CN109716915B - Capacitive sensor and lawn mower - Google Patents
Capacitive sensor and lawn mower Download PDFInfo
- Publication number
- CN109716915B CN109716915B CN201810827511.9A CN201810827511A CN109716915B CN 109716915 B CN109716915 B CN 109716915B CN 201810827511 A CN201810827511 A CN 201810827511A CN 109716915 B CN109716915 B CN 109716915B
- Authority
- CN
- China
- Prior art keywords
- sensor
- layer
- signal
- current source
- signal layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The invention relates to a capacitive sensor and a mower, wherein the capacitive sensor comprises a sensor probe, a connecting wire and a signal processing circuit; the signal processing circuit is connected with the sensor probe through a connecting wire; the connecting wire comprises a sensor signal layer, a first insulating layer, a shielding signal layer and a second insulating layer, wherein the first insulating layer, the shielding signal layer and the second insulating layer are sequentially coated on the outer surface of the sensor signal layer; the signal processing circuit is provided with a sensor signal port and a shielding signal port; the sensor signal port is used for detecting a sensor signal transmitted by the sensor signal layer; the shielding signal port is connected with the shielding signal layer; the signal processing circuit is used for controlling the level of the signals in the sensor signal layer and the shielding signal layer to be consistent. The capacitance sensor can improve the detection accuracy.
Description
Technical Field
The invention relates to the technical field of electrician tools, in particular to a capacitive sensor and a mower.
Background
In order to reduce idle running of the mower and improve working efficiency, most intelligent mowers are provided with a capacitance sensor. The capacitive sensor judges whether the lawn is a grass cluster to be mowed or not by detecting the height of the lawn, and then controls the working condition of the mowing motor. However, in the process of transmitting the signals detected by the traditional capacitive sensor to a signal processing circuit, the wires are easily interfered by other signal wires and conductors, so that the accuracy of the capacitive sensor for detecting the grass height is reduced.
Disclosure of Invention
Accordingly, there is a need for a capacitive sensor and a lawn mower that can improve detection accuracy.
A capacitance sensor is used for detecting an object to be detected and comprises a sensor probe, a connecting wire and a signal processing circuit; the signal processing circuit is connected with the sensor probe through the connecting wire;
the connecting line comprises a sensor signal layer positioned on the innermost layer, and a first insulating layer, a shielding signal layer and a second insulating layer which are sequentially coated on the outer surface of the sensor signal layer; the signal processing circuit is provided with a sensor signal port and a shielding signal port; the sensor signal port is connected with the sensor signal layer; the shielding signal port is connected with the shielding signal layer; the signal processing circuit is used for controlling the signal levels in the sensor signal layer and the shielding signal layer to be consistent.
The connecting line of the capacitance sensor is also provided with a shielding signal layer between the sensor signal layer of the innermost layer and the second insulating layer. The signal processing circuit controls the signal levels in the sensor signal layer and the shielding signal layer to be consistent, so that when interference occurs outside the connecting wire, because the signal levels in the shielding signal layer and the sensor signal layer are consistent, the sensor signal layer does not leak charges to the outside or input charges from the outside, the interference input on the connecting wire is reduced to the maximum extent, and the detection accuracy is improved.
In one embodiment, the signal processing circuit is configured to perform charge and discharge control on the sensor signal layer and the shielding signal layer respectively so that the levels of signals in the sensor signal layer and the shielding signal layer are consistent.
In one embodiment, the signal processing circuit includes a control unit, a first charging unit, a second charging unit, a first discharging unit, and a second discharging unit; the first charging unit and the first discharging unit are respectively connected with the sensor signal layer; the second charging unit and the second discharging unit are respectively connected with the shielding signal layer; the control unit is connected with the first charging unit and the first discharging unit through the sensor signal port; the control unit is also connected with the second charging unit and the second discharging unit through the shielding signal port.
In one embodiment, the control unit is configured to control the first charging unit and the second charging unit to be turned on simultaneously, or control the second charging unit to be turned on within a preset time after the first charging unit operates.
In one embodiment, the first charging unit includes a first current source and a first charging switch; the control unit controls the working state of the first current source by controlling the first charging switch so as to realize charging control of the sensor signal layer;
the second charging unit comprises a second current source and a second charging switch; the control unit controls the working state of the second current source by controlling the second charging switch so as to realize the charging control of the shielding signal layer;
the first current source and the second current source are independent current sources, or the first current source and the second current source are the same current source.
In one embodiment, the first charging unit further comprises a first voltage stabilizing circuit; the second charging unit further comprises a second voltage stabilizing circuit; the first current source is grounded through the first voltage stabilizing circuit; the first voltage stabilizing unit is used for stabilizing the output voltage of the first current source; the second current source is grounded through the second voltage stabilizing circuit; the second regulated current is used for stabilizing the output voltage of the second current source.
In one embodiment, the connecting line further comprises a ground signal layer and a third insulating layer which are sequentially coated on the outer surface of the second insulating layer; the third insulating layer is used for realizing the electrical isolation between the ground signal layer and the outside and is used as a protective layer of the connecting wire.
A mower comprises a shell, a cutting mechanism, a traveling mechanism and a control device, wherein the control device is used for controlling the cutting mechanism and the traveling mechanism and further comprises a capacitance sensor; the capacitance sensor is the capacitance sensor of any one of the previous embodiments;
the control device is used for controlling the cutting mechanism according to the change of the capacitance value of the capacitance sensor.
In one embodiment, the device further comprises a fixing structure; one end of the fixed structure is fixedly connected with the sensor probe; the other end of the fixed structure is fixed on the shell; the fixing structure is further coated outside the connecting wire.
In one embodiment, the connecting wires of the capacitive sensor are arranged in a different wiring level than other tracks on the lawn mower.
Drawings
FIG. 1 is a schematic diagram of a capacitive sensor in one embodiment;
FIGS. 2 and 3 are cross-sectional views of the bond wires of the capacitive sensor at different cross-sectional lines in one embodiment;
FIG. 4 is a schematic diagram of signals transmitted by a sensor signal layer and a shield signal layer in one embodiment;
FIG. 5 is a functional block diagram of a signal processing circuit in one embodiment;
FIG. 6 is a circuit schematic of a capacitive sensor in one embodiment;
FIG. 7 is a circuit schematic of a capacitive sensor in another embodiment;
FIG. 8 is a schematic view of an embodiment of a lawn mower;
FIG. 9 is a schematic view of a fastening structure in an embodiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The capacitance sensor in one embodiment is configured to convert a physical quantity or a mechanical quantity to be measured into a capacitance variation, so that the physical quantity or the mechanical quantity to be measured is detected by detecting the capacitance variation. For example, in one embodiment, a capacitive sensor is used to detect the height of the test object. The test object may be vegetation. In this embodiment, the test object is taken as a grass field as an example for explanation. The capacitance sensor is used for detecting the grass height. Referring to fig. 1, a capacitive sensor 100 in one embodiment includes a sensor probe 110, a connecting wire 120, and a signal processing circuit 130. The signal processing circuit 130 is connected to the sensor probe 110 via a connection line 120.
The sensor probe 110 is a metal probe. The sensor probe 110 serves as one electrode of the capacitive sensor 100 for sensing grass, and the circuit ground or earth serves as the other electrode of the capacitive sensor 100. In this way, the sensor probe 110 and circuit ground or earth ground can form the capacitive structure of the capacitive sensor 100, which is simple and cost effective. In the present embodiment, the earth is used as the other electrode of the capacitance sensor 100, so that the capacitance structure of the capacitance sensor 100 can be formed by the sensor probe 110 and the earth by connecting the sensor probe 110 to the earth.
The connection line 120 includes a sensor signal layer 210, a first insulating layer 220, a shield signal layer 230, a second insulating layer 240, a ground signal layer 250, and a third insulating layer 260, which are positioned at the innermost layer, as shown in fig. 2 and 3. The first insulating layer 220, the shielding signal layer 230, the second insulating layer 240, the ground signal layer 250, and the third insulating layer 260 are sequentially coated on the outer surface of the sensor signal layer 210, that is, the sensor signal layer 210, the first insulating layer 220, the shielding signal layer 230, the second insulating layer 240, the ground signal layer 250, and the third insulating layer 260 are sequentially arranged from inside to outside along the radial direction of the connection line 120. The sensor signal layer 210 is used to transmit a signal required in the sensing process, which may be a current signal. The mask signal layer 220 is used for transmitting a mask signal. The first insulating layer 220 is used for electrically isolating the sensor signal layer 210 from the shielding signal layer 230, and the second insulating layer 240 is used for electrically isolating the shielding signal layer 230 from the ground signal layer 250. The third insulating layer 260 can electrically isolate the ground signal layer 250 from the outside, and at the same time, serves as a protective layer for the connection line 120 to protect the entire connection line 120. In other embodiments, the connection line 120 may only include the sensor signal layer 210, the first insulating layer 220, the shielding signal layer 230, and the second insulating layer 240, and the ground signal layer 250 and the third insulating layer 260 are not provided.
The signal processing circuit 130 is provided with a sensor signal port 132 and a mask signal port 134. The sensor signal port 132 is connected to the sensor signal layer 210 of the connection line 120, and the shielding signal port 134 is connected to the shielding signal layer 230 of the connection line 120. The signal processing circuit 130 is used to control the level of the signal in the sensor signal layer 210 to be consistent with that in the shielding signal layer 230, i.e. to make the signal in the shielding signal layer 230 and the sensor signal layer 210 have the same level flow through, as shown in fig. 4. In one embodiment, the phase and electrical average of the signals in sensor signal layer 210 and shield signal layer 230 are the same. In another embodiment, the signal in sensor signal layer 210 and shield signal layer 230 are the same in phase, amplitude, and frequency. The signal processing circuit 130 is constituted by a chip.
In one embodiment, the signal processing circuit 130 is configured to perform charge and discharge control on the sensor signal layer 210 and the shielding signal layer 230 so that the levels of the signals in the sensor signal layer 210 and the shielding signal layer 230 are consistent. The capacitive sensor of the present embodiment will be further described with reference to the working principle of the capacitive sensor. The signal processing circuit 130 in the capacitive sensor is used for charging and discharging the sensor signal layer 210, that is, charging and discharging the probe 110, so as to determine the capacitance according to the charging and discharging current. When the signal processing circuit 130 controls the current in the sensor signal layer 210 to charge the probe 110 (that is, the electrical signal of the sensor signal layer 210 is a charging signal), an electrical signal which is the same as the charging process is generated as a shielding signal to charge the shielding signal layer 230; when the signal processing circuit 130 discharges the probe 110, the same discharge signal as the sensor signal layer 210 is generated as a shield signal to discharge the shield signal layer 230. The connecting line 120 of the capacitive sensor 100 is further provided with a shielding signal layer 230 between the innermost sensor signal layer 210 and the ground signal layer 250 for transmitting a shielding signal. The signal processing circuit 130 controls the levels of the signals in the sensor signal layer 210 and the shield signal layer 230 to be identical. Therefore, when interference occurs outside the connection line, because the signal levels in the sensor signal layer 210 and the shielding signal layer 230 are consistent, the sensor signal layer 210 does not leak charges to the outside or input charges from the outside, thereby realizing that the parasitic capacitance between the sensor signal layer and the external is blocked by the shielding signal, reducing the interference input on the connection line to the maximum extent, and improving the accuracy of detection.
In one embodiment, the signal processing circuit 130 includes a buffer 136, as shown in FIG. 1. The buffer 136 is used to supply the current required for the shielding signal to the shielding signal layer 230.
In one embodiment, the sensor probe 110 may be fabricated from a metal plate, thereby allowing the sensor probe 110 to have a larger detection range. The sensor signal layer 210, the shield signal layer 230, and the ground signal layer 250 are all fabricated using benign conductors, such as copper, aluminum, and the like. In one embodiment, the sensor signal layer 210 is a solid cylindrical structure, and the other layers are hollow cylindrical structures. In other embodiments, the sensor signal layer 210 is a solid cylinder structure, and the shielding signal layer 230 and the ground signal layer 250 are both mesh structures made of benign conductive material, thereby saving cost and reducing the volume of the connecting wires 120. The first insulating layer 220, the second insulating layer 240 and the third insulating layer 260 may be made of the same or different insulating materials, such as insulating rubber or plastic.
In one embodiment, the signal processing circuit 130 includes a control unit 310, a first charging unit 320, a second charging unit 330, a first discharging unit 340, and a second discharging unit 350, as shown in fig. 5. The first charging unit 320 and the first discharging unit 340 are respectively connected to the sensor signal layer 210. The second charging unit 330 and the second discharging unit 350 are respectively connected to the shielding signal layer 230. The control unit 310 is connected to the first charging unit 320 and the first discharging unit 340 through sensor signal ports J1 and J2, respectively. The control unit 310 is also connected to the second charging unit 330 and the second discharging unit 350 through the shield signal ports J3 and J4, respectively. The control unit 310 is configured to control the first charging unit 320, the second charging unit 330, the first discharging unit 340, and the second discharging unit 350, so as to realize charging and discharging control of the sensor signal layer 210 and the shielding signal layer 230.
In an embodiment, the control unit 310 may implement synchronous charge and discharge control of the sensor signal layer 210 and the shielding signal layer 230 through control of the first charging unit 320, the second charging unit 330, the first discharging unit 340, and the second discharging unit 350. For example, after the capacitive sensor is turned on, the first charging unit 320 and the second charging unit 330 are controlled to be simultaneously turned on and output the same current to simultaneously charge the sensor signal layer 210 and the shielding signal layer 230 so that the levels of the sensor signal layer 210 and the shielding signal layer 230 are the same. In other embodiments, the currents output by the first charging unit 320 and the second charging unit 330 may not be the same as long as a sufficiently strong current is provided to raise the parasitic capacitance to the same level as the sensor signal. At this time, the external interference can be shielded by the shielding signal layer 230, so as to prevent the sensor signal layer 210 from interfering with the external interference to generate a parasitic capacitance to affect the measurement result. In the discharging process, the first and second discharge units 340 and 350 are controlled by the control unit 310 to discharge the sensor signal layer 210 and the shielding signal layer 230, respectively. In the present embodiment, both may be considered to be simultaneously turned on as long as the deviation of the turn-on times of both is within the allowable range. By controlling the charge and discharge of the two layers at the same time, the capacitive sensor can be ensured to have better anti-interference performance. The control unit 310 may be an MCU (microprocessor).
In another embodiment, the control unit 310 controls the second charging unit 330 to start operating within a preset time after the first charging unit 320 operates, that is, controls the second charging unit 330 to lag behind the first charging unit 320 by the preset time. A too long predetermined time of hysteresis may cause the capacitive sensor to have no interference immunity in the early stage of the initial detection, thereby reducing the interference immunity of the capacitive sensor. In one embodiment, the predetermined time cannot exceed one-fourth of the charge-discharge cycle.
FIG. 6 is a circuit schematic of a capacitive sensor in one embodiment. The first charging unit 320 in the capacitive sensor includes a first charging switch K1 and a first current source S1. The second charging circuit 330 includes a second charging switch K3 and a second current source S2. The control unit 310 is connected to the first charge switch K1 through a sensor signal port J1. The output of the first current source S1 is connected to the sensor signal layer 210 through a first charge switch K1. The control unit 310 is also connected to the second charge switch K3 through the shield signal port J3. The second current source S2 is connected to the shielding signal layer 230 through the second charge switch K3. The control unit 310 controls whether the first current source S1 charges the sensor signal layer 210 by controlling the first charging switch K1 to be turned on and off. The control unit 310 controls whether the second current source S2 charges the shield signal layer 230 through switching and closing control of the second charge switch K3. In the present embodiment, the first current source S1 and the second current source S2 belong to two current sources independent of each other, and can output the same or different currents satisfying the charging requirement. The same in the present embodiment means substantially the same, that is, the same can be considered as long as the deviation between the two is within the allowable deviation range.
In another embodiment, the first current source S1 and the second current source S2 may be the same current source, as shown in fig. 7. The current source in fig. 7 may correspond to the buffer 136 in fig. 1. By sharing the first current source S1 and the second current source S2 with one current source, the weight of the entire capacitive sensor can be reduced, which is more advantageous for the miniaturization of the capacitive sensor.
In one embodiment, the first discharge unit 340 and the second discharge unit 350 have the same circuit structure, so that the sensor signal layer 210 and the signal shielding layer 230 have the same discharge rate, thereby ensuring that the level on the signal shielding layer 230 and the level on the sensor signal layer 210 are kept as consistent as possible, so as to improve the interference resistance of the capacitive sensor. Referring to fig. 6 and 7, in an embodiment, the first discharge unit 340 includes a first discharge switch K2, and the second discharge unit 350 includes a second discharge switch K4. The sensor signal layer 210 is grounded through the first discharge switch K2, and the shield signal layer 230 is grounded through the second discharge switch K4. The control unit 310 controls the discharge of the sensor signal layer 210 and the shield signal layer 230 by controlling the turn-on and turn-off of the first discharge switch K2 and the second discharge switch K4.
In one embodiment, the first charging unit 320 further includes a first voltage regulating circuit C1, and the second charging unit 330 further includes a second voltage regulating circuit C2. The first voltage regulator C1 is used for stabilizing the output voltage of the first current source S1, and the second voltage regulator C2 is used for stabilizing the output voltage of the second voltage source S2. The first regulation circuit C1 and the second regulation circuit C2 may each include a regulation capacitor. One end of the voltage-stabilizing capacitor is connected to the current source, and the other end is grounded, as shown in fig. 6. When the first current source S1 and the second current source S2 are the same current source, the first stabilizing circuit C1 and the second stabilizing circuit C2 are the same stabilizing circuit, as shown in fig. 7.
The working principle of the capacitive sensor in this embodiment is further explained with reference to fig. 6 as follows: specifically, the first current source S1 charges and discharges the capacitive sensor through the first charge switch K1 and the first discharge switch K2. When the first charging switch K1 is opened and the first discharging switch K2 is closed, the charge on the probe can leak to the ground, and the level is reduced to zero; when the first charging switch K1 is closed and the first discharging switch K2 is opened, the first current source S1 charges the sensor probe 110, and when the capacitance on the sensor probe 110 is larger, the charging time is longer, and the control unit 310 reads the charging time of the first current source S1 to know the capacitance of the sensor probe 110. The second current source S2 controls the level on the shielding signal layer 230 in a similar manner, i.e. when the first charging switch K1 is closed and the first discharging switch K2 is open, the second charging switch K3 in the shielding signal is closed and the second discharging switch K4 is open, so that a signal corresponding to the sensor signal layer 210 is formed in the shielding signal layer 230. Because the shielding signal is consistent with the sensor signal, the sensor signal and the external parasitic capacitance are blocked by the shielding signal, thereby reducing the interference of the outside to the sensor.
The present application further provides a lawn mower. Fig. 8 is a schematic structural diagram of a mower including a housing 510, a cutting mechanism 520, a traveling mechanism 530, a control device (not shown), and a capacitive sensor 100 according to an embodiment. The control device is connected to the cutting mechanism 520 and the traveling mechanism 530, respectively, and is configured to control the cutting mechanism 520 and the traveling mechanism 530. The mower is an automatic mower, and the control device controls the traveling mechanism to drive the automatic mower to travel and controls the cutting mechanism to execute a mowing task.
The capacitive sensor 100 employs the capacitive sensor of any of the embodiments described above. The capacitive sensor 100 may be provided in plural numbers, respectively disposed at the front and rear ends of the lawn mower. The sensing areas of multiple capacitive sensors 100 may be joined together to form a continuous sensing area having a width greater than or equal to the cutting diameter of the cutting mechanism 520. Therefore, the grass in the cutting range can be detected, and the situation that the grass height in a local area is proper but the grass height in a specific area is high is avoided. In this embodiment, three capacitive sensors are provided at each of the front and rear ends of the mower. The sensor probe 110 may be positioned in front of the front drive wheels and behind the rear drive wheels in the travel mechanism 530 to avoid the drive wheels from entering the hazard zone. In one embodiment, the spacing between two adjacent sensor probes 110 should be greater than 1 mm to ensure that no interference occurs between the sensor probes 110.
When the capacitive sensor 100 detects grass, its capacitance changes with the grass height. The control device is used for detecting the capacitance value of the capacitance sensor 100. The control device controls the cutting mechanism 520 to cut grass on the lawn to a target height based on changes in the capacitance value of the capacitive sensor 100.
In one embodiment, the lawn mower further comprises a fixing structure 560. The securing structure 560 is used to secure the capacitive sensor 100 to the housing. Fig. 9 is a schematic structural diagram of a fixing structure 560 in an embodiment. One end of the fixed structure 560 is fixedly connected to the sensor probe 110. The other end of the fixing structure 560 is fixed to the housing 510 by a fixing member 700. The fixing member 700 may be a screw or a bolt. The fixing structure 560 is also coated outside the connecting wire 120, so as to fix the connecting wire 120 and protect the connecting wire 120. In one embodiment, the fixing structure 560 may be made of an elastic insulating material. The elastic insulating material may be an elastic rubber. In one embodiment, the fixing structure 560 may be a hollow cylindrical structure.
In an embodiment, the connection wires 120 of the capacitive sensor 100 are arranged between different wiring levels with other tracks on the lawn mower. For example, the connecting wires 120 and the motor connecting wires 90 are disposed between different wiring layers to avoid interference of the connecting wires 120 with other peripheral electronic circuit signals. In one embodiment, the connecting wires 120 may be routed against the bottom layer of the inner surface of the bottom housing of the lawn mower, and a plastic insulating layer with a certain thickness may be attached thereon, while other wires such as motor wires and other sensor wires are routed on the upper layer of the lawn mower. The distance between the wiring layer where the connection line 120 is located and the adjacent wiring layer should be greater than 1 cm, so that interference of the adjacent wiring layer on the connection line 120 is avoided, and the measurement accuracy is further improved.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (8)
1. A capacitive sensor is characterized by comprising a sensor probe, a connecting wire and a signal processing circuit; the signal processing circuit is connected with the sensor probe through the connecting wire;
the connecting line comprises a sensor signal layer positioned on the innermost layer, and a first insulating layer, a shielding signal layer and a second insulating layer which are sequentially coated on the outer surface of the sensor signal layer; the signal processing circuit is provided with a sensor signal port and a shielding signal port; the sensor signal port is connected with the sensor signal layer; the shielding signal port is connected with the shielding signal layer;
the signal processing circuit is used for respectively controlling charging and discharging of the sensor signal layer and the shielding signal layer so as to enable the levels of signals in the sensor signal layer and the shielding signal layer to be consistent;
the signal processing circuit comprises a control unit, a first charging unit, a second charging unit, a first discharging unit and a second discharging unit; the first charging unit and the first discharging unit are respectively connected with the sensor signal layer; the second charging unit and the second discharging unit are respectively connected with the shielding signal layer; the control unit is connected with the first charging unit and the first discharging unit through the sensor signal port; the control unit is also connected with the second charging unit and the second discharging unit through the shielding signal port.
2. The capacitive sensor according to claim 1, wherein the control unit is configured to control the first charging unit and the second charging unit to be turned on simultaneously, or control the second charging unit to be turned on within a preset time after the first charging unit is turned on.
3. The capacitive sensor of claim 1 wherein the first charging unit comprises a first current source and a first charging switch; the control unit controls the working state of the first current source by controlling the first charging switch so as to realize charging control of the sensor signal layer;
the second charging unit comprises a second current source and a second charging switch; the control unit controls the working state of the second current source by controlling the second charging switch so as to realize the charging control of the shielding signal layer;
the first current source and the second current source are independent current sources, or the first current source and the second current source are the same current source.
4. The capacitive sensor of claim 3 wherein the first charging unit further comprises a first voltage stabilizing circuit; the second charging unit further comprises a second voltage stabilizing circuit; the first current source is grounded through the first voltage stabilizing circuit; the first voltage stabilizing circuit is used for stabilizing the output voltage of the first current source; the second current source is grounded through the second voltage stabilizing circuit; the second voltage stabilizing circuit is used for stabilizing the output voltage of the second current source.
5. The capacitive sensor of claim 1 wherein the connecting wire further comprises a ground signal layer and a third insulating layer sequentially coated on an outer surface of the second insulating layer; the third insulating layer is used for realizing the electrical isolation between the ground signal layer and the outside and is used as a protective layer of the connecting wire.
6. A mower comprises a shell, a cutting mechanism, a traveling mechanism and a control device, wherein the control device is used for controlling the cutting mechanism and the traveling mechanism and is characterized by further comprising a capacitance sensor; the capacitance sensor is the capacitance sensor as claimed in any one of claims 1 to 5;
the control device is used for controlling the cutting mechanism according to the change of the capacitance value of the capacitance sensor.
7. The mower of claim 6 further comprising a fixed structure; one end of the fixed structure is fixedly connected with the sensor probe; the other end of the fixed structure is fixed on the shell; the fixing structure is further coated outside the connecting wire.
8. The lawnmower of claim 7, wherein the connecting wires of the capacitive sensor are arranged in a different wiring layer than other tracks on the lawnmower.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711036995 | 2017-10-30 | ||
| CN2017110369957 | 2017-10-30 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109716915A CN109716915A (en) | 2019-05-07 |
| CN109716915B true CN109716915B (en) | 2021-01-05 |
Family
ID=66294595
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810827511.9A Active CN109716915B (en) | 2017-10-30 | 2018-07-25 | Capacitive sensor and lawn mower |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109716915B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204575095U (en) * | 2015-05-11 | 2015-08-19 | 天津吉诺科技有限公司 | A kind of capacitive transducer with shield assembly |
| CN205825980U (en) * | 2016-06-15 | 2016-12-21 | 苏州宝时得电动工具有限公司 | Capacitance sensor and hay mover |
| CN107027433A (en) * | 2016-02-03 | 2017-08-11 | 苏州宝时得电动工具有限公司 | Hay mover |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110036065A1 (en) * | 2009-08-11 | 2011-02-17 | Yen Wen Wong | Lawn mower powered by a compression-ignited combustion engine that can use multiple fuel types |
-
2018
- 2018-07-25 CN CN201810827511.9A patent/CN109716915B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204575095U (en) * | 2015-05-11 | 2015-08-19 | 天津吉诺科技有限公司 | A kind of capacitive transducer with shield assembly |
| CN107027433A (en) * | 2016-02-03 | 2017-08-11 | 苏州宝时得电动工具有限公司 | Hay mover |
| CN205825980U (en) * | 2016-06-15 | 2016-12-21 | 苏州宝时得电动工具有限公司 | Capacitance sensor and hay mover |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109716915A (en) | 2019-05-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1281097C (en) | Proximity detector between a metallic mass and an element to which isapplied an electric voltage | |
| US4464622A (en) | Electronic wall stud sensor | |
| US9726775B2 (en) | Capacitive sensing device | |
| EP3412136B1 (en) | Self-moving device and control method therefor | |
| CN107599848A (en) | High voltage detection circuit, detector, battery device and vehicle | |
| CN108490302A (en) | ground fault detector | |
| KR20110097851A (en) | Capacitive sensor system | |
| US11327100B2 (en) | Electrostatic sensor and door handle | |
| WO2014023402A1 (en) | Medium or high voltage arrangement with cable connection terminal | |
| CN205825980U (en) | Capacitance sensor and hay mover | |
| KR20090087937A (en) | Arrangement for the detection of body parts by absorbing an electric near field | |
| CN106443329A (en) | System and method for detecting fault of DC grounding electrode line | |
| US7999562B2 (en) | Apparatus and method of capacitively sensing operator presence for a stump cutter | |
| EP4060847A1 (en) | Anti-electric-shock monitoring and protection method and apparatus for low-voltage user end | |
| CN109716915B (en) | Capacitive sensor and lawn mower | |
| CN106888673A (en) | Hay mover | |
| US6255812B1 (en) | Shearbar/cutterhead monitoring system with spatially separated magnet | |
| CA2741310C (en) | Sensor device for detecting an object in a detection area | |
| KR100396043B1 (en) | Method and apparatus for detecting and identifying electrical cables | |
| US11163013B2 (en) | Electrical device partial discharge monitoring | |
| SE522879C2 (en) | Device for an electric fence | |
| CN103036220B (en) | Electro spark detector (ESD) circuit protection structure | |
| CN201726102U (en) | Intelligent current leakage protection circuit | |
| JP2012506190A (en) | Object detection device for an automatic vehicle | |
| CN216672595U (en) | Half-bridge IGBT (insulated Gate Bipolar transistor) protection circuit of induction cooker and induction cooker |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |