US1374688A - Transmitter - Google Patents

Description

\ F. E. SUMMERS TRANSMITTER. APPLICATION FILED MAY12| 1919- 1,374,688. Pabenwd Apr. 12, 1921.

n is i r ST re s FRANK E. SUMMERS, or MEMPnIsMIssoURn TRANSMITTER.

T 0 all to 710m it may concern Be it known that FRAN E. SUMMERS, a' citizen of the United States of America, re-.

siding at Memphis, in the county of Scotland and State of Missouri, has invented new and useful Improvements in Transmitters', of which the followingtis a specification.

The purpose of the invention is to provide a new and novel form of variable contact for use in transmitters and similar apparatus, whereby most effective variation of the resistance of the transmitter circuit may be had. The improved variable contact element is adapted for connection with other and similar elements, so that a battery of such elements may be connected to and operated by a transmitter diaphragm.

The invention is illustrated and described in a specific embodiment, to which, however, it is not to be restricted. The right is reserved to make such changes or alterations i as the actual reduction to practice may suggest, in so far as such changes or alterations are compatible in spirit with theanneXed claims. 7 Y 1 In the accompanying drawings: Figure 1 is a view in side elevation of the improved'variable contact member showing the same attached to a transmitter diaphragm, a portion only of which is shown.

Fig. 2 1s a section on the line 2 2 ofv Fig. 1.

Fig. 3 is a central verticalsectional view through the variable contact member.

Fig. 4 is a section on the line 44 of Fi 1.

Fig. 5 is a side elevational view showing two variable contactmembers interconnected with the foremost in connection with a diaphragm.

Fig. 6 is a detailed sectional view in which there is shown a modified form of electrode for the variable contact member.

Referring tothe drawings, the invention is shown as comprising an inflexible disk 1 made of insulating material, this disk abutting the side of a cap 2 formed with an external thread to receive the clamping ring 8 which engages the outer periphery of the cap and holds the disk into firm contact therewith. The interior space comprised by the cap and the-disk 1 provides a chamber in which a variableresistance material 4 may be carried. This variable resistance material is preferably carbon granules, but

Specification of Letters Patent. Patented Apr, 12, Application filed May 12, 1919. Serial No. 296,530.

any other material'suitable to the purpose 8 may be employed. l The cap 2 is made'preferably of metal; likewise is the clamping ring 3. Y 'The disk 1 is designed for attachment to a diaphragm such as that shown at 8 in the drawings, and to this end carries a threaded stud 5'formed' with ahead 6 lying against;

the inner face of the disk and carrying nut 7 bearing against the outer face of the latter. The stud is also secured to the diadisk, thus securing the stud firmly to the phragm 8, being passed through the latter bracket 14, this upright member 13 being secured to the cap'2 by means of a screw 15 whichfpasses through the upright an'd'engages in the threaded hole 16 of a plate 17 the latter being attached to the cap2 by" suitable screws. I H

To oppose the pull of thevdiap'hragm 8, a

tension spring 18 is attachedone end to thescrew 15 and the other to a screw 19, the latter being slidably mounted inthe upright leg of the support 14 and rendered adjustable by anut 20, the turning ofwhich obviously serves to regulate the tensionon the spring 18.

An upright 21 is mounted on the horizontal leg of the support 14 between the upright member 13 and the diaphragm '8, and. this upright carries at its upper end an adjusting vscrew 22 and the vertical leg oi the bracket 14 carries an adjusting screw 23 alined with the adjusting screw 22. 1 Each of these screws has connected to it one end of a spring 24, the remaining ends of the ily respond to air vibration setup by the voice. v g In Fig.5 there are shown two of these variable resistance members connected in tandem, this manner of connection comprising the attaching of the stud 5 of one variable resistance member with the plate 16 of the next.

In Fig. 6 there is shown a modified form of electrode. This electrode is formed with a shank portion 25 passing throughthe disk 1 for the reception of a nut 12, the shank carrying a conical head 26 lying against the inner face of the disk-1 and having its conical surface in contact with the carbon granules 4:.

In the operation of the invention the vibration' of the diaphragm 8 as a result of the sound waves set up by the voice causes the disk 1 and with it the cap 2 and the granules contained therein to vibrate, thereby varying the intensity of contact between the granules and the electrodes. This disturbance set up in the carbon granules effects a variation of resistance in the trans 1 in Fig. 5, it is to be noted that the grouping of the transmitter resistance structures in tandem, makes for a more sensitive variation in the transmitter circuit, in that a variation is effected by each resistance element. Therefore the limits between which the variations in resistance may take place is increased.

I The invention having been described, what is claimed as new and useful is:

1. In a transmitter, the combination of a diaphragm, an insulating disk having connection with the diaphragm, a cap attached to the disk, a variable resistance substance carried within the cap, the cap having means for attachment to a second disk, and electrodes carried by the said disk, whereby a plurality of caps and disks may be assembled in tandem with the diaphragm.

2. In a transmitter, the combination with a diaphragm of an inflexible insulating disk,

a stud connecting the disk with the dia-.

phragm, a hollow cap against the open side of which the disk lies, a clamping ring threadingly engaging the cap and bearing against the disk, a granular conducting material carried in the cap between it and the disk, electrodes mounted in the disk and in contact with the granular material, and a resilient support for the cap for the'useful purpose specified.

3. In a transmitter, the combination with diaphragm of an inflexible insulating disk,

a stud connecting the disk with the diaphragm, a hollow cap against the open side of which the disk lies, a clamping ring threadingly engaging the cap and bearing against the disk, a granular conducting material carried in the cap between it and the disk, electrodes mounted in the disk and in contact with the granular material, a resilient support for the cap, and adjustablespring tensloning means for said support for the useful purpose specified.

4. In a transmitter, the combination With a diaphragm, of an inflexible insulating disk, a rigidconnection between the disk and the diaphragm, a hollow cap against the open side of which the disk is disposed, means detachably securing the disk to thecap, a granular conducting material carried in the cap and contacting with the dislnelectrodcs mounted on the disk and in contact with the granular material, and supporting means for the cap and the disk and permitting the same to vibrate bodily with thediaphragm to effect variations in contact between the granular material. and the electrodes.

In testimony whereof he affixes his signature.

FRANK E. SUMMERS.

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