JP2016170127A - Current detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a current detection device that allows for accurately and easily calibrating a detection element after being assembled using a simple configuration.SOLUTION: A current detection device 1 includes; a housing 10 for a bus-bar 30 to be inserted; a mounted circuit board 40 having a detection element 42 for detecting magnetic flux induced by a current flow through the bus-bar 30; a magnetic shield plate 50 that covers the mounted circuit board 40; a shield plate retainer 60 that pressingly secures the mounted circuit board 40 and the shield plate 50 in the housing 10, and a cover 70 that accommodates the mounted circuit board 40, shield plate 50, and shield plate retainer 60. The mounted circuit board 40 has calibration terminals 44, and the shield plate 50 and shield plate retainer 60 are assembled into the housing 10 in such a way that the calibration terminals 44 are exposed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a current detection device that detects a current flowing in a bus bar.

  Conventionally, a current detection device for detecting a current value flowing between a battery and various auxiliary machines by detecting a magnetic flux generated from a current flowing in a harness connected to a battery of an electric vehicle or the like has been known. (For example, refer to Patent Document 1). This current detection device has, for example, a structure in which a mounting board for a detection element is installed in a housing so that the detection element and the bus bar face each other, and a magnetic shield is disposed so as to enclose the detection element and the bus bar. .

  To fix the magnetic shield to the housing, for example, the convex part provided on the fixing base located above the bus bar is fitted into the hole provided in the magnetic shield, and the tip of the convex part is melted by heat. This is done by heat caulking the magnetic shield.

JP 2010-223868 A

  However, the current detection device disclosed in Patent Document 1 has a structure in which the magnetic shield is fixed to the housing by heat caulking and is stored in a proper assembly position. Therefore, detection is performed using a jig or a cover before the device is completely assembled. It was necessary to formally assemble each part after the device was calibrated. For this reason, if there is an error in the assembly position accuracy of each part during calibration and during complete assembly, the detection performance during calibration may not be able to be demonstrated as the detection performance during complete assembly. was there.

  An object of the present invention is to provide a current detection apparatus that can solve the above-described problems caused by the prior art and can accurately and easily perform calibration of a detection element after assembly with a simple configuration.

  A current detection device according to the present invention includes a housing in which a bus bar is mounted, a detection element that detects a magnetic flux generated when a current flows through the bus bar, and a substrate on which the detection element is mounted. A mounting board mounted on the housing so as to be disposed in the vicinity of the bus bar, a shield plate for magnetic shield covering the mounting board, and the mounting board and the shielding plate are pressed and fixed in the housing. A shielding plate press, and a mounting board, the shielding plate, and a cover that accommodates the shielding plate press, the mounting substrate has a connection for calibration, and the shielding plate and the shielding plate press are It is assembled to the housing in a state where the calibration connecting portion is exposed.

  According to the current detection device of the present invention, the mounting board and the shielding plate are fixed by fitting the shielding plate presser into the housing, the calibration is performed before the cover is attached, and the cover is assembled after completion. The terminal used in can be covered.

  In the present invention, it is preferable to provide a pressing protrusion on the shielding plate side of the shielding plate presser. Thereby, it is possible to fix the mounting substrate and the shielding plate while pressing them.

  The shield plate presser can be assembled to the housing so as to be rotatable about one end as an axis, and can be provided with a locking portion for the housing at the other end. As a result, the shield plate presser can be easily fixed to the housing.

  Further, the shielding plate includes a main body formed in a rectangular shape, and a projecting portion standing vertically from an end portion of the main body, and the projecting portion is fitted to a groove portion provided in the housing. Can be formed. Thereby, the said shielding board can be easily positioned in a housing.

  Preferably, the housing has a support surface for supporting the mounting substrate, and a protrusion for positioning the mounting substrate in a planar direction is provided on the support surface. Thereby, the mounting substrate can be easily positioned on the housing.

  According to the present invention, calibration of a detection element after assembly can be performed accurately and easily with a simple configuration.

It is a disassembled perspective view which shows the electric current detection apparatus which concerns on one Embodiment of this invention. It is a perspective view which shows the board | substrate accommodating part of the same electric current detection apparatus. It is a perspective view which shows the structure of the electric current detection apparatus before attaching a shielding board presser. It is a perspective view which shows the structure of the electric current detection apparatus after attaching the shielding board presser. It is a perspective view which shows the electric current detection apparatus after cover attachment. It is a top view by the side of the connector part of an electric current detection apparatus. It is A-A 'sectional drawing of FIG.

  Hereinafter, a current detection device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an exploded perspective view showing a current detection device according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a substrate housing portion of the current detection device. 3 is a perspective view showing the current detection device before attaching the shield plate press, FIG. 4 after attaching the shield plate press, and FIG. 5 after mounting the cover. 6 is a top view of the connector side of the current detection device, and FIG. 7 is a cross-sectional view taken along the line A-A ′ of FIG. 6.

  The current detection device 1 according to the present embodiment is installed in a vehicle such as an electric vehicle, for example. The current detection device 1 is mounted on the bus bar 30, and from a power source (not shown) such as a battery connected to one connection hole 31 of the bus bar 30, an auxiliary machine (not shown) connected to the other connection hole 31. ) Is detected.

  As shown in FIG. 1, the current detection device 1 according to the present embodiment includes a housing 10 that houses a part of the bus bar 30, a shielding plate 20, and a hole that detects a magnetic flux generated when a current flows through the bus bar 30. A mounting substrate 40 including a detection element such as an element, a shielding plate 50, a shielding plate presser 60, and a cover 70 are provided.

(Housing 10)
The housing 10 is made of a resin molded member integrally molded with nonmagnetic and nonconductive synthetic resin or the like. The housing 10 has a main body 11, a rectangular through-hole-shaped housing 12 that houses a part of the bus bar 30 (that is, the central portion), and one side of the main body 11 (for example, the upper side in FIG. 1). A connector portion 13 that protrudes in a rectangular shape and holds a connection terminal for connecting to another terminal inside, and stands from the end of the body portion 11 to the other side (for example, the lower side in FIG. 1) And a substrate housing portion 16 formed in a region surrounded by the side wall portion 14.

  The substrate housing portion 16 is formed in a concave shape such that the upper side in FIG. 2 is open, and is configured to be closed by covering the cover 70. In the substrate housing portion 16, on the inner side of the side wall portion 14, a support surface 11 a that supports the substrate body 41 of the mounting substrate 40, a plurality of positioning protrusions 15 for positioning the substrate body 41 in the planar direction, A recess 16 a that accommodates the detection element 42 of the mounting substrate 40, a positioning groove 17 for positioning the shielding plate 50, and an opening 13 a that communicates with the connector portion 13 are formed. The side wall 14 of the housing 10 is provided with a hinge (female) 18 and a lock claw 19 for fixing the shielding plate presser 60, and lock claws 14a and 14b for fixing the cover 70.

(Shielding plate 20)
As shown in FIG. 1, the shielding plate 20 includes a shielding plate body 21 formed in a rectangular shape, and a side wall portion 22 erected in a vertical direction from the short side end of the shielding plate body 21.
The shielding plate 20 is opposed to the shielding plate 50 described later, with the bus bar 30 mounted on the housing 10 and the mounting substrate 40 interposed therebetween. The shielding plates 20 and 50 absorb the magnetism, thereby shielding the magnetic propagation from the outside to the bus bar 30 and the mounting substrate 40 disposed inside the shielding plates 20 and 50. The intensity of the magnetic field propagating inside is suppressed.

(Mounting board 40)
The mounting board 40 includes a board main body 41 and a detection element 42 such as a Hall element that detects a magnetic flux that is mounted on the board main body 41 and that is generated when a current flows through the bus bar 30 attached to the housing 10. Yes.

  The mounting substrate 40 is mounted in the housing 10 so that the detection element 42 is disposed in the vicinity of the bus bar 30 mounted on the housing 10. That is, the substrate main body 41 is supported and fixed to the support surface 11a while being positioned in the housing 10 by the plurality of positioning convex portions 15 shown in FIG. 2, and the detection element 42 of the mounting substrate 40 is accommodated in the concave portion 16a.

  The board body 41 is connected to a connection terminal 45 extending from the connector part 13 and a terminal connection part 43 connected by soldering, etc., and an inspection device (not shown) and a calibration device when the detection element 42 is calibrated. And a calibration connection portion 44 connected via a terminal 46.

(Shield plate 50)
The shielding plate 50 includes a shielding plate body 51 formed in a rectangular shape, and a protruding portion 52 erected in the vertical direction from the long side end of the shielding plate body 51.
The shielding plate 50 is disposed so as to face the shielding plate 20 with the bus bar 30 and the mounting substrate 40 mounted on the housing 10 interposed therebetween. The shielding plates 20 and 50 absorb the magnetism, thereby shielding the magnetic propagation from the outside to the bus bar 30 and the mounting substrate 40 disposed inside the shielding plates 20 and 50. The intensity of the magnetic field propagating inside is suppressed.

(Shield plate presser 60)
The shield plate presser 60 is for fixing the shield plate 50 and the mounting substrate 40 to the housing 10 while pressing, and is provided at one end on the short side of the presser body 61 formed in a belt shape. And a locking end 63 provided at the other end. Further, the shaft portion 62 is provided with a hinge (male) 62 a that fits with the hinge (female) 18 of the housing 10, and the locking end 63 has a lock hole 63 a that is locked by the lock claw 19 of the housing 10. Is formed. A plurality of bosses 64 for pressing the shielding plate 50 and the mounting substrate 40 are provided on one side of the presser body 61.

(Cover 70)
The cover 70 is made of a resin molded member integrally molded with a nonmagnetic and nonconductive synthetic resin or the like, and is attached to the housing 10 so as to close the substrate housing portion 16.
The cover 70 includes a rectangular base portion 71, a side wall portion 72 standing vertically from the short side end portion of the substrate portion 71, and a side wall standing vertically from the long side end portion of the substrate portion 71. Part 73. Further, the side wall 72 is formed with lock holes 72 a and 72 b that engage with the lock claws 14 a and 14 b of the side wall 14 of the housing 10, respectively.

  The cover 70 is fixed to the housing 10 by engaging the lock claws 14 a and 14 b formed on the side wall 14 of the housing 10 with the lock holes 72 a and 72 b of the cover 70, respectively. When the cover 70 is fixed to the housing 10, the mounting substrate 40, the shielding plate 50, and the shielding plate presser 60 are sandwiched between the support surface 11 a of the housing 10 and the base portion 71.

(Assembly method)
Next, a method for assembling the current detection device 1 according to this embodiment will be described.

(A) First, the mounting substrate 40 on which the detection element 42 is mounted on the substrate body 41 is arranged so that the detection element 42 faces the bus bar 30 side. Specifically, the substrate body 41 is supported and fixed to the support surface 11a while being positioned by the plurality of positioning convex portions 15 in the substrate housing portion 16 of the housing 10, and the detection element 42 of the mounting substrate 40 is placed in the recess 16a. Accommodate. The terminal connection unit 43 performs solder connection of the connection terminal 45, and the calibration connection unit 44 performs solder connection of the calibration terminal 46.

(B) On the other hand, the bus bar 30 is inserted into the housing portion 12 of the housing 10 and the shielding plate 20 is fitted into the housing 10 so as to cover the housing portion 12.

(C) Next, the shielding board 50 is arrange | positioned on the mounting board | substrate 40 arrange | positioned on the support surface 11a of the board | substrate accommodating part 16 shown in FIG. Specifically, the protrusions 52 and 52 of the shielding plate 50 are fitted into the two positioning grooves 17 provided in the housing 10. As a result, the shielding plate 50 is disposed opposite to the shielding plate 20 with the bus bar 30 mounted on the housing 10 and the mounting substrate 40 interposed therebetween (see FIGS. 3 and 1).

(D) Further, the shielding plate presser 60 is assembled on the shielding plate 50 shown in FIG. The shield plate retainer 60 is assembled by fitting the hinge (male) 62a of the shield plate retainer 60 into the hinge (female) 18 of the housing 10 and rotating the retainer body 61 clockwise around the shaft portion 62 as a fulcrum. The lock hole 63 a of the presser 60 is locked by a lock claw 19 formed in the housing 10. At this time, the shielding plate 50 and the mounting substrate 40 are pressed by a boss 64 (see FIG. 1) provided on the back side of the shielding plate presser 60 (see FIGS. 4 and 1).

(E) Calibration is performed using the calibration terminal 46 in the state shown in FIG. In this state, since the substrate housing portion 16 remains open and the calibration terminal 46 is exposed, the harness of the inspection apparatus is connected to the calibration terminal 46 to calibrate the detection element 42. Can be performed.

(F) After performing calibration, the cover 70 is assembled. The cover 70 is assembled by engaging the lock claw 14a provided in the side wall 14 of the housing 10 with the lock hole 72a provided in the cover 70, and engaging the lock claw 14b and the lock hole 72b. (See FIG. 5).

  In this state, as shown in FIG. 7, the two shielding plates 20 and 50 are opposed to each other with the bus bar 30 and the mounting substrate 40 sandwiched in the space formed by the housing 10 and the cover 70. .

(effect)
(1) In the current detection device 1 according to the present embodiment, the shield plate 50 and the mounting substrate 40 are fixed to the housing 10 in a state in which the shield plate 50 and the mounting substrate 40 are pressed by the shield plate presser 60 before the cover 70 is assembled. At this time, the entire substrate housing portion 16 is not covered with the shielding plate 50 and the shielding plate holder 60, and the calibration terminal 46 is exposed (see FIG. 3). For this reason, calibration can be performed in an assembled state before the cover 70 is assembled.

(2) Conventionally, after performing calibration using the calibration terminal, when completely assembling, the jig holding method may change from the time of calibration, the assembly position accuracy of each part, etc. There was a risk that the detection performance at the time of calibration could not be demonstrated as the detection performance at the time of complete assembly. On the other hand, in the current detection device 1 according to the present embodiment, calibration can be performed in the assembled state, and the state of the mounting substrate 40, the shielding plate 50, and the shielding plate holder 60 is not changed. The terminal used for calibration can be covered by attaching the cover 70. For this reason, the detection performance at the time of calibration is exhibited as the detection performance at the time of complete assembly without causing any error in the assembly position accuracy of each part.

(3) Since it is not necessary to open a fitting hole with a projection provided on the fixed base in the shielding plate as in the prior art, a magnetic field does not leak from the fitting hole, and the detection output can be measured accurately. it can.

(4) Instead of fixing the shielding plate to the fixing base by heat melting as in the prior art, the shielding plate 50 can be easily fixed by simply fitting the shielding plate 50 into the housing 10 and fitting the shielding plate presser 60. it can.

(5) Since the shield plate presser 60 is provided with the shaft portion 62 and the hinge (male) 62a at one end of the presser body 61, the shield plate presser 60 is fitted into the hinge (female) 18 of the housing 10 and the presser body is used with the shaft portion 62 as a fulcrum. By rotating 61 in the clockwise direction, it can be easily assembled to the housing 10. Since the lock hole 63a is provided at the other end, the lock hole 63a can be easily fixed to the housing 10 by being locked by the lock claw 19 formed in the housing 10. Further, even when the boss 64 is formed high in order to increase the pressing force, it can be easily locked only by pressing only one locking end 63 portion.

(Other embodiments)
As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof. For example, in the above-described embodiment, the shield plate 50 having the shield plate main body 51 and the protrusions 52 erected in the vertical direction from both ends thereof is used. However, the flat shield formed only of the shield plate main body 51 is used. It can also be a plate. In this case, instead of providing the positioning groove 17 in the housing 10, a projection may be provided on the support surface 11a of the housing 10 to position the shielding plate.

DESCRIPTION OF SYMBOLS 1 Current detection apparatus 10 Housing 11 Main body part 11a Support surface 12 Housing | casing part 13 Connector part 13a Opening part 14 Side wall part 14a, 14b Lock claw 15 Positioning convex part 16 Substrate accommodating part (open end)
16a Concave portion 17 Positioning groove portion 18 Hinge (female)
DESCRIPTION OF SYMBOLS 19 Lock claw 20 Shielding board 21 Shielding board main body 22 Side wall part 30 Bus bar 31 Connection hole 40 Mounting board 41 Substrate main body 42 Detection element 43 Terminal connection part 44 Calibration connection part 45 Connection terminal 46 Calibration terminal 50 Shielding board 51 Shielding Plate body 52 Protruding part 60 Shield plate holder 61 Presser body 62 Shaft part 62a Hinge (male)
63 Locking end 63a Lock hole 64 Boss 70 Cover 71 Base part 72 Side wall part 72a Lock hole 73 Side wall part

Claims (5)

A housing to which the bus bar is mounted;
A mounting having a detection element for detecting a magnetic flux generated by a current flowing through the bus bar and a substrate on which the detection element is mounted, and mounted on the housing so that the detection element is disposed in the vicinity of the bus bar A substrate,
A shielding plate for magnetic shielding covering the mounting substrate;
A shielding plate presser that fixes the mounting substrate and the shielding plate in the housing while pressing;
A cover for accommodating the mounting board, the shielding plate and the shielding plate presser,
The mounting board has a calibration connection part,
The current detection device, wherein the shielding plate and the shielding plate presser are assembled to the housing with the calibration connection portion exposed.   The current detection device according to claim 1, wherein a pressing protrusion is provided on the shielding plate side of the shielding plate presser.   3. The current detection according to claim 1, wherein the shielding plate presser is assembled to the housing so as to be rotatable about one end as an axis, and a locking portion to the housing is provided at the other end. apparatus.   The shielding plate includes a main body formed in a rectangular shape and a protruding portion standing vertically from an end portion of the main body, and the protruding portion is formed so as to fit into a groove provided in the housing. The current detection device according to claim 1, wherein the current detection device is a current detection device.   5. The housing according to claim 1, wherein the housing has a support surface for supporting the mounting substrate, and the support surface is provided with a protrusion for positioning the mounting substrate in a planar direction. The current detection device according to claim 1.

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