JP2008249069A - High temperature discharge preventing valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high temperature discharge preventing valve for avoiding the discharge of mixed water (high temperature hot water) over a predetermined temperature range from a discharge port even when a valve element or a valve seat is broken. <P>SOLUTION: The high temperature discharge preventing valve 1 comprises an adjusting screw 50 having a collar portion 52 in contact with the end of an adjusting spring 40, and the valve element 10 having a cylindrical valve element portion 11, a ring-shaped supporting ring portion 12 located under the valve element portion and abutting on one end of the actuator 30, and a rib 13 connecting the valve element portion 11 to the supporting ring portion 12, wherein the mechanical strength of the collar portion 52 of the adjusting screw 50 is smaller than the mechanical strength of the rib 13 of the valve element 10. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high-temperature hot water prevention valve having a mixing function for mixing hot water and water, for example, installed on the discharge side of a water heater such as an electric water heater or a water heater, in particular, a temperature sensitive member made of a shape memory alloy. It relates to a high temperature hot water prevention valve that is used.

Electric water heaters and hot water storage hot water heaters use a high temperature hot water prevention valve having a mixing function that mixes hot water and water of about 60 ° C. to 80 ° C. to generate hot water of about 40 ° C., for example. .
This high-temperature hot water prevention valve is installed on the discharge side of electric water heaters and hot water storage-type water heaters, has a built-in mixing valve function for discharging hot water stored at an appropriate temperature, and this mixing valve function fails. However, by always taking water into the valve from the water supply port and diluting the hot water, the temperature of the mixed water discharged from the mixed water outlet is set to a safe temperature that does not cause burns.

  As this high temperature hot water prevention valve, for example, the one shown in JP-A-2006-46527 is known. A high temperature hot water prevention valve disclosed in Japanese Patent Application Laid-Open No. 2006-46527 will be described with reference to FIGS.

  As shown in FIG. 9, the housing 101 of the high temperature hot water prevention 100 includes a hot water supply port 102 for supplying hot water of about 60 ° C. to 80 ° C. from a hot water storage unit (not shown), and a water supply port for supplying water from the water supply. 103 and a discharge port 104 that mixes hot water supplied from the hot water supply port 102 and water supplied from the water supply port 103 and discharges hot water having an appropriate temperature of about 40 ° C.

  Further, inside the housing 101, a valve body 110 and a valve seat 120 in which the hot water passage A is narrowed when the valve body 110 approaches and the hot water passage A is expanded when the valve body 110 is separated are provided. . In addition, an actuator 130 for mixing the hot water from the hot water supply port 102 and the water from the water supply port 103 and sensing the temperature of the mixed hot water to move the valve body 110 forward and backward is provided.

  Further, an adjustment spring 140 that adjusts the temperature of hot water discharged from the discharge port is provided between the valve body 110 and the adjustment screw 150 attached to the valve seat 120. The adjustment screw 150 has a function of adjusting the temperature of hot water discharged from the discharge port 104 by screwing into the valve seat 120 and changing the length of the adjustment spring 140.

More specifically, the valve seat 120 has a cylindrical main body 121 and a larger diameter than the main body 121 connected to the tip of the main body 121 via a rib 121a as shown in FIG. A cylindrical fixing portion 122 is formed.
A screw part 121 b is formed on the inner side surface of the main body 121, and is formed so as to be screwed with a screw part 150 a formed on the outer side surface of the adjustment screw 150. A screw portion 122 a is formed on the outer peripheral surface of the fixing portion 122, and is configured to be screwed into a screw portion (not shown) formed in the housing 101 so that the valve seat 120 can be fixed to the housing 101. Yes.

Further, as shown in FIG. 11, the valve body 110 includes a cylindrical valve body portion 111, a ring-shaped support ring portion 112 that is positioned below the valve body portion 111, and is in contact with the upper end of the actuator 130, A shaft portion 113 that connects the valve body portion 111 and the support ring portion 112 is provided. The tip of the valve body 111 is housed inside the fixed part 122 of the valve seat 120 as indicated by the phantom line in FIG. 9, and the tip of the valve body 111 is the main body 121 of the valve seat 120. By approaching the lower surface (see the solid line in FIG. 9), the hot water flow path A is narrowed, and the tip of the valve body 111 is separated from the lower surface of the main body 120 of the valve seat 120 (see the phantom line in FIG. 9). The path A is configured to expand.
The main body 111 and the shaft 113 and the support ring 112 and the shaft 113 are connected by ribs 111a and 112a, and a hot water flow path A is formed inside the main body 11 and inside the support ring 112. ing.

  Further, as shown in FIG. 9, an adjustment spring 140 is installed so as to contact the lower surface of the adjustment screw 150 and to contact the upper surface of the rib 111 a of the valve body 110. The length of the adjustment spring 140 can be changed by rotating the adjustment screw 150.

  Further, the actuator 130 is installed in contact with the lower surface of the support ring 112 and the upper surface of the rib 101 a provided on the discharge port 104 side of the housing 101. The actuator 130 is a temperature sensitive member, specifically a shape memory alloy spring. In FIG. 9, reference numeral 160 denotes an O-ring.

Next, operation | movement of the high temperature hot-water prevention valve 100 comprised in this way is demonstrated based on FIG.
First, when the temperature of hot water discharged from the discharge port 104 is low, the actuator 130 that is a temperature-sensitive member is contracted, and the repulsive force of the adjustment spring 140 causes the tip of the main body 111 of the valve body 110 to move. The hot water flow path A is expanded and brought into a state as shown by the phantom line in FIG. Accordingly, since hot water from the hot water supply port 102 flows in, the temperature of the mixed water discharged from the outlet side increases.

  On the other hand, when the temperature of the mixed water discharged from the discharge port 104 exceeds a predetermined temperature, the actuator 130 is extended against the repulsive force of the adjustment spring 140, and the tip of the valve body 111 of the valve body 110 is extended. The hot water passage A is narrowed by approaching the lower surface of the main body 121 of the valve seat 120. As a result, hot water from the hot water supply port 102 decreases, and the temperature of the mixed water discharged from the discharge port 104 decreases.

Thus, since the actuator 130 as the temperature sensitive member is provided in the discharge area D that is downstream of the mixing area C where the hot water flow path A and the water supply flow path B intersect, hot water discharged from the discharge port is provided. The temperature can be adjusted to an appropriate temperature. Moreover, since water (tap water) is always supplied from the water supply port 103, the temperature of the mixed water discharged from the mixed water outlet can be set to a safe temperature that does not cause burns.
JP 2000-283329 A

By the way, when used for many years, it is predicted that thermal stress repeatedly acts on the valve body 110 and the valve seat 120 and is damaged. Further, it is predicted that the internal pressure of the housing 101 will rise abnormally and the valve body 110 and the valve seat 120 will be damaged.
A case where the valve body 110 and the valve seat 120 are damaged will be described with reference to FIGS. 9 and 12 as an example of a case where the rib 112a connecting the support ring 112 and the shaft portion 113 of the valve body 110 is damaged.
First, as shown in FIG. 9, when the rib 112a is not damaged, if the temperature of the hot water in the mixing zone D exceeds a predetermined temperature, the actuator 130 extends against the repulsive force of the adjusting spring 140, and the valve The distal end portion of the main body 111 of the body 110 approaches the lower surface of the main body 121 of the valve seat 120, and the hot water flow path A is narrowed.

However, as shown in FIG. 12, when the rib 112a is damaged, the temperature of the hot water in the mixing zone D exceeds the predetermined temperature is detected by the actuator 130, which is a temperature-sensitive member. Is damaged and the support ring 112 is in a free state, so that the front end portion of the valve body portion 111 of the valve body 110 is opposed to the lower surface of the main body portion 121 of the valve seat 120 against the repulsive force of the adjustment spring 140. The hot water flow path A cannot be narrowed.
Furthermore, since only the repulsive force of the adjustment spring 140 acts on the valve body 110, the valve body 110 is further separated from the valve seat 120, and the hot water flow path A is opened to the maximum. As a result, the amount of hot water from the hot water supply port 102 increases, and higher temperature mixed water is discharged from the discharge port 104.

  Furthermore, there is a possibility that the broken support ring 112 may block the outlet of the water supply port 103. In this case as well, the amount of water supplied from the water supply port 103 decreases, so that higher temperature mixed water is discharged from the discharge port 104.

  As described above, when the valve body 110 and the valve seat 120 are damaged, hot water exceeding a predetermined temperature range is discharged from the discharge port, and there is a concern that the user's body may be injured such as a burn.

  The present invention has been made to solve the above technical problem, and even when the valve body and the valve seat are damaged, mixed water (hot water) exceeding a predetermined temperature range is discharged from the discharge port. An object of the present invention is to provide a high temperature hot water prevention valve that is free from heat.

  A high temperature hot water prevention valve according to the present invention includes a housing provided with a hot water supply port, a water supply port and a discharge port, a valve body formed so as to be capable of advancing and retracting inside the housing, and the valve body approaching from the hot water supply port. A valve seat whose hot water flow path narrows when the hot water flow path narrows and the hot water flow path expands is mixed with hot water from the hot water supply port and water from the water supply port, and the valve body is sensed by detecting the temperature of the mixed hot water. An adjustment spring that adjusts the temperature of hot water discharged from a discharge port, one end of which is in contact with the valve body, and a length of the adjustment spring by screwing into the valve seat and changing the screwing position. A high-temperature hot water prevention valve having an adjusting screw for changing the height, wherein the adjusting screw is provided below a head portion on which a screw portion is formed to be screwed with a screw portion of the valve seat, and below the head portion. And a flange that contacts the other end of the adjustment spring, The valve body connects a cylindrical valve body portion, a ring-shaped support ring portion that is positioned below the valve body portion and abuts against one end of the actuator, and the valve body portion and the support ring portion. And a rib, and the mechanical strength of the flange portion of the adjusting screw is smaller than the mechanical strength of the rib of the valve body.

  As described above, the mechanical strength of the flange portion of the adjusting screw is made smaller than the mechanical strength of the rib of the valve body, so that an abnormal load from the adjusting screw and the actuator and a load due to an abnormal internal pressure inside the housing are obtained. In addition, when aging occurs, the buttock is first damaged. When the collar part is damaged, the adjusting spring pushes and extends the collar part, and the repulsive force of the adjusting spring weakens, so that the balance with the repulsive force of the actuator is lost, the actuator extends, and the valve body is pushed up. . As a result, the amount of hot water from the hot water supply port decreases, the temperature of the hot water discharged from the discharge port decreases, and accidents such as user burns are avoided.

  Here, the flange portion of the adjusting screw is formed in the radial direction, and is configured to receive a repulsive force from the adjusting spring and the actuator as a shearing force, and the rib of the valve body is in the axial direction of the cylindrical valve body portion It is desirable that the bottom surface of the valve body portion and the top surface of the support ring portion are connected to each other so that the repulsive force from the adjustment spring and the actuator is received as a compression force.

  Further, it is desirable that a protrusion means is provided in contact with or close to the upper end surface of the valve seat, and the valve seat is held by the protrusion means. Since the valve seat is held by the protrusion means in this way, it is possible to prevent the valve seat from falling off, and even if the valve seat is broken, there is no increase in the amount of hot water from the hot water inlet, and there is an accident such as a burn of the user. Can be avoided.

  The protrusion means is a protrusion provided on a connecting pipe connected to the hot water supply port, or a protrusion provided on a ring-shaped plate member installed on the hot water supply port in contact with the connection pipe connected to the hot water supply port. Part is desirable.

Further, it is desirable that the other end portion of the actuator is locked to a rib formed on the housing, and the rib is held by holding means.
Since the rib is held by the holding means in this way, the actuator can be prevented from falling off even if the rib is broken, and there is no increase in the amount of hot water from the hot water supply port, thereby avoiding an accident such as a burn of the user. Can do. The holding means is preferably an end face of a connecting pipe connected to the hot water supply port.

  ADVANTAGE OF THE INVENTION According to this invention, even if a valve body and a valve seat are damaged, the high temperature hot-water prevention valve which does not discharge the mixed water (high temperature hot water) exceeding a predetermined temperature range from a discharge outlet can be obtained.

  An embodiment of the present invention will be described with reference to FIGS. 1 is a sectional view showing an embodiment of the high temperature hot water prevention valve according to the present invention, FIG. 2 is an exploded perspective view of the embodiment shown in FIG. 1, and FIG. 3 is a valve seat shown in FIG. (A) is a plan view, (b) is a side view, (c) is a sectional view, and FIG. 4 is a diagram showing the valve body shown in FIG. FIG. 5 (b) is a bottom view, FIG. 5 (c) is a perspective view, FIG. 5 is a view showing the adjusting screw shown in FIG. 1, wherein FIG. 5 (a) is a plan view, FIG. FIG. 7 is a cross-sectional view showing a state where the hot water passage is opened, and FIG. 7 is a view showing a state where the adjusting screw shown in FIG. 1 is broken.

As shown in FIG. 1, the housing 2 of the high temperature hot water prevention valve 1 is formed with a hot water supply port 3 to which a connection pipe 60 having one end connected to a hot water storage unit (not shown) is connected. The connecting pipe 60 supplies hot water of about 60 ° C. to 80 ° C. from the hot water storage section into the housing 2.
The housing 2 is mixed with a water supply port 4 to which water from a water supply is supplied, hot water supplied from the hot water supply port 3 and water supplied from the water supply port 4, and hot water having an appropriate temperature of about 40 ° C. And a discharge port 5 for discharging water. One end of a connection pipe 70 connected to the faucet is connected to the discharge port 5.

Inside the housing 101, there is provided a valve body 10 and a valve seat 20 in which the hot water passage A is narrowed when the valve body 10 approaches and the hot water passage A is expanded when the valve body 10 is separated. Also, an actuator 30 is provided for mixing the hot water from the hot water supply port 3 and the water from the water supply port 4 and sensing the temperature of the mixed hot water to move the valve body 10 forward and backward. The actuator 30 is a temperature sensitive member, specifically a shape memory alloy spring.
One end of the actuator 30 is in contact with the lower surface of the valve body 10, and the other end is in contact with the upper surface of the rib 5 a provided on the discharge port 5 side of the housing 2.

Further, an adjustment spring 40 for adjusting the temperature of hot water discharged from the discharge port is installed between the valve body 10 and the adjustment screw 50 attached to the valve seat 20. The length of the adjustment spring 40 can be changed by rotating the adjustment screw 50 screwed into the valve seat 20.
Note that reference numeral 6 in the figure denotes an O-ring.

  As described above, the high-temperature hot water prevention valve according to the present invention includes the same components as those of the conventional high-temperature hot water prevention valve, but is different from the conventional high-temperature hot water prevention valve in the components. have.

First, the valve seat 20 will be described. The valve seat 20 includes a cylindrical main body portion 21 and a cylindrical fixing portion 22 having a diameter larger than that of the main body portion 21 as shown in FIGS. I have.
The fixing portion 22 is connected to the distal end portion of the main body portion 21 via a rib 21a formed in the axial direction. Further, the fixing portion 22 is connected via a rib 22 a formed in the radial direction of the fixing portion 22.
Thus, since the main-body part 21 and the fixing | fixed part 22 are connected by the rib 21a formed in the axial direction, and the rib 22a formed in radial direction, both can be connected firmly and damage can be prevented.

  Further, a screw portion 21 b is formed on the inner side surface of the main body portion 21, and is formed so as to be screwed with a screw portion 51 a formed on the outer surface of the adjustment screw 50. Further, a screw portion 22b is formed on the outer peripheral surface of the fixing portion 22, and is configured to be screwed into a screw portion (not shown) formed in the housing 2 so that the valve seat 20 can be fixed to the housing 2. Yes.

  Next, the valve body 10 will be described with reference to FIGS. As shown in FIG. 4, the valve body 10 includes a cylindrical valve body portion 11, a ring-shaped support ring portion 12 that is positioned below the valve body portion 11, and contacts the upper end of the actuator 30, A rib 13 is provided to connect the valve body portion 11 and the support ring portion 12.

The rib 13 is formed in the axial direction of the cylindrical valve body part 11 and connects the bottom surface of the valve body part 11 and the upper surface of the support ring part 12.
Thus, since the rib 13 is formed in parallel to the axis of the cylindrical valve body 11, the rib 13 receives a compressive load from the actuator 30 and the adjustment spring 40.
In the case of a plate-like member such as the rib 13, in the case of the same size and shape, the mechanical strength is greater with respect to the compressive load than the shear load. Therefore, when the rib 13 is formed parallel to the axis of the cylindrical valve body 11 so as to receive a compressive load, the support ring 112 and the shaft 113 are radially arranged like the conventional valve body 110. Compared with the case where it connects with the extending rib 112a, mechanical strength can be enlarged.

Further, as shown in FIG. 1, the tip of the valve body 11 is accommodated inside the fixed portion 22 of the valve seat 20, and the valve body 10 advances so that the tip of the valve body 11 is the valve seat. The hot water flow path A is narrowed by approaching the lower surface of the main body portion 21 of the 20, and the hot water flow path A is formed by retreating the valve body 10 and separating the tip of the valve body 11 from the lower surface of the main body portion 21 of the valve seat 20. It is configured to spread.
1, the hot water passage A passes between the main body 21 and the fixed portion 22 from the outside of the main body 21 of the valve seat 20, and as shown by an arrow in FIG. It is formed inside the ring 12.

Further, the adjusting screw 50 will be described with reference to FIGS. On the outer peripheral surface of the head 51 of the adjusting screw 50, a screw part 51a that is screwed with the screw part 21b of the valve seat 20 is formed. Further, the head 51 is formed with a hexagonal hole 51b, and the adjusting screw 50 can be rotated by fitting and rotating the tool with the hexagonal hole 51b.
In addition, the screw part 22b formed in the fixing | fixed part 22 of the valve seat 20 and the said screw part 21b form the screw of the reverse direction. This prevents the valve seat 20 from falling off the housing 2 when the adjusting screw 50 is screwed into the valve seat 20.

Also, below the head 51 is provided a flange 52 extending radially outward with respect to the axis. The upper end portion of the adjustment spring 40 is in contact with the lower surface of the flange portion 52, and the lower end portion of the adjustment spring 40 is in contact with the upper surface of the rib 13 of the valve body 10. The flange 52 is separate from the adjusting screw 50 and may be integrated with the adjusting screw 50 by fitting or screwing.
Further, by rotating the adjusting screw 50, the adjusting spring 50 can be moved forward and backward with respect to the main body 21 of the valve seat 20, and the length of the adjusting spring 40 can be changed. By changing the length of the adjustment spring 40 in this way, the repulsive force of the adjustment spring 40 can be changed.

The flange portion 52 extends in the radial direction as described above, and is configured to receive the repulsive force from the adjustment spring 40 and the actuator 30 as a shearing force, and further, the main body portion 21 and the fixing portion of the valve seat 20 described above. The mechanical strength of the rib 21 a and the rib 22 a connecting the two 22 and the rib 13 of the valve body 10 is weaker.
That is, the flange portion 52 is formed so as to be a portion having the weakest mechanical strength among the members to which the repulsive force from the adjustment spring 40 and the actuator 30 acts as described above. It is formed as the most easily damaged part.

Further, the connecting pipe 60 will be described with reference to FIG.
A projecting portion 61 extending in the radial direction is formed at the end of the connecting tube 60, and the connecting tube 60 is attached to the housing 2 so that the lower surface of the projecting portion 61 is in contact with the upper end surface of the valve seat 20.
The hot water passage A is formed outside the main body 21 of the valve seat 20 through the connecting pipe 60 and between the protrusions 61.

As described above, since the protrusion 61 is in contact with the upper end surface of the main body 21 of the valve seat 20, it is possible to prevent the valve seat 20 from falling off the housing 2.
The protrusion 61 is preferably extended to the inside of the screw portion 21b of the valve seat 21. Thus, when the projection 20 extends to the inside of the screw portion 21 b of the valve seat 21, it is possible to prevent the adjustment screw 50 from falling off the valve seat 21. The protrusion 61 does not necessarily need to be in contact with the upper end surface of the main body 21 of the valve seat 20 and may be provided close to the valve seat 20 to prevent the valve seat 20 from dropping off.

  Furthermore, the connection pipe 70 will be described with reference to FIG. A through hole 70 a is formed at the center of the end of the connection pipe 50. The upper end surface of the connection pipe 70 is attached so as to be in contact with the lower end surface of the rib 2 a of the housing 2. Thus, since the upper end surface of the connecting pipe 70 is in contact with and held by the rib 2a of the housing 2, even if the rib 2a of the housing 2 to which the end of the actuator 30 is locked is broken, the actuator 30 is dropped. Is prevented.

Next, operation | movement of the high temperature hot-water prevention valve 1 comprised in this way is demonstrated based on FIG.
First, when the temperature of hot water discharged from the discharge port 5 (connecting pipe 70) is low, the actuator 30 that is a temperature sensitive member is contracted, and the repulsive force of the adjustment spring 40 causes the main body portion of the valve body 10 to contract. 11 is retracted from the lower surface side of the main body 21 of the valve seat 20, and the hot water flow path A is expanded as shown in FIG. Therefore, since hot water from the hot water supply port 3 (connection pipe 60) flows in, the temperature of the mixed water from the discharge port 5 (connection pipe 70) increases.

  On the other hand, when the temperature of the hot water discharged from the discharge port 5 (connection pipe 70) exceeds a predetermined temperature, the actuator 30 extends against the repulsive force of the adjustment spring 40, and the valve body portion 11 of the valve body 10 extends. The front end portion approaches the lower surface of the main body portion 21 of the valve seat 20, and the hot water flow path A is narrowed. As a result, hot water from the hot water supply port 3 (connection pipe 60) decreases, and the temperature of the mixed water from the discharge port 5 (connection pipe 70) decreases.

  Thus, since the actuator 130 which is the temperature sensing member is provided in the discharge area D which is downstream of the mixing area C where the hot water flow path A and the water supply flow path B intersect, it is discharged from the discharge port 5. The temperature of the hot water can be adjusted to an appropriate temperature.

Next, a case where an abnormal load from the adjusting screw 40 and the actuator 30 or aged deterioration occurs and a component is damaged will be described.
Loads from the adjusting screw 40 and the actuator 30 act on the flange portion 52 of the adjusting screw 50, the rib portion 13 of the valve body 10, the rib 2a of the housing 2, and the screwed portion between the adjusting screw 50 and the valve seat 20. It acts on the rib portions 21a and 22a of the valve seat 20.

  Here, even if the rib 2a of the housing 2 is damaged due to an abnormal load from the adjusting screw 40 or the actuator 30, or due to aging, the upper end surface of the connecting pipe 70 is in contact, so that the actuator 30 is prevented from falling off. Is done. Accordingly, hot water is not discharged from the discharge port 5 (connection pipe 70).

Even if the screwed portion between the adjusting screw 50 and the valve seat 20 is broken, the upper end surface of the head 51 of the adjusting screw 50 comes into contact with the protruding portion 61 of the connecting pipe 60, so that the drop-out is prevented.
Here, when the adjusting screw 50 comes off the valve seat 20 and comes into contact with the protruding portion 61, the adjusting screw 50 is shifted from the screwing position to the protruding portion side (upward). However, the adjustment spring 40 is extended along with this, and the repulsive force of the adjustment spring 40 is weakened. As a result, the balance between the repulsive force of the adjustment spring 40 and the repulsive force of the actuator 30 is lost, and the actuator 30 extends.
That is, the actuator 30 pushes up the valve body 10, and the tip of the valve body portion 11 of the valve body 10 abuts on the valve seat 20, so that the hot water flow path A is narrowed or completely closed. Is reduced or blocked. As a result, the temperature of the hot water discharged from the discharge port 5 (connection pipe 70) can be lowered, and an accident such as a burn of the user can be avoided.

  Even if the rib portions 21a and 22a of the valve seat 20 are damaged, the upper surface of the main body portion 21 of the valve seat 20 abuts on the projection 61 of the connecting pipe 60, and the adjustment spring 40 and the actuator 30 are repelled from below. Since the force acts, the normal mounting state can be maintained. As a result, since the amount of hot water from the hot water supply port 3 does not increase, accidents such as burns of the user can be avoided.

Further, the adjusting screw 50 is provided with the flange portion 52 as described above, and is formed with a mechanical strength smaller than that of the rib 13 of the valve body 10. Therefore, when an abnormal load from the adjusting screw 40 or the actuator 30 or aged deterioration occurs, the flange portion 52 is first damaged than the rib portion 13 of the valve body 10.
The flange 52 of the adjusting screw 50 is connected to any of the rib portion 13 of the valve body 10, the rib 2 a of the housing 2, the screwed portion between the adjusting screw 50 and the valve seat 20, and the rib portions 21 a and 22 a of the valve seat 20. However, it is preferable to form it with weak mechanical strength.

Next, a case where the collar portion 52 is damaged due to an abnormal load from the adjusting screw 40 and the actuator 30, a load due to an abnormal internal pressure in the housing 2, or aged deterioration will be described.
In the state shown in FIG. 6 where hot water of an appropriate temperature is discharged from the discharge port 5 (connection pipe 70), when the collar part 52 is damaged, the adjustment spring 40 pushes up the collar part 52 and extends as shown in FIG. . As a result, the repulsive force of the adjustment spring 40 becomes weak, the balance with the repulsive force of the actuator 30 is lost, and the actuator 30 extends.

  That is, the actuator 30 pushes up the valve body 10, the tip of the valve body portion 11 comes into contact with the valve seat 20 and closes the hot water passage A, so that hot water from the hot water supply port 3 (connection pipe 60) is blocked. . As a result, the temperature of the hot water discharged from the discharge port 5 (connection pipe 70) can be lowered, and an accident such as a burn of the user can be avoided.

  FIG. 7 shows a state in which the valve body 10 is in contact with the valve seat 20 and the hot water flow path A is blocked, but the actuator 30 pushes up the valve body 10 and makes contact with the valve seat 20. Instead, the hot water channel A may be narrowed. Thus, even when the hot water flow path A is narrowed, the hot water from the hot water supply port 3 (connection pipe 60) decreases, and the temperature of the hot water discharged from the discharge port 5 (connection pipe 70) can be lowered. And accidents such as user burns can be avoided.

  As described above, whether the hot water flow path A is completely blocked or narrowed to a constant hot water flow path A when the flange 52 is damaged depends on the spring constant, length of the adjustment spring 40 and the actuator 30. This can be performed by appropriately selecting the thickness of the flange 51, the distance between the flange 51 and the lower surface of the head 51 of the adjusting screw 50, and the like.

  Moreover, in the said embodiment, although the projection part 61 was formed in the end surface of the connection pipe 60, the said projection part 61 is good also as another member. That is, as shown in FIG. 8, a protrusion 81 may be formed on the lower surface of a ring-shaped plate member 80 and used in combination with a connecting pipe 60 of a cylindrical pipe.

  The high temperature hot water prevention valve according to the present invention is suitably used for a water heater such as an electric water heater, a water heater and the like.

It is sectional drawing which shows one Embodiment concerning the high temperature hot-water prevention valve of this invention. It is a disassembled perspective view of one Embodiment shown in FIG. It is a figure which shows the valve seat shown in FIG. 1, Comprising: (a) is a top view, (b) is a side view, (c) is sectional drawing. It is a figure which shows the valve body shown in FIG. 1, Comprising: (a) is sectional drawing, (b) is a bottom view, (c) is a perspective view. It is a figure which shows the adjusting screw shown in FIG. 1, Comprising: (a) is a top view, (b) is sectional drawing. It is sectional drawing which shows the state which the hot water flow path opened. It is a figure which shows the state which the adjustment screw shown in FIG. 1 damaged. It is sectional drawing which shows the modification of one Embodiment of this invention. It is sectional drawing which shows the conventional high temperature hot water prevention valve. It is sectional drawing which shows the valve seat and adjustment screw shown in FIG. It is a perspective view which shows the valve body shown in FIG. It is a figure which shows the state which the valve body shown in FIG. 9 damaged.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High temperature hot water prevention valve 2 Housing 2a Rib 3 Hot water supply port 4 Water supply port 5 Discharge port 10 Valve body 11 Valve body part 12 Support ring 13 Rib 20 Valve seat 21 Body part 21a Rib 21b Screw part 22 Fixing part 22a Rib 22b Screw part 30 Actuator 40 Adjustment spring 50 Adjustment screw 60 Connection pipe 61 Projection 70 Connection pipe

Claims (6)

A housing provided with a hot water supply port, a water supply port and a discharge port, a valve body formed so as to be able to advance and retreat inside the housing, and a hot water flow path from the hot water supply port narrows as the valve body approaches, and the valve body is separated A valve seat in which a hot water flow path is expanded, an actuator that mixes hot water from the hot water supply port and water from the water supply port, senses the mixed hot water temperature, and moves the valve body forward and backward, and the valve body One end is in contact with the adjustment spring for adjusting the temperature of the hot water discharged from the discharge port, and an adjustment screw that is screwed into the valve seat and changes the length of the adjustment spring by changing the screwing position. A hot spring prevention valve,
The adjustment screw includes a head portion formed with a screw portion to be screwed with the screw portion of the valve seat, and a flange portion provided below the head portion and in contact with the other end portion of the adjustment spring,
The valve body connects a cylindrical valve body portion, a ring-shaped support ring portion that is positioned below the valve body portion and abuts against one end of the actuator, and the valve body portion and the support ring portion. With ribs,
A high-temperature hot water prevention valve characterized in that the mechanical strength of the collar portion of the adjusting screw is smaller than the mechanical strength of the rib of the valve body. The collar portion of the adjusting screw is formed in the radial direction, and is configured to receive a repulsive force from the adjusting spring and the actuator as a shearing force,
The rib of the valve body is formed in the axial direction of the cylindrical valve body portion, connects the bottom surface of the valve body portion and the upper surface of the support ring portion, and receives a repulsive force from the adjustment spring and the actuator as a compressive force. The high temperature hot water prevention valve according to claim 1, wherein the high temperature hot water prevention valve is configured as follows.   The high temperature hot water prevention valve according to claim 1 or 2, wherein a protrusion means is provided in contact with or close to the upper end surface of the valve seat, and the valve seat is held by the protrusion means.   The protrusion means is a protrusion provided on a connecting pipe connected to the hot water supply port, or a protrusion provided on a ring-shaped plate member installed on the hot water supply port in contact with the connection pipe connected to the hot water supply port. The high temperature hot water prevention valve according to claim 3.   The high temperature hot water prevention valve according to claim 1 or 2, wherein the other end portion of the actuator is locked to a rib formed on the housing, and the rib is held by holding means.   6. The high temperature hot water prevention valve according to claim 5, wherein the holding means is an end face of a connecting pipe connected to a hot water supply port.

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