JP2013088904A - Touch switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch switch of new structure capable of suppressing variation of a contact angle of a fingertip to an operation surface according to extension of a finger to raise detection accuracy in slide input for moving the fingertip to the tip side while bringing the fingertip into contact with the operation surface.SOLUTION: An operation surface 16 of a conductive member 14 which a finger 48 contacts includes a reference surface 40 which extends in the cross direction by using the tip side of the finger 48 as the front, the operation surface 16 includes a front curved surface 42 which extends while inclining upward from the reference surface 40 toward the front and whose inclination angle becomes larger toward the front side, and the front curved surface 42 has a curvature radius smaller than that of the reference surface 40.

Description

  The present invention relates to a touch switch for detecting an input at a fingertip of a user, and more particularly to a touch switch for detecting a sliding motion of a fingertip.

  Conventionally, the use of a touch switch has been studied as an input interface for operating a navigation system, an audio device, an air conditioner, and the like. This touch switch detects the presence or absence of a finger touching the operation surface, the contact position, a slide input for moving the fingertip while making contact with the operation surface, and the like. There are a detection type and a capacitance detection type for detecting based on a change in capacitance. This is shown in FIG. 2 of Japanese Patent Application Laid-Open No. 2006-7920 (Patent Document 1).

  By the way, as disclosed in Patent Document 1, the operation surface of the touch switch is generally flat in consideration of ease of manufacture.

  However, in such a flat-shaped touch switch, when the finger is gradually extended from a bent state and moved (slid) to the tip side while the fingertip is in contact with the operation surface, the angle of the finger with respect to the operation surface is increased. It gradually changes as the joint stretches. Thereby, the contact portion of the fingertip with the operation surface gradually moves to the proximal end side of the finger, and a shift may occur between the actual fingertip movement amount and the detected fingertip movement amount. The user may feel uncomfortable.

JP 2006-7920 A

  The present invention has been made in the background of the above-described circumstances, and the problem to be solved is the operation surface of the fingertip according to the extension of the finger during slide input in which the fingertip is moved to the tip side while touching the operation surface. It is an object of the present invention to provide a touch switch having a novel structure capable of suppressing a change in a contact angle with respect to the surface and improving detection accuracy.

  That is, according to a first aspect of the present invention, in the touch switch in which a voltage is applied to the conductive member and the contact movement of the finger on the conductive member is detected based on the energized state of the conductive member, The operation surface of the conductive member in contact with the finger has a reference surface extending in the front-rear direction with the tip side of the finger as the front, and the operation surface extends while tilting upward from the reference surface to the front. And a forward curved surface whose inclination angle increases toward the front side, and the forward curved surface has a smaller radius of curvature than the reference surface.

  According to the touch switch having the structure according to the first aspect as described above, when the fingertip moves forward on the operation surface and the proximal interphalangeal joint (second joint) of the finger is extended, It is located on the front curved surface of the operation surface. Thus, even when the interphalangeal joint is extended from the state in which the second joint is extended, and the fingertip is moved further forward while being in contact with the operation surface, the contact portion of the fingertip with respect to the operation surface is brought to the proximal side. It is possible to prevent the change, and the deviation between the actual fingertip contact movement amount and the fingertip contact movement amount detected by the sensor is reduced. As a result, the detection accuracy is improved, and a good operation feeling and an accurate operation of the device controlled by the touch switch are realized.

  Further, on the rear side continuous with the front curved surface, a reference surface having a larger radius of curvature than the front curved surface and extending in the front-rear direction is provided. When the second joint of the finger is bent, each joint By inputting while adjusting the bending, it is possible to sensuously realize an input at a substantially constant pressure, so that a good detection accuracy can be obtained. Moreover, by providing the reference surface, it becomes easier to ensure a large stroke in the front-rear direction when moving the fingertip in contact with the operation surface, which is curved and recessed with a constant curvature radius as a whole. It becomes possible to provide a touch switch more suitable for slide input.

  According to a second aspect of the present invention, in the touch switch described in the first aspect, the operation surface of the conductive member is inclined upward from the reference surface toward the rear side that is the base end side of the finger. A rear curved surface is provided that extends and has a larger inclination angle with respect to the reference surface toward the rear side.

  According to the second aspect, the fingertip is positioned on the rear curved surface in a state where the second joint of the finger is bent, so that the contact with the operation surface of the fingertip is stably maintained when the second joint is further bent. Thus, the contact movement of the fingertip with respect to the operation surface is stably detected.

  According to a third aspect of the present invention, in the touch switch described in the first or second aspect, a maximum value of an inclination angle of the front curved surface with respect to the reference surface: θ is 5 ° ≦ θ ≦ 60 °. The range is set.

  According to the third aspect, since the front curved surface is shaped along the movement of the fingertip due to the bending and stretching of the joint, the change of the contact portion with respect to the operation surface of the fingertip due to the bending and stretching of the joint is suppressed, and The change in pressure is reduced, and the detection accuracy of the slide input is improved.

  According to a fourth aspect of the present invention, in the touch switch described in any one of the first to third aspects, the operation surface of the conductive member is elongated in the front-rear direction.

  According to the 4th aspect, the amount of contact movement with respect to the operation surface of a fingertip can be ensured largely in the front-back direction. Therefore, it becomes easy for the user to grasp the input, and a good operational feeling can be obtained, and an improvement in the detection accuracy of the slide input can be realized.

  Note that the operation surface having the longitudinal direction as the longitudinal direction can be easily realized by having the reference surface as the operation surface. That is, by making the reference surface a longitudinal shape extending in the front-rear direction, the reference surface is elongated in the front-rear direction without affecting the shape of the front curved surface and the rear curved surface, which are desirably specified according to the trajectory of the fingertip movement. It is possible to realize the operation surface.

  According to the present invention, the operation surface includes the reference surface extending in the front-rear direction and the front curved surface continuously provided on the front side thereof, so that the fingertip moves forward. At the time of slide input, a sufficient stroke is ensured by the reference surface, and a change in the contact portion of the fingertip with respect to the operation surface is suppressed by the front curved surface, so that the amount of movement of the fingertip can be detected accurately.

The figure which shows the state by which the touch switch as the 1st Embodiment of this invention was provided in the door armrest of the motor vehicle. The figure explaining the touch switch shown by FIG. The top view which shows the electrically-conductive member of the touch switch shown by FIG. IV-IV sectional drawing of FIG. VV sectional drawing of FIG. The figure which expands and shows the principal part of the electrically-conductive member shown by FIG. The figure explaining the detection mechanism of the touch switch shown by FIG. FIG. 8 is an electric circuit diagram of the touch switch shown in FIG. 7. The figure explaining the use condition of the electrically-conductive member shown by FIG. The top view which shows the electrically-conductive member of the touch switch as the 2nd Embodiment of this invention. XI-XI sectional drawing of FIG. XII-XII sectional drawing of FIG. The figure which shows the principal part of the electrically-conductive member shown by FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 and 2 show a touch switch 10 as a first embodiment of the present invention. The touch switch 10 is disposed on the upper surface of an armrest 12 provided at the door portion of the automobile, and serves as an input interface for opening and closing the vehicle window. 2, 7, and 9, the touch switch 10 is illustrated to be relatively larger than the actual finger 48.

  More specifically, the touch switch 10 includes the conductive member 14 shown in FIGS. 3 to 5. The conductive member 14 is formed of a conductive material having a high electrical conductivity. In this embodiment, the conductive member 14 is formed of a conductive resin material obtained by mixing a conductive filler such as carbon black with a synthetic resin material. Then, the conductive member 14 is superposed and fixed on the upper surface of a base (not shown) having electrical insulation, for example. The conductive member 14 is made of a rubber-based conductive paint in which an organic solvent is added to a prepared rubber compound and carbon black as a conductive filler is mixed, and a printing solvent is further added. It may be formed by printing in a predetermined shape on the upper surface of the substrate by a method such as printing, flexographic printing, gravure printing, pad printing, or lithography. Furthermore, the conductive member 14 can be formed of a conductor such as a metal plate.

  In addition, the lower surface of the conductive member 14 is superimposed and fixed on the upper surface of a base (not shown), and an operation surface 16 is provided on the upper surface of the conductive member 14. The operation surface 16 has an oval shape in a plan view, has both ends in the left-right direction (up and down in FIG. 3) linearly extended in the front-rear direction, and both ends in the front-rear direction (left and right in FIG. 3). Is a curved shape convex toward the outside in the front-rear direction. Thereby, the operation surface 16 has a shape in which the front-rear direction is longer than the left-right direction in plan view. Then, contact and movement of a finger 48 described later on the operation surface 16 are detected based on a change in the energized state.

  A first DC power supply 20 is connected to one end of the conductive member 14, and a DC voltage is applied from the first DC power supply 20 to one end of the conductive member 14. On the other hand, a second DC power source 22 is connected to the other end of the conductive member 14, and a DC voltage is applied from the second DC power source 22 to the other end of the conductive member 14. The first and second DC power supplies 20 and 22 apply in-phase and same-potential voltages to the conductive member 14 from two locations. When the finger 48 described later is not in contact, the conductive member 14 is applied to the conductive member 14. No current flows.

  The first detection resistor 24 is connected to one end of the conductive member 14. The first detection resistor 24 is disposed on a connection path between the one end of the conductive member 14 and the first DC power supply 20 and is electrically connected to the conductive member 14 and the first DC power supply 20. ing. On the other hand, the second detection resistor 26 is connected to the other end of the conductive member 14. The second detection resistor 26 is disposed on a connection path between the other end of the conductive member 14 and the second DC power supply 22, and is electrically connected to the conductive member 14 and the second DC power supply 22. Has been. The first and second detection resistors 24 and 26 have the same resistance value (R ′).

  Further, a first voltmeter 28 for measuring the voltage applied to the first detection resistor 24 is provided, and a first voltage meter for measuring the voltage applied to the second detection resistor 26 is provided. Two voltmeters 30 are provided. Then, by confirming the energization state of the conductive member 14 based on the measured values of the first and second voltmeters 28 and 30, the presence or absence of contact with the conductive member 14 of the finger 48, which will be described later, and the contact position are detected. It has come to be.

  Further, the first and second voltmeters 28 and 30 are connected to the processing device 32 by wire or wirelessly. The processing device 32 includes a contact confirmation unit 34 that determines the presence or absence of contact of the finger 48 with the conductive member 14, which will be described later, based on the measurement results of the first and second voltmeters 28 and 30. The operation specifying means 36 for specifying the contact position and the change of the contact position (slide input) when contact with the 48 conductive members 14 is confirmed, and the control signal corresponding to the operation specified by the operation specifying means 36 are illustrated. Control signal output means 38 for outputting to a vehicle window opening and closing device.

  In the touch switch 10 having such a structure, the operation surface 16 of the conductive member 14 includes the reference surface 40. As shown in FIGS. 3 to 5, the reference surface 40 extends linearly in the front-rear direction and is curved and widened so as to be inclined outward in the left-right direction. It is made into the groove shape extended with a fixed cross section in the front-back direction. In the present embodiment, the reference surface 40 extends almost without inclining with respect to the horizontal plane in the front-rear direction. The reference surface 40 is a rectangle whose longitudinal direction is the front-rear direction of the vehicle in plan view. The reference plane 40 extending linearly in the front-rear direction means that the radius of curvature is infinite in the front-rear direction shown in FIG.

  Further, a front curved surface 42 is continuously provided on the front side (right side in FIG. 4) of the reference surface 40. The front curved surface 42 is an inclined surface that is gradually inclined upward toward the front side, and is an arcuate curved surface in which the relative inclination angle with respect to the reference surface 40 gradually increases toward the front side. In the present embodiment, a polygonal line is formed at the boundary between the reference surface 40 and the front curved surface 42, but the reference surface 40 and the front curved surface 42 may be smoothly continuous even if the boundary portion is formed by a curved surface. good.

  Furthermore, it is desirable that the maximum inclination angle relative to the reference surface 40 of the front curved surface 42 shown in FIG. 6: θ is set in a range of 5 ° ≦ θ ≦ 60 °. θ is set to 60 °. Further, it is desirable that the curvature radius r shown in FIG. 6 is set to a range of 10 mm ≦ r ≦ 3000 mm, and the front curved surface 42 is set to r = 30 mm in this embodiment. Further, the radius of curvature of the front curved surface 42 is smaller than the radius of curvature of the reference surface 40 set to infinity. In FIG. 6, the radius of curvature r of the front curved surface 42 is drawn smaller than the actual for ease of viewing.

  A rear curved surface 44 is continuously provided on the rear side (left side in FIG. 4) of the reference surface 40. The rear curved surface 44 is an inclined surface that gradually inclines upward toward the rear side, and is an arcuate curved surface that gradually increases in relative inclination angle with respect to the reference surface 40 as it goes rearward. In the present embodiment, the rear curved surface 44 is formed with substantially the same radius of curvature as the front curved surface 42 and a relative inclination angle with respect to the reference surface 40. Accordingly, the curved surface may have a shape different from that of the front curved surface 42.

  Further, the operation surface 16 is curved as a whole in the left-right direction (up-down direction in FIG. 3) and is inclined upward. As a result, the conductive member 14 is formed with an operation recess 46 having a longitudinally concave shape with the operation surface 16 as a bottom surface and opening on the upper surface. Although not particularly limited, the operation surface 16 according to the present embodiment has a maximum dimension of 25 mm in the longitudinal direction and a maximum dimension of 10 mm in the lateral direction. The size is such that slide input can be easily performed by bending and stretching the finger 48.

As shown in FIG. 7, when the finger 48 is inserted into the operation recess 46 of the conductive member 14 and the fingertip contacts the operation surface 16, the conductive member 14 is grounded through the human body including the finger 48. Currents I ₁ and I ₂ flow through the conductive member 14 and the first and second detection resistors 24 and 26.

When currents I ₁ and I ₂ flow through the first and second detection resistors 24 and 26, the first and second detection resistors 24 and 26 in the first and second voltmeters 28 and 30. The voltage values Vm ₁ and Vm ₂ corresponding to the current flowing through are measured. And the contact confirmation means 34 of the processing apparatus 32 is the finger 48 (with respect to the electrically-conductive member 14) when each measured value: Vm1, Vm2 of the _1st , _2nd voltmeters 28 and 30 is more than a predetermined numerical value. The contact of the detected conductor) is detected. In addition, the contact confirmation means 34 determines whether the measured value of the 1st, 2nd voltmeters 28 and 30 is more than a preset threshold value, for example, Comprising: A measured value is more than a threshold value. When it is determined that the contact of the finger 48 with the operation surface 16 of the conductive member 14 is detected.

Then, when contact of the finger 48 with the operation surface 16 of the conductive member 14 is detected, the operation specifying means 36 of the processing device 32 causes the finger 48 to move based on the measurement values of the first and second voltmeters 28 and 30. The contact position with respect to the operation surface 16 is specified. That is, as shown in FIG. 7, when the finger 48 comes into contact with the intermediate portion of the conductive member 14 whose overall resistance value is R, the conductive member 14 as the resistor has one end (in FIG. 7). , The left end) to the contact position of the finger 48 (the resistance value is R ₁ ), and the second resistor 52 from the other end (the right end in FIG. 7) to the contact position of the finger 48. (The resistance value is substantially R ₂ ). Resistance of the first resistor 50: the R _1, the resistance value of the second resistor 52: the ratio of R ₂ is, the distance from one end of the conductive member 14 to the contact position of the finger 48, the conductive Since the ratio of the distance from the other end of the member 14 to the contact position of the finger 48 is substantially the same, the contact position of the finger 48 with respect to the conductive member 14 is specified by determining the ratio of R ₁ and R _2. The FIG. 8 shows an electric circuit diagram of the state in which the finger 48 is in contact with the conductive member 14.

  Note that the measurement of the voltage value by the first and second voltmeters 28 and 30 is repeated at predetermined time intervals, and the operation specifying means 36 continuously detects the change in the contact position of the finger 48 with respect to the conductive member 14. doing. Thereby, when the tip part (fingertip) of the finger 48 is moved while being brought into contact with the surface (operation surface 16) of the conductive member 14, the displacement direction and the displacement amount of the finger 48 are specified.

  When the operation specifying unit 36 detects the contact position of the finger 48 or the movement while moving (slide input), the control signal output unit 38 of the processing device 32 detects the contact position of the finger 48 with respect to the operation surface 16 or the operation surface 16. A control signal corresponding to the amount of movement and the direction of movement while contacting the vehicle is output to the vehicle device. The device controlled by the operation of the touch switch 10 is not particularly limited, but in the present embodiment, for example, a vehicle window opening / closing device (not shown) is controlled, and the fingertip to the touch switch 10 is controlled. The opening / closing operation of the car window is executed in response to the slide input. In the present embodiment, by moving the finger 48 in the longitudinal direction of the operation recess 46 while making contact with the operation surface 16, the opening operation and the closing operation are performed according to the movement direction (left direction or right direction in FIG. 2). The operation is identified, and the opening / closing operation amount of the vehicle window is set according to the movement amount, and is output as a control signal from the control signal output means 38 to the opening / closing device of the vehicle window.

  At the time of such a slide input, the touch switch 10 is less likely to change the contact state of the fingertip with the operation surface 16 due to the bending and stretching of the finger 48, and the detection accuracy is improved.

  That is, as shown in FIG. 9A, when the proximal interphalangeal joint (second joint) of the finger 48 is bent, the fingertip is in contact with the reference plane 40, and each joint Slide input can be performed with a substantially constant contact pressure by moving the fingertip in the front-rear direction while adjusting the bending angle or the like.

  Next, when the second joint of the finger 48 is gradually extended, the fingertip reaches the front curved surface 42 as shown in FIGS. Then, in response to the arcuate movement of the fingertip after the bending of the joint becomes small, the operation surface 16 (front curved surface 42) is curved in an arc shape, so that the fingertip is separated from the operation surface 16. The contact movement of the fingertip with respect to the operation surface 16 is stably detected.

  On the other hand, when the joint of the finger 48 is bent more greatly from the state of FIG. 9A, the fingertip is displaced to the front side (rear side) of the user and reaches the rear curved surface 44. Yes. Then, in response to the arcuate movement of the fingertip after the bending of the joint becomes large, the operation surface 16 (rear curve surface 44) is curved in an arc shape, so that the fingertip is separated from the operation surface 16. The contact movement of the fingertip with respect to the operation surface 16 is stably detected.

  As described above, the operation surface 16 includes the reference surface 40, the front curved surface 42 that continues to the front side thereof, and the rear curved surface 44 that continues to the rear side. By adopting a shape that takes the movement trajectory into consideration, it is possible to ensure a large area on the operation surface 16 where input can be detected with sufficient accuracy when performing slide input in the front-rear direction. In particular, at the front end and the rear end of the operation surface 16, the fingertip is separated from the operation surface 16 and cannot be detected, or the contact portion of the fingertip with the operation surface 16 changes and the detection result differs from the actual movement of the fingertip. Therefore, detection with high accuracy can be realized stably over the entire operation surface 16.

  In addition, since the reference surface 40 extending in the front-rear direction is provided between the front curved surface 42 and the rear curved surface 44, a large stroke for sliding input in the front-rear direction is ensured. As a result, the amount of movement of the fingertip increases during slide input, making it easier for the user to feel the input and improving detection accuracy. In particular, in the plan view, the reference surface 40 has a longitudinal shape in the front-rear direction, and the operation surface 16 has a longitudinal shape in the front-rear direction. The input stroke at is efficiently secured.

  The maximum value of the relative inclination angle of the front curved surface 42 with respect to the reference surface 40: θ is 60 °, and is set in a range of 5 ° ≦ θ ≦ 60 °. Thereby, the change of the contact part with respect to the operation surface 16 of a fingertip can be suppressed effectively with respect to extension of the finger 48, and the fall of the detection accuracy by the change of a contact part is prevented.

  Further, the curvature radius r of the front curved surface 42 is set to 30 mm, and is set in a range of 10 mm ≦ r ≦ 3000 mm. Thereby, the contact state of the fingertip with respect to the operation surface 16 with respect to the extension of the finger 48 is stably maintained, and the input with a substantially constant pressure can be easily performed, so that the detection accuracy can be improved.

  Since the maximum value of the relative inclination angle of the rear curved surface 44 with respect to the reference surface 40 and the radius of curvature of the rear curved surface 44 are the same as those of the front curved surface 42, the same as the front curved surface 42. In addition, the detection accuracy is improved.

  10 to 12 show a conductive member 60 constituting a touch switch according to a second embodiment of the present invention. Similar to the conductive member 14 of the first embodiment, the conductive member 60 is formed of a conductive resin material obtained by mixing a conductive filler such as carbon black with a synthetic resin material. In the following description, members and parts that are substantially the same as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. Further, in the touch switch of the present embodiment, portions not shown in the drawing are substantially the same as the touch switch 10 of the first embodiment.

  In addition, an operation surface 62 is formed on the conductive member 60. The operation surface 62 is formed as a bottom surface of an operation recess 64 that opens to the upper surface of the conductive member 60, and includes a reference surface 66.

  The reference surface 66 is provided at an intermediate portion in the front-rear direction of the operation surface 62, and has an arcuate curved shape that is inclined upward in the front-rear direction as shown in FIG. Further, as shown in FIG. 12, the reference surface 66 has an arcuate curved shape that inclines upward in the left-right direction.

  A front curved surface 68 is provided on the front side of the reference surface 66. The front curved surface 68 is continuously provided so as to extend forward from the front end of the reference surface 66, and is inclined in an arc shape in which the inclination angle increases toward the front side while being inclined upward. The curved surface. Further, like the reference surface 66, the front curved surface 68 is curved so as to incline upward in the left-right direction.

  A rear curved surface 70 is provided on the rear side of the reference surface 66. The rear curved surface 70 is continuously provided so as to extend rearward from the rear end of the reference surface 66, is inclined upward, and the inclination angle increases toward the rear side. It is an arcuate curved surface. Further, like the reference surface 66 and the front curved surface 68, the rear curved surface 70 is curved so as to incline upward in the left-right direction.

As shown in Figure 13, the reference surface 66 radius of curvature: r ₁ is the curvature of the front curve surface 68 radius than the r ₂ are larger, in this embodiment, the curvature of the reference surface 66 The radius: r ₁ is approximately twice the radius of curvature of the front curved surface 68: r ₂ . Furthermore, the radius of curvature of the rear curved surface 70 is set to r ₂ that is the same as the radius of curvature of the front curved surface 68.

  Further, the maximum value of the inclination angle of the front curved surface 68 with respect to the reference surface 66: θ (see FIG. 13) is set in a range of 5 ° ≦ θ ≦ 60 °, and in this embodiment, θ = 20 °. Has been.

  According to the touch switch including the conductive member 60 having such a structure, the operation surface 62 having a shape along the movement of the distal end portion (fingertip) of the finger 48 is the same as the touch switch 10 of the first embodiment. Is realized. In particular, the formation of the front curved surface 68 prevents a decrease in detection accuracy in the input operation with the joint of the finger 48 extended, and the formation of the rear curved surface 70 allows the finger to A decrease in detection accuracy is prevented in an input operation with the 48 joints bent.

  In the touch switch of the present embodiment, the reference surface 66 is an arc-shaped concave surface that extends while curving in the front-rear direction. As a result, the fingertip is allowed to move more smoothly due to bending and stretching of the finger 48, and the change in the contact position of the fingertip with the operation surface 62 is more effectively reduced, so that the slide input detection accuracy is further enhanced.

Furthermore, the curvature of the reference surface 66 radius: r ₁ is the radius of curvature of the front curve surface 68 and the rear curved surface 70: is larger than the r _2. Therefore, in comparison with the case where the entire operation surface is formed with a uniform radius of curvature, the detection accuracy of the slide input in the extended state and the bent state of the finger 48 is ensured in the front-rear direction of the operation surface 62. It is possible to improve the operational feeling by ensuring the size.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited by the specific description. For example, although the operation surfaces 16 and 62 of the embodiment include both the front curved surfaces 42 and 68 and the rear curved surfaces 44 and 70, the rear curved surfaces 44 and 70 are not essential.

  Further, the front curved surfaces 42 and 68 are not necessarily limited to those curved in a circular arc shape with a constant curvature radius, and the curvature radius may be changed. When the curvature radii of the front curved surfaces 42 and 68 are thus changed, it is desirable that the average value of the curvature radii: r ′ is set in a range of 10 mm ≦ r ′ ≦ 3000 mm. The same applies to the rear curved surfaces 44 and 70. The average value of the radius of curvature: r ′ is the value obtained by dividing the central angle of the portion where the radius of curvature is constant by the central angle of the front curved surfaces 42, 68: α (see FIG. 6). Calculated by multiplying the radii, and the sum of the numbers of each part. More preferably, the front curved surfaces 42 and 68 (rear curved surfaces 44 and 70) are formed with a radius of curvature that satisfies the above numerical range as a whole.

  In the above-described embodiment, the operation surfaces 16 and 62 are curved in the left-right direction. However, the left-right direction is not essential. For example, the reference surfaces 40 and 66 may be flat. The operation surfaces 16 and 62 preferably have a long planar shape in the front-rear direction in order to efficiently secure an input stroke, but are not essential, for example, a circular or square shape in plan view. An operating surface can also be employed.

  Further, a thin insulator layer may be formed on the surface of the conductive member 14 and the operation surfaces 16 and 62 may be covered with an insulator. In this case, direct contact between the finger 48 and the conductive member 14 cannot occur, but by applying an alternating voltage, the insulator layer is made a dielectric, and the finger 48 and the conductive member 14 are paired with a pair of electrodes. Therefore, by detecting a change in capacitance, the operation of the finger 48 can be detected as an input. In short, in the touch switch according to the present invention, the input detection method is not particularly limited. Note that an AC voltage may be applied to a touch switch having a structure having no insulator layer, and in that case, detection of a target slide input can be realized.

  Moreover, in the said embodiment, although the structure where the voltage was applied from two or more places (2 places) with respect to the electrically-conductive member 14 is shown, even if a voltage is applied to one place with respect to the electrically-conductive member 14, for example The change in the contact position of the fingertip can be detected based on the resistance change between the voltage application portion and the fingertip contact portion. Needless to say, the voltage may be applied from a plurality of three or more locations.

  Further, for example, a grounded conductive portion is provided on the armrest 12, and an input is detected by touching the conductive portion 14 with the index finger while touching the conductive portion with the thumb and performing a sliding input. It may be. Thereby, the electrical resistance is reduced, and the detection accuracy can be improved and stabilized.

  In addition, the application range of the touch switch according to the present invention is not limited to the vehicle window opening / closing interface, and includes various input interfaces such as an input interface for operating an audio or an air conditioner, for example. It is. Furthermore, the touch switch of the present invention is not limited to automobiles.

10: Touch switch, 14, 60: Conductive member, 16, 62: Operation surface, 40, 66: Reference surface, 42, 68: Front curved surface, 44, 70: Back curved surface, 48: Finger

Claims (4)

In the touch switch for detecting the contact movement of the finger on the conductive member based on the energized state of the conductive member, a voltage is applied to the conductive member.
The operation surface of the conductive member in contact with the finger has a reference surface extending in the front-rear direction with the front end side of the finger as the front, and the operation surface extends while tilting upward from the reference surface. A touch switch comprising a front curved surface that protrudes forward and has an inclination angle that increases toward the front side, and the front curved surface has a smaller radius of curvature than the reference surface.   The back curved surface in which the operation surface of the conductive member extends from the reference surface while tilting upward toward the rear, which is the base end side of the finger, and the inclination angle with respect to the reference surface increases toward the rear side. The touch switch according to claim 1, further comprising:   3. The touch switch according to claim 1, wherein a maximum inclination angle θ of the front curved surface with respect to the reference surface is set in a range of 5 ° ≦ θ ≦ 60 °.   The touch switch according to claim 1, wherein the operation surface of the conductive member has a longitudinal direction in the front-rear direction.

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