US3728659A

US3728659A - Thermoelectrical switch

Info

Publication number: US3728659A
Application number: US00219708A
Authority: US
Inventors: L Brock
Original assignee: General Motors Corp
Current assignee: Motors Liquidation Co
Priority date: 1972-01-21
Filing date: 1972-01-21
Publication date: 1973-04-17
Anticipated expiration: 1990-04-17
Also published as: GB1368555A

Abstract

In a preferred form, this disclosure relates to a thermoelectrical switch having a housing means with terminal means adapted to be connected with electric circuit means, printed circuit means disposed within said housing means and adapted to be connected with said terminal means of said housing means, a piston-like contact carrier which is supported for movement adjacent said printed circuit means between circuit energized and circuit deenergized positions and having a grounded contact means disposed to engage said printed circuit means when said contact carrier is in its circuit energized position, spring means which biases the contact carrier in one direction within said housing, and thermally expansible means which acts in opposition to the bias of said spring means and effects movement of the contact carrier in the opposite direction within said housing means when its temperature is increasing from a first predetermined temperature toward a second predetermined temperature.

Description

United States Patent [191 Brock 1 Apr. 17, 1973 [54] THERMOELECTRICAL SWITCH [75] Inventor: Lynn S. Brock, Williamsville, N .Y.

[56] References Cited UNITED STATES PATENTS 1,307,086 6/1919 Dijkstra ..337/309 X 3,212,337 l0/1965 McCarrick ....337/3l5 X 3,149,455 9/1964 Daly et a1. ..337/3 15 X Primary ExaminerBernard A. Gilheany Assistant Examiner-D. A. Tone AttorneyW. E. Finken et a1.

[ ABSTRACT In a preferred form, this disclosure relates to a thermoelectrical switch having a housing means with terminal means adapted to be connected with electric circuit means, printed circuit means disposed within said housing means and adapted to be connected with said terminal means of said housing means, a pistonlike contact carrier which is supported for movement adjacent said printed circuit means between circuit. energized and circuit deenergized positions and having a grounded contact means disposed to engage said printed circuit means when said contact carrier is in its circuit energized position, spring means which biases the contact carrier in one direction within said housing, and thermally expansible means which acts in opposition to the bias of said spring means and effects movement of the contact carrier in the opposite direction within said housing means when its temperature is increasing from a first predeterminedtemperature toward a second predetermined temperature.

4 Claims, 6 Drawing Figures THERMOELECTRICAL SWITCH The present invention relates to a thermoelectrical switch assembly, and more particularly to a thermoelectrical switch assembly which has a contact carrier that is moved between circuit energized and deenergized positions by a thermally expansible means.

Heretofore, thermally responsive circuit controllers have been provided which comprise a plunger or piston member which is moved in response to the expansion of a thermally sensitive liquid to engage different contacts to close different electric circuits. For example, see U.S. Pat. No. 1,307,086. Thermally responsive actuators have also been provided which include spring biased plunger or piston members that are moved in response to expansion of a thermal sensitive material in order to shift the movable contact between two different fixed contacts to thereby close different electric circuits. For example, see U.S. Pat. No. 3,212,337. Further, thermally responsive switches have been provided comprising a bellows member with printed circuits thereon and which is vertically shiftable and horizontally rotatable within a housing with a pluralityof contacts positioned adjacent the bellows in order that electric circuits can be completed between different ones of the contacts according to the vertical and rotational movement made by the bellows. For example, see US. Pat. No. 3,027,435.

The present invention provides a new and improved thermoelectric switch which is of a relatively compact, simple and economical construction. Accordingly, a broad object of the present invention is to provide such a thermoelectric switch, and in which a piston-like contact carrier is moved in response to temperature variations to bridge and unbridge printed circuit contacts carried by a stationary housing to energize and deenergize electric circuits.

Another object of the present invention is to provide a new and improved thermoelectrical switch having a housing means which defines an inner chamber, a terminal means carried by the housing means and which is adapted to be connected with electric circuit means including the power source, printed circuit contacts disposed within the housing means and which are adapted to be connected with the terminal means of the housing means, a piston-like contact carrier which is supported within the housing means adjacent said printed circuit means for movement within the inner chamber between a circuit energized position and a circuit deenergized position and which also has a grounded contact means supported thereon, spring means for biasing the contact carrier in one direction within the housing, and a thermally expansible means which acts in opposition to the bias of the spring means and effects movement of the contact carrier in the opposite direction within the housing when its temperature is increasing from a first predetermined temperature toward a second predetermined temperature and also which allows the bias of thespring means to affect movement of the contact carrier in the one direction within the housing when its temperature is decreasing from the second predetermined temperature toward the first predetermined temperature whereby the contact carrier is moved between its circuit energized and circuit deenergized positions.

These and other objects of the present invention are accomplished in the preferred embodiment of the tion, and which has a first contact affixed thereto and a.

grounded second contact affixed thereto. The assembly further includes a spring means which extends between the first terminal means of the housing means and the first contact of the piston member for providing electrical continuity therebetween and which also serves to bias the piston member toward its low temperature position. The piston-like contact carrier is operatively connected with a thermally responsive power element having a thermally expansible material therein.

The thermally expansible material expands when the I temperature of the material is increasing from a first predetermined temperature toward a second predetermined temperature to cause the piston-like contact carrier to move in opposition to the bias of the spring means from its low temperature position toward its high temperature position. Also, the material contracts when the temperature in the material is decreasing from the second predetermined temperature toward the first predetermined temperature and thereby allows the bias of the spring means to effect movement of the piston-like contact carrier from its high temperature position toward its low temperature position.

The assembly also includes first and second circuit boards which are disposed within the inner chamber of the housing means adjacent the path of the piston member and which include first and second conductor means, respectively, printed in elongated strips along the path of said piston member. The first circuit board is connected in the second terminal means and the second circuit board is connected with the third terminal means. The first conductor means has portions disposed for the first contact on the piston member to slide in engagement therewith upon movement with the piston member between its low and high temperature positions to energize the first electric circuit means and also has portions thereof disposed for the first contact of the piston member to slide out of engagement therewith to deenergize the first electric circuit means. The second conductor means has portions disposed for the second contact of the piston member to slide in en gagement therewith upon movement of the piston member to energize the second electric circuit means and has portions thereof disposed for the second contact of the piston memberto slide out of engagement therewith to deenergize the second electric circuit means. I

These and other objects of the invention will become more apparent from the following description and drawings wherein:

FIG. 1 is a front elevational view with portions shown in section of a preferred embodiment of the present invention;

FIG. 2 is an end view of the preferred embodiment-of the present invention shown in FIG. 1;

FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 2;

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 1; and

FIG. 6 is a cross-sectional view taken along line 66 of FIG. 1.

As representing a preferred embodiment of the present invention, the drawings show a switch assembly 10 for simultaneously controlling the energization of various electrical devices as a function of the temperature of a source of heat. Although the switch assembly 10 can be used to control many different functions, it is particularly susceptible for controlling the energization in an automotive vehicle of an engine cold light, an engine hot light, a heater blower and a solenoid switch which controls the advancing and retarding of the spark by the distributor of the vehicle. Accordingly, the following detailed description will be directed to the use of the switch assembly in the above described context.

The switch assembly 10 broadly comprises a housing 12, a piston-like contact carrier 14 supported for rectilinear movement within the housing means 12, a spring means 16 which biases the piston member 14 in one direction, a thermally expansible means 18 which moves the piston 14 within the housing means 12 against the bias of the spring means 16, and a printed circuit means 20 on the housing 12 which is adapted to be engaged and disengaged by the piston-like contact carrier 14.

Referring to FIGS. 1 and 2, the housing means 12 is made from an electrical insulating material, such as a plastic, and consists of a pair of arcuately shaped

end walls

22 and 23 and a pair of

flat side walls

25 and 26 which define a noncircular elongated opening or inner chamber 28 therebetween. The

end walls

22 and 23 and the

side walls

25 and 26 have a continuous lip 30 adjacent their upper end which extends radially inwardly into the inner chamber 28. The lip 30 at its inner periphery definesa circular opening 32, as shown in FIG. 2. It should also be noted that the lower end of the housing 12, as shown in FIG. 1, has a radially outwardly extending annular lip 34.

The housing means 12 also includes a top member 36 which is positioned within the opening 32 at a location immediately adjacent the lip 30. The top or end member 36 has an axially extending upper portion 37 which is shaped generally complementary to and received within the opening 32, as shown in FIGS. 1 and 5, and has a radially extending flange 38 generally complementary in shape to and positioned within the inner chamber 28 of the housing means 12 and in an abutting relationship with the radial lip 30 thereof.

The top member 36 also includes a cylindrical projection 42 which extends axially from the inward facing side 44 of the top member 36 into the inner chamber 28. The top member 36 has a slot 46 therein which is L- shaped as viewed in cross-section, as shown in FIG. 1, and which extends radially within the inward facing side 44 and axially within the cylindrical projection 42 of the top member 36. The top member 36 also includes a slot 48 within the cylindrical projection 42 at a position diametrically opposite the L-shaped slot 46 and which has a portion thereof terminating at the radial flange 38. The slot 48 also has a portion 50 which extends into and thereafter radially outwardly within the radial flange 38.

Three terminals 52-54 project outwardly from the housing means 12 and are adapted to be electrically connected respectively with an engine cold light, an engine hot light, and a heater blower (none of which are shown) and which are in turn electrically connected with a power source (not shown). The terminals 52-54, as shown in FIG. 1, have male end portions 57 which are received within complementary shaped holes 59 extending completely through the top member 36 and which are staked adjacent the bottom of slot 46 to retain the terminals 52-54 upon the top member 36. Another terminal 61 has an elongated male end portion 62 which is received within a complementary shaped hole 63 extending through the top member 36 to the inward facing side 44 and which is also staked to retain the terminal 61 upon the top member 36. The terminal 61 is adapted to be connected directly with the power source (not shown). Yet another terminal 65, which is adapted to be electrically connected with a solenoid valve (not shown) which controls the advancing and retarding of the spark by the distributor (not shown) is similarly mounted upon the top member 36 with its end portion 66 staked adjacent the bottom of the portion 50 of the slot 48.

The terminals 52-54 have three elongated strips 68-70, respectively, which have inner flat portions 71 secured to the staked inner ends 57 and extending radially along the bottom of the slot 46 to a bent end portion 72 which is self-biased toward the side wall 25 of the housing means 12. The terminal 61 also includes an elongated strip 73 with an inner portion 74 secured to the staked end 62 thereof and extending radially along the inner side 44 of the top member 36 to a bent end portion 75. Similarly, the terminal includes an elongated strip 76 secured to its staked inner end 66 and which extends along the bottom of the radial portion 50 of the slot 48 to a bent end portion 77 which is selfbiased toward the wall 26 of the housing means 12.

Referring to FIGS. 1 and 6, the contact carrier 14 generally comprises a head 78 and a stem 80. The head 78 is generally complementary in shape to the non-circular inner chamber 28 of the housing means 12 and is supported therein for linear movement in opposite directions within the inner chamber 28 of the housing means 12. The head 78, which is made from an insulating material, has a radially outwardly extending flange 82 upon which is fixedly mounted a spring contact 84 which extends radially outwardly along the inward facing side 82a of the flange 82, which then extends axially along the end of the flange 82b and which has a reversely bent outer portion 86 which is self-biased toward the side wall 26 of the housing means 12. The head 78 also carries a second contact 88 which extends radially outwardly within a radial groove 90 in the bottom side 92 of the head 78 and which has a reversely bent end portion 94 immediately adjacent the end 82b of the flange 82 and which is self-biased toward the side wall 25 of the housing means 12.

The stem 80 of the contact carrier 14 is a generally cylindrical, elongated member which has a narrow upper end 95 received within a complementary shaped hole 96 extending through the central portion of the head 78. The stem 80 extends downwardly from the head 78, as shown in FIG. 1, and is supported within the thermal expansible means 18, as will later be described. The stem 80 terminates in a conical end portion 98. It should be noted that the second contact 88 of the member 14 has a hole therethrough complementary in shape to the upper narrowed end 95 of the stem 80 and is received thereon, such that the second contact 88 is fixedly retained upon the piston member 14 between the head 78 and the stem 80.

The contact carrier 14 is movable between a first position adjacent the lower end of the inner chamber 28 of the housing means 12, as shown by the solid lines in FIG. 1, a second position immediately above the first position, as shown by the dotted lines in FIG. 1, a third position immediately above the second position, as shown by the phantom lines in FIG. 1, a fourth position immediately above the third position, as shown by the dashed lines in FIG. 1, and a fifth position adjacent the upper end of the inner chamber 28, as shown by the dash-dot lines in FIG. 1.

The spring means 16, which could be any suitable variety of spring, is herein shown as a coiled compression spring which has its upper end 102, as shown in FIG. 1, in abutting engagement with the inward facing side 44 of the top member 36 and engaged with the elongated strip 73 of the terminal 61. In this respect, the spring 16 is electrically connected with the power source (not shown). The lower end of the spring 16 is in an abutting relationship with the inward facing side 82a of the flange 82 of the head 78 and with the first contact 84 carried by the head 78. In this respect, the

spring 16 serves to bias the contact carrier 14 away from the top member 36 of the housing means 12 and the terminals 52-54, 61 and 65, as shown in FIG. 1, and also serves to provide electrical continuity between the terminal 61 connected with the power source (not shown) and the first contact 84 carried by the contact carrier 14. It is significant to note that the upper end 102 of the spring 16 is not engaged with the elongated strips 68-70 and 76 of the terminals 52-54 and 65 which are disposed within the

slots

46 and 48 of the top member 36 and also that the lower end 106 of the spring 16 is not engaged with the second contact 88 which is disposed on the bottom side of the head 78 of the contact carrier 14.

The thermally expansible means 18 or power element serves to move contact carrier 14 within the inner chamber 28 of the housing means 12 in response to the temperature of the heat source (not shown). The power element 18 includes a generally cylindrical, elongated housing 108 of a material having a relatively high thermal conductivity, such as brass. The housing 108 has a bottom wall 110 and an annular sidewall 112 which extends upwardly, as shown in FIG. 1, from the bottom wall 110 and which defines therewith a cylindrical inner chamber 113. The side wall 112 terminates adjacent its upper end in a radially outwardly projecting flange l 14 and an annular side flange 116 which extends axially from the radial flange 76 to the front of the generally circular opening 118 into the housing 108. The power element 18 also includes a flexible diaphragm 120 which is generally cylindrical in shape and which extends axially within the chamber 113 from the bottom wall 110 to a position adjacent the radial flange 114. It is significant to note that the diaphragm 120 has a diameter substantially smaller than the diameter of the inner chamber 113. The diaphragm 120 terminates adjacent its upper end in a radially outwardly extending flange 122 which extends over the radial flange 114 of the housing 108. The diaphragm 120 defines a generally cylindrical inner chamber 124 which extends axially therein from an open end adjacent the upper end of the diaphragm 120 and which terminates in a conical portion 126 adjacent the lower end of the diaphragm 120. The inner chamber 124 of the diaphragm 120 is substantially complementary in shape to the stem of the contact carrier 14 and has the stem 80 slidably received therein.

The power element 18 also includes a metallic header 128 which is shaped generally complementary to the opening 118 defined by the side flange 116 and which is received therein in abutting engagement with the radial flange 122 of the diaphragm and the radial flange 114 of the housing 108. The bottom side 130 of the header 128 has a central, circular recess 131 which is generally complementary in shape to the radial flange 122 of the diaphragm 120 and which has a groove therein which extends circumferentially about the recess 131. The header 128 also includes a second central recess 134 within the recess 131 of the bottom side 130 and a central hole 136 which extends from the recess 134 completely through the header 128. The

recess 134 receives an annular seal 138 of some materi al having a relatively low coefficient of friction, such as Teflon. Further, an annular contact plate 139 is received within the side flange 116 of the housing 108 and is positioned immediately above and in an abutting relationship with the header 128. The contact plate 139 has a central opening 139a therethrough defined by an axially curled flange 13%. The stem 80 extends from the inner chamber 124 of the diaphragm 120, through the annular seal 138, through central hole 136 in the header 128, and through the central opening 139a in the contact plate 139. The hole 136 in the header 128 is slightly oversize with respect to the diameter of the stem 80 and the annular seal 138 has a relatively, low

coefficient of friction in order that the stem 80 can be freely moved between its low and high temperature positions, as was previously described. Further, the stem 80 slides in engagement with the axial flange 13% of the contact plate 139 during such movement.

In assembly, the free end of the side flange 116 is crimped in a circular manner over the header 128 and contact plate 139. The crimping of the side flange 116 serves to force the header 128 to compress the radial flange 122 of the diaphragm 120 between the radial flange 114 of the housing 108 and the bottom side 130 of the header 128. This compression of the radial flange 122 causes a bead 140 on the diaphragm 120 to sealingly engage the bottom of the circumferential groove 132. The resulting bead 140 and the compression of the radial flange 122 of the diaphragm 120 serves to seal the inner chamber 113 of the housing 108 from the remainder of the switch assembly 10 and also serves to maintain the diaphragm 120 in the above described desired position.

An annular fitting 141 is located in a concentric relationship about the housing 108. The fitting 141 includes an annular side wall 141a which is exteriorly threaded in order that the switch assembly 10 can be threadably received within a complementary threaded opening in a heat source, such as an automotive engine, and defines a central opening 142 therethrough which is generally complementary in shape to the side wall 112 of the housing 108. The upper end of the fitting 141 also includes a radially outwardly extending flange 143 which terminates in an axially extending side flange 143a which in turn defines an open opening complementary in shape to the lower end of the housing means 112. The housing 108 is press fit within the opening 142 of the annular fitting 141, and the radial lip 34 of the housing means 12 is received within the opening defined by the side flange 143a of the fitting 141. Further, the lower end of the housing means 12 is positioned in an abutting relationship with the radial flange 143 of the annular fitting 141 and, thereafter, the side flange 143a of the annular fitting 141 is crimped over the radial lip 34 of the housing means 12 to join the power element 18in the housing means 12.

A thermal sensitive, expansible substance 144, such as a wax mixture which when heated would melt and expand volumetrically approximately percent, is located within the inner chamber 113 of the housing 108 between the diaphragm 120 and the side wall 112. In operation it should be understood that an increase in the temperature of the thermally expansible substance above a first predetermined temperature, as a result of increases in the temperature of the heat source (not shown) to which the housing 108 is exposed, results in a volumetric increase in the thermally expansible substance 144. The volumetric increase in the thermally expansible substance 144 places radially inward forces upon the diaphragm 120 which tends to compress the diaphragm 120. In this respect, that portion of the diaphragm 120 defining the conical end portion 126 of the inner chamber 124 is compressed and pinches or cams the complementary conical end portion 98 of the stem 80 which effects a vertical sliding movement of the stem 80 within the inner chamber 124 of the diaphragm 120. Eventually, the contact carrier 14 is moved sufficiently that the conical end portion 98 of the stem 80 passes from the complementary shaped conical end portion 126 of the inner chamber 124 of the diaphragm 120.' Continued volumetric expansion serves to compress the diaphragm 120 and move the annular side wall 128 which is. immediately adjacent and below the conical end portion 98 of the stem 80 radially inwardly. It should be understood that the radially inward movement of the annular side walls 120a of the diaphragm 120 pinches or cams the conical end portion 98 of the stem 80 and thereby forces the contact carrier 14 to move vertically upward within the inner chamber 28 of the housing means 12 and toward the position shown in dotted lines in FIG. 1. It should also be understood that decreases in the temperatures of the thermally sensitive, expansible substance 144 results in volumetric contraction which in turn tends to decrease the radially inward forces upon the diaphragm and allows the annular side wall 120a to return radially outwardly toward the position shown in FIG. 1. The return of annular side wall 120a toward that position allows the bias of the spring 116 to move the contact carrier 14 vertically downward toward the position shown in solid lines in FIG. 1.

Now referring to FIGS. 3 and 4, the printed circuit means 20 generally comprises a pair of circuit boards and 146. Both the

circuit boards

145 and 146 have a base 148 and 149 of insulating material, such as plastic, which are somewhat elongated and rectangularly shaped. Referring to FIG. 3, the circuit board 145 has three conductors 151-153 printed thereon which are connected with first, second and third circuits of the first electric circuit means (not shown), respectively.

The conductors 151-153 are printed in elongated strips or patterns which extend from the upper end of the base 148 along its length. The conductor 151 is shown as having a long, vertical portion 151a extending downwardly from the upper end of the base 148 and terminating in a horizontal portion l5lb which in turn terminates in a short vertical portion l5lc which extends downwardly toward the lower end of the base 148. The conductor 152 is shown to extend vertically downward from the upper end of the base 148 and to terminate at a position approximately at center of the base 148. Similarly, the conductor 153 is shown to extend vertically downward from the upper end of the base 148 to a position approximately three-fourths of the way from the upper end of the base 148 to the lower end of the base 148. The circuit board 146 is shown as having a conductor 155 printed thereon which is connected to the second electric circuit means (not shown) and having a vertical portion 155a extending vertically downward from the upper end of the base 149 to approximately the center of the base 149 where it terminates in a short horizontal portion l55b which in turn terminates in another vertical downward extending portion 1556.

It is very important to note that the patterns of the conductors 151-153 and 155 herein described and shown in FIGS. 3 and 4 are purely exemplary, and that the scope of the invention should not in any way be limited by those descriptions. The form, shape, and numbers of the printed conductors of the circuit boards 45 and 46 are determined purely by the desired operatelongated strips 68-70 of the terminals 52-54, engage the uppermost portions of the vertical portion 151a of the conductor 15], the conductor 152 and the conductor 153, respectively, to provide electrical continuity therebetween and to retain the circuit board 145 vertically within the channel 160. In this respect, the conductor 151 is electrically connected with the engine cold light (not shown) via the terminal 52, the conductor 152 is electrically connected with the engine hot light (not shown) via the terminal 53 and the conductor 153 is electrically connected with the heater blower (not shown) via the terminal 54. The bent end (not shown) of the spring contact 76 of the terminal 65 engages the uppermost portion of the vertical portion 155a of the conductor 155 to provide electrical continuity therebetween and to retain the circuit board 146 within the channel 161. It should be seen that the conductor 155 is electrically connected with the previously described solenoid valve (not shown) via the terminal 65. Further, the axial movement of the

circuit boards

145 and 146 within the

slots

157 and 158 is prevented by virtue of the abutting relationship between the end of the

circuit boards

145 and 146 and the radial flange 143 of the fitting 141.

Referring to FIGS. 1, 3 and 4, it should be seen that when the contact carrier 14 is in its first position, as shown by the solid lines in FIG. 1, the bent end 94 of the second contact 88 on the contact carrier 14 is engaged with the vertical portion 151C of the conductor 151 and that the bent end 86 of the contact 84 on the contact carrier 14 is engaged with the base 149 of the circuit board 146 at a position immediately below the vertical portion 1550 of the conductor 155. In this respect, the engine hot light, the heater blower, and the solenoid valve (all of which are not shown) are in a deenergized state and the engine cold light (not shown) is energized through a circuit traced from the terminal 52 which is electrically connected with the engine cold light, to the conductor 151, to the contact 88, to the stem 80 of the contact carrier 14, to the contact plate 139, to the housing 108, and to ground.

When the contact carrier 14 is in its second position, as shown by the dotted lines in FIG. 1, the bent end 86 of the contact 84 is engaged with the. vertical portion 1556 of the conductor 165 and the bent end 94 of the contact 88 is engaged with the vertical portion 151C of the conductor 151 while remaining out of engagement with the

conductors

152 and 153. In this respect, the engine hot light and the heater blower (not shown) are in a deenergized state, the engine cold light (not shown) remains energized, and the solenoid valve (not shown) is energized through a circuit traced from the terminal 61 which is connected with the power source (not shown) to the spring 16, to the contact 84, to the conductor 155', to the terminal 65 which is electrically connected with the solenoid valve (not shown) that is in turiigrounded.

When the contact carrier 14 is in its third position, as shown by the phantom lines in FIG. 1, the contact 88 is engaged with the lower end of the conductor 153 and is positioned immediately adjacent the vertical portion 1510 of the conductor 151 but out of engagement therewith. Further, the contact 88 is below the lower end of the conductor 152. Also, the contact 84 remains engaged with the vertical portion 155c of the conductor 155. In this respect, the engine cold light and theengine hot light (not shown) are deenergized, the solenoid valve (not shown) remains in its energized state, and the heater blower (not shown) is energized through a circuit traced from the terminal 54 which is electrically connected with the heater blower, to the conductor 153, to the second contact 88, to the stem 80, to the contact plate 139, to the housing 108, and to ground.

When the contact carrier 14 is in its fourth position, as shown by the dashed lines in FIG. Lthe contact 88 is positioned immediately below the lower end of the conductor 152, adjacent the vertical portion 151a of the conductor 151, and in engagement with the conductor 153. Further, the contact 84 is positioned immediately above the horizontal portion l55b and immediately adjacent the vertical portion a of the conductor 155. In this respect the engine cold light, the engine hot light, and the solenoid valve (all of which are not shown) are in a deenergized state, and the heater blower (not shown) remains in an energized state through the circuit previously traced.

When the contact carrier 14 is in its fifth position, as shown by the dash-dot linesin FIG. jlfthe eontact 88 is engaged with the

conductors

152 and 153 in a position immediately adjacent but out of engagement with the vertical portion 1510 of the conductor 151. Additionally, the contact 84 is positioned irriritecliately adjacent but out of engagement with the vertical portion 155a of the conductor 155. In this respect, the engine cold light and the solenoid valve (not shown) are in a deenergized state, the heater blower remains energized, and the engine hot light (not shown) is energized through a circuit traced from the terminal 53 which is connected electrically with the engine hot light, to the conductor 152 to the second contact 88, to the stem 80, to the contact plate 139, to the housing 108, and to ground.

In operation, the contact carrier 14 is in its first position thus energizing the engine cold light (not shown) when the temperature of the engine coolant (not shown) is equal to a first predetermined value. When the temperature of the engine coolant (not shown) is increased to a second predetermined temperature greater than the first predetermined temperature the contact carrier is moved in a similar manner to that previously described to its second position where the engine cold light (not shown) remains energized and the solenoid valve (not shown) is also energized. It follows that when the temperature of the engine coolant reaches a third predetermined temperature greater than the first and second predetermined temperatures, the resulting volumetric expansion of the thermally expansible substance 144 results in the contact carrier 14 being moved to its third position where the engine cold light (not shown) is deenergized, the solenoid valve (not shown) remains energized, and the heater blower (not shown) is energized. An increase in the temperature of the engine coolant (not shown) to a fourth predetermined temperature serves to position the contact carrier 14 in its fourth position where the engine cold light (not shown) remains deenergized, the solenoid valve (not shown) is deenergized, and the heater blower (not shown) remains energized. The contact carrier 14 reaches its fifth position when the temperature of the engine coolant is increased to a fifth predetermined temperature, and in this respect, the engine hot light (not shown) is energized, the heater blower (not shown) remains energized, and the engine cold light and solenoid valve (not shown) remains deenergized. It should be understood that decreases in the temperature of the engine coolant (not shown) results in volumetric contraction of the thermally expansible means 144 which in turn allows the contact carrier 14 to move vertically downward within the inner chamber 28, and that the resulting effects will be the reverse of that described above.

One advantage of the present invention is that the operation of different devices can be varied or different functions can be controlled in response to temperature changes in a heat source by merely substituting different circuit boards with different printed circuits thereon.

The foregoing disclosure relates to only one embodiment of the invention which may be modified within the scope of the appended claims.

What is claimed is:

1. A thermoelectrical switch comprising: a housing means defining an inner chamber and having terminal means adapted to be connected with electric circuit means; printed circuit board means disposed within said inner chamber of said housing means and electrically connected with said terminal means of said housing means; a piston-like contact carrier supported within said housing means adjacent said printed circuit board means for linear movement between different circuit energized and circuit deenergized positions, said contact carrier having contact means affixed thereto which is disposed to engage said printed circuit board means when said contact carrier is moved to its circuit energized position and disposed to disengage said printed circuit board means when said contact carrier is moved to its circuit deenergized position; spring means for biasing said contact carrier in one direction within said housing means; thermally expansible means for effecting movement of said contact carrier within said housing means against the bias of said spring means when its temperature is increasing from a predetermined temperature, said thermally expansible means allowing the bias of said spring means to effect movement of said contact carrier in said one direction within said housing means when its temperature means is decreasing toward said predetermined temperature whereby said contact carrier is moved between its different circuit energized and circuit deenergized positions.

2. A thermoelectrical switch comprising: housing means defining an elongated inner chamber; first and second terminal means carried by said housing means and adapted to be connected within first electric circuit means; third terminal means carried by said housing means and adapted to be connected with second electric circuit means; a piston-like contact carrier supported within said housing means for linear movement within said .inner chamber between different first and second circuit energized and deenergized positions, said contact carrier having a first contact affixed thereto and also having a grounded second contact affixed thereto; spring means extending between said first terminal means of said housing means and said first contact of said contact carrier for providing electrical continuity therebetween and for biasing said contact carrier in one direction within said inner chamber; thermally expansible means expanding when its temperature is increasing from a predetermined temperature for effecting movement of said contact carrier between different ones of its positions in opposition to the bias of said spring means, said thermally expansible material contracting when its temperature is decreasing toward said predetermined temperature and allowing the bias of said spring means to effect movement of said contact carrier in said one direction; first and second circuit boards disposed within said inner chamber of said housing means adjacent the path of said contact carrier and having first and second conductor means, respectively, printed in elongated and continuous strips extending along the path of said contact carrier, said first conductor means being connected with said second terminal means and said second conductor means being connected with said third terminal means, said first conductor means having portions disposed for said first contact on said contact carrier to slide into en gagement therewith when said contact carrier is moved to its first circuit energized positions to energize said first electric circuit means and having portions thereof disposed for said first contact of said contact carrier to slide out of engagement therewith when said contact carrier is moved to its first circuit deenergized positions to deenergize said first electric circuit means, said second conductor means having portions disposed for said second contact on said contact carrier to slide into engagement therewith upon movement of said contact carrier to its second circuit energized positions to energize said second electric circuit means and having portions thereof disposed for said second contact of said contact carrier to slide out of engagement therewith when said contact carrier is moved to its second circuit deenergized positions to deenergize said second electric circuit means.

3. A thermoelectrical switch for controlling the energization of first, second, third and fourth electric circuit means comprising: housing means defining an elongated, non-circular inner chamber; a first terminal means carried by said housing means and adapted to be connected with the power source of the first electric circuit means, second terminal means carried by said housing means and adapted to be connected with an electrically operated device of said first electric circuit means, third and fourth and fifth terminal means carried by said housing means and adapted to be connected with the second and third and fourth electric circuit means, respectively; a piston or a contact carrier complementary in shape with said inner chamber of said housing means and supported therein for linear movement between different positions, said contact carrier having a first contact and a grounded second contact fixed thereto; spring means extending between said first terminal means of said housing means and said first contact of said contact carrier for providing electrical continuity therebetween and for biasing said contact carrier in one direction within said one inner chamber; a power element having a thermally expansible material isolated from said inner chamber of said housing means by deflectable diaphragm which supports said piston member, said thermally expansible material expanding when its temperature is increasing from a predetermined temperature for effecting movement of said contact carrier between different ones of its positions in opposition to the bias of said spring means, said thermally expansible material contracting when its temperature is decreasing toward said predetermined temperature and allowing the bias of said spring means to effect movement of said contact carrier between different ones of its positions in said one direction; first and second circuit boards disposed within recesses in said housing means and adjacent the path of movement of said contact carrier, said first circuit board having a first elongated and continuous conductor strip extending along the path of said contact carrier, said first conductor strip being connected with said second terminal means, said second circuit board having second and third and fourth elongated and continuous conductor strips extending along the path of said contact carrier, said second and third and fourth conductor strips being connected with said third and fourth and fifth terminal means respectively, said first conductor strip having certain portions thereof disposed for said first contact on said contact carrier to slide into engagement and out of engagement therewith when said contact carrier is moved to different ones of its positions to energize and deenergize, respectively, said first electric circuit means, said second and third and fourth conductor strips also having certain different portions thereof disposed for said second contact on said contact carrier to slide into engagement and out of engagement therewith upon movement of said contact carrier to different ones of its positions to energize and deenergize, respectively, said second and third and fourth electric circuit means.

4. A thermoelectrical switch for controlling the operation of a spark advance and retard solenoid switch, an engine cold light, an engine hot light, and a heater blower in an automotive vehicle, comprising: housing means defining an elongated, non-circular inner chamber; first terminal means carried by said housing means adjacent one end of said inner chamber and adapted to be connected with a power source, second terminal means recessed within said housing means adjacent said one end of saidinner chamber and adapted to be connected with the solenoid valve, third and fourth and fifth terminal means recessed within said housing means adjacent said one end of said inner chamber and adapted to be connected with an engine cold light electric circuit means and an engine hot light electric circuit means and a heater blower electric circuit means, respectively; a piston or a contact carrier shaped complementary to said inner chamber and supported therein for linear movement between different positions, said contact carrier having a first contact and a groundedsecond contact fixed thereto; spring means extending between said first terminal means of said housing means and said first contact of said contact carrier for providing electrical continuity therebetween and for biasing said contact carrier in one direction within said inner chamber; a power element adjacent the other end of said inner chamber of said housing means and having a thermally expansible material isolated from said inner chamber by a deflectable diaphragm which supports the contact carrier, said thermally expansible material expanding when its temperature is increasing from a predetermined temperature for effecting movement of said contact carrier between different ones of its positions in opposition to the bias of said spring means, said thermally expansible material contracting when the temperature is decreasing toward said predetermined temperature and allowing the bias of said spring means to effect movement of tact carrier, said first circuit board having a first elongated and continuous conductor strip extending along the length of said contact carrier and being connected with said second terminal means, said second circuit board having second and third and fourth elongated and continuous strips extending along the length of said contact carrier and being connected with said third and fourth and fifth terminal means respectively; said first conductor strip having portions disposed for said first contact on said contact carrier to slide into engagement therewith when said contact carrier is moved to a first and second positions to energize the solenoid-switch electric circuit means, said second conductor strip having portions thereof disposed for said second contact of said contact carrier to slide into engagement therewith when said contact carrier is moved to its first position and a third position to energize the engine cold light electric circuit means, said third conductor strip having portions thereof disposed for said second contact on said contact carrier to slide into engagement therewith when said contact carrier is moved to a fourth position to energize said engine hot light electric circuit means, and said fourth conductor strip having portions thereof disposed for said second contact on said contact carrier to slide into engagement therewith when said contact carrier is moved to its second position and a fifth p osi--

Claims

2. A thermoelectrical switch comprising: housing means defining an elongated inner chamber; first and second terminal means carried by said housing means and adapted to be connected within first electric circuit means; third terminal means carried by said housing means and adapted to be connected with second electric circuit means; a piston-like contact carrier supported within said housing means for linear movement within said inner chamber between different first and second circuit energized and deenergized positions, said contact carrier having a first contact affixed thereto and also having a grounded second contact affixed thereto; spring means extending between said first terminal means of said housing means and said first contact of said contact carrier for providing electrical continuity therebetween and for biasing said contact carrier in one direction within said inner chamber; thermally expansible means expanding when its temperature is increasing from a predetermined temperature for effecting movement of said contact carrier between different ones of its positions in opposition to the bias of said spring means, said thermally expansible material contracting when its temperature is decreasing toward said predetermined temperature and allowing the bias of said spring means to effect movement of said contact carrier in said one direction; first and second circuit boards disposed within said inner chamber of said housing means adjacent the path of said contact carrier and having first and second conductor means, respectively, printed in elongated and continuous strips extending along the path of said contact carrier, said first conductor means being connected with said second terminal means and said second conductor means being connected with said third terminal means, said first conductor means having portions disposed for said first contact on said contact carrier to slide into engagement therewith when said contact carrier is moved to its first circuit energized positions to energize said first electric circuit means and having portions thereof disposed for said first contact of said contact carrier to slide out of engagement therewith when said contact carrier is moved to its first circuit deenergized positions to deenergize said first electric circuit means, said second conductor means having portions disposed for said second contact on said contact carrier to slide into engagement therewith upon movement of said contact carrier to its second circuit energized positions to energize said second electric circuit means and having portions thereof disposed for said second contact of said contact carrier to sLide out of engagement therewith when said contact carrier is moved to its second circuit deenergized positions to deenergize said second electric circuit means.

4. A thermoelectrical switch for controlling the operation of a spark advance and retard solenoid switch, an engine cold light, an engine hot light, and a heater blower in an automotive vehicle, comprising: housing means defining an elongated, non-circular inner chamber; first terminal means carried by said housing means adjacent one end of said inner chamber and adapted to be connected with a power source, second terminal means recessed within said housing means adjacent said one end of said inner chamber and adapted to be connected with the solenoid valve, third and fourth and fifth terminal means recessed within said housing means adjacent said one end of said inneR chamber and adapted to be connected with an engine cold light electric circuit means and an engine hot light electric circuit means and a heater blower electric circuit means, respectively; a piston or a contact carrier shaped complementary to said inner chamber and supported therein for linear movement between different positions, said contact carrier having a first contact and a grounded second contact fixed thereto; spring means extending between said first terminal means of said housing means and said first contact of said contact carrier for providing electrical continuity therebetween and for biasing said contact carrier in one direction within said inner chamber; a power element adjacent the other end of said inner chamber of said housing means and having a thermally expansible material isolated from said inner chamber by a deflectable diaphragm which supports the contact carrier, said thermally expansible material expanding when its temperature is increasing from a predetermined temperature for effecting movement of said contact carrier between different ones of its positions in opposition to the bias of said spring means, said thermally expansible material contracting when the temperature is decreasing toward said predetermined temperature and allowing the bias of said spring means to effect movement of said contact carrier between different ones of its positions in said one direction; first and second circuit boards disposed within recesses within said housing means and adjacent the path of movement of said contact carrier, said first circuit board having a first elongated and continuous conductor strip extending along the length of said contact carrier and being connected with said second terminal means, said second circuit board having second and third and fourth elongated and continuous strips extending along the length of said contact carrier and being connected with said third and fourth and fifth terminal means respectively; said first conductor strip having portions disposed for said first contact on said contact carrier to slide into engagement therewith when said contact carrier is moved to a first and second positions to energize the solenoid switch electric circuit means, said second conductor strip having portions thereof disposed for said second contact of said contact carrier to slide into engagement therewith when said contact carrier is moved to its first position and a third position to energize the engine cold light electric circuit means, said third conductor strip having portions thereof disposed for said second contact on said contact carrier to slide into engagement therewith when said contact carrier is moved to a fourth position to energize said engine hot light electric circuit means, and said fourth conductor strip having portions thereof disposed for said second contact on said contact carrier to slide into engagement therewith when said contact carrier is moved to its second position and a fifth position to energize said heater blower electric circuit means.