PILOT ASSEMBLY

- Standard Lifters, Inc.

A pilot assembly has an integral stripper and is coupled to a die member from the non-working side of the die member. The pilot tip precisely locates the stock strip in the metal forming die. The reciprocating ejector pins surrounding the pilot strip the stock from the pilot. The pilot assembly fits into an opening in the die member and can be secured by a single fastener that is received in the bottom of the pilot body of the pilot assembly.

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Description
BACKGROUND OF THE INVENTION

The present invention relates to metal forming dies and the like, and in particular to a pilot assembly with a self-contained stripper and associated method.

Metal forming dies, such as stamping dies and the like, are well known in the art. Progressive metal forming dies are unique, very sophisticated mechanisms which have multiple stations or progressions that are aligned longitudinally, and are designed to perform a specified operation at each station in a predetermined sequence to create a finished metal part. Progressive stamping dies are capable of forming complex metal parts at very high speeds, so as to minimize manufacturing costs.

Heretofore, the dies used in metal forming presses have typically been individually designed, one-of-a-kind assemblies for a particular part, with each of the various components being handcrafted and custom mounted or fitted in an associated die set, which is in turn positioned in a stamping press. Not only are the punches and the other forming tools in the die set individually designed and constructed, but the other parts of the die set, such as stock lifters, guides, end caps, keepers, cam returns, etc., are also custom designed, and installed in the die set. Current die making processes require carefully machined, precision holes and recesses in the die set for mounting the individual components, such that the same are quite labor intensive, and require substantial lead time to make, test, and set up in a stamping press. Consequently, such metal forming dies are very expensive to design, manufacture, and repair or modify.

Pilot assemblies, such as that disclosed in U.S. Pat. No. 4,342,214, are used for locating a work piece in successive forming stages of a machine, such as a punch press, where the work piece is progressively moved through the forming stages of the machine. The pilot assembly typically includes a pilot pin mounted to a movable die member of the machine for guiding entry into a previously formed hole in a work piece or in a companion die member as the die members are moved toward each other, the pin being axially retractable in its mounting in the event that it strikes an obstruction. The retraction movement of the pin may be controlled by a spring or a hydraulic mechanism which includes a hydraulic chamber formed behind the pin into which the pin moves to displace a hydraulic fluid therefrom.

While such prior pilot assemblies have proven generally successful, they are rather expensive and time consuming to construct and install in an associated die set. In addition, the pilot assemblies typically required a fastener from the working side of the die member and/or the use of a mounting block. Thus, a pilot assembly that does not need to have a fastener on the working side of the die member and that can provide a small footprint in the die member for a pilot with integral ejection would be advantageous and is described herein.

SUMMARY OF THE INVENTION

One aspect of the present invention is a modular pilot assembly for metal forming dies with a stock strip between at least two mutually converging and diverging die members. The modular pilot assembly has a pilot configured for operable support on an associated die member. The pilot has an outer end portion oriented toward the stock strip, an oppositely disposed inner end portion oriented away from the stock strip, and a medial portion disposed between the outer and inner ends. The medial portion has an outer end oriented toward the stock strip, an inner end oriented away from the stock strip, and at least one ejector pin aperture extending through the medial portion from the inner end to the outer end. The outer end portion extends from the outer end of the medial portion. The outer end portion includes a tapered surface. The inner end portion has an outer end oriented toward the stock strip that extends to the medial portion and an inner end oriented away from the stock strip and includes a retaining ring groove on an exterior surface of the inner end portion and a fastener aperture extending into the pilot from the inner end of the inner end portion. A spring member is received over the inner end portion of the pilot, with an outer end oriented toward the stock strip and an inner end oriented away from the stock strip. At least one ejector pin is slidingly received in the at least one ejector pin aperture in the medial portion. The pilot assembly has a spring retainer with an outer end oriented toward the stock strip and an inner end oriented away from the stock strip. The spring retainer also has a pilot aperture with an internal shoulder, and the spring retainer has an external shoulder. A retainer ring is positioned on the retainer ring groove and contacts the internal shoulder on the spring retainer. The outer end of the spring member contacts a surface of the at least one ejector pin. The inner end of the spring member contacts the external shoulder of the spring retainer. A fastener is received in the fastener aperture of the pilot to couple the pilot to a die member.

Another aspect of the present invention is a pilot assembly for metal forming dies. A pilot is configured for operable support on an associated die member, with an outer end portion, an oppositely disposed inner end portion, and a medial portion disposed between the outer and inner ends. The medial portion has an outer end, an inner end, and at least one ejector pin aperture extending through the medial portion from the inner end to the outer end. The outer end portion extends from the outer end of the medial portion. The outer end portion includes a tapered surface. The inner end portion has an outer end that extends to the medial portion and an oppositely disposed inner end portion. The inner end portion includes a retaining ring groove on an exterior surface of the inner end portion and a fastener aperture extends into the pilot from the inner end of the inner end portion. A spring member is received over the inner end portion of the pilot and has an outer end oriented toward the stock strip and an inner end oriented away from the stock strip. At least one ejector pin is slidingly received in the at least one ejector pin aperture in the medial portion. The at least one ejector pin includes a shoulder. The pilot assembly includes a spring retainer that has an outer end oriented toward the stock strip and an inner end oriented away from the stock strip, a pilot aperture with an internal shoulder, and an external shoulder. A retainer ring is positioned on the retainer ring groove that contacts the internal shoulder on the spring retainer. The outer end of the spring member contacts a surface of the at least one ejector pin. The inner end of the spring member contacts the external shoulder of the spring retainer. The shoulder on the at least one ejector pin contacts the inner end portion when the spring member is in an uncompressed position.

Yet another aspect of the present invention is a progressive metal forming die with a stock strip between at least two mutually converging and diverging die members and a pilot assembly with self-contained stripper for locating the stock strip in the metal forming die. A pilot is configured for operable support on one die member. The pilot has an outer end portion oriented toward the stock strip, an oppositely disposed inner end portion oriented away from the stock strip, and a medial portion disposed between the outer and inner ends. The medial portion has an outer end oriented toward the stock strip, an inner end oriented away from the stock strip, and at least one ejector pin aperture extending through the medial portion from the inner end to the outer end. The outer end portion extends from the outer end of the medial portion, the outer end portion including a tapered surface. The inner end portion has an outer end oriented toward the stock strip that extends to the medial portion and an inner end oriented away from the stock strip, and includes a retaining ring groove on an exterior surface of the inner end portion and a fastener aperture extending into the pilot from the inner end of the inner end portion. A spring member is received over the inner end portion of the pilot, and has an outer end oriented toward the stock strip and an inner end oriented away from the stock strip. At least one ejector pin is slidingly received in the at least one ejector pin aperture in the medial portion. The pilot assembly includes a spring retainer with an outer end oriented toward the stock strip and an inner end oriented away from the stock strip. The pilot assembly also has a pilot aperture with an internal shoulder, and the pilot assembly also has an external shoulder. A retainer ring is positioned on the retainer ring groove that contacts the internal shoulder on the spring retainer. A pilot aperture is formed in a die member. The pilot aperture includes a first shoulder that contacts the medial portion of the pilot, a second shoulder that contacts the spring retainer, and a fastener opening. The outer end of the spring member contacts a surface of the at least one ejector pin. The inner end of the spring member contacts the external shoulder of the spring retainer. A fastener is received in the fastener aperture of the pilot to couple the pilot to a die member.

These and other advantages of the invention will be further understood and appreciated by those skilled in the art by reference to the following written description, claims, and dependent drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a pilot assembly;

FIG. 2 is a front cross-sectional view of the pilot assembly shown in FIG. 1, taken along line II-II;

FIG. 3 is a front perspective view of the components of the pilot assembly shown in FIG. 1;

FIG. 4 is a partial front cross-sectional view of the pilot aperture in a die member;

FIG. 5 is a rotated partial front cross-sectional view of the pilot assembly shown in FIG. 1; and

FIG. 6 is a rotated partial front cross-sectional view of the pilot assembly shown in FIG. 1 installed in the pilot aperture shown in FIG. 4.

 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

For purposes of description herein, the terms “outer,” “inner,” “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in the attached drawings. However, it is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.

The reference numeral 2 currently designates a modular pilot assembly with a self-contained stripper embodying the present invention. As shown in FIG. 6, the pilot assembly 2 is particularly adapted for use in connection with a multi-stage progressive metal forming die having at least one die member 100. Typically, the multi-stage progressive metal forming die has two or more mutually converging and diverging die members. In the illustrated embodiment shown in FIG. 6, the pilot assembly 2 is coupled to a lower die member 100. However, the pilot assembly 2 can be coupled to an upper die member or other die member within the metal forming die.

The pilot assembly 2 includes a pilot body 4. The pilot body 4 includes an inner end portion 6 oriented away from the stock strip 300, an outer end portion 8 oriented toward the stock strip 300, and a medial portion 10 between the inner end portion 6 and outer end portion 8. The medial portion 10 has an inner end 13 oriented away from the stock strip 300 and an outer end 11 oriented toward the stock strip 300. At least one ejection pin aperture 20 extends through the medial portion 10 between the inner end 13 and outer end 11. The outer end portion 8 of the pilot 4 extends from the outer end 11 of the medial portion 10. The outer end portion 8 includes a tapered surface 15 that terminates in a tip 18. The inner end portion 6 has an outer end 23 that extends to the medial portion 10 and an inner end 21 that would be oriented away from the stock strip 300. The inner end portion 6 includes a retaining ring groove 72 on an exterior surface of the inner end portion 6. In the illustrated embodiment, the retaining ring groove 72 is located on the inner end 21 of the inner end portion 6. However, the retaining ring groove 72 could be positioned on other portions of the exterior surface of the inner end portion 6. A fastener aperture 80 extends into the pilot 4 from the inner end 21 of the inner end portion 6, as illustrated in FIGS. 2, 5, and 6.

A spring member 50 is received over the inner end portion 6 of the pilot body 4. The spring member 50 includes an outer end 54 oriented toward the stock strip 300 and an inner end 52 oriented away from the stock strip 300. In addition, the spring member 50 includes a cavity 56 that is received around the inner end portion 6 of the body 4.

The pilot assembly 2 includes one or more ejector pins 40. The ejector pins 40 include an outer end 42 oriented toward the stock strip 300 and an inner end 44 oriented away from the stock strip 300. The inner end 44 has a wider diameter than the outer end 42 creating a shoulder 46 on the ejector pins 40. In the illustrated embodiment, six ejector pins 40 are utilized in the pilot assembly 2. However, any number of ejector pins 40 can be utilized. In the illustrated embodiment, ejector pin openings 20 are radially spaced equidistant apart from each other on the medial portion 10 of the pilot body 4. However, the ejector pin openings 20 do not need to be equally spaced.

The pilot assembly 2 includes a spring retainer 60. The spring retainer 60 has an outer end 62 that is oriented toward the stock strip 300 and an inner end 64 that is oriented away from the stock strip 300. The inner end 64 has a wider diameter than the outer end 62, thus creating an exterior shoulder 66 on the spring retainer 60. The spring retainer 60 also includes a pilot opening 68. The pilot opening 68 has a wider section 69 forming an interior shoulder 65 on the spring retainer 60.

A retainer ring 70 is inserted in the retainer ring groove 72 on the inner end portion 6 of pilot body 4. The retainer ring 70 contacts the internal shoulder 65 of the spring retainer 60, as illustrated in FIGS. 2, 5, and 6. The outer end 54 of the spring member 50 contacts a surface 48 of the ejector pins 40. The inner end 52 of the spring member 50 contacts the external shoulder 66 of the spring retainer 60. Thus, the spring member 50 will bias the ejector pins 40 toward an extended position beyond the top surface 220 of the medial portion 10. The shoulder 46 on the ejector pins 40 contacts the lower surface 222 of the medial portion 10 of body 4 when the spring member 50 is not in a compressed state.

A fastener 200 with an option washer is coupled to the fastener aperture 80 to secure the pilot assembly 2 to the die member 100, as illustrated in FIG. 6. A pilot assembly opening 102 is formed into the die member 100. The pilot assembly opening 102 includes internal shoulders 110 and 108, as well as fastener opening 104. The centerline 106 of the pilot assembly opening 102 should align with the centerline of the fastener 200, as illustrated in FIG. 6. The head of the fastener 200 and/or optional washer should contact a surface of die member 100 to secure the pilot assembly 2 within the pilot assembly opening 102 in the die member 100.

The diameter 12 of the medial portion 10 is wider than the diameter 14 of the inner end portion 6. Similarly, the diameter 16 of the outer end portion 8 adjacent to the medial portion 10 should be smaller than the diameter 12 of the medial portion 10. The diameter 16 of that portion of the inner end portion 6 should be about the same diameter as the pilot opening 302 in the stock strip 300, as illustrated in FIG. 6. In operation, the tip 18 of the pilot assembly 2 is smaller than the pilot opening 302 in the stock strip 300. Given that a portion 19 of the outer end portion 8 of the pilot body 4 has the same (or slightly larger) diameter as the pilot opening 302 on the stock strip 300, the stock strip 300 is precisely located within the metal forming die by the pilot assembly 2. During the stamping process, the stock strip 300 will be compressed against the die member 100 as the die members converge. Once the opposite die member diverges, the spring member 50 will decompress and push the ejector pins 40 to strip the stock strip 300 away from the pilot assembly 2. The top surface 220 of the medial portion 10 can be flush with, or slightly recessed from, the adjacent surface of the die member 100, as illustrated in FIG. 6.

The pilot body 4 can be formed as a single piece or can include multiple pieces. The pilot body 4, the ejector pins 40, and the spring retainer 60 can be made from a hardened metal material. The pilot assembly 2 can be provided in a wide variety of sizes to accommodate many different metal forming die applications.

In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed herein. Such modifications are to be considered as included in the following claims, unless these claims by their language expressly state otherwise.

It will be understood by one having ordinary skill in the art that construction of the present disclosure and other components is not limited to any specific material. Other exemplary embodiments of the disclosure disclosed herein may be formed from a wide variety of materials, unless described otherwise herein.

For purposes of this disclosure, the term “coupled” or “operably coupled” (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated.

For purposes of this disclosure, the term “connected” or “operably connected” (in all of its forms, connect, connecting, connected, etc.) generally means that one component functions with respect to another component, even if there are other components located between the first and second component, and the term “operable” defines a functional relationship between components.

It is also important to note that the construction and arrangement of the elements of the present disclosure as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that, unless otherwise described, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating positions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations.

It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present disclosure. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting.

It is also to be understood that variations and modifications can be made on the aforementioned structures and methods without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.

Claims

1. A modular pilot assembly for metal forming dies having a stock strip between at least two mutually converging and diverging die members, comprising:

a pilot configured for operable support on an associated die member, having an outer end portion oriented toward the stock strip, an oppositely disposed inner end portion oriented away from the stock strip, and a medial portion disposed between said outer and inner ends; wherein said medial portion having an outer end oriented toward the stock strip, an inner end oriented away from the stock strip, and at least one ejector pin aperture extending through said medial portion from said inner end to said outer end; wherein said outer end portion extends from said outer end of said medial portion, said outer end portion including a tapered surface; wherein said inner end portion having an outer end oriented toward the stock strip that extends to said medial portion and an inner end oriented away from the stock strip, including a retaining ring groove on an exterior surface of said inner end portion and a fastener aperture extending into said pilot from the inner end of said inner end portion;
a spring member received over said inner end portion of said pilot, having an outer end oriented toward the stock strip and an inner end oriented away from the stock strip;
at least one ejector pin slidingly received in said at least one ejector pin aperture in said medial portion;
a spring retainer having an outer end oriented toward the stock strip and an inner end oriented away from the stock strip, a pilot aperture with an internal shoulder, and an external shoulder; and
a retainer ring positioned on said retainer ring groove that contacts said internal shoulder on said spring retainer;
wherein said outer end of said spring member contacts a surface of said at least one ejector pin;
wherein said inner end of said spring member contacts said external shoulder of said spring retainer; and
a fastener that is received in said fastener aperture of said pilot to couple said pilot to a die member.

2. The modular pilot assembly of claim 1, wherein said fastener aperture extends into said medial portion of said pilot.

3. The modular pilot assembly of claim 1, wherein said pilot is a single piece.

4. The modular pilot assembly of claim 1, wherein said medial portion has a first diameter and said inner end portion has a second diameter that is smaller than said first diameter.

5. The modular pilot assembly of claim 1, wherein said outer end portion includes an outer end oriented toward the stock strip and an inner end oriented away from the stock strip, said outer end including a pilot point and said inner end having a third diameter that is smaller than said first diameter.

6. The modular pilot assembly of claim 5, wherein said inner end of said outer end portion includes a section that is approximately the same diameter as a pilot hole in said stock strip.

7. The modular pilot assembly of claim 1, wherein said at least one ejector pin aperture is two or more ejector pin apertures, spaced radially equidistant from each other on said medial section.

8. A pilot assembly for metal forming dies, comprising:

a pilot configured for operable support on an associated die member, having an outer end portion, an oppositely disposed inner end portion, and a medial portion disposed between said outer and inner ends; wherein said medial portion having an outer end, an inner end, and at least one ejector pin aperture extending through said medial portion from said inner end to said outer end; wherein said outer end portion extends from said outer end of said medial portion, said outer end portion including a tapered surface; wherein said inner end portion has an outer end that extends to said medial portion and an oppositely disposed inner end portion, said inner end portion including a retaining ring groove on an exterior surface of said inner end portion and a fastener aperture extending into said pilot from the inner end of said inner end portion;
a spring member received over said inner end portion of said pilot, having an outer end oriented toward the stock strip and an inner end oriented away from the stock strip;
at least one ejector pin slidingly received in said at least one ejector pin aperture in said medial portion, said at least one exterior pin including a shoulder;
a spring retainer having an outer end oriented toward the stock strip and an inner end oriented away from the stock strip, a pilot aperture with an internal shoulder, and an external shoulder; and
a retainer ring positioned on said retainer ring groove that contacts said internal shoulder on said spring retainer;
wherein said outer end of said spring member contacts a surface of said at least one ejector pin;
wherein said inner end of said spring member contacts said external shoulder of said spring retainer; and
wherein said shoulder on said at least one ejector pin contacts said inner end portion when said spring member is in an uncompressed position.

9. The pilot assembly of claim 8, wherein said fastener aperture extends into said medial portion of said pilot.

10. The pilot assembly of claim 8, wherein said pilot is a single piece.

11. The pilot assembly of claim 8, wherein said medial portion has a first diameter and said inner end portion has a second diameter that is smaller than said first diameter.

12. The pilot assembly of claim 8, wherein said outer end portion includes an outer end and an inner end, said outer end including a pilot point and said inner end having a third diameter that is smaller than said first diameter.

13. The pilot assembly of claim 8, wherein said at least one ejector pin aperture is two or more ejector pin apertures, spaced radially equidistant from each other on said medial section.

14. A progressive metal forming die having a stock strip between at least two mutually converging and diverging die members, the improvement of a pilot assembly with self-contained stripper for locating the stock strip in the metal forming die, comprising:

a pilot configured for operable support on an associated die member, having an outer end portion oriented toward the stock strip, an oppositely disposed inner end portion oriented away from the stock strip, and a medial portion disposed between said outer and inner ends; wherein said medial portion having an outer end oriented toward the stock strip, an inner end oriented away from the stock strip, and at least one ejector pin aperture extending through said medial portion from said inner end to said outer end; wherein said outer end portion extends from said outer end of said medial portion, said outer end portion including a tapered surface; wherein said inner end portion having an outer end oriented toward the stock strip that extends to said medial portion and an inner end oriented away from the stock strip, including a retaining ring groove on an exterior surface of said inner end portion and a fastener aperture extending into said pilot from the inner end of said inner end portion;
a spring member received over said inner end portion of said pilot, having an outer end oriented toward the stock strip and an inner end oriented away from the stock strip;
at least one ejector pin slidingly received in said at least one ejector pin aperture in said medial portion;
a spring retainer having an outer end oriented toward the stock strip and an inner end oriented away from the stock strip, a pilot aperture with an internal shoulder, and an external shoulder;
a retainer ring positioned on said retainer ring groove that contacts said internal shoulder on said spring retainer;
a pilot aperture formed in a die member, said aperture including a first shoulder that contacts said medial portion of the pilot, a second shoulder that contacts said spring retainer, and a fastener opening;
wherein said outer end of said spring member contacts a surface of said at least one ejector pin;
wherein said inner end of said spring member contacts said external shoulder of said spring retainer; and
a fastener that is received in said fastener aperture of said pilot to couple said pilot to a die member.

15. The progressive metal forming die of claim 14, wherein said fastener aperture extends into said medial portion of said pilot.

16. The progressive metal forming die of claim 14, wherein said pilot is a single piece.

17. The progressive metal forming die of claim 14, wherein said medial portion has a first diameter and said inner end portion has a second diameter that is smaller than said first diameter.

18. The progressive metal forming die of claim 14, wherein said outer end portion includes an outer end oriented toward the stock strip and an inner end oriented away from the stock strip, said outer end including a pilot point and said inner end having a third diameter that is smaller than said first diameter.

19. The progressive metal forming die of claim 18, wherein said inner end of said outer end portion includes a section that is the same diameter as a pilot hole in said stock strip.

20. The progressive metal forming die of claim 14, wherein said at least one ejector pin aperture is two or more ejector pin apertures, spaced equidistant from each other on said medial section.

Patent History
Publication number: 20250065392
Type: Application
Filed: Aug 22, 2023
Publication Date: Feb 27, 2025
Applicant: Standard Lifters, Inc. (Grand Rapids, MI)
Inventors: SCOTT M. BREEN (Ada, MI), Joel T. Pyper (Holland, MI)
Application Number: 18/236,668
Classifications
International Classification: B21D 45/08 (20060101); B21D 43/06 (20060101); B21D 45/02 (20060101);