CN2924485Y - Hand-held digital-display track differential height detecting ruler sampling component - Google Patents

Abstract

The utility model provides a rail elevation difference detector. At present, when applied to the domestic line construction and regular detection, the workers still adopt the level sopped track rail rule for monomer operation due to lack of light and convenient digital display apparatus for substitution. Nevertheless, the utility model just relates to a digital display measuring instrument which is applied to measure the sampling of the track rail elevation difference and transfer the mechanical amount into the electric signal. The technical method designed to solve the key problem of how to sample the signal is that: according to the principle that if the heights of the liquid surfaces in the connection pipes are different from each other, the pressure of the liquid surfaces shall also be various, the parallel quad model built-in glass connection pipe is connected and filled with mercury of 1/2 of the pipe height; while the bottoms of the right and the left liquid columns are respectively provided with a pressure sensor of overall sealing structure and protected with the aluminum alloy hull, forming the sampling part to be fixed on the frank beam of the rule body; wherein, the pressure sensor sends out the pressure difference signal in the voltage varying form, as the sampling signal.

Description

Hand-held digital display track discrepancy in elevation detection ruler sample unit

Affiliated technical field

The utility model relates to the sampling apparatus that a kind of digital display is measured the track difference in height, is applicable to the sampling of track difference in height, and difference in height is converted into electric signal.

Background technology

Known air level track chi detects the track difference in height, causes artificial error easily, especially when the track discrepancy in elevation surpasses the air level scale, needs to use secondary chi compensation, can carry out the gamut reading, and therefore operation is very inconvenient.The key of the high difference of Digital Detecting track is how to carry out signal sampling, and requires the sample unit structure light, highly sensitive.

Summary of the invention

In order to realize that digitizing detects the track discrepancy in elevation, the utility model provides a kind of sample unit.This sample unit can be exported the high difference of track easily with the voltage signal form, handle for other single chip circuits.

The technical scheme that its technical matters that solves the utility model adopts is: the glass communicating pipe that a parallelogram pattern is set, interior water-filling silver medium, respectively adorn a pressure transducer in its fluid column bottom, left and right sides, communicating pipe and pressure transducer are protected with aluminum alloy casing, form sampling head; Sampling head is screwed on the aluminium alloy straight beam in a H type cross section, forms sample unit.When placing on the track of sample unit in the different discrepancy in elevation, because of the inclination of sample unit, will make in the sampling head pressure difference of two fluid column lower ends about communicating pipe, through pressure transducer with this pressure reduction with the output of change in voltage form, as sampled signal.

Ultimate principle is: when the sample unit both sides discrepancy in elevation is h, communicating pipe the level change of left and right pillar respectively be

$p_a=a^{\′}-b=\frac{1}{2}h$

$p_b=b^{\′}-b=-\frac{1}{2}h$

Wherein: the liquid level when b is horizontal level;

The liquid level of left side column when a ' tilted for communicating pipe;

The liquid level of the right column when b ' tilted for communicating pipe.

Sampled signal is with differential pressure p=p _a-p _b=1/2h-(1/2h)=output of h form.Horizontal level is as zero-bit, and output P value is greater than zero, and is then right high left low, be shown as on the occasion of; Output P value is less than zero, and then a left side is high right low, is shown as negative value.With the positive and negative height that can distinguish the track two ends of P value, the numerical value of P is the sampled value of the discrepancy in elevation.

The architectural feature of sample unit is: be made up of straight beam and sampling head two parts, both use screw attachment.Straight beam is the aluminium alloy extrusions in H type cross section; Sampling head is made up of back protecting sheathing, glass communicating pipe, pressure transducer, mercury, fluid sealant, output line, sunk screw, preceding protecting sheathing, silica gel liner.Side has semi-circular recesses in the forward and backward protecting sheathing, and glass communicating pipe embeds in the groove of protecting sheathing, serves as a contrast between the two with the silica gel liner; Two MPX-10 of Motorola pressure transducers respectively with communicating pipe the left and right pillar lower end liquid level directly contact, and seal with fluid sealant.Forward and backward two protecting sheathings are fastening with sunk screw.

The beneficial effects of the utility model are: output signal is the differential pressure amount of left and right sides fluid column level change, i.e. 2 times fluid column level change pressure, so output signal is strong, precision is high; The sampling head main devices only is glass communicating pipe, pressure transducer, mercury, and is simple in structure.

Description of drawings

Below in conjunction with drawings and Examples the utility model is further specified.

Fig. 1 is the installation site (face) of sampling head on straight beam.

Fig. 2 is an embodiment sampling head structure.This figure draws to face complete section, has reflected the assembly relation and the key dimension of each assembly in it.

Fig. 3 is embodiment sampling head transverse section (the A--A section of Fig. 2), amplifies the technique of painting, is further replenishing Fig. 2.

Among the figure: 1. straight beam, 2. sampling head, 3. screw, 4. back protecting sheathing, 5. glass communicating pipe, 6. pressure transducer, 7. mercury, 8. fluid sealant, 9. output line, 10. sunk screw, protecting sheathings before 11., 12. silica gel liners.

Embodiment

The left and right pillar spacing distance of communicating pipe (5) is big more, and sensitivity is high more, but sampling head (2) physical dimension will be big more.The present embodiment left and right pillar is taken as 500mm at interval, because of the rail reference center distance is 1505mm, is 1: 3.01 (1505 ÷ 500=3.01) so make scale down.

Communicating pipe, (5) material was a glass, and caliber causes easily that too slightly liquid level ripples, and makes data presentation longer stabilization time, too carefully can make resistance to flow excessive, causes the loss of flood peak.The present embodiment bore is φ 2.5mm.

Pressure transducer (6) model is the MPX-10 of a Motorola silicon pressure sensor, 2 of quantity, respectively with communicating pipe the left and right pillar lower end liquid level directly contact, and seal with fluid sealant (8).Its effect is that the liquid level pressure difference is converted into voltage signal.

Voltage signal is calculated as follows:

1. the sensitivity k=3.5mV/KPa of MPX-10 silicon pressure sensor when power supply (5V).

2. as the wide 1505mm of full track, when the rail level discrepancy in elevation changed 1mm, sampling head both sides discrepancy in elevation h changed 1/3.01=0.332mm.

3. every silicon pressure sensor output voltage values:

∵ 1 atmospheric pressure=0.1MPa=100KPa

1mmHg＝0.1316KPa

∵ sampling head both sides discrepancy in elevation h changes 0.332mm, and left and right pillar respectively changes 1/2h.

Every silicon pressure sensor output voltage of ∴:

U＝k×1/2h×0.1316＝3.5×1/2×0.332×0.1316＝0.0765mV

4. present embodiment with the left and right pillar differential pressure as output signal, so the differential pressure output voltage is 2U=2 * 0.0765 mV=0.153 mV

Claims (3)

1. a hand-held digital display track discrepancy in elevation detection ruler sample unit is made up of straight beam and sampling head two parts, and both use screw attachment, it is characterized in that: straight beam is the aluminium alloy extrusions in H type cross section; Sampling head is made up of back protecting sheathing, glass communicating pipe, pressure transducer, mercury, fluid sealant, output line, sunk screw, preceding protecting sheathing, silica gel liner; By two pressure transducers the pressure reduction of glass left and right sides fluid column in communicating pipe is converted to electric signal.

2. sample unit according to claim 1, its sampling head feature is: forward and backward protecting sheathing inboard is processed with semi-circular recesses, and glass communicating pipe embeds in the groove of protecting sheathing, serves as a contrast between the two with the silica gel liner; Two MPX-10 of Motorola pressure transducers respectively with communicating pipe the left and right pillar lower end liquid level directly contact, and seal with fluid sealant; Forward and backward two protecting sheathings are fastening with sunk screw.

3. the feature of glass communicating pipe is in the sample unit according to claim 1, its sampling head: the parallelogram pattern, and bore φ 2.5mm, external diameter φ 6mm, limit, the left and right sides is the liquid level column, and bottom is the liquid level passage, and the top is the inner air tube circulation road; Inject mercury in communicating pipe as medium, injecting amount of mercury is 1/2 column height.

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