JPH07302525A - Float switch - Google Patents

Abstract

PURPOSE:To provide a float switch which is firm and easy to be assembled. CONSTITUTION:A water-proof switch is used as a switchgear means to be set in a float switch 10 and thus no member such as a partitioning plate, etc., to protect a switch 16 from humidity is needed and a push button 16b of the switch 16 is directly pushed by a shaft 14 set in a water receiving tank 40. With this structure, the number of the parts can be lessened and cost can be down and at the same time, the assembly of the switch becomes easy. Also, since the structure is simplified, troubles hardly occur and the switch becomes firm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a float switch which detects a change in the liquid surface position and turns the switch on and off when the liquid surface reaches a predetermined position. Regarding a float switch that turns on and off.

[0002]

2. Description of the Related Art For example, a float switch 100 as shown in FIG. 6 is widely used as a device for detecting the water level in a water tank installed on the roof of a building.
There is. Since the float switch 100 is used in a high humidity environment such as in a water tank, the switch 1
In order to prevent corrosion of the switching contacts (not shown) in 02, it is necessary to keep the switch 102 out of contact with the moist air in the water tank. Therefore, in the conventionally used float switch 102, as shown in the figure, the partition plate 106 is interposed between the switch 102 and the shaft 104 that turns the switch 102 on and off by vertical movement, whereby the switch 102 is installed. The inside of the float switch 100 and the water tank side where the shaft 104 is arranged are partitioned off to prevent corrosion of the contacts of the switch 102.

[0003]

However, with such a structure, like the members such as the partition plate 106,
Since a member for maintaining the watertightness and airtightness is required, the number of parts and the number of assembling steps increase, and the structure and assembling work become complicated. Therefore, the manufacturing cost becomes high.

Further, the switch 104 is provided by the shaft 104.
When turning on and off 2, the partition plate 106 interposed between the support members 108 and 110 must be deformed, and the partition plate 106 is damaged due to long-term use, the switch 102 corrodes, and the float switch 100 operates normally. There is also a risk that it will stop working.

The present invention, which has been made in view of the above problems, provides a float switch in which the switch and the pressing portion for pushing the switch can be easily positioned and easily assembled, and the structure is simple and robust. The purpose is to

[0006]

SUMMARY OF THE INVENTION The present invention for achieving the above object includes a float that moves up and down as the liquid surface position changes,
A movable member that moves up and down together with the float, a support member that holds the movable member so as to move up and down, and a guide portion that is open at both ends, and the support member that projects from one opening portion of the guide portion. A waterproof switch having an opening / closing contact directly pressed by a pressing portion formed at one end of the movable means,
A float switch having a holding member which is attached to the support member and protects the waterproof switch, wherein a fitting recess is formed in the waterproof switch, and the fitting recess is fitted to open and close a contact of the waterproof switch. The float switch is characterized in that a switch holding portion for positioning the pressing portion on a vertical movement path and holding the waterproof switch by cooperation with the holding member is formed on the support member.

[0007]

When the liquid surface position rises, the movable means rises along with the float. When the movable means rises, one end of the movable means projects from one opening of the support member and directly presses the opening / closing contact of the switch sandwiched between the support member and the holding member. As a result, the switching contact is closed, and the switch is turned on.

[0008]

Embodiments of the float switch according to the present invention will now be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a float switch of this embodiment that detects the water level in a water tank installed on the rooftop of a building and operates or stops various devices such as an alarm device. FIG. 2 is a perspective view showing a protruding portion on which the switch is mounted.

As shown in FIG. 1, the float switch 10 is generally provided with a shaft (movable means) having a float 12 which moves up and down in response to a vertical movement of a water level in a water receiving tank (not shown). 14, a switch (waterproof switch) 16 that is turned on and off by the vertical movement of the shaft 14,
A lower cover (support member) 18 that supports the shaft 14 and the switch 16 and an upper cover (holding member) 20 that holds the switch 16 by the lower cover 18 are provided.

Of these, the lower cover 18 has two through holes penetrating the upper and lower surfaces thereof, and one first through hole 22a has a passage portion 24a communicating with the first through hole 22a.
A cap 24 having (guide) is fitted. A guide pipe 26 having an inner pipe passage 26a communicating with the passage portion 24a is attached to the cap 24. The other second through hole 22b is a through hole for passing the cord 28 extending from the switch 16 described later.

In the passage G formed by the cap 24 and the guide pipe 26, the shaft 14 which is vertically movable with respect to the lower cover 18 is fitted and inserted. Therefore,
When the shaft 14 rises, the pressing portion 14a formed at the upper end thereof projects from the first through hole 22a to the upper surface side. The float 12 is attached to the lower end side of the shaft 14 by a push nut 30. This float 12
When the float switch 10 is installed in the water receiving tank, it is arranged so as to float near the water surface. Therefore, if the water level in the water tank changes, the float 12
As the shaft moves up and down, the shaft 14 integrated with the float 12 also moves up and down.

On the contrary, a ring 32 is attached to the upper end side of the shaft 14. When the shaft 14 moves downward, the ring 32 comes into contact with the upper end portion of the cap 24 attached to the lower cover 18, which limits the descending range of the shaft 14. Therefore, even if the water level in the water tank drops significantly,
The shaft 14 does not fall off the guide pipe 26.

Further, on the upper surface side of the lower cover 18, a projection portion (switch holding portion) 34 for holding the switch 16 is formed. As shown in FIG. 2A, the protrusion 34 is composed of two protrusions on the left and right sides.
34b is a recess 16a formed below the switch 16.
And a pair of outer peripheral protrusions 38a and 38b that come into contact with both sides of the switch 16. Therefore, the concave portion of the switch 16 is replaced by the central convex portion 36.
2B, the switch 16 has a central convex portion 36 and an outer peripheral convex portion 38, as shown in FIG. 2B.
It is held in a state of being sandwiched between a and 38b, as shown in FIG.
The front-back direction FB or the left-right direction LR, which is perpendicular to the moving direction of the shaft 14 indicated by the arrows in (A) to (C).
Be positioned about.

The switch 1 positioned in this way
Reference numeral 6 is a so-called waterproof switch in which a switch 16 is turned on by closing a switching contact (not shown) when the push button 16b is pressed. The push button 16b of the switch 16 is a shaft shown by a chain double-dashed line in FIG. Are arranged so as to be located on the movement route R of. Therefore, when the shaft 14 rises, the switch 16 is pressed by the pressing portion 14a.
The push button 16b is pressed and the switch 16 is turned on. On the other hand, when the shaft 14 descends from this state, the pressing portion 14a of the shaft separates from the push button 16b, so that the switch 16 is turned off.

This waterproof switch has a structure for preventing outside air from entering the inside of the switch, and is excellent in immersion resistance and drip resistance. Therefore, even when used in a high humidity environment such as in a water receiving tank, the switching contacts inside the switch 16 are not corroded. For this reason, the float switch 10 of this embodiment does not require a member such as a partition plate for isolating the inside of the cover in which the switch 16 is installed from the high humidity environment in the water receiving tank. Therefore, the switch 14 can be turned on / off by directly pushing the push button 16b of the switch 16 with the shaft 14. Further, by reducing the number of parts, cost reduction, simplification of structure, and quick assembly can be realized.

As the switch, not only a normally open type switch but also a normally closed type switch may be installed. For example, a lighting lamp (not shown) indicates that the water level in the water receiving tank is normal. In the case of recognition, it is preferable to use a normally closed switch. In this case, when the opening / closing contact is opened by the raised shaft 14 and the switch is turned off, the lamp is turned off.

Further, an upper cover 20 is attached to the lower cover 18 by screw connection. As illustrated, when the upper cover 20 is screwed into the lower cover 18, the switch 16 is sandwiched between the protrusion of the lower cover 18 and the upper cover 20. As a result, the switch 16 is positioned not only in the front-rear and left-right directions FB and LR but also in the up-down direction. Thus, the float switch 10 of the embodiment
Then, the switch 16 can be positioned at the same time when the upper cover 20 is attached to the lower cover 18, and the float switch can be assembled quickly and reliably with a small number of steps.

Next, the operation of the float switch having such a configuration will be described. In FIG. 3, when the water level W in the water receiving tank 40 rises, the shaft 14 having the float 12 rises accordingly. As shown in FIG. 1, the shaft 14 is inserted into a passage G communicating with the first through hole 22a of the lower cover 18, and when pushed upward, the pressing portion 14a projects upward from the through hole 22a. After that, when the shaft 14 is further raised, the push portion 16a of the shaft 14 directly pushes the push button 16b of the switch 16 to turn on the switch 16. A signal is generated when the switch 16 is turned on, and the signal is sent to a device such as a control device (not shown) connected thereto.

Thus, the float switch 1 of the embodiment
0, the switch 16 is directly sandwiched by the upper and lower covers 18 and 20 to be positioned, and thus the push button 16b
Is positioned at the vertically moving position of the pressing portion 14a, whereby the push button 16b is directly pressed by the pressing portion 14a to operate the switch 16. Therefore, the float switch can be configured with a small number of parts. Also, by simplifying the structure, cost reduction and easy assembly are realized. Furthermore, if the structure is simple, it is possible to prevent failures and the like, and it can be said that the structure is robust.

The float switch of the present embodiment is for explaining the contents of the present invention more clearly, and is not for limiting the technical scope. Therefore, various modifications can be made without departing from the spirit of the present invention. For example, the mounting structure of the lower cover 18 and the upper cover 20 is a screw type in the above embodiment, but for example, as shown in FIG. 4, a hook 50 for hooking is formed on the upper cover 20. At the same time, a hook portion 52 for hooking the hook 50 may be formed on the lower cover 18, and both covers 18, 20 may be attached by engaging the hook 50 and the hook portion 52. Of course, the hook may be formed on the lower cover and the hook portion may be formed on the upper cover.

Further, the float switch 10 of the present embodiment.
Is a structure in which only a switch for turning on and off a signal is installed inside the cover, but it is not a structure applied only to the float switch having such a structure, and for example, as shown in FIG. In addition to the switch 16, it can be adopted as a structure of a float switch provided with a horn 60 that starts to ring when the switch 16 is turned on.

[0022]

As described above, according to the present invention, since the number of parts of the float switch is reduced, the structure of the float switch can be made simple and robust. Further, the present invention has a structure in which the waterproof switch and the movable means are installed on the same member, and since the switch is held at the same time when the holding member is attached to the support member, the float is extremely quick and easy. The switch can be assembled.

Further, the push button of the waterproof switch is directly pushed by one end of the movable means projecting from one opening of the through hole formed in the support member, and another member is interposed therebetween. Since it does not have such a structure, the switch can be turned on and off more reliably.

[Brief description of drawings]

FIG. 1 is a sectional view showing a float switch of an embodiment.

2A is a perspective view showing a protruding portion of a lower cover on which a switch is mounted, FIG. 2B is a sectional view showing a BB section in FIG. 2A, and FIG. Is Figure 2
It is sectional drawing which shows CC cross section in (C).

FIG. 3 is an external view showing a state in which the float switch of the embodiment is attached to the water receiving tank.

FIG. 4 is a side view showing another mode of the engaging portions of the upper and lower covers of the float switch of the embodiment.

FIG. 5 is a side sectional view showing another embodiment of the float switch according to the present invention.

FIG. 6 is a side sectional view showing a schematic structure of a conventional float switch.

[Explanation of symbols]

 10 ... Float switch, 12 ... Float, 14 ... Shaft (movable means), 16 ... Switch (waterproof switch), 18 ... Lower cover (supporting member), 20 ... Upper cover (holding member), 32 ... Ring, 34 ... Protrusion (Switch holding part), G ... Passage (guide part).

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[Procedure amendment]

[Submission date] July 6, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

When the liquid surface position rises, the movable means rises along with the float. When the movable means rises, one end of the movable means projects from one opening of the support member and directly presses the opening / closing contact of the switch sandwiched between the support member and the holding member. As a result, the switching contact is closed, and the switch is turned on. When assembling this float switch,
A switch holder with a water switch mating recess formed in the support member.
Open / close contact of waterproof switch is possible by simply fitting it to the holding part
It is possible to position the pressing part of the moving means on the vertical movement path.
Wear. If a holding member is attached to the support member,
A waterproof switch is provided between the holding member and the switch holding portion of the supporting member.
The switch is clamped to position the waterproof switch in the vertical direction.
Will also be done.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

[0022]

As described above, according to the present invention, since the number of parts of the float switch is reduced, the structure of the float switch can be made simple and robust. Further, the present invention has a structure in which the waterproof switch and the movable means are installed on the same member, and the switch is positioned and held at the same time when the holding member is attached to the support member, which is extremely quick and Float switch can be easily assembled.

Claims (1)

[Claims] 1. A float that moves up and down in accordance with a change in the liquid surface position, a movable means that moves up and down together with the float, and a guide portion that holds the movable means up and down and is open at both ends. A formed support member, a waterproof switch having an opening / closing contact that is directly opened / closed by a pressing portion formed at one end of the movable means projecting from one opening of the guide portion, and the waterproof attached to the supporting member. A float switch having a holding member for protecting the switch, wherein a fitting recess is formed in the waterproof switch, and the opening / closing contact of the waterproof switch is fitted on the fitting recess on the vertical movement path of the pressing part. The float switch is characterized in that a switch holding portion for holding the waterproof switch is formed on the supporting member by positioning the waterproof switch in cooperation with the holding member.