JP2006079866A - Terminal block with temperature fuse - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a terminal block with a temperature fuse having excellent insertion capability and connection capability of a lead, and capable of preventing a short circuit caused by a foreign substance. <P>SOLUTION: In this terminal block equipped with a temperature fuse, a contact housing part opened backward is formed in a housing of the terminal block to house contacts from the back face; a lead insertion hole is formed in a surface of the housing by boring it; and leads are allowed to be connected from the front side. In this case, it is preferable that a lead guide part is formed on the contact housing part side of the lead insertion hole, and a taper surface is formed on the front side of the lead insertion hole. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a terminal block provided with a thermal fuse.

Terminal blocks are used to connect indoor units and outdoor units with cables for air conditioners, water heaters, etc., and this type of terminal block is used when the cable connected to the terminal terminal is poorly connected. A thermal fuse is installed to detect heat generation.
Conventionally, as shown in FIG. 6 (a), the terminal block 110 is provided with two relay contacts 130a and 130b, and the input side leads 115a and 116a and the output side leads 115b and 116b. And a thermal fuse 117 is connected between the input-side relay contact 130a and the output-side relay contact 130b.
When replacing the thermal fuse 117, the input side lead 116a is removed from the contact 130a, the output side lead 116b is removed from the contact 130b, and the fuse 117 is removed for replacement.
The connection of each lead to the contacts 130a and 130b is shown in FIG. 6 (b), which is a perspective view of the contact portion. FIG. 7 is a perspective view of the contact, and the leads provided in the contacts 130a, 130b. Each lead is inserted from the insertion hole 123, and the core wire of the lead is inserted and held in the connection part 131 between the spring part 132 of the contact 130a and the plate-like conductive part 133.
8 (a) and 8 (b) are explanatory views corresponding to the longitudinal section in the vicinity of the contact in FIG. 6 (a).
The lead 115 has the core 116 inserted into the lead insertion hole 123 and is inserted and clamped into the contact portion 131.
In the conventional terminal block, since the lead insertion hole 123 is small, in order to secure the mountability by forming this lead insertion hole on the front side, the contact is also formed by forming a storage portion on the front side of the terminal block.
However, as shown in FIG. 8 (a), the conductive foreign material 101 falls and is placed between the contacts 130a and 130b that are barely fitted on the front side 111 of the terminal block 110, so that the contact between the contacts 130a and 130b. There was a risk of short circuit.
Further, although the contacts 130a and 130b are manufactured by pressing a metal plate or the like, for example, the contacts 130a and 130b may be connected to the connection portion 131 in an inclined state like the lead 115c, and the core wire 116c may be poorly connected. there were.
Japanese Patent Application Laid-Open No. 10-106653 discloses a structure in which a tab-shaped terminal is raised toward a fuse mounting portion, and a notch is provided in the terminal to fit a fuse. was there.

Japanese Patent Laid-Open No. 10-106653

  In view of the above technical problems, an object of the present invention is to provide a terminal block with a thermal fuse that is excellent in lead insertion and connectivity and can prevent short-circuiting due to foreign matter.

  The technical gist of the present invention is that in a terminal block provided with a thermal fuse, a housing for the terminal block is formed with a contact storing portion that opens toward the back side, contacts are stored from the back side, and holes are drilled on the surface of the housing. Thus, a lead insertion hole is provided so that leads can be connected from the surface side.

Here, the contact storage portion opened toward the back side is a purpose of forming a recess for storing the contact from the back surface of the housing toward the front surface, and inserting and holding the contact in the recess.
In the contact, a lead connection portion is formed in the housing front side (contact housing portion back side) direction.
Further, by providing a lead insertion port by drilling in the surface of the housing, the front side of the terminal block housing acts as a cover wall surface for the contact.
As a result, foreign matter can be prevented from falling on the contacts, and short-circuiting between contacts due to conductive foreign matter can be prevented.
Usually, the contact is provided with at least two contacts on the housing for connecting the lead (wire) wire on the input side of the thermal fuse and for relaying the output side connecting the lead (wire) wire on the output side. Are connected between the contacts, and the thermal fuse is energized through the contacts.

Providing a taper surface for leading the lead so that the inner wall of the hole is inclined toward the front side on the front side inner periphery of the lead insertion hole formed in the terminal block housing not only improves lead connectivity, The lead can be held by fitting the outer covering portion of the lead and the inner diameter of the lead insertion hole.
If the lead guide portion is provided on the contact side of the lead insertion hole up to the vicinity of the lead connecting portion, the lead connectivity is further improved.
For example, the lead guide portion may be provided in the mold so that the inner wall of the lead insertion hole extends from the front side wall surface of the contact storage portion toward the contact connection portion.
As a result, the lead insertion direction is reliably determined by the lead guide portion, and the lead core wire is accurately guided and connected to the lead connection portion, so that it is possible to prevent poor connection due to the oblique insertion attachment of the lead.

In the terminal block with a thermal fuse according to the present invention, the contact is provided by providing a contact housing portion opened on the back side of the housing, and the front side of the contact is covered by the housing. To prevent short-circuiting between contacts due to negative foreign matter.
If the taper surface is provided on the inner wall of the lead insertion hole, the lead can be easily inserted into the lead insertion hole, and a lead guide portion extending toward the lead connection portion of the contact is provided on the contact storage portion side of the lead insertion hole. And prevent diagonal connection of leads.

Embodiments of a terminal block with a thermal fuse according to the present invention will be described with reference to the drawings.
FIG. 1A is a plan view of the terminal block, and FIG. 1B is a perspective view of a main part drawn through the contacts 30a and 30b of the terminal block 10, showing a state in which leads are inserted.
This terminal block 10 is used, for example, in an air conditioner, a water heater, or the like, and is used for connecting an indoor unit and an outdoor unit with a cable.
FIG. 5 shows an example of connecting a cable to the terminal block according to the present invention.
A cable insertion hole for inserting the core wire 1a of the cable 1 is provided on the right side surface of the terminal block 10, and the cable core wire 1a is inserted into the cable insertion hole so that the cable core wire 1a is attached to the terminal terminal using, for example, a spring member. The terminal terminal 13 and the cable 1 are connected by pressing and clamping.
An in-flight circuit is connected to the connection portion 13 a of the terminal terminal 13.

As shown in FIG. 1B, the housing 20 of the terminal block 10 is provided with a concave contact housing portion 21 with a contact insertion port 22 opened on the back side 12 of the terminal block.
Contacts 30a and 30b are attached to the contact storage portion 21 so as to contact the back side (terminal block front side) 21a of the contact storage portion.
As shown in FIG. 1A, the harness lead 15a connected to the connector 14 connected to the in-flight circuit is connected to the temperature fuse lead 16a via the input-side relay contact 30a, and the temperature fuse lead 16b is It is connected to the connector 14 by the lead 15b of the harness through the contact 30b for output side relay.
When the cable is connected to the terminal 13 of the terminal block 10 and energized, the temperature fuse 17 is blown by the fuse energizing current when the temperature of the terminal block rises above the set temperature due to poor cable connection. It has a structure for detecting defects.
The thermal fuse 17 is replaced by removing the leads 16a and 16b from the contacts.
As shown in FIG. 1 (b), the contacts 30a and 30b are provided between the surface of the terminal block 10 on the front side 11 by providing a recessed contact storage portion 21 on the back side 12 of the terminal block. A cover portion 20a having a predetermined thickness is formed, and a lead insertion hole 23 penetrating from the surface of the terminal block front side 11 to the contact accommodating portion 21 is provided in the cover portion 20a.
As shown in a perspective view of the contact in FIG. 2, the contact 30 a includes a leaf spring-like spring portion 32 and a conductive portion 33 facing the spring portion.
The spring portion 32 includes a groove portion 32 a that is recessed from the tip to the center, and the lead core wire is inserted into the lead connection portion 31 between the conductive portion 33 and the spring portion groove portion 32 a, and the elastic force of the spring portion 32. The lead core wire is pressed between the conductive portion 33 and connected.

FIG. 3A shows a contact portion of the cross-sectional view taken along line AA in FIG. 1A, and FIG. 3B shows a contact portion of the cross-sectional view taken along line BB.
Since the contacts 30a and 30b are fitted into the contact storage portion 21 which is a recess opened on the back side 22 of the terminal block, the front side of the contacts 30a and 30b is covered by forming a cover portion 20a with a mold of the housing 20. .
This prevents foreign matter from falling on the contacts 30a and 30b, and prevents a short circuit between the contacts 30a and 30b due to conductive foreign matter falling.
The cover portion 20a is provided with a lead insertion hole 23 penetrating from the outer side (front surface) of the housing 20 toward the lead connection portion 31.
The inner wall of the lead insertion hole 23 is a tapered surface 23a having a diameter reduced along the lead insertion direction.
By forming the tapered surface 23a, the leads 15 and 16 can be easily inserted into the lead insertion hole 23, and the position of the inserted lead is determined by a small inner diameter portion inside.
The contact side of the lead insertion hole 23 protrudes in a rib shape so that the inner wall of the lead insertion hole 23 extends substantially toward the lead connection part 31 with the back side wall surface 21b of the contact storage part 21 extending toward the lead connection part 31. Forming.
As shown in FIG. 3B, the lead guide portion 24 is formed integrally with the housing 20 between the contact conductive portion 33 and the contact spring portion 32 as shown in FIG.
As a result, the lead insertion direction can be determined by the lead guide portion 24, and the lead core wires 15c and 16c can be smoothly guided and connected to the lead connection portion 31 to prevent connection failure due to the oblique insertion attachment of the lead.

A method of connecting leads to the lead connecting portion will be described with reference to FIG.
FIG. 4 depicts a longitudinal section of the terminal block shown in FIGS. 3 (a) and 3 (b) side by side.
The leads 15 and 16 first insert the lead core wire 15c into the lead insertion hole 23 as shown in FIG.
This insertion is easy to insert because a tapered surface 23a is formed on the inner wall of the lead insertion hole.
When the leads 15 and 16 are further inserted as shown in FIG. 4B, the lead core wires 15c and 16c first converge toward the lead connecting portion 31 to a size that fits the lead core wire outer shape. Is positioned by.
Further, the lead core wires 15 c and 16 c are guided by the lead guide portion 24 facing the tip between the spring portion 32 and the conductive portion 33 of the contacts 30 a and 30 b and inserted into the lead connecting portion 31.
Next, it is further inserted along the groove portion 32a formed in the spring portion 32, and the connection completion state shown in FIG.
Thus, the lead can be inserted and connected easily and reliably.

(A) The top view of the terminal block with a thermal fuse which concerns on this invention is shown. (B) A perspective view of the main part in the vicinity of the contact is shown. A perspective view of a contact is shown. (A) The explanatory view showing the contact part of an AA line section is shown. (B) An explanatory view showing a contact portion of a cross section taken along line BB. An explanatory view of a lead connection method is shown. The explanatory view in the state where the cable was connected to the terminal block is shown. An example of a conventional terminal block is shown. An example of a conventional contact is shown. The conventional connection method is shown.

Explanation of symbols

1 Cable 1a Cable core 10 Terminal block with thermal fuse 11 Terminal block front side (front)
12 Back side of terminal block (back side)
13 Terminal terminal 13a Terminal terminal connection portion 14 Connector 15, 15a, 15b Harness lead 15c Harness lead core wire 16, 16a, 16b Thermal fuse lead 16c Thermal fuse lead core wire 17 Thermal fuse 20 Housing 20a Cover portion 21 Contact Storage part 21a Back side of contact storage part (terminal block front side)
21b Deep side (terminal block front side) wall surface 22 of contact storage part 22 Contact insertion port 23 Lead insertion hole 23a Tapered surface 24 Lead guide part 30a, 30b Contact 31 Contact lead connection part 32 Contact spring part 32a Contact spring part groove 33 Contact conductive part

Claims (3)

  In a terminal block equipped with a thermal fuse, the housing of the terminal block is formed with a contact storage portion that opens toward the back side to store the contact from the back side, and a lead insertion hole is provided by drilling in the surface of the housing. Terminal block with thermal fuse, characterized in that lead connection is possible.   2. The terminal block with a thermal fuse according to claim 1, wherein a lead guide portion is formed on a contact housing portion side of a lead insertion hole formed in the housing of the terminal block.   3. The terminal block with a thermal fuse according to claim 1, wherein a taper surface is formed on a front side of the lead insertion hole formed in the housing of the terminal block.

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