CN210041379U

CN210041379U - Automatic charger for laser pointer in multimedia classroom

Info

Publication number: CN210041379U
Application number: CN201920966828.0U
Authority: CN
Inventors: 刘立权; 孙建迎; 殷桂堂
Original assignee: Shandong Agricultural University
Current assignee: Shandong Agricultural University
Priority date: 2019-06-26
Filing date: 2019-06-26
Publication date: 2020-02-07
Anticipated expiration: 2029-06-26

Abstract

The utility model discloses an automatic charger of multimedia classroom laser teacher's pointer is provided with a baffle in the casing of this charger, and the baffle divide into first cavity and second cavity with it, is provided with charging device in the first cavity, is the laser teacher's pointer charging tank in the second cavity, is equipped with the charging electrode assembly on the baffle. After the teacher uses the laser pointer, the teacher is inserted into a charging groove of the automatic charger, and the charging contact on the laser pointer can correspondingly contact with the charging electrode assembly, so that automatic charging is realized. In the charging process, the automatic charger can carry out automatic judgement according to the different conditions of laser teacher's pointer battery voltage in order to adjust the charged state, avoids the overheated and damage of battery. The charger avoids frequent replacement of the laser pointer battery, ensures the sufficient electric quantity of the laser pointer battery, and can be continuously and normally used, thereby effectively ensuring the multimedia teaching of teachers.

Description

Automatic charger for laser pointer in multimedia classroom

Technical Field

The utility model relates to a teaching equipment technical field, concretely relates to automatic charger of multimedia classroom laser teacher's pointer.

Background

The laser pointer is an important tool for teachers to finish classroom multimedia teaching, is a component of multimedia classroom teaching equipment, and consists of a laser pointer emitter (laser pointer) and a receiver. When the laser pointer is used, the receiver is inserted into a USB port of a computer, and related keys of the laser pointer are randomly pressed in the hand to realize functions of light spot screen indication, page turning and the like. Laser ferule generally uses battery No. 7, is light in weight but has a limited capacity, which adds difficulty to the multimedia device management work of colleges and universities. As the laser pointer is used more frequently and used for a longer time in college teaching, the battery of the laser pointer is consumed too fast, and the laser pointer needs to be replaced frequently (every two days). This will inevitably become a heavy burden for colleges with dozens or even hundreds of multimedia classrooms, and further affect the efficiency of multimedia teaching.

In the management to the laser teacher's pointer, because laser teacher's pointer transmitter and receiver are a one-to-one mode, and the receiver is not convenient for pull out and insert, consequently adopt the mode that alone one person was a pen easily to produce because of the receiver constantly pulls out and inserts and cause damage and thoughtlessly take the problem, so one set of laser teacher's pointer is installed in every classroom of carrying out general mode to avoid interface damage and receiver to thoughtlessly take the problem. This mode requires the management service staff to change the rechargeable battery at regular time and concentration, and the teacher needs to get the laser pointer of the corresponding classroom at a designated place before class, all of which bring inconvenience to the preparation of the teacher before class. Meanwhile, as the rechargeable battery is frequently replaced, the battery cabin cover of the laser pointer is easily damaged and lost, so that the laser pointer cannot be normally used.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a solve above-mentioned technical problem, proposed following technical solution:

in a first aspect, the embodiment of the utility model provides an automatic charger of multimedia classroom laser teacher's pointer, including charger shell, be provided with a baffle in the casing, the baffle will charger shell divide into first cavity and second cavity, be provided with charging device in the first cavity, be equipped with the electrode assembly that charges on the baffle, the electrode assembly that charges with the charging device electricity is connected, the second cavity is the laser teacher's pointer groove that charges, works as the laser teacher's pointer inserts when the second cavity is internal, the contact that charges of laser teacher's pointer with the electrode assembly that charges corresponds the contact.

By adopting the implementation mode, when the teacher uses the laser pointer, the laser pointer is inserted into the laser pointer charging groove of the automatic charger, and automatic charging of the laser pointer is realized. Therefore, the laser pointer is not required to be frequently replaced, and the battery power of the laser pointer is sufficient, so that the preparation time before class is saved for teachers, and the smooth teaching is guaranteed.

With reference to the first aspect, in a first possible implementation manner of the first aspect, the charging electrode assembly includes a first charging electrode contact piece and a second charging electrode contact piece, and a distance between charging ends of the first charging electrode contact piece and the second charging electrode contact piece is the same as a distance between charging contacts of the laser pointer.

With reference to the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, a shape of a laser pointer socket of the second cavity is the same as a cross-sectional shape of the laser pointer.

With reference to the first possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, a limiting plate is disposed in the second cavity, and distances from the bottom surface of the limiting plate to the first charging electrode contact piece and the second charging electrode contact piece are respectively the same as distances from the insertion end of the laser pointer to the two charging contacts.

With reference to the first aspect, in a fourth possible implementation manner of the first aspect, the charger further includes a charger back plate, and the charger housing is fixedly disposed on the charger back plate.

With reference to the first aspect or any one of the first to the fourth possible implementation manners of the first aspect, in a fifth possible implementation manner of the first aspect, the charging device includes: the switch power supply and switch linkage circuit, the charging and charging display circuit and the display drive circuit in place, the signal input end of the switch power supply and switch linkage circuit is electrically connected with an external power supply, the signal output end of the switch power supply and switch linkage circuit is electrically connected with the signal input end of the charging and charging display circuit, and the charging and charging display circuit is respectively electrically connected with the charging electrode assembly and the display drive circuit in place.

With reference to the fifth possible implementation manner of the first aspect, in a sixth possible implementation manner of the first aspect, the switching power supply and switch linkage circuit includes a self-recovery temperature fuse and a micro switch, a first end of the self-recovery temperature fuse and a first end of the micro switch are both electrically connected to the external power supply, a second end of the self-recovery temperature fuse is electrically connected to a first end of the filter inductor, a second end of the micro switch is electrically connected to a second end of the filter inductor, a third end of the filter inductor is electrically connected to a first end of the first capacitor and a first end of the rectifier bridge, a fourth end of the filter inductor is electrically connected to a second end of the first capacitor and a second end of the rectifier bridge, and a third end of the rectifier bridge is electrically connected to a first end of the second capacitor, a first end of the first resistor, and a first end of the second resistor, respectively, A first end of a third capacitor is electrically connected with a first end of a switch transformer, a fourth end of the rectifier bridge is respectively electrically connected with a second end of the second capacitor, a first end of a third resistor, a first end of a fourth capacitor, a first pin of a first chip, a first end of a fifth capacitor, a second end of the switch transformer and a first end of a sixth capacitor, a second end of the first resistor is electrically connected with a second pin of the first chip, a second end of the second resistor is respectively electrically connected with a second end of the third capacitor and a first end of a first diode, a second end of the first diode is respectively electrically connected with a third end of the switch transformer, a third pin and a fourth pin of the first chip, a second end of the third resistor is electrically connected with a fifth pin of the first chip, and a second end of the fourth capacitor is respectively electrically connected with a sixth pin of the first chip and a first end of the second diode, a second end of the second diode is electrically connected with a fourth end of the switch transformer, a second end of the fifth capacitor is electrically connected with a seventh pin of the first chip and a first end of the optocoupler respectively, and a second end of the optocoupler is electrically connected with a second end of the switch transformer; a fifth end of the switch transformer is electrically connected with a first end of a third diode, a sixth end of the switch transformer is electrically connected with a first end of a seventh capacitor and a first end of an eighth capacitor respectively, a second end of the third diode is electrically connected with a second end of the seventh capacitor, a first end of a fourth resistor and a first end of a first inductor respectively, a second end of the fourth resistor is connected with a first end of an LED indicating unit, a second end of the first inductor is electrically connected with a second end of the eighth capacitor and a first end of a fifth resistor, a second end of the fifth resistor is electrically connected with a first end of the sixth resistor and a third end of the optocoupler respectively, a fourth end of the optocoupler is electrically connected with a second end of the sixth resistor and a first end of the fourth diode respectively, and a second end of the sixth capacitor and a second end of the LED indicating unit respectively, and the second end of the seventh capacitor and the second end of the eighth capacitor are grounded, and the third end of the LED indicating unit and the second end of the first inductor are electrically connected with the charging and charging display circuit.

With reference to the sixth possible implementation manner of the first aspect, in a seventh possible implementation manner of the first aspect, the charging and charging display circuit includes a second chip, a first pin of the second chip is electrically connected to a second end of the first inductor, a second pin of the second chip is electrically connected to a first end of a second inductor, a second end of the second inductor is electrically connected to a third pin of the second chip and a first end of a fifth diode, respectively, a second end of the fifth diode is electrically connected to a first end of a ninth capacitor, a first end of a seventh resistor and an anode of a charging source, respectively, a second end of the ninth capacitor is grounded, a second end of the seventh resistor is electrically connected to a fourth pin of the second chip, and a cathode of the charging source is electrically connected to a first end of an eighth resistor and a fifth pin of the second chip, respectively, the second end of the eighth resistor is grounded, the sixth pin of the second chip is electrically connected with the third end of the LED indicating unit, the seventh pin and the eighth pin of the second chip are grounded, the first pin and the fifth pin of the second chip and the negative electrode of the charging power supply are also electrically connected with the in-place display driving circuit, and the positive electrode and the negative electrode of the charging power supply are also electrically connected with the charging electrode assembly respectively.

With reference to the seventh possible implementation manner of the first aspect, in an eighth possible implementation manner of the first aspect, the in-place display driving circuit includes a triode, a base of the triode is electrically connected to a first end of a ninth resistor and a first end of a tenth resistor, respectively, a second end of the ninth resistor is electrically connected to a first pin of the second chip, a first end of a sixth diode, and a first end of a relay, respectively, a second end of the tenth resistor is electrically connected to a fifth pin of the second chip and a cathode of the charging power supply, respectively, a collector of the triode is electrically connected to a second end of the sixth diode and a second end of the relay, respectively, and an emitter of the Q1 is grounded.

Drawings

Fig. 1 is a schematic structural diagram of an automatic charger for a laser pointer in a multimedia classroom according to an embodiment of the present invention;

fig. 2 is a schematic view of the laser pointer according to the embodiment of the present invention;

fig. 3 is a schematic diagram of a frame structure of a charging device according to an embodiment of the present invention;

fig. 4 is a schematic circuit structure diagram of a charging device according to an embodiment of the present invention;

in fig. 1 to 4, the symbols are represented as:

1-charger shell, 2-baffle, 3-first cavity, 4-second cavity, 5-charging device, 6-first charging electrode contact, 7-second charging electrode contact, 8-laser pointer socket, 9-limiting plate, 10-backboard, 11-commercial power connector, 12-upper cover fixing screw, 13-micro switch, 14-laser pointer, FUSE-self-recovery temperature FUSE, R1-first resistor, R2-second resistor, R3-third resistor, R4-fourth resistor, R5-fifth resistor, R6-sixth resistor, R7-seventh resistor, R8-eighth resistor, R9-ninth resistor, R10-tenth resistor, L0-inductive filtering, L1-first winding, l2-second winding, L3-third winding, L4-first inductor, L5-second inductor, C1-first capacitor, C2-second capacitor, C3-third capacitor, C4-fourth capacitor, C5-fifth capacitor, C6-sixth capacitor, C7-seventh capacitor, C8-eighth capacitor, C9-ninth capacitor, D1-first diode, D2-second diode, D3-third diode, D4-fourth diode, D5-fifth diode, D6-sixth diode, IC 1-first chip, IC 2-second chip, OC 1-BT-charging power supply, Q1-triode, J1-BT optical coupler.

Detailed Description

The present invention will be described with reference to the accompanying drawings and embodiments.

Fig. 1 is a schematic structural diagram of an automatic charger for a laser pointer in a multimedia classroom provided by an embodiment of the present invention. Referring to fig. 1, the automatic charger for the laser pointer in the multimedia classroom comprises a charger shell 1, in the embodiment, a transparent acrylic transparent plate with the thickness of 3 mm is adopted, a laser cutting machine is used for cutting and punching each component lath, and acrylic adhesive is used for gluing to obtain the charger shell 1. The inner cavity of the charger shell 1 is designed into a square box of 7.5cm x 11cm x 2 cm.

The charger is characterized in that a partition plate 2 is arranged in the shell, the charger shell 1 is divided into a first cavity 3 and a second cavity 4 by the partition plate 2, a charging device 5 is arranged in the first cavity 3, a charging electrode assembly is arranged on the partition plate 2, and the charging electrode assembly is electrically connected with the charging device 5.

As shown in fig. 2, the second cavity 4 is a laser pointer charging slot, and when the laser pointer 12 is inserted into the second cavity 4, the charging contact of the laser pointer 14 is correspondingly contacted with the charging electrode assembly.

Specifically, the charging electrode assembly comprises a first charging electrode contact piece 6 and a second charging electrode contact piece 7, and the distance between the charging ends of the first charging electrode contact piece 6 and the second charging electrode contact piece 7 is the same as the distance between the charging contacts of the laser pointer. In this embodiment, the charging electrode contact piece is a contact piece processed from 0.3 mm phosphor copper sheet into 0.6cm wide and 5.4cm long. Repeated experiments on the elasticity of the phosphor copper sheet show that the phosphor copper sheet can meet the requirement of contact force feeling. According to the position of the laser pointer battery, two square holes of 1cm x 0.7cm are punched on the partition board 2, and then the folded phosphor copper sheet is punched and installed. In order to ensure the installation stroke of the self-tapping screw, the partition plate 2 is pasted by a 2cm x 0.7cm acrylic strip lining thickness.

The shape of the laser pointer socket 8 of the second cavity 4 is the same as the cross-sectional shape of the laser pointer. Specifically, when the charger housing 1 is manufactured, the laser pointer socket 8 is designed according to the cross-sectional shape of the laser pointer, so that the laser pointer can be conveniently inserted into the sliding groove. For example, if a laser pointer of model N31, which is simple in structure, powerful, and easy to maintain, is used, the cross section of the laser pointer is trapezoidal, the panel operating portion is slightly wider, and the bottom portion is slightly narrower.

Specifically, for a laser pointer with a model of N31, the laser pointer socket 8 is designed into a trapezoidal hole, and the trapezoidal hole is 2.1cm at the upper side, 1.8cm at the bottom side and 1.6cm in height. Considering the power switch key on the left side wall of the laser pointer, the length of the chute part is equal to the length of the pen body below the power key of the laser pointer, so as to prevent the key from being clamped by the pointer socket 8. According to the length of the key-free part of the laser pointer pen body, the length of the sliding groove is 8 cm. Therefore, in this embodiment, a limiting plate 9 is disposed in the second cavity 4, a distance between the bottom surface of the limiting plate 9 and the first charging electrode contact and a distance between the bottom surface of the limiting plate 9 and the second charging electrode contact are respectively the same as a distance between the laser pointer insertion end and the two charging contacts, and the limiting plate 9 limits the insertion depth of the laser pointer and simultaneously supports the partition plate 2 to move rightward.

Because the cross-section of the laser pointer is trapezoidal, the two sides of the second cavity 4 are obliquely fixed by acrylic strips according to the body shape of the laser pointer, and a 2 x 11cm acrylic strip is added in the outer frame strip on the right side to be obliquely fixed, so that a sliding groove space matched with the laser pointer is manufactured. In order to prevent the laser pointer from being too close to the charging box bottom plate and leading to inconvenient pulling and inserting, an acrylic cushion strip is added on the upper part of the bottom plate, so that the pen body leaves the charging box bottom plate. In order to make the apron be difficult to the aversion, polish apron four sides 45 degrees angles, four frame strips of the box portion that charges also polish at its upper portion 45 degrees angles. Considering the problem of beauty, the four edge strip connection parts are also subjected to 45-degree angle polishing treatment

In order to facilitate the installation of the circuit board, a part of gasket is added in the first cavity 3, and the positions of the gasket are reasonably arranged by combining the stress of the circuit board components of the charging device 5. When the micro switch is used, the increase of a micro switch cushion block is also considered so as to be convenient for fixing the micro switch.

The laser pointer automatic charger provided by the embodiment further comprises a charger back plate 10, and the charger shell 1 is fixedly arranged on the charger back plate 10. The back plate 10 is perforated to facilitate mounting and fixing. The charger housing 1 is perforated at opposite positions to facilitate the feeding of the wire. Still be provided with commercial power connector 11, upper cover set screw 12 and micro-gap switch 13 in charger casing 1, commercial power connector 11 is connected with charging device 5 electricity for insert external power source, when the laser pen teacher's pointer inserts second cavity 4, through micro-gap switch 13 automatic switch-on commercial power, charge through charging device 5. The charger also comprises an upper cover when being installed, and the upper cover is fixed with the charger shell 1 only by one upper cover fixing screw 12.

As shown in fig. 3, the charging device 5 includes: the device comprises a switching power supply, a switching linkage circuit, a charging and charging display circuit and an in-place display driving circuit. The signal input end of the switch power supply and switch linkage circuit is electrically connected with an external power supply, the signal output end of the switch power supply and switch linkage circuit is electrically connected with the signal input end of the charging and charging display circuit, and the charging and charging display circuit is respectively electrically connected with the charging electrode assembly 6 and the on-site display driving circuit.

Further, referring to fig. 4, the switching power supply and switching linkage circuit includes a self-healing temperature FUSE and a micro switch K, a first end of the self-healing temperature FUSE and a first end of the micro switch K are both electrically connected to the external power supply, a second end of the self-healing temperature FUSE is electrically connected to a first end of a filter inductor L0, a second end of the micro switch K is electrically connected to a second end of the filter inductor L0, a third end of the filter inductor L0 is electrically connected to a first end of a first capacitor C1 and a first end of a rectifier bridge, respectively, a fourth end of the filter inductor L0 is electrically connected to a second end of a first capacitor C1 and a second end of the rectifier bridge, respectively, and a third end of the rectifier bridge is electrically connected to a first end of a second capacitor C2, a first end of a first resistor R1, a first end of a second resistor R2, a first end of a third capacitor C3 and a first end of a switching transformer, a fourth end of the rectifier bridge is electrically connected to a second end of the second capacitor C2, a first end of a third resistor R3, a first end of a fourth capacitor C4, a first pin of a first chip IC1, a first end of a fifth capacitor C5, a second end of the switch transformer, and a first end of a sixth capacitor C6, a second end of the first resistor R1 is electrically connected to a second pin of the first chip IC1, a second end of the second resistor R2 is electrically connected to a second end of the third capacitor C3 and a first end of a first diode D1, a second end of the first diode D1 is electrically connected to a third end of the switch transformer, a third pin of the first chip IC 3, a second end of the third resistor R3 is electrically connected to a fifth pin of the first chip IC1, a second end of the fourth capacitor C4 is electrically connected to a first end of a sixth diode D2 of the first chip IC1 and a second end of the second chip IC2, a second end of the second diode D2 is electrically connected to a fourth end of the switching transformer, a second end of the fifth capacitor C5 is electrically connected to a seventh pin of the first chip IC1 and a first end of an optocoupler OC1, and a second end of the optocoupler OC1 is electrically connected to a second end of the switching transformer.

A fifth terminal of the switching transformer is electrically connected to a first terminal of a third diode D3, a sixth terminal of the switching transformer is electrically connected to a first terminal of a seventh capacitor C7 and a first terminal of an eighth capacitor C8, respectively, a second terminal of the third diode D3 is electrically connected to a second terminal of a seventh capacitor C7, a first terminal of a fourth resistor R4, and a first terminal of a first inductor L4, respectively, a second terminal of the fourth resistor R4 is connected to a first terminal of an LED indication unit, a second terminal of the first inductor L4 is electrically connected to a second terminal of an eighth capacitor C8 and a first terminal of a fifth resistor R5, a second terminal of the fifth resistor R5 is electrically connected to a first terminal of a sixth resistor R6 and a second terminal of the optical coupler OC1, a fourth terminal of the optical coupler OC1 is electrically connected to a second terminal of the sixth resistor R6 and a first terminal of a fourth diode D4, respectively, and a second terminal of the fourth diode D4 is electrically connected to a second terminal of the sixth capacitor C3536 and a second terminal of the LED indication unit 6, the second end of the seventh capacitor C7 and the second end of the eighth capacitor C8 are grounded, and the third end of the LED indicating unit and the second end of the first inductor L4 are electrically connected with the charging and charging display circuit.

The charging and charging display circuit comprises a second chip IC2, a first pin of the second chip IC2 is electrically connected with a second end of the first inductor L4, a second pin of the second chip IC2 is electrically connected with a first end of a second inductor L5, a second end of the second inductor L5 is electrically connected with a third pin of the second chip IC2 and a first end of a fifth diode D5 respectively, a second end of the fifth diode D5 is electrically connected with a first end of a ninth capacitor C9, a first end of a seventh resistor R7 and a positive electrode of a charging power supply BT respectively, a second end of the ninth capacitor C9 is grounded, a second end of the seventh resistor R7 is electrically connected with a fourth pin of the second chip IC2, a negative electrode of the charging power supply BT is electrically connected with a first end of an eighth resistor R8 and a fifth pin of the second chip IC2 respectively, and a second end of the eighth resistor R8 is grounded, a sixth pin of the second chip IC2 is electrically connected to a third end of the LED indication unit, a seventh pin and an eighth pin of the second chip IC2 are grounded, the first pin and the fifth pin of the second chip IC2 and a negative electrode of the charging power supply BT are further electrically connected to the in-place display driving circuit, and a positive electrode and a negative electrode of the charging power supply BT are further electrically connected to the charging electrode assembly 6, respectively.

The in-place display driving circuit comprises a triode Q1, the base of the triode Q1 is electrically connected with the first end of a ninth resistor R9 and the first end of a tenth resistor R10 respectively, the second end of the ninth resistor R9 is electrically connected with the first pin of the second chip IC2, the first end of a sixth diode D6 and the first end of a relay J1 respectively, the second end of the tenth resistor R10 is electrically connected with the fifth pin of the second chip IC2 and the cathode of the charging power supply BT respectively, the collector of the triode Q1 is electrically connected with the second end of the sixth diode D6 and the second end of the relay J1 respectively, and the emitter of the triode Q1 is grounded.

The charging device circuit in the embodiment adopts a switching power supply mode, and the power supply switching circuit is simple and stable and is convenient to manufacture and produce. The switching power supply with the core of DK1203 is adopted, the first chip IC1 is a DK1203 power supply chip, 12W power is output to the maximum, a voltage-withstanding 700V switching tube is arranged in the module, the module has automatic protection functions of overload, overheating, overcurrent, overload and the like, a power supply circuit is built in the module, the module can work reliably even without feedback of an auxiliary winding and a driving resistor, peripheral elements are few, static consumption is low, and the module is a high-performance low-power switching power supply integrated circuit. A second chip IC2 in the charging circuit adopts novel power supply management CJC5122, the chip has the function of perfecting the charging process management of the nickel-metal hydride battery, the peripheral circuit is simple in structure and low in cost, the maximum charging current can reach 1A, peripheral resistance parameters are set, charging currents with different sizes can be provided, the charging circuit is an excellent charging power supply management chip, and the alternating input current of the whole charging device is not more than 1 milliampere when the charging device is in no-load.

In the embodiment, an alternating current power supply signal of 220V of an external power supply is input through a self-recovery temperature Fuse and a microswitch K, is subjected to interference resistance through a filter inductor L0 and a first capacitor C1, and is filtered through a bridge rectifier formed by diodes and a second capacitor C2 to obtain 290V direct current high voltage, the power supply is designed to have a rated power of 10W, a rated alternating current is about 55 milliamperes, and a recoverable Fuse takes 60 milliamperes.

The micro-motion design of the micro-switch K is linked with a charging electrode contact, and the micro-switch can be pushed by inserting the laser pointer to switch on a 220V alternating current power supply. The first chip IC1 is an off-line switching power supply module, when the power supply is switched on, 290V voltage charges the fourth capacitor C4 through an internal circuit, an oscillating circuit inside the IC1 works, a switching circuit enters a working state, considering that the TXC203 switching power supply chip is compatible, a first resistor R1 is additionally arranged to be used as a starting resistor, a second diode D2 is used for supplying power to a winding for rectification, and a third resistor R3 is used for current detection, if the DK1203 or above element is used, the current detection is omitted. DK1203 can not add starting resistor, is started by internal starting circuit self-starting, and the oscillation frequency is about 65KHZ, and opto-coupler QC1 is through first chip IC1 to internal pulse width duty cycle control, and second resistance R2, third electric capacity C3, first diode D1 are used for absorbing switching transformer B1 primary anti-peak wave, reduce the interference. The switching transformer B1 includes windings L1, L2 and a secondary winding L3, the secondary L3 output is rectified by a third diode D3, and the third diode D3 is a schottky rectifying diode.

The seventh capacitor C7, the eighth capacitor C8 and the first inductor L4 are used for filtering to obtain 5V output voltage, the selection ratio of the switch transformer B1 is large, the output current 2A is designed, and the requirements of laser pointer on-site display driving power are mainly considered besides charging consumption. The optical coupler OC1, the fourth diode D4, the fifth resistor R5 and the sixth resistor R6 form a voltage stabilizing circuit, the duty ratio of the switching power supply is automatically modulated through photosensitive conversion in the optical coupler, the stability of output voltage is further adjusted, and stable 5V working voltage is kept to be provided for the second chip IC 2. The fourth diode D4 is a zener diode, and the fifth resistor R5 and the sixth resistor R6 are current limiting resistors.

The opto-coupler OC1 also accomplishes the isolation of the primary thermoelectric from the output. The second chip IC2 is used as a charging management chip to charge the 1-4 nickel-metal hydride battery by the charging power supply BT. The integrated chip is internally provided with a 10-bit ADC (analog to digital converter), can perform digital-to-analog conversion on the voltage and current of a sampled battery, outputs a digital signal to an arithmetic logic unit, finishes automatic detection and judgment of the condition of the rechargeable battery, and provides charging schemes at different stages. The first pin of the IC2 is a power input pin, which is a +5V power input terminal, and the power input can work reliably within the range of 3.5V-7.5V.

The second pin is an internal P-channel field effect transistor drain output, the third pin is an internal N-channel field effect transistor drain input, the fourth pin is a charging current detection port, the fifth pin is a battery voltage detection port, the sixth pin is a charging LED display, and the four indication states of on/off, flash/slow flash are shared, and the four indication states respectively represent that the battery is not charged/full, and short circuit/normal charging is performed. The seventh pin is an internal reference ground for detecting the voltage condition of the rechargeable battery, and the eighth pin is a power ground.

The utility model discloses in according to 1 section nickel-hydrogen battery design, seventh resistance R7 is nickel-hydrogen output voltage pickup resistor, sets up seventh resistance R7 to 10K omega and makes the charging voltage value confirm at 1.2V. The ninth resistor R9 is a current value detection sampling resistor, the maximum charging current is 320MA when the value is 0.75 omega, the value is 1 omega considering 1 section of AAA battery, and the maximum charging current is not more than 250 MA. The second chip IC2 indicates excessive discharge when detecting that the battery is lower than 1V, small current is set inside to activate charging, the pre-charge value is 100MA, when detecting that the battery is higher than 1V, rapid charging is carried out, the maximum value is 250MA, in view of the nickel-hydrogen charging characteristic, after the battery charging voltage reaches the maximum value, the battery charging voltage drops to a few millivolt-delta V instantly, after the fifth pin of the second chip IC2 detects-delta V, supplementary charging is carried out, the internal preset time is 20 minutes, trickle charging is carried out after the charging is finished to compensate the self-discharge loss of the battery, the trickle charging current is 40MA, the trickle charging current can be maintained for a long time, and the safety requirement that the battery is not overheated is ensured. The second chip IC2 has a zero-volt battery activation circuit inside, and when the battery is first powered on to detect a short circuit, the battery is determined to be a zero-volt battery, and the battery is immediately activated, and then enters a normal charging process after activation. If the activation is not successful, the internal circuit of the IC2 is judged to be short-circuited, and the LED indicating unit flashes in red.

Regarding the realization of the high-low level output of the I/O control terminal, a triode Q1, a relay J1 and the like are added on the circuit board to form an I/O terminal circuit to realize the function. The triode Q1, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10 and other peripheral circuits form a high-sensitivity current detector, the eighth resistor R8 is a lower bias resistor and is also a current pickup resistor of the rechargeable battery, the ninth resistor R9 is an upper bias resistor, and the tenth resistor R10 is a lower bias resistor. When R8 is 1 ohm, the trickle is 40mA, the transistor Q1 can be conducted, and when the charging is pre-charged or charged by large current, the transistor Q1 is deeply conducted.

The current flowing through the relay J1 is about 5V/178 omega-28 ma, which is enough to drive the relay J1 to pull in, thereby realizing that the normally closed and open terminal of the relay J1 performs high and low level I/O output, and connecting the corresponding interface of the central control computer or other communication interfaces, so as to realize the on-site terminal display of the laser pointer. The sixth diode D6 is a relay on-off inverse peak voltage absorbing diode. When the rechargeable battery is not inserted, R8 basically has no current, the transistor Q1 is not conducted, and the relay J1 does not pull in. The output connection mode of the relay J1 is various, namely the normally closed fixed terminal of the relay J1 is connected with +5V, the output is high level after the attraction is carried out, the normally closed fixed terminal can be grounded in the reverse mode, and the low level is carried out after the attraction is carried out. Meanwhile, the fixed terminal can directly output the on-off function without being connected with the high and low levels of the power supply, the protocol module can be connected by the function, and the on-site state of the laser pointer can be observed through the internet. The power switch adopts a linkage microswitch mode, and the microswitch is pushed by the laser pointer when the laser pointer is inserted, so that the AC input power is switched on, and the long-time charged state of the circuit when the circuit is not charged is avoided.

The circuit displays the common-shade green-red LED as the working state, the red light turns to the 2HZ traffic light alternately after being turned on for 3 seconds to indicate that the power supply is switched on and is not charged, the traffic light alternately flashes slowly (1HZ) to indicate that the normal charging is carried out, the traffic light alternately flashes quickly (10HZ) to indicate that the charging output is short-circuited or the battery is not accordant, and the red light turns off the green light continuously and constantly to indicate that the battery is fully charged.

Component selection requirements: because the charger is in a charged working state for a long time, high-quality brand elements are required to be selected. The switch transformer is made of a commercially available finished product or can be made by self, (an EE19 ferrite magnetic core is used, a winding L1 is 88 turns of 0.21 enameled wire, a winding L2 is wound for 6 turns, a winding L3 is 6 turns of 0.41 wire), and a second capacitor C2 is electrolyzed by using small ruby with the voltage resistance of not less than 400V.

Known from the above embodiments, this embodiment provides an automatic charger of multimedia classroom laser teacher's pointer, and when the teacher used up the laser teacher's pointer, inserts the laser teacher's pointer into the laser teacher's pointer charging groove of automatic charger, realizes the automatic charging to the laser teacher's pointer. When charging, the charger can adjust the charged state according to the different conditions of battery voltage, prevents that the battery from leading to generating heat because of the charge time overlength. Need not to carry out the frequent change of battery to the laser teacher's pointer like this, also can guarantee that the battery electric quantity of laser teacher's pointer is sufficient, and then guaranteed the normal use of laser teacher's pointer.

It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Of course, the above description is not limited to the above examples, and technical features of the present invention that are not described in the present application may be implemented by or using the prior art, and are not described herein again; the above embodiments and drawings are only used for illustrating the technical solutions of the present invention and are not intended to limit the present invention, and if it is replaced, the present invention is only combined with and described in detail with reference to the preferred embodiments, and those skilled in the art should understand that changes, modifications, additions or substitutions made by those skilled in the art within the spirit of the present invention should also belong to the protection scope of the claims of the present invention.

Claims

1. The utility model provides an automatic charger of multimedia classroom laser teacher's pointer, its characterized in that, includes charger housing (1), be provided with a baffle (2) in the casing, baffle (2) will charger housing (1) divide into first cavity (3) and second cavity (4), be provided with charging device (5) in first cavity (3), be equipped with the electrode assembly that charges on baffle (2), the electrode assembly that charges with charging device (5) electricity is connected, second cavity (4) are the laser teacher's pointer groove that charges, works as the laser teacher's pointer inserts when in second cavity (4), the contact that charges of laser teacher's pointer with the electrode assembly that charges corresponds the contact.

2. The automatic charger for laser pointer in multimedia classroom according to claim 1, wherein said charging electrode assembly comprises a first charging electrode contact (6) and a second charging electrode contact (7), the distance between the charging ends of said first charging electrode contact (6) and said second charging electrode contact (7) being the same as the distance between the charging contacts of said laser pointer.

3. The automatic multimedia classroom laser pointer charger as defined in claim 2, wherein the laser pointer socket (8) of the second chamber (4) has the same shape as the cross-sectional shape of the laser pointer.

4. The automatic charger for laser pointer in multimedia classroom according to claim 2 characterized in that a limiting plate (9) is installed inside the second cavity (4), the distance between the bottom of the limiting plate (9) and the first charging electrode contact and the second charging electrode contact is the same as the distance between the insertion end of the laser pointer and the two charging contacts.

5. The automatic charger for laser pointer in multimedia classroom according to claim 1, further comprising a charger back plate (10), wherein the charger housing (1) is fixedly disposed on the charger back plate (10).

6. The automatic charger for laser pointer in multimedia classroom according to any of claims 1-4 wherein said charging device (5) comprises: the switch power supply and switch linkage circuit, the charging and charging display circuit and the display drive circuit in place, the signal input end of the switch power supply and switch linkage circuit is electrically connected with an external power supply, the signal output end of the switch power supply and switch linkage circuit is electrically connected with the signal input end of the charging and charging display circuit, and the charging and charging display circuit is respectively electrically connected with the charging electrode assembly and the display drive circuit in place.

7. The automatic charger for laser pointer in multimedia classroom according to claim 6, wherein said switching power supply and switching linkage circuit comprises a self-healing temperature fuse and a micro switch, a first end of said self-healing temperature fuse and a first end of said micro switch are both electrically connected to said external power supply, a second end of said self-healing temperature fuse is electrically connected to a first end of a filter inductor, a second end of said micro switch is electrically connected to a second end of said filter inductor, a third end of said filter inductor is electrically connected to a first end of a first capacitor and a first end of a rectifier bridge, a fourth end of said filter inductor is electrically connected to a second end of a first capacitor and a second end of a rectifier bridge, a third end of said rectifier bridge is electrically connected to a first end of a second capacitor, a first end of a first resistor, a first end of a second resistor, a first end of a third capacitor and a first end of a switching transformer, a fourth end of the rectifier bridge is electrically connected with a second end of the second capacitor, a first end of the third resistor, a first end of the fourth capacitor, a first pin of the first chip, a first end of the fifth capacitor, a second end of the switch transformer and a first end of the sixth capacitor, a second end of the first resistor is electrically connected with a second pin of the first chip, a second end of the second resistor is electrically connected with a second end of the third capacitor and a first end of the first diode, a second end of the first diode is electrically connected with a third end of the switch transformer, a third pin and a fourth pin of the first chip, a second end of the third resistor is electrically connected with a fifth pin of the first chip, a second end of the fourth capacitor is electrically connected with a sixth pin of the first chip and a first end of the second diode, respectively, and a second end of the second diode is electrically connected with a fourth end of the switch transformer, a second end of the fifth capacitor is electrically connected with a seventh pin of the first chip and a first end of an optocoupler respectively, and a second end of the optocoupler is electrically connected with a second end of the switch transformer;

a fifth end of the switch transformer is electrically connected with a first end of a third diode, a sixth end of the switch transformer is electrically connected with a first end of a seventh capacitor and a first end of an eighth capacitor respectively, a second end of the third diode is electrically connected with a second end of the seventh capacitor, a first end of a fourth resistor and a first end of a first inductor respectively, a second end of the fourth resistor is connected with a first end of an LED indicating unit, a second end of the first inductor is electrically connected with a second end of the eighth capacitor and a first end of a fifth resistor, a second end of the fifth resistor is electrically connected with a first end of the sixth resistor and a third end of the optocoupler respectively, a fourth end of the optocoupler is electrically connected with a second end of the sixth resistor and a first end of the fourth diode respectively, and a second end of the sixth capacitor and a second end of the LED indicating unit respectively, and the second end of the seventh capacitor and the second end of the eighth capacitor are grounded, and the third end of the LED indicating unit and the second end of the first inductor are electrically connected with the charging and charging display circuit.

8. The automatic charger for laser pointer in multimedia classroom according to claim 7, wherein said charging and displaying circuit comprises a second chip, a first pin of said second chip is electrically connected to a second terminal of said first inductor, a second pin of said second chip is electrically connected to a first terminal of a second inductor, a second terminal of said second inductor is electrically connected to a third pin of said second chip and a first terminal of a fifth diode, respectively, a second terminal of said fifth diode is electrically connected to a first terminal of a ninth capacitor, a first terminal of a seventh resistor and a positive electrode of a charging power source, a second terminal of said ninth capacitor is grounded, a second terminal of said seventh resistor is electrically connected to a fourth pin of said second chip, a negative electrode of said charging power source is electrically connected to a first terminal of an eighth resistor and a fifth pin of said second chip, respectively, the second end of the eighth resistor is grounded, the sixth pin of the second chip is electrically connected with the third end of the LED indicating unit, the seventh pin and the eighth pin of the second chip are grounded, the first pin and the fifth pin of the second chip and the negative electrode of the charging power supply are also electrically connected with the in-place display driving circuit, and the positive electrode and the negative electrode of the charging power supply are also electrically connected with the charging electrode assembly respectively.

9. The automatic charger for laser pointer in multimedia classroom according to claim 8, wherein said display-in-place driving circuit comprises a triode, wherein the base of said triode is electrically connected to the first terminal of a ninth resistor and the first terminal of a tenth resistor, respectively, the second terminal of said ninth resistor is electrically connected to the first pin of said second chip, the first terminal of a sixth diode and the first terminal of a relay, the second terminal of said tenth resistor is electrically connected to the fifth pin of said second chip and the negative terminal of said charging power source, respectively, the collector of said triode is electrically connected to the second terminal of said sixth diode and the second terminal of said relay, respectively, and the emitter of said triode is grounded.