JPH0545718Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a door opening/closing confirmation device that can check the open/closed state of a door in furniture or other equipment having an opening/closing door.

(Prior art) Conventionally, a magnetic catch generally has a structure in which a permanent magnet has magnetic poles on both end faces, and a yoke piece made of iron or the like is provided on each of the magnetic pole faces. It is designed to attract and hold attached armature pieces (movable magnetic material pieces) such as iron pieces.

(Problem that the invention aims to solve) In this case, the conventional magnetic catch only has the function of locking the door in the closed state, and the magnetic catch itself can directly drive the reed switch. This was not thought of at all. Therefore, in order to reliably detect the closed state of doors of furniture, copying machines, etc., it was necessary to provide a detection means such as a limit switch, a micro switch, or a combination of a permanent magnet and a reed switch in addition to the magnetic catch. . For this reason, not only does the cost increase due to the provision of another detection means, but
There were disadvantages such as the need to provide a separate space for installing these detection means.

On the other hand, as shown in FIG.
The proximity of the magnetic object to be detected 31 is detected by combining a pair of detection permanent magnets 25 and a pair of auxiliary permanent magnets 26 having magnetic poles oriented to cancel the magnetic flux density due to the magnetic poles of the pair of detection permanent magnets 25. A magnetic type proximity switch is known (Jikkoaki).
49-46060). In the figure, 21 is a box, 23 is a lead wire, 30 is a leaf spring, and 29 is a reed switch mounting frame.

This magnetic type proximity switch shown in FIG.
The magnetic fields of the pair of auxiliary permanent magnets 26 are completely canceled out, and the reed switch 27 is turned off. Then, when the magnetic detected object 31 approaches the pair of detection permanent magnets 25, the magnetic resistance between the N and S poles on the upper surface of the pair of detection permanent magnets 25 decreases.
As a result, the magnetic flux density between the N and S poles of the pair of detection permanent magnets 25 on the reed switch 27 side increases, and the reed switch 27 is activated and turned on.

However, the configuration shown in Figure 12 is designed to function only as a proximity switch.
There is virtually no function as a magnetic catch. It is also conceivable to arrange a yoke piece such as an iron plate to function as a magnetic catch, but the pair of detection permanent magnets 25 are magnetized in the thickness direction (vertical direction), and magnetic poles are formed on the upper and lower end surfaces. Therefore, arranging yoke pieces on both sides of the detection permanent magnet 25 does not help improve the magnetic attraction force (the yoke pieces must be in contact with the magnetic poles of the permanent magnet).

(Means for solving the problem) The present inventor proposed that the magnetic flux density at the end face of the yoke of the magnetic catch changes depending on whether or not the magnetic material on the door side is attracted, and that the amount of change is sufficient to operate the reed switch. It was found that the size was large enough to allow

Therefore, in view of the above points, the present invention aims to provide a door opening/closing confirmation device that does not require a complicated magnetic circuit and can detect the opening/closing of a door using an extremely simple mechanism that combines a magnetic catch and a reed switch. That is.

The door opening/closing confirmation device of the present invention has a permanent magnet having magnetic poles formed on both end faces and yokes arranged respectively on both magnetic pole faces of the permanent magnet, and one longitudinal end face of each of the paired yokes. a magnetic catch that attracts the magnetic material on the door side, and a reed switch that faces the other longitudinal end face of each of the paired yokes or the transverse end face of each yoke, and each lead of the reed switch is connected to each other. The reed switch is arranged close to each end face in the longitudinal direction or each end face in the transverse direction, and is arranged in a direction relative to the arrangement direction of the yokes so as to detect changes in magnetic flux between the yokes corresponding to adsorption and detachment of the door-side magnetic body. The magnetic flux density exerted on the reed switch between each yoke when the door-side magnetic body is attracted is equal to or less than the open value of the reed switch, and when the door-side magnetic body is detached, each yoke is The magnetic flux density exerted on the reed switch between the yokes is set to be equal to or higher than the impression value of the reed switch.

(Function) The present invention is configured such that the magnetic flux density exerted on the reed switch of the yoke of the magnetic catch when the magnetic body on the door side is attracted is equal to or less than the open value of the reed switch, and is applied to the reed switch of the yoke when the magnetic body on the door side is detached. The magnetic flux density exerted on the reed switch is set to be higher than the reed switch's sensitivity value, and as a result, the reed switch is turned on when the door is opened and turned off when the door is closed. As a result, it is possible to realize the attraction and holding of the door by the magnetic catch as well as the detection of the open/closed state of the door with an extremely simple mechanism. In addition, in this invention, the positional relationship between the magnetic catch consisting of a permanent magnet and a yoke and the reed switch is fixed, so there is no need to move the permanent magnet, and a magnetic material such as an iron piece is attached to the door side. That's fine. Therefore, problems such as alignment between the magnetic poles of the permanent magnet and the reed switch, which are problems when attaching a permanent magnet to the door side, and damage when a shock is applied to the permanent magnet do not occur.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a door opening/closing confirmation device according to the present invention will now be described with reference to the drawings.

1 to 3 show a first embodiment of the present invention. In these figures, magnetic catch 1
In this example, yoke pieces 3 are arranged on both magnetic pole faces of a rectangular parallelepiped permanent magnet 2 having magnetic poles formed on both end faces in the thickness direction, and these pieces are provided in a resin case 4. The resin case 4 has a convex portion 6 that engages with the hole 5 of the yoke piece 3, thereby holding the yoke piece 3 so that it does not fall off. Further, the case 4 is integrally formed with a spring portion 7 that pushes up the bottom portion (longitudinal end surface) of the yoke piece 3.

On the other hand, the reed switch 10 is arranged on the bottom side of the magnetic catch 1 as shown in FIG. That is, the reed switch 10 closely opposes the longitudinal end surfaces of the pair of yoke pieces 3 (that is, the leads 10a and 10b of the reed switch 10 closely oppose each longitudinal end surface), and The angle θ that the center line A forms with the axial center line B of the magnetic catch 1 is 90°.
It is set to .

Note that an armature piece (movable magnetic piece) 8 such as a door-side iron piece is adapted to be attracted to the upper longitudinal end surface of the yoke piece 3.

The operating principle of the first embodiment of the present invention will be explained with reference to FIGS. 10 and 11. First, when the armature piece 8 on the door side is sufficiently separated from the pair of yoke pieces 3 as shown in FIG. 3
passing through the space from the tip surface of the yoke piece 3 to the other yoke piece 3 facing the S pole,
Further, it passes through the inside of the yoke piece 3 and returns to the S pole. As a result, a magnetic flux passing between the lower ends of the pair of yoke pieces 3 as shown by the dotted arrow acts on the reed switch 10, and the reed switch 10 is activated and turned on (the magnetic flux density is higher than that of the reed switch). It has more than impressive value.)

Furthermore, when the armature piece 8 on the door side is attracted to the upper end surface of the pair of yoke pieces 3 as shown in FIG. It passes through one yoke piece 3 that is in contact with the yoke piece 3, the armature piece 8 in the attracted state, and the other yoke piece 3 that is in contact with the S pole, and returns to the S pole.
As a result, the magnetic flux passing through the space between the pair of yoke pieces 3 becomes extremely small, and the reed switch 10
There is also extremely little magnetic flux acting on it. Therefore, the reed switch 10 does not operate and is turned off (the magnetic flux density becomes less than the open value of the reed switch), and the opening and closing of the door can be detected.

FIG. 4 shows the relationship between the distance x of the reed switch 10 from the longitudinal end face of the yoke and the magnetic flux density acting on the reed switch 10 when the angle θ is 90°. In this figure, the curve C is the magnetic flux density when the armature piece 8 is detached from the magnetic catch 1 as shown in Fig. 5A, and the curve D is the magnetic flux density when the armature piece 8 is attached to the magnetic catch 1 as shown in Fig. 5B. It shows the magnetic flux density when is attracted. Also,
Dotted line E is the emotional value of reed switch 10 Φ off → on
(In the case of 80G as an example), and the dotted line F shows the open value Φon→off (in the case of 60G as an example). The value of x at the intersection of the dotted line F and the curve D is x ₁ , and the value of x at the intersection of the dotted line E and the curve C is x ₂ .

From FIG. 4, when 0≦x< _x1 , the reed switch 10 is always on regardless of the state of the armature piece 8, and when _x2 <x, the reed switch 10 is always off, and when _x1 ≦x≦ _x2. At this time, the reed switch 10 is turned off when the armature piece 8 is attracted, and turned on when it is detached. That is, the distance x from the longitudinal end surface of the yoke on the bottom side of the magnetic catch shown in FIGS. 5A and 5B to the reed switch 10 is defined as x ₁ ≦x≦
When set to x ₂ , the reed switch 10 turns off in response to adsorption and detachment of the door side armature piece 8.
Turn on.

FIG. 6 shows a second embodiment of the invention. In this figure, a reed switch 10 is placed on the bottom side of the magnetic catch 1 as shown. That is, the reed switch 10 faces the longitudinal end surfaces of the pair of yoke pieces 3, and the angle θ formed by the axial center line A of the reed switch 10 with the axial center line B of the magnetic catch 1 is other than 90°. is set to the value of

Figure 7 shows the distance x defined in Figure 5 A and B above.
The relationship between the angle θ of the reed switch 10 and the magnetic flux density acting on the reed switch 10 when θ is 0 is shown. In this figure, curve G shows the magnetic flux density when the armature piece 8 is detached from the magnetic catch 1, and curve H shows the magnetic flux density when the armature piece 8 is attracted to the magnetic catch 1. From these curves G and H, the magnetic flux density is determined by the angle θ
It can be seen that as the angle becomes smaller than 90°, it decreases in a trigonometric manner. In addition, the dotted line I is the emotional value of reed switch 10 Φoff → on (for example, in the case of 80G)
, and the dotted line J indicates the open value Φon→off (as an example
60G). The value of θ at the intersection of dotted line I and curve G is θ ₁ , and the value of θ at the intersection of dotted line J and curve H is θ ₂ .

From FIG. 7, when 0≦θ<θ ₁ , the reed switch 10 is always off regardless of the state of the armature piece 8, and when θ ₂ <θ, the reed switch 10 is always on, and when θ ₁ ≦θ≦θ ₂ At this time, the reed switch 10 is turned off when the armature piece 8 is attracted, and turned on when it is detached. That is, as shown in FIG. 6, when the angle between the axial center line A of the reed switch 10 and the axial center line B of the magnetic catch 1 is θ, and the distance x is 0, θ ₁ ≦θ≦θ ₂ , the reed switch 10 is turned off and on in response to adsorption and detachment of the door side armature piece 8.

Now, in the arrangement shown in FIG. 6, the distance x can take values other than 0. Therefore, FIG. 8 shows the operating range in which the reed switch 10 turns off and on in response to the adsorption and detachment of the armature piece 8 by changing both the distance x and the angle θ. In FIG. 8, curve K is the open value curve when armature piece 8 is detached (the point where the magnetic flux density acting on reed switch 10 is 60 G with Φon → off as 60 G is plotted),
Curve L is the impression value curve when armature piece 8 is removed (Φ off → on is 80 G, and the point where the magnetic flux density acting on reed switch 10 is 80 G is plotted),
Curve M is an open value curve when armature piece 8 is attracted, and curve N is an impression value curve when armature piece 8 is attracted. Then, let the regions divided by each curve be P to T.

If the reed switch 10 is located in the region P of FIG. 8, it will be located above the curve M when the armature piece 8 is attracted, so the magnetic flux density will be less than the open value and the reed switch 10 will be off. However, even when the armature piece 8 is detached, it is above the curve K and is still off. Therefore, region P does not correspond to the movement of armature piece 8, and reed switch 10 is always off.

If the reed switch 10 is located in the region P, it will be located above the curve M when the armature piece 8 is attracted, so the magnetic flux density will be less than the open value and the reed switch 10 will be off. However, when the armature piece 8 is detached, the magnetic flux density does not reach the impression value above the curve L, so it is turned off. Therefore, region Q does not correspond to the movement of armature piece 8, and reed switch 10 is always off.

If the reed switch 10 is located in the region R, it will be located above the curve M when the armature piece 8 is attracted, so the magnetic flux density will be less than the open value and the reed switch 10 will be off. Also, armature piece 8
At the time of separation, the magnetic flux density reaches the emotional value below the curve L, so it is turned on. Therefore, region R turns off and on in response to adsorption and detachment of armature piece 8.

If the reed switch 10 is located in the region S, it will be located below the curve M even when the armature piece 8 is attracted, so the magnetic flux density will be greater than the open value and the reed switch 10 will remain on. Also, when the armature piece 8 is detached, it is below the curve L and is also turned on. Therefore, the region S does not correspond to the movement of the armature piece 8 and always corresponds to the reed switch 10.
is turned on.

If the reed switch 10 is located in the region T, the reed switch 10 is located below the curve N when the armature piece 8 is attracted, so the magnetic flux density is greater than the impression value and the reed switch 10 is on. Also, armature piece 8
At the time of separation, the magnetic flux density turns on below the curve L when it exceeds the impression value. Therefore, the region T does not correspond to the movement of the armature piece 8 and always corresponds to the reed switch 1.
0 is on.

From FIG. 8 above, it can be seen that the reed switch 10 attracts the armature piece 8 in the shaded area R in the figure.
It turned out that it turns off and on in response to the withdrawal action. In this case, if the angle θ is less than 5°, it is difficult to operate the reed switch 10 regardless of the distance x, and if the distance x is greater than 10 mm, it is difficult to operate the reed switch 10 regardless of the value of θ. It is. Therefore, it is recognized that the arrangement of the reed switch 10 is preferably set such that 5°≦θ≦90° and 0≦x≦10 mm.

FIG. 9 shows a third embodiment of the present invention. In this figure, the reed switch 10 is arranged on the side surface of the magnetic catch 1 opposite to the end surface of the yoke piece 3 in the lateral direction. Also in this case, the distance between the end surface of the yoke piece 3 in the short direction and the reed switch 10 is x,
If the angle formed by the axial center line of the reed switch 10 with respect to the center line along the short side of the yoke is θ, the relationship shown in FIG. 8 also holds true. Therefore, it is possible to find a region R in which the reed switch 10 turns off and on in response to the attraction and detachment of the armature piece 8.

Note that as long as the positional relationship between the reed switch and the magnetic catch is maintained constant, the reed switch may be integrated into the case of the magnetic catch or may be attached separately.

(Effect of the invention) As explained above, the door opening/closing confirmation device of the invention includes a permanent magnet with magnetic poles formed on both end faces and a yoke disposed on each of the magnetic pole faces of the permanent magnet. a magnetic catch that attracts the door-side magnetic body on one longitudinal end face of the yoke; and a magnetic catch that faces the other longitudinal end face of the yoke or the transverse end face of the yoke and attracts the door-side magnetic body. , a reed switch is arranged in a fixed positional relationship so as to detect a change in magnetic flux between the yokes corresponding to the detachment, and the magnetic flux density exerted on the reed switch of the yoke when the door-side magnetic body is attracted is determined by the reed switch. By setting the magnetic flux density that the yoke exerts on the reed switch when the door-side magnetic body is detached to be equal to or higher than the reed switch's opening value, the door can be adsorbed with an extremely simple and inexpensive mechanism. It is possible to hold the door and detect the opening and closing of the door.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view showing the first embodiment of the door opening/closing confirmation device according to the present invention, Fig. 2 is a sectional view of the same side, and Fig. 3 is a sectional view of the same side.
The figure is a bottom view of the same, Figure 4 is a graph showing the relationship between distance x and magnetic flux density acting on the reed switch when angle θ is 90°, Figure 5A is a side view showing the armature piece detached state, Fig. 5B is a side view showing the armature piece being attracted, Fig. 6 is a bottom view showing the second embodiment of the present invention, and Fig. 7 is the angle θ when the distance x is 0 and the magnetic flux acting on the reed switch. A graph showing the relationship with the density. Fig. 8 is a graph showing the reed switch's impression and open area by changing both the distance x and the angle θ. Fig. 9 is a cross section showing the third embodiment of the present invention. 10 is an explanatory diagram of the operation when the door side armature piece is sufficiently spaced in the first embodiment of the present invention, FIG. 11 is an explanatory diagram of the operation when the door side armature piece is attracted to the yoke piece, and FIG.
The figure is a sectional view showing a conventional magnetic proximity switch. 1...Magnetic catch, 2...Permanent magnet,
3...Yoke piece, 4...Resin case, 10...Reed switch.

Claims (1)

[Scope of Claim for Utility Model Registration] Comprising a permanent magnet with magnetic poles formed on both end faces and yokes disposed on both magnetic pole faces of the permanent magnet, one longitudinal end face of each of the paired yokes. A magnetic catch that attracts the magnetic material on the door side,
a reed switch that faces the other longitudinal end face of each yoke in the pair or the transverse end face of each yoke, and each lead of the reed switch is closely opposed to each longitudinal end face or each transverse end face, respectively. The reed switch is arranged in a fixed positional relationship non-parallel to the arrangement direction of the yokes so as to detect changes in magnetic flux between the yokes corresponding to adsorption and detachment of the door-side magnetic body, and The magnetic flux density exerted on the reed switch between each yoke when the side magnetic body is attracted is equal to or less than the open value of the reed switch, and the magnetic flux density exerted on the reed switch between each yoke when the door side magnetic body is detached is set to A door opening/closing confirmation device that is characterized by exceeding the emotional value of the switch.