Technical Field
[0001] The present invention relates to a detector base for mounting a detector for detecting
abnormalities such as fires that produce flame, smoke, and the like on a ceiling or
a wall surface, and a detecting device including the detector base and the detector
(smoke detector, heat detector, infrared detector, and the like).
Background Art
[0002] The detector is configured to be removably attached to the detector base installed
on the ceiling surface of a building or the like. The detector base is connected to
a receiver installed in a fire monitoring room, and the like via wiring called the
detector line installed above the ceiling, and the like. One detector line is connected
to multiple detector bases. Each detector base has its own fire detector attached
to it.
[0003] A conduction test is generally performed when the detector line has been installed
in the building and the detector bases have been installed, to ensure that the line
has been installed correctly. Before attaching the detector to the detector base,
conduction is maintained between positive or negative power input/output terminals
at each detector base, and the voltage or current between the positive and negative
power terminals at the detector base at the end of the line is measured with a tester.
Thereby, the conduction test of the detector line is performed.
[0004] There is conventionally disclosed an invention relating to a detector base which
is connected electrically between the terminals of the same polarity by a short-circuit
wire spring, and the short-circuit wire spring can be easily removed after the inspection
of the line is completed, in order to enable conduction between the positive or negative
pair of power input/output terminals at each detector base before the detector is
installed. (See Patent Document 1).
[0005] In addition, an invention relating to the detector base in which an arc-shaped metal
piece is provided between the terminals to be conducted, and by sliding this arc-shaped
metal piece, it is possible to electrically conduct or interrupt between a pair of
terminals is disclosed (see Patent Document 2).
Citation List
Patent Literatures
Summary of Invention
Technical Problem
[0007] The detector base of Patent Document 1 requires inserting and connecting the ends
of the short-circuit wire springs between the same polarity terminals of each detector
base during the conduction test performed after the installation of the detector line,
and removing the short-circuit wire springs after the test is completed. In the detector
base of Patent Document 2, electrical conduction and interruption are performed by
means of an arc-shaped metal piece for short-circuiting between the terminals to be
conducted, but the operation of sliding the arc-shaped metal piece must be performed
with the fingers (human hands).
[0008] Therefore, both the detector bases of the Patent Documents 1 and 2 have a problem
that it is troublesome to set up the conduction/interruption of the short-circuit
means between the specified terminals during the conduction test, and since the operator
is responsible for setting up the conduction/interruption of the short-circuit means,
there is a possibility of setting up errors.
[0009] In addition, there are, as the types of the detector, a type in which multiple detectors
are monitored as a unit for each detector line, and a type in which multiple detectors
connected to the detector line are managed individually with individual addresses.
[0010] Specifically, in the case of the detector called the conventional type, which is
used in the system that monitors multiple detectors as a unit for each detector line,
if even one detector connected to the detector line is out of the detector base, it
is desired to be detected to trigger an alarm. Therefore, as shown in FIG. 11A, during
the conduction test after the detector line has been installed, it is desirable to
set the conductive state "A" set by the short-circuit means in the detector base DB
to the interrupted state "B" by attaching of the detector, and to maintain the interrupted
state "C" even when the detector comes off.
[0011] Even if the negative power input terminal 6 and the negative power output terminal
1 are electrically interrupted in the detector base DB by the attaching of the detector,
the terminal 6 and the terminal 1 are in a conductive state via the power line inside
the detector. This allows power (electric power) to be transmitted to the adjacent
detector connected to the same detector line.
[0012] On the other hand, in the case of the detector called the analog type used in the
system where multiple detectors connected to one detector line are managed with the
individual addresses, even if the detector is removed from the detector base, the
removed detector can still be identified by the loss of communication. Therefore,
it is desirable for the detector line to remain monitored, since the other detectors
can be properly managed by the receiver connected via the detector line. Therefore,
as shown in FIG. 11B, during the conduction test after the detector line has been
installed, it is desirable to set the conductive state "A" set by the short-circuit
means in the detector base DB to the interrupted state "B" by attaching of the detector,
and switch to the conductive state "C" when the detector is removed.
[0013] However, both the detector bases of the Patent Documents 1 and 2 have a problem that
the setting of the short-circuit means is left to the operator's judgment, and there
is a possibility of setting errors in the short-circuit means when the detector comes
off.
[0014] The present invention was made in view of the above-mentioned problems, the object
of which is to provide the detector base and the detecting device that can easily
perform the setting work of conduction/interruption of the short-circuit means between
the specified terminals according to the type (type) of the detector after the conduction
test after the detector line has been installed.
[0015] Another object of the present invention is to provide the detector base and the detecting
device capable of preventing setting errors during the setting work of conduction/interruption
of the short-circuit means between the specified terminals according to the type (type)
of the detector after the conduction test after the detector line has been installed.
Solution to Problem
[0016] In order to achieve the object, this invention is a detector base to which a detector
is attachable and which includes: a bottom plate that is circularly shaped; a peripheral
wall that is provided along a periphery of the bottom plate; and multiple connection
terminals that are arranged at a predetermined interval in a circumferential direction
on the bottom plate, the detector including multiple external terminals that are able
to contact the respective multiple connection terminals, and the detector base comprising,
between two connection terminals among the multiple connection terminals, a short-circuiting
member that has, at ends, a pair of contact portions which are able to contact the
respective two connection terminals, and that is arranged to be movable back and forth
in a predetermined direction, wherein two protruding portions of different heights
are provided in the short-circuiting member, the contact portions at the ends contact
the corresponding two connection terminals when the short-circuiting member is moved
to one side of a movement range by a force acting on one protruding portion among
the two protruding portions, and at least one of the contact portions at the ends
separates from a corresponding connection terminal among the connection terminals
when the short-circuiting member is moved to the other side of the movement range
by a force acting on the other protruding portion among the two protruding portions.
[0017] According to the detector base having the above configuration, the short-circuiting
member is arranged to be movable back and forth between any two connection terminals,
so that by moving the short-circuiting member, the state between the two corresponding
connection terminals is shifted to the electrically conductive or non-conductive state.
In addition, since the short-circuiting member is provided with two protruding portions
of different heights, the mechanism for moving the short-circuiting member in both
directions and the mechanism for moving only to one side can be provided by using
these protruding portions of different heights.
[0018] Here, the short-circuiting member includes two protruding portions of different heights
from a surface of the bottom plate, and a guide structure that guides the short-circuiting
member is provided on an inner side of the peripheral wall.
[0019] According to such a configuration, since the short-circuiting member is provided
with two protruding portions of different heights from the surface of the bottom plate,
when the detector base is provided with the projection that can intersect the above
two protruding portions, it is easier to avoid interference with other parts or sections.
In addition, the guide structure allows the short-circuiting member to move stably.
[0020] In addition, the peripheral wall is an outer peripheral wall and an inner wall that
is formed with a predetermined interval on an inner side of the outer peripheral wall,
each of the multiple connection terminals is provided to extend to a vicinity of the
inner wall, and the short-circuiting member is arc-shaped, and arranged to be movable
along an inner circumferential surface of the inner wall.
[0021] According to such a configuration, the inner wall can be used to realize a guide
structure that guides and moves the short-circuiting member, and the outer peripheral
wall and inner wall can be used to configure a fitting unit with the case of the detector
that is joined to the detector base.
[0022] Furthermore, the short-circuiting member has a main body that has a strip shape,
and a slit that is elongated in a movement direction is formed in the main body, and
on the bottom plate, a locking piece that has a claw so as to be able to engage with
the slit is provided in parallel with the main body.
[0023] According to such a configuration, the locking piece prevents the short-circuiting
member from slipping out of the detector base.
[0024] Furthermore, the locking piece is formed such that the claw faces the inner circumferential
surface of the inner wall, and a protrusion that contacts the inner circumferential
surface of the inner wall is provided on a lateral surface of the short-circuiting
member.
[0025] According to such a configuration, a protrusion on the lateral surface of the short-circuiting
member pushes the short-circuiting member toward the locking piece, so that the engagement
between the slit of the short-circuiting member and the claw of the locking piece
is difficult to disengage.
[0026] In addition, a groove that is able to guide the protrusion on the lateral surface
of the short-circuiting member in a height direction of the inner wall is formed at
a predetermined position on the inner circumferential surface of the inner wall.
[0027] According to such a configuration, the short-circuiting member can be easily installed
in a predetermined location with accurate positioning.
[0028] In addition, on an inner side of the inner wall, multiple guide structures are provided
corresponding to between different connection terminals, each of the multiple guide
structures being the guide structure, and the short-circuiting member is arranged
selectively to one of the multiple guide structures.
[0029] According to such a configuration, the detector base can be commonly used for products
for which the short-circuiting member is to be arranged between two connection terminals
which is different for each of the products. Thus, it is possible to reduce costs.
[0030] In addition, a connection terminal among the multiple connection terminals is formed
of a plate-shaped conductive material, and each of the contact portions at the ends
of the short-circuiting member is formed by a pair of curved pieces that contact the
connection terminal so as to pinch the connection terminal from above and below.
[0031] According to such a configuration, the contact surface between the short-circuiting
member and the connection terminal can be increased to ensure good electrical conductive
state.
[0032] Another invention of the present application is a detecting device including: the
detector base having the configuration as described above; and a detector that is
joined to the detector base, wherein multiple external terminals and a projection
are provided on a bottom surface of a case of the detector, the multiple external
terminals being able to contact the respective multiple connection terminals, and
the projection facing the short-circuiting member, being located between the two protruding
portions, and having such a height that is able to interfere with at least one of
the two protruding portions when the detector is rotated in a state in which the detector
is fitted to the detector base.
[0033] According to the detecting device having the above configuration, by fitting the
detector to the detector base and rotating it, it is possible to move the short-circuiting
member in the desired direction to transition the state between the corresponding
two connection terminals to the conductive or non-conductive state.
Advantageous Effects of Invention
[0034] According to the detector base and the detecting device according to the present
invention, it is possible to easily perform the setting work of conduction/interruption
of the short-circuit means between the specified terminals when the conduction test
is performed after the detector line has been installed. There is also an effect that
it is possible to prevent setting errors during the setting work of conduction/interruption
of the short-circuit means between the specified terminals when the conduction test
is performed after the detector line has been installed.
Brief Description of Drawings
[0035]
FIG. 1 is a diagrammatic view showing the structure of the front side of one embodiment
of the detector base according to the present invention.
FIG. 2 is a diagrammatic view showing the structure of the back side of the detector
base of the embodiment.
FIG. 3 is a partially enlarged bottom view showing details of the first screw-insertion
slit in the detector base of the embodiment.
FIG. 4 is a partially enlarged diagrammatic view showing details of the second screw-insertion
slit of the detector base of the embodiment.
FIG. 5A is a diagrammatic view showing a specific example of a short-circuiting piece
forming the detector base of the embodiment.
FIG. 5B is a diagrammatic view of the short-circuiting piece shown in FIG. 5A, viewed
from another direction.
FIG. 6A is a partially enlarged diagrammatic view showing the state in which the short-circuiting
piece is installed in the detector base.
FIG. 6B is a partially enlarged diagrammatic view showing the state of the connection
between the short-circuiting piece and the connection terminal.
FIG. 6C is a cross-sectional main part view showing the state in which the short-circuiting
piece is installed in the detector base.
FIG. 7A is a partially enlarged diagrammatic view showing the relationship between
the short-circuiting piece and the high projection of the detector.
FIG. 7B is a partially enlarged diagrammatic view showing the relationship between
the short-circuiting piece and the high projection of the detector.
FIG. 8A is a partially enlarged diagrammatic view showing the relationship between
the short-circuiting piece and the low projection of the detector.
FIG. 8B is a partially enlarged diagrammatic view showing the relationship between
the short-circuiting piece and the low projection of the detector.
FIG. 9A is a diagrammatic view showing the structure of the bottom of the body case
of the detector.
FIG. 9B is a diagrammatic view showing the structure of the bottom of the body case
of another type of the detector.
FIG. 10A is a partially enlarged diagrammatic view showing details of the terminal
number display section on the connection terminal of the detector base of the embodiment.
FIG. 10B is a diagrammatic view of the terminal number display section shown in FIG.
10A, viewed from the opposite side.
FIG. 11A is a circuit diagram showing the transition of the state of the connection
between the terminals of the detector base in the detector line using the conventional
type of the detector.
FIG. 11B is a circuit diagram showing the transition of the state of the connection
between the terminals of the detector base in the detector line using the analog type
of the detector.
Description of Embodiments
[0036] The embodiment of the detector base according to the present invention is explained
with reference to the drawings. FIG. 1 is a diagrammatic view showing the structure
of the front side of the detector base 10 of the embodiment.
[0037] FIG. 2 is a diagrammatic view showing the structure of the back side of the detector
base 10.
[0038] The detector base 10 is generally fixed and installed on the ceiling surface of a
building with the back side facing upward and the front side facing downward. The
detector is mounted on the front side. The detector base is connected to a receiver,
not shown, that centrally manages multiple detectors in the area to be detected. When
the detector detects an event such as fire, the receiver is notified of the detection
signal from the detector via the terminals on the detector base and the wiring (the
detector line) connected to the terminals.
[0039] The detector attached to the detector base can be a thermal detector with a thermistor,
a smoke detector with a photoelectric element, a flame detector with an infrared detector,
or any other detector with any detection method.
[0040] The detector base 10 of the embodiment is made of synthetic resin and, as shown in
FIG. 1, includes: the base body 11, which has a small height and a bottomed cylindrical
shape; connection terminals 12A to 12F arranged in a radial line on the bottom plate
11a that forms a circular shape inside the base body 11; screws 13A to 13F for fixing
the connection terminals 12A to 12F on the above bottom plate 11a; and screws 14A
to 14F and safety washers 15A to 15F for electrically connecting the wiring cores
to terminals 12A to 12F.
[0041] The above connection terminals 12A to 12F each have an inverted-L shape. An insertion
hole through which the each of the above screws 13A to 13F is inserted is formed at
the intersection of the shorter side and the longer side, and the shorter side has
an insertion hole through which each of the above screws 14A to 14F is inserted.
[0042] Around the above bottom plate 11a, an outer peripheral wall 11b is provided. On the
inner side of the outer peripheral wall 11b, an inner wall 11c of the same height
is formed with a slight gap between the outer peripheral wall 11b and the inner wall
11c. The circular wall at the bottom of the case of the detector is placed between
the outer peripheral wall 11b and the inner wall 11c, so that the case of the detector
is fitted to the base body 11.
[0043] In addition, the base body 11 has arc-shaped terminal support ribs 11e1, 11e2, which
are lower in height than the above inner wall 11c, on the bottom plate 11a of the
base body 11. The connection terminals 12A to 12F are arranged so that the longer
sides of the connection terminals 12A to 12F are in contact with these terminal support
ribs 11e1, 11e2. As a result, a gap is formed between the longer sides of the connection
terminals 12A to 12F and the inner surface of the bottom plate 11a of the base body
11 so that terminals 22A to 22F (see FIG. 9) of the detector are inserted into these
gaps and contact with each other and make an electrical connection. (The above description
shows an example with six terminals 22A to 22F. However, in the case where the terminal
which is not to be used as the detector, for example, the terminal 22D is not used,
the terminal itself may not be installed).
[0044] Furthermore, as shown in FIG. 2, the bottom plate 11a of the base body 11 has, in
the center thereof, a circular opening 11f through which the wires extending from
the ceiling are passed. The bottom plate 11a also has slits 11g1, 11g2, each extending
in the radial direction of the base body across the opening 11f. The slits 11g1 and
11g2 can be used to insert the necks of two screws that have been installed in advance
with their heads facing down (to the floor) at the installation site (ceiling surface)
of the base body 11.
[0045] The slits 11g1, 11g2 are formed one step lower than the inner surface of the above
bottom plate 11a, and the width of the slits 11g1 and 11g2 is smaller than the diameter
of the head of the screws used to fasten the base body 11 to the ceiling surface and
larger than the diameter of the neck of the screws.
[0046] As shown enlarged in FIG. 3, the slit 11g1 among the slits 11g1 and 11g2 is bent
at a nearly right angle at its outer end. There, a screw insertion hole 11h is formed,
the diameter of which is slightly larger than the diameter of the head of the screw
used to fix the base body 11 to the ceiling surface.
[0047] The inner end of the other slit 11g2 is provided with a cut portion 11i forming an
entrance large enough to allow the head of the above screw to pass through, as shown
enlarged in FIG. 4. When the head of the screw is fitted to this cut portion 11i with
the top surface of the head of the screw in contact with the back surface of the bottom
plate 11a, the neck of the screw can move along the slit 11g2.
[0048] Therefore, the detector base 10 is joined to the ceiling surface so that the screw
insertion hole 11h and the entrance (cut portion 11i) are aligned with the heads of
two screws which are provided at a predetermined interval from each other with the
heads facing down at the base installation position on the ceiling surface in advance.
Then, the detector base 10 is rotated about 10 degrees around the entrance (111).
After relative movement of the screw of the screw insertion hole 11h to the slit 11g1,
the detector base 10 is moved in the direction of the extension of the slits 11g1,
11g2. Then, by the relative slide of the necks of the above two screws along the slits
11g1 and 11g2, the detector base 10 is then set in the normal position. By turning
and tightening the two screws in this state, the detector base 10 is fixed to the
ceiling surface.
[0049] As described above, the detector base 10 of the embodiment is configured to be installed
in a predetermined position by attaching, in advance, two screws at a predetermined
interval to the base installation position on the ceiling surface, and the like, and
aligning the screw insertion holes 11h and the entrance (11i) of the detector base
10 with these screws and sliding and then tightening the screws. This improves work
efficiency compared to the installation method in which the detector base 10 is first
joined to the base installation position and the screws are later tightened through
the screw holes in the detector base. Also, when the detector base 10 needs to be
replaced, the detector base 10 can be removed to attach another detector base simply
by loosening the screws, without the need to remove them. This means that the work
can be completed in a short period of time.
[0050] Furthermore, as shown in FIG. 1, on the inner circumferential surface of the inner
wall 11c between the above connection terminals 12E and 12F, an arc-shaped short-circuiting
piece 16 for electrical connection between terminals 12E and 12F is arranged so as
to be slidable along the inner circumferential surface. The above short-circuiting
piece 16 is formed by punching and bending a plate-shaped metal material such as used
for plate springs.
[0051] Though the detector base 10 of the embodiment is not especially limited, the inner
circumferential surface of the inner wall 11c between the connection terminals 12F
and 12A, in addition to between the connection terminals 12E and 12F, is also provided
with a structure to allow the above-mentioned short-circuiting piece 16 to be slidably
arranged along the circumferential surface. In the embodiment, when the short-circuiting
piece 16 is arranged between the connection terminals 12F and 12A, the short-circuiting
piece 16 is not arranged between the connection terminals 12E and 12F.
[0052] FIG. 5A and FIG. 5B show the detailed shape of the above short-circuiting piece 16.
FIG. 6A and FIG. 6B show the details of the state in which this short-circuiting piece
16 is placed on the inner circumference of the inner wall 11c and the joining state
of the connection terminals 12E and 12F with the short-circuiting piece 16. FIG. 6C
also shows an example of a slip-off stopping structure of the short-circuiting piece
16.
[0053] As shown in FIGS. 5, the short-circuiting piece 16 includes: a horizontal plate-shaped
main body 16a; contact portions 16b provided at both ends of the main body 16a; a
bent piece 16c that protrudes upward from a position a little further away from the
center of the upper side of the main body 16a, and then bends inward; and a bent piece
16d that protrudes upward from a position a little further away to the opposite side
of the above from the center of the upper side of the main body 16a, and then bends
inward, and furthermore has the tip bent downward. The bent piece 16d is formed to
be lower in height than the bent piece 16c.
[0054] The main body 16a of the short-circuiting piece 16 has a strip shape, and this main
body 16a has a slit 16e, which is elongated in the movement direction, to which the
slip-off stopping piece 11j (see FIG. 6C) described below engages. The contact portion
16b at each end of the main body 16a is a pair of elongated plate-shaped pieces extending
toward both sides, curved so that portions are closer to each other. The interval
between the closest portions is formed to be smaller than the thickness of the connection
terminals 12A to 12F. When the short-circuiting piece 16 is moved in the longitudinal
direction, the connection terminals 12A to 12F can pass between the contact portions
16b from one side to the other.
[0055] Furthermore, a pair of punched, deformed and machined protrusions 16f are formed
on the outer surfaces of both ends of the main body 16a.
[0056] FIG. 6A shows a state in which the short-circuiting piece 16 is arranged between
the two connection terminals 12E and 12F. In the state shown in FIG. 6A, the contact
portion 16b of the short-circuiting piece 16 is off the connection terminal 12E and
is not in contact with the connection terminal 12E, so the area between the connection
terminals 12E and 12F is electrically non-conductive. When the short-circuiting piece
16 is slid toward the connection terminal 12E from this state, as shown in FIG. 6B,
the contact portions 16b at both ends of the short-circuiting piece 16 pinch the tips
of the connection terminals 12E and 12F from above and below, so that the area between
the connection terminals 12E and 12F becomes electrically conductive.
[0057] The contact portions 16b at both ends of the short-circuiting piece 16 slide in contact
with the surfaces of the connection terminals 12E and 12F, which can be expected to
clean the contact surfaces and maintain good electrical contact.
[0058] Between the connection terminals 12E and 12F as shown in FIG. 6A, and between the
inner wall 11c and the terminal support ribs 11e as shown in FIG. 6C, the detector
base 10 has a slip-off stopping piece 11j with an outward-facing claw at the upper
end, which rises upward from the bottom plate 11a. The short-circuiting piece 16 is
then located along the inner circumferential surface of the inner wall 11c with the
central slit 16e engaging with the claw of the slip-off stopping piece 11j.
[0059] Therefore, the short-circuiting piece 16 is held in place so that it does not fall
out of the detector base 10 even if the detector base 10 is turned upside down or
subjected to impact. Furthermore, a pair of protrusions 16f formed on the outer surfaces
of both ends of the main body 16a presses the entire short-circuiting piece 16 inwardly,
so that the slip-off stopping piece 11j is firmly inserted into the slit 16e, making
the engagement between the short-circuiting piece 16 and the slip-off stopping piece
11j difficult to disengage.
[0060] In addition, in the embodiment, as shown in FIG. 6A, a guiding groove 11k, which
has a width approximately the same as the diameter of the aforementioned protrusion
16f and which becomes wider as it moves upward is provided at a predetermined site
of the inner circumferential surface of the inner wall 11c. Thus, when the short-circuiting
piece 16 is inserted on the inner side of the inner wall 11c, the protrusion 16f is
aligned with the upper portion of the guiding groove 11k and pushed downward, and
thereby aligned with the predetermined mounting position and stored. In other words,
the protrusion 16f has the function of guiding the short-circuiting piece 16 during
insertion, and the function of pressing the short-circuiting piece 16 inward after
insertion.
[0061] Furthermore, at the portion of the inner circumferential surface of the inner wall
11c that is facing the aforementioned slip-off stopping piece 11j, a groove 11m slightly
wider than the width of the slip-off stopping piece 11j is formed. This groove 11m
allows the tip of a tool such as a flat screwdriver to be inserted between the short-circuiting
piece 16 and the slip-off stopping piece 11j, hook it to the slit 16e, and lift it
up to easily remove the short-circuiting piece 16 from the inner side of the inner
wall 11c. Furthermore, although not shown in the figure, a guide groove where the
lower edge of the short-circuiting piece 16 engages is formed with a predetermined
length at the base of the inner wall 11c, and this guide groove is configured to limit
the slidable range of the short-circuiting piece 16.
[0062] Next, the function of the bent pieces 16c and 16d on the short-circuiting piece 16
and the reason for changing the height of the bent pieces 16c and 16d will be explained.
[0063] FIG. 7A and FIG. 7B show the configuration of the bent pieces 16c and 16d of the
short-circuiting piece 16 and the bottom surface of the detector. In FIG. 7A and FIG.
7B, the sign 21 indicates a part of the circularly shaped bottom plate of the body
case of the detector that is joined to the detector base of the embodiment. The bottom
plate 21 has a projection 21a that is in an inverted L-shape in a side view on the
part of the bottom plate 21 facing the short-circuiting piece 16 and located between
the bent pieces 16c and 16d of the short-circuiting piece 16 when the body case of
the detector is joined to the detector base.
[0064] The height of the projection 21a is set such that its tip (lower end in FIG. 7A and
FIG. 7B) reaches the position where the tip intersects with the bent pieces 16c and
16d of the short-circuiting piece 16. Thus, in FIG. 7A, when the bottom plate 21 is
moved (rotated) to the right, the side of the tip of the projection 21a contacts the
bent piece 16c, and the short-circuiting piece 16 moves together. On the other hand,
when the bottom plate 21 is moved (rotated) to the left, as shown in FIG. 7B, the
side of the tip of the projection 21a contacts the bent piece 16d and the short-circuiting
piece 16 moves together.
[0065] The reason why the projection 21a is shaped in the inverted L-shape is to increase
the strength against bending stress generated at the base of the projection 21a when
a force acts on the tip of the projection 21a. Therefore, the shape of the projection
21a is not limited to the inverted L-shape viewed in a side view, but may be rectangular
with the tip having the same width as that of the base, that is, the entire projection
may be cuboid.
[0066] In the embodiment, the body case of the detector is rotated by a predetermined angle
(approximately 10°) in a circumferential direction when the body case of the detector
is joined to the detector base 10 and when the body case of the detector is separated
from the detector base 10. Therefore, in order to join the body case of the detector
to the detector base 10, when the body case is rotated after being aligned with and
fitted to the detector base 10 at a predetermined angle, the short-circuiting piece
16 is moved by the rotation operation. Then, as shown in FIG. 6A, the contact portions
16b of the short-circuiting piece 16 come off the connection terminals 12E and 12F,
which sets the electrically non-conductive state between the connection terminals
12E and 12F.
[0067] On the other hand, when the body case of the detector is rotated in the opposite
direction to the above in order to separate the body case of the detector from the
detector base 10, the short-circuiting piece 16 is moved by the rotation operation.
Then, as shown in FIG. 6B, the contact portions 16b of the short-circuiting piece
16 pinch and contact the connection terminals 12E and 12F, which sets the electrically
conductive state between the connection terminals 12E and 12F. By reversing the positional
relationship between the bent pieces 16c and 16d, the direction of the rotation operation
of the body case of the detector and setting of the non-conductive state or the conductive
state can be the opposite of the above.
[0068] FIG. 8A and FIG. 8B show the relationship between the projection 21a and the bent
pieces 16c and 16d of the short-circuiting piece 16 in the case where the height of
the projection 21a is set to be lower than FIG. 7A and FIG. 7B, and to be such height
that the tip of the projection 21a intersects the bent piece 16c of the short-circuiting
piece 16 but does not intersect the bent piece 16d.
[0069] In the case where the height of the projection 21a is set as described above, when
the body case of the detector is rotated relative to the detector base 10 in order
to join the body case of the detector to the detector base 10, the rotation operation
causes the projection 21a to contact the bent piece 16c and the short-circuiting piece
16 is moved together, as shown in FIG. 8A. Then, as shown in FIG. 6A, the contact
portions 16b of the short-circuiting piece 16 come off the connection terminals 12E
and 12F, which sets the electrically non-conductive state between the connection terminals
12E and 12F.
[0070] On the other hand, when the body case of the detector is rotated in the opposite
direction to the above in order to separate the body case of the detector from the
detector base 10, the short-circuiting piece 16 is moved by the rotation operation.
As shown in FIG. 8B, the projection 21a does not contact the bent piece 16d and passes
over it, and the short-circuiting piece 16 is not moved. Therefore, the contact portions
16b of the short-circuiting piece 16 remain off the connection terminals 12E and 12F,
maintaining the electrically non-conductive state between the connection terminals
12E and 12F.
[0071] Since the detector base 10 of the embodiment has the above functions, there is an
advantage that the electrical connection (conductive or non-conductive state) between
the connection terminals 12E and 12F after the detector has been removed from the
detector base 10 can be changed by selecting and forming the high projection 21a or
the low projection 21a at the bottom of the body case of the detector according to
the type (type) of the detector.
[0072] FIG. 9A shows the configuration of the bottom of the body case of the detector, which
is called the conventional type, which is used in the system in which multiple detectors
are monitored as a unit for each detector line. FIG. 9B shows the configuration of
the bottom of the body case of the detector called the analog type, which is used
in the system in which multiple detectors connected to one detector line are managed
with individual addresses.
[0073] As shown in FIG. 9A and FIG. 9B, respectively, the bottom plate 21 of the body case
20 of the detector has external terminals 22A to 22F connected to the connection terminals
12A to 12F provided on the detector base 10 of the embodiment. The external terminals
22A to 22F are each provided with an inner terminal and an outer terminal having contact
pieces that are bent in a direction getting closer to each other. The contact pieces
are arranged so that they overlap each other, and inserting the connection terminals
12E to 12F of the detector base 10 between the contact pieces of the inner and outer
terminals makes the electrical connection between the terminals of the detector and
their corresponding terminals of the detector base.
[0074] In addition, a peripheral wall portion 23 that enters the gap between the outer peripheral
wall 11b and the inner wall 11c of the circumferential edge of the detector base 10
is provided in the periphery of the bottom plate 21. By fitting this peripheral wall
portion 23 to the gap between the outer peripheral wall 11b and the inner wall 11c
of the detector base 10 and rotating it, the external terminals 22A to 22F enter between
the connection terminals 12E to 12F and the bottom plate 11a. Thereby, the detector
is joined to the detector base, while making electrical connection between the corresponding
terminals.
[0075] In the detector base 10 to which the analog type detector of FIG. 9B is joined, as
shown in FIG. 1, the short-circuiting piece 16 is arranged between the connection
terminals 12E and 12F. In the detector base 10 to which the conventional type detector
of FIG. 9A is joined, the short-circuiting piece 16 is arranged between the connection
terminals 12F and 12A in FIG. 1.
[0076] The bottom plate 21 of the body case 20 shown in FIG. 9A has the low projection 21a
in the vicinity of the external terminal 22A (first terminal). The bottom plate 21
of the body case 20 shown in FIG. 9B is provided with the high projection 21a in the
vicinity of the external terminal 22F (sixth terminal) . Therefore, even if any of
the detectors is joined to the detector base 10, when the body case 20 of the detector
is turned for joining, the contact portion 16b, as shown in FIG. 6A, comes off the
connection terminals 12F, 12A or 12E, 12F, making the electrically non-conductive
state between the connection terminals 12F and 12A or between 12E and 12F.
[0077] In the state in which this detector is joined to the detector base 10, the wiring
in the detector makes the connection, and thus there is no disconnection as the detector
line.
[0078] In separating the detector from the detector base 10, when the detector (conventional
type detector) shown in FIG. 9A, which is provided with the low projection 21a, is
rotated to separate from the detector base 10, the projection 21a passes over the
bent piece 16d without contacting it. Thus, the short-circuiting piece 16 is not moved
and the contact portions 16b of the short-circuiting piece 16 remain off the connection
terminals 12F and 12A, which maintains the electrically non-conductive state between
the connection terminals 12F and 12A.
[0079] In the detector (conventional type detector) shown in FIG. 9A, the connection terminal
12F is the negative power input terminal, and the connection terminal 12A is the negative
power output terminal. Therefore, when the electrically non-conductive state is made
between the connection terminals 12F and 12A, the detector can be found to be off
(the detector line is disconnected) by measuring the voltage of the line to which
the detector base 10 is connected.
[0080] On the other hand, when the detector (analog type detector) shown in FIG. 9B, which
is provided with the high projection 21a, is rotated to separate from the detector
base 10, the projection 21a contacts the bent piece 16d and moves the short-circuiting
piece 16. Thus, the contact portions 16b of the short-circuiting piece 16 contact
the connection terminals 12E and 12F, returning to the electrically conductive state
between the connection terminals 12E and 12F.
[0081] In the detector (analog type detector) shown in FIG. 9B, the connection terminal
12F is the negative power input terminal, and the connection terminal 12E is the negative
power output terminal. Therefore, by making the electrically conductive state between
the connection terminals 12E and 12F, power is transmitted to other adjacent detectors.
Even if any of the detectors is removed from the detector base 10, the remaining detectors
operate normally, and when an abnormality is detected, the receiver can detect the
occurrence of the abnormality via the detector line.
[0082] The following List 1 and List 2 respectively show examples of applications for the
connection terminals 12B to 12E or 12A to 12D, which are other than the connection
terminals 12F and 12A or 12E and 12F which are used as the negative power input terminal
and the negative power output terminal. Among them, the List 1 shows an example of
terminal usage for the conventional type detector that uses the connection terminals
12F and 12A as the negative power input terminal and the negative power output terminal.
The List 2 shows an example of terminal usage for the analog type detector that uses
the connection terminals 12E and 12F as the negative power input terminal and the
negative power output terminal.
List 1 (Example of use of conventional type detector)
[0083]
Terminal 1: Negative (-) power output terminal
Terminal 2: Not used
Terminal 3: Positive (+) power input/output terminal
Terminal 4: Not used
Terminal 5: External indicator light control terminal
Terminal 6: Negative (-) power input terminal
List 2 (Example of use of analog type detector)
[0084]
Terminal 1: Positive (+) power input/output terminal
Terminal 2: Terminal for relay control
Terminal 3: External indicator light control terminal
Terminal 4: Not used
Terminal 5: Negative (-) power output terminal
Terminal 6: Negative (-) power input terminal
[0085] The examples of use shown in the above lists are examples and are not limited to
these.
[0086] For example, the number of terminals for the detector and the detector base may be
different.
[0087] Specifically, in the above List 2 (example of use of the analog type detector), the
terminal 4 of the detector is not used and no terminal metal fittings are provided,
thereby reducing the number of parts.
[0088] As explained above, according to the detecting device including the detector base
10 and the detector having the projection 21a in the embodiment, the height of the
projection 21a provided on the bottom plate 21 of the detector is changed according
to the type (type) of the detector. This difference in the height of the projection
21a corresponding to the type (type) of the detector enables setting of the electrical
conduction between the pair of negative power input/output terminals (same polarity
terminals) of the detector base 10 when the detector is removed from the detector
base 10, to conductive or non-conductive in conjunction with the removal of the detector.
[0089] By providing, on the detector base 10, multiple locations where the short-circuiting
piece 16 can be installed, it is possible to realize the common use of parts and cost
reduction, for the detector base used in the detection system to which different types
(types) of detectors are connected. Furthermore, by not providing the short-circuiting
piece 16 in the detector base, the detector base can also be used to connect the detector
that does not have the projection 21a.
[0090] FIG. 10A and FIG. 10B show a specific example of the terminal number display section
on the base body 11 of the detector base 10 in the embodiment.
[0091] In the detector base of the embodiment, the numbers representing the terminal numbers
are marked near the connection terminals 12A to 12F on the bottom plate 11a of the
base body 11 as outline numbers that penetrate through the bottom plate 11a. FIG.
10A shows the terminal number "2", among the terminal numbers, marked near the connection
terminal 12B. As shown in the figure, the outline number representing the terminal
number is formed on the step 11n provided on the bottom plate 11a.
[0092] Some conventional products also have numbers representing terminal numbers in the
vicinity of connection terminals 12A to 12F, but these are generally marked as embossed
numbers. Such embossed numbers have the disadvantage that they are difficult to read
because they are the same color as the base body. It is possible to color the surface
of the embossed numbers in colors different from the color of the base body. However,
there is a problem that the cost increases because of the additional process. On the
other hand, if the numbers are written as outline numbers as described above, the
numbers can be formed at the same time as forming the detector base with synthetic
resin, thus reducing the cost.
[0093] FIG. 10A represents the lower side surface of the detector base when it is installed
on the ceiling surface. If the numbers representing the terminal numbers are outline
numbers that penetrate the bottom plate 11a, there is a possibility that water may
flow down from the part of the outline numbers to the detector below and degrade the
function of the detector in the case where water from condensation enters the upper
side of the base body 11 through the ceiling surface. Moreover, if the bottom plate
11a is simply provided with the outline numbers, the area where the water drops will
fall is not stable.
[0094] On the other hand, as described above, when the outline numbers representing the
terminal numbers are formed on the steps 11n, it is possible to limit the point where
water flows down to the detector, to the edges of the steps 11n. Therefore, for example,
drainage holes can be provided in the parts of the case of the detector corresponding
to the steps 11n to allow the water that has entered to drain out quickly, thereby
preventing the detector from deteriorating its function.
[0095] Furthermore, in the detector base of the embodiment, as shown in FIG. 10B which represents
the opposite side of FIG. 10A of the base body 11, the rib 11p is formed around the
outline number. Thus, it is possible to stop, with the rib 11p, water entering the
upper side of the base body 11 from the ceiling and prevent water from flowing down
from the penetration area of the outline numbers to the detector below.
[0096] The present invention has been described based on the embodiment. However, the present
invention is not limited to the above embodiment, and can be modified to the extent
not to depart from the gist thereof. For example, the above embodiment shows the detector
base with six connection terminals, but the number of connection terminals is not
limited to six.
[0097] Also, in the above embodiment, when setting the non-conductive state between a pair
of negative power input/output terminals (same polarity terminals), the contact portions
16b at both ends of the short-circuiting piece 16 separate from the corresponding
connection terminals almost at the same time. However, only one of the contact portions
16b may separate from the corresponding connection terminal.
[0098] Furthermore, in the above embodiment, the short-circuiting piece 16 is configured
to move along the inner circumferential surface of the inner wall 11c of the base
body 11. However, it is also possible to configure the short-circuiting piece 16 to
move linearly by providing a guide member for the short-circuiting piece 16 in the
base body 11 or by other means.
[0099] In the above embodiment, the short-circuiting piece 16 is provided with, on the upper
part, the bent pieces 16c and 16d of different heights. However, the short-circuiting
piece 16 may have, on the lateral surface, two bent pieces of different heights in
the horizontal direction, and the body case of the detector may be provided with the
projection 21a of the length different in the horizontal direction that can intersect
at least one of the above bent pieces.
[0100] In addition, the above embodiment shows the double-walled structure with the outer
peripheral wall and the inner wall along the periphery of the bottom plate of the
detector base, but a single peripheral wall may be formed.
Industrial Applicability
[0101] The present invention is not limited to the detector for fire detecting, but also
can be used for the detector base and the detecting device for attaching, to buildings,
detectors that detect harmful gases and other detectors.
Reference Signs List
[0102]
10 detector base
11 base body
11a bottom plate
11b outer peripheral wall
11c inner wall
11e terminal support rib
11j locking piece
12A to 12F connection terminals
13A to 13F screws for fixing
14A to 14F screws for wiring connection
15A to 15F safety washers
16 short-circuiting piece
16a main body
16b contact portion
16c bent piece
16d bent piece
16e slit for guide
16f protrusion
20 body case of detector
21 bottom plate
21a projection
22A to 22F external terminals
23 peripheral wall portion