JP7319201B2 - Terminal block - Google Patents

Description

TECHNICAL FIELD The present invention relates to a terminal block, and more particularly to a terminal block for cable connection between an indoor unit and an outdoor unit of an air conditioner and a cable connection for a water heater or the like.

The terminal block described in Patent Document 1 has a relay and a temperature sensor inside, and when the temperature limit of the temperature sensor is exceeded, a detection signal from the temperature sensor activates the relay to cut off the power supply. This realizes an overheating protection function that can prevent situations in which the temperature rises abnormally, fires occur due to arcs, and electrical equipment is damaged.

Registered Utility Model No. 3135586

However, in the terminal block described in Patent Document 1, when a plurality of input terminals are provided, due to the difference in the distance between each input terminal and the temperature sensor, the temperature rise at the input terminal near which the temperature sensor is arranged is accurate and accurate. While it is sensed quickly, the temperature rise at the input end located far from the temperature sensor cannot be sensed accurately, and could lead to overheating. In recent years, in order to efficiently provide a large number of input terminals on a small terminal block, a form in which the input terminals are arranged three-dimensionally has also been proposed. There was a growing concern that the overheating protection function would not function sufficiently due to the increasing proportion of the edges.

Therefore, the present invention provides a terminal block that is capable of reliably protecting each terminal from overheating, even if a plurality of terminals having input terminals are provided and the distance from each terminal to the temperature sensor and the arrangement thereof are different. intended to provide

In order to solve the above problems, the terminal block of the present invention includes a main body, a plurality of metal terminals inserted into the main body, a temperature sensor arranged in the main body, and a metal transmission terminal. The material constituting the main body is a material having a lower thermal conductivity than the terminal and the heat transfer member, and the terminal includes a first terminal provided close to the temperature sensor and a temperature sensor. The heat transfer member has one end proximate to the temperature sensor, the other end in contact with the second terminal, and is connected to the first terminal. It is characterized in that they are arranged so as not to come into contact with each other.

In the terminal block of the present invention, the first terminal is arranged at a position at least partially overlapping the temperature sensor or at a position below the temperature sensor in the vertical direction, and the second terminal is arranged at the It is preferably arranged above both the 1 terminal and the temperature sensor.

In the terminal block of the present invention, it is preferable that the first terminal and the heat transfer member are arranged so that heat transfer conditions with respect to the temperature sensor are substantially the same.

In the terminal block of the present invention, it is preferable that the first terminal and the heat transfer member are arranged such that their thermal distances from the temperature sensor are approximately the same.

In the terminal block of the present invention, the main body includes an accommodating portion that accommodates the temperature sensor therein, the first terminal is in contact with the first wall that constitutes the accommodating portion, and one end of the heat transfer member is: It is preferably in contact with a second wall that constitutes the housing portion and is separate from the first wall.

In the terminal block of the present invention, it is preferable that the first wall and the second wall have approximately the same thickness, and the temperature sensor is in contact with the first wall and the second wall.

In the terminal block of the present invention, it is preferable that the temperature sensor is a fuse that is fused when the temperature exceeds a predetermined temperature, and that the fuse disconnects an electric circuit including a plurality of terminals.

In the terminal block of the present invention, the terminal and heat transfer member are preferably made of brass or copper.

In the terminal block of the present invention, it is preferable that the body portion is made of polybutylene terephthalate.

According to the present invention, even if a plurality of terminals having input terminals are provided and the distances and arrangements from the respective terminals to the temperature sensors are different, each terminal can be reliably protected from overheating.

(a) is a perspective view showing an overview of a terminal block according to an embodiment of the present invention, and (b) is a plan view of the terminal block shown in (a). 1(a) is a perspective view showing the internal configuration of a main body in an embodiment of the present invention, (b) is a perspective view showing the configuration of a first terminal, and (c) is a perspective view showing the configuration of a second terminal. FIG. 3(a) and 3(b) are perspective views of the configuration of the heat transfer member according to the embodiment of the present invention, viewed from different angles. FIG. 1(a) and 1(b) are cross-sectional views taken along line IV-IV' of FIG. (a) and (b) are partially enlarged cross-sectional views taken along line IV-IV' of FIG. (b) is a diagram showing a state in which the assembly of (a) is completed. It is a circuit diagram in the terminal block which concerns on embodiment of this invention.

Hereinafter, a terminal block according to an embodiment of the present invention will be described in detail with reference to the drawings. The terminal block according to this embodiment is suitable for, for example, air conditioners (air conditioners), power conditioners, water heaters, jet towels, and electrically heated toilet seats.
Each figure shows XYZ coordinates as reference coordinates. In the following description, the Z1-Z2 direction is referred to as the up-down direction, the X1-X2 direction is referred to as the front-rear direction, and the Y1-Y2 direction is referred to as the left-right direction. The X1-X2 direction and the Y1-Y2 direction are perpendicular to each other, and the XY plane containing them is perpendicular to the Z1-Z2 direction. Also, a state viewed from the upper side (Z1 side) to the lower side (Z2 side) is sometimes called a planar view.

FIG. 1(a) is a perspective view showing the appearance of the terminal block 10 according to the present embodiment, (b) is a plan view of the terminal block 10, and FIG. 3B is a perspective view showing the structure of the first terminal 31, and FIG. 3C is a perspective view showing the structure of the second terminal 32. FIG. 3A and 3B are perspective views of the configuration of the heat transfer member 60 viewed from different angles. 4(a) and (b) are cross-sectional views taken along line IV-IV' of FIG. 1(b), and (a) is viewed along the 4A, 4A' direction (from left to right). Cross-sectional view, (b) is a cross-sectional view seen along the direction 4B, 4B' (direction from right to left). 5B is a partially enlarged cross-sectional view of FIG. 4A, and FIG. 5A is a cross-sectional view of the same position as FIG. FIG. 4 is a diagram showing a state before the member 60 and the second screw 42 are assembled; FIG. 6 is a circuit diagram of the terminal block 10. As shown in FIG.

As shown in FIGS. 1A, 1B, or 2A, the terminal block 10 includes a body portion 20, six terminals 31, 32, 33, 34 inserted into the body portion 20, 35 , 36 , a temperature sensor 50 and a heat transfer member 60 . Further, the terminal block 10 includes a first screw 41 screwed onto the front end portion of the first terminal 31 , a second screw 42 screwed onto the front end portion of the second terminal 32 , and both ends of the third terminal 33 . a third screw 43 and a seventh screw 47 screwed together, a fourth screw 44 screwed onto the front end of the fourth terminal 34, and a fifth screw screwed onto the front end of the fifth terminal 35 45 and a sixth screw 46 screwed to the front end of the sixth terminal 36 . Here, the third terminal 33 is folded up and down, and two screws 43 and 47 are arranged at both ends thereof.

The terminal block 10 is provided with six terminals 31 to 36 and screws corresponding thereto. The number of terminals may be any number greater than or equal to two, as long as the second terminal 32 is provided distally.

A plurality of cables (not shown) are inserted into the terminal block 10 from the outside of the main body 20, and these cables are sandwiched between corresponding terminals and corresponding screw washers. For example, taking the first terminal 31 as an example, the first screw 41 and one end 31a (front end) of the first terminal 31 (see FIG. 2(b)) hold the core wire of the cable. is configured, and the other end 31b (rear end) of the first terminal 31 is configured as an output end (see FIG. 2(b) and FIG. 6). Terminals 32 other than the first terminal 31 have such a configuration.

The main body 20 is made of, for example, a resin material that has low thermal conductivity, heat resistance, and electrical insulation. This thermal conductivity is preferably at least sufficiently lower than those of the six metal terminals 31 to 36 and the heat transfer member 60, and is preferably 0.5 W/m·K or less, for example. When polybutylene terephthalate is used for the main body 20, its thermal conductivity is about 0.25 W/m·K.

As shown in FIGS. 5(a) and 5(b), the body portion 20 includes a housing portion 20a as a space for housing the temperature sensor 50 therein. The accommodation portion 20a surrounds the temperature sensor 50 in the front-back direction (X1-X2 direction) and the up-down direction (Z1-Z2 direction), and the temperature sensor 50 is inserted into the accommodation portion 20a along the left-right direction. . More specifically, the housing portion 20a has four walls, a bottom wall portion 21 as a first wall portion, a rear wall portion 22 as a second wall portion, a front wall portion 23, and an upper wall portion 24. It surrounds the temperature sensor 50 . The temperature sensor 50 has a rectangular parallelepiped outer shape, and the front and rear surfaces and the upper and lower surfaces are in contact with these four walls. Furthermore, if the thicknesses of these four wall portions are the same, members in contact with or close to the wall portions, such as the first terminal 31 in contact with the bottom wall portion 21 and the heat transfer member in contact with the rear wall portion 22 The thermal distance between 60 and temperature sensor 50 can be the same. Here, the thermal distance means the distance corresponding to the heat conduction efficiency based on the thermal conductivity and thickness of the material, air, etc., interposed between the two members.

Furthermore, depending on the design conditions of the terminal block 10, (1) the material and thickness of the four walls 21 to 24 that make up the housing portion 20a, (2) members in contact with or close to these walls, such as the first 1. By adjusting the material, thickness, gap between the terminal 31 and the heat transfer member 60 and the wall, and (3) the facing area between these members and the walls 21 to 24, etc. The heat radiation amount (atmospheric heat amount) generated by the current application can be made variable, and the heat transfer conditions for transmitting the heat radiation amount in each terminal to the temperature sensor 50 can be made the same.

It is also possible to dispose the temperature sensor 50 in the accommodation portion 20a so that there is a gap between the walls 21 to 24. In this case, the amount of the gap between each wall is substantially the same. Then, the thermal distances of the members contacting or adjoining each wall portion can be substantially the same.

As shown in FIG. 1(b) or FIG. 2(a), six terminals 31 to 36 are inserted into the main body 20 so as to extend in the front-rear direction. These terminals are arranged in two levels, upper and lower, with the first terminal 31 and sixth terminal 36 arranged in the lower level, and the second terminal 32, fourth terminal 34 and fifth terminal 35 in the upper level. are arranged in order. The second terminal 32 is arranged above the first terminal 31 and the fourth terminal 34 is arranged above the sixth terminal 36 . Further, a third terminal 33 is arranged between the second terminal 32 and the fourth terminal 34 in the left-right direction. It is formed to extend forward and backward. The front ends of the terminals 31, 33 (lower) and 36 located in the lower stage are located forward of the front ends of the terminals 32, 33 (upper), 34 and 35 located in the upper stage.

The six terminals 31 to 36 are made of metal material and formed into long plates of the same thickness, and are made of, for example, brass or copper, and have high thermal conductivity and electrical conductivity. The shapes of the six terminals can be arbitrarily set according to the design conditions of the terminal block 10. FIG.

The first terminal 31 shown in FIG. 2(b) has the same shape as the sixth terminal 36, and has a threaded hole in one longitudinal end 31a (front end) through which the first screw 41 penetrates in the thickness direction. 31c is provided and used as an input end, and the other end 31b (rear end) is used as an output end as described above. The second terminal 32 shown in FIG. 2(c) has the same shape as the fourth terminal 34 and the fifth terminal 35, and has a second screw 42 at one end 32a (front end) in the longitudinal direction. A threaded hole 32c is provided to pass through and is used as an input end, and the other end 32b (rear end) is used as an output end as described above.

When the rear end 31b of the first terminal 31 is aligned with the rear end 32b of the second terminal 32 in the front-rear direction (X1-X2 direction), the front end 31a of the second terminal 32 It has a length that protrudes forward from the front end portion 32a. As a result, as shown in FIG. 1B, the first screw 41 inserted and screwed into the screw hole 31c of the first terminal 31 and the washer disposed between the first screw 41 and the first terminal 31 41a is located on the front side of the second terminal 32 in plan view. Here, the first screw 41 and the washer 41a are made of metal such as iron.

The temperature sensor 50 is a fuse that is blown when the temperature exceeds a predetermined temperature, and is connected to the detector 53 via wirings 51 and 52 (see FIG. 6). The predetermined temperature is set higher than the temperature when a normal amount of current is applied to each terminal, and set to a temperature sufficiently lower than the heat resistance temperature and melting point of the material forming the main body 20 . Current enters the temperature sensor 50 from, for example, the third terminal 33 via the wiring 51 to the temperature sensor 50 . When the temperature of the temperature sensor 50 exceeds the above-described predetermined temperature, it is melted down, and current does not flow to the detection portion 53, so that it is detected that the inside of the main body portion 20 has reached a high temperature. This detection result is output to a control unit (not shown) of the equipment provided with the terminal block 10, and the electric circuit including the terminals 31 to 36 is disconnected.

The predetermined temperature is set as a temperature corresponding to the amount of heat released when a large current of a predetermined amount or more flows through the terminal and the terminal is overheated. Since the temperature sensor 50 melts down when the predetermined temperature set in this way is exceeded, it is possible to realize protection from overheating. In addition, if the screws are not sufficiently tightened against the terminals, the contact between the two becomes unstable, so there is a risk of overheating due to the concentrated flow of current in areas where the contact area is small. Also in this case, the temperature sensor 50 melts when the temperature corresponding to the amount of heat released exceeds the predetermined temperature, so the overheat protection function reliably functions.

As shown in FIGS. 3(a) and 3(b), the heat transfer member 60 is formed by bending a metal plate material having a certain thickness. −X2 direction) and the left-right direction (Y1-Y2 direction), a connecting portion 62 extending downward (Z2 direction) from the right end (Y1 side end) of the top surface portion 61, and a lower surface portion 63 extending leftward (Y2 direction) from the front end (X1 side end) of the connecting portion 62 . The heat transfer member 60 is made of brass or copper, for example, and has high thermal conductivity.

The shape of the heat transfer member 60 is not limited to that shown in FIGS. 3(a) and 3(b). A configuration is also possible in which the lower surface portion is provided so as to extend to the right from the .

As shown in FIG. 2(a), FIG. 4(a), (b), or FIG. and the washer 42a of the second screw 42, the connecting portion 62 and the lower surface portion 63 are inserted into the space 20b adjacent to the rear of the housing portion 20a, and the lower surface portion 63 is in surface contact with the rear wall portion 22. . Therefore, the lower surface portion 63 is arranged to face the temperature sensor 50 with the rear wall portion 22 interposed therebetween, and is close to the temperature sensor 50 . Also, the lower end of the lower surface portion 63 is out of contact with the first terminal 31 by the bottom wall 25 of the space 20b. That is, the heat transfer member 60 is arranged so that one end is close to the temperature sensor 50 and the other end is in contact with the second terminal 32 but not in contact with the first terminal 31 .

Here, the second screw 42 and the washer 42a are made of metal such as iron. made of the same metal as

If the heat transfer conditions from the first terminal 31 to the temperature sensor 50 and the heat transfer conditions between the heat transfer member 60 and the temperature sensor 50 are the same or substantially the same, the lower surface portion 63 of the heat transfer member 60 may contact the temperature sensor 50 or the upper surface portion 61 of the heat transfer member 60 may be positioned close to the second terminal 32 . It should be noted that the substantially same heat transfer condition means that the fusing temperature of the temperature sensor 50 is within a range that can be regarded as substantially the same in view of the specifications of the terminal block 10 and the like.

As shown in FIG. 5(a), the second terminal 32 is inserted from the rear side to the front side into the body portion 20 into which the first terminal 31 and the first screw 41 have been previously inserted, and the space 20b rises. It is arranged so as to cover from the inside (see FIG. 5(b)). Next, as shown in FIG. 5A again, the heat transfer member 60 is inserted downward, and the second screw 42 is inserted downward from above the heat transfer member 60 . As a result, as shown in FIG. 5B, the upper surface portion 61 of the heat transfer member 60 is in surface contact with the upper surface of the second terminal 32, and the lower surface portion 63 is in surface contact with or close to the rear wall portion 22. . The second screw 42 is vertically penetrated and screwed into the heat transfer member 60 and the second terminal 32 in this state. By disposing between the washer 42 a of the second screw 42 and the upper surface portion 61 and screwing the second screw 42 onto the heat transfer member 60 and the second terminal 32 and tightening, the cable and the second terminal 32 are connected. are in electrical conduction with each other. At this time, the second screw 42 , the upper surface portion 61 , and the second terminal 32 are thermally connected to each other, and heat generated when current is applied from the cable through the second terminal 32 is transferred to the lower surface through the upper surface portion 61 . It conducts to the portion 63 and further to the temperature sensor 50 via the front wall portion 23 .

The process of assembling the second terminal 32, the contact state of each member, and the electrical contact are the same for the first terminal 31 and other terminals. In the first terminal 31, the first screw 41 and the first terminal 31 are thermally connected to each other, and heat is generated when current is applied through the first terminal 31 from a cable (not shown) sandwiched between them. is conducted to the temperature sensor 50 through the bottom wall portion 21 .

By making the heat transfer conditions from the first terminal 31 to the temperature sensor 50 and the heat transfer conditions from the heat transfer member 60 to the temperature sensor 50 the same or substantially the same, the heat generated by the current flowing through the second terminal 32 can be detected by the temperature sensor 50 in the same manner as the amount of heat released by the current flowing through the first terminal 31 . Therefore, by providing the heat transfer member 60, regardless of the distance from the temperature sensor 50 or the arrangement with respect to the temperature sensor 50, it is possible to similarly quickly and reliably detect the temperature change due to heat.

Here, as shown in FIGS. 2, 4, and 5, the temperature sensor 50 is positioned above the first terminal 31 in the vertical direction (Z1-Z2 direction) and However, regardless of the distance from the temperature sensor 50 and the arrangement with respect to the temperature sensor 50, the effect that the temperature change due to heat can be detected quickly and reliably in the same way is the first. This is also obtained when one or both of the first terminal 31 and the second terminal 32 are positioned so as to partially overlap the temperature sensor 50 in the vertical direction.
Although the present invention has been described with reference to the above embodiments, the present invention is not limited to the above embodiments, and can be improved or changed within the scope of the purpose of improvement or the spirit of the present invention.

As described above, the terminal block according to the present invention can reliably protect each terminal from overheating, even if a plurality of terminals are provided and the distance from each terminal to the temperature sensor and the arrangement are different. It is useful in that it allows

REFERENCE SIGNS LIST 10 terminal block 20 main body 20a housing 20b space 21 bottom wall 22 rear wall 23 front wall 24 upper wall 25 bottom wall 31 first terminal 31a front end 31b rear end 31c screw hole 32 second terminal 32a front end Part 32b Rear end 32c Screw hole 33 Third terminal 34 Fourth terminal 35 Fifth terminal 36 Sixth terminal 41 First screw 41a Washer 42 Second screw 42a Washer 43, 44, 45, 46, 47 Screw 50 Temperature sensor 51 , 52 wiring 53 detection part 61 upper surface part 62 connecting part 63 lower surface part

Claims (9)

a main body;
a plurality of metal terminals inserted into the main body;
a temperature sensor disposed within the body;
a metal heat transfer member,
A material forming the main body is a material having a lower thermal conductivity than the terminal and the heat transfer member,
The terminal has a first terminal provided close to the temperature sensor and a second terminal provided farther than the first terminal with respect to the temperature sensor,
The terminal block, wherein the heat transfer member is arranged so that one end thereof is close to the temperature sensor and the other end is in contact with the second terminal but not in contact with the first terminal. The first terminal is arranged at a position at least partially overlapping with the temperature sensor or at a position below the temperature sensor in the vertical direction,
2. The terminal block according to claim 1, wherein said second terminal is arranged above both said first terminal and said temperature sensor in the vertical direction. 3. The terminal block according to claim 1, wherein the first terminal and the heat transfer member are arranged so that heat transfer conditions with respect to the temperature sensor are substantially the same. 4. The terminal block according to claim 3, wherein said first terminal and said heat transfer member are arranged such that their thermal distances from said temperature sensor are substantially the same. The main body includes an accommodation portion that accommodates the temperature sensor therein,
The first terminal is in contact with a first wall portion that constitutes the accommodation portion,
5. The terminal block according to any one of claims 1 to 4, wherein one end of said heat transfer member is in contact with a second wall portion constituting said housing portion, which is different from said first wall portion. . the first wall and the second wall have substantially the same thickness;
6. The terminal block according to claim 5, wherein said temperature sensor is in contact with said first wall and said second wall. 7. The terminal according to any one of claims 1 to 6, wherein the temperature sensor is a fuse that is fused when a predetermined temperature is exceeded, and the fuse disconnects an electric circuit including the plurality of terminals. stand. The terminal block according to any one of claims 1 to 7, wherein the terminal and the heat transfer member are made of brass or copper. 9. The terminal block according to claim 8, wherein said body portion is made of polybutylene terephthalate.