KR102434799B1 - Steering wheel capable of hands on/off sensing - Google Patents

Abstract

A driver grip sensing steering wheel is disclosed. A driver grip sensing steering wheel according to an embodiment of the present invention includes: a rim base having a core having a rim shape and a base layer made of a polymer material surrounding the core; and a sensor pad attached to the rim base to detect the driver's hands-off and hands-on states, wherein the sensor pad can be extended to be attached along the circumference of the rim base. have.

Description

Driver grip sensing steering wheel {STEERING WHEEL CAPABLE OF HANDS ON/OFF SENSING}

The present invention relates to a steering wheel and a method for manufacturing a driver's grip detection pad that can check whether a driver's grip is sensed, and more particularly, a steering wheel equipped with a sensor pad that can check whether a user's grip is held during autonomous driving; The present invention relates to a method for manufacturing a driver's grip sensing pad.

The autonomous vehicle recognizes the surrounding environment by itself without the intervention of the driver, and controls the vehicle by judging the driving situation. Recently, these autonomous vehicles are attracting attention as a means of transportation that can reduce traffic accidents, increase traffic efficiency, save fuel, and increase driver convenience by replacing driving.

However, depending on driving conditions, there may be cases in which the driver's intervention is required. In this situation, the vehicle in the autonomous driving mode needs to immediately give the driver control over the vehicle.

Therefore, the autonomous vehicle must check whether the driver is holding the steering wheel during autonomous driving, and if the driver is not holding the steering wheel when it is necessary to transfer control to the driver, a warning is issued to the driver for safety. Needs to be.

Conventionally, it is indirectly detected whether the driver is holding the steering wheel through a camera, infrared sensor, or MDPS torque sensor applied to parts around the steering wheel where gripping occurs, but there are many cases in which misrecognition is made depending on the surrounding environment.

Accordingly, there is a need for a steering wheel to which a grip detection exclusive function is applied that does not significantly change the structure and aesthetics of the existing steering wheel while accurately checking whether the driver is gripped.

The present invention has been devised to solve and improve the problems of the prior art, and an object of the present invention is to provide a steering wheel equipped with a capacitive sensor pad capable of accurately checking whether the driver is gripped and a method of manufacturing the driver's grip detection pad.

Another object of the present invention is to provide a steering wheel capable of detecting whether a driver is holding a steering wheel in each area by separating a left area and a right area of the steering wheel.

Another object of the present invention is to provide a steering wheel capable of robustly detecting a gripping signal by correcting the change in ambient temperature.

Another object of the present invention is to provide a steering wheel capable of improving exterior quality and performance while facilitating mounting on the steering wheel by providing smooth extensibility in the circumferential direction and the steering axis direction when the steering wheel is wrapped.

A driver grip sensing steering wheel according to an embodiment of the present invention includes: a rim base having a core having a rim shape and a base layer made of a polymer material surrounding the core; a capacitive sensor pad attached to the rim base to detect the driver's hands-off and hands-on signals; and a control unit configured to receive the signal detected from the sensor pad, process a noise signal, and determine the hands-off and hands-on states of the driver based on the noise signal-processed signal.

In addition, the control unit, the driver grip sensing steering wheel to change the criterion for determining the hands-off and the hands-on state according to whether the driver is wearing gloves.

In addition, the controller may include a temperature sensor for detecting a temperature, and correct the driver's hands-off and hands-on signals according to the detected temperature.

In addition, the sensor pad, the stretchable base portion; and a conductive sheet attached to the base part and stretchable together with the base part.

In addition, when the sensor pad is mounted on the steering wheel to be elongated, the sensor pad may include a position display unit for mounting at a predetermined position of the steering wheel so that the degree of elongation is constant.

In addition, the sensor pad may be divided into a left pad for detecting whether a left area of the steering wheel is gripped, and a right pad for detecting whether a right area of the steering wheel is gripped.

Also, the controller may determine whether the signal detected from the left pad and the right pad is greater than or equal to a first reference value, respectively, to determine whether the signal is held by the left hand, the right hand, or both hands.

In addition, when the detected signals of the left pad and the right pad are similar and each is half of a full grip, it may be determined as a one-handed grip.

In addition, if the detected signals of the left pad and the right pad are both less than the first reference value, and the sum of the detected signals of the left pad and the right pad is higher than the second reference value, it is determined as one-handed grip, but higher It may be determined that the signal is gripped in the detected region.

A driver grip sensing steering wheel according to an embodiment of the present invention includes: a rim base having a core having a rim shape and a base layer made of a polymer material surrounding the core; and a sensor pad attached to the rim base to detect the driver's hands-off and hands-on states, wherein the sensor pad can be extended to be attached along the circumference of the rim base. have.

In addition, the sensor pad, the stretchable base portion; and an electrode part attached to the base part, wherein the electrode part may have a structure that can be extended in a circumferential direction of the steering wheel and an axial direction of the steering wheel.

In addition, the electrode part, as a vertical branch extending in the width direction of the base part having a meandering wave shape, a plurality of vertical branches spaced apart from each other in the circumferential direction of the steering wheel; and one or more transverse branches extending in the circumferential direction of the steering wheel to electrically connect the plurality of vertical branches to each other and having a meandering wave shape.

In addition, in a portion corresponding to the rod portion of the steering wheel, the interval between the vertical branches may be wider than in other portions.

In addition, the interval between the vertical branches may be 0.1mm to 10.0mm, and the width of the vertical branches may be 0.5mm to 10mm.

In addition, the electrode part may be a metal such as aluminum or copper, and the base part may be a nonwoven fabric or foam.

In addition, the electrode part is formed of a conductive paste, The base unit may be a non-woven fabric or foam.

In addition, the base unit may include a position display unit for mounting at a predetermined position of the steering wheel so that, when elongated to be mounted on the steering wheel, the degree of elongation is constant.

In addition, the vertical branch, a first portion extending in a straight line in the first direction at a predetermined angle in the longitudinal direction of the base portion; a second portion extending in a straight line at a predetermined angle in a direction opposite to the first direction in the longitudinal direction of the base portion; and a third part connecting the first part and the second part, wherein the third part may be rounded.

In addition, the horizontal branch is provided one at the upper end and the lower end of the vertical branch, respectively, even if any one of the horizontal branch is cut, the other horizontal branch can electrically connect the vertical branch.

According to an embodiment of the present invention, there is provided a method for manufacturing a driver's grip sensing pad mounted on a steering wheel, comprising: an electrode pad preparation step of detecting a driver's hands-off and hands-on states; Non-woven fabric preparation step for supporting the electrode pad; Non-woven laminating step of attaching the electrode pad and the non-woven fabric to each other; a cutting step of cutting the laminated electrode pad and the nonwoven fabric into a shape for attaching to the steering wheel; and a terminal attachment step of attaching a terminal for applying a current to the electrode pad to the cut electrode pad and the nonwoven fabric.

In addition, the electrode pad may be a stretchable conductive sheet, and the nonwoven fabric may be stretchable.

In addition, the electrode pad preparation step includes an electrode pad separation step of cutting the middle portion of the long electrode pad to separate the left area pad and the right area pad into two, and the nonwoven laminating step comprises separating the nonwoven fabric from the nonwoven fabric. It can be attached to the electrode pad.

In addition, the nonwoven fabric and the electrode pad It can be attached by double-sided tape.

In addition, in the cutting step, the electrode pad and the nonwoven fabric laminated may be cut using a hydraulic press or laser cutting.

In addition, the cutting step may include cutting a position display unit for mounting at a predetermined position of the steering wheel so as to make the degree of elongation constant when it is elongated to be mounted on the steering wheel.

In addition, in the terminal attachment step, the terminal may be pressed to the electrode pad using a terminal press.

According to an embodiment of the present invention, there is provided a method for manufacturing a driver's grip sensing pad mounted on a steering wheel, comprising: an electrode pad preparation step of detecting a driver's hands-off and hands-on states; Non-woven fabric preparation step for supporting the electrode pad; Non-woven laminating step of attaching the electrode pad and the non-woven fabric to each other; a cutting step of cutting the laminated electrode pad and the nonwoven fabric into a shape for attaching to the steering wheel; and a terminal attachment step of attaching a terminal for applying a current to the electrode pad to the cut electrode pad and the nonwoven fabric, wherein the electrode pad preparation step may include forming a predetermined electrode pattern. .

In addition, the electrode pad preparation step may include: a pattern mask printing step of printing an electrode pattern on a metal thin film; an etching step of forming an electrode pattern by performing an etching operation; and a peeling step of removing the remaining mask ink.

In addition, the electrode pad preparation step is based on the central portion of the long electrode pad. and an electrode pad separation step of separating the left area pad and the right area pad into two, wherein the nonwoven laminating step may attach the nonwoven fabric to the separated electrode pad.

In addition, in the step of laminating the nonwoven fabric, after the electrode pad and the nonwoven fabric are seated on a vacuum adsorption jig, respectively, the upper and lower sides of the vacuum adsorption jig may be combined to laminate the electrode pad and the nonwoven fabric.

According to the driver's grip sensing steering wheel according to an embodiment of the present invention, a capacitive sensor pad is mounted to accurately check whether the driver's grip is held.

In addition, the left area and the right area of the steering wheel are separated, so that it is possible to detect whether the driver holds the steering wheel in each area.

In addition, even when the ambient temperature changes, it is possible to robustly detect the gripping signal by correcting it.

In addition, when the steering wheel is wrapped, it is possible to improve the appearance quality and performance while facilitating mounting on the steering wheel by providing smooth extensibility in the circumferential direction and the steering axis direction.

In addition, since the sensor pad has a flexible material or shape, it can be easily expanded when the steering wheel is attached to prevent damage.

1 is a diagram illustrating a structure of a driver's grip sensing steering wheel according to an embodiment of the present invention.
2 is a block diagram illustrating a configuration of a driver grip sensing steering wheel according to an embodiment of the present invention.
3 is a diagram schematically showing the structure of a sensor pad according to an embodiment of the present invention.
4 is a diagram illustrating a change in capacitance of a sensor pad according to a driver's grip detection.
5 is a diagram illustrating a change in capacitance of a sensor pad before and after correction according to a change in temperature.
6 is a view for explaining a situation of holding the steering wheel with both hands and holding with one hand.
7 is a flowchart schematically illustrating a step of determining the grip of both hands and the grip of one hand in the driver's grip sensing steering wheel according to an embodiment of the present invention.
8 is a diagram schematically illustrating a structure of a cross-section of a driver's grip sensing steering wheel according to an embodiment of the present invention.
9 is a view for explaining in detail the overall arrangement and shape of the electrode part in the embodiment of FIG. 8 .
10 and 11 are diagrams for illustrating detailed shapes of the electrode part in FIG. 9 .
FIG. 12 is a view showing that only one horizontal branch is disposed in the lower part of FIG. 9 .
13 is a diagram illustrating a method of manufacturing a driver's grip sensing pad according to an embodiment of the present invention.
14 is a diagram illustrating a method of manufacturing a driver's grip sensing pad according to another embodiment of the present invention.
15 is a diagram illustrating a method of manufacturing a driver's grip sensing pad according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily carry out the present invention. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein. And, in order to clearly describe the embodiment of the present invention in the drawings, parts irrelevant to the description are omitted.

The terms used herein are used only to describe specific embodiments, and are not intended to limit the present invention. The singular expression may include the plural expression unless the context clearly dictates otherwise.

In the present specification, terms such as "comprise", "have" or "include" are intended to designate that the features, numbers, steps, operations, components, parts, or combinations thereof described in the specification exist, and one It may be understood that this does not preclude in advance the possibility of the presence or addition of other features or numbers, steps, operations, components, parts, or combinations thereof, or other features or more.

In addition, it should not be understood that the scope of the present invention is limited by the specific embodiment, because it does not mean that the purpose or effect presented in the present invention should be included in all or only such effects. On the other hand, the technical configuration and functions widely known and applied among the technical configurations described in the present invention and the functions exhibited by the technical configurations will be omitted from detailed descriptions.

In addition, the following embodiments are provided to more clearly explain to those of ordinary skill in the art, and the shapes and sizes of elements in the drawings may be exaggerated for more clear description.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment according to the present invention will be described.

Driver grip monitoring steering wheel

1 is a diagram illustrating a structure of a driver grip sensing steering wheel according to an embodiment of the present invention, and FIG. 2 is a block diagram illustrating the configuration of a driver grip sensing steering wheel according to an embodiment of the present invention. 3 is a diagram schematically showing the structure of a sensor pad according to an embodiment of the present invention, and FIG. 4 is a diagram illustrating a change in capacitance of the sensor pad according to the driver's grip detection.

1 to 3 , the driver's grip sensing steering wheel 100 according to an embodiment of the present invention indicates whether the driver's grip on the steering wheel, that is, Hands On and Hands Off states. A capacitive sensor pad can be used to determine The steering wheel 100 may include a rim base 110 , a sensor pad 120 , and a controller 130 .

The steering wheel 100 is wrapped around the rim base 110 manufactured by molding a polymer material such as polyurethane foam 114 on the core 112 with the sensor pad 120, and then using the leather 140 or the like. This allows the exterior to be finished. Although the sensor pad 120 is shown to surround the entire rim base 110 in the present embodiment, of course, only a portion of the perimeter that the driver's hand touches a lot may be wrapped.

The sensor pad 120 is attached to the rim base 110 to detect the driver's hands-on and hands-off signals, and a capacitive sensor may be provided. When the user grips the steering wheel 100 or releases the grip, the capacitance detected by the sensor pad 120 may be changed.

The control unit 130 may be provided on the armature portion of the steering wheel 100 , and may receive a signal detected from the sensor pad 120 , detect capacitance, and process a noise signal. Based on the signal processed by the noise signal, the controller 130 may determine the driver's hands-on and hands-off states.

When the driver grips the steering wheel 100 , the driver may grip the steering wheel 100 with bare hands or with gloves on. Also, the temperature and humidity of the hand may be different depending on the driver's condition. The capacitance detected by the sensor pad 120 may vary according to the state of the driver's hand. The control unit 130 may vary the standard for processing the noise signal according to the various states of the driver's hand.

As shown in FIG. 3 , the sensor pad 120 may be divided into a left pad for detecting whether the left area of the steering wheel 100 is gripped, and a right pad for detecting whether the right area is gripped. have. The separated spacing is, for example, 0.5 mm to 10 mm. may be, and this may be an area corresponding to the 12 o'clock or 6 o'clock position of the steering wheel 100 .

More specifically, the sensor pad 120 may include a stretchable base unit 128 and a conductive sheet 122 attached to the base unit 128 and stretchable together with the base unit 128 . Here, the base unit 128 may be provided as a whole by a stretchable material such as a nonwoven fabric, and the conductive sheet may have, for example, a structure in which a metal such as silver or copper is deposited on a stretchable fabric such as nylon. Here, the conductive sheet 122 may be divided into a left conductive sheet 122L and a right conductive sheet 122R.

The sensor pad 120 may extend in the circumferential and axial directions of the steering wheel 100 in order to be mounted on the rim base 110 of the steering wheel 100 . In this case, it is ensured that the degree of elongation of the sensor pad 120 is uniform for each product, and the elongation must be made to a predetermined degree for each section, so that the signal of the sensor pad 120 is stable over the entire area of the sensor pad 120 and can be uniform. To this end, the sensor pad 120 may be provided with a plurality of position display units 129 for mounting at a predetermined position of the steering wheel 100 so that the degree of elongation is constant. The position display unit 129 may be provided in an embossed, engraved, or concave-convex shape, and may be provided in a 'V'-shaped cut shape as in the present embodiment. Using the position display unit 129 , when the operator mounts the sensor pad 120 on the rim base 110 , the sensor pad 120 may be extended by a corresponding position of the rim base 110 to be mounted.

Referring to FIG. 4 , when the driver grips any one of the left areas of the steering wheel 100 , the detection signal L_S of the sensor pad 120 corresponding to the left area is a first Larger than the reference value (L_T), for example, may appear as 50pF. Here, the first reference value L_T may be set to 25 pF, and when the detection signal L_S of the sensor pad 120 is detected to be greater than or equal to the first reference value L_T, the controller 130 controls the left region for the It can be judged as hands-on.

On the other hand, when the driver does not grip the right area of the steering wheel 100 , the detection signal R_S of the sensor pad 120 corresponding to the right area may appear as almost OpF lower than the first reference value R_T. have. Accordingly, the controller 130 may determine that the right area is hands-off. Here, the first reference value R_T corresponding to the right region and the first reference value L_T corresponding to the left region may be set identically or may be set with a predetermined deviation.

5 is a diagram illustrating a change in capacitance of a sensor pad before and after correction according to a change in temperature.

The control unit 130 provided in the armature of the steering wheel 100 processes the signal detected from the sensor pad 120, and the sensor pad 120 detected due to self-heating and an increase in ambient temperature due to a built-in electronic device, etc. may exhibit a tendency to increase as shown in FIG. 5 . This may actually cause an error in the capacitance of the sensor pad 120 . In the present embodiment, a temperature sensor (not shown) may be provided in the control unit 130 in order to minimize a measurement error due to a change in the temperature of the surrounding environment and the steering wheel 100 . The controller 130 may actively correct the error of the detection signal of the sensor pad 120 according to the detected temperature, and maintain it constant even if the temperature changes.

6 is a view for explaining a situation of holding both hands and one hand of the steering wheel, and FIG. 7 is a schematic diagram of determining the two-handed grip and one-handed grip in the driver's grip sensing steering wheel according to an embodiment of the present invention. It is a flowchart showing

6 and 7 , the controller 130 measures the capacitance of the left sensor pad in step S110 and measures the capacitance of the right sensor pad in step S120 .

When the detection signal of both sensor pads is output above the first reference value (eg, 25pF) (S130), the controller 130 determines that the driver is holding the steering wheel 100 with both hands (S140, FIG. 6A ) Reference).

If it is not the case that the detection signals of both sensor pads are above the first reference value in step S130, it is determined which one of the two sensor pads is output above the first reference value (S150). When any one of the sensor pads is greater than or equal to the first reference value, the controller 130 determines that the driver is holding the steering wheel 100 with one hand ( S160 ).

On the other hand, if it is determined that the signals of both sensor pads are less than the first reference value in step S150 , the controller 130 may determine whether the detection signals of both sensor pads are similar to each other. When gripped with one hand in the 12 o'clock direction of the steering wheel 100 as shown in FIG. 6B , the 12 o'clock direction of the steering wheel 100 may be an area corresponding to the boundary surface of the two separated sensor pads. In this case, when the driver holds the corresponding part with one hand, the output signal in the left area and the output signal in the right area of the steering wheel 100 are similar to each other according to the size of the area touched by the driver's hand. may appear In addition, even if the output signal in the left region and the output signal in the right region are not similar to each other, the signals of both sensor pads are smaller than the first reference value, but the sum of the signals of both sensor pads is greater than the second reference value. If it is large, it is determined that the boundary surface of the 12 o'clock part or the 6 o'clock part is gripped with one hand (S180). If the sum of the signals of both sensor pads is smaller than the second reference value, the controller 130 determines that both hands are not gripped (S190).

Sensor pad that detects Hands Off and Hands On status

8 is a view for schematically explaining the structure of a cross-section of a driver's grip sensing steering wheel according to an embodiment of the present invention, and FIG. 9 is a view for explaining the overall arrangement and shape of the electrode part in detail in the embodiment of FIG. is a drawing for 10 and 11 are diagrams for illustrating detailed shapes of the electrode part in FIG. 9 .

First, referring to FIG. 8A , the steering wheel for sensing driver grip according to an embodiment of the present invention may include a rim base 110 and a sensor pad 120 . The rim base 110 may be made of a core having a rim shape of a steering wheel and a polymer material surrounding the core. The sensor pad 120 may be attached to the rim base 110 to detect the driver's hands-off and hands-on states. Here, the sensor pad 120 may be stretchable to be attached along the circumference of the rim base 110 .

Specifically, the sensor pad 120 may include a nonwoven fabric 128 as a stretchable base part and an electrode part 122 stretchably coupled to the nonwoven fabric 128 . The electrode part 122 may have a shape having a predetermined serpentine pattern as a whole, and may be made of, for example, a metal material such as copper or aluminum. The electrode part 122 may be extended in both the circumferential direction and the axial direction of the steering wheel 100 due to the serpentine shape. In addition, the electrode part 122 may be formed of a conductive paste, and the base part may be foam instead of a nonwoven fabric.

In an embodiment, the electrode part 122 in the form of a thin plate having a predetermined pattern made of copper or aluminum may be prepared through a process such as etching, which will be described later. Thereafter, the polymer substrate 126 may be attached to one surface of the electrode unit 122 . The polymer substrate 126 may serve to support the electrode part 122 having a predetermined pattern. In addition, an inorganic double-sided tape 125 may be attached to one surface of the polymer substrate 126 to which the electrode part 122 is not attached. The double-sided tape 125 may then be used for coupling with the rim base 110 . On the other hand, a double-sided tape 123 may be provided on the other surface of the electrode part 122 , and may be used to couple the electrode part 122 and the leather layer 140 which is the skin surface. Also, a terminal 121 for measuring capacitance may be connected to the metal layer 122 at a predetermined position. The terminal 121 may be provided in the form of a Keptone film, which is a form of a reinforcement film.

8B is different from FIG. 8A except that the electrode part 122 is coupled by a polymer substrate close to the leather layer 140, and the nonwoven fabric 128 is attached to the rim base 110, and is similar to FIG. 8A. A detailed description will be omitted.

Referring to FIG. 9A , the electrode part 122 may include a plurality of vertical branches 122V and one or more horizontal branches 122H. FIG. 9B is a more enlarged view of the left region of the electrode unit shown in FIG. 9A.

The vertical branch 122V is extended in the width direction of the nonwoven fabric 128 as the base portion and has a wavy shape that is meandering left and right, and a plurality of vertical branches may be installed while being spaced apart from each other in the circumferential direction of the steering wheel 100 when mounted. In addition, the plurality of vertical branches 122V need to be electrically connected to each other, and the horizontal branches 122H extending in the circumferential direction (horizontal direction in the drawing) of the steering wheel 100 and having a wavy shape meandering up and down are It may be connected to a plurality of vertical branches (122V). In the present embodiment, the horizontal branches 122H may be provided as a pair, and may be provided one at the upper and lower portions of the nonwoven fabric 128 .

Meanwhile, in the electrode part 122 , one terminal 121 may be provided in each of the lower left region and the lower right region of the sensor pad 120 . The corresponding area may be an area corresponding to 6 o'clock when mounted on the steering wheel 10 .

In addition, as shown in FIG. 9B , the degree of elongation of the sensor pad 120 is uniform for each product and a predetermined degree for each section, so that the signal can be stable and uniform over the entire area of the sensor pad 120 . To this end, the sensor pad 120 may be provided with a plurality of position display units 129 for mounting at a predetermined position of the steering wheel 100 so that the degree of elongation is constant. The position display unit 129 may be provided in an embossed, engraved, or concave-convex shape, and may be provided in a 'V'-shaped cut shape as in the present embodiment.

Meanwhile, when the steering wheel 100 is finished with leather or the like, a plurality of stitching parts for finishing the leather may be provided in the middle of the steering wheel 100 . If the vertical branches 122V of the electrode part 122 are also provided in the area B corresponding to the rod part, the disconnection of the electrode 122 due to breakage and cutting due to the folding of the electrode part 122 in the corresponding part is prevented. can occur Accordingly, the sensor pad 120 may be damaged, making it impossible to detect whether the driver is holding the steering wheel 100 . Therefore, in the present embodiment, in the region B corresponding to the stick part, the interval between the vertical branches 122V is much wider than that of other parts, so that when mounted on the steering wheel 100 of the sensor pad 120, Substantially, in the corresponding region (B), the vertical branch (122V) may be omitted.

10 and 11 are diagrams for illustrating detailed shapes of the electrode part in FIG. 9 .

Referring to FIG. 10 , the interval between the vertical branches 122V according to an embodiment of the present invention may be 0.1 mm to 10.0 mm, and the vertical branch width may be in the range of 0.5 mm to 10 mm. In addition, in the repeated wave pattern pattern, the height of the pattern may be between 3 mm and 20 mm. Thanks to this wave pattern, even if the stretchable base nonwoven fabric 128 is stretched in the transverse or longitudinal directions, that is, in the circumferential and axial directions when mounted on the steering wheel 100 , the electrode part 122 can also be stretched, resulting in disconnection. can prevent

Of course, as shown in FIG. 10 , the electrode part 122 does not have a curved shape, and the electrode part 122 in a zigzag shape may be provided in a straight line as shown in FIG. 11 . Specifically, a first portion 122V_1 in which the vertical branch 122V extends in a straight line in the first direction at a predetermined angle in the longitudinal direction of the base unit 128 and the first in the longitudinal direction of the base unit 128 . It may include a second part 122V_2 extending in a straight line at a predetermined angle in a direction opposite to the direction, and a third part 122V_3 connecting the first part 122V_1 and the second part 122V_2. . Here, the third part 122V_3 may smoothly connect the first part 122V_1 and the second part 122V_2, and may be rounded at the corners to prevent breakage during extension.

FIG. 12 is a view showing that only one horizontal branch is disposed in the lower part of FIG. 9 .

Referring to FIG. 12 , as compared with FIG. 9 , only one horizontal branch 122H is provided at the lower or upper portion to connect a plurality of vertical branches 122V. On the other hand, in FIG. 9 , one horizontal branch 122H is provided at the upper and lower ends of the vertical branch 122V, respectively, so that even if one horizontal branch 122H is cut, the other horizontal branch 122H is divided into vertical branches ( 122V) may be electrically connected to stably maintain the function of the sensor pad 120 .

Manufacturing method of driver grip sensing pad

13 to 15 are diagrams illustrating a method of manufacturing a driver's grip sensing pad according to an embodiment of the present invention. 13 and 14 are flowcharts for manufacturing a gripping sensing pad using an electrode pad composed of a conductive sheet without a pattern, and FIG. 15 is a metal thin plate such as copper or aluminum formed with a pattern as in FIG. It is a flowchart for a method of manufacturing a grip sensing pad.

First, referring to FIG. 13 , in the method of manufacturing a driver's grip sensing pad according to an embodiment of the present invention, in the raw material preparation step S210 , first, the driver's hands off and hands on states An electrode pad for detecting , and a nonwoven fabric supporting the electrode pad are prepared according to a predetermined standard. Here, the electrode pad may be a fabric having elasticity and conductivity, and for example, may have a structure in which a conductive material such as silver is laminated on nylon. In addition, the nonwoven fabric may also be a stretchable material. The nonwoven fabric and the electrode pad may be prepared by cutting into a rectangular shape of the same standard. In addition, a double-sided tape may be provided on the electrode pad.

Next, in the double-sided tape laminating step (S220), one side of the double-sided tape may be attached to the lower surface of the electrode pad. In this process, the electrode pad and the double-sided tape can be managed so that wrinkles do not occur. Next, in the cutting step (S230), a middle portion of the laminated electrode pad and the double-sided tape may be cut to be separated into two pieces. The two separate sets can each play a role in sensing the grip of the left area and the right area of the steering wheel.

Next, in the double-sided tape laminating step (S240), the two electrode pads separated in the step (S230) are spaced apart at an interval of about 1 mm to 10 mm, and then a double-sided tape is attached thereon. Here, the double-sided tape may be attached to both the two spaced apart electrode pads.

Next, in the step of laminating the nonwoven fabric ( S250 ), the nonwoven fabric having a size to cover both the lower portions of the two electrode pads spaced apart is attached. Then, in the cutting step (S260), the laminated electrode pad and the nonwoven fabric are cut together in a shape for attaching to the steering wheel to be mounted. Here, the electrode pad and the nonwoven fabric laminated may be cut using a hydraulic press or laser cutting.

In addition, the cutting step (S260) may include cutting the position display unit for mounting at a predetermined position of the steering wheel so that the degree of elongation is constant when the elongation is performed to be mounted on the steering wheel. .

Here, the other surface of the nonwoven fabric may be provided with a leather layer when mounted on the steering wheel, and the separated electrode pad uses the double-sided tape provided on the upper portion to wrap the rim base made of polyurethane, etc. It can be attached to the base.

Next, in the terminal crimping step (S270), a terminal (terminal) for measuring capacitance may be attached to both sides of the laminated and cut electrode pad and the nonwoven fabric through crimping pressure. Finally, the dimensions and appearance of the completed touchpad in step S280 are inspected and packaged.

The manufacturing method of the driver's grip sensing pad according to the above-described embodiment uses a nonwoven fabric, an electrode pad, and a double-sided tape standardized to a predetermined size, and laminating the nonwoven fabric and the electrode pad, followed by high-pressure hydraulic press or laser cutting. Since it is cut into a shape to be attached to the steering wheel using a stylus, it is easy to manage the dimensions, and it is possible to prevent the nonwoven fabric from being different in size from the electrode pad or from forming wrinkles.

14 illustrates a method of manufacturing a driver's grip sensing pad according to another embodiment of the present invention. The manufacturing method of the gripping sensing pad shown in FIG. 14 is the same up to the cutting step S330 as compared with FIG. 13, and after the cutting step S330, the two separated electrode pads are spaced apart and then both sides are on the upper side. Only the process of attaching the nonwoven fabric using the tape is different.

More specifically, in the manufacturing method shown in FIG. 14, the two separated electrode pads are spaced apart at an interval of about 1 mm to 10 mm and a double-sided tape is attached thereto. Here, the double-sided tape may be attached to both the two spaced apart electrode pads. Here, the other surface of the nonwoven fabric may be provided with a leather layer when mounted on the steering wheel, and the separated electrode pad may be attached to the rim base while wrapping the rim base made of polyurethane or the like.

15 , the manufacturing method of the driver's grip sensing pad according to another embodiment of the present invention includes an electrode pad preparation step (S410), a nonwoven fabric preparation step (S420), a nonwoven fabric lamination step (S430), and a cutting step (S440). may include.

First, the electrode pad preparation step ( S410 ) is a step of preparing an electrode pad for detecting the driver's hands-off and hands-on state, and as shown in FIG. 9 , copper or aluminum having a pattern formed therein It may include the step of manufacturing a grip sensing pad composed of a thin metal plate.

Specifically, the electrode pad preparation step ( S410 ) may include an electrode pattern mask printing step ( S412 ), an etching step ( S414 ), a peeling step ( S416 ), and an external shape processing step ( S418 ). In the electrode pattern mask printing step ( S412 ), a metal thin film such as copper or aluminum is prepared in a predetermined size, and then a pattern mask for forming a serpentine wave pattern electrode pattern is laminated as shown in FIG. 9 .

In the etching step ( S414 ), a pattern is formed by etching the metal portion of the region without the pattern mask using an etching solution or gas. Next, the mask ink remaining in the peeling step S416 is removed.

The nonwoven fabric preparation step (S420) may be performed in parallel with the electrode pad preparation step (S410). A nonwoven fabric having a predetermined size suitable for the size of the electrode pad is prepared. Here, the nonwoven fabric has an elongation, and further may be a material having elasticity.

In the nonwoven laminating step (S430), the prepared nonwoven fabric and the electrode pad are attached to each other using a double-sided tape, etc. In this case, the nonwoven fabric and the electrode pad are provided with a positioning hole for positioning when mutually attached in advance. can be processed.

In the cutting step (S440), the laminated electrode pad and the nonwoven fabric may be cut together in a shape for attaching to the steering wheel. Here, the electrode pad and the nonwoven fabric laminated may be cut using a hydraulic press or laser cutting. Here, when it is elongated to be mounted on the steering wheel, the method may include cutting a position display unit for mounting at a predetermined position of the steering wheel so that the degree of elongation is constant.

Next, in the terminal crimping step, a terminal (terminal) for measuring capacitance may be attached to both sides of the laminated and cut electrode pad and the nonwoven fabric through crimping pressure.

In the above-described embodiments, for example, in the step of laminating a nonwoven fabric (S430), the electrode pad and the nonwoven fabric are respectively seated on a vacuum adsorption jig, and then the upper and lower sides of the vacuum adsorption jig are combined to laminate the electrode pad and the nonwoven fabric. may do it

According to the driver's grip sensing steering wheel according to the above-described embodiments, the capacitive sensor pad is mounted to accurately check whether the driver's grip is held.

In addition, since the left area and the right area of the steering wheel are separated, it is possible to detect whether the driver is holding the steering wheel in each area, and it is possible to robustly detect the grip signal by correcting it even if the ambient temperature changes.

In addition, when the steering wheel is wrapped, it is possible to improve the appearance quality and performance while facilitating mounting on the steering wheel by providing smooth extensibility in the circumferential direction and the steering axis direction, and the sensor pad is made of a flexible material or shape When the steering wheel is attached by having it, it can be easily expanded to prevent damage.

Although representative embodiments of the present invention have been described in detail above, those of ordinary skill in the art to which the present invention pertains will understand that various modifications are possible within the limits without departing from the scope of the present invention with respect to the above-described embodiments. .

Therefore, the scope of the present invention should not be limited to the described embodiments, and should be defined by the claims described below as well as the claims and equivalents.

100: steering wheel, 110: rim base
120: sensor pad 130: control unit
112: core 114: polyurethane foam
122: conductive sheet, electrode part 129: position display part
128: base part, non-woven fabric 123, 125: double-sided tape
126: polymer base 140: leather layer (skin side)
121: terminal 122H: horizontal branch
122V: vertical branch

Claims (10)

A driver grip sensing steering wheel comprising:
a rim base having a core having a rim shape and a base layer made of a polymer material surrounding the core; and
and a sensor pad attached to the rim base to detect the driver's hands-off and hands-on states;
The sensor pad is extensible to be attached along the circumference of the rim base,
The sensor pad is
Stretchable base unit; and
including an electrode part attached to the base part;
The electrode part has a structure that can be extended in the circumferential direction of the steering wheel and in the axial direction of the steering wheel,
The electrode part,
a vertical branch extending in the width direction of the base part and having a meandering wave shape, a plurality of vertical branches being spaced apart from each other in the circumferential direction of the steering wheel; and
Driver grip sensing steering wheel comprising a; at least one transverse branch extending in the circumferential direction of the steering wheel to electrically connect the plurality of vertical branches to each other and having a tortuous wavy shape.
delete delete According to claim 1,
In a portion corresponding to the rod portion of the steering wheel, the distance between the vertical branches is wider than the other portions of the driver grip sensing steering wheel.
According to claim 1,
The distance between the vertical branches is 0.1mm to 10.0mm, the width of the vertical branch is 0.5mm to 10mm driver grip sensing steering wheel.
According to claim 1,
The electrode part is a metal such as aluminum or copper,
The driver's grip sensing steering wheel that the base part is a non-woven fabric or foam.
According to claim 1,
The electrode part is formed of a conductive paste,
The driver's grip sensing steering wheel that the base part is a non-woven fabric or foam.
According to claim 1,
When the base unit is elongated to be mounted on the steering wheel, the driver grip sensing steering wheel includes a position display unit for mounting at a predetermined position of the steering wheel so that the degree of elongation is constant.
According to claim 1,
The vertical branch,
a first portion extending in a straight line in a first direction at a predetermined angle in the longitudinal direction of the base portion;
a second portion extending in a straight line at a predetermined angle in a direction opposite to the first direction in the longitudinal direction of the base portion; and
a third part connecting the first part and the second part;
Driver grip sensing steering wheel, characterized in that the third part is rounded.
According to claim 1,
The horizontal branch is provided one at the upper end and the lower end of the vertical branch, and even if one of the horizontal branches is cut, the other horizontal branch electrically connects the vertical branch to the driver's grip sensing steering wheel.

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