JPS5917072Y2 - thermal relay - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a thermal relay.

Conventionally, in this type of thermal relay, as shown in FIG. 4, first to third bimetals 5', 6',
When 7' was simultaneously overheated and bent, the following behavior occurred.

That is, the first card piece 26 is driven in the A' direction, thereby pressing the protrusion 36 of the differential lever 34'.

The differential lever 34' is rotated in the direction B' about the shaft 35', and the driving protrusion 37' engages the operating lever 39' of the switch section.
Press and drive.

However, since the second card piece 30' is not pressed against the first to third bimetals 5', 6', and 7', the driving protrusion 3 is moved by the reaction force of the operating lever 39.
When 7' is pressed in the C' direction, the shaft 35' is rotated in the D' direction about the protrusion 36'.

Therefore, it was not possible to accurately drive the operating lever 39' by the driving protrusion 37'.

Further, as the shaft 35' rotates in the D' direction, the second
The card piece 30' is rotated in the E' direction and comes into contact with the inner wall of the casing 3', which further increases operational errors.

The present invention seeks to provide a thermal relay that eliminates the above-mentioned drawbacks.

Hereinafter, the thermal relay of the present invention will be explained with reference to the drawings.

1 to 3, ] is an overcurrent detection section, and 2 is a switch section, which are housed separately on the right and left sides of the casing 3, respectively, and the switch section 2 is located at the lower end of the casing 3. The overcurrent detection section 1 is not responsive to the operation of the overcurrent detection section 1 through the connection drive section 4 disposed in the overcurrent detection section 1 .

5, 6. Reference numerals 7 denote first to third bimetals arranged in the overcurrent detection section 1, each corresponding to three phases, each having a low expansion side 5a, 5a, 7a and a high expansion side 5b, 6b, 7b. ing.

8. 9.10 are the first to third bimetals 5.9 through insulating paper 11.12.13 respectively. 6. The first to third bimetal heaters are wound around the outer conductor 14, 18.22, respectively, and one end is connected to the external conductor connection terminal 15, 19, 23 via the connection conductor 14, 18.22, and the other end is connected to the lead piece 16, 20, . 24
is connected to the load side terminals 17.21.25 via.

Reference numeral 26 denotes a first card piece of the connection drive section 4, which is connected to the first to third bimetal parts 5. 6. 7 low expansion side 5a
, 5a, 7a are provided with protrusions 27, 28, 29, respectively.

30 is a second card piece of the connection drive section 4, which is connected to the first to third bimetals 5. 6. 7 high expansion side 5b
, 6b, and 7b are provided with projecting pieces 31, 32, and 33 that are arranged at a slight interval so as to be able to come into contact with each other.

34 is pivotally connected to the second card piece 30 by a shaft 35,
and a differential lever whose protrusion 36 is brought into contact with the first card piece 26, and the first to third bimetal 5
With the exception of at least one card 6.7, when the first card piece 26 is overheated and bent, the first card piece 26 is moved in the direction A, and the second card piece 30 is held at approximately the previous position. , rotates in the B direction about the shaft 35, and presses and drives the subsequent switch section 2 with the first drive protrusion 37, while the first to third bimetal 5. 6. 7 are all overheated and bent, the first card piece 26 is moved in the direction A, and the second card piece 30 is
to third bimetal 5. 6. 7, the switch portion 2 is moved between the first and second drive protrusions 37.
Pressing drive is performed at 38.

Reference numeral 39 denotes an operation lever of the switch section 2 which is pressed and driven by the drive protrusions 37 and 38 of the connection drive section 4. As shown in FIG. The contact spring 42 is brought into contact with a reversing spring support portion 43 that is provided to be swingable from side to side.

44 is a movable contact fixed to the upper part of the movable contact spring 42, and a normally closed contact 46 is fixed to the extension of the normally closed terminal 45.
It is brought into contact with the

A common terminal 47 is connected to the movable contact spring 42 as appropriate.

Reference numeral 48 denotes a reversing spring, one end of which is locked to the main body 42a of the movable contact spring 42, and the other end is locked to the reversing spring support portion 43.

49 is a normally open terminal, which is connected to the contact support 5 via a support spring 50.
1 is held, and a normally open contact 52 that can make contact with the movable contact 44 is fixed to the contact support 51.

Reference numeral 53 designates a return button having a protrusion 54 that presses the contact support 51 against the support spring 50 when pressed down, and a notch 56 into which the switching lever 55 can slide and engage is formed. , can be appropriately held in the depressed state when depressed.

Reference numeral 57 denotes an operating knob portion of the switching lever 55, which protrudes from the sliding hole 58 of the casing 3 and is connected to the return button 53.
By pressing down and sliding in the C// direction, the hemispherical protrusion protruding from the tip 59 bent downward into an L-shape will fit into the recess 60 of the notch 56, and the return button will be pressed. 53 in the depressed state and return.

Reference numeral 61 denotes a dial interlocking lever, the base end of which is pivotally supported by a rotating shaft 62, and the center part of which is connected to the support piece 41 via an adjustment screw 63.
In addition, the upper end portion is pressed against the eccentric operating portion 65 by a support spring 64.

Reference numeral 66 denotes an adjustment dial disposed on the upper surface of the casing 3 and integrated with the eccentric operation section 65. By appropriately rotating the adjustment dial 66, the dial interlocking lever 61 is displaced, and the support piece 41 is adjusted in accordance with the current capacity. It is designed to allow for fine-tuning.

Reference numeral 67 denotes a test card piece that, when the return button 53 is pushed down further than the operating position of the contact support 51, detects the overcurrent detection unit 1.
By moving the reversing spring support portion 43 of the movable contact spring 42 in the same direction, the reversing spring 48 is reversed, and the movable contact 44 can be closed to the normally open contact 52 again.

Furthermore, the operation of the thermal relay of the present invention will be explained in detail.

Now, the first to third bimetal heaters 8°9.10
If an overcurrent flows through all of the first to third bimetal 5. 6. 7 is heated and bent, and the tip thereof is moved in a direction approaching the switch section 2.

As the first to third bimetals 5°6.7 are overheated and bent, the first card piece 26 is moved in the direction A, and the protrusion 36 of the differential lever 34 is pressed.

At this time, the protrusions 31, 32, 33 of the second card piece 30
5. The first to third bimetals. 6. The differential lever 3 is slightly spaced apart from the tip of the differential lever 3.
4 is not rotated in the direction B about the shaft 35, therefore, both of the driving protrusions 37 and 38 of the differential lever 34 push and drive the operating lever 39 of the subsequent switch section 2.

That is, the first to third bimetals 5. 6. 7 are all heated and bent, the differential lever 34 is in different positions.
Since the driving protrusions 37 and 38 push and drive the operating lever 39 of the subsequent switch section 2, the differential lever 39 will not be rotated due to the reaction force from the operating lever 39, and the differential lever 39 will be able to operate extremely accurately. The operating lever 39 can be driven.

In addition, since the differential lever 34 is not rotated, the second card piece 30 connected by the shaft 35 is also not rotated.

Therefore, errors caused by the frictional force that the second card piece 30 receives from the inner wall of the casing 3 can be eliminated.

In addition, the first to third bimetal heaters 8°9.1
0, for example, the first bimetal heater 8, the first bimetal 5 is overheated and bent, and its tip is moved in the direction approaching the switch section 2.

On the other hand, the second and third bimetals 6.7 are not bent due to overheating and remain in their original positions.

Therefore, the first card piece 26 is moved in the A direction and presses the protrusion 36 of the differential lever 34, but the second card piece 30 is moved in the A direction by the second and third bimetals 6.7. Since the differential lever 34 is prevented from moving, the differential lever 34 is rotated about the shaft 35 in the direction B.

As a result, only the first driving protrusion 37 of the differential lever 34 presses and drives the operating lever 39 of the subsequent switch section 2.

At this time, due to the reaction force from the operating lever 39, the differential lever 34 cannot be rotated in the C direction about the shaft 35, but as described above, the second card piece 30 2. Since it is held still by the third bimetal 6.7, rotation of the differential lever 34 in the C direction due to the reaction force is prevented.

In addition, in the thermal relay of the present invention, the line of action between the bimetal and the first card piece 26 is made to coincide with the line of action between the first card piece 26 and the protrusion 36 of the differential lever 34. As a result, the first card piece 26 is moved only in the direction of the line of action.

Therefore, operational accuracy can be improved. As is clear from the above, the thermal relay of the present invention has a first card piece 2.
The bimetallic parts 5.6 and 31.32.33 of the second card part 30 are interposed between the protruding pieces 27, 28, and 29 of the second card part 30, respectively. 6.
7 is secured, and in addition, two driving protrusions 37 and 38 are formed on the differential lever 34 to press and drive the operating lever 39 of the subsequent switch section 2 at two points. Therefore, (A) Bimetal5. 6. 7 are all overheated and bent, the drive protrusion is not rotated in the reverse direction by the reaction force from the operation lever 39, and setting errors, variations in operation, and slow operation can be eliminated. Since the first card piece 26 is moved in a straight line, significant practical effects such as (B) improved operational accuracy and (C) improved reliability are achieved.

[Brief explanation of the drawing]

Fig. 1 is an internal front view of an embodiment of the thermal relay of the present invention, Fig. 2 is a partial sectional view taken along line II-II' in Fig. 1, Fig. 3 is a perspective view of the same part, and Fig. 4 shows a conventional example. 1...Overcurrent detection section, 2...Switch section, 3...Casing, 4...Connection drive section, 5. 6. 7...Bimetal, 5a,
5a, 7a...Low expansion side of bimetal, 5b,
6b, 7b... High expansion side of bimetal, 5c, 6c, 7c... Recess, 8.9, 10.
...Bimetal heater, 11.12.13.
...Insulating paper, 14, 18.22 ... Connection conductor, 15.19.23 ... External conductor connection terminal, 16.20.24 ... Lead piece, 17.21
゜25...Load side terminal, 26...1st
Card piece, 27°28, 29.32.33.34.
... Protruding piece, 30... Second card piece,
34...Differential lever, 35...Shaft, 35
a...Latching hole, 36...Protrusion, 37
．． 38... Drive protrusion, 39... Operation lever, 40... Pin, 41... Support piece, 42... Movable spring, 42 a... Spring body, 43... Reversing spring support part, 44...
...Movable contact, 43...Normally closed terminal, 46...
...Normally closed contact, 47...Common terminal, 48.
...Reversing spring, 49... Normally open terminal, 50
...Support spring, 51...Contact support body,
52... Normally open contact, 53... Return button,
54...Protrusion part, 55...Switching lever, 56...Notch, 57...Operation knob part, 58...Sliding hole , 59...Tip part,
60...Recess, 61...Dial interlocking lever, 62...Rotary shaft, 63...Adjustment screw, 64...Support spring , 65...
Eccentric operation part, 66...Adjustment dial, 67...
...Test card piece.

Claims (1)

[Scope of utility model registration request] In response to overheating curvature of the bimetal disposed in the overcurrent detection section due to overcurrent, a switch adjacent to the overcurrent detection section is connected via a connection drive section disposed at the lower end of the bimetal. In the thermal relay, the connection drive section is driven by a first card piece engaged with a low expansion side of the lower end of the bimetal, and the switch part is driven by the first card piece. and a second card piece that is attached to the high expansion side of the lower end of the bimetal and whose one end is pivotally supported by the differential lever, the first card piece and the second card piece. The first card piece and the second card piece are arranged so that the bimetal can be inserted with a slight gap between them, and two drive protrusions that drive the switch part are arranged. A thermal relay, wherein the differential lever has a protrusion formed on the differential lever, and a protrusion that is driven to be pressed against the first card piece between the two driving protrusions protrudes from the differential lever.