JPH0155530B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermostat that has a simplified mechanism and that allows effective and appropriate setting of the load on the pressure responsive member.

Thermostats conventionally used in refrigerators, room air conditioners, etc. are thermoresponsive thermostats consisting of a bellows or the like that converts the temperature detected by a temperature sensing part into mechanical movement, as shown in Utility Model Publication No. 9569/1983, for example. One side of an actuating plate with an L-shaped side surface and an L-shaped intersection as a fulcrum is brought into contact with the body, one end of a coiled spring is secured to the other side of the actuating plate, and the other end of the spring is attached to an adjusting plate. The adjustment plate is screwed on with an adjustment screw to adjust the spring load, and the adjustment plate is tilted by cam means using one end as a fulcrum to adjust the spring load.The adjusted spring load is opposed by the thermally responsive body, and the thermally responsive The switch contacts are opened and closed via the actuating rod by the rotation of the actuating plate in conjunction with the movement of the body, but the mechanism is complicated due to the large number of parts.

Therefore, a greatly simplified version of this is shown in Japanese Utility Model Application Publication No. 57-43536,
In this case, the actuating plate is omitted and the micro switch is directly driven by the leaf spring member, and there are design bottlenecks in the arrangement of the switch, etc., and the load of the leaf spring against the bellows is effectively controlled. Difficult to configure properly.

The present invention has been made with attention to the above points, and includes an operation in which a thermally responsive body and a switch are provided facing each other, and the movement of the bellows is transmitted between the two in the axial direction to transmit the action of the bellows to the opening/closing action of the switch. By providing a rod, the mechanism is simplified and the movement of the bellows is accurately transmitted to the switch, and a U-shaped leaf spring is used to set a load against the bellows, and the U-shaped leaf spring is used to set the load against the bellows.
The load is effectively and appropriately changed by changing the shape of the arcuate bent portion of the letter spring.

An embodiment of the present invention will be described below with reference to the drawings.

In the drawing, A is a synthetic resin casing;
It consists of a front casing A ₁ and a rear casing A ₂ , which are connected by means described later to constitute a front wall 1, a rear wall 2, and four peripheral walls 3, 3', 3''.

One peripheral wall 3 has a bellows 4 as a thermally responsive body.
The fixing surface 4a is welded to a bottom plate 6 to which one end of a capillary tube 5 is welded, with the tip of the capillary tube exposed inside the bellows 4 using solder or the like. Although not shown, a temperature sensing portion is provided at the other end of the capillary.

A switch S is provided on the peripheral wall 3' relative to the peripheral wall 3. That is, a fixed contact terminal 7 and a movable contact terminal 8 extending both inside and outside are fixed to the peripheral wall 3', and the fixed contact terminal 7 is provided with a fixed contact 9.
A movable contact plate 11 having a movable contact 10 is fixed to the movable contact terminal 8 by caulking or the like in an electrically conductive state. A snap actuating plate 11a is provided inside the movable contact plate 11 by a notch as is known in the art, and a quick reversal spring 12 is provided between the movable contact plate 11 and the snap operating plate 11a. The peripheral wall 3' is further provided with a differential adjustment screw 13 for adjusting the contact spacing.

The movable surface 4b of the bellows 4 and the movable contact plate 11 to the snap operating plate 11a of the switch S are in a state of opposing each other, and there is a gap between them that controls the movement of the bellows 4.
An operating rod 14 is provided for transmitting the signal to the user. That is, the head 14a at one end of the operating rod 14 is connected to the bellows 4.
The locking portion 14b at the other end is connected to the snap operating plate 11a, and in conjunction with the action of a leaf spring to be described later, the movement of the bellows 4 is transmitted to the switch S to open and close it. At this time, the operating rod 14 is supported and guided by the groove 15a of the partition wall 15.

A leaf spring 16 is provided between the bellows 4 and the switch S to counteract the movement of the bellows 4 and set the controlled temperature of the controlled portion. The leaf spring 16 is a rectangular thin spring plate having a constant width and is bent into an arcuate portion 1.
6a, the long side actuating part 16b and the short side set part 16c are integrally formed into a deformed U-shape, and an insertion hole 16d is formed in the middle part of the long side actuating part 16b.
is formed, and in the installed state, the long side actuating portion 16b
The end portion 16e contacts a fulcrum 15b protruding from the partition wall 15 in the direction of the peripheral wall 3 that supports the bellows 4, and the peripheral edge of the insertion hole 16d is operated while the operating rod 14 is loosely fitted into the insertion hole 16d. It opposes the bellows 4 via the operating rod 14 by abutting against the head 14a of the rod.

A drive piece 17a formed by bending a part of the sliding adjustment plate 17 comes into contact with the short side set portion 16c of the leaf spring 16, and the protrusion 17a ₁ engages in the hole 16c ₁ . The sliding adjustment plate 17 is located in the recess 1 of the front wall 1 of the upper housing A ₁
A is provided so as to be movable in the axial direction of the operating rod 14, and an elongated hole 17b facing in the moving direction is provided inside, and the bearing portion 1b of the camshaft 18 is located inside the elongated hole 17b. Although not shown, the drive piece 17a passes through a hole provided in the front wall 1. As a result of the above, the sliding adjustment plate 17 becomes the leaf spring 1.
It will be located on the side in the direction intersecting the direction of extension of 6.

An engagement protrusion 17c is erected at one end of the elongated hole 17b of the sliding adjustment plate 17, and a cam plate 19 provided on the camshaft 18 engages with the engagement protrusion 17c.

In the rear casing A ₂ , a load adjustment screw 20 for a plate spring is screwed into the bellows side peripheral wall 3 so as to be able to move forward and backward, and its inner end abuts against the fulcrum 15 b at the end 16 e of the long side operating portion 16 b of the plate spring 16 . It is coupled further outward than the section.

21 is a metal lid plate that covers the front wall 1, and the bellows 4 is attached to the lid plate 21.
Connecting plates 21a, 21a are provided on opposite peripheral walls 3'', 3'' in a direction intersecting the mounting peripheral walls 3, 3' of the switch S, and the connecting plates 21a, 21a are bent.
At the end of 1a, the peripheral wall 3'' of the rear casing _A2 ,
The caulking connecting pieces 21b, 21b, which position the connecting protrusions 22, 22 formed on the outer surface of the 3'' inside, are successively provided, and when assembled, the caulking connecting pieces 21
By caulking the ends of b, 21b to the connecting protrusions 22, 22, the cover plate 21 is attached to the housing A.
At the same time, ensure that the front and rear casings A ₁ and A ₂ are secured together.

An insertion hole 21 for the camshaft 18 is provided in the center of the cover plate 21.
c is formed, and outwardly protruding mounting plate portions 21d are successively provided on both sides thereof. Therefore, the camshaft 18 is connected to the hole 21c of the cover plate 21 and the bearing part 1 of the front wall 1.
It is held in a stable posture by b.

In the above configuration, the gas pressure corresponding to the temperature of the temperature sensing part is transmitted into the bellows 4 through the capillary tube 5, and the pressure inside the bellows and the load of the leaf spring 16 oppose each other through the operating rod 14, and the pressure inside the bellows is The actuating rod 14 moves in the axial direction due to the difference in the load between the actuating rod 14 and the leaf spring, and the movement of the actuating rod 14 is transmitted to the switch S, which drives the snap actuating plate 11a, thereby moving the reversing spring 12 to the movable contact plate. Contacts 9 and 10 are opened and closed via 11.

The operating temperature is set by moving the adjusting screw 20 forward and backward with the cam plate 19 of the camshaft 18 set at a constant position, and adjusting the spring load on the bellows 4 to reach an appropriate temperature within the adjustable temperature range. The operating temperature is set, and the off-point operating temperature is set by moving the differential adjustment screw 13 back and forth.

In this state, it is incorporated into refrigerators, room air conditioners, etc. After installation, the operating temperature can be set by rotating the cam shaft 18 and adjusting the sliding adjustment plate 1 using the cam plate 19.
7, and the short side set portion 16c of the leaf spring 16 is controlled by the driving plate 17a to form the arcuate bent portion 16a.
This is done by changing the degree of bending.

As described above, the present invention allows the bellows and the switch to face each other and transmits the movement of the bellows to the switch via the operating rod that moves in the axial direction, thereby simplifying the mechanism while allowing the bellows and the switch to be separated from each other. In addition, the movement can be transmitted accurately, and since the shape of the arcuate bent portion is changed using the U-shaped leaf spring, the load acting against the bellows can be effectively and appropriately set.

In addition, in the present invention, since the sliding adjustment plate is provided on the side in the extension direction of the leaf spring and adjusted by the cam, the depth of the housing from the cam axis direction, which is the adjustment side, during use can be greatly reduced. The flat and compact shape makes it easy to assemble into equipment such as refrigerators.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the thermostat according to the present invention, Fig. 2 is a left side view of the same as above, Fig. 3 is a right side view, Fig. 4 is a diagram of the internal mechanism with the front casing removed, and Fig. 5 is FIG. 2 is a sectional view taken along the line 2, FIG. 6 is an exploded perspective view of the main parts, and FIG. 7 is a perspective view of the leaf spring. A... Housing, S... Switch, 4... Bellows, 14... Operating rod, 16... U-shaped leaf spring, 1
7...Sliding adjustment plate.

Claims (1)

[Claims] 1. A bellows and a switch are provided in a housing facing each other, an operating rod is provided between the bellows and the switch, and the movement of the bellows is transmitted to the switch by axial movement of the operating rod, so that the bellows and the switch are A modified U-shaped leaf spring consisting of a short side set part and a long side actuating part is provided in between and connected through an arcuate bent part in a direction intersecting the actuating rod, and the long side actuating part of the leaf spring is The actuating rod is engaged to apply an opposing load to the bellows, the driving piece of the sliding adjusting plate is brought into contact with the set portion of the short side of the leaf spring, and the sliding adjusting plate is moved by the cam plate to create an arc shape. A thermostat characterized in that the opposing load is set by changing the shape of the bent portion. 2. A bellows and a switch are provided in the housing in opposition to each other, an operating rod is provided between the bellows and the switch, the movement of the bellows is transmitted to the switch by axial movement of the operating rod, and the operating rod and the switch are connected between the bellows and the switch. A modified U-shaped leaf spring is provided, which is composed of a short side set portion and a long side actuating portion that are connected in intersecting directions via an arcuate bent portion, and the long side actuating portion of the leaf spring is engaged with the actuating rod. A sliding adjustment plate is provided on the side in the direction intersecting the extension direction of the leaf spring and moves in the direction of the actuating axis by operating the cam plate, and the driving piece is moved to the short side of the leaf spring. 1. A thermostat, characterized in that the counter load is set by changing the shape of an arcuate bent part when a cam plate is operated, the thermostat being brought into contact with a part to be set.