Summary of the invention
The objective of the invention is to design a kind of measurement mechanism of small momentum, come the measurement space micro-thruster, as the momentum of PPT generation.
A kind of small momentum measurement mechanism of small momentum measurement mechanism of the present invention comprises quiet, central shaft, moving frame, electromagnetic force correcting mechanism, counterweight, displacement transducer; Wherein, central shaft is installed on quiet, is socketed with moving frame on the central shaft, on the moving frame electromagnetic force correcting mechanism and counterweight are installed, displacement transducer also is installed.
Described quiet comprises base, adjustment circle pin, trimmer, support A, support B, upper junction plate, moving frame bearing, electric wire installation plate.Base is a levelling bench, and the upper surface of base and following trimmer be installed respectively symmetrically and adjust fillet is adjusted between fillet and trimmer and is connected by screw flight; Base upper surface dual-side place is equipped with support A, support B respectively, and another side edge of base upper surface is installed with moving frame bearing; Support A is fixedlyed connected by upper junction plate with support B upper end, makes the relative fixed of support A and support B upper end; The upper junction plate top is equipped with the electric wire installation plate.
Described central shaft comprises chassis, first pivot, first split ring, first ring set, the first pivot anchor clamps, main shaft, second split ring, second ring set, second pivot, the second pivot anchor clamps and last dish, pad.
Have center pit on the chassis, the first pivot lower end is provided with pad by locating mutually between center pit and chassis between the chassis and the first pivot lower end; Be socketed with first ring set and first split ring on first pivot from the bottom to top successively, by first split ring and first ring set with first pivot and chassis relative fixed; The main shaft bottom has center pit, and locate mutually by center pit and main shaft first pivot upper end, is provided with pad between main shaft and first pivot upper end.And first pivot is clamped by the hard-wired first pivot anchor clamps in main shaft bottom, make first pivot and main shaft relative fixed; The main shaft upper end has center pit, and locate mutually by center pit and main shaft the second pivot lower end, is provided with pad between second pivot and the main shaft; Be with second ring set and second split ring on second pivot from top to bottom successively, second pivot is fixed in main shaft by second split ring and second ring set; There is center pit last dish lower end, and locate mutually by center pit and last dish second pivot upper end; Last dish bottom is fixed with the second pivot anchor clamps, by the second pivot anchor clamps second pivot upper end is clamped, and makes second pivot and last dish relative fixed; Intermediate shaft is installed between quiet middle base upper surface center and the web joint.
Described moving frame is a long slab, and on the fixedly sleeved main shaft in central shaft, the minor face central point of moving frame is positioned on the axis of main shaft, moving frame with quiet in move on the frame bearing and fixedly connected; One end of moving frame is settled electromagnetic force correcting mechanism and counterweight, electromagnetic force correcting mechanism and counterweight.
Small momentum thruster to be measured is placed on moving frame one end, and during pulsed plasma thruster work, the small momentum of generation can make moving frame swing, and obtains the displacement signal of moving frame swing by displacement transducer, thereby obtains the maximum position of moving frame swing.The yaw displacement of the moving frame that obtains according to electromagnetic calibration mechanism and the relation of electromagnetic force, and the cycle of the moving frame swing that measures finally obtain the momentum that small momentum thruster to be measured produces.
The invention has the advantages that:
(1) moving frame rotates around central shaft and does not have friction;
(2) the electromagnetic force correcting mechanism is contactless, and has uniform and stable internal magnetic field;
(3) installation of thruster is simple and convenient, and the required power lead of thruster is arranged and brought influence to eliminate;
(4) ratio of damping of electromagnetic damping circuit generation can be regulated according to measurement requirement.
Description of drawings
Fig. 1 is the small momentum measurement mechanism of a present invention structural representation;
Fig. 2 is quiet shelf structure synoptic diagram in the small momentum measurement mechanism of the present invention;
Fig. 3 is center spindle structure synoptic diagram in the small momentum measurement mechanism of the present invention;
Fig. 4 is electromagnetic force correcting mechanism structural representation in the small momentum measurement mechanism of the present invention;
Fig. 5 is a permanent magnet mechanism explosive view in the electromagnetic force calibration structure.
Among the figure:
Quiet 2-central shaft of 1-3-moves frame 4-electromagnetic force correcting mechanism
5-counterweight 6-displacement transducer 101-base 102-adjusts the circle pin
103-trimmer 104-support A 105-support B 106-upper junction plate
The moving frame fixed bar of the moving frame bearing 108-electric wire installation plate 109-brace table 110-of 107-
The 201-chassis 202-first pivot 203-first split ring 204-first ring set
The 205-first pivot anchor clamps 206-main shaft 207-second split ring 208-second ring set
The 209-second pivot 210-second pivot anchor clamps 211-goes up dish 212-pad
301-moves frame fixed orifice 401-permanent magnet mechanism 402-coil 403-small magnet group A
The 404-small magnet group B 405-enameled wire 4011-left side magnet 4012-first wide coupling ring
The magnet 4015-second wide coupling ring 4016-second narrow coupling ring among the 4013-first narrow coupling ring 4014-
The right magnet 4018-of 4017-small magnet
Embodiment
Below in conjunction with accompanying drawing the specific embodiment of the present invention is described in further details.
As shown in Figure 1, small momentum measurement mechanism of the present invention comprise quiet 1, central shaft 2, moving frame 3, electromagnetic force correcting mechanism 4, counterweight 5, displacement transducer 6.Wherein, quiet 1 is used for supporting whole small momentum device, central shaft 2 is installed on quiet 1, is socketed with moving frame 3 on the central shaft 2, and an end of moving frame 3 is equipped with electromagnetic force correcting mechanism 4 and counterweight 5, on the moving frame displacement transducer 6 is installed also.
Described quiet 1 comprises base 101, adjustment circle pin 102, trimmer 103, support A104, support B105, upper junction plate 106, moving frame bearing 107, electric wire installation plate 108, brace table 109, as shown in Figure 2.Base 101 is the horizontal rectangular platform, and the upper surface of base 101 and place, following four angles are provided with trimmer 103 respectively and adjust fillet 102, adjust fillet 102 and are connected by screw flight with 103 of trimmers.By regulating the relative position between trimmer 103 and the adjusting circle pin 102, realize the horizontality of small momentum proving installation is adjusted.The design of base 101 upper surface centers has heavy stand and through hole, is used for locating and mounting center axle 2.Base 101 upper surface dual-side places are equipped with support A104, support B105 respectively, and another side edge of base 101 upper surfaces is installed with moving frame bearing 107.Support A104 is fixedlyed connected by upper junction plate 106 with support B105 upper end, makes the relative fixed of support A104 and support B 105 upper ends.Described moving frame bearing 107 is " L " shape, and the end face of " L " minor face is fixedlyed connected with base 101, is installed with moving frame fixed bar 110 on " L " long limit.Be fixed with down the brace table 109 of " U " shape structure at the upper junction plate upper surface, be used for installing electric wire installation plate 108 on the brace table 109.Electric wire installation plate 108 is used for arranging circuit, as: the power lead of the thruster of small momentum to be measured.For the influence minimum of circuit that makes layout to measuring, need be with circuit away from the miscellaneous part in the measurement mechanism, therefore electric wire installation plate 108 is designed to the long slab structure, vertically be installed in brace table 109 tops, fixedly connected with brace table 109 tops in the lower end of electric wire installation plate 108, the upper end is used for arranging circuit.By the above-mentioned general frame that has been connected to form small momentum measurement mechanism.
Described central shaft 2 is the friction free elastic shaft, as shown in Figure 3, comprise chassis 201, first pivot 202, first split ring 203, first ring set 204, the first pivot anchor clamps 205, main shaft 206, second split ring 207, second ring set 208, second pivot 209, the second pivot anchor clamps 210 and last dish 211, pad 212.
Wherein, have center pit on the chassis 201, locate mutually by center pit and 201 on chassis first pivot, 202 lower ends, is provided with pad 212 between chassis 201 and first pivot, 202 lower ends.Be socketed with first split ring 203 and first ring set 204 on first pivot 202 from the bottom to top successively, make first pivot and chassis 201 relative fixed by first split ring 203 and first ring set 204, implementation is: first split ring 203 is designed to the truncated cone-shaped ring texture, and upwards there is an opening in week; First ring set, 204 central through hole edges are recessed structures; First ring set 204 is fixedlyed connected with chassis 201 by bolt, cooperate with the frustum cone structure of first split ring 203 by the recess on first ring set 204, make recess push first split ring 203, make the two ends of the opening part that makes progress in 203 weeks of first split ring close, first split ring 203 clamps first pivot 202, makes first pivot 202 and chassis 201 relative fixed thus.
Main shaft 206 bottoms have center pit, and locate mutually by center pit and main shaft 206 first pivot, 202 upper ends, are provided with pad between main shaft 206 and first pivot, 202 upper ends.And pass through the hard-wired first pivot anchor clamps 205 in main shaft 206 bottoms with 202 clampings of first pivot, make first pivot 202 and main shaft 206 relative fixed.
Main shaft 206 upper ends have center pit, and locate mutually by center pit and main shaft 206 second pivot, 209 lower ends, is provided with pad between second pivot 209 and the main shaft 206.Be with second ring set 208 on second pivot 209 from top to bottom successively and second split ring, 207, the second pivots 209 are fixed in main shaft 206 by second split ring 207 and second ring set 208.Wherein, second split ring 207 is identical with first split ring, 203 structures, and second ring set 208 is identical with first ring set, 204 structures; Second ring set 208 is fixedlyed connected with main shaft 206 by bolt, cooperate with the frustum cone structure of second split ring 207 by the recess on second ring set 208, make recess push second split ring 207, make the opening part two ends that make progress in 207 weeks of second split ring close, second split ring 207 clamps second pivot 209, makes second pivot 209 and main shaft 206 relative fixed thus.
There is center pit last dish 211 lower ends, and locate mutually by center pit and last dish 211 second pivot, 209 upper ends.Last dish 211 bottoms are fixed with the second pivot anchor clamps 210, by the second pivot anchor clamps 210 second pivot, 209 upper ends are clamped, and make second pivot 209 and last dish 211 relative fixed thus.By the connection between above-mentioned parts, finally form intermediate shaft 2, and intermediate shaft 2 structures are flexible, can freely adjust the position between each parts.Intermediate shaft 2 is installed in quiet 1 between the base 101 and upper junction plate 106, and wherein chassis 201 is embedded in the heavy stand of base 101 upper surfaces in quiet 1, and is connected by the through hole of bolt and base 101 upper surfaces.Last dish 211 is fixedlyed connected with upper junction plate 106 by bolt; On upper junction plate 106, have through hole in the present embodiment, the second pivot anchor clamps 210 place through hole, last dish 211 is positioned at the web joint top and fixedlys connected with web joint, thereby the relative positioning of dish 211 and 106 of upper junction plates in the realization, and upper junction plate 106 also can be played a supporting role to central shaft 2, on coil " U " shape opening that 211 upper end is positioned at brace table 109.
Described moving frame 3 is a long slab, is socketed on the main shaft 206 in the central shaft 2, as shown in Figure 1 by screw retention.The minor face central point of moving frame 3 is positioned on the axis of main shaft 206, has moving frame fixed orifice 301 on the moving frame 3, and moving frame fixed orifice 301 is threaded with moving frame fixed bar 110 on the moving frame bearing 107 in quiet 1, realizes moving the location of frame 3.One end of moving frame 3 is settled electromagnetic force correcting mechanism 4 and counterweight 5, and electromagnetic force correcting mechanism 4 is 400mm with the axis normal distance of counterweight 5 distance center axles 2; The other end of moving frame 3 can be settled the thruster of small momentum to be measured, and as pulsed plasma thruster, the axis normal of small momentum thruster distance center axle 2 to be measured distance is 500mm; Counterweight 5 is used for the weight of the thruster of balance small momentum to be measured, makes the center of gravity of moving frame 3 be positioned on the axis of central shaft 2.Also have on the moving frame 3 and be used for the cable hole of cabling.
Described electromagnetic force correcting mechanism 4 for being contactless correcting mechanism, is used for calibrating small momentum, and calibration is not subjected to the influence of frame 3 swings.As shown in Figure 4, electromagnetic force correcting mechanism 4 comprises permanent magnet mechanism 401 and coil 402, and permanent magnet mechanism 401 comprises left magnet 4011, first wide coupling ring 4012, the first narrow coupling ring 4013, middle magnet 4014, second wide coupling ring 4015, the second narrow coupling ring 4016, right magnet 4017.
Wherein, the first narrow coupling ring 4013 is identical with second narrow coupling ring 4016 structures, is the annulus of internal diameter 44mm, external diameter 60mm, length 2mm; The first wide coupling ring 4012 is identical with second wide coupling ring 4015 structures, be internal diameter 40mm, external diameter 50mm, the annulus of length 12mm, the right-hand member of the first wide coupling ring 4012 and the first narrow coupling ring 4013 are connected, and the left end of the second wide coupling ring 4015 and the second narrow coupling ring 4016 are connected; Magnet 4014 during magnetic is connected with between the left side of the right side of the first narrow coupling ring 4013 and the second narrow coupling ring 4016, middle magnet 4014 has axial magnetic field, and an end that links to each other with the first narrow coupling ring 4013 is the N utmost point, and an end that links to each other with the second narrow coupling ring 4016 is the S utmost point; The week of the first wide coupling ring 4012 and the second wide coupling ring 4015 upwards respectively magnetic be connected with left magnet 4011 and right magnet 4017, left magnet 4011 and right magnet 4017 have magnetic field radially, and left magnet 4011 radial outer ends are the N utmost point, the inner is the S utmost point; Right magnet 4017 radial outer ends are the S utmost point, and the inner is the N utmost point;
Magnet 4014 is made of 6 small magnet group A4018 in described, and each small magnet group A403 is formed by stacking by 4 small magnets 4018; Every small magnet 4018 has axial direction of magnetization; 6 even magnetic of small magnet group A4018 is connected circumferential position between the end face of the end face of the first narrow coupling ring 4013 and the second narrow coupling ring 4016; Described left magnet 4011 respectively is made of 12 small magnet group B404 with right magnet 4017, and evenly magnetic is connected on the first wide coupling ring 4012 and the second wide coupling ring 4015 circumferential lateral walls respectively, and each small magnet group B404 is formed by stacking by 3 small magnets 4018; Described small magnet 4018 is the neodymium iron boron small magnet of 10mm * 6mm * 2mm, and the internal diameter circle of the limit of 10mm and the first narrow coupling ring 4013 and the second narrow abutment ring 4016 is tangent among the small magnet group A403;
Described coil 402 as shown in Figure 4, be wound with enameled wire 405 on the coil rack, the end face diameter of coil rack is less than the internal diameter of permanent magnet mechanism 401, and coil 402 enters into permanent magnet mechanism 401 internal diameters, make electric current and permanent magnet mechanism 401 internal magnetic field actings in conjunction on the coil 402, produce calibrated force.
Produce the known and controlled electromagnetic force of size by electromagnetic calibration mechanism 4, this electromagnetic force is used as the calibrated force of standard.Under the effect of this power, moving frame 3 can deflect, thereby sets up the yaw displacement of moving frame 3 and the relation between the electromagnetic force.
Small momentum thruster to be measured is placed on moving frame 3 one ends, during pulsed plasma thruster work, the small momentum that produces can make moving frame 3 swing, and obtains the displacement signal of moving frame 3 swings by displacement transducer 6, thereby obtains the maximum position of moving frame 3 swings.The yaw displacement of the moving frame 3 that obtains according to electromagnetic calibration mechanism 4 and the relation of electromagnetic force, and the cycle of moving frame 3 swings that measure finally obtain the momentum that small momentum thruster to be measured produces.