A portable multi-channel polarity testing device

Abstract

The application relates to the technical field of polarity detection devices, and specifically provides a portable multi-channel polarity testing device which comprises a multimeter body and two test pens, the two test pens each have a pen body part and a pen tip part, the pen tip part comprises a fixed section and an extension section, a rubber sleeve is arranged on the outer periphery of the extension section, and the two ends of the rubber sleeve are fixed on the pen tip head and the fixed section; when the pen tip breaks, the rubber sleeve can wrap the broken pen tip residual section inside, avoids the residual section from flying out to damage the detection target or cause personal injury to the detection personnel; meanwhile, a plurality of elastic guide strips are arranged on the side wall of the rubber sleeve, the rubber sleeve and the plurality of elastic guide strips greatly improve the bending strength of the pen tip part; when the extension section is shortened, the elastic guide strips bend radially outward along the rubber sleeve and abut against the inner wall of the hole, the contact area is significantly increased, the interference of the elastic guide strips on the polarity detection data is reduced, and the accuracy of the detection result is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of polarity detection devices, in particular to a portable multi-channel polarity testing device. BACKGROUND

[0002] There are generally three methods for polarity measurement: one is direct current method, two is alternating current method, and three is instrument method. The alternating current method is generally not adopted because it is difficult to obtain power supply and has safety risks. The direct current method is generally used in the construction site. The instrument method is suitable for use in the transformer laboratory.

[0003] When the direct current method is used for detection, a direct current power supply (such as a 1.5V dry battery or a 9V stacked battery), a multimeter (placed in the direct current milliammeter or direct current microammeter) and a plurality of wires are needed. During detection, the instantaneous magnetic flux change caused by the direct current through the primary winding is used to realize detection, and the instantaneous electromotive force is induced in the secondary winding. The polarity is determined by the deflection direction of the multimeter pointer.

[0004] For example, Chinese patent CN210071917U discloses a multimeter pen. The scheme includes a first test pen tip and a second test pen tip of different sizes. The first test pen tip, which is thinner, can be used to measure precision electronic circuits or wiring arrays with fine apertures. The second test pen tip, which is thicker, is suitable for regular measurement and can meet the testing requirements of regular-sized components. When in use, the staff can reasonably select the first test pen tip or the second test pen tip for measurement according to the size of the component to be measured, thereby widening the versatility of the multimeter pen and enabling it to be widely used in various environments.

[0005] However, the pen tip of the above-mentioned multimeter pen may be bent or even broken after long-term use. In this case, the pen tip needs to be replaced, which affects the efficiency of detection. If the pen tip breaks, the broken pen tip will fly out and damage the detection target, and even the detection personnel may be injured. In addition, when testing a hole-type detection target, a cylindrical detection head is used. The size of the detection head is generally smaller than the diameter of the hole, which causes the detection head to not be tightly attached to the hole, increases the contact resistance, and affects the detection result. SUMMARY

[0006] Therefore, it is necessary to provide a portable multi-channel polarity testing device to solve the problems that the pen tip of the multimeter pen is easily bent or broken after long-term use, and the pen tip cannot be tightly attached to the hole, which affects the detection result.

[0007] The above-mentioned purpose is achieved by the following technical scheme:

[0008] A portable multi-channel polarity testing device comprises:

[0009] A multimeter body is provided with a display screen.

[0010] Two test leads are connected to the multimeter body, each having a lead body portion and a lead tip portion, the lead tip portion including a fixed segment and an extension segment, the extension segment having a lead tip end distal from the fixed segment, and a rubber sleeve being provided around the extension segment, the rubber sleeve having the lead tip end and the fixed segment fixedly connected thereto.

[0011] A plurality of elastic conductive strips are electrically connected to the lead tip end and the fixed segment, respectively, and are parallel to the axis of the rubber sleeve, and are uniformly distributed on the side wall of the rubber sleeve, the elastic conductive strips being elastic and conductive, and being configured to bend radially outwardly along the rubber sleeve when the extension segment is shortened, the degree of bending of the elastic conductive strips being positively correlated with the diameter of the hole.

[0012] Further, the extension segment includes a guide rod and an elastic member, the guide rod being slidingly inserted into the fixed segment, and the elastic member being located between the guide rod and the fixed segment, the elastic member having a tendency to push the guide rod out of the fixed segment.

[0013] Further, a sealed cavity is formed between the guide rod and the rubber sleeve, and the thickness of the rubber sleeve gradually decreases from the fixed segment to the lead tip end.

[0014] Further, a plurality of protrusions are formed on the side wall of the rubber sleeve and directed toward the axis of the rubber sleeve, and the elastic conductive strips are arranged in the protrusions, respectively, and gradually extend out of the rubber sleeve as the diameter of the rubber sleeve increases.

[0015] Further, the number of the protrusions is four, and the number of the elastic conductive strips is four.

[0016] Further, the elastic member is a compression spring.

[0017] Further, a wire is provided between the lead body portion and the multimeter body.

[0018] Further, a threaded column is provided on the end of the fixed segment distal from the extension segment, and the threaded column is threadedly connected to the lead body portion.

[0019] Further, the elastic conductive strips are made of stainless steel.

[0020] Further, the lead body portion is provided with an anti-slip sleeve.

[0021] The beneficial effects of the present application are as follows:

[0022] The present application solves the safety hazard of traditional pen tip breakage by sleeving a rubber sleeve on the outer periphery of the telescopic section of the pen tip part, and fixing the two ends of the rubber sleeve on the pen tip head and the fixed section respectively. When the pen tip breaks, the rubber sleeve can wrap the broken pen tip residual section inside, avoiding the residual section from flying out to damage the detection target (such as a mutual inductor or other equipment) or causing personal injury to the detection personnel. Meanwhile, a plurality of elastic guide bars are arranged on the side wall of the rubber sleeve, and the rubber sleeve and the plurality of elastic guide bars greatly improve the bending strength of the pen tip part. When detecting a non-hole type target, even if the pen body is tilted and the pen tip is stressed, the elastic characteristics of the elastic guide bars can also allow the pen tip to automatically reset after the stress disappears, reducing the bending deformation after long-term use and prolonging the service life of the pen tip.

[0023] The present application sets a plurality of elastic guide bars in cooperation with the rubber sleeve. When the telescopic section is shortened, the elastic guide bars bend radially outward along the rubber sleeve and abut against the inner wall of the hole, and the contact area is significantly increased. Since the contact resistance is inversely proportional to the contact area, the contact resistance is greatly reduced, the interference with the polarity detection data is reduced, and the accuracy of the detection result is improved.

[0024] The present application sets a plurality of elastic guide bars, and the bending degree of the plurality of elastic guide bars is positively correlated with the hole diameter. The larger the hole diameter, the greater the compression amount of the telescopic section, and the more obvious the bending of the elastic guide bars, which can always tightly fit the inner wall of the hole. When the hole diameter is small, the bending degree of the elastic guide bars is low, and stable contact can still be maintained. Compared with the traditional fixed-size pen tip, the present device can adapt to holes of various diameters, avoiding the problem of loose contact caused by size mismatch.

[0025] The present application sets a rubber sleeve with a gradually thinning side wall from the fixed section to the pen tip head. When the pen tip head is inserted into the hole type target, only the part of the rubber sleeve inserted into the hole will expand and expose the elastic guide bars, and the elastic guide bars on the outside of the hole are still covered by the rubber sleeve, ensuring the required electrical conductivity for detection and reducing the probability of accidental contact with the exposed conductive components by the detection personnel. At the same time, the air in the hole is discharged when the rubber sleeve expands, reducing the risk of local arc.

[0026] The embodiments of the present application will be described in further detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present application.

[0028] Figure 2 It is a structural schematic diagram of the present application.

[0029] Figure 3 It is a structural view of the pen tip part of the present application.

[0030] Figure 4This is an exploded view of the pen tip portion of the present invention.

[0031] Figure 5 for Figure 3 Front view of the tip of the marker pen.

[0032] Figure 6 for Figure 5 A cross-sectional view of the tip of the marker pen along line AA.

[0033] Figure 7 for Figure 5 A cross-sectional view of the tip of the marker along BB.

[0034] Figure 8 This is a view showing the expanded state of the rubber sleeve on the tip of the pen in this invention.

[0035] Figure 9 for Figure 8 Front view of the expanded rubber sleeve of the pen tip.

[0036] Figure 10 for Figure 9 A cross-sectional view along CC of the rubber sleeve of the pen tip when it is inflated.

[0037] In the picture:

[0038] 100. Multimeter body; 110. Display screen; 120. Wires;

[0039] 200. Stamp; 210. Pen body; 211. Anti-slip sleeve; 220. Pen tip; 221. Threaded post; 230. Fixed section; 240. Telescopic section; 241. Guide rod; 242. Elastic element; 250. Pen tip; 260. Rubber sleeve; 270. Elastic guide strip; 280. Protrusion; 290. Sealed cavity. Detailed Implementation

[0040] See Figures 1-10A portable multi-channel polarity testing device, suitable for CT polarity testing, includes a multimeter body 100, a display screen 110 on the multimeter body 100 for displaying measurement data, and two probes 200 connected to the multimeter body 100 for connecting to the device under test. In the prior art, the probes 200 connect to the target device using their tips. Both probes 200 have a body portion 210 and a tip portion 220. The prior art probes 200 have various usage methods, including for non-perforated detection targets. In some testing methods, the pen body 210 is tilted so that the pen tip 220 is tilted and pressed against the device to be tested. However, this method may cause the pen tip 220 to bend or even break after prolonged use. In this case, the pen tip needs to be replaced, which affects the testing efficiency. If it breaks, the broken pen tip will fly out and damage the target being tested, and may even injure the testing personnel. When testing targets with holes, a cylindrical testing head is used. The size of this testing head is generally smaller than the diameter of the hole, which makes it unable to fit the hole well, increasing the contact resistance and affecting the testing results.

[0041] Based on this, the pen tip portion 220 of the pen 200 of the present invention includes a fixed section 230 and a telescopic section 240, such as Figure 3 As shown, the end of the telescopic section 240 furthest from the fixed section 230 is the pen tip 250. A rubber sleeve 260 is provided on the outer periphery of the telescopic section 240. One end of the rubber sleeve 260 is fixedly connected to the pen tip 250, and the other end of the rubber sleeve 260 is fixedly connected to the fixed section 230. When the pen tip 220 breaks off, the rubber sleeve 260 can retain the broken pen tip 220 inside the rubber sleeve 260, thereby preventing damage to the detection target or injury to the detection personnel when the pen tip 220 breaks off. Furthermore, multiple elastic guide strips 270 are provided on the side wall of the rubber sleeve 260. The elastic guide strips 270 are elastic and conductive, such as... Figure 4 , Figure 6 and Figure 7 As shown, multiple elastic guide strips 270 are parallel to the axis of the rubber sleeve 260, and are evenly distributed along the circumference of the rubber sleeve 260. The two ends of each elastic guide strip 270 are fixedly connected to the pen tip 250 and the fixed section 230, respectively, thus providing electrical conductivity. When the telescopic section 240 of the pen tip 220 is shortened, the multiple elastic guide strips 270 can bend outwards radially along the rubber sleeve 260. Figure 8 and Figure 10 As shown, the degree to which the multiple elastic guide strips 270 bend outward along the radial direction of the rubber sleeve 260 is positively correlated with the diameter of the hole.

[0042] When inspecting a perforated target, the inspector needs to insert the pen tip 250 into the hole and push the fixed section 230 to shorten the telescopic section 240, ensuring that the pen tip 250 can reach the bottom of the hole. When the diameter of the hole is larger, the telescopic section 240 of the pen tip needs to shorten by a greater distance, thereby increasing the degree to which the multiple elastic guide strips 270 bend radially outward along the rubber sleeve 260, and thus allowing the multiple elastic guide strips 270 to abut against the inner wall of the hole. When the diameter of the hole is smaller, the telescopic section 240 of the pen tip needs to shorten by a shorter distance, thereby reducing the degree to which the multiple elastic guide strips 270 bend radially outward along the rubber sleeve 260, thus adapting to smaller hole diameters and ensuring that the multiple elastic guide strips 270 can contact the inner wall of the hole.

[0043] Understandably, compared to only the tip 250 of the pen tip 220 contacting the bottom of the hole, the contact area between the probe 200 and the target is increased by multiple elastic guide strips 270 abutting against the sidewall of the hole. Since the contact resistance is inversely proportional to the size of the contact area, the contact resistance can be effectively reduced when the contact area between the probe 200 and the target is increased, thereby reducing the impact on the detection results and improving the accuracy of the detection results.

[0044] It should be noted that when the tester tilts the pen body 210 of the test pen 200 to test non-perforated targets, the rubber sleeve 260 and multiple elastic guide strips 270 of the pen tip 220 can improve the bending resistance of the pen tip 220. Compared with the pen tip 220 in the prior art that does not have elastic guide strips 270 and rubber sleeves 260, the pen tip 220 of the present invention has stronger bending resistance. In addition, the multiple elastic guide strips 270 are elastic. After the pen tip 220 has been used for a long time, the rubber sleeve 260 and multiple elastic guide strips 270 can restore the areas of the pen tip 220 that are prone to bending, reduce the degree of bending of the pen tip 220 after long-term use, and thus improve the service life of the pen tip 220 to a certain extent.

[0045] Specifically, in this embodiment of the invention, the telescopic section 240 of the pen tip portion 220 includes a guide rod 241 and an elastic element 242. The guide rod 241 is slidably inserted into the fixed section 230, which includes a sleeve. The guide rod 241 is slidably inserted into the sleeve. The elastic element 242 is located between the guide rod 241 and the sleeve of the fixed section 230. The elastic element 242 is a compression spring. Both ends of the elastic element 242 abut against the guide rod 241 and the sleeve, respectively. The elastic element 242 has a tendency to push the guide rod 241 out of the sleeve. The end of the guide rod 241 away from the elastic element 242 is fixedly connected to the pen tip 250. When the inspector inserts the pen tip 250 into the hole, he can push the fixed section 230, so that the guide rod 241 connected to the pen tip 250 moves axially within the sleeve of the fixed section 230 to compress the elastic element 242.

[0046] More specifically, in order to enable the multiple elastic guides 270 to bend outward along the radial direction of the rubber sleeve 260 when the telescopic section 240 of the pen tip 220 is shortened, a sealed cavity 290 is formed between the rubber sleeve 260 and the guide rod 241 in this embodiment. When the guide rod 241 slides axially within the sleeve of the fixed section 230 and shortens, the gas in the sealed cavity 290 is compressed, thereby pushing the rubber sleeve 260 outward to increase its diameter. Furthermore, the sidewall thickness of the rubber sleeve 260 gradually decreases from the sleeve of the fixed section 230 to the pen tip 250. As a result, when the gas inside the sealed cavity 290 is compressed, the rubber sleeve 260 with the thinner sidewall begins to expand outward first, thereby driving the multiple elastic guides 270 to bend outward along the radial direction of the rubber sleeve 260. As the distance of the telescopic section 240 shortens increases, the degree of outward expansion of the rubber sleeve 260 increases, and the expansion position of the rubber sleeve 260 gradually moves towards the position with the thicker sidewall.

[0047] It should be noted that, in this embodiment, a plurality of protrusions 280 are formed on the sidewall of the rubber sleeve 260 facing the axial direction of the rubber sleeve 260, such as... Figure 6 and Figure 7 As shown, multiple elastic guide strips 270 are located within multiple protrusions 280 facing the axial direction of the rubber sleeve 260. When the rubber sleeve 260 begins to expand, its diameter increases, thereby unfolding the protrusions 280. After the protrusions 280 are unfolded, the elastic guide strips 270 inside them are pushed and bent, and gradually exposed to the outer periphery of the rubber sleeve 260. This allows the elastic guide strips 270 to gradually approach the sidewall of the hole to ensure that the elastic guide strips 270 can abut against the sidewall of the hole.

[0048] Understandably, since the sidewall of the rubber sleeve 260 gradually expands from the thinner part to the thicker part, meaning the elastic guide strip 270 gradually protrudes from near the pen tip 250 to near the fixed section 230, and since the elastic guide strip 270 begins to protrude from near the pen tip 250, when the inspector inserts the pen tip 250 into the hole and pushes the fixed section 230, the pen tip 250 abuts against the bottom of the hole. At this time, the rubber sleeve 260 expands from near the pen tip 250 and pushes the elastic guide strip 270 at that position to bend and gradually contact the sidewall of the hole. If the diameter of the hole is small, the area of ​​expansion of the rubber sleeve 260 is small, and the elastic guide strip 270 is not exposed in the area where the rubber sleeve 260 is not expanded, thus providing protection and preventing safety problems caused by accidental contact by the inspector. At the same time, it can reduce the area of ​​the elastic guide strip 270 that comes into contact with the outside air and undergoes an oxidation reaction. The exposed part of the elastic guide strip 270 is located inside the hole. The air inside the hole is discharged from the hole under the expansion of the rubber sleeve 260. The elastic guide strip 270 located outside the hole is covered by the rubber sleeve 260, thereby reducing external corrosion.

[0049] In a further embodiment, the rubber sleeve 260 of the present invention has four protrusions 280 facing the axial direction, and the number of elastic guide strips 270 is four, with the four elastic guide strips 270 respectively located within the four protrusions 280. Of course, there can also be five, six, etc., which are not specifically limited here.

[0050] Specifically, in this embodiment, each of the two probes 200 has a wire 120 connected to its body 210. The other end of the wire 120 is connected to the multimeter body 100, so that current can flow through the probes 200 and the wire 120 through the multimeter body 100, and the display screen 110 on the multimeter body 100 displays the test result.

[0051] Specifically, to facilitate the connection between the pen body 210 and the pen tip 220 of the pen 200, a threaded post 221 is fixedly provided on the end of the fixed section 230 of the pen tip 220 away from the telescopic section 240. The outer circumference of the threaded post 221 is provided with threads, and the pen body 210 is provided with a threaded groove. The threaded post 221 is threaded into the threaded groove, thereby connecting the pen body 210 and the pen tip 220 together, making disassembly more convenient.

[0052] It should be noted that the threaded post 221 is made of conductive material, and it is electrically connected to the four elastic conductors 270 and the pen tip 250, thereby enabling current to be transmitted to the multimeter body 100. Meanwhile, the four elastic conductors 270 are made of stainless steel, which is both elastic and conductive, and also has strong oxidation resistance.

[0053] In a further embodiment, the pen body 210 of the present invention is provided with an anti-slip sleeve 211. The anti-slip sleeve 211 can increase the friction when the tester holds the pen body, and avoid the pen body slipping off due to sweaty hands, oil stains or sudden external force during operation.

[0054] The specific working process of the portable multi-channel polarity testing device provided by the present invention will be described in conjunction with the above embodiments:

[0055] When performing CT polarity testing, the multimeter body should be set to the DC milliamp or DC microamp range, and a smaller range, such as 10mA, should be selected for higher sensitivity.

[0056] When detecting perforated targets:

[0057] The two probes 200 of the multimeter body 100 are inserted into the test hole. The tester holds the body 210 of the probe 200 and inserts the tip 250 of the tip 220 into the hole. Then, the body 210 is moved, causing it to push the fixing section 230 of the tip 220. The fixing section 230 pushes the guide rod 241 to compress the elastic element 242, so that the tip 250 on the guide rod 241 can abut against the bottom of the hole, and part of the rubber sleeve 260 of the tip 220 also extends into the hole. As the tester continues to apply force, the elastic element 242 gradually... As the gas inside the sealed cavity 290 of the rubber sleeve 260 on the outer periphery of the guide rod 241 is compressed, the rubber sleeve 260 expands from the thinner part of its sidewall, that is, from the part of the rubber sleeve 260 near the tip 250. The diameter of the rubber sleeve 260 gradually increases, thus opening up the protrusion 280 formed on the sidewall facing the axis of the rubber sleeve 260. The elastic guide strip 270 inside the protrusion 280 gradually protrudes out of the outside of the rubber sleeve 260 and abuts against the inner sidewall of the hole, thereby increasing the contact area between the detection hole and the probe 200 and reducing the influence of contact resistance on the detection result.

[0058] When the diameter of the detection hole is large, the inspector continues to push the pen body 210, increasing the compression of the elastic element 242 by the guide rod 241 of the pen tip 220. At this time, the expansion diameter of the rubber sleeve 260 on the outer periphery of the guide rod 241 is larger, which makes the four elastic guide strips 270 on the side wall of the rubber sleeve 260 bend radially outward toward the rubber sleeve 260. This ensures that the four elastic guide strips 270 can abut against the inner side wall of the detection hole, while the rubber sleeve 260 that does not extend into the detection hole does not expand, thus protecting the part of the elastic guide strips 270 that does not extend into the detection hole, preventing this part from being exposed, and improving the safety of the detection process.

[0059] After the test is completed, the tester pulls the tip 220 of the two test probes 200 out of the hole. The telescopic section 240 of the tip 220 is reset under the action of the elastic element 242, which in turn drives the rubber sleeve 260 and the four elastic guide strips 270 to reset.

[0060] When detecting non-porous targets:

[0061] The tester tilted the two pen body parts 210 so that the pen tip part 220 tilted simultaneously. The pen tip 250 of the pen tip part 220 tilted to contact the non-perforated target, which can increase the contact area and reduce the contact resistance. At the same time, the rubber sleeve 260 on the outer periphery of the guide rod 241 and the four elastic guide strips 270 can provide the guide rod 241 and the pen tip 250 with a certain degree of bending resistance, thereby ensuring that the guide rod 241 and the pen tip part 220 are not easily bent during long-term use.

[0062] The above description is merely a specific embodiment of the present invention, and the various examples do not constitute a limitation on the substantive content of the present invention.

Claims

1. A portable multi-channel polarity testing device, characterized by, The utility model relates to a multimeter pen, including: A multimeter body (100) is provided with a display screen (110) on the multimeter body (100); Two table pens (200) are connected on the multimeter body (100), and the two table pens (200) are each provided with a pen body part (210) and a pen tip part (220), the pen tip part (220) includes a fixed section (230) and a telescopic section (240), the end of the telescopic section (240) away from the fixed section (230) is a pen tip head (250), a rubber sleeve (260) is sleeved on the outer periphery of the telescopic section (240), and the two ends of the rubber sleeve (260) are fixedly connected with the pen tip head (250) and the fixed section (230) respectively; A plurality of elastic guide bars (270) are electrically connected with the pen tip head (250) and the fixed section (230) respectively, the plurality of elastic guide bars (270) are parallel to the axis of the rubber sleeve (260), the plurality of elastic guide bars (270) are uniformly distributed on the side wall of the rubber sleeve (260) in the circumferential direction, the plurality of elastic guide bars (270) are elastic and can conduct electricity, the plurality of elastic guide bars (270) are configured to bend radially outward along the rubber sleeve (260) when the telescopic section (240) is shortened, and the degree of bending of the plurality of elastic guide bars (270) radially outward along the rubber sleeve (260) is positively correlated with the diameter of the hole. The telescopic section (240) includes a guide rod (241) and an elastic member (242), the guide rod (241) is slidingly inserted into the fixed section (230), and the elastic member (242) is located between the guide rod (241) and the fixed section (230); the elastic member (242) has a tendency to push the guide rod (241) to extend out of the fixed section (230); A sealed cavity (290) is formed between the guide rod (241) and the rubber sleeve (260), and the thickness of the rubber sleeve (260) gradually decreases from the fixed section (230) to the pen tip head (250); A plurality of protrusions (280) are formed on the side wall of the rubber sleeve (260) and face the axis direction of the rubber sleeve (260), and the plurality of elastic guide bars (270) are arranged in the plurality of protrusions (280) respectively, and the plurality of elastic guide bars (270) gradually extend out of the rubber sleeve (260) as the diameter of the rubber sleeve (260) increases.

2. The portable multi-channel polarity test device of claim 1, wherein, There are four protrusions (280) facing the axis direction of the rubber sleeve (260), and the number of elastic guide bars (270) is four.

3. The portable multi-channel polarity test device of claim 1, wherein, The elastic member (242) is a compression spring.

4. The portable multi-channel polarity test device of claim 1, wherein, A wire (120) is arranged between the pen body part (210) of the two table pens (200) and the multimeter body (100).

5. The portable multi-channel polarity test device of claim 1, wherein, A threaded column (221) is arranged on the end of the fixed section (230) of the table pen (200) away from the telescopic section (240), and the threaded column (221) is threadedly connected with the pen body part (210).

6. The portable multi-channel polarity test device of claim 1, wherein, The plurality of elastic guide bars (270) are made of stainless steel.

7. The portable multi-channel polarity test device of claim 1, wherein, The pen body part (210) of the table pen (200) is provided with an anti-skid sleeve (211).

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