FIXTURE FOR GRINDING APPARATUSES

Abstract

A fixture (10) for grinding apparatuses includes a base (12), a plurality of supporting components (14), and a pressure controlling apparatus (16). The base includes a cavity (126) containing a fluid medium (129), and the base defines a plurality of through holes (122) communicating with the cavity. One section of each supporting component is movably mounted in a through hole, and an end of each supporting component is exposed through its respective through hole and is configured for supporting an apparatus to be ground. The pressure controlling apparatus is connected to the base and facilitates selectable adjustment of a pressure of the medium.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to fixtures for grinding apparatuses and, more particularly, to a fixture for grinding apparatuses which prevents workpieces from being damaged.

2. Description of Related Art

Many kinds of workpieces need to be ground into an appropriate shape before use. When the workpieces are ground using grinding apparatuses, fixtures are used to hold the workpieces. Magnetic and mechanical clamps are widely used in grinding procedures.

Referring to FIG. 1, a typical magnetic clamp 40 fixes a workpiece 50 magnetically. A grinding wheel 60 grinds a surface of the workpiece 50 flat. However, usually a portion contacting with the magnetic clamp 40 of the workpiece 50 is not flat. Therefore, magnetism between the magnetic clamp 40 and the workpiece 50 is distributed unevenly, and the workpiece 50 is more likely to be deformed by uneven magnetic forces acting between the magnetic clamp 40 and the workpiece 50 and by action of the grinding wheel 60, when the workpiece 50 is ground. After the workpiece 50 is ground and released from the magnet, the resulting ground surface may be uneven. Thus, the typical magnetic clamp 40 tends to be unsuitable for precision manufacturing.

If the workpiece 50 is fixed by a mechanical clamp when being ground, the workpiece 50 is even more likely to be deformed, the ground plane being similarly distorted after the workpiece 50 is released from the clamp.

Therefore, a new fixture for grinding apparatuses is desired in order to overcome the above-described shortcomings.

SUMMARY OF THE INVENTION

In a preferred embodiment thereof, a fixture for a grinding apparatuses includes a base, a plurality of supporting components, and a pressure controlling apparatus. The base includes a cavity containing a fluid medium, and the base further has a plurality of through holes defined therein, in communication with the cavity. One base-mounted end of each supporting component is movably mounted in a respective through hole of the base, and another supporting end of each supporting component is exposed through its respective through hole. The pressure controlling apparatus is connected to the base and controls pressure of the medium.

Other advantages and novel features will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the fixture can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the fixture. Moreover, in the drawings, like reference numerals designate corresponding parts through out the several views.

FIG. 1 is a schematic view of a workpiece being ground by a grinding wheel and being fixed by typical magnetic clamp;

FIG. 2 is a schematic view of a fixture, in accordance with a preferred embodiment;

FIG. 3 is a cutaway view of the fixture along the line III-III in FIG. 2; and

FIG. 4 is a working schematic view of the fixture, in accordance with the preferred embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings in detail, FIG. 2 shows a fixture 10, in accordance with a preferred embodiment. The fixture 10 includes a base 12, a plurality of supporting components 14, and a pressure controlling apparatus 16. The pressure controlling apparatus 16 cooperates with the base 12 and the supporting components 14 to secure a workpiece 20, as represented in FIG. 4.

Also, referring to FIG. 3, the base 12 includes a working surface 120, two supporting blocks 124, and a cavity 126. The supporting blocks 124 are respectively mounted on two opposing sides of the working surface 120. The base 12 defines a plurality of through holes 122 on the working surface 120, between the two supporting blocks 124. The through holes 122 communicate with the cavity 126. The base 12 also defines a connecting hole 128 formed in a side face thereof, and the connecting hole 128 communicates with the cavity 126 and the outside of the base 12. Some fluid medium 129 (schematically shown) is contained in the cavity 126. The medium 129 can be a liquid, such as oil or another hydraulic liquid, or a gas, such as compressed air. The medium 129 could instead, potentially, be a mixture of a solid powder and a fluid carrier, the solid component helping to support the supporting components 14 and the nature of the suspension offering fluid properties.

Each supporting component 14 includes a piston 142, a central supporting pole 144, and an arcuate head portion 146. One end of the supporting pole 144 carries the piston 142, and the other end of supporting pole 144 carries the head portion 146. Each end of the supporting pole 144 carrying a respective piston 142 is movably mounted in one through hole 122 and faces the cavity 126 and the medium 129 therein. Meanwhile, each end of the supporting pole 144 with a respective head portion 146 thereon is exposed out of the working surface 120, through its respective through hole 122 (i.e., exposed above both the working surface 120 and its respective through hole 122). Each supporting pole 144 is slidably mounted in its respective through hole 122. Thus, by selectively sliding a supporting pole 144 of a given supporting component 14, the vertical position of the head portion 146 of each supporting component 14 can be adjusted. Beneficially, a low-friction, clearance fit exists between a given supporting pole 144 and the corresponding through hole 122, to promote efficient motion therebetween and to reduce the potential for friction. It could also prove advantageous for both the piston 142 and the head portion 146 to have a diameter in excess of that of the through hole 122, to prevent accidental dislodging of a given supporting component 14 during operation.

The pressure controlling apparatus 16 includes a motor 160, a pipeline 161, and a valve 162. One end of the pipeline 161 is connected with the motor 160. The valve 162 is mounted in the pipeline 161. The motor 160 (i.e., a hydraulic pump) is configured for communicating with a fluid and adjusting the pressure associated therewith.

In assembly, one end of the pipeline 161 is connected to the base 12 and is aligned with the connecting hole 128. The base 12 is connected to the pressure controlling apparatus 16, via the connecting hole 128 and the pipeline 161, and the valve 162 is opened. In this way, the pressure controlling apparatus 16 can adjust pressure of the medium in the cavity 126. In particular, this pressure adjustment can be achieved by using the valve 162 to selectively control the medium flow into or out of the cavity 126.

Referring to FIG. 4, when the fixture 10 is used to fix the workpiece 20, two opposite ends of the workpiece 20 are respectively placed on the two supporting blocks 124, and the mid portion of the workpiece 20 is supported by the supporting components 14. When the workpiece 20 is pressed or attracted (e.g., via magnetism or gravity) towards the base 12, a pressure of the medium is kept within an appropriate range by the pressure controlling apparatus 16. Furthermore, a length of the exposed portion of each supporting portion 14 can be adjusted using pressure of the medium to correspond to the place in which the head portion 146 of the supporting portion 14 is brought into contact with the workpiece 20. In this way, the supporting components 14 support the workpiece 20 with a symmetrical supporting force and are able to correspond, as a group, to the shape of the work piece 20. Because of this support control, distortion of the workpiece 20 is prevented. When pressure of the medium is adjusted to a preferred value, the valve 162 is closed, and the pressure of the medium 129 is stabilized.

Additionally, the base 12 can be magnetic and thus able to attract and hold a ferromagnetic workpiece 20 thereon. The supporting blocks 124 can potentially be omitted.

It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Claims

1. A fixture for grinding apparatuses, comprising:

a base including a cavity containing a fluid medium, the base having a plurality of through holes defined therein, the through holes each communicating with the cavity;

a plurality of supporting components, a central portion of each supporting component being movably mounted in a through hole, and a support end of each supporting component being exposed above its respective through hole and above the base; and

a pressure controlling apparatus connected to the base and configured for adjusting a pressure of the medium.

2. The fixture as claimed in claim 1, wherein the pressure controlling apparatus includes a pump and a pipeline, one end of the pipeline is connected with the pump.

3. The fixture as claimed in claim 2, wherein the base defines a connecting hole, the base being connected to the pressure controlling apparatus via the connecting hole and the pipeline.

4. The fixture as claimed in claim 2, wherein the pressure controlling apparatus includes a valve, the valve is mounted in the pipeline.

5. The fixture as claimed in claim 1, wherein the medium is comprised of one of a liquid and a gas.

6. The fixture as claimed in claim 1, wherein the central portion of each supporting component defines a corresponding supporting pole, and a support end of each supporting component defines a head portion, each head portion being carried by a respective supporting pole.

7. The fixture as claimed in claim 1, wherein the base is magnetic and is thereby able to attract a ferromagnetic workpiece theretoward.

8. The fixture as claimed in claim 1, wherein the base includes a working surface and two supporting blocks, the supporting blocks are respectively mounted on two opposite sides of the fixture, with the working surface extending therebetween, and the through holes are defined within the working surface.

9. A fixture for grinding apparatuses, comprising:

a base including a working surface and a cavity containing a fluid medium;

a plurality of supporting components configured for supporting workpieces, one section of each supporting component being exposed out of the working surface, and length of the exposed section of each supporting portion is adjusted by changing a pressure of the medium; and

a pressure controlling apparatus configured for adjusting the pressure of the medium.

10. The fixture as claimed in claim 9, wherein the pressure controlling apparatus includes a pump and a pipeline, and one end of the pipeline is connected with the pump.

11. The fixture as claimed in claim 10, wherein the base has a connecting hole defined therein, the base being connected to the pressure controlling apparatus via the connecting hole and the pipeline.

12. The fixture as claimed in claim 10, wherein the pressure controlling apparatus includes a valve, and the valve is mounted in the pipeline.

13. The fixture as claimed in claim 9, wherein the medium is comprised of one of a liquid and a gas.

14. The fixture as claimed in claim 9, wherein the base defines a plurality of through holes communicating with the cavity, each supporting component includes a piston, a supporting pole, and a head portion, one end of the supporting pole carries the piston, and another end of the supporting pole carries the head portion.

15. The fixture as claimed in claim 14, wherein each end connecting with a piston faces the cavity, and each end with a head portion is exposed above the working surface.

16. The fixture as claimed in claim 9, wherein the base is magnetic and is thereby able to attract a ferromagnetic workpiece theretoward.

17. The fixture as claimed in claim 9, wherein the base includes two supporting blocks, the supporting blocks are respectively mounted on two opposite sides of the working surface, with the working surface extending therebetween, and the through holes are defined in the working surface between the two supporting blocks.