Multi-key switch and automobile

Abstract

The utility model provides a multi-key switch and an automobile. The multi-key switch is characterized in that a time-base chip assembly is connected with a switch assembly, and a control unit is electrically connected with the time-base chip assembly. As the switch assembly has multiple switch states, the time base chip assembly generates the transmission signal according to the current switch state of the switch assembly, and then the control unit is used for detecting the oscillation frequency and the duty ratio of the transmission signal to obtain the current switch state of the switch assembly. When the voltage difference between the two ends of the switch assembly is small, the interference signal has obvious influence on the voltage of the analog signal and has small influence on the duty ratio and the oscillation frequency in the digital signal. According to the mode, the on-off state of the switch assembly is detected by detecting the duty ratio and the oscillation frequency of the digital signal, the influence of interference signals can be effectively reduced, and then the accuracy of on-off state detection is improved.

Description

Technical Field

[0001] The utility model generally relates to the technical field of electronic circuit control, and particularly relates to a multi-button switch and an automobile. Background Art

[0002] At present, many of the existing switch devices have multiple button switches, and the multiple button switches may be located at different positions. During use, it is generally necessary to know the opening and closing states of the multiple button switches. The existing detection method is as follows: collect and transmit the current signals of the button switches. Since the resistances of different buttons are different, an MCU chip is mostly used to collect the button voltage division, and then by analyzing the current voltage division value, it is confirmed which button is pressed, that is, which button is in the closed state.

[0003] According to the current technological development direction, the resistance value of the future ECU will be designed to be smaller and smaller, and the voltage provided by the MCU chip for the ECU will also be lower and lower. This will result in a lower and lower voltage division value of the button in actual applications.

[0004] For the application of multiple buttons, such as 4 buttons, the resistances between different buttons are different. When the power supply voltage of the MCU chip is 5V, the voltage difference between the buttons with similar resistance values is 1.25V. When the power supply of the MCU chip is 3.3V, the voltage difference between the buttons with similar resistance values is 0.825V.

[0005] It can be seen from this that during long-distance transmission (such as the button switch of an automobile application is in the center console, while the control ECU is in the seat), the too low voltage difference is more likely to be affected by interference signals, resulting in a change in voltage during the transmission process. This leads to misjudgment when analyzing the voltage division value to determine which button is closed. Summary of the Utility Model

[0006] In view of the above defects or deficiencies in the prior art, it is desired to provide a multi-button switch and an automobile.

[0007] On the one hand, the utility model provides a multi-button switch, including:

[0008] A switch assembly, which has multiple switch states;

[0009] A time base chip assembly, which is electrically connected to the switch assembly and is used to generate a transmission signal according to the switch state of the switch assembly;

[0010] A control unit, which is electrically connected to the time base chip assembly and is used to receive the transmission signal and detect the switch state of the switch assembly according to the oscillation frequency and duty cycle of the transmission signal.

[0011] According to the technical solution provided by the utility model, the switch assembly includes:

[0012] A plurality of first switching resistors and a plurality of first key switches, and the plurality of first switching resistors and the plurality of first key switches are electrically connected;

[0013] The combination of the open state and the closed state of the plurality of first key switches changes the series-parallel relationship of the plurality of first switching resistors, and is used to switch multiple switching states of the switch assembly.

[0014] According to the technical solution provided by the present invention, the plurality of first switching resistors are connected in series, and one end of the formed branch is connected to a high level and the other end is grounded;

[0015] One end of each of the plurality of first key switches is electrically connected to a node between two adjacent first switching resistors respectively; the other end is electrically connected to the time base chip assembly.

[0016] According to the technical solution provided by the present invention, the switch assembly has a first node and a second node; a first switching resistor and a first key switch are connected in series to form a switch branch; the plurality of switch branches are connected in parallel between the first node and the second node; the resistance values of the plurality of first switching resistors are different;

[0017] The first node is used to connect to a high level; the second node is used to be grounded; different pins of the time base chip assembly are electrically connected to the first node and the second node respectively.

[0018] According to the technical solution provided by the present invention, the first node is electrically connected to the high level through a pull-up resistor; or the second node is grounded through a grounding branch.

[0019] According to the technical solution provided by the present invention, the grounding branch includes:

[0020] A grounding resistor and a grounding capacitor; one end of the grounding resistor is electrically connected to the second node, and the other end is electrically connected to the grounding capacitor; the other end of the grounding capacitor is grounded.

[0021] According to the technical solution provided by the present invention, the switch assembly includes:

[0022] A plurality of second key switches, the plurality of second key switches are connected in parallel and are electrically connected to the time base chip assembly;

[0023] The combination of the open state and the closed state of the plurality of second key switches is used to switch multiple switching states of the switch assembly.

[0024] According to the technical solution provided by the present invention, the nodes of the plurality of second key switches far from the time base chip assembly are electrically connected to a high level or grounded.

[0025] According to the technical solution provided by the present utility model, the time base chip assembly includes:

[0026] a triode and a time base chip, the time base chip is electrically connected to the switch assembly; the emitter of the triode is grounded, and the collector is electrically connected to the control unit.

[0027] On the other hand, the present utility model provides an automobile, including: an automobile body, on which a steering wheel and an automobile seat are installed;

[0028] a multi-button switch as described in any one of the above is installed on the steering wheel and / or the automobile seat.

[0029] The beneficial effect of the present utility model lies in:

[0030] During use, the time base chip assembly is connected to the switch assembly, and the control unit is electrically connected to the time base chip assembly. Since the switch assembly has multiple switch states, the present utility model uses the time base chip assembly to generate a transmission signal according to the resistance value of the current switch state of the switch assembly, and then uses the control unit to detect the oscillation frequency and duty cycle of the transmission signal, and compare them with the oscillation frequency and duty cycle in the known switch state in the database to obtain the current switch state of the switch assembly. When the voltage difference across the switch assembly is small, the interference signal has an obvious influence on the voltage of the analog signal, and has a small influence on the duty cycle and oscillation frequency in the digital signal. The above method can effectively reduce the influence of the interference signal by converting the signal into a digital signal and then detecting the duty cycle and oscillation frequency to detect the switch state of the switch assembly, thereby improving the detection accuracy. Description of the Drawings

[0031] By reading the detailed description of the non-restrictive embodiments with reference to the following drawings, other features, purposes and advantages of the present utility model will become more obvious:

[0032] Figure 1 is a schematic diagram of a multi-button switch;

[0033] Figure 2 is another schematic diagram of a multi-button switch;

[0034] Figure 3 is a schematic diagram of the circuit connection relationship in the first embodiment;

[0035] Figure 4 is a schematic diagram of the circuit connection relationship in the second embodiment;

[0036] Figure 5 is a schematic diagram of the circuit connection relationship in the third embodiment;

[0037] Figure 6Schematic diagram of circuit connection relationship in the fourth implementation manner;

[0038] Figure 7 Schematic diagram of circuit connection relationship in the fifth implementation manner;

[0039] Wherein: 1. Negative electrode pin; 2. Trigger pin; 3. Output pin; 4. Reset pin; 5. Control pin; 6. Threshold pin; 7. Discharge pin; 8. Positive electrode pin; 9. Control unit; 10. First switch resistor; 11. First push-button switch; 12. Grounding resistor; 13. Grounding capacitor; 14. Triode; 15. Timer chip; 16. First node; 17. Second node; 18. Third node; 19. MCU chip; 20. Second push-button switch; 21. Pull-up resistor. Specific implementation manners

[0040] The present utility model will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the relevant utility model, rather than limiting the utility model. Additionally, it should be noted that for the convenience of description, only the parts related to the utility model are shown in the drawings.

[0041] It should be noted that, without conflict, the embodiments in the present utility model and the features in the embodiments can be combined with each other. The present utility model will be described in detail below with reference to the drawings and embodiments.

[0042] Embodiment 1

[0043] Please refer to Figure 1-2 , the present utility model provides a multi-button switch, including:

[0044] A switch assembly, the switch assembly having multiple switch states;

[0045] A timer chip assembly, the timer chip assembly being electrically connected to the switch assembly for generating a transmission signal according to the switch state of the switch assembly;

[0046] A control unit 9, the control unit 9 being electrically connected to the timer chip assembly for receiving the transmission signal and detecting the switch state of the switch assembly according to the oscillation frequency and duty cycle of the transmission signal.

[0047] Specifically, the transmission signal is a square wave signal (PWM pulse signal). When the voltage difference across the switch assembly is small, the interference signal has an obvious influence on the voltage of the analog signal, but has a small influence on the duty cycle and oscillation frequency in the digital signal.

[0048] The above method converts the original analog signal into a digital signal by using a time-base chip component, and then uses the control unit 9 (ECU, Electronic Control Unit) to detect the duty cycle and oscillation frequency to detect the switching state of the switching component, which can effectively reduce the influence of interference signals and thus improve the detection accuracy.

[0049] After the control unit 9 collects the transmission signal, it detects and identifies the oscillation frequency and duty cycle of the square wave. Then, it compares them one by one with the oscillation frequency and duty cycle in various switching states stored in the database, and takes the switching state corresponding to the set of oscillation frequency and duty cycle with the smallest error as the current switching state of the switching component. Among them, detecting the oscillation frequency and duty cycle and comparing with the data in the database are the existing functions of the control unit 9.

[0050] Further, the switching component includes:

[0051] A plurality of first switching resistors 10 and a plurality of first key switches 11, and the plurality of first switching resistors 10 and the plurality of first key switches 11 are electrically connected;

[0052] The combination of the off state and the on state of the plurality of first key switches 11 changes the series-parallel relationship of the plurality of first switching resistors 10, and is used to switch various switching states of the switching component.

[0053] Further, the plurality of first switching resistors 10 are connected in series, and one end of the formed branch is connected to a high level and the other end is grounded;

[0054] One end of each of the plurality of first key switches 11 is electrically connected to the node between two adjacent first switching resistors 10; the other end is electrically connected to the time-base chip component.

[0055] In the first implementation manner, refer to Figure 3 : The connection method in which a plurality of first switching resistors 10 are connected in series and are respectively connected to the nodes between the first switching resistors 10 through the first key switches 11. During use, by controlling the opening and closing of different first key switches 11, the series-parallel relationship between the plurality of first switching resistors 10 can be changed, thereby changing the overall resistance and enabling the switching component to have different resistance values.

[0056] This implementation manner can enable the plurality of key switches to cooperate with each other, and thus the adjustable resistance value range of the switching component is wider.

[0057] Further, the switch assembly has a first node 16 and a second node 17; one of the first switch resistors 10 and a first push-button switch 11 are connected in series to form a switch branch; a plurality of the switch branches are connected in parallel between the first node 16 and the second node 17; the resistance values of the plurality of first switch resistors 10 are different;

[0058] The first node 16 is used to connect to a high level; the second node 17 is used to connect to ground; different pins of the time-base chip assembly are electrically connected to the first node 16 and the second node 17 respectively.

[0059] Specifically, different first push-button switches 11 being in a closed state is used to make the switch assembly have different resistance values. When the push-button switch is used, it switches between open and closed states under an external force, and the plurality of push-button switches are independently opened and closed with respect to each other.

[0060] Specifically, different first push-button switches 11 being in a closed state is used to change the total resistance of the switch assembly, thereby achieving the effect of having different voltage division values. When the push-button switch is used, it switches between open and closed states under an external force, and the plurality of push-button switches are independently opened and closed with respect to each other.

[0061] Specifically, since the switch assembly has a plurality of switch branches connected in parallel, each branch has a first switch resistor 10 and a first push-button switch 11. When there are more parallel switch branches, the overall resistance of the switch assembly decreases. If the total voltage of the entire circuit remains unchanged, the voltage division across the switch assembly will also decrease after the resistance decreases.

[0062] When transmitting as an analog signal, a lower voltage division will result in being more susceptible to interference signals.

[0063] One of the first push-button switches 11 is closed and the rest are kept open, which is a kind of switch state. Since the resistance values of the first switch resistors 10 in different switch branches are different, the switch assembly has multiple switch states.

[0064] Specifically, the MCU chip 19 confirms the state of the switch by detecting the input voltage division value, so Figure 3 the resistance values of the multiple first switch resistors 10 can be the same or different. And Figure 1 、 Figure 2 Figure 7 the resistance values of the multiple first switch resistors 10 are all different.

[0065] Further, in the fifth implementation manner, referring to Figure 7 : The first node 16 is electrically connected to the high level through a pull-up resistor 21.

[0066] Further, referring to Figure 2 , the second node 17 is grounded through a grounding branch.

[0067] The grounding branch includes:

[0068] a grounding resistor 12 and a grounding capacitor 13; one end of the grounding resistor 12 is electrically connected to the second node 17, and the other end is electrically connected to the grounding capacitor 13; the other end of the grounding capacitor 13 is grounded.

[0069] Specifically, a resistor and a capacitor are connected on the grounding branch. The power supply passes through the first switching resistor 10, and the grounding resistor 12 charges the series-connected grounding capacitor 13. Different values of the first switching resistor 10 will result in different charging times of the grounding capacitor 13, so that the oscillation frequency / duty cycle output by the time base chip 15 is different, and different oscillation frequencies / duty cycles correspond to different switching states.

[0070] Reference Figures 3-7 , which are multiple implementation manners of the circuit structure of the key switch provided by the present invention.

[0071] Among them, VDD represents the power supply voltage of a unipolar device, generally called high level. ADC is an analog-to-digital conversion interface, GPIO represents a general-purpose input / output interface, and GND represents grounding. The symbol above the collector of the right triode indicates the generation of a square wave signal. SW1, SW2 to SWn represent multiple second key switches 20, and the MCU chip represents a micro control unit (Micro control l er Unit). Figures 3-7 The collector of the triode in [] is connected to the control unit 9, that is, the ECU.

[0072] Figures 4-6 The MCU chip 19 in [] needs to be programmed separately before use to adapt to specific application scenarios; the ultimate effect achieved is to convert the signal of the key switch into a square wave signal, and then judge the state of the switch component according to the duty cycle and oscillation frequency.

[0073] Figure 7 The pull-up resistor 21 in [] is connected to VDD. The pull-up resistor 21 cooperates with the first switching resistor 10 with different resistance values to obtain different voltage division values. After being analyzed by the MCU chip 19, the MCU chip 19 outputs different oscillation frequencies / duty cycles, and different oscillation frequencies / duty cycles correspond to different switching states.

[0074] Further, the switch component includes:

[0075] multiple second key switches 20, which are connected in parallel with each other and are electrically connected to the time base chip assembly;

[0076] The combination of the open state and the closed state of the multiple second key switches 20 is used to switch multiple switching states of the switch component.

[0077] Further, referring to Figures 4-5 , which is a schematic diagram of the circuit connection relationship in the second and third implementation manners. Multiple nodes of the second button switches 20 away from the time base chip assembly are electrically connected to a high level or grounded.

[0078] Referring to Figure 6 , which is a schematic diagram of the circuit connection relationship in the fourth implementation manner. Through the on-off state combinations of multiple second button switches 20, after different switch combinations are analyzed by the MCU chip 19, the MCU chip 19 outputs different oscillation frequencies / duty cycles, and different oscillation frequencies / duty cycles correspond to different switch states.

[0079] Further, the time base chip assembly includes:

[0080] A triode 14 and a time base chip 15, the time base chip 15 is electrically connected to the switch assembly; the emitter of the triode 14 is grounded, and the collector is electrically connected to the control unit 9.

[0081] In some implementation manners, the function of the triode 14 is signal isolation and amplification, which is used to amplify the weak signal output by the MCU chip 19, and at the same time, it can also prevent the voltage outside the switch from impacting the MCU chip 19 and causing adverse effects.

[0082] In some implementation manners, there is a third node 18 between the grounding resistor 12 and the grounding capacitor 13;

[0083] The time base chip 15 is an NE555 type chip, including: a negative electrode pin 1, a trigger pin 2, an output pin 3, a reset pin 4, a control pin 5, a threshold pin 6, a discharge pin 7, and a positive electrode pin 8;

[0084] The negative electrode pin 1 is grounded;

[0085] Both the trigger pin 2 and the threshold pin 6 are electrically connected to the third node 18;

[0086] The output pin 3 is electrically connected to the base of the triode 14;

[0087] Both the reset pin 4 and the positive electrode pin 8 are electrically connected to the first node 16;

[0088] The control pin 5 is left unconnected;

[0089] The discharge pin 7 is electrically connected to the second node 17.

[0090] Further, the time base chip 15 is an MCU chip 19, a CD4541 type chip or a 74HC123 type chip. In another implementation manner, an oscillation chip can also be used.

[0091] Specifically, the function of the time base chip 15 is to generate a time reference pulse signal. The time base chip is a general term, which can be a dedicated chip, such as the NE555 type, or other chips with the same function, or a single-chip microcomputer, the MCU chip 19, and the time base function is completed through software programming.

[0092] The working principle of the NE555 type chip belongs to the prior art and will not be elaborated. The function of the NE555 type chip to work is based on the construction of a timing circuit. Changing the resistance value connected to it can control the oscillation frequency and duty cycle to achieve the generation of various pulse waveforms. In the present utility model, in different switch states of the switch assembly, the resistance values connected to the NE555 type chip are different, thereby achieving the effect of using the NE555 type chip to adjust the oscillation frequency and duty cycle.

[0093] Reference Figure 1 , R1 to R4 are respectively the first switch resistors 10 in different switch branches, S1 to S4 are respectively the first key switches 11 in different switch branches, VCC represents the power supply voltage of a bipolar device, generally also called the high level, but in this embodiment, it is different from the VDD voltage value, GND represents grounding, C represents the grounding capacitor 13, R0 represents the grounding resistor 12, and T represents the triode 14.

[0094] Embodiment 2

[0095] The present utility model also provides an automobile, including:

[0096] An automobile body, on which a steering wheel and an automobile seat are installed;

[0097] One of the multi-key switches as described in any one of the above embodiments is installed on the steering wheel and / or the automobile seat.

[0098] Specifically, the above key switch can also be installed on the steering wheel and the automobile seat of the automobile body to achieve multiple functions. The key switch in the above embodiment can accurately detect the opening and closing states to monitor the conditions of the steering wheel and the automobile seat on the automobile body.

[0099] The above description is only the preferred embodiment of the present utility model and the explanation of the applied technical principle. Those skilled in the art should understand that the scope of the utility model involved in the present utility model is not limited to the technical solution formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept of the present utility model. For example, the technical solutions formed by mutually replacing the above features with the technical features (but not limited to) having similar functions disclosed in the present utility model.

Claims

1. A multi-button switch, characterized in that: include: A switch assembly, wherein the switch assembly has multiple switch states; A time base chip component, the time base chip component is electrically connected to the switch component and is used to generate a transmission signal according to the switch state of the switch component; A control unit (9), the control unit (9) is electrically connected to the time base chip component, and is used to receive the transmission signal, and detect the switch state of the switch component according to the oscillation frequency and duty cycle of the transmission signal.

2. A multi-button switch according to claim 1, characterized in that: The switch assembly comprises: A plurality of first switch resistors (10) and a plurality of first key switches (11), wherein the plurality of first switch resistors (10) and the plurality of first key switches (11) are electrically connected; The combination of the open state and the closed state of the plurality of first key switches (11) changes the series-parallel relationship of the plurality of first switch resistors (10) and is used to switch the plurality of switch states of the switch assembly.

3. A multi-button switch according to claim 2, characterized in that: A plurality of the first switch resistors (10) are connected in series, and one end of the formed branch is connected to a high level and the other end is grounded; One end of each of the plurality of first key switches (11) is electrically connected to a node between two adjacent first switch resistors (10); and the other end is electrically connected to the time base chip assembly.

4. A multi-button switch according to claim 2, characterized in that: The switch component has a first node (16) and a second node (17); a first switch resistor (10) and a first key switch (11) are connected in series to form a switch branch; a plurality of switch branches are connected in parallel between the first node (16) and the second node (17); the resistance values ​​of the plurality of first switch resistors (10) are different; The first node (16) is used to connect a high level; the second node (17) is used to be grounded; and different pins of the timing chip component are electrically connected to the first node (16) and the second node (17) respectively.

5. A multi-button switch according to claim 4, characterized in that: The first node (16) is electrically connected to the high level by connecting to a pull-up resistor (21); or the second node (17) is grounded by connecting to a grounding branch.

6. A multi-button switch according to claim 5, characterized in that: The grounding branch comprises: A grounding resistor (12) and a grounding capacitor (13); one end of the grounding resistor (12) is electrically connected to the second node (17), and the other end is electrically connected to the grounding capacitor (13); the other end of the grounding capacitor (13) is grounded.

7. The multi-button switch according to claim 1, characterized in that: The switch assembly comprises: A plurality of second key switches (20), wherein the plurality of second key switches (20) are connected in parallel and are electrically connected to the time base chip assembly; The combination of the open state and the closed state of the plurality of second key switches (20) is used to switch the plurality of switch states of the switch assembly.

8. A multi-button switch according to claim 7, characterized in that: Nodes of the plurality of second key switches (20) away from the time base chip assembly are electrically connected to a high level or to ground.

9. The multi-button switch according to claim 1, characterized in that: The time base chip assembly comprises: A triode (14) and a time base chip (15), wherein the time base chip (15) is electrically connected to the switch component; the emitter of the triode (14) is grounded, and the collector is electrically connected to the control unit (9).

10. An automobile, characterized in that: include: A car body, on which a steering wheel and a car seat are installed; The steering wheel and / or the car seat is / are installed with a multi-button switch as described in any one of claims 1-9.

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