CN203259241U

CN203259241U - Weighing unit of electronic balance

Info

Publication number: CN203259241U
Application number: CN 201320216631
Authority: CN
Inventors: 王杨
Original assignee: Sartorius Scientific Instruments Beijing Co Ltd
Current assignee: Sartorius Scientific Instruments Beijing Co Ltd
Priority date: 2013-04-26
Filing date: 2013-04-26
Publication date: 2013-10-30
Anticipated expiration: 2023-04-26

Abstract

A weighing unit of an electronic balance is characterized in that the weighing unit is composed of a weighing system, a circuit board, a balance resetting board, an aluminum alloy shielding cover, a substrate, a plastic housing with a conductive coating, etc. According to the weighing unit, multi-layer electromagnetic shielding protection is adopted, and an aluminum alloy housing is adopted as an inner housing. A conductive shielding coating is added in the outer plastic housing, and a grounding device is added. Furthermore all protective housing gaps are sealed by conductive aluminum strips. A protective cover is added at the end of a weighing pan. The balance resetting board is added in the weighing unit. After the circuit breaks down, the balance resetting board automatically rests for ensuring no stoppage in the weighing process. A heat conduction insulated conductive insulation pad is added for the weighing unit of the electronic balance, thereby preventing conduction of high temperature generated by electromagnetic wave to the inner part of the balance and reducing weighing precision. The weighing unit of the electronic balance transmits weighing data to a PC through an external serial port. The electronic balance is interfered when placed in an electromagnetic environment, and low accuracy of the measured valve is caused. Through the measures of multi-layer electromagnetic shielding protection, circuit anti-breakdown design, balance pan high-temperature insulation design, etc., the effect of external electromagnetic interference to weighing precision is maximally reduced.

Description

The scales/electronic balance weighing unit

Technical field:

The utility model relates to a kind of laboratory electronic balance, the especially specialized application a kind of scales/electronic balance weighing unit under strong electromagnetic electric field interference environment.

Background technology:

High Accuracy Electronic Balance has strict requirement to environment for use.Temperature, vibration, electromagnetic interference (EMI), humidity etc. all can have influence on the weighing result of balance, so can only use in laboratory environment.This has just limited the application of balance greatly.

Summary of the invention:

Goal of the invention of the present utility model is to provide a kind of electromagnetic screen, anti-scales/electronic balance weighing unit that crashes and have the isolated design of high temperature of increasing.

Goal of the invention of the present utility model mainly is achieved by following technical proposals:

A kind of scales/electronic balance weighing unit is characterized in that, this weighing unit adopts the protection of multilayer electromagnetic screen, and inner housing adopts Al-alloy casing, and inner housing wraps the aluminium sheet of magnetoelectric sensor and wiring board; The inside of outer plastic housing increases the conductive shield coating, increases earthing device; And the sealing of conduction aluminum strip is all used in all protection housing slits; The weighing plate termination increases over cap.Further, increased balance in this weighing unit and restarted plate, after circuit crashed, this restarts plate can autoboot.Further, electronic balance module weighing plate increases the isolated conduction of heat conduction trap-out tray.

This electronic balance adopts the anti-design of crashing of circuit.Design separately balance and restarted plate, autoboot after crashing, assurance weighing process is not ended.

The scale pan adopts the high temperature isolation design: increase the isolated conduction of heat conduction trap-out tray at electronic balance module weighing plate, the high temperature of avoiding electromagnetism to produce conducts to balance inside, affects weighing precision.

Improve via technique scheme, this Weighing system module places the domestic microwave furnace bottom, during weighing tray of microwave oven substance weight, can guarantee that weighing is accurate, and indicating value is stable.

Description of drawings

Accompanying drawing 1a one 1e is the product design figure of the utility model scales/electronic balance weighing unit, Fig. 1 a is the front view of product design, and Fig. 1 b is the rear view of product design, and Fig. 1 c is the structural drawing of this product conduction trap-out tray, Fig. 1 d is the vertical view of this product, and Fig. 1 e is product one-piece construction view;

Accompanying drawing 2a one 2d is the synoptic diagram of this scales/electronic balance weighing unit plastic casing and raises with the interior view behind the plastic casing of conductive coating, Fig. 2 a is the front view of plastic casing, Fig. 2 b is the rear view of plastic casing, Fig. 2 c is the weighing unit inner structure front view of raising plastic casing, and Fig. 2 d is the weighing unit inner structure rear view of raising plastic casing;

The component names of each accompanying drawing number representative is as follows in the accompanying drawing:

1, with the plastic casing of conductive coating; 2,5mm aluminium alloy base plate; 3, conduction trap-out tray; 4, pan of a steelyard; 5, weighing unit matrix; 6, aluminium alloy radome; 7, weighing unit wiring board.

Embodiment:

Below by embodiment, and by reference to the accompanying drawings, structure of the present utility model is done to describe further.

Electronic balance adopts the protection of multilayer electromagnetic screen, and inner housing adopts Al-alloy casing; The outer plastic housing adopts the inner conductive shield coating that increases, and increases earthing device; And all protection housing slits are all strictly with the sealing of conduction aluminum strip; The weighing plate termination increases over cap.Fixing circuit board and magnetoelectric sensor are fixed on the 5mm aluminium sheet.This aluminium sheet and Al-alloy casing, the plastics external conductive casing forms the double-layer seal galvanic circle, and simultaneously with whole frame grounds, and all protection housing slits all strictly seal with electric conductor.Cover the conduction trap-out tray at the scale pan simultaneously, reduce substantially outside electromagnetic interference to the impact of weighing precision.

Electronic balance is placed the multilayer electromagnetic shielding shell: with the Al-alloy casing parcel, seam crossing seals with the conduction aluminum strip respectively for magnetoelectric sensor and wiring board.Then seal the inner conductive shield coating that increases of plastic casing with plastic casing in whole electronic balance outside.Fixing circuit board and magnetoelectric sensor are fixed on the 5mm aluminium sheet.This aluminium sheet and Al-alloy casing, the plastics external conductive casing forms the double-layer seal galvanic circle, and simultaneously with whole frame grounds, and all protection housing slits all strictly seal with electric conductor.Cover the conduction trap-out tray at the scale pan simultaneously, reduce substantially outside electromagnetic interference to the impact of weighing precision.

The anti-design of crashing of circuit: on magneto-electric LOAD CELLS wiring board, designed separately balance and restarted plate, autoboot after crashing.Solved balance modular circuit system and use the situation that deadlock occurs in electromagnetic environment, assurance weighing process is not ended.

Scale pan high temperature isolation design: increase the conduction trap-out tray at electronic balance module weighing plate, this trap-out tray is made by heat-barrier material, and by the expansion space way, that reduces high ambient temperature conducts to balance inside, affects weighing precision.

Reduce substantially outside electromagnetic interference to the impact of weighing precision by these measures.

The client is with the weighing unit of our exploitation, and the light wave moisture tester that is installed in them is inner.The first half is micro-wave oven, is used for the heating measured object, oven dry moisture.The latter half is electric apparatus room and XX88 weighing unit.Very strong electric field and electromagnetic interference (EMI) are here arranged, and temperature variation is large.In such environment, the XX88 weighing unit still can guarantee measuring accuracy after tested, has reached customer requirement, and the design that we are described is successfully.

Claims

1. a scales/electronic balance weighing unit is characterized in that, this weighing unit adopts the protection of multilayer electromagnetic screen, and inner housing adopts Al-alloy casing, and inner housing is wrapping the aluminium sheet of magnetoelectric sensor and wiring board; The inside of outer plastic housing increases the conductive shield coating, increases earthing device; And the sealing of conduction aluminum strip is all used in all protection housing slits; The weighing plate termination increases over cap.

2. scales/electronic balance weighing as claimed in claim 1 unit is characterized in that, has increased balance in this weighing unit and has restarted plate, and after circuit crashed, this restarts plate can autoboot.

3. scales/electronic balance weighing as claimed in claim 1 or 2 unit is characterized in that, electronic balance module weighing plate increases the isolated conduction of heat conduction trap-out tray.