JP2913458B2 - Liquid pressure switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a fluid pressure switch and, more particularly, relates to a liquid pressure switch for by detecting the pressure of the liquid flow path to control the operation of the liquid pressure device such as a pump is there.

[0002]

2. Description of the Related Art A conventional liquid pressure switch is generally provided with a pressure plate which advances and retreats in a direction perpendicular to the direction of piping, and adjusts the repulsive force of this pressure plate with a spring, and operates according to the advance and retreat position of the pressure plate. This is a structure in which a predetermined pressure is detected by a switch.

[0003]

However, the conventional method apparatus as described above has the following problems. (A) due to the forward and backward direction of the pressure plate is perpendicular to the moving direction of the direction, that the liquid piping, a portion of liquid remaining in the vicinity of the pressure plate tends to occur. Therefore, especially when the liquid contains solids and dirt such as sand, these may be clogged in the stagnation portion, making the pressure plate difficult to move, and the operation of the liquid pressure switch may become unstable or not operate. So
It could not be used to detect the pressure of such liquids . (B) Due to the structure in which the pressure plate moves forward and backward at right angles to the pipe, the switch portion protrudes from the pipe. Therefore, it is likely to be a hindrance in various operations near the liquid pressure switch, which is not preferable in terms of design.

[0004]

The object of the present invention is to solve the above problems,
The pressure of the liquid operated by detecting, for example, O of the liquid pressurizing device
In liquid pressure switches that perform N / OFF control, etc., where there is no liquid stagnation near the switch to prevent solids such as sand and dirt from clogging, and to detect the pressure of the liquid that contains these However, it is an object to provide a liquid pressure switch that operates stably. It is another object of the present invention to provide a liquid pressure switch which does not hinder various operations in the vicinity by reducing the width of the switch portion protruding from the piping.

[0005]

Means for Achieving the Object Means of the present invention taken to achieve the above object are as follows. In the first means, a switch actuated by the pressure fluctuations of the liquid flowing through the pipe, and the casing, Ri Oh provided on the case, the introduction-side joint and the discharge-side joint are connected to the pipe A check valve provided on the introduction-side joint side, an expansion-contraction body provided in communication with the introduction-side joint and the discharge-side coupling, and having an expansion / contraction property; Have been
A switch operated by expansion and contraction of the expansion and contraction body caused by pressure fluctuation of the liquid in the expansion and contraction body.

According to a second aspect of the present invention, the switch has a movable terminal plate and a deformation adjusting tool capable of adjusting a maximum deformation amount of the movable terminal plate . Departure
3 is a liquid pressure switch according to the present invention.

In the third invention, there is provided a pressure supply means which operates after or simultaneously with the operation of the check valve to prevent a decrease in liquid pressure inside the pipe due to a leak pressure and maintain the pressure. A liquid pressure switch according to the first or second invention, characterized in that:

The material of the expandable and contractible body is not particularly limited as long as it has a sufficient expansion and contraction ability, and is, for example, rubber or synthetic resin, or a composite material of rubber and synthetic resin. Switch, for example, those ON · OFF operation is performed by the contact and separation of the contacts, a movable contact provided in the deformable member which is deformed for example by the displacement of the expansion and contraction body <br/>, Rise
When the contracted body expands, the deformable member is deformed so that the fixed contact and the movable contact come into contact with or separate from each other. Further, the movable contact can be directly provided on the outer surface of the expansion / contraction body . The pressure supplied to the pressure supply means may be a gas pressure such as an air pressure or a hydraulic pressure such as a water pressure.

[0009]

The liquid pressure switch is attached to a pipe such as a water pipe. The expansion and contraction body is disposed in the path of the pipe. The switch is
For example, it is ON, the liquid pressurizing device is in an operating state, and water flows at substantially constant pressure inside the pipe. When the water stop valve is closed in this state, the water pressure in the piping rises instantaneously,
As a result, the expansion / contraction body expands, and the switch senses this and turns off. For example, the liquid pressurizing device stops and the flow of water stops.

[0010] In addition, it is provided with the check valve, in the pipe
When the water pressure rises, the check valve operates almost simultaneously. Water pressure inside the pipe containing the expansion and contraction thereof by the action of the check valve is maintained, Rise
The compact remains expanded. Therefore, the switch is also OFF
Stabilizes as it is.

The movable terminal plate which is deformed by the expansion
Equipped with a deformation adjuster capable of adjusting the maximum deformation amount
The movable end when the displacement of the expansion and contraction body is too large
The breakage of the child board can be prevented.

In the case where the pressure supply means which operates after or simultaneously with the operation of the check valve is provided, the pressure can be supplied to the inside of the pipe including the expansion and contraction body. Liquid inside the piping,
The pressure can be maintained by preventing a decrease in body pressure.
According to this, the expansion and contraction body can be maintained as it is expanded, and the state of the switch can be maintained as it is.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the embodiments shown in the drawings. FIG. 1 shows an embodiment of a liquid pressure switch according to the present invention, in which the expansion and contraction body is reduced and the switch is connected, and FIG. 2 is a state where the expansion and contraction body is expanded and the switch is turned off. FIG.

Reference numeral S denotes a liquid pressure switch having a rectangular parallelepiped case 1. At both ends in the length direction of the case 1, a tubular introduction-side joint 2 and a discharge-side joint 3 are attached through the end walls 11 and 12. The outer surfaces of the inlet-side joint 2 and the discharge-side joint 3 near the outer ends are provided with locking strips 2 over the entire circumference.
1, 31 are provided. An air pump 9 (shown in FIG. 3, omitted from FIGS. 1 and 2) as pressure supply means is connected to the discharge side joint 3. The air pump 9 is stopped when the check valve 4 described below is not operating, and is controlled so as to operate at the same time as the check valve 4 operates.

A check valve 4 (a check valve) is provided at an end of the inlet side joint 2 on the inner side of the case 1. Here, the structure of the check valve 4 will be described. The check valve 4 has a valve seat 41 provided inside the introduction-side joint 2. Valve seat 41
Has a through hole 4 having a diameter of about 1/2 of the inner diameter of the pipe.
2 are provided. An end wall 43 is provided at the end of the introduction-side joint 2 on the case 1 side, and the end wall 43 is provided with through holes 44 having slightly smaller diameters at two places.

The end wall 43, the valve seat 41 and the inlet-side joint 2
The portion surrounded by the peripheral wall of the valve body 45 is a valve chamber 45, in which the valve body 4 attached to the distal end of the guide pin 46 is provided.
7 are accommodated. The valve body 47 has a flat cylindrical shape and can close the through hole 42 by contacting the valve seat 41. The guide pin 46 is provided so as to slide through the end wall 43, and a coil spring 48 is provided on the inner surface side of the valve body 47 and the end wall 43.

Between the inner end of the inlet-side joint 2 and the inner end of the discharge-side joint 3, an expansion / contraction body 5 made of a rubber tube, which is an expansion / contraction body , is attached. The amount of displacement of the expansion / contraction body 5, that is, the difference between when it is expanded and when it is contracted, can be appropriately set by changing the degree of flexibility and thickness of the material. Case 1
A switch 6 is provided in the vicinity of the expansion / contraction body 5.

The switch 6 has a fixed terminal plate 61. The fixed terminal plate 61 is provided near the discharge side joint 3, and a contact 62 is provided at an end thereof. A movable terminal plate 63 having flexibility is provided in the vicinity of the expansion / contraction body 5. A contact 64 is provided at the tip of the movable terminal plate 63. The contact 62 and the contact 64 are provided so as to face each other.

A spacer 65 for assisting the operation of the movable terminal plate 63 is provided on the inner surface of a substantially intermediate portion of the movable terminal plate 63.
Is attached. An adjustment screw 66 is screwed through substantially the center of the side wall 13 of the case 1. The screw portion 67 of the adjustment screw 66 is located at an intermediate portion between the side wall 13 and the movable terminal plate 63. On the outer surface side of the movable terminal plate 63, a stopper pin 68 is provided so that the distal end thereof is opposed to the distal end of the screw portion 67 at a slight interval. A coil spring 69 is fitted on the stopper pin 68 and the screw portion 67 so as to urge the movable terminal plate 63 toward the expansion / contraction body 5 side.

The maximum amount of deformation of the movable terminal plate 63 can be adjusted by turning the adjusting screw 66 to adjust the contact point between the tip of the screw portion 67 and the tip of the stopper pin 68. In this case, the movable terminal plate 63 is prevented from being damaged when the displacement amount is too large.

(Operation) FIG. 3 is an explanatory diagram showing an example of a use state of the liquid pressure switch. The operation of the present embodiment will be described with reference to FIGS. The liquid pressure switch S has a drain pipe 71 of a submersible pump 7 as a liquid pressurizing device connected to the inlet-side joint 2, and a switch 6 attached to a power cord 72 in series. A water supply pipe 73 is connected to the discharge side joint 3 of the liquid pressure switch S.
Is provided.

When the power cord 72 is connected to a power source, the submersible pump 7 operates. When the submersible pump 7 draws water and passes through the expansion / contraction body 5, the pressure in the pipe is almost constant, and the expansion / contraction body 5 is in a contracted state (the contracted state is a normal state).
Thus, the contacts 62 and 64 of the switch 6 are in contact and in the ON state. Thus, the submersible pump 7 is continuously operated. Also, even if the water is rich in solids such as sand and dirt,
Since the solid material easily passes through the through holes 42 and 44 and hardly causes a stagnant portion, the operation can be performed without any trouble.

When the stop valve 8 is stopped, the water supply pipe 73 is stopped.
The pressure inside rises instantaneously, whereby the expansion / contraction body 5 expands, and the check valve 4 operates almost at the same time. At the same time, the air pump 9 operates. Movable terminal plate 6 of switch 6
3 is bent outward due to the expansion displacement of the expansion body 5, and the contact 6
When the switches 2 and 64 are separated from each other, the switch 6 is turned off, and the submersible pump 7 stops.

Since air is sent into the water supply pipe 73 including the expansion / contraction body 5 by the air pump 9, even if water leaks from the water stop valve 8 or the check valve 4, the water pressure inside the water supply pipe 73 is reduced. Prevent and maintain pressure. According to this, the expansion / contraction body 5 can be maintained in an expanded state,
The OFF state of the switch 6 can be maintained as it is.

Then, when the water stop valve 8 is opened, the water pressure in the water supply pipe 73 is released and lowered, the check valve 4 is released, and the expansion / contraction body 5 contracts as before. Note that the air pump 9 stops. As a result, the switch 6 is turned on, the submersible pump 7 operates, and water is supplied from the water supply pipe 73. The present invention is not limited to the illustrated embodiment, but can be variously modified within the scope of the claims.

[0026]

(A) If a liquid pressure switch is used as a switch for a pump by being attached to a water supply pipe, for example, the water is stopped at the water supply side to expand the expansion and contraction body and use the displacement. Switch operation. And since the expansion and contraction body is usually arranged in parallel with the path of a pipe such as a water supply pipe, a stagnation portion of the liquid is hardly generated, and a solid matter is hardly clogged even if the liquid contains a large amount of fixed matter. Therefore, it can be used as a liquid pressure switch when handling such a liquid .

(B) Since the expanding and contracting body is arranged in parallel with a pipe such as a water supply pipe, unlike a conventional switch having a pressure plate which advances and retreats in a direction perpendicular to the direction of the pipe, the projecting width from the pipe is different. Can be reduced. Therefore, it is hard to hinder various operations, and damage to the switch due to contact or the like can be prevented.

[0028] is provided with the (c) check valve, in the pipe
As the liquid pressure increases, the check valve operates almost simultaneously. Liquid pressure within the pipe containing the expansion and contraction thereof by the action of the check valve is maintained, deflating member for actuating the switch will remain inflated, it is possible to stabilize the operation state of the switch.

(D) The switch has a movable terminal plate and is movable.
Equipped with a deformation adjuster that can adjust the maximum deformation of the terminal board
The displacement of the expansion / contraction body is too large
Of the movable terminal plate can be prevented.

[0030] (e) the check valve is in the one pressure supply means operative after or simultaneously operated is provided, inflation and deflation
Since pressure can be supplied inside the piping including the body ,
Even if the pressure is leaked due to water leakage or the like, it is possible to prevent the liquid pressure inside the pipe from decreasing and maintain the pressure. According to this, the state of the switch can be maintained as it is while the expandable body is expanded, and the operation of the liquid pressure switch can be further stabilized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a liquid pressure switch according to the present invention, in a state where an expandable and contractible body is reduced and a switch is connected.

FIG. 2 is a cross-sectional view showing a state where a switch is turned off due to expansion of an expansion / contraction body.

FIG. 3 is an explanatory diagram illustrating an example of a use state of a liquid pressure switch.

[Explanation of symbols]

S liquid pressure switch 1 Case 11, 12 End wall 2 Inlet side joint 21 Locking line 3 Discharge side joint 31 Locking line 4 Check valve 41 Valve seat 42 Through hole 43 End wall 44 Through hole 45 Valve chamber 46 Guide pin 47 Valve body 48 Coil spring 5 Expansion / contraction body 6 Switch 61 Fixed terminal plate 62 Contact 63 Movable terminal plate 64 Contact 65 Spacer 66 Adjustment screw 67 Screw part 68 Stopper pin 69 Coil spring 7 Underwater pump 71 Drain pipe 72 Power cord 73 Water supply pipe 8 Water stop Valve 9 air pump

Claims (3)

(57) [Claims] 1. A switch actuated by pressure fluctuations of the liquid flowing in the pipe, a casing (1), Ri Oh being arranged in the casing (1), guide <br/> connected to the pipe Inlet-side joint (2) and outlet-side joint (3), check valve (4) provided on the inlet-side joint (2) side, inlet-side joint (2) and outlet-side joint (3) The expansion and contraction body (5) having expansion and contraction properties is attached to the expansion and contraction body (5). A liquid pressure switch, comprising: a switch (6) operated by expansion and contraction of the expansion / contraction body (5). 2. The switch (6) has a movable terminal plate (63),
The liquid pressure switch according to claim 1, further comprising a deformation adjusting tool capable of adjusting a maximum deformation amount of the movable terminal plate (63). 3. A pressure supply means which operates after or simultaneously with the operation of the check valve (4) to prevent a decrease in liquid pressure inside the pipe due to leak pressure and maintain the pressure. The liquid pressure switch according to claim 1 or 2.