Technical Field
[0001] The present invention relates to a lead wire terminal block to which a large number
of lead wires are connected and an electric device connection socket including the
lead wire terminal block.
Background Art
[0002] For example, a device disclosed in PTL 1 is known as an electric device connection
socket.
[0003] The electric device connection socket disclosed in PTL 1 is a device that connects
an electric device, such as a relay or a timer, to an external circuit through lead
wires and includes an electric device terminal block and a lead wire terminal block.
[0004] In the electric device terminal block, a terminal surface is formed in a surface
of a case and plug-in terminal insertion holes are formed in the terminal surface.
Connection portions connected to plug-in terminals inserted into the plug-in terminal
insertion holes are provided in the case.
[0005] In the lead wire terminal block, terminal surfaces are formed in the surface of the
case in a plurality of stages and lead wire insertion holes are formed in the terminal
surface in each stage. Connection portions connected to cores of lead wires inserted
into the lead wire insertion holes are provided in the case.
[0006] In addition, relay conductive plates for electrically connecting the connection portions
of the electric device terminal block and the connection portions of the lead wire
terminal block are provided in the case.
[0007] However, for example, in an electric device connection socket including a relay with
4-pole contact points, since a large number of plug-in terminals (14 plug-in terminals
in a relay with 4-pole contact points) protrude, a large number of plug-in terminal
insertion holes and a large number of connection portions are provided in a relay
terminal block (electric device terminal block) and lead wire insertion holes and
connection portions corresponding to the number of relay terminal portions need to
be provided in a lead wire terminal block.
[0008] In general, each of the lead wire insertion holes provided in the lead wire terminal
block includes a set of two lead wire insertion holes, that is, a hole into which
a signal lead wire is inserted and a hole into which a distribution lead wire (for
a contact point with a different pole in the same socket and for a crossover wire)
is inserted.
Citation List
Patent Literature
Summary of Invention
Technical Problem
[0010] In the lead wire terminal block of the electric device connection socket including
a relay with multi-pole contact points (for example, a relay with 4-pole contact points),
a large number of lead wires, such as signal lines and distribution lines, are connected
while being closely spaced, as described above. Therefore, it is difficult to easily
check the display of symbols or characters on mark tubes attached to the ends of the
lead wires.
[0011] Accordingly, an object of the invention is to provide a lead wire terminal block
that enables a user to easily check the display of a mark tube attached to the end
of each lead wire even in a case in which a large number of lead wires are connected
and an electric device connection socket including the lead wire terminal block.
Solution to Problem
[0012] In order to achieve the object, a lead wire terminal block according to an aspect
of the invention includes a plurality of lead wire insertion holes formed in a terminal
surface of a case; and a plurality of lead wire connection portions provided in the
case, the plurality of lead wire connection portions electrically connecting cores
of lead wires inserted into the lead wire insertion holes to contact points. The plurality
of lead wire insertion holes is arranged in zigzag.
[0013] In particular, the plurality of lead wire insertion holes is formed on two reference
lines extending in parallel along the terminal surface. The lead wire insertion holes
formed on one of the two reference lines and the lead wire insertion holes formed
on the other of the two reference lines are arranged in zigzag not to be aligned in
a direction perpendicular to the reference lines.
[0014] An electric device connection socket including the lead wire terminal block according
to the aspect of the invention includes an electric device terminal block having an
electric device connection portion configured to electrically connect an electric
device such as a relay or a timer, the lead wire terminal block, and a relay conductive
member configured to electrically connect the electric device connection portion and
the lead wire connection portion.
Advantageous Effects of Invention
[0015] The lead wire terminal block and the electric device connection socket including
the lead wire terminal block according to the invention enable the user to easily
check the display of a mark tube attached to the end of each lead wire even in a case
in which a large number of lead wires are connected.
Brief Description of Drawings
[0016]
FIG. 1 is a perspective view illustrating the front of an electric device connection
socket according to a first embodiment of the invention;
FIG. 2 is a perspective view illustrating the side and back of the electric device
connection socket according to the first embodiment of the invention;
FIG. 3 is a plan view illustrating the electric device connection socket according
to the first embodiment of the invention;
FIG. 4 is a diagram illustrating the inside of the electric device connection socket
according to the first embodiment of the invention;
FIG. 5 is a perspective view illustrating a lead connection portion provided in the
electric device connection socket according to the first embodiment of the invention;
FIG. 6 is a perspective view illustrating a conductive metal part forming the lead
connection portion illustrated in FIG. 6;
FIG. 7 is a perspective view illustrating a spring member forming the lead connection
portion illustrated in FIG. 6;
FIG. 8 is a diagram illustrating the opening position of a lead wire insertion hole
and a tool insertion hole with respect to the lead wire connection portion; and
FIG. 9A is a diagram illustrating a plurality of lead wire insertion holes according
to the invention which is arranged in zigzag and FIG. 9B is a diagram illustrating
a device according to the related art in which a plurality of lead wire insertion
holes is arranged in a straight line.
Description of Embodiments
[0017] Hereinafter, a first embodiment of the invention will be described with reference
to the drawings . In the following description of the drawings, the same or similar
portions are denoted by the same or similar numerical numbers. However, it is noted
that the drawings are schematic and, for example, the relationship between a thickness
and planar dimensions and the ratio of the thicknesses of layers are different from
the actual ones. Therefore, specific thicknesses or dimensions need to be determined
in consideration of the following description. In addition, the drawings may include
portions that have different dimensional relationships and ratios.
[0018] The first embodiment which will be described below illustrates a device or a method
for embodying the technical idea of the invention. The technical idea of the invention
does not limit, for example, the materials, shapes, structures, and arrangements of
components to the following. The technical idea of the invention can be modified in
various ways within the technical scope defined by the claims.
[0019] FIG. 1 is a perspective view illustrating the front of an electric device connection
socket (hereinafter, referred to as a socket) 1 according to the first embodiment
which is formed in a rectangular parallelepiped shape in appearance. FIG. 2 is a perspective
view illustrating the side and back of the socket 1. FIG. 3 is a plan view illustrating
the socket 1. In FIGS. 1 to 3 and other drawing, a longitudinal direction of socket
is referred to as a lengthwise direction and a direction perpendicular to the lengthwise
direction is referred to as a widthwise direction.
[0020] The socket 1 includes a case 2 made of a synthetic resin and a base 3.
[0021] Rail attachment portions 4a and 4b are provided in the base 3. The rail attachment
portions 4a and 4b are members that are used to attach the socket 1 to rails provided
on a distribution board (not illustrated) so as to be detachable.
[0022] A first lead wire terminal block 5 is formed at one end of the socket 1 in the longitudinal
direction. A second lead wire terminal block 6 is formed at the other end of the socket
1 in the longitudinal direction. A relay terminal block 7 is provided at the bottom
of a concave portion that is formed between the first lead wire terminal block 5 and
the second lead wire terminal block 6.
[0023] The first lead wire terminal block 5 has first to third terminal surfaces 8A, 8B,
and 8C which are formed in a surface of the case 2 in a plurality of stages with different
heights.
[0024] In this embodiment, the socket includes a plurality of lead wire insertion holes
that are formed in a terminal surface of the case and a plurality of lead wire connection
portions that are provided in the case and electrically connect cores of the lead
wires inserted into the lead wire insertion holes to contact points . The plurality
of lead wire insertion holes are arranged in zigzag.
[0025] As illustrated in FIGS. 1 and 3, four first to fourth lead wire insertion holes L1
to L4 are formed in the first terminal surface 8A which is the lowest terminal surface
among the first to third terminal surfaces 8A, 8B, and 8C so as to be arranged in
a line in the widthwise direction. In addition, a plurality of tool insertion holes
9 corresponding to the first to fourth lead wire insertion holes L1 to L4 are formed
in the first terminal surface 8A at positions that are closer to the second terminal
surface 8B than the first to fourth lead wire insertion holes L1 to L4 so as to be
arranged in a line in the widthwise direction.
[0026] The first lead wire insertion hole L1 includes two holes, that is, a signal line
insertion hole 10 and a distribution line insertion hole 11. Similarly, each of the
second to fourth lead wire insertion holes L2 to L4 includes two holes, that is, the
signal line insertion hole 10 and the distribution line insertion hole 11. In this
embodiment, the insertion hole 10 is a signal line insertion hole and the insertion
hole 11 is a distribution line insertion hole. However, the insertion hole 10 may
be the distribution line insertion hole and the insertion hole 11 may be the signal
line insertion hole.
[0027] As illustrated in FIG. 3, the first to fourth signal line insertion holes 10 of
the first to fourth lead wire insertion holes L1 to L4 are formed on a first reference
line K1 that extends in the widthwise direction at regular intervals. The first to
fourth distribution line insertion holes 11 of the first to fourth lead wire insertion
holes are formed on a second reference line K2 that is parallel to the first reference
line K1 in the lengthwise direction and extends in the widthwise direction at regular
intervals.
[0028] The first to fourth distribution line insertion holes 11 on the second reference
line K2 are formed at positions that deviate from the first to fourth signal line
insertion holes 10 on the first reference line K1 in the widthwise direction. Therefore,
the first to fourth distribution line insertion holes 10 and the first to fourth distribution
line insertion holes 11 forming the first to fourth lead wire insertion holes L1 to
L4 are formed so as to be arranged in zigzag in the widthwise direction.
[0029] Eight tool insertion holes 9 are formed at positions that are separated from the
first to fourth distribution line insertion 10 and the first to fourth distribution
line insertion holes 11 in the lengthwise direction and are matched with the insertion
holes in the widthwise direction so as to be arranged in zigzag in the widthwise direction.
[0030] The second terminal surface 8B and the third terminal surface 8C have the same structure
as the first terminal surface 8A.
[0031] That is, four fifth to eighth lead wire insertion holes L5 to L8 are formed in the
second terminal surface 8B so as to be arranged in a line in the widthwise direction.
A plurality of tool insertion holes 9 corresponding to the fifth to eighth lead wire
insertion holes L5 to L8 are formed in the second terminal surface 8B at positions
that are closer to the third terminal surface 8C than the fifth to eighth lead wire
insertion holes L5 to L8 so as to be arranged in a line in the widthwise direction.
[0032] Each of the four fifth to eighth lead wire insertion holes L5 to L8 formed in the
second terminal surface 8B includes two holes, that is, the signal line insertion
hole 10 and the distribution line insertion hole 11. The signal line insertion holes
10 and the distribution line insertion holes 11 are formed so as to be arranged in
zigzag in the widthwise direction.
[0033] Eight tool insertion holes 9 corresponding to the fifth to eighth lead wire insertion
holes L5 to L8 are formed at positions that are separated from the fifth to eighth
distribution line insertion 10 and the eighth to eighth distribution line insertion
holes 11 in the lengthwise direction and are matched with the insertion holes in the
widthwise direction so as to be arranged in zigzag in the widthwise direction.
[0034] In addition, four ninth to twelfth lead wire insertion holes L9 to L12 are formed
in the third terminal surface 8C so as to be arranged in a line in the widthwise direction.
A plurality of tool insertion holes 9 corresponding to the ninth to twelfth lead wire
insertion holes L9 to L12 are formed in the third terminal surface 8C at positions
that are closer to the relay terminal block 7 than the ninth to twelfth lead wire
insertion holes L9 to L12 so as to be arranged in a line in the widthwise direction.
[0035] Each of the four ninth to twelfth lead wire insertion holes L9 to L12 formed in the
second terminal surface 8B includes two holes, that is, the signal line insertion
hole 10 and the distribution line insertion hole 11. The signal line insertion holes
10 and the distribution line insertion holes 11 are formed so as to be arranged in
zigzag in the widthwise direction.
[0036] Eight tool insertion holes 9 corresponding to the ninth to twelfth lead wire insertion
holes L9 to L12 are formed at positions that are separated from the ninth to twelfth
distribution line insertion 10 and the ninth to twelfth distribution line insertion
holes 11 in the lengthwise direction and are matched with the insertion holes in the
widthwise direction so as to be arranged in zigzag in the widthwise direction.
[0037] In a terminal surface 6a of the second lead wire terminal block 6 formed at the other
end of the socket 1 in the longitudinal direction, a thirteenth lead wire insertion
hole L13 and a fourteenth lead wire insertion hole L14 are formed and the tool insertion
holes 9 are formed at positions that are closer to the relay terminal block 7 than
the thirteenth and fourteenth lead wire insertion holes L13 and L14 so as to be arranged
in a line in the widthwise direction.
[0038] Each of the thirteenth lead wire insertion hole L13 and the fourteenth lead wire
insertion hole L14 includes two holes, that is, the signal line insertion hole 10
and the distribution line insertion hole 11, similarly to, for example, the first
lead wire insertion holes L1 formed in the first terminal surface 8A.
[0039] The tool insertion holes 9 are formed at positions that are separated from the signal
line insertion holes 10 and the distribution line insertion holes 11 of the thirteenth
lead wire insertion hole L13 and the fourteenth lead wire insertion hole L14 in the
lengthwise direction and are matched with the insertion holes in the widthwise direction.
[0040] An electric device terminal block that electrically connects an electric device,
such as a relay or a timer, is formed between the first lead wire terminal block 5
and the second lead wire terminal block 6. In this embodiment, the relay terminal
block 7 is formed as the electric device terminal block. Fourteen plug-in terminal
insertion holes 15 are formed in a terminal surface 7a of the relay terminal block
7.
[0041] Next, FIG. 4 illustrates the internal structure of the socket 1 from which the case
2 has been detached. A lead wire connection portion according to this embodiment includes
a conductive metal part in which a contact point is provided and a spring member biasing
a core of a lead wire to the conductive metal part.
[0042] First to twelfth lead wire connection portions H1 to H12 forming the first lead wire
terminal block 5, thirteenth and fourteenth lead wire connection portions H13 and
H14 forming the second lead wire terminal block 6, fourteen plug-in terminal connection
portions 16 forming the relay terminal block 7, and a plurality of relay conductive
plates 18a, 18b, and 18c electrically connecting the first to fourteenth lead wire
connection portions H1 to H14 and the fourteen plug-in terminal connection portions
16 are provided on the base 3.
[0043] As illustrated in FIG. 5, the first lead wire connection portion H1 includes a conductive
metal part 21 that is fixed to the base 3 and a spring member 22 that is integrally
attached to the conductive metal part 21.
[0044] As illustrated in FIG. 6, the conductive metal part 21 is a member formed by bending
a metal flat plate in a substantially cylindrical shape and includes a spring member
surface contact portion 23, a relay plate connection portion 24, a pair of spring
member locking pieces 25, a first extension portion 26, a first fixed contact point
27 which is a first contact point, a second extension portion 28, a second fixed contact
point 29 which is a second contact point, and a spring support piece 30.
[0045] That is, the relay plate connection portion 24 extends from a lower part of the spring
member surface contact portion 23 with a flat plate shape and the spring support piece
30 extends from an upper part of the spring member surface contact portion 23.
[0046] The first extension portion 26 is bent from one side edge of the spring member surface
contact portion 23 at a right angle and extends. The second extension portion 28 is
bent from the other side edge of the spring member surface contact portion 23 at a
right angle so as to be parallel to the first extension portion 26 and extends so
as to be longer than the • first extension portion 26.
[0047] The pair of spring member locking pieces 25 bent in the direction in which the spring
member locking pieces 25 become closer to each other are formed in the lower parts
of the first extension portion 26 and the second extension portion 28 which are close
to the spring member surface contact portion 23.
[0048] The first fixed contact point 27 that is bent so as to be parallel to the spring
member surface contact portion 23 is formed at the leading end of the first extension
portion 26. The second fixed contact point 29 that is bent so as to be parallel to
the first fixed contact point 27 is formed at the leading end of the second extension
portion 28.
[0049] As illustrated in FIG. 7, the spring member 22 is a member formed by bending a conductive
metal plate and includes a conductive metal part surface contact portion 31 with a
flat plate shape, a conductive metal part locking concave portion 32 that is formed
in a lower part of the conductive metal part surface contact portion 31, and first
and second elastic portions 33 and 34 that extend from an upper part of the conductive
metal part surface contact portion 31 in a strip shape and are bent substantially
in the same direction.
[0050] The first elastic portion 33 includes a protruding portion 33a that protrudes to
one surface 31a of the conductive metal part surface contact portion 31, a bent portion
33b that is bent from the protruding portion 33a at an interior angle less than 90°,
and a first movable contact 33c that linearly extends from the bent portion 33b.
[0051] The second elastic portion 34 includes a straight extension portion 34a that linearly
extends from the upper part of the conductive metal part surface contact portion 31,
a bent portion 34b that is bent from the straight extension portion 34a at an interior
angle less than 90°, and a second movable contact 34c that linearly extends from the
bent portion 34b.
[0052] In order to integrally attach the spring member 22 to the conductive metal part 21,
the conductive metal part surface contact portion 31 of the spring member 22 is inserted
into a cylindrical space of the conductive metal part 21 and the pair of spring member
locking pieces 25 of the conductive metal part 21 are locked to the conductive metal
part locking concave portions of the spring member 22 while being elastically deformed,
with the conductive metal part surface contact portion 31 coming into surface contact
with the spring member surface contact portion 23 of the conductive metal part 21.
In a state in which the spring member 22 is integrally attached to the conductive
metal part 21, the leading end of the first movable contact 33c of the first elastic
portion 33 as a first movable contact point 33d comes into contact with the first
fixed contact point 27 and the leading end of the second movable contact 34c of the
second elastic portion 34 as a second movable contact point 34d comes into contact
with the second fixed contact point 29.
[0053] The second to fourteenth lead wire connection portions H2 to 14 have the same structure
as the first lead wire connection portion H1.
[0054] FIG. 8 illustrates the opening positions of the first to fourth lead wire insertion
holes L1 to L4 and the tool insertion holes 9 formed in the first terminal surface
8A of the case 2 with respect to the first to fourth lead wire connection portions
H1 to H4 forming the first lead wire terminal block 5 in the socket 1.
[0055] The signal line insertion hole 10 of the first lead wire insertion hole L1 is open
in the vicinity of the first movable contact point 33d of the first lead wire connection
portion H1 and the distribution line insertion hole 11 of the first lead wire insertion
hole L1 is open in the vicinity of the second movable contact point 34d of the first
lead wire connection portion H1. One of two tool insertion holes 9 is open on the
base end side of the first movable contact 33c and the other tool insertion hole 9
is open on the base end side of the second movable contact 34c.
[0056] The opening positions of the second to fourth lead wire insertion holes L2 to L4
and the tool insertion holes 9 with respect to the second to fourth lead wire connection
portions H1 have the same structure as the opening positions of the first lead wire
insertion hole L1 and the tool insertion hole 9 with respect to the first lead wire
connection portion H1.
[0057] In addition, the opening positions of the fifth to twelfth lead wire insertion holes
L5 to L12 and the tool insertion holes 9 formed in the second and third terminal surfaces
8B and 8C of the case 2 with respect to the fifth to twelfth lead wire connection
portions H5 to H12 forming the first lead wire terminal block 5 have the same structure
as the opening positions of the first to fourth lead wire insertion holes L1 to L4
and the tool insertion holes 9 with respect to the first to fourth lead wire connection
portions H1 to H4 illustrated in FIG. 8, which is not illustrated in the drawings.
[0058] In the first lead wire terminal block 5 having the above-mentioned structure, signal
lines are connected to the first to twelfth lead wire connection portions H1 to H12
as follows. A tool is inserted into the tool insertion hole 9 which is open on the
base end side of the first movable contact 33c in the case 2 to elastically deform
the first elastic portion 33 such that the first movable contact point 33d of the
first movable contact 33c does not come into contact with the first fixed contact
point 27. Then, after the signal line is inserted into the signal line insertion hole
10, the elastic deformation of the first elastic portion 33 is released and the core
of the signal line is interposed between the first fixed contact point 27 and the
first movable contact point 33d of the elastically restored first movable contact
33c. In this way, the signal line is connected.
[0059] In a case in which distribution lines are connected to the first to twelfth lead
wire connection portions H1 to H12, a tool is inserted into the tool insertion hole
9 which is open on the base end side of the second movable contact 34c in the case
2 to elastically deform the second elastic portion 34 such that the second movable
contact point 34d does not come into contact with the second fixed contact point 29.
Then, after the distribution line is inserted into the distribution line insertion
hole 11, the elastic deformation of the second elastic portion 34 is released and
the core of the distribution line is interposed between the second fixed contact point
29 and the second movable contact point 34d of the elastically restored second movable
contact 34c. In this way, the distribution line is connected.
[0060] A lead wire terminal block according to the invention corresponds to the first lead
wire terminal block 5. An electric device terminal block according to the invention
corresponds to the relay terminal block 7. Two reference lines according to the invention
correspond to the first reference line K1 and the second reference line K2.
[0061] FIG. 9A is a diagram schematically illustrating the first terminal surface 8A in
a case in which signal lines 35 and distribution lines 36 are connected to the first
to fourth lead wire connection portions H1 to H4 of the first lead wire terminal block
5.
[0062] Four signal line insertion holes 10 are formed on the first reference line K1 at
regular intervals and four distribution line insertion holes 11 are formed on the
second reference line K1 at regular intervals. The eight signal line insertion holes
10 and distribution line insertion holes 11 are formed so as to be arranged in zigzag.
Therefore, a distance between the signal line insertion hole 10 and the distribution
line insertion hole 11 which are adjacent to each other can be set to D1.
[0063] FIG. 9B illustrates a lead wire terminal block according to the related art in which
a plurality of signal line insertion holes S1 and distribution line insertion holes
S2 are formed in a straight line on a reference line K3. A distance D2 between the
signal line insertion hole S1 and the distribution line insertion hole S2 which are
adjacent to each other is less than the distance D1 between the signal line insertion
hole 10 and the distribution line insertion hole 11 which are adjacent to each other
illustrated in FIG. 9A.
[0064] In many cases, mark tubes on which symbols or characters for identifying the type
of each line are displayed are attached to the ends of the signal line 35 and the
distribution line 36. In a case in which the distance between the signal line insertion
hole 10 and the distribution line insertion hole 11 which are adjacent to each other
is the distance D1 as illustrated in FIG. 9B, the signal line 35 and the distribution
line 36 to which the mark tubes are attached are connected while being closely spaced.
Therefore, it is difficult to easily check the symbol or display of the mark tube.
[0065] In contrast, in the first embodiment illustrated in FIG. 9A, a plurality of signal
line insertion holes 10 and distribution line insertion holes 11 are arranged in zigzag
and the distance (distance D1) between the signal line insertion hole 10 and the distribution
line insertion hole 11 which are adjacent to each other is sufficiently ensured. Therefore,
even in a case in which the mark tubes are attached to all of the signal lines 35
and the distribution lines 36 connected to the first lead wire terminal block 5, it
is possible to easily check the symbols or display of the mark tubes since the signal
lines 35 and the distribution lines 36 are not connected while being closely spaced.
[0066] In a case in which the signal lines 35 and the distribution lines 36 are connected
to the fifth to twelfth lead wire connection portions H5 to H12 forming the first
lead wire terminal block 5, it is possible to obtain the same effect as that in the
case in which the signal lines 35 and the distribution lines 36 are connected to the
first to fourth lead wire connection portions H1 to H4.
[0067] In a case in which the signal lines 35 and the distribution lines 36 are connected
to or disconnected from the lead wire connection portions H1 to H12, the spring member
22 is elastically deformed by the tool inserted into the tool insertion hole 9 provided
in the vicinity of the signal line insertion hole 10 and the distribution line insertion
hole 11 to temporarily release the biasing of the spring member 22 such that the first
and second movable contact points 33d and 34d can be separated from the first and
second fixed contact points 27 and 29.
[0068] In a case in which the signal lines 35 and the distribution lines 36 are connected
to the lead wire connection portions H1 to H12, after the signal line 35 and the distribution
line 36 are inserted into the signal line insertion hole 10 and the distribution line
insertion hole 11, the spring member 22 is elastically restored such that the core
of the signal line 35 is interposed between the first movable contact point 33d and
the first fixed contact point 27 and the core of the distribution line is interposed
between the second movable contact point 34d and the second fixed contact point 29.
In this way, the signal line 35 and the distribution line 36 can be connected. As
such, it is possible to facilitate an operation of connecting the signal line 35 and
the distribution line 36.
[0069] In each of the lead wire connection portions H1 to H12, the spring member 22 is integrally
attached to the conductive metal part 21. Each of the lead wire connection portions
H1 to H12 includes the first fixed contact point 27 and the first movable contact
point 33d for connecting the signal line 35 and the second fixed contact point 29
and the second movable contact point 34d for connecting the distribution line 36.
Therefore, it is possible to reduce the number of components and the cost of the device.
Industrial Applicability
[0070] As described above, the lead wire terminal block and the electric device connection
socket including the lead wire terminal block according to the invention make it possible
to easily check the display of the mark tube attached to the end of each lead wire
even in a case in which a large number of lead wires are connected.
Reference Signs List
[0071]
1: socket
2: case
3: base
4a, 4b: rail attachment portion
5: first lead wire terminal block
6: second lead wire terminal block
6a: terminal surface
7: relay terminal block
7a: terminal surface
8A: first terminal surface
8B: second terminal surface
8C: third terminal surface
9: tool insertion hole
10: signal line insertion hole
11: distribution line insertion hole
15: plug-in terminal insertion hole
16: plug-in terminal connection portion
18a, 18b, 18c: relay conductive plate
21: conductive metal part
22: spring member
23: spring member surface contact portion
24: relay plate connection portion
25: spring member locking piece
26: first extension portion
27: first fixed contact point
28: second extension portion
29: second fixed contact point
30: spring support piece
31: conductive metal part surface contact portion
32: conductive metal part locking concave portion
33: first elastic portion
33a: protruding portion
33b: bent portion
33c: first movable contact
33d: first movable contact point
34: second elastic portion
34a: straight extension portion
34b: bent portion
34c: second movable contact
34d: second movable contact point
35: signal line
36: distribution line
H1 to H14: first to fourteenth lead wire connection portions
K1: first reference line
K2: second reference line
L1 to L14: first to fourteenth lead wire insertion holes