US2424963A

US2424963A - Detachable bridge unit crystal mounting

Info

Publication number: US2424963A
Application number: US513139A
Authority: US
Inventors: Bokovoy Samuel Alexander
Original assignee: Standard Telephone and Cables PLC
Current assignee: STC PLC; Federal Telephone and Radio Corp
Priority date: 1943-12-06
Filing date: 1943-12-06
Publication date: 1947-08-05
Anticipated expiration: 1964-08-05
Also published as: ES182127A1; GB584087A

Description

Aug. 5, 1947. s. A. BOKOVOY 2,424,963

DETACHABLE BRIDGE UNIT CRYSTAL MOUNTING Filed Dec. 6, 1943 2 Sheets-Sheet l l 6 I i ATTORNEY Aug. 5, 1947. s. A. BOKOVOY DETACHABLE' BRIDGE UNIT CRYSTAL MOUNTING Filed Dec. 6, 1943 2 Sheets-Sheet 2 R.0 3% m VA mg U M Y j E 1 3 ATTORNEY Patented Aug. 5, 1947 DETACHABLE BRIDGE UNIT CRYSTAL MOUNTING Samuel Alexander Bokovoy, Verona, N. J., assignor to Federal Telephone and Radio Corporation, New York, N. Y., a corporation of Delaware Application December 6, 1943, Serial No. 513,139

11 Claims.

The present invention pertains to frequency determining units of the resonant type and more particularly to holder structures and electrical and supporting assemblies associated therewith for piezoelectric resonators, A special object of the present improvements is to produce an ad vantageous form of holder and separable crystal mounting assembly having a more general application than structures as heretofore employed. It is designed to facilitate change in the ty e of mounting peculiar to the use of crystals var to vibration mode to meet the r n ments of either high or low frequency circuits. These are of such distinctive design and arrange ment as to have heretofore required fully individual and different structural assemblies.

In accordance with my present invention there is provided an insulating holder desirably having externally extended terminal pins and formed with a socket or enlarged opening for the reception and enclosure of separable and interchangeable bridge supports or crystal mountings provided with electrical terminal and supporting connections standardized as to spacing and connecting arrangement and arranged to complete the circuit connections upon assembling by means of oppositely positioned securing screws. The employment of the separable bridge mounting supports for the crystals permits of the convenient full mounting assembly and testing of the resonant unit externally of the holder, the ready substitution or renewal of the unit and the further incorporation with the standard form of holder of bridge mounting assemblies specially designed for the mounting of the crystals of varied sizes and of mounting arrangement varied in type peculiar to the required vibration modes and frequency values. The improved arrangement, in addition, desirably provides for securing of the terminal pins by assembling of the securing screws and the bridge supports may provide for convenient spacing variation of the crystal supporting elements in certain of its mountings.

The features of the invention will be more fully understood by reference to the accompanying drawings wherein like reference characters are applied to the corresponding parts in the several views.

In the drawings:

Fig. 1 is a plan view of a desirable structural embodiment of the invention with a portion of the cover plate broken away to illustrate the separable mounting unit therein.

Fig. 2 is a vertical, sectional view thereof on line 2- -2 of Fig. 1.

Fig. 3 is a detailed sectional view on line 3-3 of Fig. 1.

Fig. 4 is a perspective view showing a different form of separable mounting unit.

Fig. 5 is a plan view similar to Fig. 1 showing the assembly therewith of a separable mounting unit adapted for resilient and center support of the crystal.

Fig. 6 is a horizontal sectional view of the Fig. assembly.

onal view .l. a preferred th features the invention. as shown -.l '"lgs. l to 3 the container or holder of insulating material is shown as a cylindrical body I formed with the enlarged opening or socket 2 of generally circular contour and open at the front face of the holder body. The opening is closed in the customary manner by a face plate 3 secured by screws 4 with an interposed washer.

At opposite sides the body is formed with thickened wall portions recessed to receive the inner ends of the radially disposed terminal pins 6-6, the reduced end portions of which are provided with threaded apertures therethrough for the reception of the terminal and securing screws 'l-I entering apertures 8 in the holder thickened wall portions; the latter as shown being cut away to provide the ledges 9-9 for the support of a separable or bridge mounting member.

.The separable bridge support or mounting unit as shown comprises an insulating bridge or mounting bar [0 formed to support suitably spaced conducting post contacts H for engagement with the crystal electrodes and combined connectors and mounting member supports I2 of a form and spaced to register with the apertures 8 for the securing of the mounting assembly and closing of the circuit by means of the screws 1. In the disclosed structure, the crystal 0, having the usual opposite silver coating electrodes e engaged by resilient contacts l3 integral with or soldered to the posts H, is end supported as adapted for high frequency oscillation. These electrode coatings eas shown each partially cover the margin or electrode face of the crystal and extend from opposite ends of the crystal so that each electrode face has a noncovered area or end marginal surface adjacent one edge portion of the crystal. The arrangement provides for supporting engagement of the crystals by pressure engagement between the resilient contacts I3 and terminal supporting posts H with the respective terminal supports or posts establishing electrical connection with an oppositely positioned electrode. The connector posts I extend through spaced holes in the bridge l5 and have their ends soldered to the intulne'd flange extensions of the connectors l2 which are attached to the mounting bars by means of screws to threaded thereto. The outer end portions E8 of the connectors are formed as integral extended and offset perforated ears to receive the securing screws 5. Accordingly, removal or the screws '5 permits or" the detachment of the bridge member and its associated electrical connectors as an assembled crystal mounting unit thereby facilitating adjusting, testing or replacement under favorable conditions for proper maintenance. As best shown in Fig. 2 the ledge portions t and 9 are formed to lie in separate and relatively widely spaced vertical planes for connection with connector members positioned upon opposite sides of the bridge mounts 5 thereby to readily accommodate diilerent types of mountings.

In Figs. 5, 6 and 7 there is shown an application of the invention with the incorporation of a different type of center contact crystal mounting of the kind customarily employed for low fre quencies and vibration in the thickness mode. As therein disclosed the detachable mounting unit comprises a yoke form of insulator bridge 25 having the central opening 25 within which tl e crystal 0 is positioned. Supporting and electrical contact engagement with the crystal electrodes is effected by axially aligned contact pins slidably fitted to bores in the mounting member 28 and resiliently pressed into engagement with the crystal by engagement with the adjustable spring terminal connection and the fist terminal connection 25. The tension of the spring 25 is adjustable by screw stud 2i threaded to the yoke and passed through the spring end. The end 32 of the connector or terminal 26 is extended and apertured to receive the screw 7 and a cooperating supporting terminal extension is provided by an angular terminal bar 33 aperture-d to receive the opposite connector securing screw l and secured to the bridge member by screw stud 32 in clamping connecting relation to the sp ing 25. The centrally and axially disposed terminal connectors 25 and El as positioned in the upper and lower surfaces or" the bridge mounting thus cooperate with the ledge supporting a rangement of the standardized holder 5. The socket opening of the latter is suitably enlarged relative to many or the crystals and mountings suificiently to accommodate and protectively enclose a condenser or condensers associated with the controlled circuit.

In Fig. 4 there is shown a separable counting of a form to be interchangeable in the holder with the afore-described forms and providing a further known type of low frequency crystal mounting. In this form the terminal supporting connectors are shown at positioned to coact with the screws 7. They are held by screws 38 threaded to the insulated bridge 3-" and are provided with inturned flanges 39 having longitudinal extensions underlying a series of vertical holes ii in the bridge for engagement by and connection to varied positioned metal posts 42 upon which the crystal is supported by resilient wires G l- 45 soldered to the respective electrodes and posts. The connectors and 3? as shown are positioned on the sides of the bridge and are of a form to position the crystal with its flat surfaces parallel to the flat wall of the holder 4 and positioned centrally therein as effected by the other disclosures.

Having described my invention, I claim:

1. A frequency determining unit of the character described having in combination a holder of insulating material formed with an internal socket for the reception of a crystal mounting unit and a separable crystal mounting unit having a support of insulating material provided with combined connector and mounting member supports'secured thereto and spaced for bearing support on the holder and the said holder being provided with electrical terminal elements and securing means positioned to secure the connector supports and to effect electrical connection with the terminal elements.

2. A frequency determining unit of the character described comprising a holder of insulating material formed with an internal socket, a crystal mounting unit comprising a bridge mounting member of insulating material, combined electrical connector and mounting member suppors secured to the mounting member and formed with apertured extensions positioned to overlie sidewall portions of the holder, electrical terminal elements fitted to the holder in alignment with the extension apertures and securing screws fitted to the extension apertures and threaded to the terminal elements for effecting electrical and securing connection therewith.

3. A frequency determining unit of the character described comprising a holder of insulat ing material formed with an internal socket and side wall recesses communicating with the socket and providing ledges in different horizontal planes, a crystal mounting unit comprising a bridge mounting member of insulating material, combined electrical connector and mounting sup ports secured to the mounting member and formed with apertured extensions positioned to overlie the sidewall ledges of the holder, electrical terminal elements fitted to the holder in vertical alignment with the extension apertures and securing screws fitted to the extension apertures and threaded to the terminal elements for effecting electrical and securing connection therewith.

4. A frequency determining unit of the character described comprising a holder of insulating material of substantially cylindrical form having an internal socket and sidewall recesses communicating internally with the socket and providing ledges in difierent horizontal planes, a crystal mounting unit comprising a bridge mounting member of insulating material, combined electrical connector and mounting supports secured to the mounting member and formed with apertured extensions positioned to overlie the sidewall ledges of the holder, electrical terminal elements fitted to the holder in vertical alignment with the extension apertures and securing screws fitted to the extension apertures and threaded to the terminal elements for eliecting electrical and securing connection therewith and said offset planes of the ledges corresponding substantially to the thickness of the bridge mounting.

5. A frequency determining unit of the character described comprising a holder of insulating material formed with an internal socket for the reception of a crystal mounting unit and with spaced supporting ledge portions, terminal pins positioned in the holder body to underlie the ledges, a detachable crystal mounting unit comprising a bridge mounting member of insulating material, combined electrical connector and mounting supports secured on the mounting member and spaced for bearing upport on the ledges, a crystal and electrodes therefor, crystal supporting means carried by the mounting and electrically connected to the connector and mounting supports and to the crystal electrodes and securing and connector screws fitted to apertures in the connector supports and the ledges and threaded to the terminal pins for securing of the mounting unit and to effect circuit connection with the pins.

6. A frequency determining unit of the character described comprising a holder of insulating material of substantially cylindrical form having an internal socket for the reception of a crystal mounting unit and formed with opposite aligned supporting ledge portions, oppositely positioned terminal pins received in the holder body sidewall to underlie the ledges, a detachable crystal mounting unit comprising a bridge mounting member of insulating material, combined electrical connector and mounting supports secured on the mounting member and extended for bearing support on the ledges, a crystal and electrodes therefor, crystal supporting means carried by the mounting and electrically connected to the connector and mounting supports and to the crystal electrodes, securing and connector screws fitted to apertures in the connector supports and the ledges and threaded to the terminal pins for securing of the mounting unit and to effect circuit connection with the pins and said ledges being arranged in different horizontally spaced planes having spacing substantially corresponding to the thickness of the bridge mounting.

'7. A frequency determining unit of the character described comprising a holder of insulating material formed with an internal socket for the reception of a crystal mounting unit and with opposite aligned ledges, terminal pins positioned in the holder body to underlie the ledges, a detachable crystal mounting unit comprising a bridge mounting member of insulating material, electrical connector and mounting supports secured on the mounting member and oppositely extended for bearing support on the ledges, a crystal and electrodes therefor, crystal supporting means carried by the mounting and electrically connected to the connector and mounting supports and to the crystal electrodes, securing and connector and mounting screws fitted to apertures in the connector supports and the ledges and threaded to the terminal pins for securing of the mounting unit and to effect circuit connection with the pins and said ledges being arranged in different horizontal planes spaced substantially to correspond to the thickness of the bridge mountings.

8. A frequency determining unit of the character described comprising a holder of insulating material formed with an internal socket for the reception of a crystal mounting unit and with spaced supporting ledge portions, terminal pins positioned in the holder body to underlie the ledges, a detachable crystal mounting unit comprising a bridge mounting member of insulating material, electrical connector and mounting supports secured on the upper and lower faces of themountingmember and oppositely extended for bearing support on the ledges, a crystal and electrodes therefor crystal supporting means carried by the mounting and electrically connected to the connector and mounting supports and to the crystal electrodes and screws fitted to the apertures in the connector and mounting supports and the ledges and threaded to the terminal pins for securing of the mounting unit and to eiTect circuit connection with the pins and said ledges being arranged in different horizontal planes spaced substantially to correspond to the thickness of the bridge mounting.

9. A frequency determining unit of the character described comprising a holder of insulating material formed with an internal socket, a crystal mounting unit comprising a bridge mounting member of insulating material, electrical connector and mounting supports secured to the mounting member and formed with apertured extensions positioned to overlie sidewall portions of the holder, electrical terminal elements fitted to the holder in alignment with the extension apertures and securing screws fitted to the extension apertures and threaded to the terminal elements for effecting electrical and securing connection therewith, a crystal and electrodes therefor, said mounting member being formed with a multiplicity of spaced apertures therethrough for crystal supporting posts and said connector and mounting supports being formed to overlie separate series of said apertures, opposite supporting posts fitted each within an aperture in electrical connection with a connector and. mounting support.

10. A piezo-electric crystal structure comprising a rectangular crystal mounting unit of insulating material and a holder element having externally projecting electric terminals and provided internally with means for supporting said crystal mounting unit, said unit having conductive terminals for connection to the crystal electrodes and conductive means secured to opposite sides of the unit connecting the last-mentioned terminals to said projecting electric terminals and serving to attach said unit to said supporting means.

11. A frequency determining unit of the character described comprising an insulating holder, a crystal mounting unit comprising a bridge mounting member of insulating material, combined electrical connector and mounting member supports secured to the mounting member and formed with apertured extensions, electrical terminal elements fitted to the holder in alignment with the extension apertures and securing means fitted to the extension apertures and threaded to the terminal elements for effecting electrical and securing connection therewith.

SAMUEL ALEXANDER BOKOVOY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,978,188 Ciccolella Oct. 23, 1934 2,203,486 Bond June 4, 1940