JPH0128607Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a temperature setting device for a thermostat, and its purpose is to
By varying the tension of a spring for adjusting the set temperature against a pressure-responsive member such as a bellows, by using a relatively long contact stroke between a linearly moving adjustment slider and a cam plate that engages with it,
The advantages are that it eliminates the hardness during manual operation, provides smooth operation, and facilitates fine adjustment.

An embodiment of the present invention will be described below with reference to the drawings. In the drawings, reference numeral 1 denotes a temperature-sensitive cylinder filled with a sound-sensing gas, which is connected to the base of a bellows 2 as a pressure-responsive member via a capillary reach tube 1a. The free end portion of the bellows 2 is provided on a horizontal portion 5a of an actuating plate 5 having an L-shaped side surface, which is rotatably supported by a fulcrum 4 with respect to a hole bored in both side walls 3a of the container frame 3. It is in contact with the pivot 6. The vertical portion 5b of the actuating plate 5 supports one end of an actuating rod 7 in the center, and the other end of the actuating rod 7 is provided with a well-known reversing spring 8.
It is connected to a switch operation panel 9 having a switch operation panel 9. A movable contact 10 is provided at the free end of the contact plate 13 that is driven from the switch operation plate 9 via a reversing spring 8, and a fixed contact 11 and a supporting portion 12 opposite thereto are provided.
It is provided so that it can be reversed between.

One end of a main spring 14 that opposes the pressure of the bellows 2 is secured to the upper part of the vertical portion 5b of the L-shaped actuating plate 5, and the other end of the main spring 14 is connected to the nut 1.
5, and the adjusting screw 16 penetrates a hole provided in the front wall 3b of the container frame 3 and projects to the outside.

The head 16a at the other end of the adjusting screw 16 is engaged with a connecting piece 19 that hangs down orthogonally from a swing plate 18 provided at the lower part of the top plate 3c of the container frame 3. The swing plate 18 is rotatably pivoted to the top plate 3c by a fulcrum pin 17.

A slider support plate 20 is provided on the top of the top plate 3c with a gap in parallel thereto, and a straight swing groove 21 is provided in the slider support plate 20 in a direction parallel to the adjustment screw 16. There is.

A cam plate 2 is provided between the top plate 3c and the slider support plate 20.
2 is rotatably supported at its base by the fulcrum pin 17, and the cam surface 23 of the cam plate 22, which has a slight arc shape, intersects the swing groove 21 at an extremely small angle. The circular protrusion 2 of the adjustment slider 24 that is disposed in and slides in the swing groove 21
5 and when the protrusion 25 moves away from the release position near the fulcrum pin 17, the cam plate 22 is rotated about the fulcrum pin 17, thereby causing the connecting piece 19 to move away from the fulcrum pin 17. The spring 14 is driven in the direction of tension.

In the relatively long cam plate 22, the long cam surface extending smoothly toward the free end is vertically stepped, and the circular protrusion 25 engages with the lower cam surface 23, forming a rectangular slider body. The portion 24a engages with the upper cam surface 23a.

A compression spring 26 is arranged between the connecting piece 19 and the front wall 3c of the container frame as a counter torque spring, and is wrapped around the adjusting screw 16 to reduce the difference in load during the reciprocating motion of the adjusting slider.

In the above configuration, when the thermosensor tube 1 senses a temperature rise, the bellows 2 expands, and its free end pushes up the horizontal portion 5a to move the L-shaped actuating plate 5 clockwise against the main spring 14. Rotate. Therefore, the operating plate 5 drives the switch operating plate 9 via the operating rod 7, and the movable contact 10 via the reversing spring 8.
is brought into the state shown in FIG. 2, and the contact between the movable contact 10 and the fixed contact 11 closes, for example, an operating circuit of a refrigerator.

When the temperature decreases, the bellows 2 contracts, and the movable contact 1 closes beyond the dead center of the reversing spring 8 in the opposite direction.
0 separates from the fixed contact 11.

The main part of the present invention is a mechanism for varying the tension of the main spring 14 to change the set temperature. , the cam plate 22 is moved counterclockwise in FIG. 1, and the connecting piece 19 of the rocking plate 18 is moved to the left in FIG. 2, thereby increasing the tension of the main spring 14.

As the adjustment slider 24 approaches the right end of the sliding groove 21, the tension of the main spring 14 increases accordingly;
Since the point of contact with 2 is farther away than the fulcrum pin 1,
The force F on the adjusting slide 24 opposing the tension F ₁ of the main spring 14 is relatively small. The relationship is expressed by the following equation.

F=l ₁ /l ₀ ×F ₁ However, l ₁ is the distance between the fulcrum pin 17 and the axis of the adjustment screw 6, and l ₀ is the distance from the fulcrum pin 17 to the adjustment slider 24 and the cam surfaces 23, 23 of the cam plate 22.
This is the distance to the contact point of a. Moreover, the sliding groove 2
1 and the cam surfaces 23 and 23a intersect at an extremely small acute angle, the amount of rotation of the cam plate 22 relative to the amount of movement of the adjustment slider 24 is small.

Furthermore, since a compression spring 26 is disposed around the adjustment screw 16 between the connecting piece 19 and the opposite machine frame front wall 3b, the adjustment slider 24
The difference in load when reciprocating can be reduced.

A protrusion 27 is provided on the upper surface of the slider support plate 20 at the end of the slider sliding surface near the fulcrum pin 17 in the direction of movement of the slider. I'm trying to get a feel for it.

As described above, the present invention rotatably supports the operating plate for opening and closing the switch relative to the container frame and the long temperature setting cam plate extending toward the free end, and attaches the temperature-sensitive tube to the temperature-sensitive cylinder. One side of the actuating plate is brought into contact with the connected pressure responsive member, and a temperature setting spring is provided between the other side of the actuating plate and the base of the temperature setting cam plate, and between the base of the cam plate and the container frame. A counter-torque spring opposing the temperature setting spring is provided at the cam plate, and an adjustment slider that moves in a substantially linear direction is engaged with the smooth cam surface extending to the free end of the cam plate. The engagement force between the adjusting slider and the cam plate that moves in the direction can be made relatively small, and the temperature can be set smoothly with the adjusting slider, and fine adjustment is easy, and the adjusting slider can be moved to the set position. It has the advantage of being able to be stably positioned, without causing any deviation in the set temperature, and furthermore being able to reduce the load difference when reciprocating the adjustment slider due to the reverse torque spring.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the present invention;
FIG. 2 is a longitudinal sectional view of the same as above, and FIG. 3 is an exploded perspective view. 2... Pressure responsive member, 5... Actuation plate, 14...
Temperature setting spring, 22...Cam plate, 24...
...adjustment slider.

Claims (1)

[Scope of utility model registration request] An actuating plate that opens and closes the switch relative to the container frame and a long temperature setting cam plate that extends toward the free end are rotatably supported, and the actuating plate is attached to a pressure-responsive member connected to the temperature-sensitive cylinder. A temperature setting spring is provided between the other side of the actuating plate and the base of the temperature setting cam plate, and a temperature setting spring is provided between the base of the cam plate and the container frame. 1. A device for adjusting a set temperature of a thermostat, comprising a counter-torque spring and an adjusting slider that moves substantially linearly with a smooth cam surface extending from a free end of a cam plate.