US1480786A - Phonograph reproducer - Google Patents

Description

.Fam'l 1924 c. E. SEMPLE, JR

PHONOGRAPH REPRODUCER im. 15, 1924. y 1,480,7s

C. E. SEMPLE, JR

PHONOGRAPH REPRODUCER Filed May 24, 1922 3 sheets-sheet 2 aEAem/le, c?,

MTA/5555."

Jan, 15, 1924. 1,480,786

c. E. SEMPLE, JR

PHONOGRAPH REPRODUGER Filed May 24. 1.922 SIShee'LS-Sheeb 5 IIIA.

A lunI l y gnu-Mdo? aemjale, 1,7 1-.3

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Patented .lam 15, 1924.

CHARLES E. SEMPLE, J R.

, 0F YOUNGSTOWN, OHIO.

PHONDGRAPH REPRODUC'ER.

Application filed May 24,

To all whom it may concern.'

Be it known that l, CHARLES E. SEMPLE, J r., citizen of the United States, residing at Youngstown, in the county of Mahoning and State of Ohio, have invented certain new and useful Improvements in Phonograph Reproducers, of which the following is a specification.

This invention relates to reproducers for phonotgraphs andthe like, and has particuar re erence to a novel stylus bar construction and mounting, and instrumentalities associated therewith, for effecting an improved operating relation between the stylus ar and the diaphragm as well as an improved operation of the diaphragm itself.

A primary object of the invention is to provide a novel stylus bar mounting which is extremely sensitive, avoiding to a great extent foreign sounds, blasts and the like, thereby greatly enhancing the character of the reproduction. In this connection the invention proposes a stylus bar co-ordinated with the diaphragm in such a manner as to hold these two elements in tension relation without subjecting the diaphragm to undue strain, or impeding or hindering the free action of the stylus bar and connecting parts in their movements. That is to say, it is proposed to provide a. construction wherein the stylus bar and diaphragm are held in unitary relation and in balanced tension, thereby avoiding looseness of parts, aswell as avoiding undue strain upon the diaphragm.

Another object of the invention is to provide a novel diaphragm control means. This is accomplished throu h suitable sub-diaphragms or washers an pads, which are re tained in proper position in contact with the diaphragm by means of the balanced stylus bar and diaphragm ipstrumentalities above mentioned. L

With the above and other objects in view which will more readily appear as the na- -ture of the invention is better understood,

the same consists in the novel construction, combination and arrangement of parts, hereinafter more fully described, illustrated and claimed.

A preferred and practical embodiment of the invention is shown in the accompanying drawings, in Which- Figure l is a plan view of a reproducer illustrating the present improvements.

Figure 2-is a cross sectional view.

1922. Serial No. 563,442.

Figure 3 is an enlarged detail elevation of the stylus bar and balancing bar.

Figure 4 is a horizontal sectional view taken on the line 4 4. of Figure 3 showing the balancing bar and the link which engages with tlie diaphragm.

Figure 5 is a detail view of the connection between the stylus bar and the link.

Figure 6 is a detail perspective view of the stylus bar.

Figure7 is a detail view-illustrating a combined form of balancing bar and tensioning coupling.

Figure 8 is a detail View of a further modified form of balancing bar and tensioning coupling.

Figures 9 and l0 are detail views taken at right angles to each other illustrating a modified bearing for the balancing bar on the diaphragm.

Figure l1 is an enlarged detail View 0f a modified arrangement for connecting the link with the diaphragm. v

Figure l2 is an enlarged detail sectional view taken at right angles to Figure ll.

Similar reference characters .designate corresponding parts throughout the several figures of the drawings.

Heretofore it has been the usual practice to utilize a stylus bar made of either a hard material such as steel or asofter metal. If made of a soft material, with sufiicient stiliness to convey the sound vibrations to the diaphragm without loss, it must be quite heavy and therefore correspondingly slow in action, usually causing blasting. Also since action and reaction are equal and in opposite directions, the stylus bar assumes the character of a small hammer beating on the record, and, obviously, the heavier the hammer the faster thel record is destroyed.

When using a stylus bar of hard material,

and attempting to make it lightl and at the same time suiliciently strong. some method of stii'ening must be resorted to, such as tempering in the case of steel, or in the case 0f other` materials, the choice must be a material that is naturally stiff. A hard stylus bar of this character is very vibrantand easily sets up vsympathetic vibrations giving off sounds peculiar to the material, which are magnified by the diaphragm and reproduced along with the musical composition thereby making an unnatural or lforeign sound, which is, of course, not desirable.

In carrying the present invention into.

effect, I propose to use a stylus bar made of comparatively soft material and of special formation in cross-section to add stiffness. In addition to providing a novel stylus bar the invention also contem lates a novel relatively flexible mounting t erefor.

Stylus bar mountings may be classified generally into two types. one of which aims to connect the stylus bar more or less rigidly to the diaphragm, while the other class provides a relatively flexible connection at this point. In the type of mounting wherein the stylus bar is relatively rigidly connected to the diaphragm, there is a tendency to distort the diaphragm thereby setting up therein undesirable partials and causing additional sounds, which are not on the record, to be created on the diaphragm and imposed on the composition being reproduced. Furthermore, stylus mountings of this character are comparatively stiff in action and tend to prevent the needle from properly responding to the sound waves recorded in the record, thereby giving the reproduction a thin and unnatural tone, as well as causing blasting when notes of high frequency or great amplitude are encountered.

The flexible type of connection between the arm and the diaphragm has heretofore been generally used upon reproducers ,for playing' records of the hill and dale, or undulating type. In such reproducers the weight of the parts is distributed in such a manner that the stylus point is maintained in engagement kwith the record while the tail end of the stylus bar, through a connecting link, is kept taut with the diaphragm. Therefore, the'weight of the reproducer is the only means of keeping the loosely hung stylus bar connections and diaphragm in properly engaging relation. In practice it has been found that the weight of the reproducer alone is not sufficient to hold the stylus bar in close operating relation with the diaphragm at all times, nor is it sufficient to hold the stylus bar fulcrum firmly on its bearing under unusual requirements imposed in reproducing tones of high frequency or great amplitude.

Inlorder to overcome the objections incidental to the different types of stylus bar, and the different types of mountings therefor, the present invention contemplates a novel construction and mounting which will connect the stylus bar and diaphragm in unitary relation with each other, while at the same time permitting the necessary freedom of action at all points of oscillation and also without imposing undue strains on the diaphram'due to' the tensioning of the stylus bar. l

Accordingly, by reference to the accompanying drawings it will be Aobserved that the present device includes in its organization a stylus bar A, a balancing bar B yieldingly connected thereto, a' tensioning coupling C, and a connecting element L between the stylus bar A and the diaphragm D. While the details of this organization may be changed to meet manufacturing and other requirements, nevertheless, the general structure resulting from the combination 'and arrangement set forth embodies the novel and distinctive features of the present iuvention.

Referring first to the stylus bar A, it will be observed that the same is preferably of relatively hollow formation, thereby affording not only the advantages of light weight but also tending to avoid undesirable local vibrations which produce foreign sounds. That is to say, the stylus bar is preferably provided with a head 1 for carrying a stylus point while the body 2 is of substantially U-shaped or channel formation, the same being preferably made of a comparatively soft annealed material. Not only does the shape and material of which the bar is made have the effect of deadening cr dampening local vibrations, but also it conveniently permits of coating the interior of the channel with beeswax or the like.

Intermediate its ends, the body 2 of the bar A is provided with the oppositely extending knife-edge bearings 3 for engaging in the troughed seats 4 of the support or bridge 5 Vcarried by the frame F of the reproducer. Also, the underside of this bridge 5 is preferably provided with a knife edge bearing 6 upon which the balancing bar B rests. This knife-edge 6 is directly in line with the seats upon which the knife-edges 3 bear so that both the stylus bar A and thc balancing bar B have their fulcruming points located on a common center line. And,

to assist in holding the balancing bar B in position, that is to prevent undue shifting or accidental displacement, the said bridge I5 is. provided `at one side of the knifeedge 6 with a pin 7 which projects through a flared opening 8 inthe balancing bar B, as clearly shown in Figures 2 andl 3 of the drawings. The object of providing the flaring opening 8 is to further reduce friction and for the same reason the said pinv 7 is offset to one side of the knife edge. As

will be observed from Figure 4 the end 9 of the balancing bar B may be made in the form of a loop adapted to bear `upon the diaphragm D, as will hereinafter more fully appear, while the opposite \end 10 is connected by the tensioning coupling member C with the head of the stylus bar A.

' `This tensioning coupling member C con-` stitutes one of the novel features of the invention` and is preferably made in the form of a spring loop or eye, formed of fiat spring steel, one leg o of wh'ch engages the end 10 of the balancing bar B While the other leg c2 connects with the hook 11 at the head 1 of the stylus bar A. When the tensioning coupling member C is thus engaged,ithas a tendency to draw the head 1 of the/stylus i bar and the end of the balancing bar B toward each other, thereby forcing the opposite or tail ends of these members. This relatively opposite movement of the tail ends of these members co-ordinate to equalize the tension exerted upon the diaphragm D through the link L. That is to say, the tendency of the stylus-bar A to move in one direction is communicated to the diaphragm D through the link L, While the tendency of end 9 of the balancing bar B to move in the opposite direction causes it to bear against the central part of the diaphragm, as clearly shown in Figures 1, 2 and 4 of the drawings.

The link Ii for connecting the stylus bar with the diaphragm preferably consists of a shank portion 13 having a loop or eye 14 at one end thereof for receiving the T-head 15 formed at the tail end of the stylus bar A, and, as will be observed from Figure 5. the said loop or eye is preferably of elongated formation to permit of the said T-head being inserted therein and then rotated 90 so that the end of the link yand the end of the stylus bar may be readily and quickly interlocked. This novel type of interlock prevents possibility of accidental disengagement and yet at the same time allows the main stylus and link to be perfectly free to perform their intended functions. To fury ther reduce friction at the point of connection. the edge of the eye or loop 14 which contacts with the stylus bar is preferably formed with a knife edge 16.

The opposite end of the shank 13 of the link L is preferably fo-rmed with an enlarged head or button 17 which has a relatively swiveling engagement with a hard washer 18 at the inside Aof the diaphragm D. Also, to prevent the setting up of local vibrations in the link L, the shank portion 13 thereof may be fitted with a tubular covering 19.

Obviously, any suitable and practical form of diaphragm D may be used in connection with the present stylus bar mounting connection, but one preferred type that is particularly adapted for coordination with the novel instriunentalities herein described is shown in the drawings, and, for the purpose of fully explaining the functioning and operation of the invention, reference will now be made thereto. In the embodiment shown in Figure 2. the diaphragm structure D preferably consists of a main diaphragm plate 20 having a cork ring 21 secured to the face thereof. while within the said ring 21 is arranged a ring 22 of felt or the like upon which rests a bearing or stitfening member in the form of washer 23 preferably of the same material as the diaphragm 20. On top of this sub-washer a pad 24 may be placed as a cushion bearing for the end'ofl the effect of the action of the Stylus bar in transmitting the vibration to the diaphragm.

By reason of the comparatively large central area covered by the absorbing and stabilizing members, together with the rigid formation of the diaphragm platel 20, the tendency of the diaphragm to vibrate in partials and causing sounds arising therefrom, which are foreign to the recorded sound, is materially reduced. In other words, the arrangement shown causes the diaphragm to move more as a whole than in partials.

`When using diaphragms other `than the form shown in Figure 2, it should be pointed out that washers 18, 18a, 22 and 23 may necessarily require changes in their size and form in order to better overcome the aforementioned tendency of the diaphragm to vibrate in parta-ls.

From the foregoing it will be apparent that the primary novel and distinctive features of the. invention are a stylus bar and a balancing bar yieldingly connected thereto, which. together with the connecting elements, exert pressure on the opposite side of the diaphragm, thereby maintaining the stylus connections as well as the diaphragm in tension, avoiding looseness, providing a very sensitive constructlon and rehevmg the diaphragm of distorting tension or stress,

and also at the same time permitting the use of padding means, as for example pads 18@l and 22. or padded Washers or bearing members 18 and 23, in combination for controlling or modifying the tendency of the diaphragm to vibrate in partials.

In the above connection it may be noted that the present invention not only contemplates the coordinating of the stylus and the diaphragm, as hereinbefore illustrated and described, but also contemplates combining with the main diaphragm suitable bearing members 18 and 23 for example, in such manner as the conditions may require. In Figure 2, as well as in Figures 7 to 10 inclusive, it will be observed that the so-called bearing members 18 and 23, which may take substantially the form of Washers of the same material as the diaphragm\ 20, are spaced from the diaphragm by means of the felt pads or washers 18a and 22. It is pointed out that the felt pads are not adhesively secured to the diaphragm, but loosely bear thereon so that they will not flex or bend the handling of the reproducer, the outer face of the bridge or support 5 is provided with a guard G which overlies and protects these elements as at G and G2 in Figure 1.

To provide the necessary clearance for the stylus point carried by the head 1 of the stylus bar A, the body of the guard has an opening G3, while the lateral extensions G2 permit of the guardbeing attached to the bridge by means of screws or equivalent fasteners. r l

`By way of illustrating the range of modification which may be resorted to in carrying the invention into effect, reference may be made to Figures 7 to 12 inclusive of the drawings, which show several practical details of modifications.

Referring first to Figure`7, it will be observed that the stylus bar A may be used in connection with a combined balancing bar and tensioning coupling B2. In this embodiment the bar B2 is preferably made of resilient metal, the body portion B3 of which is formed in substantially the same manner as the balancing bar B, as heretofore described,

while the end opposite the one bearing against the diaphragm is formed into a spring loop portion B4. Thus, the balancing bar and tensioning means may be an integral member according to this embodiment of the invention.

A further modification is shown in Figure 8 wherein the stylus bar A is used in conjunction with a bar B5 the end B6 of which bears against the diaphragm in the manner already described, while the end B'l connects with a straight tensioning coupling C3. The tensnioning coupling C3 may be of an elastic or yielding material in event that the balancing bar Bi is made of more or less rigid material; or, on the other hand, if the bar B5 is made of resilient material, it may be placed under tension by using a straight piece of wire orthe like for the coupling C3. In the latter event the inelastic coupling C2 would, of course, be relativel short so as to maintain the yielding or exible bar B5 .relatively bowed and under tension at all times.

Figures 9 and 10 of the drawings illustrate a modified form of bearing for the balancing bar B on the diaphragm. As previously indicated, a'certain amount of longitudinal movement of the balancing bar B may take place, and in the construction shown in Figures 1 and 2 that is provided by the soft pad 24. However, if it is desired to further reduc-e friction at this point a knife edge bearing member 26 may be used. This member may consist of the knife edge portions 27 connected by a web 28, and respectively bearing against the underside of the bar B and the upper side of the hard washer fw. By this arrangement, friction at this point is reduced and at the same time provision made for the longitudinal movement of the bar B.

y To further assist in clarifying the tone by increasing the sensitiveness of the connection between the 'link and the diaphragm at the inner side of the latter, the construction shown in Figures 11 and 12 may be utilized. As will be observed from the figures referred to, the link L may be provided with a loop L" at its upper end for receiving a knife edge member L8 adapted to bear against the hard washer to2 which rests upon the pad 18", or the like. .This construction provides for a limited area of contact between the link and the diaphragm and makes this type of connection very sensitive. However, in using this form of connection it is necessaryA to provide means for preventing an air leak at this point, and to that end a small conical cap 29 is glued or otherwise secured to the washer 102.

It will, of course, be understood that other modifications may be adopted in carrying the invention into effect, but the foregoing is to illustrate certainv of the most practical modifications which have been found efiicient in practice. f Y

Without further description it is thought that the features and advantages of the invention will be readily apparent to those skilled in the art and it will, of course, be understood that changes in the form, proportion and minor details of construction .v may be resorted to within the -scope of the appended claims.

I claim:

1. A sound reproducer including a diaphragm, a stylus bar operatively connected with' the diaphragm, and a second bar having a tensioning connection with the stylus bar and engaging with the diaphragm and normally neutralizing .the tens1on imposed on the diaphragm by the stylus bar.

'2. A sound reproducer ofthe class described, lincluding a diaphragm, -a stylus bar, a balancing bar.I means for connecting said diaphragm to said stylus bar, and means for connecting said diaphragm and said stylus bar with said balancing bar in such a manner as to hold said diaphragm and saidstylus bar in tensioned relation, substantially as described.

, stylus bar and the balancing bar are drawn toward each other to place the same under tension.

4. A sound reproducer of the class described including a diaphragm, a stylus bar connected with the diaphragm, and means for imparting opposing tensioning forces to the diaphragm and stylus bar.

5. A sound reproducer of the class described including a diaphragm, a stylus bar flexibly connected with the diaphragm, and means engaging with the diaphragm and with the stylus bar for placing the two under tension and relieving the diaphragm from -undue strain.

6. A sound reproducer of the class described including a diaphragm, a stylus bar flexibly connected with the diaphragm, and a balancing bar connected with the stylus bar and also bearing on the diaphragm adjacent the point where the4 stylus bar connects therewith.

7. A sound' reproducer of the class described including a diaphragm, a. stylus bar flexibly connected with the diaphragm, and a balancing bar yieldingly connected with the stylus bar and bearing against the diaphragm adjacent the point where the stylus bar connects therewith.

8. A Isound reproducer of the class described including a diaphragm, a stylus bar flexibly connected with the diaphragm, and a balancing bar, one end of which is yieldingly connected to the stylus bar while the oppositevend bears against the diaphragm adjacent the point where the stylus bar connects therewith.

9. A sound reproducer of the class described including a diaphragm, a stylus bar fulcrumed intermediate its ends, means for flexibly connecting the bar and the diaphragm, and a balancing bar fulcrumed in line with the stylus bar and having one end bearing against the diaphragm, and an elastic connection between the balancing bar and the stylus bar.

10. A sound reproducer of the class described, including a diaphragm, a support arranged at one side of the diaphragm, a stylus bar fulcrumed in said support, a connection between the stylus bar and the diaphragm, a balancing bar also fulcrumed on said support and having one end bearing against the diaphragm and a tensioning coupling connecting the opposite end of the balancing bar with the stylus bar.

11. A sound reproducer of the class described, including a diaphragm, a support arranged at one side of the diaphragm and having a. knife edge, a stylus bar having knife-edge bearings resting on said support, a connection between one end of the stylus bar and the diaphragm, a balancing bar fulcrumed on the knife edge of the support and having one end bearing against` the diaphragm. and a tensioning coupling member connecting the other end of the balancing bar with the stylus bar.

12. A sound reproducer of the class described, including a diaphragm, stylus and balancing bars fulcrumed intermediate their ends and having' a tensioning connection at one end, a link for connecting the stylus bar with the diaphragm, and a knife edge device interposed between the end of the balancing bar and the diaphragm.

13. A sound reproducer of the class described, including a diaphragm, a stylus bar having a substantially T-shaped end portion, a link having an elongated eye for receiving the T-head portion of the stylus bar and interlocking therewith.

14. A sound reproducer of the class described, including a diaphragm, a stylus bar having a substantially T-shaped end portion, and a link having a relatively elongated eye, one side of which is provided with a knife edge, said-eye being adapted to receive the T-head of the stylus bar whereby when the T-head is turned 90 it will be interlocked with the eye and the knife edge of the latter will bear on the shank of the said T-head.

15. A sound reproducer of the class described, including a diaphragm, bearing members at opposite sides of the diaphragm, a stylus bar flexibly connected indirectly with the diaphragm through one of said bearing members, and a balancing bar yieldingly connected with the stylus bar and bearing indirectly against the opposite face of the diaphragm through the other of said bearing members.

16. A sound reproducer of the class described, including a diaphragm, padded washers at opposite sides of the diaphragm, a stylus bar flexibly connected indirectly with the diaphragm through one of the padded washers, and a balancing bar yieldingly connected with the stylus bar and bearing indirectly against the opposite face 'of the diaphragm through the other of said padded washe '17. A sound reproducer of the class described including a diaphragm, a pair of padded washers having Atheir padded sides in contact withopposite faces of the diaphragm, a support arranged at one side of the diaphragm, a stylus bar fulcrumed 1n said support, a connection between the stylus bar and one of said padded washers, a balancing bar also fulcrumed on said support and having one end bearing against the other washer and a tensioning coupling connecting the opposite endsl of the balancing bar and the stylus bar.

18. A sound reproducer of the class described including a diaphragm, a pair of padded washers having their padded faces disposed on opposite faces of said diaphragm and in contact therewith, a stylus bar, a balancing bar, a tensioning means, means for connecting one of said washers to said stylus bar, means for connecting the other washer with said balancing bar, the tensioning means being so disposed between the stylus bar and the balancing bar as to hold said diaphragm 'firmly clamped between said padded washers substantially as described.

-19. A sound reproducer of the class described including a diaphragm, pads loosely mounted thereon, a tensioned balancing construction including tensioned members one of which isa stylus bar exerting opposing forces on opposite sides of the diaphragm and serving to clamp said pads to the diaphragm.

20. A sound reproducer of the class described including a diaphragm, a pair of padded washers having their padded sides iii-contact with opposite faces of the diaphragm, a support arranged at one side of the diaphragm, a stylus bar fulcrumed in said su port, a connection between the stylus bar ang one of said padded washers, a `balancing bar also fulcrumed on said support and having a knife edge bearing device interposed between one end of said balancing bar and the other washer and a tensioning coupling connecting the opposite ends of the balancing barand the stylus bar.

21. A sound reproducer of the class described including a main diaphragm, a stylus bar having tensioning connections exerting opposing forces against opposite sides of the diaphragm, and bearingmembers in ,contact with the opposite faces of the main diaphragm and held in position thereon by means of said tensioned connections.

In testimony whereof I hereunto afiix my signature in the presence of two witnesses.

CHARLES E. SEMPLE, JR.

Witnesses:

LnrLA C. AUGUSTIN-E, NABEL SczEmNcK.

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