Device for preventing inversion of flame detection fan

Abstract

The utility model relates to the technical field of fan inversion prevention, and discloses a flame detection fan inversion prevention device which comprises a centrifugal fan and a one-way control structure installed on one side of the centrifugal fan, a ratchet wheel is installed on the outer surface of a fan shaft, a clamping strip is inserted in the outer surface of the fan shaft, and the ratchet wheel is connected with the clamping strip. The outer side of the clamping strip is also inserted into the inner side of the limiting ring and the inner side of the ratchet wheel, mounting cylinders are mounted on the inner side of the protection box and located on one side of the mounting support B, and a stop block is movably mounted between the mounting cylinders. Under the condition that parts in the protection box are powered on, the stop block is separated from the ratchet wheel, the centrifugal fan can normally operate, and when the parts are not powered on, the stop block moves rightwards. The ratchet wheel is in contact with the ratchet wheel, the ratchet wheel can rotate in a meshed mode with the stop block when rotating clockwise, and the ratchet wheel cannot rotate in a meshed mode with the stop block due to the angle design when rotating anticlockwise, so that the centrifugal fan can only rotate in one direction.

Description

Technical Field

[0001] The utility model relates to the technical field of preventing the reverse rotation of a fan, in particular to a device for preventing the reverse rotation of a flame detection fan. Background Technique

[0002] The flame detection cooling fan is one of the important auxiliary equipment of the boiler unit set. It provides cooling air for the boiler flame detection. (The flame detector is one of the important components in the burner automatic device. It detects and monitors the flame in the furnace. When the boiler is ignited, operating at low load or in abnormal conditions, it can timely detect whether the furnace is extinguished. According to the detection results of the flame detection, the BMS (Burner Management System) performs relevant interlock actions to prevent furnace extinguishing and furnace explosion accidents). The working environment temperature of the flame detection probe is high and there is a lot of dust. The main function of the cooling air is to improve the working environment of the flame detection probe. The cooling air can properly cool down the probe and prevent its temperature from being too high. In addition, the blowing of the cooling air also plays a role in cleaning the probe. The flame detection cooling fan plays a crucial role in the reliable operation of the thermal power plant boiler.

[0003] During the normal operation of the boiler, it is not allowed to stop two cooling fans at the same time, otherwise it may burn out the flame detector. For safety and to save the power consumption of the fan at low load, usually two fans are set up and arranged in parallel. When the boiler load is low, one fan operates and the other fan is in standby. Since the outlets of the fans are connected and the outlet of the operating fan is at positive pressure, the flue gas or air may enter the inlet of the standby fan from the outlet of the operating fan through the outlet of the standby fan. The flue gas or air flows reversely through the impeller, resulting in the reverse rotation of the standby fan. When the boiler load is high, both fans operate, and the reverse rotation of the fan poses a great safety hazard to the startup of the fan. In severe cases, it may cause motor overload, fan shaft breakage, etc., leading to equipment failures and affecting the safe and reliable operation of the unit.

[0004] Therefore, we propose a device for preventing the reverse rotation of the flame detection fan to solve the problems mentioned above. Content of the Utility Model

[0005] The purpose of the utility model is to provide a device for preventing the reverse rotation of the flame detection fan to solve the problem that the flue gas or air flows reversely through the impeller, resulting in the reverse rotation of the standby fan as mentioned in the above background technique.

[0006] To achieve the above purpose, the utility model provides the following technical solution: A device for preventing the reverse rotation of a flame detection fan includes a centrifugal fan and a one-way control structure installed on one side of the centrifugal fan. The one-way control structure includes a ratchet sleeve installed on the outer surface of the fan shaft in the centrifugal fan, and a protective member is installed on the outside of the ratchet sleeve and at the upper end of the centrifugal fan.

[0007] The ratchet sleeve includes protective boxes fixedly installed on both sides of the outer surface of the fan shaft. A ratchet is installed on the outer surface of the fan shaft between the two groups of protective boxes. A clamping strip is inserted on the outer surface of the fan shaft, and the outer side of the clamping strip is also inserted inside the limit ring and the ratchet.

[0008] The protective component includes a protective box and a mounting bracket A installed at the inner side end of the protective box. An electromagnet is installed on one side of the mounting bracket A. An electric control switch is installed on the outer surface of the protective box. And a mounting bracket B is installed on the inner wall of the protective box on the side of the electromagnet. An armature is movably installed at the top of the mounting bracket B. An installation cylinder is installed on the inner side of the protective box on the side of the mounting bracket B. A stop block is movably installed between the installation cylinders.

[0009] Preferably, stop rotating shafts are installed on both sides of the lower end of the stop block. The stop rotating shafts are movably installed inside the installation cylinder. A spring is installed on the outer surface of the armature.

[0010] Preferably, a torsion spring is wound around the outer surface of the stop rotating shaft. One end of the torsion spring is installed at the lower end of the stop block, and the other end of the torsion spring is installed on the inner wall of the installation cylinder.

[0011] Preferably, a rotating hole is penetrated and opened at the upper end of the protective box, and the rotating hole is matched with the limit ring.

[0012] Preferably, a bent slot is opened on the inner wall of the opening side of the protective box. A bent sliding plate is movably installed at the opening of the bent slot and the protective box. The side of the bent sliding plate away from the bent slot is outside the protective box. An inner built-in strip is installed between the insides of the bent sliding plate and is outside the protective box. A handle is installed on one side of the inner built-in strip.

[0013] Preferably, a threaded hole B is penetrated and opened on the side of the bent sliding plate close to the bent slot. A threaded hole A is penetrated and opened on the outer surface of the protective box on the opening side. A bolt is threadedly connected inside the threaded hole A and the threaded hole B.

[0014] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0015] (1) For the reverse rotation prevention device of the flame detector fan of the present utility model, when the components inside the protective box are electrified, the stop block is separated from the ratchet, and the centrifugal fan can operate normally. When it cannot be electrified, the stop block moves to the right and contacts the ratchet. When the ratchet rotates clockwise, it can mesh and rotate with the stop block. When rotating counterclockwise, due to the angle design, the ratchet and the stop block cannot mesh and rotate, so that the centrifugal fan can only rotate in one direction.

[0016] (2)The anti-reverse device for the flame detector fan provided by the present utility model enables the centrifugal fan to have a locking function against reverse rotation through the provided one-way control structure, so that the centrifugal fan can avoid a series of problems such as motor overload and fan shaft breakage caused by the reverse rotation of the fan, eliminate the equipment hidden dangers existing due to the reverse rotation of the fan, improve the equipment reliability, and is of great significance for the safe and economic operation ability of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic diagram of the overall structure of the present utility model;

[0018] Figure 2 is a schematic diagram of the ratchet sleeve structure of the present utility model;

[0019] Figure 3 is a schematic diagram of the protective member structure of the present utility model;

[0020] Figure 4 is a schematic diagram of the internal structure of the protective box of the present utility model;

[0021] Figure 5 For the present utility model Figure 4 is an enlarged view of part A in.

[0022] In the figure: 1, centrifugal fan; 2, one-way control structure; 21, ratchet sleeve; 211, limit ring; 212, ratchet; 213, clamping strip; 22, protective member; 221, protective box; 2211, mounting bracket A; 2212, electromagnet; 2213, mounting bracket B; 2214, armature; 2215, spring; 2216, stop block; 2217, stop rotating shaft; 2218, mounting cylinder; 2219, torsion spring; 222, bent slide plate; 223, built-in strip; 224, handle; 225, bent slot; 226, threaded hole A; 227, threaded hole B; 228, rotating hole; 229, electric control switch; 23, bolt. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0024] Embodiment 1: Please refer to Figures 1-5, Fire detection fan reverse prevention device, including a centrifugal fan 1 and a one-way control structure 2 installed on one side of the centrifugal fan 1. The one-way control structure 2 includes a ratchet sleeve 21 installed on the outer surface of the fan shaft in the centrifugal fan 1, and a protective member 22 is installed on the outer side of the ratchet sleeve 21 and at the upper end of the centrifugal fan 1.

[0025] The ratchet sleeve 21 includes protective boxes 221 fixedly installed on both sides of the outer surface of the fan shaft. A ratchet 212 is installed on the outer surface of the fan shaft between the two groups of protective boxes 221. A clamping strip 213 is inserted on the outer surface of the fan shaft, and the outer side of the clamping strip 213 is also inserted inside the limit ring 211 and the ratchet 212.

[0026] The protective member 22 includes a protective box 221 and a mounting bracket A2211 installed at the inner side end of the protective box 221. An electromagnet 2212 is installed on one side of the mounting bracket A2211. An electric control switch 229 is installed on the outer surface of the protective box 221. A mounting bracket B2213 is installed on the inner wall of the protective box 221 and on one side of the electromagnet 2212. An armature 2214 is movably installed at the top of the mounting bracket B2213. The armature 2214 is in the shape of a capital "I", and the middle position of the armature 2214 is hinged to both the stop block 2216 and two iron bars close to the electromagnet 2212. An installation cylinder 2218 is installed on the inner side of the protective box 221 and on one side of the mounting bracket B2213. A stop block 2216 is movably installed between the installation cylinders 2218. The top of the stop block 2216 meshes with the ratchet 212 to control the rotation direction of the ratchet 212 and the centrifugal fan 1 in a single direction.

[0027] Both sides of the lower end of the stop block 2216 are installed with stop rotating shafts 2217. The stop rotating shafts 2217 are movably installed inside the installation cylinder 2218. A spring 2215 is installed on the outer surface of the armature 2214. The installation cylinder 2218 restricts the positions of the stop block 2216 and the stop rotating shafts 2217.

[0028] A torsion spring 2219 is wound around the outer surface of the stop rotating shaft 2217. One end of the torsion spring 2219 is installed at the lower end of the stop block 2216, and the other end of the torsion spring 2219 is installed on the inner wall of the installation cylinder 2218. When the electromagnet 2212 is not powered on, the stop block 2216 can rely on the return force of the torsion spring 2219 to mesh its top in the ratchet 212, facilitating the one-way rotation of the ratchet 212 and the centrifugal fan 1.

[0029] In this embodiment: When the centrifugal fan 1 is operating normally, the stop block 2216 is disengaged from the ratchet wheel 212 installed on the shaft of the centrifugal fan 1. By energizing the electromagnet 2212, the electromagnet 2212 attracts one end of the armature 2214 to approach. The armature 2214 changes, and the other end of the armature 2214 is used to attract the stop block 2216 to move leftward and be fixed at the zero position without contact, which does not affect the normal operation of the centrifugal fan 1. The spring 2215 provided increases the attraction force of the armature 2214 on the stop block 2216. The electric control switch 229 can be designed in forms such as near operation, remote operation, and fan interlock. After the centrifugal fan 1 stops operating, the electric control switch 229 is turned off. When the centrifugal fan 1 is operating, the electromagnet 2212 is de-energized. Under the action of the spring 2215, the stop block 2216 moves rightward and contacts the ratchet wheel 212. When the ratchet wheel 212 rotates clockwise, it can mesh and rotate with the stop block 2216. When rotating counterclockwise, due to the angle design, the ratchet wheel 212 cannot mesh and rotate with the stop block 2216. Thus, the centrifugal fan 1 can only rotate in one direction, realizing the function of preventing the fire detection cooling centrifugal fan 1 from rotating in reverse. When the centrifugal fan 1 needs to be started, the function of preventing the centrifugal fan 1 from rotating in reverse needs to be released first. It can be designed as an automatic interlock, that is, the one-way control structure 2 is released first and then the centrifugal fan 1 is started. When the centrifugal fan 1 is operating normally, even if it fails due to various reasons, under the action of the torsion spring 2219, the stop block 2216 moves rightward and contacts the ratchet wheel 212, only generating slight friction and making abnormal noises, without causing the centrifugal fan 1 to rotate and be damaged.

[0030] Embodiment Two: Please refer to Figure 3 , a rotating hole 228 is penetrated and opened at the upper end of the protective box 221, and the rotating hole 228 matches the limiting ring 211, facilitating the rotation of the ratchet sleeve 21 inside the protective box 221.

[0031] On the inner wall of one side of the opening of the protective box 221, a bent slot 225 is opened. A bent sliding plate 222 is movably installed at the opening of the bent slot 225 and the protective box 221. The side of the bent sliding plate 222 away from the bent slot 225 is outside the protective box 221. An inner strip 223 is installed between the interiors of the bent sliding plates 222 and outside the protective box 221. A handle 224 is installed on one side of the inner strip 223. The handle 224 can be held by hand, facilitating pulling the bent sliding plate 222 to move and maintaining the parts inside the protective box 221.

[0032] On one side of the bent slide plate 222 and close to the bent slot 225, a threaded hole B227 is drilled through. On the outer surface of the protective box 221 and on one side of the opening, a threaded hole A226 is drilled through. A bolt 23 is threadedly connected inside the threaded hole A226 and the threaded hole B227. The bolt 23 is used to fix between the bent slide plate 222 and the protective box 221, facilitating the use of the protective box 221 and the bent slide plate 222 to protect the parts inside the protective box 221.

[0033] In this embodiment: Rotate the bolt 23, and hold the handle 224 to pull out one side of the bent slide plate 222 from the inside of the bent slot 225, and the inside of the protective box 221 is opened, facilitating the operator to regularly check the components used inside the protective box 221. Moreover, the provided protective box 221 will reduce the propagation range of the noise generated by the contact between the stopper 2216 and the ratchet wheel 212.

[0034] Working principle: When the components inside the protective box 221 are electrified, the stopper 2216 is separated from the ratchet wheel 212, and the centrifugal fan 1 can operate normally. When it cannot be electrified, the stopper 2216 moves to the right and contacts the ratchet wheel 212. When the ratchet wheel 212 rotates clockwise, it can engage and rotate with the stopper 2216. When rotating counterclockwise, due to the angle design, the ratchet wheel 212 cannot engage and rotate with the stopper 2216, so that the centrifugal fan 1 can only rotate unidirectionally.

[0035] The content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

[0036] Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A device for preventing a fire detection fan from reversing, comprising a centrifugal fan (1) and a one-way control structure (2) installed on one side of the centrifugal fan (1), characterized in that: The one-way control structure (2) comprises a ratchet sleeve (21) mounted on the outer surface of a fan shaft in the centrifugal fan (1), and a protective component (22) is mounted on the outer side of the ratchet sleeve (21) and at the upper end of the centrifugal fan (1); The ratchet sleeve (21) comprises a protective box (221) fixedly mounted on both sides of the outer surface of the fan shaft, a ratchet (212) is mounted between two sets of the protective boxes (221) and on the outer surface of the fan shaft, a retaining strip (213) is inserted on the outer surface of the outer surface of the fan shaft, and the outer side of the retaining strip (213) is also inserted on the inner side of the limiting ring (211) and the ratchet (212); The protective component (22) comprises a protective box (221) and a mounting bracket A (2211) mounted on the inner side end of the protective box (221), an electromagnet (2212) being mounted on one side of the mounting bracket A (2211), an electric control switch (229) being mounted on the outer surface of the protective box (221), a mounting bracket B (2213) being mounted on the inner wall of the protective box (221) and on one side of the electromagnet (2212), an armature (2214) being movably mounted on the top of the mounting bracket B (2213), a mounting cylinder (2218) being mounted on the inner side of the protective box (221) and on one side of the mounting bracket B (2213), and a stopper (2216) being movably mounted between the mounting cylinders (2218).

2. The device for preventing the fire detection fan from reversing according to claim 1 is characterized in that: Stop shafts (2217) are installed on both sides of the lower end of the stop block (2216). The stop shafts (2217) are movably installed inside the installation cylinder (2218). A spring (2215) is installed on the outer surface of the armature (2214).

3. The device for preventing the fire detection fan from reversing according to claim 2 is characterized in that: A torsion spring (2219) is wound around the outer surface of the stop shaft (2217), one end of the torsion spring (2219) is mounted on the lower end of the stop block (2216), and the other end of the torsion spring (2219) is mounted on the inner wall of the mounting cylinder (2218).

4. The device for preventing the fire detection fan from reversing according to claim 1 is characterized in that: A rotating hole (228) is formed through the upper end of the protection box (221), and the rotating hole (228) matches the limiting ring (211).

5. The device for preventing the fire detection fan from reversing according to claim 4 is characterized in that: A curved slot (225) is provided on the inner wall of one side of the opening of the protection box (221); a curved slide plate (222) is movably installed between the curved slot (225) and the opening of the protection box (221); a side of the curved slide plate (222) away from the curved slot (225) is located outside the protection box (221); an internal strip (223) is installed between the inside of the curved slide plate (222) and outside the protection box (221); and a handle (224) is installed on one side of the internal strip (223).

6. The device for preventing the fire detection fan from reversing according to claim 5, characterized in that: A threaded hole B (227) is formed through the curved slide plate (222) on one side close to the curved slot (225), and a threaded hole A (226) is formed through the outer surface of the protective box (221) on one side of the opening. Bolts (23) are connected to the internal threads of the threaded hole A (226) and the threaded hole B (227).

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