SU1347020A1 - Movable system of moving-iron instrument - Google Patents

Abstract

The invention relates to a measuring technique and can be used in the production of electroelectric electrical measuring instruments with the fastening of a moving system on the bridge. The movable magnetoelectric interface system has a frame 1 with a working winding 2 and an arrow pointer 3 installed in the working gap 4 of the magnetic system in the form of a magnet 5 and the intraframe core 6, suspended on extensions 7. The internal ends of the extensions 7 are fixed on frame 1 by means of axle boxes 10 and plates 11. Each axle 10 is loosely inserted into the hole 12 of the U-shaped bracket 14. A fixing layer 15 is applied on the plate 11, for example, VK-32-200 glue. The size of the hole 12 is chosen from the ratio of o .. (. E "01x) where RO. the radius of the hole 12; RO, E is the radius of the opening of the axle 10; b - Maximum allowable value of the transverse deviation of the instrument frame; maximum transverse eccentricity value. The invention improves the dynamic characteristics of mobile 3 sludge. from sl 13, ro 4 fig. /

Description

The invention relates to a measuring technique and can be used in the mass production of electroelectric electrical measuring instruments with the fastening of a moving system on stretching.

The purpose of the invention is to improve the dynamic characteristics of the mobile system.

Fig, 1 schematically shows the proposed mobile system, front view and top; Fig. 2 is a design diagram for explaining the balancing process; in FIG. 3, the sequence of positions of the base system in the process of its balancing.

The movable system of the electrical measuring device of the magnetoelectric system contains a frame 1 with a working winding 2 and an arrow pointer 3 mounted on it, placed in the working gap -4 of the magnetic system formed by the magnet 5 and the intraframe core 6, and suspended on the extensions 7 fixed by the outer ends to the damping springs 8 that are mounted with the possibility of displacement in the cage 9 The inner ends of the stretch 7 are fixed on the frame 1 by means of non-working sides of the frame installed on the outside. 1 boxes 10, on the ends of which are perpendicular to the axis — plates 11 are fastened, and each box is freely inserted into a hole 12 of a larger diameter, made in the upper part fixed on frame 1 with the help of clips 13 of the U-shaped bracket 14 so that 11 is located between the bracket 14 of the frame Ij and on the side of the plate 11 facing the bracket 14 a fixing layer 15 is applied (for example, VK-32-200 glue).

The automatic balancing of the proposed mobile system is carried out as follows.

Pre-applied to the side of the plate 11 facing the bracket 14, the fixing layer 15.

In the general case, the projection of the center of mass of the moving system C on the plane perpendicular to its axis does not coincide with the center of rigidity Op lying on the axis of rotation of the moving system,. those. on the line passing through the attachment points of the struts to the frame, by the magnitude of the vector of transverse eccentricity

e, and e, e are the projections of the vector on the transverse axes. Excite forced oscillations.

The moving system around its axis of rotation is fed to the working winding 2 of an alternating electric signal, the frequency f of which is chosen equal to the resonant frequency of the oscillations of the moving system relative to this axis. When a variable electric signal is supplied to the working sides of the frame 1, a variable torque acts on the moving system (FIG. 2), i.e.

a half-period of the moment M acts, for example, counterclockwise (solid line) S and the other half of the period, the moment M acts clockwise (dotted line),

Such an effect of the moment leads to the appearance of torsional oscillations of the mobile system with a resonant frequency f. If the mobile system is statically balanced, its oscillations occur relative to its geometric center, which is simultaneously the center of its rigidity. However, due to the presence of transverse unbalance of the mobile

system occurs relative to its center of mass C, since the moment forming a pair of forces, for example, M, is applied to the working sides of the frame symmetrically with respect to its geometrical

Who is the center of Oh, and the shoulders of these forces, i.e. their distances to the center of mass C are different, of course, for equilibrium, one of the forces of the pair acting on the smaller arm (force F,) must be

more than the other force F acting. on a larger shoulder. Thus, with the torsional action of a pair of forces M in half the period, due to the imbalance, a simultaneous

reinforcement: none, attached to the frame in the reverse direction of the river, directed in the direction of the greater php F, and equal to F, p F –F, (in Fig „2 directed from us). This phenomenon is back to that

when acting on the frame of translational disturbances due to its unbalance, torsional oscillations arise around the axis of rotation.

In the second half of the period at

In the case of a pair of forces acting in the opposite direction of Mj, a resultant transverse 8 appears in a similar way. force F2p Fj - F, directed in figs 2 at the cASC Forces F, p and F ,, are simultaneously with the torsional and transverse oscillations of the frame 1, at which its displacements occur relative to the boxes 10 at the points of their contact, viscous fixing layer 15. At the same time, if the pulling boxes 10 due to their tension with the tension 7 and pressed against the frame 1 at the point of contact with the brackets 14, there is a restoring force that returns them to their original position, the oscillations of the frame 1 relative to the boxes 10 only forces of semi-liquid friction that arise place pressing the staples 14 of frame 1 to the plates 11, where the retaining layer is laminated, 15, due to a force pressing the contact surfaces of the stretching tension rods 7,

If the forces F and acting in the transverse direction are equal, they cause only transverse oscillations of frame 1 with respect to the line of fastening of boxes 10 to frame 1, and the constant component at such vibrations is zero. However, since the transverse oscillations occur along with the torsional, with the location of the center of mass C, as shown in Fig. 2, the transverse force F, acting, as was indicated, simultaneously with the moment Mj, has an effect on frame 1 at larger projections of eccentricity e than the force F, (when rotated clockwise from the initial position, the vector e is closer to the X axis than when twisting counterclockwise).

The occurrence of transverse forces F, and FI is due precisely to the presence of a projection of eccentricity on the X axis (these forces act on the moving system along the Y axis). Thus, for the entire oscillation period, frame 1 is acted on by a constant component, directed in the transverse direction and equal to Fp - F, p. This component causes a constant displacement of the frame 1 relative to the installation locations of the buX 10 in the direction of the Y axis in the direction of decreasing the projection of the eccentricity e ". Frame 1 is shifted until its center of mass C reaches the X axis, i.e. until it becomes zero, the force F is compared with the force Fip, i.e. the constant transverse force Fp causing the displacement of the frame 1 along the axis Y becomes zero. So

Thus, the center of rigidity O of the frame is automatically shifted in the direction of the transverse axis Y before alignment with the center of mass C, whose position relative to frame 1 remains unchanged, and only the attachment point of the frame 7 to frame 1 changes, i.e. installation site axle 10 relative to the frame.

The balancing is carried out in the direction of the Y axis; at the same time, a similar process occurs in the X direction, since under the action of Yyl pairs with moments M and M, transverse forces due to the presence of unbalance arise both along the axis Y due to the projection of eccentricity e, and along the x axis because of the 5

0

five

e. The projection of the eccentricity e. Thus, the shift of the frame 1 relative to the axle box 10 occurs simultaneously on two axes, and ultimately their permanent displacement stops only when the center of mass C located on the axle line of the axle assembly coincides About the moving part.

30 The amplitude I of the electrical signal supplied to the working winding and the time t of excitation continuation are chosen from the condition of the necessary displacement of the box 10 relative to the frame. Excitation modes are selected (calculated) as from the condition of obtaining the necessary accuracy of the balancing process, i.e. convergence of the balancing process with a given degree of accuracy, and

40 of the conditions of the maximum resolution of the process, i.e. the occurrence of the balancing process — the beginning of the displacement of the axle boxes relative to the frame at the minimum (maximum tolerance) timings of the eccentricity projections, as well as at the transverse disturbance as small as possible at a given level of excitation transmitted to the frame

50. f t. and.

X 2.,

1BBO: e extra

8B h U e extra

 T

b and h B

- tension stretch tension;

- width and height of the frame;

-induction in the working gap of the device;

adko

(J is the number of turns of the working winding;

and the maximum allowable value of transverse eccentricity; S, is the area of the calsda of the plates; hg and ld - fixing thickness

layer and its kinematic viscosity;

fo is the coefficient of friction of the rest of the surfaces of the plates and the U-shaped bracket.

On fig.Z shows the sequence occupied by the movable part of the provisions in the process of balancing and subsequent adjustment. In Fig. 3a, the base part is shown in the initial position before balancing; in Fig. 36, the position of the movable part after balancing is shown in a front and top view. The stretch 7 with the bush 10, (Fig. 36) remains in the initial position, and the frame 1 is displaced relative to the magnetic system both in the direction of the X axis and the Y axis by e and e, values. In all known types of devices, the magnitude of the working gap in the magnetic system exceeds the maximum possible unbalance, so such a shift is possible. After such a confusion in the process of balancing

the device is kept for a period of time; 5 will make it possible to use the fixing layer 15, which is necessary for hardening. After the fixing material has hardened, it is necessary to shift frame 1 along with extensions 7, i.e. “the whole moving system is already as a whole, in a position in which the frame t is located symmetrically in the magnetic gap . This adjustment is made by displacing the damping springs 8 relative to the non-sliding casing 9 (Fig. 3b).

Thus, the proposed movable system is extremely simple, it completely lacks balancing elements that worsen; all the characteristics of the device The balancing process is extremely simple, does not require any additional devices and is carried out simply by exciting the torsional vibrations of the moving system by applying to its working winding an alternating electric current, for example, from an audio frequency generator. The method of prior production

Lagged movable system and balancing method for special devices of high accuracy, operating in particularly difficult conditions, exp.

Claims (1)

Invention Formula The movable magnetoelectric system of the 45th instrument, containing a frame with a working winding, on both sides of which is coaxial with it is placed stretching from a pinned plate and on the ends of a box, a plate, a pointer pointer, 50 It also has a U-shaped bracket with a hole in order to improve the dynamic characteristics of the system; fak s;, with a sheathing layer, the bush is placed in the hole P-o, a brass bracket fixed on the front side of the frame, the fixing layer is located without a gap between the plate and the paratshitno leading, the convergence time of the process without fixing time (hardening of the fixing layer) does not exceed 5 s. The balancing process has a very high accuracy that can be easily calculated using derived analytical ratios. By slightly increasing the balancing process time5, the indicated method can be used for serial balancing. mobile systems of devices of the highest accuracy classes; Changing the amplitude of the excitation current signal using the design formulas, achieve the required resolution, i.e., the beginning of the balancing process with the smallest imbalances} which are not even detected by known imbalance control methods. Changing the time of the balancing process, one can achieve the necessary accuracy of balancing even at the maximum possible from these encounters in mobile systems of these types of unbalance values. I The proposed mobile system and The method of its balancing will be used in the mass production of high-precision instruments, while ensuring complete automation of the balancing process, its maximum simplicity and minimum labor intensity. it Lagged moving system and balancing method for special devices of increased accuracy, working in especially difficult conditions of an expeller. of Invention Formula The mobile system of a magnetoelectric device, containing a frame with a working winding, on both sides of which is coaxially with it and placed at the ends of the axle box, the plastic, the ginks located in the torx box, the pointer pointer, about l and h to ha, and so that 5 in order to improve the dynamic characteristics of the system, it is equipped with a U-shaped bracket with a hole; fixing layer, the bush is placed in the hole P-o, baznoy bracket attached to the front side of the frame, the fixing layer is located without a gap between the plate and paratshelnoy 7 1347020 side of the U-shaped bracket, the size of the hole in which is chosen from the condition O. SCH - RO. (C) ,, 5 where RO.CK is the radius of the hole U-shaped. staples; eight radius of aperture of axle box; maximum permissible transverse deviation of the instrument frame; maximum transverse eccentricity value. T Thebes. 2 Editor And, Gorna FIG. Compiled by F.Tarnopolska Tehred A. Kravchuk Proofreader A.Zimokosov Order 5116/43 Circulation 729 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 . Production and printing company, Uzhgorod, Projecto st., 4