Pressure sensor assembly for touch pen and touch pen

Abstract

A pressure sensor assembly for a stylus and a stylus. The pressure sensor assembly comprises an elastic element, a strain gauge, a fixing part and a force transmission part. The elastic element has a strain concentration area, and the strain gauge is attached to the strain concentration area of ​​the elastic element; the fixing part is used to fix the elastic element; and the force transmission part is used to transmit the force when the stylus is in use to the elastic element. When writing, the force transmission part transmits the writing force of the pen tip to the elastic element, thereby causing the elastic element to generate strain, and then the strain change is collected by the strain gauge arranged on the elastic element, and finally an electrical signal related to the magnitude of the writing force is output.

Description

Technical Field

[0001] The present invention belongs to the technical field of pressure sensors, and in particular relates to a pressure sensor assembly for a touch pen and a touch pen. Background Art

[0002] In order to truly reflect the writing effect of pen on paper, sensors are usually set inside the stylus to simulate the handwriting and trajectory when writing, giving users a better experience. The sensors used in existing styluses are based on grating, inductive, capacitive, electromagnetic and other principles. The main function is to convert the handwriting and trajectory into electrical signals through these sensors, and finally reproduce the handwriting and trajectory on the corresponding display through software. These displays can be built-in or attached to various electronic devices that use styluses, such as mobile phones, tablets, computers, TVs, and handwriting boards.

[0003] The sensors based on these principles are affected by principles, structures, circuits, etc., and have a series of problems such as slow response speed, poor linearity, poor real-time performance, intermittent lines (ink leakage), and asynchronous handwriting. They cannot reflect the depth, thickness, or even shadow reproduction of handwriting in real time, and cannot be used in professional painting, design and other fields. There are major defects in customer experience. Of course, some problems can be solved by complicating the structure and circuit, but it is difficult to implement, has low reliability, poor performance, and high cost, which makes it less competitive for electronic consumer products. Summary of the invention

[0004] The object of the present invention is to provide a pressure sensor assembly for a stylus pen and a stylus pen to solve the above-mentioned problem.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A pressure sensor assembly for a touch pen comprises an elastic element, a strain gauge, a fixing piece and a force transmission piece; the strain gauge is arranged on the elastic element, one side of the elastic element is arranged on the fixing piece, and the other side is connected to the force transmission piece.

[0007] Furthermore, the elastic element includes a first plane, a second plane, a third plane, a fourth plane and a fifth plane; the first plane and the third plane are respectively and vertically fixedly arranged on the same side at both ends of the second plane; the fourth plane is vertically fixedly arranged at the end of the first plane, and the fifth plane is vertically fixedly arranged at the end of the third plane.

[0008] Furthermore, the fourth plane and the fifth plane are arranged to face each other or in opposite directions.

[0009] Furthermore, when the fourth plane and the fifth plane are arranged facing each other, a gap is left between the fourth plane and the fifth plane, or the fourth plane and the fifth plane are connected to form a plane, one end of which is fixedly connected to the first plane or the third plane.

[0010] Furthermore, the fourth plane and the fifth plane are both fixedly arranged on the fixing member or the force transmission member; and the strain gauge is arranged on the first plane or the third plane of the elastic element.

[0011] Further, when the fourth plane and the fifth plane are both fixedly arranged on the fixing member, the force transmission member is arranged on the inner side or the outer side of the second plane.

[0012] Furthermore, the force transmission member includes a first end and a second end; the second end of the force transmission member is fixedly arranged at the end of the first end of the force transmission member; when the force transmission member is on the inner side of the second plane, the second end of the force transmission member is arranged through the third plane, and when the force transmission member is on the outer side of the second plane, the second end of the force transmission member is located on the outer side of the third plane.

[0013] Further, when the fourth plane and the fifth plane are both fixedly arranged on the force transmission member, the second end of the force transmission member passes through the third plane or is located outside the third plane.

[0014] Furthermore, a pen holder is fixedly arranged on the outside of the fixing member.

[0015] Furthermore, a stylus pen is provided, the stylus pen comprising the pressure sensor assembly according to any one of claims 1 to 5.

[0016] Compared with the prior art, the present invention has the following technical effects:

[0017] The sensor assembly for a stylus provided in the present application can transmit the touch force of the pen tip to the first end of the force transmission member through the second end of the force transmission member, thereby driving the first plane and the third plane of the elastic element to generate strain, and then converting the strain into an electrical signal through a strain gauge arranged on the first plane or the third plane of the elastic element, thereby realizing the conversion from touch force to electrical signal.

[0018] When the angle and size of the touch force change, the electrical signal output by the pressure sensor component also changes, and through real-time communication between the stylus and the display screen, what is reflected on the display screen is a line whose thickness changes with the touch force.

[0019] The present invention adopts the principle of strain sensor to realize signal transmission, with a comprehensive accuracy of 0.3%, an operating life of more than one million times, high reliability, strong anti-interference ability, relatively low manufacturing cost, and excellent overall performance, which meets the market demand of consumer electronic products. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the basic principle of the present invention;

[0021] Figure 2 A schematic diagram of the structure of the pressure sensor assembly provided by the present invention;

[0022] Figure 3 A schematic diagram of the structure of a pressure sensor assembly provided by the present invention installed in a pen barrel;

[0023] Figure 4 Another structural schematic diagram of the pressure sensor assembly provided by the present invention;

[0024] Figure 5 Another structural schematic diagram of the pressure sensor assembly provided by the present invention;

[0025] Figure 6 Another structural schematic diagram of the pressure sensor assembly provided by the present invention;

[0026] Figure 7 Another schematic diagram of the structure of the elastic element in the pressure sensor assembly provided by the present invention;

[0027] Figure 8 Another schematic diagram of the structure of the elastic element in the pressure sensor assembly provided by the present invention;

[0028] Fig. 9 Another schematic diagram of the structure of the elastic element in the pressure sensor assembly provided by the present invention;

[0029] Description of reference numerals:

[0030] 1——elastic element; 11——first plane of elastic element; 12——second plane of elastic element;

[0031] 13——the third plane of the elastic element; 14——the fourth plane of the elastic element; 15——the fifth plane of the elastic element; 2——strain gauge; 3——fixing part; 4——force transmitting part; 41——the first end of the force transmitting part; 42——the second end of the force transmitting part; 5——pen holder. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clearly understood, the following drawings and detailed descriptions will be used to illustrate the spirit of the contents disclosed in the present application. After understanding the embodiments of the contents of the present application, any technician in the technical field can make changes and modifications according to the methods taught by the present application without departing from the scope of the contents of the present application.

[0033] A pressure sensor assembly for a stylus pen based on the resistance strain principle. The pressure sensor assembly adopts a frame force measurement structure to convert the writing force of the stylus pen tip into resistance change or a small voltage electrical signal. The main features are: the left and right sides are fixed supports and force-applying motion end faces, one side is fixed to the pen holder, and the other side is fixed to the main shaft at a certain distance and moves up and down with the pressure of the pen tip. The upper and lower surfaces are force-deformed springs, forming a stable frame beam force measurement structure as a whole, which accurately reflects the pressure of the pen tip.

[0034] According to a preferred solution, the pressure sensor assembly includes an elastic element, a strain gauge, a fixing member and a force transmission member. The elastic element has a strain concentration area, and the strain gauge is attached to the strain concentration area of ​​the elastic element; the fixing member is used to fix the elastic element; and the force transmission member is used to transmit the force when the stylus is used to the elastic element.

[0035] The elastic element is a C-shaped thin plate structure having at least a first plane, a second plane, and a third plane, wherein the first plane is the upper part of the C-shaped structure, the second plane is the left side of the C-shaped structure, and the third plane is the lower part of the C-shaped structure, and the three planes are connected in sequence. The second plane is vertically arranged, and the angle between the first plane and the second plane is between 85° and 95°. The third plane is arranged parallel to the first plane.

[0036] Further, the distance from the end of the elastic element on the first plane away from the second plane to the second plane is equal to the distance from the end of the elastic element on the third plane away from the second plane to the second plane. The end of the elastic element on the first plane away from the second plane can be extended in a direction parallel to the second plane to generate a fourth plane. The end of the elastic element on the third plane away from the second plane can be extended in a direction parallel to the second plane to generate a fifth plane.

[0037] Furthermore, the dimensions of the first plane and the third plane of the elastic element are between 2mm×2mm and 10mm×10mm, and the vertical dimension of the second plane is between 5mm and 25mm.

[0038] Furthermore, the force transmission member includes a first end and a second end, the first end and the second end are opposite ends of the force transmission member, the first end is used to be fixed to the elastic element, and the second end is used to load force. The second end of the force transmission member is located below the third plane of the elastic element.

[0039] Furthermore, the elastic element, the fixing member and the force transmission member can be installed in the following four ways:

[0040] In the first installation mode, the first end of the force transmission member is fixedly arranged with the outer plane of the second plane of the elastic element, and the end of the first plane of the elastic element away from the second plane or the fourth plane extending outward and the end of the third plane of the elastic element away from the second plane or the fifth plane extending outward are fixedly arranged with the fixing member. The strain gauge is arranged on the first plane or the third plane of the elastic element.

[0041] In the second installation mode, the first end of the force transmission member is fixedly arranged with the inner plane of the second plane of the elastic element, and the fourth plane on the first plane of the elastic element away from the end of the second plane or extending outward and the fifth plane on the third plane of the elastic element away from the end of the second plane or extending outward are both fixedly arranged with the fixing member. The third plane of the elastic element is provided with a through hole, and the second end of the force transmission member passes through the through hole on the third plane of the elastic element. The strain gauge is arranged on the first plane of the elastic element.

[0042] In a third installation method, the fixing member is fixedly arranged with the second plane of the elastic element, and the end of the first plane of the elastic element away from the second plane or the fourth plane extending outward and the end of the third plane of the elastic element away from the second plane or the fifth plane extending outward are fixedly arranged with the first end of the force transmission member. The strain gauge is arranged on the first plane or the third plane of the elastic element.

[0043] In the fourth installation mode, the fixing member is fixedly arranged with the second plane of the elastic element, and the fourth plane on the first plane of the elastic element which is away from the second plane or extends outwardly and the fifth plane on the third plane of the elastic element which is away from the second plane or extends outwardly are fixedly arranged with the first end of the force transmission member. A through hole is arranged on the third plane of the elastic element, and the second end of the force transmission member passes through the through hole on the third plane of the elastic element. The strain gauge is arranged on the first plane of the elastic element.

[0044] The strains of the first plane and the third plane in the area where the strain gauges are attached are between 100 με and 1000 με.

[0045] Furthermore, the elastic element may be formed by one-time stamping or by separate welding.

[0046] Furthermore, the elastic element, the fixing member and the force transmission member may be fixed by welding, riveting or threaded connection.

[0047] Furthermore, a stylus pen is provided, comprising the above-mentioned pressure sensor assembly for the stylus pen based on the strain gauge principle.

[0048] The basic principle diagram of the present invention is shown in Figure 1The core structure of the sensor assembly is a frame type. When in use, one side is fixed and the other side is loaded, forming a parallel beam structure as a whole and generating positive and negative strains on the upper and lower end faces of the frame. The strain is then collected by the strain gauge set on the upper or lower end face and the corresponding analog signal is output.

[0049] A schematic diagram of a structure of an embodiment of a strain gauge pressure sensor assembly for a stylus pen provided in the present application can be found in Figure 2 .

[0050] The elastic element 1, strain gauge 2, fixing member 3 and force transmission member 4 are included. One end of the first plane 11 of the elastic element 1 away from the second plane 12 extends outward along a direction parallel to the second plane to generate a fourth plane 14, and one end of the third plane 13 away from the second plane 12 extends outward along a direction parallel to the second plane to generate a fifth plane 15.

[0051] The fixing member 3 is fixed to the fourth plane 14 and the fifth plane 15 at the same time, and the fixing method can be welding, riveting, or threaded connection.

[0052] The strain gauge 2 is disposed on the first plane 11 of the elastic element 1 , and can also be disposed on the third plane 13 of the elastic element 1 , because the first plane 11 and the third plane 13 form a parallel beam structure, and both are strain collection surfaces.

[0053] The first end 41 of the force transmission member 4 is fixedly arranged on the outer side of the second plane 12 of the elastic element 1, and the fixing method can be welding, riveting, or threaded connection. The second end 42 of the force transmission member 4 extends downward along the outer side of the second plane 12 of the elastic element 1 and is located at the lower part of the third plane 13 of the elastic element 1.

[0054] according to Figure 2 A structure of a pressure sensor assembly is provided, and a schematic diagram of the pressure sensor assembly installed in a stylus is shown in FIG. Figure 3 .

[0055] The fixing member 3 of the pressure sensor assembly is fixed to the pen barrel 5, and the fixing method can be welding, riveting, or threaded connection. Of course, if conditions permit, the fixing member 3 of the pressure sensor assembly can be removed, and the elastic element 1 is directly fixed to the pen barrel 5.

[0056] The touch force F is transmitted to the first end 41 through the second end 42 of the force transmission member 4. Since the first end 41 of the force transmission member 4 is fixed to the second plane 12 of the elastic element 1, the elastic element 1 will be strained, such as Figure 2 As shown by the dotted line, one side of the first plane 11 and the third plane 13 of the elastic element 1 is positive strain, and the other side is negative strain. The strain gauge 2 attached to the first plane 11 or the third plane 13 of the elastic element 1 collects the strain on both sides and outputs corresponding electrical signals.

[0057] The structural diagram of another embodiment of a strain gauge pressure sensor assembly for a stylus pen provided in the present application can be found in Figure 4 .

[0058] The elastic element 1, strain gauge 2, fixing member 3 and force transmission member 4 are included. One end of the first plane 11 of the elastic element 1 away from the second plane 12 extends outward along a direction parallel to the second plane to generate a fourth plane 14, and one end of the third plane 13 away from the second plane 12 extends outward along a direction parallel to the second plane to generate a fifth plane 15.

[0059] The fixing member 3 is fixed to the fourth plane 14 and the fifth plane 15 at the same time, and the fixing method can be welding, riveting, or threaded connection.

[0060] The strain gauge 2 is disposed on the first plane 11 of the elastic element 1 .

[0061] The third plane 13 of the elastic element 1 is provided with a through hole.

[0062] The first end 41 of the force transmission member 4 is fixedly arranged on the inner side of the second plane 12 of the elastic element 1, and the fixing method can be welding, riveting, or threaded connection. The second end 42 of the force transmission member 4 passes through the through hole of the third plane 13 of the elastic element 1 and is located at the lower part of the third plane 13 of the elastic element 1.

[0063] The structural diagram of another embodiment of a strain gauge pressure sensor assembly for a stylus pen provided in the present application can be found in Figure 5 .

[0064] The elastic element 1, the strain gauge 2, the fixing member 3 and the force transmission member 4 are included. The end of the first plane 11 of the elastic element 1 away from the second plane 12 extends outward along a direction parallel to the second plane to generate a fourth plane 14, and the end of the third plane 13 away from the second plane 12 extends outward along a direction parallel to the second plane 12 to generate a fifth plane 15.

[0065] The fixing member 3 is fixed to the second plane 12 of the elastic element 1, and the fixing method can be welding, riveting, or threaded connection.

[0066] The strain gauge 2 is disposed on the first plane 11 or the third plane 13 of the elastic element 1 .

[0067] The first end 41 of the force transmission member 4 is fixedly arranged with the fourth plane 14 and the fifth plane 15 of the elastic element 1, and the fixing method can be welding, riveting, or threaded connection. The second end 42 of the force transmission member 4 extends downward along the outer side of the second plane 12 of the elastic element 1 and is located at the lower part of the third plane 13 of the elastic element 1.

[0068] The structural diagram of another embodiment of a strain gauge pressure sensor assembly for a stylus pen provided in the present application can be found in Figure 6 .

[0069] The elastic element 1, strain gauge 2, fixing member 3 and force transmission member 4 are included. One end of the first plane 11 of the elastic element 1 away from the second plane 12 extends outward along a direction parallel to the second plane to generate a fourth plane 14, and one end of the third plane 13 away from the second plane 12 extends outward along a direction parallel to the second plane to generate a fifth plane 15.

[0070] The fixing member 3 is fixed to the second plane of the elastic element 1, and the fixing method can be welding, riveting, or threaded connection.

[0071] The strain gauge 2 is disposed on the first plane 11 of the elastic element 1 .

[0072] The third plane 13 of the elastic element 1 is provided with a through hole.

[0073] The first end 41 of the force transmission member 4 is fixedly arranged with the fourth plane 14 and the fifth plane 15 of the elastic element 1, and the fixing method can be welding, riveting, or threaded connection. The second end 42 of the force transmission member 4 passes through the through hole of the third plane 13 of the elastic element 1 and is located at the lower part of the third plane 13 of the elastic element 1.

[0074] Figure 4 , Figure 5 , Figure 6 The stress process of the structure Figure 2 , Figure 3 The principles are the same and will not be repeated here.

[0075] The structural diagram of another embodiment of the elastic element in the strain gauge pressure sensor assembly for a stylus provided in the present application can be found in Figure 7 .

[0076] according to Figure 7 The elastic element only has a first plane 11, a second plane 12, and a third plane 13.

[0077] The third plane 13 may or may not have holes.

[0078] During assembly and use, the end of the first plane 11 away from the second plane 12 and the end of the third plane 13 away from the second plane 12 are both fixed to the fixing member or the force transmission member. Figure 2 The force-bearing principle of the elastic elements shown is the same and will not be repeated here.

[0079] The structural diagram of another embodiment of the elastic element in the strain gauge pressure sensor assembly for a stylus provided in the present application can be found in Figure 8 .

[0080] according to Figure 7 One end of the first plane 11 of the elastic element away from the second plane 12 extends a distance toward the third plane 13 along a plane parallel to the second plane 12 to form a fourth plane 14, and one end of the third plane 13 away from the second plane 12 extends a distance toward the first plane 11 along a plane parallel to the second plane 12 to form a fifth plane 15.

[0081] The third plane 13 may or may not have a hole.

[0082] During assembly and use, the fourth plane 14 and the fifth plane 15 are both fixed to the fixing member or the force transmission member. Figure 3 The force-bearing principle of the elastic elements shown is the same and will not be repeated here.

[0083] The structural diagram of another embodiment of the elastic element in the strain gauge pressure sensor assembly for a stylus provided in the present application can be found in Fig. 9 .

[0084] according to Fig. 9 , the end of the first plane 11 of the elastic element away from the second plane 12 extends along a plane parallel to the second plane 12 toward the third plane 13 until it contacts the third plane 13, generating a fourth plane 14, and forming a closed square. Or the end of the third plane 13 away from the second plane 12 extends along a plane parallel to the second plane 12 toward the first plane 11, until it contacts the first plane 11, generating a fifth plane 15, and forming a closed square.

[0085] The third plane 13 may or may not have a hole.

[0086] During assembly and use, the fourth plane 14 or the fifth plane 15 is fixed to the fixing member or the force transmission member. Figure 2 The force-bearing principle of the elastic elements shown is the same and will not be repeated here.

[0087] The terms "first", "second", "third", "fourth", "fifth", etc. in the specification, claims and drawings of this application are used to distinguish similar objects, but not to describe a specific order or sequence, and it should be understood that the terms used in this way are interchangeable under appropriate circumstances.

[0088] The above description is only an illustrative specific implementation manner of the present application. Without departing from the concept and principle of the present application, equivalent changes and modifications in any field shall fall within the scope of protection of the present application.

Claims

1. A pressure sensor assembly for a stylus pen, characterized in that: It comprises an elastic element (1), a strain gauge (2), a fixing piece (3) and a force transmission piece (4); the strain gauge (2) is arranged on the elastic element (1), one side of the elastic element (1) is arranged on the fixing piece (3), and the other side is connected to the force transmission piece (4); The elastic element (1) comprises a first plane (11), a second plane (12), a third plane (13), a fourth plane (14) and a fifth plane (15); the first plane (11) and the third plane (13) are respectively and vertically fixedly arranged on the same side at two ends of the second plane (12); the fourth plane (14) is vertically fixedly arranged at the end of the first plane (11), and the fifth plane (15) is vertically fixedly arranged at the end of the third plane (13); A pen holder (5) is fixedly arranged on the outer side of the fixing member (3); The fourth plane (14) and the fifth plane (15) are both fixedly arranged on the fixing member (3) or the force transmission member (4); the strain gauge (2) is arranged on the first plane (11) or the third plane (13) of the elastic element (1); When the fourth plane (14) and the fifth plane (15) are both fixedly arranged on the fixing member (3), the force transmission member (4) is arranged on the inner side or the outer side of the second plane (12); The force transmission member (4) comprises a first end (41) and a second end (42); the second end (42) is fixedly arranged at the end of the first end (41) of the force transmission member; when the force transmission member (4) is on the inner side of the second plane (12), the second end of the force transmission member passes through the third plane (13); when the force transmission member (4) is on the outer side of the second plane (12), the second end of the force transmission member is located on the outer side of the third plane (13).

2. The pressure sensor assembly for a stylus pen according to claim 1, characterized in that: The fourth plane (14) and the fifth plane (15) are arranged to face or be opposite to each other.

3. The pressure sensor assembly for a stylus pen according to claim 1, characterized in that: When the fourth plane (14) and the fifth plane (15) are arranged facing each other, a gap is left between the fourth plane (14) and the fifth plane (15), or the fourth plane (14) and the fifth plane (15) are connected to form a plane, one end of which is fixedly connected to the first plane (11) or the third plane (13).

4. The pressure sensor assembly for a stylus pen according to claim 1, characterized in that: When the fourth plane (14) and the fifth plane (15) are both fixedly arranged on the force transmission member (4), the second end of the force transmission member of the force transmission member (4) passes through the third plane (13) or is located outside the third plane (13).

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