RU97100156A - COMPENSATION ACCELEROMETER - Google Patents

Claims (1)

1. A compensation accelerometer comprising a detachable housing, a sensing element placed thereon on an elastic suspension, current leads from the housing to the sensing element, a gas damper connected electrically in series and forming a compensation loop, an angle differential sensor, a preamplifier, a corrective circuit, an output stage, made by a power amplifier circuit, and a differential torque sensor with sources of constant magnetic fluxes and moving coils, and the blade is a sensitive element The entente, the elastic suspension and the mounting frame are made of a single plate of the sensing element, which is a silicon single crystal plate, and the moment sensor coils are mounted on the blades of the sensing element through adapter washers, characterized in that each half of the detachable housing is made in the form of a bar with a cylindrical hole made of silicon single crystal of the same orientation as the plate of the sensing element placed in a cylindrical hole with a gap of a cup-shaped magnetic circuit made of magnetic meshes material with a central rod, consisting of a permanent magnet with axial polarization and a pole piece of soft magnetic material, and mechanically connecting the bar and the magnetic circuit of the connecting part - temperature compensator, each adapter washer is made of silicon single crystal of the same orientation as the plate of the sensing element, and the sensor angle consists of two differentially included toroidal coils, each of which is mounted on the central core of its magnetic circuit, and an alternator ysokochastotnogo signal electrically connected to the input of the power amplifier and the control input of a demodulator included in the compensation circuit between the preamplifier and correcting circuit, wherein the split housing accelerometer is mounted within an outer protective housing.  2. The accelerometer according to claim 1, characterized in that the elastic suspension is made in the form of four elastic beams located in one plane, neutral with respect to the outer surfaces of the silicon wafer of the sensor, symmetrically with respect to the axis of suspension of the sensor and symmetrically with respect to the axis of the pendulum of the sensor, the ends of the pair of beams located on one side of the axis of the pendulum, located behind the suspension axis from the sensor, are fixed one in the mounting frame, the other in the senses to the elements, and fastening of beams in the pair, located on the other side of the pendulum axis symmetrically specified.  3. The accelerometer according to claim 2, characterized in that the two beams of the elastic suspension symmetrical about the axis of the pendulum are located in the first plane parallel to the neutral plane of the silicon wafer of the sensing element and offset relative to the neutral plane, the other two beams of the elastic suspension are also symmetrical about the axis the pendulum are located in a second plane parallel to the neutral plane of the silicon wafer and symmetrical with respect to the first plane.  4. The accelerometer according to claim 3, characterized in that the ends of all the beams of the elastic suspension located behind the axis of the suspension from the sensing element are fixed in the mounting frame.  5. The accelerometer according to claims 1 to 4, characterized in that the current leads are made in the form of electrically conductive strips deposited on the beams of an elastic suspension.  6. The accelerometer according to claims 1 to 5, characterized in that the cylindrical wall of each bowl-shaped magnetic circuit is a permanent magnet with axial polarization, and the central core of the magnetic circuit is made of soft magnetic material.  7. The accelerometer according to claims 1 to 5, characterized in that the central core of each magnetic circuit is made of soft magnetic material, and the sources of constant magnetic flux are made in the form of two toroidal coils, each of which is mounted on the central core of its magnetic circuit and is electrically connected to a current stabilizer .  8. The accelerometer according to claims 1 to 7, characterized in that the central rods of the cup-shaped magnetic circuits have through coaxial central cylindrical holes, while a rod of magnetically soft material is placed in each central hole with the possibility of adjusting the position.  9. The accelerometer according to claim 8, characterized in that the adapter washers of the torque sensor coils have through-hole central cylindrical holes coaxial with the holes in the central rods of the magnetic cores, the diameters of all the central holes in the central rods and adapter washers are the same, the blade of the sensing element has a through rectangular hole , the smallest size of which is greater than or equal to the diameter of the holes in the central rods and adapter washers, while a three-stage c an cylindrical rod made of non-magnetic material having diameters of the extreme steps equal to the diameter of the central holes in the central rods of the magnetic cores, the diameter of the middle stage smaller than the diameter of the central holes in the adapter washers, and the length of the middle stage is greater than the minimum distance between the pole pieces of the central rods of the magnetic cores.  10. The accelerometer according to claim 9, characterized in that the total length of the three-stage rod is less than the distance between the outer ends of the cup-shaped magnetic circuits, and the rod itself is made of soft magnetic material.  11. The accelerometer of claim 10, characterized in that the three-stage rod is made of non-magnetic material, and in the free sections of the holes from the three-stage rod in the central rods of the magnetic cores are placed with the possibility of adjusting the position of the rods of soft magnetic material.  12. The accelerometer according to paragraphs. 1 to 11, characterized in that an additional toroidal adjustment coil of the angle sensor, consisting of several sections, is fixed on the central shaft of each magnetic circuit, and some sections of each coil are short-circuited.  13. The accelerometer according to claims 1 to 12, characterized in that the temperature compensator in each half of the detachable housing is made in the form of a cylindrical sleeve located in the gap between the silicon bar and the magnetic circuit, coaxial to the cup-shaped magnetic circuit and having a length approximately equal to the height of the cup-shaped magnetic circuit, the portion of the sleeve facing the sensing element is mounted on the magnetic circuit, the opposite portion of the sleeve is mounted on a silicon bar, and the temperature compensator is made of material with a temperature coefficient expansion coefficient approximately equal to the coefficient of expansion of silicon. 14. The accelerometer according to item 13, wherein the first temperature compensator in one of the halves of the detachable housing is made of a material with a temperature coefficient of expansion α _t1 satisfying the dependence
α _t1 -α _cr = 2k _t / (K _do • l _o ),
where α _kr is the temperature coefficient of expansion of silicon;
k _t is the coefficient of temperature drift of the zero signal of the angle sensor;
K _do - the gear ratio of the angle sensor;
l ₀ is the length of the temperature compensator at the temperature setting of the angle sensor. 15. The accelerometer according to 14, characterized in that the second temperature compensator in the second of the halves of the detachable housing is made of material with a temperature coefficient of expansion α _t2 , satisfying the dependence
(α _T2 -α _kr) ± (α _m1 -α _kr) = 2k _t / (K _dy • l _o).
16. The accelerometer according to item 13, wherein the first temperature compensator in one of the halves of the detachable housing is made of material with a temperature coefficient of expansion α _t1 , satisfying the dependence
α _t1 -α _cr = 2K _dm • k _I / (C • l _o ) • (C • K $\genfrac{}{}{0ex}{}{\text{-1}}{\text{do}}$ • K $\genfrac{}{}{0ex}{}{\text{-1}}{\text{mustache}}$ • K $\genfrac{}{}{0ex}{}{\text{-1}}{\text{dm}}$ +1)
where k _I is the coefficient of temperature drift of the zero signal of the accelerometer;
K _dm - coefficient of transmission of the torque sensor;
C is the stiffness of the elastic suspension of the sensing element;
K _us - the gear ratio of the series-connected pre-amplifier, correction circuit and power amplifier. 17. The accelerometer according to clause 16, characterized in that the second temperature compensator in the second of the halves of the detachable housing is made of material with a temperature coefficient of expansion α _t2 , satisfying the dependence

18. The accelerometer according to item 13, wherein the portion of the sleeve of the thermal compensator facing the sensing element is mounted on a silicon bar, the opposite section of the sleeve is fixed to the magnetic circuit, and the thermal compensator is made of material with a temperature coefficient of expansion approximately equal to the temperature coefficient of expansion of the material of the cylindrical the walls of the cup-shaped magnetic circuit. 19. The accelerometer according to p. 18, characterized in that the first temperature compensator in one of the halves of the detachable housing is made of material with a temperature coefficient of expansion α _t1 , satisfying the dependence
α _t1 -α _m = 2k _t / (K _do • l _o ),
where α _m is the temperature coefficient of expansion of the material of the cylindrical wall of the bowl-shaped magnetic circuit. 20. The accelerometer according to claim 19, characterized in that the second temperature compensator in the second of the halves of the detachable housing is made of a material with a temperature coefficient of expansion α _t2 satisfying the dependence
(α _t2 -α _m ) ± (α _t1 -α _m ) = 2k _t / (K _do • l _o ).
21. The accelerometer according to p. 18, characterized in that the first temperature compensator in one of the halves of the detachable housing is made of material with a temperature coefficient of expansion α _t1 , satisfying the dependence
α _t1 -α _m = 2K _dm • k _I / (C • l _o ) • (C • K $\genfrac{}{}{0ex}{}{\text{-1}}{\text{do}}$ • K $\genfrac{}{}{0ex}{}{\text{-1}}{\text{dm}}$ +1).
22. The accelerometer according to item 21, wherein the second temperature compensator in the second of the halves of the detachable housing is made of material with a temperature coefficient of expansion α _t2 satisfying the dependence

23. The accelerometer according to paragraphs. 13 - 22, characterized in that the cylindrical sleeve of the temperature compensator has several end-to-end through the thickness of the sleeve and directed along the forming slots on each end side, the length of which is approximately half the length of the sleeve, the number of slots on each side of the sleeve is the same, and the slots on one end side of the sleeve are along the cylindrical surface of the sleeve in the spaces between the slots on the other end side of the sleeve.  24. Accelerometer PP. 13 - 22, characterized in that the cylindrical sleeve of the temperature compensator has on each end side several pairs of slots through the thickness of the sleeve, located in planes perpendicular to the axis of the sleeve, the number of pairs of slots on each end side of the sleeve is the same, the pairs of slots on each side of the sleeve are symmetrical relative to the plane perpendicular to the axis of the sleeve and passing through its middle, and the mounting points of the sleeve of the temperature compensator to the magnetic circuit and silicon bar are on a cylindrical surface x bushings between the slots of each pair.  25. The accelerometer according to paragraphs. 1 - 24, characterized in that the output stage of the amplifier of the accelerometer compensation loop is made in the form of a pulse modulator, a current generator and a switching circuit, while the input of the pulse modulator is connected to the output of the correction circuit, the control outputs of the pulse modulator are connected to the control inputs of the switching circuit, and the output the current generator is connected to the coils of the torque sensor through a switching circuit, and, in addition, in the channel of the accelerometer compensation loop, the output of the pre-amplifier is connected to the input of the projected onto circuit through a switch and a storage capacitor, wherein the control key input connected to the control output of the pulse modulator. 26. The accelerometer according to claims 13 and 18, characterized in that on the cylindrical surface of each of the temperature compensators in its middle part a strain gage is mounted with a sensitivity axis parallel to the measuring axis of the accelerometer, while both strain gages are connected differentially to each other, and the output of the differential circuit of the strain gages is connected with the output of the power amplifier of the output stage of the accelerometer compensation loop through an additional amplifier with a gain K _d equal to

where m • l is the pendulum of the sensitive element of the accelerometer;
S is the cross-sectional area of the sleeve of the temperature compensator;
m ₁ is the mass of the cup-shaped magnetic circuit and half of the sleeve of the thermal compensator;
K _Tr - the coefficient of transmission of the strain gauge;
K _ds - transmission coefficient of the differential circuit of the inclusion of strain gages.  27. The accelerometer according to claims 1 to 26, characterized in that the adapter washers for fastening the coils of the torque sensor to the blades of the sensing element are made of a material with a temperature coefficient of expansion greater than the temperature coefficient of expansion of the plate of the sensor and less than the temperature coefficient of expansion of the material coils.  28. The accelerometer according to claims 1 to 26, characterized in that the adapter washers mounting the coils of the torque sensor to the blades of the sensing element are made in the form of several mounting pads of the same height, formed from the base material of the sensitive element in the manufacture of the base.