CN209912637U

CN209912637U - Shunt resistor assembly

Info

Publication number: CN209912637U
Application number: CN201920799148.4U
Authority: CN
Inventors: 安吉利托·豪托尔; 纳塔涅尔·内里
Original assignee: Yada Electronics International Co Ltd
Current assignee: Yada Electronics International Co Ltd; Astec International Ltd
Priority date: 2019-05-29
Filing date: 2019-05-29
Publication date: 2020-01-07
Anticipated expiration: 2029-05-29

Abstract

The utility model relates to a shunt resistor subassembly. Specifically, the shunt resistor assembly includes: one or more shunt resistors which are configured in a substantially plate-like manner and which are provided with a connection terminal on one side; and the shunt resistor seat is made of an insulating material. The shunt resistor seat is provided with a positioning through hole corresponding to the wiring terminal, and the wiring terminal is inserted into the positioning through hole from one side of the shunt resistor seat so that the shunt resistor is positioned. According to the utility model discloses, through introducing the shunt resistor seat that is provided with positioning hole for adopt the connection of printed wiring board form between the essential element (especially, the grafting of shunt resistor's binding post and the positioning hole of shunt resistor seat), can make the manufacturing of shunt resistor subassembly simpler and cost lower from this, and easily adjust the resistance through deleting or increasing shunt resistor.

Description

Shunt resistor assembly

Technical Field

The present invention relates to a shunt resistor assembly formed in a printed wiring board, and more particularly to a low-cost shunt resistor assembly having a high resistance precision for use with high current, which is formed in a printed wiring board.

Background

Shunt resistors are commonly used in circuits that require excessive current to be shunted, such as ammeters or voltmeters, or as sampling resistors where information about the circuit, such as voltage or current, is to be measured. Taking the measurement of the circuit current as an example, a shunt resistor with a small resistance value should be selected and connected in series in the circuit to measure the voltage signal, for example. The sampling resistor is a precision resistor made of a manganin material, the resistance value is low, the precision is high, the resistance value precision is generally within +/-1%, and a resistor with the precision of +/-0.01% is adopted when higher requirements are met. As the resistance accuracy of the shunt resistor increases, the cost of the corresponding shunt resistor increases greatly.

A shunt resistor for high current, high accuracy is made by welding one or more sheets of manganin alloy to a thick brass lug as shown in fig. 1. The required resistance value can be achieved by cutting the manganese-copper alloy plate. Such high precision shunt resistors need to be customized and manufactured through special machining processes, such as brazing to weld one or more sheets of manganin alloy to a thick brass lug, which requires an operator to manually complete the welding operation and thereby increases production time and manufacturing costs. In addition, since the connection terminals of the shunt resistor are blocked, if it is desired to add a new manganin alloy plate to the welded shunt resistor to change the resistance value, it is necessary to modify the configuration of the entire shunt resistor or use a new tool for this purpose, and thus the implementation of this object becomes troublesome.

It should be noted here that the technical content provided in this section is intended to assist the understanding of the present invention by those skilled in the art, and does not necessarily constitute prior art.

SUMMERY OF THE UTILITY MODEL

The general outline of the present invention is provided in this section, not a full scope of the present invention or a full disclosure of all the features of the present invention.

It is an object of the present invention to provide a shunt resistor assembly made in the form of a printed wiring board, which effectively reduces the production time and the manufacturing cost.

Another object of the present invention is to provide a shunt resistor assembly made in the form of a printed wiring board, which can more conveniently cope with the need of modifying the resistance value by adding or deleting shunt resistors.

To achieve one or more of the above objects, according to the present invention, there is provided a shunt resistor assembly including: one or more shunt resistors which are configured in a substantially plate-like manner and which are provided with a connection terminal on one side; the shunt resistor seat is made of an insulating material; the shunt resistor seat is provided with a positioning through hole corresponding to the wiring terminal, and the wiring terminal is inserted into the positioning through hole from one side of the shunt resistor seat so that the shunt resistor is positioned.

In a shunt resistor assembly according to the present invention, the shunt resistor assembly further includes a first external terminal and a second external terminal, the first external terminal and the second external terminal are used for being connected to corresponding terminals in a circuit to which the shunt resistor assembly is applied, and each of the shunt resistances is connected to the first external terminal and the second external terminal so that each of the shunt resistances forms a parallel relationship.

In a shunt resistor assembly according to the present invention, the shunt resistor assembly further includes a first measurement terminal and a second measurement terminal, and the connection terminal passes through the positioning through hole from one side of the shunt resistor base to be exposed at the other side of the shunt resistor base, and the connection terminal includes a first terminal, a second terminal, a third terminal and a fourth terminal, the first terminal and the second terminal are electrically connected to the first measurement terminal and the second measurement terminal, respectively, and the third terminal and the fourth terminal are electrically connected to the first external terminal and the second external terminal, respectively.

In the shunt resistor assembly according to the present invention, the first measurement terminal has a substantially plate-like configuration, a first through hole corresponding to the first terminal is provided on the first measurement terminal, and the first terminal is electrically connected to the first measurement terminal at the first through hole; the second measurement terminal has a substantially plate-like configuration, on which a second through-hole corresponding to the second terminal is provided, the second terminal being electrically connected to the second measurement terminal at the second through-hole; the first external terminal has a substantially plate-shaped extension portion on which a third through-hole corresponding to the third terminal is provided, the third terminal being electrically connected to the first external terminal at the third through-hole; and/or the second external terminal has a substantially plate-shaped extension portion on which a fourth through-hole corresponding to the fourth terminal is provided, the fourth terminal being electrically connected to the second external terminal at the fourth through-hole.

In a shunt resistor assembly according to the present invention, the first terminal and the first measuring terminal, the second terminal and the second measuring terminal, the third terminal and the first external terminal and/or the fourth terminal and the second external terminal are electrically connected by an induction brazing connection.

In the shunt resistor assembly according to the present invention, the first terminal and the second terminal are close to the symmetry axis of the shunt resistor symmetrically, and the third terminal and the fourth terminal are located away from the symmetry axis symmetrically with respect to the first terminal and the second terminal.

In a shunt resistor assembly according to the present invention, the shunt resistor holder is provided with a spacer, the spacer is in the other side of the shunt resistor holder is extendedly provided, the length of extension of the spacer is greater than or equal to the length of extension of the terminal exposed at the other side of the shunt resistor holder, and the spacer is configured to isolate the first terminal and the second terminal with respect to the third terminal and the fourth terminal, respectively.

According to the utility model discloses an in the shunt resistor subassembly, shunt resistor is provided with and is located first terminal with be used for adjusting between the second terminal the portion of tailorring of shunt resistor's resistance.

In a shunt resistor assembly according to the invention, the shunt resistors are arranged at a distance from each other.

In a shunt resistor assembly according to the present invention, the shunt resistor assembly further comprises a heat sink having a grid-type configuration and including a first portion inserted into a space between the shunt resistors and a second portion extending away from the shunt resistors.

In the shunt resistor assembly according to the present invention, the shunt resistors are arranged to be offset from each other in the longitudinal direction.

In the shunt resistor assembly according to the present invention, the shunt resistors are arranged adjacent to each other in the thickness direction.

In a shunt resistor assembly according to the present invention, the shunt resistance is a shunt resistance made of a manganin alloy.

According to the utility model discloses, introduce the shunt resistor seat that is provided with positioning hole in the shunt resistor subassembly, can make shunt resistor peg graft to positioning hole from this in to can conveniently and fix a position shunt resistor reliably. In other words, according to the present invention, the shunt resistor assembly is manufactured in the form of a printed wiring board, so that the shunt resistor assembly can be manufactured more simply and reliably.

Additionally, according to the present invention, induction welding (e.g., induction brazing) may be employed to automate the welding between the associated components, whereas current shunt resistors require an operator to manually braze, in contrast to the present embodiments of the present invention which greatly reduce production time and labor costs.

In addition, according to the present invention, disposing shunt resistors adjacent to each other makes the shunt resistor assembly smaller in size (shunt resistor thickness, in particular) than existing shunt resistors, well suited for high density power supply applications.

In addition, according to the present invention, since the welding point of the shunt resistor is exposed and the connection between the main members is made in the form of a printed wiring board (in particular, the insertion of the terminal of the shunt resistor into the positioning through hole of the shunt resistor holder), the number of the shunt resistors can be increased and decreased conveniently without changing the structure of the shunt resistor assembly or using a special tool for achieving the purpose.

In addition, according to the utility model discloses, can very conveniently tailor shunt resistor by oneself manually to obtain required resistance value.

Drawings

The features and advantages of one or more embodiments of the present invention will become more readily understood from the following detailed description when taken in conjunction with the accompanying drawings, in which:

fig. 1 schematically shows a perspective view of a prior shunt resistor for large current, high accuracy;

fig. 2 schematically illustrates an exploded view of a shunt resistor assembly made in the form of a printed wiring board according to an exemplary embodiment of the present invention;

fig. 3 schematically shows a front view of a shunt resistor according to an exemplary embodiment of the present invention;

fig. 4 schematically illustrates a perspective view of a shunt resistor assembly after assembly according to an exemplary embodiment of the present invention;

fig. 5 schematically illustrates a perspective view from another angle with respect to the shunt resistor assembly of fig. 4;

figure 6 schematically illustrates a perspective view of a shunt resistor assembly including a heat sink according to a variation of an exemplary embodiment of the present invention;

fig. 7 schematically shows a simplified circuit diagram of an application of a shunt resistor assembly according to an exemplary embodiment of the present invention; and

fig. 8a to 8e schematically show step-by-step assembly views of a shunt resistor assembly according to another exemplary embodiment of the present invention.

Detailed Description

The invention is described in detail below with the aid of exemplary embodiments with reference to the figures. The following detailed description of the invention is merely for purposes of illustration and is in no way intended to limit the invention, its application, or uses.

Referring to fig. 1, a shunt resistor 1 ' for large current, high accuracy is fabricated by welding one or more manganin alloy plates 10 ' to a thick brass tab 20 '. The desired resistance value can be achieved by cutting the manganin alloy sheet 10 ', which leaves the cut portion 17 ' on the manganin alloy sheet 10 '. Two measuring terminals 30 'for measuring voltage drop are provided on the brass wire connecting piece 20'.

Referring to fig. 2, a shunt resistor assembly 1 made in the form of a printed wiring board according to an exemplary embodiment of the present invention may include: a shunt resistor 10; a first external terminal 21 and a second external terminal 22 for connection to a circuit in series; a first measurement terminal 31 and a second measurement terminal 32 for measuring a voltage drop; and a shunt resistance mount 40 made of an insulating material. Here, it should be noted that, in this document, the shunt resistor assembly 10 made in the form of a printed wiring board means: in this shunt resistor assembly 10, the shunt resistors are arranged on the insulated shunt resistor holder 40 like a printed wiring board. The benefits of this arrangement will be described in detail below.

Referring to fig. 2 and 3, the shunt resistor 10 has a substantially plate shape, and a connection terminal including a first terminal 11, a second terminal 12, a third terminal 13, and a fourth terminal 14 is provided on one side (for example, one side in the width direction) thereof. The first terminal 11 and the second terminal 12 are symmetrically disposed near the symmetry axis X of the shunt resistor 10, and the third terminal and the fourth terminal are symmetrically disposed away from the symmetry axis X with respect to the first terminal and the second terminal. Preferably, the shunt resistor 10 is made of manganese copper alloy (mangannin).

Further, referring to fig. 2, the first and

second measurement terminals

31 and 32 are provided with first and second through holes, respectively, and the first and

second terminals

11 and 12 correspond to the first and second through holes of the first and

second measurement terminals

31 and 32, respectively, and are electrically connected, preferably by induction welding (e.g., induction soldering electrical connection). Preferably, the first measurement terminal 31 and the second measurement terminal 32 are made of a conductive material having solderability, such as copper (particularly, brass), aluminum, or tin-plated steel.

Further, the first and second

external terminals

21 and 22 have substantially plate-shaped extending

portions

21a and 22a, the extending

portions

21a and 22a are provided with third and fourth through holes, respectively, and the third and

fourth terminals

13 and 14 correspond to the third and fourth through holes of the first and second

external terminals

21 and 22, respectively, and are electrically connected, preferably by induction welding. The first and second

external terminals

21 and 22 are typically made of brass.

The shunt resistor holder 40 is provided with a plurality of positioning through holes (not shown) corresponding to the connection terminals of the shunt resistor 10, so that the shunt resistor 10 can be mounted on the shunt resistor holder 40 from one side of the shunt resistor holder 40, and the connection terminals of the shunt resistor 10 pass through the positioning through holes and are exposed from the other side of the shunt resistor holder 40, so as to be electrically connected with the corresponding first measurement terminal 31, second measurement terminal 32, first external connection terminal 21 and second external connection terminal 22 at the other side of the shunt resistor holder 40. Preferably, the shunt resistance holder 40 is made of plastic, a base material of a laminated printed wiring board, or a fiber material.

In some examples, an insulating isolation plate may be further disposed on the shunt resistor seat 40, the isolation plate extends from another side of the shunt resistor seat 40, that is, a side opposite to the shunt resistor 10, and the length of the isolation plate is greater than or equal to the length of the terminal exposed after passing through the shunt resistor seat 40. When the shunt resistor 10 is mounted on the shunt resistor holder 40, the first terminal 11 and the second terminal 12 are spaced apart from the third terminal 13 and the fourth terminal 14 by the isolation plate, respectively, so that in an automated induction welding process, terminals of different types are prevented from being welded together, so that waste products are generated, and the yield of automated production is improved.

In some examples, the body portion of the shunt resistor 10 may be covered with an oxidation preventing layer at a portion other than the connection terminal to prevent the shunt resistor 10 from being oxidized to change the resistance value, thereby affecting the measurement accuracy. In addition, the edge portion between the first terminal 11 and the second terminal 12 may be cut as a cut portion to accurately adjust the resistance value of the shunt resistor.

Referring to fig. 4, a perspective view of an assembled shunt resistor assembly 1 according to an embodiment of the present invention is shown. The shunt resistors 10 are arranged side by side on the shunt resistor seat 40 and are spaced apart from each other by a certain distance, which is beneficial to heat dissipation.

Referring to fig. 5, a perspective view of the shunt resistor assembly 1 of fig. 4 from another angle is shown. As can be seen from fig. 5, the corresponding terminals of the shunt resistors 10 are arranged substantially in a straight line, and the contacts (terminals) of the shunt resistor assembly 1 arranged in this way are clear and easy to weld, and especially, automatic induction welding can be adopted, thereby greatly reducing the production time and labor cost. In addition, since the solder joints are exposed, it is possible to easily perform the operation when it is necessary to increase (when the shunt resistor holder 40 is not fully loaded) or decrease the shunt resistor 10 in the shunt resistor assembly 1.

In a high current application, the current flowing through the shunt resistor 10 is large, and therefore, the power consumed by the shunt resistor 10 is large, and there is a possibility that a heat generation problem is caused, and the accuracy of the shunt resistor 10 may be affected. The heat dissipation effect in the embodiment shown in fig. 4 may be limited, and thus a more efficient heat dissipation method is required.

Referring to fig. 6, according to a variation of the above-described exemplary embodiment of the present invention, a heat sink 50 may be provided between the plurality of shunt resistors 10 spaced apart to better dissipate heat. The heat sink 50 has a grid configuration, which may include a first portion (fin) provided to be inserted into a space between the plurality of shunt resistors 10 and a second portion (fin) that may extend away from the shunt resistors 10 to radiate heat outward.

Referring to fig. 7, a practical application of the shunt resistor assembly 1 of the present invention is shown. The shunt resistor assembly 1 is connected as a sampling resistor in series in the circuit of fig. 7 via the first and second

external terminals

21, 22 in order to measure a large total output direct current in the circuit. The total output direct current is equal to the load current Iload through the load L. The total output dc current flows through the shunt resistor assembly 1 and forms a voltage drop across the shunt resistor assembly 1. By measuring the voltage drop between the first measurement terminal and the second measurement terminal of the shunt resistor assembly 1, the total output direct current flowing through, i.e. the load current Iload, can be deduced. Therefore, whether the load L is overloaded or not can be known through the shunt resistor assembly 1, and accordingly, the load L can be controlled and adjusted through, for example, a control feedback circuit, so that the load L always operates in an ideal circuit environment.

In order to reduce the volume of the shunt resistor assembly 1, the distance between the shunt resistors needs to be reduced as much as possible, but too small a distance may cause a heat dissipation problem, and in order to solve this problem, another embodiment of the present invention is provided in fig. 8a to 8 e.

Referring to fig. 8a to 8e, the shunt resistors 10 are closely stacked in a staggered manner, and adjacent shunt resistors 10 may have a small separation distance therebetween. In particular, the shunt resistors 10 are arranged offset from each other in the longitudinal direction, which in the example shown in fig. 8c here corresponds to the length direction of the shunt resistors 10 being substantially rectangular and to the direction of current flow. Preferably, the shunt resistors 10 are arranged adjacent to (in contact with) each other. In the example shown in fig. 8c, the shunt resistors 10 are arranged adjacent to each other in the thickness direction. Stacking the shunt resistor assembly 1A of the shunt resistors 10 in this manner makes it possible to arrange more shunt resistors 10 in a smaller space and secure a certain heat dissipation area, i.e., a heat dissipation surface formed by the shunt resistors 10 being offset from each other.

The positioning through holes on the shunt resistor holder 40 are arranged according to the positions of the first terminal 11, the second terminal 12, the third terminal 13 and the fourth terminal 14 of the shunt resistor 10.

The

terminals

11, 12, 13, 14 of the shunt resistor 10 arranged offset from each other occupy a relatively large longitudinal position, which leads to a relatively tight arrangement of the through-holes in the first measuring terminal 31, the second measuring terminal 32, the first external terminal 21 and the second external terminal 22 to which they are connected. Therefore, in this embodiment, parts of the first through hole on the first measurement terminal 31, the second through hole on the second measurement terminal 32, the third through hole on the first external terminal 21, and the fourth through hole on the second external terminal 22 are present in the form of cutouts. Here, it should be noted that the term "through hole" used in the present invention also includes such a form of notch.

Further, based on the presence of such through-holes in the form of cutouts, solder may easily overflow through the unclosed cutouts during soldering and form connections with solder overflowing from the cutouts of the adjacent other types of terminals, thereby increasing an undesirable defective rate. In this case, therefore, the provision of the isolation plate on the shunt resistance holder 40 is necessary to reduce the defective rate caused during the welding process.

The present invention allows for a variety of possible variations. For example, although it is specifically described above that the shunt resistor assembly may include a shunt resistor, an external connection terminal, a measurement terminal, and a shunt resistor holder, it is contemplated that some components may be omitted in particular cases. For example, in the case where a part (e.g., one connection terminal) of one of the shunt resistances is directly connected to a corresponding terminal in a circuit to which the shunt resistor assembly is applied, the setting of the separate external terminal may be omitted, and in the case where a part (e.g., one connection terminal) of one of the shunt resistances is directly connected to a corresponding terminal in the measurement circuit, the setting of the separate measurement terminal may be omitted.

In this specification, whenever reference is made to "an exemplary embodiment", "some examples", and "illustrated examples", etc., it is intended that a particular feature, structure, or characteristic described in connection with the embodiment/example is included in at least one embodiment/example of the present invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment/example. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment/example, it is submitted that it is within the purview of one skilled in the art to effect such feature, structure, or characteristic in other ones of all the described embodiments/examples.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the specific embodiments/examples described and illustrated in detail herein, and that various changes may be made to the exemplary embodiments by those skilled in the art without departing from the scope defined by the appended claims.

Claims

1. A shunt resistor assembly (1, 1A), the shunt resistor assembly (1, 1A) comprising:

one or more shunt resistors (10), wherein the shunt resistors (10) are substantially plate-shaped, and the shunt resistors (10) are provided with connection terminals on one side; and

the shunt resistor seat (40), the shunt resistor seat (40) is made of insulating materials;

the shunt resistor is characterized in that a positioning through hole corresponding to the wiring terminal is formed in the shunt resistor seat (40), and the wiring terminal is inserted into the positioning through hole from one side of the shunt resistor seat (40) so that the shunt resistor (10) is positioned.

2. A shunt resistor assembly (1, 1A) according to claim 1, characterized in that the shunt resistor assembly (1, 1A) further comprises a first external terminal (21) and a second external terminal (22), the first external terminal (21) and the second external terminal (22) being for connection with corresponding terminals in an electrical circuit to which the shunt resistor assembly (1, 1A) is applied, and each shunt resistor (10) is connected to the first external terminal (21) and the second external terminal (22) such that each shunt resistor (10) forms a parallel relationship.

3. A shunt resistor assembly (1, 1A) according to claim 2, wherein:

the shunt resistor assembly (1, 1A) further comprises a first measurement terminal (31) and a second measurement terminal (32), and

the connection terminal passes through the positioning through hole from one side of the shunt resistor holder (40) and is exposed at the other side of the shunt resistor holder (40), and comprises a first terminal (11), a second terminal (12), a third terminal (13) and a fourth terminal (14), wherein the first terminal (11) and the second terminal (12) are electrically connected to the first measuring terminal (31) and the second measuring terminal (32) respectively, and the third terminal (13) and the fourth terminal (14) are electrically connected to the first external terminal (21) and the second external terminal (22) respectively.

4. A shunt resistor assembly (1, 1A) according to claim 3, wherein:

the first measurement terminal (31) has a substantially plate-like configuration, a first through hole corresponding to the first terminal (11) is provided on the first measurement terminal (31), and the first terminal (11) is electrically connected to the first measurement terminal (31) at the first through hole;

the second measurement terminal (32) has a substantially plate-like configuration, a second through hole corresponding to the second terminal (12) is provided on the second measurement terminal (32), and the second terminal (12) is electrically connected to the second measurement terminal (32) at the second through hole;

the first external connection terminal (21) has a substantially plate-shaped extension portion (21a), a third through hole corresponding to the third terminal (13) is provided on the extension portion (21a) of the first external connection terminal (21), and the third terminal (13) is electrically connected to the first external connection terminal (21) at the third through hole; and/or

The second external terminal (22) has a substantially plate-shaped extended portion (22a), a fourth through hole corresponding to the fourth terminal (14) is provided on the extended portion (22a) of the second external terminal (22), and the fourth terminal (14) is electrically connected to the second external terminal (22) at the fourth through hole.

5. A shunt resistor assembly (1, 1A) according to claim 3, characterized in that the electrical connection of the first terminal (11) and the first measurement terminal (31), the second terminal (12) and the second measurement terminal (32), the third terminal (13) and the first external terminal (21) and/or the fourth terminal (14) and the second external terminal (22) is an electrical connection achieved by an inductive soldering connection.

6. A shunt resistor assembly (1, 1A) according to claim 3, characterized in that the first terminal (11) and the second terminal (12) are symmetrically arranged close to an axis of symmetry (X) of the shunt resistance (10), and the third terminal (13) and the fourth terminal (14) are symmetrically arranged further away from the axis of symmetry (X) than the first terminal (11) and the second terminal (12).

7. A shunt resistor assembly (1, 1A) according to claim 3, characterized in that the shunt resistor holder (40) is provided with a separation plate extendedly provided at the other side of the shunt resistor holder (40), the separation plate extending for a length greater than or equal to a length of the connection terminal exposed at the other side of the shunt resistor holder (40), and the separation plate is configured to separate the first terminal (11) and the second terminal (12) with respect to the third terminal (13) and the fourth terminal (14), respectively.

8. A shunt resistor assembly (1, 1A) according to claim 3, characterized in that the shunt resistor (10) is provided with a cut between the first terminal (11) and the second terminal (12) for adjusting the resistance value of the shunt resistor (10).

9. A shunt resistor assembly (1) according to any of claims 1 to 8, characterized in that the shunt resistors (10) are arranged at a distance from each other.

10. A shunt resistor assembly (1) according to claim 9, characterized in that the shunt resistor assembly (1) further comprises a heat sink (50), the heat sink (50) having a grid-type configuration and comprising a first portion and a second portion, the first portion being inserted in the space between the shunt resistors (10) and the second portion extending away from the shunt resistors (10).

11. A shunt resistor assembly (1A) according to any one of claims 1 to 8, characterized in that the shunt resistors (10) are arranged offset from each other in the longitudinal direction.

12. A shunt resistor assembly (1A) according to claim 11, characterized in that the shunt resistances (10) are arranged adjacent to each other in the thickness direction.

13. A shunt resistor assembly (1) according to any one of claims 1 to 8, characterized in that said shunt resistance (10) is a shunt resistance made of a manganin alloy.