SU1281379A1 - Apparatus for working optical parts - Google Patents

Abstract

The invention relates to the abrasive machining of optical parts and can be used for grinding and polishing spherical surfaces. The purpose of the invention is to simplify the design and expand the technological capabilities of the device. It contains the spindle part 8, the drive tool, the leash 2

Description

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which is located coaxially with the spindle part, the clamping mechanism and the mechanism for changing the clamping force, depending on their mutual position, made in the form of coaxially mounted on the driver 2 with the possibility of relative axial movement of the elastic split cone 1, the petals of which are in contact with the non-working surface of the tool 7 and with an additional female element 4 installed with the possibility of axial movement and fixation. During processing while moving

the tool axis from the center to the edge of the part of its non-working surface 6 begins to contact with the petals of the cone 1, which causes an increase in the deformation of the petals and, accordingly, additional clamping force. When the tool moves in the opposite direction, the additional force decreases and when the tool axis reaches its initial position relative to the part axis, all the petals come out of the contact and only the axial pressing force acts on the tool. 1 3.p. f-ly, 3 ill.

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The invention relates to the abrasive machining of spherical surfaces, such as grinding and polishing of optical parts.

The aim of the invention is to simplify the design and expand the technological capabilities of the device.

Figure 1 shows the device, section, general view; Fig. 2 shows the position of the cone petals when the axes of the part and the tool do not match; Fig. 3 is a diagram of changing the rigidity of the cone petals using an additional female element with a curved surface.

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The device consists of an elastic clamping element 1, made in the form of a split multi-petal cone mounted on a leash 2 of an upper link drive mechanism, a nut 3 designed to fix the axial position of the cone 1, an additional female arm 4 mounted axially relative to the cone 1 and a locking screw 5 fixing the position of the enclosing element 4 relative to the cone 1. The petals of the cone 1 are in contact with the non-working surface 6 of the tool during operation. that 7 when the tool axes 7 and the workpiece spindle 8 do not match.

The device works as follows.

During shaping, the tool 7 moves relative to the surface of the part 8 under the action of the drive mechanism of the upper link, which closes with the tool with the aid of the ball tip of the driver 2. The pressing force required to remove the allowance from the surface of the part is also transmitted to the tool through the ball tip of the driver. At different positions of the tool axis 7 and the axis of the part 8, the pressure in the contact zone is distributed according to a different law.

In this case, in the part of the edge part, in which the part of the tool is observed to come out of contact with the surface to be treated, forces arise, at least 2-3 times exceeding the average pressure value over the part surface. Therefore, an intensified removal of the allowance takes place here and the edge collapses; the formation of an undesirable chamfer, the elimination of which further causes an increase in labor intensity and impairs the optical properties of the part. These phenomena occur when the tool axis moves from the center of the part to the edge. In this case, the tool 7 is rotated. When a certain initial angle of rotation is reached, its non-working surface 6 begins to contact with the petals of the cone 1. The contact area of the tool 7 and the cone petals is always in the upper part of the tool opposite to

overflow area. Increasing the smoothness of the turn causes a further increase in the deformation, and the petals, which, with a known stiffness, cause an increase in additional downforce. If a large product or block of workpieces is being processed, then the stiffness of the pressure lobes may be insufficient to create the necessary additional force. In this case, during adjustment, the female element 4 is lowered by a certain distance and fixed by a screw 5. In this case, during rotation of the tool 7, its non-working surface 6 contacts the tab, which, as it deviates from the initial position, begins to increase its rigidity. As shown in FIG. 3, when the end of the petal deviates by the value of OA, its length is equal to OD (linear section and increase in additional force occurs linearly). Subsequently, in the section ABC, the length of the deformable part of the petal decreases and becomes, respectively, EA, FB and COP. The rigidity of the petal increases, respectively, the additional force increases by a unit — the angle of rotation of the tool. Similar phenomena occur with all the contacting petals of an elastic pressure member. When the tool moves in the opposite direction, the additional force decreases and when the tool axis reaches the initial setpoint of the deflection angle relative to the part axis, all the petals come out of the contact and only the axial pressing force acts on the tool.

The implementation of the clamping element in the form of a multi-leaf split cone allows the additional clamping force to vary depending on the change in the position of the axes of symmetry of the tool and the workpiece, and increasing the angle of inclination of the tool axis relative to the axis of the part causes an increase in the additional clamping force applied to the non-working surface of the tool that is equidistant processed. The tool surface, to which the tool applies with additional clamping force at any angular position

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cop is in the upper part. At the same time, the adverse pressure increase that occurs in the lower part of the tool, caused by an increase in the contact force and the influence of the edge effects, is compensated by an additional pressing force from the side opposite to the tool axis. This achieves

 О a decrease in the size of the strap of the product, i.e. the formation of an undesirable chamfer in the edge-to-cross part, lowering the specified optical characteristics of the finished part. This improves the quality of the treated surface.

The possibility of axial movement of the cone relative to the trap allows the angular position of the tool 20 to be changed, at which additional clamping force begins to occur depending on the size of the tool, the radius of the sphere, and the diameter of the workpiece.

The introduction of additional coverage-. element allows the cone to change its hardness depending on the hardness of grinding the glass being processed and the nature of the operation.

 (grinding or polishing),

The implementation of the working surface of the enclosing curvilinear element (e.g., involute) allows, if necessary,

35 to change the stiffness of the petals depending on the inclination of the tool axis relative to the axis of the part.

Claims (1)

Invention Formula 40 1. A device for processing optical parts, comprising a spindle of a part, a drive for moving a tool, the lead of the output link of which is located coaxially with the spindle of the part, J5 the mechanism for clamping the tool to the parts and the mechanism for changing the clamping force depending on their mutual position, characterized in that, in order to simplify the design of Q and to expand the technological capabilities of the device, the mechanism for changing the clamping force is coaxially mounted on a leash with the possibility of Its axial movement of the elastic split cone, the petals of which are intended to come into contact with the non-working surface of the tool, and the additional female element, has a cue .Z fig.Z