Current sensor

Abstract

This current sensor (1), which is used by being attached to a bus bar, is provided with: a magnetic sensor (5) capable of sensing a magnetic field generated from the bus bar (2) when a current to be measured flows; and a main body section (3) which has an insertion hole (4) into which the bus bar (2) can be inserted, and which houses the magnetic sensor (5), the main body section (3) being provided with: a stopper section (32) for locking the bus bar (2) inserted into the insertion hole (4) at a predetermined position in the Y-direction, which is the longitudinal direction of the bus bar (2); and a pressing rib (31) for forcibly fitting with a first protruding part (21) formed so as to protrude from a plate surface (2a) of the bus bar (2) in a state in which the second protruding part (22) of the bus bar (2) is locked to the stopper part (32), whereby positional displacement between the bus bar and the magnetic detection element can be suppressed.

Description

Technical Field

[0001] This invention relates to a current sensor for measuring the current flowing in various devices used in the control of vehicle power systems and the like. Background Technology

[0002] In recent years, current sensors have been used to measure the current flowing within various devices in order to control the power systems of vehicles equipped with various devices. Current sensors include integrated busbar types and separate busbar types used with the busbar. From the perspectives of standardization and cost reduction, separate busbar types are preferred. However, it is difficult to configure the busbar and the magnetic sensor (magnetic detection element) at a specified distance and maintain this positional relationship in separate busbar types. Therefore, there is a problem that measurement accuracy is easily degraded due to positional misalignment between the busbar and the magnetic sensor. Therefore, a separate busbar type current sensor with a mechanism to prevent positional misalignment between the busbar and the magnetic sensor has been proposed.

[0003] For example, Patent Document 1 describes a current sensor used in a busbar for stabilizing the distance between a magnetic sensor and a busbar in order to achieve high-precision current detection. The current sensor in this document includes, inside the annular outer shell portion of a non-magnetic housing: a first pressing unit for pressing a non-magnetic retainer holding the magnetic sensor against a partition wall; and a second pressing unit for pressing the busbar inserted into the insertion portion against the partition wall.

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2010-14477 Summary of the Invention

[0005] The technical problem that the invention aims to solve The current sensor in Patent Document 1 stabilizes the distance between the magnetic sensor and the busbar by pressing the holder of the magnetic sensor and the busbar against a pressing unit in the partition. However, since it is difficult to apply sufficient force through the pressing unit of the current sensor, there is a problem that the position of the magnetic sensing element and the busbar can easily shift when the busbar is inserted into the insertion part or when the busbar inserted into the insertion part is tightened into a specified position with screws. In addition, there is a problem that the pressing force of the pressing unit can easily shift when the pressing force of the busbar deteriorates due to heat, vibration, etc. of the busbar.

[0006] Therefore, the object of the present invention is to provide a current sensor for use in a busbar that suppresses the positional misalignment between the busbar and the magnetic detection element.

[0007] In addition, the objective is to provide a current sensor in which the positional offset between the magnetic sensing element and the busbar is small, even when the unit in which the current sensor is mounted deteriorates due to factors such as the heat generated by the current sensor.

[0008] Technical solutions for solving technical problems As a means of solving the above-mentioned problems, the present invention has the following configuration.

[0009] A current sensor includes: a magnetic sensor capable of sensing a magnetic field generated from a busbar when a measured current flows; and a main body for housing the magnetic sensor, characterized in that the main body includes: an insertion hole for inserting the busbar; a stop portion for locking the busbar inserted into the insertion hole at a predetermined position in the length direction of the busbar; and a compression rib for forcefully engaging with a first protrusion formed protruding from a plate surface of the busbar when the busbar is locked at the stop portion.

[0010] When the busbar is inserted into the through-hole, the first protrusion formed on the surface of the busbar is pressed in while crushing the compression rib provided on the main body. Therefore, when the busbar is inserted into the through-hole, the compression rib and the first protrusion are strongly engaged. Thus, with the busbar locked in place by the stop, the busbar can be securely fixed in a predetermined position on the main body. Therefore, positional misalignment between the busbar and the magnetic sensor can be reduced when the busbar is inserted into the through-hole or when the busbar is tightened with screws.

[0011] Alternatively, the stop portion can be formed to protrude from the first inner surface of the inner surface of the insertion hole, which faces the one plate surface of the busbar, and the stop portion contacts a second protrusion formed from the one plate surface of the busbar, thereby locking the busbar.

[0012] By having the first protrusion and the compression rib forcefully engaged in contact with a stop portion formed protruding from the first inner surface of the sensor body and a second protrusion formed protruding from one side of the busbar plate, and with the second protrusion abutting against the stop portion, the busbar can be fixed at a predetermined position in the insertion hole.

[0013] Alternatively, the stop portion is an opening surface surrounding the opening of the insertion hole, which locks the busbar by contacting a second protrusion formed protruding from the end face of the busbar in the width direction.

[0014] By using the opening surface surrounding the through hole as a stop, the busbar can be stopped at a specified position with a simple configuration.

[0015] Alternatively, the current sensor may be positioned such that, with the stop portion holding the busbar in a predetermined position, the magnetic sensor is located on the other side of the busbar.

[0016] Alternatively, the second inner surface of the inner surface of the insertion hole, which faces the other plate of the busbar, may have: a horizontal portion formed from one opening of the insertion hole toward the inside of the insertion hole, parallel to the first inner surface on which the compression rib is formed; and a conical portion formed such that the distance from the first inner surface approaches the inside of the insertion hole from the other opening of the insertion hole. The horizontal portion and the conical portion are adjacent to each other via a boundary ridge, which is formed in the extension direction of the busbar between the contact portion where the stop portion contacts the busbar and the strong engagement portion where the compression rib is strongly engaged with the busbar.

[0017] By providing a horizontal portion and a tapered portion on the second inner surface of the through hole, and positioning the boundary ridge between them between the contact portion and the strong engagement portion, the positional changes of the magnetic sensor and the busbar can be reduced as the compression rib deteriorates over time due to factors such as the heating of the busbar. In other words, the boundary ridge acts as a fulcrum during busbar movement, thus suppressing positional displacement of the busbar.

[0018] In addition, by setting the cone, the height of the opening on the other side is increased, thus improving the workability when inserting the busbar into the through hole.

[0019] Alternatively, when viewed along the direction in which the busbar and the magnetic sensor are stacked, the boundary edge overlaps with the magnetic sensor.

[0020] By placing a magnetic sensor near the boundary edge, the positional offset between the busbar and the magnetic sensor can be reduced.

[0021] Alternatively, when viewed along the direction in which the busbar and the magnetic sensor are stacked, the stop, the boundary edge, and the magnetic sensor overlap.

[0022] By arranging a stop portion in the stacking direction at a position overlapping with the boundary edge and the magnetic sensor, the movement of the busbar toward the stop portion can be suppressed, thereby reducing the positional offset between the busbar and the magnetic sensor.

[0023] A current sensor includes: a long, plate-shaped busbar for a measured current to flow through; a magnetic sensor capable of sensing a magnetic field generated from the busbar when the measured current flows; and a main body for housing the magnetic sensor. The busbar includes: a first protrusion formed protruding from one plate surface; and a locking portion for locking the busbar, inserted into a through-hole, at a predetermined position. The main body includes: the through-hole for insertion of the busbar; a compression rib formed inside the through-hole on a first inner surface facing one plate surface of the busbar, capable of strongly engaging with the first protrusion of the busbar; and a stop portion capable of locking the locking portion of the busbar. The busbar is mounted to the main body when the first protrusion is strongly engaged with the compression rib, the locking portion is in contact with the stop portion, and the magnetic sensor is located on the other plate surface side of the busbar, by inserting the busbar into the through-hole.

[0024] When the busbar inserted into the through hole is locked in the stop part, the first protrusion formed on the plate surface of the busbar is strongly engaged with the extrusion rib, thereby enabling the busbar to be installed in a predetermined position in the main body.

[0025] Alternatively, the busbar may have a fitting protrusion that protrudes in the width direction of the busbar in the portion within the insertion hole and disposed near the other opening when the busbar is inserted into the through hole and the engagement portion of the busbar is engaged with the stop portion. The through hole of the main body is formed such that its width increases as it moves from the one opening toward the other opening. The width of the one opening is approximately the same as the width of the busbar without the fitting protrusion, and the width of the other opening is approximately the same as the width of the busbar including the fitting protrusion.

[0026] With the busbar engaged by the stop portion of the main body, the busbar fits into the openings on both sides, thereby determining the position of the busbar in the width direction and reducing the positional offset between the busbar and the magnetic sensor.

[0027] Alternatively, the busbar may have a narrow section with a smaller width than the other sections between the first protrusion and the engaging section, and the magnetic sensor may be positioned opposite the narrow section.

[0028] By setting a narrow section in the busbar, the magnetic field generated around it when the measured current flows is strengthened, thus improving the measurement accuracy of the current sensor. Furthermore, when the current sensor detects alternating current, the degradation of frequency characteristics caused by the skin effect can be suppressed.

[0029] Invention Effects The current sensor of the present invention is installed on the main body by inserting a busbar into a through hole, wherein the first protrusion of the busbar is forcefully engaged with the compression rib of the main body, and the busbar is in contact with the stop portion of the main body. In this way, when the busbar is installed in a predetermined position on the main body, the busbar is forcefully engaged with the main body, thereby reducing the positional misalignment between the busbar and the magnetic sensor.

[0030] Furthermore, by providing a horizontal and a tapered portion on the second inner surface within the through-hole, and arranging these boundary ridges between the engaging portion and the compression rib in the extending direction of the busbar, the boundary ridges function as fulcrums for the busbar. Therefore, it is possible to reduce the positional misalignment between the busbar and the magnetic sensor in cases where the compression rib deteriorates due to heat, vibration, or other factors. Attached Figure Description

[0031] Figure 1A This is a perspective view of the current sensor and busbar according to the first embodiment.

[0032] Figure 1B This is a 3D view of a current sensor with a busbar installed.

[0033] Figure 2A yes Figure 1B A cross-sectional view of the current sensor at line AA.

[0034] Figure 2B yes Figure 2A A top view of the current sensor.

[0035] Figure 3A This is a cross-sectional view of a modified current sensor.

[0036] Figure 3B yes Figure 3A A top view of the current sensor.

[0037] Figure 4A This is a schematic diagram showing the positional relationship between the busbar and the main body during insertion.

[0038] Figure 4B yes Figure 4A A cross-sectional view of the current sensor at line AA.

[0039] Figure 5A This is a schematic diagram showing the positional relationship between the manifold and the main body when the first protrusion of the manifold contacts the extrusion rib.

[0040] Figure 5B yes Figure 5A A cross-sectional view of the current sensor at line AA.

[0041] Figure 6AThis is a schematic diagram showing the positional relationship between the busbar and the main body when the busbar is inserted into the specified position.

[0042] Figure 6B yes Figure 6A A cross-sectional view of the current sensor at line AA.

[0043] Figure 7A This is a schematic diagram showing the positional relationship between the busbar and the main body when the current sensor of the modified example is inserted.

[0044] Figure 7B yes Figure 7A A cross-sectional view of the current sensor at line AA.

[0045] Figure 7C yes Figure 7A Front view of the current sensor.

[0046] Figure 8 This is a schematic top view of a current sensor designed to prevent the busbar from shifting in the X direction.

[0047] Figure 9 This is a cross-sectional view of the current sensor according to the second embodiment.

[0048] Figure 10 This is a cross-sectional view of a modified current sensor.

[0049] Figure 11 It is a schematic cross-sectional view showing the situation where the busbar is fastened in the stepped section.

[0050] Figure 12 This is a simulated cross-sectional view illustrating the current sensor of the embodiment.

[0051] Figure 13 This is a simulated cross-sectional view illustrating the current sensor of the comparative example.

[0052] Figure 14A This is a graph showing the results of the embodiment (Z1 direction, no extrusion rib breakage).

[0053] Figure 14B This is a graph showing the results of the embodiment (Z1 direction, with crush rib damage).

[0054] Figure 15A This is a graph showing the results of the comparative example (Z1 direction, no extrusion rib breakage).

[0055] Figure 15B This is a chart showing the results of the comparative example (Z1 direction, with compression rib damage).

[0056] Figure 16AThis is a graph showing the results of the embodiment (Z2 direction, no extrusion rib breakage).

[0057] Figure 16B This is a graph showing the results of the embodiment (Z2 direction, with crush rib damage).

[0058] Figure 17A This is a graph showing the results of the comparative example (Z2 direction, no extrusion rib breakage).

[0059] Figure 17B This is a chart showing the results of the comparative example (Z2 direction, with compression rib damage). Detailed Implementation

[0060] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In each drawing, the same reference numerals are used to denote the same components, and descriptions are omitted. To indicate the positional relationship of the components, reference coordinates are appropriately shown in each drawing. In the reference coordinates, the width direction of the busbar is designated as the X direction, the extension direction of the busbar is designated as the Y direction, and the direction orthogonal to the X and Y directions is designated as the Z direction. The X direction is the direction of the sensitivity axis of the magnetic sensor, and the Y and Z directions are orthogonal to the sensitivity axis.

[0061] (First Implementation) Figure 1A This is a perspective view of the current sensor 1 and busbar 2 according to this embodiment. Figure 1B This is a perspective view of the current sensor 1 with the busbar 2 installed. As shown in these figures, the current sensor 1 is a split-type current sensor with the busbar 2 inserted and installed in the through hole 4 of the main body 3, and the busbar 2 is not embedded in the main body 3.

[0062] Figure 2A It is a schematic representation Figure 1B A cross-sectional view of the current sensor 1 at line AA. Figure 2B This is a top view schematically showing the configuration of current sensor 1.

[0063] The busbar 2 is a long plate, with its surface 2b facing the magnetic sensor 5. It has a first protrusion 21 and a second protrusion (engaging portion) 22 at different positions along its extension direction, i.e., the Y direction. Both the first protrusion 21 and the second protrusion 22 protrude from the surface 2a. The first protrusion 21 and the second protrusion 22 are used to install and hold the busbar 2, which is inserted into the insertion hole 4 of the main body 3, in a predetermined position.

[0064] With the busbar 2 installed in the designated position of the insertion hole 4, the first protrusion 21 and the second protrusion 22 are disposed inside the insertion hole 4, and the two ends of the busbar 2 protrude from the opening 41 on the Y1 side and the opening 42 on the Y2 side of the insertion hole 4, respectively.

[0065] The main body 3 has an insertion hole 4 for inserting the busbar 2, a compression rib 31, and a stop 32.

[0066] The extrusion rib 31 is a surface inside the insertion hole 4, formed on the first inner surface 4a opposite to a plate surface 2a of the busbar 2. When the busbar 2 is locked in the stop part 32, it is strongly engaged with the first protrusion 21 of the busbar 2.

[0067] The stop portion 32 is formed to protrude from the first inner surface 4a within the insertion hole 4. When the busbar 2 is inserted into the insertion hole 4, a second protrusion 22, which protrudes from one plate surface 2a, abuts against the stop portion 32, thereby locking the busbar 2 at a predetermined position in the extension direction of the busbar 2, i.e., the Y direction. With the busbar 2 locked in place by the stop portion 32, the magnetic sensor 5 is located on the other plate surface 2b side of the busbar 2.

[0068] When the busbar 2 is inserted into the insertion hole 4 of the main body 3, the first protrusion 21 of the busbar 2 moves while crushing a portion of the compression rib 31 of the main body 3, thereby forcefully engaging the first protrusion 21 with the compression rib 31. Furthermore, at a predetermined position in the Y direction, with the second protrusion 22 of the busbar 2 in contact with the stop portion 32 of the main body 3, the insertion of the busbar 2 into the insertion hole 4 is completed, and the busbar 2 is installed on the main body 3.

[0069] The compression rib 31 is located near the opening 42 on the Y2 side. Therefore, even if part of the compression rib 31 is crushed and dirt is generated, the likelihood of dirt moving to the busbar 2 near the opening 41 on the Y1 side is low. Furthermore, the first protrusion 21, which strongly engages with the compression rib 31, stops closer to the opening 42 on the Y2 side within the insertion hole 4, making it difficult for the compression rib 31 to be scraped off. Therefore, the possibility of dirt affecting welding and other processes used to secure the busbar 2 near the opening 41 on the Y1 side and the opening 42 on the Y2 side to other components is reduced.

[0070] Figure 2A as well as Figure 2B The busbar 2 has two protrusions, but it can also be configured to have three or more protrusions. Alternatively, it can be configured such that a recess is formed on the plate surface 2a instead of the second protrusion 22, which engages with the protrusion on the first inner surface 4a of the insertion hole 4 formed in the main body 3, thereby locking the busbar 2 at a predetermined position in the Y direction. With this configuration, the amount of metal used in the busbar 2 can be reduced.

[0071] Inside the main body 3, there is a magnetic sensor 5 and a magnetic shield 6 arranged opposite to the busbar 2.

[0072] The magnetic sensor 5 has a magnetoresistive element that senses the magnetic field generated from the busbar 2 when the current to be measured flows. Examples of magnetoresistive elements include giant magnetoresistive (GMR) elements, anisotropic magnetoresistive (AMR) elements, tunneling magnetoresistive (TMR) elements, and Hall elements. The magnetic sensor 5 is mounted on a substrate 7, which is attached to the main body 3.

[0073] The busbar 2 is held in a state where the first protrusion 21 is forcefully engaged with the compression rib 31 and the second protrusion 22 is in contact with the stop 32. In this state, the magnetic sensor 5 is positioned partially opposite to the first protrusion 21 and the second protrusion 22 of the busbar 2.

[0074] The magnetic shielding member 6 is, for example, constructed by overlapping multiple metal plates of the same shape. By providing the magnetic shielding member 6, the magnetic noise from the outside to the magnetic sensor 5 is reduced, thus improving the measurement accuracy of the magnetic sensor 5. In the current sensor 1, plate-shaped magnetic shielding members 6 are provided on both sides of the magnetic sensor 5 in the Z direction. The magnetic shielding member 6 on the Z1 side is embedded in the main body 3, and the magnetic shielding member 6 on the Z2 side is provided on the side of the substrate 7 opposite to the side where the magnetic sensor 5 is disposed. U-shaped or C-shaped (core-shaped) magnetic shielding members can also be used instead of plate-shaped magnetic shielding members 6.

[0075] By making the width of the insertion hole 4 match the width of the busbar 2, the position of the busbar 2 in the X direction within the main body 3 can be determined. By making the second protrusion 22 of the busbar 2 contact the stop portion 32 of the main body 3, the busbar 2 can be stopped when it is inserted into a predetermined position, thereby determining the position of the busbar 2 in the Y direction within the main body 3. Furthermore, when the busbar 2 is inserted into the predetermined position, by forcefully engaging the first protrusion 21 of the busbar 2 with the compression rib 31 of the main body 3, the position of the busbar 2 in the Z direction within the main body 3 can be determined.

[0076] Furthermore, although it is shown that the width of the through-hole 4 is the same as the width of the busbar 2, the dimensions are actually managed in such a way that the width of the through-hole 4 is larger to prevent significant wobble between the through-hole 4 and the busbar 2. When the width of the through-hole 4 and the width of the busbar 2 are exactly the same, the frictional resistance when inserting the busbar 2 into the through-hole 4 becomes very high. This is because if the frictional resistance during insertion is high, the busbar 2 may deform when inserted into the through-hole 4, or the busbar 2 may cut into the inner surface of the through-hole 4, generating cutting powder, etc.

[0077] As described above, the busbar 2 can be inserted into the through hole 4 of the main body 3, and the busbar 2 can be installed in the designated position of the main body 3. With the busbar 2 installed in the main body 3, the first protrusion 21 of the busbar 2 is strongly engaged with the compression rib 31 of the main body 3. Therefore, it is possible to prevent the position of the busbar 2 in the main body 3 from shifting during installation or shifting when it is fastened to other components after installation.

[0078] (Modified example) Figure 3A This is a schematic cross-sectional view illustrating the configuration of a modified current sensor 1. Figure 3B yes Figure 3A Top view of current sensor 1.

[0079] In the modified current sensor 1, a second protrusion 23 protruding from the side surface 2c and side surface 2d in the width direction (X direction) of the busbar 2 replaces the second protrusion 22 protruding from the plate surface 2a. When the busbar 2 is inserted into the through hole 4, the second protrusion 23 abuts against the opening surface 33 of the main body 3, thereby locking the busbar 2 in a predetermined position within the main body 3. With the busbar 2 locked in the predetermined position by the second protrusion 23 and the opening surface 33, the first protrusion 21 of the busbar 2 is forcefully engaged with the compression rib 31 of the main body 3. The opening surface 33 is the surface on the outer surface of the main body 3 that surrounds the periphery of the opening 41 of the through hole 4.

[0080] In this way, in the modified example, the current sensor 1 stops the busbar 2 by contacting the opening surface 33 of the main body 3 with the second protrusion 23 of the busbar 2, thus eliminating the need to provide a stop part 32 in the main body 3. Therefore, the main body 3 can be made to have a simpler configuration.

[0081] Figure 4A This is a schematic diagram illustrating the positional relationship between the busbar 2 and the main body 3 during insertion. In this diagram, solid lines are used to represent the parts other than the magnetic sensor 5 in order to show the positional relationship of each part when viewed along the Z direction. Figure 4B It is a schematic representation Figure 4A A cross-sectional view of the current sensor 1 at line AA. Furthermore, Figure 5A , Figure 6A as well as Figure 7A Similarly, solid lines are used to represent different parts in order to make it easier to show the positional relationships.

[0082] like Figure 4A As shown, the first protrusion 21 and the second protrusion 22 in the busbar 2 are rectangular protrusions when viewed from above. Furthermore, the compression rib 31 and the stop portion 32 in the main body 3 are composed of two rectangular protrusions with the Y direction as their length direction.

[0083] In addition, the dimension in the X direction of the extrusion rib 31 is set such that it has a strength that allows it to be intentionally deformed (crushed) when it comes into contact with the first protrusion 21 and is then pressed into the Y2 direction. In addition, the dimension in the X direction of the stopper 32 is set such that it has a strength that prevents it from being deformed (crushed) when it comes into contact with the second protrusion 22 and is then pressed into the Y2 direction. The extrusion rib 31 is provided between the two protrusions of the stopper 32, and the width d1 of the first protrusion 21 of the bus bar 2 in the X direction, the width d2 of the second protrusion 22, the width D1 inside the two protrusions of the extrusion rib 31, and the width D2 inside the two protrusions of the stopper 32 satisfy the relationship D1 < d1 < D2 < d2.

[0084] In addition, as Figure 4B shown, the height h1 of the first protrusion 21 of the current sensor 1 in the Z direction from the plate surface 2b, the height h2 of the second protrusion 22 from the plate surface 2b, the height H0 of the through hole 4, the height H1 of the gap between the second inner surface 4b of the through hole 4 facing the other plate surface 2a of the bus bar 2 and the extrusion rib 31, and the height H2 of the gap between the second inner surface 4b and the stopper 32 satisfy the relationship H1 < H2 < h1 < h2 < H0.

[0085] The width d1 of the first protrusion 21 of the bus bar 2 is smaller than the width D2 between the two rectangular protrusions of the stopper 32. Therefore, until the first protrusion 21 with the height h1 of the bus bar 2 comes into contact with the extrusion rib 31 in the through hole 4, it passes through the through hole 4 with the height H0 between the two rectangular protrusions of the stopper 32 without interfering with the stopper 32.

[0086] Figure 5A is a schematic diagram showing the positional relationship between the bus bar 2 and the main body portion 3 when the first protrusion 21 of the bus bar 2 comes into contact with the extrusion rib 31. Figure 5B is schematically showing Figure 5A a cross-sectional view of the structure of the current sensor 1 at the AA line of

[0087] Figure 6A is a schematic diagram showing the positional relationship between the bus bar 2 and the main body portion 3 when the bus bar 2 is inserted into the specified position. Figure 6B is schematically showing Figure 6A a cross-sectional view of the structure of the current sensor 1 at the AA line of [[ID=?]]There is an issue with the provided text as the tag [[ID=?]] is not well-defined. It seems to be an incomplete or incorrect tag. Please review and correct the text for a proper translation.

[0088] The height h1 of the first protrusion 21 is greater than the height H1 of the gap in the portion of the through hole 4 where the extrusion rib 31 is provided. Therefore, from the Figure 5A position shown in Figure 6ABetween the positions shown, the first protrusion 21 moves while crushing a portion of the compression rib 31, thereby maintaining the first protrusion 21 in contact with the compression rib 31 in the Z direction. According to this configuration, the busbar 2 is pressed into the insertion hole 4, and the first protrusion 21 of the busbar 2 is strongly engaged with the compression rib 31 of the main body 3.

[0089] Therefore, with the second protrusion 22 abutting against the stop 32, the Z-direction position of the busbar 2 in the main body 3 can be fixed by the strong engagement of the first protrusion 21 and the compression rib 31. Furthermore, the Y-direction position of the busbar 2 in the main body 3 is determined by the engagement of the second protrusion 22 and the stop 32. Additionally, the X-direction position of the busbar 2 in the main body 3 is determined by aligning the width of the busbar 2 with that of the through hole 4.

[0090] like Figure 6A and Figure 6B As shown, the busbar 2 has a narrow section 25 between the first protrusion 21 and the second protrusion 22, with a width dimension in the X direction smaller than the other parts. With the busbar 2 installed in a predetermined position on the main body 3, the magnetic sensor 5 is positioned opposite the narrow section 25. Near the narrow section 25, a stronger magnetic field is generated than in other parts when the measured current flows through the busbar 2. Therefore, the magnetic sensor 5 can efficiently sense the magnetic field generated when the measured current flows through the busbar 2. Furthermore, when the magnetic sensor 5 detects alternating current flowing through the busbar 2, it can suppress the degradation of frequency characteristics caused by the skin effect.

[0091] (Modified example) Figure 7A This is a schematic diagram showing the positional relationship between the busbar 2 and the main body 3 during insertion. Figure 7B It is a schematic representation Figure 7A A cross-sectional view of the current sensor 1 of the AA line. Figure 7C Viewed from the Y2 side towards the Y1 direction Figure 7A The front view of the current sensor 1.

[0092] like Figure 7A As shown, the structure of the first protrusion 21 and the second protrusion 22 in the busbar 2 is similar to... Figure 4A The manner shown is the same. The stop portion 32 in the main body 3 is formed by a rectangular protrusion, and the pressing rib 31 is provided protruding from the stop portion 32 rather than from the first inner surface 4a inside the insertion hole 4, which is consistent with the other aspects. Figure 4A The methods shown are different.

[0093] like Figure 7BAs shown, in the modified current sensor 1, the height h1 of the first protrusion 21 in the Z direction, the height h2 of the second protrusion 22, the height H0 of the through hole 4, the height H1 of the gap between the second inner surface 4b of the through hole 4 opposite to the other plate surface 2a of the busbar 2 and the compression rib 31, and the height H2 of the gap between the second inner surface 4b and the stop part 32 satisfy H1.

[0094] In the modified example, the height h1 of the first protrusion 21 is smaller than the height H2 of the gap. Therefore, the first protrusion 21 of height h1 of the busbar 2 passes through the gap of height H2 without interfering with the stop part 32 until it contacts the compression rib 31 in the insertion hole 4.

[0095] like Figure 7C As shown, when viewed from the Y2 to Y1 direction, a portion of the first protrusion 21 of the busbar 2 overlaps with a portion of the compression rib 31 of the main body 3. Therefore, when the second protrusion 22 of the busbar 2 is in contact with the stop portion 32 of the main body 3, the first protrusion 21 of the busbar 2 is strongly engaged with the compression rib 31 of the main body 3.

[0096] Figure 8 This is a top view schematically showing the configuration that the current sensor 1 of this embodiment can have to prevent the busbar 2 from shifting in the X direction.

[0097] As shown in the figure, the through hole 4 can also be configured such that, when viewed along the stacking direction of the busbar 2 and the magnetic sensor 5, i.e. the Z direction, the width dimension D41 of the opening 41 is larger than the width dimension D42 of the opening 42, and is set such that the width dimension increases as it moves from the opening 42 toward the opening 41.

[0098] Alternatively, the busbar 2 may also have a second protrusion 22 on each side in the width direction (X direction) of the busbar 2, which is engaged with the stop portion 32 (see reference). Figure 6A , Figure 6B The fitting protrusion 24 is located within the insertion hole 4 and near the opening 41, protruding in the width direction (X direction) of the busbar 2.

[0099] The width dimension D42 of the opening 42 is approximately the same as the width dimension D0 of the busbar 2 at the part without the fitting protrusion 24, and the width dimension D41 of the opening 41 is approximately the same as the width dimension D24 of the busbar 2 including the fitting protrusion 24.

[0100] Based on the above Figure 8 With the configuration shown, when the second protrusion 22 of the busbar 2 is engaged with the stop 32, the openings 41 and 42 on both sides of the through hole 4 are fitted with the busbar 2, enabling the positioning of the main body 3 in the X direction.​

[0101] (Second Implementation) Figure 9 This is a cross-sectional view of the current sensor 8 in this embodiment.

[0102] The current sensor 8 differs from the current sensor 1 in the first embodiment in that it has a horizontal portion 43 and a conical portion 44 on the second inner surface 4b of the insertion hole 4 opposite to the plate surface 2b of the busbar 2.

[0103] The horizontal portion 43 is a planar portion formed from the opening 42 in the insertion hole 4 toward the inside of the insertion hole 4 (in the direction from Y2 to Y1) and parallel to the first inner surface 4a. The horizontal portion 43 is formed to be parallel to the plate surface 2b of the busbar 2 when the busbar 2 is installed in a predetermined position in the main body portion 3.

[0104] The cone portion 44 is formed such that it approaches the inside of the insertion hole 4 (from Y1 to Y2) from the opening 41 in the insertion hole 4 at a distance from the first inner surface 4a, and is inclined relative to the plate surface 2b of the busbar 2 when the busbar 2 is installed. The cone portion 44 is formed such that the distance between it and the plate surface 2b of the busbar 2 in the insertion hole 4 decreases as it moves into the insertion hole 4. That is, the cone portion 44 is formed such that, when the busbar 2 is installed in a predetermined position in the main body portion 3, the distance between it and the plate surface 2b of the busbar 2 approaches the inside of the insertion hole 4.

[0105] The horizontal portion 43 and the conical portion 44 are adjacent to each other across the boundary edge 45. That is, the horizontal portion 43 and the conical portion 44 are continuously arranged with the boundary edge 45 as the boundary.

[0106] With the busbar 2 installed in the designated position in the main body 3, the boundary ridge line 45 is located between the first protrusion 21 and the second protrusion 22 of the busbar 2 in the Y direction, which is the extension direction of the busbar 2. That is, the boundary ridge line 45 is formed between the contact portion 320 of the stop portion 32 with the second protrusion 22 of the busbar 2 and the strong engagement portion 310 of the compression rib 31 with the first protrusion 21 of the busbar 2.

[0107] If the compression rib 31 softens over time due to high temperature, vibration, etc., reducing its ability to position the busbar 2 in the Z direction, the end of the busbar 2 on the Y1 side may tilt towards the Z1 side due to the mounting posture of the current sensor 8. The boundary ridge 45 functions as a fulcrum when the busbar 2 tilts as described above. That is, when the busbar 2 tilts, the plate surface 2b of the busbar 2 moves away from the horizontal portion 43, but the separation distance is 0 at the boundary ridge 45, and the closer to the boundary ridge 45, the smaller the separation distance. The portion of the busbar 2 that faces the magnetic sensor 5 is located near the boundary ridge 45, thus reducing the change in the distance between the magnetic sensor 5 and the busbar 2 when the busbar 2 tilts.

[0108] Furthermore, by arranging the magnetic sensor 5 at a position overlapping with the stop 32 when viewed along the Z direction, the stop 32 can be used to restrict the movement of the Y1 side end of the busbar 2 in the Z2 direction. Therefore, the displacement of the distance between the magnetic sensor 5 and the busbar 2 can be suppressed, reducing the change in the distance between the magnetic sensor 5 and the busbar 2 when the busbar 2 is tilted.

[0109] Therefore, it is possible to suppress the decrease in the measurement accuracy of the current sensor 8 caused by the change in the distance between the magnetic sensor 5 and the busbar 2.

[0110] (Modified example) Figure 10 This is a cross-sectional view of a modified example of the current sensor 8.

[0111] In the modified example shown in the figure, when viewed along the Z direction where the busbar 2 and the magnetic sensor 5 are stacked, the magnetic sensor 5 is positioned at a location overlapping the boundary edge 45 and the stop portion 32. Figure 9 The current sensor 8 is different. According to this configuration, the magnetic sensor 5 is located near the boundary ridge 45, which functions as a fulcrum when the end of the busbar 2 on the Y1 side is tilted towards the Z1 side. Therefore, the displacement of the distance between the magnetic sensor 5 and the busbar 2 can be further reduced.

[0112] Figure 11 This is a schematic cross-sectional view showing the case where the busbar 2 of the modified current sensor 8 is fastened to the part with the step.

[0113] As shown in the figure, when the Y1 side end of the busbar 2 is installed to the fastening part 82 via the fastening unit 81, sometimes a force in the Z1 direction is applied to the Y1 side end of the busbar 2, causing the busbar 2 to tilt as shown by the dashed line. In such cases, by providing the cone 44, the busbar 2 tilts with the boundary ridge 45 as the fulcrum. That is, near the boundary ridge 45, even if the busbar 2 tilts, the relative position of the busbar 2 and the boundary ridge 45 hardly changes, thus reducing the amount of displacement of the busbar 2 near the boundary ridge 45. Therefore, in the envisioned Figure 11 When the current sensor 8 is installed as shown, by placing the magnetic sensor 5 near the boundary edge 45, the effect of the positional misalignment between the busbar 2 and the magnetic sensor 5 can be reduced more effectively.

[0114] The smaller the positional offset between busbar 2 and magnetic sensor 5, the smaller the measurement error of current sensor 8 can be. Furthermore, Figure 11 The dashed line in the diagram shows the Y1 side of the busbar 2, which is mounted to the fastening part 82 via the fastening unit 81, and the first protrusion 21 is loosely and forcefully engaged with the compression rib 31. With the first protrusion 21 and the compression rib 31 in a forcefully engaged state, the Y2 side of the busbar 2 remains in contact with... Figure 11 The solid line in the middle indicates the same state as busbar 2.

[0115] [Example] Figure 12 This is a cross-sectional view of the current sensor 8 illustrating the simulation method of this embodiment. As shown in the figure, regarding a variation of the current sensor 8 in the second embodiment, the displacement generated on the substrate 7 where the busbar 2 and the magnetic sensor 5 are disposed is simulated when the Y1 side end of the busbar 2 is displaced in the Z1 or Z2 direction. The evaluation based on the simulated displacement is performed for the case where the extrusion rib 31 is not damaged and the case where the extrusion rib 31 is damaged.

[0116] Figure 13 This is a cross-sectional view of a comparative example current sensor 80. As shown in the figure, for the current sensor 80, which has compression ribs 31 provided on both sides in the Y direction across the magnetic sensor 5, in conjunction with... Figure 12 The current sensor 8 was simulated under the same conditions.

[0117] Figure 14A as well as Figure 14B Simulation results are shown for embodiments in which the busbar 2 is displaced in the Z1 direction, with and without damage to the compression rib 31.

[0118] Figure 15A as well as Figure 15BThe simulation results show comparative examples of displacement of the busbar 2 in the Z1 direction with and without damage to the compression rib 31.

[0119] In the various charts, Y-axis position 0 represents the location of the magnetic sensor 5 on the substrate 7, and the difference in output values ​​marked with arrows represents the relative positional offset between the busbar 2 and the magnetic sensor 5. Figures 16A-17B (The same applies).

[0120] When the Y1 side end of the busbar 2 is moved in the Z1 direction, regardless of whether the compression rib 31 is damaged, the positional offset between the busbar 2 and the magnetic sensor 5 disposed on the substrate 7 is significantly reduced compared to the current sensor 80 of the comparative example. This result is believed to be because, by providing the tapered portion 44, the fulcrum for the busbar 2 during displacement is... Figure 13 The opening 41, indicated by a black circle in the middle, faces... Figure 12 The boundary edge 45, indicated by the black circle, moves, and the position offset of the confluence strip 2 near the boundary edge 45 becomes smaller.

[0121] Figure 16A as well as Figure 16B The results of embodiments showing displacement of the busbar 2 in the Z2 direction are shown, both with and without damage to the compression rib 31.

[0122] Figure 17A as well as Figure 17B The results of a comparative example are shown, in the case where the compression rib 31 is undamaged and in the case where the compression rib 31 is damaged, the busbar 2 is displaced in the Z2 direction.

[0123] When the Y1 side end of the busbar 2 is moved in the Z2 direction, if the compression rib 31 is not damaged, the positional offset in the current sensor 8 of the embodiment is the same as that in the current sensor 80 of the comparative example. If the compression rib 31 is damaged, the positional offset in the current sensor 8 of the embodiment is slightly lower than that in the current sensor 80 of the comparative example. Figure 12 and Figure 13 As shown by the black circle, the fulcrum for the busbar 2 during displacement is the opening 42 in both the current sensor 8 of the embodiment and the current sensor 80 of the comparative example. Therefore, it is believed that the result of the compression rib 31 being damaged is due to the fact that the displacement of the busbar 2 is suppressed by the stop portion 32 in the current sensor 8 of the embodiment.

[0124] In summary, the simulation results are as follows: In the current sensor 8 of the embodiment, when the Y1 side end of the busbar 2 is moved in the Z1 direction, the busbar 2 tilts with the boundary ridge 45 as the fulcrum. Therefore, the closer the magnetic sensor 5 is to the position opposite the boundary ridge 45, the smaller the positional offset between the magnetic sensor 5 and the busbar 2 can be suppressed. When the Y1 side end of the busbar 2 is moved in the Z2 direction, the busbar 2 tilts with the Z1 side end of the opening 42 as the fulcrum. Therefore, the closer the magnetic sensor 5 is to the position opposite the Z1 side end of the opening 42, the smaller the positional offset between the magnetic sensor 5 and the busbar 2 can be suppressed. Therefore, when the magnetic sensor 5 is positioned opposite the region between the boundary ridge 45 and the opening 42, even if the Y1 type end of the busbar 2 is moved in either the Z1 or Z2 direction, it is difficult for the positional offset between the busbar 2 and the magnetic sensor 5 to become extremely large. Therefore, when the magnetic sensor 5 is positioned opposite the region between the boundary ridge 45 and the opening 42, the measurement error of the current sensor 8 can be suppressed even if the position of the busbar 2 changes in the Z direction.

[0125] The embodiments disclosed in this specification are illustrative in all respects and are not intended to limit the scope of the invention. The scope of the invention is not limited to the description of the foregoing embodiments, but is defined by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0126] [Industrial Applicability] The present invention is useful as a current sensor for measuring the current flowing in various devices used in the control of, for example, the power system of a vehicle.

[0127] Explanation of reference numerals in the attached figures 1: Current sensor 2: Busbar 2a: Board surface 2b: Board surface 2c: Side view 2D: Side View 21: First protrusion 22: Second protrusion 23: Second protrusion 24: Fitting convex part 25: Narrow section 3: Main body 31: Compression Rib 310: High-strength fitting part 32: Stop section 320: Contact Department 33: Open face 4: Through hole 4a: First inner surface 4b: Second inner surface 41: Opening 42: Opening 43: Horizontal section 44: Conical part 45: Boundary Edge 5: Magnetic sensor 6: Magnetic shielding components 7: Substrate 8: Current sensor 80: Current sensor 81: Fastening Unit 82: Fastening parts H0: Height H1: Height H2: Height h1: Height h2: Height D1: Width D2: Width d1: Width d2: Width D0: Width dimension D24: Width dimension D41: Width dimension D42: Width dimension.

Claims

1. A current sensor, comprising: A magnetic sensor is capable of sensing the magnetic field generated from a busbar when a measured current flows; and The main body houses the magnetic sensor, characterized in that... The main body comprises: The through-hole allows the busbar to be inserted; A stop portion is used to lock the busbar inserted into the through hole at a predetermined position in the length direction of the busbar; as well as The compression rib is used to forcefully engage with a first protrusion formed protruding from one surface of the busbar when the busbar is locked in place by the stop.

2. The current sensor according to claim 1, characterized in that, The stop portion is formed to protrude from the first inner surface of the inner surface of the through hole, which is opposite to one of the plate faces of the busbar. The stop portion contacts a second protrusion formed from one of the plates of the busbar, thereby locking the busbar.

3. The current sensor according to claim 1, characterized in that, The stop portion is an opening surface surrounding the opening of the insertion hole, which locks the busbar in place by contacting a second protrusion formed protruding from the end face of the busbar in the width direction.

4. The current sensor according to claim 1, characterized in that, With the stop portion holding the busbar in a predetermined position, the magnetic sensor is located on the other side of the busbar.

5. The current sensor according to claim 4, characterized in that, The second inner surface, which is the surface of the through hole facing the other plate of the busbar, has the following characteristics: The horizontal portion, extending from one opening in the insertion hole towards the inside of the insertion hole, is formed as a plane parallel to the first inner surface on which the compression rib is formed; and The tapered portion is formed such that the distance to the first inner surface decreases as it moves from another opening in the through-hole toward the inside of the through-hole. The horizontal portion and the conical portion are adjacent to each other via a boundary ridge. The boundary ridge is formed in the extension direction of the busbar between the contact portion where the stop portion contacts the busbar and the strong fitting portion where the extrusion rib strongly fits into the busbar.

6. The current sensor according to claim 5, characterized in that, When viewed along the direction in which the busbar and the magnetic sensor are stacked, the boundary ridge overlaps with the magnetic sensor.

7. The current sensor according to claim 5, characterized in that, When viewed along the direction in which the busbar and the magnetic sensor are stacked, the stop, the boundary ridge, and the magnetic sensor overlap.

8. A current sensor, comprising: A long, plate-shaped busbar for the flow of the current being measured; A magnetic sensor capable of sensing the magnetic field generated from the busbar when the measured current flows; and The main body houses the magnetic sensor, characterized in that... The bus bar has the following features: The first protrusion is formed protruding from a plate surface; and The engaging part is used to lock the busbar inserted into the through hole in a predetermined position. The main body comprises: The through hole allows the busbar to be inserted; The extrusion rib, formed inside the through hole on the first inner surface facing one of the plates of the busbar, can be strongly engaged with the first protrusion of the busbar. as well as The stop portion is capable of locking the engaging portion of the busbar. By inserting the manifold into the through-hole. Thus, the busbar is installed on the main body when the first protrusion is strongly engaged with the extrusion rib, the engaging part is in contact with the stop part, and the magnetic sensor is located on the other side of the busbar.

9. The current sensor according to claim 8, characterized in that, The busbar has a fitting protrusion that protrudes in the width direction of the busbar within the through hole and near the other opening, when the busbar is inserted into the through hole and the engaging portion of the busbar is engaged with the stop portion. The through hole in the main body is formed such that its width increases as it moves from one opening toward the other opening. The width of one opening is approximately the same as the width of the busbar without the fitting protrusion, and the width of the other opening is approximately the same as the width of the busbar including the fitting protrusion.

10. The current sensor according to claim 8, characterized in that, The busbar has a narrow section between the first protrusion and the engaging portion, which is smaller in width than the other portions. The magnetic sensor is positioned opposite the narrow section.

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