BACKGROUND OF THE INVENTION
The present invention relates to hydro-electric parts and more particularly to a manufacturing process to make a valve ball which has two layers made up with punching method.
The valve ball is a popular part used in the hydro-electric engineering. The manufacturing process of a prior art valve ball can be categorized of punching, forging and/or roller ramming, etc., FIG. 12 shows a valve ball 70 which is made with forging process and has a pair of identical hemi-spherical housings 71 each of which has a passage way 72 in the center. The pair of hemi-spherical housings are connected together by welding means to finish a valve ball 70. Due to that a forging object has to be through a chemical disposal. There must be the residual chemicals remained on the surface of the valve ball 70 which may harm the human health if it is used in a water supply system. However, most of the producers are now gave up this process. FIGS. 13 to 15 show another prior art valve ball 80 which is made with continuous punching method. So it punches a copper plate 81 at first, then punch the plate 81 into the small arcuate pieces 81′, and punch again the small arcuate pieces 81′ into the large circular pieces 81″ and then punch the large circular pieces 81″ into the hemi-spherical pieces. Finally, put a pair of the hemi-spherical pieces respectively into an upper and a lower mold to facilitate a welding procedure. A valve ball is therefore accomplished after the polishing of the connection seam. This manufacturing process is somewhat too complicated in comparison with other manufacturing process because it wastes time and is unpractical.
FIGS. 16 to 19 show still another prior art valve ball which also adapts repeated punching process. It punches a piece of plate into a cup shaped semi-finished product 91 and punch the semi-finished products 91 with an upper and lower mold into the hemi-spherical shapes. Then remove the flat circular bottoms of the hemi-spherical shapes that became a pair circular openings 921 and then punch a rectangular through hole 922 in a lateral arcuate wall for connecting a valve stem. You'll see that the repeated punching activities not only cause stripes around the opening 921 which have to dealt with after the finishing of the valve ball, but also causes uneven thickness on the lower arcuate portion. So it produces large rate of unqualified products.
FIGS. 20 to 24 introduce a further prior art valve ball which is manufactured with roller ramming process. This process is punching a flat plate 1 into a hollow cylindrical shaped semi-finished product 2 with flap 3 therearound and remove the flap 3 and the bottom 2001, then punch the cylindrical shaped semi-finished product into the spherical shape 4 and the punch a rectangular hole 5 in a lateral periphery, a valve ball is therefore finished. This process includes two times of cutting action and because the roller ramming product is always coursed uneven arc on the whole body that produce high rate of unqualified products, too.
SUMMARY OF THE PRESENT INVENTION
The present invention has a main object to provide a manufacturing process to make a valve ball which is manufactured with punching method to rapidly produce a double-layer valve ball in good quality of uniform arc and thickness. Besides, it provides high rate of qualified products and convenient assembly.
Accordingly, the manufacturing process to make a valve ball of the present invention comprises generally the following steps:
- a) prepare pieces of flat circular metallic plates 10;
- b) put the plates 10 one by one between an upper mold 20 and a lower mold 21 in a punching machine and punched the plates 10 into a top hat shaped configuration which includes a crown 11a and a brim 10a;
- c) punch the top of the crown into a circular opening 12b and the brim 10a an indentation in a circumference;
- d) put the top hat shape inversely in a depression 411 of another lower mold 41 which has a round top 412 and another upper mold 40 which has a symmetrical ¼ spherical grooves around a central cylindrical post by which the top hat shape is punched into a bowl shaped hemi-sphere 10c including a bottom, a rectangular indentation 13b and a tubular inner wall (not shown);
- e) combine a pair of identical hemi-sphere shapes together with their indentations engaged with each other to form a rectangular retaining through hole;
- f) polish the connection seam and the outer surface of the entire body. A qualified valve ball which has an inner wall, an outer wall in uniform arc and thickness is accomplished.
This process may promote the qualified proportion and suit to mass production.
The present invention will become more fully understood by reference to the following detailed description thereof when read in conjunction with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view to show a flat circular metallic plate disposed between an upper and a lower molds,
FIG. 2 is a perspective view to show that the plate is punched into a top hat configuration,
FIG. 3 is a sectional view to show that the top hat shaped configuration is put into an upper mold ready to punch by a lower mold,
FIG. 4 is a perspective view to show that the top of the hat is punched into an opening and the brim thereof being punched a rectangular indentation,
FIG. 5 is a sectional view to show that the top hat shaped configuration is put into a lower mold and gets ready to punch by an upper mold,
FIG. 6 is a perspective view to show that the top hat shaped configuration is punched into a hemi-spherical shape including an inner wall in the center,
FIG. 7 is a sectional view of FIG. 6,
FIG. 8 is a perspective view to show that a pair of identical hemi-spherical shapes are combined together by means of welding,
FIG. 9 is a sectional view of FIG. 8,
FIG. 10 is a sectional view to show that the valve ball is polished by a polishing machine,
FIG. 11 is a perspective view to show a finished valve ball of the present invention,
FIG. 12 is a perspective to show a first prior art valve ball which is manufactured by forging process,
FIG. 13 to 17 are the plane, perspective and sectional views to show a second prior art valve ball which is manufactured by punching process,
FIGS. 18 and 19 are the sectional views to show a third prior art valve ball which is of an improvement of the second prior art valve ball, and
FIG. 20 to 24 are the sectional and perspective view to show a fourth prior art valve ball which is manufactured by roller ramming process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIGS. 1 and 2 of the drawings, the manufacturing process to make a valve ball of the present invention comprises the following steps:
- a) prepare a plurality of flat circular metallic plates 10;
- b) put the plates 10 one by one between a first upper and a lower molds 20 and 21 of a punching machine, wherein the first upper mold has a cylindrical depression 201 in the center and the first lower mold has a cylindrical punch 211 slidably disposed within the central bore engageable with cylindrical depression 201;
- c) the plate 10 is punched by the punch 211 and pressed by the upper and lower molds 20 and 21 simultaneously to become a top hat shaped configuration which has a cylindrical crown 11a and a brim 10a;
- c) put the crown 11a of the top hat into a central bore 31 of a second cylindrical upper mold 30 and punched by a cylinder punch 32 of a second lower mold, so that the top of the crown 11a becomes a circular opening 12b and the brim 10a becomes 10b because of a rectangular indentation 13b is formed in a circumference (as shown in FIGS. 3 and 4);
- e) put the opened crown 12b of the top hat shape inversely into a lower punch 41 of a third lower mold which has a central depression 411 engageable with the central post surrounded by ¼ circular groove 401 in a third upper mold 40, meanwhile, the lower punch 41 has a round top engageable with the groove 401. When the third upper mold 40 is closed to the brim 10b of the top hat shape and the punch 41 strokes upward, so that the top hat shaped becomes a hemi-spherical shape including an opened top and a rectangular indentation 13b in a rim (as shown in FIGS. 5 and 6);
- f) combine each pair of the identical hemi-spherical shapes 10c together and connected by welding means with their depressions 13b engaged with each other to form a rectangular retaining through hole 13d capable of engaging with a valve stem and their inner walls 14c combined into a cylindrical passage way 14d. A valve ball 10d is therefore formed (as shown in FIGS. 7, 8 and 9);
- g) trim and smooth the welding seam and conduct a solidification process;
- h) polish the outer surface by sleeving the valve ball on a rotatable rod 50 and engage the outer surface of the valve to an introrse surface 61 of a polishing machine. A qualified valve ball is therefore finished after removing the rotatable rod 50 (as shown in FIGS. 10 and 11).
conclusively, during the step punching the top hat shape 10b into a hemi-spherical shape 10c, the crown of the top hat shaped is disposed tightly into a central depression 411 of a lower punch 41 which prevent the working piece from displacement problem. So that the hemi-sphere shapes 10c are of uniform arc and thickness in order to promote the rate of qualification. Not as the prior art manufacturing processes which use only one piece of flat plate through repeated punching steps that can't avoid the problems of displacement of the working piece and deformation of the products that cause a high rate of unqualified products.
Although the forging process (as discussed in FIG. 12) can avoid the problems of the displacement and the deformation. But the residual chemical remained in the surface is harmful to human health if the valve ball is used in a water supply system.
The valve ball 10d of the present invention, except the outer housing, it has a inner passage way 14d which provides a reinforcement function to cause the valve ball more durable. Further, the previously punched rectangular retaining through hole can prevent the valve ball from deformation.
Note that the specification relating to the above embodiment should be construed as an exemplary rather than as a limitative of the present invention, with many variations and modifications being readily attainable by a person of average skill in the art without departing from the spirit or scope thereof as defined by the appended claims and their legal equivalents.
Patent Application
20050274014
