A foreign object protection device for server racks
By using an electric friction guard device in the air-cooled equipment of power equipment, the problem of filter clogging in air-cooled equipment is solved by utilizing the high-voltage circuit to carbonize foreign objects and drive the metal mesh to self-clean through friction, thereby improving heat dissipation efficiency and equipment stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- RUNYANG ENERGY TECH CO LTD
- Filing Date
- 2022-10-20
- Publication Date
- 2026-05-26
AI Technical Summary
In existing technologies, the filters of air-cooled power equipment are easily clogged by foreign objects such as mosquitoes, flying catkins, and dust, resulting in reduced heat dissipation efficiency and potentially causing overheating and damage to the equipment in severe cases.
An electric friction guard device is used to form a high-voltage circuit between the positive and negative metal mesh when foreign objects enter. The foreign objects are carbonized and generate electric sparks, which start the generator to drive the metal mesh to self-clean through friction. The fan reverses and blows the foreign objects off to prevent them from entering the cabinet.
It eliminates the need for manual cleaning, improves the efficiency and timeliness of foreign object removal, maintains stable cabinet operation and heat dissipation, and prevents foreign object blockage.
Smart Images
Figure CN115764570B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power system technology, and in particular to a foreign object protection device for a server rack. Background Technology
[0002] In power systems, some electrical equipment generates high temperatures during operation. To ensure stable operation of these devices, air-cooling equipment is typically used to cool them down.
[0003] In practice, electrical equipment is often installed outdoors. Insects, fluff, dust, and other foreign matter can adhere to the filter surface of air-cooled equipment, clogging the filter and reducing heat dissipation efficiency. Currently, high-pressure air guns and water guns are commonly used to clean the filter screens to prevent clogging.
[0004] However, after being washed by wind or water, the internal structure of the filter cotton in the filter will be damaged, making the filter unable to filter foreign objects. At this time, due to the use of air-cooling equipment, the air flow rate is accelerated, which will cause foreign objects to be adsorbed on the filter surface at a faster speed. A large number of foreign objects accumulate on the filter surface, further reducing the heat dissipation efficiency of the air-cooling equipment. In severe cases, it may cause the electrical equipment to overheat and be damaged. Summary of the Invention
[0005] In view of this, the purpose of this application is to provide a foreign object prevention device for a server rack. When a foreign object enters the gap between the positive and negative metal meshes of the electric friction guard, a high-voltage circuit is formed, carbonizing foreign objects such as lint and insects that come into contact with the metal mesh and generating an electric spark. Under the action of the electric spark, the generator is started, and the generator drives the positive and negative metal meshes to rotate at different speeds. Due to the speed difference, the metal meshes rub against each other to achieve self-cleaning of the guard. The auxiliary circuit of the motor is linked to the fan inside the server rack to reverse, blowing off the carbonized foreign objects attached to the surface of the electric friction guard, preventing lint, insects and other foreign objects from entering the server rack.
[0006] In a first aspect, embodiments of this application provide an anti-foreign object device for a server rack, wherein a fan for heat dissipation is installed inside the server rack, and the anti-foreign object device includes an electric friction guard and a guard friction drive circuit, wherein the electric friction guard is installed at the air inlet of the server rack and includes an annular positive metal mesh and a negative metal mesh, an active mechanism and a driven mechanism, and the guard friction drive circuit includes an optocoupler, a common relay and a motor;
[0007] The positive and negative metal meshes are used to connect to high voltage direct current when the power switch is closed. When foreign objects enter the gap between the positive and negative metal meshes, a high voltage circuit is formed, and the foreign objects that come into contact with the electric friction guard are carbonized and generate electric sparks under the action of high voltage direct current.
[0008] The optocoupler is used to energize the coil of the ordinary relay when an electric spark is generated, thereby switching the contacts of the ordinary relay from a normally open state to a normally closed state and starting the motor.
[0009] The electric motor is used to drive the active mechanism to rotate. The active mechanism simultaneously drives the outer positive metal mesh and the inner negative metal mesh to rotate around the active mechanism and the driven mechanism. Through the speed difference between the positive metal mesh and the negative metal mesh, the positive metal mesh and the negative metal mesh rub against each other to achieve self-cleaning of the mesh.
[0010] The auxiliary circuit of the electric motor is also used to drive the fan to reverse so that the fan blows away foreign objects attached to the surface of the electric friction guard.
[0011] In one possible implementation, the guardrail friction drive circuit further includes a time-delay relay, the contacts of which are connected to the motor.
[0012] The time-delay relay is used to control its contacts to switch from a normally open state to a normally closed state after a preset time interval, thereby starting the motor.
[0013] In one possible implementation, the foreign object protection device further includes a step-down rectifier circuit, a flyback step-up transformer, and a DC step-up circuit connected in sequence.
[0014] The step-down rectifier circuit is used to reduce the voltage level of 220V AC power through half-bridge rectification to obtain a safe voltage.
[0015] The flyback step-up transformer is used to step up the safety voltage once.
[0016] The DC boost circuit is used to boost the safety voltage a second time, generating a high-voltage DC current between the two plates to power the positive and negative metal meshes. The two plates are connected in parallel with a current-limiting resistor.
[0017] In one possible implementation, the primary side of the flyback step-up transformer has a first winding, a second winding, and a third winding, wherein the first winding and the second winding serve as the main power circuit, and the second winding and the third winding serve as the sampling voltage circuit.
[0018] In one possible implementation, the DC boost circuit includes a full-bridge rectifier circuit and a voltage storage medium consisting of multiple capacitors connected in series.
[0019] In one possible implementation, the foreign object prevention device further includes a louver structure and filter cotton;
[0020] The louver structure is installed on the outside of the electric friction guard net to protect the electric friction guard net;
[0021] The filter cotton is installed on the inside of the electric friction guard to filter foreign objects entering from the air inlet.
[0022] In one possible implementation, the active mechanism and the driven mechanism have the same external dimensions, are both made of high-strength engineering ABS material, and are both composed of transmission gears and bearings.
[0023] In one possible implementation, both the positive electrode metal mesh and the negative electrode metal mesh are flexible metal meshes.
[0024] This application provides an anti-foreign object device for server racks. When a foreign object enters the gap between the positive and negative metal meshes of the electric friction guard, a high-voltage circuit is formed, carbonizing foreign objects such as lint and insects that come into contact with the metal mesh and generating an electric spark. Under the action of the electric spark, a generator is started, which drives the positive and negative metal meshes to rotate at different speeds. The metal meshes rub against each other due to the speed difference, achieving self-cleaning of the guard. The auxiliary circuit of the motor is linked to the fan inside the server rack to reverse, blowing off the carbonized foreign objects attached to the surface of the electric friction guard, preventing lint, insects and other foreign objects from entering the server rack.
[0025] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 A schematic diagram of a foreign object prevention device for a server rack provided in an embodiment of this application is shown.
[0028] Figure 2 This illustration shows a structural schematic diagram of an electric friction guard provided in an embodiment of this application;
[0029] Figure 3 This illustration shows a schematic diagram of airflow in a cabinet according to an embodiment of this application;
[0030] Figure 4 A schematic diagram of a protective mesh friction drive circuit provided in an embodiment of this application is shown;
[0031] Figure 5 An electrical schematic diagram of a high-voltage direct current provided in an embodiment of this application is shown;
[0032] Figure 6 A schematic diagram of a protective netting structure provided in an embodiment of this application is shown. Detailed Implementation
[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0034] At present, in the power system, some electrical equipment generates high temperatures when working. In order to ensure the stable operation of the electrical equipment, air-cooling equipment is usually used to cool down these electrical equipment.
[0035] In practice, electrical equipment is often installed outdoors. Insects, fluff, dust, and other foreign matter can adhere to the filter surface of air-cooled equipment, clogging the filter and reducing heat dissipation efficiency. Currently, high-pressure air guns and water guns are commonly used to clean the filter screens to prevent clogging.
[0036] However, after being washed by wind or water, the internal structure of the filter cotton in the filter will be damaged, making the filter unable to filter foreign objects. At this time, due to the use of air-cooling equipment, the air flow rate is accelerated, which will cause foreign objects to be adsorbed on the filter surface at a faster speed. A large number of foreign objects accumulate on the filter surface, further reducing the heat dissipation efficiency of the air-cooling equipment. In severe cases, it may cause the electrical equipment to overheat and be damaged.
[0037] Based on the above problems, this application provides a foreign object prevention device for server racks. When a foreign object enters the gap between the positive and negative metal meshes of the electric friction guard, a high-voltage circuit is formed, carbonizing foreign objects such as lint and insects that come into contact with the metal mesh and generating an electric spark. Under the action of the electric spark, the generator is started, and the generator drives the positive and negative metal meshes to rotate at different speeds. Due to the speed difference, the metal meshes rub against each other, achieving self-cleaning of the guard. The auxiliary circuit of the motor is linked to the fan inside the server rack to reverse, blowing off the carbonized foreign objects attached to the surface of the electric friction guard, preventing lint, insects and other foreign objects from entering the server rack.
[0038] The shortcomings of the above solutions are the result of the inventor's practical experience and careful research. Therefore, the discovery process of the above problems and the solutions proposed in this application below should be considered as the inventor's contributions to this application.
[0039] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. The components of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0040] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0041] See Figure 1 As shown, Figure 1 This is a schematic diagram of a foreign object prevention device for a server rack provided in an embodiment of this application. The server rack is equipped with a fan for heat dissipation. The foreign object prevention device includes an electric friction guard 101 and a guard friction drive circuit 102. The electric friction guard 101 is installed at the air inlet of the server rack and includes an annular positive metal mesh and a negative metal mesh, an active mechanism, and a driven mechanism. The guard friction drive circuit 102 includes an optocoupler, a common relay, and a motor.
[0042] The positive and negative metal meshes are used to connect to high-voltage direct current when the power switch is closed. When a foreign object enters the gap between the positive and negative metal meshes, a high-voltage circuit is formed, and the foreign object in contact with the electric friction guard is carbonized and generates an electric spark under the action of high-voltage direct current.
[0043] The optocoupler is used to energize the coil of the ordinary relay when an electric spark is generated, thereby switching the contacts of the ordinary relay from a normally open state to a normally closed state and starting the motor.
[0044] The electric motor is used to drive the active mechanism to rotate. The active mechanism simultaneously drives the outer positive metal mesh and the inner negative metal mesh to rotate around the active mechanism and the driven mechanism. Through the speed difference between the positive metal mesh and the negative metal mesh, the positive metal mesh and the negative metal mesh rub against each other to achieve self-cleaning of the mesh.
[0045] The auxiliary circuit of the electric motor is also used to drive the fan to reverse so that the fan blows away foreign objects attached to the surface of the electric friction guard.
[0046] In this embodiment, a fan is installed inside the rack. The fan can rotate forward or reverse under the drive of a motor; forward rotation is used for heat dissipation. The rack has air inlets and outlets. The electric friction guard is the same size as the air inlet, allowing for seamless installation at the rack's air inlet. See also... Figure 2 As shown, Figure 2 This is a schematic diagram of the structure of an electric friction guard provided in an embodiment of this application, wherein 2.1 is the active mechanism, 2.2 is the positive electrode metal mesh, 2.3 is the negative electrode metal mesh, and 2.4 is the driven mechanism. Figure 2 The left side of the middle section shows a schematic diagram of the overall structure of the active mechanism. Figure 2 The right side of the diagram shows a cross-sectional view of the electric friction guard net. The driven mechanism and the driving mechanism are parallel in position and identical in size. Driven by the driving mechanism, the positive and negative metal meshes rotate around the driving and driven mechanisms at different speeds. The positive metal mesh is located on the outer side (away from the driving and driven mechanisms), and the negative metal mesh is located on the inner side (close to the driving and driven mechanisms). When the positive and negative metal meshes rotate around the driving and driven mechanisms, it is similar to two layers of superimposed tracks rotating around a rolling device, with the positive metal mesh on the outer layer and the negative metal mesh on the inner layer. Due to the speed difference, the positive and negative metal meshes rub against each other, enabling the guard net to self-clean.
[0047] Optionally, both the driving and driven mechanisms consist of transmission gears and bearings, and are made of high-strength engineering ABS material with good insulation properties. Both the positive and negative metal meshes are flexible to ensure that the electric friction guards are not easily damaged when rotating around the driving and driven mechanisms. The difference is that the driving mechanism is internally connected to the motor via transmission gears and bearings, while the driven mechanism only contains transmission gears and bearings.
[0048] When the power switch is closed, the positive and negative metal meshes are connected to the positive and negative terminals of the high-voltage direct current, respectively. When a foreign object enters the gap between the positive and negative metal meshes, a high-voltage circuit is formed. At this time, the foreign object that comes into contact with the electric friction guard will be carbonized by the high-voltage direct current, generating an electric spark. The foreign object includes insects, flying fluff, dust, and any other object that may come into contact with and block the electric friction guard.
[0049] In the friction drive circuit of the protective mesh, the optocoupler is connected in series with the coil of a common relay, and the contacts of the common relay are connected in series with the motor. The contacts of the common relay are normally open. When no foreign object enters the gap between the positive and negative metal meshes, no electric spark is generated on the electric friction protective mesh. At this time, the contacts of the common relay are in the normally open state, and the motor does not start. When a foreign object enters the gap between the positive and negative metal meshes, an electric spark is generated on the electric friction protective mesh. At this time, the coil of the common relay connected in series with the optocoupler is energized, and the contacts of the common relay change from the normally open state. When the system switches to the normally closed state, the motor starts and drives the active mechanism in the electric friction guard to rotate. The active mechanism simultaneously drives the outer positive metal mesh and the inner negative metal mesh to rotate at different speeds. Due to the speed difference, the positive and negative metal meshes rub against each other, making it easier for carbonized foreign objects attached to the surface of the metal mesh to fall off, thus achieving self-cleaning of the guard. There is no need for manual cleaning of foreign objects, which can reduce the use of manpower, improve the efficiency and timeliness of foreign object cleaning, effectively prevent the guard from being blocked, keep the air intake unobstructed, continuously dissipate heat from the cabinet, and ensure the stable and safe operation of the cabinet.
[0050] In addition, the electric motor's auxiliary circuit can also drive the fan to rotate. See also Figure 3 As shown, Figure 3 This application provides a schematic diagram of airflow direction in a server rack, as shown in the embodiments of the present application. Figure 3 In the diagram, 3.1 is the air inlet of the cabinet, and 3.2 is the air outlet. The fan is installed on the side of the air inlet. When the fan rotates forward, it accelerates the airflow in the vicinity, causing air to flow from the air inlet side to the air outlet side. It should be noted that the motor driving the fan to rotate forward for heat dissipation (the first motor) is different from the motor in the friction drive circuit of the protective mesh (the second motor). When no foreign objects enter the gap between the positive and negative metal meshes, the first motor drives the fan to rotate forward to dissipate heat from the cabinet. When foreign objects enter the gap between the positive and negative metal meshes, the auxiliary circuit of the second motor drives the fan to rotate in reverse. The fan blows away the carbonized foreign objects attached to the surface of the electric friction protective mesh, preventing the carbonized foreign objects from clogging the electric friction protective mesh.
[0051] The foreign object prevention device for server racks provided in this application embodiment connects the electric friction guard to a high-voltage direct current, causing foreign objects that come into contact with the guard to carbonize. Based on the electric sparks generated during the carbonization of the foreign objects, the motor in the guard friction drive circuit is started. The motor drives the active mechanism in the guard to rotate, thereby causing the positive and negative metal meshes to rotate at different speeds. Due to the speed difference, the metal meshes rub against each other, enabling the guard to self-clean. In addition, the auxiliary circuit of the motor can drive the fan to reverse and blow away foreign objects attached to the surface of the electric friction guard, improving the efficiency and timeliness of foreign object removal.
[0052] Furthermore, the protective mesh friction drive circuit also includes a time delay relay, the contacts of which are connected to the motor; the time delay relay is used to control its contacts to switch from a normally open state to a normally closed state after a preset time interval, thereby starting the motor.
[0053] See Figure 4 As shown, Figure 4 This is a schematic diagram of a guardrail friction drive circuit provided in an embodiment of this application. Figure 4 In the diagram, B1 is an optocoupler, K2 is a general-purpose relay, K3 is a time-delay relay, M1 is a motor, and FAN is the fan inside the cabinet. Motor M1 has two starting devices: one is the optocoupler and general-purpose relay, used to start motor M1 when a foreign object comes into contact with the electric friction guard and generates an electric spark; the other is the time-delay relay, used to start motor M1 periodically after a preset time interval to clean the electric friction guard.
[0054] Figure 4 In the process, optocoupler B1 has three interfaces. Interface 1 and interface 2 are connected to 24V and 0V respectively to provide power to the optocoupler. Interface 3 is connected to a regular relay. Figure 4 The lower half of the device is the fan drive circuit inside the cabinet. The L and N terminals are connected to 220V AC power. U1 is the electrical circuit related to the forward and reverse function of the FAN. Correspondingly, U1 is the auxiliary circuit of the motor in the guardrail friction drive circuit to realize the switching of different states of different fans.
[0055] Furthermore, the electric friction guard in this embodiment needs to be connected to a high-voltage direct current power supply, see [link to relevant documentation]. Figure 5 As shown, Figure 5 An electrical schematic diagram of a high-voltage direct current circuit is provided for an embodiment of this application. Figure 5 The foreign object prevention device also includes a step-down rectifier circuit, a flyback step-up transformer T1, and a DC step-up circuit connected in sequence.
[0056] The step-down rectifier circuit is used to reduce the voltage level of 220V AC power through half-bridge rectification to obtain a safe voltage.
[0057] The flyback step-up transformer T1 is used to step up the safety voltage once.
[0058] The DC boost circuit is used to boost the safety voltage a second time, generating a high voltage DC current between the two plates P1 and P2 to power the positive and negative metal meshes. The two plates P1 and P2 are connected in parallel with a current-limiting resistor R1.
[0059] Specifically, F1 serves as the main switch for the electrical circuit providing high-voltage DC power. Optionally, F1 can be a push button; pressing F1 starts the power supply for the entire electrical circuit. The L and N terminals of the step-down rectifier circuit are connected to 220V AC power. The voltage is reduced to a safe voltage through a half-bridge rectifier. The voltage is then boosted once by the flyback step-up transformer T1 and then boosted a second time by the DC step-up circuit. A voltage difference is generated between the output terminals P1 and P2 to provide high-voltage DC power. R1 serves as current limiting protection, conducting short-circuit current in the event of an internal short circuit to protect the safety of other components in the electrical circuit.
[0060] Furthermore, Figure 5 In the above, the primary side of the flyback step-up transformer has a first winding 1, a second winding 2, and a third winding 3. The first winding 1 and the second winding 2 serve as the main power circuit, while the second winding 2 and the third winding 3 serve as the sampling voltage circuit.
[0061] Furthermore, Figure 5 In this circuit, the DC boost circuit includes a full-bridge rectifier circuit and a voltage storage medium consisting of multiple capacitors connected in series. After the initial boost, the safe voltage is rectified by the full-bridge rectifier circuit and then connected to a multi-electrode capacitor for charging, thus achieving further voltage boosting through the series connection of the capacitors.
[0062] Furthermore, the foreign object prevention device also includes a louver structure and filter cotton; a louver structure is added to the outside of the electric friction guard, and filter cotton is added to the inside of the electric friction guard. See also Figure 6 As shown, Figure 6 This is a schematic diagram of a protective net structure provided in an embodiment of this application. Figure 6 In this design, 1 represents a louvered structure, 2 represents an electric friction guard, and 3 represents filter cotton. The louvered structure 1 is installed on the outside of the electric friction guard 2 to protect it; the filter cotton 3 is installed on the inside of the electric friction guard 2 to filter foreign objects entering from the air inlet.
[0063] This application provides an anti-foreign object device for server racks, designed to prevent filters in power cooling systems from being clogged by dust, insects, and other foreign objects, thus ensuring effective heat dissipation, reducing maintenance costs, and eliminating the need for manual cleaning. The device consists of multiple parts, including an electrical circuit, a protective mesh, and a friction drive circuit for the protective mesh. The protective mesh comprises a louvered structure, an electric friction mesh, and filter cotton. The positive and negative metal meshes of the electric friction mesh are connected to a high-voltage direct current circuit. When foreign objects enter the gap between the positive and negative metal meshes, a high-voltage circuit is formed, carbonizing any flying lint, insects, or other foreign objects that come into contact with the metal mesh, and then... Figure 4 The protective mesh friction drive circuit shown uses motor M1 to cause the positive and negative metal meshes to rub against each other due to the speed difference. Simultaneously, it activates fan FAN to reverse and blow air, expelling foreign objects from the cabinet. This device, through high voltage, metal mesh friction, and fan reversal, prevents lint, insects, and other foreign objects from entering the cabinet. The airflow direction within the cabinet is as follows: Figure 3 As shown, the air outlet at 3.2 is always under negative pressure, preventing foreign objects such as mosquitoes and flying catkins from entering. Therefore, it is sufficient to install a protective screen only at the air inlet. The size of the protective screen can be flexibly adjusted to match the size of the air inlet. The protective screen of this device can be adapted to various application scenarios.
[0064] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The scope of protection of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A foreign object prevention device for server racks, characterized in that, The cabinet is equipped with a fan for heat dissipation. The foreign object protection device includes an electric friction guard and a guard friction drive circuit. The electric friction guard is installed at the air inlet of the cabinet and includes an annular positive metal mesh and a negative metal mesh, an active mechanism and a driven mechanism. The guard friction drive circuit includes an optocoupler, a common relay and a motor. The positive and negative metal meshes are used to connect to high voltage direct current when the power switch is closed. When foreign objects enter the gap between the positive and negative metal meshes, a high voltage circuit is formed, and the foreign objects that come into contact with the electric friction guard are carbonized and generate electric sparks under the action of high voltage direct current. The optocoupler is used to energize the coil of the ordinary relay when an electric spark is generated, thereby switching the contacts of the ordinary relay from a normally open state to a normally closed state and starting the motor. The electric motor is used to drive the active mechanism to rotate. The active mechanism simultaneously drives the outer positive metal mesh and the inner negative metal mesh to rotate around the active mechanism and the driven mechanism. Through the speed difference between the positive metal mesh and the negative metal mesh, the positive metal mesh and the negative metal mesh rub against each other to achieve self-cleaning of the mesh. The auxiliary circuit of the electric motor is also used to drive the fan to reverse so that the fan blows away foreign objects attached to the surface of the electric friction guard.
2. The anti-foreign object device for server racks according to claim 1, characterized in that, The protective mesh friction drive circuit also includes a time delay relay, the contacts of which are connected to the motor; The time-delay relay is used to control its contacts to switch from a normally open state to a normally closed state after a preset time interval, thereby starting the motor.
3. The anti-foreign object device for server racks according to claim 1, characterized in that, The foreign object protection device also includes a step-down rectifier circuit, a flyback step-up transformer, and a DC step-up circuit connected in sequence. The step-down rectifier circuit is used to reduce the voltage level of 220V AC power through half-bridge rectification to obtain a safe voltage. The flyback step-up transformer is used to step up the safety voltage once. The DC boost circuit is used to boost the safety voltage a second time, generating a high-voltage DC current between the two plates to power the positive and negative metal meshes. The two plates are connected in parallel with a current-limiting resistor.
4. The anti-foreign object device for server racks according to claim 3, characterized in that, The primary side of the flyback step-up transformer has a first winding, a second winding, and a third winding. The first winding and the second winding serve as the main power circuit, while the second winding and the third winding serve as the sampling voltage circuit.
5. The anti-foreign object device for server racks according to claim 3, characterized in that, The DC boost circuit includes a full-bridge rectifier circuit and a voltage storage medium consisting of multiple capacitors connected in series.
6. The anti-foreign object device for server racks according to claim 1, characterized in that, The foreign object prevention device also includes a louver structure and filter cotton; The louver structure is installed on the outside of the electric friction guard net to protect the electric friction guard net; The filter cotton is installed on the inside of the electric friction guard to filter foreign objects entering from the air inlet.
7. The anti-foreign object device for server racks according to claim 1, characterized in that, The active mechanism and the driven mechanism have the same external dimensions, are both made of high-strength engineering ABS material, and are both composed of transmission gears and bearings.
8. The anti-foreign object device for server racks according to claim 1, characterized in that, Both the positive electrode metal mesh and the negative electrode metal mesh are flexible metal meshes.