A test stylus having a light source

Abstract

This utility model discloses a test probe with a light source, comprising a plastic body, a probe needle inserted into a first end of the plastic body, and a test probe wire connected to a second end of the plastic body. A wire is disposed within the test probe wire and connected to the probe needle. A power module, a control module, a light source driving module, and a light-emitting module are embedded in the plastic body. The power module provides a power supply voltage VCC. The control module is electrically connected to the light source driving module, and the light source driving module is electrically connected to the light-emitting module. The light-emitting module is disposed at the first end of the plastic body, and the optical axis of the light-emitting module faces the extension direction of the probe needle. In this utility model, the test probe has a built-in light source, eliminating the need for an additional light source when the testing environment is dim, thus facilitating testing by personnel.

Description

Technical Field

[0001] This utility model belongs to the field of testing instruments, and in particular relates to a test probe with a light source. Background Technology

[0002] Modern electronic products are miniaturized, widely adopting small-sized components to reduce device size. Some components have lead dimensions of less than 0.15 mm and solder joints less than 0.2 mm. The probe tips of testing instruments (such as multimeters) used by testers (or repair personnel) are now less than 0.05 mm in size. In low light, testers may have difficulty seeing the solder joints, leading to inaccurate test results and the potential for short circuits between adjacent solder joints. In chip-level repair, external light sources are often added to increase the brightness of the solder joints being inspected, thus requiring the addition and adjustment of external light sources, which is time-consuming and costly. Furthermore, the use of external light sources can create shadows on the tester's hands and multimeter probes at the test site, further affecting the brightness of the test point. Utility Model Content

[0003] In view of the shortcomings of the prior art, the technical problem to be solved by this utility model is to provide a test probe with a light source.

[0004] To solve the above-mentioned technical problems, this utility model provides the following technical solution: A test probe with a light source includes a plastic body. A probe needle is inserted into a first end of the plastic body, and a probe wire is connected to a second end of the plastic body. A wire is provided in the probe wire and connected to the probe needle. A power module, a control module, a light source driving module, and a light-emitting module are embedded in the plastic body. The power module provides a power supply voltage VCC. The control module is electrically connected to the light source driving module, and the light source driving module is electrically connected to the light-emitting module. The light-emitting module is disposed at the first end of the plastic body, and the optical axis of the light-emitting module faces the extension direction of the probe needle.

[0005] Furthermore, the power module is defined as battery P1.

[0006] Furthermore, the power module also includes a switch K1, one end of which is connected to the positive terminal of the battery P1, and the other end is used to output the power supply voltage VCC.

[0007] Furthermore, the light source driving module includes resistors R4, R5, and R6, and a driving transistor Q1. The light-emitting module includes at least one light-emitting diode disposed at the first end of the plastic body. The positive terminal of each light-emitting diode is electrically connected to the first terminal of resistor R6, and the second terminal of resistor R6 is connected to the power supply voltage VCC. The negative terminal of each light-emitting diode is electrically connected to the collector of the driving transistor Q1. The base of the driving transistor Q1 is electrically connected to the first terminal of resistor R4, and the second terminal of resistor R4 is electrically connected to the control module. The base of the driving transistor Q1 is also grounded through resistor R5, and the emitter of the driving transistor Q1 is grounded.

[0008] Furthermore, the control module is defined as an infrared detection unit, and the output terminal of the infrared detection unit is used as the output terminal of the control module and electrically connected to the light source driving module.

[0009] Furthermore, the control module includes an infrared detection unit, a brightness detection unit, and an AND gate. The first input terminal of the AND gate is electrically connected to the output terminal of the infrared detection unit, the second input terminal of the AND gate is electrically connected to the output terminal of the brightness detection unit, and the output terminal of the AND gate is electrically connected to the light source driving module as the output terminal of the control module.

[0010] Furthermore, the infrared detection unit includes a thermal infrared sensor PIR, resistors R1, R2, R3, PR1, capacitor C1, and comparator U1.1. The thermal infrared sensor PIR is embedded in the plastic body, with its sensing terminal exposed on the surface of the plastic body. The first terminal of the thermal infrared sensor PIR is connected to the power supply voltage VCC through resistor R1, and the second terminal of the thermal infrared sensor PIR is grounded through resistor R3. The capacitor C1 is connected in parallel with resistor R3. The second terminal of the thermal infrared sensor PIR is also electrically connected to the non-inverting input terminal of comparator U1.1, and the third terminal of the thermal infrared sensor PIR is grounded. The inverting input terminal of comparator U1.1 is connected to the power supply voltage VCC through resistor R2, and the inverting input terminal of comparator U1.1 is also grounded through resistor PR1. The output terminal of comparator U1.1 forms the output terminal of the infrared detection unit.

[0011] Furthermore, the brightness detection unit includes resistors R7, PR2, and PR3, a comparator U1.2, and at least one photoresistor. The photoresistors are disposed at the first end of the plastic body. The non-inverting input terminal of the comparator U1.2 is electrically connected to the first end of each of the photoresistors, and the second end of each of the photoresistors is grounded. The non-inverting input terminal of the comparator U1.2 is also connected to the power supply voltage VCC through resistor PR3. The inverting input terminal of the comparator U1.2 is connected to the power supply voltage VCC through resistor R7, and the inverting input terminal of the comparator U1.2 is also grounded through resistor PR2. The output terminal of the comparator U1.2 forms the output terminal of the brightness detection unit.

[0012] Furthermore, both resistors PR2 and PR3 are adjustable resistors, and the photosensitive threshold can be adjusted by adjusting the resistance values ​​of resistors PR2 and PR3.

[0013] Furthermore, the comparator U1.1, comparator U1.2, AND gate, resistors R1, R2, R3, R4, R5, R6, R7, PR1, PR2, PR3, and driving transistor Q1 are all integrated on a flexible circuit board. A cavity is formed in the plastic body, and the flexible circuit board is placed in the cavity. A cover plate is provided at the opening of the cavity, and the cover plate is snapped into the opening of the cavity.

[0014] In this invention, the test probes have a built-in light source, eliminating the need for an additional light source when the testing environment is dim. The LEDs only illuminate when the tester is using the probes in low light conditions, precisely adapting to the application scenario and preventing the LEDs from remaining constantly lit. The control module is controlled by an AND gate, allowing for single-chip control without the need for additional logic chips. The overall circuit is built using resistors, capacitors, transistors, comparators, and AND gates, implemented entirely in hardware, resulting in high stability and low cost. Furthermore, the adjustable resistors allow for convenient adjustment of the infrared detection threshold and brightness threshold, ensuring good environmental adaptability. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This utility model discloses a schematic diagram of the structure of a test pen with a light source according to an embodiment.

[0016] Figure 2 This utility model discloses a circuit diagram of an embodiment of a test probe with a light source.

[0017] Figure 3This is a schematic diagram of the LED setup in Example 1.

[0018] Figure 4 This utility model discloses a circuit diagram of another embodiment of a test probe with a light source.

[0019] Figure 5 This is a schematic diagram of the setup of the light-emitting diode and photoresistor in Example 2.

[0020] The diagrams in the instruction manual are labeled as follows: Plastic body - 1; Pen needle - 2; Dial lead wire - 3; Wire - 4; Cavity - 5; Cover plate - 6; Flexible circuit board - 7; Light emission diode - 8, LED1, LED2, LED3, LED4; Photoresistor - 9, R9, R10, R11, R12; Rechargeable battery - P1; Thermal infrared sensor - PIR; Switch - K1; Power module - 100; Light source driver module - 200; Light emission module - 300; Infrared detection unit - 400; Brightness detection unit - 500; AND gate - 600. Detailed Implementation

[0021] The following specific examples illustrate the implementation of this utility model. The illustrations provided in the following embodiments are only schematic representations of the basic concept of this utility model. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0022] Example 1 Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of an embodiment of a test pen with a light source according to the present invention. The test pen with a light source in this embodiment includes a plastic body 1, a pen needle 2 inserted into the first end of the plastic body 1, and a test pen wire 3 connected to the second end of the plastic body 1. A wire 4 is disposed in the test pen wire 3, and the wire 4 is connected to the pen needle 2.

[0023] The plastic body 1 is embedded with a power module 100, a control module, a light source driving module 200, and a light-emitting module 300. The power module 100 is used to provide power voltage VCC to each unit. The power module 100 may include a battery P1. In this embodiment, the power module can be limited to the battery P1. The voltage of the battery P1 is preferably 5V, so that it can directly power the chips of each module without the need for an additional power chip for DC-DC conversion.

[0024] The power module 100 may further include a switch K1, one end of which is connected to the positive terminal of the battery P1, and the other end is used to output the power supply voltage VCC. In this embodiment, the switch K1 is a push-button switch, which can be located near the second end of the plastic body 1 to avoid accidental activation during operation. When the switch K1 is closed, the power unit outputs the power supply voltage VCC to power each module; when the switch K1 is open, the power unit does not output voltage to save power. Of course, the switch K1 can also be a toggle switch or other switches.

[0025] Please see Figure 2 The control module is electrically connected to the light source driving module 200 and is used to control the operation of the light source driving module 200. The light source driving module 200 is electrically connected to the light-emitting module 300 and is used to drive the light-emitting module 300 to emit light under the control of the control module. The light-emitting module 300 is disposed at the first end of the plastic body, and the optical axis of the light-emitting module 300 is oriented towards the extension direction of the pen needle 2, so as to illuminate the test points of the test probe.

[0026] The light source driving module 200 may include resistors R4, R5, and R6, and a driving transistor Q1. The driving transistor Q1 is preferably a surface-mount element, such as a BL8050. Similarly, resistors R4, R5, and R6 are also preferably surface-mount resistors. The light-emitting module 300 includes at least one light-emitting diode 8 disposed at the first end of the plastic body.

[0027] In this embodiment, the light-emitting module 300 includes four light-emitting diodes 8, namely LED1, LED2, LED3, and LED4. Please refer to... Figure 3 The light-emitting diodes (LEDs) LED1, LED2, LED3, and LED4 are evenly arranged circumferentially at the first end of the plastic body 1 to provide omnidirectional illumination. Preferably, the LEDs LED1, LED2, LED3, and LED4 are arranged at an angle, so that the optical axes of all LEDs LED1, LED2, LED3, and LED4 are directed towards the tip of the pen needle 2. This allows the tip of the test probe to be positioned within the light spot formed by the LEDs 8, achieving shadowless detection.

[0028] The positive terminals of LEDs LED1, LED2, LED3, and LED4 are all electrically connected to the first terminal of resistor R6, and the second terminal of resistor R6 is connected to the power supply voltage VCC. The negative terminals of LEDs LED1, LED2, LED3, and LED4 are all electrically connected to the collector of driver transistor Q1. The base of driver transistor Q1 is electrically connected to the first terminal of resistor R4, and the second terminal of resistor R4 is electrically connected to the control module. The base of driver transistor Q1 is also grounded through resistor R5, and the emitter of driver transistor Q1 is grounded.

[0029] In this embodiment, the control module is defined as an infrared detection unit 400, and the output terminal of the infrared detection unit 400 is used as the output terminal of the control module and electrically connected to the light source driving module 200.

[0030] The infrared detection unit 400 includes a thermal infrared sensor PIR, resistors R1, R2, R3, PR1, capacitor C1, and comparator U1.1. Resistors R1, R2, R3, and C1 are preferably surface-mount resistors and capacitors. The comparator U1.1 can be integrated onto a chip U1, which can be an LM393 chip. The thermal infrared sensor PIR is embedded in the plastic body 1, with its sensing terminal exposed on the surface of the plastic body 1. The thermal infrared sensor PIR is generally positioned within the hand grip area to detect whether the tester is holding the test leads. Resistor PR1 is an adjustable resistor used to adjust the infrared sensing activation threshold.

[0031] The first terminal of the thermal infrared sensor PIR is connected to the power supply voltage VCC through resistor R1, and the second terminal of the thermal infrared sensor PIR is grounded through resistor R3. The capacitor C1 is connected in parallel with resistor R3. The second terminal of the thermal infrared sensor PIR is also electrically connected to the non-inverting input terminal of comparator U1.1, and the third terminal of the thermal infrared sensor PIR is grounded. The inverting input terminal of comparator U1.1 is connected to the power supply voltage VCC through resistor R2, and the inverting input terminal of comparator U1.1 is also grounded through resistor PR1. The output terminal of comparator U1.1 forms the output terminal of infrared detection unit 400.

[0032] With switch K1 closed, the infrared detection unit 400 outputs a high level when a person holds the test probe and a low level when the person removes the test probe, and eliminates false triggering through simple RC filtering. When the tester holds the test probe, the infrared detection unit 400 outputs a high level, causing the light source driving module 200 to work and drive the four light-emitting diodes 8 to emit light.

[0033] In this embodiment, the chip U1, resistors R1, R2, R3, R4, R5, R6, PR1, and driving transistor Q1 are all integrated on a flexible circuit board 7. A cavity 5 is formed in the plastic body 1, and the flexible circuit board 7 and battery P1 are both disposed within the cavity 5. A cover plate 6 is provided at the opening of the cavity 5 to seal the opening. The cover plate 6 snaps into the opening of the cavity 5, and the cover plate 6 can have an arc-shaped structure to accommodate the shape of the probes. Alternatively, the cavity 5 can be directly filled using potting compound. Since most of the components in this embodiment are surface-mount components, and the other components are also very small, they can be integrated onto the flexible circuit board 7 and disposed entirely inside the plastic body 1, facilitating integration.

[0034] Example 2 Please see Figure 4 The difference between this embodiment and Embodiment 1 lies only in the structure of the control module. In this embodiment, the control module includes an infrared detection unit 400, a brightness detection unit 500, and an AND gate 600. The first input terminal of the AND gate 600 is electrically connected to the output terminal of the infrared detection unit 400, and the circuit structure of the infrared detection unit 400 can be the same as in Embodiment 1. The second input terminal of the AND gate 600 is electrically connected to the output terminal of the brightness detection unit 500, and the output terminal of the AND gate 600 serves as the output terminal of the control module and is electrically connected to the second terminal of the resistor R4 in the light source driving module 200.

[0035] The brightness detection unit 500 is used to detect the brightness of the front end of the test probe and may include resistors R7, PR2, PR3, comparator U1.2, and at least one photoresistor 9. Resistor R7 is preferably a surface-mount resistor. Resistors PR2 and PR3 are both adjustable resistors. Comparators U1.1 and U1.2 can both be integrated on chip U1. Chip U1 can be an LM393 chip, which integrates two comparators to meet the requirements. The photoresistor 9 is disposed at the first end of the plastic body, allowing it to be spaced apart from the light-emitting diode 8. In this embodiment, four photoresistors 9 are provided: photoresistor R9, photoresistor R10, photoresistor R11, and photoresistor R12. Please refer to [link to relevant documentation]. Figure 5 The photoresistors R9, R10, R11 and R12 are evenly arranged at the first end of the plastic body 1 along the circumferential direction and are spaced apart between the four light-emitting diodes 8.

[0036] The non-inverting input of comparator U1.2 is electrically connected to the first terminals of photoresistors R9, R10, R11, and R12, respectively. The second terminals of photoresistors R9, R10, R11, and R12 are all grounded. The non-inverting input of comparator U1.2 is also connected to the power supply voltage VCC through resistor PR3. The inverting input of comparator U1.2 is connected to the power supply voltage VCC through resistor R7. The inverting input of comparator U1.2 is also grounded through resistor PR2. The output of comparator U1.2 forms the output of the brightness detection unit 500.

[0037] In the brightness detection unit 500, the photoresistors 9 (i.e., photoresistors R9, R10, R11, and R12) and the fixed resistor (resistor PR3, whose resistance value is fixed during use) form a voltage divider circuit. The divided voltage is connected to the non-inverting input of comparator U1.2. The brightness threshold is set by adjusting the voltage divider resistor (i.e., adjusting resistor PR2) at the inverting input of comparator U1.2. When the brightness is sufficient, the voltage divided by photoresistors 9 is lower than the brightness threshold, and comparator U1.2 outputs a low level; when the brightness is insufficient, the voltage divided by photoresistors 9 is higher than the brightness threshold, and comparator U1.2 outputs a high level. The AND gate 600 can be integrated onto chip U2, which can be an SN74LN1G08 chip. When the tester holds the test probe, the thermal infrared sensor PIR detects an infrared signal, causing the output of comparator U1.2 to output a high level to the first input of AND gate 600. When the brightness detection unit 500 detects low brightness at the tip of the test probe, it determines that the light in the vicinity of the test point is weak, and the brightness detection unit 500 outputs a high level to the second input of AND gate 600. When both the infrared detection unit 400 and the brightness detection unit 500 output high levels, AND gate 600 outputs a high level, causing the light source driving module 200 to work and drive the four light-emitting diodes 8 to emit light. For specific scenarios, please refer to Table 1: Table 1

[0038] To ensure the control module does not output a low level when LED 8 is emitting light, the brightness threshold voltage can be appropriately increased. If the brightness around the tip of the test probe is brighter than when LED 8 is emitting light, the brightness detection unit 500 will output a low level, the control circuit will not output voltage, and the four LEDs 8 will not emit light. For example, when the daytime light is good and the ambient brightness is high, the brightness detection unit 500 will output a low level, and the four LEDs 8 will not emit light.

[0039] In this embodiment, the chip U1, chip U2, resistors R1, R2, R3, R4, R5, R6, R7, PR1, PR2, PR3 and driving transistor Q1 can all be integrated on the flexible circuit board 7.

[0040] In this embodiment, the test probes have a built-in light source, eliminating the need for an additional light source when the ambient light is dim. The LED 8 only illuminates when the test probes are in use and the surrounding light is low, precisely adapting to the usage scenario and preventing light pollution caused by the LED 8 remaining constantly lit. The control module is controlled by an AND gate 600, allowing for single-chip control (SN74LVC1G08) without the need for additional logic chips. The overall circuit is built using resistors, capacitors, transistors, comparators, and AND gates 600, employing pure hardware implementation for high stability and low cost. Furthermore, the adjustable resistors allow for convenient adjustment of the infrared detection threshold and brightness threshold, ensuring good environmental adaptability.

[0041] The above embodiments only illustrate preferred implementations of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A test probe with a light source, characterized in that: The device includes a plastic body, a pen needle inserted into a first end of the plastic body, and a test lead wire connected to a second end of the plastic body. A wire is provided in the test lead wire and connected to the pen needle. A power module, a control module, a light source driving module, and a light-emitting module are embedded in the plastic body. The power module provides a power supply voltage VCC. The control module is electrically connected to the light source driving module, and the light source driving module is electrically connected to the light-emitting module. The light-emitting module is located at the first end of the plastic body, and its optical axis faces the direction in which the pen needle extends.

2. A test tablet stylus having a light source as claimed in claim 1, wherein: The power module is defined as battery P1.

3. A test tablet stylus having a light source as claimed in claim 1, wherein: The power module also includes a switch K1, one end of which is connected to the positive terminal of the battery P1, and the other end is used to output the power supply voltage VCC.

4. A test tablet stylus having a light source as in claim 1, wherein: The light source driving module includes resistors R4, R5, and R6, and a driving transistor Q1. The light-emitting module includes at least one light-emitting diode disposed at the first end of the plastic body. The positive terminal of each light-emitting diode is electrically connected to the first terminal of resistor R6, and the second terminal of resistor R6 is connected to the power supply voltage VCC. The negative terminal of each light-emitting diode is electrically connected to the collector of the driving transistor Q1. The base of the driving transistor Q1 is electrically connected to the first terminal of resistor R4, and the second terminal of resistor R4 is electrically connected to the control module. The base of the driving transistor Q1 is also grounded through resistor R5, and the emitter of the driving transistor Q1 is grounded.

5. A test tablet stylus having a light source as defined in claim 1, wherein: The control module is defined as an infrared detection unit, and the output terminal of the infrared detection unit is used as the output terminal of the control module and electrically connected to the light source driving module.

6. A test tablet stylus having a light source as defined in claim 1, wherein: The control module includes an infrared detection unit, a brightness detection unit, and an AND gate. The first input terminal of the AND gate is electrically connected to the output terminal of the infrared detection unit, the second input terminal of the AND gate is electrically connected to the output terminal of the brightness detection unit, and the output terminal of the AND gate is electrically connected to the light source driving module as the output terminal of the control module.

7. A test tablet stylus having a light source as claimed in claim 6, wherein: The infrared detection unit includes a thermal infrared sensor PIR, resistors R1, R2, R3, PR1, capacitor C1, and comparator U1.

1. The thermal infrared sensor PIR is embedded in the plastic body, with its sensing terminal exposed on the surface of the plastic body. The first terminal of the thermal infrared sensor PIR is connected to the power supply voltage VCC through resistor R1, and the second terminal of the thermal infrared sensor PIR is grounded through resistor R3. The capacitor C1 is connected in parallel with resistor R3. The second terminal of the thermal infrared sensor PIR is also electrically connected to the non-inverting input terminal of comparator U1.1, and the third terminal of the thermal infrared sensor PIR is grounded. The inverting input terminal of comparator U1.1 is connected to the power supply voltage VCC through resistor R2, and the inverting input terminal of comparator U1.1 is also grounded through resistor PR1. The output terminal of comparator U1.1 forms the output terminal of the infrared detection unit.

8. A test tablet stylus having a light source as claimed in claim 7, wherein: The brightness detection unit includes resistors R7, PR2, and PR3, a comparator U1.2, and at least one photoresistor. The photoresistors are disposed at the first end of the plastic body. The non-inverting input of the comparator U1.2 is electrically connected to the first end of each of the photoresistors, and the second end of each of the photoresistors is grounded. The non-inverting input of the comparator U1.2 is also connected to the power supply voltage VCC through resistor PR3. The inverting input of the comparator U1.2 is connected to the power supply voltage VCC through resistor R7, and the inverting input of the comparator U1.2 is also grounded through resistor PR2. The output of the comparator U1.2 forms the output of the brightness detection unit.

9. A test tablet stylus having a light source as claimed in claim 8, wherein: Both resistors PR2 and PR3 are adjustable resistors, and the photosensitive threshold can be adjusted by adjusting the resistance values ​​of resistors PR2 and PR3.

10. A test tablet stylus having a light source as claimed in claim 9, wherein: The comparator U1.1, comparator U1.2, AND gate, resistors R1, R2, R3, R4, R5, R6, R7, PR1, PR2, PR3, and driver transistor Q1 are all integrated on a flexible circuit board. A cavity is formed in the plastic body, and the flexible circuit board is placed in the cavity. A cover plate is provided at the opening of the cavity, and the cover plate is snapped into the opening of the cavity.

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