DESC:FIELD OF INVENTION

The present invention relates to dies used in press machines. In particular, the present invention relates to multipurpose die for used in press machines. More particularly, the present invention relates to a topless die for a variety of press operations.

BACKGROUND OF THE INVENTION

Sheet metal parts are normally manufactured on metal presses, which are generally hydraulic, pneumatic, and mechanical presses for producing metal components in high volumes.

These press tools are of different types for performing various sheet metal pressing operations like, blanking, piercing, bending, forming, forging, trimming etc. Accordingly, these press tools are specified as blanking tool, piercing tool, forming tool, forging tool, trimming tool and bending tool respectively.

For example, the conventional dies for performing the aforesaid metal pressing operations involve a two-part die, i.e. a top die for mounting cutter or punch and a bottom die for mounting die buttons, bottom cutters having cavity where metal scrap is accumulated for subsequent removal.

DISADVANTAGES WITH THE PRIOR ART

The following are the disadvantages with such two-part dies for metal pressing operations discussed above:

In any conventional die for doing any operation like punching, trimming or piercing we need to have a typical die which consist of top die and bottom die shoe, in top die the cutter or punches are mounted and in the bottom-die the die buttons, bottom cutters of cavity is there where the scrap can be accumulated and removed.
This process is completely performed manually by using labor-intensive operations for cutting away the scrap from pressed part to be reused for making other parts.

OBJECTS OF THE INVENTION

Some of the objects of the present invention - satisfied by at least one embodiment of the present invention - are as follows:

An object of the present invention is to provide an improved die for performing sheet metal pressing operations to manufacture metal components.

Another object of the present invention is to provide a single-piece die for performing sheet metal pressing operations to manufacture metal components.

Still another object of the present invention is to provide an improved die which avoids labor-intensive activities while manufacturing sheet metal components.

Yet another object of the present invention is to provide a die which reduces set-up time for its mounting during the manufacture of sheet metal components.

A still further object of the present invention is to provide a die requires less material and is therefore low-cost for manufacturing sheet metal components.

A yet further object of the present invention is to provide an improved die which substantially increase the productivity while manufacturing sheet metal components.

These and other objects and advantages of the present invention will become more apparent from the following description, when read with the accompanying figures of drawing, which are however not intended to limit the scope of the present invention in any way.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a single-piece die for manufacturing sheet metal components from scrap sheet metal pieces by conducting a variety of pressing operations, such as cutting, trimming, blanking, punching, piercing, notching, flanging, bending depending on the shape of the sheet metal part to be manufactured.

Typically, the die comprises:

• a bottom-die plate for mounting a plurality of cutting edges;

• a punch holder configured with a column to accommodate a spring therein; and

• the punch holder mounting a plurality of punches;

wherein pressed metal parts are manufactured by cutting and trimming from a sheet metal piece by pressing the punches on the punch holder by moving down the press machine ram.

Typically, the die is configured as a topless die for pressing operations such as cutting or trimming of extra sheet metal from the metal part to be manufactured by means of the punches on pressing against the punch holder.

Typically, the punch holder is held on the column by means of punch holder bolts.

Typically, the sheet metal piece is located in the die by means of stoppers provided on the bottom die plate.

Typically, the spring is configured as a separator of the punch holder from the punches.

Typically, the die comprises:

• a bottom-die plate for mounting a punch holder;

• a punch holding pad fitted with punches mounted on the punch holder;

• the punch holder mounting a plurality of punches;

• a plurality of locators for locating the sheet metal piece for manufacturing the sheet metal part therefrom; and

• die buttons mounted in a cavity supported by risers;

wherein pressed metal parts are manufactured from the sheet metal piece by pressing the punches by moving down the press machine ram and guided springs are provided for preventing lateral deflection thereof during the pressing operation by means of the punch holding pad.

Typically, the die is configured as a topless die for pressing operations of punching or piercing the sheet metal piece to form the metal part therefrom by moving down the punches against the bottom die plate.

Typically, the spring functions as a separator of punch holder and punches.

Typically, the spring absorbs the press machine ram force, preferably in the range of about 100 to 600 tons.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will be briefly described with reference to the accompanying drawings, wherein:

Figure 1 shows a conventional arrangement of die-set used in sheet metal presses for manufacturing pressed components.

Figure 2 shows the process flow in the aforementioned conventional manual operation for making press metal parts.

Figure 3 shows a first embodiment of the topless die configured in accordance with the present invention for conducting a variety of pressing operations on sheet metal parts.
Figure 4 shows another embodiment of the topless die configured in accordance with the present invention for conducting a variety of pressing operations on sheet metal parts.

DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS

In the following, the topless die for sheet metal pressing operations and configured in accordance with the present invention will be described in more details with reference to the accompanying drawings without limiting the scope and ambit of the present invention in any way.

Figure 1 shows a conventional arrangement of die-set used in sheet metal presses for manufacturing pressed components. It includes a punch holder 2 or top die shoe, for holding the punch with help of die plate 5 and a punch backing plate 3; and a bottom die shoe or die holder 8 for mounting die buttons or punching plate 7 for shaping outer profiles of the sheet metal components. A stripper plate 6 is used for separating finished components from scrap material and for an easy ejection of the sheet metal part the die. This is a conventional process for punching or trimming of the sheet metal components by using this die. Often, the scrap generated from one part is first manually cut by using scissors to shape it for further use to make another part therefrom. However, this process is performed completely manually and by using labor-intensive methods.

Figure 2 shows the process flow in the aforementioned conventional manual operation for making press metal parts. Here, a plan was conceived to make the process easier and more productive by making an in-house scrap reutilization die, which could cut the unwanted material and thus make scrap reusable for the scrap cutting process. This process includes taking a blank metal sheet at step 10; making a first sheet metal component at step 20; manually cutting the scrap generated after making the first sheet metal component (during step 10) at step 30 for making another sheet metal component; at step 40, reusing the scrap removed (at step 30) from the edges; and making at step 50, another sheet metal component from the scrap obtained from the first component. However, the conventional die, if made, requires a new top and bottom die shoe and other associated material. Moreover, the set-up time for mounting these top and bottom dies on the press is quite high, which leads to a loss of the productivity of the sheet metal press. Further, the development cost of these new dies is also very high and the required material is also not available.

Figure 3 shows a first embodiment of the topless die 50 configured in accordance with the present invention for conducting a variety of pressing operations for manufacturing sheet metal parts. For eliminating the all above mentioned problems and obstacles (Figs. 1-2), a unique die configuration is developed and implemented in the press shop, in which only one bottom die plate 20 is used, whereupon both cutting edges are mounted on die 50. A punch holder 12 is made as a column 14 having springs 16 placed inside it. A punch 18 is mounted thereon, such that when the ram of the press comes down and presses the punch 18 against the punch holder 12, the part 30 (not visible) which is located in the clearnace between the punch 18 and punch holder 12, is cut or trimmed and thus the cutting or trimming operation is completed. The part 30 is located in die 50 with the help of stoppers 22 provided on the bottom die plate 20. The punch holder 12 is held on the column 14 by means of holder bolts 24. This is a very simple arrangement for various sheet metal pressing operations like cutting or trimming etc.

Figure 4 shows another embodiment of the topless die configured in accordance with the present invention for conducting a variety of pressing operations on sheet metal parts. In this exemplary embodiment, the punching and piercing die 100 has a different operation and use. The die 100 is made with the same configuration by using the bottom die shoe 110 for mounting the punch holder 112 and by eliminating the top die shoe completely. Here, a punch holding pad 114 is mounted on the bottom die shoe 110 with help of guided springs 116 to avoid deflection of springs sideways during the operations. A punch holder 112 and punches 118 is mounted on the punch holding pad 114. The locators 120 are used to locate the job (not shown) inside the die 100 and when the punches are 118 moved down by ramming force of the press, the die buttons 122 provide the punching support to the job during the operation. The die buttons 122 are mounted on the cavity 124, which is supported by Risers 126. This entire assembly is mounted on the bottom die shoe 110. Now, this same die arrangement without the top die shoe can be used for a variety of operations like bending, trimming and notching depending upon the required part and shape of the punch 118.

The characteristic feature of the present invention is the spring used in the die which can absorb ram forces in the range of 100 to 600 T. This spring is configured after detailed calculations and it also acts as a separator for the punch 118 and punch holder 112.

This involves unique die configuration, which can be used in various press tools operations performed for manufacturing sheet metal components by operations like blanking, punching, piercing, notching, flanging, bending etc.

TECHNICAL ADVANTAGES AND ECONOMIC SIGNIFICANCE

The topless die for sheet metal pressing operations and configured in accordance with the present invention has the following technical and economic advantages:
• At least one operator/day is saved using this die.

• Increases Productivity by almost 100%.

• Saving in the capital cost of improved die almost up to INR 4 lakh.

• Die-weight reduced by almost 30%.

• No top die means there is no load on counter balancer of press machine.

• Unsafe condition of scrap cutting by scissors eliminated.

• Zero burr present on the pressed component/part manufactured.
• In-house die making ensures die cost-reduction by almost 30%.

• Reduction in set-up time on press by almost 50% due to absence of top die.
• No die jamming due to the absence of top die, since no set-up required for it.

• Press parallelism doesn’t affect the die performance.

• Press flexibility is achieved, since the die can be mounted on any press.

• No load on the ram and its pinion, since top die is absent.

• No possibility of the cutter chipping-off.

• No operator’s fatigue.

• Die easy to maintain and inspect.

• Guide pins and guide bush not required, thus saving costs thereof.

• Poka-yoke mechanism eliminates product defects by avoiding operator’s mistakes.

• Consolidation of assets as less die parts required for making the same part.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept.

Therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

The description provided herein is purely by way of example and illustration. The various features and advantageous details are explained with reference to this non-limiting embodiment in the above description in accordance with the present invention.

The descriptions of well-known components and manufacturing and processing techniques are consciously omitted in this specification, so as not to unnecessarily obscure the specification.

It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, the skilled person will recognize that the embodiments herein can be practiced with modification within the spirit and scope of embodiments described herein.

Therefore, the skilled person can easily make innumerable changes, variations, modifications, alterations and/or integrations in terms of materials and method used to configure, manufacture and assemble various constituents, components, subassemblies, assemblies and in terms of the size, shapes, orientations and interrelationships without departing from the scope and spirit of the present invention.

The numerical values given of various physical parameters, dimensions and quantities are only approximate values and it is envisaged that the values higher or lower than the numerical value assigned to the physical parameters, dimensions and quantities fall within the scope of the disclosure unless there is a statement in the specification to the contrary.

Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising”, shall be understood to implies including a described element, integer or method step, or group of elements, integers or method steps, however, does not imply excluding any other element, integer or step, or group of elements, integers or method steps.

The use of the expression “a”, “at least” or “at least one” shall imply using one or more elements or ingredients or quantities, as used in the embodiment of the disclosure in order to achieve one or more of the intended objects or results of the present invention. ,CLAIMS:We claim:

1. A single-piece die (50, 100) for manufacturing sheet metal components from scrap sheet metal pieces by conducting a variety of pressing operations, such as cutting, trimming, blanking, punching, piercing, notching, flanging, bending depending on the shape of the sheet metal part to be manufactured.

2. A single-piece die for press operations to manufacture metal components, said die (50) comprises:

• a bottom-die plate (20) for mounting a plurality of cutting edges;

• a punch holder (12) configured with a column (14) to accommodate a spring (16) therein; and

• said punch holder (12) mounting a plurality of punches (18);

wherein pressed metal parts (30) are manufactured by cutting and trimming from a sheet metal piece by pressing said punches (18) on said punch holder (12) by moving down the press machine ram.

3. The single-piece die (50) as claimed in claim 2, wherein said die is configured as a topless die for pressing operations such as cutting or trimming of extra sheet metal from the metal part to be manufactured by means of said punches (18) on pressing against said punch holder (12).

4. The single-piece die (50) as claimed in claim 2, wherein said punch holder (12) is held on said column (14) by means of punch holder bolts (24).

5. The single-piece die (50) as claimed in claim 2, wherein said sheet metal piece is located in said die (50) by means of stoppers provided on said bottom die plate (20).

6. The single-piece die (50) as claimed in claim 2, wherein said spring is configured as a separator of said punch holder (12) from said punches (18).

7. The single-piece die (100) as claimed in claim 1, said die (100) comprises:

• a bottom-die plate (110) for mounting a punch holder (112);

• a punch holding pad (114) fitted with punches (118) mounted on said punch holder (112);

• said punch holder (112) mounting a plurality of punches (118);

• a plurality of locators (120) for locating the sheet metal piece for manufacturing the sheet metal part therefrom; and

• die buttons (122) mounted in a cavity (124) supported by risers (126);

wherein pressed metal parts (130) are manufactured from said sheet metal piece by pressing said punches (118) by moving down the press machine ram and guided springs (116) are provided for preventing lateral deflection thereof during the pressing operation by means of said punch holding pad (114).

8. The single-piece die (100) as claimed in claim 7, wherein said die is configured as a topless die for pressing operations of punching or piercing said sheet metal piece to form the metal part therefrom by moving down said punches (118) against said bottom die plate (110).

9. The single-piece die (100) as claimed in claim 7, wherein said spring (116) functions as a separator of punch holder (112) and punches (118).

10. The single-piece die (50, 100) as claimed in anyone of the claims 1 to 9, wherein said spring (16, 116) absorbs the press machine ram force, preferably in the range of about 100 to 600 tons.

Dated: this 29thday of September 2017. SANJAY KESHARWANI
APPLICANT’S PATENT AGENT