JP2016023906A - Water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water heater that includes a hot water path 6 connecting with a hot water supply terminal 6a branching off from a downstream end of a hot water tap path 5 downstream from a heat exchanger 1 and a hot water running path 7 connecting a bathtub 3 and that is reducible in cost by using one valve as both a water amount control valve, reducing the amount of water fed to the heat exchanger, and a hot water running valve by a single valve device.SOLUTION: A three-way valve 8 as a single valve device is provided at a downstream end of a hot water tap path 5. The three-way valve includes: a valve chamber 811 communicating with the hot water tap path 5; a first valve seat 813 which is located at one lengthwise end of the valve chamber and has a first valve hole 812 opened to communicate with a hot water supply path 6; a valve enclosure 81 which is located at the other lengthwise end of the valve chamber, and has a second valve seat 815 having a second valve hole 814 opened to communicate with a hot water running path 7; a valve shaft 84 which is driven by a motor 82 in the lengthwise direction of the valve chamber through a feed screw mechanism 83; a first valve body 85 which is mounted on the valve shaft opposite the first valve seat in the valve chamber; and a second valve body 86 which is mounted on the valve shaft opposite the second valve seat in the valve chamber.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hot water supply comprising a heat exchanger for hot water supply, a hot water supply passage downstream of the heat exchanger, a hot water supply passage branched from the downstream end of the hot water supply passage, and a hot water filling passage connected to a bathtub. Relates to the device.

  In a conventional hot water supply apparatus, a water amount adjusting valve is provided in a water supply path upstream of a heat exchanger for hot water supply, and a hot water filling valve including an electromagnetic valve is provided in a hot water filling path (for example, Patent Documents). 1). If the temperature of the hot water does not reach the set temperature even if the combustion amount of the burner that heats the heat exchanger is maximized, the amount of water flow to the heat exchanger is reduced by the water amount control valve, and the hot water temperature is set to the set temperature. In addition, the hot water filling valve is opened so that the hot water can be filled in the bathtub.

  However, in this case, since a hot water filling valve is required in addition to the water amount adjustment valve, there is a problem that the cost increases.

JP 2011-122807 A

  In view of the above, the present invention provides a hot water supply device that can reduce costs by using a single valve device that has both the function of a water amount adjusting valve and the function of a hot water filling valve. That is the issue.

  In order to solve the above-mentioned problems, the present invention is connected to a hot water supply heat exchanger, a hot water supply passage downstream of the heat exchanger, and a hot water supply passage and a bathtub connected to a hot water supply terminal branched from the downstream end of the hot water supply passage. A hot water supply device comprising a hot water supply passage, wherein a three-way valve is provided at a branch portion between the hot water supply passage and the hot water supply at the downstream end of the hot water supply passage, and the three-way valve is connected to the hot water supply passage, A first valve seat, which is located at one end in the longitudinal direction and has a first valve hole communicating with the hot water supply passage, and a second valve hole, which is located at the other longitudinal end of the valve chamber and communicates with the hot water filling passage, is established. A valve housing having a second valve seat, a valve shaft driven by a motor in the longitudinal direction of the valve chamber via a feed screw mechanism, and mounted on the valve shaft so as to face the first valve seat in the valve chamber. A first valve body, and a second valve body mounted on the valve shaft so as to face the second valve seat in the valve chamber, the first valve body contacting the first valve seat. When the valve shaft moves from the stroke end position in the backward movement direction to the forward movement direction, the first valve is first moved to the forward movement direction and the direction in which the second valve body approaches the second valve seat as the backward movement direction. The flow of hot water supplied to the hot water supply passage gradually decreases as the body approaches the first valve seat, and then the second valve body is separated from the second valve seat so that hot water is supplied to the hot water filling passage. It is characterized by that.

  According to the present invention, it is possible to reduce the amount of hot water supplied to the hot water supply passage while the hot water supply to the hot water supply passage is stopped by moving the valve shaft from the stroke end position in the backward movement direction to the forward movement direction. it can. Thereby, the water flow amount to a heat exchanger will reduce and the same function as the water amount adjustment valve of the conventional hot water supply apparatus will be exhibited. Further, if the valve shaft is moved in the forward movement direction to a position where the second valve body is separated from the second valve seat, hot water is supplied to the hot water filling passage, Perform the same function. Thus, according to the present invention, since the three-way valve, which is a single valve device, has both the function of the water amount adjusting valve and the function of the hot water filling valve, the conventional example in which the water amount adjusting valve and the hot water filling valve are provided separately. As a result, the cost can be reduced.

  By the way, when the second valve body is separated from the second valve seat and a power failure occurs while supplying hot water to the hot water supply path, if the three-way valve is maintained in this state, the burner burns due to the power failure. Since it is stopped, cold water is poured into the bathtub through the hot water filling path without being heated by the heat exchanger, and the hot water temperature of the bathtub is lowered. Therefore, in the present invention, a return spring that biases the valve shaft in the backward movement direction is provided, and at the time of a power failure, the valve shaft moves in the backward movement direction by the biasing force of the return spring, and the second valve body causes the second spring to move to the second movement direction. It is desirable that the valve hole be closed. According to this, at the time of a power failure, it can prevent that cold water is poured into a bathtub via a hot water filling path.

  Here, at the time of a power failure, the torque of the return spring that is transmitted to the motor is larger than the detent torque of the motor so that the valve shaft moves in the backward movement direction due to the bias of the return spring. The urging force may be set, but in order to hold the valve shaft in the required adjustment position, it is necessary to continue supplying the electric power necessary to cancel the torque due to the urging force of the return spring to the motor. Power consumption increases.

  Therefore, when the return spring is provided as described above, a clutch that is fastened by energizing the solenoid is interposed in the power transmission path that transmits the power from the motor to the feed screw mechanism, and the urging force of the return spring is changed to the clutch. It is desirable that the torque by the urging force of the return spring transmitted to the motor at the time of fastening is set to be smaller than the detent torque of the motor. According to this, even when energization to the motor is stopped when the clutch is engaged, the valve shaft is held at the required adjustment position against the biasing force of the return spring by the detent torque of the motor. And since the electric power supplied to the solenoid required to maintain the clutch in the engaged state is small, the power consumption can be reduced. At the time of a power failure, the energization to the solenoid is stopped and the clutch is released, so that the detent torque of the motor does not act on the feed screw mechanism, and the valve shaft moves in the backward movement direction by the urging force of the return spring.

Explanatory drawing which shows the hot-water supply apparatus of embodiment of this invention. (A) (b) Sectional drawing which shows the action | operation of the three-way valve provided in the hot water supply apparatus of embodiment.

  Referring to FIG. 1, reference numeral 1 denotes a heat exchanger for hot water supply, 2 denotes a heat exchanger for bathing, and these heat exchangers 1 and 2 are heated by burners 1a and 2a, respectively. The bath-heating heat exchanger 2 is connected to the bathtub 3 via the forward path 3a and the return path 3b. The water in the bathtub 3 is heated while being circulated through the heat exchanger 2 by the operation of the circulation pump 3c interposed in the forward path 3a. The hot water supply heat exchanger 1 and the bath reheating heat exchanger 2 are illustrated separately in FIG. 1, but are actually built in one box.

  The hot water supply heat exchanger 1 heats the cold water from the upstream water supply passage 4 and discharges hot water to the downstream hot water supply passage 5. In the water supply path 4, a water amount sensor 4 a and a water temperature sensor 4 b are disposed, and further, a bypass path 4 c that connects the water supply path 4 and the hot water supply path 5 in parallel with the heat exchanger 1 is provided. A hot water temperature sensor 5a is provided in the portion of the hot water outlet 5 downstream from the junction of the bypass 4c. Then, the amount of heat necessary to discharge hot water at the set temperature is calculated from the detected water amount of the water amount sensor 4a and the detected water temperature of the water temperature sensor 4b, and the combustion amount of the burner 1a is feedforward controlled in accordance with this heat amount. The combustion amount of the burner 1a is corrected by feedback control so that the hot water temperature detected by the hot water temperature sensor 5a becomes the set temperature.

  From the downstream end of the hot water supply path 5, a hot water supply path 6 connected to a hot water supply terminal 6a such as a hot water tap and a hot water supply path 7 connected to the bathtub 3 are branched via the forward path 3a. In the present embodiment, a three-way valve 8 is provided at a branch portion between the hot water supply passage 6 and the hot water filling passage 7 at the downstream end of the hot water supply passage 5.

  The three-way valve 8 includes a valve chamber 811 that communicates with the hot water supply passage 5 and a first valve hole 812 that is located at one end in the longitudinal direction of the valve chamber 811 (lower end in FIG. 1) and communicates with the hot water supply passage 6. A valve housing 81 having a valve seat 813 and a second valve seat 815 having a second valve hole 814 that is located at the other longitudinal end of the valve chamber 811 (upper end in FIG. 1) and communicates with the hot water passage 7. And a valve shaft 84 driven in the longitudinal direction of the valve chamber 811 by the motor 82 via the feed screw mechanism 83, and a valve shaft 84 mounted on the valve shaft 84 so as to face the first valve seat 813 in the valve chamber 811. One valve body 85 and a second valve body 86 mounted on the valve shaft 84 so as to face the second valve seat 815 in the valve chamber 811 are provided. The direction in which the first valve body 85 approaches the first valve seat 813 (downward) is the forward movement direction, and the direction in which the second valve body 86 approaches the second valve seat 815 (upward) is the backward movement direction. When the shaft 84 moves in the forward movement direction from the stroke end position in the backward movement direction (position shown in FIG. 1), first, the first valve body 85 is supplied to the hot water supply passage 6 by approaching the first valve seat 813. The hot water flow rate gradually decreases, and then the second valve body 86 is separated from the second valve seat 815 so that the hot water is supplied to the hot water filling passage 7.

  More specifically, the first and second valve bodies 85 and 86 are slidably inserted on the valve shaft 84. Further, the first stopper 841 formed of a snap ring that restricts the movement of the first valve body 85 relative to the valve shaft 84 at a fixed position, and the movement of the second valve body 86 in the backward movement direction relative to the valve shaft 84. A second stopper 842 made of a snap ring that regulates at a fixed position, and is contracted between the first valve body 85 and the second valve body 86, and the first and second valve bodies 85, 86 are connected to the first and second valve bodies 85, 86. An inter-valve spring 843 that biases the position regulated by the second stoppers 841 and 842 and a valve spring 844 that biases the second valve body 86 in the backward movement direction are provided. In a state where the valve shaft 84 is located at the stroke end position in the backward movement direction, the second valve body 86 is seated on the second valve seat 815 and the second valve hole 86 is closed, and then the first valve body 85 is located between the valves. While the spring 843 is compressed, the spring 843 is further moved in the backward movement direction and pushed up to the fully open position farthest from the first valve seat 813, and the second stopper 842 is separated from the second valve body 86. When the valve shaft 84 is moved in the forward direction from this state, the first valve body 85 moves in the forward direction following the valve shaft 84 and approaches the first valve seat 813 to be supplied to the hot water supply path 6. The warm water flow rate gradually decreases. Then, when the valve shaft 84 moves a predetermined stroke in the forward movement direction from the stroke end position in the backward movement direction, the first valve body 85 is seated on the first valve seat 813 as shown in FIG. 2 stopper 842 contacts second valve body 86. Thereafter, when the valve shaft 84 is further moved in the forward movement direction, the second valve body 86 follows the valve shaft 84 and compresses the inter-valve spring 843 and the valve spring 844 as shown in FIG. It moves in the moving direction, moves away from the second valve seat 815, and hot water is supplied to the hot water filling path 7. At this time, the first stopper 841 is separated from the first valve body 85, and then the first valve body is moved until the first stopper 841 contacts the first valve body 85 when the valve shaft 84 is moved in the backward movement direction. 85 remains seated on the first valve seat 813.

  Here, if the temperature of the hot water does not reach the set temperature even if the combustion amount of the burner 1a for heating the hot water supply heat exchanger 1 is maximized, the valve shaft 84 is moved from the stroke end position in the backward movement direction to the forward movement direction. The hot water supply amount to the hot water supply passage 6 is decreased in a state where the hot water supply to the hot water supply passage 7 is stopped. According to this, the amount of water flow to the heat exchanger 1 can be reduced, and the temperature of the hot water can be raised to the set temperature. When filling the bathtub 3 with hot water, the valve shaft 84 is moved to the stroke end position in the forward movement direction to separate the second valve body 86 from the second valve seat 815 and supply hot water to the hot water filling path 7. To do. Thus, according to this embodiment, since the three-way valve 8 which is a single valve device has both the function of the water amount adjustment valve of the conventional hot water supply device and the function of the hot water filling valve, The cost can be reduced as compared with a conventional hot water supply apparatus provided separately.

  The feed screw mechanism 83 includes a female screw member 831 fixed to the valve housing 81 and a male screw member 832 screwed into the female screw member 831, and is used for a later-described return spring 87 fixed to the valve shaft 84. The male screw member 832 is brought into contact with the spring receiver 87a. The power transmission path 88 for transmitting the power from the motor 82 to the feed screw mechanism 83 is provided with a reduction gear train composed of a plurality of gears. A spline sleeve 881a is connected to the gear 881 at the output end of the reduction gear train. The male screw member 832 is slidably fitted in a state in which the male screw member 832 is prevented from rotating on the spline sleeve 881a at the upper portion thereof. The valve shaft 84 is driven in the forward movement direction and the backward movement direction by advancing and retracting (screwing back and forth) while the male screw member 832 rotates.

  By the way, when the second valve body 86 is separated from the second valve seat 815 and a power failure occurs while hot water is supplied to the hot water passage 7, if the three-way valve 8 is maintained in this state, Since combustion of the burner 1a is stopped, cold water is poured into the bathtub 3 through the hot water filling path 7 without being heated by the hot water supply heat exchanger 1, and the hot water temperature of the bathtub 3 is lowered. Therefore, in the present embodiment, a return spring 87 that urges the valve shaft 84 in the backward movement direction is provided, and the valve shaft 84 moves in the backward movement direction by the urging force of the return spring 87 at the time of a power failure. The second valve hole 814 is closed by 86.

  A clutch 89 is interposed in the power transmission path 88. The clutch 89 is interposed between the motor 82 and the gear 882 at the input end of the reduction gear train, and includes an input side clutch body 891 that is prevented from rotating on the rotor shaft 82a of the motor 82 and a gear 882 at the input end. And an output side clutch body 892 rotatably supported by the rotor shaft 82a. The input side clutch body 891 is immovable in the axial direction of the rotor shaft 82a, while the output side clutch body 892 is movable in the axial direction of the rotor shaft 82a above the input side clutch body 891. When the output side clutch body 892 is moved to the input side clutch body 891 side (downward), the dog teeth 891a and 892a formed on both the input side clutch body 891 and the output side clutch body 892 mesh with each other, The clutch 89 is engaged.

  The output side clutch body 892 is urged in a direction (upward) away from the input side clutch body 891 by urging means 893 made of a coil spring or the like. Further, a solenoid 894 that moves the output side clutch body 892 to the input side clutch body 891 against the urging force of the urging means 893 is provided. In the present embodiment, the other end of the lever 894b whose one end is in contact with the output side clutch body 892 is engaged with the movable iron core 894a of the solenoid 894. When the movable iron core 894a is moved upward by energization of the solenoid 894, the output side clutch body 892 is pushed down to the input side clutch body 891 via the lever 894b, and the clutch 89 is engaged. .

  Normally, the solenoid 894 is energized to engage the clutch 89, the motor 82 is rotated in this state, and the power from the motor 82 is externally threaded by the feed screw mechanism 83 via the power transmission path 88 comprising a reduction gear train. 832 and the male screw member 832 is advanced and retracted to move the valve shaft 84. Then, when the valve shaft 84 has moved to the required adjustment position, the motor 82 is stopped. Here, the biasing force of the return spring 87 is set so that the torque generated by the biasing force of the return spring 87 transmitted to the motor 82 when the clutch 89 is engaged is smaller than the detent torque of the motor 82. Therefore, when the motor 82 is stopped, the valve shaft 84 is held at the adjustment position against the urging force of the return spring 87 by detent torque thereafter.

  At the time of a power failure, energization to the solenoid 894 is stopped, so that the output side clutch body 892 is separated from the input side clutch body 891 by the urging force of the urging means 893, and the clutch 89 is released. Therefore, the detent torque of the motor 82 does not act on the feed screw mechanism 83, the valve shaft 84 moves in the backward movement direction by the urging force of the return spring 87, and the second valve hole 86 closes the second valve hole 814. It is possible to prevent cold water from being poured into the bathtub 3.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to this. For example, the clutch 89 of the above embodiment is omitted, and the torque by the urging force of the return spring 87 transmitted to the motor 82 is such that the valve shaft 84 moves in the backward movement direction by the urging force of the return spring 87 in the event of a power failure. The biasing force of the return spring 87 may be set to be larger than the detent torque of 82. However, in this case, in order to hold the valve shaft 84 at a required adjustment position in a normal state, it is necessary to continue supplying power necessary for canceling the torque due to the urging force of the return spring 87 to the motor 82. Power consumption increases. On the other hand, according to the above embodiment, the valve shaft 84 is held at the required adjustment position against the urging force of the return spring 87 by the detent torque of the motor 82 even when the energization to the motor 82 is stopped. Since the power supply to the solenoid 894 necessary for maintaining the clutch 89 in the engaged state is small, the power consumption can be reduced, which is advantageous.

  DESCRIPTION OF SYMBOLS 1 ... Heat exchanger for hot water supply, 3 ... Bathtub, 5 ... Hot water supply path, 6 ... Hot water supply path, 6a ... Hot water supply terminal, 7 ... Hot water supply path, 8 ... Three-way valve, 81 ... Valve housing, 811 ... Valve chamber, 812 ... 1st valve hole, 813 ... 1st valve seat, 814 ... 2nd valve hole, 815 ... 2nd valve seat, 82 ... Motor, 83 ... Feed screw mechanism, 84 ... Valve shaft, 85 ... 1st valve body, 86 ... Second valve body, 87 ... return spring, 88 ... power transmission path, 89 ... clutch, 894 ... solenoid.

Claims (3)

A hot water supply apparatus comprising a heat exchanger for hot water supply, a hot water supply channel downstream of the heat exchanger, a hot water supply channel that branches from the downstream end of the hot water supply channel, and a hot water supply channel that continues to a bathtub. ,
A three-way valve is provided at the junction between the hot water supply channel and the hot water filling at the downstream end of the hot water supply channel,
The three-way valve has a valve chamber that communicates with the hot water outlet, a first valve seat that is located at one end in the longitudinal direction of the valve chamber, and has a first valve hole that communicates with the hot water supply passage, and at the other longitudinal end of the valve chamber. A valve housing having a second valve seat in which a second valve hole communicating with the hot water passage is located, a valve shaft driven by a motor in the longitudinal direction of the valve chamber via a feed screw mechanism, and a valve A first valve body mounted on the valve shaft so as to face the first valve seat inside the chamber; and a second valve body mounted on the valve shaft so as to face the second valve seat inside the valve chamber;
The direction in which the first valve body approaches the first valve seat is the forward movement direction, and the direction in which the second valve body approaches the second valve seat is the backward movement direction, and the valve shaft moves forward from the stroke end position in the backward movement direction. First, when the first valve body approaches the first valve seat, the flow rate of the hot water supplied to the hot water supply passage gradually decreases, and then the second valve body separates from the second valve seat and the hot water flows. A hot water supply apparatus characterized in that hot water is supplied to the stretch road.   A return spring that urges the valve shaft in the backward movement direction is provided, and in the event of a power failure, the valve shaft moves in the backward movement direction due to the urging force of the return spring, and the second valve body closes the second valve hole. The hot water supply apparatus according to claim 1, wherein   A clutch that is engaged by energizing a solenoid is interposed in a power transmission path that transmits power from the motor to the feed screw mechanism, and the urging force of the return spring is transmitted to the motor when the clutch is engaged. 3. The hot water supply apparatus according to claim 2, wherein the torque due to the biasing force of the spring is set to be smaller than the detent torque of the motor.

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