JPH09106744A - Overturn switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a contact from closing even if a floor face detection piece is pushed in when an electric apparatus is overturned. SOLUTION: An overturn switch is provided with a floor face detection piece 26 which moves up and down against a main body 22, a switch push bar 29 which moves up and down together with the detection piece 26 so as to operate a moving contact piece 24, and a coil spring (an energizing means) 28, 29 which energizes the detection piece 26 at the detection time of a floor face by the detection piece 26, and also pushes up the pushing bar 26. An approximately reverse truncated cone-like recessed portion 36 whose top face opening is covered by a lid 23 having a through hole 38 in the central portion is provided in the main body 22, and a through hole 40 is provided in the bottom wall of the recessed portion 36. A pushing bar control weight 30 having a center hole 47, through which a push bar 26 can be interposed, in the central portion, is contained in the recessed portion 36 by its self-weight so as to be free in moving. In the weight 30, the peripheral stopper portion 48 of the center hole 47 is arranged to face both through holes 38, 40 by free movement at an overturning time, and also the center hole 47 is arranged to face both through holes 38 40 in a non-overturning state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable electric heater such as a portable electric heater, an electric kitchen product, an electric pot, a table lamp, etc., which is appropriately carried and installed on an arbitrary place on a floor surface (a mounting surface). The present invention relates to a fall switch which is provided in a device as a safety device when the device falls, and which cuts off the power supply circuit of the device when the electric device body falls.

[0002]

2. Description of the Related Art As shown in the cross-sectional view of FIG. 14, a conventional tipping switch has a cylindrical guide 1 protruding downward.
A fixed switch contact piece 3 having a fixed contact 3a and a movable contact 4 made of a leaf spring having a movable contact 4a connected to and separated from the fixed contact 3a are attached to the upper portion of the main body 2 having There is. A floor detector 5 having a stepped cylindrical shape is attached to the guide 1 such that the lower end of the detector 5 is protruded from a bottom opening of the guide 1 and is vertically movable. A switch push rod 6 is vertically moved above the detector 5. It is fitted freely. A coil spring 7 for pushing up the switch push rod 6 is housed in the floor detector 5.

The fall switch having the above construction is attached to the bottom surface of an electric device such as an electric stove, and is used by being inserted in series into a power supply circuit of the electric device. In this use, as the floor surface detector 5 in contact with the floor surface relatively rises by the predetermined stroke S, the coil spring 7 is compressed and the switch push rod 6 is raised to push up the movable contact piece 4. The movable contact 4a is brought into contact with the fixed contact 3a. As a result, this tipping switch is held in the closed state to enable operation of the electric device.

Further, when the electric equipment falls and the floor surface detector 5 separates from the floor surface, the spring force of the coil spring 7 causes the floor surface detector 5 to further project and the switch push rod 6
The pushing force of is lost. As a result, the movable contact piece 4 is returned by the elastic force so as to be separated from the fixed contact piece 3 and the two contacts 3a and 4a are separated from each other, so that the power switch circuit can be turned off by this tipping switch.

[0005]

Such an operation is performed even when the electric device falls over in the event of an earthquake. But,
In the event of an earthquake to the extent that the electric equipment falls, various articles in the room also fall or fall at the same time, and it is conceivable that the floor detector 5 of the fall switch may be pushed by such articles.

By the way, in the case of such an emergency, the conventional fall switch does not take any measures,
When the electric device falls, the contact points 3a and 4a may come into contact with each other due to the pushing force applied to the floor detector 5, and the fall switch may be turned on again.

Therefore, the problem to be solved by the present invention is to provide a tipping switch which can surely prevent the contacts from closing even when the floor detector is pushed in the tipping state of the electric device.

[0008]

In order to solve the above-mentioned problems, the invention of claim 1 has a substantially inverted frustoconical or hemispherical concave portion having an upper surface opened, and the central portion of the bottom wall of this concave portion. And a main body having a guide projecting downward from the recess, and a through hole provided at the center of the recess. A lid, a first switch contact located above the recess and attached to the body, and having a fixed contact;
It has a movable contact located between the switch contact piece and the recess and attached to the main body, and is brought into contact with and separated from the fixed contact, and is elastically deformable, and the movable contact is fixed by the elasticity. A second switch contact piece that is held at a position away from the floor, a floor surface detector that is vertically movable along the guide, the both through holes and the recess that are vertically movable together with the detector. A switch push rod that passes through the center of the second switch contact piece and is separated from the lower side of the second switch contact piece; and when the floor surface detector detects the floor surface, the floor surface detector is biased downward and the switch It has a biasing means for pushing up the push rod and a central hole through which the switch push rod can be inserted, and is formed in a similar shape to the concave portion and smaller than the concave portion. It is housed movably and is arranged so that the peripheral stopper portion of the center hole faces both the through holes by free movement when falling, and the center hole faces the both holes in the non-falling state. The push rod control weight is provided.

In the fall switch according to the present invention, when the electric device to which the switch is attached is normally installed on the floor surface, the main body of the switch is held in a vertical posture and the inside of the recess is The push rod control weight is arranged at the bottom of the recess while keeping the most stable posture by its own weight, the lower end of the center hole of the weight communicates with the through hole of the main body, and the upper end faces directly below the through hole of the lid. . In this case, since the floor surface detector has its lower end in contact with the floor surface and is pushed upward along the guide, the switch pushing rod is pushed up by the urging force of the urging means, and the upper portion of this rod has the above-mentioned two passages. The second switch contact piece is pushed up against its elastic force through the hole and the central hole of the push rod control weight. As a result, the contacts of both contact pieces are held in the connected state, and the fall switch is held in the state in which the power supply circuit of the electric device is closed. Moreover, in this case, the urging means urges the floor surface detector downward, in other words, in a direction projecting from the bottom surface of the electric device.

When the electric device falls down in such a use state, the floor surface detector separates from the floor surface, so that the switch push rod is recessed as the biasing means causes the floor surface detector to project more greatly from the bottom surface of the electric device. Moved outside. As a result, the switch push rod separates from the second switch contact piece, and the contact piece separates from the first switch contact piece due to its elastic force and both contacts are opened. Holds open.

In this overturned state, the switch push rod is moved to the outside of the recess as described above, so that the restraint of the push rod control weight by the push rod is released. Therefore, the push rod control weight freely moves in the recess due to its own weight and is arranged at the lowest position in the posture of the recess at that time. Due to the movement of the push rod control weight, the center hole is located off the axial long line of the switch push rod, and the peripheral stopper portion around the center hole is formed in the through hole of the main body and the through hole of the lid. Placed opposite to these between
In other words, it is located on the axis extension of the switch push rod. The peripheral stopper portion thus arranged is used as a stopper which prevents the switch push rod from moving toward the through hole of the lid through the through hole of the main body.

Therefore, when the floor surface detector receives a pushing force in the overturned state, the switch pushing rod penetrates the pushing rod control weight and is pushed in the direction of the second switch contact piece. It can be stopped by the stopper action.

Similarly, in order to solve the above problems,
The invention of claim 2 has a recess having an open upper surface, a through hole is provided in the center of the bottom wall of the recess, and a guide is provided so as to project downward in a continuous manner below the recess. A main body, a first switch contact located above the recess and attached to the main body and having a fixed contact, and a first switch contact located between the first switch contact and the recess and attached to the main body; And a second switch contact piece that has a movable contact that is brought into contact with and separated from the fixed contact and that is elastically deformable and that holds the movable contact at a position separated from the fixed contact by the elasticity, and along the guide. A floor switch which is vertically movable, a first switch push rod which has a head at its upper end and is vertically movable by passing the head through the through hole, and the floor sensor The floor surface provided to move up and down Energizing means for urging the floor surface detector downward and pushing up the first switch push rod when the spawn detects the floor surface, the second switch contact piece and the through hole across the recess. A support shaft that is attached between the support shaft and the through hole and that is bent so that the intermediate portion facing the through hole is the lowest, and has a substantially V-shaped support shaft; Along with this, there is an elongated hole extending in the longitudinal direction. The elongated hole is fitted to the support shaft and is rotatable by its own weight in the axial direction of the shaft within the length range of the elongated hole. It is mounted so as to be movable in the longitudinal direction, and is arranged so as to deviate from the extension of the axis line of the first switch push rod by free movement during a fall, and is placed just above the first switch push rod in the non-falling state. And the first switch push rod is raised. Create at those and a second switch pushrod relayed to the second switch contact piece.

In the fall switch according to the present invention, when the electric device to which the switch is attached is normally installed on the floor surface, the main body of the switch is held in a vertical posture and the inside of the recess is The second switch push rod is arranged in a vertical state while maintaining the most stable posture due to its own weight. In this case, since the floor surface detector has its lower end in contact with the floor surface and is pushed upward along the guide, the first switch push rod is pushed up by the urging force of the urging means, and the head of this rod is It engages with the head engaging portion of the second switch push rod which is vertically positioned right above it, and pushes up this second switch push rod. This pushing up is allowed by the long hole fitted in the support shaft.

Since the second switch push rod pushed up in this way pushes up the second switch contact piece against its elastic force, each contact point of both contact pieces is held in the connected state, and the tipping switch of the electric device is held. The power circuit is kept closed. Moreover, in this case, the urging means urges the floor surface detector downward, in other words, in a direction projecting from the bottom surface of the electric device.

When the electric device falls down in such a state of use, the floor surface detector separates from the floor surface, so that as the biasing means projects the floor surface detector to a larger extent from the bottom surface of the electric device, the first switch push rod. Is also moved in the same direction, and the restraint of the second switch push rod by this push rod is released. Therefore, the second switch push rod is moved by its own weight to the lowest position of the support shaft in the posture of the concave portion at that time, or is rotated around the axis of the support shaft.
Alternatively, these operations are performed at the same time, and the first switch push rod is disengaged from the extension line of the axis line.

As a result, the pressing of the second switch push rod against the second switch contact piece disappears, so that this contact piece is separated from the first switch contact piece by its elastic force and both contacts are opened. Therefore, this fall switch keeps the power circuit of the electric device open.

In this fall state, the second switch push rod is removed from the extension line of the axis of the first switch push rod as described above. Therefore, when the floor surface detector receives a pushing force in the fall state, The first switch push rod is second
The switch push rod is not pushed, and therefore the second switch contact piece is not pushed via this second switch push rod.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a perspective view showing a configuration of an electric heater which is an example of a portable electric device. A front and rear cases 12 and 13 of the heater 11 and an operation panel 14 are combined in a main body case 15. Includes a blower composed of a motor and a fan (not shown), and a ceramic heater 16 that can ventilate the lower part of the blower
(See FIG. 2). A blowing louver 17 facing the ceramic heater 16 is provided at the bottom of the front case 12.
The rear case 13 is provided with an intake port (not shown).

The operation of the blower is set by an operating time setting timer switch 18, and the heat generation amount of the heater 16 is set by a wattage changeover switch 19. Therefore, when the electric heater 11 is operated, the air sucked from the rear surface of the main body case 15 by the blower is
Since it is supplied to the heater 16 which is generating heat so as to pass through from the rear side to the front side, the blowing louver 1
Warm air is blown to the front side of the main body case 15 through 7, so that heating can be performed.

In the electric heater 11 which is appropriately carried to any place and used, the electric heater 11 is inserted in series in its power circuit,
A fall switch 21 is attached to stop the operation of the heater 11 if it falls. As shown in FIG. 2, the switch 21 is provided so as to penetrate the bottom wall 15a of the main body case 15 and is pushed by the floor surface (mounting surface) A on which the electric heater 11 is placed. It is turned on and turned off when it is away from the floor surface A.

As shown in FIGS. 3 to 6, the overturn switch 21 includes a main body 22, a lid 23, and a first switch contact piece 24.
, The second switch contact piece 25, the floor surface detector 26, the first
The coil spring 27, the second coil spring 28, the switch push rod 29, and the push rod control weight 30 are provided.

The main body 22 made of a synthetic resin such as polycarbonate is provided with a threaded portion 31 at one end of the main body 22a having a rectangular shape in plan view, and a threaded portion 32 at the other end. A support tube portion 33 in the shape of a rectangular tube is provided surrounding the upper portion of the portion 32. The main body 22a is
Both screw thread portions 3 are inserted into the first and second bosses (only the first boss is shown by reference numeral 15b in FIG. 2) provided on the bottom wall 15a.
Screws 3 that are individually fitted and positioned at the bottoms of the first and the second parts 32, and are screwed into the first boss 15b through the screw threaded part 31.
It is fixed to the bottom wall 15 by means of 4 (see FIG. 2).

On the upper surface of the central portion in the longitudinal direction of the main body portion 22a, there is provided a substantially inverted truncated cone-shaped recess 36 having an open upper surface. The recess 36 may have a hemispherical shape with an open upper surface. A horizontal screwing tongue piece 36a is provided on the opening edge of the recess 36.
(See FIG. 3) is integrally projected, and a hole 36b (see FIG. 4) is provided at a position corresponding to this in the radial direction. A through hole 38 is provided in the center of the bottom wall of the recess 36. The through hole 38 is formed by an inner space of a downwardly facing short cylindrical portion 38a. In other words, the main body 22
An upper end opening of a cylindrical portion 38a protruding from the lower surface of the central portion in the longitudinal direction of a is opened in the central portion of the bottom wall of the recess 36.

On the lower surface of the central portion of the main body portion 22a in the longitudinal direction, a guide 39 is provided so as to extend below the recess 36.
The guide 39 has a larger diameter than the cylindrical portion 38a, covers the cylindrical portion 38a, and is formed as a cylinder longer than the cylindrical portion 38a. The lower end of the guide 39 is open. The guide 39 is provided with a pair of elongated holes (only one is shown in FIG. 3) 39a extending in the longitudinal direction and facing each other in the radial direction. The guide 39 vertically penetrates the bottom wall 15 a, and the lower portion thereof projects outside the main body case 15.

The lid 23 is made of a thin metal plate and has a circular through hole 40 in the center thereof. As shown in FIG. 3 and FIG. 4, the lid 23 has a tongue edge 23a projecting from the periphery thereof inserted into the hole 37b, and is fixed to the threaded tongue piece 36a with a screw 41 so that the concave portion 36 It is attached to cover the top opening. The through hole 40 of the lid 23 thus attached faces directly above the through hole 38.

The base end portion of the first switch contact piece 24 and the base end portion of the second switch contact piece 25 are made of a synthetic resin spacer 42 fitted to the upper end portion of the support tube portion 33, and pass through the spacer 42. And a screw 43 that is screwed into the threaded portion 32. The base end portion of the second switch contact piece 25 is the support tubular portion 3
3 and the spacer 4 fitted so as to cover it
The first switch contact piece 24 is sandwiched between the upper end of the spacer 42 and the head of the screw 43.

First switch contact piece 24 as a fixed contact plate
Is formed by bending a copper plate, and its tip is arranged above the recess 36, and the fixed contact 24a is caulked to this portion. The second switch contact piece 25 as a movable contact plate is a flat plate of an elastically deformable phosphor bronze plate, and its tip is disposed between the recess 36 and the tip of the first switch contact piece 24. In this portion, the movable contact 2 which comes in contact with and separates from the fixed contact 24a from below.
4a is caulked. The tip portion of the second switch contact piece 24 faces directly above the through hole 40.

The floor surface detector 26 made of a synthetic resin such as polycarbonate has a cylindrical inner cylinder portion 45 provided inside a cylindrical outer cylinder portion 44 having a bottom. The outer cylinder portion 44 has a pair of locking portions 46 (only one is shown in FIG. 3) sandwiched between a pair of notches 46a cut from the upper end thereof.
Claws 46b are formed on the outer surfaces of the locking portions 46. The floor detector 26 is fitted in a guide 39 through its lower end opening so as to be vertically movable. Upon this fitting, the claw 46b can pass through the lower end of the floor surface detector 26 with the bending of the locking portion 46, and after this passing, the locking portion 46 returns to its original state, so that the claw 46b has a long hole. It is fitted in 39a. As a result, the floor surface detector 26, which is restricted by the long hole 39a and is movable in the vertical direction, is prevented from falling off the guide 39.

The stainless steel first coil spring 27 and the second coil spring 28 form a biasing means for the floor surface detector 26 and the switch push rod 29. Specifically, the lower part of the first coil spring 27 has an outer cylindrical portion 44 and an inner cylindrical portion 4
5 and the upper end of the cylindrical portion 3
It is loosely fitted around 8a, and when the floor surface detector 26 detects the floor surface A, the detector 26 is urged downward.
The second coil spring 28 has a smaller spring force and is thinner than the first coil spring 27, and is housed in the inner tubular portion 45. This coil spring 28 is the floor detector 26.
Detects the floor surface A, pushes up the switch push rod 29 and urges the floor surface detector 26 downward.

The switch push rod 29, which is formed of a synthetic resin such as polycarbonate in the shape of an elongated cylinder, has its lower end fitted to the upper end of the second coil spring 28 and is vertically supported. The push rod 29 is fitted and supported in the through hole 38 at the upper portion thereof, and is projected through the central portion of the recess 36 and the through hole 40 of the lid 23 when pushed up. .

The push rod control weight 30 made of steel wire rod (SWRH) has a central hole 47 into which the switch push rod 29 can be inserted, has a similar shape to the recess 36, and is smaller than the recess 36. Has been formed. The weight 30 is housed in the recess 36 and is movable along the inner surface of the recess 36 by its own weight. The push rod control weight 30 is arranged at a position where a peripheral stopper portion 48, which is a peripheral portion of a central hole 47 thereof, faces both the through holes 38 and 40 by free movement of the electric heater 11 when the electric heater 11 falls. At the same time, when the electric heater 11 is in the non-falling state, the central hole 47 is arranged at a position facing both the through holes 38 and 40.

The fall switch 21 having the above-mentioned structure screwed to the main body case 15 of the electric heater 11 has the main body case 1
5 is lifted while maintaining a normal posture,
It is in the free state shown in (A).

In this state, the floor surface detector 26 is separated from the floor surface and does not detect the floor surface A, so that it is maximally projected downward from the guide 39 by the urging force of the first coil spring 27. The claw 46b is hooked on the lower end of the long hole 39a. As a result, the switch push rod 29, which is lowered together with the floor surface detector 26, is lowered most, and the upper end portion of the switch push rod 29 is recessed and supported in the through hole 38 without protruding into the recess 36. Therefore, both switch contacts 24,
The contacts 24a, 25a of 25 are separated, and the overturn switch 21 is opened.

Moreover, in this state, the push rod control weight 3
Due to its own weight of 0, this weight 30 is
Holding the most stable posture in contact with the bottom wall of the recess 3
The central hole 47 is located at the bottom of the No. 6 and has both through holes 38, 4
It is located between 0 and exactly opposite to these.

FIG. 5B shows a state in which the electric heater 11 is placed on the floor surface A in the correct use posture. In this state, since the floor surface detector 26 is pushed up by the floor surface A, the upper portion of the switch push rod 29, which is lifted together with the floor surface A, passes through the center hole 47 and the through hole 40 of the lid 23, and the second switch connection The piece 25 is elastically deformed and pushed up and held. As a result, the movable contact 25a of the contact piece 25
Is pressed and held by the fixed contact 24a of the first switch contact piece 24. That is, the overturn switch 21 is held in a closed (turned on) state, thereby enabling the electric heater 11 to be used.

At this time, the first and second coil springs 27, 2
8 is compressed (note that only the first coil spring 27 is compressed at first, and the second switch contact piece 25 is pushed up via the switch push rod 29 from the middle of the compression of the coil 27. 27 and 28 are both compressed.) However, the contact pressure of the contacts 24a and 25a depends exclusively on the spring force of the second coil spring 28, and the spring force of the first coil spring 27 directly affects the second switch contact piece 25. Never join.

Therefore, as in the case where the floor surface A is rugged, it fluctuates according to the length of the fluff of the carpet.
As much as the spring force of the coil spring 28, the contact pressure does not fluctuate, the fluctuation of the contact pressure due to the state of the floor surface A can be reduced, and an excessive pushing force is applied to the second switch contact piece 25. It can be prevented. Moreover, for this reason, a large stroke of the floor surface detector 26 can be secured, and the protruding length from the guide 39 can be reduced as shown in FIG. 5B.

When the electric heater 11 falls down due to an earthquake or the like during use,
Moreover, the state of the tipping switch 21 when the floor detector 26 of the tipping switch 21 receives the pushing force F is shown in FIG.
Is shown in

First, since the floor surface detector 26 no longer detects the floor surface A as the electric heater 11 falls down, at the same time, the detector surface 26 is mainly caused by the urging force of the first coil spring 27 to cause the tip of the guide 39 to move. The switch push rod 29, which is projected to the maximum from the above and is moved together with it, is retracted into the through hole 38 without projecting into the recess 36. As a result, the pressing force on the second switch contact piece 25 disappears, so that the contact piece 25 elastically recovers and separates from the first switch contact piece 24. Therefore, these two contacts 24
When a and 25a are separated, the overturn switch 21 is opened to turn off the power supply circuit of the electric heater 11. The state immediately after such a fall is the same as the state in which FIG.

Then, the switch push rod 29 is disengaged from the center hole 47 of the push rod control weight 30, and the weight 30 is no longer restrained. Therefore, the push rod control weight 30 is depressed by its own weight depending on the fall posture. Slide down to the lowest position. At this time, the lid 23 prevents the push rod control weight 30 from falling out of the recess 36.

As a result, as shown in FIG. 6, the center hole 47 of the push rod control weight 30 is positioned off the axial long line of the switch push rod 29, and the center hole 47 is located.
A peripheral stopper portion 48 of the main body 22 is provided with a through hole 38 and a lid 23.
Between the through holes 40 and the through holes 40. In other words, the peripheral stopper portion 48 is located on the extension line of the switch push rod 29.

The peripheral stopper portion 48 thus arranged
Is the floor surface detector 26 by the external force F in the fall state.
As the switch is pushed in, the switch push rod 29 becomes
Inside, the movement toward the central hole 47 toward the lid 23 is hindered.

That is, such a push rod control weight 30
After the switch push rod 29 hits the outer peripheral stopper portion 48 by the stopper action by, it is possible to prevent the switch push rod 29 from being pushed in the direction of the second switch contact piece 25 any more. According to this, even if the floor surface detector 26 is inadvertently pushed in the overturned state, it is possible to reliably prevent the contacts 24a and 25a from closing. In addition, thereby, it is possible to prevent the electric heater 11 including the tipping switch 21 from being turned on again when the electric heater 11 falls, and it is possible to further enhance safety.

7A and 7B show a second embodiment of the present invention. The overturn switch 21 according to the second embodiment is different from the first embodiment only in the inner surface structure of the concave portion 36, and the rest of the configuration is shown in FIG.
The configuration is the same as or similar to that of the overturn switch 21 of the first embodiment shown in FIGS. 1 to 6 including a portion not shown in FIG. Therefore, for configurations not shown, FIGS. 1 to 6 will be substituted, and the same or similar components shown in the drawings will be assigned the same reference numerals as those in the first embodiment to explain the configurations and Although the description of the action and effect based thereon is omitted, these same or similar components also form a part of the configuration of the overturn switch 21 according to the second embodiment.

In the second embodiment, the main body 22
A large number of contact protrusions 36c are provided on the inner surface of the recess 36. These convex portions 36c are formed by, for example, linear ribs extending from the bottom surface of the concave portion 36 to the open end of the upper surface.
Instead of this, a large number of protrusions whose tip has a spherical surface or the like may be provided. The configuration other than this point is the same as that of the first embodiment including the configuration of the portable electric device.

According to the overturn switch 21 according to the second embodiment, when the switch push rod 29 receives the pushing force in the overturned state of the electric heater including the switch 21, the switch push rod 29 moves to the first position. 2 switch contact 2
Pushing in five directions can be mechanically prevented by the push rod control weight 30 as in the fall switch according to the first embodiment. Thereby, the problem to be solved by the present invention can be solved. That is, even if the floor detector 26 is pushed down in the overturned state, the contacts 24a, 25a are closed, and it is possible to reliably prevent accidental reclosing of the overturn switch 21.

Moreover, by providing a large number of contact protrusions 36c on the inner surface of the recess 36, the contact area between the inner surface of the recess 36 and the push rod control weight 30 can be reduced. Thereby, when the electric heater is placed in the correct posture, the push rod control weight 30 is prevented from being in surface contact with the inner surface of the recess 36 made of synthetic resin and sticking to the push rod control weight 30 at the time of falling. It is possible to smoothly and surely move the inside of the concave portion 36 downward due to its own weight. Therefore, the operational reliability of the overturn switch 21 can be further improved.

8A and 8B show a third embodiment of the present invention. The tipping switch 21 according to the third embodiment differs from that of the first embodiment only in the peripheral structure of the push rod control weight 30, and the rest of the configuration is as shown in FIG.
The configuration is the same as or similar to that of the overturn switch 21 of the first embodiment shown in FIGS. 1 to 6 including parts not shown in (A) and (B). Therefore, for the configuration not shown, substitute FIGS. 1 to 6 and
The same or similar components shown in the drawings are denoted by the same reference numerals as in the first embodiment, and the description of those components and the description of the operation and effect based thereon will be omitted.
These same or similar components also form part of the configuration of the overturn switch 21 according to the third embodiment.

In the third embodiment, a large number of contact protrusions 48a are provided on the conical (or hemispherical) peripheral surface of the push rod control weight 30. Although these convex portions 48a are formed by, for example, linear ribs extending over the upper and lower ends of the weight 30, they may be formed by a large number of protrusions having a spherical surface or the like instead of this. The configuration other than this point is the same as that of the first embodiment including the configuration of the portable electric device.

According to the overturn switch 21 according to the third embodiment, when the switch push rod 29 receives the pushing force in the overturned state of the electric heater including the switch 21, the switch push rod 29 moves to the first position. 2 switch contact 2
Pushing in five directions can be mechanically prevented by the push rod control weight 30 as in the fall switch according to the first embodiment. Thereby, the problem to be solved by the present invention can be solved. That is, even if the floor detector 26 is pushed down in the overturned state, the contacts 24a, 25a are closed, and it is possible to reliably prevent accidental reclosing of the overturn switch 21.

Moreover, by providing a large number of contact protrusions 48a on the peripheral surface of the push rod control weight 30, the contact area between the inner surface of the recess 36 and the push rod control weight 30 can be reduced. Thereby, when the electric heater is placed in the correct posture, the push rod control weight 30 is prevented from being in surface contact with the inner surface of the recess 36 made of synthetic resin and sticking to the push rod control weight 30 at the time of falling. It is possible to smoothly and surely move the inside of the concave portion 36 downward due to its own weight. Therefore, the operational reliability of the overturn switch 21 can be further improved.

Next, a fourth embodiment of the present invention will be described with reference to FIGS. An electric heater (not shown, but this is the same as the one shown in FIGS. 1 and 2) that is appropriately carried to any place is inserted into the power supply circuit in series, A fall switch 121 is attached to stop the operation of the heater when it falls. The switch 121 is turned on when being pushed by the floor surface A on which the electric heater is placed, and is turned off when being away from the floor surface A.

As shown in FIGS. 9 to 13, the overturn switch 121 includes a main body 122 and a first switch contact piece 124.
A second switch contact piece 125, a floor detector 126,
It is provided with a first coil spring 127, a second coil spring 128, a support shaft 123, a first switch push rod 129, and a second stopper shaft 130.

The main body 122 made of a synthetic resin molded product such as polycarbonate is a strip-shaped main body main portion 122a in plan view.
A guide 139, which will be described later, is screwed to the lower side. A threaded portion 131 is provided at one end of the main body 122a, and a threaded portion 132 is provided at the other end.
And a support tube portion 133 having a rectangular tube shape surrounding the upper part of the. The main body main part 122a has both screw threaded parts 131 and 132 in first and second bosses provided on the bottom wall of the electric heater.
The lower parts of the screws are individually fitted and positioned, and the screw threaded portion 13
It is adapted to be fixed to the bottom wall by a screw (not shown) which is screwed into the first boss through 1.

A cylindrical recess 135 having an open upper surface is provided on the upper surface of the central portion of the main body 122a in the longitudinal direction. On the outer surface of the recess 135, a pair of horizontal connecting pieces 136 protruding in a direction orthogonal to the longitudinal direction of the main body 122a.
Are integrally projecting, and these connecting pieces 136 have a cylindrical screw receiving portion 13 extending vertically through the connecting pieces 136.
7 are integrally protruded.

A through hole 138 is provided in the center of the bottom wall of the recess 136. The through hole 138 is formed in the inner space of the downwardly facing stepped cylindrical portion 138a. In other words,
The upper end opening of the large-diameter cylindrical portion of the stepped cylindrical portion 138a provided on the lower surface of the central portion of the main body 122a in the longitudinal direction has a recess 136.
Is opened in the center of the bottom wall. In addition, 138a1 has shown the step part of the stepped cylindrical part 138a.

The guide 139 is also made of a molded product of synthetic resin such as polycarbonate, which is provided with a pair of connecting pieces 139b horizontally extending outward at the upper opening edge of a cylindrical guide portion 139a whose upper and lower ends are open. Then, the guide 139 is connected to the lower side of the main body main portion 122a via a screw 151 which is passed through the connecting piece 139b and screwed into the screw receiving portion 137 from below. As a result, the guide 139 is provided on the lower surface of the central portion in the longitudinal direction of the main body portion 122a so as to be continuous with the lower side of the recess 135 and project downward.

The cylindrical portion 139a of the guide 139 thus provided has a larger diameter and longer than the stepped cylindrical portion 138a and covers the cylindrical portion 138a, and a step portion 140 is formed on the inner peripheral surface of the lower end portion thereof. ing. The guide 139 vertically penetrates the bottom wall of the electric heater, and the lower portion thereof is projected to the outside of the electric heater.

The base end portion of the first switch contact piece 124 and the base end portion of the second switch contact piece 125 are made of a synthetic resin spacer 142 fitted to the upper end portion of the support cylinder portion 133, and pass through the spacer 142. And a screw 143 screwed into the threaded portion 132. The base end portion of the second switch contact piece 125 is sandwiched between the upper end surface of the support cylindrical portion 133 and the step portion of the spacer 142 fitted over the support cylinder portion 133, and the base end portion of the first switch contact piece 125. Is the upper surface of the spacer 142 and the screw 1
It is sandwiched between the head of 43.

First switch contact piece 12 as a fixed contact plate
4 is formed by bending a copper plate, and its tip is arranged above the recess 135, and a fixed contact 124a is caulked to this portion.
The second switch contact piece 125 as the movable contact plate is a flat plate of an elastically deformable phosphor bronze plate, the tip of which is the recess 1.
It is placed between the recess 135 and the tip of the first switch contact piece 124 so as to be in contact with and supported by the upper surface opening of 35 and close this opening. Fixed contact 124a is provided in this portion.
The movable contact 125a that comes into contact with and separates from the lower side is caulked. The tip of the second switch contact piece 124 has the through hole 1
Directly above 38.

Support shaft 123 made of a round bar of stainless steel or the like
Has a flattened connecting end 123a at both ends, and these parts are connected to the main body 122a via a screw 152 screwed into the screw receiving portion 137 from above. As a result, the support shaft 123 is fixed across the recess 135 in the direction orthogonal to the longitudinal direction of the main body 122a, and is disposed between the through hole 138 and the second switch contact piece 125. Then, the recess 135 of the support rod 123
As shown in FIG. 12 and the like, the portion positioned inside is bent in a substantially V shape so that the intermediate portion facing the through hole 138 is the lowest.

The second switch push rod 130 housed in the recess 135 is, for example, a weight made of steel wire rod (SWRH), has a head engaging portion 130a at its lower end, and has a longitudinal direction on the upper side thereof. Along the support shaft 123
Has a long hole 130b extending longer than the diameter of the. The head engaging portion 130 a is formed of a tapered hole, for example, a truncated cone-shaped recess, and is open to the lower end surface of the second switch push rod 130.

The second switch push rod 130 has a long hole 1
The support shaft 123 is fitted to the support shaft 123 and is movable along the support shaft 123 in the axial direction.
It is supported rotatably in the direction around the axis. The second switch push rod 130 is movable in the vertical direction within the length range of the elongated hole 130b, and the upper end thereof is positioned below the second switch contact piece 125 in a free state. It is like this.

The floor detector 126 made of a synthetic resin such as polycarbonate has a bottomed cylindrical shape with an open upper surface, and an annular locking collar 126 protruding outward at the opening edge of the upper surface.
a. The floor surface detector 126 is fitted in the cylindrical guide portion 139a so as to be vertically movable, and the guide portion 1
It projects downward through the lower end opening of 39a and is held so as not to fall off from the cylindrical guide portion 139a due to the annular locking collar 126a being caught by the step portion 140.

The first switch push rod 129 made of a synthetic resin such as polycarbonate has a head 129a at the upper end that is detachably hooked on the step 38a1 of the stepped cylindrical portion 38a, and has a small diameter at the lower end. It has a spring receiver mounting portion 129b. This switch push rod 12
Reference numeral 9 is provided so as to vertically move through the through hole 138 from the inside of the recess 135. First switch push rod 129
The vertical movement of the head 129a allows the head 129a to be removably fitted into and engaged with the head engaging portion 130a of the second switch push rod 130. Spring receiver mounting part 12
A spring receiving plate 153 having a washer shape is horizontally attached to 9b.

The stainless steel first coil spring 127 and the second coil spring 128 serve as an urging means for the floor surface detector 126 and the first switch push rod 129.
Specifically, the first coil spring 127 is provided on the floor surface detector 126.
The second coil spring 128 is sandwiched between the inner bottom surface of the spring and the spring bearing mounting portion 129b, and the second coil spring 128 has the lower end surface of the small diameter cylindrical portion of the stepped cylindrical portion 138a and the spring bearing mounting portion 129.
It is sandwiched between b and. These springs 127, 12
When the floor surface detector 126 detects the floor surface A, the reference numeral 8 urges the detector 126 downward and pushes up the first switch push rod 129. Second coil spring 1
28 has a smaller spring force and is thinner than the first coil spring 127.

The fall switch 121 of the above construction screwed to the bottom wall of the electric heater is shown in FIG. 11 (A) and FIG. 1 when the heater is lifted in a normal posture.
It is in the free state shown in 2.

In this state, the floor surface detector 126 is located on the floor surface and is not detecting the floor surface A.
Due to the biasing force of the second coil springs 127 and 128, the second coil springs 127 and 128 are projected to the maximum below the guide 139, and the annular locking collar 12
6a is hooked on the step 140 of the guide 139. As a result, the first switch push rod 129, which is lowered together with the floor surface detector 126, is lowered most so that the head 129a thereof does not project into the recess 135 and the through hole 13 is formed.
8 and is caught in and supported by the step portion 138a1 of the stepped cylindrical portion 138a.

Thus, the first switch push rod 129 is moved to the second
Since it is located below the switch push rod 130,
Due to its own weight, the second switch push rod 130 hangs in a state of standing vertically to the lowest portion of the support shaft 123. As a result, the second switch push rod 130 is arranged below the second switch contact piece 125 without pushing it up, in other words, without contacting the upper end of the second switch contact piece 125, and the head engaging portion 130a. It is arranged right above the through hole 138 so as to face it.

Therefore, both switch contacts 124, 12
The contacts 124a and 125a of the No. 5 are separated, and the overturn switch 121 is opened. FIG. 11B shows a state in which the electric heater is placed on the floor surface A in the correct use posture. In this state, since the floor surface detector 126 is pushed up by the floor surface A, the head 129a of the first switch push rod 129, which is raised together with the detector surface 126 via the first and second coil springs 127 and 128, passes. Hole 1
It is projected from 38 into the recess 135. As a result, first, the second head 129a that is just opposite to the second head
The switch push rod 130 is inserted into and engaged with the head engaging portion 130a, and both the switch push rods 129 and 130 are combined so as to become one switch push rod. Next, the first switch push rod 12 is maintained with this engagement state maintained.
9 vertically pushes up the second switch push rod 130. In this pushing up, the second switch push rod 130
By having the elongated hole 130b loosely fitted in the support shaft 3, the operation can be performed without being disturbed by the support shaft 123.

The second switch push rod 130 thus pushed up finally elastically deforms and holds the second switch contact piece 125, so that the movable contact 125a of this contact piece 125 fixes the first switch contact piece 124. Contact 12
4a is pressed and held. That is, the overturn switch 121 is held in the closed state, thereby enabling use of the electric heater.

At this time, the first and second coil springs 127,
All of 128 are compressed, but first, the second coil spring 128 having a small spring force is compressed. Then, the lower end surface of the small-diameter cylindrical portion of the stepped cylindrical portion 38 and the spring receiving attachment portion 129.
The first coil spring 127 is compressed after the second coil spring 128 closely contacts its coil wire with b. Therefore, the contact pressure of the contact points 124a and 125a is exclusively dependent on the spring force of the second coil spring 128, and the 7 spring force of the first coil spring 12 directly affects both switch push rods 129 ,.
It does not participate in the second switch contact piece 125 via 130.

Therefore, as in the case where the floor surface A is rugged, it fluctuates according to the length of the rug's hair.
As much as the spring force of the coil spring 128, the contact pressure does not fluctuate, the fluctuation of the contact pressure due to the state of the floor surface A can be prevented, and an excessive pushing force is applied to the second switch contact piece 125. It can be prevented. Moreover, for such a reason, a large stroke of the floor surface detector 126 can be secured, and the guide 13 as shown in FIG.
The length of protrusion from 9 can be reduced.

When the electric heater is overturned due to, for example, an earthquake during use of the electric heater, and the floor detector 126 of the overturn switch 121 receives the pushing force F, the overturn switch 121. The state of is
Is shown in

First, since the floor surface detector 126 does not detect the floor surface A as the electric heater falls, the detector 126 also simultaneously detects the first and second coil springs 127, 12.
The maximum force is projected from the tip of the guide 139 by the urging force of the guide 139, and the first switch push rod 129 moved accordingly is not projected into the recess 135, and
Immersed in 38. The state immediately after such a fall is shown in FIG.
This is the same as when (A) is in the horizontal position.

In this state, since the first switch push rod 129 does not restrain the second switch push rod 130, the push rod 130 is supported by its own weight in the posture of the concave portion 135 at that time depending on the fall posture. It is moved to the lowest position of the shaft 123, or is rotated around the axis of the support shaft 123 (see the chain double-dashed line in FIG. 11B and FIG. 13),
Or do these at the same time. As a result, the head engagement 130a of the second switch push rod 130 is located off the axial line of the first switch push rod 129.

Then, the pressing force applied to the second switch contact piece 125 by the second switch push bar 130, which relays the movement of the first switch push bar 130 toward the second switch contact piece 125, disappears. Therefore, since the second switch contact piece 125 elastically returns so as to be separated from the first switch contact piece 124, these contact points 124a and 125a are separated from each other, and the overturn switch 121 is opened to connect the power supply circuit of the electric heater. Turn off.

In such a fall state, as described above, at least the head engagement 1 of the second switch push rod 130 is performed.
Since 30a is located off the long axis of the first switch push rod 129, the floor force sensor 12 is moved by the external force F.
When 6 is pushed in, the second switch push rod 129 is moved accordingly, but the second switch member 129
The switch push rod 130 is not pushed.

Therefore, according to the tipping switch 21, the relay function disappears due to the retracting operation of the second switch pushing rod 130 due to its own weight as described above, so that the floor surface detector 126 is inadvertently pushed in in the tipping state. Contact 124
It is possible to reliably prevent the a and 125a from closing. As a result, it is possible to prevent the power supply from being turned on again when the electric heater including the tipping switch 121 falls, and it is possible to further enhance safety.

In addition, in the fourth embodiment, the first
The maximum pushing depth of the switch push rod 129 is such that when the coil wire of the second coil spring 128 comes into close contact with this spring 1
28 is determined as a spacer, and in this case, the first switch push rod 129 and the support shaft 123 are not in contact with each other. Therefore, if the electric heater is inverted upside down, the floor surface is detected. Even if the child 126 is pushed down, the fall switch 121 is not turned on again. It should be noted that the fourth embodiment can be implemented by omitting the second coil spring 128. In that case, if the electric heater is inverted upside down, the floor surface detector 126 is pushed down. However, since the support shaft 123 serves as a stopper to prevent the first switch push rod 129 from pressing the second switch contact piece 125, the overturn switch 121 is also used in this example.
Will never be re-introduced.

The present invention is not limited to the above embodiments. For example, the urging means for urging the switch push rod and the floor surface detector may be only one of the first coil spring and the second coil spring. Further, the present invention may be an invention in which a portable electric device including the fall switch described in each of the above-described embodiments is a new embodiment.

[0083]

The present invention described in detail above has the following effects. According to the overturn switch of the first aspect of the present invention, when the switch push rod receives the pushing force in the overturned state of the electric device including the switch, the switch push rod is pushed in the second switch contact piece direction. Since it is mechanically blocked by the push rod control weight, it is possible to reliably prevent the contacts from being closed even when the floor surface detector is pushed in in the overturned state.

According to the overturn switch of the second aspect of the present invention, since the second switch push rod is removed from the extension line of the axis line of the first switch push rod in the overturned state of the electric device equipped with this switch, the overturned state is obtained. In the case where the floor surface detector receives a pushing force, the first switch push rod does not push the second switch contact piece through the second switch push rod, so that the floor surface is kept in the overturned state. Even if the detector is pushed in, it is possible to reliably prevent the contacts from closing.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of an electric heater including a tipping switch according to a first embodiment of the present invention.

FIG. 2 is a front view showing the configuration around the tipping switch with the front case of the electric heater shown in FIG. 1 removed.

FIG. 3 is a perspective view showing a configuration of a tipping switch according to the first embodiment.

FIG. 4 is a plan view showing a configuration of a tipping switch according to the first embodiment.

FIG. 5 (A) shows the first state of the electric heater in a non-falling state.
FIG. 6 is a cross-sectional view showing the configuration of the tipping switch according to the embodiment of FIG. (B) is sectional drawing which shows the structure of the falling switch which concerns on 1st Embodiment in an ON state in the non-falling state of an electric heater.

FIG. 6 is a cross-sectional view showing the configuration of the overturn switch according to the first embodiment when the electric heater falls over.

FIG. 7A is a sectional view showing a configuration of a tipping switch according to a second embodiment of the present invention. FIG. 7B is a plan view showing the configuration of the recess of the main body included in the overturn switch according to the second embodiment.

FIG. 8A is a sectional view showing a configuration of a tipping switch according to a third embodiment of the present invention. FIG. 9B is a bottom view showing the configuration of the push rod control weight included in the tipping switch according to the third embodiment.

FIG. 9 is a perspective view showing a configuration of a tipping switch according to a fourth embodiment of the present invention.

FIG. 10 is a plan view showing a configuration of a tipping switch according to a fourth embodiment.

FIG. 11A is a cross-sectional view showing the configuration of the overturn switch according to the fourth embodiment in an off state in a non-overturned state of the electric heater. FIG. 9B is a cross-sectional view showing the configuration of the overturn switch according to the fourth embodiment in the ON state in the non-overturning state of the electric heater.

FIG. 12 is a cross-sectional view showing the configuration of the overturn switch according to the fourth embodiment in an off state in a non-overturning state of the electric heater.

FIG. 13 is a cross-sectional view showing the configuration of the overturn switch according to the fourth embodiment when the electric heater falls over.

FIG. 14 is a cross-sectional view showing a configuration of a tipping switch according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Electric heater (portable electric equipment), 21, 121 ... Fall switch, 22, 122 ... Fall switch body, 23 ... Lid, 24, 124 ... 1st switch contact piece, 24a, 124a ... Fixed contact, 25 , 125 ... Second switch contact piece, 25a, 125a ... Movable contact, 26, 126 ... Floor surface detector, 27, 127 ... First coil spring (urging means), 28, 128 ... Second coil spring (urging) Means), 29 ... Switch push rod, 30 ... Push rod control weight, 36, 135 ... Recessed portion, 38, 138 ... Main body through hole, 39, 139 ... Guide, 40 ... Lid through hole, 47 ... Center hole, 48 ... Surrounding stopper part, 123 ... Support shaft, 129 ... First switch push rod, 129a ... Head, 130 ... Second switch push rod, 130a ... Head engaging part, 130b ... Long hole, A ... Floor surface.

Claims (2)

[Claims] 1. A substantially inverted frusto-conical or hemispherical recess having an open upper surface, a through hole is provided in the center of the bottom wall of the recess, and the recess projects downward from the bottom of the recess. A main body having an installed guide, a lid having an upper surface opening attached to the concave portion and having a through hole in the central portion, and a fixed contact attached to the main body located above the concave portion and having a fixed contact. It has a first switch contact piece and a movable contact which is located between the first switch contact piece and the recess and which is attached to the main body and is brought into contact with and separated from the fixed contact, and is elastically deformable. And a second switch contact piece that holds the movable contact at a position away from the fixed contact due to its elastic deformation, a floor surface detector that is vertically movable along the guide, and a vertical switch together with this detector. Before being set up to move A switch push rod that passes through both through holes and the center of the recess and is brought into contact with and separated from the second switch contact piece from below, and when the floor surface detector detects the floor surface, the floor surface detector is moved downward. An energizing means for energizing and pushing up the switch push rod, and a central hole into which the switch push rod can be inserted are formed in a central portion and formed in a shape similar to the concave portion and smaller than the concave portion, and the concave portion is formed by its own weight. It is movably housed inside and is arranged so that the peripheral stopper portion of the central hole faces the both through holes by free movement when falling, and the central hole faces the both through holes in the non-falling state. Falling switch equipped with a push rod control weight that is arranged as a unit. 2. A main body having a recess having an open upper surface, a through hole provided in the center of the bottom wall of the recess, and a guide projecting downward in a continuous manner to the lower side of the recess. A first switch contact piece that is located above the recess and is attached to the body and has a fixed contact; and a first switch contact piece that is located between the first switch contact piece and the recess and is attached to the body, and A second switch contact piece that has a movable contact that is brought into contact with and separated from the fixed contact and that is elastically deformable and that holds the movable contact at a position apart from the fixed contact by its elasticity, and moves up and down along the guide. A freely installed floor detector, a first switch push rod that has a head at the upper end and is vertically movable by passing the head through the through hole, and moves vertically together with the floor detector. The floor inspection Urging means for urging the floor surface detector downward when the child detects the floor surface and pushing up the first switch push rod, the second switch contact piece and the through hole across the recess. And a head-engaging portion at the lower end, which is engageable with the head, and which has a substantially V-shaped support shaft that is bent so that an intermediate portion facing the through hole is the lowest. , An elongated hole extending in the longitudinal direction is provided on the upper side, the elongated hole is fitted to the support shaft, and is rotatable in the axial direction of the shaft by its own weight, and is elongated within the length range of the elongated hole. Is mounted so as to be movable in any direction, and is arranged so as to deviate from the extension of the axis line of the first switch push rod by free movement at the time of falling, and in the non-falling state, it is arranged to stand right above the first switch push rod. Upward movement of the first switch push rod Fall switch and a second switch pushrod relayed to the second switch contact piece a.