JPH05274987A - Thermal relay - Google Patents

Abstract

PURPOSE:To provide a thermal relay in which the operating characteristics of a reversing mechanism portion can be adjusted. CONSTITUTION:The displacement of a thermal element which displaces in proportion to the amount of electricity is transmitted to a contact device via a reversing mechanism portion 31 which performs tripping action. In the reversing mechanism portion 31, if a first reversing plate 34 is exerted with a pushing force caused by the displacement of the thermal element, when a second reversing plate 35 is located in one of stable positions, a reversing spring 36 exceeds its dead point and the second reversing plate 35 moves to the other stable position. A bias spring 30 exerting a restoring force on the first reversing plate 34 in the direction in which to locate the second reversing plate 35 in one of the stable positions is inserted between a frame 33 and the first reversing plate 34. One end portion of the bias spring 30 is fitted into the spring support hole 33f of the frame 33 and this fitting position can be adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal relay in which a contact device is driven by a thermal element that is displaced in accordance with the amount of electricity supplied.

[0002]

2. Description of the Related Art Conventionally, in this type of thermal relay, a trip device is provided for transmitting the displacement of a thermal element having a bimetal or the like to a contact device. In other words, the thermal element is displaced according to the amount of energization, and when an overcurrent flows and the amount of displacement of the thermal element reaches a predetermined threshold value, the trip device operates to open and close the contact device. Invert. The trip device adjusts the correspondence between the inversion mechanism that drives the contact device and the displacement of the thermal element and the operating point of the inversion mechanism. And an operating point adjusting mechanism section for adjusting (threshold value).

As shown in FIGS. 25 and 26, the reversing mechanism portion includes a first reversing plate 34 and a second reversing plate 34 that are swingably held with respect to a frame 33 fixed at a fixed position of the body. A second plate which is formed by connecting the reversing plate 35 via a reversing spring 36 and swings between two defined stable positions.
The contact device is opened and closed in accordance with the swing of the reversal plate 35. The reversing spring 36 is a tension spring, and has ring-shaped hooking portions 36a formed at respective ends with respect to hooking holes 34a and 35a penetrating the first reversing plate 34 and the second reversing plate 35, respectively. Insert the first reversal plate 3
4 and a second reversing plate 35. Therefore, when the first reversing plate 34 receives the pressing force F ₁ associated with the displacement of the thermal element via the operating point adjusting mechanism portion when the second reversing plate 35 is positioned at one stable position, FIG. As shown in, the second reversing plate 3 is moved along with the movement of the first reversing plate 34.
Inversion spring 3 centered on the point p ₁ of the spring force acting on 5
The center line of 6 moves. Here, if the center line of the reversing spring 36 moves beyond a straight line (dead point) that connects the fulcrum portion p ₂ of the second reversing plate 35 and the point of action p ₁ of the spring force on the second reversing plate 35, , The second reversing plate 35 rapidly moves to the other stable position by the so-called trip operation, and FIG.
The state shifts to the state of FIG. 25 (b). In this way, the open / closed state of the contact device is reversed by receiving the pressing force when the position of the second reversing plate 35 is reversed.

By the way, in this type of thermal relay,
After the thermal element is displaced by the overcurrent, when the thermal element returns to its original position, the first reversing plate 34 and the second reversing plate 35 of the reversing mechanism unit are returned to their original positions in preparation for the next operation. It is necessary to return to the position. In order to automate such a returning operation, a card for transmitting the movement of the second reversing plate 35 to the contact device is provided, and the moving range of the card is regulated so that the second reversing plate 35 does not reach the stable position. It is thought to do.

[0005]

In the above configuration, if the position for restricting the card is fixed, the returning operation may not be performed due to the variation in the operation of the reversing mechanism. That is, the position of the card is restricted at the position X shown in FIG.
Assuming stable position of the second reverse plate 35 varies in a range Y shown in FIG. 2, the card is a second reverse plate 35 is present in the range Y ₁ beyond the dead point before being restricted by the position X Therefore, if the reversing mechanism operates in the range Y ₁ , there is a problem that the returning operation cannot be automated. The solid line in FIG. 2 shows the case where the return operation cannot be automated. Since the position where the second reversing plate 35 exceeds the dead point is point A, the position X
Even if the movement of the card is restricted by, the second reversing plate 35 is stabilized toward the operating position and does not return to the initial position.

In order to solve such a problem, it is possible to prepare a plurality of types of cards that can be used to regulate the movement range at different positions and select the card according to the operation specification of the reversing mechanism. It is considered. However,
In such a configuration, there is a problem that a card having a plurality of types of specifications is required for the same part, the assembly work is troublesome, and part management becomes complicated.

An object of the present invention is to solve the above-mentioned problems, and it is possible to absorb the variation in the operation of the reversing mechanism section without using parts having different specifications, and at the time of restoration of the thermal element, the reversing mechanism section. It is intended to provide a thermal relay capable of surely automatically returning.

[0008]

According to the present invention, in order to achieve the above object, a thermal element that is displaced in accordance with the amount of energization,
The first reversing plate and the second reversing plate, which are respectively swingably held with respect to the frame fixed to the fixed position of the body, are interlocked with each other via a reversing spring, and the swinging range of the second reversing plate is adjusted. Two
A reversing mechanism portion regulated between two stable positions, and an actuating plate that exerts a pressing force on the first reversing plate according to the displacement of the thermal element when the second reversing plate is positioned at one stable position. And a contact device that is opened / closed in accordance with the swing of the second reversing plate, the reversing mechanism portion includes a first reversing mechanism when the second reversing plate is located at one stable position. When the plate receives a pressing force from the actuating plate due to the displacement of the thermal element, the center line of the reversing spring moves around the point of application of the spring force on the second reversing plate and the fulcrum portion of the second reversing plate. The second reversing plate is configured to move rapidly to the other stable position when it crosses a straight line connecting the point of action of the spring force to the second reversing plate and the second reversing plate. A bias that applies a restoring force to the first reversing plate in the direction to position it at one stable position When it is provided with a bias adjusting means for adjusting the return force by the bias spring.

[0009]

According to the above construction, since the first reversing plate is provided with the bias adjusting means for exerting the returning force by the bias spring and adjusting the returning force by the bias spring, the operation of the reversing mechanism portion is prevented. It can be adjusted. Therefore, the variation of the spring force of the reversing spring and the like can be absorbed only by the reversing mechanism section, and it is not necessary to prepare a plurality of types of parts having different specifications. That is, when the reversing mechanism is automatically returned when the thermal element is restored, variations in the operation of the reversing mechanism can be absorbed by the bias spring and the bias adjusting means.

[0010]

【Example】

(Embodiment 1) As shown in FIG. 3, FIG. 4, FIG. 5, etc., a body 1 has a body 11 having an opening on one side, a cover 12 for closing the opening of the body 11, and a part of the body 11. Formed by an inner lid 6 interposed between the body 11 and the cover 12, and by assembling the assembly screw 14 through the cover 12 to the boss 13 formed on the body 11, The cover 12 is joined. Figure 7
As shown in FIG.
By being engaged with the perforated engagement piece 12a provided on the cover 12, the coupling strength between the body 11 and the cover 12 is enhanced.

The inside of the body 11 is roughly divided into three sections 16a, 16b, 16c by the partition wall 15. The second section 16b is formed on one side of the body 1 over substantially the entire length in the vertical direction in FIG.
6a and the 3rd division 16c are arranged up and down in Drawing 3. The first section 16a is further divided into three chambers by the partition wall 15 in the vertical direction of FIG.
The thermal element 2 is housed in each of the other two chambers except the central chamber. The thermal element 2 is obtained by spirally winding a belt-shaped heater 23 around a bimetal 21 formed in a rectangular plate shape with an insulating material 22 in between. One end of the heater 23 is welded to one end of the bimetal 21. It is fixed by the method such as. The bimetal 21 is a partition wall 1 that divides the first compartment 16a into three chambers.
The bimetal 21 is arranged so as to be in parallel with 5, and is deformed in the thickness direction of the partition wall 15 when heated. The other end of the bimetal 21 and the other end of the heater 23 are fixed to the terminal plates 24 and 25, respectively.

The terminal plate 24 is made of a metal plate and is arranged along the inner surface of the bottom wall of the body 11 and has a fixing piece 24a.
A connecting piece 24b which is arranged so as to project from the inner surface of the bottom wall of the body 11 and is continuous with the fixing piece 24a; and a connecting piece 24b which is arranged so as to penetrate the bottom wall of the body 11 and is integrally formed with the fixing piece 24b. And a continuous terminal piece 24c. Fixed piece 2
A screw hole 24d is formed in 4a, and as shown in FIG.
The terminal plate 24 is fixed to the body 11 by a fixing screw 26 that is screwed into the screw hole 24d through the bottom wall of the body 11. The other end of the bimetal 21 is fixed to the connecting piece 24b by welding or the like. In the terminal piece 24c,
A screw hole 24e is formed so that the terminal screw 27 having a washer 27a can be screwed.

On the other hand, the terminal plate 25 has a shape in which a connection piece 25a substantially parallel to the bimetal 21 and a terminal piece 25b protruding from the body 1 through the cover 12 are integrally continuous. The other end of the heater 23 is fixed to the connecting piece 25a by a method such as welding. Also, the connecting piece 25
The staircase portion 25c is formed in a, and a part of the connecting piece 25a protrudes outward from the opening surface of the body 11 and the third section 16a.
It is designed to straddle c.

A terminal plate 28 in which the connecting pieces 24b and 25a of the terminal plate 24 and the terminal plate 25 are integrally connected to each other is provided in one chamber at the center of the first compartment 16a. That is, the terminal plate 28 includes a terminal piece 28a protruding from the body 1 through the bottom wall of the body 11 and a terminal piece 28b protruding from the body 1 through the cover 12, and both terminal pieces 28a, 28b.
Are connected together. In the terminal piece 28a,
A screw hole 28c is formed so that the terminal screw 27 having a washer 27a can be screwed.

On the outer surface of the body 11, each terminal piece 2
The terminal pieces 24c, 2
A partition wall 11b is provided so as to isolate 8a (see FIG. 8). In the cover 12, the terminal pieces 25b,
A holding wall 12b is provided at a portion where 28b projects,
Rattling of the terminal pieces 25b and 28b is prevented. According to the above configuration, when electricity is applied between the terminal piece 24c and the terminal piece 25b, a current flows through the bimetal 21 and the heater 23. Due to the self-heating of the bimetal 21 and the heating of the heater 23, the bimetal 21 is heated. The one end is displaced in the thickness direction of the bimetal 21 with respect to the other end. The direction of displacement is such that the one end approaches the second section 16b, and the amount of displacement depends on the amount of heat generated by the bimetal 21 and the heater 23.

Partition wall 1 for dividing the first compartment 16a into three chambers
5, and the partition wall 15 that partitions the first section 16a and the second section 16b is provided with a slit 15a at a position corresponding to the one end of the bimetal 21, and moves in a direction orthogonal to the opening surface of the slit 15a. The interlocking plate 17 is arranged so as to be free. The interlocking plate 17 has three leg pieces 1.
7a is integrally connected via a connecting piece 17b, and is formed in a substantially E shape. When at least one bimetal 21 is deformed, the leg piece 17a is pressed and the second end portion of the interlocking plate 17 is
The amount of protrusion into the section 16b is increased. A pushing piece 17c is projectingly provided on the leg piece 17a protruding to the second section 16b. Further, the interlocking plate 17 has a play in the moving direction with respect to the bimetal 21, and when one bimetal 21 is deformed, it can be moved without deforming the other bimetal 21.

The trip device 3 is housed in the second compartment 16b. The trip device 3 includes a reversing mechanism section 31 and an operating point adjusting mechanism section 32. The reversing mechanism section 31 is shown in FIG.
As shown in FIG. 3, the first reversing plate 34 and the second reversing plate 35 are swingably attached to the frame 33 fixed to the body 11, and the first reversing plate 34 and the second reversing plate 35 are attached. And a reversing spring 3 which is a tension spring composed of a coil spring.
It has the structure connected through 6. Frame 33
Is a press-fitting piece 33a that is press-fitted into a mounting hole 18 (see FIG. 9) formed in the body 11, and a substantially V-shaped notch groove 33d, 3
Arm pieces 33b and 33c having 3e. The first reversing plate 34 and the second reversing plate 35 are respectively provided with the cutout grooves 3.
By inserting one end into 3d and 33e, the other end is supported so as to be swingable in the thickness direction of the frame 33. Further, the notch grooves 33d and 33e are opened so as to be apart from each other, and are retained on the frame 33 by applying a tensile force between the first reversing plate 34 and the second reversing plate 35 via a reversing spring 36. It is supposed to be done. The reversing spring 36 has ring-shaped hooks 36 at both ends.
a, the first reversing plate 34 and the second reversing plate 35 are formed by inserting the respective hooking portions 36a into the hooking holes 34a, 35a penetrating the first reversing plate 34 and the second reversing plate 35. 35
Connected to.

Between the frame 33 and the first reversing plate 34, a bias spring 3 composed of a coil spring for biasing the tip of the first reversing plate 34 in a direction away from the frame 33.
0 is allocated. That is, the restoring force acts on the first reversing plate 34, and as a result, the restoring force also acts on the second reversing plate 35. The frame 33 has a spring support hole 33f to which one end of the bias spring 30 is attached.
Are formed. The spring support hole 33f is formed so that the three circles partially overlap each other so that one end of the bias spring 30 can be held at three positions in the arrangement direction of the first reversing plate 34 and the second reversing plate 35. It is formed in a shape connected to. Therefore, the mounting position of the bias spring 30 is 3
It is possible to select the position, and it is possible to adjust the distance between the acting point of the spring force of the bias spring 30 and the fulcrum portion of the first fulcrum plate 34 according to the mounting position of the bias spring 30. That is, the restoring force acting on the first fulcrum plate 34 can be adjusted, and the spring support hole 33f functions as bias adjusting means.

In the reversing mechanism 31, the second reversing plate 3
5 is moved in the thickness direction of the frame 33 in a direction away from the frame 33, the reversing spring 36
When the center line of the second reversing plate 35 is located on the opposite side of the frame 33 beyond the straight line connecting the connecting portion of the second reversing plate 35 with the reversing spring 36 and the fulcrum of the second reversing plate 35 with respect to the frame 33, The spring force of the reversing spring 36 acts in a direction in which the tip end portion of the second reversing plate 35 is separated from the frame 33. Therefore, the tip of the second reversing plate 35 is held at a position apart from the frame 33 in the thickness direction of the frame 33 (hereinafter, this position is referred to as a reset position). Further, the tip of the second reversing plate 35 is attached to the frame 33.
When the intermediate portion of the first reversing plate 34 is pressed in a direction of approaching the frame 33, the center line of the reversing spring 36 reverses in the second reversing plate 35 in the state of being separated from the frame 33 in the thickness direction of Second connection with spring 36 and second
When it comes to the position close to the frame 33 beyond the straight line connecting the reversing plate 35 with the fulcrum of the reversing plate 35 with respect to the frame 33, the spring force of the reversing spring 36 acts so that the tip of the second reversing plate 35 approaches the frame 33. Then, the second reversing plate 35
Is rapidly moved toward the frame 33. That is, a so-called trip operation is performed and the second reversing plate 35
Of the frame 3 in the thickness direction of the frame 33.
It is held at a position close to 3 (this position is hereinafter referred to as a trip position).

The operating point adjusting mechanism 32 is constructed as shown in FIG. 10, and is rotatably attached to a shaft projection 19 (see FIG. 3) provided on the body 11 in a direction orthogonal to the bottom wall. The rotary lever 37 is attached to the rotary lever 37. The operating plate 38 is swingably held by the rotary lever 37. The operating point adjusting cam 39a is rotatably attached to the peripheral wall of the body 11. ..

The turning lever 37 has a substantially U-shaped lever body 37c in which a pair of parallel leg pieces 37a are connected to each other via a pair of connecting pieces 37b. A bearing hole 37d to be inserted is formed, and the other leg piece 37a is formed with an arc-shaped bearing recess 37e that abuts the peripheral surface of the shaft projection 19. One connecting piece 37b of the lever body 37c is substantially T-shaped, and a holding piece 37f is formed in a shape substantially orthogonal to the T-shaped leg portion, and the operating plate 38 is swingably held by the holding piece 37f. The holding hole 37g is formed. The holding hole 37g has a substantially rectangular shape as shown in FIG. 11, and has a holding recess 37h formed on one side of the connecting piece 37b. Further, a holding protrusion 37i is provided so as to face the holding recess 37h at the inner peripheral edge of the holding hole 37g. The leg piece 37a provided with the bearing hole 37d extends to the side opposite to the holding piece 37f with respect to the bearing hole 37d, and the tip end of the leg piece 37a has an adjusting piece 37j in the same plane as the connecting piece 37b. Is formed.

The operating plate 38 has cutout grooves 3 on both side edges of the intermediate portion.
8a. This operating plate 38 is provided with a rotating lever 37.
Of the holding hole 37g, and both side portions of the holding recess 37h of the holding hole 37g are fitted into the notch grooves 38a. That is, by fitting a part of the operating plate 38 into the holding recess 37h, the movement of the operating plate 38 in the longitudinal direction and the width direction is restricted. Further, in order to restrict the movement of the operating plate 38 in the thickness direction, the distance between the bottom surface of the holding recess 37h and the tip end surface of the holding protrusion 37i is set to be slightly larger than the thickness of the operating plate 38 in FIG. ) Actuating plate 3
After inserting 8 into the holding hole 37g, as shown in FIG. 12B, one side of the peripheral portion of the holding hole 37g provided with the holding protrusion 37i is plastically deformed by a method such as tapping. Here, as shown in FIG. 13, the swing range θ of the operating plate 38 with respect to the turning lever 37 is restricted by the distance between the bottom surface of the holding recess 37h and the holding projection 37i. That is, as shown in FIG. 14, the operating plate 38 swings only in the range corresponding to the gap between the bottom surface of the holding recess 37h and the tip surface of the holding projection 37i. Working plate 38
Is disposed at a position where it can contact the pushing piece 17c of the interlocking plate 17, and the other end is disposed at a position where it can contact the first reversing plate 34. That is, when the interlocking plate 17 moves due to the deformation of the thermal element 2, the operating plate 38 is pressed by the interlocking plate 17 and rotates around the holding hole 37g, and presses the first reversing plate 34 toward the frame 33. Of.

On the other hand, as shown in FIG. 3, the operating point adjusting cam 39 has a columnar leg portion 39a, a flange portion 39b provided at one end of the leg portion 39a, and a protrusion at the other end of the leg portion 39a. And a cam projection 39c. The leg 39a is the body 1
The flange portion 39b is inserted into the through hole 11c formed in the peripheral wall of the body 1, and the flange portion 39b abuts the outer surface of the body 11. A cross-shaped driver groove 39f is formed in the center of the portion of the operating point adjustment cam 39 exposed on the outer surface of the body 11 so that the tip of a plus driver can be inserted. The adjusting cam 39 can be rotated. Further, a protective wall 11d surrounding the peripheral edge of the flange portion 39b is formed on the outer surface of the peripheral wall of the body 11, so that the operating point adjusting cam 39 may be carelessly rotated when another member touches the outer peripheral edge of the flange portion 39b. To prevent. A groove 39d is formed over the entire circumference of the leg 39a, and a holding spring 39e is mounted between the leg 39a and the holding groove 11e formed on the inner circumferential surface of the peripheral wall of the body 11. In addition, the leg 3 is provided at a portion of the body 11 facing the holding spring 39e.
The holding wall 11f with which 9a abuts is formed, and the holding spring 39
The operating point adjusting cam 39 is prevented from coming off from the body 11 by sandwiching the leg portion 39a between e and the holding wall 11f.

The cam projection 39c is provided eccentrically with respect to the rotation center of the leg portion 39a at a position where the adjusting piece 37j of the turning lever 37 can come into contact. Therefore, by rotating the operating point adjustment cam 39, the rotation range of the rotation lever 37 around the shaft protrusion 19 can be adjusted.
Further, since the swing range of the operating plate 38 with respect to the rotating lever 37 is restricted, when the first reversing plate 34 receives a pressing force from the operating plate 38 by rotating the operating point adjusting cam 39. It is possible to change the deformation amount of the thermal element 2. That is, when the interlocking plate 17 moves due to the deformation of the thermal element 2, the operating plate 38 is pressed, but the operating plate 38 is received from the interlocking plate 17 until the adjustment piece 37j of the rotating lever 37 contacts the cam projection 39c. The pressing force is
It only rotates the rotating lever 37 (rotates clockwise in FIG. 6) and does not act on the first reversing plate 34 of the reversing mechanism section 31. On the other hand, when the adjusting piece 37j of the rotating lever 37 comes into contact with the cam protrusion 39c, the rotating lever 37 cannot rotate, so that the interlocking plate 17 moves to the operating plate 3c.
The pressing force acting on 8 is transmitted to the first reversing plate 34. With such a configuration, the amount of deformation of the thermal element 2 required to reverse to the trip position when the reversing mechanism portion 31 is at the reset position can be adjusted by the rotational position of the operating point adjusting cam 39. .. That is, the sensitivity is adjusted by rotating the operating point adjustment cam 39.

The contact device 4 includes a second section 16b and a third section 16b.
It is arranged across the section 16c. The contact device 4 includes a pair of movable spring plates 41a, 42a and the movable spring plates 41a,
A pair of fixing plates 43a and 44a corresponding to 42a, respectively.
It has and. The movable spring plates 41a and 42a and the fixed plates 43a and 44a are terminal plates 41b, 42b and 43 arranged so as to penetrate the bottom wall of the body 11, respectively.
It is fixed to b and 44b. Each terminal board 41b, 42b, 4
3b and 44b are screw holes 41c, 42c, 43c and 44 into which terminal screws 45 having washers 45a are screwed.
c is formed. Each terminal board 41 is provided on the outer surface of the body 1.
The spaces b, 42b, 43b, 44b are separated by a partition wall 11b, as shown in FIG. Each movable spring plate 41
On the a and 42a and the fixed plates 43a and 44a, elongated contacts are provided in a substantially orthogonal shape. Further, each movable spring plate 41a, 42a has a spring force so as to contact the corresponding fixed plate 43a, 44a when no external force is applied.

The movable spring plates 41a and 41b are provided with a reversing mechanism 31 through a card 46 made of an insulating synthetic resin.
Is connected to the second reversing plate 35. The card 46 is
The slits 15b and 15c formed in the partition wall 15 are slidably arranged so that both ends are inserted, and are arranged so as to straddle the second section 16b and the third section 16c through the slit 15b. As shown in FIG. 15, the card 4
6, a notch groove 46a with which the second reversing plate 35 engages and a notch groove 46b with which one of the movable spring plates 41a engages are formed at one end inserted into the second section 16b. .. Further, a wide cutout groove 46c through which each movable spring plate 41b is inserted is formed in a portion of the card 46 arranged in the third section 16c. Therefore, as the second reversing plate 35 of the reversing mechanism 31 swings, the card 46
Slides, and the card 46 moves the movable spring plate 41a,
42a swings. Stopper projections 46d and 46e, which can abut against the peripheral portions of the slits 15b and 15c, are provided on both peripheral portions of the wide cutout groove 46c in the sliding direction of the card 46. When one of the stopper protrusions 46d and 46e contacts the peripheral edge of the corresponding slit 15b and 15c, the moving range of the card 46 is regulated. That is, both stopper protrusions 46d and 46e are formed in both slits 1.
5b and 15c are formed between both slits 15b and 15c.
The distance corresponding to the difference between the distance between c and the distance between both stopper protrusions 46d and 46e is the movable distance of the card 46. At the position where the reversing mechanism 31 is at the reset position and the card 46 is moved toward the second partition 16b side in the sliding direction, the movable spring plate 41a contacts the fixed plate 43a, and the movable spring plate 42a forms the peripheral edge of the cutout groove 46c. It is pressed by and is separated from the fixed plate 44a. Further, when the reversing mechanism portion 31 is at the trip position and the card 46 is moved toward the third partition 16c side in the sliding direction, the movable spring plate 4 is moved.
2a contacts the fixed plate 44a, and the movable spring plate 41a is pressed against the peripheral edge of the notch groove 46b and separated from the fixed plate 43a.
In short, the movable spring plates 41a and 42a are opened and closed with respect to the corresponding fixed plates 43a and 44a.

The card 46 is provided with a test piece 46f projecting to the outside of the body 1 through the cover 12. By operating the test piece 46f with a driver or the like, the operation regarding the open / closed state of the contact device 4 is performed. You are ready to test. In addition, as shown in FIGS. 8 and 16, a concave step portion 11g surrounded by three surfaces is formed on the outer surface of the body 11 at a portion corresponding to one end edge of the card 46 on the side of the third partition 16c.
Is formed, and a part of the card 46 is movably inserted into a corner portion formed by two surfaces orthogonal to the card 46 among the three surfaces surrounding the recessed step portion 11g. That is, as the card 46 slides, the exposure amount of the card 46 to the concave step portion 11g changes. Here, the shape of the concave step portion 11g is set so that the card 46 is barely exposed to the concave step portion 11g when the reversing mechanism portion 31 is located at the reset position. Also, the body 1 is black,
By making the card 46 yellow or the like so that the body 1 and the card 46 can be easily identified,
The position can be confirmed easily. in short,
The operating state of the reversing mechanism 31 and the open / closed state of the contact device 4 can be confirmed by observing the amount of protrusion of the card 46 into the recessed step portion 11g.

The body 11 is provided with a reset button 5 for returning the reversing mechanism 31 to the reset position via the card 46 by pushing the body 11 toward the body 11 when the reversing mechanism 31 is at the trip position. Be done. The reset button 5 is formed in a shape in which a leg portion 5b is projected from one end surface of a cylindrical head portion 5a, and a disc-shaped collar portion 5c is provided in an intermediate portion of the leg portion 5b. In the body 11, a part of an outer wall parallel to the card 46 and a surface facing the cover 12 are opened, and a recess 5 having a partition wall 52 parallel to the card 46 is formed.
1 is formed. The peripheral edge of the slit groove 53 formed in the partition wall 52 of the recess 51 is sandwiched between the flange portion 5c and one end edge of a return spring 54 made of a coil spring inserted in the leg portion 5b of the reset button 5. By doing so, the reset button 5 is biased by the return spring 54 so that the head portion 5 a projects to the outer surface of the body 11. Therefore, in the reset button 5, the return spring 54 has the head 5a and the recess 5
The maximum compression position with the first partition wall 52 (the position most pushed into the body 11) and the collar portion 5c.
Can be moved back and forth between the position where it contacts the partition wall 52 of the recess 51 (the position most protruding from the body 11).

Of the peripheral wall of the recess 51, a peripheral wall that is parallel to the card 46 and is the outer wall of the body 11 is formed with a notch 55 that is open to the cover 12 side, and the peripheral edge of the notch 55 faces the cover 12. A semi-circular recessed notch 56 is formed in the center of the peripheral edge. Further, inside the recess 51, as shown in FIG. 17, a stopper rib 57 and a guide rib 58 are formed. The stopper rib 57 runs in a direction substantially orthogonal to the card 46, and the guide rib 5
8 is formed so that a portion formed in parallel to a part of the stopper rib 57 and a portion formed apart from the outer wall of the body 11 so as to be parallel to the card 46 are continuous. An end edge of a portion of the guide rib 58 parallel to the card 46 is formed in a shape along the opening edge of the cutout recess 56.

By the way, the inner lid 6 which is sandwiched between the partition wall 15 of the body 11 and the cover 12 is arranged at a portion corresponding to the third section 16c. Positioning holes 61 are formed in two places in the inner lid 6, and the positioning protrusions 15 d projectingly provided on the tip end surface of the partition wall 15 are inserted into the positioning holes 61, whereby the inner lid 6 is positioned with respect to the body 11. Done. As shown in FIG. 18, a holding wall 62 that holds a part of each terminal plate 25, 28 is formed on the surface of the inner lid 6 facing the cover 12. Further, as shown in FIG. 19, the inner lid 6 is integrally formed with a first protrusion 63 which is inserted into the recess 51 and a second protrusion 64 which is inserted into the third partition 16c. .. The first protrusion 63 and the second protrusion 64 are separated by the partition wall 52 of the recess 51. The first protrusion 63 is formed in a shape that fills the portion of the notch 51 excluding the notch recess 56, and the surface facing the notch recess 56 is a circle together with the notch recess 56 and forms the reset button 5. It is formed in a semicircular cross section so as to hold the head portion 5a. The first protrusion 63 is integrally formed with a protrusion wall 65 that protrudes to the outer surface of the body 11 along the outer peripheral surface of the head portion 5a of the reset button 5. The protruding amount of the protruding wall 65 from the body 11 is set to be substantially equal to the maximum protruding amount of the reset button 5 from the body 11, and surrounds a half circumference of the head portion 5a of the reset button 5. Therefore, the presence of the projecting wall 65 prevents other members from accidentally coming into contact with the reset button 5. A window hole 66 is formed in an intermediate portion of the projecting wall 65 in the circumferential direction, and a part of the window hole 66 is integrally connected to the first projecting base 63 and a part of the projecting wall 65 is inside the projecting wall 65. A guide piece 67 that projects inward from the peripheral surface is provided. Guide piece 6
7 is connected to the first protrusion 63 so that it can be broken off relatively easily. The front end surface of the second protrusion 64 is configured so that the collar portion 5c of the reset button 5 abuts and slides.
It has a semicircular cross section. Therefore, the reset button 5 includes the slit groove 53, the notch recess 56, the first protrusion 63,
It is held by the second protrusion 64 and the like so as to be able to move forward and backward without swinging.

The peripheral surface of the head 5a of the reset button 5 is shown in FIG.
As shown in 0, a guide protrusion 5e is provided so as to project, and the guide protrusion 5e is arranged so as to be movable only along the guide rib 58. That is, the guide protrusion 5e can move only between the stopper rib 57 and the guide rib 58 and between the guide rib 58 and the bottom wall of the recess 51. The guide protrusion 5e is formed by the stopper rib 57 and the guide rib 5.
If the guide projection 5e is located between the guide rib 58 and the bottom wall of the recess 51, the reset button 5 moves forward and backward if it is located between the guide rib 5e and the bottom wall of the recess 51. 5 can rotate, but is restricted to be pushed into the body 11 by the guide ribs 58, so that it can hardly move back and forth. Further, the range of rotation is between a position in contact with the stopper rib 57 (hereinafter referred to as a manual reset position) and a position in contact with the tip surface of the first protrusion 63 (hereinafter referred to as an automatic reset position). It is regulated in the range of about 90 degrees.

An inclined surface 5d is formed at the tip of the leg portion 5b of the reset button 5 (see FIG. 3). The inclined surface 5d is inclined in the sliding direction of the card 46 at the manual reset position, and is inclined so that the trip position side of the reversing mechanism portion 31 projects more than the reset position side. Now, when the reversing mechanism portion 31 is at the trip position, the notch groove 46c of the card 46 is pushed by pushing the reset button 5.
Since the inclined surface 5d is in contact with the peripheral edge of the
The card 46 is moved by the pressing force received from, and the reversing mechanism portion 31 is reversed to the reset position.
On the other hand, the inclined surface 5d has the card 46 in the automatic reset position.
Inclining in a direction substantially orthogonal to the sliding direction of the reset button 5 in this state, when the reversing mechanism portion 31 tries to move to the trip position, the reset button 5
When the leg portions 5b of the card abut, the moving range of the card 46 is regulated so that the trip position is not held.
That is, the movable spring plate 42 is provided only while the pressing force from the operating plate 38 is acting on the first reversing plate 34 of the reversing mechanism section 31.
When a is brought into contact with the fixed plate 44a and the pressing force on the first reversing plate 34 is removed, the movable spring plate 41a moves to the fixed plate 43a.
It automatically returns to the state of contact with. In short, the operation is stable only at the reset position, and monostable operation is performed. Here, assuming that the movement range of the card 46 is restricted at the position X in FIG. 2, before the position of the card 46 is restricted by the variation of the operating characteristics of the reversing mechanism portion 31 as shown by the solid line in the conventional configuration. In some cases, the second reversing plate 35 crossed the dead point and became a bistable operation. However, if the mounting position of the bias spring 30 is adjusted within the range of the spring support hole 33f, as shown by the broken line in FIG. In addition, the movement of the card 46 can be restricted before the second reversing plate 35 crosses the dead center, and as a result, the returning operation can be automatically performed. As described above, since the variation in the operating characteristics is absorbed by adjusting the mounting position of the bias spring 30 provided in the reversing mechanism portion 31, it is not necessary to provide a component having a plurality of types of specifications.

In the head 5a of the reset button 5, the guide groove 5 into which the guide piece 67 is inserted at the manual reset position.
f is formed. The guide groove 5f is formed along the forward / backward direction of the reset button 5, and the guide piece 67 is formed in the guide groove 5f.
In the state where the reset button 5 is inserted into f, movement of the reset button 5 is restricted so that it can only move forward and backward. That is, the guide piece 6
When 7 is present, the automatic reset position cannot be set. Since it can be manually reset in the normal use state, the function is not hindered. Since the guide piece 67 can be relatively easily broken off, if it is necessary to move the reset button 5 to the automatic reset position, the guide piece 67 may be broken off. A driver groove 5g is formed on the front end surface of the head 5a of the reset button 5 so that a plus driver can be inserted, and the reset button 5 can be pushed and rotated using a driver or the like. ..

(Embodiment 2) In this embodiment, as shown in FIG. 21, the bias spring 30 is formed of a leaf spring. A substantially L-shaped hooking piece 30a is connected to one end of the bias spring 30, and three hooking pieces 30a are formed on the side of the frame 33.
It is adapted to engage with g. The tip of the bias spring 30 is bent so as to elastically contact the first reversing plate 34.
A pressing piece 30b is provided on the side edge of the one end of the bias spring 30.
Are provided so that the wobbling of the bias spring 30 is suppressed.

Also in the structure of this embodiment, by selecting which hooking groove 33g the hooking piece 30a of the bias spring 30 is engaged with, the restoring force acting on the first reversing plate 34 can be adjusted. As a result, variations in the operating characteristics of the reversing mechanism section 31 can be absorbed. That is, the hooking groove 33g functions as a bias adjusting means. Other configurations are similar to those of the first embodiment.

(Embodiment 3) In this embodiment, as shown in FIG. 22, a bias spring 30 made of a coil spring is used, and a spring receiving plate 30c is provided on the surface of the bias spring 30 that abuts against the first reversing plate 34. , And an adjusting screw 34b which is screwed to the first reversing plate 34 and abuts on the spring receiving plate 30c is provided as a bias adjusting means. In the bias spring 30, the spring receiving plate 30c
The end portion on the side opposite to is held in a circular spring holding hole 33h formed in the frame 33.

According to this structure, as shown in FIG. 22 (b), a part of the spring receiving plate 30c abuts on the first reversing plate 34, and the other part abuts on the tip of the adjusting screw 34b. Therefore, if the adjusting screw 34b is moved back and forth, the spring force acting on the first reversing plate 34 from the bias spring 30 can be adjusted, and as a result, the operating characteristics of the reversing mechanism portion 31 can be adjusted. .. Other configurations are similar to those of the first embodiment.

(Embodiment 4) In this embodiment, as shown in FIG. 23, a leaf spring is used as the bias spring 30, and two adjusting screws 34c,
34d are screwed together, and both adjustment screws 34c,
The tip of 34d contacts the bias spring 30. One end of the bias spring 30 is fixed to the frame 33 by caulking or welding.

In this configuration, the two adjusting screws 34c, 3
The spring force acting on the first reversing plate 34 from the bias spring 30 can be adjusted by advancing and retracting 4d, and the adjusting screws 34c and 34d function as bias adjusting means. Other configurations are similar to those of the first embodiment. (Embodiment 5) In this embodiment, as shown in FIG. 24, a leaf spring is used as the bias spring 30. Bias spring 3
A connecting portion 30d bent in a substantially U shape is formed at one end of 0, and a cutout groove 30e is formed in the connecting portion 30d. On the other hand, the frame 33 has a connecting piece 33i protruding in the thickness direction.
Is provided, and the adjusting knob 34e is screwed into the connecting piece 33i. The connecting portion 30d of the bias spring 30 is wound around the adjusting knob 34e, and an engaging protrusion 34f provided on the peripheral surface of the adjusting knob 34e is engaged with the cutout groove 30e. Therefore, when the adjusting knob 34e is rotated, the tip end portion of the bias spring 30 is moved to the first reversing plate 3.
It is possible to adjust the force of pressing the first reversing plate 3
It is possible to adjust the spring force acting from the bias spring 30 with respect to 4. That is, the adjusting knob 34e functions as bias adjusting means. Adjustment knob 34
The end face of e faces the opening face side of the body 11, and a minus groove 34g is formed in this end face so that it can be operated by a minus driver or the like. Therefore, the cover 1
By removing 2, the spring force of the bias spring 30 can be adjusted. Connect the adjusting knob 34e to the connecting piece 33i.
Instead of being screwed and attached, the connection piece 33i may be press-fitted. Other configurations are similar to those of the first embodiment.

[0040]

As described above, the present invention is provided with the bias adjusting means for applying the restoring force to the first reversing plate by the bias spring and adjusting the restoring force by the bias spring. You can adjust the movements of the parts. Therefore, the variation of the spring force of the reversing spring and the like can be absorbed only by the reversing mechanism section, and it is not necessary to prepare a plurality of types of parts having different specifications. In other words, when the reversing mechanism is automatically returned when the thermal element is returned, the bias spring and the bias adjusting means can absorb variations in the operation of the reversing mechanism.

[Brief description of drawings]

1A and 1B show an inversion mechanism used in Example 1, where FIG. 1A is an exploded perspective view and FIG. 1B is a partially cutaway side view.

FIG. 2 is an operation explanatory view of the reversing mechanism portion of the embodiment.

FIG. 3 is an exploded perspective view of the embodiment.

FIG. 4 is an external perspective view of the embodiment.

FIG. 5 is an exploded perspective view of the embodiment.

FIG. 6 is a rear view of the embodiment with the cover and the inner lid removed.

FIG. 7 is a vertical sectional view of an example.

FIG. 8 is a front view of the embodiment.

FIG. 9 is a vertical sectional view of an example.

FIG. 10 is an exploded perspective view of an operating point adjusting mechanism portion used in the embodiment.

FIG. 11 is an exploded perspective view of a main part showing an embodiment.

FIG. 12 is a diagram showing an assembling process of a main part according to the embodiment.

FIG. 13 is an operation explanatory diagram of the main parts of the embodiment.

FIG. 14 is an operation explanatory diagram of the main parts of the embodiment.

FIG. 15 is a transverse cross-sectional view of a main part of the example.

FIG. 16 is a plan view of a main part of the embodiment.

FIG. 17 is a rear view showing a state in which a cover and an inner lid of a main part of the embodiment are removed.

FIG. 18 is a rear view of the embodiment with the cover removed.

FIG. 19 is a perspective view of an inner lid used in the embodiment.

FIG. 20 is a cross-sectional view of a main part of the example.

FIG. 21 is an exploded perspective view of a reversing mechanism used in Example 2.

FIG. 22 shows an inversion mechanism used in Example 3, (a)
Is an exploded perspective view, and (b) is a side view of a main part.

FIG. 23 shows an inversion mechanism used in Example 4, (a)
Is an exploded perspective view, and (b) is a side view of a main part.

FIG. 24 shows an inversion mechanism used in Example 5, (a)
Is an exploded perspective view, and (b) is a side view of a main part.

FIG. 25 is an operation explanatory view of a conventional reversing mechanism section.

FIG. 26 is an exploded perspective view of a conventional reversing mechanism section.

FIG. 27 is a schematic configuration diagram of a conventional reversing mechanism section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body 2 Thermal element 4 Contact device 30 Bias spring 31 Inversion mechanism part 33 Frame 33f Spring support hole 34 First inversion plate 35 Second inversion plate 36 Inversion spring 38 Operation plate

Claims (1)

[Claims] 1. A thermal element that displaces in accordance with the amount of energization, and a first reversing plate and a second reversing plate that are respectively swingably held with respect to a frame fixed at a fixed position of a body. A reversing mechanism section that interlocks via a reversing spring to regulate the swing range of the second reversing plate between two stable positions, and a reversing mechanism of the thermal element when the second reversing plate is located at one stable position. An actuating plate for exerting a pressing force on the first reversing plate according to the displacement, and a second
In the thermal relay having a contact device that opens and closes in accordance with the swing of the reversing plate, the reversing mechanism portion causes the first reversing plate to heat when the second reversing plate is positioned at one stable position. The center line of the reversing spring is moved around the point of action of the spring force on the second reversing plate by receiving the pressing force from the actuating plate due to the displacement of the moving element, and the fulcrum of the second reversing plate and the second The second reversing plate is configured to move rapidly to the other stable position when the straight line connecting the point of application of the spring force to the reversing plate is moved to the other stable position. A thermal relay comprising: a bias spring that applies a restoring force to the first reversal plate in a direction to position the bias plate; and a bias adjusting unit that adjusts the restoring force of the bias spring.