BACKGROUND OF THE INVENTION
[0001] The present invention relates to a power breaker for interrupting a power circuit
utilizing sublimation of a gas starting agent for example, and more particularly,
to a resettable power breaker in which after a power circuit is forcibly interrupted
when abnormal conditions were encountered or a short circuit, collision of vehicle
or the like occurred, it is possible to reliably prevent the power circuit from being
energized again by impact, vibration or other external force.
[0002] Japanese Patent Application Laid-open No. H11-301376 discloses a structure in which
in a power breaker in which can forcibly interrupt a power circuit when abnormal conditions
were encountered or a short circuit, collision of vehicle or the like occurred. However,
a structure of the above-described conventional power breaker as the following problem.
That is, since there is no function for holding the shaft at the interruption position
after the shaft was slid to the interruption position to interrupt between the terminals,
there is an adverse possibility that the shaft may be returned to the initial position
by reaction force, impact, vibration caused by the projecting motion of the shaft
or by external force, and the terminals may be electrically connected to each other.
[0003] Japanese Patent Application Laid-open No. H9-251830 discloses a structure in which
in a power breaker having two terminals for making and breaking a power circuit and
capable of connecting and separating the two terminals to and from each other by sliding
movement of a shaft. In the case of a returning motion-preventing lock used in the
disclosed technique, there is a problem that although the shaft can be locked at the
interruption position, this lock can not be released to return the shaft to the initial
position.
SUMMARY OF THE INVENTION
[0004] In view of the above circumstances, it is an object of the present invention to provide
a resettable power breaker in which after a power circuit is forcibly interrupted
when abnormal conditions were encountered or a short circuit, collision of vehicle
or the like occurred, it is possible to reliably prevent the power circuit from being
energized again by impact, vibration or other external force.
[0005] To achieve the above object, according to a first aspect of the present invention,
there is provided a power breaker comprising a pair of terminals inserted in a power
circuit for connecting a battery of a vehicle and loads provided in various portions
of the vehicle, and a shaft capable of connecting and separating the terminals to
and from each other by sliding movement of the shaft, in which the shaft is slid from
an initial position where the terminals are connected to each other to an interruption
position where the terminals are separated from each other, thereby interrupting the
power circuit, wherein the shaft is provided at its one end with a returning motion-preventing
lock which jumps out from the shaft when the shaft interrupts the power circuit to
prevent the shaft from returning to the initial position.
[0006] According to the first aspect, the shaft capable of connecting and separating the
two terminals with and from each other to energize and interrupt the power circuit
is provided at its one end with a returning motion-preventing lock which jumps out
from the shaft when the shaft interrupts the power circuit to prevent the shaft from
returning to the initial position. Therefore, the shaft can be held at the interruption
position by the returning motion-preventing lock, and it is possible to reliably prevent
the power circuit from being energized again by impact, vibration or other external
force after a power circuit is forcibly interrupted when abnormal conditions were
encountered or a short circuit, collision of vehicle or the like occurred.
[0007] Accordingly, since the returning motion-preventing lock jumps out from the shaft
when the shaft interrupts the power circuit, a reset operation for returning the shaft
to its original initial position can be carried out easily.
[0008] In a second aspect of the present invention, the returning motion-preventing lock
is accommodated in a reset knob mounted to one end of the shaft together with a resilient
member, and the returning motion-preventing lock jumps out by a force of the resilient
member when the shaft interrupts the power circuit.
[0009] According to the second aspect, since the returning motion-preventing lock can easily
be accommodated in the reset knob manually, the reset operation for returning the
shaft to the original initial position can be carried out easily.
[0010] In a third aspect of the present invention, the resilient member is a torsion spring
provided in the reset knob and acting around the reset knob fulcrum.
[0011] According to the third aspect, since the torsion spring exerts a force in an opening
direction to the returning motion-preventing lock around the reset knob. Further,
since the returning motion-preventing lock can easily be accommodated in the reset
knob manually, the reset operation for returning the shaft to the original initial
position can be carried out easily.
[0012] In a fourth aspect of the present invention, the returning motion-preventing lock
is provided with a claw engaged with an apparatus body when the returning motion-preventing
lock jumps out from the shaft, thereby preventing the shaft from falling out from
the apparatus body.
[0013] According to the fourth aspect, the returning motion-preventing lock is provided
with a claw engaged with an apparatus body when the returning motion-preventing lock
jumps out from the shaft, thereby preventing the shaft from falling out from the apparatus
body. Therefore, the reset operation for returning the shaft to the original initial
position is not interrupted.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014]
Fig. 1 is a block diagram showing one example of electrical equipment system to which
a power breaker of the present invention is applied;
Fig. 2 is a flowchart showing an interrupting flow of the electrical equipment system
shown in Fig. 1;
Fig. 3 is a sectional side view of an essential portion of an embodiment of the gas-type
power breaker in its initial state before it is operated;
Fig. 4 is a sectional side view of an essential portion of the one example of the
gas-type power breaker in its interruption state after it was operated;
Fig. 5 is a detailed explanatory view of a returning motion-preventing lock; and
Fig. 6 is a detailed explanatory view for explaining a manual operation for accommodating
the returning motion-preventing lock in a reset knob.
DESCRIPTION OF PREFERRED EMBODIMENT
[0015] Fig. 1 is a block diagram showing one example of electrical equipment system to which
a power breaker of the present invention is applied. As shown in Fig. 1, in this electrical
equipment system 1, a starter 3, an alternator 4, an ignition switch (IGN.SW) 5, and
other loads such as a load 6 provided in various portions of a vehicle are connected
to a battery 2 of the vehicle through a wire harness 8 having an electric wire 7.
A power breaker 9 of the present invention is interposed in the power circuit. A number
10 represents a G-sensor (G-SSR), and a number 11 represents an air bag ECU. They
are used for operating the power breaker 9. A number 12 represents a hazard, a number
13 represents a phone (PHONE), and a number 14 represents a door lock (D/L). They
are examples of system structural articles which do not interrupt the power circuit
by the power breaker 9.
[0016] According to this electrical equipment system 1, as shown in an interruption flow
of Fig. 2, if the subject vehicle collided against an object such as another vehicle
ahead and a collision signal was output from the G-sensor (G-SSR) 10 to the air bag
ECU11, (step ST201), a circuit interrupting signal is generated in the air bag ECU11,
and this generated circuit interrupting signal is output to the power breaker 9 (step
ST202).
[0017] With this signal, the power breaker 9 can interrupt the power circuit to stop the
electric supply from the battery 2 to the various loads such as the starter 3, the
alternator 4, the ignition switch (IGN.SW) 5 (step ST203) as will be explained below
based on Figs. 3 to 6.
[0018] Figs. 3 and 4 show a structure of one embodiment of the power breaker 9 of the present
invention. Fig. 3 is a sectional side view of an essential portion of an embodiment
of the gas-type power breaker in its initial state before it is operated, and Fig.
4 is a sectional side view of an essential portion of the one example of the gas-type
power breaker in its interruption state after it was operated.
[0019] In the power breaker 9, a shaft 16 is inserted in a base body (apparatus body) 15,
and the power breaker 9 includes terminals 17a, 17b which are connected to each other
for feeding electricity from the battery 2 to each of the loads such as the starter
3 and the alternator 4.
[0020] In an initial state before the power breaker 9 is operated, the terminals 17a, 17b
are electrically connected to each other by the shaft 16. Therefore, a current of
the power circuit flows from terminal 17a → shaft 16 → terminal 17b. Since the terminals
17a, 17b are in contact with the multi-point connection spring 18 at contacts, a large
current can flow through the terminals 17a, 17b.
[0021] In this power breaker 9, a reset knob 20 is mounted to a tip end of the shaft 16
using a stopper 19, and a torsion spring 21 and a returning motion-preventing lock
22 are bent and accommodated in the reset knob 20.
[0022] The returning motion-preventing lock 22 can be rotated around a reset-knob fulcrum
20a of the reset knob 20 by a load of the torsion spring 21. Further, as shown in
Fig. 5, the returning motion-preventing lock 22 is provided with a claw 22a so that
the returning motion-preventing lock 22 will not rotate beyond a predetermined rotational
angular position to prevent the shaft 16 from falling out from the base body 15.
[0023] An ignitor 24 accommodating a gas starting agent 23 therein is mounted to a rear
end of the shaft 16. In Fig. 5, a number 25 represents a starting-agent case, a number
26 represents a nozzle, a number 27 represents a nozzle-mounting plate, a number 28
represents an O-ring, and a number 29 represents a terminal-mounting plate.
[0024] In such an assembling structure, when gas is generated by sublimation of the gas
starting agent 23, the shaft 16 and the reset knob 20 are moved by this gas pressure
to an interruption state shown in Fig. 1 in which the shaft 16 and the reset knob
20 are projected from the base body 15.
[0025] In this state, the returning motion-preventing lock 22 jumps out from inside of the
reset knob 20 firmly connected together with the shaft 16, and it is possible to prevent
the shaft 16 and the reset knob 20 from returning to the initial position.
[0026] Therefore, the shaft 16 can be held at the interruption position by the returning
motion-preventing lock 22, and it is possible to reliably prevent the power circuit
from being energized again by impact, vibration or other external force after a power
circuit is forcibly interrupted when abnormal conditions were encountered or a short
circuit, collision of vehicle or the like occurred.
[0027] The returning motion-preventing lock 22 jumps out from inside of the reset knob 20
firmly connected together with the shaft 16 by a force of the torsion spring 21 at
the time of the interrupting operation of the shaft. Therefore, as shown in Fig. 6,
the returning motion-preventing lock 22 can easily be inserted manually into the reset
knob 20 in a direction of arrow A while pushing the returning motion-preventing lock
22 in a direction of arrow B (while preventing the returning motion-preventing lock
22 from jumping out).
[0028] When the returning motion-preventing lock 22 jumps out from inside of the reset knob
20, the claw 22a provided on the returning motion-preventing lock 22 engages the base
body 15 to prevent the shaft 16 from falling out from the base body 15. Therefore,
the reset operation for returning the shaft 16 to the original initial position is
not interrupted.
[0029] Since the returning motion-preventing lock 22 can easily be accommodated in the reset
knob 20 manually and the shaft 16 can be prevented from falling out from the base
body 15 in this manner, the reset operation for returning the shaft 16 to the original
initial position can be carried out easily.
[0030] In the present invention, as a resilient member provided in the reset knob 20 mounted
to one end of the shaft 16, a compression spring or a rubber may be used instead of
the torsion spring. Any member may be used as the resilient member only if it can
reliably bias the returning motion-preventing lock outward at the time of the interrupting
operation of the shaft.
1. A power breaker comprising a pair of terminals inserted in a power circuit for connecting
a battery of a vehicle and loads provided in various portions of the vehicle, and
a shaft capable of connecting and separating said terminals to and from each other
by sliding movement of said shaft, in which said shaft is slid from an initial position
where said terminals are connected to each other to an interruption position where
said terminals are separated from each other, thereby interrupting said power circuit,
wherein
said shaft is provided at its one end with a returning motion-preventing lock which
jumps out from said shaft when said shaft interrupts said power circuit to prevent
said shaft from returning to said initial position.
2. A power breaker according to claim 1, wherein said returning motion-preventing lock
is accommodated in a reset knob mounted to one end of said shaft together with a resilient
member, and said returning motion-preventing lock jumps out by a force of said resilient
member when said shaft interrupts said power circuit.
3. A power breaker according to claim 2, wherein said resilient member is a torsion spring
biasing said returning motion-preventing lock outward.
4. A power breaker according to claim 1, wherein said returning motion-preventing lock
is provided with a claw engaged with an apparatus body when said returning motion-preventing
lock jumps out from said shaft, thereby preventing said shaft from falling Out from
said apparatus body.