JPH0132269Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an improvement of a thermostat that opens and closes a switch contact through an operating rod that is linked to the movement of a thermally responsive body. This invention relates to a thermostat equipped with a forced opening/closing mechanism.

A deformed U-shaped leaf spring is used as the spring that opposes the movement of the thermally responsive body, and the load of the leaf spring is adjusted using a screw and further cam means, and the movement of the thermally responsive body is transmitted to the switch via the operating rod. , a thermostat in which contacts are opened and closed has already been proposed by the present applicant. However, in this proposed invention, the initial setting of the operating temperature is performed using an adjustment screw, and furthermore, the operating temperature is adjusted by adjusting the position of the cam after it is installed in the equipment used, and the switch can be turned on regardless of the temperature. Since it does not have a mechanism for forcibly opening and closing, it is extremely inconvenient for inspections and the like.

The purpose of the present invention is to improve the operating rod in order to eliminate the above-mentioned drawbacks, and to provide a thermostat having a forced opening/closing mechanism that opens and closes the switch regardless of the temperature in conjunction with the existing cam means. be.

Embodiments of the present invention will be described below based on the drawings.

Figures 1 to 3 show a thermostat that has already been applied for by the applicant. Figure 1 is a configuration diagram showing the internal structure, Figure 2 is a cam means, and Figure 3 is a schematic diagram showing the operation. This is what is shown.

A temperature sensing part is configured and connected to the tip of a capillary tube 3 to the thermally responsive body 1, and a deformed U that comes into contact with the thermally responsive body 1 is connected to the thermally responsive body 1.
The letter-shaped leaf spring 5 has a leaf spring load adjustment screw 6 at the end of the long side 5' and an adjustment operated by a cam 7 at the end of the short side 5 which is continuous via the arcuate bent part 5''. A locking hole 5 in which the shaft 10b engages, a contact point 5a between the plate spring 5 and the thermally responsive body 1, and a load adjustment screw 6 engages.
A fulcrum 4a of the leaf spring 5 is provided in the middle between the leaf spring 5 and the leaf spring 5, and the load of the leaf spring on the thermally responsive body 1 is adjusted by vertical movement of the adjustment shaft 10b by rotation of the adjustment screw 6 and the cam.

As shown in FIG. 2, the cam 7 has a guide plate 9 having a guide groove 9a for guiding the slider 8, a cam groove 10a drilled at an appropriate angle from the center line, and is integrated with the adjustment shaft 10b. The cam plate 10 is rotatably supported on a guide plate 9 by a pivot shaft 11, and the guide plate 9 is attached to a housing 4.
The adjustment shaft 10b passing through the adjustment shaft through hole 4b in the outer wall of the intermediate portion is fixed to the outer wall of the casing when it is engaged in the locking hole 5c of the leaf spring 5.

By moving the slider 8 along the guide groove 9a, the cam plate 10 rotates about the pivot 11,
The adjustment shaft 10b moves in the same direction as the operating direction of the thermally responsive body 1 to adjust the leaf spring load.

Inside and above the housing 4, there is a contact plate 15 having at one end a fixed contact 12, a terminal 13 that connects to the fixed contact and protrudes to the outside of the housing, and a movable contact 14 that connects to the fixed contact, and is connected to the contact plate. A switch consisting of a terminal 16, a snap operating plate 15b formed on a part of the contact plate 15, a reversing spring 17 disposed between the contact plate 15 and the snap operating plate 15b, and an adjusting screw 18 for adjusting the contact gap. A snap actuating plate 15b of the leaf spring 5 and the switch body is provided.
An operating rod 19 is provided between them for transmitting the action of the leaf spring 5 to the switch body.

The initial setting of the operating temperature is done by adjusting the load of the plate spring 5 against the thermally responsive body by moving the adjusting screw 6 forward and backward, and the operating temperature is adjusted after it is installed in the device by moving the slider 8 of the cam. This is done by moving the adjustment shaft 10b up and down by adjusting the position along the guide groove 9a to change the leaf spring load.

The present invention provides a thermostat with the above configuration,
The leaf spring 5 is attached to the operating rod 19 in the normal cam operation range.
It is provided with one or two engaging pawls 20 that do not engage with the end of the plate spring 5, but engage with the end 5d of the leaf spring 5 when operated beyond the normal operating range. FIG. 4 shows a partially enlarged view of the main part of the embodiment of the present invention, in which the end 5d of the leaf spring 5 is attached to the side surface of the actuating rod 19.
This example shows an example in which an engaging claw 20b for forced on is provided above an engaging claw 20a for forced off while holding the cam between the two. Beyond this range, for example, the adjustment shaft 10
If the end portion 5d of the leaf spring is engaged with the engaging claw 20b at b, and the actuating rod 19 is forcibly pushed down, the snap actuating plate 15 of the contact plate 15 is released regardless of the temperature of the thermally responsive body.
b and the action of the reversing spring 17 force the contacts 12 and 14 to turn off. In the above example, the engaging pawl is used for both forced off and forced on, but it can also be used only for forced on, for example.

As described above, the present invention uses a deformed U-shaped leaf spring consisting of a short side and a long side connected through an arc-shaped bent part, and makes the deformed U-shaped leaf spring oppose a pressure-responsive body. engaging an adjusting screw with the free end of the long side, transmitting the movement of the cam means to the short side, and transmitting the movement of the pressure responsive body to the switch via the actuating rod;
At least one engaging pawl that engages with the short side of the leaf spring is provided on the operating rod, and the short side of the leaf spring engages only when the cam is operated beyond the normal cam operation range. By engaging with the engaging pawl and restraining the movement of the operating rod, the switch contact can be opened or closed regardless of the movement of the pressure responsive body.
The deformed U-shaped leaf spring can serve both as an actuating plate for transmitting the motion of the pressure-responsive body and as a spring for setting the temperature against the pressure-responsive body. The short side of the deformed U-shaped leaf spring, which is displaced in accordance with the operation, immediately restrains the operation of the operating rod due to the increase in its displacement, so that the switch contact opens or closes regardless of the movement of the pressure-responsive body. Therefore, the thermostat can be forcibly turned on or off, and the configuration of this type of thermostat can be greatly simplified compared to conventional ones.

[Brief explanation of the drawing]

Figures 1 to 3 show the conventional structure of a thermostat to which the present invention is applied. Figure 1 is the internal structure, Figure 2 is the cam means, Figure 3 is a schematic diagram showing the operation, FIG. 4 is a partially enlarged view showing the main parts of the present invention. 1... Thermal response body, 5... Leaf spring, 6... Leaf spring load adjustment screw, 7... Cam, 8... Slider, 9
...Guide plate, 10...Cam plate, 11...Pivot, 1
2... Fixed contact, 14... Movable contact, 13, 16
... Terminal, 15 ... Contact plate, 19 ... Operating rod, 2
0... Engaging claw.

Claims (1)

[Scope of utility model registration request] A deformed U-shaped leaf spring consisting of a short side and a long side connected together via an arc-shaped bent part is used, and the deformed U-shaped leaf spring is opposed to a pressure-responsive body to form a free end of the long side. transmitting the movement of the cam means to the short side, transmitting the movement of the pressure-responsive body to the switch via the actuating rod, At least one engaging pawl is provided that engages with the operating rod, and only when the cam is operated beyond the normal cam operation range, the short side of the leaf spring engages with the engaging pawl and the actuating rod is rotated. A thermostat characterized in that a switch contact can be opened or closed regardless of the movement of a pressure-responsive body by restricting the movement.