US1728668A - Reproducer of phonographs - Google Patents

Description

Sept. 17, 1929. c. H. DAVIS REPRODUCER OF PHONOGRAPHS Filed March 25, 1927 Patented Sept. 17, 1929 PATENT OFFICE CLAUDE HUDSON DAVIS, OF MOSMAN, NEW SOUTH VIALES, AUSTRALIA, ASSIGNOR TO THE RESONATOR LIMITED, 013 SYDNEY, NEW SOUTH WALES, A COMPANY OF NEW" SOUTH WALES REPRODUGER OF PHONOGBAPHS Application filed March 23, 1927, Serial No. 177,702, and in Australia December 29, 1926.

The invention relates to a type ofphonograph reproducers in which sound vibrations are imparted to a comparatively large ring preferably of cane by a needle which is clamped in a holder upon the ring and follows the sound groove of a disc record in the ordinary manner. The ring has secured within it the larger end of a conical amplifier made of thin material. I have found that to connect the amplifier to the ring by gluing or other similar means is detrimental to the quality of. tone and the principal object of the present invention is the connection of the amplifier to the ring by such means and in such way that good quality and volume of tone result.

According hereto the ring has a groove upon its inner circumference and the end of the amplifier is wedged therein by cords of twisted strands of cotton, silk or similar fibre.

There is also provided a bracket for con neoting the ends of the material from which the ring is produced, and which bracket als( forms one of the elements in apparatus for supporting the re-producer while in use.

In the accompanying drawings Figure 1 is a front elevation;

Fig. 2 is an enlarged vertical cross sectional view through the frame and amplifier.

Figure 3 a side elevation.

Figure 4 is an enlarged vertical sectional detail showing the bracket, spindle head, spindle and pillar when assembled.

Figure 5 is a perspective view of the connecting bracket.

The ring 1, preferably of cane or wood, but which may be of other material such as vulcanite or celluloid, has a groove 2, which receives the end of a conical amplifier 3 of thin material such as wood veneer. The cords 4 and 5 of twisted silk are wedged and glued into the groove upon the inside and outside of the amplifier, the edge of which preferably should not contact with the bottom of the groove.

Cane wedges 6 are used to reinforce the ring and also to assist in the conduct of vibration, at the place where a needle holder'S is located. The needle holder has a binding screw 9 which clamps the needle in a socket in the holder and an integral screw threaded portion which screws into the ring at the angle suitable for the needle.

Referring now more particularly to Figures 3 to 5. A. bracket 11 fits the curve of the ring and is secured thereto by the bolts 12 and 13. When the ring is not continuous but produced by bending a rod the bracket forms a medium for connecting the ends.

The ears 14 pass through slots in the bracket and each has a curved extension 15 which fits a recess 16 in the bracket and is firmly held therein between the bracket and the ring.

The ears project through the bracket and are hinged in the head 17 of a supporting spindle 18, turnable freely in a vertical hole in the pillar 19. The underside of the head contacts with the top of the pillar. A pivot pin 20 passes through holes in the ears and through corresponding holes in the head, thereby permitting free movement of the reproducer in a vertical are.

A wood screw 21 is employed to secure the pillar to the phonograph machine. It is deemed preferable to use the cord wedges upon both the inside and outside of the amplifier. but if desired the cord may be used only upon one side its place upon the opposite side being supplied by wedge resembling the wedges 6 spaced at intervals around the rlng.

T claim:-

1. An acoustic device wherein is combined a ring having a groove on its inner circumference. an amplifier the outer periphery whereof is located in the groove, fibre cord wedging the amplifier within the groove, and a needle holder secured to and connected solely to said ring.

2. An acoustic device including in combination a ring having a groove on its inner circumference, an amplifier the outer periphery whereof is located in the groove, fibre cord wedging the amplifier within the groove, a needle holder secured to and connected solely to the ring and wedging means of substantially rigid material located in the groove adjacent where said needle holder is located.

3. An acoustic device ineludin; in combination a ring having a more on its inner circinnferem'e, an amplifier the outer periphery whereof is located in the groove. means for wedgin;- the aniplitier within the groove and a needle holder set-tired to and connected solely to said rin Tl. An acoustic device including in combination a ring having a groove on its inner CllCllIllftl'tIHLt, an amplifier the outer periphery whereof is located in the groove, means for wedging the amplifier within the groove. a needle holder secured to and connected solely to said ring. a bracket connected to said ring, a spindle. means for pii'otally mounting said hracket on said spindle, and a pillar having a .hole therein extending sill)- stantially vertically thereof which receives said spindle.

In testimony whereof, I ha \e this 25th day of February A. D. 1927 :i; ned my name to this specification.

CLAUDE HUDSON DAVIS.

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