Anti-pinch electric door of shielding box

Abstract

The utility model discloses an anti-pinch electrically operated gate of a shielding box, which comprises a gate body, a driving mechanism and a control circuit, the driving mechanism comprises a motor, a lead screw transmission mechanism and a coupler, and the lead screw transmission mechanism is connected with the gate body; the control circuit comprises a processor and a motor driving module electrically connected with the processor; the motor driving module is electrically connected with the motor, and the motor driving module is provided with a current acquisition circuit used for acquiring the current of the motor in the door opening and closing process; an infrared diffuse reflection sensor electrically connected with the processor is further arranged on the lead screw transmission mechanism and used for collecting pulse signals of the lead screw transmission mechanism in the door opening and closing process. The processor is used for judging whether foreign matter is clamped in the door opening and closing process or not according to the magnitude of the current or the pulse signal, and door opening and closing are stopped. According to the utility model, the electric door of the shielding box can be prevented from being pinched in the door opening and closing process.

Description

Technical Field

[0001] The utility model relates to the technical field of signal testing equipment, in particular to an anti-pinch electric door for a shielding box. Background Art

[0002] Shielding boxes are used to shield interference signals when testing the performance of electronic equipment.

[0003] Shielding boxes can be categorized as either manual or power-closed, depending on how the door is opened and closed. Manually closed shielding boxes typically use a 90-degree rotating handle that locks the door together, manually tightening the box body to achieve signal shielding. Power-closed shielding boxes typically use a servo motor or pneumatic cylinder to drive the door toward the box body and tighten it to achieve the desired shielding effect.

[0004] The manual door-closing shielding box requires manual action, is cumbersome to operate, and is not automated enough. Although the electric door-closing shielding box does not require manual closing, the existing electric door-closing shielding box does not have an anti-pinch function and is not safe enough.

[0005] Therefore, the existing technology needs to be improved. Utility Model Content

[0006] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide an anti-pinch electric door for a shielding box, which aims to prevent pinching injuries during the opening and closing process of the electric door of the shielding box.

[0007] To achieve the above-mentioned purpose, the utility model discloses a shielding box anti-pinch electric door, comprising a door body, a drive mechanism, and a control circuit, wherein:

[0008] The driving mechanism includes a motor, a screw transmission mechanism, and a coupling connected between the motor and the screw transmission mechanism, and the screw transmission mechanism is connected to the door body;

[0009] The control circuit includes a processor and a motor drive module electrically connected to the processor;

[0010] The motor drive module is electrically connected to the motor, and the motor drive module is provided with a current acquisition circuit for acquiring the current magnitude of the motor during the door opening and closing process;

[0011] The screw drive mechanism is also provided with an infrared diffuse reflection sensor electrically connected to the processor, for collecting pulse signals of the screw drive mechanism during the door opening and closing process;

[0012] The processor is used to determine whether a foreign object is clamped during the door opening and closing process according to the current size or the pulse signal and stop the door opening and closing.

[0013] In some embodiments, the coupling is a torque limiting coupling.

[0014] In some embodiments, the motor is a brushed DC motor.

[0015] In some embodiments, a door opening detection sensor and a door closing detection sensor are respectively provided at both ends of the screw transmission mechanism in the movement direction;

[0016] The control circuit further includes a timing module electrically connected to the processor;

[0017] The timing module is used to calculate the door opening and closing time after the door opening detection sensor and the door closing detection sensor are triggered, and the processor is used to determine whether there is a foreign object clamped during the door opening and closing process based on the door opening and closing time and stop opening and closing the door.

[0018] In some embodiments, the control circuit further includes an emergency stop switch electrically connected to the processor, and the processor is configured to stop opening and closing the door according to a signal after the emergency stop switch is triggered.

[0019] In some embodiments, the screw transmission mechanism includes a base, a screw, a slider, and a connecting rod;

[0020] Both ends of the screw rod are rotatably mounted on the base body, and one end of the screw rod passes through the base body and is connected to the coupling;

[0021] The screw rod also passes through the slider and is threadedly connected to the slider;

[0022] One end of the connecting rod is connected to the sliding block, and the other end of the connecting rod is connected to the door body.

[0023] In some embodiments, the screw transmission mechanism further includes a guide rod, both ends of which are mounted on the base body, the guide rod passes through the slider, and the slider can slide relative to the guide rod.

[0024] In some embodiments, the motor driving module includes a driving chip connected to the processor and the motor;

[0025] The current acquisition circuit includes a sampling resistor, a first sampling pin provided on the driver chip, and a second sampling pin provided on the processor;

[0026] One end of the sampling resistor is connected to the first sampling pin and the second sampling pin, and the other end is grounded.

[0027] In some embodiments, a current limiting resistor is further connected in series between the sampling resistor and the second sampling pin.

[0028] It should be understood that within the scope of the present invention, the above-mentioned technical features of the present invention and the technical features specifically described below (such as the implementation methods) can be combined with each other to form new or preferred technical solutions. Due to space limitations, they will not be listed here one by one.

[0029] Beneficial effects of the utility model:

[0030] 1. Since an infrared diffuse reflection sensor is provided, the infrared diffuse reflection sensor can collect pulse signals corresponding to changes in the threads of the screw in the screw transmission mechanism during the rotation process. When such pulse signals are irregular, the processor of the control circuit can determine that it is an abnormal state and stop opening and closing the door; at the same time, since a current acquisition circuit is provided in the motor drive module, the current acquisition circuit can collect the current size of the motor during the opening and closing process. When the current size is too large or too small, the processor of the control circuit can determine that it is an abnormal state and stop opening and closing the door. In this way, the shielded box electric door of the present invention has an anti-pinch function.

[0031] 2. The motor of the present invention adopts a brushed DC motor, which is low in cost and simple to control compared to the servo motor in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0033] Figure 1 This is a structural diagram of Example 1 of the shielding box anti-pinch electric door of the present utility model.

[0034] Figure 2 for Figure 1 Schematic diagram of the structure from another perspective.

[0035] Figure 3 for Figure 2 A partial enlarged schematic diagram is shown in the figure.

[0036] Figure 4 This is the circuit diagram of the utility model's shielded box anti-pinch electric door.

[0037] Figure 5 This is a circuit diagram of the processor of the present invention.

[0038] Figure 6 This is a circuit block diagram of the current acquisition circuit of the utility model.

[0039] Figure 7This is a circuit schematic diagram of the current acquisition circuit of the utility model.

[0040] Description of reference numerals:

[0041] 100-electric door, 10-door body, 20-drive mechanism, 21-motor, 22-screw transmission mechanism, 221-base, 222-screw, 223-slider, 224-connecting rod, 225-guide rod, 23-coupling, 30-control circuit, 31-processor, 32-motor drive module, 321-current acquisition circuit, 3211-sampling resistor, 3212-first sampling pin, 3213-second sampling pin, 3124-current limiting resistor, 3215-drive pin, 322-drive chip, 33-timing module, 34-emergency stop switch, 40-infrared diffuse reflection sensor, 50-door opening detection sensor, 60-door closing detection sensor, 70-power module, 80-box. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0043] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0044] In addition, in this utility model, the terms "first," "second," etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include at least one of such features.

[0045] The specific embodiments are as follows, please refer to Figures 1 to 4 The present invention proposes a shielded box anti-pinch electric door 100, which includes a door body 10, a driving mechanism 20, and a control circuit 30. The door body 10 of the present invention is made of metal. The driving mechanism 20 is used to drive the movement of the door body 10 to realize the opening and closing of the door, and the control circuit 30 is used to control the movement of the driving mechanism 20.

[0046] like Figure 2As shown, as a way, the driving mechanism 20 in the present invention includes a motor 21, a screw transmission mechanism 22, and a coupling 23 connected between the motor 21 and the screw transmission mechanism 22, and the screw transmission mechanism 22 is connected to the door body 10. The motor 21 is controlled by the control circuit 30 to start or stop rotation.

[0047] When the motor 21 rotates, it drives the coupling 23 to rotate, and the coupling 23 drives the screw on the screw transmission mechanism 22 to rotate. The rotation of the screw drives the corresponding transmission structure such as the nut, slider, etc. to move linearly, and drives the linear movement of the door body 10 to realize the opening and closing of the door.

[0048] like Figure 3 As shown, the control circuit 30 of the present invention includes a processor 31 and a motor drive module 32 electrically connected to the processor 31. The motor drive module 32 is electrically connected to the motor 21 and is provided with a current acquisition circuit 321 for acquiring the current of the motor 21 during the door opening and closing process. The processor 31 is used to determine whether a foreign object is trapped during the door opening and closing process based on the current and stop the door opening and closing. During normal door opening or closing, the current of the motor 21 generally maintains a stable value because there is no foreign object blocking it. However, when a foreign object such as a hand blocks the door body 10, the motor 21 will be blocked or the transmission will not be smooth. At this time, the rated current of the motor 21 will increase. The processor 31 compares the actual current of the motor 21 with the preset current. When the actual current is much greater than the preset current (i.e., the motor 21 is blocked or the transmission is not smooth), an anti-pinch trigger signal is generated. The trigger signal causes the processor 31 to turn off the motor 21, causing the motor 21 to stop rotating and the door body 10 to stop moving and prevent pinching.

[0049] At the same time, the screw drive mechanism 22 of the electric door 100 of the present invention is also provided with an infrared diffuse reflection sensor 40 electrically connected to the processor 31 for collecting pulse signals from the screw drive mechanism 22 during the door opening and closing process. The processor 31 is used to determine whether a foreign object is trapped during the door opening and closing process based on the pulse signals and stop the door opening and closing process.

[0050] The screw transmission mechanism 22 has a screw, which has threads. The acquisition principle of the infrared diffuse reflection sensor 40 is:

[0051] First, the sensitivity of the infrared diffuse reflection sensor 40 is adjusted so that it outputs a high level when sensing the bottom of the screw thread and a low level when sensing the top of the screw thread. When the electric door 100 of the shielded box is opening or closing, the motor 21 operates at rated power, and the infrared diffuse reflection sensor 40 can output a pulse signal of a fixed frequency to the processor 31 of the control circuit 30. After software filtering, the processor 31 determines that the motor 21 and the screw are operating normally. If an object or a body obstructs the movement of the motor, the infrared diffuse reflection sensor 40 detects that the pulse signal frequency is different from the rated frequency, thus generating an anti-pinch trigger signal. This trigger signal triggers the anti-pinch program in the processor 3, which in turn shuts down the motor 21, thereby achieving the anti-pinch function.

[0052] The electric door 100 of the present invention is further provided with a power module 70 for providing power of corresponding voltage level to the motor 21 and the processor 31 .

[0053] like Figure 5 As shown, the processor 31 of this embodiment is a single chip microcomputer, and the model of the single chip microcomputer is STM32F103RCT6. It can be understood that in other embodiments, the single chip microcomputer can also adopt other models.

[0054] The electric door 100 of the present invention can collect the current of the motor 21 through the current collection circuit 321, and can also collect the pulse signal of the screw rod through the infrared diffuse reflection sensor 40, and then process and judge it through the control circuit 30 to achieve anti-pinch. The two methods work independently. As long as one method triggers anti-pinch, the motor 21 can be turned off to achieve anti-pinch.

[0055] Furthermore, coupling 23 is a torque-limiting coupling. When the torque applied to the torque-limiting coupling exceeds a predetermined value, such as 2.5 Nm, coupling 23 breaks to protect the load. This prevents the clamping of foreign objects during door opening and closing, automatically breaking coupling 23.

[0056] Furthermore, the motor 21 is a brushed DC motor, which has a simple structure and is easy to control, and greatly reduces costs compared to the prior art using a servo motor.

[0057] Preferably, if Figure 2 and Figure 3As shown, a door opening detection sensor 50 and a door closing detection sensor 60 are respectively provided at both ends of the movement direction of the screw transmission mechanism 20. The door opening detection sensor 50 and the door closing detection sensor 60 can be a proximity switch, a travel switch or a light sensor. In this embodiment, the door opening detection sensor 50 is provided on the left side of the screw transmission mechanism 20, and the door closing detection sensor 60 is provided on the right side of the screw transmission mechanism 20. The left side of the screw transmission mechanism 20 is connected to the door body 10, and a slider 223 is provided on the screw sensor mechanism 20. As shown Figure 2 In the process of opening the door, the screw transmission mechanism 20 pushes the door body 10 to the left. When the door is opened, the slider 223 will be detected by the door opening detection sensor 50 to generate a door opening trigger signal and send it to the processor 31; when closing the door, the screw transmission mechanism 20 pulls the door body 10 to the right. When the door is closed, the slider 223 will be detected by the door closing detection sensor 60 to generate a door closing trigger signal and send it to the processor 31.

[0058] like Figure 4 As shown, the control circuit 30 also includes a timing module 33 electrically connected to the processor 31, and the timing module 33 is used to calculate the door opening and closing time after the door opening detection sensor 50 and the door closing detection sensor 60 are triggered. The processor 31 is used to determine whether there is a foreign object clamped during the door opening and closing process based on the door opening and closing time and stop opening and closing the door.

[0059] If the normal door opening and closing time is set to 4.2S, when the time from issuing the door closing command to receiving the door opening trigger signal from the door closing detection sensor 60 is greater than 4.2S, the anti-pinch is triggered, the control circuit 30 control board turns off the motor 21, and reports to the server; when the time from issuing the door opening command to receiving the door opening trigger signal from the door opening detection sensor 50 is greater than 4.2S, the anti-pinch is triggered, the control circuit 30 control board turns off the motor 21, so that when there is someone in front of the door body 10 during the door opening process, it can also prevent people from being pinched between the front of the door body 10 and the wall, etc.

[0060] Preferably, if Figure 4 As shown, the control circuit 30 also includes an emergency stop switch 34 electrically connected to the processor 31. The processor 31 is configured to stop the door from opening and closing based on a signal triggered by the emergency stop switch 34. In an emergency, simply pressing the emergency stop switch 34 causes the processor 31 to disconnect the power supply and shut down the motor 21 to prevent pinching.

[0061] Thus, in the electric door 100 of the present invention, there are multiple anti-pinch protection methods, including:

[0062] Pulse signal detection of infrared diffuse reflection sensor 40;

[0063] Current detection of the motor 21 by the current acquisition circuit 321;

[0064] Self-fracture protection of torque-limiting coupling;

[0065] Door opening and closing time timing coordinated by the door opening detection sensor 50 and the door closing detection sensor 60;

[0066] Emergency protection of emergency stop switch 34.

[0067] Multiple modes operate independently, and each mode can independently achieve anti-pinch protection after being triggered. In this way, the electric door 100 of the present invention has multiple anti-pinch protection modes, making the anti-pinch protection more stable and reliable.

[0068] Specifically, if Figure 2 and Figure 3 As shown, the screw transmission mechanism 22 of this embodiment includes a base 221, a screw 222, a slider 223, and a connecting rod 224. In this embodiment, the base 221, the motor 21, the control circuit 30, and the power module 70 are all installed in a box 80.

[0069] The two ends of the screw rod 222 are rotatably mounted on the seat body 221. In this embodiment, there are two seat bodies 221 that are spaced apart and arranged opposite to each other. A bearing is provided on each seat body 221. The two ends of the screw rod 222 are respectively mounted on the bearings of the two seat bodies 221 so that the seat body 221 can rotate.

[0070] One end of the screw rod 222 passes through the seat body 221 and is connected to the coupling 20. Figure 3 As shown in FIG, the right end of the screw rod 222 passes through the right seat body 221 and is connected to the coupling 20. The screw rod 222 also passes through the slider 223 and is threadedly connected to the slider 223. The slider 223 is provided with a screw hole, and the screw rod 222 is provided with a thread. The thread on the screw rod 222 is spirally connected to the screw hole of the slider 223. In this way, when the screw rod 222 rotates, the slider 223 will move linearly left and right on the screw rod 222.

[0071] One end of the connecting rod 224 is connected to the slider 223, and the other end of the connecting rod 224 is connected to the door body 10. Because one end of the connecting rod 224 is connected and fixed to the slider 223, when the slider 223 moves left and right, the connecting rod 224 moves left and right, thereby driving the door body 10 to move left and right to open and close the door.

[0072] like Figure 3As shown, preferably, the screw transmission mechanism 22 further includes a guide rod 225, both ends of which are mounted on the base 221. The guide rod 225 passes through the slider 223, and the slider 223 can slide relative to the guide rod 225. In this embodiment, the guide rod 225 is divided into two, which are respectively provided on the front and rear sides of the screw 222. The two ends of the guide rod 225 are respectively fixedly mounted on the two bases 221. At the same time, since the guide rods 225 are respectively passed through the front and rear sides of the slider 223, the slider 223 is guided and supported by the guide rods 225 during movement, which can ensure that the slider 223 can move stably on the screw 222.

[0073] The motor drive module 32 of the present invention includes a drive chip 322 connected to the processor 31 and the motor 21. The drive chip 322 is used to drive the motor to start, rotate forward and reverse according to the control signal of the processor 31.

[0074] like Figure 6 As shown, the current acquisition circuit 321 includes a sampling resistor 3211, a first sampling pin 3212 provided on the driver chip 322, and a second sampling pin 3213 provided on the processor 21. One end of the sampling resistor 3211 is connected to the first sampling pin 3212 and the second sampling pin 3213, and the other end is grounded. The first sampling pin 3212 is used to acquire the voltage at the end of the sampling resistor 3211. The driver chip 322 then controls the output current of the driver pin 3215 based on the comparison of the voltage with the reference voltage to control the power of the motor 21. The second sampling pin 3212 is used to acquire the voltage at the end of the sampling resistor 3211. The processor 31 then converts the voltage into a current value and compares it with a preset current value. When the actual acquired current value is greater than the preset value, the anti-pinch function is triggered, and the processor 31 shuts down the motor 21.

[0075] Specifically, if Figure 7 As shown, the driving chip 322 of this embodiment is LV8760T, which is provided with two driving pins 3215 OUTA and OUTB respectively connected to the plug J5, and the J5 tap is used to connect to the motor 21.

[0076] The RNF pin of the driver chip 322 is a first sampling pin 3212, connected to one end of R34, which is a sampling resistor 3211. The other end of R34 is grounded and connected to the 12V drive power supply of the driver chip 322 via capacitor C23. The VREF, IN1, and IN2 pins of the driver chip 322 are connected to corresponding pins of the processor 31. VREF provides a reference voltage for controlling the power of the motor 21. R34 is also connected to the second sampling pin 3213 of the processor 31, which is used to collect the voltage of the sampling resistor 3211. The processor 31 performs voltage-to-current conversion and current comparison to monitor the current of the motor 21 during operation. If a stall occurs, the motor is promptly shut down to prevent pinching.

[0077] Preferably, if Figure 6 and use Figure 7 As shown, a current limiting resistor 3214 is connected in series between the sampling resistor 3211 and the second sampling pin 3213. The current limiting resistor 3214 is Figure 7 R29 is used to limit the current on the sampling resistor 3211 to avoid affecting the second sampling pin 3213 of the processor 31.

[0078] The shielded box anti-pinch electric door 100 of the present invention realizes multiple anti-pinch measures by setting a current acquisition circuit 321, an infrared diffuse reflection sensor 40, a torque limiting coupling, a door opening and closing time timing, an emergency stop switch 34, etc., thereby improving the safety of the shielded box anti-pinch electric door 100.

[0079] The above description is merely an example to clearly illustrate the present invention and does not limit the patent scope of the present invention. It is impossible to list all implementation methods here. All equivalent structural transformations made by utilizing the contents of the technical solution of the present invention under the concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A shielded box anti-pinch electric door, comprising a door body, a drive mechanism, and a control circuit, characterized in that: The driving mechanism includes a motor, a screw transmission mechanism, and a coupling connected between the motor and the screw transmission mechanism, and the screw transmission mechanism is connected to the door body; The control circuit includes a processor and a motor drive module electrically connected to the processor; The motor drive module is electrically connected to the motor, and the motor drive module is provided with a current acquisition circuit for acquiring the current magnitude of the motor during the door opening and closing process; The screw drive mechanism is also provided with an infrared diffuse reflection sensor electrically connected to the processor, for collecting pulse signals of the screw drive mechanism during the door opening and closing process; The processor is used to determine whether a foreign object is clamped during the door opening and closing process according to the current size or the pulse signal and stop the door opening and closing.

2. The shielding box anti-pinch electric door according to claim 1, characterized in that: The coupling is a torque limiting coupling.

3. The shielding box anti-pinch electric door according to claim 1, characterized in that: The motor is a brushed DC motor.

4. The shielding box anti-pinch electric door according to claim 1, characterized in that: A door opening detection sensor and a door closing detection sensor are respectively provided at both ends of the screw drive mechanism in the direction of movement; The control circuit further includes a timing module electrically connected to the processor; The timing module is used to calculate the door opening and closing time after the door opening detection sensor and the door closing detection sensor are triggered, and the processor is used to determine whether there is a foreign object clamped during the door opening and closing process based on the door opening and closing time and stop opening and closing the door.

5. The shielding box anti-pinch electric door according to claim 1, characterized in that: The control circuit further includes an emergency stop switch electrically connected to the processor, and the processor is configured to stop opening and closing the door according to a signal after the emergency stop switch is triggered.

6. The shielding box anti-pinch electric door according to claim 1, characterized in that: The screw transmission mechanism includes a base, a screw, a slider, and a connecting rod; Both ends of the screw rod are rotatably mounted on the base body, and one end of the screw rod passes through the base body and is connected to the coupling; The screw rod also passes through the slider and is threadedly connected to the slider; One end of the connecting rod is connected to the sliding block, and the other end of the connecting rod is connected to the door body.

7. The shielding box anti-pinch electric door according to claim 6, characterized in that: The screw transmission mechanism further comprises a guide rod, both ends of which are mounted on the base body, the guide rod passes through the slider, and the slider can slide relative to the guide rod.

8. The shielding box anti-pinch electric door according to claim 1, characterized in that: The motor drive module includes a drive chip connected to the processor and the motor; The current acquisition circuit includes a sampling resistor, a first sampling pin provided on the driver chip, and a second sampling pin provided on the processor; One end of the sampling resistor is connected to the first sampling pin and the second sampling pin, and the other end is grounded.

9. The shielding box anti-pinch electric door according to claim 8, characterized in that: A current-limiting resistor is further connected in series between the sampling resistor and the second sampling pin.

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