DE2061793A1 - Method for balancing an oscillating system with a balance wheel and a spiral spring - Google Patents

Description

Patent attorneys
Dii.-i.-lng. A. WEDDE
Dipl.-Ing. K. EM PL
Munich 27, Schumannstr. 2

15. -Dec. 1970

File: F 6984

GJtEIIiEH ELECTROHIC A-G *, Langenthal (Switzerland).

Method for balancing a balance wheel and a balance spring having Sciiwingsystems ·

In of serial production of a balance wheel and a coil spring having oscillating sys- tems% vary kanntlich both dae TragÜieitemoment the balance and the angular directional size of the coil spring ranzbereiche within certain Tole ~, which can not be too tight sized economic reasons · In order each existing To adjust the period of oscillation of the balance wheel of the oscillation systems to a given period of oscillation, a rough adjustment and a subsequent painful adjustment are made using millings or drill holes on the balance wheel

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the unrest as well as the angular size of the spiral springs are taken into account. The application of such averages brings it However, this means that the accuracy with which the specified period of oscillation is practically achieved is comparative is limited and is not yet able to meet higher requirements. Procedures have been proposed which allow the respective existing moment of inertia of the balance wheel to be determined however, require additional measures and measurements and appear to be carried out with a view to their application an automatable adjustment of the oscillation period of the oscillation system in question is too complex and too time-consuming »

The present invention thus relates to a method for adjusting a balance wheel and a spiral spring Oscillating system, in which you first determine the period of oscillation T-, the balance wheel. To fix it one of the shortcomings outlined above is the method according to the invention characterized in that afterwards the moment of inertia of the balance wheel is changed by a known amount q-, then the

J ₀ the resulting period of oscillation T _{2 of} the balance wheel is determined,

to and that you can then adjust the moment of inertia of the balance

oo fl

another amount q » changes that is within the Fenler limit

2 2 T ^ - T ~

Hj - ° [' ~ 2 ο is given in

1 P T *

"*** 2 2

Open through the relationship T ^ - T ~

which relationship ϊ_ is a gate-given period of oscillation, to which the oscillation system should be adjusted

The method according to the invention is described below Hand of the drawing explained in more detail in which

Pig x 1 shows a plan view on a not yet equalized g oscillating system having a balance wheel, and a coil spring,

Pig x 2 is a corresponding plan Figure 1 · calibrates on the oscillating system again there, wherein the balance wheel has been provided with milled grooves, the total of a reduction of the moment of inertia of the balance wheel by a precisely known amount (j, yield, and

Pig · 3 one of the Pig. 2 illustrates a corresponding top view of the oscillating system, in which the balance wheel | additionally zxL Pig · 2 was provided with drill holes, which overall result in a further reduction of the moment of inertia of the balance by the amount o ^, so that β afterwards; the oscillation system with the given oscillation period T, oscillates

The balance shaft 10 of the oscillating system, which is only indicated schematically in FIGS . 1 to 3, is provided, as usual, with a balance 11 consisting of the balance rim with arms. these fastenings

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a spiral roller seated on the balance shaft 10 can be done · For the sake of clarity eats meanwhile, the closer attachment of the inner end of the Coil spring 12 is not illustrated and there are also all other parts of the Schwingsy stars, which the torsional vibration take part in balance shaft 10, in which Pig · I to 3 are not reproduced » It is also assumed that the spiral spring 12 has already reached its final length; preferably her outer end already fastened in the spiral block 15 · The both ends of the balance shaft 10 are now rotatably mounted in a holder, for example, while the spiral block 13 is held immovable in the same holder, so that the Carry out torsional oscillations of balance wheel 11 opposite the holder can »This holder is in the drawing for the sake of clarity not illustrated in more detail · In FIGS. 1 to 3, however, the respective position of this holder and thus also the corresponding position of the oscillation system through the The location of the spiral block 13 is identified.

If one assumes a not yet balanced oscillation system according to FIG. 1, and one assumes how this is for the serial production is advantageous that the ganee Adjustment is only to be carried out by removing material from the balance wheel U, the originally existing rotation-

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The moment of inertia of the balance wheel 11 in each pail is sufficient be big. In this context it should be mentioned that below and in accordance with common usage only the moment of inertia is spoken of, where * - but always the Bo-I related to the axis of the balance shaft IQ moment of inertia is meant »

The not yet balanced oscillating system according to Fig. I is first brought into a specified measuring position, in which, for example, is exactly perpendicular to the axis of the balance shaft IQ runs * In this measuring position, the period of oscillation T, the balance 11 is determined · around the non-linear EigenenseksfteTircrer ^

in the determination, also given by T ^ one Oscillation amplitude of balance 11 used »

The next following second
essentially in the unspecified known per se support ⁵ -heitsmcment of the balance wheel 11 by a precisely known Estrag _. -. ς ^ to be reduced »Ba this way on the balance wheel S ^ L but an additional imbalance will not arise-scÄl ^ the total amount q ^ is divided into m each equal sub-amount ^ a ₁ , where m is a whole positive Jgafcl equal to or greater than 2 means »Correspondingly, the balance wheel 11 κι on the hoop were ze & -

Places given and at each of these places

Partial amount
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the noted partial amount is ~ · 9 &. worn down * In the jig »2

Let m * 2 suppose there are two on the hoop of the balance wheel 11 Milling 14 and 15 shown exactly the same dimensions, that are diametrically opposed to each other · Since the. Dimensions and the meuterial condition of the balance. 11 as well as the Dimensions of the two bezels are known 3ind, is by the two millings 14 and 15 the moment of inertia of the balance 11 do an equally known amount q-, reduced

In the next third process step, the oscillation period Tv is determined, which the oscillation system has after the moment of inertia of the balance wheel U has been reduced by the aforementioned amount q, according to FIG. and T _{2 of} the balance wheel 11 are determined under equivalent operating conditions of the oscillating system and in particular with 3e equal oscillation amplitudes of the balance wheel 11 Measure balance shaft 10

Kachaea now the greats T ^, q- ^ and T ^ are known within the meaning of the present invention, prepare all the data required to process the Oscillation system exactly to a suitably specified oscillation period T, match * To this end, this fourth

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^ 061793

Method step the moment of inertia of the balance 11 by one

further amount q _{9 is} reduced, which is determined by the relationship 2 2

«B ^β <1τ * - * ~ —- ^ is given · Here, too, it is useful to 2 2

the total amount q ₂ *** ^a JiTwwftl η of partial amounts ^ ₂₂ , ·. to ^ _2n , for which there is only funding that their sum (q ^ -t- g ₂ 2 ···· * ^ 2n ^ S ^ ^{eicl1 should be} the total amount (J ₂ ) part · * amounts to za. at least. 5 is selected, you have the opportunity to correspondingly different dimensioning of these installments also has an established at the balance imbalance ea eliminate · Nan thus the frost of the balance 11 further η and another zentriseh lying places derarFrra ^^ b ^ n that none of them come to lie at the location of one of the millings 14 or 15 · In Fig. 3 η «3 is assumed to be caaDmen-una _; -ee are on the ring of the balance wheel. 11 three ^ e at 120 degrees vegetate bores 16, 1? and 13, which overall reduce the previously existing moment of inertia of balance 11 by the amount q ₂

With the second reduction in the balance's moment of inertia. 11 by the amount Q ₂ all normally required balancing processes can be ended - even with the inclusion of an unbalance correction - Sa is therefore possible,

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2ÜB1793

for the specified period of oscillation T, even the setpoint the period of oscillation to which the oscillation system is finally to be adjusted

As far as the dimensioning of the first reduction in the moment of inertia of the balance wheel 11 to be made by the amount cu is concerned, this is expediently used as a preliminary adjustment in the sense that afterwards the period of oscillation T ₂ Kur turns out to be a little greater than the specified period of oscillation T ~ second reduction of the balance's moment of inertia by the amount q. ₂ only result in a fine adjustment, as a result of which the accuracy with which the specified period of oscillation T is finally achieved is significantly improved.

In addition, the advantages of the method explained above are mainly to be seen in the fact that, when it is carried out, a very extensive automation is evident Application can come

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Claims (1)

Patent claim A. ii ·) Method for balancing a balance wheel (11) and a Oscillating system having a spiral spring (12), in which the respective oscillation period T-, the balance wheel (11), characterized in that the 'moment of inertia of the balance (11) is then increased by a known amount qu changes, · then the resulting oscillation period Tg the balance (11) is determined, and that the moment of inertia of the balance (11) is then determined by a further amount g- changes, which is within the error limits by the relationship 2 2
2 3
q, p = qT »-5? r is given in what relation T, a specified period of oscillation is to which the oscillation system should be matched *. ^ 2 · Method according to claim, characterized in that a number m are centrically symmetrical to one another located places (14,15) of the balance (11) whose moment of inertia changes by the same partial amount = »ch in the same direction, and that one is centric to one another at a further number η symmetrically located and not with the aforementioned m places 209821/0495 - ίο - (14,15) coinciding places (16,17,18) of the balance (11) change their moment of inertia by possibly different partial amounts g. «-» * ^ 22 »*** ^ ^ie ^ 2n ^, whereby only the sum (q ^ + ^ ₂ +. · "+ Q ^) of these partial amounts should be equal to the total amount q." And the number m is at least 2 and the number η is at least 3 ^A / £ method according to claim, characterized in that that at least the aforementioned oscillation periods «p and 3? 2 of the balance (11) with mutually equivalent operating conditions of the oscillating system and in particular with the same Vibration amplitudes of the balance (11) are determined. L V CL method according to claim, characterized in that that the specified oscillation period T represents the nominal value of the oscillation period on which the oscillation system should be finally compared * GR2INER ELECTRONIC A »G», 209821/0495