Small-scale workshops machine center of gravity pick-up unit
Technical field
The utility model relates to small-scale workshops machine testing equipment, the experiment porch that especially a kind of small-scale workshops machine center of gravity detects.
Background technology
Continuous expansion along with farming, woods, booth work machine market aggregate demand, the market demand of small-sized agricultural work vehicle product is more and more obvious, as license number for the reconstructable modular small multifunctional working machine of CN 1303861C, CN 2453654Y positive drive and the miniature single wheel working rig that drives before and after having etc.Center of gravity is the center of the suffered gravity of object, and in numerous engineering fields, centre of gravity place is an exactly determined parameter of needs.Determine the centre of gravity place of small-sized agricultural work vehicle, for the hook propulsive efficiency of the reaction when quickening of the rollover security that solves balance such as vertical and horizontal, working rig, working rig, working rig and carry out problems such as unit motion and force analysis, all be very important.
The center of gravity measurement of existing large-scale agricultural work vehicle, adopt the mode of two fulcrum liftings to measure the defective of existence: synchro control difficulty during two fulcrum lifting, measuring accuracy are low.
The utility model content
For the synchro control difficulty that overcomes existing working rig center of gravity checkout equipment, the deficiency on measuring accuracy ground, the utility model provides a kind of small-scale workshops machine center of gravity pick-up unit that can avoid synchro control, improve measuring accuracy.
The technical scheme that its technical matters that solves the utility model adopts is:
A kind of small-scale workshops machine center of gravity pick-up unit, comprise plant bottom case and weighing unit, first elevating mechanism is installed on described plant bottom case, second elevating mechanism and the 3rd elevating mechanism, described first elevating mechanism, second elevating mechanism and the 3rd elevating mechanism are triangular in shape mutually, described first elevating mechanism, the upper end of second elevating mechanism and the 3rd elevating mechanism and the bottom-hinged of described weighing unit, described first elevating mechanism, second elevating mechanism all is connected with drive unit with the 3rd elevating mechanism, described first elevating mechanism, second elevating mechanism and the 3rd elevating mechanism are provided with LOAD CELLS.
As preferred a kind of scheme: described triangle is an isosceles triangle, described the 3rd elevating mechanism is positioned at the corner position of described isosceles triangle, described drive unit has two, first drive unit connects described the 3rd elevating mechanism, and second drive unit connects first elevating mechanism and second elevating mechanism.
Further, described drive unit is a spiral lift, described elevating mechanism comprises lifting guide pillar and supporting cell guide, described lifting guide pillar can slide up and down to be installed in the supporting cell guide, the elevating lever of described spiral lift is connected with the bottom of described lifting guide pillar, and the upper end of described lifting guide pillar is by the bottom-hinged of ball pivot and described weighing unit.
Or: described drive unit is a hydraulic jack, described elevating mechanism comprises lifting guide pillar and supporting cell guide, described lifting guide pillar can slide up and down to be installed in the supporting cell guide, the elevating lever of described hydraulic jack is connected with the bottom of described lifting guide pillar, and the upper end of described lifting guide pillar is by the bottom-hinged of ball pivot and described weighing unit.
Further, described lifting guide pillar in a tubular form, described LOAD CELLS is installed in the inner chamber of lifting guide pillar, the top of described lifting guide pillar inner chamber is provided with upper holder block, the bottom of described lifting guide pillar inner chamber is provided with lower lock block, the upper end of described upper holder block and described LOAD CELLS, the lower end of described LOAD CELLS is the semisphere convex joint, the top of described lower lock block is provided with the recessed interface of semisphere, the recessed interface of described semisphere cooperates with the protruding interface of described semisphere, the lower end of described LOAD CELLS and the top of described lower lock block are provided with idle motion, on described lower lock block bearing pin is installed, is provided with pin-and-hole in the both sides, bottom of described lifting guide pillar, described bearing pin two ends are sleeved in the pin-and-hole, the described idle motion of movable stroke ratio of bearing pin is big in the described pin-and-hole, and the lower end of described lower lock block is connected with elevating lever.
Technical conceive of the present utility model is: when center of gravity detects, three fulcrums guarantee that sensor is stressed, and platform are in horizontality by the elevating mechanism 10mm that rises synchronously, measurement also calculates platform quality and horizontal direction barycentric coordinates, determines the initial position of testee; The platform inclination certain angle is measured the measured value of single fulcrum afterwards, and calculates the vertical coordinate of center of gravity, finally obtains the three-dimensional coordinate of center of gravity, promptly can get according to the centre-of-gravity motion theorem:
m
c, m
pQuality for object and platform;
x
p, y
pz
pBarycentric coordinates for support platform;
N
1, N
2, N
3Be respectively the measured value of following three LOAD CELLS of horizontality;
N
1', l is the place an order acting force and the arm of force thereof of fulcrum lifting push rod of heeling condition;
Distance between the two fulcrums of L;
L
dSingle fulcrum is to the distance of two fulcrums;
θ support platform pitch angle;
A, b, c are the coordinate figure of reference point in coordinates computed system of measurand;
G is an acceleration of gravity.
Weighing system can be finished following Performance Detection: complete machine weight; Live axle is heavy; Centre of gravity place is determined (X-Y-Z); Quiet roll stability test.
The beneficial effects of the utility model mainly show: 1) adopt single fulcrum lifting to carry out inclination, the shortcoming of synchro control difficulty when solving two fulcrum lifting; 2) integrate quality, the barycentric coordinates of measuring the small-scale workshops machine, and can realize that dynamic data is measured, the automaticity height; 3) be applicable to the such lighter weight of similar small-scale workshops machine, complex-shaped object, measuring accuracy height.
Description of drawings
Fig. 1 is the structural representation of the center of gravity pick-up unit of embodiment 1.
Fig. 2 is the upward view of Fig. 1.
Fig. 3 is the structural representation of the center of gravity pick-up unit of embodiment 2.
Embodiment
Below in conjunction with accompanying drawing the utility model is further described.
Embodiment 1
See figures.1.and.2, a kind of small-scale workshops machine center of gravity pick-up unit, comprise plant bottom case 1 and weighing unit 2, first elevating mechanism is installed on described plant bottom case 1, second elevating mechanism and the 3rd elevating mechanism, described first elevating mechanism, second elevating mechanism and the 3rd elevating mechanism are triangular in shape mutually, described first elevating mechanism, the bottom-hinged of the upper end of second elevating mechanism and the 3rd elevating mechanism and described weighing unit 2, described first elevating mechanism, second elevating mechanism all is connected with drive unit with the 3rd elevating mechanism, described first elevating mechanism, second elevating mechanism and the 3rd elevating mechanism are provided with LOAD CELLS 3.
Described triangle is an isosceles triangle, described the 3rd elevating mechanism is positioned at the corner position of described isosceles triangle, described drive unit has two, and first drive unit connects described the 3rd elevating mechanism, and second drive unit connects first elevating mechanism and second elevating mechanism.
Described drive unit is a spiral lift 4, described elevating mechanism comprises lifting guide pillar 5 and supporting cell guide 6, described lifting guide pillar 5 can slide up and down to be installed in the supporting cell guide 6, the elevating lever of described spiral lift 4 is connected with the bottom of described lifting guide pillar 5, and the upper end of described lifting guide pillar 5 is by the bottom-hinged of ball pivot 7 with described weighing unit 2.
Described lifting guide pillar 5 in a tubular form, described LOAD CELLS 3 is installed in the inner chamber of lifting guide pillar, the top of described lifting guide pillar inner chamber is provided with upper holder block 8, the bottom of described lifting guide pillar inner chamber is provided with lower lock block 9, the upper end of described upper holder block 8 and described LOAD CELLS 3, the lower end of described LOAD CELLS 3 is the semisphere convex joint, the top of described lower lock block is provided with the recessed interface of semisphere, the recessed interface of described semisphere cooperates with the protruding interface of described semisphere, the top of the lower end of described LOAD CELLS 3 and described lower lock block 9 is provided with idle motion, bearing pin 10 is installed on described lower lock block 9, both sides, bottom at described lifting guide pillar 5 are provided with pin-and-hole, described bearing pin 10 two ends are sleeved in the pin-and-hole, and the described idle motion of movable stroke ratio of bearing pin 10 is big in the described pin-and-hole, and the lower end of described lower lock block 9 is connected with elevating lever.
Mainly form with reference to Fig. 1 by spiral lift 4, elevating mechanism and weighing unit 2 etc.Described weighing system is mainly supported by three fulcrums, and the length of fulcrum 1 and fulcrum 2, fulcrum 3 is adjustable; During work, three fulcrums are common earlier rises 10 millimeters, guarantees that sensor is stressed, and weighs up gross mass, calculates the position of center of gravity on the x-y plane simultaneously; Afterwards, fulcrum 3 rises, and determines lifting height by stepper motor, by the variation that fulcrum 3 is weighed, determines the position (all fulcrum can adopt stepper motor driven mode) on the z axle.
The upper end of LOAD CELLS 3 and upper holder block 8 be by being threaded, and its lower end is unsettled but a hemispheric convex joint is housed.The elevating lever of spiral lift and lower lock block 9 are by being threaded, and the upper end of lower lock block 9 has a hemispheric recessed interface, and bearing pin 10 is housed on the lower lock block 9.The lower end of lifting guide pillar has a groove, and the external part of pin just is positioned at the groove place, and during virgin state, pin is positioned at the lower end of groove.Along with the rising of spiral lift, the recessed interface of the semisphere of lower lock block 9 contacts with the hemispheric convex joint of sensor, and LOAD CELLS 3 beginnings are stressed, and this moment, pin also had a segment distance with the upper end of groove.Spiral lift continues to rise, the lifting guide pillar and upper holder block 8 between also begin to rise under the effect of friction force, if friction force is not enough to make the lifting guide pillar to rise, at this moment, the external part of pin can promote the lifting guide pillar and rise, in the whole process, the lifting guide pillar is not subjected to the gravity of testee, only plays the effect of guiding.
The weighing process of present embodiment: spiral lift makes elevating lever move up and down, spiral lift adopts trapezoidal screw pair and rotatablely moving of high precision worm and gear adjutant stepper motor to be converted into moving up and down of the interior elevating lever of spiral lift, trapezoidal screw has AutoLock feature, both having made does not have clamping device can keep load-carrying yet, three fulcrums are by spiral lift and the synchronous segment distance that rises of elevating mechanism, the assurance sensor is stressed, and platform is in horizontality, and can obtain the quality of measured object this moment.
The live axle retry is tested: the touchdown point of working rig (part that contacts with ground) comprises driving wheel and rotary tillage cutter, so-called live axle retry is tested soon, and driving wheel is placed on the center of gravity detection platform, and the rotary tillage cutter is placed on outside the platform, detected weight is live axle tuple certificate during the detection platform horizontality, and these data are relevant with the soil adhesive ability of working rig.
Quiet roll stability test: with complete being placed on the center of gravity detection platform of working rig, an end is fixed with a place of rope and testing table, and leaves one section active length.Along with the inclination of testing table platform, working rig finally can topple, and the platform angle of correspondence can characterize the quiet roll stability of working rig when working rig toppled state.
Embodiment 2
With reference to Fig. 3, the drive unit of present embodiment is a hydraulic jack 11, described elevating mechanism comprises lifting guide pillar 5 and supporting cell guide 6, described lifting guide pillar 5 can slide up and down to be installed in the supporting cell guide 6, the elevating lever of described hydraulic jack 11 is connected with the bottom of described lifting guide pillar 5, and the upper end of described lifting guide pillar 5 is by the bottom-hinged of ball pivot 7 with described weighing unit 2.
Other structures of present embodiment are identical with embodiment 1 with the course of work.