Dust alarm sensor

Abstract

The utility model belongs to the field of metal dust treatment, and relates to a dust alarm sensor, which comprises a probe and at least one binding post group arranged at one end of the probe, and each binding post group comprises two binding posts capable of being connected with an external power supply; the probe is provided with a conductive coating which can form an electric loop with the two binding posts. The dust alarm sensor provided by the utility model is low in cost and convenient to maintain.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of dust treatment, and relates to an alarm sensor, in particular to a dust alarm sensor. BACKGROUND

[0002] In a system of pneumatic conveying powder, a filter device is often needed to ensure that dust is not discharged into the atmosphere or sucked into a fan, and the filter device is generally a filter core. During use, if the filter core is damaged, dust will be discharged into the atmosphere or sucked into a power device such as a fan. This can seriously cause the operator to inhale dust or damage the fan, and even cause dust explosion. Therefore, an effective dust detection means is needed to prevent the above-mentioned situation. Conventional dust detection is generally based on the light scattering principle, and this method needs laser and corresponding light sensors, so the price is high. SUMMARY

[0003] In order to solve the above technical problems in the background art, the utility model provides a dust alarm sensor which is low in cost and convenient to maintain.

[0004] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme:

[0005] A dust alarm sensor, characterized in that: the dust alarm sensor comprises a probe and at least one group of terminal posts arranged at one end of the probe, each group of terminal posts comprises two terminal posts which can be connected with an external power supply; and a conductive coating capable of forming an electric circuit with the two terminal posts is arranged on the probe.

[0006] The conductive coating is arranged on the probe in an axial direction of the probe, or the conductive coating is arranged on the probe in a direction parallel to the axial direction of the probe, or the conductive coating is arranged on the probe in a direction perpendicular to the axial direction of the probe.

[0007] The conductive coating is a linear coating or a planar coating.

[0008] The conductive coating is a carbon-based coating, and the carbon-based coating is a graphene coating, a carbon nanotube coating or a graphite coating.

[0009] The probe comprises an insulator and a connecting lug arranged at an end of the insulator; the insulator is connected with the terminal posts through the connecting lug; the conductive coating is arranged on the side of the insulator; and the number of the connecting lugs matches the number of the terminal posts.

[0010] The insulator has a columnar structure as a whole.

[0011] The insulator is a cylinder or a prism.

[0012] The dust alarm sensor further comprises a connecting screw arranged on the connecting lug, and the probe is connected with the connecting post through the connecting screw; and the connecting screw forms an electric circuit through a conductive coating.

[0013] The dust alarm sensor further comprises a terminal box, an outer metal pin is arranged on the terminal box, and an electric circuit board connected with the metal pin is arranged in the terminal box; an outer thread is arranged on the outer periphery of the connecting post, and an inner thread is arranged on the axial direction of the connecting post; the connecting screw is connected with the connecting post through the inner thread; and the connecting post is connected with the electric circuit board through the outer thread.

[0014] The dust alarm sensor is arranged in a system for pneumatic conveying of powder and at a position where powder should not appear under normal conditions, and in particular, the conductive coating on the dust alarm sensor is arranged at a position which can be impacted by powder under abnormal conditions.

[0015] The dust alarm sensor has the advantages that:

[0016] The dust alarm sensor comprises a probe and at least one group of connecting posts arranged at one end of the probe, each group of connecting posts comprises two connecting posts which can be connected with an external power supply, and a conductive coating is arranged on the probe and can form an electric circuit with the two connecting posts. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a schematic diagram of the overall structure of the dust alarm sensor provided by the utility model;

[0018] Figure 2 is a schematic diagram of the cross-sectional structure of the dust alarm sensor provided by the utility model;

[0019] Among them:

[0020] 1-probe; 2-connecting screw; 3-connecting post; 4-terminal box; 5-conductive coating. DETAILED DESCRIPTION

[0021] Referring to Figure 1 and Figure 2The utility model provides a kind of dust alarm sensor, including probe 1 and at least one group of terminal post group being set in the one end of probe 1, each terminal post group includes two terminal posts 3 that can be connected with external power supply;Probe 1 is provided with the electrically conductive coating 5 that can form electric circuit with two terminal posts 3.The dust alarm sensor provided by the utility model is when working, is placed in the system of pneumatic conveying powder and in normal circumstances should not appear the position of powder, especially the electrically conductive coating 5 on dust alarm sensor is placed in the position that can be impacted by powder under abnormal condition, exemplary, probe 1 with electrically conductive coating 5 can be directly placed in the pipeline or filter core to be detected, two terminal posts 3 are placed in the outside of pipeline or filter core, since probe 1 is insulator, so no electric circuit is formed between two terminal posts 3, no current passes in loop.When electrically conductive coating is set on probe 1, due to the effect of electrically conductive coating 5, electric circuit is formed between two terminal posts 3 by electrically conductive coating 5, when, then current passes in loop when terminal post is connected to external power supply.When there is powder in pipeline or filter core, especially hard powder such as metal particles, powder will continuously impact, collide or scratch the electrically conductive coating 5 on the surface of probe 1, with the continuous effect of powder, electrically conductive coating 5 gradually separates from probe 1 or is scratched, and the flow capacity of electric circuit will gradually decrease, until disconnected.The change will be reflected on external ammeter or ohmmeter, and current suddenly drops or resistance continuously or suddenly rises, and the amount of drop or rise exceeds threshold value, then it indicates that there is dust in pipeline.The current, that is, through the change of ammeter or ohmmeter, the flow condition of dust in pipeline or filter core can be directly obtained or monitored, and good early warning or alarm function is played.Therefore, the application scenario of the utility model is the occasion that needs to monitor dust and has enough air volume (such as not enough air volume, fan can also be added, and sufficient air volume is artificially manufactured), and dust has certain hardness and density (for example, metal powder).

[0022] The conductive coating 5 is a linear coating, a strip coating or a surface coating arranged on the probe 1, regardless of the shape of the conductive coating 5, as long as an electric loop can be formed between the two connecting posts 3. The linear coating has a smaller contact area with dust, and is easily detached from the probe 1 when impacted, collided or scratched by dust, so that the electric loop between the two connecting posts 3 is easily damaged, thereby improving the sensitivity of the utility model. The strip coating has a larger contact area with dust than the linear coating, although the sensitivity is lost, but the service life of the dust alarm sensor provided by the utility model can be prolonged. Of course, in other embodiments, a surface coating with a larger contact area can also be used. For example, the conductive coating 5 is a linear coating or a surface coating arranged in the axial direction of the probe 1, when the probe 1 is inserted into the pipeline or filter element to be detected (the axial direction of the probe 1 is perpendicular to the dust flow direction), the dust flowing through the probe 1 has a larger contact probability with the conductive coating 5 on the probe, thereby further improving the detection sensitivity. Of course, the conductive coating 5 is a linear coating or a surface coating perpendicular to the axial direction of the probe 1, at this time, when the probe 1 is inserted into the pipeline or filter element to be detected (the axial direction of the probe 1 is parallel to the dust flow direction), the dust flowing through the probe 1 has a larger contact probability with the conductive coating 5 on the probe, thereby further improving the detection sensitivity. In addition, the conductive coating 5 can be arranged on the probe 1 in a direction parallel to the axial direction of the probe 1, for example, a diagonal arrangement, V-shaped arrangement and the like can be used, as long as an electric loop is formed between the two connecting posts 3, which will not be repeated here.

[0023] The conductive coating 5 used in the utility model can be a material commonly used or used in the prior art which has a conductive ability, generally a carbon-based coating, such as a graphene coating, a carbon nanotube coating and a graphite coating and the like, which has excellent conductive performance and mechanical properties. For example, in the embodiment, the material of the conductive coating 5 is preferably graphite, which has excellent conductive performance and is easy to wear, so as to ensure that the device has higher sensitivity. The conductive coating 5 does not need to coat the entire probe 1, but only needs to ensure that an electric loop is formed between the two connecting posts 3.

[0024] Referring to Figure 2 The probe 1 used in the utility model comprises an insulator and a connecting lug arranged at the end of the insulator; the insulator is connected with the connecting post 3 through the connecting lug; the conductive coating 5 is arranged on the peripheral side of the insulator; and the number of the connecting lug matches the number of the connecting post 3. The insulator has a columnar structure as a whole, for example, the insulator is a cylinder or a prism or other three-dimensional structure, preferably, a prism, especially a three-prism. In the prism, due to the existence of the prism, the conductive coating 5 can form a linear structure on the peripheral side of the probe 1, that is, a linear coating, which can provide the maximum projection area perpendicular to the pipeline cross section under the condition of the minimum pressure drop, so that more powder is scraped over the surface of the probe when the pipeline filter element is broken.

[0025] The dust alarm sensor also includes a connecting screw 2 disposed on the connecting lug, which connects the probe 1 to the terminal 3 via the connecting screw 2. The connecting screw 2 forms an electrical circuit through the conductive coating 5. The connecting screw 2 connects the probe 1 to the terminal 3. The connecting screw 2 is preferably a brass countersunk screw, which provides a larger indirect contact area between the connecting screw 2 and the probe 1 and has excellent conductivity.

[0026] The dust alarm sensor also includes a junction box 4, which has metal pins on its exterior and a circuit board connected to them inside. Terminals 3 are threaded externally and internally, with screws 2 connected to them via internal threads. Terminals 3 are connected to the circuit board via external threads. Terminals 3 are brass-made, while junction box 4, an insulating material, provides a protective housing for the device. Inside, the junction box contains related electronic components (such as resistors). Two metal pins extend from the top of the junction box 4, connecting to an external power source and an ammeter (or resistance meter).

[0027] by Figure 2 Taking the dust alarm sensor shown as an example, the working method of the present invention is as follows: first, the probe 1 is coated with a graphite coating as required (the less coating, the more sensitive the reaction, but the shorter the service life and the greater the risk of false triggering, and vice versa), and the device is connected to the pipeline to be monitored through threads, flanges, etc., ensuring that the probe is exposed to the air path of the pipeline, and the pins of the junction box 4 are connected to the external power supply and ammeter, and the current is continuously monitored. During operation, if the filter element is damaged, powder will continue to impact, collide or scratch the probe 1. When the coating is scraped off, the flow capacity of the electrical circuit will gradually decrease until it is disconnected. This process will cause the ammeter reading to decrease (or the resistance meter reading to increase), which will trigger the device alarm; when the coating is excessively worn, it is only necessary to remove the probe 1, remove the connecting screw 2, and re-spray the graphite coating.

Claims

1. A dust alarm sensor, characterized by: The dust alarm sensor comprises a probe (1) and at least one terminal group arranged at one end of the probe (1), each terminal group comprising two terminals (3) that can be connected to an external power supply; and a conductive coating (5) that can form an electrical circuit with the two terminals (3) is provided on the probe (1).

2. The dust alarm sensor according to claim 1, characterized in that: The conductive coating (5) is arranged on the probe (1) along the axial direction of the probe (1); or, the conductive coating (5) is arranged on the probe (1) along a direction parallel to the axial direction of the probe (1); or, the conductive coating (5) is arranged on the probe (1) along a direction perpendicular to the axial direction of the probe (1).

3. The dust alarm sensor according to claim 2, characterized in that: The conductive coating (5) is a linear coating or a surface coating.

4. The dust alarm sensor according to claim 1, 2 or 3, characterized in that: The conductive coating (5) is a carbon-based coating, and the carbon-based coating is a graphene coating, a carbon nanotube coating or a graphite coating.

5. The dust alarm sensor according to claim 4, characterized in that: The probe (1) comprises an insulator and a connecting ear arranged at the end of the insulator; the insulator is connected to the terminal post (3) via the connecting ear; the conductive coating (5) is arranged on the circumference of the insulator; the number of the connecting ears matches the number of the terminal posts (3).

6. The dust alarm sensor according to claim 5, characterized in that: The insulator has a columnar structure as a whole.

7. The dust alarm sensor according to claim 6, characterized in that: The insulator is a cylinder or a prism.

8. The dust alarm sensor according to claim 7, characterized in that: The dust alarm sensor further comprises a connecting screw (2) arranged on the connecting ear, and the probe (1) is connected to the terminal (3) via the connecting screw (2); the connecting screw (2) forms an electrical circuit via the conductive coating (5).

9. The dust alarm sensor according to claim 8, characterized in that: The dust alarm sensor further comprises a junction box (4), the outside of the junction box (4) is provided with a metal pin, and the inside of the junction box (4) is provided with a circuit board connected to the metal pin; the outer periphery of the terminal post (3) is provided with an external thread, and the axial direction of the terminal post (3) is provided with an internal thread; the connecting screw (2) is connected to the terminal post (3) via the internal thread; and the terminal post (3) is connected to the circuit board via the external thread.

10. The dust alarm sensor according to claim 9, characterized in that: The dust alarm sensor is placed in a system for pneumatically conveying powder and in a position where powder should not appear under normal circumstances. The conductive coating (5) on the dust alarm sensor is placed in a position where it can be impacted by powder under abnormal circumstances.

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