阅读说明：本技术 连接单元 (Connection unit ) 是由 森真吾 岩坂博之 箕轮亮太 于 2018-08-09 设计创作，主要内容包括：连接单元具备电磁继电器和与该电磁继电器连接的母线,在该连接单元中,与第一固定触点端子连接的第一母线相对于可动接触片的与一方的面位于触点接触分离方向的相反侧的另一方的面在触点接触分离方向上与所述可动接触片分开地对置配置,与触点接触分离方向交叉并且沿着可动接触片的第一可动触点和第二可动触点的排列配置方向延伸,在从触点接触分离方向观察时的平面图中,第一母线的至少一部分与可动接触片重叠。(The connection unit includes an electromagnetic relay and a bus bar connected to the electromagnetic relay, and in the connection unit, a first bus bar connected to the first fixed contact terminal is disposed to face the movable contact piece in the contact/separation direction with respect to the other surface of the movable contact piece, which is located on the opposite side of the contact/separation direction from the one surface, intersects the contact/separation direction, extends along the arrangement direction of the first movable contact and the second movable contact of the movable contact piece, and at least a part of the first bus bar overlaps the movable contact piece in a plan view when viewed from the contact/separation direction.)

1. A connection unit having an electromagnetic relay and a bus bar connected to the electromagnetic relay, characterized in that,

the electromagnetic relay includes:

a housing;

a first fixed contact terminal fixed to the housing, extending outward from an inside of the housing, and having a first fixed contact;

a second fixed contact terminal fixed to the housing, extending outward from an inside of the housing, and having a second fixed contact;

a movable contact piece having a first movable contact point and a second movable contact point on one surface, the first movable contact point and the second movable contact point being capable of being brought into contact with and separated from a first fixed contact point of the first fixed contact point terminal and a second fixed contact point of the second fixed contact point terminal, respectively, in a contact point contact and separation direction, and being disposed in the housing so as to be movable in the contact point contact and separation direction;

the bus bar includes a first bus bar connected to the first fixed contact terminal outside the housing and a second bus bar connected to the second fixed contact terminal,

the first bus bar is disposed facing the movable contact piece in the contact/separation direction with respect to the other surface of the movable contact piece, the other surface being located on the opposite side of the contact/separation direction from the one surface, and extends along the arrangement direction of the first and second movable contacts of the movable contact piece, the first bus bar intersecting the contact/separation direction,

at least a part of the first bus bar overlaps with the movable contact piece in a plan view when viewed from the contact separation direction.

2. The connection unit of claim 1,

in the plan view, the first bus bar extends to face a central portion of the movable contact piece in an arrangement direction of the first movable contact and the second movable contact.

3. The connection unit of claim 2,

in the plan view, the first bus bar overlaps the entire movable contact piece in the arrangement direction of the first movable contact and the second movable contact.

4. The connection unit according to any one of claims 1 to 3,

a connection end surface of the first fixed contact terminal connected to the first bus bar and a connection end surface of the second fixed contact terminal connected to the second bus bar are positioned to protrude outward from an outer side surface of the case,

the heights of the connection end surface of the first fixed contact terminal with respect to the first outer side surface of the housing and the connection end surface of the second fixed contact terminal are different from each other.

5. The connection unit according to any one of claims 1 to 3,

a connection end surface of the first fixed contact terminal protrudes from a first outer side surface of the housing and is connected to the first bus bar,

a connection end surface of the second fixed contact terminal protrudes from a second outer side surface intersecting the first outer side surface of the housing to an outside of the housing and is connected to the second bus bar.

6. The connection unit of claim 5,

the first bus bar is disposed along the first outer side surface of the case.

7. The connection unit according to any one of claims 1 to 3,

the first bus bar is disposed on a first outer side surface of the case,

the first fixed contact terminal and the second fixed contact terminal are disposed on a second outer side surface and a third outer side surface which intersect the first outer side surface of the housing and face each other, respectively, so as to protrude outward from the housing, and are connected to the first bus bar and the second bus bar.

8. The connection unit according to any one of claims 1 to 7,

an insulating member is disposed outside the case between the first bus bar and the second bus bar.

Technical Field

The present disclosure relates in particular to a connection unit comprising an electromagnetic relay and a bus bar.

Background

Conventionally, an electromagnetic relay that opens and closes a current path is connected to a power supply source and other electronic components using a bus bar. For example, there is an electromagnetic relay exemplified in patent document 1. The electromagnetic relay of patent document 1 will be described with reference to fig. 18. Fig. 18 is an explanatory diagram showing a flow of current in a state where the electromagnetic relay of patent document 1 is closed.

In patent document 1, a pair of contact portions 130a of the movable contact 130 is brought into contact with the fixed contacts 118a of the fixed contacts 111 and 112, respectively, to cause a current Ip to flow. In the fixed contacts 111 and 112, the contact conductor portions 115 having the fixed contacts 118a are C-shaped and inverted C-shaped, and therefore, a section in which the directions of the currents Ip flowing through the contact conductor portions 115 and the movable contact 130 are opposite to each other is generated. In this interval, electromagnetic repulsion forces in opposite directions are generated by lorentz forces caused by the current Ip flowing through the contact conductor portion 115 and the movable contact piece 130, and the contact pressure between the pair of contact portions 130a of the movable contact piece 130 and the respective fixed contacts 118a is increased.

Disclosure of Invention

Technical problem to be solved by the invention

However, the current has a property of flowing on the shortest path, and even if the contact conductor portion 115 is C-shaped or inverted C-shaped, the current Ip does not flow through the portion W of the C-shaped or inverted C-shaped upper plate portion 116 on the side of the connecting shaft 131, but flows only through the peripheral portions of both ends of the movable contact 130. As a result, electromagnetic repulsive force due to the lorentz force is generated only at the peripheral portions of both ends of the movable contact 130. Therefore, there is a possibility that the contacts may be separated by another electromagnetic repulsive force generated between the contact portions 130a of the movable contact 130 and the contacts of the fixed contacts 118 a.

In view of the above, an object of the present disclosure is to provide a connection unit that suppresses separation of contacts due to electromagnetic repulsion between the contacts.

Technical solution for solving technical problem

In order to solve the above-described problems, a connection unit according to one aspect of the present disclosure includes an electromagnetic relay and a bus bar connected to the electromagnetic relay,

the electromagnetic relay includes:

a housing;

a first fixed contact terminal fixed to the housing, extending outward from an inside of the housing, and having a first fixed contact;

a second fixed contact terminal fixed to the housing, extending outward from an inside of the housing, and having a second fixed contact;

a movable contact piece having a first movable contact point and a second movable contact point on one surface, the first movable contact point and the second movable contact point being capable of being brought into contact with and separated from a first fixed contact point of the first fixed contact point terminal and a second fixed contact point of the second fixed contact point terminal, respectively, in a contact point contact and separation direction, and being disposed in the housing so as to be movable in the contact point contact and separation direction;

the bus bar includes a first bus bar connected to the first fixed contact terminal outside the housing and a second bus bar connected to the second fixed contact terminal,

the first bus bar is disposed facing the movable contact piece in the contact/separation direction with respect to the other surface of the movable contact piece, the other surface being located on the opposite side of the contact/separation direction from the one surface, and extends along the arrangement direction of the first and second movable contacts of the movable contact piece, the first bus bar intersecting the contact/separation direction,

at least a part of the first bus bar overlaps with the movable contact piece in a plan view when viewed from the contact separation direction.

In each region where the first bus bar and the movable contact piece overlap each other in a plan view when viewed from the contact and separation direction, a direction of a current flowing through the first bus bar, which intersects the contact and separation direction and extends along the arrangement direction of the first movable contact and the second movable contact of the movable contact piece, and a direction of a current flowing through the movable contact piece are opposite to each other. Accordingly, since a force for pressing the movable contact toward the fixed contacts is generated by the lorentz force on the movable contact piece, the contact pressure between the movable contact of the movable contact piece and the first and second fixed contacts can be increased. In this way, the movable contact piece can be prevented from being separated from the first and second fixed contact terminals by the electromagnetic repulsive force derived from the lorentz force.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present disclosure, it is possible to provide a connection unit capable of suppressing the contact separation caused by the electromagnetic repulsive force between the contacts.

Drawings

Fig. 1 is a circuit diagram schematically showing an example of an application scenario of the connection unit according to embodiment 1.

Fig. 2 is a circuit diagram schematically showing an example of an application scenario of the connection unit according to embodiment 1.

Fig. 3 is a front view schematically showing a connection unit according to embodiment 1.

Fig. 4 is a front sectional view schematically showing the connection unit in a separated state.

Fig. 5 is a plan view seen from the direction V of fig. 4.

Fig. 6 is a front sectional view schematically showing the connection unit in a closed state.

Fig. 7 is an explanatory diagram showing the direction of current flowing through the connection unit in the closed state.

Fig. 8 is a front cross-sectional view schematically showing the connection unit in the separated state according to embodiment 2.

Fig. 9 is a front sectional view schematically showing the connection unit in a closed state.

Fig. 10 is a front cross-sectional view schematically showing the connection unit in the separated state according to embodiment 3.

Fig. 11 is a partially enlarged view of fig. 10.

Fig. 12 is a front sectional view schematically showing the connection unit in a closed state.

Fig. 13 is a front cross-sectional view schematically showing the connection unit in a separated state according to a modification of embodiment 3.

Fig. 14 is a front cross-sectional view schematically showing the connection unit in the separated state according to embodiment 4.

Fig. 15 is a front cross-sectional view schematically showing the connection unit in the separated state according to embodiment 5.

Fig. 16 is a front cross-sectional view schematically showing the connection unit in the separated state according to embodiment 6.

Fig. 17 is a front cross-sectional view schematically showing a connection unit in a separated state in a modification.

Fig. 18 is a front partial sectional view of a conventional connection unit.

Detailed Description

Hereinafter, an embodiment of the present disclosure will be described with reference to the accompanying drawings. In the following description, terms indicating specific directions or positions (for example, terms including "up", "down", "left" and "right") are used as necessary to facilitate understanding of the disclosure with reference to the drawings, and the technical scope of the present disclosure is not limited by the meanings of the terms. The following description is merely exemplary in nature and is not intended to limit the present disclosure in any way, application, or uses. The drawings are only schematic, and the proportions of the dimensions and the like do not necessarily coincide with reality.

(application example)

First, an example of a scenario to which the present disclosure is applied will be described with reference to fig. 1 and 2. Fig. 1 and 2 are circuit diagrams schematically showing an example of an application scenario of the connection unit according to the embodiment. As shown in fig. 1, the connection unit 1 of the present embodiment is connected between a battery 3 and an electric motor 5 of an electric vehicle, for example.

The battery 3 and the motor 5 are connected via a connection unit 1 and an inverter 7. The inverter 7 is connected to a motor 5 and a generator 8. The connection unit 1 opens and closes a current path for supplying power from the battery 3 to the motor 5 via the inverter 7. The connection unit 1 opens and closes a current path for charging the battery 3 from the generator 8 via the inverter 7. A capacitor 9 is provided in parallel with the inverter 7.

Between battery 3 and inverter 7, a precharge relay 10 and a resistor 11 are connected in parallel with connection means 1. The relay 10 and the resistor 11 are provided to prevent an excessive inrush current from flowing into the connection unit 1 when a closed circuit is formed.

The connection unit 1 includes an electromagnetic relay 13 and a bus bar 15 connected to the electromagnetic relay 13. As shown in fig. 2, bus 15 includes first bus 15a connected to node a on the battery 3 side and second bus 15B connected to node B on the inverter 7 side. First bus 15a may be connected to node B, and second bus 15B may be connected to node a. The structure of the connection unit 1 will be described below.

(embodiment mode 1)

A connection unit 1 according to embodiment 1 of the present disclosure will be described with reference to fig. 3 and 4. Fig. 3 is a front view schematically showing the connection unit 1 of embodiment 1. Fig. 4 is a front cross-sectional view schematically showing the connection unit 1 in a separated state.

As shown in fig. 3 and 4, the electromagnetic relay 13 includes a first fixed contact terminal 17 and a second fixed contact terminal 20 connected to the bus bar 15, a movable contact piece 35, and a case 24 that houses the first fixed contact terminal 17 and the second fixed contact terminal 20. The first fixed contact terminal 17 and the second fixed contact terminal 20 are fixed to the housing 24 and are arranged separately from each other. The case 24 is formed in a substantially rectangular box shape by, for example, an insulating resin.

As shown in fig. 3, the bus bar 15 includes a first bus bar 15a connected to the first fixed contact terminal 17 and a second bus bar 15b connected to the second fixed contact terminal 20 outside the case 24. The first bus bar 15a and the second bus bar 15b are formed of, for example, metal plates.

As shown in fig. 4, the first fixed contact terminal 17 and the second fixed contact terminal 20 are arranged in line along the longitudinal direction of the first bus bar 15 a. The movable contact piece 35 is disposed between the first fixed contact terminal 17 and the second fixed contact terminal 20 in the housing 24 so as to be movable in the contact/separation direction. The first fixed contact terminal 17 includes: a substantially cylindrical support conductor portion 18 to which the first bus bar 15a is connected; and a first terminal portion 19 having a first fixed contact 19a that is brought into contact with and separated from the first movable contact 35a of the movable contact piece 35. The second fixed contact terminal 20 includes: a substantially cylindrical support conductor part 21 to which the second bus bar 15b is connected; and a second terminal portion 22 having a second fixed contact 22a that is brought into contact with and separated from the second movable contact 35b of the movable contact piece 35.

The first terminal portion 19 and the second terminal portion 22 are made of metal and have a flat plate shape. The support conductor portion 18 and the first terminal portion 19 are connected to the support conductor portion 21 and the second terminal portion 22, respectively, by brazing, for example. In addition to brazing, fitting or screw fastening may be used. In the following description, the direction in which the first movable contact 35a and the second movable contact 35b of the movable contact piece 35 are separated from the first fixed contact 19a and the second fixed contact 22a is referred to as an upper direction, and the direction in which the first movable contact 35a and the second movable contact 35b are in contact with the first fixed contact 19a and the second fixed contact 22a is referred to as a lower direction. The contact/separation direction is a direction in which the first movable contact 35a and the second movable contact 35b are separated from or brought into contact with the first fixed contact 19a and the second fixed contact 22 a.

The support conductor portions 18,21 are formed with screw holes 18a,21a so as not to pass through from one end to the other end. The first bus bar 15a is fixed to the metal support conductor portion 18 by a screw 25 screwed into the screw hole 18 a. The second bus bar 15b is fixed to the metal support conductor portion 21 by a screw 26 screwed into the screw hole 21 a. The support conductor portions 18,21 extend from the inside of the housing 24 to the outside of the housing 24, and protrude from an opening portion 24b provided on an outer side surface 24a which is an upper surface of the housing 24.

The height Ha from the outer surface 24a of the case 24 to the connection end surface 18b of the support conductor portion 18 and the first bus bar 15a is higher than the height Hb from the outer surface 24a of the case 24 to the connection end surface 21b of the support conductor portion 21 and the second bus bar 15 b. Thus, the height Ha of the connection end surface 18b of the first fixed contact terminal 17 and the height Hb of the connection end surface 21b of the second fixed contact terminal 20 with respect to the outer side surface 24a of the housing 24 are different from each other. Therefore, the first bus bar 15a can be disposed above the second bus bar 15b with an insulation gap maintained between the two bus bars 15a and 15 b. This can prevent the first bus bar 15a and the second bus bar 15b from interfering with each other.

The electromagnetic relay 13 includes a contact mechanism unit 29 and an electromagnet unit 30 in the housing 24.

The contact mechanism unit 29 includes: a movable shaft 31 that can move up and down in the axial direction; a movable iron core 33 connected to a lower portion of the movable shaft 31; a movable contact piece 35 into which the movable shaft 31 is inserted; a contact spring 37 for biasing the movable contact piece 35 downward along the contact/separation direction; a stopper 38 for preventing the movable contact piece 35 from moving downward; and a return spring 39 for biasing the movable core 33 upward in the contact/separation direction.

The movable shaft 31 is inserted into the movable contact piece 35 at the upper portion and is fixed to the movable core 33 at the lower end. The lower portion of the movable shaft 31 is inserted into the electromagnet unit 30 together with the movable core 33, and is supported so as to be capable of reciprocating in the axial direction of the movable shaft 31. The movable shaft 31 has a disc-shaped flange 31a at its upper end. A contact spring 37 is provided between the disk-shaped flange 31a and the movable contact piece 35, and the contact spring 37 biases the movable contact piece 35 in the contact direction along the contact/separation direction.

The movable contact piece 35 is disposed in the housing 24 so as to be movable in the contact/separation direction. The surface (i.e., the lower surface) of the movable contact piece 35 on the electromagnet unit 30 side has a first movable contact 35a and a second movable contact 35b that can be brought into contact with and separated from the first fixed contact 19a and the second fixed contact 22a in the contact-and-separation direction in the axial direction of the movable shaft 31. The first movable contact 35a is opposed to the first fixed contact 19a of the first fixed contact terminal 17 so as to be able to be separated from and in contact with each other. The second movable contact 35b is opposed to the second fixed contact 22a of the second fixed contact terminal 20 so as to be able to be separated from and brought into contact with each other. The first bus bar 15a is disposed on the upper surface of the movable contact piece 35 on the opposite side of the lower surface in the contact/separation direction, so as to face the movable contact piece 35 in the contact/separation direction. The outer surface 24a of the housing 24 is positioned between the first bus bar 15a and the movable contact piece 35.

The lower end of the movable core 33 is supported by a return spring 39. The movable core 33 protrudes upward by the biasing force of the return spring 39 in the non-excited state of the electromagnet unit 30, and is pulled downward against the biasing force of the return spring 39 in the excited state.

The electromagnet unit 30 includes a coil 41, an insulating drum 43, a first yoke 45, a U-shaped second yoke 47, and a stopper 49. The coil 41 is wound around the trunk 43a of the bobbin 43. The first yoke 45 is fixed between the upper ends of the second yoke 47 which become open ends. The stopper 49 is provided above the first yoke 45 and regulates the upward movement of the movable core 33.

Reference is next made to fig. 5. Fig. 5 is a plan view as viewed from the V direction of fig. 4 (i.e., the upper side in the contact separation direction). In fig. 5, the housing 24 and the contact mechanism unit 29 are not shown in order to facilitate understanding of the positional relationship between the movable contact piece 35 and the first bus bar 15 a.

The first bus bar 15a extends in a plan view when viewed from the contact separation direction, facing the central portion 35c of the movable contact piece 35 in the arrangement direction of the first movable contact 35a and the second movable contact 35 b. The first bus bar 15a overlaps the entire movable contact piece 35 in the arrangement direction of the first movable contact 35a and the second movable contact 35b in a plan view when viewed from the contact/separation direction.

Next, the operation of the electromagnetic relay 1 having the above-described configuration will be described. First, as shown in fig. 3, when no voltage is applied to the coil 41, the movable core 33 is biased upward by the spring force of the return spring 39. Thereby, the movable shaft 31 integrated with the movable core 33 is pressed upward, and the movable contact piece 35 is pressed upward. As a result, the first movable contact 35a and the second movable contact 35b of the movable contact piece 35 are in a separated state from the first fixed contact 19a of the first fixed contact terminal 19 and the second fixed contact 22a of the second fixed contact terminal 22.

Then, voltage is applied to the coil 41 to be excited, and the movable core 33 slides downward against the spring force of the return spring 39 as shown in fig. 6. Thereby, the first and second movable contacts 35a and 35b are brought into a closed state in contact with the first and second fixed contacts 19a and 22 a. In this closed state, as shown in fig. 7, a current Ic flows from the first bus bar 15a connected to the battery 3 to the second bus bar 15b through the first fixed contact terminal 17, the movable contact piece 35, the second fixed contact terminal 20, and the second bus bar 15 b.

The first bus bar 15a is disposed to face the movable contact piece 35 in the contact/separation direction, with respect to a surface (lower surface) of the movable contact piece 35 having the first movable contact 35a and the second movable contact 35b and the other surface (upper surface) located on the opposite side to the contact/separation direction. The first bus bar 15a intersects with the contact/separation direction and extends in a direction of coupling the first movable contact 35a and the second movable contact 35b of the movable contact piece 35. Therefore, for example, when the current Ic flows from the first bus bar 15a to the second bus bar 15b, in each region where the first bus bar 15a overlaps the movable contact piece 35 in a plan view when viewed from the contact separation direction, a section D appears in which the direction of the current Ic flowing through the first bus bar 15a extending above the movable contact piece 35 is opposite to the direction of the current Ic flowing through the movable contact piece 35. In this section D, due to the lorentz force, an electromagnetic repulsive force F is generated in which the first bus bar 15a and the movable contact piece 35 repel each other in the contact and separation direction. As a result, a force is generated in the movable contact piece 35 that presses the first fixed contact 19a and the second fixed contact 22a in the axial direction of the movable shaft 31. In this way, the first movable contact 35a and the second movable contact 35b are pressed against the first fixed contact 19a and the second fixed contact 22a by the electromagnetic repulsive force F, and therefore, the movable contact piece 35 can be prevented from being separated from the first fixed contact terminal 17 and the second fixed contact terminal 20. Further, since it is not necessary to provide the first fixed contact terminal 17 and the second fixed contact terminal 20 so that the first fixed contact terminal 17 and the second fixed contact terminal 20 are positioned directly above the movable contact piece 35 in the electromagnetic relay 13 as in the conventional example, the electromagnetic relay 13 does not become large.

In a plan view when viewed from the contact separation direction, at least a part of the first bus bar 15a may overlap the movable contact piece 35, and the electromagnetic repulsive force F may be generated in each overlapping region. The larger the area in which the first bus bar 15a overlaps the movable contact piece 35 in a plan view as viewed from the contact and separation direction, the larger the lorentz force. Since the lorentz force is proportional to the square of the current value, the contact pressure between the first and second movable contacts 35a and 35b and the first and second fixed contacts 19a and 22a increases as the current value flowing through the movable contact piece 35 increases. As a result, the contact separation can be suppressed.

The first bus bar 15a extends so as to face the central portion 35c of the movable contact piece 35 in a direction of connecting the two movable contacts 35a and 35b, i.e., the first movable contact 35a and the second movable contact 35b, when viewed in a contact/separation direction. Thus, when the current Ic flows in the closed state, the central portion 35c of the movable contact piece 35 can be pressed downward, and therefore the first movable contact 35a and the second movable contact 35b at both ends of the movable contact piece 35 can be uniformly brought into contact with both the fixed contacts, i.e., the first fixed contact terminal 17 and the second fixed contact terminal 20.

In a plan view when viewed from the contact separation direction, the first bus bar 15a overlaps the entire movable contact piece 35 in a direction in which the two movable contacts, i.e., the first movable contact 35a and the second movable contact 35b, are coupled. This causes a downward force to be generated on the entire movable contact piece 35, and therefore the movable contact piece 35 can be further prevented from being separated from the first fixed contact 19a and the second fixed contact 22a of the first fixed contact terminal 17 and the second fixed contact terminal 20.

Further, since the connection end surface 18b of the support conductor portion 18 connected to the first bus bar 15a and the connection end surface 21b of the support conductor portion 21 connected to the second bus bar 15b have different heights from the outer surface 24a, the first bus bar 15a extends so as to face the movable contact piece 35, and may extend so as to face the second bus bar 15b, depending on the case. As a result, the degree of freedom in designing the arrangement of the first bus bar 15a and the second bus bar 15b is increased.

(embodiment mode 2)

Next, a connection unit 1a according to embodiment 2 of the present disclosure will be described with reference to fig. 8. Fig. 8 is a front sectional view of a connection unit 1a of embodiment 2. The first fixed contact terminal 17 and the second fixed contact terminal 20 of the electromagnetic relay 13 according to embodiment 1 protrude from the same outer side surface 24a of the case 24, while the second fixed contact terminal 20 of the electromagnetic relay 13a according to embodiment 2 protrudes from an outer side surface 24c of the case 24 different from the outer side surface 24a of the case 24 from which the first fixed contact terminal 17 protrudes. The configuration of the connection unit 1a in embodiment 2 is common to the connection unit 1 in embodiment 1 except for the matters described below.