US3662306A

US3662306A - Adjustably coupled radio frequency transformer

Info

Publication number: US3662306A
Application number: US127566A
Authority: US
Inventors: Robert P Heinis
Original assignee: Arris Technology Inc
Current assignee: Arris Technology Inc
Priority date: 1971-03-24
Filing date: 1971-03-24
Publication date: 1972-05-09
Anticipated expiration: 1989-05-09

Abstract

An adjustably coupled transformer comprising a one-piece coil form, preferably a cylindrical form, made of a plastic material, having two sections separated by an integral deflectable part to permit the axial adjustment of one of the form sections relative to the other, a transformer winding being mounted on each of the coil form sections adjacent the deflectable part, with means for axially adjusting one of the coil form sections relative to the other. The transformer structure is mounted in a transformer housing.

Description

O United States Patent [151 3,662,306 Heinis 1 May 9, 1972 s41 ADJUSTABLY COUPLED RADIO 3,428,929 2/1969 Brown et al ..336/l29 FREQUENCY TRANSFORMER 3,437,968 4/1969 Hildebrandt ..336/1 19 [72] Inventor: Robert P. Heinis, Totowa, NJ. Primary ExaminerThomas J. Kozma [73] Assignee: General Instrument Corporation, Newark, Atwmey James & Franklm Ni 57 ABSTRACT [22] Filed: 1971 An adjustably coupled transformer comprising a one-piece [21] APPL 127,566 coil form, preferably a cylindrical form, made of a plastic material, having two sections separated by an integral deflectable part to permit the axial adjustment of one of the [52] U.S.Cl ..336/ll9,336/129,336/13] form sections relative to the other, a transformer winding [5 [1 Int. Cl. ..H0ll 21/04, H0lf2 l/06 being mounted on each of the coil form sections adjacent the [58] Field of Search ..336/l l5, 1 17, l 18, 1 I9, 129, deflectable part, with means for axially adjusting one of the 336/130, l3 1, I36 coil form sections relative to the other. The transformer structure is mounted in a transformer housing. [5 6] References Cited 6 Claims, 8 Drawing Figures PATENTEDMAY 9 I912 3. 662,306

' sum 1 or 2 INVENTOR 605627 f/E/ll/LS BY $0M ATTORNEYS ADJUSTABLY COUPLED RADIO FREQUENCY TRANSFORMER This invention relates to an adjustably coupled transformer and more particularly to an adjustably coupled double tuned radio frequency transformer.

It is known in the prior art to devise adjustably coupled radio frequency transformers embodying a variety of structural forms. Thus, it is known to provide coil forms which telescope one relatively to the other in order to adjust the coupling between the-transformer coils, or coil forms which embody threaded means for accomplishing the positional change in the transformer coils, or forms which include screws accessible from the outside of the coil assembly for effecting the" adjustable couplingof the transformer coils. It is also known to provide a transformer structure in which the adjustment of the coupling between transformer coils is achieved by thedeforrnation ofparts between the said coils.

The prime object of my present invention relates to the provision of an adjustably coupled transformer and more particularly to an adjustably coupled double tuned radio frequency transfonner embodying the following structural features, devised as improvements in construction operation and use of the adjustably coupled transformers of the stated prior art:

1. An adjustably coupled transformer comprising a onepiece coil form, preferably a cylindrical form, made of a plastic material, having two sections separated by an integral deflectable part to permit the axial adjustment of one of the form sections relative to the other, a transformer winding being mounted on each of the coil form sections adjacent the deflectable part, with means for axially adjusting one of the coil form sections relative to the other;

2. An adjustably coupled transformer having this described structure in which the transfonner is double tuned by the provision of a paramagnetic core mounted directly on the inner wall of each of the coil sections of the cylindrical coil form, the cores being mounted for axial adjustment relative to the transformer windings on the coil sections; and

3. An adjustably coupled transformer of the structure described in which the coil form and all of its parts are enclosed and mounted in a transformer housing with means for mounting the same in the housing in ways to pennit the ready relative adjustment of the coil form sections from the outside of the housing as well as the ready adjustment of the transformer cores from the outside of the housing.

To the accomplishment of the foregoing objects and such other objects as may hereinafter appear, the invention relates to the adjustably coupled transformer as is more particularly defined in the appended claims taken together with the following description and the appended drawings in which:

FIG. I is a front elevational-view of the adjustably coupled transformer of the invention with a part cut away to expose parts of the coil-form and coil winding construction thereof;

FIG. 2 is a top plane view of FIG. 1;

FIG. 3 is a side elevational view of the transformer structure;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is an elevational view of the transformertaken in cross-section in the plane of the line 5--5 of FIG. 1' showing the sections of the coil form andthe transformer coils or windings thereon-in one position of adjustment;

FIG. 6 is a view of the transformer taken in cross-sectionin the plane of the line 6--6 of FIG. 1 (a view similar to that of FIGS) showing the sections of the coil form and the coils or windings thereon in another position of adjustment;

FIG. 7 is a view of the transformer taken in cross-section in the plane of the line 7-7 of FIG. 1, and

FIG. 8 is a view thereof taken in cross-section in the plane of the line 8-8 of FIG. 1.

Referring now more in detail to the drawings and having reference first to FIGS. 5 and ,6 thereof, the adjustably coupled transformer of the invention comprises essentially a onepiece coil form generally designated as 10 having two

sections

12 and 14 separated by an integral deflectable part 16, the

latter to permit axial adjustment of one of the form sections relative to the other, a transformer winding 18 being mounted on one of the said sections such as the coil form section 12 and a transformer winding 20 being mounted on the other section, namely, the coil form section 14, both windings being mounted adjacent the deflectable coil form part l6. The coil form is preferably cylindrical in form and is made of a flexible plastic material such as polypropylene; and the deflectable part 16 is produced by axially slitting a cylindrical part of the coil form and deforming the same-into the shape or formation best depicted in FIG. 5 of the drawings. With this construction the

coil sections

12 and 14 may readily be adjusted axially relative to each otherto change the length of the overall coil form and toadjust the position of the transformer winding 18 with reference'to the transformer winding '20, relative adjustment of these parts effecting the relative movement thereof between the position shown in' FlG. 5 and the position shown in FIG. 6 of the drawings.

The transformer is preferably a double tunedftransformer; and to this end each of the coil form sections (12, '14) is provided with a paramagnetic core mounted and axially adjustable within its coil form section, for axial adjustment relative to the transformer winding on such section. Thus, the coil section 12 is provided with the paramagnetic core 22 and the coil form section 14 is provided with the paramagnetic core 24, each of which is directly mounted, and axially adjustable, as clearly shown in FIGS. 5 and 6, on the inner wall of the coil form 10, the

cores

22 and 24 being externally threaded for this purpose as shown andthe inner walls of the

coil sections

12 and 14 being formed with integral ribs 26 co-acting with the external threads of the

cores

22 and 24.

The transformer structure described also has incorporated thereon the means for axially adjusting the coil form sections relative to each other. This partakes of a part 28 secured to the outer wall of the coil form section 12 at its top. This part 28 preferably is in the form of a collar externally threaded as at 30, the collar being formed with radial extensions 32 for a purpose to be described.

Theadjustably coupled transformer described is enclosed and mounted within a transformer housing 34 having the shape and form clearly shown in the drawings. The coil form 10 is mounted in the housing 34 by the provision of a base member 36 fixedly attached as at 38, 38 to the bottom of the housing, the bottom end of the coil form section 14 being secured to this base member at 40 as best shown in FIGS. 5 and 6 of the drawings. In the top of the housing there is provided a member 42 rotatably mounted in the top end of the housing, the said member preferably comprising a nut internally threaded at 44 for threaded connection with the external threads 30 of the collar 28. The nut 42 is extended laterally as at 46 to engage the walls of the housing34 to stablize rotation of the same, and the housing is formed with

lock tabs

48, 48 which engage the extensions'46'to effect the captivation of the nut and to prevent axial movement thereof during nut rotation. The nut is further provided with a part 50 projecting through the top of the housing 34, the said part being preferably formed as a hex' nut for receiving a socket wrench 55 (FIG. 6) for effecting the rotations of the nut 42.

The collar 28 isformed with radial extensions 32, 32 (previously referred to) which extend to engage the comers of the housing 34 (see particularly FIGS. 7 and 8) to prevent rota tion of the collar. As will now be seen, rotation of the nut 42 will effect the constrained axial movement of the collar 28 to in turn effect the axial adjustment of the-top coil form and winding thereon relative to the bottom coil form and its windmg.

With the adjusting means described, rotation of the nut 42' will readily result in the relative adjustments desired; and the collar 28 is so constructed and supported as to prevent accidental damage to the unit when torque is applied to the ad'- justing nut at its extreme in the up position; in the extreme down position the unit is protected by allowing the threaded collar to completely disengage the nut; and to insure rethreading in this condition, a lead-in section is provided in the threaded collar.

For axially adjusting the

cores

22 and 24, these cores are formed with hexagonal shaped bores 52, 52 access to which by a suitable similarly shaped tool may be obtained through a central opening 54 in the nut 50 and a central opening 56 at the bottom of the coil form section 14.

Suitable terminals

58, 58 are embodied in the base member 36 to which the leads 60, 60 of the windings are attached.

The structure, use and operation and the advantages obtained in the functioning and use of the adjustably coupled transformer of the invention will, it is believed, be fully understood from the above detailed description thereof. It will be further apparent that changes may be made in the structure thereof without departing from the spirit of the invention defined in the following claims,

I claim:

1. An adjustably coupled transformer comprising a onepiece coil form having two sections separated by an integral deflectable part to permit of axial adjustment of one of the form sections relative to the other, a transformer winding on each of the coil form sections adjacent the deflectable part, and means for axially adjusting one of the coil form sections relative to the other.

2. The adjustably coupled transformer of claim 1, in which the coil form is a cylindrical form made of a plastic material, the windings are radio frequency transformer windings, the transformer being doubly tuned by a paramagnetic core mounted directly on the inner wall of each of the coil form sections for axial adjustment relative to the transformer winding on such section.

3. The adjustably coupled transformer of claim 1, in which the coil form, the windings thereon and the adjusting means are enclosed in a transformer housing, the axial adjusting means being fixed to one of the coil form sections, a base member fixedly attaching the other coil form section to one end of the housing, and a member rotatably mounted in the other end of the housing having a threaded connection with the axially adjusting means, rotation of said latter member operating the adjusting means for effecting the axial adjustment of one coil form section relative to the other coil form section.

4. The adjustably coupled transformer of claim 1, in which the coil form is a cylindrical form made of a plastic material, the windings are radio frequency transformer windings, the transformer being doubly tuned by a paramagnetic core mounted directly on the inner wall of each of the coil form sections for axial adjustment relative to the transformer winding on such section, the axial adjusting means being fixed to one of the coil form sections, a base member fixedly attaching the other coil form section to one end of the housing, and a member rotatably mounted in the other end of the housing having a threaded connection with the axial adjusting means, rotation of said latter member operating means for effecting the axial adjusting of one coil form section relative to the other coil form section.

5. The adjustably coupled transformer of claim 3, in which the axial adjusting means comprises a threaded collar fixed to said one of the coil form sections, the said threaded collar being provided with extensions engaging the inner walls of the transformer housing to prevent rotation of the collar and to permit axial sliding movement thereof within the housing, and the member rotatably mounted in the housing comprising a nut threadingly engaging the said collar, the said nut having extensions engaging part of the transformer housing for permitting rotation of the nut and preventing axial movement of the nut.

6. The adjustably coupled transformer of claim 5 in which an axially adjustable paramagnetic core is mounted in each of the coil form sections, one of the cores being accessible from the outside of the housing through an opening in the said nut,

the other core being similarly accessible through an opening in the coil section in which it is mounted.

Claims

1. An adjustably coupled transformer comprising a one-piece coil form having two sections separated by an integral deflectable part to permit of axial adjustment of one of the form sections relative to the other, a transformer winding on each of the coil form sections adjacent the deflectable part, and means for axially adjusting one of the coil form sections relative to the other.

6. The adjustably coupled transformer of claim 5 in which an axially adjustable paramagnetic core is mounted in each of the coil form sections, one of the cores being accessible from the outside of the housing through an opening in the said nut, the other core being similarly accessible through an opening in the coil section in which it is mounted.