DE1962832C3 - Electromechanical oscillator for an electrical timer - Google Patents

Description

1. in that the center of gravity of the rotational inertia body coincides with the center of rotation,

2. characterized in that the center of gravity is moved on a straight line which is perpendicular to the Y axis of symmetry. ⁵

If the center of gravity coincides with the center of rotation according to method 1, the force of gravity does not exert a restoring force on the vibrator, whereby a positional error can be eliminated. However, it is practically impossible to carry out the method according to FIG. 1, since there is no fixed center of rotation in such a vibrator. The reason for this is explained below with reference to FIGS. 3 will be explained. In this case, a torque acts only on the spring 2, as a result of which the spring 2 is deformed into a circular arc, the radius of curvature of which is R. The ', "axis in Fig. 3 runs parallel to the spring in the rest position, and the V-axis runs at right angles to the K-axis. * = If the displacement of G is at a distance / 1 from the connection point b in the direction of the .V-axis and K-axis 1 -Y or A y , one obtains

I.γ - fl (l-costf) AsinW, (1) - '.

1 1 · = A (COSO-DT (/ - «sinfc»), (2) force-generated torque. Caused Vn. Frequency effects are in their « ^r f ^s jfj" _n right side and on the left side * ' ^e «; j Fig. c are equal to each other, so that they cancel each other out and have no effect on the frequency.The trajectory of the center of gravity is obtained from equations (6) and (7) by the following equation (8> :

(3 Λ - /)
3 </ 2 Λ)

χ-

(8th)

In order for the center of gravity to move in a straight line, the coefficient of .y ² of equation (8) must become zero. This is achieved when

n-A - - (9)

3/1

ft = -
θ '

cos <y = 1 -

sin © = - θ

β ¹ θ ^χ
2! 4!

6!

< ³ >

If one neglects terms above the fourth power of Θ in equations (4) and (5) and introduces equations (3), (4) and (5) into equations (1) and (2), the result is

-C

(6)

(7)

45

Since θ is significantly less than 1, the error resulting from the omission of the above-mentioned higher terms is extremely small. As can be seen from equations (6) and (7), there is no point at which I .ν and. 1 r become zero at the same time.

In the F i g. 4a, 4b and 4c it has been assumed that the length of the spring is infinite and that the trajectory of the center of gravity G is represented by a straight line. In the F i g. 4a and 4b show a case in which the oscillation symmetry axis Y lies in the gravitational direction (which is indicated by the arrows). In this case * <■ no moment is generated by gravity when the center of gravity G moves in a straight line due to the infinite length of the turning radius, and accordingly no frequency change occurs. ^δ :

F i g. 4c shows a case in which the axis of vibration against the direction of gravity by a Angle λ is inclined. The through the through the hard

Equation (9) thus specifies the condition under which a position error is eliminated.

In the practical case, when both a moment and a bending force act on the spring 2, the equation (9) is not completely fulfilled, however the distance A between the connection point h and the center of gravity G becomes one third of the length / of the spring 2 approximated. Practical tests have shown that A is most favorably chosen between -ς and -r-. < To prove the above, the following measurements should be taken. In FIGS. 5 a and 5 b, the rotational inertia body, which consists of the masses 4 and 5 and the arm 3, is connected by means of a pin to the spring 2, which in turn is connected to the plate 6 by means of a further pin or pin. The positional error n, the one shown in FIG. 5 changes depending on its position \ sinusoidal, as shown in FIG. 6a shows. Several sinusoidal curves with different values for parameter A are shown in FIG. 6a. From the relationship between η and n, as shown in FIG. 6a, the condition can be obtained to achieve η = O. According to FIG. 6a occurs in the described case of the vibrator according to FIG. 5 shows a maximum value of η in two positions, an upper and a lower position, whereby it should be assumed that the mass 4 in the upper position is just above the mass 5 and the mass 4 is in the lower position below the mass 5 should be located.

F i g. 6b shows a graph in which the relationship between A and the position error / 1 η = I is shown, in which, as in FIG. Ία h means the distance between the center of gravity G of the body of inertia and the point h of the spring 2. The in the F i g. The values shown in FIGS. 6a and 6b were obtained by measurements on the oscillator shown in FIGS. 5a and 5b, the spring of which had a length of 47.5 mm and which had a frequency of 16.7 Hertz.

From the graphic representation of FIG. 6 b it can be seen that a position error is only eliminated can be achieved if (in the special case) A = 16 mm is reached. Of course they change Slope of the curve and the point at which the position error becomes zero, according to the size of the mass, the length of the arm and the length of the spring. When

Jer the inertia body is rotated with the center line K of the spring 2 in the horizontal axis of rotation, it is necessary that the center of gravity C lies on the center line K of the spring 2 in order to make the position error zero. The above measurement shows that a positional error can be eliminated if the center of gravity of the body of inertia is on the axis of rotational symmetry Λ /, preferably on the center line A 'of the spring 2, and by about a third of the effective length / of the spring from one End b of the spring 2 is arranged away.

In the F i g. 7a and 7b show an embodiment of a normal oscillator for an electrical timer, the oscillator for switching off a signal at point α in FIG. 2 generated moment from an oscillator part 1 on the left, in which the rotational inertia body is connected to the masses 4 and 5 and the arm 3 with the spring 2 at point b . and a right-hand oscillator part Γ, in which the rotational inertia body is connected to the masses 4 and 5 'and the arm 3' with the spring 2 'at point b . The two oscillator parts are attached symmetrically with respect to the Z-axis on the plate 6 and oscillate in the same plane of oscillation

1 sheet of drawings

Claims (2)

With this arrangement, however, the instant Dieh patent claims point the inertia body a curved path, so that the electromechanical oscillator is not position-independent. 1. Electromechanical oscillator for a 5 The present invention is therefore based on the electrical timer with at least one to give an electromechanical oscillator its one end held spring as oscillating with a high Q value for an electrical timer of the element and one of two by one that is completely free of positional errors.
rigid arm connected masses' existing This object is achieved by the inertia body in claim 1, the invention given on a between the masses io. An inventive lying point with the other end of the spring electromechanical oscillator has the advantage of being connected, the spring being in a plane that it is at relatively low frequencies, symmetrically about a line lying in this plane, ie with frequencies from a few tens to a few symmetry lines can oscillate, ti: <by a hundred Hertz, can be operated without it indicating that the support body 15 has a positional error. Due to the achievable (3, 4, 5) with the free end of the spring (2) so low frequency of the oscillator according to the invention is connected that its center of gravity (C) at rest, the means for converting the state of the oscillator on the symmetry line (Af) oscillating movement in a rotary movement, ie that of its connection point (b) with the free transfer to a display device, in the end of the spring at a distance (Λ) to be ao simplified design and deteriorates in the production of between a third and approve of less. In this way, the use of the eral is half the length (/) of the spring (Fig. 2). inventive oscillator to prevent 2. Electromechanical oscillator after location errors and to achieve a high gear claim 1, characterized by two symmetrical accuracy also economically acceptable in clocks, mutually arranged support bodies (3, 4, 5; 35 An expedient and advantageous embodiment 3 ', 4', 5 ') and by a U-shaped bent, in the invention can be found in the dependent claim, its U-bend centrally held spring (2, 2'), in the following the invention is to be closer to hand with their free leg ends each one of the in The embodiment shown in the drawing Y Inertia body will be explained at one between each of these. In the drawing shows
temporary masses (4, 5; 4 ', 5') lying point 30 F i g. 1 is a view of a known U-shaped bond (Fig. 7a, 7b). Oscillator, F i g. 2 and 3 graphic representations to describe the principle according to the invention, F i g. 4a, 4b and 4c graphic representations for 35 description of the effect achieved by the invention, The present invention relates to an electrical Fig. 5a and 5b a plan view and a transverse mechanical oscillator for an electrical time section through a test oscillator for further transmitters with at least one explanation of the principle according to the invention held at its end,
Spring as a vibrating element and one of two 40 Fig. 6a and 6b the results that were measured on the masses according to the invention connected to it by a rigid arm,
standing inertial body, which is attached to a between F i g. 7a and 7b show a plan view and a section the point lying on the ground with the other end by an embodiment of an oscillator which is connected as the spring, the spring being applied in a time base in an electric timer plane symmetrically about a plane lying in this plane.
Line of symmetry can swing. It is known that in a conventional It is already known that e.g. B. a tuning fork U-shaped vibrator as shown in FIG. 1 is shown. with their high Q-value, as far as the accuracy of the pivot points of the masses 1 is concerned, are significantly better than a restlessness with a third of the total length of the springs 2, and that their low Q-value is; on the other hand, the frequency of the vibrator could be changed in accordance with its position in the gravitational field with the unrest operated at a low frequency,
let the position error be equal to zero, which in FIG. 2 shows a graphic representation of different a watch with a tuning fork was previously impossible. The oscillation phases of a vibrator around which this positional error occurs, however, the more the tuning fork arms appear, the more the tuning fork arms have additional elements. 2 form masses 4 and 5 with the mass masses for reducing the oscillation frequency of the large ml and w2, which are loaded with each other by the arm 3 tuning fork. Such a reduction · are connected to a rotational inertia body, the oscillation frequency of which is however desirable, since the center of gravity is at G. With 2 is a leaf spring order of the device for converting the draws, which has the length / has, with one end of the oscillating movement of the tuning fork in a rotary 60 at the point α on the plate 6 and with the movement at a high oscillation frequency difficult arm 3 of the body of inertia of rotation at point h is such. is connected that the center of rotation of the The French patent specification 1 480 8.48 already has an electromechanical oscillator on the oscillation symmetry with the M axis at the input. This inertial body has become known to the type mentioned above, in which the heavy weight is set in vibration by a torque, point of the inertial body in each case with the eye in the case of the one shown in FIG. 2, a positional pivot point of the inertial body can collapse in the gravitational field by two methods. As it turns out, describes when turned off as follows: