a control pulse signal that controls the
 application time of the oscillation output from the ultrasonic oscillation
 circuit to the ultrasonic vibrator. In this case, the ultrasonic cosmetic
 treatment device preferably includes a device for stopping the oscillating
 operation of the ultrasonic oscillation circuit when abnormalities occur
 in the control pulse signal output by the pulse oscillation circuit.
 Accordingly, when abnormalities occur in the control pulse signal, no
 ultrasound is emitted from the ultrasonic vibrator, so that the
 application of undesirable abnormal ultrasound to the skin is prevented.
 In another aspect of the invention, an ultrasonic cosmetic treatment device
 for application to the skin includes an ultrasonic vibrator probe for
 contacting the skin. An ultrasonic oscillation circuit vibrates the
 ultrasonic vibrator probe, and a detection circuit detects contact of the
 ultrasonic vibrator probe with the skin. An oscillation control circuit
 changes a level of vibration of the ultrasonic vibrator probe when the
 detection circuit detects a change in contact of the ultrasonic vibrator
 probe with the skin. The ultrasonic vibrator probe preferably includes an
 application member attached to an ultrasonic vibrator.
 In this case, the oscillation control circuit preferably lowers a level of
 the oscillation output in response to a change from contact to non-contact
 of the application member with the skin, and increases the level of the
 oscillation output in response to a change from non-contact to contact of
 the application member with the skin.
 More specifically, the detection circuit detects a change in contact of the
 ultrasonic vibrator probe with the skin by detecting a change in
 oscillation level caused by a change in impedance of the ultrasonic
 vibrator probe upon contact with the skin. The detection circuit may
 compare an envelope voltage of the oscillation level with a reference
 voltage to detect a change in contact of the ultrasonic vibrator probe
 with the skin.
 Thus, when the application member is not in contact with the skin, the
 level of the ultrasound that is emitted from the ultrasonic vibrator probe
 is lowered. Unnecessary rise in the temperature of the probe (which
 contacts the skin) is thereby suppressed.
 In one development of this aspect of the invention, a delay circuit is
 provided between the detection circuit and the oscillation control
 circuit. The delay circuit delays a signal from the detection circuit to
 the oscillation control circuit by a predetermined delay time, the
 oscillation control circuit thereby changing the level of vibration of the
 ultrasonic vibrator probe at the expiration of the predetermined delay
 time after the detection circuit detects a change in contact of the
 ultrasonic vibrator probe with the skin.
 Preferably, the delay circuit includes a delay timer that begins counting
 the predetermined delay time when non-contact of the ultrasonic vibrator
 probe with the skin is detected by the detection circuit. When contact of
 the ultrasonic vibrator probe with the skin is detected during the
 predetermined delay time, the delay timer is interrupted and the counting
 is restarted.
 Accordingly, the level of the ultrasound that is emitted from the
 ultrasonic vibrator probe is changed only in the case of a change in
 contact for a period longer than a predetermined delay time. Accordingly,
 even if the contacting state of the probe with the skin varies frequently
 during use, unnecessary changes in the level of the ultrasound are
 prevented.
 The ultrasonic cosmetic treatment device according to this aspect of the
 invention optionally includes a display connected to the detection circuit
 that changes when the detection circuit detects a change in contact of the
 ultrasonic vibrator probe with the skin. The display may include a
 non-contact display part and a contact display part, and turns on one of
 the non-contact display part and the contact display part when the
 detection circuit detects a change in contact of the ultrasonic vibrator
 probe with the skin.
 If a display is provided, a display delay circuit may also be provided that
 delays the change in the display by a predetermined delay time, the
 display thereby changing at the expiration of the predetermined delay time
 after the detection circuit detects a change in contact of the ultrasonic
 vibrator probe with the skin. In this case, the display delay circuit
 includes a delay timer that begins counting the predetermined delay time
 when a non-contact of the ultrasonic vibrator probe with the skin is
 detected by the detection circuit. When contact of the ultrasonic vibrator
 probe with the skin is detected during the predetermined delay time, the
 display delay timer is interrupted and the counting is restarted.
 As a result, the user is informed by the display of the contact or
 non-contact of the application member with the skin. Furthermore, if the
 display changes only when a change in the contacting state change persists
 for longer than a predetermined delay time, unnecessary display switching
 is prevented, even in cases where the contacting state of the application
 member with the skin varies frequently during use.
 In another development of this aspect of the invention, the ultrasonic
 cosmetic treatment device further includes a pulse oscillation circuit
 that outputs a control pulse signal that controls a vibration time of the
 ultrasonic vibrator probe, and a pulse-passing circuit that stops
 vibration of the ultrasonic vibrator probe when abnormalities occur in the
 control pulse signal output by the pulse oscillation circuit.
 In such a case, the pulse-passing circuit may pass only control pulse
 signals having less than a predetermined pulse length. Alternatively, if
 the control pulse signals remain at one level for longer than the
 predetermined pulse length, the pulse-passing circuit blocks the
 transmission of the control pulse signals, thereby suppressing the
 vibration of the ultrasonic vibrator probe.
 Accordingly, when abnormalities occur in the control pulse signal, no
 ultrasound is emitted from the ultrasonic vibrator probe, so that the
 application of undesirable abnormal ultrasound to the skin is prevented.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 FIG. 1 shows a block diagram of a first embodiment of the present
 invention. The ultrasonic cosmetic treatment device of the first
 embodiment includes a probe 3, including a housing 3a (shown in FIG. 2).
 The probe 3 has a metal application member 1 mounted thereto, and an
 external (skin-contacting) surface 1a of the application member 1 may be
 applied to the skin of a user. An ultrasonic vibrator 2 is provided
 (within the housing 3a) on the opposite side of the application member 1
 from the skin-contacting surface 1a.
 The application member 1 is preferably metal because if the density
 (uniformity) of the skin-contacting portion that transmits the vibration
 is uneven, vibration propagation anomalies may be produced in the
 vibration when ultrasonic longitudinal waves, propagate through the
 transmitting portion. Consequently, ultrasonic waves may not be
 transmitted as intended. If a molded part (e.g., non-metal) is used, weld
 and sink marks are produced, which may cause the density to be uneven.
 Further, the skin-contacting portion is preferably metal because it must
 have a certain degree of rigidity, so that it does not absorb longitudinal
 waves propagated therethrough. Although longitudinal waves propagate well
 through materials which have a high moisture content (e.g., gel), since it
 is impractical to construct durable and visually appealing cosmetic
 instruments from such materials, rigid materials (e.g., metal) are
 preferred.
 It is preferable that the thickness of the application member 1 be an
 integral multiple of the longitudinal wavelength propagated therethrough,
 i.e., that generated by the ultrasonic vibrator 2. In this respect, since
 a change in thickness will hinder efficient longitudinal wave propagation,
 a material that resists dimensional change is superior. In this respect,
 again, metal is preferred.
 As shown in FIG. 2, the housing 3a of the probe 3 includes a handle 3c
 (which is gripped by the user) and a main body 3b at the distal end of the
 handle 3c. The application member 1 is attached to the main body 3b.
 The application member 1 is formed in the shape of a cylinder with a bottom
 (e.g., an inverted cylindrical cup-shape). The ultrasonic vibrator 2
 (including, for example, a piezo-electric element) is bonded to the back
 side (opposite side) of the skin-contacting surface 1a of the application
 member 1. When the ultrasonic vibrator 2 is excited, the vibration of the
 ultrasonic vibrator 2 propagates through the application member 1, so that
 ultrasound is externally emitted from the skin-contacting surface 1a of
 the application member 1.
 As shown in FIG. 1, an ultrasonic oscillation circuit 4 drives the
 ultrasonic vibrator 2 via an (oscillation) output. It should be noted that
 the circuits of each of the first through fourth embodiments may be housed
 in a housing H separate from the probe 3. However, any circuits shown
 within the housing H may also be situated within the probe housing 3a. A
 detection circuit 5 connected to the ultrasonic oscillation circuit 2
 detects the contacting state (contact or non-contact) of the probe's
 application member 1 with the skin. An oscillation control circuit 6,
 connected to both the ultrasonic oscillation circuit 4 and the detection
 circuit 5, controls the ultrasonic oscillation circuit 4 in response to
 the output of the detection circuit 5. That is, when the contacting state
 of the application member 1 changes from "contact" to "non-contact" (as
 detected by the detection circuit 5), the level (e.g., amplitude) of the
 oscillation output from the ultrasonic oscillation circuit 4 to the
 ultrasonic vibrator 2 is lowered from the level when the application
 member 1 contacts the skin. Conversely, when the contacting state changes
 from "non-contact" to "contact" (as detected by the detection circuit 5),
 the level (e.g., amplitude) of the oscillation output from the ultrasonic
 oscillation circuit 4 to the ultrasonic vibrator 2 is increased from the
 level when the application member 1 does not contact the skin. That is,
 the level (e.g., amplitude) of the oscillation output is higher for
 "contact" than for "non-contact".
 The ultrasonic oscillation circuit 4 uses a well-known Colpitts oscillation
 circuit. The ultrasonic oscillation circuit 4 intermittently drives the
 ultrasonic vibrator 2 by applying an oscillating voltage Vc with a
 predetermined frequency (e.g., 1 MHZ) to the ultrasonic vibrator 2 via an
 electrical wire 20 (shown in FIG. 2) only while a control pulse signal Vb
 from the oscillation control circuit 6 is at an H (high) level. It should
 be noted that the numerical values described herein (e.g., those shown in
 parentheses) are merely reference values, and the present invention is not
 limited to the exemplary values.
 The oscillation control circuit 6 includes a pulse oscillation circuit 7
 that outputs the control pulse signal Vb (e.g., a square pulse signal with
 a frequency of 66 Hz and a duty ratio of 50%). The oscillation control
 circuit 6 also includes a constant-voltage circuit 8 which receives power
 from a commercial AC power supply (e.g., AC 100 V) via a power supply
 switch SW and a current fuse F. The constant-voltage circuit 8 outputs two
 types of constant voltages, i. e., high and low (Va.sub.1 =30 V and
 Va.sub.2 =20 V), to the ultrasonic oscillation circuit 4.
 The detection circuit 5 includes a parallel circuit including a detection
 resistance Rs and a capacitor C1 connected in parallel (via a diode D1) to
 both ends of a resistance R1. The parallel circuit is inserted into the
 current path from the ultrasonic oscillation circuit 4 to the ultrasonic
 vibrator 2. Accordingly, the current Ic (e.g., 2 Amperes peak-to-peak --2A
 p-p) flowing to the ultrasonic vibrator 2 is converted into a voltage Vd
 (e.g., 2 V p-p), and the envelope is detected. The voltage Vd is compared
 with a reference voltage Vref by a comparator CP, and the result of this
 comparison (an H level or L level signal Ve) is output to the
 constant-voltage circuit 8 of the oscillation control circuit 6.
 Specifically, when the application member 1 is not in contact with the
 skin, the vibration amplitude of the application member 1 reaches a
 maximum, and the electrical impedance of the ultrasonic vibrator 2 is
 reduced (e.g., to 20 ohms). Conversely, when the application member 1 is
 in contact with the skin, the vibration amplitude of the application
 member 1 is reduced, so that the impedance of the ultrasonic vibrator 2
 increases (e.g., to 40 ohms). Accordingly, the contacting state (contact
 or non-contact) of the application member 1 with the skin can be detected
 according to the variation in the voltage value obtained by the envelope
 detection. Furthermore, the output of the comparator CP (which is pulled
 up by a resistance R2) is fed back to the reference voltage Vref, so that
 hysteresis is generated with respect to the reference voltage Vref (as
 described in detail later).
 FIG. 3 is a timing chart describing the operation of the first embodiment.
 Prior to initiation of use (a first operation), the application member 1
 is not in contact with the skin (e.g., for a time T1 as shown in FIG. 3).
 When the power supply switch SW is closest so that the supply of power
 from the commercial AC power supply is initiated, a control pulse signal
 Vb (e.g., frequency: 66 Hz, duty ratio: 50%) is output from the pulse
 oscillation circuit 7 of the oscillation control circuit 6. Furthermore, a
 low-level constant voltage Va.sub.2 is output to the ultrasonic
 oscillation circuit 4 from the constant-voltage circuit 8.
 When the control pulse signal Vb and constant voltage Va.sub.2 are thus
 input into the ultrasonic oscillation circuit 4, the ultrasonic
 oscillation circuit 4 outputs an oscillating voltage Vc with an
 intermittent burst waveform (e.g., oscillation frequency: 1 MHz,
 oscillation amplitude: 40 V p-p) in synchronization with the H level
 periods of the control pulse signal Vb to the ultrasonic vibrator 2.
 The ultrasonic vibrator 2 receives the oscillating voltage Vc from the
 ultrasonic oscillation circuit 4 and vibrates, and the vibration is
 propagated to the application member 1. At this time, since the
 application member 1 is not in contact with the skin, the vibration
 amplitude of the application member 1 is at a maximum. Accordingly, the
 electrical impedance of the ultrasonic vibrator 2 is reduced (e.g., to 20
 ohms). As a result, the value of the current Ic that flows to the
 ultrasonic vibrator 2 also increases (e.g., 2 A p-p).
 In the detection circuit 5, the current Ic that flows to the ultrasonic
 vibrator 2 is converted into a voltage (e.g., 2 V p-p), and a voltage Vd
 obtained by the envelope detection is input into the comparator CP. In
 this case, the voltage Vd input into the comparator CP is substantially
 close to the peak value (e.g., 1 V), and is therefore higher than the
 reference voltage Vref (e.g., set at 0.9 V), i. e., Vd&gt;Vref. Accordingly,
 it is determined that the application member 1 is not in contact with the
 skin, so that the detection voltage Ve output by the detection circuit 5
 is set to the H level.
 Furthermore, since the detection voltage Ve of the detection circuit 5 is
 at the H level, output of the low-level constant voltage Va.sub.2
 continues from the constant-voltage circuit 8 of the oscillation control
 circuit 6, so that the level of the ultrasound that is emitted from the
 ultrasonic vibrator 2 via the application member 1 is also kept at the
 lower level (e.g., 40 V p-p).
 At initiation of use (a second operation), the application member is
 brought into contact with the skin (for a time T2 as shown in FIG. 3). For
 example, if the user holds the probe 3 and brings the application member 1
 in contact with the skin, the vibration amplitude of the application
 member 1 is reduced; accordingly, the electrical impedance of the
 ultrasonic vibrator 2 increases (e.g., to 40 ohms), so that the current Ic
 flowing to the ultrasonic vibrator 2 drops (e.g., to 1 A p-p). As a
 result, the voltage Vd obtained by the envelope detection of the current
 Ic also drops (e.g., to 0.5 V) below the reference voltage Vref, i.e.,
 Vd&lt;Vref. Accordingly, it is determined that the application member 1 is in
 contact with the skin, and the detection voltage Ve output from the
 comparator CP changes to an L level voltage.
 In the constant-voltage circuit 8, when the detection voltage Ve input from
 the detection circuit 5 changes to the L-level voltage, a high-level
 standard voltage Va.sub.1 (e.g. 30 V) is output to the ultrasonic
 oscillation circuit 4. As a result, the amplitude of the oscillating
 voltage Vc output to the ultrasonic vibrator 2 from the ultrasonic
 oscillation circuit 4 increases (e.g., to 60 V p-p). Accordingly, the
 current Ic flowing to the ultrasonic vibrator 2 also increases (e.g., to
 1.5 A p-p), so that the level of the ultrasound applied to the skin via
 the application member 1 is increased (compared to the level during the
 "non-contact" state).
 At the same time, the output of the comparator CP changes to the L level,
 so that the reference voltage Vref increases as a result of hysteresis
 (e.g., from 0.9 V to 1.4 V). Moreover, since a high-level voltage Va.sub.1
 is output from the constant-voltage circuit 8, the voltage Vd obtained by
 the envelope detection increases (e.g., to 0.75 V). However, since the
 reference voltage Vref is increased as described above, the application
 member 1 is judged to be in a contacting state of "contact" (even if there
 is some fluctuation), so that the output of the comparator CP is
 maintained at the L level.
 Following completion of use (a third operation), the application member is
 removed from the skin (for a time T3, as shown in FIG. 3). When the user
 removes the application member 1 of the probe 3 from the skin, the
 electrical impedance of the ultrasonic vibrator 2 again decreases (e.g.,
 to 20 ohms). At this time, the amplitude of the oscillation voltage Vc
 output to the ultrasonic vibrator 2 from the ultrasonic oscillation
 circuit 4 is substantially at the maximum (e.g., 60 V p-p), so that the
 current Ic flowing F to the ultrasonic vibrator 2 increases (e.g., to 3 A
 p-p). The current Ic is converted to a voltage (e.g., 3 V p-p).
 Accordingly, the voltage Vd (e.g., which becomes 1.5 V because of the
 capacitor C1) increases beyond the reference voltage Vref (e.g., 1.4 V).
 As a result, it is judged that the application member 1 is not in contact
 with the skin, and the detection voltage Ve that is output from the
 comparator CP changes to an H level voltage.
 When an H-level detection voltage Ve is input as a result of a judgement of
 non-contact by the detection circuit 5, a low-level constant voltage
 Va.sub.2 (20 V p-p) is output to the ultrasonic oscillation circuit 4 from
 the constant-voltage circuit 8 of the oscillation control circuit 6. At
 the same time, the output of the comparator CP changes from H level to L
 level, so that the reference voltage Vref changes from 1.4 V to 0.9 V.
 In the first embodiment, as described above, the detection circuit 5
 detects the contact or non-contact of the application member 1 of the
 probe 3 with the skin. Accordingly, when the contacting state of the
 application member 1 with the skin is detected as "non-contact" by the
 detection circuit 5, unnecessary rise in the temperature of the
 application member 1 is suppressed by using the oscillation control
 circuit 6 to lower the level of the ultrasound emitted from the ultrasonic
 vibrator 2 via the application member 1. Furthermore, when the contacting
 state of the application member 1 with the skin is detected as "contact"
 by the detection circuit 5, the desired cosmetic treatment effect is
 obtained by using the oscillation control circuit 6 to increase the level
 of the ultrasound emitted from the ultrasonic vibrator 2 via the
 application member 1.
 FIG. 4 shows a block diagram of the second embodiment of the present
 invention. As is shown in FIG. 4, the basic construction of the second
 embodiment is substantially similar to that of the first embodiment.
 Accordingly, elements which are common to both embodiments are labeled
 with the same symbols, and a description of such elements is omitted. Only
 those elements of the second embodiment different from those of the first
 embodiment are described.
 In the first embodiment, the contacting state of the application member 1
 with the skin varies frequently during use; accordingly, after a
 contacting state of "non-contact" has been detected by the detection
 circuit 5 and the level of the ultrasound has been lowered, even if the
 contacting state should again be detected as "contact" by the detection
 circuit 5 (and the level of the ultrasound returned to the original
 level), a time delay may be generated, so that the ultrasound level
 remains at a low level, preventing the desired cosmetic treatment effect.
 Accordingly, the second embodiment includes a delay timer 9 that delays
 the input of the detection voltage Ve output by the detection circuit 5
 into the constant-voltage circuit 8 of the oscillation control circuit 6
 by a predetermined delay time Td, so that the level of the ultrasound
 emitted from the ultrasonic vibrator 2 via the application member 1 is
 lowered only in the case of non-contact for a time exceeding the
 abovementioned delay time Td.
 The delay timer 9 is triggered by an H-level detection voltage Ve input
 from the detection circuit 5, and begins to count the predetermined delay
 time Td (e.g., 3 seconds in the case of the second embodiment). When an
 L-level detection voltage Ve is output to the constant-voltage circuit 8
 during the counting of the delay time Td, an H-level detection voltage Ve
 is output following the completion of the counting of the delay time Td,
 and the detection voltage Ve input from the detection circuit 5 changes to
 an L level during the counting of the delay time Td. Accordingly, the
 count is thus interrupted and reset.
 The timing chart of FIG. 5 describes the operation of the second
 embodiment. The operations prior to the initiation of use (e.g., the time
 T1 during which the application member 1 is not in contact with the skin)
 and when use is initiated (e.g., the time T2 during which the application
 member is in contact with the skin) are similar to the first embodiment.
 Accordingly, description of the operations prior to initiation of use and
 when use is initiated is omitted.
 In the second embodiment, during use, the application member 1 may be
 temporarily removed from the skin (for a time T3 as shown in FIG. 5), for
 example, in order to move the application member from the cheek to the
 jaw. When the application member 1 is removed from the skin, the detection
 circuit 5 detects a contacting state of "non-contact", so that an H-level
 detection voltage Ve is input into the delay timer 9, When the H-level
 detection voltage Ve is thus input, the delay timer 9 begins to count the
 delay time Td. Accordingly, an L-level detection voltage Ve that indicates
 a contacting state of "contact" continues to be output from the delay
 timer 9 to the constant-voltage circuit 8 of the oscillation control
 circuit 6 during this count. As a result, a high-level standard voltage
 Va.sub.1 is output to the ultrasonic oscillation circuit 4 from the
 constant-voltage circuit 8, so that the level (amplitude) of the
 ultrasound emitted via the application member 1 is also maintained at a
 high level.
 In this case, when the application member 1 contacts the skin during the
 counting of the delay time Td, an L level detection voltage Ve is input to
 the delay timer 9 from the detection circuit 5. When the L level detection
 voltage Ve is thus input during the counting of the delay time Td, the
 delay timer 9 resets the count, so that the count is interrupted.
 Consequently, a high-level standard voltage Va.sub.1 is output to the
 ultrasonic oscillation circuit 4 from the constant-voltage circuit 8, so
 that the level (amplitude) of the ultrasound that is emitted via the
 application member 1 is maintained at a high level. (i.e., as is).
 Conversely, when the application member 1 is removed from the skin for a
 time exceeding the delay time Td, the count of the delay timer 9
 completes. Consequently, an H level detection voltage Ve is output to the
 constant-voltage circuit 8. In the constant-voltage circuit 8, when the
 detection voltage Ve input from the detection circuit 5 via the delay
 timer 9 changes to the H-level voltage, a low-level constant voltage
 Va.sub.2 is output to the ultrasonic oscillation circuit 4. At the same
 time, the output of the comparator CP changes from the L level to the H
 level, so that the reference voltage Vref is decreased (e.g., changes from
 1.4 V to 0.9 V).
 In the second embodiment, as described above, a delay timer 9 is provided
 which delays (by a delay time Td) the output of an H-level detection
 voltage Ve to the oscillation control circuit 6 when the detection voltage
 Ve output by the detection circuit 5 changes from an L level ("contact")
 to an H level ("non-contact"). As a result, when a change from a
 contacting state of "contact" to one of "non-contact" is detected by the
 detection circuit 5, the level of the output from the ultrasonic
 oscillation circuit 4 to the ultrasonic vibrator 2 is lowered after the
 delay time Td has elapsed. That is, the level of the output from the
 ultrasonic oscillation circuit 4 to the ultrasonic vibrator 2 is lowered
 by the oscillation control circuit 6 to a level lower than that of the
 level of the output in a contacting state of "contact". Accordingly, since
 the level of the ultrasound that is emitted from the ultrasonic vibrator 2
 via the application member 1 is lowered only when the state of
 "non-contact" extends longer than the predetermined delay time Td, stable
 use is possible. That is, unnecessary increase or decrease of the
 ultrasound level is prevented, even in cases where the contacting state of
 the application member 1 with the skin varies frequently during use.
 FIG. 6 shows a block diagram of the third embodiment of the present
 invention. As shown in FIG. 6, the basic construction of the third
 embodiment is substantially similar to that of the first embodiment.
 Accordingly, elements which are common to both embodiments are labeled
 with the same symbols, and a description of such elements is omitted. Only
 those elements of the third embodiment different from those of the first
 embodiment are described.
 In the third embodiment, the ultrasonic cosmetic treatment device includes
 a display device 10 that displays (indicates) the contacting state
 (contact or non-contact) of the application member 1 of the probe 3 with
 the skin in accordance with the detection results obtained by the
 detection circuit 5. The display device 10 may be in the housing H
 separate from the housing of the probe 3. The device further includes a
 display delay timer 11 which delays (by a predetermined delay time
 Td.sub.2), the input into the display device 10 of the detection voltage
 Ve output by the detection circuit 5. The display device 10 and the
 display delay timer 11 together form a display for displaying the
 contacting state.
 The display device includes a contact display part 10a and a non-contact
 display part 10b (preferably including light-emitting elements such as
 light emitting diodes or the like). When the detection circuit 5 detects
 that the application member 1 is in contact with the skin, the contact
 display part 10a is lit, and the non-contact display part 10b is
 extinguished. Conversely, when the detection circuit 5 detects that the
 application member 1 is not in contact with the skin, the contact display
 part 10a is extinguished, and the non-contact display part 10b is lit. In
 this way, the user is informed of the contacting state (contact or
 non-contact) of the application member 1 with the skin.
 The display delay timer 11 is triggered by an H-level detection voltage Ve
 input from the detection circuit 5, and begins to count a predetermined
 delay time Td.sub.2 (e.g., 2 seconds in the case of the third embodiment).
 When an L-level detection voltage Ve is output to the display device 10
 during the counting of the delay time Td.sub.2, an H-level detection
 voltage Ve is output following the completion of the counting of the delay
 time Td.sub.2, and the detection voltage Ve input from the detection
 circuit 5 changes to the L level during the counting of the delay time
 Td.sub.2. Consequently, the count is interrupted and reset.
 The timing chart of FIG. 7 describes the operation of the third embodiment.
 Prior to initiation of use (a first operation), the application member 1
 is not in contact with the skin (during a time T1 as shown in FIG. 7). The
 detection circuit 5 detects a contacting state of "non-contact", and
 inputs an H-level detection voltage Ve into the display delay timer 11.
 The display delay timer 11 outputs the H-level detection voltage Ve ("as
 is") to the display device 10, so that the contact display part 10a of the
 display device 10 is switched off (extinguished) and the non-contact
 display part 10b is switched on (lit).
 At initiation of use (a second operation), the application member is in
 contact with the skin (during a time T2, as shown in FIG. 7).
 Consequently, the detection circuit 5 detects a contacting state of
 "contact" and inputs an L-level detection voltage Ve to the display delay
 timer 11. When the level of the detection voltage Ve changes from the H
 level to the L level, the display delay timer 11 immediately outputs an
 L-level signal to the display device 10. Accordingly, the contact display
 part 10a of the display device 10 is switched on (lit), and the
 non-contact display part 10b is switched off (extinguished).
 During use (a third operation), the application member 1 may be temporarily
 removed from the skin, for example, in order to move the application
 member from the cheek to the jaw (during a time T3, as shown in FIG. 7).
 When the application member 1 is removed from the skin, the detection
 circuit 5 detects a contacting state of "non-contact", and inputs an H
 level detection voltage Ve to the display delay timer 11. When the level
 of the detection voltage Ve changes from the L level to the H level, the
 display delay timer 11 begins to count the delay time Td.sub.2, and
 continues to output the L level detection voltage Ve (indicating a
 contacting state of "contact") to the display device 10 during the count.
 As a result, the contact display part 10a remains on (lit), and the
 non-contact display part 10b remains off (extinguished).
 If the application member 1 is brought into contact with the skin during
 the counting of the delay time Td.sub.2, an L level detection voltage Ve
 is input to the display delay timer 11 from the detection circuit 5. When
 the L-level detection voltage Ve is thus input during the counting of the
 delay time Td.sub.2, the display delay timer 11 resets the count, so that
 the count is interrupted. Accordingly, the contact display part 10a of the
 display device 10 remains on (lit), and the non-contact display part 10b
 remains off (extinguished).
 Conversely, if the application member 1 is removed from the skin for a time
 exceeding the delay time Td.sub.2, the count of the display delay timer 11
 completes, and an H-level detection voltage Ve is output to the display
 device 10. In the display device 10, when the detection voltage Ve input
 from the detection circuit 5 via the display delay timer 11 changes to the
 H level, the contact display part 10a is switched off (extinguished), and
 the non-contact display part 10b is switched on (lit).
 In the third embodiment, as described above, the device includes a display
 device 10 that displays the contacting state (contact or non-contact) of
 the application member 1 of the probe 3 with the skin in accordance with
 the detection results obtained by the detection circuit 5. The third
 embodiment further includes a display delay timer 11 that delays the
 output of the detection voltage Ve to the display device 10 by counting a
 predetermined delay time Td.sub.2 when a change from a contacting state of
 "contact" to one of "non-contact" is detected by the detection circuit 5.
 Accordingly, the user is informed of the contact or non-contact of the
 application member 1 with the skin by the display device 10.
 Furthermore, since the display device 10 is switched from a contact display
 to a non-contact display only when the non-contact state extends longer
 than the predetermined delay time Td.sub.2, a stable display is achieved.
 That is, unnecessary switching between a contact display and non-contact
 display is prevented, even in cases where the contacting state of the
 application member 1 with the skin changes frequently during use.
 FIG. 8 shows a block diagram of the fourth embodiment of the present
 invention. As shown in FIG. 8, the basic construction of the fourth
 embodiment is substantially similar to that of the first embodiment.
 Accordingly, elements which are common to both embodiments are labeled
 with the same symbols, and a description of such elements is omitted. Only
 those elements of the fourth embodiment different from those of the first
 embodiment are described.
 In the fourth embodiment, the ultrasonic cosmetic application device
 includes a pulse-passing circuit 12 that stops the oscillating operation
 of the ultrasonic oscillation circuit 4 when abnormalities occur in the
 control pulse signal Vb output from the pulse oscillation circuit 7 of the
 oscillation control circuit 6. It should be noted that the ultrasonic
 oscillation circuit 4 outputs an oscillating voltage Vd with a
 predetermined frequency Vc only during periods when the control pulse
 signal Vb from the oscillation control circuit 6 is at an L level.
 The pulse-passing circuit 12 includes a transistor Q1 that is switched on
 and off by the control pulse signal Vb output from the pulse oscillation
 circuit 7, and a parallel circuit including a resistance R3 and a diode D2
 parallel-connected to a collector resistance Rc of the transistor Q1 via a
 capacitor C2. Further, the pulse-passing circuit 12 includes a Schmidt
 input NOT gate 13 that inputs the voltage across the ends of the
 resistance R3. The pulse-passing circuit allows only pulse signals with a
 predetermined length to pass.
 When an L level control pulse signal Vb is input into the base of the
 transistor Q1, the transistor Q1 is switched on, so that the collector of
 the transistor Q1 assumes an H level. The L level control pulse signal Vb
 is thereby input into the NOT gate 13 via the capacitor C2. Since the NOT
 gate 13 inverts the input signal and outputs the resulting inverted
 signal, an L level signal is ultimately output from the pulse-passing
 circuit 12. On the other hand, when the control pulse signal Vb is an H
 level signal, the transistor Q1 is switched off. In this case, the
 collector of the transistor Q1 is pulled down by the resistance Rc, and
 thereby assumes the L level. Since the L level signal is input into the
 NOT gate 13 via the capacitor C2, the output from the pulse-passing
 circuit 12 is an H-level output. Thus, under ordinary conditions, the
 pulse-passing circuit 12 outputs (passes) a pulse signal that is the same
 as the control pulse signal Vb (input from the pulse oscillation circuit
 7) to the ultrasonic oscillation circuit 4.
 If the oscillation control circuit 6 (previously described in detail) is,
 for example, constructed from an integrated (e.g., one-chip)
 microcomputer, and control is lost due to noise, etc., the control pulse
 signal Vb may become (abnormally) fixed at the H level or L level.
 However, with the pulse-passing circuit 12 of the fourth embodiment, if the
 control pulse signal Vb becomes (abnormally) fixed at the H level, the
 transistor Q1 remains off, so that the input to the NOT gate 13 is fixed
 at the L level. Accordingly, the output of the pulse-passing circuit 12 is
 also fixed at the H level.
 Conversely, if the control pulse signal Vb becomes (abnormally) fixed at
 the L level, the transistor Q1 remains on, and an H level signal is input
 into the NOT gate 13 via the capacitor C2. However, the input level of the
 NOT gate 13 drops to the L level after a predetermined time Tn has
 elapsed, because of the action of the resistance R3. As a result, if the
 control pulse signal Vb is at the L level for a time exceeding the
 predetermined time Tn, the output level of the pulse-passing circuit 12
 switches from L to H, so that the passage of the control pulse signal Vb
 to the ultrasonic oscillation circuit 4 is blocked. The abovementioned
 predetermined time Tn is determined by the setting of the constants of the
 resistance R3 and capacitor C2, and the input threshold voltage of the NOT
 gate 13. In the present embodiment, the predetermined time Tn is set at a
 time (e.g., 15 ms) sufficiently longer than the pulse width of the control
 pulse signal Vb (e.g., 7.5 ms) that the normal control pulse signal Vb is
 passed through.
 The timing chart of FIG. 9 describes the operation of the fourth
 embodiment. First, in cases where a normal control pulse signal Vb is
 output from the pulse oscillation circuit 7 of the oscillation control
 circuit 6, the pulse-passing circuit 12 passes the control pulse signal Vb
 as is, and outputs the control pulse signal Vb to the ultrasonic
 oscillation circuit 4. Then, when the control pulse signal Vb and the
 constant voltage Va.sub.2 from the constant-voltage circuit 8 are input
 into the ultrasonic oscillation circuit 4, the ultrasonic oscillation
 circuit 4 outputs an oscillating voltage Vc with an intermittent burst
 waveform (e.g., oscillation frequency: 1 MHz, oscillation amplitude: 20 V
 p-p) in synchronization with the L level periods of the control pulse
 signal Vb to the ultrasonic vibrator 2. The ultrasonic vibrator 2 receives
 the oscillating voltage Vc from the ultrasonic oscillation circuit 4 and
 vibrates, and the vibration is propagated to the application member 1.
 However, if the control pulse signal Vb becomes (abnormally) fixed at the H
 level, the output of the pulse-passing circuit 12 is also fixed at the H
 level. Accordingly, the output of the oscillating voltage Vc from the
 ultrasonic oscillation circuit 4 is stopped, and the vibration of the
 ultrasonic vibrator 2 stops.
 Conversely, if the control pulse signal Vb becomes (abnormally) fixed at
 the L level, an L-level control pulse signal Vb passes through the
 pulse-passing circuit 12, and is input into the ultrasonic oscillation
 circuit 4 until the predetermined time Tn has elapsed. Accordingly, the
 output of the oscillating voltage Vc from the ultrasonic oscillation
 circuit 4 continues. However, when the predetermined time Tn has elapsed,
 the pulse-passing circuit 2 blocks the L-level control pulse signal Vb, so
 that an H-level signal is output to the ultrasonic oscillation circuit 4.
 Accordingly, the output of the oscillating voltage Vc from the ultrasonic
 oscillation circuit 4 is stopped.
 Thus, in the fourth embodiment, if the control pulse signal Vb becomes
 (abnormally) fixed at the H level or fixed at the L level (I. e., in the
 case of a pulse length that--at least--exceeds the predetermined time Tn),
 the output of the oscillating voltage Vc from the ultrasonic oscillation
 circuit 4 is forcibly stopped. Consequently, the emission of ultrasound
 from the ultrasonic vibrator 2 is suppressed when abnormalities occur in
 the control pulse signal Vb, preventing the application of undesirable
 abnormal ultrasound to the user's skin.
 Thus, in the described embodiments, when the application member is not in
 contact with the skin, the level of the ultrasound that is emitted from
 the ultrasonic vibrator via the application member is lowered, so that
 unnecessary rise in the temperature of the application member which
 contacts the skin is suppressed.
 In the second embodiment, the level of the ultrasound that is emitted from
 the ultrasonic vibrator via the application member is lowered only in the
 case of non-contact for a period longer than a predetermined delay time.
 Accordingly, even if the contacting state of the application member with
 the skin varies frequently during use, stable use is possible. That is,
 unnecessary increase or decrease in the level of the ultrasound is
 prevented.
 In the third embodiment, the user is informed by the display of the contact
 or non-contact of the application member with the skin. Furthermore, since
 the display may switch from a contact display to a non-contact display
 only in the case of non-contact for a period exceeding a predetermined
 delay time, a stable display is possible. That is, unnecessary switching
 between the contact display and non-contact display is prevented, even in
 cases where the contacting state of the application member with the skin
 varies frequently during use.
 In the fourth embodiment, in cases where abnormalities occur in the control
 pulse signal, no ultrasound is emitted from the ultrasonic vibrator, so
 that the application of undesirable abnormal ultrasound to the skin can be
 prevented.
 Although the above description sets forth particular embodiments of the
 present invention, modifications of the invention will be readily apparent
 to those skilled in the art, and it is intended that the scope of the
 invention be determined solely by the appended claims.
 The present disclosure relates to subject matter contained in Japanese
 Patent Application No. HEI 9-216771, filed on Aug. 11, 1997, which is
 expressly incorporated herein by reference in its entirety.