Touch sensing structure, direction control device, touch detection system and vehicle

Abstract

The utility model discloses a touch sensing structure, a direction control device, a touch detection system and a vehicle. The conductive film comprises a first conductive skin and a first conductive layer, the first conductive skin comprises a first insulating base material and a second conductive layer, the first insulating base material is provided with a first surface and a second surface, the first conductive layer is arranged on the first surface, and the second conductive layer is attached to the first insulating base material. The second conductive layer is arranged to form a conductive relationship with the skin by directly or indirectly contacting the skin; wherein one of the first conductive layer and the second conductive layer is used for receiving an excitation signal and generating a first electric signal according to the excitation signal, and the other one is used for generating a second electric signal according to the first electric signal. According to the utility model, the touch type sensing structure can be applied to the surface of an object, has sensing and interior trimming functions, and has higher sensitivity.

Description

Technical Field

[0001] The utility model relates to a touch-type sensing structure, a direction control device, a touch detection system and a vehicle. Background Art

[0002] Steering wheels are widely used in vehicle direction control. Detecting the hands-off situation of the steering wheel is an important research direction at present. Taking cars as an example, when driving assistance is enabled, it is necessary to monitor whether the driver's hands are on the steering wheel.

[0003] At present, capacitive sensor measurement technology is a commonly used steering wheel hand-off detection technology. Capacitive sensor measurement technology uses metal film as electrode, and lays the electrode under the leather of the steering wheel. The hand does not directly touch the electrode. The hand applies force to the steering wheel, and the electrode changes its capacitance to the ground under the action of the force. Only then can the change in capacitance be analyzed to determine the contact information between the hand and the steering wheel. Since the electrode must be wrapped under the interior, it often takes three fingers to touch the steering wheel together to sense the hand on the steering wheel. In other words, the sensing sensitivity of capacitive sensor measurement technology is poor. The utility model aims to propose a sensing structure that can be applied to the steering wheel. The sensing structure has higher sensitivity than the capacitive sensor measurement technology in steering wheel hand-off detection. Based on the sensing structure, the utility model further proposes a direction control device, a touch detection system and a vehicle. Utility Model Content

[0004] In order to improve the sensing sensitivity, the utility model proposes a touch sensing structure, a direction control device, a touch detection system and a vehicle. The touch sensing structure is configured to generate a conductive relationship when its outer surface contacts the skin. As long as the skin contacts the outer surface of the touch sensing structure, the change of the electrical signal generated by the touch sensing structure can be triggered.

[0005] The utility model is realized by the following technical solutions:

[0006] In a first aspect, a touch sensing structure is provided, comprising a first conductive skin and a first conductive layer, wherein the first conductive skin comprises a first insulating substrate and a second conductive layer, wherein the first insulating substrate is provided with first and second conductive layers insulated from each other on both sides, and the second conductive layer is configured to form a conductive relationship between skin by direct or indirect contact with the skin; wherein one of the first conductive layer and the second conductive layer is used to receive an excitation signal and generate a first electrical signal according to the excitation signal, and the other is used to generate a second electrical signal according to the first electrical signal.

[0007] Optionally, the first conductive skin is a double-layer conductive skin, and the first conductive layer is a part of the first conductive skin.

[0008] Optionally, the first conductive skin is a single-layer conductive skin, and the touch sensing structure further includes a single-layer second conductive skin, and the second conductive skin has the first conductive layer; or, the first conductive skin is a single-layer conductive skin, and the first conductive layer is made of metal conductive cloth or metal foil.

[0009] Optionally, the second conductive layer is exposed; or, a third conductive layer is coated on the surface of the second conductive layer, the conductivity of the third conductive layer is different from the conductivity of the second conductive layer, and the third conductive layer is exposed.

[0010] Optionally, the second conductive layer has an outer avoidance through hole, and the first conductive layer has an inner avoidance through hole, and the outer avoidance through hole and the inner avoidance through hole are at least partially staggered.

[0011] A direction control device, comprising:

[0012] A touch sensing structure as described in any one of the above items;

[0013] A direction control body, wherein the touch sensing structure is wrapped on the surface of the direction control body.

[0014] Optionally, the second conductive layer covers the entire outer surface of the direction control body; or, the direction control body has a direction control operation area, and the second conductive layer is arranged at a position corresponding to the direction control operation area.

[0015] Optionally, the direction control body includes a steering wheel hub having a hand operation area for hand loading force, wherein the touch sensing structure covers a partial outer surface or the entire outer surface of the steering wheel hub, and the second conductive layer covers the hand operation area.

[0016] A touch detection system comprises a detection device and a direction control device as described in any one of the above items, wherein the first conductive layer and the second conductive layer are electrically connected to the detection device respectively.

[0017] Optionally, the detection device includes a first wire and a second wire;

[0018] The first wire is fixedly connected to the touch sensing structure via a first fixing structure, the first wire is electrically connected to the first conductive layer, and is insulated from the second conductive layer;

[0019] The second wire is fixedly connected to the touch sensing structure via a second fixing structure. The second wire is electrically connected to the second conductive layer and is insulated from the first conductive layer.

[0020] Optionally, the first fixing structure includes a first rivet and a first gasket, the first rivet passes through the first gasket, the first conductive layer and the first insulating substrate in sequence at the outer avoidance through hole of the second conductive layer, the first conductive wire is crimped between the head of the first rivet and the first gasket, and the first rivet is electrically connected to the first conductive layer;

[0021] The second fixing structure includes a second rivet and a second gasket. The second rivet passes through the second gasket, the second conductive layer and the first insulating substrate in sequence at the inner avoidance through hole of the first conductive layer. The second wire is crimped between the head of the second rivet and the second gasket. The second rivet and the second conductive layer are electrically connected.

[0022] Optionally, the detection device includes a control module and a signal processing module; the output end of the control module is used to transmit the excitation signal, the input side of the signal processing module is used to receive the first electrical signal and the second electrical signal, the output side of the signal processing module is connected to the input end of the control module, the output signal of the signal processing module changes with the amplitude of the second electrical signal, and the control module determines the contact information between the direction control device and the skin based on the output signal.

[0023] Optionally, the signal processing module includes a subtraction unit and a comparison unit, the subtraction unit outputs a difference signal based on the first electrical signal and the second electrical signal, the comparison unit is used to compare the difference signal with a preset fixed electrical signal and obtain the output signal, and the comparison unit is set such that: when the second conductive layer is in contact with the skin, the output signal changes.

[0024] Optionally, the subtraction operation unit includes:

[0025] A first common-mode amplifier, used to increase the driving current of the first electrical signal;

[0026] A second common-mode amplifier, used to increase the driving current of the second electrical signal;

[0027] A subtraction amplifier, wherein an inverting terminal of the subtraction amplifier is connected to an output terminal of the first non-inverting amplifier, a non-inverting terminal of the subtraction amplifier is connected to an output terminal of the second non-inverting amplifier, and an output terminal of the subtraction amplifier is connected to the comparison unit;

[0028] The comparison unit includes a comparator and a comparison circuit, wherein the comparison circuit is used to output the fixed electrical signal to the inverting terminal of the comparator, and the non-inverting terminal of the comparator is connected to the output terminal of the subtraction amplifier.

[0029] A vehicle comprises any of the above direction control devices or any of the above touch detection systems.

[0030] The utility model has the following beneficial effects:

[0031] In the utility model, a first conductive layer and a second conductive layer are respectively arranged on two surfaces of a first insulating substrate, the first insulating substrate and the second conductive layer are implemented by a first conductive skin, the second conductive layer can form a conductive connection with the skin, when one of the first conductive layer and the second conductive layer receives an excitation signal, the first conductive layer and the second conductive layer respectively generate a first electrical signal and a second electrical signal, when the skin forms a conductive relationship with the second conductive layer, the human body capacitance causes a change in the second electrical signal, so that the touch sensing structure and the product using the touch sensing structure have higher sensitivity than the capacitive sensor measurement technology; at the same time, the touch sensing structure can be directly arranged on the surface of an object, and also has an interior decoration function. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the implementation of the utility model, the following will briefly introduce the relevant drawings. It can be understood that the drawings described below are only used to illustrate some implementations of the utility model, and ordinary technicians in this field can also obtain many other technical features and connection relationships not mentioned in this article based on these drawings.

[0033] Figure 1 It is a cross-sectional view of a touch sensing structure at one position after expansion according to an embodiment of the utility model;

[0034] Figure 2 It is a cross-sectional view of another position of the touch sensing structure of one embodiment of the utility model after expansion;

[0035] Figure 3 It is a cross-sectional view of a touch sensing structure of an embodiment of the present utility model after partial expansion;

[0036] Figure 4 It is a cross-sectional view of a touch sensing structure of an embodiment of the present invention after partial expansion;

[0037] Figure 5 This is a corresponding relationship diagram of a steering wheel device according to an embodiment of the present utility model, wherein part a is a cross-sectional view of a local position of the steering wheel device after expansion, and part b is a cross-sectional view of a local position of the steering wheel device;

[0038] Figure 6 A schematic diagram of a steering wheel device according to an embodiment of the present invention;

[0039] Figure 7 It is a cross-sectional view of a touch detection system after partial expansion of an embodiment of the utility model;

[0040] Figure 8 It is a cross-sectional view of a touch detection system after partial expansion of an embodiment of the utility model;

[0041] Fig. 9 This is a principle block diagram of a touch detection system according to an embodiment of the present utility model;

[0042] Fig.10 This is a principle block diagram of a touch detection system according to an embodiment of the present utility model;

[0043] Fig.11 A circuit diagram of a touch detection system according to an embodiment of the present invention;

[0044] Fig.12 This is an excitation signal diagram of a touch detection system according to an embodiment of the present utility model;

[0045] Fig.13 This is a first electrical signal diagram of a touch detection system according to an embodiment of the present utility model;

[0046] Fig.14 A second electrical signal diagram of a touch detection system according to an embodiment of the present utility model;

[0047] Fig.15 This is a difference signal diagram of a touch detection system according to an embodiment of the present utility model;

[0048] Fig.16 This is a comparison diagram of the difference signal and the fixed electrical signal when the hand does not touch the steering wheel in one embodiment of the utility model;

[0049] Fig.17 This is a comparison diagram of the difference signal and the fixed electrical signal when the hand touches the steering wheel in one embodiment of the utility model.

[0050] The reference numerals and names in the figures are as follows:

[0051] 1. First insulating substrate; 11. First surface; 12. Second surface; 2. First conductive layer; 21. Inner avoidance through hole; 3. Second conductive layer; 31. Outer avoidance through hole; 4. Second insulating substrate; 5. Third conductive layer; 6. Steering wheel hub; 61. Hand operation area; 7. Insulating spacer layer; 8. Detection device; 81. First wire; 82. Second wire; 83. First rivet; 84. First gasket; 85. Second rivet; 86. Second gasket. DETAILED DESCRIPTION

[0052] The technical solutions in the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0053] Before further elaboration, the "touch type" involved in the present invention is explained first. The object being touched is the "touch sensing structure" described below. The object being touched generally refers to a part of the human body with skin, and the part of the human body is not limited to the skin of the hands, feet and face. For the sake of ease of expression, the "control part" is used to represent the object being touched in the subsequent explanation.

[0054] The utility model is based on the technical concept that a conductive relationship is formed when the skin and the surface of a product are in contact, and the on and off of the conductive relationship will cause a change in the electrical signal output by the product. A touch sensing structure is proposed. The touch sensing structure can be laid on the surface of an object. When the skin is in contact with the touch sensing structure, at least one of the electrical signals generated by the touch sensing structure changes. The contact relationship between the skin and the product can be detected by further analyzing the change in the electrical signal.

[0055] refer to Figure 1 and Figure 2 Understand. The embodiment of the utility model provides a touch sensing structure, including a first insulating substrate 1, a first conductive layer 2 and a flexible second conductive layer 3. The first insulating substrate 1 is made of a flexible material, and the first insulating substrate 1 has a corresponding first surface 11 and a second surface 12. The first conductive layer 2 is arranged on the first surface 11; the first conductive layer 2 can be attached to the first insulating substrate 1, or it can be simply attached to the first insulating substrate 1; the first conductive layer 2 can be arranged adjacent to the first surface 11, or it can be indirectly connected to the first surface 11 through other structures, that is, other layers can be spaced between the first conductive layer 2 and the first surface 11.

[0056] The second conductive layer 3 is attached to the first insulating substrate 1. Specifically, the second conductive layer 3 is attached to the first insulating substrate 1 through a processing technology, such as coating a conductive material on the second surface 12 to form the second conductive layer 3, or bonding the film-like second conductive layer 3 to the second surface 12 by bonding.

[0057] In some embodiments, the first conductive layer or the second conductive layer in the inner layer may also be made of conventional conductive materials. The following is an example in which the second conductive layer 3 is in the outer layer directly contactable by the manipulation part (eg, finger).

[0058] When in use, the second conductive layer 3 is closer to the control part than the first conductive layer 2; the second conductive layer 3 is configured to form a conductive relationship between the control part and the control part by direct or indirect contact; compared with the capacitive electrode, the second conductive layer 3 is more sensitive to the control part, as long as the local position of the control part (such as a finger) lightly touches (including direct and indirect contact) the second conductive layer 3, the electrical signal generated by the second conductive layer 3 will change, so that the touch sensing structure has a higher sensitivity.

[0059] The first conductive layer 2 forms an equivalent capacitance to the ground. When the first conductive layer 2 is loaded with an excitation signal, the first conductive layer 2 will generate a new electrical signal under the action of the equivalent capacitance, and the new electrical signal will change in parameters relative to the excitation signal. The first conductive layer 2 and the second conductive layer 3 are insulated by the first insulating substrate 1, so that after the first conductive layer 2 generates an electrical signal, it will affect the second conductive layer 3 to also generate an electrical signal. In the embodiment of the utility model, one of the first conductive layer 2 and the second conductive layer 3 is used to receive the excitation signal and generate a first electrical signal according to the excitation signal, and the other is used to generate a second electrical signal according to the first electrical signal. For example, after the excitation signal is loaded to the first conductive layer 2, the first conductive layer 2 generates a first electrical signal, and the second conductive layer 3 generates a second electrical signal under the action of the first electrical signal, and the DC bias of the first electrical signal and the second electrical signal are the same.

[0060] The human body is equivalent to a capacitor. When the control part does not contact the second conductive layer 3, the amplitude of the second electrical signal is relatively large. When the control part forms a conductive relationship with the second conductive layer 3, the amplitude of the second electrical signal becomes smaller due to the influence of the human body capacitance, that is, the amplitude of the second electrical signal is different due to the different contact relationship between the control part and the second conductive layer 3. The touch sensing structure can be combined with the control part to obtain the relationship between the first electrical signal and the second electrical signal by calculating the relationship between the two, and further analyze the relationship between the two to determine the hand-off situation.

[0061] The touch sensing structure is a flexible structure. Accordingly, the structure formed by the first insulating substrate 1, the first conductive layer 2 and the second conductive layer 3 is a flexible structure, so that it can be attached to the surface of an object and can be used as a wrapping. This allows people to directly or indirectly contact the second conductive layer 3 and form a conductive relationship with it. Of course, the touch sensing structure also has the function of interior decoration.

[0062] From the above description, it can be seen that the flexible touch sensing structure provided by the utility model is respectively provided with a mutually insulated first conductive layer 2 and a second conductive layer 3 on both sides of the first insulating substrate 1, and the flexible second conductive layer 3 can be electrically connected to the control part, and one of the conductive layers can receive an excitation signal, which provides structural support for detecting whether the second conductive layer 3 is in contact with the control part. When the touch sensing structure is applied to the surface of an object, it can detect the contact between the object and the control part.

[0063] In the embodiment of the utility model, the first conductive layer 2 may cover the entire first surface 11, or may partially cover the first surface 11. It should be noted that the first conductive layer 2 covers the first surface 11 as a whole, but some small holes are reserved on the first conductive layer 2 for connection or avoidance reasons. From the perspective of those skilled in the art, when the area of ​​these small holes is much smaller than the area of ​​the first surface 11, although the first surface 11 is not covered at the positions of these small holes, this situation is also understood to be that the first conductive layer 2 covers the entire first surface 11.

[0064] In the embodiment of the utility model, the second conductive layer 3 may cover the entire second surface 12, or may partially cover the second surface 12. It should be noted that the second conductive layer 3 covers the second surface 12 as a whole, but some small holes are reserved on the second conductive layer 3 for connection or avoidance reasons. From the perspective of those skilled in the art, when the area of ​​these small holes is much smaller than the area of ​​the second surface 12, although the second surface 12 is not covered at the positions of these small holes, this situation is also understood to be that the second conductive layer 3 covers the entire second surface 12.

[0065] In some embodiments, only one layer of the first insulating substrate 1 is provided between the first conductive layer 2 and the second conductive layer 3. In other embodiments, multiple layers are provided between the first conductive layer 2 and the second conductive layer 3 as long as the insulation relationship between the first conductive layer 2 and the second conductive layer 3 is ensured.

[0066] In some embodiments, the touch sensing structure includes a first conductive skin, and the first conductive skin has a first insulating substrate 1 and a second conductive layer 3. The insulating portion of the first conductive skin is the first insulating substrate 1, and the conductive portion located on the second surface 12 of the insulating portion is the second conductive layer 3. The conductive skin has high sensitivity, and a single finger touching the second conductive layer 3 can cause the second electrical signal to change. The use of leather material laid on the surface of the object can provide a better touch of the control part.

[0067] In some embodiments, the first conductive skin is a double-layer conductive skin, and the first conductive layer 2 is also a part of the first conductive skin. The cost of the double-layer conductive skin is lower than the cost of the capacitive sensor measurement technology (about 60 yuan), so the touch sensing structure has a price advantage. Figure 3As shown, in some other embodiments, as a first replacement means, the first conductive skin adopts a single-layer conductive skin, and the touch sensing structure also includes a single-layer second conductive skin, the second conductive skin has a first conductive layer 2 and a second insulating substrate 4, so that the first conductive layer 2 is attached to the first insulating substrate 1 (in some other embodiments, the second insulating substrate 4 can also be directly attached to the first insulating substrate 1). In some other embodiments, as a second replacement means, the first conductive skin adopts a single-layer conductive skin, and the first conductive layer 2 adopts a metal conductive cloth. In some other embodiments, as a third replacement means, the first conductive layer 2 adopts a metal foil, that is, the first conductive layer 2 can be made of other existing conductive materials.

[0068] In the embodiment of the utility model, the second conductive layer 3 can be used as a touch layer, and the control unit can directly contact the second conductive layer 3, or one or more new conductive layers can be coated on the second conductive layer 3, and the outermost new conductive layer is used as a touch layer, and the control unit indirectly contacts the second conductive layer 3 through the new conductive layer. This method can adjust the sensitivity of the touch sensing structure. Specifically, if Figures 1 to 3 As shown, the second conductive layer 3 is exposed, and the control unit can directly contact the second conductive layer 3, and the conductive layer has good conductivity to obtain higher sensitivity. Figure 4 As shown, as an alternative, the surface of the second conductive layer 3 is coated with a third conductive layer 5, the conductivity of the third conductive layer 5 is lower than that of the second conductive layer 3, the third conductive layer 5 is exposed, and the control part achieves electrical connection with the second conductive layer 3 by directly touching the third conductive layer 5.

[0069] The first electrical signal and the second electrical signal generated by the touch sensing structure are transmitted through the wire. Accordingly, the first conductive layer 2 and the second conductive layer 3 need to establish an electrical connection with the wire, and the first conductive layer 2 and the second conductive layer 3 need to be prevented from forming a conductive relationship. Figure 1 As shown, the second conductive layer 3 has an outer avoidance through hole 31, and the outer avoidance through hole 31 is a connection avoidance space between the first conductive layer 2 and its corresponding wire to prevent electrical conduction between the first conductive layer 2 and the second conductive layer 3; Figure 2 As shown, the first conductive layer 2 has an inner avoidance through hole 21, which is a connection avoidance space between the second conductive layer 3 and its corresponding wire to prevent conduction between the first conductive layer 2 and the second conductive layer 3; the outer avoidance through hole 31 and the inner avoidance through hole 21 are at least partially staggered, thereby further improving the reliability of the touch sensing structure.

[0070] The touch sensing structure is elaborated above in detail. Although the present invention proposes the above touch sensing structure based on improving the accuracy of hand-off detection of the vehicle steering wheel, it can be seen from the design concept of the present invention and common knowledge that the touch sensing structure can be set on any object that needs to come into contact with the skin, for example, the touch sensing structure is applied to the surface of a wearable device, or the touch sensing structure is set on a pedal, or the touch sensing structure is set on a direction control device (such as a steering wheel device, a handle).

[0071] refer to Figure 5 The embodiment of the utility model further provides another steering wheel device, comprising the touch sensing structure and the steering wheel hub 6 provided in any of the above embodiments, wherein the touch sensing structure covers the surface of the steering wheel hub 6 .

[0072] The steering wheel hub 6 has a hand operation area 61 for applying force to the steering wheel hub 6. Figure 6 As shown, a hand operation area 61 is respectively provided on the left and right sides of the steering wheel, the touch sensing structure covers at least a partial surface of the steering wheel, and the second conductive layer 3 covers the hand operation area 61 .

[0073] In some embodiments, the touch sensing structure covers the entire outer surface of the steering wheel hub 6, and the second conductive layer 3 also covers the entire outer surface of the steering wheel hub 6. Any position of the hand on the steering wheel hub 6 can be detected to obtain accurate hand-off information. In some other embodiments, as an alternative means, the touch sensing structure only covers the hand operation area 61 of the steering wheel hub 6, the second conductive layer 3 covers all hand operation areas 61, and other areas of the steering wheel hub 6 are separately wrapped with interior decoration to achieve a visual style effect different from the first two alternative means.

[0074] refer to Figure 5 In some embodiments, the steering wheel device further comprises an insulating spacer layer 7, and an insulating spacer layer 7 is provided between the touch sensing structure and the steering wheel hub 6. The steering wheel hub 6 is grounded and forms an equivalent capacitor with the first conductive layer 2 (it can also be understood that the first conductive layer 2 forms an equivalent capacitor with the ground), so that after the excitation signal is loaded on the first conductive layer 2, the first electrical signal slows down the rising and falling edges relative to the excitation signal (refer to Fig.12 and Fig.13 The insulating spacer layer 7 may be made of foam or insulating cloth.

[0075] The embodiment of the utility model also provides a direction control device, which can be set on the vehicle to control the running direction of the vehicle. The direction control device can be the above-mentioned steering wheel device, handle or other products used to control the direction. The direction control device includes a touch-sensing structure and a direction control body provided in any of the above-mentioned embodiments, and the touch-sensing structure is wrapped on the direction control body. Among them, the direction control body is the core component used to control the direction, and the direction of the vehicle can be controlled by moving the direction control body (such as rotation, flipping and linear movement). When the direction control device is a steering wheel device, the direction control body is the steering wheel body, and the steering wheel body includes the above-mentioned steering wheel hub 6. In addition, the touch sensing structure is wrapped around the direction control body 6 to form a connection relationship between the two. Under this connection relationship, the shapes of the two can have multiple relationships to form different covering relationships. For example, the direction control body 6 is annular, and the touch sensing structure can be surrounded by a hollow annular structure with the same shape as the direction control body 6. The touch sensing structure wraps the direction control body 6 and covers the entirety of the body. For another example, the direction control body 6 is annular, and the touch sensing structure can be surrounded by a hollow tubular structure. The touch sensing structure covers a section of the direction control body 6 while wrapping the direction control body 6.

[0076] In some embodiments, the second conductive layer 3 covers the entire outer surface of the direction control body, and any surface position where the control part contacts the direction control device can be detected, thereby more reliably judging whether the control part contacts the touch sensing structure. In some other embodiments, as a first replacement means, the direction control body has a direction control operation area (equivalent to the hand operation area 61 in the steering wheel device), and the control part controls the direction by applying a force to the direction control operation area. The second conductive layer 3 is arranged at a position corresponding to the direction control operation area, and no touch sensing structure is arranged on other surfaces of the direction control body. In some other embodiments, as a second replacement scheme, the difference from the first replacement means is that the entire surface of the direction control body is covered with a touch sensing structure, but the second conductive layer 3 is only provided at the position of the direction control operation area.

[0077] It should be emphasized that the touch sensing structure with a double conductive layer provided on the direction control body also has a strong anti-interference effect. Specifically, when the touch sensing structure and the heating device are used together on the steering wheel, the heating device generates electromagnetic interference when heating the steering wheel. The electromagnetic interference has little effect on the second conductive layer 3. Compared with the sensing structure with a single conductive layer, the touch sensing structure provided in any of the above embodiments has a stronger anti-interference ability to the electromagnetic interference.

[0078] The embodiment of the utility model also provides a touch detection system, including a detection device 8 and a direction control device provided by any of the above embodiments. Among them, the first conductive layer 2 and the second conductive layer 3 are electrically connected to the detection device 8 respectively; the detection device 8 is used to transmit an excitation signal, and is used to judge the hand-off situation of the second conductive layer 3 by analyzing the relationship between the first electrical signal and the second electrical signal. It is easy to understand that the above detection device 8 includes a control module to realize the functions of transmitting an excitation signal and judging the hand-off situation. The control module can be implemented by many types of processing chips in the prior art, such as a single-chip microcomputer (MCU) or a programmable logic controller (PLC). For example, a chip with model number AC78013MDQA can be used. The signal algorithm programmed in the control module has been recorded in the known technical solutions in the technical field of steering wheel hand-off detection, which is not the invention point of the utility model patent, so it will not be repeated.

[0079] Based on the above technical solution, the detection device 8 of the utility model can also include a first wire 81 and a second wire 82; the first wire 81 is fixedly connected to the touch sensing structure through the first fixed structure, the first wire 81 is electrically connected to the first conductive layer 2, and is insulated from the second conductive layer 3. The second wire 82 is fixedly connected to the touch sensing structure through the second fixed structure, the second wire 82 is electrically connected to the second conductive layer 3, and is insulated from the first conductive layer 2. The positional relationship between the first wire 81 and the second wire 82 and the steering wheel hub 6 is shown in FIG. Figure 6 The connection relationship between the first wire 81 and the second wire 82 and the contact sensing structure is shown in FIG. Figure 7 and Figure 8 .

[0080] refer to Figure 7 Understand. In some embodiments, the first fixing structure includes a first rivet 83 and a first gasket 84, the first rivet 83 passes through the first gasket 84, the first conductive layer 2 and the first insulating substrate 1 in sequence at the outer avoidance through hole 31 of the second conductive layer 3, the first wire 81 is crimped between the head of the first rivet 83 and the first gasket 84, the first rivet 83 and the first conductive layer 2 are in contact to form a conductive relationship, the first rivet 83 and the second conductive layer 3 are not in contact to insulate them from each other, or an insulating portion is arranged between the first rivet 83 and the second conductive layer 3 to insulate them from each other.

[0081] refer to Figure 8Understand. In some embodiments, the second fixing structure includes a second rivet 85 and a second gasket 86. The second rivet 85 passes through the second gasket 86, the second conductive layer 3 and the first insulating substrate 1 in sequence at the inner avoidance through hole 21 of the first conductive layer 2. The second wire 82 is crimped between the head of the second rivet 85 and the second gasket 86. The second rivet 85 and the second conductive layer 3 are in contact to form a conductive relationship. The second rivet 85 and the first conductive layer 2 are not in contact so that the two are insulated from each other. Of course, in some embodiments, an insulating portion may also be arranged between the second rivet 85 and the first conductive layer 2 so that the two are insulated from each other. In the above embodiments, there may be many forms of non-contact, such as avoidance through holes, and the length of the rivet cannot extend to the first conductive layer or the second conductive layer.

[0082] In some other embodiments, considering that the second electrical signal is relatively weak and is also mixed with noise, the first electrical signal and the second electrical signal can be operated to obtain the relationship between the two, and then the contact status between the control part and the second conductive layer 3 can be judged according to the change of the relationship to obtain more accurate contact information.

[0083] refer to Fig. 9 Understand. The detection device 8 may also include a control module and a signal processing module; the output end of the control module is used to transmit the above-mentioned excitation signal to the first conductive layer 2, the first conductive layer 2 generates a first electrical signal under the influence of the steering wheel hub 6, and the second conductive layer 3 generates a second electrical signal under the influence of the first electrical signal, the input side of the signal processing module is used to receive the first electrical signal and the second electrical signal, the signal processing module generates an output signal after processing the first electrical signal and the second electrical signal, the output side of the signal processing module is connected to the input end of the control module, the output signal of the signal processing module changes with the change of the amplitude of the second electrical signal, and the control module determines the hand-off information of the direction control device according to the output signal.

[0084] refer to Fig. 9 and Fig.10 Understand. In some embodiments, the signal processing module includes a subtraction unit and a comparison unit. The subtraction unit obtains a difference signal according to the first electrical signal and the second electrical signal. For example, the subtraction unit directly performs a subtraction operation on the first electrical signal and the second electrical signal to obtain the difference signal. For another example, the subtraction unit processes the first electrical signal to obtain a first result, processes the second electrical signal to obtain a second result, and then subtracts and amplifies the first result and the second result to obtain the difference signal. The comparison unit is used to compare the difference signal with a fixed electrical signal and obtain an output signal. The fixed electrical signal is a preset threshold of the comparison unit. In a transient state, the output result corresponding to when the difference signal is greater than the fixed electrical signal is different from the output result corresponding to when the difference signal is less than the fixed electrical signal, so that the control module can judge the contact between the control part and the second conductive layer 3 through the change information of the output signal.

[0085] refer to Fig.11 Understand. In some embodiments, the subtraction operation unit includes a first common-phase amplifier, a second common-phase amplifier, and a subtraction amplifier. The first common-phase amplifier is used to increase the driving current of the first electrical signal and output the above-mentioned first result; the second common-phase amplifier is used to increase the driving current of the second electrical signal and output the above-mentioned second result. Combining the above information, it can be seen that the DC bias of the first result and the second result is the same. The inverting end of the subtraction amplifier is connected to the output end of the first common-phase amplifier, the common-phase end of the subtraction amplifier is connected to the output end of the second common-phase amplifier, the output end of the subtraction amplifier is connected to the comparison unit, and the subtraction amplifier performs a difference operation on the first result and the second result and amplifies them to obtain a difference signal.

[0086] The first in-phase amplifier includes a resistor R1, a resistor R2 and an operational amplifier U1. The in-phase end of the operational amplifier U1 is connected to the first wire 81, the inverting end of the operational amplifier U1 is connected between the resistors R1 and R2 connected in series, the output end of the operational amplifier U1 is also connected to the resistor R2, and the resistor R1 is grounded. The second in-phase amplifier includes a resistor R3, a resistor R4, an operational amplifier U2, a resistor R11, a resistor R12 and a resistor R13, the resistors R11 and R12 form a voltage divider circuit, the voltage divider end of the voltage divider circuit is connected to the in-phase end of the operational amplifier U2 through the resistor R13, the second wire 82 is connected between the resistor R13 and the operational amplifier U2, and the output end of the operational amplifier U2 is also connected to the resistor R4. The subtraction amplifier includes resistors R6, R7, R8 and operational amplifier U3. The output end of operational amplifier U1 is connected to the inverting end of operational amplifier U3 through resistor R5. The output end of operational amplifier U2 is connected to the non-inverting end of operational amplifier U3 through resistor R7. Resistor R8 is connected between resistor R7 and operational amplifier U3. One end of resistor R6 is connected between resistor R5 and operational amplifier U3, and the other end is connected to the output end of operational amplifier U3. For other unexplained information, please refer to Fig.11 .

[0087] The comparison unit includes a comparator U4 and a comparison circuit, wherein the comparison circuit is used to output a fixed electrical signal to the inverting terminal of the comparator, and the non-inverting terminal of the comparator is connected to the output terminal of the subtraction amplifier. The comparison circuit includes a resistor R9 and a resistor R10, wherein the inverting terminal of the comparator U4 is connected between the resistor R9 and the resistor R10, the non-inverting terminal of the comparator U4 is connected to the output terminal of the operational amplifier U3, and the output terminal of the comparator U4 is connected to the input terminal of the control module.

[0088] The output end of the control module is connected to the in-phase end of the operational amplifier U1 through the resistor R14, and the first wire 81 is connected between the resistor R14 and the operational amplifier U1, so that after the control module transmits the excitation signal, the in-phase end of the operational amplifier U1 receives the first electrical signal instead of the excitation signal. The input end of the control module receives the output signal of the comparator U4, and the control module determines the contact between the control part and the second conductive layer 3 by analyzing the output signal. When the control module determines that the operating part is out of hand, it can send an alarm instruction to the alarm device of the touch detection system, and can also send a display instruction to the display device of the touch detection system.

[0089] When the touch detection system is applied to a car, it is used to detect when the hands are off the steering wheel. It can also be called a steering wheel hand-off detection system. The structure of the hand-off detection system can be seen in the above introduction to the touch detection system. Figures 11 to 17 The working principle of the hands-off steering wheel detection system is systematically explained. Figure 12-Figure 17 In the figure, the horizontal axis represents time t, and the vertical axis represents the electrical signal or voltage signal V.

[0090] The output end of the control module transmits an excitation signal, which uses a 400Hz~100KHz square wave signal, such as Fig.12 The excitation signal is transmitted to the first conductive layer 2 after passing through the resistor R14. The steering wheel hub 6 affects the excitation signal parameters, and the rising and falling edges of the waveform slow down, so that the first conductive layer 2 generates a first electrical signal, as shown in FIG. Fig.13 As shown. The first electrical signal is input to the in-phase terminal of the operational amplifier U1 through the first wire 81, and the operational amplifier U1 outputs the first result. The second conductive layer 3 is induced by the first electrical signal to generate a second electrical signal with the same DC bias. The waveform of the second electrical signal is as shown Fig.14 As shown, the second electrical signal is input to the in-phase terminal of the operational amplifier U2 through the second wire 82, and the operational amplifier U2 outputs the second result. The first result and the second result enter the operational amplifier U3 for difference calculation, and the operational amplifier U3 outputs the difference signal, such as Fig.15 The comparator U4 generates an output signal after comparing the difference signal and the fixed electrical signal and transmits it to the input end of the control module.

[0091] refer to Fig.16 Understand. When the hand is not in contact with the second conductive layer 3, the second conductive layer 3 is not affected in any way, the second electrical signal is relatively large, the difference between the first electrical signal and the second electrical signal is small, the amplitude of the difference signal is relatively small, and cannot be lower than the preset fixed electrical signal. The in-phase input of the comparator U4 is higher than the inverting input, and the comparator U4 always outputs a high level. It should be noted that Fig.16 The difference signal and the fixed electrical signal are illustrated, wherein the horizontally extending one represents the fixed electrical signal, and the one that changes periodically and has a rising edge and a falling edge is the difference signal.

[0092] refer to Fig.17 Understand. When the hand operates the steering wheel device, a conductive relationship is established between the hand and the second conductive layer 3. Affected by the capacitance of the human body, the amplitude of the second electrical signal becomes smaller, the difference between the first electrical signal and the second electrical signal becomes larger, the amplitude of the difference signal becomes larger, and the trough is lower than the fixed electrical signal. The output signal corresponding to the part of the comparator U4 whose in-phase input is lower than the inverting input is low level, that is, the output signal has a low level stage and a high level stage within one signal cycle. The control module determines that the hand is on the steering wheel when it detects that the input is a low level or a high level and a low level are interlaced. The control module determines that the hand is off the steering wheel when it detects that the input is always a high level within a preset time period, and the preset time period is not less than one cycle of the excitation signal. It should be noted that Fig.17 The diagram illustrates a difference signal and a fixed electrical signal, wherein the horizontal extension represents a fixed electrical signal, the periodically changing signal with a rising edge and a falling edge represents a difference signal, the difference signal changes from a high level to a low level, and during a time period when the voltage value of the difference signal is greater than the voltage value of the fixed electrical signal, the comparator U4 outputs a high level, and during a time period when the voltage value of the difference signal is less than the voltage value of the fixed electrical signal, the comparator U4 outputs a low level; within a preset period, when the control module receives a low-level electrical signal, it is considered that the hand is on the steering wheel, and when the control module always receives a high-level signal, it is considered that the hand is off the steering wheel.

[0093] The present utility model also provides a vehicle, including the touch detection system provided by any of the above embodiments or the direction control device provided by any of the above embodiments. The number of wheels of the vehicle is not limited, and it can be a tricycle, a four-wheel vehicle (such as a car) or a vehicle with other number of wheels; the power source of the vehicle is not limited, and it can be gasoline, diesel, electric or hybrid power; the application scenario of the vehicle is not limited, and it can carry people or goods.

[0094] In the above embodiment, the example illustrates the case where the hand-off signal is at a high level, that is, when the control module input terminal detects a low level signal within a preset time period, the hand is on the steering wheel, and when a high level signal is always detected, the hand is deemed to be off the steering wheel. Of course, in some embodiments, if the hand-off signal is at a low level, when the control module always detects a low level, the hand is deemed to be off the steering wheel. For example, low-level detection can be achieved by adjusting the access voltage of the inverting terminal of the comparator U4 and the bias voltage of the non-inverting terminal of the amplifier U2; by detecting that a low-level signal always appears within a preset time period, it is determined whether the hand is off the steering wheel, which constitutes an equivalent embodiment of the above-mentioned high-level detection method.

[0095] It should be understood that in the present application, an excitation signal is output to the first conductive layer or the second conductive layer through the control module, and the electrical signal changes of the first conductive layer and the second conductive layer are respectively obtained, and then a difference signal is obtained through subtraction operation, and the difference signal and the preset electrical signal are connected to the comparator and the signal is output.

[0096] The hand-off detection method described in the present application can sensitively detect the contact between a single finger and the second conductive layer. When a single finger contacts the second conductive layer of the direction control device, the amplitude of the second electrical signal increases so that within a preset time threshold, the control module can receive the first level signal or the periodic change between the first level signal and the second level signal. Once the hand does not contact the direction control device, the control device always receives the second level signal within the preset time threshold, i.e., it is determined that the hand is out of the direction control device. The present application can keenly perceive the change of the electrical signal and improve the sensitivity of the hand-off detection. In specific implementation, based on the above ideas, the entire Fig.11 By equivalently transforming or modifying the circuit structure in the present application, various circuits for realizing the same functions as those of the present application can be constructed by using electronic components such as operational amplifiers, differentiators, and comparators. This application will no longer elaborate on this part.

[0097] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A touch sensing structure, It is characterized in that It includes a first conductive skin and a first conductive layer, the first conductive skin includes a first insulating substrate and a second conductive layer, the first insulating substrate is provided with a first conductive layer and a second conductive layer insulated from each other on both sides, and the second conductive layer is configured to form a conductive relationship between skin by direct or indirect contact; wherein, one of the first conductive layer and the second conductive layer is used to receive an excitation signal and generate a first electrical signal according to the excitation signal, and the other is used to generate a second electrical signal according to the first electrical signal.

2. The touch sensing structure according to claim 1, It is characterized in that The first conductive skin is a double-layer conductive skin, and the first conductive layer is a part of the first conductive skin.

3. The touch sensing structure according to claim 1, It is characterized in that The first conductive skin is a single-layer conductive skin, and the touch sensing structure further includes a single-layer second conductive skin, the second conductive skin has the first conductive layer; or, the first conductive skin is a single-layer conductive skin, and the first conductive layer is made of metal conductive cloth or metal foil.

4. The touch sensing structure according to claim 1, It is characterized in that The second conductive layer is exposed; or, a third conductive layer is coated on the surface of the second conductive layer, the conductivity of the third conductive layer is different from the conductivity of the second conductive layer, and the third conductive layer is exposed.

5. The touch sensing structure according to any one of claims 1 to 4, It is characterized in that The second conductive layer has an outer avoidance through hole, the first conductive layer has an inner avoidance through hole, and the outer avoidance through hole and the inner avoidance through hole are at least partially staggered.

6. A direction control device, It is characterized in that include: The touch sensing structure according to any one of claims 1 to 5, and; A direction control body, wherein the touch sensing structure is wrapped on the surface of the direction control body.

7. The direction control device according to claim 6, It is characterized in that The second conductive layer covers the entire outer surface of the direction control body; or, the direction control body has a direction control operation area, and the second conductive layer is arranged at a position corresponding to the direction control operation area.

8. The direction control device according to claim 6, It is characterized in that The direction control body includes a steering wheel hub having a hand operation area for hand loading force, wherein the touch sensing structure covers a partial outer surface or the entire outer surface of the steering wheel hub, and the second conductive layer covers the hand operation area.

9. A touch detection system, It is characterized in that It comprises a detection device and the direction control device as claimed in any one of claims 6 to 8, wherein the first conductive layer and the second conductive layer are electrically connected to the detection device respectively.

10. The touch detection system according to claim 9, It is characterized in that The detection device includes a first conductive wire and a second conductive wire; The first wire is fixedly connected to the touch sensing structure via a first fixing structure, the first wire is electrically connected to the first conductive layer, and is insulated from the second conductive layer; The second wire is fixedly connected to the touch sensing structure via a second fixing structure. The second wire is electrically connected to the second conductive layer and is insulated from the first conductive layer.

11. The touch detection system according to claim 10, It is characterized in that The first fixing structure includes a first rivet and a first gasket, the first rivet passes through the first gasket, the first conductive layer and the first insulating substrate in sequence at the outer avoidance through hole of the second conductive layer, the first conductive wire is crimped between the head of the first rivet and the first gasket, and the first rivet is electrically connected to the first conductive layer; The second fixing structure includes a second rivet and a second gasket. The second rivet passes through the second gasket, the second conductive layer and the first insulating substrate in sequence at the inner avoidance through hole of the first conductive layer. The second wire is crimped between the head of the second rivet and the second gasket. The second rivet and the second conductive layer are electrically connected.

12. The touch detection system according to claim 9, It is characterized in that The detection device includes a control module and a signal processing module; the output end of the control module is used to transmit the excitation signal, the input side of the signal processing module is used to receive the first electrical signal and the second electrical signal, the output side of the signal processing module is connected to the input end of the control module, the output signal of the signal processing module changes with the amplitude of the second electrical signal, and the control module determines the contact information between the direction control device and the skin based on the output signal.

13. The touch detection system according to claim 12, It is characterized in that The signal processing module includes a subtraction unit and a comparison unit, the subtraction unit outputs a difference signal according to the first electrical signal and the second electrical signal, the comparison unit is used to compare the difference signal with a preset fixed electrical signal and obtain the output signal, and the comparison unit is configured such that: when the second conductive layer contacts the skin, the output signal changes.

14. The touch detection system according to claim 13, It is characterized in that The subtraction unit comprises: A first common-mode amplifier, used to increase the driving current of the first electrical signal; A second common-mode amplifier, used to increase the driving current of the second electrical signal; A subtraction amplifier, wherein an inverting terminal of the subtraction amplifier is connected to an output terminal of the first non-inverting amplifier, a non-inverting terminal of the subtraction amplifier is connected to an output terminal of the second non-inverting amplifier, and an output terminal of the subtraction amplifier is connected to the comparison unit; The comparison unit includes a comparator and a comparison circuit, wherein the comparison circuit is used to output the fixed electrical signal to the inverting terminal of the comparator, and the non-inverting terminal of the comparator is connected to the output terminal of the subtraction amplifier.

15. A vehicle, It is characterized in that It comprises the direction control device as described in any one of claims 6 to 8 or the touch detection system as described in any one of claims 9 to 14.

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