A flow-through water heater

Abstract

This invention relates to the field of electric heating, and more particularly to a flow-through water heater. It includes a spiral water pipe and a heating pipe, with the heating pipe welded into the inner hole formed by the spiral shape of the water pipe. The two ends of the spiral water pipe serve as the inlet and outlet, respectively. The cross-section of the spiral water pipe is oblong, elliptical, triangular, or irregular, with the longer side of the pipe welded to the heating pipe. This invention achieves a more uniform and stable outlet water temperature by changing the shape of the water pipe cross-section, increasing the protrusions on the inner wall of the spiral water pipe, or adding flow-turbulence elements within the pipe. Through a variable pitch design, the surface temperature of the entire heating pipe is uniform, thermal stress is greatly reduced, and the lifespan of the heating pipe is extended.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electric heating, in particular to a flow-through water heater. BACKGROUND

[0002] In the prior art, the structure of the water heater is that the water pipe is wound into a spiral shape and welded with the electric heating pipe. The winding pitch of the water pipe is uniform, which has the disadvantage that the temperature of the heating pipe surface near the water outlet is relatively high, while the temperature of the heating pipe surface near the water inlet is relatively low, and the cold and hot ends of the heating pipe have thermal stress, which affects the service life.

[0003] In addition, since the position where the water pipe is welded with the heating pipe has the highest temperature, and the temperature away from the welding position is relatively low, the water flowing in the water pipe has temperature difference in the cross section perpendicular to the flow direction, and the water temperature is not well mixed during the entire flow process, resulting in uneven final water outlet temperature.

[0004] Invention patent content

[0005] The technical problem to be solved by the present application is to overcome the shortcomings of the prior art and provide a flow-through water heater.

[0006] To solve the technical problem, the technical solution adopted by the present application is:

[0007] A flow-through water heater is provided, which includes a spiral water pipe and a heating pipe. The heating pipe is welded in the inner hole formed by the spiral shape of the spiral water pipe. The two ends of the spiral water pipe are respectively used as the water inlet and the water outlet. The cross section of the spiral water pipe body is in the shape of a waist, an ellipse, a triangle or an irregular shape. The pipe body on the longer side of the cross section is welded with the heating pipe.

[0008] As an improvement, the spiral water pipe is divided into a water inlet section and a water outlet section in the direction from the water inlet to the water outlet and along the inner hole axis. The pitch of the water outlet section is smaller than that of the water inlet section.

[0009] As an improvement, the inner wall of the spiral water pipe body is provided with a plurality of protrusions or a turbulence element is arranged in the pipe body.

[0010] As an improvement, the turbulence element has a spiral line, and the spiral line of the turbulence element is parallel or coincides with the welding line of the water pipe.

[0011] As an improvement, a bracket is arranged at the water outlet end of the spiral water pipe, and the bracket is provided with a mounting hole and a bent portion for mounting a temperature controller.

[0012] The principle of the present application is:

[0013] 1. In this invention, different cross-sectional shapes of the water pipes are set to increase the welding area between the water pipes and the heating pipes, thereby reducing the temperature at the welding position, narrowing the temperature difference between the water near the welding point and the water far from the welding point, and weakening the unevenness of the water temperature.

[0014] 2. In this invention, by increasing the protrusions on the inner wall of the spiral water pipe or by adding turbulence elements inside the pipe, the turbulence in the water flow can be increased, the development of the boundary layer can be cut off, the convective heat transfer can be enhanced, and the water near the weld can be fully mixed with the water far from the weld, thus reducing the water temperature inhomogeneity. Increasing the protrusions on the inner wall of the spiral water pipe can also expand the surface area and increase the heat exchange area, reduce the temperature at the weld position, reduce the temperature difference between the water near the weld and the water far from the weld, and further reduce the water temperature inhomogeneity.

[0015] 3. The variable pitch design of the spiral water pipe in this invention ensures a uniform temperature across the entire heating pipe surface, reducing thermal stress. As water flows through the heater, it continuously absorbs heat, causing its temperature to gradually increase. The closer to the outlet, the higher the water temperature, and the weaker the water's ability to cool the heating pipe surface, resulting in an even higher surface temperature. Therefore, a denser pitch design near the outlet increases the length of this section of pipe, thus increasing the contact area between the water pipe and the heating pipe, allowing the heating pipe surface temperature to drop to the desired operating temperature range. Conversely, a wider pitch design near the outlet reduces the length of this section of pipe, thus reducing the contact area between the water pipe and the heating pipe, allowing the heating pipe surface temperature to rise to the desired operating temperature range. Furthermore, this design achieves the desired heating pipe surface temperature using minimal pipe material, reducing unnecessary material waste. Through variable pitch design, the temperature of the entire heating tube surface is uniform, reducing thermal stress.

[0016] Compared with the prior art, the beneficial effects of this invention patent are as follows:

[0017] 1. By changing the shape of the water pipe cross-section, increasing the protrusions on the inner wall of the spiral water pipe, or adding turbulence-inducing elements inside the pipe, the outlet water temperature can be made more uniform and stable.

[0018] 2. Through the variable pitch design, the temperature of the entire heating tube surface is uniform, the thermal stress is greatly reduced, and the heating tube has a longer service life. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a device in the prior art;

[0020] Figure 2 This is a schematic diagram of the cross-sectional shape of the spiral water pipe in the prior art;

[0021] Figure 3is a structural schematic diagram of the present application;

[0022] Figure 4 is a cross-sectional shape schematic diagram of a spiral water pipe in embodiment 1 of the present application;

[0023] Figure 5 is a cross-sectional shape schematic diagram of a spiral water pipe in embodiment 2 of the present application;

[0024] Figure 6 is a cross-sectional shape schematic diagram of another spiral water pipe in embodiment 1 of the present application.

[0025] Wherein, 1-heating pipe; 2-spiral water pipe; 3-bracket. DETAILED DESCRIPTION

[0026] The present application will be further described below in conjunction with the drawings:

[0027] As shown in Figure 1 , 2 , a water heater in the prior art comprises a spiral water pipe 2 and a heating pipe 1, the heating pipe 1 is welded in the inner hole formed by the spiral shape of the spiral water pipe 2, the two ends of the spiral water pipe 2 are led out perpendicularly to the heating pipe 1 and serve as the water inlet and the water outlet respectively, the pitch of the entire spiral water pipe 2 is uniformly distributed, the same at each place, and the cross section of the spiral water pipe 2 is circular.

[0028] As shown in Figure 3 , a through-flow type water heater of the present application comprises a spiral water pipe 2 and a heating pipe 1, the heating pipe 1 is welded in the inner hole formed by the spiral shape of the spiral water pipe 2, the two ends of the spiral water pipe 2 are led out and serve as the water inlet and the water outlet respectively; the spiral water pipe 2 is divided into a water inlet section and a water outlet section in the direction from the water inlet to the water outlet and along the inner hole axis; the pitch of the water outlet section is smaller than that of the water inlet section.

[0029] It should be noted that the pitch of the spiral water pipe inside the water outlet section gradually decreases, which can be gradually reduced along the heating pipe axis from the water inlet direction to the water outlet direction, or the spiral water pipe 2 can be divided into several sections with the same number of turns, the pitch of each section is the same, and the pitch decreases between adjacent sections. The numerical value of the pitch can be continuous or discontinuous. The pitch of the spiral water pipe in the water inlet section can be equal or unequal, and when the pitch is unequal, it also gradually decreases along the water inlet direction to the water outlet direction.

[0030] The end of the spiral water pipe 2 at the water outlet is provided with a bracket 3, the bracket 3 is provided with mounting holes and a bent part for mounting a temperature controller.

[0031] Embodiment 1, as shown in Figure 4 , the cross section of the spiral water pipe 2 is in the shape of a waist, in addition to which it can also be in the shape of an ellipse, a triangle (as shown in Figure 6As shown in the figure, or an irregular shape, the pipe body on the longer side of the cross-section is welded to the heating pipe 1. Taking the waist-shaped cross-section as an example, the waist shape includes two horizontal straight lines and arcs connecting the two ends of the straight lines respectively. The longer side refers to the side in the cross-section that maximizes the contact area between the spiral water pipe 2 and the heating pipe 1, that is, the horizontal straight line side in the waist shape.

[0032] Example 2, as Figure 5 As shown, the inner wall of the spiral water pipe 2, on the side welded to the heating pipe, has several protrusions or flow-turbating elements inside the pipe. These elements are used to increase turbulence in the water flow, interrupt the development of the boundary layer, enhance convective heat transfer, and ensure thorough mixing of water near the weld with water far from the weld. The protrusions have a toothed or arc-shaped cross-section, and the flow-turbating elements have a spiral line that is parallel to or coincides with the weld line of the water pipe.

[0033] In this embodiment, the cross-sectional shape of the spiral water pipe 2 and the protrusion shape of the inner wall are designed in combination. In other embodiments, the cross-sectional shape of the spiral water pipe 2 and the protrusion shape of the inner wall can be designed in other combinations or individually according to the actual situation.

[0034] Finally, it should be noted that the above examples are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of this invention should be considered within the scope of protection of this invention.

Claims

1. A flow-through water heater comprising a spiral water pipe and a heating pipe, the heating pipe being welded in a hole formed in a spiral shape of the spiral water pipe, both ends of the spiral water pipe serving as a water inlet and a water outlet, respectively; characterized in that, The pipe body section of the spiral water pipe is in the shape of a waist, an ellipse or a triangle, and the long side of the section corresponds to the pipe body welded with the heating pipe; the long side of the section refers to the side corresponding in the section when the pipe body of the spiral water pipe has the maximum contact area with the heating pipe; The spiral water pipe is divided into a water inlet section and a water outlet section in the direction from the water inlet to the water outlet and along the inner hole axis, and the pitch of the spiral water pipe in the water outlet section is smaller than the pitch in the water inlet section; The spiral water pipe is provided with a support at the water outlet end, and the support is provided with a mounting hole and a bent part for mounting a temperature controller.

2. The flow-through water heater of claim 1, wherein The inner wall of the pipe body of the spiral water pipe is provided with a plurality of protrusions on the side welded with the heating pipe or is provided with a turbulence element inside the pipe body.

3. A flow-through water heater as claimed in claim 2, wherein The turbulence element has a spiral line, and the spiral line of the turbulence element is parallel to or coincides with the welding line of the water pipe.

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