JPH1167035A - Switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a switch high in durability and flexibility. SOLUTION: A ring-like magnet part 10 having the magnetic pole surface of an axial directional end surface is arranged in one end part in an about cylindrical main body part 3. A reed switch device 20, providing a longitudinal reed switch 21 in a pedestal part 11, is fitted, along the axial direction of the main body in the main body part 3. A moving body 30, thereon the reed switch 21 is formed insertably and about slender-bar-likely, is housed in the main body part 3 so that the tip part of the moving body 30 is movable from one end opening 2b of the main body 3 along an axial direction. A coil spring 29, for energizing the movable body 30 in its proceeding direction, is arranged between the movable body 30 and the pedestal part 11. A ring-like magnet 35 is fitted, in polarity reverse to that of the magnet part 10, to the moving body 30. When the movable body 30 is not moved, the magnet part 10 and the magnet 35 are overlapped to constitute a closed circuit to reduce the influence of magnetic force on the reed switch 21, thereby turning off the lead switch. When the moving body 30 is moved, the magnet part 10 and the magnet 35 are displaced, thereby turning on the reed switch 21 by the influence of the magnetic force of the magnet part 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch that opens and closes a reed switch when a moving body moves forward and backward.

[0002]

2. Description of the Related Art Conventionally, as this type of switch, for example, Japanese Patent Application Laid-Open No.
The configuration described in Japanese Patent Publication No. 187030 is known.

A switch described in Japanese Patent Application Laid-Open No. 62-122015 is a switch for opening and closing the contact portions in conjunction with the pressing operation of a steel ball as a sphere in a bottomed cylindrical metal cover. The body is slidably mounted. A return spring seat, which is supported by a seat provided on the plunger, is formed at the base end of the moving body, and the return spring is inserted into this portion. Form the bearing surface of the biasing spring of the contact piece, b
A locking step for receiving the movable contact piece in the contact type is formed. Further, a supporting portion for slidably supporting the movable contact piece is formed, the movable contact piece is supported on this portion, and a spring for urging is applied to the outer end side of the supporting portion from the base end side at the time of the a contact type. A removable locking member is provided for regulating the position of the movable contact piece to be biased and removing it in the case of the b-contact type. Also,
The movable contact piece and the a-contact type contact and separate from the outer surface, and the b-contact type separate from and from the inner surface of the plunger with the biasing spring seat for the b-contact type formed inside the return spring seat. An L-shaped pair of terminal plates is implanted at positions corresponding to each contact type so as to be selectable. Further, in the case of the a contact type, an urging spring is interposed between the seating surface of the urging spring of the movable contact piece of the moving unit and the movable contact piece supported by the support unit and received by the locking member. At the time of contact type, it is supported by the support of the moving part.
An urging spring is interposed between the movable contact piece received on the inner surface of the terminal plate having the shape and the seating surface of the urging spring in the case of the b-contact type of the terminal base.

[0004] However, Japanese Patent Application Laid-Open No.
The device described in Japanese Patent Publication No. 15 is designed to make the contact come and go by sliding movement of the moving body. Therefore, when a pressing operation is performed to further move the moving part after the contact comes into contact, the contact or the moving body, The terminal base may be damaged. In addition, contact damage of the contact portion due to contact and separation of the contact occurs, and the increase in durability is also restricted.

On the other hand, the switch described in Japanese Utility Model Laid-Open Publication No. 59-187030 has a movable contact movable along the axial direction of the main body at one end of a substantially cylindrical main body having both ends opened. There is provided a switch unit including a contact that is short-circuited and closed by the contact of the movable contact and a first coil spring that constantly urges the movable contact and separates the contact from the contact. A moving body having a housing for rotatably holding a steel ball at one end is slidably accommodated in the main body.
Then, the steel ball of the moving body is urged by the first coil spring in a direction protruding from the opening on the other end side of the main body to be housed movably. Further, a second coil spring having an urging force stronger than the urging force of the first coil spring is provided in the moving body, and the second coil spring is moved with the moving of the moving body in a direction in which the steel ball moves backward. An operator that moves by the urging force and moves the movable contact of the switch unit against the urging of the first coil spring is housed at the distal end. When the movable contact comes into contact with the contact and the movement is restricted, when the force for further moving the moving body is applied, the operator relatively moves against the urging force of the second coil spring. It is provided movably in the moving body so as to retreat into the body.

However, Japanese Utility Model Application Laid-Open No. 59-1870
The device described in Japanese Patent Publication No. 30 is operated even when a force to move the movable body is applied after the movable contact of the switch section and the contact abut upon the sliding movement of the movable body and the movement of the movable contact is regulated. Although the switch unit can be prevented from being damaged by the movement of the child, the movable range of the moving body can be set wide.
It is difficult to set the balance between the biasing forces of the coil springs and the second coil springs, resulting in a decrease in manufacturability and an increase in cost. The moving force of the moving body is changed by the biasing force of the second coil spring, and the movable body moves backward due to the biasing force of the second coil spring. The relationship between the moving distance and the closing of the switch section is different, and it is difficult to obtain highly accurate detection. Further, similar to the one described in Japanese Patent Application Laid-Open No. 62-122015, the contact portions come into contact with and separate from each other, resulting in fatigue damage of the contact portions, and the increase in durability is also restricted.

[0007]

As described above, in the conventional switch described in Japanese Patent Application Laid-Open No. 62-122015, the contact is brought into and out of contact by the sliding movement of the moving body, so that the durability is increased. It is difficult to move the moving body without damaging each part, and the versatility is limited. Further, in the conventional switch described in Japanese Utility Model Laid-Open Publication No. 59-187030, a plurality of coil springs having different urging forces are provided in order to prevent the switch portion from being damaged even if the moving body moves after the contacts are closed. In addition, the relationship between the moving distance of the moving body and the opening and closing of the switch may change due to the balance of the biasing force of the coil spring, and it is difficult to obtain highly accurate detection.

Therefore, a configuration is conceivable in which a reed switch is used instead of the contact switch, a magnet is provided on the moving body, and the reed switch is opened and closed by movement of the moving body.

However, for example, when the moving distance of the moving body is set large, the moving body is closed only when the magnet of the moving body is located near the reed switch, and this closed state may not be maintained. There is a problem that the open / closed state of the reed switch for movement cannot be variably set.

The present invention has been made in view of the above problems, and has as its object to provide a switch having high durability and high versatility.

[0011]

According to a first aspect of the present invention, there is provided a switch comprising: a substantially cylindrical main body having at least one open end; and a longitudinal reed switch having a longitudinal direction fixed along the axial direction of the main body. A moving body having a tip portion housed in the main body portion so as to be able to advance and retreat from an opening of the main body portion, and a moving body disposed in the main body portion for urging the moving body in a direction to advance from the opening of the main body portion. A biasing unit, a magnet unit provided in the main body unit for closing the reed switch, and a magnet unit provided in the mobile unit, when the moving body moves in the main body unit against the bias of the biasing unit. Magnetic force reducing means for opening the reed switch by reducing the magnetic force of the magnet unit with respect to the reed switch.

A magnet for closing the reed switch is provided on the main body, and the magnetic force of the magnet is reduced with respect to the reed switch by advancing and retreating to a movable body accommodated in the main body so as to be movable forward and backward. The moving distance of the moving body and the timing of opening and closing the reed switch can be easily set by setting the position where the magnetic force reducing means is provided on the moving body and the setting position of the non-contact reed switch and the magnet section. To improve durability and versatility.

According to a second aspect of the present invention, in the switch according to the first aspect, the magnetic force reducing means is a magnet or a magnetic material having a polarity opposite to that of the magnet portion.

Since the magnet or the magnetic material having the opposite polarity to the magnet portion is used as the magnetic force reducing means provided on the moving body, the magnet or the magnetic material having the opposite polarity substantially overlaps the magnet portion by the movement of the moving body. As a result, the magnet or the magnetic material constitutes a magnetic circuit with the magnet unit, and the magnetic effect of the magnet unit to be closed by the reed switch is reduced.
The variable setting of the moving distance of the moving body and the opening / closing timing of the reed switch can be easily obtained with a simple configuration.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of a switch according to an embodiment of the present invention will be described below with reference to the drawings.

1 to 4, reference numeral 1 denotes a switch body used for a brake system of a vehicle, for example.
The switch main body 1 has a substantially cylindrical main body 3 made of a metal such as aluminum or a synthetic resin and having openings 2a and 2b at both ends. The body portion 3 is substantially coaxially integrated with a substantially cylindrical body portion 4 having a flange-like holding portion 4a protruding inward at an opening edge on one end side and a holding portion 4a of the body portion 4. And a substantially cylindrical mounting portion 5 having an inner diameter smaller than the holding portion 4a of the body portion 4. Then, the end of the small-diameter mounting portion 5 on the side of the body portion 4 becomes a step-shaped retaining portion 6 protruding from the inner surface of the body portion 4, and the end surface of the retaining portion 6 facing the body portion 4 abuts. The outer end surface of the body portion 4 on the side of the mounting portion 5 becomes the reference surface 8. A male screw portion 9 is provided on the outer peripheral surface of the mounting portion 5, and the outer peripheral surface of the body portion 4 on the mounting portion 5 side is substantially engaged with a tool (not shown) for rotating the main body 3 around a central axis as a rotation axis. It is formed in the shape of a regular hexagon.

The body 3 has an inner diameter of the body 4.
A ring-shaped magnet portion 10 having substantially the same diameter as the inner diameter of the holding portion 4a is disposed in contact with the holding portion 4a. The magnet 10
Are magnetized such that the end face in the axial direction becomes the magnetic pole face.

A pedestal portion 11 is fitted and fixed in the main body portion 3 at a position opposite to the mounting portion 5 of the body portion 4 on the side of the large-diameter opening 2a at one end. This pedestal part 11,
It has a substantially cylindrical fitting portion 12 made of synthetic resin or the like and having an inner diameter substantially equal to the inner diameter of the holding portion 4a of the body portion 4. On the inner peripheral surface on one end side of the fitting portion 12, a flange portion 13 projecting inward in a wall shape is provided, a terminal chamber 14 is defined on one end side, and a switch chamber 15 is provided on the other end side. Are formed. A substantially cylindrical holding portion 16 is provided substantially coaxially toward the switch chamber 15 at the distal end of the flange portion 13. In the pedestal portion 11, the fitting portion 12 is inserted into the main body portion 3 from the switch chamber 15 side, and the distal end portion of the fitting portion 12 sandwiches and fixes the magnet portion 10 with the sandwiching portion 4a of the body portion 4. doing.

Further, a snap ring fitting 18 is fitted and fixed at an end of the pedestal portion 11 facing the opening 2a on one end side of the main body portion 3. The snap ring fitting 18 is a fitting portion of the base 11.
The pedestal portion 11 is prevented from coming off by abutting on the end of the pedestal portion 12.

A reed switch device 20 is attached to the pedestal portion 11. This reed switch device
Reference numeral 20 denotes a rod-shaped part 22 which is formed in a substantially elongated rod-like shape and has a longitudinal reed switch 21 for leading out lead contacts 21a, 21a at both ends in the longitudinal direction. It has a terminal portion 24 having a pair of terminals 23, 23 which are integrally provided and are electrically connected to a pair of reed contacts 21a, 21a of the reed switch 21, respectively. Then, in the reed switch device 20, the terminal portion 24 is inserted and accommodated in the terminal room 14 of the pedestal portion 11,
The rod-shaped part 22 is fitted and fixed to the holding part 16 of the pedestal part 11, the reed switch 21 is located in the switch chamber 15, and the rod-shaped part 22 is located substantially coaxially with the fitting part 12 of the pedestal part 11. Installed.

Further, terminals 23, 23
A connector 27 having contact terminals 26, 26 connected to the connector 3 is attached with its end extending from the main body 3.

At one end of the main body 3, a snap ring fitting is provided.
A filler 28, such as an epoxy resin, is provided to cover 18 and to lead out an end of the connector 27 and to integrally fix it to fill the gap.

On the other hand, reference numeral 29 denotes a coil spring as an urging means.
The reed switch 21 is mounted on the holding portion 16 of the main body 3 so as to include the reed switch 21 on the central axis.

A moving body 30 is provided in the main body 3. The movable body 30 is formed of a highly rigid synthetic resin into an elongated rod shape having an outer diameter substantially equal to the inner diameter of the mounting portion 5 of the main body 3. Further, the moving body 30 is formed in a substantially bottomed cylindrical shape having an accommodation concave portion 31 as an accommodation portion into which the rod-shaped portion 22 having the reed switch 21 attached to the central axis can be inserted is opened at one end side which is the base end side. I have.

Further, on the outer peripheral surface of the moving body 30, a housing recess is provided.
A flange is formed in the outer peripheral direction so that the outer diameter is substantially the same as the inner diameter of the holding portion 4a of the body portion 4 of the body portion 3 and the inner diameter of the fitting portion 12 of the pedestal portion 11 at the opening side of the body portion 3. A protruding restricting portion 32 is provided which comes into contact with the retaining portion 6 of the main body 3.

The axial dimension of the housing recess 31 of the moving body 30 is such that the leading end of the moving body 30 retreats almost completely into the main body 3 and the coil spring 29 interposed between the moving body 30 and the pedestal 11. Is set so that the tip of the rod-shaped portion 22 does not come into contact with the end surface of the housing recess 31 of the moving body 30 even when the moving body 30 moves to a state close to the completely collapsed state.

Further, on the outer peripheral surface of the end of the movable body 30 on the side where the housing concave portion 31 is opened, a magnetic force formed in a ring shape whose axial dimension is substantially the same as the axial dimension of the magnet portion 10 is formed. A magnet 35 as a reducing means is integrally attached to the end surface of the regulating portion 32 in contact with the end surface. The outer diameter of the magnet 35 is substantially the same as the outer diameter of the restricting portion 32, and when mounted, the outer peripheral surface is substantially flush with the distal end portion of the restricting portion 32. The other end of the coil spring 29 is substantially flush with the end surface of the moving body 30 with which the other end portion abuts. The magnet 35 is magnetized so that the end face in the axial direction becomes the magnetic pole surface similarly to the magnet part 10, and is attached so that the polarity is opposite to that of the magnet part 10.

Next, the assembling operation of the above embodiment will be described.

First, the reed switch 21 is always open, and the reed switch 21 is closed by the movement of the moving body 30, that is, a normally-open type switch body, that is, an off-on type switch body 1.
Will be described.

The magnet 35 is fitted and fixed on the outer peripheral surface of the end of the moving body 30 in advance. Further, the reed switch device 20 and the connector 27 are assembled on the pedestal portion 11. Further, the coil spring 29 is fitted from the reed switch 21 side and attached to the holding portion 16 of the pedestal portion 11 until one end side of the coil spring 29 contacts the end surface of the flange portion 13 of the pedestal portion 11.

Then, the main body 3 is attached to an assembling jig (not shown). The assembling jig has a female screw portion to which the male screw portion 9 of the mounting portion 5 of the main body portion 3 is screwed, and the male screw portion of the mounting portion 5 of the main body portion 3 until the reference surface 8 of the main body portion 3 abuts. The part 9 is screwed and attached. Then, the ring-shaped magnet portion 10 is inserted from the large-diameter opening 2a of the body portion 4 of the main body portion 3 until it comes into contact with the holding portion 4a of the body portion 4 so as to be dropped. Next, the main body 3 is inserted from the large-diameter opening 2a of the body portion 4 of the main body portion 3 from the distal end side of the movable body 30 provided with the magnet 35 until the regulating portion 32 contacts the retaining portion 6.

Next, the pedestal portion 11 to which the reed switch device 20 and the coil spring 29 are attached is inserted to some extent from the large-diameter opening 2a of the body portion 4 of the main body portion 3 on the reed switch 21 side. Then, in a temporarily fixed state where the pedestal portion 11 is inserted to the extent that the pedestal portion 11 does not come off from the main body portion 3, the reed switch 21 is
The connector 27 is connected to a detection device (not shown) so that the open / closed state of can be detected.

Thereafter, the snap ring 18 is inserted into the large-diameter opening 2a of the body 4 of the main body 3 by press-fitting and inserted together with the pedestal 11, and the pedestal 11 is positioned and fixed.

Then, remove from the jig for assembly,
In the large-diameter opening 2a of the body part 4 of the main body part 3, a snap ring fitting 18 is provided.
And a filler 28 such as an epoxy resin is filled around the connector 27 to assemble the switch body 1.

Next, the operation of the switch body 1 will be described.

For example, the male screw portion 9 of the mounting portion 5 of the switch body 1 is screwed into a female screw portion provided in a vehicle body component (not shown) until the reference surface 8 of the main body 3 comes into contact with the female screw portion. The moving body 30 is disposed such that the tip end of the moving body 30 faces a rod-shaped body that is an interlocking detection object.

In a state where the object to be detected does not move the moving body 30, that is, in a state where the magnet portion 10 and the magnet 35 shown in FIGS. 1 and 3 overlap on substantially the same plane, in this state, Since the magnet unit 10 and the magnet 35 have opposite polarities,
As shown in FIG. 3, a magnetic closed circuit is formed. For this reason,
The magnetic force of the magnet part 10 and the magnetic force of the magnet 35
The reed switch 21 is in an open state and is turned off because the magnetic force is reduced and the influence of the magnetism is reduced.

When the object to be detected moves, for example, when the brake device is actuated, the object to be detected comes into contact with the distal end of the moving body 30, and the object to be detected further moves, as shown in FIG. Moving body against the bias of coil spring 29
30 is moved back into the main body 3. And
When the moving body 30 moves a predetermined distance, as shown in FIG.
The magnet portion 10 and the magnet 35 arranged with the opposite polarities are in a state of being displaced. For this reason, the magnet unit 10 cannot form a magnetic closed circuit with the magnet 35, and the reed switch 21 is closed and turned on by the magnetic force of the magnet unit 10 under the influence of the magnetic force of the magnet unit 10,
It detects that the brake has been operated. Note that this on state is such that even if the moving body 30 moves further, the magnet 35 is
Since the distance from the magnet 10 increases, a magnetic circuit between the magnet 10 and the magnet 35 is not formed, so that the reed switch 21 is maintained in the ON state under the influence of the magnetism of the magnet 10.

On the other hand, the reed switch 21 is always closed, and the reed switch 21 is opened by the movement of the moving body 30, that is, the normally-closed type switch body 1.
In the case of, the reed switch 21 is located on the base end side of the rod-shaped portion 22, and the magnet portion 10 is also a large-diameter opening of the body portion 4.
It is arranged so as to be deflected to the side 2a and to face the reed switch 21.

Therefore, when the moving body 30 is not pushed by the detected object, the magnet 35 provided on the moving body 30 is
4, the reed switch 21 shown in FIG. 4 is affected by the magnetic force of the magnet unit 10 and is closed and turned on. When the moving body 30 is retreated by the detected body and moves a predetermined distance, the magnet section 10 and the magnet 35 are overlapped as shown in FIG. The reed switch 21 is opened and turned off by reducing the influence of the magnetic force on the reed switch 21.

The same applies when the magnet 35 and the reed switch 21 are arranged at the same position, and the magnet 35 is displaced toward the tip of the moving body 30.

Further, an on-off-on type switch configuration is provided by disposing the reed switch 21 at an intermediate portion of the bar-shaped portion 22 and disposing the magnet portion 10 so as to face the reed switch 21. Is also obtained.

As described above, the magnet section 10 for closing the reed switch 21 is provided on the main body section 3 and the main body section 3 is closed.
In order to provide a magnet 35 as magnetic force reducing means for opening the reed switch 21 by reducing the magnetic force of the magnet unit 10 with respect to the reed switch 21 by moving forward and backward on the moving body 30 accommodated in the movable body 30 which can be freely retracted, The moving distance of the moving body 30 and the opening / closing timing of the reed switch 21 can be variably set according to the position where the magnet 35 is disposed and the position where the reed switch 21 and the magnet unit 10 are disposed. Only needs to be changed, and the versatility can be improved.

Also, the reed switch is always operated by the magnet unit 10.
The state in which the magnet 21 is closed is reduced according to the moving state of the moving body 30 to which the magnet 35 is attached, so that the magnet 35 forms a magnetic closed path to reduce the influence of the magnetic force of the magnet unit 10 on the reed switch 21. A variable setting of the opening / closing timing of the reed switch 21 can be easily obtained by the configuration, the manufacturability can be improved, and the miniaturization can be easily achieved.

Furthermore, the end of the rod 22 does not come into contact with the housing recess 31 in which the rod 22 for disposing the reed switch 21 is relatively fitted in the movable body 30 even when the movable body 30 moves. After the reed switch 21 is opened and closed, the moving body 30 can be moved further without the rod-shaped portion 22 abutting. Although the moving portion cannot move and the moving range is limited, in the above-described embodiment, the moving body 30 has a simple configuration in which the housing concave portion 31 is formed in a substantially cylindrical shape, and does not cause damage due to contact. In addition, the moving range of the moving body 30 can be increased, and the open / closed state of the reed switch 21 can be easily variably set.

Further, since the non-contact type reed switch 21 is used, there is no fatigue damage of the contact portion due to repetition of contact contact / separation which occurs in the conventional contact type switch which is opened / closed by contact / separation of the contact, thereby improving durability. it can.

In the above embodiment, as the magnetic force reducing means for reducing the influence of the magnetic force of the magnet unit 10 on the reed switch 21, a description will be given by using the magnet 35 which forms a closed magnetic path by approaching and magnetically shields. However, a magnetic material such as ferrite or various magnetic metals may be used. This magnetic material also intervenes between the magnet unit 10 and the reed switch 21 to form a magnetic closed circuit, thereby reducing the influence of the magnetic force of the magnet unit 10 and opening the reed switch 21. In addition, any device that opens the reed switch 21 by interposing between the magnet unit 10 and the reed switch 21 to reduce the influence of the magnetic force of the magnet unit 10 can be used.

Further, a plurality of magnets 35 may be provided.
According to this configuration, the reed switch 21 is moved a plurality of times by the movement of the moving body 30, such as an off-on-off type or an on-off-on-off type when two are provided. It can be opened and closed, and for example, by detecting the opening and closing interval time of the reed switch 21,
It can also detect the detection status such as 30 moving speeds.

The positioning member for positioning the pedestal portion 11 is not limited to the retaining ring 18, but can be inserted into the main body 3 but positioned so as not to fall off by the urging of the coil spring 29 as urging means. Any one-way configuration, such as a configuration in which a plurality of claws or the like are provided on the inner peripheral surface of the main body 3 and which are inclined in the insertion direction side of the pedestal 11 such as a downer, etc. The unit 3 may be configured. According to this configuration, it is not necessary to use the snap ring fitting 18 as a separate member, the number of parts can be reduced, and the assembly manufacturability can be improved.

On the other hand, a plurality of reed switches 21
May be arranged so that the operating position is different in the axial direction of the main body 3. According to this configuration, a plurality of magnets
As in the case of providing 35, it is also possible to detect a detection situation such as the moving speed of the moving body 30.

Further, the reed switch 21 may be directly provided in the main body 3 without using the pedestal 11.

On the other hand, the main body 3 is connected to the body 4 having different diameters.
The mounting portion 5 is formed integrally on the same axis to form the retaining portion 6, and the restricting portion 32 is formed on the outer peripheral surface of the moving body 30 in a flange shape.
However, for example, the main body 3 is formed in a cylindrical shape in which the body portion 4 and the mounting portion 5 have substantially the same diameter, and the retaining portion 6 is formed inward on the inner peripheral surface in a flange shape. Alternatively, any configuration may be adopted in which the moving body 30 contacts the retaining portion 6 and regulates the moving body 30 in the protruding direction.

The urging means is not limited to the coil spring 29, but may be any means for urging the moving body 30 in the direction in which it protrudes from the main body 3.

Further, a housing which is open in the axial direction is provided at the other end of the movable body 30 which is the tip end side of the side where the housing recess 31 is not open, and a steel ball as a sphere is rotatable in this housing. May be held. By providing the steel balls, even if a force for urging and moving the moving body 30 is applied in a direction intersecting the moving direction of the moving body 30, the steel balls rotate to smoothly move the moving body 30. 30 can be moved.

[0055]

In the embodiment shown in FIGS. 1 to 4, the magnet part 10 is set to have an outer diameter of 24 mm, an inner diameter of 17 mm, a thickness of 4 mm, and a surface magnetic flux density of 840 × 10 ^-4 T, The magnet 35 is set to have an outer diameter of 14 mm, an inner diameter of 9 mm, a thickness of 3 mm, a surface magnetic flux density of 440 × 10 ^-4 T, and a measuring device for measuring the magnetic flux density is provided instead of the reed switch 21. The change in the magnetic flux density at the position where the reed switch 21 was disposed due to the movement of the moving body 30 was measured. The result is shown in FIG.

From the results shown in FIG. 5, in the state shown in FIGS. 1 and 3 where the moving body 30 is not moving, the magnetic flux density is almost zero, but as shown in FIG. 2, the moving body 30 retreats. It can be seen that the magnetic flux density increases as moving in the direction.

That is, even when the magnet 35 is closest to the reed switch 21 as shown in FIG.
The reed switch 21 does not close,
When the reed switch 21 is closed by the influence of the magnetic force of the magnet unit 10 as the magnet 35 moves away, for example, the magnetic flux density is affected by the magnetic force of 100 × 10 ⁻⁴ T, the moving body 30 becomes It can be seen that it closes when it moves about 1.5 mm. Therefore, it can be seen that the timing for opening and closing the reed switch 21 can be easily set by setting the sensitivity of the reed switch 21.

Next, a test for confirming the open / closed state of the reed switch 21 was conducted in the same manner by using, for example, a cold-rolled steel material (SPCC material) as a magnetic material instead of the magnet 35 of the above embodiment. In the embodiment shown in FIGS. 1 to 4,
As shown in FIG. 6 and FIG.
The magnetic material 40 formed in a substantially ring shape having an outer diameter of 8.2 mm and an inner diameter of 7.times.5 mm, an inner diameter of 12.5 mm, a thickness of 5 mm, and a surface magnetic flux density of 560.times.10.sup.- ⁴ T was set. 8 mm, thickness dimension is set to 5 mm, and a measuring device for measuring magnetic flux density is provided in place of the reed switch 21 to measure the change in magnetic flux density at the position of the reed switch 21 due to the movement of the moving body 30. did. FIG. 8 shows the result.

From the results shown in FIG. 8, in the state shown in FIG. 6 where the moving body 30 is not moving, the magnetic flux density is approximately 30 × 1.
Although it is about 0 ^-4 T, it can be seen that the magnetic flux density increases as the moving body 30 moves backward as shown in FIG.

That is, the magnetic material 40 is
In the state shown in FIG.
The reed switch 21 does not close without being affected by the magnetic force of the magnet portion 10 facing the magnetic member 10 and the magnetic force of the magnet portion 10 is influenced by the magnetic material 40 as the magnetic material 40 moves away.
When the reed switch 21 that closes under the influence of the magnetic force of 0 × 10 ⁻⁴ T is used, it can be seen that the moving body 30 closes when it moves about 2.5 mm. For this reason, it can be understood that the timing for opening and closing the reed switch 21 can be easily set by setting the sensitivity of the reed switch 21 even with a magnetic material that forms a magnetic closed circuit by substantially overlapping the magnet unit 10.

[0061]

According to the first aspect of the present invention, the main body is provided with a magnet for closing the reed switch, and the movable body accommodated in the main body is movable with respect to the reed switch. Since the magnetic force reducing means for opening the reed switch by reducing the magnetic force of the magnet part is provided, the moving distance of the moving body is determined by setting the position where the magnetic force reducing means is provided on the moving body and the setting position of the non-contact reed switch and the magnet part. And the timing of opening and closing the reed switch can be easily and variably set, thereby improving durability and versatility.

According to the switch of the second aspect, in addition to the effect of the switch of the first aspect, a magnet or a magnetic material having a polarity opposite to that of the magnet portion is used as the magnetic force reducing means provided on the moving body. Since a magnet or a magnetic material of the opposite polarity is substantially overlapped with the magnet by the movement of the moving body, a magnetic circuit is formed with the magnet and the influence of the magnetic force of the magnet to be closed by the reed switch is reduced. With a simple configuration, variable setting of the moving distance of the moving body and the timing of opening and closing the reed switch can be easily performed.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view showing an embodiment of a switch according to the present invention.

FIG. 2 is a partially cutaway side view showing a situation in which the mobile object has moved.

FIG. 3 is an explanatory diagram showing a relationship among a reed switch, a magnet unit, and a magnet in FIG. 1;

FIG. 4 is an explanatory diagram showing a relationship among a reed switch, a magnet unit, and a magnet in FIG. 2;

FIG. 5 is a graph showing a change in magnetic flux density at a position of a reed switch due to movement of the moving body.

FIG. 6 is an explanatory view showing a relation among a reed switch, a magnet unit, and a magnetic material at all times in another embodiment of the switch of the present invention.

FIG. 7 is an explanatory diagram showing a relationship between a reed switch, a magnet unit, and a magnetic material when the moving body is moved.

FIG. 8 is a graph showing a change in magnetic flux density at a position of a reed switch due to the movement of the moving object.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Switch body 2a, 2b opening 3 Body part 10 Magnet part 21 Reed switch 29 Coil spring as urging means 30 Moving body 35 Magnet as magnetic force reducing means 40 Magnetic material

Claims (2)

[Claims] 1. A substantially cylindrical main body having at least one open end, a longitudinal reed switch having a longitudinal direction fixed along an axial direction of the main body, and a tip inside the main body. A moving body accommodated so as to be able to advance and retreat from the opening of the main body; an urging means disposed in the main body for urging the moving body in a direction to advance from the opening of the main body; and the lead provided in the main body. A magnet unit for closing a switch; and a magnetic force of the magnet unit with respect to the reed switch when the moving body moves in the main body against the bias of the biasing means provided on the moving body. A magnetic force reducing means for reducing the opening of the reed switch. 2. The switch according to claim 1, wherein the magnetic force reducing means is a magnet or a magnetic material having a polarity opposite to that of the magnet portion.