US3091062A - Lens de-blocking device - Google Patents

Description

May 28, 1963 J. M. SUDDARTH LENS nmswcxmc DEVICE Filed Sept. 17, 1 962 JACK M. SUDDARTH United States Patent 3,091,062 LENS DE-BLOKING DEVICE Jack M. Suddarth, Muskogee, Okla, assignor to Coburu Manufacturing Company, Inc., Muskogee, Okla, a corporation of Oklahoma Filed Sept. 17, 1962, Ser. No. 224,033 7 Claims. (Cl. 51-277) This invention relates to an apparatus for removing a chucking block from a lens blank after the lens blank has been through an abrading process. More specifically, the invention relates to a hand operated device for efficiently removing a metallic block from the lens surface through the use of very slight pressure and without the use of chemicals.

In the process of generating a lens surface, or in beveling its periphery with conventional grinding and abrading equipment known to the art, it is necessary to attach a chucking block to one surface of the lens blank in order that it may be firmly held and accurately positioned with respect to the cutting tools. The fragile nature of the lens blank makes direct chucking undesirable. There are various methods of attaching the block to the lens and the disclosed embodiment is specifically concerned with removing circular blocks, which are secured to the surface of a lens via a low melting point alloy, from the convex surface of a lens blank.

An objective of this invention is to provide a device which mechanically removes the chucking block from the lens with greatly reduced incidence of lens breakage.

A further objective of the invention is to provide an apparatus for removing a chucking block from a lens and which apparatus is inexpensive in its manufacture and rugged and simple in its operation.

A further objective of this invention is to provide a lens de-blocking device in which the lens surface is engaged by a ring-like member such that an operator may cause a progressive separating force from one side of the lens to the other.

A still further objective of the invention is to provide means whereby the above-mentioned progressive line of force may commence along any selected diameter of the lens.

A further objective of the invention is to provide an apparatus of the character described in which the elements are so constructed that Wear plates are conveniently mounted and are readily replaced to increase the life of the device itself.

These and other important objectives and advantages of the invention will hereinafter become more fully apparent from the following description of the drawings, illustrating a presently preferred embodiment of the invention, and wherein:

FIGURE 1 is a side elevation of a lens blank having a chucking block secured thereto;

FIGURE 2 is an exploded perspective of the principal elements of this invention;

FIGURE 3 is a partial side elevation showing the assembled elements just prior to inserting the lens block assembly into the apparatus; and

FIGURE 4 is a cross-sectional view showing the elements in their lens de-blocking position.

Referring now more particularly to the drawings wherein like numerals indicate like parts, the numeral designates the presently preferred embodiment of this invention. The embodiment is provided with a base 12 from which a cylindrical standard 14 upwardly extends.

The standard consists of an annular wall 14, and is 3,991,062 Patented May 28, 1963 "ice bottomed at 18 by a portion of base 12. A spindle 20 is received in the standard 14 and is fixedly secured thereto by an Allen screw or the like 22 through the threaded apertures 24 and 26, of the standard and spindle respectively. The cylindrical spindle is tapered about its upper end at 28. The spindle is centrally bored at 30 to receive a coil spring 32, and about the upper surface thereof, is provided .with an upwardly extending annular flange 34 which defines a block receiving pocket or seat 36. The inner periphery 38 of Wall 36 is vertical, and the outer periphery is defined by the previously mentioned taper 28. The flange 34 is terminated by the annular upper edge 39.

Between the spindle 20 and the wall 16 a ledge 40 is formed. An expanding ring assembly 42 is adapted to slide over the spindle 20 and be rotatably supported on ledge 40. The assembly 42 is comprised of a first lower ring 46 and a second upper ring 48 of substantially the same dimensions.

The lower ring is formed with an outwardly and upwardly extending arm 50 which is apertured at 52. Formed along the periphery of upper ring 48, adjacent to arm 50, is a bifurcated arm 54 which is apertured at 56 and 56'. Arms 50 and 54, along with pin 58, form a pivotal connection between the rings.

Diametrically opposed to the arm 50, the lower ring is provided with an outwardly and upwardly extending arm 60 which is apertured at 62. Pivotally secured to arm 60 is an operating lever 64 by way of a pin 66. Immediately above the arm 60, and spaced therefromQa bearing lug 68 protrudes from upper ring 48. A wear plate 70 is secured to the underside of lug 68 via the screw 72.

The operating lever is comprised of a handle 74, a fulcrum recess through which pin 66 extends, and a forwardly extending boss 76 which is received in the space between the lug 68 and arm 60. A screw 78, hav- .ing a wear plate head 80, is secured to the boss in mating relationship with wear plate 70.

A pair of biasing springs 82 and 84 extend between the upper and lower rings and maintain the wear plates and 78 in engagement with one another. The springs normally bias the rings 46 and 48 toward each other to a substantially edge-to-edge relationship. A screw 85 extends through arm 60 below the pivot point, and will adjustably limit the pivoting movement of the operating lever by engaging a side wall of recess'65. The upper ring is counterbore at 86 to receive an annular fiber member 88. As will become more apparent hereinafter, the fiber member provides a relatively non-abrasive contact surface between the apparatus and the lens blank.

In FIG. 1 there is shown a lens blank L secured to a circular block B by the previously mentioned low melting point alloy A. It is common practice to coat the convex side of the lens with a quick dry plastic prior to applying the alloy. This coating protects the lens surface and makes block removal an easier operation.

The assembled elements are shown in cross-sectional elevation in FIG. 3, just prior to the insertion of the workpiece. It should be noted that in the assembled arrangement, the upper edge of fiber ring 88 extends slightly vabove the upper edge 39 of the seat and the coil spring ring 88 is spaced from pivot pin 58, the top edge of the fiber ring, which is in annular engagement with the lens, exerts a continuous progressive force from left to right, as viewed in FIG. 4. This progressive force along two semi-circular arcuate lines provides an annular line of force about the lens blank which greatly reduces the amount of breakage encountered in other lens de-blocking devices. In those instances where an operator is confronted with a particularly tight bind between the lens and block, the operator can rotate the ring assembly 42 about the spindle 20, while repeatedly depressing handle 64, until a point about the seal is found that is weak enough to break.

Since, the block itself cannot tilt, because of the close tolerances between it and the inner periphery of the seat, no other apparatus is required to vertically secure it with respect to the lens blank. When the upper ring applies the pressure to the lower surface of the lens the lens block, of course, due to a tendency to tilt, will bind itself slightly within flae seat. A slight tap on the block will normally break the bind and along with the spring the block is easily removable from the seat, and the device is ready to receive another workpiece.

In a general manner, while there has been disclosed in the above-description, what is deemed to be the most practical and efiicient embodiment of the invention, it should be well understood that the invention is not limited to such an embodiment as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the present invention as comprehended withinthe scope of the accompanying claims. 7

I claim:

1. A device for removing a block from the Surface of a lens-blank comprising a base, a standard of lesser crosssection than said base extending upwardly therefrom and defining a step with said base, an upwardly extending flange about the top of said standard defining a seat having an inner wall configuration closely approximating the outer periphery of said block, a base ring rotatably received aboutsaid standard and support by said ledge, an upper ring about said standard pivotally securedto said base ring, said upper ring having a first position wherein its upper edge is parallel to and slightly above the upper edge of-said flange and is in engagement with the surface of said lens when said block is inserted in said seat, and means to tilt said upper ring from said base ring whereby said lens 'is tilted away from said block.

2. A device for removing a block from the surface of a lens blank comprising a base, a standard of lesser crosssection than said base extending upwardly therefrom and defining a step'with said base, an upwardly extending flange about the top of said standard defining a seat having an inner wall configuration closely approximating the outer periphery of said block, a first ring rotatably received about said standard and support by said ledge, and \a second ring about said standard pivotally secured to said base ring, said second ring having a first position wherein its upper edge is parallel to and extends slightly above the upper edge of said flange and in engagement with the surface of said lens when said block is inserted in said seat, and means to tilt said first ring upwardly from said base ring such that said lens is tilted away from said block by a pressure exerted by said second edge. V

3. A device for removing a block from the surf-ace of a lens blank comprising, a base, a standard of lesser crosssection than said base extending upwardly therefrom and defining a step with said base, an upwardly extending flange about the top of said standard defining a seat having a vertical inner wall configuration closely approximating the outer periphery of said block and an inwardly directed taper along the outer wall thereof, a lower ring rotatably received about said standard and supported by said ledge, an upper ring about said taper and pivotally secured to said base ring, said upper ring having a first position wherein its upper edge is parallel to and extends slightly above the upper edge of said flange and is in engagement with the surface of said lens when said block is inserted in said seat, and means to tilt said upper ring from said base ringwhereby said lens is tilted away from said block.

7 4. A device for removing a block from the surface of a lens blank comprising a base, a standard of lesser crosssection than said base extending upwardly therefrom and defining a step with said base, an upwardly extending flange about the top of said standard defining a seat having a vertical inner wall configuration closely approximating the outer periphery of said block and an inwardly directed taper along the outer wall thereof, a lower ring rotatably received about said standard and supported by said ledge, anupper ring about said taper and pivotally secured to said base ring, a coil spring in said seat, said upper ring having a first position wherein its upper edge is parallel to and extends sli htly above the upper edge of said flange and is in engagement with the surface of said lens when said block is inserted in said pocket, and means to tilt said upper ring from said base ring to a second position whereby said block is unable to tilt in said seat, said lens is tiltable away from said block by said lever, and said coil spring aids in removing said block from said seat after the lens is separated from said block.

5. A device for removing a block from the surface of a lens blank comprising a base, a standard of lesser crosssection than said base extending upwardly therefrom and defining a step with said base, an upwardly extending fiange about the top of said standard defining a seat having an inner wall configuration closely approximating the outer periphery of said block," a lower ring rotatably re-- ceived about said standard and supported by said ledge, an upper ring about said standard, means pivotally securing said lower ring to said ring at a first point along their peripheries, said upper ring having a first position wherein its upper edge is parallel to and extends slightly above the upper edge of said flange and is in engagement with the surface of said lens when said block is inserted in said seat, an operating lever pivotally attached to said lower ring at a second point diametrically opposed to said first point, one end of said lever in contact with the lower edge of said upper ring whereby when the other end of said lever is depressed, said upper ring and 'said lens are tilted away from said block.

6. A device for removing a block from the surface of a lens blank comprising a base, -a standard extending outwardly from said 'base and defining a step therewith, a flange about the outer end of said standard defining a seat having an inner wall configuration closely approximating the outer periphery of said block, a first ring rotatably received about said standard and supported by said ledge, a second ring about said standard pivotally secured to said first ring, said second ring having a first position wherein a first edge is prarallel to and slightly above the edge of said flange and is in engagement with the surface of said lens when said block is inserted in said seat, and means to tilt said first ring from said second ring whereby said lens is tilted away from said block. a g

7. An apparatus for removing a sealed chucking block from the convex surface of a lens blank comprising upper and lower coaxial annular rings circumscribing said block,

said upper ring in annular engagement with said convex surface of said blank, means rotatably mounting rings with zrespect to said block, a hinge pivotally connecting said upper ring to said lower ring, a seat rigidly securing said block against a. tilting movement, and second means to pivot said upper n'ng with respect to said block about said hinge and against said lens.

References Cited in the file of this patent UNITED STATES PATENTS Pellow et a1. Dec. 1, 1914 Bugbee Oct. 22, 1918 Hill June 19, 1923 Long et al. Oct. 30, 1951 Allen et :al. Mar. 31, 1939

Claims (1)

1. 7. AN APPARATUS FOR REMOVING A SEALED CHUCKING BLOCK FROM THE CONVEX SURFACE OF A LENS BLANK COMPRISING UPPER AND LOWER COAXIAL ANNULAR RINGS CIRCUMSCRIBING SAID BLOCK, SAID UPPER RING IN ANNULAR ENGAGEMENT WITH SAID CONVEX SURFACE OF SAID BLANK, MEANS ROTATABLY MOUNTING RINGS WITH RESPECT TO SAID BLOCK, A HINGE PIVOTALLY CONNECTING SAID UPPER RING TO SAID LOWER RING, A SEAT RIGIDLY SECUR-

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