CN2634608Y

CN2634608Y - Precision shunt resistor

Info

Publication number: CN2634608Y
Application number: CN 03268958
Authority: CN
Inventors: 彭德龙
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-07-09
Filing date: 2003-07-09
Publication date: 2004-08-18
Anticipated expiration: 2013-07-09

Abstract

The utility model provides a precision shunt resistor, which belongs to a foundational electrical component in an electric field. The utility model is composed of a resistor body and a bus manufactured by a red copper sheet, and is characterized in that the resistor body is manufactured by a manganese copper sheet whose temperature coefficient is lower than 20 ppm. A transition manganese copper-red copper alloying belt which is provided with the lower than 50 ppm temperature coefficient and is formed by the electron beam welding is equipped between the resistor body and the bus, and a mounting hole and a voltage output terminal are equipped on the bus. The utility model has the advantages of high reliability, good thermal stability, low temperature coefficient, big accessible rated current, small volume and maximum material saving, etc., and simultaneously, can achieve automation production.

Description

Accurate shunt resistor

Affiliated technical field

The utility model belongs to a kind of basic electric elements in the electricity field, particularly a kind of accurate shunt resistor.

Technical background

Shunt resistor is widely used in also can be used as the critical piece of current sensor in the various instrument and meters that digital watt-hour meter, high-accuracy test instrumentation and all measure, take a sample, shunt electric current.The previous low conventional, electric-resistance device of resistance that adopts is made shunt resistor.Their shortcoming is that thermal stability is very poor, precision is low, when passing through bigger electric current on the shunt resistor, on resistor, produce bigger heat, this heat can not distribute soon, thereby resistance can change a lot, cause poor stability, precision low, the supporting use of instrument, instrument that can not be higher with precision.For addressing these problems, the patent No. is the patent of " high-accuracy shunt resistor " for " 92218841.6 " title, a kind of shunt resistor of being made up of resistance wire, resistance wire lead-in wire, housing, inserts etc. has been proposed, its feature is to adopt the many resistance wires that temperature coefficient is lower, in parallel, be welded on and constitute the shunt resistance body on the bus-bar, put it into again in the housing, in housing, insert the filler of good heat dispersion performance, form the higher relatively shunt resistor of precision.This shunt resistor mainly is at the design of the temperature coefficient of shunt resistor, the resistance wire that constitutes resistive element is realized being connected by silver soldering with bus-bar, though the thermal stability than conventional, electric-resistance improves, but the shunt resistor of this structure exists the shortcoming that rated current is less, thermal stability is still good inadequately, production efficiency is lower that volume is big, can pass through.

Summary of the invention

The purpose of this utility model is to provide a kind of accurate shunt resistor that reliability height, Heat stability is good, temperature coefficient rated current low, that can pass through are big, be convenient to automated production that has.

The purpose of this utility model is realized by following technical scheme: form accurate shunt resistor by the bus-bar that resistive element and employing copper plate are made, characteristics are that resistive element adopts temperature coefficient to be lower than the copper-manganese plate of 20ppm, have the temperature coefficient that forms by the electron beam welding fusion to be lower than transition copper-manganese-red copper alloy band of 50ppm between resistive element and bus-bar.On bus-bar, have installing hole and voltage output end.Accurate shunt resistor provided by the utility model, owing to adopted the copper-manganese plate to do resistive element, make the rated current of passing through increase greatly, because the temperature coefficient of copper-manganese plate is lower than 20ppm, guaranteed that accurate shunt resistor has lower temperature coefficient, simultaneously, the low-temperature coefficient transition copper-manganese-red copper alloy band that between resistive element and bus-bar, forms by the electron beam welding fusion, the reliability that makes bus-bar be connected with resistive element increases greatly, the electric current of importing from the installing hole of bus-bar, can flow through resistive element from bus-bar by the copper-manganese of the transition between resistive element and the bus-bar-red copper alloy band equably, significantly reduced the contact resistance between resistive element and the bus-bar, further improved thermal stability, and dwindled the volume of shunt resistor, owing to directly installing hole is set on bus-bar, make shunt resistor and instrument, connection between the instrument, very simple.Simultaneously,, also saved material widely, can also realize the automated production of shunt resistor owing to adopted this structure.

Accurate shunt resistor provided by the utility model has reliability height, Heat stability is good, temperature coefficient rated current low, that can pass through is big, volume is little, advantage such as economical with materials to greatest extent, simultaneously, this accurate shunt resistor can also be realized automated production, has improved production efficiency greatly.

Description of drawings

Fig. 1 is the structural representation of an embodiment of accurate shunt resistor provided by the utility model:

Fig. 2 is the top view of embodiment one;

Fig. 3 is the partial sectional view of Fig. 2;

Fig. 4 makes the used bimetal band that is formed through electron beam welding by copper belt and copper-manganese band of accurate shunt resistor;

Fig. 5 is the sectional view of bimetal band shown in Figure 4.

1 is the bus-bar of doing with red copper among Fig. 1, Fig. 2, Fig. 3, and 2 are the resistive element with the making of copper-manganese plate, and 3 is between bus-bar and the resistive element, and by the low-temperature coefficient transition manganin district that the electron beam welding fusion forms, 4 is installing hole, and 5 is voltage output end.Among Fig. 4, Fig. 51 for the red copper band of making bus-bar, 2 for making the copper-manganese band of resistive element, 3 low-temperature coefficient transition copper-manganese red copper alloy bands for red copper band and copper-manganese band are formed after the electron beam welding fusion.

Embodiment

Accurate shunt resistor embodiment provided by the utility model is as follows: width and the thickness of at first choosing the copper-manganese band according to resistance, the rated current of shunt resistance, red copper band with copper-manganese band and equal thickness carries out electron beam welding afterwards, form bimetal band as shown in Figure 4, select die stamping to go out as shown in Figure 1 shunt resistor by designing requirement then, can adopt metal cutting to change the thickness of resistive element, thereby adjust resistance value.The composition of copper-manganese is Mn:12% in the present embodiment, Ni:4%, and Cu: surplus, temperature coefficient are 10ppm, and thickness is 1.2mm, and width is 5.2mm, and the thickness of copper belt is 1.2mm, width is 17.5mm, is 10 in vacuum degree ^-2-10 ^-4Pa, anode voltage are to carry out electron beam welding under the condition of 30-150KV, form the bimetal band of red copper-copper-manganese-red copper, use die stamping then, adopt metal cutting that the thickness of resistive element is adjusted into 0.7mm, make accurate shunt resistor as shown in Figure 1.

Claims

1, a kind of accurate shunt resistor, form by the bus-bar that resistive element and employing copper plate are made, it is characterized in that described resistive element adopts temperature coefficient to be lower than the copper-manganese plate of 20ppm, has the temperature coefficient that forms by the electron beam welding fusion to be lower than transition copper-manganese-red copper alloy band of 50ppm between resistive element and bus-bar.

2, accurate shunt resistor according to claim 1 is characterized in that having installing hole and voltage output end on bus-bar.