CN87102790A - Rear-mounted vehicle for automating measurement of road sinking - Google Patents
Rear-mounted vehicle for automating measurement of road sinking Download PDFInfo
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- CN87102790A CN87102790A CN 87102790 CN87102790A CN87102790A CN 87102790 A CN87102790 A CN 87102790A CN 87102790 CN87102790 CN 87102790 CN 87102790 A CN87102790 A CN 87102790A CN 87102790 A CN87102790 A CN 87102790A
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Abstract
The invention relates to the measuring apparatus of pavement deflection value, drag formula pavement deflection to measure the invention of car automatically after particularly, have test the speed fast, precision is high, wait advantage accurately and reliably.The measuring staff fulcrum of this invention measuring mechanism is fixed on the datum line beam, the measuring staff front portion has one section negative area can extend through automobile back wheel center, afterbody smoothly electromagnetic clamp is housed is connected with displacement transducer on the datum line beam, datum line beam and terrain be rigid body movably, its traffic direction is limited by the guide rail of guiding mechanism, and guiding mechanism is connected with automobile by articulating steering mechanism.The surveying work program is by automatic controlling system.
Description
The present invention is the automatic measurer that is used to measure the pavement deflection value.
For these years, various countries adopted various test methods to measure the deflection value of road once.At present, abroad produced with the similar measuring apparatus of the present invention Beckman beam flexure analyzer and " Lacroix " flexure recorder etc. have been arranged.Wherein the Beckman beam is used the earliest, also relatively extensively.But this instrument is the head of measuring staff to be put in advance cross the place of 200 millimeter forward, wheel center in the automobile back wheel gap, after automobile is started forward by static acceleration, the difference in height (deflection value) of the ground resilience that measuring staff picked up, because of tire is that acceleration with automobile changes to ground pressure, so the accuracy of the deflection value of surveying is influenced by this; And, operating personnel many (more than ten people), labour intensity is big, and it is also lower to measure efficient, even well-trained measurement group also can only be carried out 50 to 80 measuring points in one day.
" Lacroix " flexure recorder (LOCROIX DEFLECTORGRAPH) of people such as the Lacroix development of France bridge research institute is the higher equipment of road flexure efficient of measuring at present.This forward type benkelman beams deflectometer is placed on below the automobile chassis and works on the ground measuring beam (being datum line beam again), because automobile is when operation, before and after tire the fluctuating situation that causes of face effect is very complicated over the ground, the benchmark effect of datum line beam is affected, must increase measure error.Though, improving structural evolution from it, they attempt to seek several touchdown points under datum line beam, and in order to offset the influence that datum line beam is subjected to, the result also fails thoroughly to solve.
Domestic also have several families once developed with the present invention similarly after drag the formula autodeflectometer, but because they do not notice the mechanics principle that follow in development work, note detecting with switch technology in reliable measure.Therefore,, can not prove its numerical reliability, also not have the reliable technique means to guarantee, so also can not get ideal results from principle to deflection value record, that print.
Task of the present invention is: according to comprehensive know-why, by a series of technological means, in order to solve aforementioned existing problems, provide a kind of test the speed fast, precision is high, accurately and reliably, desirable be suitable for after drag formula pavement deflection to measure car automatically.Its measuring speed can reach 2-5 kilometer/hour, and accuracy can reach the 2/100-4/100 millimeter.
Task of the present invention is achieved in that measurement car of the present invention except the truck supporting with it, and its primary structure is partly formed by articulating steering mechanism, guiding mechanism, datum line beam, measuring mechanism and automatic control system etc.These invention primary structure characteristics are: the front portion of measuring mechanism has one section negative area can extend through the automobile back wheel center smoothly, the rear portion of measuring mechanism has a measuring staff fulcrum to be fixed on the datum line beam, the afterbody of measuring mechanism is equipped with electromagnetic clamp, and by it measuring mechanism is linked to each other with displacement transducer on being contained in datum line beam.The traffic direction of datum line beam is controlled by the guide rail that the guiding electromagnet on it and directive wheel are subjected to guiding mechanism, and guiding mechanism is connected with automobile chassis afterbody crossbeam by articulating steering mechanism.In surveying work, whole surveying work process realizes its automatic control by automatic control system entirely.When measuring, measure the automobile chassis of car as lengthening, form an organic whole with automobile.In when operation, measure car and become the trailer that hangs over automobile tail again, as on the guide rail frame that again its datum line beam is hung on guiding mechanism the time, measure car and just can move freely as common trailers.When parking, after remove measuring being connected of car and automobile, the measurement car can be parked on the ground again evenly, and can rotate freely.This design scheme, in connection, the measurement of unit, move and park, when shifting all easily, be suitable for.
Below with reference to accompanying drawing one embodiment of the present of invention and concrete structure principle, performance characteristics, technological means and the course of work are described in further detail.
Accompanying drawing 1 is the primary structure schematic diagram of overall arrangement of the present invention.
Accompanying drawing 2 is vertical views of Fig. 1.
Accompanying drawing 3, accompanying drawing 4 are course of work automatically controlled circuit diagrams of the present invention.
Drag formula pavement deflection to measure the general structure of car automatically after Fig. 1, Fig. 2 have described, it is mainly partly formed by articulating steering mechanism (1), guiding mechanism (2), datum line beam (3), measuring mechanism (4) and automatic control system etc.Below with its primary structure principle of division, performance characteristics and technological means.
The design feature that articulates steering mechanism (1) is a pin type, and it is a kind of guide rail frame (5) and automobile chassis crossbeam in the guiding mechanism (2) are rigidly connected, and can become the dual-functioning mechanism of rotating disc type connection again.One end of this mechanism base (6) is clamped on the automobile chassis crossbeam by clamping plate (7), and the other end flexibly connects by cylindrical bearing pin (8) and the cross-arm (9) above it; And the outer seat of the articulated pin at cross-arm (9) two ends (10) is connected with guide rail frame (5) in the guiding mechanism (2) by articulating bearing pin (11) again.When guide rail frame (5) was connected as rotating disc type with automotive frame, cross-arm (9) was gone up rotatable 30 ° at base (6).When measuring, by two conical latches (12) cross-arm (9) and base (6) are locked, the guide rail frame (5) of guiding mechanism (2) and automotive frame are rigidly connected, as the automobile chassis of lengthening.When operation, again two conical latches (12) are taken out, at this moment, guiding mechanism (2) resembles and has become the trailer that hangs over automobile tail.When going up as the guide rail frame (5) that again datum line beam (3) is hung on guiding mechanism (2) by four suspension rods (13) on it, then guiding mechanism (2) just can move freely as common trailers.Therefore, this technological means has just solved the measurement car in measurement and operating contradiction.In addition, when measuring car and park, when remove measure being connected of car and automobile after, whole measurement car and can rotate freely just by two tail wheels (15) support of two movable supporting wheels (14) of guide rail frame (5) front end and rear end on the ground.
Guide rail frame (5) in the guiding mechanism (2) is the framework of being made by rigid material, and it articulates steering mechanism (1) by pin type and is connected with automobile chassis afterbody crossbeam.The traffic direction of datum line beam (3) is exactly controlled by the guide rail (18) in the guide rail frame (5) by 8 guiding electromagnets (16) above it and 8 directive wheels (17).For absorbing the vibrational energy of datum line beam (3), in the front portion of guide rail frame (5) collision bumper (19) is housed, its role is to: when datum line beam (3) advances to when requiring the travel switch K in positive stop block (20) hole on the datum line beam (3) with the speed faster than automobile
2(21), make the outage of motor (22) and guiding electromagnet (16); Simultaneously, datum line beam (3) is acutely slowed down, and the spring (23) in the snubber (19) is compressed, to absorb the vibrational energy of datum line beam (3).According to
This relational expression, Control of Automobile speed V
2, regulate datum line beam (3) speed of service V
1, select the spring (23) of proper stiffness K to make snubber (19), the maximum compressibility δ m that can ask.Select for use among the present invention more than the δ m=200 millimeter.Behind datum line beam (3) cushion at collision (19), snubber (19) is compressed 200 millimeter on the one hand, and oppositely impulse force forces datum line beam (3) to swash and reduces sharply speed on the other hand, and automobile falls back relatively, when returning 200 millimeter, and travel switch K
2(21) reset, begin brake, datum line beam (3) is static substantially stable this moment, and the gauge head (24) of measuring mechanism (4) front end also is in 400 millimeter places, the place ahead, automobile back wheel center, again through delaying time 0.2-0.3 second, also before the wheel center, this moment, the opening entry deflection value was reliable to gauge head (24) as can be known.
Datum line beam (3) is a rigidity roof beam structure movably, and it is accurately to deliver to the parts that require the position to the measuring staff (25) in the measuring mechanism (4).Requirement to datum line beam (3) is: the first, to deliver to measuring staff (25) rapidly and accurately the position of requirement.For this reason, 8 directive wheels (17) are housed, when advancing, directive wheel (17) are pulled in the upright position, form limit channels by 8 guiding electromagnets (16) in the top of datum line beam (3).When the traffic direction of datum line beam (3) in a single day departs from the automobilism direction, hang over guide rail (18) in the guiding mechanism (2) of automobile tail and just promote to be pressed onto directive wheel (17) on the guide rail (18), adjust the traffic direction of datum line beam (3).The characteristics of this guiding mechanism (2) are: produce bigger moment by less electromagnet pulling force, can reliably adjust the traffic direction of the driving wheel (26) on the datum line beam (3) exactly.Second, when opening entry flexure curve, datum line beam (3) must be in and stop vibration, measuring staff fulcrum (27) does not have change in displacement to ground, and the touchdown point of datum line beam (3) (being driving wheel (26) and moving runner (28)) is not subjected to the stable state of ground flexure variable effect.Like this, gauge head (24) just can pick up pure deflection value.For reaching this purpose, the technological means that the present invention taked has two: one, and datum line beam (3) is made rigid body, and measuring staff fulcrum (27) is not changed to elasticity does not take place between the ground; The 2nd, datum line beam (3) terrain (being driving wheel (26) and moving runner (28)) also make rigid body, and moving runner (28) is loaded at a distance of vertical about 2.4 meters of gauge head (24), locate for horizontal about 0.35 meter.This binomial technological means is that forefathers do not find.The argument that must make rigid body to datum line beam (3) is: when a system of constrained particle moved, the active force system, the constraint reaction system that act on this system of material points formed a balanced system of force in form with the inertial system of system of material points.Be ∑ Fi+ ∑ Ni+ ∑ Gi=0
Become in the static process by motion at datum line beam (3), the constraint reaction that is added in direction of advance on the road wheel is eliminated, if usefulness is resilient wheel, to therefore shape take place and and then change, this transformation period reached more than 18 seconds, ran through whole measuring process, it is reacted to the change curve of gauge head (24), just similar to the flexure curve, be difficult for finding that its variable quantity is the 5/100-1 millimeter.This is a kind of surprising interfering signal that forefathers did not prove its existence.Because domestic existing is measured car (datum line beam), dress be elastic wheel, so the deflection value that records is not pure.
Also be equipped with on datum line beam (3) and drip mark mechanism (29), this mechanism mainly is made up of paint can (30) and electromagnetic valve (31).Its effect is: when the deflection value of finding survey mark surpasses prescribed limit, press and drip lacquer switch (at driver's cabin), lacquer liquid is promptly wandered ground from valve opening, becomes mark, searches for the inspection personnel.
The measuring staff (25) of measuring mechanism (4) is the member similar to the Beckman beam, and its measuring staff fulcrum (27) is fixed on the datum line beam (3), is put in the automotive wheels crack by its front end gauge head (24) and picks up deflection value.The characteristics of measuring mechanism of the present invention (4) are: have one section negative area (32) can extend through 600 millimeters at automobile back wheel center smoothly in the front portion of measuring staff (25), this is to reach datum line beam (3) and measuring staff (25) had enough quiescent times before entering surveying record, to avoid a technological means of vibration interference.Afterbody at measuring mechanism (4) also is equipped with electromagnetic clamp (33), during measurement, by it measuring staff (25) and the displacement transducer (34) that is contained on the datum line beam (3) is coupled together.Measure and finish, the chuck (35) of electromagnetic clamp (33) front end opens, and avoids measuring mechanism (4) to draw bad displacement transducer (34) on the one hand, and the fuse of holding position displacement sensor (34) was near zero point on the one hand.Produce displacement for fear of displacement transducer (34) when being subjected to clamping, depart from zero point excessive and influence range or measurement result, technological means of the present invention is: electromagnetic clamp (33) adopts the way on face of cylinder chuck (35) clamping plane (36).Plane (36) is connected with displacement transducer pull bar (39) by reed (37), joint (38).This measure has also reduced when clamping because of the eccentric resistance that produces.
Fig. 3, Fig. 4 also describe the course of work of the present invention and automatic control system thereof in detail in conjunction with Fig. 1, Fig. 2, and its switch board (40) is loaded on the datum line beam (3).When automobile is made uniform motion in the measurement location, press power control switch K (41) (at driver's cabin), magnetic starter C
1(42) power cathode (43) is connected in action.Be pressed onto travel switch K in the V-shaped groove (45) on the datum line beam (3) at the wishbone (44) of guiding mechanism (2) afterbody
1(46) time, magnetic starter C
2(47) energising action, 8 guiding electromagnets (16) energising work; Motor D (22) operation of switching on.When datum line beam (3) is run into collision bumper (19) to be higher than the quick operation of automobilism speed, travel switch K
2(21) connect J
1The circuit of relay (48), C
2(47) latching circuit is opened, guiding electromagnet (16) and motor (22) outage; J
2Relay (49) and SJ time-delay relay (50) and K
2(21) normally closed point is connected.This moment, collision bumper (19) was compressed 200 millimeter because of inertia.Swash play at datum line beam (3) and decelerate to collision bumper (19) when resetting, K
2(21) connect J again
2(49), the circuit of SJ (50), brake solenoid (51) energising work, datum line beam (3) begin brake, and SJ (50) delays time through 0.2-0.3 second, make electromagnetic clamp electromagnet (52) energising work, measuring staff (25) and displacement transducer (34) are coupled together; Simultaneously, recorder or microprocessor (53) (at driver's cabin) are started working.Automobile at the uniform velocity advances, and when the movable plate washer (54) in the wishbone (44) is run into tail switch (55) on the datum line beam (3), opens J
1The latching circuit of relay (48), recorder or microprocessor (53) quit work, and electromagnetic chuck (35) opens, and finishes the one-shot measurement writing task.When wishbone (44) reentered V-shaped groove (45), above-mentioned work circulated.
Claims (7)
1, a kind of measuring apparatus of measuring the pavement deflection value, drag formula pavement deflection to measure car automatically particularly, being equipped with one one on it can be connected with the automobile chassis crossbeam, the other end then is connected with the guiding mechanism [2] of measuring car articulates steering mechanism [1], below guiding mechanism [2], also have a datum line beam [3] and dress measuring mechanism [4] and automatic control system thereon, the invention is characterized in:
(a) articulate the pin type dual-functioning mechanism that steering mechanism [1] adopts cylindrical bearing pin [8] and conical latch [12] to combine.
(b) in guiding mechanism [2], be provided with guide rail frame [5], and the collision bumper [19] of spring is housed in its front portion, and the maximum compressibility δ of the spring [23] of snubber [19]
mSelect for use more than 200 millimeters.
(c) datum line beam [3] and terrain (driving wheel [26] and moving runner [28]) be movably rigid body.
(d) having one section negative area [32] can extend through automobile back wheel center 600 millimeter, rear portion smoothly in measuring staff [25] front portion of measuring mechanism [4] has a measuring staff fulcrum [27] and is fixed in that datum line beam [3] is gone up, afterbody is equipped with electromagnetic clamp [33].
(e) sequence circuit of automatic control system is: when automobile is made uniform motion in the measurement location, press power control switch K[41], magnetic starter C
1[42] power cathode [43] is connected in action.Be pressed onto travel switch K in the V-shaped groove [45] on the datum line beam [3] at the wishbone [44] of guiding mechanism [2] afterbody
1[46] time, magnetic starter C
2[47] energising action, guiding electromagnet [16] energising work; Motor D[22] the energising operation.When datum line beam [3] is run into collision bumper [19] to be higher than the quick operation of automobilism speed, travel switch K
2[21] connect J
1The circuit of relay [48], C
2[47] latching circuit is opened, guiding electromagnet [16] and motor D[22] outage; J
2Relay [49] and SJ time-delay relay [50] and K
2[21] normally closed point is connected.This moment, collision bumper [19] was compressed 200 millimeter because of inertia.Swash play at datum line beam [3] and decelerate to collision bumper [19] when resetting, K
2[21] connect J again
2[49], SJ[50] circuit, brake solenoid [51] energising work, datum line beam [3] begins brake, SJ[50] delay time second through 0.2-0.3, make electromagnetic clamp electromagnet [52] energising work, measuring staff [25] and displacement transducer [34] are coupled together; Simultaneously, recorder or microprocessor [53] are started working.Automobile at the uniform velocity advances, and when the movable plate washer [54] in the wishbone [44] is run into tail switch [55] on the datum line beam [3], opens J
1The latching circuit of relay [48], recorder or microprocessor [53] quit work, and electromagnetic chuck [35] opens, and finishes the one-shot measurement writing task.
2, measurement car according to claim 1 is characterized in that: when measuring, the traffic direction of datum line beam (3) is controlled by the guide rail (18) that the guiding electromagnet (16) on it and directive wheel (17) are subjected to guiding mechanism (2) both sides.
3, measurement car according to claim 1 is characterized in that: the electromagnetic clamp (33) that is loaded on measuring staff (25) afterbody is to adopt the way on face of cylinder chuck (35) clamping plane (36) and by reed (37) etc. measuring staff (25) is connected with displacement transducer pull bar (39).
4, measurement car according to claim 1 is characterized in that: the moving runner (28) on the datum line beam (3) is installed at a distance of vertical about 2.4 meters of gauge head (24), locates for horizontal about 0.35 meter.
5, measurement car according to claim 1 is characterized in that: at datum line beam (3) but on the mark survey mark is housed deflection value drip mark mechanism (29) when surpassing prescribed limit.
6, measurement car according to claim 1 is characterized in that: when operation, datum line beam (3) can be hung on the guide rail frame (5) of guiding mechanism (2) by the suspension rod on it (13).
7, according to claim 1 and 6 described measurement cars, it is characterized in that: the front end at the guide rail frame (5) of guiding mechanism (2) is equipped with support wheel (14), tail wheel (15) is equipped with in the rear end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 87102790 CN87102790A (en) | 1987-04-10 | 1987-04-10 | Rear-mounted vehicle for automating measurement of road sinking |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 87102790 CN87102790A (en) | 1987-04-10 | 1987-04-10 | Rear-mounted vehicle for automating measurement of road sinking |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN87102790A true CN87102790A (en) | 1988-01-20 |
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ID=4814120
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 87102790 Pending CN87102790A (en) | 1987-04-10 | 1987-04-10 | Rear-mounted vehicle for automating measurement of road sinking |
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| Country | Link |
|---|---|
| CN (1) | CN87102790A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105648883A (en) * | 2016-02-04 | 2016-06-08 | 江苏恒达工程检测有限公司 | Automatic deflection detecting device based on pavement |
| CN107217577A (en) * | 2017-07-10 | 2017-09-29 | 长安大学 | The continuous automatic backman beam mechanism of vehicular |
| CN109356008A (en) * | 2018-11-01 | 2019-02-19 | 河海大学 | The drop hammer deflection meter of continuous measurement pavement deflection |
| CN109373876A (en) * | 2018-10-25 | 2019-02-22 | 浙江润达检测科技有限公司 | A kind of evenness of road surface detection device |
| CN109520399A (en) * | 2019-01-18 | 2019-03-26 | 南县伟业机械制造有限公司 | A kind of paddy-field flattening degree detection system |
| CN109900193A (en) * | 2019-04-02 | 2019-06-18 | 嘉兴古辛达贸易有限公司 | A kind of Detection System for Bridge |
| CN113638293A (en) * | 2021-08-11 | 2021-11-12 | 齐爱娴 | Road and bridge strength detection device |
| CN114808689A (en) * | 2022-05-19 | 2022-07-29 | 大连理工大学 | Detection vehicle for extracting modal parameters of bridge |
-
1987
- 1987-04-10 CN CN 87102790 patent/CN87102790A/en active Pending
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105648883A (en) * | 2016-02-04 | 2016-06-08 | 江苏恒达工程检测有限公司 | Automatic deflection detecting device based on pavement |
| CN107217577A (en) * | 2017-07-10 | 2017-09-29 | 长安大学 | The continuous automatic backman beam mechanism of vehicular |
| CN107217577B (en) * | 2017-07-10 | 2019-07-16 | 长安大学 | The continuous automatic backman beam mechanism of vehicular |
| CN109373876A (en) * | 2018-10-25 | 2019-02-22 | 浙江润达检测科技有限公司 | A kind of evenness of road surface detection device |
| CN109373876B (en) * | 2018-10-25 | 2021-07-09 | 浙江润达检测科技有限公司 | Road surface flatness detection device |
| CN109356008A (en) * | 2018-11-01 | 2019-02-19 | 河海大学 | The drop hammer deflection meter of continuous measurement pavement deflection |
| CN109356008B (en) * | 2018-11-01 | 2021-07-02 | 河海大学 | Drop hammer type deflectometer for continuously measuring pavement deflection |
| CN109520399A (en) * | 2019-01-18 | 2019-03-26 | 南县伟业机械制造有限公司 | A kind of paddy-field flattening degree detection system |
| CN109900193A (en) * | 2019-04-02 | 2019-06-18 | 嘉兴古辛达贸易有限公司 | A kind of Detection System for Bridge |
| CN109900193B (en) * | 2019-04-02 | 2020-12-15 | 金华市八咏交通工程检测有限公司 | Bridge detecting system |
| CN113638293A (en) * | 2021-08-11 | 2021-11-12 | 齐爱娴 | Road and bridge strength detection device |
| CN114808689A (en) * | 2022-05-19 | 2022-07-29 | 大连理工大学 | Detection vehicle for extracting modal parameters of bridge |
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