JP2009092093A - Flow control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flow control valve which can solve the problem that when an atmospheric temperature drops in winter or the like in a state that hot or cold water remains in a flow control valve after used, the hot or cold water freezes and a casing of the flow control valve or the like may be broken, and that, as for a conventional one in which sponge or the like is arranged in a water passage, since the sponge or the like always contacts with the hot or cold water, the valve is influenced by chlorine or the like melted in city water, and degraded. <P>SOLUTION: A bearing member 4 is provided movably in the axial direction of valve shaft, and a coil spring 5 is provided which biases the bearing member 4 to valve body 13 side by a biasing force larger than a reaction force when the valve shaft moves in a valve opening direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a flow rate control valve that controls the flow rate of hot water by increasing and decreasing the opening degree with a motor.

  This type of flow control valve is used in a hot water supply device or the like, and is screwed into a valve shaft engaged with an axis of rotation of a motor rotation shaft so as to be movable back and forth, and a screw portion formed on the peripheral surface of the valve shaft. And a bearing member that holds the valve shaft rotatably and moves the valve shaft in the axial direction when the valve shaft rotates, and controls the opening and closing of the valve opening with a valve body provided at the tip of the valve shaft Thus, the flow rate of the hot water passing through the valve port is controlled.

  In such a flow control valve, if the temperature drops in winter or the like with hot water remaining inside after use, the hot water in the interior may freeze and the casing of the flow control valve may be damaged.

In order to prevent such damage caused by freezing of hot water remaining in the interior, a sponge is inserted into the space where the hot water remains (for example, see Patent Document 1), or a rubber material containing a bubble capsule is inserted inside. (For example, refer patent document 2), the thing which eased the pressure which raises by freezing of hot water by compressing and deforming sponge and a rubber raw material, and prevented the damage by freezing is known.
JP-A-10-281556 (FIG. 1) Japanese Patent Laying-Open No. 2003-64263 (FIG. 2)

  Since both of the above conventional ones are always in contact with hot water, it may be deteriorated by the influence of chlorine or the like melted in tap water.

  In view of the above problems, an object of the present invention is to provide a flow control valve in which such a problem does not occur.

  In order to solve the above-mentioned problems, a flow control valve according to the present invention is screwed into a valve shaft engaged with a rotating shaft of a motor so as to be able to advance and retreat in an axial direction, and a screw portion formed on a peripheral surface of the valve shaft. And a bearing member that moves the valve shaft in the axial direction when the valve shaft rotates, and increases or decreases the opening degree of the valve port with a valve body provided at the tip of the valve shaft. In the flow control valve for controlling the flow rate of hot water passing through the valve port, the bearing member is provided movably in the axial direction of the valve shaft, and the bearing member is moved when the valve shaft is moved in the valve closing direction. The urging means for urging the valve body with an urging force larger than the reaction force is provided on the opposite side of the valve body with the bearing member interposed therebetween.

  Although the bearing member is movably provided, the urging force to the valve element side is set larger than the reaction force when the valve shaft moves in the valve closing direction, so that the bearing member does not normally move. However, when the hot water in the portion where the valve body exists freezes and expands to increase the pressure, the bearing member moves away from the valve opening against the urging force. This movement increases the volume of the space in which the hot water remains, so that the increase in pressure is alleviated. In addition, since the biasing means is provided on the opposite side of the valve body across the bearing member, the biasing means can be arranged in a space not in contact with hot water and the influence of components in hot water causing deterioration. It becomes difficult to receive.

  Further, when the bearing member moves against the urging force by the urging means, the valve body moves to open the valve port, so that the pressure is released through the opened valve port. An increase in pressure can be reliably avoided.

  As is apparent from the above description, the present invention can prevent the flow rate control valve from being damaged due to a pressure increase due to freezing of hot water. And since the urging means can be arranged in a space where the hot water remains without touching the hot water with no sponge or rubber member, the urging means is affected by chlorine in the hot water. Therefore, the biasing means is not deteriorated by chlorine or the like.

  With reference to FIG. 1, reference numeral 1 denotes a flow rate control valve according to the present invention, and a flow rate detection unit 11 is provided on the water inlet side of the casing 10. The flow rate detection unit 11 includes a rotating blade on the turbine that is rotated by flowing water. In addition, a permanent magnet is attached to the rotary blade, and the rotational speed of the rotary blade is detected by a magnetic sensor (not shown) using a Hall element, and the flow rate can be calculated from the rotational speed.

  Hot water that has passed through the flow rate detector 11 is discharged from the valve chamber C through the valve port 12. The valve port 12 is opened and closed by the valve body 13, and the flow rate passing through the valve port 12 is adjusted by increasing or decreasing the opening degree of the valve port 12 according to the position of the valve body 13. The valve body 13 is formed at the tip of the shaft portion 14, and the shaft portion 14 is attached to the rotary shaft 3 so as to move integrally. The shaft portion 14 and the rotary shaft 3 constitute a valve shaft.

  A screw portion 32 is formed on the outer peripheral surface of the rotating shaft 3. On the other hand, a bearing member 4 is attached to the casing 10, and an inner screw portion 41 formed on the bearing member 4 and a screw portion 32 of the rotary shaft 3 are screwed together.

  A geared motor 2 is provided with a cylindrical output shaft 21. A spline 22 is formed on the inner peripheral surface of the output shaft 21, and a spline 31 that engages with the spline 22 is formed on the rotary shaft 3. ing. Therefore, when the output shaft 21 rotates, the rotating shaft 3 rotates integrally with the output shaft 21, and in this state, the rotating shaft 3 can move back and forth along the axial direction. Therefore, if the bearing member 4 is fixed, the output shaft 21 rotates forward and backward, so that the rotary shaft 3 moves forward and backward.

  Since the shaft portion 14 is integrally attached to the rotating shaft 3 as described above, the valve body 13 also moves back and forth in conjunction with the moving back and forth of the rotating shaft 3. And the opening degree of the valve port 12 changes between a valve closing state and a fully open state by the advance / retreat position of the valve body 13.

  The conventional bearing member 4 is fixed to the casing 10, but in the present invention, the bearing member 4 is mounted in the casing 10 so as to be movable in the axial direction of the rotary shaft 3. As shown in FIG. 2, the pair of upper and lower rotation prevention portions 42 formed on the bearing member 4 sandwich the ribs 16 formed on the inner peripheral surface of the casing 10 so that the bearing member 4 is prevented from rotating. I made it.

  The bearing member 4 is biased toward the valve body 13 by the coil spring 5 and is pressed against a stopper portion 15 formed in the casing 10. If a reaction force when moving the valve body 13 in the valve opening direction acts on the bearing member 4, the reaction force is received by the stopper portion 15, so the bearing member 4 does not move by the reaction force. Further, the reaction force when the valve body 13 is closed from the opened state acts on the bearing member 4 in the direction away from the stopper portion 15, but the urging force of the coil spring 5 is set to be larger than this reaction force. Thus, the bearing member 4 is prevented from moving by the reaction force.

  With the above-described configuration, for example, when water remaining in the valve chamber C freezes in a state where the outside air temperature decreases, such as in winter, the pressure in the valve chamber C increases. Since the valve port 12 is closed by the valve body 13, the increased pressure is not released from the valve port 12. Since the conventional flow rate control valve does not have a structure for releasing the increased pressure, there is a possibility that any weaker portion may be damaged. However, in the present invention, the bearing member 4 is attached to the coil spring 5 as shown in FIG. It moves to the motor 2 side against the force. Since the volume of the valve chamber C is expanded by this movement, an increase in the pressure in the valve chamber C is mitigated. In addition, since the coil spring 5 is provided on the opposite side of the valve body 13 with the bearing member 4 interposed therebetween, the coil spring 5 can be disposed in the valve chamber C, and is affected by components in hot water that cause deterioration. It becomes difficult.

  When the bearing member 4 moves, the valve body 13 connected to the shaft portion 14 together with the rotating shaft 3 also moves to the motor 2 side, that is, the valve opening side. When the pressure continues to increase and the moving force of the bearing member 4 reaches a predetermined amount L, the valve port 12 is opened and the pressure is released through the valve port 12. Therefore, the bearing member 4 does not have to move further to the motor 2 side. When the outside air temperature rises and freezing is released and the pressure decreases, the bearing member 4 is returned to the original position by the urging force of the coil spring 5, so that the flow control valve 1 can operate normally again.

  In addition, this invention is not limited to an above-described form, You may add a various change in the range which does not deviate from the summary of this invention.

The figure which shows the structure of one embodiment of this invention II-II sectional view Diagram showing the state when frozen

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flow control valve 2 Motor 3 Rotating shaft 4 Bearing member 5 Coil spring 12 Valve port 13 Valve body 14 Shaft part C Valve chamber

Claims (2)

  The valve shaft is engaged with the rotation shaft of the motor so as to be able to advance and retreat in the axial direction, and is screwed into a screw portion formed on the peripheral surface of the valve shaft, so that the valve shaft is rotatably held and the valve shaft is rotated. And a bearing member that moves the valve shaft in the axial direction when the valve shaft is opened, and the valve body provided at the tip of the valve shaft controls the flow rate of hot water passing through the valve port by increasing and decreasing the opening degree of the valve port In the control valve, the bearing member is movably provided in the axial direction of the valve shaft, and the bearing member is biased toward the valve body with a biasing force larger than a reaction force when the valve shaft moves in the valve closing direction. A flow control valve characterized in that the means is provided on the opposite side of the valve body with the bearing member interposed therebetween.   2. The flow rate control valve according to claim 1, wherein when the bearing member moves against the urging force of the urging means, the valve body moves to open the valve port.

Images