The present invention is related to a temperature switch that opens and closes an electric circuit and to a temperature-switch insulation case used for this type of temperature switch.
Temperature switches have conventionally been known in which the insulation case is filled with a filling material such as a hardening resin so as to mechanically hold a lead wire that is connected to a terminal unit accommodated in the insulation case (see Patent Document 1 for example).
Temperature switches are also known in which the upper and lower insulation-case members are fit into each other although they just sandwich a plate-like terminal instead of holding a lead wire (see Patent Document 2 for example).
Incidentally, the conventional filling-material filling process has two purposes. One is insulation, and the other is the reinforcement of the portion at which the lead wire and the terminal are connected. The insulation is set depending upon the physical distance between the internal live part and the external environment, and requires a dimension that will not cause a problem even when the boundary surface between the lead wire and the filling material peels. For the reinforcement, a hardening resin is advantageous in protecting the above internal connection portion from an external force because the internal connection portion uses a core wire (lead wire).
Also, the covering member of a lead wire is required to be able to respond to bending, and is made of a resin that is relatively flexible. Meanwhile, a filling material used for the above filling is made of a resin that is in a liquid state during the filling and hardens in response to a chemical reaction. This may lead to a problem on the boundary surface between the covering member of a lead wire, which is relatively soft, and a filling material that is relatively hard. For example, there is a problem in which strongly bending a lead wire makes an end portion of the filling material damage the covering member of the lead wire.
Also, the covering member of a lead wire and a filling material tend to fail to be adhered to each other with a high strength, often leading to a situation in which strongly bending the lead wire causes the covering member of the lead wire and the filling material to peel from each other on the boundary surface. This also leads to a problem in which the way of providing a lead wire has to be limited such as for example limiting the range within which the lead wire can bend in order to prevent the peeling.
Further, a filling material is in a liquid state during the filling, leading to problems in which the filling operations require expertise, the hardening of the filling material requires a thermal treatment, and stains are made by a spilt filling material. Note that a filling material being in a liquid state during the filling results in elevation of the center portion of an end portion because of the surface tension, damaging the covering member of the lead wire more often. Further, when the hardening of the filling material requires a heat treatment, the insulation case will also be limited for its heat resistance.
It is an object of the present invention to provide a temperature switch and a temperature-switch insulation case that can prevent damage to the covering member of a lead wire and can surely hold the lead wire, through a simple assembly operation.
According to an aspect, a temperature switch includes a temperature detection unit configured to detect a temperature so as to move a movable contact to a position that is in contact with a fixed contact and to a position that is separated from the fixed contact, a first lead wire that is connected to the fixed contact and that includes a covering member, a second lead wire that is connected to the movable contact and that includes a covering member, and a first-insulation-case member and a second-insulation-case member each of which includes a first-lead-wire concave portion and a second-lead-wire concave portion, and which are fit into each other so as to form an accommodation space that accommodates the temperature detection unit, the movable contact, and the fixed contact, where the first-lead-wire concave portion accepts insertion of the covering member of the first lead wire and the second-lead-wire concave portion accepts insertion of the covering member of the second lead wire.
According to another aspect, a temperature-switch insulation case arranged in a temperature switch that includes a temperature detection unit configured to detect a temperature so as to move a movable contact to a position that is in contact with a fixed contact and to a position that is separated from the fixed contact includes a first-insulation-case member and a second-insulation-case member each of which includes a first-lead-wire concave portion and a second-lead-wire concave portion, and which are fit into each other so as to form an accommodation space that accommodates the temperature detection unit, the movable contact, and the fixed contact, where the first-lead-wire concave portion accepts insertion of a covering member of a first lead wire that is connected to the fixed contact and that includes the covering member and the second-lead-wire concave portion accepts insertion of a covering member of a second lead wire that is connected to the movable contact and that includes the covering member.
The present invention can prevent damage to the covering member of a lead wire and can surely hold the lead wire, through a simple assembly operation.
Hereinafter, explanations will be given for the temperature switches and the temperature-switch insulation cases according to the first through sixth embodiments of the present invention by referring to the drawings.
The movable contact 2 is fixed to the bottom face of one end of a movable plate 4b, which will be described later, in the longitudinal directions (identical to for example the axial directions (Y directions) of the first and second lead wires 5 and 6, which will be described later), and moves, through an inverted operation of the movable plate 4b, to the position that is in contact with the fixed contact 3 (see
The temperature detection unit 4 includes a bimetal 4a and the movable plate 4b to detect a temperature, and thereby move the movable contact 2 to the position that is in contact with the fixed contact 3 and to a position that is separated from the fixed contact 3.
The bimetal 4a is a thermally actuated element that inverts the bending-back direction by treating the set temperature as a boundary. The movable plate 4b supports the bimetal 4a while being in surface contact with the bimetal 4a, and is elastically deformed by the inversion of the bimetal 4a and in accordance with the shape of the bimetal 4a. Note that it is desirable that the movable plate 4b be a good conductor of electricity in order to form a current path between the movable contact 2 and the second lead wire 6.
In a normal state, the bimetal 4a and the movable plate 4b have their center portions, which are in the longitudinal directions (Y directions that are identical to the axial directions of the first and second lead wires 5 and 6) as illustrated in
When the ambient temperature exceeds the set temperature, the center portions in the longitudinal directions of the bimetal 4a and the movable plate 4b are inverted to form downward-facing convex portions, and both sides of the convex portions face upward. This moves the movable contact 2 to a position that is separated from the fixed contact 3. In other words, the electric contact of the energizing circuit of the electric device is opened to break the current path.
Note that the temperature detection unit 4 is not limited to a configuration having the bimetal 4a and the movable plate 4b, and may employ a different configuration such as for example a configuration of moving a movable contact by the inflation of a gas or a liquid. The first and second lead wires 5 and 6 are flexible, and are at least partially covered by covering members 5a and 6a. The covering members 5a and 6a are elastic bodies such as for example silicone rubber, fluorocarbon rubber, or a plastic resin.
The insulation case 10 has the shape of a rectangular parallelepiped having edges that are parallel to the X, Y, or Z direction each of which is orthogonal to the others, and includes a first-insulation-case member 11 and a second-insulation-case member 12 fit into each other to form accommodation space S illustrated in
The first-insulation-case member 11 includes a first-lead-wire concave portion 11a and a second-lead-wire concave portion 11b, and the second-insulation-case member 12 includes a first-lead-wire concave portion 12a and a second-lead-wire concave portion 12b. The first-insulation-case member 11 further includes two pairs of external-lock openings 11c and 11d, a pair of near-side convex portions 11e, and one far-side convex portion (not illustrated). The second-insulation-case member 12 further includes two pairs of external-lock clicks 12c and 12d, a pair of near-side grooves 12e and 12e, and one far-side groove 12f.
The first-lead-wire concave portions 11a and 12a and the second-lead-wire concave portions 11b and 12b are parallel to the axial directions of the first and second lead wires 5 and 6 (Y directions), and have a semicylindrical shape having radiuses roughly identical to (or, desirably, somewhat greater than) those of the first and second lead wires 5 and 6. It is desirable that the first-lead-wire concave portions 11a and 12a and the second-lead-wire concave portions 11b and 12b in the axial directions (Y directions) be long enough to ensure the insulation distance in the insulation case 0.
The first-lead-wire concave portion 11a, which is for the first-insulation-case member 11, and the first-lead-wire concave portion 12a, which is for the second-insulation-case member 12, are opposed to each other in for example the Z directions, which are vertical directions, and the covering member 5a of the first lead wire 5 is inserted between them. The second-lead-wire concave portion 11b, which is for the first-insulation-case member 11, and the second-lead-wire concave portion 12b, which is for the second-insulation-case member 12, are also opposed to each other in for example the Z directions, which are vertical directions, and the covering member 6a of the second lead wire 6 is inserted between them.
For the end portions on the near side in the Y directions (right side in
As illustrated in
The pair of the near-side convex portions 11e of the first-insulation-case member 11 project toward the center side of the insulation case 10 in the arrangement directions of the first and second lead wires 5 and 6 (X directions), and are arranged at opposed positions in this arrangement directions (X directions) (in
One far-side groove 12f of the second-insulation-case member 12 is open over the upper side (one of the Z directions) and the front and back sides (both of the X directions) in
The temperature switch 1 according to the first embodiment described above includes the temperature detection unit 4 configured to detect a temperature so as to move the movable contact 2 to a position that is in contact with the fixed contact 3 and to a position that is separated from the fixed contact 3, the first lead wire 5 that is connected to the fixed contact 3 and that includes the covering member 5a, the second lead wire 6 that is connected to the movable contact 2 and that includes the covering member 6a, the first-insulation-case member 11, and the second-insulation-case member 12. The first-insulation-case member 11 includes the first-lead-wire concave portion 11a and the second-lead-wire concave portion 11b while the second-insulation-case member 12 includes the first-lead-wire concave portion 12a and the second-lead-wire concave portion 12b, and the first-insulation-case member 11 and the second-insulation-case member 12 are fit into each other so as to form accommodation space S that accommodates the temperature detection unit 4, the movable contact 2, and the fixed contact 3, where the first-lead-wire concave portions 11a and 12a accept the insertion of the covering member 5a of the first lead wire 5 and the second-lead-wire concave portions 11b and 12b accept the insertion of the covering member 6a of the second lead wire 6.
Thus, fitting the first-insulation-case member 11 and the second-insulation-case member 12 enables the first and second lead wires 5 and 6 to be held with an operation easier than in the conventional configuration that uses a filling material. Further, the first-insulation-case member 11 and the second-insulation-case member 12 are not so likely to peel from the covering members 5a and 6a of the first and second lead wires 5 and 6 as in the configuration using a filling material, eliminating the necessity to limit, in order to prevent the peeling, the way of the provision such as for example limiting the range within which the lead wires 5 and 6 can bend.
The first embodiment thus makes it possible, through a simple assembly operation, to prevent damage to the covering members 5a and 6a of the first and second lead wires 5 and 6 and to surely hold the first and second lead wires 5 and 6.
On each of the first-lead-wire concave portions 21a and 22a and the second-lead-wire concave portions 21b and 22b, a plurality of ribs 21a-1, 22a-1, 21b-1, and 22b-1 are formed that project at positions apart in the axial directions (Y directions) of the first and second lead wires 5 and 6. While two ribs exist for each of the numerals (21a-1, 22a-1, 21b-1, and 22b-1) in the example illustrated in
The plurality of ribs 21a-1 of the first-lead-wire concave portion 21a of the first-insulation-case member 21 and the plurality of ribs 22a-1 of the first-lead-wire concave portion 22a of the second-insulation-case member 22 come into contact with each other so as to tighten the covering member 5a of the first lead wire 5 illustrated in
However, while it is desirable that the plurality of the ribs 21b-1 of the second-lead-wire concave portion 21b of the first-insulation-case member 21 and the plurality of ribs 22b-1 of the second-lead-wire concave portion 22b of the second-insulation-case member 22 come into contact with each other so as to tighten the covering member 6a of the second lead wire 6 illustrated in
The second embodiment can achieve an effect that the first and second lead wires 5 and 6 can be held more surely, in addition to the effects achieved by the above first embodiment.
It is desirable that the indentations 32a-2 and 32b-2 be provided for example all along the circumference of the covering members 5a and 6a of the first and second lead wires 5 and 6 illustrated in
A near-side convex portion 41e of the first-insulation-case member 41 and a near-side groove 42e of the second-insulation-case member 42 are shorter, in the downward direction (Z direction) than a near-side convex portion 31e and a near-side groove 32e illustrated in
The fourth embodiment can achieve, in addition to the effects of the first through third embodiments, an effect that the balance (balance of stresses) of repelling forces generated by the compression of the covering members 5a and 6a of the first and second lead wires 5 and 6 can be adjusted by locking the first-insulation-case member 41 and the second-insulation-case member 42 near the portions in which these repelling forces are generated.
Examples of the second lock mechanisms may include an internal-lock click 51f for the first-insulation-case member 51 and an internal-lock opening 52g for the second-insulation-case member 52. Note that the second lock mechanism is not limited to a configuration having a click such as the internal-lock click 51f, but may employ a different configuration such as for example one using a member for achieving interference-fit. It is desirable that the internal-lock click 51f and the internal-lock opening 52g be in the middle in the arrangement directions (X directions) of the first and second lead wires 5 and 6 in the insulation case 50. The internal-lock click 51f projects downward (Z direction) from the first-insulation-case member 51 and has its tip portion projecting in one of the arrangement directions of the first and second lead wires 5 and 6 (X directions) illustrated in
The fifth embodiment enables the internal-lock click 51f and the internal-lock opening 52g, which are examples of second lock mechanisms, to more surely suppress repelling forces near the portions in which these repelling forces are generated, the repelling forces being generated by the compression of the covering members 5a and 6a of the first and second lead wires 5 and 6. This can achieve an effect that the first and second lead wires 5 and 6 can be held further surely, in addition to the effects of the first through fourth embodiments.
According to the sixth embodiment, the internal-lock click 61f and the internal-lock opening 62g cooperate with the external-lock openings 61c and 61d and the external-lock clicks 62c and 62d, have the locking directions orthogonal to each other, and thereby can further surely suppress repelling forces caused by the compression of the covering members 5a and 6a of the first and second lead wires 5 and 6 and also can ensure the symmetry of the insulation case 60 in the arrangement directions (X directions) of the first and second lead wires 5 and 6. This can achieve an effect that the first and second lead wires 5 and 6 can be held further surely, in addition to the effects of the first through fifth embodiments.
While the first through sixth embodiments of the present invention have been explained above, the present invention is included in the scope of the inventions described in the claims and their equivalents. Below, the inventions described in the original claims of the present application as filed are added as appendixes.
Appendix 1. A temperature switch comprising:
a temperature detection unit configured to detect a temperature so as to move a movable contact to a position that is in contact with a fixed contact and to a position that is separated from the fixed contact;
a first lead wire that is connected to the fixed contact and that includes a covering member;
a second lead wire that is connected to the movable contact and that includes a covering member; and
a first-insulation-case member and a second-insulation-case member each of which includes a first-lead-wire concave portion and a second-lead-wire concave portion, and which are fit into each other so as to form an accommodation space that accommodates the temperature detection unit, the movable contact, and the fixed contact, where the first-lead-wire concave portion accepts insertion of the covering member of the first lead wire and the second-lead-wire concave portion accepts insertion of the covering member of the second lead wire.
Appendix 2. The temperature switch according to appendix 1, wherein
a plurality of ribs that project at positions apart in axial directions of the first lead wire are formed on the first-lead-wire concave portions,
a plurality of ribs that project at positions apart in axial directions of the second lead wire are formed on the second-lead-wire concave portions,
the plurality of ribs of the first-lead-wire concave portion of the first-insulation-case member and the plurality of ribs of the first-lead-wire concave portion of the second-insulation-case member come into contact with each other so as to tighten the covering member of the first lead wire all along circumference of the covering member of the first lead wire, and
the plurality of ribs of the second-lead-wire concave portion of the first-insulation-case member and the plurality of ribs of the second-lead-wire concave portion of the second-insulation-case member come into contact with each other so as to tighten the covering member of the second lead wire all along circumference of the covering member of the second lead wire.
Appendix 3. The temperature switch according to appendix 2, wherein
the first-lead-wire concave portion and the second-lead-wire concave portion of at least one of the first-insulation-case member and the second-insulation-case member include an indentation between the plurality of ribs.
Appendix 4. The temperature switch according to appendix 1, wherein
the first-lead-wire concave portions and the second-lead-wire concave portions extend in axial directions of the first lead wire and the second lead wire parallel to each other, and are arranged in opposed directions of the first-lead-wire concave portion and the second-lead-wire concave portion of the first-insulation-case member and the first-lead-wire concave portion and the second-lead-wire concave portion of the second-insulation-case member and in arrangement directions orthogonal to the axial directions,
each of the first-insulation-case member and the second-insulation-case member further includes a pair of first lock mechanisms that are positioned on faces on both sides sandwiching the accommodation space in the arrangement directions and that are for locking the first-insulation-case member and the second-insulation-case member,
the first-lead-wire concave portion and the second-lead-wire concave portion are parallel to the axial direction of the first lead wire and the second lead wire, and
the pair of the first lock mechanisms intersect a plane that contains midpoints of the first-lead-wire concave portion and the second-lead-wire concave portion in the axial directions and that is orthogonal to the axial directions.
Appendix 5. The temperature switch according to appendix 1, wherein
each of the first-insulation-case member and the second-insulation-case member further includes a second lock mechanism that is positioned between the first-lead-wire concave portion and the second-lead-wire concave portion and that is for locking the first-insulation-case member and the second-insulation-case member.
Appendix 6. The temperature switch according to appendix 5, wherein
the first-lead-wire concave portions and the second-lead-wire concave portions extend in axial directions of the first lead wire and the second lead wire parallel to each other, and are arranged in opposed directions of the first-lead-wire concave portion and the second-lead-wire concave portion of the first-insulation-case member and the first-lead-wire concave portion and the second-lead-wire concave portion of the second-insulation-case member and in arrangement directions orthogonal to the axial directions,
each of the first-insulation-case member and the second-insulation-case member further includes a pair of first lock mechanisms that are positioned on faces on both sides sandwiching the accommodation space in the arrangement directions and that are for locking the first-insulation-case member and the second-insulation-case member, and
the second lock mechanisms lock the first-insulation-case member and the second-insulation-case member in directions that are orthogonal to directions in which the pair of the first lock mechanisms lock the first-insulation-case member and the second-insulation-case member.
Appendix 7. A temperature-switch insulation case arranged in a temperature switch that includes a temperature detection unit configured to detect a temperature so as to move a movable contact to a position that is in contact with a fixed contact and to a position that is separated from the fixed contact, the temperature-switch insulation case comprising:
a first-insulation-case member and a second-insulation-case member each of which includes a first-lead-wire concave portion and a second-lead-wire concave portion, and which are fit into each other, where the first-lead-wire concave portion accepts insertion of a covering member of a first lead wire that is connected to the fixed contact and that includes the covering member and the second-lead-wire concave portion accepts insertion of a covering member of a second lead wire that is connected to the movable contact and that includes the covering member.
Number | Date | Country | Kind |
---|---|---|---|
2016-012398 | Jan 2016 | JP | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/JP2016/083299 | 11/9/2016 | WO | 00 |