JP2014078408A - Bus bar structure, and current sensor using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bus bar structure having an excellent inspection property, and a current sensor using the same.SOLUTION: A bus bar structure is composed of a bus bar 3 for current detection through which a current passes; and a mold member 2 covering the bus bar 3 while exposing one surface of one end portion of the bus bar 3. A tip end of the one end portion of the bus bar 3 has a bending/extending portion 3c bending/extending to a side surface 2d of the mold member 2. The bending/extending portion 3c is configured as a probe inspection portion on which a measuring probe 101 is pressed.

Description

  The present invention relates to a bus bar structure and a current sensor using the same.

  A current sensor for detecting a current flowing through the bus bar is attached to a power supply box mounted on the vehicle. As an example of this type of conventional power supply box, for example, a bus bar structure of a power supply box arranged in a peripheral part in an engine room has been proposed (see, for example, Patent Document 1).

  In the conventional bus bar structure described in Patent Document 1, the current sensor is held by being held by the holding frame of the power supply box, and the bus bar attached in a state of being penetrated through the current sensor is attached to the power supply box by the tightening screw. Tightened and fixed.

JP 2007-37375 A

  In this type of bus bar structure, the current probe is strongly pressed against the bus bar in a state where the bus bar is mounted on the power supply box, whereby a large current of several hundred amperes is applied to the bus bar, and the performance inspection of the current sensor is performed. Therefore, it is necessary to take measures to secure a space for pressing the current probe in the engine room.

  On the other hand, since the bus bar has a small bending rigidity in the thickness direction and easily deforms, when the pressing force of the current probe is applied to the bus bar, the pressing force is easily transmitted to the current sensor via the bus bar. Therefore, it is necessary to take measures to prevent the current sensor from being deformed or damaged by the pressing force of the current probe.

  The objective of this invention is providing the bus-bar structure excellent in testability, and the current sensor using the same.

[1] The present invention includes a current detection bus bar through which a current flows, and a mold member that covers the one end of the bus bar so that one end of the bus bar is exposed. A bus bar having a bent extension portion which is bent and extended with respect to a side surface of the member, and the bent extension portion is configured as a probe inspection portion for pressing the measurement probe. In the structure.

[2] In the invention described in [1] above, a hole is formed at one end of the bus bar, and a recess is formed in the mold member corresponding to the hole. The other bus bar is fixed to one end portion of the bus bar by a fixing member inserted through the recess.

[3] In the invention described in [2], the fixing member includes a bolt and a nut, the hole is a bolt insertion hole through which a screw portion of the bolt is inserted, and the recess is It is a nut accommodating part which accommodates a nut, It is characterized by the above-mentioned.

[4] The present invention further includes a magnetic detection element that detects the strength of a magnetic field generated when a current flows through the current detection bus bar according to any one of [1] to [3]. The current sensor is characterized.

  According to the present invention, the ease of inspection can be ensured.

It is a principal part perspective view which cuts in part and shows typically the electric current sensor provided with the typical bus-bar structure which concerns on embodiment of this invention. It is principal part sectional drawing of the II-II line arrow of FIG. 1 for demonstrating the test | inspection of the current sensor which concerns on embodiment.

  Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

(Overall configuration of current sensor)
In FIG. 1, reference numeral 1 indicating the whole is a current sensor having a typical bus bar structure in this embodiment. The current sensor 1 is a current sensor mounted on, for example, an inverter unit that controls a vehicle power supply, and is used to detect the magnitude of a current flowing through a vehicle motor or a battery.

  As shown in FIG. 1, the current sensor 1 includes a mold member 2 (hereinafter, referred to as “housing 2”). The housing 2 is covered with a current detection bus bar 3 having a long flat plate shape, which is a conductor through which current flows, by molding. A stepped portion 2 a having a stepped stepped surface is formed at one end of the housing 2. The stepped portion 2a protrudes from the molten resin with one surface of one end of the bus bar 3 exposed.

  As the molten resin, a material excellent in insulation and moisture resistance is preferable, and for example, polyphenylene sulfide (PPS) resin or the like is used. As the bus bar 3, for example, a metal material such as copper or a copper alloy is used.

  On the outer periphery of the bus bar 3, components such as a core (not shown) for collecting the magnetic field formed by the bus bar 3 and a magnetic detection element (not shown) for detecting the strength of the magnetic field generated by the current flowing through the bus bar 3 are provided. . As the magnetic detection element, for example, a GMR element, MR element, Hall element, Hall IC or the like is used.

(Bus bar structure)
As shown in FIGS. 1 and 2, a circular bolt insertion hole 3b is formed in the extending portion 3a protruding from the molten resin with one surface of one end of the bus bar 3 exposed. On the other hand, bolt insertion holes 4a are formed in the other bus bars 4 extending from the vehicle body side. The bus bar 3 and the bus bar 4 are fastened and fixed by bolts 5 and nuts 6 through the bolt insertion holes 3b and 4a.

  As shown in FIGS. 1 and 2, the housing 2 is formed with a nut accommodating portion 2 b that accommodates the nut 6 corresponding to the bolt insertion hole 3 b of the bus bar 3. A recess 2c for nut rotation prevention extending in the longitudinal direction is formed in the nut housing portion 2b. The screw portion of the bolt 5 is inserted into the nut accommodating portion 2b through the bolt insertion hole 4a of the bus bar 4 and the bolt insertion hole 3b of the bus bar 3, and is fixed by the nut 6 fitted in the recess 2c.

  In the current sensor 1 configured as described above, a performance test is performed to determine whether or not the current sensor 1 is formed as designed. In this performance inspection, the current probes 101 and 102 which are measurement probes for measuring the current flowing through the bus bar 3 and the current supply and current measurement to the bus bar 3 are performed, and the current measured by the current probes 101 and 102 is observed. This is performed using an inspection apparatus 100 including a measuring device 103.

  The inspection apparatus 100 is in contact with both ends of the bus bar 3 with the current probes 101 and 102 pressed against each other, and supplies a measurement current to the bus bar 3 through the current probes 101 and 102, thereby providing the current probes 101 and 102. The current measured by (1) is observed by the measuring instrument 103.

  The main basic configuration of the current sensor 1 according to this embodiment is the structure of the bus bar 3 having the installation position of the measurement probe. Therefore, the current sensor 1 configured as described above shows one configuration example according to this embodiment, and the shape and structure of the components are not limited to the illustrated example.

  As shown in FIGS. 1 and 2, a bent extending portion 3 c protruding from the side surface 2 d of the housing 2 is formed by bending at the tip of the extending portion 3 a of the bus bar 3. The bent extending portion 3c according to the illustrated example extends in a state of being joined to the side surface 2d of the housing 2, and is set as a probe inspection portion that presses the current probe 101 that measures the current flowing through the bus bar 3.

  The bent portion formed between the extended portion 3a and the bent extended portion 3c absorbs the force that presses the bent extended portion 3c by the current probe 101 when the current sensor 1 is inspected. The force in the pressing direction of the current probe 101 is relaxed. A bus bar structure having a simple structure and excellent inspectability can be effectively obtained.

(Effect of embodiment)
By adopting the bus bar structure configured as described above and the current sensor 1 using the bus bar structure, the following effects can be obtained in addition to the above effects.

(1) The inspection process of the current sensor 1 can be simplified, and the cost can be reduced.
(2) It becomes easy to set the current probe 101 at the inspection position of the bus bar 3, and the workability at the time of inspection can be improved.
(3) The force in the pressing direction of the current probe 101 is difficult to be transmitted to the current sensor 1 via the bus bar 3, and can be received in a direction advantageous in strength at the installation position of the magnetic detection element. As a result, the current sensor 1 can be prevented from being deformed or damaged.
(4) When a large current of several tens to several hundred amperes is allowed to flow through a bus bar used for a vehicle, and when this is measured with an ohmic contact, the pressing force of the current probe 101 in the current sensor performance test is extremely large. It becomes. In this embodiment, since the bending extension part 3c of the bus bar 3 is configured as a probe inspection part for pressing the current probe 101, deformation or breakage of the current sensor 1 can be prevented.

[Modification]
As mentioned above, although the bus-bar structure of this invention and the current sensor using the same were demonstrated based on the said embodiment and example of illustration, this invention is not limited to the said embodiment and example of illustration, The summary It is possible to implement in various embodiments without departing from the scope of the present invention. In the present invention, the following modifications are possible.

(1) The present invention can be applied to electric circuits other than electric circuits connected to vehicle motors and batteries.
(2) The present invention can be applied to a bus bar that connects an inverter device for a hybrid vehicle or an electric vehicle and a motor, or a bus bar for power supply that is connected to a battery.
(3) Since a motor for a hybrid vehicle or an electric vehicle is driven by a three-phase AC current, three bus bars for a three-phase AC power source are used for electrical connection to the outside. The present invention can be applied to a configuration in which magnetic detection elements are provided corresponding to each.
(4) The present invention can be applied to a current sensor that detects current using a core and a coreless current sensor that detects current without using a core.

  As is clear from the above description, typical embodiments, modifications, and illustrations according to the present invention have been illustrated. However, the above-described embodiments, modifications, and illustrations show the invention according to the claims. It is not limited. Therefore, it should be noted that not all the combinations of features described in the above-described embodiments, modifications, and illustrated examples are essential to the means for solving the problems of the invention.

DESCRIPTION OF SYMBOLS 1 ... Current sensor, 2 ... Mold member, 2a ... Step part, 2b ... Nut accommodating part, 2c ... Recess, 2d ... Side face, 3, 4 ... Bus bar, 3a ... Extension part, 3b, 4a ... Bolt insertion hole, 3c ... Bending extension part, 5 ... Bolt, 6 ... Nut, 100 ... Inspection device, 101,102 ... Current probe, 103 ... Measurement device

Claims (4)

A current detection busbar through which current flows;
A mold member that covers one surface of the bus bar in an exposed state; and
Composed of
The front end of one end of the bus bar has a bent extending portion that extends by bending with respect to the side surface of the mold member,
The bus bar structure, wherein the bent extension part is configured as a probe inspection part for pressing the measurement probe. A hole is formed at one end of the bus bar,
The mold member is formed with a recess corresponding to the hole,
2. The bus bar structure according to claim 1, wherein another bus bar is fixed to one end of the bus bar by a fixing member inserted into the recess through the hole. The fixing member includes a bolt and a nut,
The hole is a bolt insertion hole for inserting a screw portion of the bolt,
The bus bar structure according to claim 2, wherein the concave portion is a nut accommodating portion that accommodates the nut.   A current sensor comprising a magnetic detection element for detecting the strength of a magnetic field generated when a current flows through the current detection bus bar according to claim 1.

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