US2785248A - Reed damped vibrator arm mechanism - Google Patents

Description

March 12, 1957 F. L. WHITE REED DAMPED VIBRATOR ARM MECHANISM Filed Dec. 22, 1953 ITTOKNEY United States Patent REED DAMPED VIBRATOR ARM MECHANISM Fredrick L. White, Indianapolis, Ind., assignor to P. R. Mallory & Co., Inc., Indianapolis, Ind, a corporation of Delaware Application December 22, 1953, Serial No. 399,689

5 Claims. (Cl. 200-90) This invention relates generally to electrical translating apparatus and has particular reference to such means and methods including translating apparatus for transferring energy between direct and alternating current circuits.

Interrupter devices, more generally known as vibrators, have been extensively used for converting direct current energy into alternating current energy or into direct current energy of a difierent voltage. In the usual form of these vibrators a reed contact bearing arm usually makes contact with a substantially fixed side contact member at a frequency depending upon the operation of the reed member.

Normally because of the natural resilience of one of these members an oscillatory condition known as vibrator chatter" occurs which acts to decrease the efliciency of the vibrator. Further, because of the unrestrained impact, the abutting contact members become eroded quickly so that after a relatively short time these contacts must be replaced. It is apparent that as the frequency of the vibrator increases these conditions become more pronounced and create a definite operating problem.

Moreover, as data on the continual use of vibrators has been collated it has been found that numerous difliculties arise therein when a compliant reed structure is used.

One of these difficulties resides in the fact that there is a natural tendency for harmonic motion to exist between the point of reed attachment and the reed weight. This tendency causes undesired reed arm motions being transferred to the reed arm contacts which results in contact pressure variations and tuning difiiculties unless these motions are accurately tuned so as to be accurately controlled.

Another method to eliminate these effects has been by making the reed essentially non-compliant and putting substantially all of the systems compliance in the reed arms or in the side springs of the vibrator or to distribute it between the reed arms and the side springs. It is also possible to eliminate these effects by using a damping means on the reed arms so as to eliminate oscillations of the reed arms, as described in U. 5. Patent 2,606,259, issued to Clarence Huetten and assigned to applicants assignee.

In the present vibrator invention, however, this problem has been faced and the difficulties resulting therefrom have been substantially overcome with simplified means being provided so as to eliminate several parts from the reed assembly. Thus, in the present invention the reed, itself, is effectively used as a damping means without the necessity of having a damper spring used either on the outside of the reed arms or between the reed arm and the reed. In the latter cases a member near the reed is formed to space the reed arm contact out away from the reed and so to develop a bias between the reed arms and the damper spring.

In the subject invention, moreover, in contradistinction to the structure heretofore, the reed arms are stamped 2,785,248 Patented Mar. 12, 1957 "ice out in an essentially flat manner and lie flat against the reed, itself. Moreover, the reed arms are constructed to be more compliant than the reed. It is apparent, therefore, that several parts necessitated by the former construction and used in the prior reed assembly are eliminated. in the present invention, to provide good reed amplitude the reed arms of the invention which are more compliant than the reed are made of substantially thin material and have relatively compliant fixed side springs used therewith. It has been found after considerable experimentation that this construction has given excellent efficiency and has shown good results. Thus, the improved reed construction of the present invention has provided a vibrator operating with a minimum of parts and which is adapted to overcome the disadvantage set up by harmonic motion established usually between a point of reed arm attachment and the reed weight or armature. It is therefore an object of the present invention toprovide a vibrator using a novel reed construction which is adapted to prevent undesired reed arm harmonic motion from being transferred to the reed arm contacts, thus to avoid variations in contact pressure and inaccurate tuning difficulties.

Still another object of the present invention is to provide a novel interrupter mechanism having means associated with. the reed for eliminating unwanted harmonic motions between a point of reed arm attachment and the reed armature and to provide maximum efiiciency therefor.

Still another object of the present invention is to provide an interrupter mechanism having a novel reed construction obviating the necessity for side arm damper means and whereby the tendency for harmonic motions existing in said reed arm is eliminated with consequent improvement in the operation of the interrupter.

Still another object of the present invention is to pro: vide a novel interrupter mechanism having damped arm characteristics but wherein said characteristics are obtained in the construction of the reed thereof without the necessity of utilizing auxiliary means and components, thus providing a relatively inexpensive construction for the vibrator as adapted to operate at a maximum efiiciency in a manner similar to such damped arm interrupter.

The invention in another of its aspects relates to novel features of the instrumentalities described herein for teaching the principal object of the invention and to the novel principles employed in the instrumentalities whether or not these features and principles may be used in the said object and/or in the said field.

Other objects of the invention and the nature thereof become apparent from the following description considered in connection with the accompanying figures of the drawing wherein like reference characters describe elements of similar function therein and wherein the scope of the invention is determined rather from the dependent claims.

Referring now to the figures of the drawing:

Figure 1 is a front eievational view of the embodiment of the invention showing the constructional arrangement of the separate parts thereof;

Figure 2 is a side elevational view of the vibrator invention shown in Figure l as adapted to show the novel arrangement of the components which provide means for avoiding harmful harmonic frequencies in the reed construction therein;

Figure 3 is a profile view of the reed assembly used in the present invention and as adapted to illustrate the positional arrangement of the arms of the reed as lying fiat against the reed; and

Figures 4A, 4B and 4C are positional illustrations of the reed arm assembly as opposed to the associated fixed afisaacs contacts as adapted to exemplify the operational relationships therebetween and to define the method of obtaining dampening of the reed arms therein.

Generally speaking, the present invention describes novel vibrator means for obviating chatter or fluttering contact make as developed in the relationship between the vibrator reed arm contacts and their associated fixed contacts and which is due to' the harmonic frequencies usually set up within the reed, itself. instead of using auxiliary .vibrator equipment, for example dampiug springs or stops, or using a construction angulating the reed arm while using a damping spring or stop to give the necessary contact bias, the present invention places and assembles the reed arm to the reed in a manner such that the reed, itselfdamps'out the oscillations of the more compliant reed arms.

In the vibrator as now constructed, the reed arms are uuformed and lie flat against the reed for a substantial distance therealong. Thus, as the reed swings away from the particular arm the said arm will not completely follow the reed. It therefore follows that at the extreme deflection of the reed, this arm may be lifted away from the reed to an extent that it will be free to oscillate. However, on the return swing of the reed, contact will be made between the outer end of the arm and the reed with. the result that the oscillations are damped out before make of the contacts on the reed arm with their fixed side contacts.

In the present novel construction, moreover, there are several advantages that accrue from the mechanism here developed. For example, since there are no forms in the reed arms and no angulations in either the reed arms or side springs, there are fewer tolerances which will have an' effect. on the contact spacing prior to adjustment. Thus, the unit requires a minimum of adjustment. In addition, the unit shows a rising frequency characteristic with an increase in input voltage which helps to prevent the saturation of the transformer at high input voltage and helps to maintain the balance of the vibrator during dwell times.

Referring now to the figures of the drawing, there is shown in an embodiment of the present invention a vibrator generally designated by reference numeral 8. Vibrator 8 has a hook shaped fem-magnetic frame denoted by reference character it) and has a dependent narrowed hook portion 11 around which there is provided a centrally circumscribing wire wound driver coil 12 adapted to be current excited froma suitable supply source. The end of the hook portion is constructed as a magnetic pole piece, with the pole piece and dependent hook portion having equal end widths less than the width of the frame from which the latter depends.

A stack generally denoted by reference character 13 is secured to the lower extremity of ferromagnetic frame it as by means of a single stack screw 14 and nut 15 at a substantial distance away from said dependent hook portion. The stack comprises a plurality of spacers 16, 16a, 16b, 160 which may be fabricated of an electrically insulative material. Between spacers 16 and 16a and 16b and 160 there are included side contact arms 18 and 19 substantially fixedly maintained therebetween as by means of the tight'locking afforded by means of stack screw 14 and nut 15. Clamped between spacers 16a and 16b, at its lower extremity, is a main reed and an armature 34? connected to a fiat elliptical shaped top end of the reed 88 as by weld means 39 but which may be integrally formed and connected thereto at its upper end. All of the spacers of the stack are provided with an alignment hole through which the stack screw may extend. Side contacts 18 and 19 carry relatively fixed contacts 24 and 25 respectively at the ends thereof and cooperate with the vibrator contacts 44 and 46 of the reed arms 49 and 4!,

r as will appear presently.

The structure of the vibratory system will be generally understood from Figures 1 and 2. it will be noted that near the junction of neck 26 and main body section 21,

a second stack is provided. Stack 35 clamps vibrator reed arms 4%} and 41. to the main body section 21 of reed 9 as by means of rivets such as 5% and 51. Each of the vibrator reed arms lies flat against the reed of the vibrator and is punched out flat, having a compliant characteristic greater than that of the reed and being fabricated of a thin material.

Further, side springs 18 and 19 having contacts ZS and 2 are also constructed of a material having a relatively compliantcharacten'stic. Thus, the cooperative operation between the reed arms and the side springs, as described below, will provide the damped arm vibrator character= istic in which the reed itself becomes the damping means, without the use of damper springs or other such structure.

Each of the reed arms 40 and 41 having contacts 44- and 46 has a rectangular main section and a tapered head section 61 integrally joined thereto by means of shoulders 62 and 63. The lower face of each reed arm, in the static position, snugly lies against a surface of the main reed section 21 of reed 9, while the upper surface 74 of the reed arm 41 has a contact such as 46 welded thereto and which on the operation of the vibrator reed is cooperatively adapted to mate with its corresponding fixed arm contact such as 25.

The operation of the vibrator is illustrated in Figs. 4A, 4B and 4C. As disclosed, in Fig. 4A, in the static position the reed arms are unformed and lie flat against the reed for a substantial distance therealong dependent upon the compliance characteristics of the reed arms as opposed to essentially non-compliant characteristics of the reed. Upon operation of the vibrator by excitation of the driver coil and as shown in Figs. 4B and 4C, the reed is seen to swing away from arm 41 so that the said arm will not completely follow the reed. It therefore follows that at the extreme deflection of the reed, the arms may be lifted away from the reed by an angle A, or B having such a magnitude that the arm will be free to oscillate. However, on the individual return swings of the reed, contact will be made between the outer end 8% of the arm 4-9, or end 81 of arm 41, and the reed, with the result that the oscillations are damped out before make of the contacts on the reed arm with their associated fixed side contacts. In this manner a damped arm vibrator mechanism is obtained which uses the reed as a damping means and eliminates the need for auxiliary dampening or stop structure heretofore used to obtain the above results.

The novel damped arm vibrator mechanism using the reed as a damping means as described above is intended to be merely illustrative and not exhaustive and the invention is not intended to be restricted thereby but rather the scope is to be determined by the nature of the claims here appended.

What is claimed is:

1. A vibrator comprising in combination, a vibratory reed swingable toward contact engaging positions and having a free end, means for supporting the other end of said reed, a driver coil, a frame for holding said coil having one end connected to and supported by said reed supporting means, said frame further being bent to have a hook-like configuration including a dependent portion, said dependent portion penetrating said coil substantially at the center thereof, said portion having its end con- Si't'lCiGCl as magnetic. pole piece, said support means for said reed and said frame being positioned substantialavsaaas ly below said pole piece, a pair of fixed side arms held in said support means, an armature connected to said reed and cooperating with said pole piece to activate said reed upon excitation of said coil, and vibrator reed arms more compliant than said reed and separate from said vibratory reed included by second support means held flat against said reed for a substantial extent therealong on said second support means in the rest condition and adapted to move therewith, each of said fiat lying reed arms acting with said reed and lying thereagainst for at least the greatest swing of said reed toward a contact engaging position.

2. A vibrator having damped arm characteristics comprising in combination a vibratory reed swingable toward contact engaging positions and having a free end, stasi means for supporting the other end of said reed, a driver coil, a frame for holding said coil having one end connected to and supported by said reed supporting means, said frame further being bent to have a hook-like configuration including a dependent portion, said dependent portion penetrating said coil substantially at the center thereof, said portion having its end constructed as a magnetic pole piece, said support means for said reed and said frame being positioned substantially below said pole piece, and armature connected to the free end of said reed and cooperating with said pole piece to activate said reed upon excitation of said coil, unformed vibrator reed arms placed on opposite sides of said vibratory reed included by second support means held on said reed and adapted to move therewith, each of said arms being more compliant in characteristic than said reed and lying flat thereagainst for a considerable extent in the static condition of said vibrator, each of said flat lying arms acting with said reed and lying thereagainst for at least the greatest swing of said reed toward a contact engaging position.

3. A vibrator comprising in combination, a vibratory reed swingable toward contact engaging positions and having a free end, means for supporting the other end of said vibratory reed, a driver coil, a frame for holding said coil having one end connected to and supported by said reed supporting means, said frame further being bent to have a hook-like configuration including a dependent portion, said dependent portion penetrating said coil substantially at the center thereof, said portion having its end constructed as a magnetic pole piece, said support means for said reed and said frame being positioned substantially below said pole piece, an armature connected to the free end of said reed and cooperating with said pole piece to activate said reed upon excitation of said coil, vibrator reed arms separate from said vibratory reed included by second support means held on said reed and adapted to move therewith, said reed arms lying fiat against said reed for a considerable extent therealong at rest, each of said arms lagging in swing behind said reed on one portion of the vibratory reed cycle while at another portion of the cycle going toward a contact engaging position, each arm lies ilat against said reed and acting thereagainst for at least the greatest swing thereof.

4. A vibrator comprising in combination, a vibratory reed swingable toward contact engaging positions and having a free end, means for supporting the other end of said vibratory reed, a driver coil, a frame for holding said coil having one end connected to and supported by said reed supporting means, said frame further being bent to have a hook-like configuration including a dependent portion, said dependent portion penetrating said coil substantially at the center thereof, said portion having its end constructed as a magnetic pole piece, said support or ns for said reed and said frame being positioned substantially below said pole piece, an armature connected to the free end of said reed and cooperating with said pole piece to activate said reed upon excitation of said coil, vibrator reed arms being more compliant than said reed and separate from said vibratory reed included by second support means held on said reed and adapted to move therewith, said reed arms being unformed and lying fiat against said reed for a considerable extent therealong at rest, each of said arms lagging in swing behind said reed on one portion of the vibratory reed cycle so that at the extreme deflection thereof away from a contact engaging position the reed arm is lifted away from the reed so that it will be free to oscillate and at the other portion of the cycle going toward a contact engaging position each arm lies flat against said reed and acts therewith for at least the greatest swing thereof.

5 A vibrator comprising in combination, a vibratory reed swingable toward contact engaging positions and having a free end, means for supporting the other end of said vibratory reed, a driver coil, a frame for holding said coil having one end connected to and supported by said reed supporting means, said frame further being bent to have a hooklike configuration including a dependent portion, said dependent portion penetrating said coil substantially at the center thereof, said portion having its end constructed as a magnetic pole piece, said support means for said reed and said frame being positioned substantially below said pole piece, fixed side arms also included thereby, an armature integral with the free end of said reed and cooperating with said pole piece to activate said reed upon excitation of said coil, vibrator reed arms separate from said vibratory reed included by second support means held on said reed and adapted to move therewith, said reed arms being unformed and lying flat against said reed for a considerable extent therealong, said arms being more compliant than said reed and lagging in swing behind said reed on one portion of the vibratory reed cycle going away from a contact engaging position so that the extreme deflection thereof the reed arm is lifted away from the reed by a determined angle dependent on the relation of the compliance characteristics of said arm and said reed so that it will be free to oscillate while at the other portion of the cycle going toward a contact engaging position each arm lies flat against said reed and acts therewith for at least the greatest swing thereof.

References Cited in the file of this patent UNITED STATES PATENTS

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