Gear detection circuit and air duct

Abstract

The utility model discloses a gear detection circuit and an air duct, the gear detection circuit is connected with a detection end, the gear detection circuit comprises a slide switch, a plurality of voltage input circuits and a divider resistor; the input end of the voltage input circuit is connected with any gear line of the slide switch and is used for parallel connection according to conduction of the slide switch; one end of the divider resistor is respectively connected with the output end and the detection end of the voltage input circuit, and the other end of the divider resistor is grounded; and the divider resistor is used for carrying out voltage division with the voltage input circuit and outputting a voltage division signal to the detection end. According to the utility model, the voltage input circuit is connected in parallel according to the conduction of the slide switch, and the voltage dividing resistor is used for dividing the voltage, so that the gear identification is realized according to the divided voltage, the optocoupler detection is not needed, and the cost and the occupied space are further reduced.

Description

Technical Field

[0001] The utility model relates to the field of detection technology, in particular to a gear position detection circuit and a hair dryer. Background Art

[0002] The current high-speed hair dryer power switch is designed to withstand high voltage. The high-voltage switch has three gears. The first gear is turned on to connect the AC power to the hair dryer for the 1st wind speed, the second gear is the 2nd wind speed, and the third gear is the 3rd wind speed. The current gear switching uses an optocoupler to identify the gear switching. The 2nd and 3rd wind speeds require two optocoupler detection circuits. However, the two optocoupler detection circuits not only increase the cost, but also occupy the limited internal space of the hair dryer.

[0003] Therefore, the prior art still needs to be improved and developed. Utility Model Content

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a gear position detection circuit and a hair dryer to solve the problems of high cost and large space occupied by the gear position detection circuit in the prior art.

[0005] The technical solution of the utility model is as follows:

[0006] A gear position detection circuit is connected to the detection end, and the gear position detection circuit includes: a sliding switch, a plurality of voltage input circuits and a voltage dividing resistor;

[0007] The input end of the voltage input circuit is connected to any gear position line of the sliding switch, and is used for parallel connection according to the conduction of the sliding switch;

[0008] One end of the voltage-dividing resistor is connected to the output end and the detection end of the voltage input circuit respectively, and the other end of the voltage-dividing resistor is grounded;

[0009] The voltage-dividing resistor is used to divide the voltage with the voltage input circuit, and output the voltage-dividing signal to the detection end.

[0010] In a further configuration of the utility model, the voltage input circuit includes a rectifier bridge unit;

[0011] The positive and negative terminals of the rectifier bridge unit are connected to a DC power supply, and the two AC terminals of the rectifier bridge unit are connected to an AC power supply and the slide switch respectively.

[0012] In a further configuration of the utility model, the voltage input circuit includes a first resistor and a second resistor;

[0013] One end of the first resistor is connected to the slide switch, the other end of the first resistor is connected to one end of the second resistor, and one end of the second resistor is connected to the voltage-dividing resistor.

[0014] In a further configuration of the utility model, the voltage input circuit includes a third resistor and a resistor-capacitor;

[0015] One end of the third resistor is connected to the slide switch, the other end of the third resistor is connected to one end of the resistor-capacitor capacitor, and the other end of the resistor-capacitor capacitor is connected to the voltage-dividing resistor.

[0016] A further configuration of the utility model further includes a rectifier unit;

[0017] The rectifying unit is connected to the voltage-dividing resistor and is used for rectifying the voltage-dividing signal.

[0018] A further configuration of the utility model further includes a filtering unit;

[0019] The filtering unit is connected to the rectifying unit and is used for filtering the rectified divided voltage signal.

[0020] In a further configuration of the utility model, the rectifying unit includes a diode;

[0021] The anode of the diode is connected to the voltage-dividing resistor, and the cathode of the diode is connected to the filtering unit.

[0022] In a further configuration of the utility model, the filtering unit includes a fourth resistor, a first capacitor and a second capacitor;

[0023] One end of the first capacitor is connected to the rectifier unit and one end of the fourth resistor respectively, and the other end of the first capacitor is grounded; the other end of the fourth resistor is connected to one end of the second capacitor and the detection end respectively, and the other end of the second capacitor is grounded.

[0024] In a further configuration of the utility model, the filtering unit further includes a fifth resistor;

[0025] The fifth resistor is connected to the other end of the fourth resistor, and the other end of the fifth resistor is grounded.

[0026] The utility model also provides a hair dryer, comprising the gear position detection circuit as described above.

[0027] The utility model provides a gear detection circuit and a hair dryer, which are connected to the detection end, and the gear detection circuit includes: a sliding switch, a plurality of voltage input circuits and a voltage-dividing resistor; the input end of the voltage input circuit is connected to any gear line of the sliding switch, and is used for parallel connection according to the conduction of the sliding switch; one end of the voltage-dividing resistor is respectively connected to the output end and the detection end of the voltage input circuit, and the other end of the voltage-dividing resistor is grounded; the voltage-dividing resistor is used for voltage division with the voltage input circuit, and outputs the voltage-dividing signal to the detection end. The utility model uses the voltage input circuit to be connected in parallel according to the conduction of the sliding switch, and divides the voltage through the voltage-dividing resistor, so as to realize gear recognition according to the voltage-dividing voltage, without the need for optical coupling detection, and further reduces the cost and occupied space. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary personnel in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0029] Figure 1 It is a structural principle diagram of the mid-range position detection circuit of the utility model.

[0030] Figure 2 It is a schematic diagram of the conduction of the sliding switch in the utility model.

[0031] Figure 3 The utility model is a circuit diagram of a mid-range position detection circuit.

[0032] The symbols in the accompanying drawings are: 100, voltage input circuit; AC, alternating current power supply; P1, detection terminal; RX, voltage dividing resistor; R1, first resistor; R2, second resistor; R4, fourth resistor; R5, fifth resistor;

[0033] C1, first capacitor; C2, second capacitor; VD, diode; 200, rectifier unit; 300, filter unit; U1, rectifier bridge unit; B, DC power supply; N, live wire; L, neutral wire. DETAILED DESCRIPTION

[0034] The utility model provides a gear detection circuit and a hair dryer. In order to make the purpose, technical solution and effect of the utility model clearer and more specific, the utility model is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not used to limit the utility model.

[0035] In the embodiments and patent claims, unless the article is specifically limited in the text, "a", "an", "said" and "the" may also include plural forms. If there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0036] It should be further understood that the term "comprising" used in the specification of the present utility model refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there can also be intermediate elements. In addition, the "connection" or "coupling" used here can include wireless connection or wireless coupling. The term "and / or" used here includes all or any unit and all combinations of one or more associated listed items.

[0037] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of ordinary technicians in the field to which the utility model belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as the meaning in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0038] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0039] Please also see Figures 1 to 3 The utility model provides a preferred embodiment of a gear position detection circuit.

[0040] like Figure 1As shown, the gear detection circuit in the utility model is connected to the detection terminal P1, and the gear detection circuit includes: a sliding switch K1, a plurality of voltage input circuits 100 and a voltage dividing resistor RX; the input end of the voltage input circuit 100 is connected to any gear line of the sliding switch K1, and is used for parallel connection according to the conduction of the sliding switch K1; one end of the voltage dividing resistor RX is respectively connected to the output end of the voltage input circuit 100 and the detection terminal P1, and the other end of the voltage dividing resistor RX is grounded; the voltage dividing resistor RX is used to divide the voltage with the voltage input circuit 100, and output the divided voltage signal to the detection terminal P1.

[0041] Specifically, the slide switch K1 has a single input and multiple outputs. Figure 2 FIG. 2 is a schematic diagram showing the conduction state of the sliding switch K1. Figure 2 As shown, when the sliding switch K1 slides to position 1, the sliding switch K1 is in a neutral state in the circuit. When the sliding switch K1 slides to position 2, the sliding switch K1 connects the input end with the output end 3. When the sliding switch K1 slides to position 3, the input end of the sliding switch K1 is connected to both the output end 2 and the output end 3. Figure 1 As shown, the input end of the sliding switch K1 is connected to the AC power supply AC, and the input end of the voltage input circuit 100 is connected to any gear line of the sliding switch. When the sliding switch K1 slides, two or more voltage input circuits 100 will be connected in parallel. The voltage-dividing resistor RX will divide the voltage with the voltage input circuit 100, and output the voltage-dividing signal to the detection terminal P1, and the detection terminal P1 will identify the gear according to the voltage of the voltage-dividing signal. It can be understood that different gears will have different numbers of voltage input circuits 100 connected in parallel, so the detection voltage of the voltage-dividing signal obtained by the detection terminal P1 will be different, so that the gear recognition is realized by identifying the voltage, without the need for optical coupling detection, further reducing costs and occupied space.

[0042] In one embodiment, if Figure 3 As shown, the voltage input circuit 100 includes a rectifier bridge unit U1; the positive and negative terminals of the rectifier bridge unit U1 are connected to a DC power supply B, and the two AC terminals of the rectifier bridge unit U1 are respectively connected to an AC power supply AC and the slide switch K1.

[0043] The voltage input circuit 100 further includes a first resistor R1 and a second resistor R2; one end of the first resistor R1 is connected to the slide switch K1, the other end of the first resistor R1 is connected to one end of the second resistor R2, and one end of the second resistor R2 is connected to the voltage divider resistor RX.

[0044] Specifically, the positive terminal of the rectifier bridge unit U1 is connected to the positive electrode of the DC power supply B, the negative terminal of the rectifier bridge unit U1 is connected to the negative electrode of the DC power supply B, one AC terminal of the rectifier bridge unit U1 is connected to the neutral line L, the other AC terminal of the rectifier bridge unit U1 is connected to the output end of the slide switch K1, and the input end of the slide switch K1 is connected to the live line N. In this embodiment, one of the voltage input circuits 100 is the rectifier bridge unit U1, and the other voltage input circuit 100 is two resistors connected in series, wherein, if the slide switch K1 only turns on the voltage input circuit 100 where the rectifier bridge unit U1 is located, the entire circuit system is turned on, and the detection terminal P1 outputs a voltage of 0V. If the sliding switch K1 not only turns on the voltage input circuit 100 where the rectifier bridge unit U1 is located, but also turns on the voltage input circuit 100 with two resistors in series, the rectifier bridge unit U1 will provide a DC bias for the first resistor R1 and the second resistor R2, and the detection terminal P1 detects the voltage division of the series resistor (the resistor in series with the first resistor R1 and the second voltage) and the voltage division voltage. Similarly, if the third voltage input circuit 100 also uses resistors in series, the detection terminal P1 detects the voltage division of the parallel resistor (two series resistors in parallel) and the voltage division resistor RX. In this way, gear position recognition is achieved by detecting voltage.

[0045] In one embodiment, the voltage input circuit 100 includes a rectifier bridge unit U1; the positive and negative terminals of the rectifier bridge unit U1 are connected to a DC power supply B, and the two AC terminals of the rectifier bridge unit U1 are respectively connected to an AC power supply AC and the slide switch K1.

[0046] The voltage input circuit 100 includes a third resistor and a resistor-capacitor (RC) (not shown in the figure); one end of the third resistor is connected to the sliding switch K1, the other end of the third resistor is connected to one end of the RC capacitor, and the other end of the RC capacitor is connected to the voltage dividing resistor RX.

[0047] Specifically, when the sliding switch K1 only turns on the voltage input circuit 100 where the rectifier bridge unit U1 is located, the entire circuit system is turned on, and the detection terminal P1 outputs a voltage of 0V. If the sliding switch K1 not only turns on the voltage input circuit 100 where the rectifier bridge unit U1 is located, but also turns on the voltage input circuit 100 including the resistor and the capacitor, the detection terminal P1 detects the voltage divided by the resistor-capacitor step-down circuit (the impedance formed by the third resistor and the resistor-capacitor capacitor in series) and the divided voltage. In this way, gear position identification is achieved by detecting voltage. Among them, the resistor-capacitor capacitor is used to limit the current and achieve the purpose of voltage reduction.

[0048] In one embodiment, if Figure 3As shown, the gear detection circuit further includes a rectifier unit 200, and the rectifier unit 200 is connected to the voltage-dividing resistor RX for rectifying the voltage-dividing signal.

[0049] Specifically, after the voltage-dividing resistor RX divides the voltage, it outputs a voltage-dividing signal to the detection terminal P1, so that the detection terminal P1 can identify the gear position according to the detection voltage. The rectifier unit 200 is provided between the voltage-dividing resistor RX and the detection terminal P1 to rectify the voltage-dividing signal and provide a smooth direct current for the detection terminal P1.

[0050] In one embodiment, if Figure 3 As shown, the gear detection circuit further includes a filtering unit 300, and the filtering unit 300 is connected to the rectifying unit 200, and is used for filtering the rectified divided voltage signal.

[0051] Specifically, the filtering unit 300 is provided between the rectifying unit 200 and the detecting terminal P1 to filter the rectified divided voltage signal to remove clutter and harmonics in the signal, thereby providing a stable divided voltage signal for the detecting terminal P1 and improving detection accuracy.

[0052] In one embodiment, if Figure 3 As shown, the rectifying unit 200 includes a diode VD; the anode of the diode VD is connected to the voltage-dividing resistor RX, and the cathode of the diode VD is connected to the filtering unit 300 .

[0053] Specifically, the rectifying unit 200 is a diode VD, which removes the AC component in the voltage-dividing signal by utilizing the single-phase conductivity of the diode VD, so as to provide a smooth DC signal for subsequent circuits.

[0054] In one such embodiment, Figure 3 As shown, the filtering unit 300 includes a fourth resistor R4, a first capacitor C1 and a second capacitor C2; one end of the first capacitor C1 is respectively connected to the rectifying unit 200 and one end of the fourth resistor R4, and the other end of the first capacitor C1 is grounded; the other end of the fourth resistor R4 is respectively connected to one end of the second capacitor C2 and the detection end P1, and the other end of the second capacitor C2 is grounded.

[0055] Specifically, in this embodiment, the filtering unit 300 adopts a CRCπ-type filtering network. The rectified output voltage is first filtered by the first capacitor C1 to remove most of the AC components. The voltage after passing through the first capacitor C1 is then added to the RC filtering circuit composed of the fourth resistor R4 and the second capacitor C2. The second capacitor C2 further filters the AC components to improve the filtering capability of the divided voltage signal.

[0056] In one embodiment, if Figure 3 As shown, the filtering unit 300 further includes a fifth resistor R5; the fifth resistor R5 is connected to the other end of the fourth resistor R4, and the other end of the fifth resistor R5 is grounded.

[0057] Specifically, in this embodiment, the fourth resistor R4 not only performs filtering in combination with the second capacitor C2, but also performs DC voltage division in combination with the fifth resistor R5 to prevent the voltage input to the detection terminal P1 from being too large, causing the detection terminal P1 to be over-voltage and damaged. At the same time, the resistance value of the fifth resistor R5 can also control the charging and discharging time of the first capacitor C1 to further control the filtering degree.

[0058] The utility model also provides a hair dryer, comprising the gear position detection circuit as described above, which is described in detail in an embodiment of the gear position detection circuit and will not be described in detail here.

[0059] In summary, the utility model provides a gear detection circuit and a hair dryer, which are connected to the detection end, and the gear detection circuit includes: a sliding switch, a plurality of voltage input circuits and a voltage-dividing resistor; the input end of the voltage input circuit is connected to any gear line of the sliding switch, and is used for parallel connection according to the conduction of the sliding switch; one end of the voltage-dividing resistor is respectively connected to the output end and the detection end of the voltage input circuit, and the other end of the voltage-dividing resistor is grounded; the voltage-dividing resistor is used to divide the voltage with the voltage input circuit, and output the voltage-dividing signal to the detection end. The utility model uses the voltage input circuit to be connected in parallel according to the conduction of the sliding switch, and divides the voltage through the voltage-dividing resistor, so as to realize gear recognition according to the divided voltage, without the need for optical coupling detection, and further reduces the cost and occupied space.

[0060] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made according to the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A gear position detection circuit, connected to a detection terminal, characterized in that: include: Slide switch, several voltage input circuits and voltage dividing resistors; The input end of the voltage input circuit is connected to any gear position line of the sliding switch, and is used for parallel connection according to the conduction of the sliding switch; One end of the voltage-dividing resistor is connected to the output end and the detection end of the voltage input circuit respectively, and the other end of the voltage-dividing resistor is grounded; The voltage-dividing resistor is used to divide the voltage with the voltage input circuit, and output the voltage-dividing signal to the detection end.

2. The gear position detection circuit according to claim 1, characterized in that: The voltage input circuit includes a rectifier bridge unit; The positive and negative terminals of the rectifier bridge unit are connected to a DC power supply, and the two AC terminals of the rectifier bridge unit are connected to an AC power supply and the slide switch respectively.

3. The gear position detection circuit according to claim 2, characterized in that: The voltage input circuit includes a first resistor and a second resistor; One end of the first resistor is connected to the slide switch, the other end of the first resistor is connected to one end of the second resistor, and one end of the second resistor is connected to the voltage-dividing resistor.

4. The gear position detection circuit according to claim 2, characterized in that: The voltage input circuit includes a third resistor and a resistor-capacitor; One end of the third resistor is connected to the slide switch, the other end of the third resistor is connected to one end of the resistor-capacitor capacitor, and the other end of the resistor-capacitor capacitor is connected to the voltage-dividing resistor.

5. The gear position detection circuit according to claim 1, characterized in that: Also includes a rectifier unit; The rectifying unit is connected to the voltage-dividing resistor and is used for rectifying the voltage-dividing signal.

6. The gear position detection circuit according to claim 5, characterized in that: Also includes a filtering unit; The filtering unit is connected to the rectifying unit and is used for filtering the rectified divided voltage signal.

7. The gear position detection circuit according to claim 6, characterized in that: The rectifying unit comprises a diode; The anode of the diode is connected to the voltage-dividing resistor, and the cathode of the diode is connected to the filtering unit.

8. The gear position detection circuit according to claim 6, characterized in that: The filtering unit includes a fourth resistor, a first capacitor and a second capacitor; One end of the first capacitor is connected to the rectifier unit and one end of the fourth resistor respectively, and the other end of the first capacitor is grounded; the other end of the fourth resistor is connected to one end of the second capacitor and the detection end respectively, and the other end of the second capacitor is grounded.

9. The gear position detection circuit according to claim 8, characterized in that: The filtering unit further includes a fifth resistor; The fifth resistor is connected to the other end of the fourth resistor, and the other end of the fifth resistor is grounded.

10. A hair dryer, characterized in that: It comprises the gear position detection circuit as described in any one of claims 1 to 9.

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