Air duct electric heater

Abstract

The utility model relates to the technical field of electric heaters, in particular to an air duct electric heater which comprises a heat insulation sleeve, the top of the heat insulation sleeve is connected with a filter pipe, the top of the inner wall of the filter pipe is connected with a filter screen, and dust in air flow blown in through pressurization is intercepted and filtered through the filter screen arranged on the filter pipe. Air flow enters the filter pipe and then flows into two positions, one position flows into the heat insulation sleeve to facilitate follow-up heating, the other position flows into the vent hole and flows into the piston cylinder through the air blowing pipe, and the piston cylinder can gradually stretch out to extrude the spring along with the more inflow air, so that when air flow conveying is stopped, the air flow is stopped from flowing into the air blowing pipe. When the filter screen is cleaned, the spring rebounds to extrude gas in the piston cylinder to be exhausted, and airflow flowing backwards from inside to outside is formed, so that dust intercepted by the filter screen is conveniently blown away through the reverse airflow, the attached dust is prevented from influencing air circulation, the frequency of cleaning the filter screen is reduced, and the maintenance cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of electric heaters, in particular to an air duct electric heater. Background Technique

[0002] The air duct type electric heater is mainly used for heating the air in the air duct. Through the air supply system, the gas entering the air duct type electric heater forms high-temperature and high-pressure gas and is discharged. The generated hot air is dry, moisture-free, static-free, non-conductive, non-combustible, non-explosive, non-electrochemically corrosive, pollution-free, safe and reliable, and is widely applied to aspects such as aerospace, ordnance industry, chemical industry, heating of the gasifying air of the air conveying chute in power stations, and heating of the gasifying air in ash silos.

[0003] The prior art such as the published number CN215216706U provides an air duct type electric heater convenient for dust prevention, including an electric heater box body. One side of the electric heater box body is provided with an air inlet pipe, and the other side of the electric heater box body is provided with an air outlet pipe. The inner wall of the air inlet pipe is fixedly connected with a fixing ring, and a double-layer dust-proof net is arranged inside the fixing ring. One side of the double-layer dust-proof net is attached to the inner wall of the fixing ring, and the other side of the double-layer dust-proof net is attached with an annular pressing plate. By means of the double-layer dust-proof net in the utility model, dust in the air is blocked from entering the equipment interior, so as to avoid affecting the air heating efficiency and preventing loss of the high-temperature resistance wire inside the equipment. After the double-layer dust-proof net is used for a long time, by rotating the knob to move the round plate away from the annular pressing plate, the annular pressing plate no longer presses the double-layer dust-proof net, and the double-layer dust-proof net is taken out from inside the fixing ring, which is convenient for cleaning or replacing the double-layer dust-proof net.

[0004] In this solution, the air duct type electric heater uses a dust-proof net to prevent dust from entering the equipment interior, so as to avoid affecting the air heating efficiency and preventing loss of the high-temperature resistance wire inside the equipment. However, the above dust-proof component is inconvenient to replace when replacing, and it needs to be replaced regularly, which is rather troublesome. In view of this, we propose an air duct electric heater. Content of the Utility Model

[0005] The purpose of the utility model is to provide an air duct electric heater, which solves the problem that the dust-proof component is rather troublesome to clean.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] An air duct electric heater includes a heat insulation sleeve. A filter pipe is connected to the top of the heat insulation sleeve. A filter screen is connected to the top of the inner wall of the filter pipe. An air vent ring is connected to the bottom of the filter pipe. Air vent holes are connected to the inner wall of the air vent ring. An air blowing pipe is connected to the outer wall of the air vent ring and is communicated with the air vent holes. A piston rod is connected to the bottom of the air blowing pipe. The piston rod is slidably connected to the inner wall of a piston cylinder, and the piston cylinder is communicated with the air blowing pipe through a through hole formed in the inner wall of the piston rod. A support ring is sleeved on the top of the outer wall of the piston cylinder. A support block is arranged below the piston cylinder and is connected to the heat insulation sleeve. A spring is connected between the support block and the support ring. By providing the filter screen on the filter pipe to intercept and filter the dust in the pressurized blown air flow, it is avoided that the dust enters the heat insulation sleeve and affects heating. After the air flow enters the filter pipe, it flows to two places respectively. One place flows into the heat insulation sleeve for subsequent heating, and the other place flows into the air vent holes and flows into the interior of the piston cylinder through the air blowing pipe. As more gas flows in, the piston cylinder will gradually extend and compress the spring. When the air flow is stopped, the spring will rebound and squeeze the gas in the piston cylinder to be discharged, forming an air flow that pours from the inside to the outside, so as to conveniently blow off the dust intercepted by the filter screen through the reverse air flow, avoid the attached dust affecting the air circulation, reduce the frequency of cleaning the filter screen, and reduce the maintenance cost.

[0008] Preferably, the number of the air blowing pipes is six groups. The spring surrounds the outside of the piston cylinder. The shape of the filter screen is hemispherical, which has a larger filtering area and avoids affecting the air circulation.

[0009] Preferably, a ring-shaped impeller is arranged at a position above the air vent ring inside the filter pipe, and the ring-shaped impeller is rotatably connected to the filter pipe. The gas discharged from the piston cylinder blows the ring-shaped impeller to conveniently form an air flow that pours from the inside to the outside to blow off the dust.

[0010] Preferably, an air inlet pipe is connected to the top of the filter pipe, and a hair dryer is connected to the top of the air inlet pipe. By starting the hair dryer to blow air into the air inlet pipe, since the inner diameter of the air inlet pipe is larger than that of the filter pipe, the air is pressurized and blown in.

[0011] Preferably, an air outlet is connected to the bottom of the heat insulation sleeve, and an air inlet is connected to the top of the heat insulation sleeve, and the inner diameter of the air inlet is smaller than the inner diameter of the heat insulation sleeve. Since the inner diameter of the air inlet is smaller than the inner diameter of the heat insulation sleeve, the air flow rate will slow down at this time to facilitate heating.

[0012] Preferably, a metal sleeve is connected to the inner wall of the heat insulation sleeve, and an electric heating tube is connected to the bottom of the inner wall of the heat insulation sleeve. The shape of the electric heating tube is spiral. By setting the electric heating tube in a spiral shape to increase the contact area with the air, and combining with the heat absorption efficiency of the material of the metal sleeve itself, when the electric heating tube is heated, the metal sleeve will also quickly absorb heat. Through the way that the air flow contacts two heat sources, namely the electric heating tube and the metal sleeve, the heat transfer efficiency is improved.

[0013] Preferably, the intake pipe, the filter pipe and the heat insulation sleeve are on the same axis, and the inner diameter of the ventilation hole is larger than the inner diameter of the blowing pipe.

[0014] With the above technical solutions, the present utility model provides an air duct electric heater, which has at least the following beneficial effects:

[0015] First, the present utility model intercepts and filters the dust in the pressurized blown air flow through the filter net on the filter pipe to prevent the dust from entering the heat insulation sleeve and affecting the heating. After the air flow enters the filter pipe, it flows to two places respectively. One place flows into the heat insulation sleeve for subsequent heating, and the other place flows into the ventilation hole and flows into the inside of the piston cylinder through the blowing pipe. As more gas flows in, the piston cylinder will gradually extend, squeezing the spring. When the air flow delivery stops, the spring will rebound, squeezing the gas in the piston cylinder to be discharged, forming an in-to-out backflow air flow to facilitate blowing off the dust intercepted by the filter net by the reverse air flow, preventing the attached dust from affecting the air circulation, reducing the frequency of cleaning the filter net, and thus reducing the maintenance cost.

[0016] Second, the present utility model sets the electric heating tube in a spiral shape to increase the contact area with the air, and combines with the heat absorption efficiency of the material of the metal sleeve itself. When the electric heating tube is heated, the metal sleeve will also quickly absorb heat. Through the way that the air flow contacts two heat sources, namely the electric heating tube and the metal sleeve, the heat transfer efficiency is improved. Description of the Drawings

[0017] The drawings described herein are used to provide a further understanding of the present utility model and form a part of this application:

[0018] Figure 1 It is a schematic diagram of the overall structure of the present utility model;

[0019] Figure 2 It is a partial cross-sectional view of the filter pipe in the present utility model;

[0020] Figure 3 It is a partial cross-sectional view of the blowing pipe in the present utility model;

[0021] Figure 4 It is a partial cross-sectional view of the heat insulation sleeve in the present utility model.

[0022] In the figure: 1, heat insulation sleeve; 10, air inlet; 11, metal sleeve; 12, electric heating tube; 13, air outlet; 2, filter tube; 21, filter net; 22, ventilation ring; 23, ventilation hole; 24, blowing tube; 241, piston rod; 242, piston cylinder; 243, support ring; 244, support block; 245, spring; 25, annular impeller; 3, air inlet pipe; 4, hair dryer. Specific implementation mode

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

[0024] An air duct electric heater, such as Figures 1-4As shown in the figure, it includes a heat insulation sleeve 1. The top of the heat insulation sleeve 1 is connected to a filter pipe 2. The top of the inner wall of the filter pipe 2 is connected to a filter net 21. The bottom of the filter pipe 2 is connected to a ventilation ring 22. The inner wall of the ventilation ring 22 is connected to ventilation holes 23. The outer wall of the ventilation ring 22 is connected to a blowing pipe 24, and the blowing pipe 24 is communicated with the ventilation holes 23. The bottom of the blowing pipe 24 is connected to a piston rod 241. The outer wall of the piston rod 241 is slidably connected to a piston cylinder 242, and the piston cylinder 242 is communicated with the blowing pipe 24 through a through hole opened in the inner wall of the piston rod 241. A support ring 243 is sleeved on the top of the outer wall of the piston cylinder 242. A support block 244 is arranged below the piston cylinder 242, and the support block 244 is connected to the heat insulation sleeve 1. A spring 245 is connected between the support block 244 and the support ring 243. By arranging the filter net 21 on the filter pipe 2 to intercept and filter the dust in the pressurized and blown air flow, it is avoided that the dust enters the heat insulation sleeve 1 and affects heating. After the air flow enters the filter pipe 2, it flows to two places respectively. One place flows into the heat insulation sleeve 1 to facilitate subsequent heating. The other place flows into the ventilation holes 23 and flows into the inside of the piston cylinder 242 through the blowing pipe 24. As more gas flows in, at this time the piston cylinder 242 will gradually extend, squeezing the spring 245. When the air flow is stopped, the spring 245 will rebound, squeezing the gas in the piston cylinder 242 to be discharged, forming an air flow that pours back from the inside to the outside, so as to facilitate blowing off the dust intercepted by the filter net 21 through the reverse air flow, avoiding the attached dust from affecting the air circulation, reducing the frequency of cleaning the filter net 21, and reducing the maintenance cost. The number of the blowing pipes 24 is six groups. The spring 245 surrounds the outside of the piston cylinder 242. The shape of the filter net 21 is hemispherical, which has a larger filtering area and avoids affecting the air circulation. A ring-shaped impeller 25 is arranged at the position above the ventilation ring 22 inside the filter pipe 2, and the ring-shaped impeller 25 is rotatably connected to the filter pipe 2. The gas discharged from the piston cylinder 242 is used to blow the ring-shaped impeller 25 to facilitate forming an air flow that pours back to blow off the dust. The top of the filter pipe 2 is connected to an air inlet pipe 3. The top of the air inlet pipe 3 is connected to a hair dryer 4. By starting the hair dryer 4 to blow air into the air inlet pipe 3, since the inner diameter of the air inlet pipe 3 is larger than that of the filter pipe 2, the air is pressurized and blown in.

[0025] In this embodiment, by starting the hair dryer 4 to blow air into the intake pipe 3, since the inner diameter of the intake pipe 3 is larger than that of the filter pipe 2, the air is pressurized and blown in. The dust in the pressurized air flow is intercepted and filtered by the filter screen 21 provided on the filter pipe 2 to prevent the dust from entering the heat insulation sleeve 1 and affecting the heating. After the air flow enters the filter pipe 2, it flows to two places respectively. One place flows into the heat insulation sleeve 1 for subsequent heating, and the other place flows into the vent hole 23 and flows into the inside of the piston cylinder 242 through the blow pipe 24. As more gas flows in, the piston cylinder 242 will gradually extend, squeezing the spring 245. When the air flow is stopped, the spring 245 will rebound, squeezing the gas in the piston cylinder 242 out. The gas discharged from the piston cylinder 242 blows the annular impeller 25 to form an air flow flowing backward from the inside to the outside, so as to conveniently blow away the dust intercepted by the filter screen 21 by the reverse air flow, prevent the attached dust from affecting the air circulation, reduce the frequency of cleaning the filter screen 21, and reduce the maintenance cost. Embodiment

[0026] As Figure 4 shown, an air outlet 13 is connected to the bottom of the heat insulation sleeve 1, and an air inlet 10 is connected to the top of the heat insulation sleeve 1. The inner diameter of the air inlet 10 is smaller than the inner diameter of the heat insulation sleeve 1. Since the inner diameter of the air inlet 10 is smaller than the inner diameter of the heat insulation sleeve 1, the air flow rate will slow down at this time to facilitate heating. A metal sleeve 11 is connected to the inner wall of the heat insulation sleeve 1, and an electric heating tube 12 is connected to the position at the bottom of the inner wall of the heat insulation sleeve 1. The shape of the electric heating tube 12 is spiral. By setting the electric heating tube 12 in a spiral shape to increase the contact area with the air, and cooperating with the heat absorption efficiency of the material of the metal sleeve 11 itself, when the electric heating tube 12 is heated, the metal sleeve 11 will also quickly absorb heat. Through the way that the air flow passes through two heat sources, namely the electric heating tube 12 and the metal sleeve 11, the heat transfer efficiency is improved. The intake pipe 3, the filter pipe 2 and the heat insulation sleeve 1 are on the same axis, and the inner diameter of the vent hole 23 is larger than the inner diameter of the blow pipe 24.

[0027] In this embodiment, when the gas enters the heat insulation sleeve 1, since the inner diameter of the air inlet 10 is smaller than the inner diameter of the heat insulation sleeve 1, the air flow rate will slow down at this time to facilitate heating. By setting the electric heating tube 12 in a spiral shape to increase the contact area with the air, and cooperating with the heat absorption efficiency of the material of the metal sleeve 11 itself, when the electric heating tube 12 is heated, the metal sleeve 11 will also quickly absorb heat. Through the way that the air flow passes through two heat sources, namely the electric heating tube 12 and the metal sleeve 11, the heat transfer efficiency is improved.

[0028] When a duct electric heater of the present utility model is in use, the blower 4 is started to blow air into the intake pipe 3. Since the inner diameter of the intake pipe 3 is larger than that of the filter pipe 2, the air is pressurized and blown in. The dust in the pressurized airflow is intercepted and filtered by the filter screen 21 provided on the filter pipe 2 to prevent dust from entering the heat insulation sleeve 1 and affecting heating. After the airflow enters the filter pipe 2, it flows to two places respectively. One place flows into the heat insulation sleeve 1 for subsequent heating, and the other place flows into the vent hole 23 and flows into the interior of the piston cylinder 242 through the blow pipe 24. As more gas flows in, the piston cylinder 242 will gradually extend, squeezing the spring 245. When the air supply stops, the spring 245 will rebound, squeezing the gas in the piston cylinder 242 to be discharged. The gas discharged from the piston cylinder 242 blows the annular impeller 25 to form an airflow flowing backward from the inside to the outside, so as to conveniently blow away the dust intercepted by the filter screen 21 by the reverse airflow, prevent the attached dust from affecting the air circulation, and reduce the frequency of cleaning the filter screen 21. When the gas enters the heat insulation sleeve 1, since the inner diameter of the air inlet 10 is smaller than that of the heat insulation sleeve 1, the air flow rate will slow down for convenient heating. By arranging the electric heating pipe 12 in a spiral shape to increase the contact area with the air, and cooperating with the heat absorption efficiency of the material of the metal sleeve 11 itself, when the electric heating pipe 12 is heated, the metal sleeve 11 will also quickly absorb heat. Through the way that the air flow passes through two heat sources, namely the electric heating pipe 12 and the metal sleeve 11, the heat transfer efficiency is improved.

[0029] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device.

[0030] Although the embodiments of the present utility model have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. An air duct electric heater, comprising a heat insulation sleeve (1), characterized in that: The top of the heat insulation sleeve (1) is connected with a filter pipe (2). The top of the inner wall of the filter pipe (2) is connected with a filter net (21). The bottom of the filter pipe (2) is connected with an air vent ring (22). The inner wall of the air vent ring (22) is connected with air vent holes (23). The outer wall of the air vent ring (22) is connected with a blowing pipe (24), and the blowing pipe (24) is communicated with the air vent holes (23). The bottom of the blowing pipe (24) is connected with a piston rod (241). The outer wall of the piston rod (241) is slidably connected with a piston cylinder (242), and the piston cylinder (242) is communicated with the blowing pipe (24) through a through hole formed in the inner wall of the piston rod (241). The top of the outer wall of the piston cylinder (242) is sleeved with a support ring (243). A support block (244) is arranged below the piston cylinder (242), and the support block (244) is connected with the heat insulation sleeve (1). A spring (245) is connected between the support block (244) and the support ring (243).

2. The air duct electric heater according to claim 1, characterized in that: The number of the blowing pipes (24) is six groups. The spring (245) surrounds the outside of the piston cylinder (242). The shape of the filter net (21) is hemispherical.

3. The air duct electric heater according to claim 1, characterized in that: A ring-shaped impeller (25) is arranged at a position above the air vent ring (22) inside the filter pipe (2), and the ring-shaped impeller (25) is rotatably connected with the filter pipe (2).

4. The air duct electric heater according to claim 1, characterized in that: The top of the filter pipe (2) is connected with an air inlet pipe (3). The top of the air inlet pipe (3) is connected with a hair dryer (4).

5. The air duct electric heater according to claim 1, characterized in that: The bottom of the heat insulation sleeve (1) is connected with an air outlet (13). The top of the heat insulation sleeve (1) is connected with an air inlet (10), and the inner diameter of the air inlet (10) is smaller than the inner diameter of the heat insulation sleeve (1).

6. The air duct electric heater according to claim 1, wherein: The inner wall of the heat insulation sleeve (1) is connected with a metal sleeve (11). An electric heating pipe (12) is connected at the bottom position of the inner wall of the heat insulation sleeve (1), and the shape of the electric heating pipe (12) is spiral.

7. The air duct electric heater according to claim 4, wherein: The air inlet pipe (3) is on the same axis as the filter pipe (2) and the heat insulation sleeve (1). The inner diameter of the air vent holes (23) is larger than the inner diameter of the blowing pipes (24).

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