JP2592273Y2 - Water flow switch - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water flow switch used for a water heater or the like. More specifically, it is used as a safety switch to prevent water from being cooked by detecting the amount of water when a water heater or the like is burned.

[0002]

2. Description of the Related Art As shown in FIG. 1, a conventional basic structure of a water flow switch as described above is such that a reed switch 31 is fixed to a main body case 30, and a magnet is provided in the main body case 30 corresponding to the reed switch. When the magnet lever 33 is pushed upward by the water force supplied from the water inlet 35 at the lower end and the water outlet 36 at the upper end, When the magnet 32 approaches the reed switch 31 and the reed switch is turned on by the magnetic force and the water flow is stopped, the reed switch is lowered by its own weight and turned off. However, the conventional water flow switch has a magnet lever 33 and its mounting. Holder 37
Is formed by processing a metal plate, and is pivotally connected by a pivot pin 34 made of a metal bar. The mounting holder 37 is fixed to the main body case 30 by fastening screws 38. Also,
A rubber packing for insulation, a magnet 32 and a magnet retainer 39 are fitted into the magnet lever 33 so that mounting screws 4 are attached.
At 0, it was necessary to integrate them together.

[0003]

Therefore, in the water flow switch having the conventional structure as described above, a large number of small metal parts are required, so that the production and processing of the parts are required, and the magnet lever is not used. Adjustment is required to match the actual working flow rate to the target flow rate when assembling in the main body case. However, these adjustments are very difficult if the weight of the entire lever including the magnet is constant. Furthermore, since the magnet lever and its holder are pivotally connected by a single thin pin, aging after assembly,
There has been a problem that an operation failure due to a heat change or a water hammer phenomenon occurs.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide a water flow switch by incorporating a weight plate also serving as a magnet holder into a magnet lever. It is an object of the present invention to provide a small and inexpensive water flow switch that is easy to adjust to adjust the operating flow rate to the target flow rate when assembling parts, does not cause malfunction, has a small number of parts, and is easy to manufacture and assemble. Things.

[0005]

In order to achieve the above object, a water flow switch according to the present invention is provided with a magnet inside a main body case so as to correspond to a reed switch fixed at a fixed position on the outer surface of the main body case. When the lever with the body is swingably provided and the lever is pushed to the upstream side by water flow, the magnet body approaches the reed switch, the reed switch is turned on by magnetic force, and when water flow is stopped, it falls by its own weight. In the water current switch that is turned off, the magnet lever is integrally formed by resin formation with a lever portion having a pivot protruding on both left and right sides, and a magnet portion in which a magnet body is inserted in a magnet insertion portion,
In the magnet fitting part of the magnet part, a plate having a mass also serving as a balance weight is provided in the opening part in a plug-in manner, and a magnet holder of a resin molded product made of a ring body is press-fitted in the main body case. The magnet is fixed, the stand leg of the magnet holder is fitted in a groove formed in the inner surface of the main body case, and the pivot of the magnet lever is pivotally supported on the stand leg in an uneven fitting manner.

[0006]

[0007]

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A main body case 10 has a hollow short cylindrical shape as shown in FIGS.
Is provided with a water outlet 12 at the other end (upper end), and is made of a resin molded product or a nonmagnetic metal.

As shown in FIGS. 4 to 7, the magnet lever 3 has a lever portion 3a and a magnet portion 3b integrally formed. The magnet portion 3b is box-shaped to form a magnet fitting portion 5 inside. Pivot shafts 4 composed of short axis pins are integrally formed on the lever portion 3a so as to protrude on both left and right sides.

The upper surface of the magnet fitting portion 5 is open, and the plate 6 is inserted into the opening from the side to cover and cover the opening, thereby preventing the magnet 2 from dropping and popping out. Using the plate 6 as a weight, the operation of the magnet lever 3 by the water flow is adjusted to match the target flow rate.

When the plate 6 is inserted and set at a fixed position, as shown in FIG. 6, a pull-out preventing claw 14 provided in one of the insertion holes 3c is engaged with an edge of the plate to pull out. Prevent escape.

The magnet holder 7 is for mounting the magnet lever 3 and, as shown in FIG. 2 and FIG.
8 and the stopper 13 for determining the starting position of the magnet lever 3 are integrally formed.

The magnet holder 7 is attached to the main body case 10 by forced press-fitting from the water inlet 11 side, and is immovably integrated at a fixed position.

When the magnet holder 7 is pressed into the main body case 10, the magnet lever 3 is attached to the stand leg pieces 8, 8 in advance. Leg piece 8
8 are provided with pin holes 8a.
a · 8a, a pivot 4 · 4 projecting from both sides of the lower end of the lever
Is fitted by pushing the leg pieces 8.8 apart, the magnet lever 3 can swing up and down between the leg pieces 8.8 about the pivots 4.

When the magnet holder 7 is mounted at an appropriate position in the main body case 10, the stand leg pieces 8
As shown in the figure, the groove is formed in the groove 9 formed on the inner wall surface of the case, and thereafter, the movement of the fulcrum, that is, the deformation of the fulcrum is restricted by the groove.

[0016]

In FIG. 2, when the magnet lever 3 is pushed up by the water flowing from the water inlet 11 side, the magnet 2 attached to the tip of the magnet lever 3 approaches the reed switch 1, and the magnet 2 The reed switch 1 is turned on.

When the water supply is stopped in this state, the pushing up of the magnet lever 3 becomes zero, so that the magnet lever 3 descends by its own weight and turns off again.

The on / off operation makes it possible to control the combustion of the water heater.

In the product of the present invention, the switch is turned on when the water flow rate is within 3.5 liters / minute (when the water flow is increased), and is turned off when the water flow rate is 2.0 liters / minute or more (when the water flow is lowered).

Therefore, when the amount of water is 0 to 2 liters / minute, the switch is turned off, and the combustion does not occur.

Now, the amount of water is Q, the diameter of the flow control hole at the water inlet is d, the weight of the entire magnet lever is W, the length of the arm of the center of gravity of the magnet lever is L from the pivot axis, and the angle of the magnet lever when the flow rate is 0 is θn. The angle of the magnet lever is θf.

The flow rate at which the reed switch is turned on is represented by Qn, and the flow rate at which the reed switch is turned off is represented by Qf, which is expressed as follows: Qn = f (WLdθn)

W. d. As θn increases, Qn increases. (However, θ
n <90 degrees) Qf = f (WLd.theta.f) d. As θf increases, θf increases. As L increases, θf decreases.

In the present invention, the magnet lever is made of resin to reduce the weight of the entire magnet lever including the magnet and the like as much as possible. However, when the weight becomes small, there is a limit in adjusting the flow rate control hole diameter d at the water inlet to make the working flow rate the target flow rate. Therefore, the weight plate 6 is provided on the magnet lever so that the working flow rate becomes the target flow rate. Like that.

Further, after the magnet holder 7 is assembled into the main body case 10 by forcible press-fitting, the pivot portion is deformed due to aging, heat change, and the like. . This regulating means is shown in FIG.
Is described as follows.

A = the inner dimension of the fulcrum of the magnet lever 3 E = the outer dimension of the fulcrum of the magnet lever 3 D = the inner dimension of the magnet holder leg F = the outer dimension of the magnet holder leg B = the inner dimension of the groove of the main body case C = If the outer dimension of the groove of the main body case is A <B-0.2 mm, A <D-0.2 mm, it is possible to prevent the magnet holder from bending inward after press-fitting and prevent malfunction. .

Even if the leg of the magnet holder is opened outward and the dimension D is to be increased, the magnet lever is prevented from coming off because it is restricted by the groove of the main body case.

[0028]

[Effects of the Invention] Since the present invention is constructed as described above, the magnet lever, the holder for mounting the magnet lever, the pivot pins, and the like are all formed of metal products and assembled using screws. The number of parts is smaller, the production and assembly is very simple, and it is possible to provide an inexpensive one.In addition, the magnet lever, including the magnet, is lightweight and compact, but also incorporates a mass plate that doubles as a weight. It is possible to easily and reliably adjust the operating flow rate of the water flow switch to the target flow rate, and it is easy to assemble the magnet holder by forcible press-fitting into the main body case. This prevents the magnet lever from coming off due to the water hammer phenomenon, and also causes the stand legs of the magnet holder to bend inward. The malfunction becomes possible to regulate the groove portion of the body case, it is possible to prevent these inflection utmost.

[0029]

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a conventional water flow switch.

FIG. 2 is a vertical sectional side view showing an example of the water flow switch according to the present invention.

FIG. 3 is an enlarged cross-sectional view illustrating a main part of the water flow switch according to the present invention, which restricts deformation of a fulcrum of a magnet lever;

FIG. 4 is a side view of a magnet and a lever.

FIG. 5 is a sectional view taken along line AA in FIG. 4;

FIG. 6 is a sectional view taken along line BB in FIG. 4;

FIG. 7 is an exploded perspective view of the water flow switch according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reed switch 2 Magnet 3 Magnet lever 4 Axis 5 Magnet insertion part 6 Plate 7 Magnet holder 8 Stand leg piece 9 Groove 10 Body case 11 Water inlet 12 Water outlet 13 Stopper

Claims (1)

(57) [Scope of request for utility model registration] A lever (3) having a magnet body (2) mounted inside a main body case (10) so as to correspond to a reed switch (1) fixed at a fixed position on the outer surface of the main body case (10). ) Is swingably provided, and when the lever is pushed to the upstream side by water flow, the magnet body (2) approaches the reed switch (1) and the reed switch is turned on by magnetic force (1), and when water flow is stopped. A water flow switch which is turned off by its own weight;
Are integrally formed by resin formation with a lever portion (3a) having a pivot (4) protruding on both left and right sides, and a magnet portion (3b) having a magnet body (2) fitted in a magnet fitting portion (5). At the same time, a plate (6) having a mass also serving as a balance weight is provided in the open part of the magnet fitting part (5) of the magnet part (3b) in a plug-in manner, and a ring body is provided in the main body case (10). The magnet holder (7) of a resin molded product made of is fixed by press-fitting, and the stand leg (8) of the magnet holder (7) is inserted into the groove (9) formed on the inner surface of the main body case (10). Fitted and magnet lever (3) on stand leg (8)
A water flow switch characterized in that the pivot (4) is pivotally supported in a concave-convex fitting manner.