JP6147111B2 - Mounting mechanism and measuring device - Google Patents

Description

  The present invention relates to an attachment mechanism for attaching an annular current detection unit to an attachment target, and a measurement apparatus including the attachment mechanism.

  As this type of attachment mechanism, an attachment structure disclosed by the applicant in Japanese Patent No. 3581769 is known. This mounting structure is a structure for mounting a current transformer having a through hole to a chassis portion of a current measuring device, and includes an insulating case, a sleeve, one interposition coupling fitting, and two sets of bolt-shaped conductors and It is configured with a nut.

  In addition, as shown in FIGS. 10 and 11, the applicant has developed a mounting structure 303 for attaching the current transformer 301 using two interposed connecting fittings 314, a set of bolt-shaped conductors 315 and nuts 316. ing. In this attachment structure 303, first, the other end portions 314 b of the two interposition connection fittings 314 are fixed to the terminal block 420 attached to the chassis 410. Next, in a state where the insulating cases 311a and 311b (insulating cases 311a and 311b housing the current transformer 301) are sandwiched between the one end portions 314a of the two interposed connecting metal fittings 314, one of the intermediate connecting metal fittings 314 (in both drawings) An insertion hole 322 in one end 314a of the lower intervention coupling fitting 314), a cylindrical sleeve 313 inserted in the insulating cases 311a and 311b, and the other intervention coupling fitting 314 (upper intervention coupling in both figures). The bolt-shaped conductor 315 is inserted through the insertion hole 322 of the one end 314a of the metal fitting 314). Subsequently, the insulating cases 311a and 311b are fixed by attaching and tightening the nuts 316 to the protruding portions 315b protruding from the insertion holes 322 of the other interposed coupling fitting 314.

Japanese Patent No. 3581769 (page 2-3, Fig. 1-3)

  However, the above-described mounting structure 303 using the two interposing connection fittings 314 and a set of bolt-shaped conductors 315 has the following problems to be improved. That is, in this mounting structure 303, the bolt-shaped conductor 315 is inserted into the two intervening coupling fittings 314 and the insulating cases 311a and 311b from the one interposing coupling fitting 314 side, and the insertion hole of the other intervening coupling fitting 314 is inserted. The insulating cases 311 a and 311 b are fixed by attaching and tightening nuts 316 to the protruding portions 315 b of the bolt-shaped conductors 315 protruding from 322. In this case, the head on the base end side of the bolt-shaped conductor 315 protrudes from one of the interposed coupling fittings 314, and the distal end of the bolt-shaped conductor 315 projects from the other interposed coupling fitting 314. The amount of protrusion is generally different. Further, the protruding amount of the tip end portion of the bolt-shaped conductor 315 also changes depending on the tightening strength of the nut 316.

  For this reason, in this mounting structure, for example, when it is determined in advance that the bolt-shaped conductor 315 is inserted from one of the two interposed coupling fittings 314 toward the other, When the bolt-shaped conductor 315 is inserted from the other side of the connecting fitting 314 toward the other side, the conductive portion existing in the chassis 410 from the end of the bolt-shaped conductor 315 (the end located on the lower side in FIG. 10). The distance (insulation distance (spatial distance)) up to 430 (see the same figure) is different from the design value. Here, the standard (for example, IEC61010-1 etc.) stipulates that the insulation distance from each end portion of the bolt-shaped conductor 315 to the conductive portion 430 is a predetermined insulation distance or more (mandatory) In this case, if the insertion direction of the bolt-shaped conductor 315 is wrong as described above, there is a possibility that the prescribed insulation distance cannot be secured, and improvement of this point is desired. In this mounting structure, the insulating cases 311a and 311b are fixed by tightening the nut 316 attached to the tip of the bolt-shaped conductor 315. In this case, in this configuration, since it is necessary to rotate the at least one of the both while preventing the rotation of both by engaging the tool with both the head of the bolt-shaped conductor 315 and the nut 316, workability is improved. Unfortunately, improvement of this point is also desired.

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide an attachment mechanism and a measuring apparatus that can ensure a prescribed insulation distance while improving workability.

In order to achieve the above object, the attachment mechanism according to claim 1 is an attachment mechanism for attaching a current detection part having an insertion hole in a central part to an attachment target, and is configured to be fitted to each other in a fitted state. A pair of cases in which the current detection unit is accommodated and an opening facing the insertion hole is formed in the center, the opening of each case, and the insertion hole of the current detection unit accommodated in each case And a conductor that conducts the current to be measured, and each end of the conductor is connected to each end, and each base end is attached to the attachment object to support the conductor. And a pair of support members that supply the current to be measured to the conductor, and connecting members that connect the tip portions of the support members and the end portions of the conductor, respectively, , Crossing Each end is formed with a non-circular columnar shape, and a screw hole is provided at each end, and the opening of each case can regulate the rotation of the conductor inserted through the opening. Each of the support members is formed in a shape, and the front end portion is formed in a rectangular shape, and the front end portion is provided with a connection hole, and the connection member is used for the connection of the support members. It is composed of a pair of screws that can be inserted into the holes and screwed into the screw holes of the conductor, and the three end surfaces of the tip of the support member can be pressed against each main surface of each case. A rib that is formed in a U shape in plan view and positions the tip is provided .

  According to a second aspect of the present invention, in the attachment mechanism according to the first aspect, the opening of each case is formed in a shape complementary to the cross-sectional shape of the conductor.

  The attachment mechanism according to claim 3 is the attachment mechanism according to claim 1 or 2, wherein the connecting member is constituted by a countersunk screw.

  According to a fourth aspect of the present invention, there is provided the attachment mechanism according to the third aspect, wherein a head of the countersunk screw can be brought into contact with an edge of the connection hole at the tip of each support member. An inclined surface is formed.

  According to a fifth aspect of the present invention, there is provided a measuring apparatus comprising: the mounting mechanism according to any one of the first to fourth aspects; a housing as the mounting target; and the current detection unit attached to the housing by the mounting mechanism. And measuring the current value of the current to be measured.

  The mounting mechanism according to claim 1 and the measuring device according to claim 5, wherein the cross-sectional shape of the conductor is formed in a non-circular column shape, a screw hole is provided at each end of the conductor, and each support The tip of each support member and each end of the conductor are connected by a pair of screws that are inserted through the connecting holes of the member and can be screwed into the screw holes of the conductor. For this reason, in this attachment mechanism and measuring device, unlike the configuration in which a bolt is inserted into the opening of each case and the tip of each support member and a nut is attached to the tip of the bolt and tightened, The projecting amounts of the screws can be made the same projecting amount. For this reason, according to this attachment mechanism and the measurement device, for example, an intermediate position between the top plate and the bottom plate of the housing of the measurement device (a central portion in the thickness direction of the housing) and the upper and lower positions of the attachment mechanism in the attachment state When the mounting mechanism is arranged so that the central portion in the direction is positioned at the same height, the distance from each screw (the protruding portion of each screw) to the housing can be maintained at the same distance. As a result, according to the mounting mechanism and the measuring apparatus, it is possible to reliably ensure the insulation distance (spatial distance) defined in a predetermined standard.

  Further, according to this attachment mechanism and the measuring apparatus, the opening of the conductor inserted into the opening of each case is formed in a shape that can restrict the rotation of the conductor, so that the conductor can be rotated along with the rotation of the screw. Therefore, without engaging the tool with the conductor, by holding the case through which the conductor is inserted and rotating the screw, the tip of each support member and each end of the conductor Can be linked. Therefore, according to the attachment mechanism and the measuring apparatus, it is possible to ensure a prescribed insulation distance while improving the workability of the attachment work of the current detection unit.

  Further, according to the mounting mechanism according to claim 2 and the measuring device according to claim 5, the rotation of the screw is achieved by forming the opening of each case in a shape complementary to the cross-sectional shape of the conductor. As a result, it is possible to more reliably prevent the electric conductor from being turned around, so that the workability of the mounting operation of the current detector can be further improved.

  Moreover, in the attachment mechanism according to claim 3 and the measuring device according to claim 5, the connecting member is constituted by a countersunk screw, so that the head is compared with a configuration using bolts (such as cap screws) as the connecting member. The countersunk screw (head) protrudes from each support member when it is screwed into the screw hole of the conductor and the tip of each support member is connected to each end of the conductor. The amount can be reduced. For this reason, according to this attachment mechanism and measuring device, a longer insulation distance (spatial distance) can be ensured compared to a configuration using bolts (cap screws or the like) as connecting members.

  Further, in the attachment mechanism according to claim 4 and the measuring device according to claim 5, an inclined surface on which the lower surface of the head of the countersunk screw can be brought into contact with the edge of the connection hole at the tip of the support member is formed. Thus, when the countersunk screw is screwed into the screw hole of the conductor, a part or all of the head can be buried in the connecting hole. For this reason, according to this attachment mechanism and measuring device, the amount of protrusion of the countersunk screw (head) from each support member when the tip end of each support member and each end of the conductor are connected to each other is inclined. As a result, the insulation distance (spatial distance) can be further ensured.

1 is a configuration diagram showing a configuration of a current measuring device 100. FIG. FIG. 6 is a side view showing a state in which the attachment mechanism 3 is attached to the terminal block 120. It is a perspective view which shows the state which attached the attachment mechanism 3 to the terminal block 120. FIG. It is a side view of the attachment mechanism 3, the current detection part 1, and the terminal block 120 in a disassembled state. It is the perspective view of the attachment mechanism 3, the electric current detection part 1, and the terminal block 120 which were decomposed | disassembled in the state which turned the case 11a up. It is the perspective view of the attachment mechanism 3, the electric current detection part 1, and the terminal block 120 which were decomposed | disassembled in the state which turned the case 11b up. 3 is a first configuration diagram showing a configuration of an attachment mechanism 103. FIG. FIG. 6 is a second configuration diagram showing the configuration of the attachment mechanism 103. 3 is a configuration diagram showing a configuration of an attachment mechanism 203. FIG. It is a side view which shows the structure of the conventional attachment mechanism 303. FIG. It is a side view which shows the structure of the conventional attachment mechanism 303. FIG.

  Hereinafter, embodiments of an attachment mechanism and a measuring device will be described with reference to the accompanying drawings.

  First, the configuration of the current measuring apparatus 100 shown in FIG. 1 will be described with reference to the drawings. The current measuring device 100 is an example of a measuring device, and as shown in the figure, includes a current detecting unit 1 and a measuring unit 2, and is configured to be able to measure the current value of the current to be measured. In addition, the current measuring device 100 includes a housing 110 (a part of which is shown in FIG. 2) that houses each component of the current measuring device 100 including the current detecting unit 1 and the measuring unit 2. Terminal block 120 having an input terminal 121 for inputting a current to be measured (input terminal portion: see FIGS. 2 and 3), and an attachment mechanism for attaching the current detection unit 1 to the terminal block 120 as an attachment target 3 (see both figures).

  The current detector 1 is a through-type current transformer (CT (Current Transformer)) as an example, and includes an annular magnetic core (iron core) and a coil formed by winding a conductive wire around the magnetic core. 4-6, it is comprised by the planar view cyclic | annular form (doughnut shape) which has the penetration hole 1a in the center part. Further, as shown in FIG. 2, the current detection unit 1 is attached to the housing 110 while being supported by the attachment mechanism 3.

  The measurement unit 2 is composed of electronic components such as a CPU mounted on a substrate housed in the housing 110, and measures the current value of the current to be measured based on the detection signal output from the current detection unit 1. The current value is displayed on the display unit outside the figure.

  2 to 6, the attachment mechanism 3 includes a case 11a and a case 11b (corresponding to a pair of cases, hereinafter also referred to as “case 11” when the cases 11a and 11b are not distinguished from each other). A material 12, a conductor 13, a pair of bus bars 14, and a pair of bolts 15 are provided.

  As shown in FIGS. 2 and 3, the cases 11 are configured to be fitted to each other and accommodate the current detection unit 1 in the fitted state. Moreover, as shown in FIGS. 4-6, the cylindrical part 21 which has the opening part (insertion hole) 22 is formed in the center part of each case 11, respectively. These cylindrical portions 21 are connected to each other when the cases 11 are fitted. In this case, each cylindrical part 21 has a function of insulating the current detection part 1 accommodated in the case 11 and the conductor 13 inserted through the opening 22. In addition, in a state where each case 11 accommodates and fits the current detection unit 1, each cylindrical portion 21 is inserted (inserted) into the insertion hole 1 a of the current detection unit 1. The opening 22 is in a state facing the insertion hole 1a.

  In this case, as shown in FIG. 5, for example, the cross-sectional shape of the opening 22 is formed in a hexagonal shape that allows the conductor 13 to be inserted and restricts the rotation of the inserted conductor 13. . That is, the opening 22 has a cross-sectional shape (planar shape) that is complementary to the cross-sectional shape of the conductor 13.

  As shown in FIGS. 4 to 6, the main surface 23 of the case 11 is provided with a rib 24 for positioning the front end portion 14 a of the bus bar 14. 5 and 6, the side surface 25 of the case 11a is provided with a notch 26, and the side surface 25 of the case 11b is fitted into the notch 26 in a state in which both cases 11a and 11b are fitted. A convex portion 27 is provided. In this case, the length of the notch 26 is such that the protrusion 27 can form a gap for drawing out the conducting wire 1b for outputting an electric signal from the current detection unit 1 in the fitted state with the notch 26. The length is shorter than (the vertical length in FIGS. 5 and 6).

  Each buffer material 12 is formed in a planar plate-like plate shape having an insertion hole 12a in the center, and as shown in FIGS. 4 to 6, between the top surface of the case 11a and the current detection unit 1, and It is each arrange | positioned between the bottom face of case 11b, and the electric current detection part 1. FIG. The cushioning material 12 is formed of a flexible material, and has a function of absorbing the impact applied to the case 11 and restricting the movement of the current detection unit 1 accommodated in each case 11.

  As shown in FIGS. 5 and 6, the conductor 13 is formed in a columnar shape having a hexagonal shape (an example of a non-circular shape) using a conductive material (for example, brass) as shown in FIGS. Further, screw holes 33 into which screw portions 15b of bolts 15 to be described later are screwed are provided in the end portions 13a and 13b of the conductor 13. The conductor 13 is inserted into the opening 22 of the cylindrical portion 21 (that is, the insertion hole 1 a of the current detection unit 1) in each case 11 in which the current detection unit 1 is accommodated, and the input terminal 121 of the terminal block 120. The current to be measured that is input through the bus bar 14 is conducted into the insertion hole 1a of the current detection unit 1.

  Each bus bar 14 is an example of a support member, and is formed using a conductive plate-like material (for example, a plate made of brass). As shown in FIGS. 4 and 5, a connecting hole 41 is formed at the tip end portion 14 a of the bus bar 14 so that the screw portion 15 b of the bolt 15 can be inserted and the conductor 13 cannot be inserted. . The base end portion 14b of the bus bar 14 is formed with a fixing hole 42 through which the screw portion 122a (see FIGS. 2 and 4) of the fixing screw 122 screwed into the input terminal 121 of the terminal block 120 can be inserted. Yes.

  In this case, each of the bus bars 14 has a front end portion 14a bolted to the end portions 13a and 13b of the conductor 13 inserted through the opening portion 22 (the insertion hole 1a of the current detection portion 1) of the cylindrical portion 21 in the case 11. 15 are connected to each other. Further, each bus bar 14 is fixed to a terminal block 120 having a base end portion 14 b disposed in the housing 110 by a fixing screw 122. The bus bar 14 has a function of supporting each part of the current detection unit 1 and the attachment mechanism 3 and attaching the current bar to the terminal block 120, and the measurement target current input to the input terminal 121 of the terminal block 120 to the conductor 13. It has a function of conducting (supplying).

  Each bolt 15 is an example of a screw as a connecting member, and has a head 15a formed in a columnar shape and a cross-sectional shape formed of a cap screw provided with a hexagonal hole in the head 15a. . The bolt 15 is configured such that the screw portion 15b inserted through the connection hole 41 of the bus bar 14 is screwed into the screw hole 33 of the conductor 13, whereby the tip portion 14a of each bus bar 14 and the end portions 13a and 13b of the conductor 13 are provided. Have the function of connecting

  Next, a procedure for attaching the current detection unit 1 to the terminal block 120 disposed in the casing 110 of the current measuring device 100 using the attachment mechanism 3 will be described with reference to the drawings.

  First, as shown in FIG. 2, the screw portion 122 a of the fixing screw 122 is inserted into the fixing hole 42 formed in the base end portion 14 b of each bus bar 14, and then disposed in the housing 110. Screw portion 122 a is screwed into input terminal 121 of terminal block 120. As a result, the base end portion 14 b of the bus bar 14 is fixed to the terminal block 120.

  Subsequently, the current detection unit 1 is accommodated in the case 11a and the case 11b. Specifically, as shown in FIGS. 4 to 6, the current detection unit 1 is sandwiched between a pair of cushioning members 12, and the case 11 a and the case 11 b are brought close to each other from above and below the current detection unit 1 to be fitted to each other. Let At this time, the notch 26 of the case 11a and the convex portion 27 of the case 11b are fitted together, and the conducting wire 1b is pulled out from the gap between them.

  Next, the conductor 13 is inserted through the opening 22 of the cylindrical portion 21 in each case 11. In this case, since the cross-sectional shape of the opening 22 is formed in the same hexagon (complementary shape) as the cross-sectional shape of the conductor 13, the rotation of the conductor 13 inserted through the opening 22 is restricted. Is done.

  Subsequently, the front end portion 14a of one bus bar 14 is brought into contact with the main surface 23 of one case (for example, the case 11a) of each case 11, and the other bus bar is contacted with the main surface 23 of the other (case 11b) of each case 11. 14 tip portions 14a are brought into contact with each other. At this time, positioning is performed by pressing the end surface of each tip portion 14 a against the rib 24 provided on each main surface 23. Next, the threaded portion 15b of the bolt 15 is inserted into the connecting hole 41 from the outer surface side (the upper surface side in FIGS. 4 and 5) of the front end portion 14a of one bus bar 14. Subsequently, the bolt 15 is rotated using a tool, and the screw portion 15 b is screwed into the screw hole 33 provided in the end portion 13 a of the conductor 13.

  Thereby, the front-end | tip part 14a of one bus-bar 14 and the edge part 13a of the conductor 13 are connected. In this case, in this attachment mechanism 3, as described above, the rotation of the conductor 13 is restricted. For this reason, the rotation of the electric conductor 13 accompanying the rotation of the bolt 15 is prevented, and the bolt 15 is rotated by holding each case 11 through which the electric conductor 13 is inserted without engaging a tool with the electric conductor 13. Thus, it is possible to connect the end portion 14 a of the bus bar 14 and the end portion 13 a of the conductor 13.

  Next, the threaded portion 15 b of the bolt 15 is inserted into the connecting hole 41 from the outer surface side (the lower surface side in FIGS. 4 and 5) of the tip end portion 14 a of the other bus bar 14. Thereafter, the screw portion 15 b is screwed into the screw hole 33 of the end portion 13 b of the conductor 13. Thereby, the front-end | tip part 14a of the other bus-bar 14 and the edge part 13b of the conductor 13 are connected. Thereby, each case 11 in which the current detection unit 1 is accommodated is supported by the distal end portions 14 a of the pair of bus bars 14. Thus, the attachment of the current detection unit 1 is completed.

  Here, in this attachment mechanism 3, the screw portion 15 b of the bolt 15 is screwed into each screw hole 33 of the conductor 13 in which the screw holes 33 are formed in the end portions 13 a and 13 b, and the tip portion 14 a of the bus bar 14 and the conductor 13 are connected. The structure which connects edge part 13a, 13b is employ | adopted. For this reason, in this attachment mechanism 3, a bolt is inserted into the opening 22 of each case 11 and the tip 14a of each bus bar 14, and a nut is attached to the tip of the bolt and tightened. As shown, the projecting amounts of the bolts 15 (the head portions 15a of the bolts 15) from the bus bars 14 can be the same projecting amounts. For this reason, in this attachment mechanism 3, for example, an intermediate position between the top plate and the bottom plate of the housing 110 (a central portion in the thickness direction of the housing 110), and a vertical central portion of the attachment mechanism 3 in the attached state. When the mounting mechanism 3 is arranged so that the positions of the bolts 15 are approximately the same, the distances from the heads 15a of the bolts 15 to the housing 110 can be maintained at the same distance. As a result, in this attachment mechanism 3, it is possible to reliably ensure an insulation distance (spatial distance) defined in a predetermined standard (for example, IEC61010-1).

  Next, a method for measuring the current value of the current to be measured using the current measuring device 100 and the operation of the current measuring device 100 at that time will be described with reference to the drawings.

  When measuring the current value of the current to be measured using the current measuring device 100, the terminal block 120 provided on the casing 110 of the current measuring device 100 has an input lead for inputting the current to be measured. To the input terminal 121. Subsequently, the operation unit (not shown) is operated to support the start of measurement, and the current to be measured is conducted to the input conductor.

  At this time, the current to be measured input from the input terminal 121 is supplied via the bus bar 14 to the conductor 13 inserted through the insertion hole 1 a of the current detection unit 1. Further, the current detection unit 1 detects the current to be measured that conducts the conductor 13, and outputs a detection signal to the measurement unit 2 through the lead 1b. Next, the measurement unit 2 measures the value of the measurement target current based on the detection signal output from the current detection unit 1. Then, the measurement part 2 displays the measured electric current value on the display part outside a figure.

  As described above, in the attachment mechanism 3 and the current measuring device 100, the cross-sectional shape of the conductor 13 is formed in a hexagonal (non-circular) columnar shape, and the screw holes 33 are formed in the end portions 13 a and 13 b of the conductor 13. Are provided, and a pair of bolts 15 that are inserted into the connection holes 41 of the bus bars 14 and can be screwed into the screw holes 33 of the conductors 13, and the end portions 14 a of the bus bars 14 and the end portions 13 a and 13 b of the conductors 13. Are connected. For this reason, in this attachment mechanism 3 and the current measuring device 100, a configuration in which a bolt is inserted into the opening 22 of each case 11 and the tip 14a of each bus bar 14 and a nut is attached to the tip of the bolt and tightened. Unlikely, the protruding amount of the bolt 15 from each bus bar 14 can be made the same protruding amount. Therefore, according to the attachment mechanism 3 and the current measuring device 100, for example, an intermediate position between the top plate and the bottom plate of the housing 110 (the central portion in the thickness direction of the housing 110) and the attachment mechanism in the attached state. When the mounting mechanism 3 is arranged so that the vertical center of 3 is located at the same height, the distance from each bolt 15 (the protruding portion of each bolt 15) to the housing 110 is the same distance. Can be maintained. As a result, according to the mounting mechanism 3 and the current measuring device 100, it is possible to reliably ensure the insulation distance (spatial distance) defined in a predetermined standard.

  Further, according to the mounting mechanism 3 and the current measuring device 100, each opening 22 is formed in a shape capable of restricting the rotation of the conductor 13 inserted through the opening 22 of each case 11, so that the bolt 15 By rotating the bolts 15 with the respective cases 11 through which the conductors 13 are inserted without engaging the tools with the conductors 13, the rotation of the conductors 13 can be prevented. The front end portion 14a of the bus bar 14 and the end portions 13a and 13b of the conductor 13 can be connected. Therefore, according to the attachment mechanism 3 and the current measuring device 100, it is possible to ensure a prescribed insulation distance while improving the workability of the attachment work of the current detection unit 1.

  Further, according to the mounting mechanism 3 and the current measuring device 100, the opening 22 of each case 11 is formed in a shape complementary to the cross-sectional shape of the conductor 13, so Since the rotation of the body 13 can be more reliably prevented, the workability of the mounting operation of the current detection unit 1 can be further improved.

  In addition, the structure of an attachment mechanism and a mounting board | substrate is not limited to said structure. For example, instead of the mounting mechanism 3 described above, the mounting mechanism 103 shown in FIG. 7 may be employed. In addition, in the following description, about the same component as the above-mentioned attachment mechanism 3, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  As shown in FIG. 7, the attachment mechanism 103 has a flat head 115 a having a flat upper surface and a flat head 115 a having a tapered lower surface as a connecting member, instead of the bolt 15 described above. It is used. Further, in this attachment mechanism 103, as shown in the figure, a bus bar 114 is used instead of the bus bar 14 described above. In this case, a connecting hole 141 is formed at the front end portion 114a of the bus bar 114, and an inclined surface 141a with which the lower surface of the head 115a of the countersunk screw 115 can be abutted is formed at the edge of the connecting hole 141. Has been.

  In this attachment mechanism 103, since the countersunk screw 115 as the connecting member is employed, the thickness (height) of the head 115a is smaller than that of the bolt 15 (cap screw), so that the screw hole 33 of the conductor 13 is formed. The amount of protrusion of the countersunk screw 115 (head 115a) from each bus bar 114 when the front end portion 114a of each bus bar 114 and the end portions 13a and 13b of the conductor 13 are connected by screwing can be reduced. For this reason, according to this attachment mechanism 103, a longer insulation distance (spatial distance) can be ensured. In this case, even in a configuration in which the inclined surface 141a is not formed at the edge of the connection hole 141, the thickness of the head 115a of the countersunk screw 115 is thinner than the thickness of the head 15a of the bolt 15, so that this effect is realized. can do.

  Further, in this attachment mechanism 103, an inclined surface 141a with which the lower surface of the head portion 115a of the countersunk screw 115 can abut on the edge portion of the connecting hole 141 in the distal end portion 114a of the bus bar 114 is shown in FIG. As described above, when the countersunk screw 115 is screwed into the screw hole 33 of the conductor 13, a part or all of the head portion 115 a can be buried in the connection hole 141. For this reason, according to this attachment mechanism 103, the amount of protrusion of the countersunk screw 115 (head 115a) from the bus bar 114 when the front end portion 114a of the bus bar 114 and the end portions 13a and 13b of the conductor 13 are connected is determined. As a result of being able to further reduce compared with the structure which does not form the inclined surface 141a, a still longer insulation distance (spatial distance) can be ensured.

  Moreover, the attachment mechanism 203 shown in FIG. 9 can also be employ | adopted. In this attachment mechanism 203, as shown in the figure, the cross section of the current detector 1 (the main surface 23 of each case 11a, 11b) is in a posture that makes a right angle to the bottom surface 110a and the top surface 110b of the housing 110. It is supported by two bus bars 214 as support members. In this case, the attachment mechanism 203 is formed so that the base end portion 214b of the bus bar 214 faces outward. For this reason, when the current detection unit 1 is attached to the housing 110 using the attachment mechanism 203, the end portions 214a of the bus bars 214 are connected to the end portions 13a and 13b of the conductor 13, respectively (each It is also possible to fix the base end portion 214b of each bus bar 214 to the housing 110 using the fixing screw 122 after the case 11 is supported by the tip end portion 214a. In addition, the same code | symbol is attached | subjected to what has the same function as each component of the attachment mechanism 3, and the overlapping description is abbreviate | omitted.

  Moreover, although it described above about the example using the conductor 13 formed in a hexagonal columnar cross-sectional shape, the cross-sectional shape of the conductor 13 is not limited to a hexagon, for example, an ellipse, a polygon other than a hexagon, It can be formed in any other shape other than circular. In addition, the cross-sectional shape (planar shape) of the opening 22 can be formed in any shape complementary to the cross-sectional shape of the conductor 13.

  Furthermore, as long as the rotation of the conductor 13 inserted through the opening 22 can be regulated, the cross-sectional shape (plan view shape) of the opening 22 is formed in a shape different from the cross-sectional shape of the conductor 13. You can also. As an example, the cross-sectional shape of the conductor 13 is formed in a hexagon and the cross-sectional shape of the opening 22 is formed in a quadrangle, or the cross-sectional shape of the conductor 13 is formed in a quadrangle and the cross-section of the opening 22 is formed. The shape can be formed in a hexagon.

  Further, the example using the case 11 provided with the cylindrical portion 21 has been described above. However, when the current detection portion 1 and the conductor 13 are reliably insulated, the main surface 23 is not provided without providing the cylindrical portion 21. It is also possible to employ a configuration using the case 11 provided with an opening 22 in the case.

DESCRIPTION OF SYMBOLS 1 Current detection part 1a Insertion hole 2 Measuring part 3,103,203 Attachment mechanism 11a, 11b Case 13 Conductor 13a, 13b End part 14, 114, 214 Bus bar 14a, 114a, 214a End part 14b, 214b Base end part 15 Bolt 22 opening 33 screw hole 41, 141 connecting hole 100 current measuring device 110 housing 115 countersunk screw 115a head 141a inclined surface

Claims (5)

An attachment mechanism for attaching a current detection part having an insertion hole in the center part to an attachment object,
A pair of cases that are configured to be fitted to each other, accommodate the current detection unit in a fitted state and have an opening facing the insertion hole formed in the center, and the opening of each case and each case A conductor that is inserted into the insertion hole of the current detection unit housed in the current passage to conduct a current to be measured, and each distal end is connected to each end of the conductor, and each base end is A pair of support members that are attached to an attachment target to support the conductor and supply the current to be measured to the conductor, and the tip end portions of the support members and the end portions of the conductors, respectively. A connecting member to be connected,
The conductor is formed in a columnar shape with a non-circular cross-sectional shape and provided with a screw hole at each end,
The opening of each case is formed in a shape that can regulate the rotation of the conductor inserted through the opening,
Each of the support members is formed with a rectangular shape at the tip portion, and the tip portion is provided with a connecting hole,
The connecting member is composed of a pair of screws that are inserted into the connecting holes of the support members and can be screwed into the screw holes of the conductor, respectively .
A mounting mechanism in which each main surface of each case is provided with a rib that is formed in a U-shape in a plan view and can position the front end portion so as to press three end surfaces of the front end portion of the support member .   The attachment mechanism according to claim 1, wherein the opening of each case is formed in a shape complementary to a cross-sectional shape of the conductor.   The attachment mechanism according to claim 1, wherein the connecting member is constituted by a countersunk screw.   The attachment mechanism according to claim 3, wherein an inclined surface with which a head of the flat head screw can be contacted is formed at an edge portion of the connection hole at the distal end portion of each support member.   A current value of the current to be measured, comprising: the attachment mechanism according to any one of claims 1 to 4; a casing as the attachment target; and the current detection unit attached to the casing by the attachment mechanism. Measuring device to measure.

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