US3456218A

US3456218A - Unitary plastic retainer ring for relatively rotatable magnetic rings

Info

Publication number: US3456218A
Application number: US663101A
Authority: US
Inventors: Robert Richard Melone
Original assignee: Illinois Tool Works Inc
Current assignee: Illinois Tool Works Inc
Priority date: 1967-08-24
Filing date: 1967-08-24
Publication date: 1969-07-15
Anticipated expiration: 1986-07-15
Also published as: NL6812097A; GB1183267A; DE1762745A1; DE1762745B2; ES152097U; ES152097Y; FR1575147A

Description

United States Patent 3,456,218 UNITARY PLASTIC RETAINER RING FOR RELA- TIVELY ROTATABLE MAGNETIC RINGS Robert Richard Melone, Des Plaines, Ill., assignor to Illinois Tool Works Inc., Chicago, Ill., a corporation of Delaware Filed Aug. 24, 1967, Ser. No. 663,101 Int. Cl. H01f N30 US. Cl. 335-212 3 Claims ABSTRACT OF THE DISCLOSURE An annular retainer to be mounted on the neck of a television tube and including circumferentially spaced and oppositely extending substantially axial finger elements to frictionally engage the neck of a television tube, and further including circumferentially spaced transversely extending lug or shoulder means to retain therebetween relatively rotatable beam-adjusting ring magnets which may be mounted on the retainer prior to assembly as a unit with the neck of a television tube.

The invention aims to provide an annular retainer with oppositely extending substantially axial finger elements resiliently to engage the neck of a television tube resisting axial and rotational movement thereon and having shoulder means therearound to frictionally grip a pair of ring magnets adapted for relative rotation for beamadjusting purposes and maintain the rings in adjusted positions.

Another object of the invention is to provide a retainer substantially of the above type wherein certain of the axially extending fingers are elongate to project in opposite directions and arranged in assembled position to resiliently and frictionally engage the neck of a television tube.

A further object of the invention is to provide a retainer substantially of the above type wherein certain of the axially extending finger elements include transverse shoulder means cooperating with additional shoulder means to retain ring magnets therebetween for relative rotation.

The invention still further aims to provide a retainer of the above type which may have the ring magnets initially assembled therewith for later association as a composite unit with the neck of a television tube.

The above and other objects of the invention will in part be obvious and will be hereinafter more fully pointed out.

In the accompanying drawing:

FIG. 1 is a fragmentary perspective view showing the retainer and the ring magnets assembled with the neck of a television tube;

FIG. 2 is an end elevation of the retainer;

FIG. 3 is a sectional view taken substantially along the line 33 of FIG. 2;

FIG. 4 is a sectional view, similar to FIG. 3, showing the magnet rings mounted on the retainer and the entire assembly associated with the neck of a television tube; and

FIG. 5 is a sectional View taken substantially along the line 5-5 of FIG. 2.

Referring to FIG. 1, there is shown a television tube and its reduced neck portion 10a on which the retainer 12 is assembled. As illustrated, the retainer 12 has assembled therewith two magnetic beam-adjusting

rings

14, 15, each with finger engaging lug portions 14a, 15a, respectively, deflected from the planes of the respective rings for ease of grasping and manipulation when in certain proximate positions. The use of two annular permanent magnets arranged side by side is known for adjusting the electron beam for correct reproduction of the images on the screen area. Further description is believed unnecessary as it is known that by rotating either or both of the magnets, the resultant magnet field transverse to the axis of the neck of the television tube may be changed.

With reference to FIGS. 2 and 3, the retainer 12 is shown as including an annular body or ring portion 16 having spaced around the circumference thereof finger elements 18, each being identical. Each finger element 18 includes

portions

18a, 18b extending substantially axially of the body portion 16 and in opposite directions therefrom. Each finger portion 18b is provided with an inwardly directed offset end portion 20 which is somewhat thickened and is arcuate to resiliently engage the neck of the television tube when assembled therewith. Each oppositely extending finger portion 18a is arcuate and has the longitudinal edges thereof terminating in inwardly directed

wall portions

22, 22a in the form of ribs and with the ends thereof slightly beveled or curved to snugly fit against the adjacent surface of the neck of the television tube when assembled therewith.

As more clearly shown in FIG. 5, there are additional finger elements 24, each being identical, and circumferentially spaced around the body portion 16 of the retainer and extending in one substantially axial direc tion thereof. As illustrated, each of these finger elements 24 extends in the direction of the elongate finger elements 18b away from the body portion. Each finger element 24 includes a longitudinally disposed and inwardly projecting rib 24a. The outer surface of each finger element 24 is tapered, as at 24b, to facilitate assembly of the

magnetic rings

14, 15 thereover. This tapered portion 24b terminates at its inner edge in an outwardly directed shoulder 26 adapted to snugly engage the surface of an adjacent magnetic ring 15 assembled therewith. The finger elements 24 are resiliently spread around the body portion 16 between the finger elements 18.

The body portion 16 of the retainer also includes circumferentially spaced spring arms 28, each being identical. These spring arms are disposed between

adjacent finger elements

18, 24 and extend radially outwardly from the body portion to spaced shoulder surfaces resiliently engaging the surfaces of the other adjacent magnetic ring 14 assembled therewith. Each of these radially extending spring arms 28 are of reduced cross section adjacent the annular body portion 16 to provide the desired resiliency permitting rotation of the ring magnets under manual manipulation while resisting movement from positions of relative adjustment.

In assembling the retainer with the neck 10a of the television tube, assume that the

ring magnets

14, 15 have been initially assembled with the retainer. This is accomplished by passing the side-by-

side ring magnets

14, 15 axially of the retainer and along the inclined surfaces 24b of the finger elements 24. This will force the finger elements inwardly permitting the ring magnets to snap into position between the spring arms 28 and the shoulders 26. In this assembled position, the ring magnet 14 will abut the shoulders 26 and the ring magnet 15 will have its outer surface engaged by the spaced spring arms 28 thus maintaining the assembled rings in position on the retainer. The spring pressure exerted by the arms 28 against the ring magnet 15 is such as to maintain the ring magnets in surface engagement and with the ring 14 engaging the shoulders 26 of the finger elements 24. The spring pressure is such as to permit relative adjustment by relative rotation of the ring magnets but to also maintain the ring magnets in any position to which they have been adjusted. The composite assembly of the retainer and the ring magnets is then associated with the neck 10a of the television tube by relative axial movement therebetween. The assembled position of the retainer and the ring magnets, as shown in FIGS. 4 and 5, is one wherein the inwardly offset portions 20 of the fingers 18 are spread slightly to the position shown in FIG. 4 in order to resiliently grip the neck of the tube. At the same time, the

rib portions

22, 22a of the finger elements 18 are spread slightly to the position shown in FIG. 4 so that they, too, resiliently grip the surface of the neck of the tube. In this manner, the retainer and the magnets are resiliently and securely positioned on the neck of the tube. The gripping force of the

finger elements

18a, 18b on the tube surface is such as to fixedly mount the retainer thereon while permitting relative rotation of the ring magnets for adjustment purposes under the relatively lighter gripping action of the spring fingers 28 against the adjacent ring magnet 15.

The retainer is made from a suitable heat-resistant plastic material to guard against distortion under influence of heat developed in the tube. To further guard against heat influence, it is to be noted that the contact areas between the retainer and the neck of the tube are rather small. For example, the

ribs

22, 22a provide narrow contact surfaces. Ribs 24a are designed to normally remain clear of the surface of the tube. However, when the retainer is applied to a tube neck having a diameter on the high tolerance side the retainer is slightly distorted and there is a tendency for finger elements 24 to move inwardly. The ribs 24a then engage the tube neck and reinforce elements 24 to ensure positive engagement of shoulders 26 with the ring magnets. Likewise, the surface contact between the finger portions 20 and the neck of the tube are reduced as these finger portions are spread outwardly for resilient gripping to the position of FIG. 4. Still further, the outer surface of the annular body portion 16 is recessed, as at 30, exteriorly of finger elements 18 and so provide peripherally spaced gaps for air circulation within the inner edges of the ring magnets. Said recesses 30 also assist in enhancing the resiliency of finger elements 18.

While illustrating one form of the invention, it is to be understood that changes in details of construction and arrangement of parts may be made without departing from the scope of the invention as set forth in the appended claims.

I claim:

1. A one piece continuous plastic retainer ring for attachment around the neck of a television tube and adapted to support a pair of relatively rotatable magnetic beam-adjusting rings around the tube axis, and comprisremoval of the assembled rings in the opposite direction,

said finger elements having the recited shoulder means includinginwardly directed substantially rigid rib means for engaging the neck of the television tube to provide rigidity to said shoulder means to form a positive stop to prevent said axial movement of the adjacent magnetic ring in one direction and said space lug means providing biasing means to resiliently maintain the assembled magnetic rings in position between the said lug means and the said shoulder means to thereby insure maintenance of adjusted relation between said rings.

2. A plastic retainer ring as claimed in claim 1, wherein certain of the finger elements include resilient finger portions projecting to opposite sides of the body portion with the finger portions at one side of the body portion having inwardly ofiset end portions for engagement with the neck of the television tube when assembled therewith and with the finger portions on the opposite side of the body portion having spaced inwardly projecting rib means to engage the neck of the television tube when assembled therewith.

3. A plastic retainer ring as claimed in claim 1, wherein the finger portions, the finger elements with said shoulder means, and the lug means are circumferentially spaced from one another around the periphery of the body portion, and wherein the body portion is recessed along the outer surface thereof at spaced intervals to provide air gaps plus resiliency to said finger elements.

References Cited UNITED STATES PATENTS 2,922,908 I/ 1960 Heller 31384 X 3,303,443 2/1967 McCabe et a1. 335-212 X 3,332,046 7/1967 Melone 3352l2 3,376,450 4/1968 Franklin 335212 X ROBERT SEGAL, Primary Examiner