Touch sensor, switch, and method for manufacturing touch sensor

Abstract

A touch sensor (11) is provided with: a fabric (30); a base electrode (40) that is positioned on the front side or the rear side of the fabric (30); urethane (60) that is positioned on the front side of the fabric (30); a conductive part (70) that comprises a conductive yarn, is electrically connected to the base electrode (40), and is partially positioned on the front side of the urethane (60); and a non-conductive part (80) that comprises a non-conductive yarn. The non-conductive part (80) covers at least a portion of the conductive part (70) positioned on the front side of the urethane (60).

Description

Touch sensor, switch, and method of manufacturing touch sensor

[0001] The present disclosure relates to a touch sensor, a switch, and a method for manufacturing a touch sensor.

[0002] Embroidered electrodes formed by embroidering conductive threads on fabrics and the like are known (see Patent Document 1). The embroidered electrodes described in Patent Document 1 can be used as touch sensors.

[0003] Patent No. 4787161

[0004] However, when the embroidered electrode described in Patent Document 1 is used as a touch sensor, there is almost no difference in level between the fabric and the conductive thread embroidered on the fabric, so the touch sensor is flat and has little change in shape. For example, if the touch sensor is placed outside the user's field of vision, the user needs to know the position of the touch sensor by touch with their fingers, but if the touch sensor is flat and has little change in shape, it is difficult for the user to know the position of the touch sensor by touch.

[0005] Furthermore, when a touch sensor is formed by embroidering conductive thread onto fabric, the conductive thread is exposed on the surface of the touch sensor, and when a user operates the touch sensor, the user's fingers come into direct contact with the conductive thread, which can easily deteriorate due to repeated contact.

[0006] An object of the present disclosure is to provide a touch sensor, a switch, and a method for manufacturing a touch sensor that make it easy to grasp the position by touch and that is resistant to deterioration of conductive threads.

[0007] A touch sensor according to one embodiment that solves the above problem comprises a substrate, a base electrode located on the front or back side of the substrate, an elastic body located on the front side of the substrate, a conductive portion made of conductive thread that is electrically connected to the base electrode and has a portion located on the front side of the elastic body, and a non-conductive portion made of non-conductive thread, and the non-conductive portion covers at least a portion of the conductive portion located on the front side of the elastic body.

[0008] A switch according to one aspect of the present invention has a plurality of the touch sensors. A method for manufacturing a touch sensor according to one aspect of the present invention includes the steps of: positioning a base electrode on the front or back side of a substrate and an elastic body on the front side of the substrate; embroidering a conductive thread to electrically connect the conductive thread to the base electrode and position a portion of the conductive thread on the front side of the elastic body; and embroidering a non-conductive thread to cover at least a portion of the conductive thread located on the front side of the elastic body.

[0009] Figure 1A is a schematic side view of a seat, and Figure 1B is an enlarged schematic view of the seat switch and reclining switch shown in part A of Figure 1A. A schematic cross-sectional view of the seat switch. A block diagram of the seat. Figures 4A to 4D are explanatory diagrams of a manufacturing method for the seat switch and reclining switch. Figures 5A to 5C are explanatory diagrams of a manufacturing method for the seat switch and reclining switch. A schematic cross-sectional view of a modified example of the seat switch. Figures 7A to 7D are schematic diagrams showing modified examples of urethane.

[0010] 1A to 5C, an embodiment of the touch sensors 11, 21 for operating a seat formed on an automobile seat 1 embodying the present invention will be described below. When describing the orientation of the automobile or the seat 1, the right in FIG. 1A is referred to as the front, and the left as the rear.

[0011] 1A shows a schematic side view of a seat 1. The seat 1 is installed on the front right side of a vehicle. As shown in the figure, the seat 1 is equipped with a seat portion 2 that supports the user's buttocks, a backrest 3 that supports the user's upper body from behind, and a headrest 4 that supports the user's head from behind.

[0012] A pair of upper rails 5 extending in the longitudinal direction of the vehicle are fixed to a seat frame (not shown) below the seat 2. A pair of lower rails 6 extending in the longitudinal direction are also fixed to the vehicle. The upper rails 5 and the lower rails 6 are fitted together so as to be movable relative to each other, and the seat 1 moves in the longitudinal direction as the upper rails 5 move in the longitudinal direction relative to the lower rails 6. In this embodiment, the movement of the upper rails 5 is achieved by driving a seat motor 15 (see FIG. 3).

[0013] 1A around its lower end, the backrest 3 can be rotated clockwise and counterclockwise in FIG. 1A, and this rotation causes the backrest 3 to recline. In this embodiment, the rotation of the backrest 3 is performed by driving a reclining motor 25 (see FIG. 3).

[0014] As shown in Figure 1A, a seat switch 10 for operating the forward and backward movement of the seat 1 and a reclining switch 20 for operating the reclining of the backrest 3 are formed on the right side of the seat 2. The seat switch 10 and the reclining switch 20 each have a three-dimensional shape that protrudes from the side of the seat 2 toward the front in Figure 1A.

[0015] 1B shows an enlarged schematic diagram of the seat switch 10 and the reclining switch 20. As shown in the figure, the seat switch 10 is formed in a generally rectangular shape that is long in the front-to-rear direction, imitating the side shape of the seat portion 2. The reclining switch 20 is formed in a generally rectangular shape that is long in the up-down direction, imitating the side shape of the backrest 3.

[0016] (Seat Switch) As shown by the dashed lines in Fig. 1B, the seat switch 10 has three touch sensors 11. Of the three touch sensors 11, the touch sensor 11 located at the front end of the seat switch 10 is a forward movement sensor 12 that is operated when moving the seat 1 forward, and the touch sensor 11 located at the rear end is a reverse movement sensor 13 that is operated when moving the seat 1 backward. In addition, a confirmation sensor 14 is located between the forward movement sensor 12 and the reverse movement sensor 13 to prevent erroneous operation of these switches. The forward movement sensor 12, reverse movement sensor 13, and confirmation sensor 14 differ only in their positions within the seat switch 10, and all are formed as capacitance-type, or more specifically, self-capacitance, touch sensors 11.

[0017] 2, each of the three touch sensors 11 is composed of a fabric 30 as a substrate, a base electrode 40, a fixing portion 50, a urethane 60 as an elastic body, a conductive portion 70, and a non-conductive portion 80. Of these, the fabric 30, the urethane 60, and the non-conductive portion 80 are shared by the three touch sensors 11. The fabric 30 must be non-conductive and may be fabric, leather, or the like, and is preferably the surface fabric of the seat 1. The urethane 60 is preferably urethane foam.

[0018] The configuration of the seat switch 10 will be described in detail below. In FIG. 2 , the lower side of the figure is the back side and the upper side is the front side, based on the fabric 30. The front side refers to the outside of the seat 1, and the back side refers to the inside of the seat 1. Therefore, the seat switch 10 has a three-dimensional shape that protrudes from the fabric 30 of the seat 1 toward the front side. The user operates the protruding seat switch 10 and touch sensor 11. Three base electrodes 40 are arranged along the front-to-rear direction on the back side of the fabric 30. Each base electrode 40 constitutes a part of the touch sensor 11, which is, from right to left, the forward sensor 12, the confirmation sensor 14, and the reverse sensor 13. Each base electrode 40 is a self-capacitance electrode capable of generating an electric field. While the drawing shows each base electrode 40 as a rectangular box, the shape of each base electrode 40 is not limited to this. Furthermore, each base electrode 40 is not limited to a self-capacitance electrode. For example, each base electrode 40 may be a lead wire, or any other structure capable of generating an electric field.

[0019] Each base electrode 40 is fixed to the fabric 30 by a fixing portion 50. The fixing portion 50 is embroidered using an upper thread 51 and a lower thread 52, and the embroidery is machine embroidery using a sewing machine. In FIG. 2 , for convenience of explanation, the upper thread 51 and the lower thread 52 are not individually illustrated, but are illustrated as a single zigzag solid line. Of the upper thread 51 and the lower thread 52, the thread located on the back side of the fabric 30, which is the base electrode 40 side, is made of conductive thread, while the thread located on the front side of the fabric 30 may be made of either conductive or non-conductive thread. By using conductive thread as the thread on the base electrode 40 side, even when the fixing portion 50 covers the base electrode 40, the base electrode 40 can be electrically connected to the conductive portion 70 via the conductive thread of the fixing portion 50. Therefore, the upper thread 51 and the lower thread 52 that constitute the fixing portion 50 function not only as the fixing portion 50 that fixes the base electrode 40 to the fabric 30 but also as a connecting portion that electrically connects the base electrode 40 and the conductive portion 70. The fixing portion 50 is formed for each touch sensor 11, and therefore, as shown in FIG. 2, the seat switch 10 has fixing portions 50 formed at three locations.

[0020] Here, conductive thread is a thread that has the property of conducting electricity and is manufactured by twisting together conductive fibers in whole or in part. Conductive fibers include fibers in which non-conductive fibers are plated or coated with a conductive material, fibers in which a conductive material is mixed into the polymer that forms the fiber, and metallic fibers made from metal. Among these, plated threads made from plated conductive fibers in which the surface of non-conductive fibers is silver-plated are preferred because they can be used for machine embroidery using a sewing machine. Specific examples of plated threads that can be used for the conductive thread of this embodiment include Smart X (registered trademark) from Fujix Co., Ltd. and AGposs (registered trademark) from Mitsufuji Co., Ltd.

[0021] A sheet of urethane 60 is placed on the front side of the fabric 30 where the three base electrodes 40 are located, spanning the three base electrodes 40. This urethane 60 is formed in a roughly rectangular shape, which is the shape of the seat switch 10. The seat switch 10 is formed into a three-dimensional shape that is raised from the fabric 30 by the height of the urethane 60. There are no particular regulations regarding the height of the urethane 60 to be used, and it may be of any height that allows the position of the seat switch 10 to be identified by the touch of the fingers through the three-dimensional shape.

[0022] The conductive portion 70 covers the back side of the base electrode 40 together with the fixed portion 50, and a portion of the conductive portion 70 is located on the front side of the urethane 60. The conductive portion 70 is embroidered using an upper thread 71 and a lower thread 72, and the embroidery is machine embroidery using a sewing machine. Because the base electrode 40 and the urethane 60 are positioned with the fabric 30 sandwiched between them, the conductive portion 70 secures the base electrode 40 and the urethane 60 to each other via the fabric 30 in the area where the conductive portion 70 is embroidered. For ease of explanation, in FIG. 2 , the upper thread 71 and the lower thread 72 that constitute the conductive portion 70 are not individually shown, but are instead illustrated as a single zigzag dashed line. Both the upper thread 71 and the lower thread 72 are made of conductive thread. By using conductive thread for both the upper thread 71 and the lower thread 72 that constitute the conductive portion 70, the base electrode 40 is electrically connected to the conductive portion 70 directly or indirectly via the fixed portion 50. Because a portion of the conductive portion 70 electrically connected to the base electrode 40 is located on the front side of the urethane 60, the conductive portion 70 generates an electric field from the portion located on the front side of the urethane 60, thereby enabling capacitance detection. The electrical connection between the base electrode 40 and the conductive portion 70 includes both direct and indirect connection via the fixing portion 50. The embroidery pitch of the upper thread 71 and lower thread 72 that make up the conductive portion 70 is approximately 0.4 mm to 1.0 mm, but is not limited to this. Furthermore, because a conductive portion 70 is formed for each touch sensor 11, three conductive portions 70 are formed on the seat switch 10, as shown in FIG. 2 .

[0023] Furthermore, the urethane 60 is fixed to the fabric 30 by a non-conductive portion 80, and the entire front side is covered by the non-conductive portion 80. The non-conductive portion 80 is embroidered using an upper thread 81 and a lower thread 82, and the embroidery is machine-made using a sewing machine. In FIG. 2, for convenience of explanation, the upper thread 81 and the lower thread 82 that constitute the non-conductive portion 80 are not individually illustrated, but are illustrated as a single zigzag dashed line. Both the upper thread 81 and the lower thread 82 are made of non-conductive thread. Non-conductive thread is a thread that does not conduct electricity and includes common natural fibers and chemical fibers. The urethane 60 and the three conductive portions 70 located on its front side are entirely covered by the non-conductive portion 80 made of non-conductive thread and are not exposed. This prevents a user from directly touching the conductive portion 70 when operating the seat switch 10, as they would touch the non-conductive portion 80. To prevent the conductive portion 70 from being exposed, the embroidery pitch of the non-conductive thread that constitutes the non-conductive portion 80 is preferably smaller than the embroidery pitch of the conductive thread that constitutes the conductive portion 70. In Figure 2, the pitch of the non-conductive portions 80 indicated by dashed lines is shown large to make it appear as if there are gaps, but this is for the purpose of explaining the configuration of the conductive portions 70 and other portions located inside the non-conductive portions 80. Note that, in order to facilitate removal of the surrounding urethane sheet 60s, which will be described later, it is preferable to narrow the embroidery pitch of the non-conductive thread, and this pitch may be in the range of 0.1 to 0.13 mm, for example. Furthermore, on the back side of the fabric 30, the three conductive portions 70, together with the base electrode 40, are entirely covered by the non-conductive portions 80 made of non-conductive thread and are not exposed.

[0024] (Reclining switch 20) As shown in FIG. 1B , the reclining switch 20 has three touch sensors 21. Of the three touch sensors 21, the touch sensor 21 located at the front edge of the reclining switch 20 is a forward tilt sensor 22 that is operated when rotating the backrest 3 clockwise in FIG. 1B . The touch sensor 21 located at the rear edge is a backward tilt sensor 23 that is operated when rotating the backrest 3 counterclockwise in FIG. 1B . In addition, confirmation sensors 24 are located above the forward tilt sensor 22 and the backward tilt sensor 23 to prevent erroneous operation of these switches. The forward tilt sensor 22, backward tilt sensor 23, and confirmation sensor 24 are similar to the seat switch 10, except that they are formed in different positions within the reclining switch 20. Each touch sensor 21 is formed as a capacitance type, more specifically, a self-capacitance type touch sensor 21. Similar to the touch sensor 11 of the seat switch 10 shown in Fig. 2, each of the three touch sensors 21 is composed of a fabric 30 as a substrate, a base electrode 40, a fixing portion 50, a urethane 60 as an elastic body, a conductive portion 70, and a non-conductive portion 80. Of these, the fabric 30, the urethane 60, and the non-conductive portion 80 are shared by the three touch sensors 21. The fabric 30 is also shared with the seat switch 10. As such, the touch sensor 21 of the reclining switch 20 has the same configuration as the touch sensor 11 of the seat switch 10, and therefore, a description and illustration of its specific configuration will be omitted.

[0025] (Control device 100, etc.) Figure 3 shows a block diagram including the control device 100 of the seat 1. As shown in the figure, the seat 1 is equipped with the control device 100, which includes a computer 101 equipped with a CPU, ROM, and RAM, and drive circuits 102 and 103 that drive the seat motor 15 and the reclining motor 25, respectively. The forward sensor 12, backward sensor 13, and confirmation sensor 14 that constitute the seat switch 10, and the forward tilt sensor 22, backward tilt sensor 23, and confirmation sensor 24 that constitute the reclining switch 20 are each electrically connected to the control device 100. The seat motor 15 and the reclining motor 25 are also each electrically connected to the control device 100. The control device 100 determines that the capacitance detected by each touch sensor 11, 21 is on when it exceeds a certain value, and determines that the capacitance is off when it is below that value.

[0026] When the control device 100 determines that the touch sensors 11 of both the forward sensor 12 and the confirmation sensor 14 of the seat switch 10 are on, it drives the seat motor 15 via the drive circuit 102 to move the seat 1 forward. When the control device 100 determines that the touch sensors 11 of both the reverse sensor 13 and the confirmation sensor 14 of the seat switch 10 are on, it drives the seat motor 15 via the drive circuit 102 to move the seat 1 backward. On the other hand, the control device 100 does not drive the seat motor 15 in any other cases.

[0027] The control and operation of the reclining switch 20 are similar to those of the seat switch 10. When the control device 100 determines that the touch sensors 21 of both the forward tilt sensor 22 and the confirmation sensor 24 of the reclining switch 20 are on, the control device 100 drives the reclining motor 25 via the drive circuit 103 to tilt the backrest 3 forward. When the control device 100 determines that the touch sensors 21 of both the backward tilt sensor 23 and the confirmation sensor 24 of the reclining switch 20 are on, the control device 100 drives the reclining motor 25 via the drive circuit 103 to tilt the backrest 3 backward. On the other hand, the control device 100 does not drive the seat motor 15 in any other cases.

[0028] (Method of Manufacturing Seat Switch 10) A method of manufacturing the seat switch 10 will now be described with reference to Figures 4A to 5C. Figures 4A to 5C also illustrate a method of manufacturing the reclining switch 20, but because the manufacturing method is the same as that of the seat switch 10, only the method of manufacturing the seat switch 10 will be described, and a description of the method of manufacturing the reclining switch 20 will be omitted. In addition, each of Figures 4A to 5C shows a schematic plan view of the seat switch 10 and the reclining switch 20 on the left side, and a schematic cross-sectional view of the seat switch 10 on the right side.

[0029] As shown in FIG. 4A , with the back of the fabric 30 facing up, marks 40m are made on the back of the fabric 30 at three locations where the base electrodes 40 will be fixed. The marks 40m can be made, for example, by using a chalk pen or embroidery. When making the marks 40m by embroidery, the upper and lower threads used may be either conductive or non-conductive, as long as they form the marks 40m on the fabric 30. In FIGS. 4A to 5C , the areas where the seat switch 10 and the recliner switch 20 will be formed are surrounded by a two-dot chain line, but this is for ease of understanding and is not actually shown. Next, as shown in FIG. 4B , the base electrodes 40 are positioned at the three marks 40m made on the fabric 30 and temporarily secured with adhesive tape or the like (not shown).

[0030] Next, as shown in Figure 4C, the fabric 30 is turned over so that the front side faces up. The three base electrodes 40 are temporarily fixed on the back side of the fabric 30, and their positions are indicated by dashed lines on the left side of the figure. Then, each base electrode 40 is individually fixed to the fabric 30 by embroidery. Of the upper thread 51 and lower thread 52 used for embroidery, a conductive thread is used for the lower thread 52 on the side where the base electrode 40 is located. As a result, as shown in Figure 4D, each base electrode 40 is fixed to the back side of the fabric 30 by the fixing part 50 made up of the upper thread 51 and lower thread 52 indicated by solid lines.

[0031] As shown in Figure 5A, a urethane sheet 60s is placed on the front side of the fabric 30, and each base electrode 40 and the urethane sheet 60s are individually embroidered onto the urethane sheet 60s in accordance with three fixing portions 50 formed on the fabric 30 to form conductive portions 70. The upper thread 71 and bobbin thread 72 used as the conductive portions 70 are both conductive threads. As a result, three conductive portions 70 are formed on the front side of the urethane sheet 60s, with a portion exposed. Each conductive portion 70 is electrically connected to the base electrode 40 via the fixing portion 50 or directly.

[0032] Next, as shown in FIG. 5B , a non-conductive portion 80 corresponding to the shape of the seat switch 10 is formed on the urethane sheet 60s by embroidery. The urethane sheet 60s is covered with the non-conductive portion 80 in the shape of the seat switch 10. Both the upper thread 81 and the lower thread 82 of this embroidery are non-conductive. As a result, the non-conductive portion 80 covers the entire front side of the urethane sheet 60s in the shape of the seat switch 10, along with the three conductive portions 70. The three conductive portions 70 located on the back side of the fabric 30, along with the base electrode 40, are also entirely covered by the non-conductive portion 80. In FIG. 5B , the pitch of the upper thread 81 and lower thread 82 that make up the non-conductive portion 80 is exaggerated to illustrate the configuration of the conductive portion 70, etc. Then, as shown in FIG. 5C , the surrounding urethane sheet 60s is removed along the periphery of the non-conductive portion 80. Because the non-conductive portion 80 is formed by embroidery, perforations are formed in the urethane sheet 60s along the periphery of the non-conductive portion 80. The surrounding urethane sheet 60s can be removed by cutting along the perforations. As explained above, narrowing the embroidery pitch of the non-conductive thread makes it easier to remove the urethane sheet 60s. Furthermore, because the urethane sheet 60s is cut along the perforations of the non-conductive portion 80, the urethane sheet 60 does not protrude from the periphery of the non-conductive portion 80 after the urethane sheet 60s is removed. As a result, only the urethane sheet 60 covered by the non-conductive portion 80 remains, completing the seat switch 10.

[0033] (Operation of seat switch 10) Each touch sensor 11 of the seat switch 10 is of a self-capacitance type, and generates an electric field when energized. Therefore, when a user touches the surface of each touch sensor 11 with their finger, the capacitance increases. To move the seat 1 forward, the user simply touches the forward sensor 12 and the confirmation sensor 14 of the seat switch 10 with their finger simultaneously, and to move the seat 1 backward, the user simply touches the reverse sensor 13 and the confirmation sensor 14 of the seat switch 10 with their finger simultaneously. To stop the seat 1 from moving forward, the user simply releases their hand from at least one of the forward sensor 12 or the confirmation sensor 14, and to stop the seat 1 from moving backward, the user simply releases their hand from at least one of the reverse sensor 13 or the confirmation sensor 14.

[0034] (Operation of reclining switch 20) The operation of the reclining switch 20 is similar to that of the seat switch 10, and the control and operation of the forward sensor 12 and reverse sensor 13 of the seat switch 10 described above can be interpreted as the forward tilt sensor 22 and backward tilt sensor 23 of the reclining switch 20.

[0035] The seat switch 10 and the touch sensor 11 constituting the seat switch 10 according to the above embodiment can provide the following effects. The effects of the seat switch 10 and the touch sensor 11 constituting the seat switch 10 can also be achieved by the reclining switch 20.

[0036] (1) In the above embodiment, the seat switch 10 and the touch sensor 11 have urethane 60 disposed on the front side of the fabric 30, and are formed into a three-dimensional shape that is raised by the height of the urethane 60. This makes it easier to grasp the positions of the seat switch 10 and the touch sensor 11 by touch with the fingers. In addition, because the seat switch 10 and the touch sensor 11 have a three-dimensional shape, they are also easy to grasp visually.

[0037] (2) In the seat switch 10 and each touch sensor 11, the conductive portion 70 made of conductive thread, which is located on the front side of the urethane 60, is entirely covered with the non-conductive portion 80 made of non-conductive thread. Therefore, even when a user operates the seat switch 10 and each touch sensor 11, the user's fingers do not directly touch the conductive portion 70, and the conductive thread that makes up the conductive portion 70 is less likely to deteriorate.

[0038] (3) In addition, non-conductive threads have a wider variety of thread colors and materials than conductive threads, making them easier to create decorative beauty. By using non-conductive parts 80 made of non-conductive threads for the seat switch 10 and touch sensor 11 exposed on the front side, it becomes easier to match the color and texture of the seat switch 10 and touch sensor 11 with the fabric 30 of the seat 1, etc.

[0039] (4) The conductive thread used is plated thread, which is made of plated conductive fiber with silver plating on the surface of non-conductive fiber. Plated thread can be used for machine embroidery using a sewing machine, making mass production easy.

[0040] (5) The base electrode 40 is located on the back side of the fabric 30, opposite the urethane 60 on the front side. Therefore, the base electrode 40 and the wiring extending from the base electrode 40 can be arranged on the back side of the fabric 30, and are not exposed on the front side of the fabric 30, resulting in a good appearance.

[0041] (6) The touch sensor 11 is a self-capacitance touch sensor. Therefore, unlike the mutual capacitance type, it does not require electrodes on the transmitting and receiving sides, resulting in a simple configuration. (7) The embroidery pitch of the non-conductive thread that makes up the non-conductive portion 80 is smaller than the embroidery pitch of the conductive thread that makes up the conductive portion 70. Therefore, the conductive portion 70 is less likely to be exposed from the non-conductive portion 80.

[0042] (8) The seat switch 10 and the touch sensor 11 are formed on the automobile seat 1. Therefore, the seat switch 10 and the touch sensor 11 can be directly formed using the fabric 30 of the seat 1, simplifying the structure.

[0043] (9) The seat switch 10 has three touch sensors 11. Therefore, the control of the seat switch 10 can be varied depending on the touch variations on the three touch sensors 11. In particular, the three touch sensors 11 share the fabric 30, the urethane 60, and the non-conductive portion 80 in the seat switch 10. Therefore, even if the seat switch 10 has multiple touch sensors 11, the sense of unity of the shape is improved.

[0044] (10) The fabric 30 of the seat 1 is used as the fabric 30 of the seat switch 10 and the touch sensor 11. Therefore, the seat switch 10 and the touch sensor 11 can be formed directly on the fabric 30 of the seat 1.

[0045] The above embodiment may be modified as follows: The modifications described for the seat switch 10 and the touch sensor 11 can also be applied to the reclining switch 20 and the touch sensor 21.

[0046] The touch sensor 11 may be used for purposes other than automobile seats 1. For example, the touch sensor 11 may be provided on seats 1 in airplanes, trains, and movie theaters, or on home appliances, furniture, stuffed toys, and other toys. Furthermore, the touch sensor 11 may be formed on the instrument panel inside a vehicle and used for adjusting the air conditioner or sound.

[0047] The touch sensor 11 may also be used as a switch used in a building, such as a touch switch for an automatic door, or a destination floor switch or open / close switch for an elevator. The position where the touch sensor 11 is formed is not limited to the seat 1, and it may be provided on the door trim, etc. The touch sensor 11 that operates the driver's seat 1 may be formed on the passenger seat 1.

[0048] The touch sensor 11 is used as a switch for moving the seat 1 forward and backward and for reclining the backrest 3, but it may also be applied to other operations of the seat 1, such as moving the headrest 4 up and down, changing the width or thickness of the backrest 3, or operating the ottoman.

[0049] Although the seat switch 10 has three touch sensors 11, one, two, or four or more touch sensors 11 may be provided depending on the application. The touch sensors 11 are of the self-capacitance type, but they may also be of the mutual capacitance type. In this case, the base electrode 40 used for one touch sensor 11 becomes a pair of electrodes having a transmitting side and a receiving side.

[0050] The control of the touch sensor 11 is not limited to the above embodiment. For example, the seat motor 15 may be controlled to operate only when the forward movement sensor 12 or the reverse movement sensor 13 is touched once the confirmation sensor 14 is touched, even if the hand is not touched thereafter. Also, the confirmation sensor 14 itself may not be provided, and the seat motor 15 may be controlled to start operating when the forward movement sensor 12 or the reverse movement sensor 13 is continuously touched for a predetermined period of time. The operation control of the seat 1 may be set as appropriate.

[0051] The non-conductive thread constituting the non-conductive portion 80 is not limited to one type, and the thread color may be changed depending on the location of the conductive portion 70. This makes it easier to visually grasp the position of the touch sensor 11. Furthermore, the non-conductive portion 80 may use a non-conductive thread that has a different tactile feel depending on the conductive portion 70.

[0052] The non-conductive portion 80 only needs to cover at least a portion of the conductive portion 70 located on the front side of the urethane 60. Even if the non-conductive portion 80 only covers a portion of the conductive portion 70, the conductive portion 70 at the covered portion is less likely to deteriorate.

[0053] The non-conductive portion 80 only needs to cover a portion of each of the three conductive portions 70 and the base electrode 40 on the back side of the fabric 30, and a portion of each of the three conductive portions 70 and the base electrode 40 may be exposed.

[0054] Although urethane 60 is used as the elastic body, elastic materials other than urethane may also be used. As shown in Figure 6, the base electrode 40 may be placed on the front side of the fabric 30, i.e., between the fabric 30 and the urethane 60. In this case, conductive threads are used for both the upper thread 51 and the lower thread 52 that make up the fixing part 50. By using conductive threads for the upper thread 51 and the lower thread 52, even when the base electrode 40 is located on the front side of the fabric 30, the base electrode 40 can be electrically connected to the conductive part 70 on the back side of the fabric 30 via the conductive upper thread 51 and the lower thread 52.

[0055] In this embodiment, one sheet of urethane 60 is shared by the three touch sensors 11 of the seat switch 10. However, multiple stacked sheets of urethane 60 may also be used. For example, as shown in FIG. 7A , two sheets of urethane 60 may be used for the forward sensor 12 and the reverse sensor 13 of the seat switch 10, and a single sheet of urethane 60 may be used for the confirmation sensor 14, resulting in varying heights. In this way, the confirmation sensor 14 is relatively lower in the seat switch 10, making it easier to grasp its position by touch even when multiple touch sensors 11 are formed. FIG. 7A only illustrates the fabric 30, base electrode 40, and urethane 60; other components are omitted. The same applies to FIGS. 7B to 7D .

[0056] Furthermore, when touch sensors 11 are formed in two locations, some of the urethane 60 may be double-layered as shown in FIG. 7B . Furthermore, as shown in FIG. 7C , the height of the urethane 60 for each touch sensor 11 may be three levels, with one to three layers of urethane 60 stacked. For example, in the configuration of FIG. 7A , in the conductive portion 70 formation process, one urethane sheet 60s is placed, and the conductive portion 70 of the central touch sensor 11 is formed by embroidery. Next, a second urethane sheet 60s is placed over two locations of the first urethane sheet 60s, excluding the center, and conductive thread is embroidered on top of it to form the two conductive portions 70. Next, non-conductive portions 80 are formed on top of them, and then the surrounding urethane sheet 60s is removed along the outer edge of the non-conductive portion 80.

[0057] As shown in Figure 7D, a urethane 60 having a slope whose height changes continuously may be used. In this case, it is preferable to use a single piece of urethane 60 having such a sloped surface. Furthermore, a urethane 60 having a slope whose height changes continuously may also be used for switches such as slide switches whose output changes depending on the position of the touch.

[0058] A vibration motor may be attached to the back of the fabric 30 corresponding to the touch sensor 11, and the vibration of the vibration motor may be used as a means for notifying the user of an operation or action. For example, after the user operates the seat switch 10, the control device 100 may drive the seat motor 15 forward and simultaneously vibrate the vibration motor. This allows the user to receive feedback on the operation via vibrations to the fingers. In this case, a vibration motor may be provided that imparts different vibrations in response to different actions, such as moving forward or backward. Furthermore, sound may be used in combination with the vibration motor, or sound alone may be used as a means for notifying the user.

[0059] If the conductive portion 70 and the base electrode 40 can be directly electrically connected, there is no need to use conductive thread for the upper thread 51 or the lower thread 52 of the fixed portion 50.

[0060] DESCRIPTION OF SYMBOLS 1...Seat 2...Seat portion 3...Backrest 10...Seat switch (switch) 11...Touch sensor 12...Forward sensor 13...Backward sensor 14...Confirmation sensor 15...Seat motor 20...Reclining switch (switch) 21...Touch sensor 22...Backward tilt sensor 23...Forward tilt sensor 24...Confirmation sensor 25...Reclining motor 30...Fabric (base material) 40...Base electrode 50...Fixing portion 60...Urethane (elastic body) 70...Conductive portion (conductive thread) 80...Non-conductive portion (non-conductive thread)

Claims

1. A touch sensor comprising: a substrate; a base electrode located on the front or back side of the substrate; an elastic body located on the front side of the substrate; a conductive portion made of conductive thread, electrically connected to the base electrode and a portion of which is located on the front side of the elastic body; and a non-conductive portion made of non-conductive thread, wherein the non-conductive portion covers at least a portion of the conductive portion located on the front side of the elastic body.

2. The touch sensor of claim 1, wherein the conductive thread comprises plated conductive fiber.

3. The touch sensor of claim 1, wherein the base electrode is located on the back side of the substrate.

4. The touch sensor according to claim 1, wherein the touch sensor is a self-capacitance touch sensor.

5. The touch sensor according to claim 1, wherein the non-conductive portion covers the entire front side of the conductive portion.

6. A touch sensor as described in claim 1, wherein the conductive portion is formed by embroidering with the conductive thread and the non-conductive portion is formed by embroidering with the non-conductive thread, and the embroidery pitch of the non-conductive thread is smaller than the embroidery pitch of the conductive thread.

7. The touch sensor according to claim 1, wherein the touch sensor is formed in a seat.

8. A switch having a plurality of the touch sensors according to claim 1.

9. The switch according to claim 8, wherein the non-conductive portions are formed of non-conductive threads of different colors for each conductive portion.

10. A method for manufacturing a touch sensor, comprising the steps of: positioning a base electrode on the front or back side of a substrate and an elastic body on the front side of the substrate; embroidering a conductive thread to electrically connect the conductive thread to the base electrode and position a portion of the conductive thread on the front side of the elastic body; and embroidering a non-conductive thread to cover at least a portion of the conductive thread positioned on the front side of the elastic body.

11. The method for manufacturing a touch sensor according to claim 10, wherein the embroidery pitch of the non-conductive thread is smaller than the embroidery pitch of the conductive thread.

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