JPS6144372B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to improvements in bimetallic thermostatic switches that are responsive to several temperatures.

BACKGROUND OF THE INVENTION Bimetallic thermostats that respond to several temperatures are known. However, this conventional design typically has a temperature response limited to two points and includes a pair of coaxially arranged calotte-shaped or dish-shaped disk elements whose curvature is reversed. Mechanically actuating the electrical contacts at a predetermined operating temperature.

In these known devices, when a plate-shaped temperature sensing element provided at one end of the switch housing is reversed at operating temperature, the reversal action is transmitted via a mechanical transmission member to a movable plate provided at the other end of the housing. The signal is transmitted to the contact and opens the contact. For this reason, not only does the size of the entire device increase, but also the presence of intermediate members inevitably reduces accuracy. Increasing accuracy requires a highly precise mechanical structure, which is relatively expensive and bulky.

(Object of the Invention) The object of the present invention is to obtain a thermostat that responds to temperatures at several points, which has a simple, compact, and economical structure and incorporates detection devices that respond to temperatures at two or more points in one unit. That's true.

The present invention describes temperature sensing devices or thermostatic switches that implement two types of contacts: a "normally open" contact and a "normally closed" contact. As an example, these two types will be explained as devices that respond to three points of temperature, but as is clear from the description of the present invention,
This system can be modified to provide temperature sensing at any number of points for selected response temperatures.

The invention will now be described with reference to two preferred embodiments. These are shown for illustrative purposes only.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown a basic "normally open" detection and switch configuration according to a first embodiment of the present invention. This device has a substrate 10 on which a first metal track 11 is formed in a known manner on a protrusion substantially in the center of a circular sheet 12, and a second metal track 13 is likewise formed on this substrate 10 in a known manner. It is formed by a method. The metal tracks 11 and 13 form part of two branches of a circuit which are closed by actuation of a carrot-shaped or dish-shaped bimetallic element 14 of known design. The carrot-shaped bimetallic element 14 is held in position by a cover element 15 which is fastened to the substrate 10 by thermally or ultrasonically riveted pins 16 and 17. A layer 18 of electrically conductive elastomer is disposed between elements 10 and 15 to form a stretchable, flexible, continuous contact between track 13 and the circumference or top surface of carrot-shaped element 14. When the carrot element conventionally reverses its bending at a predetermined snapover temperature, the circuit between track 13 and track 11 is closed. The response temperature of the other discs in the device is selected by the carrot element 14 used.

Another embodiment of the present invention, a type of sensing and switching device having a "normally closed contact" configuration, is shown in FIG. Two conductive tracks 21 and 22 are made on the substrate 20 and form two parts of a normally closed circuit by means of a carrot-shaped bimetallic disk 23. This carrot-shaped bimetallic disk 23 is held against the conductive track by a spring 24 provided in the sheet 25 of the insulating substrate 26. Under the situation shown in FIG. 2, the circuit is closed between tracks 21 and 22. At the response temperature, the carrot-shaped bimetallic disk 23 reverses its bending and forms a rod or protrusion 27.
In this way, the circuit between tracks 21 and 22 is broken.

Two types of thermostat switch devices of the present invention each having three response temperatures will be described with reference to FIGS. 3 to 9 and FIGS. 10 to 15.

In the set of FIGS. 3 through 9, FIG. 3 has three point response temperatures, and the sensing unit using the sensing and switching apparatus shown in FIG. 1 is designated as a whole at 100. The unit 100 has a lower substrate 101 on which are arranged four terminals 102, one "common" and three "active". The upper substrate or lid 103 is tightly secured to the lower substrate 101. The upper substrate has recesses or housings 104, 105 and 106 (best seen in FIGS. 8 and 9) that receive carrot-shaped bimetallic disks 99. The disks 99 not shown in FIG. 3 but shown in FIG. 4 each have a response temperature and are arranged so that their bending direction is reversed at that temperature. As will be understood, the three disks 99 used in the device 101 are installed so that their curvature reverses at different temperatures. Although not shown in Fig. 3, the conductive rubber layer shown in Fig. 4 is the upper substrate 1.
03 in shape, and is disposed between the substrates 101 and 103 and is in contact with the flat surface of the upper substrate 103 and the housing or the concave surfaces of the recesses 104, 105, and 106, and is installed in the recesses 104, 105, and 106. It engages with the normally convex side of the metallic disc 99.

Referring to FIGS. 5, 6 and 7, the lower substrate 101
I will explain about it. This substrate 101 has a recess 1 slightly smaller than the diameter of the bimetallic disk 99.
04a, 105a, 106a, and these depressions have protrusions 109, 110, 11 at their centers.
1. These protrusions 109, 110, 11
1 are electrically connected to conductive tracks 112, 113 or 114, respectively. The conductive tracks are connected to terminals 102 through grooves 115, 116 or 117 in substrate 101, respectively.

One of the terminals 102 is connected to a conductive plate or layer 118 on the substrate 101 to connect the two substrates 101 and 1.
Contact is made with the electrically conductive rubber layer 98 provided between 03 and 03. Plate 118 thus constitutes a "common" connection to disc 99.

When operating, if unit 101 is lower than any response temperature of disk 99, all contacts or switches of unit 101 are open. However, when the unit 101 is heated to reach the snap-over temperature of each bimetallic disc 99 in turn, the bimetallic discs form contact between the conductive rubber 98 and each protrusion 109, 110, 111, thereby “Common” terminal 1 connected to plate 118
02 and one of each "active" terminal 102.

Figures 3 to 9 show units that respond to temperatures at three points. However, it will be readily appreciated by those skilled in the art that this unit could easily be modified to respond to any number of different temperatures.

10 to 15 show a second preferred embodiment of the device according to the invention having a three point response temperature and using sensing and switching devices consistent with the device shown in FIG. .

10-15, another preferred embodiment according to the present invention is shown generally as a unit at 200 in FIG. This unit has a contact area 20, as will be explained further below.
2,203,204,205,206 and 20
A lower substrate 201 and an upper substrate 208 having 7
have. As shown in FIGS. 14 and 15, upper substrate 208 has housings or recesses 209, 210 and 211 in which bimetallic discs 212 are disposed, and inside recesses 209, 210 and 211. It is pressed against the lower substrate 201 by means of a spring 213 provided in a certain well 14.

As can be clearly seen in FIGS. 12 and 13, on the lower substrate 201 of insulating material are electrically separated conductive regions 215, 216, 217 and 218.
are arranged in a known manner, and as shown in FIG.
and 207. When disc 212 in device 200 is not activated, the ends of the bimetallic discs are interlocked and engage track 215.
The inner peripheral areas from 216 to 216, from 216 to 217, and from 217 to 218 are shorted. However, the bending of the disk 212 is reversed and the spring 213 (the first
When pressed with the pressure shown in Figure 1), the track 21
8 and 217, tracks 215 and 216, and tracks 216 and 217, respectively.

As seen in FIGS. 3 through 15, which describe various embodiments of the invention, the lower substrates of units 100 and 200 have holes 96 to facilitate coupling of pins 97 located on the upper substrate. Centering the bimetallic disk elements and connecting the two substrates together during assembly of the device can be achieved by thermally or ultrasonically riveting the ends of pins protruding from holes in the lower substrate. Serves a dual purpose.

(Effects of the Invention) According to the present invention, the dish-shaped bending element is configured to directly electrically connect or disconnect conductive tracks. Therefore, it is possible to omit the mechanical transmission member that transmits the reversal motion of the bending element as in the conventional device, which not only improves the precision of the operation but also simplifies the structure, making it possible to create an inexpensive, small and lightweight thermostat switch device. can be provided. In particular, when a plurality of bending elements that react at various different temperatures are combined into one device, the structure of the conventional device would be extremely complicated, but it can be easily realized with the present invention.

Although the invention has been described with reference to two preferred embodiments, these are given by way of example only and are not intended to limit the scope of the invention in any way. It will be readily understood that modifications of the type described above may be made by those skilled in the art without departing from the scope of the invention.

[Brief explanation of the drawing]

FIG. 1 is an enlarged partial cross-sectional view taken along the main axis of a switch device according to a preferred embodiment of the present invention. FIG. 2 is a partial cross-sectional view similar to FIG. 1 showing a switch device in another preferred embodiment of the invention. FIG. 3 is a plan view of a preferred embodiment of the invention including the switch device shown in FIG. FIG. 4 is a cross-sectional view taken along line 4--4 of FIG.
FIG. 5 is a plan view of the embodiment of the invention shown in FIG. 3, with the upper elements removed to show the device of FIG. FIG. 6 is a cross-sectional view taken along line 6--6 of FIG. FIG. 7 is a cross-sectional view taken along line 7--7 of FIG. 8 is a bottom view of the elements of the device of FIG. 3 which have been removed from FIG. 5; FIG. FIG. 9 is a cross-sectional view taken along line 9--9 of FIG. 10th
2 is a plan view of another preferred embodiment of the invention including the switch device of FIG. 2. Figure 11 is the 10th
FIG. 3 is a cross-sectional view taken along line 11-11 of the figure. 12th
The figure is a plan view of the embodiment of the invention shown in FIG. 10, with the upper elements removed to show the device of FIG. Figure 13 is line 13-1 in Figure 12.
FIG. 3 is a cross-sectional view along line 3; 14 is a bottom view of the elements of the device of FIG. 3 which have been removed from FIG. 12; FIG.
FIG. 15 is a cross-sectional view taken along line 15--15 of FIG. 14. 10, 101, 103, 201, 208...Substrate, 11, 13, 21, 22, 112-114,
215-218...Conductive track, 14, 23, 9
9,212...bimetallic element, 16,17,
97... Pin, 24, 213... Spring, 10
2,202 to 205,207...terminals.

Claims (1)

[Scope of Claims] 1. A dielectric first base member having a plurality of pairs of connecting devices fixed on a common plane; and a plurality of dish-shaped bending elements, the bending elements having a curved portion. when placed in one of the curved elements, said curved element engages and bridges each pair of said connecting devices, electrically connecting said pair of said connecting devices, said curved element When placed on the first base member in the common plane, the bending element bends in opposite directions on the first base member in the common plane to disengage and release each pair of connecting devices. a second relatively thin sheet of dielectric material fixed to the first base member and located in a plane on the first base; A switch device comprising a base member, wherein the first base member is a thin sheet-like member, and the dish-shaped bending element is formed from a thermostat metal, and is configured to operate at various temperatures selected within a temperature range to be monitored. The curved elements are configured to be movable with a snapping action of a selected one of the curved elements from one of the curved portions to another of the curved portions in response to the occurrence of a temperature change. A switch device characterized by: 2. The switch according to claim 1, wherein an elastic member is disposed between the first base member and the bending element, and biases the bending element toward one of the bending parts. Device. 3. According to claim 2, the first base member has a pair of first and second connecting plates formed as a common additional connecting means, and the resilient member connects the bending element and the second connecting plate. a flexible conductive member made of an organic material disposed to overlap and engage with the connecting plate, the second base member having the flexible conductive member electrically connected to the bending element; A switch device characterized in that it holds the flexible conductive member. 4. In claim 2, the bending element is disposed on the first base member, and when the bending element is located in one of the bending parts, the bending element is arranged on the first and second base members. When the pair of connecting plates are connected to each other, and the bending element is located in the other bending part, the bending element moves with respect to the first base member and connects the pair of the first and second connecting plates. A switch device characterized by opening the connection of.