KR980008454A - Hemispherical grinding machine - Google Patents

Abstract

A hemispherical surface polishing apparatus for polishing a hemispherical surface of a workpiece having a spherical surface such as a spherical bearing is disclosed. The hemispherical surface polishing apparatus according to the present invention is characterized in that the hemispherical surface grinding apparatus according to the present invention is a self-aligning (self-aligning) polishing machine in which a working pressure is applied to the center- (-) electrode to the workpiece, and a tool (not shown) is attached to the workpiece by a combination of the rotational motion and the swinging motion, So that the electrolytic solution can be supplied to the machining area to enable electrolytic dressing during machining. According to this aspect, it is possible to easily process a workpiece having a large curvature, which is difficult to perform in the case of general lapping or polishing. In addition, the tool can be easily replaced according to the material of the workpiece and the degree of wear of the tool, and high machining efficiency can be expected.

Description

Hemispherical grinding machine

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus for precisely finishing a surface of a workpiece, and more particularly, to an electrolytic dressing hemispherical surface polishing apparatus for polishing a hemispherical surface of a workpiece having a spherical surface such as a bearing of a high- .

Generally, machined parts such as bearings of high-speed rotating bodies, spherical lenses, and ball joints have machined surfaces whose surface portions are formed in a hemispherical shape. The hemispherical surface of such a hemispherical workpiece requires precise finishing so as to increase the surface roughness in order to increase the fluidity or decrease the frictional resistance. Such hemispherical surface finishing work has traditionally been done in a form that depends on the work of skilled workers using finishing tools such as grinding wheels or wraps and polishers.

However, such finishing through manual work has a problem that not only the processing efficiency is lowered but also the processing quality such as precision and surface roughness is lowered.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems occurring in the prior art, and it is an object of the present invention to provide a method and apparatus for efficiently processing a hemispherical surface of a hemispherical workpiece such as a bearing or a spherical lens of a high- And it is an object of the present invention to provide a hemispherical surface polishing apparatus capable of dressing.

FIG. 1 is a schematic side view showing a hemispherical surface polishing apparatus according to the present invention. FIG.

FIG. 2 is a front view of FIG. 1;

FIG. 3 is a schematic partial perspective view showing the main part of FIG.

FIG. 4 is a schematic diagram illustrating the operation of the recess shown in FIG. 1; FIG.

FIG. 5 is a schematic plan view showing a rotary table of a hemispherical surface polishing apparatus according to the present invention. FIG.

FIG. 6 is a schematic cross-sectional view showing the "A" part of FIG. 1 and FIG.

FIG. 7 through FIG. 9 show examples of the types of tools used in the hemispherical surface polishing apparatus according to the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS

10: base frame 11: drive motor

11a: pulley 12: belt

13: rotation table 14: link member

15: swing motion shaft 16: support

16a: Needle bearing 17: Connecting member

18: DC brush 19: container

20: Grinding tool 21: Pneumatic cylinder

22: ball joint 23: tool body 24: spindle motor

25: Electronic brake 30: Tool for lapping

40: tool for polishing 100: power source

131: Coupling ball for adjusting the range of motion P: Rotating table center of rotation

D: Tool outer diameter H: Tool height

h: electrolyte supply passage I: electrolyte supply pipe

R: Tool spherical radius W: Hemispherical workpiece

M: Screw size for tool tightening

According to an aspect of the present invention, there is provided a hemispherical surface polishing apparatus including a base frame, a first driving source provided on the base frame, a rotating table connected to the first driving source and rotated, A motion converting means for converting the rotational motion of the rotary table to the oscillating motion of the motion shaft by connecting the rotary table and the motion axis to each other, An actuator cylinder for supporting a tool formed so as to be capable of machining a hemispherical surface of a predetermined workpiece; a jig member for supporting the workpiece so as to be able to contact the tool; and a second drive source for rotationally driving the jig member To form corresponding electrodes on the tool and the workpiece, respectively, so as to enable electrolytic dressing of the tool It characterized in that it comprises a power supply for supplying a circle.

In the hemispherical surface polishing apparatus according to the present invention, in particular, the rotary table is provided with a plurality of engagement holes for allowing the engagement of the motion converting means, and the centers of the engagement holes are distant from the central point of the rotary plate And the rotary table is connected to the output shaft of the driving source by a belt.

Preferably, the motion converting means comprises a link member, one end of which is coupled to the rotation table so as to be able to flow, and the other end of which is movably coupled along the outer peripheral surface of the motion shaft.

Preferably, the actuator cylinder has a ball joint coupled to the tool at an end of the piston rod.

The tool has a machining portion formed to accommodate the hemispherical surface of the workpiece in a line-to-line contact or a surface-to-surface contact state. The machining portion is made of diamond, Al2O3, CBN, SiC, cast iron, And the like.

Hereinafter, an electrolytic dressing hemispherical polishing apparatus according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 to 6 are views schematically showing the overall configuration and the main part of the hemispherical surface polishing apparatus according to the present invention. The hemispherical surface polishing apparatus according to the present invention includes a driving motor (not shown) And a rotary table 13 connected to the output shaft of the rotary shaft 11 by a belt 12 so as to be rotatable. 3 to 5 illustrate the rotary table 13 and the recesses around the rotary table 13, wherein the rotary table 13 has a distance from its rotation center point C at different positions A plurality of engagement holes 131 are formed. The rotary table 13 and the motion shaft 15 are connected to the base frame 10 in a state in which one end of the motion shaft 15 is coupled to the base frame 10, And are interconnected by a member (14). That is, one end of the link member 14 is movably coupled to one of the plurality of engagement holes 131 of the rotary table 13, and the other end thereof is configured to surround a part of the outer circumferential surface of the pivot shaft 15 And is slidably coupled along the outer circumferential surface of the swing shaft 15. [0033]

4, the other end of the link 14 slides along the pivot shaft 15 by the rotational movement of the rotary table 13, Thereby enabling the swinging motion with respect to the lateral direction. Reference numeral 16 denotes a support for fluidly supporting one end of the swing shaft 15, and 16a denotes a needle bearing provided on the support 16.

FIG. 6 is a schematic cross-sectional view showing the "A" portion of FIG. 1 and FIG. 2 in which the pneumatic cylinder 21 is arranged in parallel with the connecting member 17 Respectively. Accordingly, the pneumatic cylinder 21 can be interlocked with the swing motion of the pivot shaft 15. [ A ball joint 22 is provided at an end of the piston rod of the pneumatic cylinder 21. A tool support member 23 for supporting a tool for polishing the hemispherical surface 30 of the workpiece W ) Are combined. The workpiece W is provided at the central portion of the tool support member 23 and the tool 30 with a passage h for supplying the machining liquid to the machining portion of the workpiece W. The workpiece W is supported by the base frame 10, For example, by a jig member 25 such as a collet chuck provided so as to be rotatable by an air spindle motor 24 provided in the spindle motor 24. The tool 30 and the jig member 25 are electrically connected to the power source 100 so that electrodes corresponding to each other can be formed so that a structure . Reference numeral I denotes a machining liquid inlet, and 25 denotes an electromagnetic brake connected to shorten the braking time of the air spindle motor 24. [ Reference numeral 19 denotes a container for collecting and circulating the processing liquid (or electrolytic solution) that has been supplied to the processing site.

Operation of the hemispherical surface polishing apparatus according to the present invention having the above structure will be described with reference to the drawings.

When the rotary table 13 is rotated by the drive motor 11, the upper end of the pivot shaft 15 is pivotally moved in the left and right direction by the interference of the support part 16 at the lower end with the link member 14, . That is, the link member 14 slides up and down along the pivot shaft 15 by the rotation of the rotary table 13. [ At this time, since the lower end of the pivotal shaft 15 is formed as a fixed end in a state of being pivotally coupled by the support portion 16, the upper end forming the free end is not limited to the force due to the sliding motion of the link member 14 It is pushed in the left and right direction. This state is, for example, a state in which the upper end rotates in a state where the lower end of the pivot shaft 15 is a fixed point, such as a wiper motion of an automobile. In the strict state, the motion locus for one point of the upper end, Thereby causing a rocking motion in the direction. The pivotal motion of the pivotal shaft 15 causes the pneumatic cylinder 21 to pivot to interlock with the pivotal movement of the pneumatic cylinder 21 so that the tool 30 coupled to the piston rod of the pneumatic cylinder 21 is moved Is in contact with the hemispherical surface of the wafer W, and polishing is performed. At this time, the pneumatic cylinder 21 appropriately presses the tool 30 through the piston rod, and the work W is machined by mutual contact in a state of being rotated by the jig member 23. That is, the tool 30 performs lateral pivotal motion with respect to the hemispherical surface of the work W and applies a machining pressure in the direction of the center of the work W to adjust the rotational center of the work W during machining And has a self-adujusting structure that can be formed. Therefore, the tool 30 is pivotally moved in the lateral direction by the pivot shaft 15, and at the same time, receives the rotational force caused by the rotational motion of the workpiece W, and rotates. Since the hemispherical surface of the workpiece W and the entire machined portion of the tool 30 are in surface contact with each other while being pressed against the central portion of the workpiece W during machining by the combination of the rotational motion and the swing motion, Can be performed.

5, the width of the swinging motion with respect to the upper end of the swing shaft 15 is set to a predetermined value in any one of the plurality of engagement holes 131 provided in the rotary table 13, ) Is connected. For example, in FIG. 5, the swing motion width of the upper end of the pivot shaft 15 when the link member 14 is coupled to the arbitrary engagement hole 131a is X-X ', and the link member 14 is engaged with the engagement hole 131b The yawing motion width is Y-Y '.

Therefore, according to the hemispherical surface polishing apparatus of the present invention, appropriate working conditions can be selected by adjusting the swing motion width of the swing shaft 15 according to the size, the processing accuracy, the material, etc. of the hemispherical surface of the workpiece.

As shown in FIG. 6, the tool 30 and the jig member 25 are electrically connected to the power source 100 so as to form corresponding electrodes, Electrolytic dressing can be performed. That is, the jig member 25 may be formed by setting a dressing electrode member in place of a workpiece using, for example, a chuck such as a collet, applying a positive voltage to the tool 30, (-) voltage is applied to perform electrolytic dressing. At this time, the electrolytic solution is supplied to the dressing portion through the machining liquid supply passage h. This processing liquid (or electrolytic solution) is introduced into the passage h through the injection port connected to the outside, for example, around the pneumatic cylinder 21 or the inside of the cylinder and the center of the tool 30 and the tool support member 23. [ Or a conventional method such as supplying one side of the tool 30 or directly from one side of the tool support member 23 to the machining site (or the dressing site) can be used. Reference numeral 18 denotes a DC brush for electrolytic dressing.

The machined portion of the tool 30 is formed so as to be able to receive the hemispherical surface of the workpiece W in a surface-contact state. FIGS. 7 to 9 illustrate a tool used in the hemispherical surface grinding apparatus according to the present invention Fig.

The tool illustrated in FIG. 7 is a grinding tool 30, the support 31 is made of ordinary steel, and the machining portion 32 is made of diamond, aluminum oxide (Al2O3), CBN, SiC, Thereby enabling process electrolytic dressing in precision grinding. When the process electrolytic dressing is added at the time of precision grinding, the sharpness of the grinding blades can be maintained at all times, and mirror-surface processing is possible, and the machining efficiency can be increased.

The tool illustrated in Fig. 8 is a tool 30 'for lapping, and the entire tool is made of cast iron (GCD 70 or so), bark light, plastic or the like. In the lapping process, the lapping material is mixed with the working fluid and supplied. However, according to the characteristics of the apparatus of the present invention, the tool can be easily replaced due to the coupling by the ball joint.

The tool illustrated in FIG. 9 is a tool 30 "for polishing, the support 31" is made of steel, plastic or the like and the machined portion 32 "is made of a nonwoven abrasive, urethane rubber, And a conventional polishing pad material is attached.

The above-mentioned tools can be used by appropriately selecting the diameter D, the height H, the hemispherical radius R and the ball joint fastening screw size M according to the specifications of the workpiece.

As described above, the electrolytic dressing hemispherical surface polishing apparatus according to the present invention applies a working pressure to the center of the workpiece by the oscillating motion of the tool, which is brought into contact with the hemispherical surface of the workpiece, and is centered on the rotation axis of the workpiece during machining And a rotational motion caused by the rotational motion of the workpiece is transmitted to the workpiece so that the hemispherical surface can be precisely machined by the combination of the rotational motion and the oscillating motion, -) electrode is electrically connected to form a (+) electrode on the tool, and an electrolytic solution is supplied to a machining area to enable electrolytic dressing during machining. According to the apparatus of the present invention, it is possible to easily process a workpiece having a large curvature, which is difficult to perform in a case of general lapping or polishing. In addition, the tool can be easily replaced according to the material of the workpiece and the degree of wear of the tool, and high machining efficiency can be expected.

Claims (9)

A first driving source provided on the base frame, a rotation table connected to the first driving source and rotated, a motion shaft coupled to the base frame so as to be pivotally movable, A motion converting means for connecting the shafts to convert the rotary motion of the rotary table into a swing motion of the motion shaft, and a tool provided to be interlocked with the motion shaft and capable of machining the hemispherical surface of the predetermined workpiece A second driving source for rotating the jig member; a second driving source for rotating the jig member so as to be able to be brought into contact with the tool; And a power supply unit for supplying power to form the hemispherical surface Abrasive device. The hemispherical surface polishing apparatus according to claim 1, wherein the rotating table is provided with a plurality of engaging holes for allowing the motion converting means to engage. The hemispherical surface polishing apparatus according to claim 2, wherein a center of the coupling hole is formed to have a different distance from a center point of the rotary plate. 2. The hemispherical surface polishing apparatus according to claim 1, wherein the rotating table is connected to the output shaft of the driving source by a belt. The hemispherical surface polishing apparatus according to claim 1, wherein the motion converting means is a link member, one end of which is coupled to the rotation table so as to be movable and the other end is a link member movably coupled along the axis of motion. The hemispherical surface polishing apparatus according to claim 1, wherein the actuator and the tool are connected by a ball joint. The hemispherical surface polishing apparatus according to claim 1, wherein the tool and the tool supporting member are provided with a passage for supplying a working fluid. The hemispherical surface polishing apparatus according to claim 1, wherein the tool has a machining portion formed to accommodate the hemispherical surface of the workpiece in a surface contact state. The hemispherical surface polishing apparatus according to claim 1, wherein the second driving source is an air spindle motor equipped with an electromagnetic brake. ※ Note: It is disclosed by the contents of the first application.