JPS642404Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) This invention can be used as a resistance value adjusting device for adjusting the resistance value of a variable resistor used for setting the temperature of a heat insulator, for example.

(Background of the idea) For example, in a device that uses a heater to maintain a constant temperature inside, such as a warmer or various experimental equipment, the amount of electricity supplied to the heater is adjusted, and the amount of heat generated by the heater is controlled. A variable resistor is used to keep the temperature constant. Traditionally, sliding type or rotating type variable resistors have been used, but conventional variable resistors can inadvertently change their set value if a part of the body touches them. There was a risk that the temperature inside the device would deviate from the desired value. Also, when converting the set value, in order to know the set value after conversion, it is necessary to switch a switch separate from the variable resistor adjustment dial so that the set value is displayed on the display. The adjustment work was troublesome.

(Purpose of the present invention) The present invention solves the above-mentioned inconveniences, and provides a resistance value adjusting device that prevents the set value from changing inadvertently and that allows the user to know the set value after conversion when converting the set value. is intended to provide.

(Structure of the present invention) In the resistance value adjusting device of the present invention, an annular friction material is attached to the peripheral edge of the side surface facing the resistor body of a disc fixed to the end of the rotating shaft of a rotary adjustable variable resistor. A knob for rotating or pulling the adjusting shaft is fixed to one end of the adjusting shaft which is provided to be rotatable and movable in the longitudinal direction parallel to the rotating shaft, and a knob for rotating or pulling the adjusting shaft is fixed to the other end. A piece having a conical surface that can be brought into contact is fixed, and an elastic force is applied to this adjustment shaft in the direction of separating the conical surface and the annular friction material. It is constructed by providing a changeover switch that moves only when the conical surface and the annular friction material come into contact with each other.

(Operation of the present invention) Since the resistance value adjusting device of the present invention is constructed as described above, normally the conical surface of the bridge piece and the annular friction material are in a state of being separated, and the knob may be inadvertently rotated. Even if the variable resistor is turned, the rotating shaft of the variable resistor will not rotate, and the set resistance value will not change inadvertently. To change the setting value, rotate the knob while pulling it against the elastic force, and the rotation of the adjustment shaft will be transmitted to the rotary shaft of the variable resistor via the piece, the annular friction material, and the disc. The resistance value of the variable resistor can be changed. At the same time, the changeover switch switches the circuits of the various controllers so as to indicate the above-mentioned resistance value, and the set value based on the converted resistance value is displayed on the display board.

(Embodiments of the present invention) Next, the present invention will be explained in more detail while explaining the illustrated embodiments.

Fig. 1 is a plan view showing an embodiment in which a temperature/humidity regulator is constructed by combining two resistance value regulating devices of the present invention, and Fig. 3 shows the operation of the regulating device incorporated in the temperature regulator. 1 is a schematic diagram illustrating a circuit for. Since the resistance value adjustment device for the temperature controller and the resistance value adjustment device for the humidity controller have exactly the same configuration,
The resistance value adjusting device for the temperature controller shown in the left half of FIG. 1 will be explained below.

Standing walls 1b, 1c are provided at both front and rear edges of the substrate portion 1a.
Frame 1 formed by folding at right angles in the same direction
A rotationally adjustable variable resistor 2 is fixed to the rear standing wall 1c (upper side in FIG. 1) with a rotating shaft 3 for adjusting the resistance value protruding from the front of the standing wall 1c. A disk 4 is fixed to the front end of the rotating shaft 3 of the variable resistor 2, and an O-ring 5 is attached to the peripheral edge of the rear side of the disk 4 as an annular friction material.

Further, an adjustment shaft 6 is provided passing through the ends of the vertical walls 1b, 1c of the frame 1 and parallel to the rotation shaft 3. This adjustment shaft 6 is attached to the vertical walls 1b and 1c so that it can freely slide in the longitudinal direction and rotate in the torsional direction. A piece 7 and a flange piece 8 are fixed to each other in order from the side of 1c with a slight interval between them. The front end of the piece 7 fixed to the rear has a conical surface 7a whose diameter gradually becomes smaller toward the front.
The distance between the adjustment shaft 6 and the rotating shaft 3 is determined such that the conical surface 7a and the O-ring 5 come into contact when the adjustment shaft 6 is pulled forward.

On the other hand, on the front side of the collar piece 8 fixed to the adjustment shaft 6 approximately in the middle of the vertical walls 1b, 1c, the other end of the swing plate 10 is attached to the changeover switch 9 fixed to the frame 1. are in contact. A portion of the front side surface of this swing plate 10 is in contact with a push button 11 for switching the contact point of the changeover switch. This push button 1
1 is given elasticity by a spring built into the changeover switch 9 so that it always tends to protrude upward in FIG. The adjustment shaft 6 is pressed by the tip of the plate 10 via the collar piece 8.
As long as no other external force is applied, the piece 7 moves backward until it comes into contact with the vertical wall 1c, as shown in FIG. 1, and the conical surface 7a and the O-ring 5 are separated from each other. The front end of the adjustment shaft 6 is connected to the operation panel 12.
It protrudes forward, and a dial-type knob 13 is fixed to the front end thereof.

Next, the operation of the resistance value adjusting device configured as described above will be explained with reference to FIG. 2.

First, when not adjusting the resistance, as shown in FIG.
Even if the adjustment shaft 6 is inadvertently rotated due to a part of the body touching the knob 13, the rotation shaft 3 of the variable resistor 2 will not rotate and the set resistance value will change. Never. In this case, since the push button 11 of the changeover switch 9 is not pressed by the rocking plate 10, the contacts of the changeover switch 9 are made conductive as shown by the solid line in FIG. A signal from the heat sensitive element 14 is sent to a temperature display 15, which indicates the temperature inside the heat insulator. The temperature inside the heat insulator is determined by comparing the resistance value of the heat sensitive element 14 and the resistance value of the variable resistor 2 using the temperature controller 16. When the temperature is lower than the set temperature substituted with the value, the desired set temperature is maintained by energizing the heater (not shown) for warming the inside of the chamber.

When adjusting the resistance value of the variable resistor 2 to change the set temperature, pull the knob 13 and press the piece 7.
The knob 13 is rotated with the conical surface 7a of the O-ring 5 in contact with the O-ring 5. The rotational force applied to this knob 13 is transmitted to the rotating shaft 3 of the variable resistor 2 via the adjusting shaft 6, piece 7, O-ring 5, and disc 4, and rotates this rotating shaft 3 to Convert the resistance value of resistor 2. At this time, the tip of the rocking plate 10 is pushed by the collar piece 8 fixed to the adjustment shaft 6, and the push button whose tip is in contact with the side surface of the rocking plate 10 is pressed, and the changeover switch 9 is switched to the second position. It is switched to the state shown by the chain line in the figure. Therefore, a signal obtained by the resistance value of the variable resistor 2 is sent to the temperature indicator 15, which indicates the set temperature adjusted by adjusting the resistance of the variable resistor 2.
Therefore, the set temperature can be easily converted while viewing the display on the temperature display 15.

In addition, in the illustrated embodiment, the piece 7 and the O-ring 5
Press button 1 of selector switch 9 to increase the elasticity to release the
1 was obtained by a spring built into the changeover switch 9, but such elasticity can also be obtained by providing a suitable spring between the frame 1 and the adjustment shaft 6. In this case, the push button 11 of the changeover switch 9 is configured to be pressed by a flange piece 8 or other protruding portion fixed in the middle of the adjustment shaft 6.

(Effects of the present invention) Since the resistance value adjusting device of the present invention is configured and operates as described above, the set resistance value will not change inadvertently, and when incorporated into various regulators, Adjustment work can be performed easily and reliably because adjustment work can be performed while viewing the set values that are automatically displayed.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the resistance value adjusting device of the present invention, and FIG. 2 is a circuit diagram showing a state in which this device is incorporated into a temperature controller. 1... Frame, 1a... Board part, 1b, 1c
... Standing wall, 2 ... Variable resistor, 3 ... Rotating shaft, 4
... Disk, 5 ... O-ring (annular twisted material), 6
...Adjustment shaft, 7... Piece, 7a... Conical surface, 8...
...Flame piece, 9...Selector switch, 10...Swing plate,
11...Push button, 12...Operation panel, 13...Knob, 14...Thermosensitive element, 15...Temperature display, 1
6...Temperature controller.

Claims (1)

[Scope of utility model registration request] An annular friction material is attached to the periphery of the side surface facing the resistor body, which is a disc fixed to the end of the rotating shaft of a rotary adjustable variable resistor, and can freely rotate and move in the length direction in parallel to the rotating shaft. A knob is fixed to one end of an adjustment shaft provided on the shaft, and a piece having a conical surface that can come into contact with the annular friction material is fixed to the other end, and the conical surface and the annular friction material are connected to the adjustment shaft. A changeover switch is provided near the adjustment shaft to provide elasticity in the direction of separation, and to switch only when the adjustment shaft moves against the elasticity and the conical surface and the annular friction material come into contact. Resistance value adjusting device consisting of: