Bus bar unit

A bus bar unit related to one aspect includes: a first bus bar and a second bus bar. The first bus bar and the second bus bar are arranged side by side in a second direction orthogonal to a first direction as viewed from the first direction. The first bus bar includes, as viewed from the first direction, a first straight line portion, a first inclined portion, and a first bent portion. The second bus bar includes, as viewed from the first direction, a second straight line portion, a second inclined portion, and a second bent portion. In an end surface on a second bus bar side of the first bent portion, a distance between the first bent portion and the second inclined portion is longer than a distance between the first bent portion and the second straight line portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2019-031952 filed on Feb. 25, 2019, the contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a bus bar unit including a plurality of bus bars.

BACKGROUND ART

Conventionally, a rotary electric machine is mounted as a drive source in an electric vehicle or the like. Further, there has been known that a bus bar unit including a plurality of bus bars is used as a component that electrically connects the rotary electric machine and a power conversion device for supplying electric power to the rotary electric machine.

In the bus bar unit, in a case in which a length of the bus bar is long, an influence of a manufacturing error or the like on the bus bar is increased. When terminal portions at both ends of the bus bar are connected to the rotary electric machine and a control device, the bus bar may be deformed and the adjacent bus bars may come into contact with each other to cause a short circuit.

As a bus bar unit that prevents the adjacent bus bars from coming into contact with each other, for example, Patent Literature 1 (JP-A-2018-038129) discloses a bus bar unit including a mold portion that molds an entire circumference of at least one bus bar with a resin or the like.

However, the bus bar unit of Patent Literature 1 requires cost and a manufacturing process for forming the mold portion.

Therefore, in the bus bar unit, it is more desirable that an insulation distance between the adjacent bus bars is ensured regardless of the mold portion or the like.

The present invention provides a bus bar unit that can ensure an insulation distance between adjacent bus bars and prevent the adjacent bus bars from coming into contact with each other and causing a short circuit.

SUMMARY

A bus bar unit related to one aspect includes: a first bus bar and a second bus bar that have a flat plate shape. The first bus bar and the second bus bar are arranged side by side in a second direction orthogonal to a first direction as viewed from the first direction. The first bus bar includes, as viewed from the first direction, a first straight line portion extending linearly in a third direction orthogonal to the second direction, a first inclined portion extending linearly on a side opposite to a side where the second bus bar is arranged in the second direction with respect to the first straight line portion, as a distance from the first straight line portion increases in the third direction, and a first bent portion connecting the first straight line portion and the first inclined portion. The second bus bar includes, as viewed from the first direction, a second straight line portion arranged on the same plane as the first straight line portion and extending linearly substantially parallel to the first straight line portion, a second inclined portion arranged on the same plane as the first inclined portion and extending linearly substantially parallel to the first inclined portion, and a second bent portion arranged on the same plane as the first bent portion and connecting the second straight line portion and the second inclined portion. In an end surface on a second bus bar side of the first bent portion, a distance between the first bent portion and the second inclined portion is longer than a distance between the first bent portion and the second straight line portion.

According to the present invention, an insulation distance between the first bus bar and the second bus bar can be ensured, and the first bus bar and the second bus bar can be prevented from coming into contact with each other and causing a short circuit.

DESCRIPTION OF EMBODIMENTS

Hereinafter, an embodiment of a bus bar unit according to the present invention will be described with reference to the accompanying drawings.

As shown inFIGS. 1 and 2, a bus bar unit1includes three bus bars10U,10V, and10W, and a cover member30that collectively covers the three bus bars10U,10V, and10W.

In this specification, in order to simplify the description, front, rear, left, right, upper and lower directions of the bus bar unit1are defined as shown in the drawings, and a front direction thereof is indicated by Fr, a rear direction thereof is indicated by Rr, a right direction thereof is indicated by R, a left direction thereof is indicated by L, an upper direction is indicated by U, and a lower direction is indicated by D, respectively. However, the directions shown in the drawing are independent of directions of a device or the like on which the bus bar unit1is mounted.

The three bus bars10U,10V, and10W have a flat plate shape extending from a first terminal block51to a second terminal block52arranged on a lower left side of the first terminal block51.

The three bus bars10U,10V, and10W include first terminal portions21U,21V, and21W having a flat surface substantially perpendicular to an upper-lower direction and fixed to the first terminal portion51, first extending portions110U,110V, and110W extending downward from front ends of the first terminal portions21U,21V, and21W, second extending portions120U,120V, and120W extending forward from lower ends of the first extending portions110U,110V, and110W, third extending portions130U,130V, and130W extending leftward from front ends of the second extending portions120U,120V, and120W, fourth extending portions140U,140V, and140W extending downward from left ends of the third extending portions130U,130V, and130W, fifth extending portions150U,150V, and150W extending forward from lower ends of the fourth extending portions140U,140V, and140W, and second terminal portions22U,22V, and22W provided at front ends of the fifth extending portions150U,150V, and150W and having a flat surface substantially perpendicular to a front-rear direction, respectively.

The three bus bars10U,10V, and10W are arranged such that the extending portions110U to150U,110V to150V, and110W to150W extend in parallel to each other.

The arrangement of the three bus bars10U,10V, and10W can be set as appropriate, but in the present embodiment, the first terminal portions21U,21V, and21W, the first extending portions110U,110V, and110W, and the second extending portions120U,120V,120W are arranged in this order from the right to the left, the third extending portions130U,130V, and130W, and the fourth extending portions140U,140V, and140W are arranged in this order from the front to the rear, and the fifth extending portions150U,150V, and150W, and the second terminal portions22U,22V, and22W are arranged in this order from the top to the bottom.

The first terminal portions21U,21V, and21W are provided with bolt insertion holes211U,211V, and211W on a plane substantially perpendicular to the upper-lower direction. The first terminal portions21U,21V, and21W are fastened to the first terminal block51by bolts921U,921V, and921W inserted into the bolt insertion holes211U,211V, and211W, respectively. Further, the first terminal portions21U,21V, and21W are electrically connected to, for example, a power conversion device (not shown) in each phase of a U-phase, a V-phase, and a W-phase via the first terminal block51.

The second terminal portions22U,22V, and22W are provided with bolt insertion holes221U,221V, and221W on a plane substantially perpendicular to the front-rear direction. The second terminal portions22U,22V, and22W are fastened to the second terminal block52by bolts922U,922V, and922W inserted into the bolt insertion holes22W,221V, and221W, respectively. Further, the second terminal portions22U,22V, and22W are electrically connected to, for example, coils (not shown) of a rotary electric machine in each phase of a U-phase, a V-phase, and a W-phase via the second terminal block52.

Since the three bus bars10U,10V, and10W include the first extending portions110U,110V, and110W and the fourth extending portions140U,140V, and140W extending in the upper-lower direction, the second extending portions120U,120V, and120W and the fifth extending portions150U,150V, and150W extending in the front-rear direction, and the third extending portions130U,130V, and130W extending in a left-right direction, the three bus bars10U,10V, and10W extend in three directions perpendicular to each other.

Therefore, when the first terminal portions21U,21V, and21W and the second terminal portions22U,22V, and22W are respectively fastened to the first terminal block51and the second terminal block52, even if there is a manufacturing error in the bus bars10U,10V, and10W, stress can be distributed in the three directions perpendicular to each other at the extending portions extending in the upper-lower direction, the front-rear direction, and the left-right direction.

The cover member30includes a cover base31attached to a case (not shown) of the rotary electric machine, and a cover portion32that is held by the cover base31and covers the three bus bars10U,10V, and10W, for example.

The cover base31is provided with bolt insertion holes311. In the present embodiment, the pair of bolt insertion holes311are provided at both left and right ends of the cover base31. The cover base31is fixed to, for example, the case (not shown) of the rotary electric machine by bolts931inserted into the pair of bolt insertion holes311.

The cover portion32covers the second extending portions120U,120V, and120W and a portion of a right end side of the third extending portions130U,130V, and130W of the three bus bars10U,10V, and10W. The three bus bars10U,10V, and10W are arranged side by side on the same plane inside the cover member30.

In this way, since the bus bars10U,10V, and10W are configured such that the second extending portions120U,120V, and120W extending in the left-right direction, and a portion of the right end side of the third extending portions130U,130V, and130W extending in the left-right direction are covered by the cover portion32, even if the bus bars10U,10V, and10W are relatively moved in the front-rear direction, the left-right direction, and the upper-lower direction, the bus bars10U,10V, and10W are caught by the cover portion32, and do not fall off from the cover portion32. Therefore, after the bus bar unit1is assembled, the three bus bars10U,10V, and10W can be handled as one body by the cover member30.

The cover member30is configured to not come into contact with the three bus bars10U,10V, and10W, for example, in a state of being attached to the case of the rotary electric machine. Accordingly, even when the bus bars10U,10V, and10W vibrate, generation of abnormal noise due to contact between the bus bars10U,10V, and10W and the cover member30can be prevented.

The three bus bars10U,10V, and10W are not fixed to the cover member30, and can move to some extent within the cover member30. Accordingly, even if there is the manufacturing error in the bus bars10U,10V, and10W, the first terminal portions21U,21V, and21W, and the second terminal portions22U,22V, and22W can be easily fastened to the first terminal block51and the second terminal block52, respectively.

As shown inFIGS. 2 and 3, the third extending portions130U,130V, and130W of the bus bars10U,10V, and10W are arranged in this order from the front to the rear as viewed from above.

The third extending portions130U,130V, and130W include, as viewed from above, right straight line portions131U,131V, and131W extending linearly in the left-right direction from a right end, forward inclined portions132U,132V, and132W that are arranged at left sides of the right straight line portions131U,131V, and131W, and are inclined forward and extend linearly from a right side toward a left side, and left straight line portions133U,133V, and133W that are arranged at left sides of the forward inclined portions132U,132V, and132W, and extend linearly in the left-right direction, and left ends of the left straight line portions133U,133V, and133W are left ends of the third extending portions130U,130V, and130W, respectively.

Left ends of the right straight line portions131U,131V, and131W and right ends of the forward inclined portions132U,132V, and132W are connected by right bent portions134U,134V, and134W, and left ends of the forward inclined portions132U,132V, and132W and right ends of the left straight line portions133U,133V, and133W are connected by left bent portions135U,135V, and135W, respectively.

The right straight line portions131U,131V, and131W include, as viewed from the front, upper straight line portions131aU,131aV, and131aW extending in the left-right direction from the right end, downward inclined portions131bU,131bV, and131bW that are inclined downward and extend linearly toward the left side from left ends of the upper straight line portions131aU,131aV, and131aW, and lower straight line portions131cU,131cV, and131cW extending in the left-right direction from left ends of the downward inclined portions131bU,131bV,131bW, and left ends of the lower straight line portions131cU,131cV, and131cW are the left ends of the right straight line portions131U,131V, and131W, respectively.

The right straight line portions131U,131V, and131W are arranged on the same plane and extend substantially parallel to each other. More specifically, the upper straight line portions131aU,131aV, and131aW are arranged on the same plane perpendicular to the upper-lower direction and extend substantially parallel to each other, and the lower straight line portions131cU,131cV, and131cW are arranged on the same plane perpendicular to the upper-lower direction and extend substantially parallel to each other. In addition, the downward inclined portions131bU,131bV, and131bW extend at the same angle of inclination and are formed side by side in the front-rear direction, at the same position in the left-right direction.

The forward inclined portions132U,132V, and132W are arranged on the same plane and extend substantially parallel to each other. The right bent portions134U,134V, and134W are arranged on the same plane. The left straight line portions133U,133V, and133W are arranged on the same plane and extend substantially parallel to each other. The left bent portions135U,135V, and135W are arranged on the same plane.

In the present embodiment, the forward inclined portions132U,132V, and132W, the right bent portions134U,134V, and134W, the left straight line portions133U,133V, and133W, and the left bent portions135U,135V, and135W are arranged on the same plane as the lower straight line portions131cU,131cV, and131cW of the right straight line portions131U,131V, and131W, respectively.

The right bent portion134V is formed on a left side of the right bent portion134U, and the right bent portion134W is formed on a left side of the right bent portion134V. Similarly, the left bent portion135V is formed on a left side of the left bent portion135U, and the left bent portion135W is formed on a left side of the left bent portion135V.

In an end surface134Ua of the right bent portion134U of the bus bar10U on a bus bar10V side, a distance D12between the right bent portion134U and the forward inclined portion132V of the bus bar10V is longer than a distance D11between the right bent portion134U and the right straight line portion131V of the bus bar10V.

Regarding the distance D11and the distance D12, a base point of the right bent portion134U on the end surface134Ua of the right bent portion134U on the bus bar10V side is an intersection point XU1between an extension line LU1of an end surface of the right straight line portion131U of the bus bar10U on the bus bar10V side and an extension line LU2of an end surface of the forward inclined portion132U of the bus bar10U on the bus bar10V side, as viewed from above. The same applies to a case in which the end surface134Ua is chamfered as in the present embodiment. That is, the distance D11is a distance between the intersection point XU1and the right straight line portion131V of the bus bar10V, and the distance D12is a distance between the intersection point XU1and the forward inclined portion132V of the bus bar10V.

Accordingly, since it can be ensured that an insulation distance between the right bent portion134U of the bus bar10U and the forward inclined portion132V of the bus bar10V adjacent to the bus bar10U is longer than an insulation distance between the right bent portion134U of the bus bar10U and the right straight line portion131V, the right bent portion134U of the bus bar10U can be prevented from coming into contact with the forward inclined portion132V of the bus bar10V adjacent to the bus bar10U, so that occurrence of a short circuit in the bus bar unit1can be prevented.

In an end surface134Va of the right bent portion134V of the bus bar10V on a bus bar10W side, a distance D22between the right bent portion134V and the forward inclined portion132W of the bus bar10W is longer than a distance D21between the right bent portion134V and the right straight line portion131W of the bus bar10W.

Regarding the distance D21and the distance D22, a base point of the right bent portion134V on the end surface134Va of the right bent portion134U on the bus bar10W side is an intersection point XV1between an extension line LV1of an end surface of the right straight line portion131V of the bus bar10V on the bus bar10W side and an extension line LV2of an end surface of the forward inclined portion132V of the bus bar10V on the bus bar10W side, as viewed from above. The same applies to a case in which the end surface134Va is chamfered as in the present embodiment. That is, the distance D21is a distance between the intersection point XV1and the right straight line portion131W of the bus bar10W, and the distance D22is a distance between the intersection point XV1and the forward inclined portion132W of the bus bar10W.

Accordingly, since it can be ensured that an insulation distance between the right bent portion134V of the bus bar10V and the forward inclined portion132W of the bus bar10W adjacent to the bus bar10V is longer than an insulation distance between the right bent portion134V of the bus bar10V and the right straight line portion131W, the right bent portion134V of the bus bar10V can be prevented from coming into contact with the forward inclined portion132W of the bus bar10W adjacent to the bus bar10V, so that the occurrence of the short circuit in the bus bar unit1can be prevented.

In an end surface135Vb of the left bent portion135V of the bus bar10V on a bus bar10U side, a distance D14between the left bent portion135V and the forward inclined portion132U of the bus bar10U is longer than a distance D13between the left bent portion135V and the left straight line portion133U of the bus bar10U.

Regarding the distance D13and the distance D14, a base point of the left bent portion135V on the end surface135Vb of the left bent portion135V on the bus bar10U side is an intersection point XV2between an extension line LV3of an end surface of the left straight line portion133V of the bus bar10V on the bus bar10U side and an extension line LV4of an end surface of the forward inclined portion132V of the bus bar10V on the bus bar10U side, as viewed from above. The same applies to a case in which the end surface135Vb is chamfered as in the present embodiment. That is, the distance D13is a distance between the intersection point XV2and the left straight line portion133U of the bus bar10U, and the distance D14is a distance between the intersection point XV2and the forward inclined portion132U of the bus bar10U.

Accordingly, since it can be ensured that an insulation distance between the left bent portion135V of the bus bar10V and the forward inclined portion132U of the bus bar10U adjacent to the bus bar10V is longer than an insulation distance between the left bent portion135V of the bus bar10V and the left straight line portion133U, the left bent portion135V of the bus bar10V can be prevented from coming into contact with the forward inclined portion132U of the bus bar10U adjacent to the bus bar10V, so that the occurrence of the short circuit in the bus bar unit1can be prevented.

In an end surface135Wb of the left bent portion135W of the bus bar10W on the bus bar10V side, a distance D24between the left bent portion135W and the forward inclined portion132V of the bus bar10V is longer than a distance D23between the left bent portion135W and the left straight line portion133V of the bus bar10V.

Regarding the distance D23and the distance D24, a base point of the left bent portion135W on the end surface135Wb of the left bent portion135W on the bus bar10V side is an intersection point XW2between an extension line LW3of an end surface of the left straight line portion133W of the bus bar10W on the bus bar10V side and an extension line LW4of an end surface of the forward inclined portion132W of the bus bar10W on the bus bar10V side, as viewed from above. The same applies to a case in which the end surface135Wb is chamfered as in the present embodiment. That is, the distance D23is a distance between the intersection point XW2and the left straight line portion133V of the bus bar10V, and the distance D24is a distance between the intersection point XW2and the forward inclined portion132V of the bus bar10V.

Accordingly, since it can be ensured that an insulation distance between the left bent portion135W of the bus bar10W and the forward inclined portion132V of the bus bar10V adjacent to the bus bar10W is longer than an insulation distance between the left bent portion135W of the bus bar10W and the left straight line portion133V, the left bent portion135W of the bus bar10W can be prevented from coming into contact with the forward inclined portion132V of the bus bar10V adjacent to the bus bar10W, so that the occurrence of the short circuit in the bus bar unit1can be prevented.

Although the embodiment of the present invention have been described above, the present invention is not limited to the above-described embodiments, and modifications, improvements, or the like can be made as appropriate.

At least the following matters are described in the present specification. Components corresponding to the above-described embodiments are shown in parentheses, but the present invention is not limited thereto.

(1) A bus bar unit (bus bar unit1) including:

a first bus bar (bus bar10U) and a second bus bar (bus bar10V) that have a flat plate shape,

wherein the first bus bar and the second bus bar are arranged side by side in a second direction (front-rear direction) orthogonal to a first direction (upper-lower direction) viewed from the first direction,

wherein the first bus bar includes, as viewed from the first direction,a first straight line portion (right straight line portion131U) extending linearly in a third direction (left-right direction) orthogonal to the second direction,a first inclined portion (forward inclined portion132U) extending linearly on a side (front side) opposite to a side (rear side) where the second bus bar is arranged in the second direction with respect to the first straight line portion, as a distance from the first straight line portion increases in the third direction, anda first bent portion (right bent portion134U) connecting the first straight line portion and the first inclined portion,

wherein the second bus bar includes, as viewed from the first direction,a second straight line portion (right straight line portion131V) arranged on the same plane as the first straight line portion and extending linearly substantially parallel to the first straight line portion,a second inclined portion (forward inclined portion132V) arranged on the same plane as the first inclined portion and extending linearly substantially parallel to the first inclined portion, anda second bent portion (right bent portion134V) arranged on the same plane as the first bent portion and connecting the second straight line portion and the second inclined portion, and

wherein in an end surface (end surface134Ua) of the first bent portion on a second bus bar side, a distance (distance D12) between the first bent portion and the second inclined portion is longer than a distance (distance D11) between the first bent portion and the second straight line portion.

According to (1), since it can be ensured that an insulation distance between the first bent portion of the first bus bar and the second inclined portion of the second bus bar is longer than an insulation distance between the first bent portion of the first bus bar and the second straight line portion of the second bus bar, the first bent portion of the first bus bar can be prevented from coming into contact with the second inclined portion of the second bus bar, so that occurrence of a short circuit in the bus bar unit can be prevented.

(2) The bus bar unit according to (1),

wherein the first bus bar includes a first direction extending portion (first extending portion110U, fourth extending portion140U) extending in the first direction, and a second direction extending portion (second extending portion120U, fifth extending portion150U) extending in the second direction, and

wherein the second bus bar includes a third direction extending portion (first extending portion110V, a fourth extending portion140V) extending in the first direction, and a fourth direction extending portion (second extending portion120V, fifth extending portion150V) extending in the second direction.

According to (2), the first bus bar includes the first direction extending portion extending in the first direction, the second direction extending portion extending in the second direction, and the first straight line portion extending in the third direction. Accordingly, when both end portions of the first bus bar are connected to an electric device or the like, even if there is a manufacturing error in the first bus bar, stress can be distributed in three directions perpendicular to each other by the first direction extending portion, the second direction extending portion, and the first straight line portion.

Similarly, the second bus bar includes the third direction extending portion extending in the first direction, the fourth direction extending portion extending in the second direction, and the second straight line portion extending in the third direction. Accordingly, when both end portions of the second bus bar are connected to the electric device or the like, even if there is a manufacturing error in the second bus bar, stress can be distributed in three directions perpendicular to each other by the third direction extending portion, the fourth direction extending portion, and the second straight line portion.

(3) The bus bar unit according to (1) further including:

a third bus bar (bus bar10W) having a flat plate shape,

wherein the third bus bar includes, as viewed from the first direction,a third straight line portion (right straight line portion131W) arranged on the same plane as the first straight line portion and the second straight line portion and extending linearly substantially parallel to the second straight line portion,a third inclined portion (forward inclined portion132W) arranged on the same plane as the first straight line portion and the second straight line portion, and extending linearly substantially parallel to the second inclined portion, anda third bent portion (right bent portion134W) arranged on the same plane as the first bent portion and the second bent portion, and connecting the third straight line portion and the third inclined portion, and

wherein in an end surface (end surface134Va) of the second bent portion on a third bus bar side, a distance (distance D22) between the second bent portion and the third inclined portion is longer than a distance (distance D21) between the first bent portion and the second straight line portion.

According to (3), the bus bar unit further includes the third bus bar, and it can be ensured that an insulation distance between the second bent portion of the second bus bar and the third inclined portion of the third bus bar is longer than an insulation distance between the second bent portion of the second bus bar and the third straight line portion of the third bus bar, so that the second bent portion of the second bus bar can be prevented from coming into contact with the third inclined portion of the third bus bar, and the occurrence of the short circuit in the bus bar unit can be prevented.

(4) The bus bar unit according to (3),

wherein the first bus bar includes a first direction extending portion (first extending portion110U, fourth extending portion140U) extending in the first direction, and a second direction extending portion (second extending portion120U, fifth extending portion150U) extending in the second direction,

wherein the second bus bar includes a third direction extending portion (first extending portion110V, fourth extending portion140V) extending in the first direction, and a fourth direction extending portion (second extending portion120V, fifth extending portion150V) extending in the second direction, and

wherein the third bus bar includes a fifth direction extending portion (first extending portion110W, fourth extending portion140W) extending in the first direction, and a sixth direction extending portion (second extending portion120W, fifth extending portion150W) extending in the second direction.

According to (4), the first bus bar includes the first direction extending portion extending in the first direction, the second direction extending portion extending in the second direction, and the first straight line portion extending in the third direction. Accordingly, when both end portions of the first bus bar are connected to an electric device or the like, even if there is a manufacturing error in the first bus bar, stress can be distributed in three directions perpendicular to each other by the first direction extending portion, the second direction extending portion, and the first straight line portion.

Similarly, the second bus bar includes the third direction extending portion extending in the first direction, the fourth direction extending portion extending in the second direction, and the second straight line portion extending in the third direction. Accordingly, when both end portions of the second bus bar are connected to the electric device or the like, even if there is a manufacturing error in the second bus bar, stress can be distributed in three directions perpendicular to each other by the third direction extending portion, the fourth direction extending portion, and the second straight line portion.

Further, the third bus bar includes the fifth direction extending portion extending in the first direction, the sixth direction extending portion extending in the second direction, and the third straight line portion extending in the third direction. Accordingly, when both end portions of the third bus bar are connected to the electric device or the like, even if there is a manufacturing error in the third bus bar, stress can be distributed in three directions perpendicular to each other by the fifth direction extending portion, the sixth direction extending portion, and the third straight line portion.