hair iron

Abstract

To provide a hair iron capable of arranging a hair style excellently without damaging hair.SOLUTION: A hair iron includes an arm part 13 extending from a base end part 12. The arm part 13 has a plate 40 which is long in the extending direction, and an elastic member 41 for supporting the reverse side of the plate 40. The elastic member 41 has nonlinear elasticity in which compression is easier when a load from the front side to the reverse side of the plate 40 is small than the case of being large.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a hair iron. [Background technology]

[0002] Hair irons used for styling hairstyles have been known. For example, the hair iron described in Patent Document 1 below has a pair of iron blades that are connected so as to be able to open and close. A user places their hair between the pair of iron blades, applies heat to the hair, and styles the hair. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-150999 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for the above-mentioned hair irons to be able to arrange hairstyles well without damaging the hair.

[0005] The present invention was developed in light of the above circumstances, and its object is to provide a hair iron that allows for good hairstyle arrangement without damaging the hair. [Means for solving the problem]

[0006] The hair iron of the present invention has an arm portion extending from a base end, and the arm portion has a plate that is long in the extension direction and an elastic member that supports the back side of the plate, and the elastic member has nonlinear elasticity that makes it easier to compress when the load from the front side to the back side of the plate is small than when it is large. [Effects of the Invention]

[0007] According to the present invention, the plates are displaced with a small force, making it easy to bring the plates into uniform contact with the hair. Therefore, the plates do not need to be pressed strongly against the hair, and the hairstyle can be arranged well without damaging the hair. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a hair iron according to an embodiment of the present invention; [Figure 2] A longitudinal cross-sectional view showing the hair iron in an open state [Figure 3] Partially enlarged perspective view showing the vicinity of the switch [Figure 4] An enlarged longitudinal cross-sectional view showing a part of the base end portion in a locked state. [Figure 5] FIG. 10 is an enlarged cross-sectional plan view showing a portion of the base end portion when the locking member is placed in the lock position. [Figure 6] FIG. 10 is an enlarged cross-sectional view showing a portion of the base end portion when the locking member is placed in the unlocked position. [Figure 7] FIG. 10 is a partially cutaway perspective view showing the locking portion in a locked state. [Figure 8] FIG. 10 is a partially cutaway perspective view showing the locking portion in an unlocked state. [Figure 9] A longitudinal cross-sectional view showing the clamping portion of the upper arm portion. [Figure 10] A plan view of the clamping portion of the upper arm as seen from below. [Figure 11] FIG. 10 is an exploded perspective view showing the clamping portion of the upper arm portion. [Figure 12] Flowchart showing the process when a power supply is connected to a hair iron [Figure 13] Table showing the configuration of a conical coil spring of a comparative example [Figure 14] FIG. 10 is a diagram showing the configuration of a conical coil spring of a comparative example. [Figure 15] Table showing the calculation results of the load and deflection of the conical coil spring of the comparative example [Figure 16] Graph showing the load-deflection curve of a conical coil spring of a comparative example DETAILED DESCRIPTION OF THE INVENTION

[0009] A preferred embodiment of the present invention is shown below.

[0010] In the hair iron of the present invention, the elastic member may support the plate at two or more points in the extending direction. With this configuration, the entire plate is supported in a balanced manner, making it easier for the entire plate to come into even contact with hair.

[0011] In the hair iron of the present invention, the elastic member may be a conical coil spring.

[0012] <Example> An embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 16. The hair iron 10 in this embodiment is used to arrange hairstyles. The hair iron 10 is a straightening iron, and as shown in FIG. 1, has a pair of arms 13A, 13B connected at a base end 12. The hair iron 10 arranges hairstyles by opening the pair of arms 13A, 13B, clamping hair therebetween, and applying heat to the hair. When the hair iron 10 is not in use, the pair of arms 13A, 13B are closed.

[0013] Hereinafter, the state in which the pair of arms 13A, 13B of the hair iron 10 are open will be referred to as the open state, and the state in which the pair of arms 13A, 13B are closed will be referred to as the closed state. In describing each component, the positive side of the Y axis in FIG. 1 (the side where the display unit 14 is provided) will be referred to as the upper side, the negative side of the Y axis in FIG. 1 will be referred to as the lower side, the positive side of the X axis (the tip side of the arms 13A, 13B) will be referred to as the front side, and the negative side of the X axis (the side where the base end 12 is provided) will be referred to as the rear side. The X axis indicates the front-to-rear direction or length direction, the Y axis indicates the up-down direction or thickness direction, and the Z axis indicates the left-to-right direction or width direction. In describing each arm 13A, 13B, the opposing sides of the pair of arms 13A, 13B will be referred to as the inner side or front side, and the sides opposite the opposing sides will be referred to as the outer side or back side.

[0014] The display unit 14 is provided on the outer surface of the upper arm portion 13A. The display unit 14 has, for example, an LED. The display unit 14 indicates whether the power is on or off, the set temperature, the charging state, etc.

[0015] The hair iron 10 includes a clamping portion 15 that clamps hair and a gripping portion 16 that is held by the user. The clamping portion 15 is the front portion of the hair iron 10. The gripping portion 16 is the rear portion of the hair iron 10. In the closed state, the length, width, and thickness of the clamping portion 15 are smaller than the length, width, and thickness of the gripping portion 16.

[0016] The hair iron 10 includes a cap case 17. The cap case 17 is placed over the clamping portion 15 in the closed state from the front.

[0017] The hair iron 10 is provided with comb-shaped portions 18. The comb-shaped portions 18 are provided on both the left and right sides of the clamping portion 15. The comb-shaped portions 18 are formed along both the left and right edges of the housing 24 (described later) over approximately the entire length of the clamping portion 15 (see FIG. 10). The comb-shaped portions 18 have a plurality of protrusions 19 arranged in the front-to-rear direction. Each protrusion 19 has a triangular shape with a pointed protruding end and is arranged at equal intervals. By providing the comb-shaped portions 18, the surface area of ​​the housing 24 can be increased, allowing for efficient heat dissipation and making it easier to reduce the temperature of the housing 24.

[0018] The hair iron 10 has a socket 22 for a USB cable 21. The socket 22 is compatible with USB Type-C. The socket 22 is provided at the base end 12 of the upper arm portion 13A and opens at the rear side. The hair iron 10 is connected to a power supply device (not shown) via the USB cable 21. The power supply device used can be one that complies with the USB PD (Power Delivery) standard.

[0019] As shown in Fig. 2, the pair of arms 13A, 13B can be freely moved between an open state and a closed state around a hinge 23 provided at the base end 12. Fig. 2 shows the hair iron 10 in the open state. Each of the pair of arms 13A, 13B extends linearly forward from the base end 12.

[0020] Each arm 13A, 13B has a housing 24 that is long in the front-rear direction. The components that make up the hair iron 10 are accommodated inside the housing 24. The cross section of the housing 24 is curved in an arc as shown in FIG. 7. The left and right edges of the housing 24 are located closer to the front than the center of the housing 24 in the left-right direction.

[0021] As shown in FIG. 2, the housing 24 has a battery housing 26 that houses a battery 25. The battery 25 is a rechargeable secondary battery such as a lithium-ion battery. The battery 25 is charged by connecting it to a power supply device via the USB cable 21. The hair iron 10 operates using power supplied from the battery 25.

[0022] Battery accommodating section 26 is provided in gripping section 16 of lower arm section 13B. The front side of battery accommodating section 26 is closed by battery cover 27. Battery cover 27 is detachable. By removing battery cover 27, battery 25 can be inserted or removed from battery accommodating section 26.

[0023] As shown in FIG. 3, the hair iron 10 is equipped with a switch 28 for turning the power on and off and for switching the set temperature of the heating element 44, which will be described later. The switch 28 is provided on the inner surface of the upper arm portion 13A. By providing the switch 28 on the inner surface of the upper arm portion 13A, it is possible to prevent accidental operation more effectively than if the switch 28 were provided on the outer surface. The switch 28 is slidable in the front-to-rear direction. The power-off position of the switch 28 is located behind the power-on position. FIG. 3 shows the switch 28 in the power-on position. When the cap case 17 is placed over the clamping portion 15, the switch 28 in the power-on position is pushed rearward by the pressing portion 17A provided on the cap case 17, moving to the power-off position.

[0024] 4, the base end portion 12 has a locking portion 30 that holds the pair of arm portions 13A, 13B in a closed state. The locking portion 30 has a first locking portion 31 provided on the upper side and a second locking portion 32 provided on the lower side. The first locking portion 31 and the second locking portion 32 come into contact with each other when the pair of arm portions 13A, 13B attempt to move from the closed state to the open state, thereby preventing further movement.

[0025] The first locking portion 31 protrudes downward from the housing 24 of the upper arm portion 13A.

[0026] The second locking portion 32 is provided on a locking member 33 held by the lower arm portion 13B. The locking member 33 swings left and right around a rotation shaft portion 33A between a locked position (see FIG. 5) and an unlocked position (see FIG. 6). In FIGS. 5 and 6, the first locking portion 31 is shown projected downward by an imaginary line.

[0027] As shown in FIG. 4, the locking member 33 includes a main body 34 and an operating portion 35. The main body 34 is plate-shaped. The second locking portion 32 protrudes upward from the main body 34. The main body 34 has a lock retaining portion 36 that maintains the position of the locking member 33. The lock retaining portion 36 is a recess formed on the back surface of the main body 34. The lock retaining portion 36 fits into a protrusion 37 provided on the lower arm portion 13B. The protrusion 37 is elastically displaced in the vertical direction by a spring member 38. The elastic force of the spring member 38 acts in a direction that moves the protrusion 37 upward.

[0028] A pair of lock retaining portions 36 are provided on the left and right sides. As shown in Fig. 5, the left lock retaining portion 36 fits into the protrusion 37, thereby retaining the lock member 33 in the locked position. As shown in Fig. 6, the right lock retaining portion 36 fits into the protrusion 37, thereby retaining the lock member 33 in the unlocked position.

[0029] The operating portion 35 is provided to protrude from the rear surface of the main body portion 34. The operating portion 35 protrudes rearward from the housing 24. By moving the operating portion 35 left and right, the position of the second locking portion 32 can be changed between a locked position and an unlocked position. At this time, the protrusion 37 is elastically displaced, providing the user with a clicking sensation.

[0030] As shown in Fig. 7, the contact surfaces 31A and 32A of the first locking portion 31 and the second locking portion 32 are inclined surfaces. When the contact surfaces 31A and 32A come into contact with each other in the vertical direction, a force is generated at the contact surfaces 31A and 32A that presses the second locking portion 32 in the unlocking direction (leftward in Fig. 7). When the force pressing the second locking portion 32 in the unlocking direction becomes greater than the force that displaces the protrusion 37 downward, the lock retaining portion 36 disengages from the protrusion 37, and the locking member 33 moves to the unlocked position (see Fig. 8).

[0031] The clamping portion 15 of the upper arm portion 13A and the clamping portion 15 of the lower arm portion 13B have substantially the same configuration. Here, the configuration of the clamping portion 15 of the upper arm portion 13A will be described, and a description of the configuration of the clamping portion 15 of the lower arm portion 13B will be omitted.

[0032] As shown in FIG. 9, each of the clamping portions 15 of the upper and lower arm portions 13A and 13B includes a plate 40 and an elastic member 41.

[0033] As shown in Fig. 10, the plate 40 has a generally rectangular plate shape that is long in the front-rear direction as a whole. The length of the surface of the plate 40 is 60 mm, and the width is 12 mm. As shown in Fig. 11, the plate 40 includes, in order from the front side, a surface plate 42, a carbon-containing thermally conductive layer 43, a heating element 44, a thermally conductive layer 45, a temperature sensor 46, an elastic sheet 47, an insulating sheet 48, a pressing member 49, a thermal fuse 51, and a bracket 52.

[0034] The surface plate 42 is a generally rectangular plate that is long in the front-to-rear direction. The surface plate 42 forms the contact surface that comes into contact with hair. The surface plate 42 has multiple holes 53 that penetrate from front to back. The holes 53 are arranged at equal intervals along the length of the surface plate 42. The front side of the surface plate 42 is covered with a low-friction sheet. The surface plate 42 has a peripheral wall 54 along its outer periphery. The peripheral wall 54 surrounds the outer periphery of the carbon-containing thermally conductive layer 43, the heating element 44, the thermally conductive layer 45, the elastic sheet 47, the insulating sheet 48, and the pressing member 49. The peripheral wall 54 has multiple protrusions 54A that protrude from the back side. The protrusions 54A guide the displacement of the plate 40 in the front-to-back direction relative to the housing 24.

[0035] The carbon-containing thermally conductive layer 43 is made of a graphite sheet. The carbon-containing thermally conductive layer 43 is rectangular and long in the front-to-rear direction, and is the same size as the back surface of the surface plate 42. The thickness of the carbon-containing thermally conductive layer 43 is uniform. The carbon-containing thermally conductive layer 43 is thin and flexible. Because the carbon-containing thermally conductive layer 43 is flexible, it is difficult to break even though it is thin. Because the carbon-containing thermally conductive layer 43 is thin, the space within the housing 24 can be used effectively. Because the carbon-containing thermally conductive layer 43 is made of a graphite sheet, the surface temperature of the surface plate 42 can be made uniform. This makes it less likely that uneven hair protein denaturation will occur due to localized temperature increases.

[0036] The carbon-containing thermally conductive layer 43 contains a large amount of carbon and has a higher thermal conductivity than metal. The carbon-containing thermally conductive layer 43 is sandwiched between the surface plate 42 and the heating element 44. By providing the carbon-containing thermally conductive layer 43, which has high thermal conductivity, between the surface plate 42 and the heating element 44, heat from the heating element 44 is quickly conducted to the surface plate 42. The heat from the heating element 44 is also quickly conducted in the planar direction of the carbon-containing thermally conductive layer 43, uniformly raising the temperature of the entire surface plate 42. The carbon-containing thermally conductive layer 43 emits far-infrared rays due to heat. The far-infrared rays are radiated to the hair through the holes 53 in the surface plate 42.

[0037] The heating element 44 is a flexible planar heating element. The heating element 44 is configured as a film heater in which a heater wire (not shown) is arranged on an insulating film. The heater wire is arranged over the entire surface of the film. The heating element 44 is a generally rectangular shape that is elongated in the front-to-rear direction. The heating element 44 is thin and lightweight. Electrodes are provided on both the front and rear ends of the heating element 44. The electrodes are fixed to the back surface of the pressing member 49 (see Figure 9).

[0038] The thermally conductive layer 45 is made of a metal foil (e.g., aluminum foil) with high thermal conductivity. The thermally conductive layer 45 is a generally rectangular shape that is long in the front-to-rear direction, and spreads thinly over the entire back surface of the heating element 44. The thermally conductive layer 45 is attached to the back surface of the heating element 44. The thermally conductive layer 45 efficiently transmits the temperature of the heating element 44 to the temperature sensor 46. The thermally conductive layer 45 and the carbon-containing thermally conductive layer 43 are generally the same size.

[0039] The temperature sensor 46 is an NTC thermistor or the like. The temperature sensor 46 detects the temperature of the heating element 44.

[0040] The elastic sheet 47 presses the temperature sensor 46 against the thermally conductive layer 45 (see FIG. 9). The elastic sheet 47 is a silicone sheet. The elastic sheet 47 keeps the components that make up the plate 40 in close contact with each other. The elastic sheet 47 has protrusions 55 that secure the insulating sheet 48.

[0041] The insulating sheet 48 is a mica sheet, and insulates the components that make up the plate 40.

[0042] The pressing member 49 is a generally rectangular plate that is long in the front-rear direction. The pressing member 49 is provided with a placement portion 56 in which the thermal fuse 51 is placed.

[0043] The bracket 52 is a generally rectangular plate that is long in the front-rear direction. The bracket 52 fixes the thermal fuse 51 between itself and the pressing member 49. Both front and rear ends of the bracket 52 have protruding pieces 52A that catch on the housing 24. This prevents the plate 40 from coming off.

[0044] The bracket 52 has positioning portions 57 that position the elastic member 41. The positioning portions 57 are provided to protrude from the rear surface of the bracket 52. The positioning portions 57 are provided at two locations, one at the front and one at the back of the bracket 52. The positioning portions 57 are located on both the front and rear sides of the thermal fuse 51 (see FIG. 9).

[0045] As shown in FIG. 9, the elastic member 41 supports the back side of the plate 40. The plate 40 is held floating above the housing 24 by the elastic member 41. The elastic member 41 is arranged in two locations, front and back. The elastic member 41 is tapered in side view. The elastic member 41 is circular in plan view (see FIG. 10). The elastic member 41 has nonlinear spring characteristics that make it easier to compress when the load from the front side to the back side is small than when it is large. In other words, the resistance to deformation of the elastic member 41 is constant at the beginning of compression, and increases as the compression amount increases from the middle of compression onwards. The maximum axial compression amount of the elastic member 41 is, for example, 1.5 mm. The large maximum compression amount of the elastic member 41 allows the plate 40 to be displaced greatly in the front-to-back direction.

[0046] One axial end of the elastic member 41 is a small diameter portion 41A, and the other axial end is a large diameter portion 41B. The diameter of the small diameter portion 41A is smaller than the diameter of the large diameter portion 41B. The small diameter portion 41A is disposed on the plate 40 side, and the large diameter portion 41B is disposed on the housing 24 side. The small diameter portion 41A fits into the outer periphery of a positioning portion 57 provided on the bracket 52.

[0047] The elastic member 41 is a conical coil spring. Conical coil springs have nonlinear elasticity, meaning that they are more easily compressed when the load from the front side to the back side is small than when it is large. Conical coil springs have the advantage that the coil parts do not interfere when compressed. The relationship between the load and deflection of a conical coil spring is nonlinear. Therefore, the greater the load applied to the conical coil spring, the smaller the amount of change in deflection of the conical coil spring.

[0048] The feel of using the hair iron 10 was compared using three conical coil springs (referred to as spring 1, spring 2, and spring 3) with different spring characteristics. The configurations of springs 1, 2, and 3 are as shown in Figures 13 and 14. The table in Figure 13 shows the material, modulus of transverse elasticity, wire diameter, minimum average diameter, maximum average diameter, number of turns, number of turns around the maximum diameter seat, number of turns around the minimum diameter seat, spring constant, pitch angle, and effective coil free height of each spring 1, 2, and 3.

[0049] The load of each spring 1, 2, 3 was calculated using the following formula 1. The deflection of each spring 1, 2, 3 was calculated using the following formula 2. Calculation formula 1: π×d 4 ×G×(α-d´ / (2×π×Rs)) / (32×Rs 2 ) Calculation formula 2: n / (R2-R1)×16×P×(Rs 4 -R1 4 ) / (G×d 4 )+π×α×(R2 2 -Rs 2 )-d´×(R2-Rs)) In formulas 1 and 2, d is wire diameter, G is modulus of transverse elasticity, α is pitch angle, d´ is contact pitch in the height direction, Rs is radius at which adhesion begins, R1 is minimum average radius, R2 is maximum average radius, and P is load.

[0050] The load and deflection of each spring 1, 2, and 3 were calculated using formulas 1 and 2. The calculation results and graphs are shown in Figures 15 and 16. According to the graph in Figure 16, the load that results in the same amount of deflection is the largest for spring 3 and the smallest for spring 1.

[0051] We asked several hairdressers to evaluate the feel of using the hair iron 10 using each of springs 1, 2, and 3 as the elastic member 41. The results are as follows: The feel of using the hair iron 10 using spring 3 as the elastic member 41 is better than the feel of using the hair iron 10 using springs 1 and 2 as the elastic member 41. The feel of using the hair iron 10 using spring 2 as the elastic member 41 is better than the feel of using the hair iron 10 using spring 1 as the elastic member 41. These evaluation results show that the more tactile feedback the plate 40 provides, the better the feel of using the hair iron 10. In other words, the plate 40 can be easily displaced with a weak force, and the tactile feedback of the plate 40 makes it easier for users to transfer the movement of their fingertips to the plate 40, resulting in a better feel of using the hair iron 10.

[0052] Next, an example of how to use the hair iron 10 of this embodiment will be described. The hair iron 10 is palm-sized and has small length and width dimensions. Because the plate 40 of the hair iron 10 is small, it is suitable for detailed styling of bangs, sideburns, etc.

[0053] Charging of the battery 25 begins when the USB cable 21 is inserted into the hair iron 10 and connected to a power supply. Completion of charging of the battery 25 is indicated on the display 14. Once charging of the battery 25 is complete, the USB cable 21 is unplugged. The hair iron 10 can be used cordlessly, making it suitable for use on the go.

[0054] The hair iron 10 operates not only on the battery 25 but also on power from a power supply device connected via a USB cable 21. FIG. 12 is a flowchart showing the process when the power supply device is connected to the hair iron 10 via the USB cable 21. This process starts when the power supply device is connected to the hair iron 10 via the USB cable 21 and the power to the hair iron 10 is turned on. When the process starts, the control circuit of the hair iron 10 determines whether the output of the power supply device is higher than a predetermined value (e.g., 36 W) (S10). If it is determined that the output of the power supply device is higher than the predetermined value (S10: YES), the control circuit of the hair iron 10 uses the power from the power supply device to increase the temperature of the heating element 44 (S11). On the other hand, if it is determined that the output of the power supply device is lower than the predetermined value (S10: NO), the control circuit of the hair iron 10 determines whether the battery 25 is sufficiently charged (S12). If it is determined that the battery 25 is not sufficiently charged (S12: NO), the control circuit of the hair iron 10 charges the battery 25 (S13). On the other hand, if it is determined that the battery 25 is sufficiently charged (S12: YES), the control circuit of the hair iron 10 uses power from the battery 25 to increase the temperature of the heating element 44 (S14). This flowchart ends when the power to the hair iron 10 is turned off.

[0055] The user removes the cap case 17 and moves the operating part 35 of the locking member 33 to the unlocked position, opening the hair iron 10. If the user tries to force the hair iron 10 to the open position without moving the operating part 35 to the unlocked position, the first locking part 31 and the second locking part 32 will come into contact with each other. This will allow the user to realize that the hair iron 10 is locked. If the user still tries to force the hair iron 10 to the open position, the contact force between the first locking part 31 and the second locking part 32 will increase, causing the locking member 33 to move to the unlocked position. This will prevent damage to the base end 12 of the hair iron 10.

[0056] After opening the hair iron 10, the user slides the switch 28 forward. The power is turned on, and the hair iron 10 operates using power from the battery 25 or a power supply. If the battery 25 is not fully charged, the display 14 will indicate this. The temperature of the heating element 44 will rise to the set temperature quickly (approximately 40 seconds) after the power is turned on.

[0057] The user places hair between the pair of arms 13A, 13B. Plate 40 displaces to fit closely to the hair. Because the stroke of plate 40 is large, the surface of plate 40 easily fits tightly to the hair. Furthermore, because plate 40 is easily displaced with a weak force, the user feels that the movement of their fingertips is easily transmitted to plate 40.

[0058] The heat from the heating element 44 is efficiently transferred to the surface plate 42 by the carbon-containing thermally conductive layer 43. The temperature of the entire surface of the plate 40 rises uniformly, and the plate 40 applies heat uniformly to the hair. Furthermore, far infrared rays are radiated from the carbon-containing thermally conductive layer 43 to the hair. This allows the hair to be quickly styled while retaining moisture. Furthermore, the protrusions 19 of the comb-shaped portion 18 improve the flow of the hair.

[0059] The heat from the heating element 44 is efficiently transferred to the surface plate 42 by the carbon-containing thermally conductive layer 43, so it is less likely to be trapped inside the housing 24. In addition, the heat inside the housing 24 is efficiently released to the outside by the comb-shaped portion 18. Therefore, the outer surface of the clamping portion 15 is prevented from becoming too hot, so the user can grip the outer surface of the clamping portion 15 to operate the hair iron 10.

[0060] After using the hair iron 10, the user slides the switch 28 to the power-off position to turn off the power. Then, the user closes the hair iron 10 and moves the operating part 35 of the locking member 33 to the locked position. This causes the first locking part 31 and the second locking part 32 to face each other vertically, keeping the hair iron 10 in the locked state. The user then puts on the cap case 17.

[0061] Even if the hair iron 10 is closed without moving the switch 28 to the power-off position, the switch 28 can be moved to the power-off position by covering it with the cap case 17. Therefore, the hair iron 10 can be prevented from being left in the power-on state.

[0062] Next, the operation and effects of the embodiment configured as described above will be described. The hair iron 10 of this embodiment includes arms 13A and 13B extending from the base end 12. The arms 13A and 13B each include a plate 40 that is long in the extension direction and an elastic member 41 that supports the back side of the plate 40. The elastic member 41 has nonlinear elasticity that makes it easier to compress when the load from the front side to the back side is small than when it is large. With this configuration, the plate 40 displaces with a small force, making it easier to bring the plate 40 into uniform contact with the hair. Therefore, the plate 40 does not need to be pressed strongly against the hair, allowing for good hairstyles without damaging the hair. Furthermore, because the plate 40 displaces with a small force, it can respond to delicate finger movements.

[0063] Furthermore, the elastic member 41 supports the plate 40 at two points in the extending direction. With this configuration, the entire plate 40 is supported in a balanced manner, which makes it easier for the entire plate 40 to come into uniform contact with the hair.

[0064] The elastic member 41 is a conical coil spring. This configuration allows for a sufficient amount of deflection in a small space, making it possible to achieve a compact design. In addition, it is easy to design the reaction force of the elastic member 41 to an appropriate value.

[0065] <Other Examples> The present invention is not limited to the embodiments described above and illustrated in the drawings, and the following embodiments are also included within the technical scope of the present invention. (1) In the above embodiment, the hair iron 10 is a straightening iron in which hair is sandwiched between a pair of arms 13A and 13B. However, the hair iron is not limited to this, and may be a curling iron having a cylindrical arm extending from a base end and a plate along the outer periphery of the arm, sandwiching hair between the arm and the plate. (2) In the above embodiment, the carbon-containing thermally conductive layer 43 is a flexible sheet. However, the carbon-containing thermally conductive layer is not limited to this, and may be a hard plate member or a layer to which a carbon material is sprayed. (3) In the above embodiment, the elastic member 41 is a conical coil spring. However, the elastic member is not limited to this, and may be any member that is easier to compress when the load from the front side to the back side is small than when it is large. For example, the elastic member may be a block-shaped member made of an elastic material, or may be a combination of multiple spring members. When combining multiple elastic members, members with different elastic forces may be combined. The elastic member may also be rubber, a leaf spring, a variable pitch coil spring, a tapered coil spring, etc. (4) In the above embodiment, the small diameter portion 41A of the conical coil spring is disposed on the plate 40 side, and the large diameter portion 41B is disposed on the housing 24 side. However, this is not limiting, and the small diameter portion of the conical coil spring may be disposed on the housing side, and the large diameter portion may be disposed on the plate side. (5) In the above embodiment, the elastic member 41 supports two points of the plate 40. However, the present invention is not limited to this, and the elastic member may support three or more points of the plate. (6) In the above embodiment, the battery 25 is rechargeable. However, the battery is not limited to this and may be, for example, a dry cell battery. (7) In the above embodiment, the dimensions of the plate 40 are exemplified. However, the dimensions of the plate are not limited to these and can be changed as appropriate. [Explanation of symbols]

[0066] 10...Hair iron 12...Proximal end 13...Arm section 40...Plate 41...Elastic member

Claims

1. An arm portion extending from the base end portion, The arm portion includes a plate that is long in the extension direction and an elastic member that supports a back side of the plate, The elastic member has nonlinear elasticity that makes it easier to compress when the load from the front side to the back side of the plate is small than when the load is large.

2. The hair iron according to claim 1 , wherein the elastic member supports the plate at two or more points in the extending direction.

3. The hair iron according to claim 1 or 2, wherein the elastic member is a conical coil spring.

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