Water heater and its flow control valve

Abstract

We propose a flow control valve that can adjust the amount of water in a water heater to a desired level. [Solution] The present invention relates to a flow control valve (V) for a water heater, comprising a two-way valve for controlling the flow rate of cold or hot water. This flow control valve comprises a substantially bottomed cylindrical valve body (2) and a body (1) having a substantially cylindrical valve chamber (10) into which the valve body is rotatably fitted. The valve body has a circumferential wall portion (20) formed with an elongated hole (211) whose axial opening width changes continuously or intermittently along the circumferential direction, an opening (23) on one side of the circumferential wall portion, and a bottom portion (22) connected to the other side of the circumferential wall portion. The body has a flow hole (11) opening (111) on the inner circumferential surface of the valve chamber. The overlapping area of ​​the elongated hole and the flow hole changes according to the amount of rotation of the valve body, allowing for fine control of the amount of water flowing through the opening or the flow hole.

Description

Technical Field

[0006]

[0001] The present invention relates to a flow control valve or the like used in a water heater.

Background Art

[0002] A water heater (water supply heater) that heats cold water (e.g., tap water) and supplies hot water is used in homes and various facilities. There are instantaneous and storage-type water heaters, and fuels (gas, oil, etc.) and electricity are used as heat sources. Recently, with the demand for reducing environmental impact, a hot water supply system that stores and supplies hot water heated by a heat pump using a natural refrigerant (e.g., CO2) in a storage tank has also become widespread.

[0003] By the way, the adjustment of the amount of water and the water temperature in the water heater is performed through a valve provided in the water passage. Valves include a lift type that reciprocates (moves up and down) a valve body that opens and closes, and a drum type that rotates a valve body having an opening. The drum type valve is generally less expensive than the lift type valve and contributes to cost reduction of the water heater. There is a description of such a drum type valve for a water heater in the following patent documents.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Patent Document 1 proposes a flow rate adjustment valve in which a first opening and a second opening having different opening widths are arranged in the circumferential direction on a cylindrical valve body. This flow rate adjustment valve is always in a state of discharging water from any one of the openings to avoid excessive rotational torque acting on the valve body.

[0006] Both the first and second openings (slits) have a constant opening width in the circumferential direction and are not intended for active control of the flow rate. In other words, the control valve in Patent Document 1 is basically only intended for switching the flow rate between two predetermined positions (for example, between an "open" state and an effectively "closed" state).

[0007] This invention has been made in view of these circumstances, and aims to provide a new flow control valve, etc., that can control the amount of water flowing inside a water heater in a desired manner. [Means for solving the problem]

[0008] The inventors diligently researched how to solve this problem and conceived the idea of ​​freely controlling the water flow rate using a cylindrical valve body with elongated holes formed on its sides, where the opening width is varied along the circumferential direction in a desired manner. They then realized a flow control valve equipped with this valve body. By further developing this result, they completed the present invention described below.

[0009] Flow control valve for water heaters (1) The present invention relates to a flow control valve for a hot water heater comprising a two-way valve for controlling the flow rate of cold water or hot water, comprising a substantially bottomed cylindrical valve body and a body having a substantially cylindrical valve chamber into which the valve body is rotatably fitted, wherein the valve body has a circumferential wall portion formed with an elongated hole whose axial opening width changes continuously or intermittently along the circumferential direction, an opening on one side of the circumferential wall portion and a bottom portion connected to the other side of the circumferential wall portion, and the body has a flow hole opening on the inner circumferential surface of the valve chamber, and the flow control valve controls the amount of water flowing through the opening or the flow hole by changing the overlapping area of ​​the elongated hole and the flow hole according to the amount of rotation of the valve body.

[0010] (2) The flow control valve of the present invention (also simply called the "control valve") allows for the control (adjustment) of the flow rate of water (cold water or hot water) in the water heater to a desired manner while avoiding complexity of the valve structure.

[0011] The water flow rate is controlled by the control valve of the present invention as follows. Although the direction of water flow within the control valve is not specified, for convenience, the opening of the valve body will be referred to as the inlet side (supply side), and the flow hole of the main body as the outlet side (discharge side) for the appropriate explanation.

[0012] In the control valve of the present invention, the elongated holes formed in the circumferential wall of the substantially cylindrical valve body have varying axial opening widths along their circumferential direction. The main body has a flow hole that opens onto the inner cylindrical surface of the valve chamber into which the valve body is fitted.

[0013] When the valve body housed in the main body (valve chamber) is rotated relative to the valve body, the overlapping area (communicating opening area) between the elongated hole of the valve body and the flow hole (opening) of the main body changes according to the position (angle) of the valve body. This change in overlapping area changes the size of the water channel, and the amount of water flowing between the opening of the valve body and the flow hole of the main body is controlled.

[0014] Here, since the elongated hole can be made to have sufficient length along the circumferential direction, the overlapping area of ​​the elongated hole and the flow hole (opening) can also be adjusted according to the position (angle) of the valve body. Thus, with the control valve of the present invention, the degree of freedom in controlling the water volume in response to the rotation of the valve body is expanded, and the water volume can be precisely controlled in the desired manner while avoiding complexity and high cost of the valve structure.

[0015] Water heater The present invention can also be understood as a water heater equipped with the flow control valve described above. The water heater may be instantaneous or storage type. The means of heating (heating) the cold water is not limited. The heat source may be combustion heat, ambient air (atmosphere, air, etc.), radiant heat (sunlight, etc.), or electricity. The flow control valve may be used solely for adjusting the amount of water flowing in or out, or it may be used for adjusting the water temperature downstream.

[0016] "others" Unless otherwise specified, "x~y" in this specification includes the lower limit x and the upper limit y. Any number included in the various numerical values ​​or numerical ranges described in this specification may be used to create a new lower limit or upper limit, such as a range "a~b". [Brief explanation of the drawing]

[0017] [Figure 1] It is a front view showing an overview of a flow control valve (an example) for a water heater. [Figure 2] It is a front view showing the valve body incorporated in the flow control valve. [Figure 3A] It is a cross-sectional view taken along the line A-A of the valve body. [Figure 3B] It is a cross-sectional view taken along the line B-B of the valve body. [Figure 4] It is a development view of the outer peripheral surface of the valve body and a cross-sectional view taken along the line C-C thereof.

Embodiments for Carrying Out the Invention

[0018] One or more components arbitrarily selected from the matters described in this specification can be added to the configuration of the present invention described above. The components related to the method can become the components related to the object. Whether any embodiment is the best depends on the object, required performance, etc.

[0019] 《Valve Body》 (1) The valve body is a substantially bottomed cylindrical shape that is fitted into a substantially cylindrical valve chamber and rotates. The valve body has at least a cylindrical peripheral wall portion, a bottom portion continuous with one side of the peripheral wall portion, and an opening on the other side of the peripheral wall portion. Water flows through the inner and outer sides of the peripheral wall portion through a long hole that is a through hole.

[0020] The long hole has an opening width (length along the rotation axis / cylindrical axis) that continuously or intermittently changes from one end to the other end in the circumferential direction. The mode of change of the opening width (also referred to as the profile of the long hole) is not limited. The long hole may partially have a section where the opening width does not change. The change in the opening width may be linear or curved (exponential), and may be monotonic or increasing and decreasing.

[0021] The length from one end to the other end in the circumferential direction of the long hole (simply referred to as the "circumference of the long hole") is appropriately selected. The circumference of the long hole with respect to the entire circumference of the valve body (peripheral wall portion) is formed, for example, at a ratio of 120 / 360 to 300 / 360, 135 / 360 to 285 / 360 or 150 / 360 to 270 / 360. Such a ratio can also be understood as the formation angle of the long hole around the rotation axis. The formation angle is defined as the angle between the line segment (radius) connecting the virtual outer contour line of the long hole formed on the outer peripheral surface of the peripheral wall portion and the rotation center (cylindrical center) axis. Note that a part (middle) of the long hole is defined by the formation range according to the angle formed between the line segment (radius) connecting the virtual outer contour line of the long hole formed on the outer peripheral surface of the peripheral wall portion and the central axis and another line segment (radius).

[0022] When the formation angle of the entire long hole becomes excessive, it becomes difficult to maintain the shape of the valve body itself. When the formation angle of the long hole is too small, the adjustment (control) range of the flow rate also becomes small, and the control freedom degree decreases. In addition, the through holes (holes) having a conventional simple shape (circular shape, elliptical shape, rectangular shape, etc.) have a formation angle from one end to the other end in the circumferential direction of only about 45° to 90° at most.

[0023] (2) A grooved channel extending along the outer peripheral surface from at least one circumferential end of the long hole may be further provided. The grooved channel can finely supplement the flow rate control by the long hole at the initial or final stage of the flow rate control.

[0024] The start end of the grooved channel is continuous with one end of the long hole, but the end of the grooved channel may be continuous with the other end of the long hole or may be in the middle between both ends of the long hole. Different from the long hole, the grooved channel has a bottom and does not penetrate the peripheral wall portion. Therefore, the circumferential length of the grooved channel can be arbitrarily set between both ends of the long hole. For example, both circumferential ends of the long hole may be connected by the grooved channel.

[0025] Regardless of the cross-sectional shape of the grooved channel, the width (axial direction), depth (radial direction), etc. of the grooved channel may be appropriately adjusted according to the desired flow rate control. The grooved channel width may be, for example, 1 / 1 to 1 / 2 or 1 / 3 to 1 / 4 with respect to the opening width at the end of the long hole. The depth of the grooved channel may be, for example, 1 / 10 to 1 / 2 or 1 / 5 to 1 / 3 with respect to the thickness of the peripheral wall portion of the valve body.

[0026] (3) The valve body is rotationally driven, for example, via a pivot located on its bottom side. The pivot usually extends axially from the center of the bottom side and is connected to a drive source (e.g., a stepping motor). The drive source (stepping motor, etc.) that rotates the valve body may be considered an essential element of the control valve or an optional element, depending on the structure of the water heater and the control valve.

[0027] 《Main body》 The main body has a substantially cylindrical valve chamber in which the aforementioned valve body is rotatably fitted (housed). On the inner circumferential surface of the valve chamber, there is an opening (flow hole) positioned so as to overlap with the elongated hole of the valve body. The form (shape, size, arrangement, etc.) of this opening is set according to the profile of the elongated hole, the desired flow rate control, etc. For example, the overlapping area of ​​the elongated hole and the flow hole (opening) is maximized at the position of maximum flow rate, and the overlapping area of ​​the elongated hole and the flow hole (opening) is minimized at the position of minimum flow rate.

[0028] The roughly cylindrical valve chamber may be roughly bottomed. A shaft hole for inserting the pivot of the valve body may be provided at its bottom.

[0029] The valve body may have a port that connects to the piping of the water heater. The port may be integrally formed with the main body or may be assembled in a watertight manner. Each port communicates (connects) to the flow holes or valve chamber openings of the valve body, so that the control valve of the present invention functions as a two-way valve.

[0030] 《Material / Molding》 The valve body and main body are not limited by material, molding method, or whether or not they are processed. Using valve bodies and main bodies made from integrally molded resin parts by injection molding or the like allows for the provision of high-quality control valves at a low cost. [Examples]

[0031] The present invention will be explained in more detail, using a flow control valve used in a water heater as an example.

[0032] "overview" Figure 1 shows the main parts of a flow control valve V (simply referred to as "control valve V"), which is one embodiment of the present invention. The hatched areas in Figure 1 indicate cross-sections. The mounting direction (orientation) of the control valve V relative to the water heater (not shown) is not specified, but for convenience, the directions indicated by arrows in Figure 1 will be described as upward / downward or to the right (one side) / to the left (the other side). These will also apply to other figures.

[0033] The control valve V comprises a housing 1 (main body), a drum valve 2 (valve body) housed within the housing 1, a tubular joint 3 connected to the piping of the water heater (not shown), and a stepping motor 4 (drive source) that rotates the drum valve 2 in small increments. The housing 1 and the drum valve 2 are made from a single molded product formed by injection molding of synthetic resin.

[0034] The housing 1 comprises a cylindrical valve chamber 10, a port 11 (first port) that communicates with an opening 111 formed on the inner circumferential surface of the valve chamber 10 and protrudes vertically (upward) from the cylindrical side wall of the valve chamber 10, a port 13 (second port) that opens to one side (right) in the axial direction of the valve chamber 10, and a receiving portion 12 on the other side (left) of the valve chamber 10. The receiving portion 12 further has an annular guide groove 121 around the axis of rotation, a support projection 122, and a cylindrical bearing portion 123 on the other side.

[0035] The fitting 3 is fitted into one side of the port 13 via the O-ring 53 and is held watertight against the housing 1.

[0036] As shown in Figure 2, the drum valve 2 comprises a cylindrical peripheral wall portion 20, a control unit 21 formed in the circumferential direction of the peripheral wall portion 20, an opening 23 on one side of the peripheral wall portion 20, a bottom portion 22 on the other side of the peripheral wall portion 20, and a shaft portion 24 (pivot) extending from the bottom portion 22 to the other side (left).

[0037] The shaft portion 24 is fitted into the bearing portion 123 from one side (right side) and is pivotally supported to the housing 1 in a watertight manner via O-rings 542 and 543 fitted into seal grooves 242 and 243. The shaft portion 24 is also fitted into the rotor (not shown) of the stepping motor 4 from one side (right side), and rotational torque is transmitted via the serrations 241.

[0038] The drum valve 2 is supported on the other side (left side) of its bottom 22 by a support projection 122 with an arc-shaped cross-section, and a projection 221 (see Figure 3B) protruding from the bottom 22 to the other side is guided along a guide groove 121. In this way, the drum valve 2 rotates stably around its axis of rotation (central axis) even when subjected to fluctuations in the water pressure acting on it.

[0039] Valve body The control unit 21 of the drum valve 2 has an elongated hole 211 through which the cylindrical peripheral wall portion 20 is fitted in the radial direction, and a short open groove 212 extending circumferentially from one end of the elongated hole 211 along the outer surface of the peripheral wall portion 20.

[0040] Figure 3A shows the AA cross-section of the drum valve 2 shown in Figure 2, and Figure 3B shows its BB cross-section. Figure 4 also shows a plan view unfolded along the outer surface of the peripheral wall portion 20 and its CC cross-section.

[0041] The elongated hole 211 in this embodiment has three sections 211a, 211b, and 211c in which the opening width narrows in a substantially monotonous manner from one end to the other.

[0042] Section 211a is the region where the overlapping area between the opening 111 of port 11 and the elongated hole 211 is approximately the maximum. Section 211b is the region where the overlapping area decreases significantly along the circumferential direction (from one end to the other). Section 211c is the region where the overlapping area decreases gradually along the circumferential direction. The opening width of the elongated hole 211 changes curvilinearly in section 211b and linearly in section 211c.

[0043] As shown in Figures 3A and 4, the formation angles of sections 211a, 211b, and 211c around the central axis (cylindrical axis) of the peripheral wall portion 20 are α1, α2, and α3 (°), respectively. Expressed as a ratio to the total outer circumference of the peripheral wall portion 20, these are α1 / 360, α2 / 360, and α3 / 360, respectively. The formation angles can be adjusted arbitrarily. α1 + α2 + α3 is, for example, approximately 270 to 300°.

[0044] The groove 212, which is connected to the circumferential end of section 211c, is formed at an angle β around the central axis of the circumferential wall 20. β can be adjusted arbitrarily, but is typically around 10 to 30°. The depth of the groove 212 is, for example, about 1 / 3 to 1 / 4 of the thickness (radially) of the circumferential wall 20.

[0045] 《Operation》 When the drum valve 2 is assembled to the housing 1 and rotated by a stepping motor 4 in small increments, the opening area (overlapping area) of the control unit 21 (elongated hole 211 and groove 212) communicating with the opening 111 of port 11 gradually changes. Furthermore, the shape of the elongated hole 211 (the manner of opening width, the formation range) and the shape or presence or absence of the groove 212 can be freely adjusted or selected. In this way, using the control valve V, the amount of water flowing in the hot water heater between port 11 and port 13 (joint 3) can be finely adjusted to the desired manner. [Explanation of Symbols]

[0046] V Flow control valve 1. Enclosure (main unit) 10 valve chambers 11 Flow hole 111 Aperture 2. Drum valve (valve body) 20 Peripheral wall 211 Long hole 212 Open groove 22 Bottom 23 Opening

Claims

1. A flow control valve for a water heater, consisting of a two-way valve that controls the flow rate of cold or hot water, A valve body that is roughly cylindrical with a bottom, The valve body comprises a main body having a substantially cylindrical valve chamber into which the valve body is rotatably fitted, The valve body has a circumferential wall portion in which an elongated hole is formed along the circumferential direction, the axial opening width of which changes continuously or intermittently, an opening on one side of the circumferential wall portion, and a bottom portion connected to the other side of the circumferential wall portion. The main body has a flow hole opening on the inner circumferential surface of the valve chamber, A flow control valve that controls the amount of water flowing through the opening or the flow hole by changing the overlapping area of ​​the elongated hole and the flow hole according to the amount of rotation of the valve body.

2. The flow control valve according to claim 1, wherein the circumference of the elongated hole is 120 / 360 to 300 / 360 relative to the total circumference of the valve body.

3. The flow control valve according to claim 1, wherein the valve body has an open groove extending along the outer surface from at least one circumferential end of the elongated hole.

4. The flow control valve according to claim 1, wherein the valve body is made of a resin molded product.

5. The flow control valve according to claim 1, wherein the valve body has a pivot connected to a drive source on the bottom side.

6. The flow control valve according to claim 1, further comprising a stepping motor for rotating the valve body.

7. A water heater equipped with a flow control valve according to any one of claims 1 to 6.

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