Convergence coil assembly for color television

Abstract

The convergence coil assembly comprises a frame plate with guides at an angle of 120° to receive three coil housings which are slidable radially to compensate for variations in the diameter of the tube neck. At their inner ends the housings have flanges receiving a resilient clamp ring to draw them against the tube neck. The clamp ring may be hooked to provide different degrees of tension. Indicators provide visual alignment of the magnets with a desired part of the gun. A permanent magnet on the outer end of the core of the electromagnets is rotatable for adjustment, and there are means to hold the adjustment.

We claim: 
     
       1. A convergence coil assembly for color television comprising a frame plate .[.having.].  .Iadd.with .Iaddend.a hole large enough to receive the neck of a color tube of maximum contemplated diameter .[.,.].  and having a plurality of .[.substantially equally spaced.].  guide means fixed thereon and .[.spaced circumferentially.].  .Iadd.substantially equally circumferentially spaced .Iaddend.about said hole, .Iadd.and extending generally radially with respect to said hole, .Iaddend.and a plurality of housings operatively connected to .[.the.].  .Iadd.said .Iaddend.guide means .Iadd.respectively .Iaddend.and movable within said guide means toward and away from said hole, magnet means operatively connected to said .[.housing, and means acting on said housings to urge them radially inward toward said hole to adjust the positions of said housings for tube necks of different diameters, said guide means being fixed during the movement of said housings thereby to maintain the relative spaced positions about said hole of said housings and magnet means during said movement.]. .Iadd.housings, flanges on said housings adjacent the inner ends thereof, and a clamp ring engaging said flanges and active to urge them and their respective housings towards one another and against the tube. 
     
     
       2. A convergence coil assembly as defined in claim 1, .[.in which there is a clamp ring to draw the housings toward one another and against the tube neck, and.]. in which .[.the.]. .Iadd.said .Iaddend.clamp ring is made of relatively stiff resilient wire, and in which the end parts of the clamp ring project outwardly, the first of said end parts being additionally bent toward the second of said end parts and being provided with a hook at its tip to engage the second part in order to put the ring under tension. 
     
     
       3. A convergence coil assembly as defined in claim 2, in which the second outwardly bent part of the clamp ring is additionally reversely bent to provide a third part spaced from the second part and dimensioned to receive the aforesaid hook of the first part, but with a different degree of clamp tension than when the hook engages the second part. 
     
     
       4. A convergence coil assembly as defined in claim 3, in which the frame plate has indicators thereon which are located and visible between the .[.coil.]. housings near the tube neck and which serve to indicate the center line of the magnets in the housings, said indicators facilitating visual alignment of the magnets .Iadd.operatively connected to .Iaddend.with a desired part of the gun in the neck of the tube as seen through the transparent glass of the neck. 
     
     
       5. A convergence coil assembly as defined in claim 4, .Iadd.in which said magnet means is electromagnetic and comprises a core and a coil, and .Iaddend.in which there is a permanent magnet resting against the outer end of the core of the electromagnets in each housing, said permanent magnet being rotatable for adjustment purposes, and .[.coil.]. housing and said frame plate being open at opposed parts of said permanent magnet to facilitate manual rotational adjustment of the same. 
     
     
       6. A convergence coil assembly as defined in claim 5, in which the rotatable permanent magnet has a center hole and is retained by means of a leaf spring mount, the middle part of which has a centering teat received in the center hole in the permanent magnet to locate and pivot the same, the middle part of said leaf spring bearing tightly against said permanent magnet and acting as a friction brake to help retain the adjustment of the same. 
     
     
       7. A convergence coil assembly as defined in claim 6, in which the .[.coil.]. housing has a lock shoe extending over the center portion of the leaf spring, and has an oscillatable locking lever carrying a locking cam at its inner end, said cam bearing against said locking shoe to wedge the same tightly against the leaf spring and the permanent magnet in order to lock the rotational adjustment of said permanent magnet. 
     
     
       8. A convergence coil assembly as defined in claim 7, in which the coils have fine wire connected to external leads of heavier wire, and in which the side of the .[.coil.]. housing as molded has strain relief means, with a plurality of holes for said leads, said holes opening at one end into slots transverse to the holes for receiving soldered connections between the fine magnet wire and the heavier lead wire, and said strain relief means including an arm outside the other ends of the holes for reversely bending the lead wires and thereby additionally anchoring them against external stress. 
     
     
       9. A convergence coil assembly as defined in claim 1, in which the frame plate has indicators thereon which are located and visible between the .[.coil.]. housings near the tube neck and which serve to indicate the center line of the magnets in the housings, said indicators facilitating visual alignment of the magnets with a desired part of the gun in the neck of the tube as seen through the transparent glass of the neck. 
     
     
       10. A convergence coil assembly as defined in claim 1, .Iadd.in which said magnet means is electromagnetic and comprises a core and a coil, and .Iaddend.in which there is a permanent magnet resting against the outer end of the core of the electromagnets in each housing, said permanent magnet being rotatable for adjustment purposes, said .[.coil.]. housing being open at a part of said permanent magnet to facilitate manual adjustment of the same. 
     
     
       11. A convergence coil assembly as defined in claim 10, in which the rotatable permanent magnet has a center hole and is retained by means of a leaf spring mount, the middle part of which has a centering teat received in the center hole in the permanent magnet to locate and pivot the same, the middle part of said leaf spring bearing tightly against said permanent magnet and acting as a friction brake to help retain the adjustment of the same. 
     
     
       12. A convergence coil assembly as defined in claim 10, in which the rotatable permanent magnet has a center hole and is retained by means of a leaf spring mount, the ends of which are reversely bent and directed inwardly and being notched to fit around the core of the electromagnets, and the middle part of which has a centering teat received in the center hole in the permanent magnet to locate and pivot the same, the said middle part of said leaf spring bearing tightly against said permanent magnet and acting as a friction brake to help retain the adjustment of the same. 
     
     
       13. A convergence coil assembly as defined in claim 10, in which the .[.coil.]. housing has a lock shoe extending over the permanent magnet, and has an oscillatable locking lever carrying a locking cam at its inner end, said cam bearing against said locking shoe to wedge the same tightly toward the permanent magnet in order to lock the rotatinal adjustment of said permanent magnet. 
     
     
       14. A convergence coil assembly as defined in claim 11, in which the .[.coil.]. housing has a lock shoe extending over the permanent magnet, and has an oscillatable locking lever carrying a locking cam at its inner end, said cam bearing against said locking shoe to wedge the same tightly toward the permanent magnet in order to lock the rotational adjustment of said permanent magnet. 
     
     
       15. A convergence coil assembly as defined in claim 1, .Iadd.in which said magnet means is electromagnetic and comprises a core, and .Iaddend.in which the coils have fine wire connected to external leads of heavier wire and in which the side of the housing as molded has strain relief means, with a plurality of holes for said leads, said holes opening at one end into slots transverse to the holes for receiving soldered connections between the fine magnet wire and the heavier lead wire, and said strain relief means including one arm outside the other ends of the holes for reversely bending the lead wires and thereby additionally anchoring them against external stress.