JP7785463B2 - Storage-type water heater and its shipping method - Google Patents

Description

This disclosure relates to a storage-type water heater and its shipping method.

In a known hot water storage type water heater, hot water stored in a hot water storage tank is discharged from a hot water supply outlet to an external hot water supply pipe. The hot water supplied through the external hot water supply pipe is released from a mixer faucet installed inside the home. When replacing the mixer faucet inside the home, for example, it is necessary to stop the supply of hot water from the tank unit. For this reason, a commonly known configuration is to install a hot water stop valve midway along the external hot water supply pipe (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 7-158977

As in Patent Document 1, in order to install a hot water stop valve in the middle of the external hot water supply piping, the contractor must prepare and install the hot water stop valve, incurring additional costs. For this reason, there is a possibility that a customer may choose not to install a hot water stop valve. Furthermore, depending on the type of hot water stop valve prepared, the diameter of the hot water supply piping may be reduced, which may affect the flow rate, making it impossible to ensure the expected flow rate. As a result, there are concerns that users may complain about poor hot water flow, and other issues that depend on the construction.

This disclosure has been made to solve the problems described above, and aims to provide a storage-type hot water heater and its shipping method that ensures consistent hot water supply performance without being affected by installation and allows for efficient replacement of in-home mixer faucets.

The hot water storage type water heater of the present disclosure comprises a hot water storage tank, an outer case that houses the hot water storage tank, a water supply inlet that is arranged with one end exposed outside the outer case and can be connected to an external water supply pipe, a water supply pipe that connects the water supply inlet to the hot water storage tank and sends water supplied from the external water supply pipe into the hot water storage tank, a mixing valve that mixes hot water from the hot water storage tank and water from the water supply pipe, a hot water supply inlet that is arranged with one end exposed outside the outer case and can be connected to an external hot water supply pipe, a hot water outlet flow path that sends hot water from the mixing valve to the hot water supply inlet, and a water stop mechanism that is provided in the hot water supply inlet and can stop the flow in the hot water outlet flow path , the hot water supply inlet is arranged in a riser part of the outer case and the water stop mechanism is composed of a ball valve or a butterfly valve, and the hot water that passes through the external hot water supply pipe is sent to a mixing faucet inside the home.
Furthermore, the shipping method for a storage type water heater according to the present disclosure involves shipping the storage type water heater from a factory with the water shutoff mechanism in an open state.

This disclosure makes it possible to provide a storage-type hot water heater and its shipping method that ensures consistent hot water supply performance without being affected by installation and allows for efficient replacement of in-home mixer faucets.

1 is a diagram showing a storage type hot water heater according to a first embodiment; A cross-sectional view showing the structure of the hot water outlet of the hot water storage type water heater in embodiment 1. FIG. 3 is an enlarged cross-sectional view of a part of FIG. 2. An oblique view showing the structure of the hot water outlet of the hot water storage type water heater in embodiment 1. FIG. 10 is a cross-sectional view showing an example of a hot water outlet having a water shutoff mechanism formed by a ball valve.

The following describes the embodiments with reference to the drawings. Common or corresponding elements in each drawing are given the same reference numerals, and their description will be simplified or omitted. Note that when angles are mentioned in this disclosure, if there are a reflex angle and a minor angle whose sum is 360°, this generally refers to the minor angle, and if there are an acute angle and an obtuse angle whose sum is 180°, this generally refers to the acute angle.

Embodiment 1.
FIG. 1 is a diagram showing a hot water storage type water heater 1 according to a first embodiment. The hot water storage type water heater 1 includes a hot water storage tank 10 and an outer case 2 that houses the hot water storage tank 10. The hot water storage tank 10 is, for example, cylindrical, with its central axis parallel to a vertical line. The outer case 2 has a substantially rectangular parallelepiped outer shape. The outer case 2 and the equipment housed within the outer case 2 are also referred to as a tank unit. The hot water storage type water heater 1 may further include a heating device (not shown) for heating hot water stored in the hot water storage tank 10. The heating device may be, for example, an electric heater installed within the hot water storage tank 10, or a heating device separate from the tank unit. The heating device may be, for example, a heat pump unit, a solar water heater, a device that utilizes waste heat from a fuel cell, or a device that utilizes a combination of multiple heat sources.

A water supply port 22 is attached to the outer case 2. One end of the water supply port 22 is positioned so that it is exposed to the outside of the outer case 2, and the other end of the water supply port 22 is located inside the outer case 2. The water supply port 22 can be connected to an external water supply pipe 21 that extends to the outside of the outer case 2. City water is supplied to the storage-type water heater 1 through the external water supply pipe 21.

A hot water inlet 42 is attached to the exterior case 2. One end of the hot water inlet 42 is positioned so that it is exposed to the outside of the exterior case 2, and the other end of the hot water inlet 42 is located inside the exterior case 2. The hot water inlet 42 can be connected to an external hot water supply pipe 41 that extends to the outside of the exterior case 2. Hot water generated by the hot water storage type water heater 1 is sent through the external hot water supply pipe 41 to a mixer tap, such as a shower, sink, or washbasin, within the home. The water inlet 22 and the hot water inlet 42 may be positioned in a riser portion of the exterior case 2. In that case, the water inlet 22 and the hot water inlet 42 may be covered by a cover (not shown) that can be attached to the riser portion and removed.

The tank piping 3, water supply piping 20, mixing valve 30, and hot water outlet flow path 40 are provided inside the outer case 2. The water supply piping 20 connects the water supply port 22 to the bottom of the hot water storage tank 10, and sends water supplied from the external water supply piping 21 into the hot water storage tank 10.

The water supply pipe 20 branches into two and is also connected to the mixing valve 30. The tank pipe 3 connects the top of the hot water storage tank 10 to the mixing valve 30. The mixing valve 30 mixes the hot water that has passed through the tank pipe 3 from the hot water storage tank 10 with the water from the water supply pipe 20. The hot water outlet flow path 40 connects the outlet of the mixing valve 30 to the hot water supply port 42. The hot water from the mixing valve 30 flows through the hot water outlet flow path 40 and the hot water supply port 42 into the external hot water supply pipe 41.

A water stop mechanism 45 capable of stopping the flow of the hot water outlet flow path 40 is provided on the hot water supply outlet 42. The water stop mechanism 45 is a mechanism for preventing hot water from continuing to flow from the hot water storage tank 10 through the hot water supply outlet 42 when replacing a home's mixer faucet. If the hot water supply outlet 42 did not have a water stop mechanism 45, hot water would continue to flow from the hot water supply outlet 42 even if the city water supply to the water supply inlet 22 was cut off, so a certain amount of hot water would need to be drained from the hot water storage tank 10 in advance. In contrast, with this embodiment, the flow of the hot water outlet flow path 40 can be stopped by closing the water stop mechanism 45 when replacing a home's mixer faucet. This has the advantage of eliminating the need to drain a certain amount of hot water from the hot water storage tank 10 in advance.

2 is a cross-sectional view showing the structure of the hot water outlet 42 of the storage-type hot water heater 1 in embodiment 1. FIG. 3 is an enlarged cross-sectional view of a portion of FIG. 2. FIG. 4 is a perspective view showing the structure of the hot water outlet 42 of the storage-type hot water heater 1 in embodiment 1. As shown in these figures, the water stop mechanism 45 of the hot water outlet 42 in this embodiment is composed of a butterfly valve. As shown in FIG. 2, the water stop mechanism 45 has a flat plate 60 that can rotate between a closed position and an open position, and is structured to stop water flow by opening and closing the flat plate 60. The flat plate 60 corresponds to the disk of a butterfly valve. In this embodiment, by configuring the water stop mechanism 45 with a butterfly valve that has the characteristic of little flow rate reduction, it is possible to reliably prevent a decrease in the hot water supply flow rate to the external hot water supply piping 41. As shown in FIG. 4, the operating lever 70 for operating the water stop mechanism 45 is configured to rotate integrally with the flat plate 60.

Let's assume that the hot water supply outlet 42 does not have a stop valve 45, and a stop valve is installed somewhere along the external hot water supply piping 41. In this case, the contractor installing the storage-type hot water heater 1 will prepare the stop valve and install it somewhere along the external hot water supply piping 41. In this case, the stop valve prepared by each contractor will vary, so if, for example, a stop valve with a diameter significantly smaller than that of the external hot water supply piping 41 is used, the desired hot water supply flow rate cannot be ensured. This could result in complaints about the hot water heater. In contrast, in this embodiment, by installing the stop valve 45 in the hot water supply outlet 42, it is possible to consider a structure that incorporates the stop mechanism 45. This can reliably prevent complaints due to reduced hot water supply flow rate, etc.

As shown in Figure 2, when the flat plate 60 is parallel to the flow path inside the hot water inlet 42, the water stop mechanism 45 is in an open state, allowing water to pass through. In contrast, when the flat plate 60 is perpendicular to the flow path inside the hot water inlet 42, the water stop mechanism 45 is in a closed state, preventing water from passing through. When water is passing through, the flat plate 60 allows water to pass through without significantly affecting the flow rate. Furthermore, the size of the hot water inlet 42 can be made almost the same as when the water stop mechanism 45 is not installed, and there is little impact during installation.

The thinner the flat plate 60, the better, and it is desirable to keep the surface area that comes into contact with the water as small as possible.

As a variant, the water stop mechanism 45 may be configured using a ball valve instead of a butterfly valve. Figure 5 is a cross-sectional view showing an example of a hot water outlet 42 having a water stop mechanism 45 configured using a ball valve. The water stop mechanism 45 shown in Figure 5 has a ball valve body 46. The ball valve body 46 is connected to an operating lever 70 via a rotating shaft 47. Figure 5 shows a state in which water can pass through the hole formed in the ball valve body 46, i.e., the ball valve is in the "open" position. It is desirable that the flow path cross-sectional area of the hole formed in the ball valve body 46 be equal to or greater than the flow path cross-sectional area of the hot water outlet flow path 40. Doing so makes it possible to more reliably reduce pressure loss in the ball valve and more reliably prevent any impact on the hot water supply flow rate.

If a different valve body, such as a gate valve or other water stop mechanism 45, is used, it is possible to ensure the same diameter as the hot water outlet flow path 40 or the external hot water supply pipe 41, but the external dimensions will be significantly larger, which will have various disadvantages, such as interference when connecting external pipes such as the external hot water supply pipe 41 to the storage-type hot water heater 1, making it impossible to wrap insulation material around it when performing insulation work, and increasing the weight due to the larger structure.

As shown in Figure 3, when the butterfly valve is closed, the edge 61 of the flat plate 60 comes into contact with the inner wall of the passage of the hot water outlet 42 in which the flat plate 60 is housed, thereby achieving a water-stopping function.

The inner surface of the hot water outlet 42 has an R-shape where it comes into contact with the flat plate 60. The flat plate 60 also has an R-shape at the position where it comes into contact with the inner surface of the hot water outlet 42. The contact between the R-shapes provides a water-stopping function.

The R-shape depends on the shape of the contact between the flat plate 60 and the inner surface of the hot water inlet 42, and differs depending on whether two convex shapes are in contact with each other or whether two concave shapes are in contact with each other.

The cross-sectional view in the upper right corner of Figure 3 shows an example of contact between convex surfaces. In this example, the edge 61 of the flat plate 60 has a convex curved shape, i.e., an R-shape, that exhibits a convex curve in a cross section cut along a plane perpendicular to the flat plate 60. The inner surface of the passage of the hot water outlet 42 that houses the flat plate 60 is provided with a contact portion 62 that comes into contact with the edge 61 of the flat plate 60 when the butterfly valve is closed. This contact portion 62 has a convex curved shape, i.e., an R-shape, that exhibits a convex curve in a cross section cut along a plane including the center line of the passage of the hot water outlet 42. Regarding contact between such convex surfaces, there is no set rule regarding the magnitude relationship between the R-shape dimensions of the inner surface of the hot water outlet 42 and the R-shape dimensions of the flat plate 60; as long as there is an R-shape, line contact is possible, ensuring sealing performance.

The cross-sectional view at the bottom right of Figure 3 shows an example of contact between a concave surface and a convex surface. In this example, the edge 61 of the flat plate 60 has a convex curved surface, i.e., an R-shape, that exhibits a convex curve in a cross section cut along a plane perpendicular to the flat plate 60. The radius of curvature of this convex curve is RA. The inner surface of the passage of the hot water outlet 42 that houses the flat plate 60 has a contact portion 63 that comes into contact with the edge 61 of the flat plate 60 when the butterfly valve is closed. This contact portion 63 has a concave curved surface that exhibits a concave curve in a cross section cut along a plane including the center line of the passage of the hot water outlet 42. The radius of curvature RB of the concave curve of the contact portion 63 is greater than the radius of curvature RA of the convex curve of the edge 61 of the flat plate 60. If RA = RB, the entire contact surface would be watertight. However, if a tolerance is set, RB may be less than RA, which may result in insufficient watertightness. In contrast, by making RB > RA, it is possible to create a structure that ensures line contact, resulting in a structure that reliably performs its waterproofing function.

In this embodiment, the R-shaped line-contact seal structure ensures the necessary sealing to prevent excessive hot water discharge, which is necessary when replacing a home faucet mixer, with a simple configuration. This eliminates the need to form a rubber gasket or seal on the disk or hot water outlet 42 side, as is the case with conventional butterfly valves, and more reliably prevents an increase in pressure loss in the flow path.

Here, it is desirable that the water stop mechanism 45 be in the "open" state when the hot water storage type water heater 1 is shipped from the factory. In other words, the shipping method for the hot water storage type water heater 1 according to this embodiment involves shipping the hot water storage type water heater 1 with the water stop mechanism 45 in the open state when it is shipped from the factory.

Unlike conventional methods, contractors installing the storage-type water heater 1 no longer need to install a stop valve somewhere on the external hot water supply piping 41. This means that contractors may become less careful about the water stop mechanism 45. In contrast, by leaving the water stop mechanism 45 in the "open" position as the factory default, contractors no longer need to set the water stop mechanism 45 built into the storage-type water heater 1 to the "open" position each time they install the unit. This eliminates the need for the water stop mechanism 45 to be accidentally closed, which can increase pressure loss and reduce the amount of hot water supplied, and also prevents contractors from accidentally operating the water stop mechanism 45 to the "closed" position.

As shown in Figures 4 and 5, the water stop mechanism 45 has a structure that allows it to be opened and closed using an operating lever 70. By allowing the water stop mechanism 45 to be opened and closed using the operating lever 70, it is possible to avoid having to reach in and perform an unnatural operation when external piping is installed, making it easy for contractors or users to operate by hand.

The operating lever 70 is formed in a straight line. When the water stop mechanism 45 is open, the longitudinal direction of the operating lever 70 is substantially parallel to the central axis of the hot water outlet 42. When the water stop mechanism 45 is closed, the longitudinal direction of the operating lever 70 is substantially perpendicular to the central axis of the hot water outlet 42. In this way, it is desirable to configure the water stop mechanism 45 so that when the operating lever 70 is parallel to the water flow direction of the hot water outlet 42, the water stop mechanism 45 is in the "open" state, and when the operating lever 70 is perpendicular to the water flow direction of the hot water outlet 42, the water stop mechanism 45 is in the "closed" state.

Unlike conventional methods, contractors installing the storage-type water heater 1 no longer need to install a stop valve somewhere on the external hot water supply piping 41. This means that contractors may become less attentive to the water stop mechanism 45. As such, there is a risk that contractors will have a lower level of understanding of the open/closed state of the water stop mechanism 45 built into the storage-type water heater 1. In contrast, with this configuration, contractors can easily recognize which state is "open" even without special knowledge. This prevents contractors from accidentally operating the water stop mechanism 45 and setting it to the "closed" state.

Furthermore, if there is an easy-to-operate method other than the operating lever 70, the operating lever 70 is not limited to this, and a different method may be used that prioritizes operability.

The above configuration ensures that the specified hot water supply performance is achieved without being affected by installation, and also allows for efficient replacement of in-home mixer faucets.

1. Storage-type water heater, 2. Outer case, 3. Tank piping, 10. Storage tank, 20. Water supply piping, 21. External water supply piping, 22. Water supply port, 30. Mixing valve, 40. Hot water outlet flow path, 41. External hot water supply piping, 42. Hot water supply port, 45. Water stop mechanism, 46. Ball valve body, 47. Rotating shaft, 60. Flat plate, 61. Edge, 62. Contact portion, 63. Contact portion, 70. Operating lever

Claims (6)

A hot water tank and
an exterior case that houses the hot water storage tank;
a water supply port that is disposed so that one end thereof is exposed to the outside of the outer case and that is connectable to an external water supply pipe;
a water supply pipe that connects the water supply port and the hot water storage tank and sends water supplied from the external water supply pipe into the hot water storage tank;
a mixing valve that mixes hot water from the hot water storage tank and water from the water supply pipe;
a hot water supply port that is disposed so that one end thereof is exposed to the outside of the outer case and that is connectable to an external hot water supply pipe;
a hot water outlet flow path that sends hot water from the mixing valve to the hot water outlet;
a water stop mechanism provided in the hot water supply port and capable of stopping the flow of the hot water outlet flow path;
Equipped with
the hot water supply port is disposed in a riser portion of the outer case,
The water stop mechanism is composed of a ball valve or a butterfly valve,
A storage-type water heater in which the hot water that passes through the external hot water supply pipe is sent to a mixing faucet inside the house. The water stop mechanism is composed of a butterfly valve,
The edge of the disk of the butterfly valve has a convex curved surface shape that exhibits a convex curve in a cross section cut along a plane perpendicular to the disk,
a contact portion that comes into contact with the edge of the disk when the butterfly valve is closed, on an inner surface of the passage that houses the disk;
The hot water storage type water heater according to claim 1, wherein the contact portion has a convex curved surface shape that exhibits a convex curve in a cross section cut along a plane including a center line of the passage. The water stop mechanism is composed of a butterfly valve,
The edge of the disk of the butterfly valve has a convex curved surface shape that exhibits a convex curve in a cross section cut along a plane perpendicular to the disk,
a contact portion that comes into contact with the edge of the disk when the butterfly valve is closed, on an inner surface of the passage that houses the disk;
the contact portion has a concave curved surface shape that exhibits a concave curve in a cross section cut along a plane including a center line of the passage,
2. The hot water storage type water heater according to claim 1, wherein the radius of curvature of the concave curve is larger than the radius of curvature of the convex curve. The water shutoff mechanism is composed of a ball valve having a ball valve body,
2. The hot water storage type water heater according to claim 1, wherein a flow passage cross-sectional area of the hole formed in the ball valve body is equal to or larger than a flow passage cross-sectional area of the hot water outlet flow passage. Further provided is an operating lever for operating the water stop mechanism,
When the water shutoff mechanism is open, the operating lever is substantially parallel to the central axis of the hot water outlet,
5. The hot water storage type water heater according to claim 1, wherein the operating lever is substantially perpendicular to the central axis of the hot water outlet when the water stop mechanism is closed. A shipping method for a storage type water heater according to any one of claims 1 to 5, in which the water shutoff mechanism is shipped in an open state when the storage type water heater is shipped from a factory.