Temperature switch
09601293 ยท 2017-03-21
Assignee
Inventors
Cpc classification
H01H2037/5481
ELECTRICITY
H01H2037/5463
ELECTRICITY
International classification
Abstract
A base member includes a terminal fixing part for blocking an entire surface of an opening part of a housing at a position further inner than an opening end part of the housing when the base member is inserted in the housing. A first electrode part formed by a tip part of two bent stages that are composed of a horizontal part, a vertical part, and a horizontal part and configured by bending a portion of a part of the fixed side fixed a conductive member, which is continuous with a first external connection terminal, in a direction perpendicular to a continuous direction.
Claims
1. A temperature switch having a housing that is sealed by a sealing member and made of an insulative resin, a base member that is accommodated within the housing and made of an insulative resin, and an electric current path that is molded and integrated with the base member as one body and held by the base member, the temperature switch opening an electric contact of an energized circuit to an electric appliance when a temperature of the electric appliance exceeds a specified temperature, wherein: the base member comprises a terminal fixing part for blocking an entire surface of an opening part of the housing at a position further inner than an opening end part of the housing when the base member is inserted in the housing; the sealing member is made of a liquid curable resin, and seals the opening of the housing at the position further inner than the opening end part of the housing by covering an entire surface of the terminal fixing part of the base member; and the current path comprises a first external connection terminal, a fixed side fixed conductive member continuous with the first external connection terminal as one body, a first electrode part formed by a tip part of two bent stages that are composed of a horizontal part, a vertical part, and a horizontal part and configured by bending a portion of a part of the fixed side fixed conductive member, which is continuous with the first external connection terminal, in a direction perpendicular to a continuous direction, a fixed contact attached to the first electrode part, a movable contact arranged to face the fixed contact and to make contact with the fixed contact at a specified temperature or lower, a movable plate for holding a thermal reaction element, a warpage direction of which is inverted when the temperature switch exceeds the specified temperature, on a side opposite to a side to which the movable contact is attached, an intermediate fixing plate, provided with a tongue piece on one side at an end opposite to a holding part, for fixing and holding an end opposite to an end to which the movable contact of the movable plate is attached, a second electrode part connected to the tongue piece of the intermediate fixing plate, a movable side fixed conductive member continuous with the second electrode part as one body, and a second external connection terminal formed by an extension part of the movable side fixed conductive member, wherein the base member is provided with extension parts that extend from both of ends of an inner surface of the terminal fixing part toward the inside of the housing, and the extension parts have a length double or more of a thickness of the terminal fixing part in a depth direction of the housing, and a width that does not exceed the thickness, and a portion or a whole of a top surface or a bottom surface makes contact with the interior surface of the housing.
2. The temperature switch according to claim 1, wherein the sealing member forms a sealed surface vertical to an interior surface of the housing, and the first external connection terminal and the second external connection terminal respectively extend externally from the sealing member by penetrating into the sealing member vertically to the sealed surface of the sealing member from the interior surface of the housing at a position where a clearance corresponding to a thickness of an insulation tube is left, a cross-section, perpendicular to an axis, of the first external connection terminal and the second external connection terminal is formed to take the shape of V or U from a portion nearly immediately after the terminal extends externally from the sealing member to a tip part, an extremity of the first external connection terminal and the second external connection terminal is formed as a lead wire swaged terminal, and one or more cutout parts are formed on a side of a portion between the extremity and the sealing member.
3. A temperature switch having a housing that is sealed by a sealing member and made of an insulative resin, a base member that is accommodated within the housing and made of an insulative resin, and an electric current path that is molded and integrated with the base member as one body and held by the base member, the temperature switch opening an electric contact of an energized circuit to an electric appliance when a temperature of the electric appliance exceeds a specified temperature, wherein: the base member comprises a terminal fixing part for blocking an entire surface of an opening part of the housing at a position further inner than an opening end part of the housing when the base member is inserted in the housing; the sealing member is made of a liquid curable resin, and seals the opening of the housing at the position further inner than the opening end part of the housing by covering an entire surface of the terminal fixing part of the base member; and the current path comprises a first external connection terminal, a fixed side fixed conductive member continuous with the first external connection terminal as one body, a first electrode part formed by a tip part of two bent stages that are composed of a horizontal part, a vertical part, and a horizontal part and configured by bending a portion of a part of the fixed side fixed conductive member, which is continuous with the first external connection terminal, in a direction perpendicular to a continuous direction, a fixed contact attached to the first electrode part, a movable contact arranged to face the fixed contact and to make contact with the fixed contact at a specified temperature or lower, a movable plate for holding a thermal reaction element, a warpage direction of which is inverted when the temperature switch exceeds the specified temperature, on a side opposite to a side to which the movable contact is attached, an intermediate fixing plate, provided with a tongue piece on one side at an end opposite to a holding part, for fixing and holding an end opposite to an end to which the movable contact of the movable plate is attached, a second electrode part connected to the tongue piece of the intermediate fixing plate, a movable side fixed conductive member continuous with the second electrode part as one body, and a second external connection terminal formed by an extension part of the movable side fixed conductive member, wherein the base member is provided with, in a central portion of an outer surface of the terminal fixing part, a protrusion part having a length that is equal to or longer than the thickness of the terminal fixing part in the depth direction of the housing and a width that does not exceed the thickness, is externally exposed by penetrating into the sealing member, and has the externally exposed tip part that is aligned on a same vertical plane as an opening part end surface of the housing, and the protrusion part is provided with a cutout groove corresponding to a sealing thickness of the sealing member at a top and a bottom of a root of the terminal fixing part.
4. The temperature switch according to claim 2, wherein the first external connection terminal and the second external connection terminal are respectively connected by swaging a lead wire, and attached with an insulation tube having a length needed for insulation inclusive of a connection portion with the lead wire, the insulation tube is inserted until the insulation tube reaches the sealed surface of the sealing member, and is fixed to an insulation portion by being contracted and cured with heating, and the temperature switch is incorporated in the electric appliance in a state where complete insulation with no exposed portions in a conductive portion is maintained.
5. The temperature switch according to claim 3, wherein the sealing member forms a sealed surface vertical to an interior surface of the housing, and the first external connection terminal and the second external connection terminal respectively extend externally from the sealing member by penetrating into the sealing member vertically to the sealed surface of the sealing member from the interior surface of the housing at a position where a clearance corresponding to a thickness of an insulation tube is left, a cross-section, perpendicular to an axis, of the first external connection terminal and the second external connection terminal is formed to take the shape of V or U from a portion nearly immediately after the terminal extends externally from the sealing member to a tip part, an extremity of the first external connection terminal and the second external connection terminal is formed as a lead wire swaged terminal, and one or more cutout parts are formed on a side of a portion between the extremity and the sealing member.
6. The temperature switch according to claim 5, wherein the first external connection terminal and the second external connection terminal are respectively connected by swaging a lead wire, and attached with an insulation tube having a length needed for insulation inclusive of a connection portion with the lead wire, the insulation tube is inserted until the insulation tube reaches the sealed surface of the sealing member, and is fixed to an insulation portion by being contracted and cured with heating, and the temperature switch is incorporated in the electric appliance in a state where complete insulation with no exposed portions in a conductive portion is maintained.
7. The temperature switch according to claim 1, wherein a portion of the first external connection terminal, which is arranged within the housing, the fixed side fixed conductive member, a portion of the second external connection terminal which is arranged within the housing, the movable side fixed conductive member, and the base member are integrated into one body with insert molding, and the first external connection terminal and the second external connection terminal are respectively formed by being bent into two stages composed of a horizontal part continuous with a tip part, a vertical part, and a horizontal part in an axis direction, an inner side of the horizontal part continuous with the tip part is formed as a flat plate from a position before the horizontal part externally penetrates into the sealing member in a state where the horizontal part penetrates into the sealing member and is drawn into the housing.
8. The temperature switch according to claim 7, wherein the vertical part, succeeding the horizontal part continuous with the tip part, of the portion formed by being bent into the two stages comprises a protrusion part that extends further upper than the horizontal part on both sides, and the portion formed by being bent into the two stages, and the protrusion part are buried in the terminal fixing part of the base member.
9. The temperature switch according to claim 3, wherein a portion of the first external connection terminal, which is arranged within the housing, the fixed side fixed conductive member, a portion of the second external connection terminal, which is arranged within the housing, the movable side fixed conductive member, and the base member are integrated into one body with insert molding, and the first external connection terminal and the second external connection terminal are respectively formed by being bent into two stages composed of a horizontal part continuous with a tip part, a vertical part, and a horizontal part in an axis direction, an inner side of the horizontal part continuous with the tip part is formed as a flat plate from a position before the horizontal part externally penetrates into the sealing member in a state where the horizontal part penetrates into the sealing member and is drawn into the housing.
10. The temperature switch according to claim 9, wherein the vertical part, succeeding the horizontal part continuous with the tip part, of the portion formed by being bent into the two stages comprises a protrusion part that extends further upper than the horizontal part on both sides, and the portion formed by being bent into the two stages, and the protrusion part are buried in the terminal fixing part of the base member.
Description
BRIEF DESCRIPTION OF DRAWINGS
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BEST MODE OF CARRYING OUT THE INVENTION
(9) An embodiment according to the present invention is described in detail below with reference to the drawings.
First Embodiment
(10) As illustrated in
(11) Inside the housing 2 made of the insulative resin, a base member 4 made of an insulative resin, and components that are integrated with the base member 4 as one body with insert molding and are held by the base member 4 are accommodated.
(12) The base member 4 has a terminal fixing part 4a that forms a surface vertical to an interior surface of the housing 2 at a position 2b further inner than an opening end part 2a of the housing 2 when the base member 4 is inserted into the housing 2 and blocks the entire opening of the housing 2.
(13) The sealing member 3 is made of a liquid curable resin, is cured by being injected into the vertical surface of the base member 4 to be nearly evenly thick, and seals the opening of the housing 2 vertically to the interior surface of the housing 2 at the position 2b further inner than the opening end part 2a of the housing 2 by covering the entire vertical surface of the terminal fixing part 4a of the base member 4.
(14) As components that are integrated with the base member 4 as one body and held by the base member 4, a first external connection terminal 5 and a second external connection terminal 6 are provided. A current path is formed between the first external connection terminal 5 and the second external connection terminal 6 as illustrated in a block diagram of
(15) As illustrated in
(16) As illustrated in
(17) Additionally, an extremity of a portion of the first external connection terminal 5, which externally extends from the sealing member 3, is formed as a lead wire swaged terminal 17.
(18) Furthermore, a cross-section, perpendicular to an axis, of the first external connection terminal 5 is formed to take the shape of V or U from a position 5d nearly immediately before the terminal protrudes externally from the sealing member 3 to the tip part (a root of the lead wire swaged terminal 17). In
(19) Still further, one or more cutout parts 18 are formed on a side of a portion of the first external connection terminal 5 between the extremity and the sealing member 3.
(20) Since the cutout parts 18 are formed, they absorb external forces even if the forces that bend the tip part of the terminal, namely, the lead wire swaged terminal 17 in right and left directions are applied. This eliminates an ill effect of distorting an internal structure of the terminal.
(21) Additionally, the portion of the first external connection terminal 5, which is arranged within the housing 2, is formed by being bent into two stages composed of a horizontal part 5a continuous with the tip, a vertical part 5b, and a horizontal part 5c in an axis direction of the terminal as illustrated in
(22) When viewed from a different angle, the horizontal part 5a continuous with the tip is drawn into the housing 2 by externally penetrating into the sealing member 3. Moreover, the inner side from the position 5d immediately before the horizontal part 5a externally penetrates into the housing 2 is formed as a flat plate.
(23) As described above, the inner side from the position 5d immediately before the first external connection terminal 5 externally penetrates into the sealing member 3 is formed as the flat plate. Therefore, even if external forces that bend the tip part of the terminal, namely, the lead wire swaged terminal 17 upward or downward are applied, the portion formed as the flat plate absorbs the external forces. This eliminates the fear of distorting the internal structure of the terminal.
(24) The terminal fixing part 4a of the base member 4, which is present on the side further inner than the sealing member 3 and makes close contact with the sealing member 3, is provided with internal extension parts 22 (22a, 22b) that extend from both of ends of the terminal fixing part 4a toward the inner side of the housing 2.
(25) The two internal extension parts 22 are formed to avoid the contacts and a mechanical part of the movable plate 13 and to extend along an interior wall of the housing on both of sides of the contacts and the mechanical part of the movable plate 13 within the housing 2.
(26) The entire surface of the top of the internal extension parts 22 may be configured to make contact with an interior surface of the top of the housing 2, or a portion including the tip of the extension part may be configured to make contact with the interior surface of the top of the housing 2 and create a clearance in an intermediate portion from the root of the internal extension part 22 to the tip.
(27) In either configuration, the internal extension parts 22 are present to implement the function of preventing the terminal fixing part 4a from being displaced so that the terminal fixing part 4a falls in neither the internal direction nor the external direction.
(28) In addition to the internal extension parts 22, a structure for strengthening the terminal fixing part 4a may be provided outside the base member 4. Namely, an external extension part 23 is formed to extend up to the opening end part of the housing 2 by penetrating into the sealing member 3 from the center of the exterior surface of the terminal fixing part 4a.
(29) It is preferable that top and bottom surfaces of the external extension part 23 and those of the terminal fixing part 4a are nearly on the same plane. Moreover, the top and the bottom surfaces of the external extension part 23 are configured to always make contact with the interior surfaces of the top and the bottom of the housing 2, or to make contact with the interior surfaces of the top and the bottom of the housing 2 when an external force is applied to the first external connection terminal or the second external connection terminal.
(30) Thus, the function of preventing the terminal fixing part 4a from being displaced so that the terminal fixing part 4a falls in neither the internal direction nor the external direction is strengthened in addition to the function of the internal extension parts 22. Note that cutout parts 23a are provided at the top and the bottom of the root part from which the external extension part 23 protrudes from the terminal fixing part 4a.
(31) To seal the sealed surface, the sealing member 3 needs to be filled at the entire edge of the sealed surface along the sealed surface. If the external extension part 23 protrudes from the terminal fixing part 4a as it is, the sealing member 3 becomes discontinuous at the root of the external extension part 23, so that the sealed surface is not completely sealed.
(32) However, by providing the above described cutout parts 23a, the sealing member 3 goes into the cutout parts 23a when the liquid sealing member 3 is injected into the sealed surface of the terminal fixing part 4a, so that the sealing member 3 becomes continuous at the entire edge part of the sealed surface.
(33) As a result, the main body of the switch that is integrated with the base member 4 as one body can be completely sealed within the housing 2 when the liquid sealing member 3 is cured after heated.
(34) Note that the external extension part 23 has a function of preventing exposed portions of both of the terminal parts from making contact with each other when a lead wire is swaged to the lead wire swaged terminal 17 of the first external connection terminal 5 and the second external connection terminal 6 and when the first external connection terminal 5 and the second external connection terminal 6 are covered with an insulation tube in addition to the function of securely fixing the position of the terminal fixing part 4a.
(35) Here, a protrusion part 5e that extends further upper than the horizontal part 5a is formed on both of sides of the vertical part 5b in the portion bent into the two stages composed of the above described horizontal part 5a, vertical part 5b, and horizontal part 5c of the first external connection terminal 5 as illustrated in
(36) Additionally, the portion bent into the two stages composed of the horizontal part 5a, the vertical part 5b, and the horizontal part 5c, and the protrusion part 5e are buried in the terminal fixing part 4a of the base member 4.
(37) As described above, the portion where the two stages composed of the horizontal part 5a, the vertical part 5b, and the horizontal part 5c, and the protrusion part 5e of the first external connection terminal 5 are formed is held by the terminal fixing part 4a of the base member 4 by being buried as one integrated body.
(38) Furthermore, the position of the terminal fixing part 4a of the base member 4 is securely fixed to the housing 2 by the two internal extension parts 22a, 22b, and the external extension part 23 at the center as described above.
(39) Accordingly, external forces are impeded by the terminal fixing part 4a even if an externally pulling or pressing force in the axis direction of the terminal is applied to the lead wire swaged terminal 17 at the tip part of the first external connection terminal 5, thereby preventing the internal configuration from being distorted.
(40) Also the shape and the placement of the second external connection terminal 6 are similar to those of the first external connection terminal 5 although the above described shape and placement of the first external connection terminal 5 are not viewed in the second external connection terminal 6 illustrated in
(41) The horizontal part 5c of the first external connection terminal 5, which extends toward the innermost part (the left of
(42) A portion of the fixed side fixed conductive member illustrated in
(43) The fixed side fixed conductive member 9 that goes into the far side of the depth direction of the paper sheet in
(44) A portion of the fixed side fixed conductive member 9, which is continuous with the first external connection terminal 5, namely, the horizontal part 9b illustrated in
(45) Additionally, a first electrode part (9a) is formed by the horizontal part 9a, which is the tip part of the two bent stages, as illustrated in
(46) As described above, the fixed contact 11 is attached to the tip part of the two bent stages formed in the direction perpendicular to the axis of the terminal in the portion of the fixed side fixed conductive member 9, which is continuous with the first external connection terminal 5.
(47) Accordingly, even if external forces are applied from the lead wire swaged terminal 17 of the first external connection terminal 5, the forces in the upper, the lower, the right, and the left directions are absorbed by flattening the terminal or forming the cutouts as described above. Therefore, a direction where a remaining external force is applied is only the axis direction of the terminal.
(48) It is difficult for the external force in the axis direction of the terminal to propagate to the first electrode part 9a (horizontal part 9a) at the tip part of the two bent stages formed in the direction perpendicular to the axis of the terminal. Namely, it is no exaggeration to say that there is no possibility of distorting the first electrode part 9a, to which the fixed contact 11 is attached, by external forces propagated from the lead wire swaged terminal 17.
(49) The movable contact 12 is arranged to face the fixed contact 11 attached to the first electrode part 9a.
(50) The movable contact 12 is attached to one end (the right end of
(51) Additionally, the movable plate 13 holds a bimetallic element 19 as a thermal reaction element on a side opposite to the side to which the movable contact 12 is attached. The movable plate 13 is provided with a long hole 21 formed by cutting out a central portion in a long direction as illustrated in
(52) Furthermore, the movable plate 13a is provided with peg parts 13a at both of ends in a short direction on the side opposite to the side to which the movable contact 12 is attached, and also provided with hook parts 13b at both of ends of the long hole 21 in the long direction as illustrated in
(53) Both of the ends of the bimetallic element 19 in the long direction are loosely engaged with the hook parts 13b of the movable plate 13b, and the positions of both of the ends of the bimetallic element 19 in the short direction are regulated by the peg parts 13a of the movable plate 13, so that the bimetalic element 19 is held by the movable plate 13.
(54) The end opposite to that to which the movable contact 12 of the movable plate 13 is attached is fixed to and held by a rear end (the end in the inner direction of the housing 2) at the position of the innermost portion (the left end part of
(55) Additionally, the intermediate fixing plate 14 is provided with a tongue piece 14a on one side of the end (the right end part of
(56) Similarly to the first external connection terminal 5, the second external connection terminal 6 is formed by being bent into two stages composed of a horizontal part continuous with the tip of the terminal, a vertical part, and a horizontal part in the axis direction of the terminal as stated earlier. The horizontal part cited last forms the aforementioned second electrode part 15a.
(57) Namely, the second external connection terminal 6 is connected to the movable contact 12 via the portion formed by being bent into the two stages, the second electrode part 15a, the tongue piece 14a, the intermediate fixing plate 14, and the movable plate 13. The above described configuration forms the current circuit illustrated in
(58) In the temperature switch 1 including the current circuit illustrated in
(59) Additionally, an insulation tube 25 having a length that is needed for insulation inclusive of a connection portion with the lead wire 24 is attached to each of the first external connection terminal 5 and the second external connection terminal 6 as illustrated in
(60) Between the interior surface of the housing 2 from the opening end part to the sealed surface and the terminal part that externally extends from the sealed surface, the clearance 16 corresponding to the thickness of the insulation tube 25 is created as described above.
(61) As a result, by inserting the insulation tubes 25 until they reach the sealed surface of the sealing member 3, a completely insulated state with no exposed portions in the conductive part can be secured. The insulation tubes 25 are contracted and cured by being heated, and fixed to the insulated portion.
(62) The temperature switch 1 according to this embodiment is incorporated in an electric appliance by being connected in series with an energized circuit of the electric appliance 24 by the lead wires after the lead wires 24 are swaged and connected to the above described first and second external connection terminals 5 and 6 and the insulation tubes 25 are heated and cured.
(63) A warpage direction of the bimetalic element 19 of the temperature switch 1 is inverted when a temperature of the electric appliance exceeds a specified temperature, so that the end to which the movable contact 12 of the movable plate 13 is attached is lifted to release the movable contact 12 from the contact with the fixed contact 11. Namely, the bimetalic element 19 interrupts a current of an energized circuit by opening the electric contact of the energized circuit of the electric appliance.
(64) As described above, with the temperature switch 1 according to this embodiment, a structure including the entire switch mechanisms part within an insulative resin housing similar to conventional temperature switches can be implemented, and moreover, the insulative structure of a size that is not larger than the main body even after the lead wires are connected to the terminals can be formed.
(65) Additionally, in the case of such a small-sized structure, the strengths of terminals pose a technical challenge. However, a terminal extension part parallel to the sealed surface is provided by forming a vertical part of the two bent stages within the resin of the terminal fixing part, whereby the strengths of the terminals can be secured.
(66) Furthermore, the extension parts having a shape that makes contact with the inner surfaces of the top and the bottom of the housing are provided inside and outside the terminal fixing part. As a result, the strength of fixing the terminal fixing part itself can be secured.
(67) Still further, the portions having changed shapes such as the changed thickness, the cutout parts on the sides, and the like of the terminal shape are provided outside the sealed surface. Therefore, if external forces are applied to the terminals, a stress concentrates on a portion having a corresponding shape, which is then deformed, thereby preventing the terminal fixing part from being destroyed by eternal forces applied to the terminals.
INDUSTRIAL APPLICABILITY
(68) The present invention is applicable to a temperature switch, incorporated in an electric appliance such as a motor or the like, for interrupting an electric current of the electric appliance by operating when the electric appliance is overheated or an overcurrent occurs.
EXPLANATION OF CODES
(69) 1 temperature switch
(70) 2 housing
(71) 2a opening end part
(72) 2b inner position
(73) 3 sealing member
(74) 4 base member
(75) 4a terminal fixing part
(76) 5 first external connection terminal
(77) 5a horizontal part
(78) 5b vertical part
(79) 5c horizontal part
(80) 5d position before penetration
(81) 5e protrusion part
(82) 6 second external connection terminal
(83) 9 fixed side fixed conductive member
(84) 9a horizontal part (first electrode part)
(85) 9b horizontal part
(86) 9c vertical part
(87) 11 fixed contact
(88) 12 movable contact
(89) 13 movable plate
(90) 13a peg part
(91) 13b hook part
(92) 14 intermediate fixing plate
(93) 14a tongue piece
(94) 15 movable side fixed conductive member
(95) 15a second electrode part
(96) 16 clearance
(97) 17 lead wire swaged terminal
(98) 18 cutout part
(99) 19 bimetalic element
(100) 21 long hole
(101) 22 (22a,22b) internal extension parts
(102) 23 external extension part
(103) 23a cutout part
(104) 24 lead wire
(105) 25 insulation tube