Hot air gun core and hot air gun having the same

Abstract

The present invention relates to a core body and a hot air gun having the same. The core body includes a base, several brackets disposed on the base, and heating wires. The brackets include a front bracket and a rear bracket arranged along the axial direction of the base. The rear bracket is provided with an axially penetrating air guiding channel, and the air guiding channel is provided with an outlet end extending to at least one side of the front bracket, and the outlet end is disposed opposite to the heating wires. By dividing the air flow flowing through the core body into two parts, the first part of the air flow flows along the outer circle of the core body, and the second part of the air flow directly blows towards the heating wires wound around the front end from the air guiding channel after being sucked into the casing. The second part of the air flow with a lower temperature is mixed with the first part of the air flow with a higher temperature, avoiding heat accumulation and causing the temperature of the front-end heating wires to be too high, making the temperature of the overall core body more uniform. On the one hand, the utilization rate of the heat energy of the heating wires is improved, ensuring the output power. On the other hand, the uniform distribution of the core body temperature greatly extends the overall service life of the heating wires.

Description

Technical Field

[0001] The present invention relates to the field of power tools, and particularly to a hot air gun core and a hot air gun having the core.

Background Art

[0002] A hot air gun is a power tool that generates high temperature by a heat-generating core and blows out the high-temperature air flow through a fan assembly to perform a heating operation on components. The core generally includes a base composed of several insulating plates spliced together, a heating wire wound around the base, and a bracket disposed in the space surrounded by adjacent insulating plates and the heating wire; the outer sides of the base and the bracket are provided with winding notches for the heating wire to be embedded.

[0003] Since the high-temperature air flow generated in the hot air gun flows from the rear to the front, cold air is input from one end, continuously heated during the process and then output from the other end, taking out the heat of the core to form hot air. The heat accumulates step by step forward with the number of turns of the heating wire, which causes the heating wire at the front end to be heated much more than the heating wire at the rear end, and thus the heating wire at the front end is prone to thermal fatigue and damage, shortening the service life.

[0004] With the development of industry, the output power of the hot air gun is getting larger and larger. It is indeed necessary to provide an improved hot air gun to overcome the defects existing in the prior art.

Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a hot air gun core and a hot air gun having the core that improve safety and reliability.

[0006] The present invention can adopt the following technical solutions to solve the problems of the prior art: A hot air gun core includes a base, several brackets and a heating wire disposed on the base. The base includes several insulating plates that support each other and several installation spaces located between the insulating plates. The brackets are disposed in the installation spaces, and the heating wire is wound around the brackets. The brackets include a front bracket and a rear bracket arranged along the axial direction of the base. The rear bracket is provided with an axially penetrating air guiding channel, and the air guiding channel is provided with an outlet end extending to at least one side of the front bracket, and the outlet end is disposed opposite to the heating wire.

[0007] A further improvement scheme is: The rear bracket is provided with an axially penetrating through hole, and the through hole forms the air guiding channel. The front bracket partially blocks the through hole, so that the outlet end of the air guiding channel is arranged to open towards both sides.

[0008] A further improvement scheme is: The connection part between the front bracket and the rear bracket is in a wedge-shaped structure, and the tip of the wedge-shaped structure is collinear with the midline of the through hole.

[0009] A further improvement solution is that the wedge-shaped structure has two air guiding inclined surfaces oppositely arranged on two side walls of the front bracket, and the air guiding inclined surfaces are curved surfaces.

[0010] A further improvement solution is that the projection shape of the air guiding inclined surface in the axial direction of the front bracket is a cone, and the small end of the cone faces away from the rear bracket.

[0011] A further improvement solution is that the small end of the cone extends to the lower part of the last turn of the heating wire wound around the front bracket.

[0012] A further improvement solution is that one end of the front bracket away from the rear bracket is provided with a guiding part, the guiding part is obliquely arranged on the side wall of the front bracket, and the guiding part extends from the upper end side of the front bracket towards the front end side of the front bracket.

[0013] A further improvement solution is that one end of the air guiding channel away from the front bracket forms an air flow inlet, and the diameter of the air flow inlet is larger than the diameter of the air guiding channel.

[0014] A further improvement solution is that both the base and the bracket include a plurality of receiving parts protruding radially outwards, the end surfaces of the receiving parts are recessed inwards to form a plurality of winding notches arranged at intervals for the heating wire to be embedded, and the protruding heights of the plurality of receiving parts are inconsistent.

[0015] The present invention also provides a hot air gun, which includes a housing for receiving a hot air gun core body and a motor installed in the housing; the base is fixed on the housing, and the rear bracket is located between the motor and the front bracket.

[0016] Compared with the prior art, the present invention has the following beneficial effects: by dividing the air flow flowing through the core body into two parts, the first part of the air flow flows along the outer circle of the core body, and the second part of the air flow directly blows towards the heating wire wound at the front end from the air guiding channel after being inhaled into the housing. The second part of the air flow with a lower temperature is mixed with the first part of the air flow with a higher temperature, avoiding heat accumulation and causing the temperature of the front-end heating wire to be too high, making the temperature of the whole core body more uniform. On the one hand, the utilization rate of the heat energy of the heating wire is improved, and the output power is guaranteed. On the other hand, the uniform distribution of the core body temperature greatly extends the overall service life of the heating wire.

Description of the Drawings

[0017] The following further describes in detail the specific embodiments of the present invention with reference to the drawings:

[0018] Figure 1 It shows a schematic structural diagram of a hot air gun core body of a preferred embodiment of the present invention;

[0019] Figure 2 It shows a schematic structural diagram of the bracket;

[0020] Figure 3 Shown is a schematic structural view of another perspective of the bracket;

[0021] Figure 4 Shown as Figure 3 the front view;

[0022] Figure 5 Shown as Figure 3 the side view;

[0023] Figure 6 Shown as Figure 3 the sectional view;

[0024] Figure 7 Shown as the assembly schematic diagram of the bracket;

[0025] Figure 8 Shown as the overall machine schematic diagram of the hot air gun.

[0026] Meanings of the reference numerals in the figure:

[0027] 1, core body; 11, base; 2, bracket

[0028] 21, front bracket; 211, air guiding inclined plane; 212, small end

[0029] 213, guiding part; 22, rear bracket; 221, air guiding channel

[0030] 222, air inlet; 223, air outlet gap; 3, heating wire

[0031] 4, receiving part; 41, wire winding notch; 5, housing

[0032] 51, air outlet; 6, motor assembly; 7, fan assembly

[0033] 8, holding part; 9, air duct

Detailed implementation manners

[0034] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of 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.

[0035] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0036] Please refer to Figures 1 - 3 and Figure 7 As shown, the hot air gun core 1 provided by the preferred embodiment of the present invention includes a base 11 composed of a plurality of insulating plates spliced together and a bracket 2 disposed between adjacent insulating plates. The base 11 is preferably made of mica plate or ceramic material, and the bracket 2 is preferably made of ceramic material, having the advantages of good insulation and good heat resistance. The inner sides of the plurality of insulating plates are connected to each other to form the base 11, so that the base 11 forms a plurality of uniformly sized accommodating spaces in the circumferential direction, and each accommodating space is correspondingly provided with a bracket 2. For example, when the base 11 is spliced by 3 insulating plates, the base 11 forms a Y-shaped cross-section with an accommodating space for installing 3 brackets; when the base 11 is spliced by 4 insulating plates, the base 11 forms a cross-shaped cross-section with an accommodating space for installing 4 brackets. The number of insulating plates is set according to actual needs as long as it can ensure the structural strength, and no detailed introduction will be given here due to space limitations.

[0037] The heating wire 3 is spirally wound around the base 11 and the bracket 2 and can generate heat when energized. During operation, the motor assembly 6 in the hot air gun drives the fan assembly 7 to rotate, so as to suck the external air flow into the casing 5 from the air inlet. When the air flow passes through the core 1, the heat continuously generated by heating the heating wire 3 is discharged from the air outlet 51 to form hot air. In the prior art, the heat distribution of the hot air gun core gradually increases forward with the increase of the number of turns of the heating wire from the starting end to the ending end of the heating wire. The heating wire at the front end is heated much more than the heating wire at the rear end, resulting in the heating wire at the front end being prone to thermal fatigue and damage, shortening the service life. To overcome the above defects, in the preferred embodiment of the present invention, the bracket 2 includes a front bracket 21 and a rear bracket 22 arranged along the axial direction of the base 11. The meanings of "front" and "rear" refer to that when the user holds the hot air gun, the direction in which the air flow is sucked into the hot air gun is the rear, and the direction in which the air flow is heated and discharged by the hot air gun is the front. Refer to Figure 5 and Figure 6As shown in the figure, the rear bracket 22 is provided with a hollow structure, which has an axial through-hole to form an air guiding channel 221; the air guiding channel 221 is provided with an outlet end extending to at least one side of the front bracket 21, and the outlet end is arranged opposite to the heating wire 3. The air flow flowing through the core body 1 will pass through the air guiding channel 221 and the outside of the rear bracket 22 at the same time, and blow towards the heating wire arranged opposite to the outlet end of the air guiding channel 221, so as to avoid heat accumulation. Specifically, the front bracket 21 is connected to the front end of the rear bracket 22 and partially blocks the through-hole, so that the outlet end of the air guiding channel 221 is arranged to open towards both sides. When the hot air gun works, the air flow flowing through the core body 1 is divided into two parts: the first part of the air flow flows along the outer circle of the core body 1, carries the heat from the starting end of the heating wire on the rear bracket 22 to the end of the heating wire on the front bracket 21, and is discharged from the air outlet 51. The second part of the air flow directly flows towards the heating wire wound on the front bracket 21 from the air guiding channel 221 through the air outlet gap 223 after being inhaled into the housing 5, that is, the second part of the air flow with a lower temperature is mixed with the first part of the air flow with a higher temperature here, avoiding the temperature of the front-end heating wire being too high due to heat accumulation, making the temperature of the whole core body 1 more uniform, and thus prolonging the overall service life of the heating wire 3.

[0038] As an implementation manner, the ratio of the number of turns of the heating wire wound around the rear bracket 22 to the number of turns of the heating wire on the front bracket 21 is 4:3. The number of turns of the heating wire on the rear bracket 22 is relatively large to ensure the heating power, and the number of turns of the heating wire on the front bracket 21 is relatively small to take into account the service life, so as to achieve the balance of the heating power and the service life of the whole core body 1. It should be noted that the present invention does not specifically limit the number of turns of the heating wire 3, and can be adaptively adjusted according to needs in actual applications.

[0039] In a preferred embodiment of the present invention, the connection part between the front bracket 21 and the rear bracket 22 is in a wedge-shaped structure. The wedge-shaped structure divides the outlet end of the air guiding channel 221 into at least two air outlet gaps 223. Specifically, the rear end of the front bracket 21 is connected to the front end of the rear bracket 22. The left and right sides of the rear end of the front bracket 21 are provided with two symmetrically arranged air guiding inclined surfaces 211. The air guiding inclined surfaces 211 are further set as curved surfaces. The projection shape of the air guiding inclined surfaces 211 on the side surface of the front bracket 21 is a cone, and the small end 212 of the cone faces away from the rear bracket 22 and extends below the last turn of the heating wire wound around the front bracket 21. By setting the connection part between the front bracket 21 and the rear bracket 22 as a wedge-shaped structure with a conical air guiding inclined surface, a good guiding effect on the air flow can be formed, thereby accelerating the air flow and facilitating the mixing of the first part of the air flow and the second part of the air flow. In a further embodiment of the present invention, the tip of the wedge-shaped structure is collinear with the central dividing line of the through-hole, dividing the outlet end of the air guiding channel into two air outlet gaps 223 of the same size, so that the air volume coming out of the two air outlet gaps 223 is the same, to ensure uniform heat distribution around the front bracket 21.

[0040] As an implementation manner, refer toFigure 2 , Figure 3 and Figure 4 As shown in Figure 2 , Figure 3 and Figure 4 , a guiding portion 213 is provided on the side wall of one end of the front bracket 21 away from the rear bracket 22. The guiding portion 213 is arranged obliquely with respect to the front bracket 21, and the guiding portion 213 extends from the upper end side of the front bracket 21 toward the front end side. With such an arrangement, the air flow is blown away from the front bracket 21 via the guiding portion 213, the flow of the air flow on the front bracket 21 is smoother, and at the same time, the heat dissipation performance of the core body 1 is improved. In this embodiment, the inclination angle of the guiding portion 213 with respect to the front bracket 21 is 10 degrees. The air guiding inclined surface 211 and the guiding portion 213 intersect at least partially in the axial direction of the front bracket 21, which improves the air flow velocity.

[0041] In a preferred embodiment of the present invention, the base 11 is formed by splicing 4 insulating plates at 90 degrees to form a cross shape, and the four brackets 2 are respectively received in four accommodation spaces formed by splicing the insulating plates. The bracket 2 includes a front bracket 21 and a rear bracket 22 arranged along the axial direction, as well as a positioning seat arranged along the radial direction and a receiving portion 4 protruding outward from the surface of the positioning seat. The end surface of the receiving portion 4 is recessed inward to form a plurality of winding notches 41 for the heating wire 3 to be embedded. The cross section of the positioning seat of the rear bracket 22 is fan-shaped, having two side walls arranged at an acute angle and an arc-shaped top wall connecting the two side walls. The space formed by surrounding the two side walls and the arc-shaped top wall constitutes a wind guiding channel 221. The included angle between the two side walls is preferably 85 degrees - 90 degrees to prevent the positioning seat from moving around after being assembled into the accommodation space, so as to obtain a more reliable fixation and increase the assembly stability. A plurality of receiving portions 4 protrude outward from the arc-shaped top wall of the positioning seat, and the protruding heights of the plurality of receiving portions 4 are different to increase the air flow and improve the heat dissipation performance of the core body 1.

[0042] As an implementation manner, referring to Figure 4 , Figure 5 and Figure 6 As shown in Figure 4 , Figure 5 and Figure 6 , one end of the wind guiding channel 221 away from the front bracket 21 constitutes an air flow inlet 222. The inner pipe diameter at the air flow inlet 222 is larger than the inner pipe diameter of the wind guiding channel 221 to increase the air intake amount entering the wind guiding channel 221. At the same time, the outer pipe diameter at the air flow inlet 222 is also set to be larger than the outer pipe diameter of the wind guiding channel 221 to further increase the assembly stability.

[0043] Referring to Figure 8As shown, an embodiment of the present invention also relates to a hot air gun having the above-mentioned core body. The hot air gun includes a housing 5, a motor assembly 6 installed in the housing 5, a fan assembly 7 driven by the motor assembly 6, a core body 1 provided at the front end of the housing 5, a grip portion 8 extending downward from the lower end of the housing 5, a control assembly installed in the grip portion, and a switch assembly installed on the grip portion 8. The motor assembly 6 is located at the rear end of the housing 5, the core body 1 is installed inside the front end of the housing 5, and the fan assembly 7 is located between the motor assembly 6 and the core body 1; the grip portion 8 is located at the end of the housing 5 near the motor assembly 6, and the motor assembly 6, the core body 1, and the switch assembly are all electrically connected to the control assembly. In actual use, the user presses the switch assembly to start the motor assembly 6 and drive the fan assembly 7 to rotate. While the fan assembly 7 is rotating at a high speed, the heat generated by the core body 1 is carried by the air flow and blown out of the hot air gun to heat the component.

[0044] In a preferred embodiment of the present invention, the above-mentioned housing 5 includes an air inlet opened at the rear end and an air outlet 51 opened at the front end of the core body 1. The motor assembly 6 drives the fan assembly 7 to rotate to suck external air flow into the housing through the air inlet and discharge the heat generated by the core body 1 outwards from the air outlet 51.

[0045] The above-mentioned hot air gun further includes a protection portion (not shown in the figure) provided on the front side of the grip portion 8. The protection portion is connected between the bottom of the grip portion 8 and the lower end of the housing 5. The protection portion, the housing 5, and the grip portion 8 enclose a grip area for receiving the user's finger. The protection portion can prevent the user from directly touching the part of the housing where the core body is located during use, thereby avoiding the user being scalded.

[0046] As an embodiment, the above-mentioned housing 5 includes a heat dissipation opening (not shown in the figure) opened at the front end. The heat dissipation opening corresponds to the position of the core body 1 and is spaced apart from the heating wire 3 to further prevent the user from being scalded.

[0047] The above-mentioned hot air gun further includes a wind tube 9 sleeved on the outer periphery of the heating wire 3. The fan assembly 7 includes a wind blade connected to the motor assembly 6 and a flow guiding cover for receiving the wind blade. The wind tube 9 is connected to the flow guiding cover, and the air flow generated by the wind blade flows between the flow guiding cover and the wind tube 9 to reduce the loss of air volume.

[0048] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0049] Although embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A hot air gun core body, comprising a base, several brackets disposed on the base, and heating wires. The base includes several insulating plates that support each other and several installation spaces located between the insulating plates. The brackets are disposed in the installation spaces, and the heating wires are wound around the brackets. It is characterized in that: The brackets include a front bracket and a rear bracket arranged along the axial direction of the base. The rear bracket is a hollow structure and has an axial through hole to form a wind guiding channel. The wind guiding channel is provided with an outlet end extending to at least one side of the front bracket, and the outlet end is disposed opposite to the heating wires. The connection part where the front bracket is connected to the rear bracket is a wedge-shaped structure, and the wedge-shaped structure divides the outlet end of the wind guiding channel into at least two air outlet gaps, and the air flow directly flows from the wind guiding channel through the air outlet gaps to the heating wires wound around the front bracket.

2. The hot air gun core body according to claim 1, It is characterized in that: The front bracket partially shields the through hole, so that the outlet end of the wind guiding channel is arranged to open towards both sides.

3. The hot air gun core body according to claim 1, It is characterized in that: The tip of the wedge-shaped structure is collinear with the midline of the through hole.

4. The hot air gun core body according to claim 3, It is characterized in that: The wedge-shaped structure has two wind guiding inclined surfaces oppositely disposed on two side walls of the front bracket, and the wind guiding inclined surfaces are curved surfaces.

5. The hot air gun core body according to claim 4, It is characterized in that: The projection shape of the wind guiding inclined surface in the axial direction of the front bracket is a cone, and the small end of the cone faces away from the rear bracket.

6. The hot air gun core body according to claim 5, It is characterized in that: The small end of the cone extends to the lower side of the last turn of the heating wire wound around the front bracket.

7. The hot air gun core body according to claim 1, It is characterized in that: One end of the front bracket far from the rear bracket is provided with a guiding part, and the guiding part is inclined on the side wall of the front bracket, and the guiding part extends from the upper end side of the front bracket towards the front end side of the front bracket.

8. The hot air gun core body according to claim 1, It is characterized in that: One end of the wind guiding channel far from the front bracket forms an air flow inlet, and the diameter of the air flow inlet is larger than the diameter of the wind guiding channel.

9. The hot air gun core body according to claim 1, It is characterized in that: Both the base and the brackets include a plurality of receiving parts protruding radially outwards. The end faces of the receiving parts are recessed inwards to form a plurality of winding notches arranged at intervals for the heating wires to be embedded. The protruding heights of the plurality of receiving parts are inconsistent.

10. A hot air gun, which has a housing for receiving the hot air gun core body and a motor installed in the housing; It is characterized in that: It has the hot air gun core body according to any one of claims 1-9, and the base is fixed on the housing, and the rear bracket is located between the motor and the front bracket.

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