JPS6050017B2 - Band-operated temperature switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature switch that uses two reversible bimetals, that is, two jumping plates, and performs band operation in which the contacts are kept closed or open only in a certain arbitrary section, and is particularly applicable to automobile cooling. The present invention relates to a band-operated temperature switch suitable for sensing water temperature.

A band-operated temperature switch using two different jumping disks as heat-sensitive elements is known, for example, from Utility Model Application No. 47-
It is shown in No. 24565 and is publicly known.

In addition, as a similar example to this known example, one manual return type jumping disk and one automatic return type jumping disk are combined, and the switch opens at a certain temperature or below.
A type of temperature switch that is repeatedly closed and once the temperature reaches a certain temperature or higher, the switch remains open or closed is disclosed in Japanese Utility Model Application No. 48-22166 and Utility Application No. 49-49.
33855. In all of these methods, the central part of the jumping disk installation part provided in the case is a concave surface, so in order to perform band operation using the minute displacement when the jumping disk is reversed, two steps are required. Among the two jumping disks, the one with a higher set temperature is installed so that its low expansion side metal faces the bottom of the case, and the jumping disk with a lower set temperature is installed so that its high expansion side metal is at the set temperature. should be placed opposite the higher expansion side metal of the higher jumping disk.

In a band-operated temperature switch with a jumping disk installed in this way, when the one with the lower set temperature of the two jumping disks reverses, the jumping disk is transferred from the movable plate via the transmission pin. Since the pressure transmitted to the jumping disk is always applied, the shifting occurs at a temperature lower than the inversion temperature of the single jumping disk, and the pressure transmitted from the movable plate is the distance from the base reference plane to the jumping disk, the base reference plane Since the operating temperature at this low temperature varies greatly depending on the precision of parts such as the distance from the center of the movable plate to the length of the transmission pin, the operating temperature at this low temperature varies widely.In particular, the operating temperature tolerance on the low temperature side is strictly regulated for automotive band operating types. The drawback was that it was not suitable for temperature switches.

The object of the present invention is to have a small temperature tolerance on the low-temperature side operating temperature,
An object of the present invention is to provide a band-operated temperature switch with excellent thermal responsiveness.

In order to achieve this object, the present invention uses a high-temperature side jumping plate that operates in reverse at high temperatures and a low-temperature side jumping plate that operates in reverse at low temperatures as heat-sensitive elements, and allows these jumping plates to be inserted into each other with almost no play. In a band-operated temperature switch housed in a hollow part for installing a jumping plate of a case having an inner peripheral surface shape, a protrusion is provided at approximately the center of the bottom of the case where both the jumping plates are installed, and the jumping plate is installed on the high temperature side. Place the plate on the protrusion with its low expansion metal side facing the bottom side of the case, and place the low temperature side jumping plate on its low! By stacking it on top of the high temperature side jumping plate with the expansion metal side facing the bottom side of the case, and making sure that the convex surfaces of both jumping plates both face the bottom side of the case when the temperature is sufficiently low, The present invention is characterized in that the spring pressure of the movable plate is not applied in the initial state when the low-temperature side jumping plate reverses, and that heat transfer from the case to the jumping plate is improved.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 shows an embodiment of the present invention, the characteristics of which are as follows:
As shown in FIG. 2, when the temperature rises, the contact closes only between the low-temperature operating temperature Tll and the high-temperature operating temperature Tl2, and remains open in other temperature states.

In addition, when the temperature drops, like a general temperature switch, it has hysteresis corresponding to each operating temperature, and the return temperature T2l
, T22, and the contacts close only between them. A band-operated temperature switch with such temperature characteristics is made of two heat-sensitive elements with different temperature characteristics, as shown in Figure 1.
a case 3 made of metal and having a threaded portion 3A suitable for attachment to the engine thermostat housing; Base 4 molded from thermosetting resin
A contact mechanism section 7 is provided on the lower end surface of two terminals 5 and 6 that are integrally embedded in the terminal, and solder is applied to the tips 5A and 6A of the terminals 5 and 6 in order to take out the open/close signals of the contacts and the outside. It is composed of lead wires 8 attached.

Here, the base 4 and the contact mechanism section 7 configured on the lower surface thereof are caulked by the caulking section 3C of the case 3 via the O-ring 9 using the stepped section 3B of the case 3 as a stopper. It is fixed with good sealing performance.

Further, the connection portion between the terminals 5 and 6 and the lead wire 8 is surrounded by a tube 10 made of an insulating material, and an adhesive 11 is applied to the inside of the tube 10 and the upper surface of the base 4 to improve sealing performance. The portion 4A is filled with the liquid. Next, the configurations of the jumping disks 1 and 2, the case 3, and the contact mechanism section 7, which are the heart of the band type temperature switch, will be described in detail.

FIG. 3 is a detailed view of the jumping disks 1 and 2, the case 3, and the contact mechanism section 7. The inside of the case 3 has a hollow part 12 having a larger diameter and a hollow part 12 having a larger diameter in order to prevent electrical continuity between the knurled parts 5B and 6B of the terminals 5 and 6 embedded in the base 4 and the case 3. A jumping disc installation hollow part 13 having a diameter into which the jumping discs 1 and 2 can be inserted with almost no play is provided below the jumping disc installation hollow part 1.
A protrusion 14 having a height approximately equal to the initial displacement position of the jumping disk is provided at the center of the bottom of the disc 3, and a shallow recess 15 is provided at the center of the protrusion.

In the case 3 configured as described above, the jumping disk 1 which performs the reversal operation at the higher temperature of the two jumping disks 1 and 2 when the ambient temperature is sufficiently low is installed.
Low expansion gold with a convex shape. A jumping disk 2, which is installed so that its metal side faces the protrusion 14 and is in contact with and supported by the peripheral edge 15A of the recess 15, and performs a reversing operation at a lower temperature, has its low expansion metal side facing the jumper. It is placed on the ping disk 1 so as to face the same direction as the convex surface of the ping disk 1.

The contact mechanism section 7 is arranged on the jumping disk arranged in this way.

The contact mechanism section 7 includes a fixed contact 16 fixed to the lower end surface of a terminal 5 embedded integrally in the base 4, a movable plate 1 fixed to the lower end surface of the other terminal 6, and made of a material with excellent conductivity.
7. A movable contact 18 fixed to the tip of the movable plate 17 so as to face the fixed contact 16, and the movable plate 1
The displacement of the jumping disk is inserted and fixed into the small hole 17A in the central part of 7 and the movable contact 18 is
It is constituted by a button 19 that transmits information to the user.

Further, the contact mechanism section 7 protrudes downward in a cylindrical shape integrally with the base 4 and is surrounded by a partition wall 21 having a cutout section 20. The outer diameter is such that it can be fitted onto the inner surface of 13 without play.

FIG. 4 shows a lower perspective view of the base 4, the contact mechanism section 7, and the partition wall 21. As shown in FIG.

The band-operated temperature switch configured as described above performs the following operations depending on changes in engine cooling water temperature.

Figures 5 to 7 show the states of the jumping discs 1, 2 and the contact mechanism section 7 due to changes in engine cooling water temperature. Figure 5 shows the state where the cooling water temperature is sufficiently low,
The figure shows that the cooling water temperature is equal to or higher than the low-temperature side operating temperature Tll and the high-temperature side operating temperature Tll. In the following state, FIG. 7, the cooling water temperature is at the high operating temperature Tl.

Each of the above situations is shown below. In this way, when the cooling water temperature is sufficiently low, the convex surfaces of the two jumping disks 1 and 2 are in the same direction and overlap, so the low temperature side jumping disk 2 and the button 19 are not in contact with each other. First, the contacts 16 and 18 are in an open state.

However, the engine cooling water temperature rises, and the low temperature side operating temperature T
When reaching 11, the jumping disc 2 suddenly reverses, hits the button 19 while being supported by the peripheral edge of the jumping disc 1 installed below, and momentarily moves the movable plate 17. and simultaneously lift contact 16.
, 18 are closed. Further, when the engine cooling water temperature rises and reaches around the high-temperature side operating temperature Tl2, the high-temperature side jumping disk 1 rapidly performs a reversal operation, and its peripheral edge moves to the case bottom surface which is lower than the upper surface of the convex portion 14. Accordingly, the low-temperature side jumping disk 2 supported by the peripheral edge part stops pushing up the movable contact 18 via the button 19 to close the contact, and moves away from the button 19. , contact 1
6 and 18 are in the open state again.

It will be obvious that band operation is performed in exactly the same manner when the cooling water temperature decreases.

As described above, by providing the protruding portion 14 at the bottom of the hollow portion 13 for installing the jumping disk of the base 4, and placing the jumping disks 1 and 2 thereon,
As shown in detail in FIG. 8, since the high-temperature side jumping disk 1 is always supported at the central portion on the low expansion metal side, the peripheral edge portion 1 supporting the jumping disk 2
A large displacement δ can be obtained, and this displacement δ is the same as that of the jumping disk 1 after the low-temperature side jumping disk 2 is reversed.
When the contact point is reversed, the amount is equal to the displacement of the point 2A on the convex surface of the jumping disk 2, which has the great advantage of ensuring reliable operation when changing the contact from the closed state to the open state. By installing the five jumping disks 1 and 2 on the convex portion 14 at a sufficiently low temperature so that the convex surfaces of the five jumping disks face the same direction and overlap each other, the low-temperature side jumping disk 2 is in the initial state during reversal operation. Since the spring pressure of the movable plate 17 is not applied, the reversal temperature 0T1'' of the jumping disk 2 and the operating temperature Tll of the switch match, and by controlling the temperature tolerance only for the reversing temperature T1'' of the jumping disk 2, The tolerance of the low-temperature side operating temperature Tll can be suppressed to a narrow range regardless of the tolerance of each component, and there is an advantage that characteristics suitable for a temperature switch operating in an automobile band can be obtained.

On the other hand, as already shown in FIG. 6, the high-temperature operating side jumping disk 1 is always subjected to movable plate pressure via the button 19 when the low-temperature side jumping disk 2 is inverted. Figure 9 shows an example of the change in temperature characteristics when pressure f is applied to the center of the jumping disk, and Figures 10A and b show the operating method of the band-operated temperature switch and the jumping disk incorporated therein. A schematic diagram of the temperature characteristics of In this way, when the jumping disk is constantly subjected to pressure, the reversal temperature of the jumping disk changes depending on the magnitude of the pressure, and moreover, the reversal temperature of the jumping disk is always lower than the reversing temperature of the single jumping disk.

Therefore, when incorporated into a temperature switch, as shown in FIG. 10, the high temperature side operating temperature Tl2 of the temperature switch is
The reversal temperature T of the high-temperature side jumping disk is lower than T, and the pressure of the movable plate 17 is lower than the terminal 5,
6, the length of the button 19, and the length of the base 4.
This operating temperature tolerance on the high temperature side varies depending on the dimensional accuracy of each component, such as the distance between
It has to be a large value compared to the low-temperature side temperature tolerance. Note that the shaded area in FIG. 10a indicates the range of variation due to component tolerances. However, as shown in FIG. 11, a shallow recess 15 is provided at the center of the protrusion 14, and when the jumping disk 1 is under the pressure f of the movable plate 17, the peripheral portion 15A of the recess 15 is By supporting the jumping disk 1 at a lower temperature, the moment Mr.
As a result, the difference between the inversion temperature T1'' of the jumping disk 1 and the high temperature side operating temperature Tl of the temperature switch can be reduced as a whole, and temperature variations due to component precision can be reduced. It has the excellent effect of being able to be made smaller.

The experimental results regarding this are as shown in the curve A of FIG. 12, and a clear difference can be seen compared to the curve B shown with and without the recess 15.

In addition, since the jumping disk is supported on the line,
It is also advantageous against vibration.

Furthermore, by installing the high-temperature side jumping disk 1 in contact with the case 3, thermal responsiveness can be improved.

The reason for this is explained below. That is, the engine cooling water temperature heats the inside of the case from the protrusion 14 and the side surface of the case 3, but due to the relationship between heat capacity and heat transfer coefficient, the air sealed inside the case is difficult to heat, and according to experiments. As time passes, the engine cooling water temperature, the temperature of the convex portion 14 of the case 3, and the temperature of the air layer inside the case change as shown by curves C, D, and E in FIG. 13, respectively.

As shown in this figure, when the engine cooling water temperature is relatively low, the temperature difference with the outside is small, so there is almost no difference between the cooling water temperature and the internal/internal air layer temperature. It can be seen that the difference arises because the heat dissipation to the For this reason, the high temperature side jumping disk 1 is installed in contact with the protrusion 14, which has a small temperature difference with the cooling water temperature, and the low temperature side jumping disk 2 is placed on top of it. This has the advantage that the overall thermal response can be improved.

Further, the cylindrical partition wall 21 protruding downward from the base 4 is provided, and when only the low-temperature side jumping disk 2 of the two jumping disks is reversed, the peripheral edge of the partition wall 21 is the end portion 21A of the partition wall 21. By arranging the jumper discs to be at approximately the same position as the jumper discs, it is possible to prevent the jumping disc from dancing and hitting the button 19 during vibration, thereby preventing the contacts from chattering.

Furthermore, the band-operated temperature switch with this structure has the great advantage of being able to obtain the characteristics of conventional non-band-operating temperature switches by changing the shape of only a few parts and adding one new jumping disk. It is very advantageous in terms of price.

FIG. 14 shows another embodiment of the invention. In this embodiment, a fixed plate 23 having a fixed contact 22 fixed to its tip is fixed to the terminal 5, and a contact pressure F is applied to the terminal 6 at its tip with respect to the fixed contact 22 in an initial state.

By fixing a movable plate 25 having a stepped portion and having a movable contact 24 fixed so as to be in contact with each other, when the engine cooling water temperature rises, the low-temperature side operating temperature Tll and the high-temperature side operating temperature Tl are fixed. The contacts are designed to open only between. This method of operation is shown in FIG. In addition, in the above embodiment, the jumping plate is circular,
That is, although a jumping disk is used, the shape is not limited to this, and a rectangular jumping plate, for example, may also be used. Furthermore, the entire bottom surface of the convex portion provided on the bottom of the case can be formed into a convex arc surface or a chevron shape, and the jumping plate can be supported at the raised center portion. As explained above, according to the present invention, the protrusion is provided at approximately the center of the bottom of the case, and the high-temperature side jumping plate is placed on the protrusion with the low expansion metal side facing the bottom of the case. Place the low-temperature side jumping plate on top of the high-temperature side jumping plate with its low-expansion metal side facing the bottom of the case. Since both of them face the bottom of the case, the spring pressure of the movable plate is not applied in the initial state when the low-temperature side jumping plate is reversed, and heat transfer from the case to the jumping plate is improved. As a result, a band-operated temperature switch with less variation in operating temperature on the low-temperature side and excellent thermal responsiveness can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a band-operated temperature switch according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of its operation, FIG. 3 is a detailed sectional view of the jumping disk, case, and switch mechanism, and FIG. The figure is a downward perspective view of the contact mechanism and the bulkhead. Figures 5 to 7 are state diagrams of the jumping disk and contact mechanism corresponding to the engine cooling water temperature. Figure 8 is the installation of the jumping disk on the protrusion. Figure 9 is a characteristic diagram showing the changes in the inversion temperature characteristics when pressure is applied to the center of the jumping disk, and Figures 10A and b are the operating characteristics of the band-operated temperature switch. Operation explanatory diagram showing the difference in characteristics of the jumping disk incorporated in the 11th
The figure is a detailed cross-sectional view showing the state of the jumping disk supported by the convex part, Figure 12 is a characteristic diagram showing the effect of this embodiment, and Figure 13 is a graph showing temperature changes in various parts of the band-operated temperature switch over time. FIG. 14 is a sectional view of a band-operated temperature switch according to another embodiment of the present invention, and FIG. 15 is an explanatory diagram of its operation. 1... High temperature side jumping disk, 2...
... Low temperature side jumping disk, 3 ... Case, 14 ... Convex part, 15 ... Concave part.

Claims (1)

[Scope of Claims] 1. A high-temperature side jumping plate that operates in reverse at high temperatures and a low-temperature side jumping plate that operates in reverse at low temperatures are used as heat-sensitive elements, and these jumping plates are connected to an inner circumferential surface into which these plates fit with almost no play. In a band-operated temperature switch housed in a jumping plate installation hollow part of a case having a shape, a protrusion is provided at approximately the center of the bottom of the case where both the jumping plates are installed, and the high temperature side jumping plate is The bottom temperature side jumping plate is placed on the protrusion with its low expansion metal side facing the bottom side of the case, and the bottom temperature side jumping plate is placed on the high temperature side jumping plate with its low expansion metal side facing the bottom side of the case. A band-operated temperature switch characterized by a stacked pin plate. 2. A high-temperature side jumping plate that operates in reverse at high temperatures and a low-temperature side jumping plate that operates in reverse at low temperatures are used as heat-sensitive elements. In a band-operated temperature switch housed in a hollow part where the jumping plates are installed, a raised part is provided at approximately the center of the bottom of the case where both jumping plates are installed, and a recessed part is provided near the center of this raised part. A side jumping plate is placed on the convex portion with its low expansion metal side facing the bottom side of the case, and the concave portion supports the central portion of the convex surface of the high temperature side jumping plate, and the low temperature side A band-operated temperature switch characterized in that a jumping plate is stacked on top of the high temperature side jumping plate with the low expansion metal side facing the bottom side of the case.