JP2000188052A - Adjusting spring structure of thermal overload relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify structure and facilitate assembly by installing a plate spring, a spring locking recess, a sloped protrusion, and a cover, and deforming the plate spring with the sloped protrusion to pressingly support an operation rod. SOLUTION: Before mounting an adjusting spring structure 50 on a frame body 11, an operation rod 31 is arranged in an operation rod housing space 51 of an opening on one side so that the end on the side where a reverse lever of the operation lever 31 is installed is engaged with a current adjusting mechanism. In this step, the plate spring 52 comes in slight contact with the operation rod 31. Next, a cover 56 is faced to a frame 11 so that the sloped protrusion 55 installed in a cover 56 can be inserted into a gap between the plate spring 52 and an end wall 57 of an operation rod housing space 51. Then, by mounting the cover 56 on the frame 11, the other end of the plate spring 52 slides along the inclined surface of the sloped protrusion 55, the plate spring 52 deforms to pressingly support the operation rod 31, and the operation rod 31 is elastically supported with the current adjusting mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adjusting spring structure of a thermal overload relay having a simple structure and easy to assemble.

[0002]

2. Description of the Related Art In general, a thermal overload relay is configured by arranging a heater and a contact opening / closing mechanism in a vertical relationship, and arranging an actuating device beside the heater. Adjusted to each point by the adjustment mechanism, 80-12
It is maintained at the 0% position. An adjusting spring structure is provided so that the operating rod of the operating device maintained at the position of 80 to 120% does not rattle at that position.

Since the adjusting spring structure is configured to apply a load to the operating rod at the time of assembling, it must be formed into a shape corresponding to a state before assembling. Adjustment spring structure must be prepared.

[0004]

The adjustment spring structure of a thermal overload relay of the above type must be manufactured in various shapes according to the adjustment position of the operating rod of the operating device, so that maintenance and management are troublesome. In addition, there is a problem that the manufacturing cost is high, and since it has to be pushed between the frame body and the operating rod at the time of assembling, time and labor are required for assembling.

The present invention has been made in view of the above points, and has as its object to provide an adjustment spring structure of a thermal overload relay having a simple structure and easy to assemble.

[0006]

According to the present invention, there is provided an adjusting spring structure for a thermal type overload relay, comprising: a leaf spring for pressing an operating rod disposed in an operating rod receiving space provided at one side of an opening provided in a frame; A spring locking recess formed on the other side wall surface of the operating rod accommodating space to support one end of the leaf spring, and a cover having an inclined convex portion for pressing the other end of the leaf spring toward the operating rod and attached to the frame. And an operating rod disposed in the operating rod housing space.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 10 denotes a thermal overload relay, and the thermal overload relay 10 has a frame 11. A heater unit 12 is arranged below the inside of the frame body 11, an actuator 13 is arranged beside the heater unit 12, and a contact opening / closing mechanism 14 is arranged above the heater unit 12.

The heater section 12 has a heating element 17 formed by winding a heater wire 16 around a bimetal 15.
Having. In the three-phase main circuit shown in FIG. 1, three heat elements 17 are arranged in parallel in the vertical direction (only one is shown for simplicity of the drawing). Each heat element 17 has a lower end of the bimetal 15 engaged with a movable plate 18 or a differential plate 19.

As shown in FIG. 1, the contact opening / closing mechanism 14 includes a fixed contact 21 fixed to the frame 11, a movable contact 22 arranged to be able to contact and separate from the fixed contact 21, and a movable contact 22. Is provided at the lower end, and a slider 24 that is arranged movably in the horizontal direction and swings the movable contact 23.

The operating device 13 has a reversing mechanism 20, and an operating rod 31 of the reversing mechanism 20 is rotatably supported at an intermediate portion on a side wall of the frame 11. Operating rod 3
One end of the temperature compensating bimetal 32 is engaged with 1.
The other end of the temperature compensating bimetal 32 is in contact with the tip of a differential lever (not shown) engaged with the movable plate 18 or the differential plate 19. A reversing lever 33 is provided integrally with the end of the operating rod opposite to the temperature compensating bimetal 32.
The end on the reversing lever 33 side is engaged with the current adjusting mechanism 40.

As shown in FIG. 1, the current adjusting mechanism 40 includes a current adjusting knob 42 rotatably provided in a concave portion 41 provided on an end face of the frame 11, and a current adjusting knob 42.
Screw means 43 provided on the small diameter portion of
3 and a cam body 44 connected to the current adjusting knob via the control knob 3. The cam body 44 has a substantially cylindrical shape in its entirety, includes a spirally extending cam surface, and is concentrically connected to the current adjusting knob 42. The operating rod 3 is placed on the spiral cam surface of the cam body 44.
One end is engaged. The cam surface of the cam body 44 has an inclination angle that rises to the right and moves about 1.7 mm in the axial direction in one rotation.

The operating rod 31 is adjusted to each point by the current adjusting mechanism 40. In order to prevent the operating rod 31 from rattling at the adjustment position, the adjusting spring structure 50 presses the operating rod 31. Built to be.

As shown in FIG. 2, the adjusting spring structure 50 includes a leaf spring 52 which presses the operating rod 31 disposed in the operating rod receiving space 51 having one side opening provided in the frame body 11, and the operating rod A leaf spring 52 formed on the other side wall surface 53 of the accommodation space 51
And a cover 56 attached to the frame 11. The cover 56 has an inclined protrusion 55 for pressing the other end of the leaf spring 52 in the direction of the operating rod 31.
Are formed. The tip 55a of the inclined convex portion 55 is set to a size that can be inserted into the gap between the leaf spring 52 and the end wall 57 of the operating rod housing space 51.

Next, the operation will be described.

Before the adjusting spring structure 50 is incorporated into the frame 11, the operating rod 31 is first moved so that the end of the operating rod 31 on the side where the reversing lever 33 is provided is engaged with the current adjusting mechanism 40. It is arranged in the operating rod housing space 51 with one side opening.

Next, as shown in FIG. 2A, the leaf spring 52 is arranged so that one end thereof is locked in the spring locking recess 54. At this stage, the leaf spring 52 is in a state of lightly touching the operating rod 31.

Next, the inclined convex portion 55 provided on the cover 56
The cover 56 is arranged to face the frame 11 so that the cover 56 can be inserted into the gap between the leaf spring 52 and the end wall 57 of the operating rod housing space 51. Following this, as shown in FIG.
6 is attached to the frame 11. By attaching the cover 56 to the frame body 11, the other end of the leaf spring 52 slides along the inclined surface of the inclined projection 55, the leaf spring 52 is deformed, and the deformed leaf spring 52 is Operating rod 31 arranged at
Is pressed and supported. As a result, the operating rod 31 is elastically supported by the current adjusting mechanism 40.

FIG. 3 shows another embodiment of the present invention. In the embodiment shown in FIG. 3, as shown in FIG. 4, a leaf spring 60 has a substantially U-shaped support portion at one end. 61. The height L of the support portion 61 is set to such a size that the leaf spring 60 is deformed similarly to the leaf spring 52 shown in FIG. In the embodiment shown in FIG. 3, it is not necessary to provide the inclined projection 55 on the cover 56.

[0019]

As described above, according to the present invention, the leaf spring for pressing the operating rod is provided in the direction of the operating rod by the spring engaging concave portion for supporting one end of the leaf spring and the inclined convex portion provided on the cover. By pressing, the operating rod can be held at the position adjusted by the current adjusting mechanism due to the deformation of the leaf spring, and
It has a simple structure and can be easily assembled.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a thermal overload relay incorporating an adjustment spring structure according to the present invention.

FIG. 2 is a view showing an adjustment spring structure according to the present invention.

FIG. 3 is a diagram showing another embodiment of the adjustment spring structure according to the present invention.

FIG. 4 is a view showing a leaf spring used in the adjustment spring structure of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Thermal-type overload relay 11 Frame 13 Actuator 31 Operating rod 40 Current adjusting mechanism 50 Adjusting spring structure 51 Operating rod accommodating space 52 Leaf spring 54 Spring locking concave part 55 Inclined convex part 56 Cover

Claims (2)

[Claims] 1. A leaf spring for pressing an operating rod disposed in an operating rod housing space of one side opening provided in a frame, and one end of the leaf spring formed on the other side wall surface of the operating rod housing space. By having a spring retaining concave portion and a cover having an inclined convex portion for pressing the other end of the leaf spring in the direction of the operating rod and attached to the frame, the leaf spring is deformed by the inclined convex portion provided on the cover. An adjusting spring structure for a thermal overload relay, wherein the operating rod is pressed and supported. 2. A spring engaging recess formed on the other side wall of the operating rod accommodating space of one side opening provided in the frame, and one end is formed in a substantially U-shape and the other end is formed in the spring engaging recess. An adjusting spring structure for a thermal overload relay, comprising: a leaf spring that is locked; and an operating rod disposed in the operating rod housing space is pressed and supported by the leaf spring.