CN201210078Y

CN201210078Y - Flame-proof type weighing sensor

Info

Publication number: CN201210078Y
Application number: CNU2008200024881U
Authority: CN
Inventors: 葛学海; 谢凡
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-01-27
Filing date: 2008-01-27
Publication date: 2009-03-18
Anticipated expiration: 2018-01-27

Abstract

The utility model relates to a flameproof type weighing sensor for a coal mine in underground. A flameproof enclosure with certain strength is arranged outside an ordinary tension weighing sensor, so that when flammable and explosive gases are ignited by the electric spark of the sensor circuit in the flameproof enclosure and then explode, the flame and high temperature gas can not be spread out of the flameproof enclosure to ignite the flammable and explosive gases outside the flameproof enclosure. Therefore, the flameproof type weighing sensor can be used in the environment with flammable and explosive gases such as the gas, coal dust and the like in the coal mine in underground, and the electric spark of the weighing sensor circuit can not cause the gas explosion, coal dust explosion, burning and other accidents.

Description

The flame-proof type LOAD CELLS

(1) technical field

The utility model patent relates to a kind of special LOAD CELLS, especially for the explosion-proof sensor under the coal mine.It contains under coal mine that high gas, coal dust etc. are inflammable, do not have when using in the explosive atmosphere and ignite, ignite danger inflammable, explosion hazard gases.

(2) background technology

The common pulling force sensor of weighing is that the pulling force sensor upper end is fixing, and the lower end hangs weight.Weight makes the foil gauge of sensor produce strain, changes its electrical parameter values, uses special circuit to measure the change amount of this electrical quantity, draws weight of heavy by certain conversion.In use, short circuit heating or starting the arc sparking fault may appear in the circuit of sensor, inflammable, the explosion hazard gases generation fire that can ignite, even the accident of blasting.So common pulling force sensor can not be used for containing gas under the coal mine, coal dust etc. are inflammable, in the environment of explosion hazard gases.

(3) summary of the invention

The purpose of this utility model is to provide a kind of novel flame-proof type LOAD CELLS, overcomes the shortcoming of prior art.It is to install a special flameproof enclosure outside the common pulling force sensor of weighing additional, in, the cavity of explosion hazard gases in flameproof enclosure inflammable when gas, coal dust etc. by the electric spark of fault sensor light, explosion time, flame and high-temperature gas can not be diffused into the flameproof enclosure outside, there are not the flame proof shell that ignites outer inflammable, possibility that explosion hazard gases has an accident, thus the thorough solution explosion-proof problem that pulling force sensor uses under coal mine of weighing.

Its solution is: install a special flameproof enclosure additional in common LOAD CELLS outside, the upper end and the flameproof enclosure of sensor are fixed together, and by being bolted on the support; The lower end and the piston of sensor are fixed, and hang weight by the bolt connection.Along with the difference of weight weight, be added in the pulling force difference of sensor lower end, the deformation quantity difference that sensor produces, the sensor internal foil gauge converts different deformation quantities to electric signal, measures weight of heavy.

When hanging the weight of Different Weight, the piston that is fixed on the sensor lower end moves up and down with the sensor lower end, but remain in the flameproof enclosure plunger shaft, form the closed cavity that certain tolerance clearance is arranged, sensor is enclosed in the explosion-proof chamber with flameproof enclosure.When the circuit of sensor was short-circuited overheated or electric spark occurs and light flammable explosive gas in the explosion-proof chamber, piston was after the promotion of gases at high pressure is issued to maximum displacement, and roof pressure is on bottom end cover.Because flameproof enclosure, piston, bottom end cover and set bolt all have enough intensity, flammable explosive gas can be not destroyed when the explosion-proof chamber implode, so the flame of explosion-proof chamber implode and high-temperature gas are closed in the explosion-proof chamber, can not splash, can only outwards spray by the gap between flameproof enclosure, piston and bottom end cover.Because the flame-out effect and the cooling effect in gap, the gas that is sprayed onto the flameproof enclosure outside can not have flame, and temperature also reduces, has not had the ability of outer inflammable, the explosion hazard gases of the flame proof shell that ignites.The also very fast meeting of flame in the explosion-proof chamber is extinguished because of oxygen or combustible gas exhaust.Therefore to use in inflammable, explosive atmosphere be safe to the flame proof LOAD CELLS, can not ignite, actuation gas, coal dust etc. are inflammable, the accident of explosion hazard gases, can be used for the environment that coal mine gas, coal dust are assembled.

(4) description of drawings

Fig. 1 is the main cut-open view of flame-proof type LOAD CELLS.

(5) embodiment

Embodiment of the present utility model is described in detail in conjunction with the accompanying drawings.

The upper end of pulling force sensor 13 is fixed together by hexagon head bolt on special 12 and flameproof enclosure 8 in Figure of description 1; Last hexagon head bolt 12 usefulness hanger bolts 11 are fixed on the fixed support; Last hexagon ring retaining cover 10 is enclosed within on the hexagon head bolt 12, and is connected with flameproof enclosure 8 with screw 9.The lower end of pulling force sensor 13 is with special down hexagon head bolt 2 fixed pistons 5; Piston 5 gaps connect flameproof enclosure 8; Flameproof enclosure 8 lower port are with bottom end cover 6, and bottom end cover 6 is fixed on the flameproof enclosure 8 by screw 7.Following hexagon ring retaining cover 4 is enclosed within down on the hex bolts 2, and is fixed on the piston 5 with screw 3.Weight is hung on following hex bolts 2 by Hanging bolt 1.

The upper end of pulling force sensor 13 is by last hexagon head bolt 12, and hanger bolt 11 is fixed on the support; The lower end of pulling force sensor 13 is by Hanging bolt 1, following hexagon head bolt 2 is hung weight, the pulling force that pulling force that weight is downward and support make progress acts directly on the pulling force sensor 13, make sensor 13 that deformation take place, deformation takes place with sensor 13 in the foil gauge of sensor 13 inside, and this deformation quantity converted to corresponding electric signal, circuit by sensor internal amplifies, arrangement, export from line outlet 15 through connection terminal 14 by lead-in wire, handle through subsequent conditioning circuit, draw the weight of respective weight.

Flameproof enclosure 8 and piston 5 are by last hexagon head bolt 12, and following hexagon head bolt 2 is pressed on pulling force sensor 13 upper/lower terminals; The piston 5 of lower end is because of weight varies in weight, and sensor 13 deflection differences move up and down with sensor 13 lower ends.Because tolerance clearance is bigger between the plunger shaft of flameproof enclosure 8 and the piston 5, do not contact substantially each other, so flameproof enclosure 8 and piston 5 are not subjected to external force in the whole weighing process, can not influence the measuring accuracy of sensor 13.

5 in flameproof enclosure 8 and piston are formed the flame proof cavity that the sealing of certain tolerance clearance is arranged, and pulling force sensor 13 is enclosed in the flame proof cavity.The extension line of sensor 13 is drawn through the special line outlet 15 that has rubber blanket, and the gap of line outlet and extension line is by rubber seal, and has enough explosion-proof intensity.The circuit of pulling force sensor 13 breaks down in the course of work, produces overheated and electric spark, ignite in the explosion-proof chamber inflammable, when explosion hazard gases is blasted, the gases at high pressure of generation are pushing piston 5 at first downwards; Because piston 5 has enough axial lengths in flameproof enclosure 8 plunger shaft, when piston 5 is pulled to bottom, when pulling by following hexagon head bolt 2 or pulling the acting in conjunction that stops with bottom end cover 6 and stop to move down because of sensor 13 because of pulling force sensor 13, the explosion-proof chamber that flameproof enclosure 8 and piston are 5 is still the cavity of a sealing, and 5 in flameproof enclosure 8 and piston still keep the composition surface that flame proof requires that meets more than the 9mm.Because line outlet 15 seals, flameproof enclosure 8 also has enough intensity, can be not destroyed, so, the 0.05mm that gases at high pressure can only be reserved between flameproof enclosure 8 and piston 5 to the gap of 0.5mm or pulling force sensor 13 and flameproof enclosure 8, go up hexagon head bolt 12 and pulling force sensor 13, piston 5, spray the poorly sealed slit the hexagon head bolt 2 down.These gaps and surface of contact all are qualified flame proof gap and explosion suppresion surfaces.Because the flame-out effect and the cooling effect in gap, the gas of ejection does not have flame, and it is lower that temperature has also been fallen, and has not possessed to light that flame proof shell outside is inflammable, the ability of explosion hazard gases; The also very fast meeting of flame in the explosion-proof chamber is extinguished because of oxygen or combustible gas exhaust.Therefore can not ignite, actuation gas, coal dust etc. are inflammable, the accident of explosion hazard gases.Following hexagon ring retaining overlaps 4, upward hexagon ring retaining cover 10 is enclosed within down hexagon head bolt 2, goes up on the hexagon head bolt 12, their hex hole matches with the hexagon head of bolt, its effect is to prevent down that hexagon head bolt 2, last hexagon head bolt 12 in use move back silk, the slit is increased, cause and lose quick-fried (lose flame-out and cooling effect no longer flame proof) because of the slit is excessive.So it is safe that flame-proof type LOAD CELLS of the present utility model is used for the environment of flammable explosive gas gatherings such as coal mine gas, coal dust, gas, coal dust burning and explosion accident can not take place.

The utility model provides a kind of flame-proof type LOAD CELLS, it is simple in structure, and is safe and reliable, does not influence the measuring accuracy of sensor, can be widely used under the coal mine in the various online weighing equipment, solve and under coal mine, used electronic equipment to carry out the difficult problem of Weighing.

Claims

1, a kind of flame-proof type LOAD CELLS, it is characterized in that common strain pulling force sensor (13) places in the explosion-proof chamber of flameproof enclosure (8), the upper end of pulling force sensor (13) is fixed together by fastening bolt (12) and flameproof enclosure (8), the lower end of pulling force sensor (13) is fixed together by fastening bolt (2) and piston (5), bottom end cover (6) is enclosed within on flameproof enclosure (8) lower port, and is fixed on the flameproof enclosure (8) with screw (7).

2, flame-proof type LOAD CELLS as claimed in claim 1, it is characterized in that piston (5) is in the plunger shaft of flameproof enclosure (8) lower end, can move up and down with pulling force sensor (13) lower end, piston (5) adopts clearance fit with the plunger shaft of flameproof enclosure (8), and gap size is between 0.05mm to 0.5mm.

3, flame-proof type LOAD CELLS as claimed in claim 1, it is characterized in that bottom end cover (6) has moved down position-limiting action to piston (5) in flameproof enclosure (8) plunger shaft, make piston (5) when lowest positions, the axial length that puts in flameproof enclosure (8) plunger shaft is not less than 9mm.

4, flame-proof type LOAD CELLS as claimed in claim 1 is characterized in that the upper and lower fastening bolt (12) of sensor (13), the center of (2) have the tapped blind hole of certain depth, connects support or hangs weight by screw (11), (1).