JPS6114769Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a water hammer prevention mechanism for automatic water stop valves that closes the water stop valve to stop water when a set amount of water is discharged, and its purpose is simple. To provide a water hammer prevention mechanism for an automatic water shutoff faucet, which has a simple structure and can reliably prevent water hammer during automatic water shutoff over a wide range of dynamic water pressure.

First, to explain the automatic water stop valve shown in the drawings, the main body 10, which is a mixed faucet, is shown in FIGS. 1 and 4.
As shown in the figure, it is a horizontally elongated hollow body, and handles 41, 41 are attached to both sides of the front side, respectively, and sockets 44 are attached to both sides of the back side, respectively. These sockets 44 have a flow rate adjustment valve 45 and a check valve 4.
6 is incorporated, and hot water or water reaches the front chamber 11 provided inside both sides of the main body 10 through the socket 44. The handle 44 has a handle 44
A spindle 42 is attached that moves forward and backward by the rotation of the front chamber 11.
A valve portion 43 is formed by the opening in the main body 10 . A measuring chamber 1 partitioned off by a partition wall 13 is provided in the central front part of the main body 10. One end of a discharge pipe 48 is rotatably attached to the discharge port 47 below this measuring chamber 1. Hot water flowing from each front chamber 11 is discharged from a discharge pipe 48 through a hole 49 provided on the rear surface of the partition wall 13 through the metering chamber 1.

On the other hand, the metering and water shutoff mechanism includes a metering section consisting of an impeller 15 disposed from above in the metering chamber 1, a water shutoff valve section 2 disposed from the rear end opening of the main body 10 behind the partition wall 13, and It is composed of a mechanism section arranged above, and includes a water stop valve section 2 and a partition wall 13.
The impeller 15 is rotated by hot water flowing into the measuring chamber 1 from the hole 49, and the rotation of the impeller 15 is transmitted to the main shaft 21 via the reduction gear train 16, 17, pinion 18, gear 19, and friction clutch 20. introduce. An operating dial 14 located at the center of the top surface of the main body 10 is fixed to the main shaft 21, and the gear 19 is attached via a friction clutch 20, and a cam 3 is also attached to rotate in conjunction with the main shaft 21. . However, in this cam 3, a pin 22 that passes through the main shaft 21 is engaged with a radial groove provided on the inner peripheral surface, the width of which is wider than the diameter of the pin 22, so that the cam 3 has no play with respect to the main shaft 21 in the rotation direction. It has a corner. Also, this cam 3 has two cam surfaces 3 on its bottom surface.
1 and 32, the upper end of the control rod 4 contacts the outer cam surface 31, and the upper end of the drive rod 5 contacts the inner cam surface 32, respectively. The control rod 4 has its lower end positioned in the water stop valve section 2, which is composed of a ball 26, a valve seat 27, and a cylindrical body 28 that houses these and has an axis in the front and back direction, so that it can freely slide in the vertical and axial directions. It is equipped with a piston 36, which together with a cylinder 35 constitutes a doss pot 8, in the center. This dart pot 8 uses hot water flowing inside the main body 10 as a working fluid to alleviate water hammer during automatic water shutoff.

In the figure, reference numeral 6 denotes a shaft that supports the impeller 16 and the reduction gear train 17, and is arranged parallel to the control rod 4. The drive rod 5, which also supports the reduction gear train 16 and the pinion 18, is also a shaft. It is parallel to the control rod 4 and the shaft 6, and is slidable in the vertical and axial directions. The drive rod 5 has an engaging body 23 at its lower end that engages with the blades of the impeller 15 to prevent rotation of the impeller 15, and is biased upward by a spring 24.

As is clear from FIG. 5, the control rod 4, shaft 6, and drive rod 5 are housed and supported within a cartridge 7 consisting of a pair of upper and lower cases 51, 52 and a lid 53 that closes the top surface. The impeller 15, reduction gear train 16, 17, and dart pot 8 are also housed in this cartridge 7. Incidentally, the case 52 housing the impeller 15 has an open side surface. The upper part of the cartridge 7 has a substantially circular horizontal cross section, and the control rod 4, drive rod 5, and shaft 6 are arranged at the vertices of a triangle within the cartridge 7, thereby achieving miniaturization.

The cartridge 7 is inserted from above into a cylindrical portion 12 that projects from the upper central surface of the main body 10. The water stop valve section 2 is disposed from the rear end opening of the main body 10. A cap 50 is attached to this rear end opening and closed. 29 is a wire mesh. The operating handle 14 attached to the main shaft 21 is placed over the outer surface of the cylindrical portion 12, and a cover 25 located on the inner circumference of the operating handle 14 is attached to the main shaft 21 in a rotatable and water-tight manner. The outer peripheral surface of the cover 25 is connected to the cylindrical portion 12
It is screwed onto the inner peripheral surface of the upper end in a water-tight manner. Now, one block consisting of the operating handle 14 and each member attached to the main shaft 21 is attached, and the cartridge 7 is fixed by pressing with the cover 25.

On the outer circumferential surface of the operation dial 14, "continuous water discharge" and a water discharge amount scale are written in the circumferential direction with "stop" in between, and when the "stop" position is aligned with the pointer on the main body 10, Control rod 4 is dart pot 8
The upper end of the V-shaped recess 33 in the cam surface 31 of the cam 3 is caused by the water pressure applied to the piston 38 (if a return spring is provided, depending on the spring force of the return spring).
The ball 26 of the water stop valve section 2 is not pushed, and the ball 26 contacts the valve seat 27 with water pressure, thereby closing the water stop valve section 2 as shown in FIG. Operate both handles 41, 41 to close each valve part 43, 43.
Even if it is open, water is stopped by the water stop valve part 2. Next, by rotating the operation dial 14 and aligning the numerical value corresponding to the desired water discharge amount on the scale with the pointer, the main shaft 2 that rotates together with the operation dial 14 will rotate.
1, the cam 3 also rotates, and in order to push the control rod 4 downward, the ball 26 of the water stop valve part 2 is pushed by the lower end of the control rod 4 and is separated from the valve seat 27, as shown in FIG. Open the water stop valve part 2. If the valve part 43 is open at this time, the hot water passes through the bottom of the water stop valve part 2 and is metered through the water stop valve part 2 and the hole 49 from the rear end opening of the cylinder body 28 where the wire mesh 29 is disposed. It flows into the chamber 1 and is discharged from the discharge pipe 48. At this time, the impeller 15 is rotated by the hot water flowing through the metering chamber 1, and the cam 3 is rotated at a very low speed via the reduction gear train 16, 17, the friction clutch 20, and the main shaft 21. When the set amount of water is discharged, the cam surface 3 of the cam 3
1 approaches the control rod 4, and then the control rod 4 moves upward while sliding on the wall of the recess 33, causing the cam 3 to rotate more rapidly than the rotation of the main shaft 21 within the range of the play angle. While doing so, it falls into recess 33. As a result, the water stop valve section 2 closes again.

Turn the operation dial 14 in the opposite direction from the "stop" position,
In other words, when the impeller 15 is rotated in the same direction as the rotation direction and set to "continuous water discharge", the control rod 4 is pushed out from the recess 33 of the cam surface 31 and the water stop valve section 2 opens. However, at this time, the drive rod 5 falls into a recess (not shown) provided in the cam surface 32 and moves upward, engaging the engaging body 23 with the blades of the impeller 15 and preventing the rotation of the impeller 15. . Engagement body 2
3 locks the rotation of the impeller 15 during continuous water spraying for the following reason. That is, since the direction of rotation of the operation dial 14 when setting to continuous water discharging is the same as the direction of rotation due to the input from the impeller 15 as described above, it is only necessary to restrict the rotation range of the operation handle 14 in this rotation direction. Continuous water spraying can be performed until the operating handle 14 is manually returned to the "stop" position, but in this case as well, when the impeller 15 rotates, the friction clutch 20 stops all water spraying during the continuous water spraying period. I don't like it because I have to be there. For this reason, the rotation of the impeller 15 is locked during continuous water spraying.

By the way, if the cam 3 is fixed to the main shaft 21 without any play, the wall surface of the recess 33 must be formed into an inclined V-shape because it is necessary to push out the control rod 4 from the recess 33 when discharging water. In order to increase the amount of water that can be set, the rotation of the cam 3 by the input from the impeller 15 must be made at a very low speed, so the water does not easily stop when the water is automatically stopped, making it difficult to set the amount of water accurately. For this purpose, as mentioned above, an angle of play is provided between the main shaft 21 and the cam 3, and when the water is automatically stopped, the cam plate 3 is rotated within the range of the play angle by input from the control rod 4. This is to ensure that the water is stopped, but this has caused water hammer to become a problem. Therefore, a dart pot 8 is formed to apply a brake to the movement of the control rod 4 and prevent water hammer.

However, when attempting to reduce the cost and assembly effort by using hot water flowing through the channel as the working fluid in this dart pot 8, it is difficult to obtain reliable operation compared to the case where the working fluid is sealed in the cylinder 35. There is a problem. In other words, when using this automatic stop valve for the first time, since there is air inside, it must be possible to bleed air when introducing hot water as the working fluid into the cylinder 35, and this air bleed is necessary when the dash pot is used. It must not impair the original function of 8. For this purpose, as shown in FIG. 6, a device having an air vent equipped with a valve that opens and closes as the control rod 4 slides has been proposed. To explain this conventional example, the cylinder 35 has one end communicating with the upstream side of the water stop valve section 2, and an introduction groove 37 having a slightly larger cross-sectional area on the flow path side is formed on the inner circumferential surface of the cylinder 35. On the third side, drain grooves 38 having a slightly smaller cross-sectional area are cut in the axial direction. Although the piston 36 of the control rod 4 has its O-ring 39 in contact with the inner peripheral surface of the cylinder 35,
The front and back of the piston 36 are drain grooves 38 to introduction grooves 3.
It is connected by 7. Here, the introduction groove 33 is for introducing water into the pressure chamber 9 which is closer to the cam 3 than the piston 36 when the water stop valve part 2 is opened, and the drain groove 38 is for introducing water into the pressure chamber 9 which is closer to the cam 3 than the piston 36. Due to the resistance obtained by passing water in chamber 9, control rod 4
It provides a brake on the movement of. As described above, an axial groove 54 is provided at one end of the control rod 4 as a structure for air venting. The pressure chamber 9 is opened before and after 40, and when the water is stopped, the groove 5 is opened.
4 is located closer to the cam 3 than the seal packing 40, so that the pressure chamber 9 is sealed except for the drain groove 38. In this way, the seal packing 40 and the groove 54 of the control rod 4 act as an air vent only when necessary. but,
In this conventional example, the dimensional accuracy of the groove 54 of the control rod 4 must be kept high, otherwise the air may not be fully vented and air may remain, or the water must be pushed out only through the drain groove 38 during automatic water shutoff. Since the water in the pressure chamber 9 is also discharged through the groove 54, the braking force at the dart pot 8 may be reduced and the time required for the water to stop may become unreasonable. This is especially true when the hydrodynamic pressure is as high as 5 kg/cm ² . Further, the introduction groove 37 and the drain groove 38 must be provided in the cylinder 35, and the groove 54 must be provided in the control rod 4, making the structure complicated.

An embodiment of the present application that eliminates this drawback is shown in FIG. The difference from the conventional example is that the piston 3 except for the part where the introduction groove 37 is provided on the inner surface of the cylinder 35
6 slides in a watertight manner through an O-ring 39, and the drain groove 38 is also used as an air vent to use the resistance when discharging the water in the pressure chamber 9 as a braking force. Seal packing 4
0, and the pressure chamber 9 is always communicated with the downstream side of the water stop valve part 2 through this drain groove 38. The O-ring 55 is provided to prevent water from passing between the piston 36 and the cylinder 35 and leaking from the drain groove 38 due to high water pressure when the water is stopped.

When the water stop valve section 2 is open, water flows into the pressure chamber 9 through the introduction groove 37, and the pressure chamber 9
If there is air, it is discharged through the drain groove 38, and the pressure chamber 9 is filled with water. When the water is stopped, the pressure chamber 9 is sealed except for the drain groove 38,
The resistance when the water in the pressure chamber 9 is discharged through the drain groove 38 creates the function as the dumppot 8. In this case, the higher the hydrodynamic pressure, the greater the viscosity coefficient between the O-ring 39 and the inner surface of the cylinder 35, so that the sliding speed of the control rod 4 can be reliably adjusted not only when the water pressure is low but also when it is high. Water hammer can be prevented by reducing the

As described above, in the present invention, in a dart pot whose working fluid is water flowing through a flow path, a drain groove for discharging water from a pressure chamber is opened on the downstream side of the water stop valve part. Therefore, this drain groove also functions as an air vent, which is easy to manufacture and can reliably prevent water hammer regardless of the level of water pressure.

[Brief explanation of the drawing]

FIG. 1 is a cutaway plan view of an embodiment of an automatic water stop valve.
Figure 2 is a vertical cross-sectional view of the same as above, Figure 3 is an enlarged vertical cross-sectional view of the main part of the same as above, Figure 4 is a horizontal cross-sectional view of the main body, Figure 5 is a cross-sectional view of the cartridge, and Figure 6 is a conventional dash pot. FIG. 7 is a cross-sectional view of an embodiment of the present invention, in which 2 is a water stop valve, 4 is a control rod,
8 is a dash pot, 35 is a cylinder, 36 is a piston, 38 is a drain groove, and 40 is a seal packing.

Claims (1)

[Scope of utility model registration request] A measuring section that measures the amount of water passing through the flow path, a water stop valve installed in the middle of the flow path, and a water stop valve that opens and closes by sliding in the axial direction in conjunction with the output of the measuring section and operation input. In an automatic water stop valve equipped with a control rod,
A piston that slides in watertight contact with the inner surface of the cylinder, one end of which communicates with the flow path upstream of the water stop valve, and the other end of which communicates with the flow path downstream of the water stop valve via a drain groove. A cylinder and a seal pad are provided on the control rod and constitute a dart pot that uses water guided from a flow path as a working fluid, and the water drain groove is disposed at the other end of the cylinder and slides in watertight contact with the control rod. A water hammer prevention mechanism for automatic water stop valves formed between