CN-121979403-A - Knob and sensing circuit thereof

Abstract

The invention discloses a knob and a sensing circuit, wherein the knob is arranged on a touch screen, and the touch screen comprises a first touch sensing unit, a second touch sensing unit and a third touch sensing unit. The knob includes a bottom surface and a first connecting portion. The bottom surface comprises a sensing electrode aligned with the first touch sensing unit, a first common electrode aligned with the second touch sensing unit and receiving a first reference voltage from the second touch sensing unit, and a second common electrode aligned with the third touch sensing unit and receiving a second reference voltage from the third touch sensing unit. When the knob rotates, the first connecting part is used for controlling whether the sensing electrode is conducted with the first common electrode and the second common electrode. A touch sensing circuit of the touch screen judges the rotation direction of the knob according to the signal variation of the first touch sensing unit.

Inventors

• Cai Wuchuan

Assignees

• 联咏科技股份有限公司

Dates

Publication Date

20260505

Application Date

20241030

Claims (18)

1. 1. The utility model provides a knob, sets up in a touch-sensitive screen, its characterized in that, this touch-sensitive screen includes a first touch-control sensing unit, a second touch-control sensing unit and a third touch-control sensing unit, and this knob includes: A bottom surface, comprising: A sensing electrode aligned with the first touch sensing unit; A first common electrode aligned with the second touch sensing unit for receiving a first reference voltage from the second touch sensing unit, and A second common electrode aligned with the third touch sensing unit for receiving the second reference voltage from the third touch sensing unit, and A first connection part for controlling whether the sensing electrode is conducted with the first common electrode and the second common electrode when the knob is rotated; the touch sensing circuit of the touch screen judges the rotating direction of the knob according to the signal variation of the first touch sensing unit.
2. 2. The knob according to claim 1, wherein the first common electrode or the second common electrode further receives a third reference voltage from a touch object operating the knob to form the signal variation in the first touch sensing unit.
3. 3. The knob according to claim 2, further comprising: and a conductor coupled to the first common electrode or the second common electrode for receiving the third reference voltage from the touch object when the touch object operates the knob.
4. 4. The knob of claim 1 wherein the first common electrode and the second common electrode are of different sizes.
5. 5. The knob according to claim 1, wherein the bottom surface further comprises a third common electrode electrically connected to the sensing electrode when the knob is pressed and not electrically connected to the sensing electrode when the knob is not pressed.
6. 6. The knob according to claim 5, further comprising: And the second connecting part is used for controlling whether the sensing electrode and the third electrode are conducted or not when the knob is pressed.
7. 7. The knob of claim 1 wherein the knob comprises only a single sensing electrode.
8. 8. The knob according to claim 1, wherein at least one of the first reference voltage and the second reference voltage is a ground voltage.
9. 9. The knob according to claim 1, wherein the first common electrode is coupled to a common electrode ring, and the sensing electrode is coupled to a sensing electrode ring, wherein a connecting post is disposed on the sensing electrode ring, and the connecting post is electrically connected to the sensing electrode ring.
10. 10. The knob of claim 9 wherein the common electrode ring contacts the connecting post and is electrically connected to the sensing electrode ring when the knob is rotated to a first angle, and wherein the common electrode ring does not contact the connecting post when the knob is rotated to a second angle.
11. 11. The knob of claim 9 wherein the sensing electrode ring is fixed to the touch screen and the common electrode ring rotates with the knob when the knob is rotated.
12. 12. The knob of claim 9 wherein the common electrode ring is fixed to the touch screen and the sense electrode ring rotates with the knob when the knob is rotated.
13. 13. A sensing circuit coupled to a knob, the sensing circuit comprising: A receiving circuit for receiving a signal variation from the knob, and The processing circuit is coupled with the receiving circuit and used for judging the rotation direction of the knob according to the signal variation; the signal variation is received by a first touch sensing unit aligned with and coupled to a sensing electrode of the knob; the signal variation is generated according to whether the sensing electrode is conducted with a first common electrode and a second common electrode in the knob.
14. 14. The sensing circuit of claim 13, wherein the knob comprises only a single one of the sense electrodes.
15. 15. The sensing circuit of claim 13, wherein a second touch sensing unit corresponding to the first common electrode and a third touch sensing unit corresponding to the second common electrode are respectively applied with a first reference voltage and a second reference voltage to generate the signal variation.
16. 16. The sensing circuit of claim 15, wherein at least one of the first reference voltage and the second reference voltage is a ground voltage.
17. 17. The sensing circuit of claim 15, wherein at least one of the first reference voltage and the second reference voltage is derived from a touch object operating the knob.
18. 18. The sensing circuit of claim 13, wherein the processing circuit further determines whether the knob is pressed based on the signal change.

Description

Knob and sensing circuit thereof Technical Field The present invention relates to a knob sensing technology, and more particularly, to a knob sensing technology for a touch screen. Background Touch control functions are becoming popular in central information display (Center Information Display, CID) systems of vehicles, and when the environmental settings of the vehicle (such as the air-conditioning temperature and the volume of the car audio) need to be adjusted, the driver must pay more attention to the relevant settings displayed on the touch control position and screen, thus affecting the driving safety. In order to improve driving safety, a knob on a touch screen is used in the central information display system, and a physical knob is arranged on the touch screen, so that a driver can easily adjust the setting by means of the control knob without watching the displayed numerical value in a distracting way. Disclosure of Invention The main objective of the present invention is to provide a knob on a touch screen and a related sensing circuit thereof. An embodiment of the invention discloses a knob which is arranged on a touch screen. The touch screen comprises a first touch sensing unit, a second touch sensing unit and a third touch sensing unit. The knob includes a bottom surface and a first connection portion. The bottom surface comprises a sensing electrode aligned with the first touch sensing unit, a first common electrode aligned with the second touch sensing unit and receiving a first reference voltage from the second touch sensing unit, and a second common electrode aligned with the third touch sensing unit and receiving a second reference voltage from the third touch sensing unit. When the knob rotates, the first connecting part is used for controlling whether the sensing electrode is conducted with the first common electrode and the second common electrode. A touch sensing circuit of the touch screen judges the rotating direction of the knob according to the signal variation of the first touch sensing unit. Another embodiment of the present invention discloses a sensing circuit coupled to a knob. The sensing circuit comprises a receiving circuit and a processing circuit. The receiving circuit is used for receiving a signal variation from the knob. The processing circuit is coupled to the receiving circuit and used for judging the rotation direction of the knob according to the signal variation. The signal variation is received by a first touch sensing unit aligned with and coupled to a sensing electrode of the knob, and the signal variation is generated according to whether the sensing electrode is conducted with a first common electrode and a second common electrode in the knob. Drawings Fig. 1 is a schematic bottom view of a knob. Fig. 2 is a schematic view of another knob. FIG. 3 is a schematic view of a knob according to an embodiment of the present invention. Fig. 4 shows in a disassembled manner the detailed structure of the electrode rings of the sensing electrode and the common electrode. Fig. 5 and 6 show side views of the electrode ring configuration in the knob of fig. 3. FIG. 7 is a schematic view of another knob according to an embodiment of the present invention. Fig. 8 shows in a disassembled manner the detailed structure of the electrode rings of the sensing electrode and the common electrode. Fig. 9 and 10 show side views of the electrode ring configuration in the knob of fig. 7. Fig. 11A to 11D respectively show the sensing system in which the knob is in 4 different states. Fig. 12 shows the correspondence between the equivalent capacitance value and the sensing signal. Fig. 13 shows a schematic view of the rotation operation of the knob corresponding to different states. Fig. 14 shows a schematic view of the pressing operation of the knob corresponding to different states. FIG. 15 shows that the knob status is determined according to the corresponding relationship between the equivalent capacitance value and the sensing signal and the threshold value. FIG. 16 is a schematic diagram showing signal distribution of a touch sensing unit corresponding to a sensing electrode according to an embodiment of the invention FIG. 17 is a schematic view of a conductor of a knob according to an embodiment of the invention. Wherein reference numerals are as follows: 10. 20, 30, 70, 170 knob RA, RB, RX sensing electrode Angle of theta rotation COM, COM1, COM2, COM3 common electrode 300. 700 Touch screen S1-S4 touch sensing unit 402. Sensing electrode ring 404. 414, 424, 804 Electrode columns 406. 408, 806_1, 806_2, 806_3 Connecting column 412. 422, 802 Common electrode ring 806. Connecting part 900. Pressing spring piece 110. Sensing system 1100. Sensing circuit 1102. Receiving circuit 1104. Processing circuit VRX sense signal 0C, 1C, 2C, 3C state TH1 to TH3 threshold 1700. Metal layer 1702. Rubber layer 1704. Shell body Detailed Description Fig. 1 is a schematic bottom view of a knob 10. A