Electromagnetic induction-based transducer and control circuit

Abstract

A transducer and a control circuit based on electromagnetic induction are provided with a mounting seat, a magnet mounting column is fixedly connected to the middle of the upper end face of the mounting seat, and a magnet is connected to the other end of the magnet mounting column; the magnet mounting column is sleeved with a vibration response piece, and the two ends of the vibration response piece are connected with the mounting base and the magnet respectively; an induction coil is arranged at one end of the vibration response piece and is close to the magnet. The overall structure is simple, the combination of the permanent magnet, the spring detection piece and the induction coil is utilized, when vibration is detected, mechanical energy of movement of the spring detection piece is converted into electric signals through the induction coil, then the induction coil is powered on, and the electric energy can be converted into mechanical movement energy through the spring detection piece. The requirements for vibration information collection and force feedback in special application scenes are met, and the device can be widely applied to application scenes with keys, simulation tentacles, sensors and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and particularly to a transducer and a control circuit based on electromagnetic induction. Background Art

[0002] In the prior art, sensors capable of detecting vibrations are mainly acceleration sensors based on microelectromechanical systems and vibration displacement sensors based on optics. However, these current sensors can only achieve unidirectional transmission from mechanical motion to electrical signals and cannot achieve bidirectional transmission between mechanical motion and electrical signals. If the prior art sensors want to achieve the transmission process from electrical signals to mechanical motion, other electromechanical devices such as motors and relays need to be used. Summary of the Invention

[0003] I. Technical Problems to be Solved

[0004] In view of the deficiencies of the prior art, the present invention provides a transducer and a control circuit based on electromagnetic induction that can achieve bidirectional transmission between mechanical motion and electrical signals, are small in size and light in weight, and are applicable to various application scenarios of vibration measurement and vibration feedback.

[0005] II. Specific Technical Solutions <UNK>

[0006] A transducer based on electromagnetic induction is provided with a mounting base (1). In the middle of the upper end face of the mounting base (1), a magnet mounting column (2) is fixedly connected. At the other end of the magnet mounting column (2), a magnet (3) is connected. A vibration response member (4) is sleeved on the magnet mounting column (2). Both ends of the vibration response member (4) are respectively connected to the mounting base (1) and the magnet (3). An induction coil (5) is provided at one end of the vibration response member (4), and the induction coil (5) is close to the magnet (3).

[0007] Implementation Principle, Working Principle: During the detection of mechanical motion, the vibration response member (4) is vibrated, driving the induction coil (5) to move along the axial direction of the magnet mounting column (2). Under the action of the magnetic field of the magnet (3), an induced current is generated in the moving induction coil (5), realizing the conversion of mechanical vibration into an electrical signal.

[0008] In the transmission mode, a current is applied to the induction coil (5) through the control circuit. A magnetic field will be generated in the induction coil (5) and interact with the magnetic field of the magnet (3). As a result, the magnet (3) drives the mounting base (1) to move relative to the induction coil (5) through the magnet mounting post (2), and at the same time, energy is stored in the vibration response member (4). When the current is appropriate, the repulsive force between the magnetic fields generated by the magnet (3) and the induction coil (5) and the elastic force of the vibration response member (4) will reach a balance. At this time, the induction coil (5) can remain relatively stationary at any appropriate position within the stroke. By changing the current in the induction coil (5), the magnet (3) and the mounting base (1) can generate the required motion characteristics. This is a reverse process of the sensor mode and cannot be achieved by existing sensor devices.

[0009] Preferably, the induction coil (5) is sleeved on the outer wall of the vibration response member (4), fixedly connected to the outer wall of the vibration response member (4), and installed relative to the inner wall. The installation is simple and the maintenance and replacement are convenient.

[0010] Preferably, the vibration response member (4) is a spring coil, with linear motion, which improves the precision of the detected data.

[0011] Preferably, the spring coil is made of a metal material. The metal material has a large elasticity, excellent linear motion, and low processing cost.

[0012] Preferably, the mounting base (1) has a circular sheet-like structure. The magnet mounting post (2) is integrally formed at the center position of the upper surface of the mounting base (1), and the magnet mounting post (2) and the mounting base (1) are made of a non-magnetic material. The use of an integrally formed structure reduces the installation process and makes the installation more convenient.

[0013] Preferably, the magnet (3) has a cylindrical structure and is made of a permanent magnet material. It has high magnetic stability, does not require energy consumption, and is convenient for the implementation of the present invention.

[0014] Preferably, the vibration response member (4) is provided with an elastic connection strip, which is distributed along the outer wall of the magnet mounting post (2). The two ends of the elastic connection strip are respectively connected to the inner end surfaces of the mounting base (1) and the magnet (3). For example, an elastic connection strip made of rubber material is used, which is convenient for replacement. By adjusting the length of the rubber strip, the force can be changed, and the detection range of the present invention can be expanded.

[0015] A control circuit based on an electromagnetic induction transducer is provided with a drive circuit. One end of the power input terminal of the drive circuit is connected to the power supply VDD, and the other end is grounded. The output terminal of the drive circuit is connected to the input terminal of the induction coil (5). The drive circuit is provided with an MOS transistor Q1. The gate of the MOS transistor Q1 is connected to the control signal PWM1, the drain is connected to the power supply VDD, and the source is connected to the drain of the MOS transistor Q2 on one path and connected to the first input terminal of the induction coil (5) through the inductor L2 on the other path. A capacitor C1 is also connected between the source of the MOS transistor Q1 and the inductor L2, and the other end of the capacitor C1 is grounded. The gate of the MOS transistor Q2 is connected to the control signal PWM2, and the source is grounded. An MOS transistor Q3 is also provided. The drain of the MOS transistor Q3 is connected to the power supply VDD, the gate is connected to the control signal PWM3, and the source is connected to the source of the MOS transistor Q4 on one path and connected to the second input terminal of the induction coil (5) through the inductor L3 on the other path. A capacitor C2 is also connected between the source of the MOS transistor Q3 and the inductor L3, and the other end of the capacitor C2 is grounded. The gate of the MOS transistor Q4 is connected to the control signal PWM4, and the source is grounded.

[0016] Preferably, a detection circuit is provided. The detection circuit is provided with an amplifier U1. One path of the positive terminal of the amplifier U1 is connected to the first input terminal of the induction coil (5) through a resistor R1, and the other path is connected to the reference power supply VREF through a resistor R3. One path of the negative terminal of the amplifier U1 is connected to the second input terminal of the induction coil (5) through a resistor R2, and the other path is connected to the output terminal of the amplifier U1 through a resistor R4. The output terminal of the amplifier U1 is the detection signal output terminal.

[0017] The beneficial effects of the present invention are as follows: The overall structure is simple. By using the combination of a permanent magnet, a spring detection member, and an induction coil, when detecting vibration, the mechanical energy of the movement of the spring detection member is converted into an electrical signal through the induction coil. When the induction coil is connected to electrical energy, the electrical energy can be converted into mechanical kinetic energy through the spring detection member, realizing the requirements of vibration information acquisition and force feedback in special application scenarios, and can be widely applied in application scenarios such as with buttons, analog tentacles, sensors, etc.

[0018] The setting of the drive circuit provides a stable current for the induction coil of the device, enabling the coil and the permanent magnet to generate a force for relative movement, pushing the permanent magnet to move in the approaching or departing direction, compressing or stretching the spring coil, thereby changing the pressure applied to the contact surface of the structural member.

[0019] The setting of the detection circuit. The main function of this circuit is to detect the induced voltage generated on the induction coil when the permanent magnet moves relative to the induction coil, realizing the conversion of mechanical energy into electrical signals. Description of the Drawings

[0020] Figure 1It is a structural schematic diagram of the present invention.

[0021] Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention.

[0022] Figure 3 This is a structural diagram of embodiment 2 of the present invention.

[0023] Figure 4 It is a structural diagram of the control circuit in the present invention. DETAILED DESCRIPTION

[0024] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings to make the advantages and features of the present invention easier for those skilled in the art to understand, thereby making a clearer and more precise definition of the scope of protection of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] Example 1:

[0026] like Figure 1 and Figure 2 As shown: A transducer based on electromagnetic induction is provided with a sheet-shaped circular mounting base 1, and a magnet mounting column 2 is fixedly connected to the middle of the upper end surface of the mounting base 1. The mounting base 1 and the magnet mounting column 2 are integrally formed by plastic injection molding, and a cylindrical permanent magnet 3 is connected to the other end of the magnet mounting column 2; a vibration response member 4 is sleeved on the magnet mounting column 2, and the vibration response member 4 is a metal spring coil structure, and the two ends of the vibration response member 4 are respectively abutted against the mounting base 1 and the magnet 3, or fixedly connected; an induction coil 5 is provided on the outer surface of one end of the vibration response member 4, and the induction coil 5 is close to the magnet 3.

[0027] During the detection of mechanical movement, the metal spring coil is vibrated, driving the induction coil 5 to move along the axial direction of the magnet mounting column 2. Under the action of the magnetic field of the magnet 3, the moving induction coil 5 generates an induced current, thereby converting the mechanical vibration into an electrical signal.

[0028] In transmission mode, an external circuit applies current to the induction coil 5, generating a magnetic field in the induction coil 5 that interacts with the magnetic field of the magnet 3. This in turn causes the magnet 3, via the magnet mounting post 2, to drive the mounting base 1 relative to the induction coil 5, while simultaneously storing energy in the metal spring coil. When the current reaches a set value, the repulsive force between the magnetic field generated by the magnet 3 and the induction coil 5 and the elastic force of the metal spring coil reach a balance. At this point, the induction coil 5 can remain relatively stationary at any suitable position within its travel range. By varying the current in the induction coil 5, the magnet 3 and mounting base 1 can produce the desired motion characteristics. This is the reverse process of sensor mode, something that traditional sensor devices cannot achieve.

[0029] As shown in Figure 4 Figure Figure 4 : A control circuit based on an electromagnetic induction transducer is provided with a drive circuit. One end of the power input terminal of the drive circuit is connected to the power supply VDD, and the other end is grounded. The output terminal of the drive circuit is connected to the input terminal of the induction coil 5. The drive circuit is provided with a MOS transistor Q1. The gate of the MOS transistor Q1 is connected to the control signal PWM1, the drain is connected to the power supply VDD, and the source is connected to the drain of the MOS transistor Q2 on one path and to the first input terminal of the induction coil 5 through the inductor L2 on the other path. A capacitor C1 is also connected between the source of the MOS transistor Q1 and the inductor L2, and the other end of the capacitor C1 is grounded. The gate of the MOS transistor Q2 is connected to the control signal PWM2, and the source is grounded. A MOS transistor Q3 is also provided. The drain of the MOS transistor Q3 is connected to the power supply VDD, the gate is connected to the control signal PWM3, the source is connected to the source of the MOS transistor Q4 on one path and to the second input terminal of the induction coil 5 through the inductor L3 on the other path. A capacitor C2 is also connected between the source of the MOS transistor Q3 and the inductor L3, and the other end of the capacitor C2 is grounded. The gate of the MOS transistor Q4 is connected to the control signal PWM4, and the source is grounded.

[0030] During the positive current: The working principle of the drive circuit is to input a PWM control signal with a duty cycle of 0 - 100% to the MOS transistor Q1 to make the MOS transistor Q1 in a chopping working state; input a low-level control signal to the MOS transistor Q2 to make the MOS transistor Q2 in an off working state; input a low-level control signal to the MOS transistor Q3 to make the MOS transistor Q3 in an off working state; input a high-level control signal to the MOS transistor Q4 to make the MOS transistor Q4 in a continuously conducting working state. At this time, the current in the drive circuit flows from the power supply VDD through the chopping of the MOS transistor Q1, is filtered by the capacitor C1 and the inductor L2, passes through the induction coil 5, is filtered by the capacitor C2 and the inductor L3 filter circuit, and finally flows to the GND through the MOS transistor Q4.

[0031] Among them, the current passing through the induction coil 5 is determined by the internal resistance of the power supply and the series equivalent resistance of the inductors L2, L1, L3 and the switching duty cycle.

[0032]

[0033] Where R s is the internal resistance of the power supply, ESR L1 is the induction coil 5, ESR L2 is the series equivalent resistance of the inductor L2, ESR L3 is the series equivalent resistance of the inductor L3, and D is the positive duty cycle of the PWM control signal connected to the MOS transistor Q1.

[0034] During reverse current: Apply a PWM control signal with a duty cycle of 0 - 100% to MOS transistor Q3 to put MOS transistor Q3 in a chopping operating state; apply a low-level control signal to MOS transistor Q4 to put MOS transistor Q4 in an off operating state; apply a low-level control signal to MOS transistor Q1 to put MOS transistor Q1 in an off operating state; apply a high-level control signal to MOS transistor Q2 to put MOS transistor Q2 in a continuously conducting operating state. At this time, the current in the drive circuit flows from power supply VDD through the chopping of MOS transistor Q3, is filtered by capacitor C2 and inductor L3, passes through induction coil 5, is filtered by the filter circuit of capacitor C1 and inductor L2, and finally flows to GND through MOS transistor Q2.

[0035] Among them, the current passing through induction coil 5 is determined by the internal resistance of the power supply and the series equivalent resistance of inductors L2, L1, L3 and the switch duty cycle.

[0036]

[0037] Among them, R s is the internal resistance of the power supply, and ESR L1 is the series equivalent resistance of induction coil 5, and ESR L2 is the series equivalent resistance of inductor L2, and ESR L3 is the series equivalent resistance of inductor L3, and D is the positive duty cycle of the PWM control signal connected to MOS transistor Q3.

[0038] A detection circuit is provided. The detection circuit is provided with an amplifier U1. One path of the positive terminal of the amplifier U1 is connected to the first input terminal of induction coil 5 through a resistor R1, and the other path is connected to the reference power supply VREF through a resistor R3; one path of the negative terminal of the amplifier U1 is connected to the second input terminal of induction coil 5 through a resistor R2, and the other path is connected to the output terminal of the amplifier U1 through a resistor R4. The output terminal of the amplifier U1 is the detection signal output terminal.

[0039] The detection circuit consists of a biased proportional amplifier U1. It is composed of R1, R2, R3, R4 and U1. For the convenience of calculation, the values of R1 and R2 are the same, and the values of R3 and R4 are the same. The amplification factor of the detection circuit is equal to

[0040] Output voltage

[0041] Among them, V L1 is the voltage difference across induction coil 5, and V out is the output voltage of the ADC port.

[0042] Embodiment 2:

[0043] In the case where other structures are the same as those in Embodiment 1, as an optimization:

[0044] As Figure 3 shown: The vibration response member 4 is provided with a rubber elastic connecting strip, which is distributed along the outer wall of the magnet mounting column 2, and both ends of the elastic connecting strip are respectively connected to the mounting seat 1 and the inner end surface of the magnet 3. The induction coil 5 is sleeved on the outer wall of the cylinder formed by the rubber elastic connecting strip. Using the elastic connecting strip to replace the metal spring coil in the first embodiment, the movement of the induction coil 5 is realized, and the replacement of the elastic connecting strip is more convenient. By adjusting the length of the elastic connecting strip, the overall elasticity can be quickly adjusted to adapt to different application scenarios.

[0045] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. An electromagnetic induction-based transducer, characterized in that: There is a mounting base (1), and a magnet mounting post (2) is fixedly connected to the middle of the upper end surface of the mounting base (1). A magnet (3) is connected to the other end of the magnet mounting post (2); A vibration response member (4) is sleeved on the magnet mounting post (2), and both ends of the vibration response member (4) are respectively connected to the mounting base (1) and the magnet (3); An induction coil (5) is arranged at one end of the vibration response member (4), and the induction coil (5) is close to the magnet (3).

2. The transducer based on electromagnetic induction according to claim 1, characterized in that: The induction coil (5) is sleeved on the outer wall of the vibration response member (4).

3. The transducer based on electromagnetic induction according to claim 1, wherein: The vibration response member (4) is a spring coil.

4. The transducer based on electromagnetic induction according to claim 3, wherein: The spring coil is made of a metal material.

5. The transducer based on electromagnetic induction according to claim 1, wherein: The mounting base (1) is a circular sheet-like structure, and the magnet mounting post (2) is integrally formed and connected to the center position of the upper surface of the mounting base (1), and the magnet mounting post (2) and the mounting base (1) are made of non-magnetic materials.

6. The electromagnetic induction-based transducer according to claim 1, wherein: The magnet (3) is a cylindrical structure, and the magnet (3) is made of a permanent magnet material.

7. The transducer based on electromagnetic induction according to claim 1, characterized in that: The vibration response member (4) is provided with elastic connection strips, which are distributed along the outer wall of the magnet mounting post (2), and both ends of the elastic connection strips are respectively connected to the inner end surfaces of the mounting base (1) and the magnet (3).

8. The control circuit of the transducer based on electromagnetic induction according to claim 1, characterized in that: A drive circuit is provided. One end of the power input terminal of the drive circuit is connected to the power supply VDD, and the other end is grounded. The output terminal of the drive circuit is connected to the input terminal of the induction coil (5); Among them, the drive circuit is provided with a MOS transistor Q1. The gate of the MOS transistor Q1 is connected to the control signal PWM1, the drain is connected to the power supply VDD, the source is connected to the drain of the MOS transistor Q2 through one path, and the other path is connected to the first input terminal of the induction coil (5) through an inductor L2. A capacitor C1 is also connected between the source of the MOS transistor Q1 and the inductor L2, and the other end of the capacitor C1 is grounded; The gate of the MOS transistor Q2 is connected to the control signal PWM2, and the source is grounded; A MOS transistor Q3 is also provided. The drain of the MOS transistor Q3 is connected to the power supply VDD, the gate is connected to the control signal PWM3, the source is connected to the source of the MOS transistor Q4 through one path, and the other path is connected to the second input terminal of the induction coil (5) through an inductor L3. A capacitor C2 is also connected between the source of the MOS transistor Q3 and the inductor L3, and the other end of the capacitor C2 is grounded; The gate of the MOS transistor Q4 is connected to the control signal PWM4, and the source is grounded.

9. The control circuit of the electromagnetic induction-based transducer according to claim 8, characterized in that: A detection circuit is provided. The detection circuit is provided with an amplifier U1. One path of the positive terminal of the amplifier U1 is connected to the first input terminal of the induction coil (5) through a resistor R1, and the other path is connected to the reference power supply VREF through a resistor R3; One path of the negative terminal of the amplifier U1 is connected to the second input terminal of the induction coil (5) through a resistor R2, and the other path is connected to the output terminal of the amplifier U1 through a resistor R4. The output terminal of the amplifier U1 is the detection signal output terminal.

Images