CA2050540A1 - Stripper cup insert and method making - Google Patents
Stripper cup insert and method makingInfo
- Publication number
- CA2050540A1 CA2050540A1 CA 2050540 CA2050540A CA2050540A1 CA 2050540 A1 CA2050540 A1 CA 2050540A1 CA 2050540 CA2050540 CA 2050540 CA 2050540 A CA2050540 A CA 2050540A CA 2050540 A1 CA2050540 A1 CA 2050540A1
- Authority
- CA
- Canada
- Prior art keywords
- stripper
- insert
- stripper insert
- recited
- plate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Landscapes
- Punching Or Piercing (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The present invention relates to a stripper insert to be used in a stamping operations such as with a ball-lock pierce punch.
The stripper insert of the present invention comprises a cylindrical sleeve having an outside diameter of uniform dimension having an end plate. The end plate extends outward a greater distance than the radius of the sleeve to form a peripheral flange which facilitates seating of the stripper insert within the stripper plate. The peripheral flange of the end plate is formed with at least one conical countersink contour adapted to removably secure the stripper insert within the stripper plate and allow limited movement during the stamping operation.
The present invention relates to a stripper insert to be used in a stamping operations such as with a ball-lock pierce punch.
The stripper insert of the present invention comprises a cylindrical sleeve having an outside diameter of uniform dimension having an end plate. The end plate extends outward a greater distance than the radius of the sleeve to form a peripheral flange which facilitates seating of the stripper insert within the stripper plate. The peripheral flange of the end plate is formed with at least one conical countersink contour adapted to removably secure the stripper insert within the stripper plate and allow limited movement during the stamping operation.
Description
2 0 5 ~
STRIPPER INSERT AND METHOD OF ~KING
BACRGROUND OF IHE INVENTION
The present invention relates to a stripper insert to be used in a stamping die operations such as with a ball-lock pierce punch.
Conventional inserts require that the stripper plate be counter milled to provide a pocket for the insertion of the stripper insert so that the outer surface of the stripper insert (the face) is flush with the face of the stripper plate. The window for a conventional stripper insert also requires machining to provide clearance through the stripper plate for the punch nib.
Conventional stripper inserts are held in position by screws which attach the stripper insert to the stripper plate. This arrangement requires custom manufacturing of conventional stripper inserts as stripper windows for different punches and different machines.
Prior art discloses several devices which serve to guide the punch or limit movement of the material on the stripper plate. The prior art devices known to me are typically manufactured from either plastic or metal. The following patents show variations of such prior art: (U.S. 4,246,815) Hugo, 1/27/81; (U.S. 3,973,454) Eller, 8/10/76; (U.S. 3,608,413) Borello, 9.28/71; (U.S. 3,496,818) Porter 2/24/70; (U.S. 3,213,729) Koch, 10/26/65; and (US 2,108,619) Smith, 7/3/36. The Eller and ~ugo references appear to be the clo6est prior art references of which the inventor i6 aware. Most of the other prior art devices provide a means of 6upporting and teadying the punch for special applications.
2 ~
M:~DDI.E~O~ & R~:~C;E3~
The Eller 3,973,454 reference shows a stripper insert formed of a plastic material with a metal retaining plate bolted in place to retain the stripper insert in position. This device Utilizes the punching tool to form an axial bore through the plastic component and the retainer. This type of assembly (having zero clearance between the punch and the stripper insert) is limited to use in operations which have limited vibrations, rocking, and bouncing motions associated with the stripper plate in a pressing operation. This type of assembly generally requires a costly guide system for the spring loaded stripper plate (such as a ball cage guide similar to the type used for high volume, expensive dies as with as carbide dies). An example of this type of die would be the fragile "quill" punches known by the industry as "IBM" type dies.
Another alternative method of using a zero clearance stripper insert such as that proposed by Eller would be to mount the insert in a fixed, bridge stripper. Otherwise, breakage would be likely to occur due to insufficient clearance between the punch and the insert.
Applicant's stripper insert is designed for limited movement to facilitate the rocking and bouncing motion of the stripper plate in the punching operations which would hamper the operation of a stripper insert such as is utilized by Eller. In nearly all cases, there is no need of providing expensive guides or ~pecial punching procedures for using the present invention. In addition, Eller's 2S device does not address the die designers problems asgociated with limited space. The extended ears of the Eller device consumes an MIDDLETO~ & R~:~ rLr~G~R ~ ~ ~
unnecessary amount of space, wherein the present invention is compact. Also, precise machining, milling, and fitting of at least one of the ears would be required to facilitate mounting of a stripper insert retainer due to the zero clearance required for the punch with respect to the stripper insert.
References such as the Hugo 4,246,815, Porter 3,496,818 Smith 2,108,619, and Borello 3,608,413 references are concerned with providing additional support to the punch during the manufacturing operation. The Hugo reference shows a punch bushing containing a recessed portion, wherein the recess is filled with a polymer to provide an annular insert which extends beyond the punch bushing.
Upon impact with the stripper plate the insert crowds around the nib of the punch and provides lateral support for the punch as the punch penetrates the workpiece. The Porter reference shows a stripper plate provided with a cylindrical guide bushing which is press-fitted into the stripper plate so as to remain immobile which is used to support fragile punches having intricate designs or shapes. The Smith reference uses a piercing die in which a cylindrical insert having overlapping portions in a dovetail telescopic engagement radially support the punch. As with the Porter device, the Smith device is used to support a fragile punch and limit its movement. Borello's patent employs a punching die ~rr~ngement in which the stripping die plate is provided with a guide member threadably secured therein, wherein the guide me~ber h~s a guide opening for the male punch member. This type of punching die arrangement is typically known as "fine bl~nking". In 2 ~
~51DDLl~JOX & R~rLINo~
"fine blanking" the upper and lower sections move toward and contact one another so that the opposing sections create a better shear edge than conventional press operations.
Other prior art references such as Xoch's 3,213,729 patent teaches the use of a "knockout" such as would be used with a "horizontal press", usually powered by hydraulics and used to punch and blank circular parts or other similar flat shapes. The annular shaped "knockout" is moved forward to strip an annular stamping from the punch and button die following a blanking and punching operation.
In some cases, stripper inserts which provide structural support to the punch point may represent a danger to a press operator in that a fragile punch may break due to lack of clearance in the stripper insert to counter all of the erratic motions of the stripper plate. Stripper inserts which emphasize zero clearance to support the punch may actually hinder the proper operation of the punch.
While these inventions serve to add structural support to the stripper plate and/or serve as guides for the punches; none of these prior art devices solve the problem of providing an inexpensive stripper insert which provides for a quick method of punch changeover and provides the clearance necessary for maintenance to the punch assembly. Only the present invention is designed for limited movement within the stripper plate assembly to accommodate the rocking, bouncing, vibrating, and ~hifting motions the stripper insert is subjected to durinq the punching operations.
MIDDLE~O~ & RE~-rrJ~a~ 2 ~,3 SUMHARY OF THE INVENTION
The stripper insert of the present invention is generally cylindrical in shape and hollow thereby forming a sleeve. The exterior wall of the sleeve is of uniform diameter. On one end of the sleeve is an end plate which extends outward past the diameter of the sleeve to form a peripheral flange which facilitates seating of the stripper insert within the stripper plate. The peripheral flange of the end plate is formed having at least one conical countersink contour adapted to removably secure the stripper insert within the stripper plate by a fastening means. ~he interior side walls of the sleeve have an inside diameter which taper near the end plate to form a shoulder designed to abut the punch on the downward stroke.
The cylindrical stripper insert is mounted to a stripper plate by drilling a hole through the stripper plate, reaming the hole in the stripper plate to accommodate the sleeve portion of the stripper insert via a slip-fit assembly, and counter-boring the reamed hole in the stripper plate to a depth that allows the flange to be seated within the stripper plate and the face of the stripper insert to fit flush with respect to the face of the stripper plate.
In the preferred embodiment, the stripper insert is held to the ~tripper plate with at least one flat head screw that is recessed within the flange of the ~tripper insert and tripper plate so that the head of the screws are contiguous with the outside ~dge of the flange. If more than one screw is uged, the ~crews are arranged in MIDDL~SO~ & RE~-~Lr~O~R 2 ~
an irregular, radial pattern to facilitate reassembly and proper alignment with the stripper plate and punch for one-way assembly.
The procedure for manufacturing and mounting a cylindrical stripper window to the stripper plate is less expensive and time consuming than the milling and mounting procedures currently used with conventional custom manufactured, shapes and sizes of stripper windows. Attachment of the stripper insert to the stripper plate using countersink screws permits quick assembly and disassembly of the stripper insert and also prevents movement of the stripper insert within the stripper plate. Removal of the stripper insert provides a means of access through the stripper plate. The ball holding the ball-lock pierce punch in place can be depressed allowing the punch to be removed or replaced while the die remains mounted in the punch press.
It is an objective of the present invention to provide a method of holding the sheet material that has been punched during retraction of the punch to prevent the creation of a formed deformation around the periphery of the punched opening in the material that has been punched.
Another objective of the present invention is to provide for a stripper insert which can be manufactured and sold at a fraction of the cost it now costs to manufacture conventional, custom manufnctured stripper inserts for stripper pl~tes due to its simple design and production from inexpensive material.
It is a further objective of the present invention to design a stripper insert which can be attached to the 6tripper plate 2 ~ 3 ~IDDI.E'rOX & R~:~ rLr~o~
assembly by a simple and economical method as compared to the expensive and time consuming procedure presently required to attach conventional, custom manufactured sizes and shapes of window inserts to the stripper plate. The conventional inserts require machining a clearance through the stripper plate then counter-milling a pocket to install the various shaped window inserts in the stripper plate. The present invention only requires a drilling, reaming, and counterboring procedure which is far less labor and time intensive than milling procedures.
It is a further objective to provide the present invention with a holding means to be used to locate the stripper insert in a staggered arrangement for one way, fool proof assembly with the stripper plate and to provide an economical method of accurately relocating the stripper insert after removal.
It is a further object of the present invention to provide an expedient and low cost method for domestic and international stamping die manufactures and users to remove or replace ball seated pierce punches or other ball seated, upper punch sections without having to remove the stamping die from the punch press.
~he present invention is so economical to manufacture and attach to stripper plate assemblies, as compared to the cost of machining conventional customized inserts, that die manufacturers and users can now employ the present invention to numerous ~pplications which previously where cost prohibitive due to the cost of tooling required to manufacture a small number o~ units or units requiring a unique design.
MIDDl.l~'rOX & R}!:t,''rI~Ol!:R 2 ~ 5 ~
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawings in which like numerals refer to like parts throughout the several views and wherein:
Figure 1 is a perspective view of the stripper insert.
Figure l(a) is a perspective yiew of the stripper disc.
Figure 2 is a cut-away side view of the stripper insert of figure l in use showing a punch piercing the insert and the inside tapered side walls of the sleeve forming a shoulder adjacent to the end plate.
Figure 3 is a side view of a punch and stripper insert of appropriate size.
Figure 4 is a cut-away side view of a bore drilled through a stripper plate.
Figure 5 is a cut-away side view of the bore of figure 4 reamed to accommodate the sleeve of the stripper insert of fig. l.
Figure 6 is a cut-away side view of the stripper plate showing the counterbore and reamed bore of the stripper plate prepared to accommodate the sleeve and flange of the stripper plate of figure l position in a slip-fit assembly.
Figure 7 is a side view of the stripper plate showing the drilled and threaded holes for removably securing the stripper insert within the ~tripper plate.
Figure 8 is a top view of the stripper plate showing the .~DDL~O~ & RE~LI~'C~
~ ~ jr~
irregular radial pattern of the threaded holes shown in figure 7.
Figure 9 i5 a cut-away side view of the stripper insert being held into position within the stripper plate using a clamp during the countersinking procedure.
Figure 10 is a cut-away side view showing the stripper insert and stripper plate after a countersink configuration has been machined into the stripper insert and stripper plate.
Figure 11 is a cut away side view of the stripper insert being secured within the stripper plate using a flat head socket screw mounted so that the head is uniformly flush with both the stripper insert and stripper plate.
Figure 12 is a top view of figure 11 showing the stripper insert held into position with the flat head socket screws.
Figure 13 is a cut-away side view of the upper die assembly of a punch press containing a punch, stripper insert, and stripper plate.
Figure 14 is a cut-away side view of the punch press showing the punch piercing a slug from the stripper insert.
Figure 15 is a perspective view of the stripper insert of figure 1 showing the conical countersink contours, and an opening formed in the end plate in the shape of the punch contour.
Figure 16 is a cut-away side view of the punch press wherein the ~tripper insert has been removed to facilitate insertion of a pro~e tool to depress the releasing ball and remove the punch.
Figure 17 is a cut-away side view of a single ~tripper insert used with two different types of punches.
2~ 3 DDLETo~ & R}~TLINO:E~R
Figure 18 is a cut-away view of a single stripper insert used with multiple punches.
SP~CIFICATION
The present invention comprises a stripper insert for use with a punch press and stamping die assembly including: a punch, and an upper die assembly having a stripper plate adapted to support stamping material disposed between the stripper plate and lower die plate. A perspective view of the stripper insert 10 is depicted - 10 in figure 1, showing the stripper insert 10 to be generally cylindrical in shape forming a sleeve 12 wherein the exterior wall of the sleeve 12 is of uniform diameter. On one end of the sleeve 12 is an end plate 14 which extends outward past the diameter of the sleeve 12 to form a peripheral flange 16 which facilitates seating of the stripper insert 10 within the stripper plate 18.
The peripheral flange 16 of the end plate 14 is formed having at least one conical countersink contour formed within the flange 16 to removably secure the stripper insert within the stripper plate 18 by a fastening means such as with a flat head socket screw. The interior side walls of the sleeve 12 have an inside diameter which tapers near the end plate 14 to form a ~houlder 20 as shown in figure 2 which abuts the shank 22 of the punch 24 during the downstroke of the punch 24. As shown in figure 1, the end plate 14 of the stripper insert 10 has been pierced with the punch poin~ 26 to form an opening near the center of the end pla~e 1~ adap~ed to provide clearance for the punch point 26 during the stamping 2~J~
MIDDI~TO~ & R~U~L~
operation. Another version of the stripper insert 10 uses the end plate 14 without the sleeve portion 12 as a type of stripper disc 74 as shown in figure l(a).
The stripper insert 10 as described in the preferred embodiment is manufactured from a piece of round bar stock and made of metal, preferably steel. Of course it is contemplated that other materials of construction may be used such as a synthetic polymer or a ceramic material; however, steel is strong, easy to work with, readily available, and inexpensive to use.
One method of fabricating a stripper insert 10 would be to weld a cylinder to a plate and machine the stripper insert 10 to the desired tolerances. Another method of manufacturing the stripper insert 10 would be to use a press to stamp a cap shaped stripper insert 10 from a single piece of metal and machine the rim to provide the desired flange support. This stamping method may also be used to produce a stripper disc 74, which is then machined to fit within the counterbore 32 of the stripper plate lB.
The method used to produce the present invention as described in the preferred embodiment is to machine one end of the round bar stock square to the rods axis. A bore is then drilled in the end of the bar stock opposite the face to create a sleeve 12. The inside shoulder 20 is formed by selecting a cutting tool having a ~ngled tip or angle motion. After drilling the bore, the round bar stock is turned in a lathe or screw machine to form the flange 16.
The bar stock is then cut off to the desired length to form the end plate 14. The stripper insert 10 may also be with a protective 2 ~
M~DDL~O~ & REU~Ln~'~B8 film or protective coating such as with a black oxide finish to resist rust and corrosion during handling and storage.
In order to use the stripper insert 10, an opening must be formed in the end plate 14 to accommodate the punch point 26 such as by piercing the end plate 14 and enlarging and machining the opening. The present invention employs a specific procedure for sizing the opening and adapting the stripper insert 10 to be attached to the stripper plate 18.
The correct size for the stripper insert 10 is selected based on the diameter of the pierce punch shank 24 as shown in figure 3.
Stripper inserts 10 can be manufactured to fit any size punch shank, standard U.S. sizes ranging from 1/8" to 1 3/4" in diameter or equivalent metric sizes are typical; however, stripper inserts 10 can be manufactured for any special 6ize regardless of the standard punch size criteria.
As illustrated in figure 4, a bore 28 is drilled through the stripper plate 18, wherein the drill bit has a diameter that is slightly less than the outside diameter of the sleeve 12 of the stripper insert 10.
The edge of the bore 28 in the stripper plate 18 as shown in figure 5 is reamed to produce a reamed bore 30 to accommodate a light slip fit asse~bly with the sleeve 12 of the stripper insert 10 .
The reamed bore 30 is then counter-bored to a depth that will allow the flnnge 16 ~f the end plate 14 of the str~pper insert 10 to fit within the counterbore 32 so that the stripper insert face 2~Jo~
~IDDL~TO~ & R~LI~B
34 is flush with the stripper plate face 36, or at least not more than .001 to .002" above the stripper plate face 36 as shown in figure 6.
As best shown in figures 8 and 13, the preferred embodiment of the present invention, the stripper insert 10 is removably secured in a movable fashion to the stripper plate 18 using three flat head socket screws 38 that are located in an irregular, radial pattern in order for the stripper insert.10 to have only one assembly location to facilitate quick change overs when using different shaped punches 24 and to facilitate exact location of the stripper insert 10 during the pressing operation. The shape of the stripper insert 10 and the irregular, radial screw pattern prevent the stripper insert form being installed backwards or misaligned. In order to secure the stripper insert 10 to the stripper plate 18, drill and tap threaded holes 40 into the stripper plate 18 in three places located in an irregular pattern around the edge of the counterbore 28 as shown in figure 7. Figure 8 shows the irregular pattern as viewed from the front of the stripper plate 18, wherein arc A is unequal to arc B, or arc C.
The stripper insert 10 is initially held in position within the stripper plate 18 by use of a clamp 42 threadably connected to one of the threaded holes 40 of the stripper plate 18 as shown in figure 9.
One of the two threaded holes 40 is then counter~ink so that both the stripper plate 18 and the ~tripper insert 10 can be uniformly machined for seating a flat head socket screw 38. Figure 2 ~
MIDDL~O~ & REt-TLr~-O~
10 shows the preferred embodiment of the present invention, wherein the major diameter of the conical countersink contour 44 machined into the stripper plate 18 and the end plate 14 of the stripper insert 10 is represented by segment E. The angle of the conical countersink contour 44 as shown by arc D in the preferred embodiment is approximately 82 degrees.
As shown in figure 10, a flat head socket screw 38 is removably installed in the threaded hole 40. Then remove the clamp 42 holding the stripper insert 10 is removed.
The two remaining threaded holes 40 are countersink while using the flat head socket screw 38 in the threaded hole 40 as a clamp to secure the stripper insert 10. Then the other flat head socket screws 38 are removably installed in the two remaining threaded holes 40 as illustrated in figures 11 and 12.
The stripper plate 18 is then mounted to the punch shoe 46 in the upper die assembly 48 as shown in figure 13, wherein the shoulder screw 45 holds the stripper plate 18 to the punch shoe 46 and provides preload on the compression springs 50. Figure 13 also shows the punch 24 in contact with the hardened back plate 52 and held in position by the pierce punch retainer 54. The face of the stripper insert 22 is should be flush with respect to the stripper plate face 36. It may be necessary to use a flat file to file the face of the stripper insert 22 in order to make it flush with the stripper plate face 36.
A major feature of ~he stripper insert 10 is the relatively thin wall thickness of the end plate 14. It is thin enough for a MIDDL~'rO~ & R~ ~L~o~ 2 ~
pierce punch to shear its contour through the end plate 14. The internal design of the stripper insert 10 utilizes a sleeve 12 which tapers near the end plate 14 to form a shoulder 20 and creating an angled or strut effect on the inside wall of the sleeve 12 to increase the structural strength of the sleeve 12. The shoulder 20 reduces the tendency of the thin end plate 14 to flex while performing the stripping action. In addition, the tapered shoulder 20 feature, permits the stripping insert 10 to utilize a sleeve 12 having a thinner wall thickness to support the end plate 14 during the stripping operation. The thin structure of the stripper insert 10 utilizing the tapered shoulder 20 is designed to maintain structural integrity while facilitating the design of a light weight and compact stripping insert 10. Of course where compactness of design is not an important consideration, the stripper insert 10 can be manufactured without the tapered shoulders 20 by using thicker sleeve 12 side walls for additional strength.
As illustrated in figure 14, the upper die assembly 48 is set into a pierce punch press 56 where it is power stroked to bring the upper die assembly 48 together with the lower ~ie section 58. The stripper insert face 34 must make full contact with the lower die section 58. The punch point 26 is used to pierce the end plate 14 of the stripper insert 10. The scrap slug 60 is punched from the end plate 14 to create an aperture 62 shaped with the ~ontour of the punch point 26. The scrap slug 60 falls through the hardened MIDDLE~O~j & ~ oE!a 2 B ~
die button 63, the lower die section 58, and the lower die holder 65.
The aperture 62 in the stripper insert 10 that allows the punch point 26 to go through must be machined (by filing, drilling, or milling) to provide clearance for the punch contour. Clearance between the punch point 26 and aperture 62 is required to facilitate the vibrating, rocking, bouncing, and shifting movement of the stripper plate 1~ when it is pressed against the work material 66. The aperture 62 through the end plate 14 of the stripper insert 10 must be increased enough to accommodate the motion of the punch through a guided or unguided stripper plate 18.
one method is to remove the pierced stripper insert 10 from the stripper plate 18 and use a marker to scribe a line 64 around the periphery of the aperture 62 to indicate the desired clearance for the punch point 26 as illustrated in figure 15. Using a powered and/or manual file tool, file the aperture 62 to increase the clearance indicated by the scribed line 64. The stripper insert 10 can then be reinstalled in the stripper plate 18 by matching the irregular pattern of the conical countersink contours 44 of the stripper insert 10 with the pattern of the threaded holes 40.
The present invention emphasizes the need for added clearance between the punch 24 and the aperture 62 of the stripper insert 10 due to the rocking, bouncing, vibrating, shifting ~otion of the spring prescured ~tripper plate 18. Typically, a 6pring MIDDL~O~; & R~1~LI~I~E1~
pressurized stripper plate 18 lowered during the press downstroke does not hold the material flat in such a way that the stripper insert 10 will support the punch 24 as it also descends to pierce a hole in the work material 66.
When the punch 24 strokes downward and the spring pressurized stripper plate 18 makes contact with the work material 66. The stripper plate 18 starts rocking and bouncing and shifting in horizontal directions that are nearly perpendicular to the vertical center line of the punch 24. Even when the pierce punch press 56 strokes upward and is at the top of the stroke position, the spring pressured stripper plate 18 still has a slight rocking and bouncing motion. This continuous, dynamic motion of a spring pressured stripper plate 18 is caused by several factors. Steel is highly elastic and it will bounce when it is thrust to a fixed surface.
The stripper plate 18 contact surface will never be perfectly parallel with respect to the work material 66. In fact, the work material 66 itself will never be absolutely uniform in thickness during the punching operation and it will be subject to slight deformation. Some part of the stripper plate 18 will engage the work material 66 before the punch 24 and start the rocking motion.
The largest contributors to the out of parallel problem that causes stripper plate 18 motion is the mechanical assembly variations, normal wear, and the accumulation of dirt on the equipment. It is virtually impossible to pre-load the compression ~prings 50 equally, as well as, position the compression springs 50 ~DDIæ:~O~ & RB~TTL~-aE~ 2 ~
geometrically sym~etrical so that the spring forces will be 6ubjected to equal compression and stabilize a stripper plate 18 perfectly. All of these factors contribute to the rocking and vibrating motion of a stripper plate 18.
There are three common devices used for guiding a stripper plate 18: a ball cage guide; a plain pin-bushing set mo~nted in similar fashion to the ball cage guide; and a customized assembly wherein the die manufacturer purchases a guide pin 68, such as a head type pierce punch blank, makes their own retainer, and purchases a drill bushing that the punch will ride in. Although the present invention will work equally well with any of these guide methods, it is also designed to work without any type of guide means. The stripper insert 10 can be installed in any die to correct improper stripper clearances and enhance die maintenance cost while correcting the stripping function to improve the part quality.
The compact design of the present invention is an important consideration contributing to the versatility of the stripper insert 10; therefore, the stripper insert 10 of the present invention can be miniaturized for each standard punch 24~
The stripper insert 10 provides a low cost means to remove ball-lock punches 24 from the punch retainer 54 without removing the entire stripper plate 18 or removing the entire upper die assembly 48 from the pierce punch press 56 for di6assembly. As ~llDDL~:'rO~ & R}SI'1~-G~}/ 2 ~
shown in figure 16, the stripper insert 10 of the present invention is designed and sized to provide clearance for a standard 1/8 "
diameter probe tool 70 to be used to change punches 24 so that the punch 24 can be removed or replaced while the upper die assembly 48 remains mounted in the punch press 60. Neither the stripper plate 18 nor the lower die section 58 need be removed. Simply unscrew the three, flat head socket screws 38 and remove the stripper insert lO. A probe tool 70 can be inserted through the opening in the stripper plate 18 and into the access hole 71 of the punch retainer 54 to contact the releasing ball lock 72. Depression of the releasing ball lock 72 releases the punch 24. The punch 24 and stripping insert 10 can then be replaced quickly to continue the pressing operations.
The stripper insert 10 design also permits a series or cluster of any combination of shearing or non-shearing punches 24 of different sizes or shapes to be used together utilizing a ~ingle stripper insert 10 to perform the stripping action as shown in figures 17 and 18.
The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrcm for modification will become obvious to those skilled in the firt upon reading this disclosure and may be made upon departing from the spirit of the invention ~nd scope of the appended claims.
STRIPPER INSERT AND METHOD OF ~KING
BACRGROUND OF IHE INVENTION
The present invention relates to a stripper insert to be used in a stamping die operations such as with a ball-lock pierce punch.
Conventional inserts require that the stripper plate be counter milled to provide a pocket for the insertion of the stripper insert so that the outer surface of the stripper insert (the face) is flush with the face of the stripper plate. The window for a conventional stripper insert also requires machining to provide clearance through the stripper plate for the punch nib.
Conventional stripper inserts are held in position by screws which attach the stripper insert to the stripper plate. This arrangement requires custom manufacturing of conventional stripper inserts as stripper windows for different punches and different machines.
Prior art discloses several devices which serve to guide the punch or limit movement of the material on the stripper plate. The prior art devices known to me are typically manufactured from either plastic or metal. The following patents show variations of such prior art: (U.S. 4,246,815) Hugo, 1/27/81; (U.S. 3,973,454) Eller, 8/10/76; (U.S. 3,608,413) Borello, 9.28/71; (U.S. 3,496,818) Porter 2/24/70; (U.S. 3,213,729) Koch, 10/26/65; and (US 2,108,619) Smith, 7/3/36. The Eller and ~ugo references appear to be the clo6est prior art references of which the inventor i6 aware. Most of the other prior art devices provide a means of 6upporting and teadying the punch for special applications.
2 ~
M:~DDI.E~O~ & R~:~C;E3~
The Eller 3,973,454 reference shows a stripper insert formed of a plastic material with a metal retaining plate bolted in place to retain the stripper insert in position. This device Utilizes the punching tool to form an axial bore through the plastic component and the retainer. This type of assembly (having zero clearance between the punch and the stripper insert) is limited to use in operations which have limited vibrations, rocking, and bouncing motions associated with the stripper plate in a pressing operation. This type of assembly generally requires a costly guide system for the spring loaded stripper plate (such as a ball cage guide similar to the type used for high volume, expensive dies as with as carbide dies). An example of this type of die would be the fragile "quill" punches known by the industry as "IBM" type dies.
Another alternative method of using a zero clearance stripper insert such as that proposed by Eller would be to mount the insert in a fixed, bridge stripper. Otherwise, breakage would be likely to occur due to insufficient clearance between the punch and the insert.
Applicant's stripper insert is designed for limited movement to facilitate the rocking and bouncing motion of the stripper plate in the punching operations which would hamper the operation of a stripper insert such as is utilized by Eller. In nearly all cases, there is no need of providing expensive guides or ~pecial punching procedures for using the present invention. In addition, Eller's 2S device does not address the die designers problems asgociated with limited space. The extended ears of the Eller device consumes an MIDDLETO~ & R~:~ rLr~G~R ~ ~ ~
unnecessary amount of space, wherein the present invention is compact. Also, precise machining, milling, and fitting of at least one of the ears would be required to facilitate mounting of a stripper insert retainer due to the zero clearance required for the punch with respect to the stripper insert.
References such as the Hugo 4,246,815, Porter 3,496,818 Smith 2,108,619, and Borello 3,608,413 references are concerned with providing additional support to the punch during the manufacturing operation. The Hugo reference shows a punch bushing containing a recessed portion, wherein the recess is filled with a polymer to provide an annular insert which extends beyond the punch bushing.
Upon impact with the stripper plate the insert crowds around the nib of the punch and provides lateral support for the punch as the punch penetrates the workpiece. The Porter reference shows a stripper plate provided with a cylindrical guide bushing which is press-fitted into the stripper plate so as to remain immobile which is used to support fragile punches having intricate designs or shapes. The Smith reference uses a piercing die in which a cylindrical insert having overlapping portions in a dovetail telescopic engagement radially support the punch. As with the Porter device, the Smith device is used to support a fragile punch and limit its movement. Borello's patent employs a punching die ~rr~ngement in which the stripping die plate is provided with a guide member threadably secured therein, wherein the guide me~ber h~s a guide opening for the male punch member. This type of punching die arrangement is typically known as "fine bl~nking". In 2 ~
~51DDLl~JOX & R~rLINo~
"fine blanking" the upper and lower sections move toward and contact one another so that the opposing sections create a better shear edge than conventional press operations.
Other prior art references such as Xoch's 3,213,729 patent teaches the use of a "knockout" such as would be used with a "horizontal press", usually powered by hydraulics and used to punch and blank circular parts or other similar flat shapes. The annular shaped "knockout" is moved forward to strip an annular stamping from the punch and button die following a blanking and punching operation.
In some cases, stripper inserts which provide structural support to the punch point may represent a danger to a press operator in that a fragile punch may break due to lack of clearance in the stripper insert to counter all of the erratic motions of the stripper plate. Stripper inserts which emphasize zero clearance to support the punch may actually hinder the proper operation of the punch.
While these inventions serve to add structural support to the stripper plate and/or serve as guides for the punches; none of these prior art devices solve the problem of providing an inexpensive stripper insert which provides for a quick method of punch changeover and provides the clearance necessary for maintenance to the punch assembly. Only the present invention is designed for limited movement within the stripper plate assembly to accommodate the rocking, bouncing, vibrating, and ~hifting motions the stripper insert is subjected to durinq the punching operations.
MIDDLE~O~ & RE~-rrJ~a~ 2 ~,3 SUMHARY OF THE INVENTION
The stripper insert of the present invention is generally cylindrical in shape and hollow thereby forming a sleeve. The exterior wall of the sleeve is of uniform diameter. On one end of the sleeve is an end plate which extends outward past the diameter of the sleeve to form a peripheral flange which facilitates seating of the stripper insert within the stripper plate. The peripheral flange of the end plate is formed having at least one conical countersink contour adapted to removably secure the stripper insert within the stripper plate by a fastening means. ~he interior side walls of the sleeve have an inside diameter which taper near the end plate to form a shoulder designed to abut the punch on the downward stroke.
The cylindrical stripper insert is mounted to a stripper plate by drilling a hole through the stripper plate, reaming the hole in the stripper plate to accommodate the sleeve portion of the stripper insert via a slip-fit assembly, and counter-boring the reamed hole in the stripper plate to a depth that allows the flange to be seated within the stripper plate and the face of the stripper insert to fit flush with respect to the face of the stripper plate.
In the preferred embodiment, the stripper insert is held to the ~tripper plate with at least one flat head screw that is recessed within the flange of the ~tripper insert and tripper plate so that the head of the screws are contiguous with the outside ~dge of the flange. If more than one screw is uged, the ~crews are arranged in MIDDL~SO~ & RE~-~Lr~O~R 2 ~
an irregular, radial pattern to facilitate reassembly and proper alignment with the stripper plate and punch for one-way assembly.
The procedure for manufacturing and mounting a cylindrical stripper window to the stripper plate is less expensive and time consuming than the milling and mounting procedures currently used with conventional custom manufactured, shapes and sizes of stripper windows. Attachment of the stripper insert to the stripper plate using countersink screws permits quick assembly and disassembly of the stripper insert and also prevents movement of the stripper insert within the stripper plate. Removal of the stripper insert provides a means of access through the stripper plate. The ball holding the ball-lock pierce punch in place can be depressed allowing the punch to be removed or replaced while the die remains mounted in the punch press.
It is an objective of the present invention to provide a method of holding the sheet material that has been punched during retraction of the punch to prevent the creation of a formed deformation around the periphery of the punched opening in the material that has been punched.
Another objective of the present invention is to provide for a stripper insert which can be manufactured and sold at a fraction of the cost it now costs to manufacture conventional, custom manufnctured stripper inserts for stripper pl~tes due to its simple design and production from inexpensive material.
It is a further objective of the present invention to design a stripper insert which can be attached to the 6tripper plate 2 ~ 3 ~IDDI.E'rOX & R~:~ rLr~o~
assembly by a simple and economical method as compared to the expensive and time consuming procedure presently required to attach conventional, custom manufactured sizes and shapes of window inserts to the stripper plate. The conventional inserts require machining a clearance through the stripper plate then counter-milling a pocket to install the various shaped window inserts in the stripper plate. The present invention only requires a drilling, reaming, and counterboring procedure which is far less labor and time intensive than milling procedures.
It is a further objective to provide the present invention with a holding means to be used to locate the stripper insert in a staggered arrangement for one way, fool proof assembly with the stripper plate and to provide an economical method of accurately relocating the stripper insert after removal.
It is a further object of the present invention to provide an expedient and low cost method for domestic and international stamping die manufactures and users to remove or replace ball seated pierce punches or other ball seated, upper punch sections without having to remove the stamping die from the punch press.
~he present invention is so economical to manufacture and attach to stripper plate assemblies, as compared to the cost of machining conventional customized inserts, that die manufacturers and users can now employ the present invention to numerous ~pplications which previously where cost prohibitive due to the cost of tooling required to manufacture a small number o~ units or units requiring a unique design.
MIDDl.l~'rOX & R}!:t,''rI~Ol!:R 2 ~ 5 ~
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawings in which like numerals refer to like parts throughout the several views and wherein:
Figure 1 is a perspective view of the stripper insert.
Figure l(a) is a perspective yiew of the stripper disc.
Figure 2 is a cut-away side view of the stripper insert of figure l in use showing a punch piercing the insert and the inside tapered side walls of the sleeve forming a shoulder adjacent to the end plate.
Figure 3 is a side view of a punch and stripper insert of appropriate size.
Figure 4 is a cut-away side view of a bore drilled through a stripper plate.
Figure 5 is a cut-away side view of the bore of figure 4 reamed to accommodate the sleeve of the stripper insert of fig. l.
Figure 6 is a cut-away side view of the stripper plate showing the counterbore and reamed bore of the stripper plate prepared to accommodate the sleeve and flange of the stripper plate of figure l position in a slip-fit assembly.
Figure 7 is a side view of the stripper plate showing the drilled and threaded holes for removably securing the stripper insert within the ~tripper plate.
Figure 8 is a top view of the stripper plate showing the .~DDL~O~ & RE~LI~'C~
~ ~ jr~
irregular radial pattern of the threaded holes shown in figure 7.
Figure 9 i5 a cut-away side view of the stripper insert being held into position within the stripper plate using a clamp during the countersinking procedure.
Figure 10 is a cut-away side view showing the stripper insert and stripper plate after a countersink configuration has been machined into the stripper insert and stripper plate.
Figure 11 is a cut away side view of the stripper insert being secured within the stripper plate using a flat head socket screw mounted so that the head is uniformly flush with both the stripper insert and stripper plate.
Figure 12 is a top view of figure 11 showing the stripper insert held into position with the flat head socket screws.
Figure 13 is a cut-away side view of the upper die assembly of a punch press containing a punch, stripper insert, and stripper plate.
Figure 14 is a cut-away side view of the punch press showing the punch piercing a slug from the stripper insert.
Figure 15 is a perspective view of the stripper insert of figure 1 showing the conical countersink contours, and an opening formed in the end plate in the shape of the punch contour.
Figure 16 is a cut-away side view of the punch press wherein the ~tripper insert has been removed to facilitate insertion of a pro~e tool to depress the releasing ball and remove the punch.
Figure 17 is a cut-away side view of a single ~tripper insert used with two different types of punches.
2~ 3 DDLETo~ & R}~TLINO:E~R
Figure 18 is a cut-away view of a single stripper insert used with multiple punches.
SP~CIFICATION
The present invention comprises a stripper insert for use with a punch press and stamping die assembly including: a punch, and an upper die assembly having a stripper plate adapted to support stamping material disposed between the stripper plate and lower die plate. A perspective view of the stripper insert 10 is depicted - 10 in figure 1, showing the stripper insert 10 to be generally cylindrical in shape forming a sleeve 12 wherein the exterior wall of the sleeve 12 is of uniform diameter. On one end of the sleeve 12 is an end plate 14 which extends outward past the diameter of the sleeve 12 to form a peripheral flange 16 which facilitates seating of the stripper insert 10 within the stripper plate 18.
The peripheral flange 16 of the end plate 14 is formed having at least one conical countersink contour formed within the flange 16 to removably secure the stripper insert within the stripper plate 18 by a fastening means such as with a flat head socket screw. The interior side walls of the sleeve 12 have an inside diameter which tapers near the end plate 14 to form a ~houlder 20 as shown in figure 2 which abuts the shank 22 of the punch 24 during the downstroke of the punch 24. As shown in figure 1, the end plate 14 of the stripper insert 10 has been pierced with the punch poin~ 26 to form an opening near the center of the end pla~e 1~ adap~ed to provide clearance for the punch point 26 during the stamping 2~J~
MIDDI~TO~ & R~U~L~
operation. Another version of the stripper insert 10 uses the end plate 14 without the sleeve portion 12 as a type of stripper disc 74 as shown in figure l(a).
The stripper insert 10 as described in the preferred embodiment is manufactured from a piece of round bar stock and made of metal, preferably steel. Of course it is contemplated that other materials of construction may be used such as a synthetic polymer or a ceramic material; however, steel is strong, easy to work with, readily available, and inexpensive to use.
One method of fabricating a stripper insert 10 would be to weld a cylinder to a plate and machine the stripper insert 10 to the desired tolerances. Another method of manufacturing the stripper insert 10 would be to use a press to stamp a cap shaped stripper insert 10 from a single piece of metal and machine the rim to provide the desired flange support. This stamping method may also be used to produce a stripper disc 74, which is then machined to fit within the counterbore 32 of the stripper plate lB.
The method used to produce the present invention as described in the preferred embodiment is to machine one end of the round bar stock square to the rods axis. A bore is then drilled in the end of the bar stock opposite the face to create a sleeve 12. The inside shoulder 20 is formed by selecting a cutting tool having a ~ngled tip or angle motion. After drilling the bore, the round bar stock is turned in a lathe or screw machine to form the flange 16.
The bar stock is then cut off to the desired length to form the end plate 14. The stripper insert 10 may also be with a protective 2 ~
M~DDL~O~ & REU~Ln~'~B8 film or protective coating such as with a black oxide finish to resist rust and corrosion during handling and storage.
In order to use the stripper insert 10, an opening must be formed in the end plate 14 to accommodate the punch point 26 such as by piercing the end plate 14 and enlarging and machining the opening. The present invention employs a specific procedure for sizing the opening and adapting the stripper insert 10 to be attached to the stripper plate 18.
The correct size for the stripper insert 10 is selected based on the diameter of the pierce punch shank 24 as shown in figure 3.
Stripper inserts 10 can be manufactured to fit any size punch shank, standard U.S. sizes ranging from 1/8" to 1 3/4" in diameter or equivalent metric sizes are typical; however, stripper inserts 10 can be manufactured for any special 6ize regardless of the standard punch size criteria.
As illustrated in figure 4, a bore 28 is drilled through the stripper plate 18, wherein the drill bit has a diameter that is slightly less than the outside diameter of the sleeve 12 of the stripper insert 10.
The edge of the bore 28 in the stripper plate 18 as shown in figure 5 is reamed to produce a reamed bore 30 to accommodate a light slip fit asse~bly with the sleeve 12 of the stripper insert 10 .
The reamed bore 30 is then counter-bored to a depth that will allow the flnnge 16 ~f the end plate 14 of the str~pper insert 10 to fit within the counterbore 32 so that the stripper insert face 2~Jo~
~IDDL~TO~ & R~LI~B
34 is flush with the stripper plate face 36, or at least not more than .001 to .002" above the stripper plate face 36 as shown in figure 6.
As best shown in figures 8 and 13, the preferred embodiment of the present invention, the stripper insert 10 is removably secured in a movable fashion to the stripper plate 18 using three flat head socket screws 38 that are located in an irregular, radial pattern in order for the stripper insert.10 to have only one assembly location to facilitate quick change overs when using different shaped punches 24 and to facilitate exact location of the stripper insert 10 during the pressing operation. The shape of the stripper insert 10 and the irregular, radial screw pattern prevent the stripper insert form being installed backwards or misaligned. In order to secure the stripper insert 10 to the stripper plate 18, drill and tap threaded holes 40 into the stripper plate 18 in three places located in an irregular pattern around the edge of the counterbore 28 as shown in figure 7. Figure 8 shows the irregular pattern as viewed from the front of the stripper plate 18, wherein arc A is unequal to arc B, or arc C.
The stripper insert 10 is initially held in position within the stripper plate 18 by use of a clamp 42 threadably connected to one of the threaded holes 40 of the stripper plate 18 as shown in figure 9.
One of the two threaded holes 40 is then counter~ink so that both the stripper plate 18 and the ~tripper insert 10 can be uniformly machined for seating a flat head socket screw 38. Figure 2 ~
MIDDL~O~ & REt-TLr~-O~
10 shows the preferred embodiment of the present invention, wherein the major diameter of the conical countersink contour 44 machined into the stripper plate 18 and the end plate 14 of the stripper insert 10 is represented by segment E. The angle of the conical countersink contour 44 as shown by arc D in the preferred embodiment is approximately 82 degrees.
As shown in figure 10, a flat head socket screw 38 is removably installed in the threaded hole 40. Then remove the clamp 42 holding the stripper insert 10 is removed.
The two remaining threaded holes 40 are countersink while using the flat head socket screw 38 in the threaded hole 40 as a clamp to secure the stripper insert 10. Then the other flat head socket screws 38 are removably installed in the two remaining threaded holes 40 as illustrated in figures 11 and 12.
The stripper plate 18 is then mounted to the punch shoe 46 in the upper die assembly 48 as shown in figure 13, wherein the shoulder screw 45 holds the stripper plate 18 to the punch shoe 46 and provides preload on the compression springs 50. Figure 13 also shows the punch 24 in contact with the hardened back plate 52 and held in position by the pierce punch retainer 54. The face of the stripper insert 22 is should be flush with respect to the stripper plate face 36. It may be necessary to use a flat file to file the face of the stripper insert 22 in order to make it flush with the stripper plate face 36.
A major feature of ~he stripper insert 10 is the relatively thin wall thickness of the end plate 14. It is thin enough for a MIDDL~'rO~ & R~ ~L~o~ 2 ~
pierce punch to shear its contour through the end plate 14. The internal design of the stripper insert 10 utilizes a sleeve 12 which tapers near the end plate 14 to form a shoulder 20 and creating an angled or strut effect on the inside wall of the sleeve 12 to increase the structural strength of the sleeve 12. The shoulder 20 reduces the tendency of the thin end plate 14 to flex while performing the stripping action. In addition, the tapered shoulder 20 feature, permits the stripping insert 10 to utilize a sleeve 12 having a thinner wall thickness to support the end plate 14 during the stripping operation. The thin structure of the stripper insert 10 utilizing the tapered shoulder 20 is designed to maintain structural integrity while facilitating the design of a light weight and compact stripping insert 10. Of course where compactness of design is not an important consideration, the stripper insert 10 can be manufactured without the tapered shoulders 20 by using thicker sleeve 12 side walls for additional strength.
As illustrated in figure 14, the upper die assembly 48 is set into a pierce punch press 56 where it is power stroked to bring the upper die assembly 48 together with the lower ~ie section 58. The stripper insert face 34 must make full contact with the lower die section 58. The punch point 26 is used to pierce the end plate 14 of the stripper insert 10. The scrap slug 60 is punched from the end plate 14 to create an aperture 62 shaped with the ~ontour of the punch point 26. The scrap slug 60 falls through the hardened MIDDLE~O~j & ~ oE!a 2 B ~
die button 63, the lower die section 58, and the lower die holder 65.
The aperture 62 in the stripper insert 10 that allows the punch point 26 to go through must be machined (by filing, drilling, or milling) to provide clearance for the punch contour. Clearance between the punch point 26 and aperture 62 is required to facilitate the vibrating, rocking, bouncing, and shifting movement of the stripper plate 1~ when it is pressed against the work material 66. The aperture 62 through the end plate 14 of the stripper insert 10 must be increased enough to accommodate the motion of the punch through a guided or unguided stripper plate 18.
one method is to remove the pierced stripper insert 10 from the stripper plate 18 and use a marker to scribe a line 64 around the periphery of the aperture 62 to indicate the desired clearance for the punch point 26 as illustrated in figure 15. Using a powered and/or manual file tool, file the aperture 62 to increase the clearance indicated by the scribed line 64. The stripper insert 10 can then be reinstalled in the stripper plate 18 by matching the irregular pattern of the conical countersink contours 44 of the stripper insert 10 with the pattern of the threaded holes 40.
The present invention emphasizes the need for added clearance between the punch 24 and the aperture 62 of the stripper insert 10 due to the rocking, bouncing, vibrating, shifting ~otion of the spring prescured ~tripper plate 18. Typically, a 6pring MIDDL~O~; & R~1~LI~I~E1~
pressurized stripper plate 18 lowered during the press downstroke does not hold the material flat in such a way that the stripper insert 10 will support the punch 24 as it also descends to pierce a hole in the work material 66.
When the punch 24 strokes downward and the spring pressurized stripper plate 18 makes contact with the work material 66. The stripper plate 18 starts rocking and bouncing and shifting in horizontal directions that are nearly perpendicular to the vertical center line of the punch 24. Even when the pierce punch press 56 strokes upward and is at the top of the stroke position, the spring pressured stripper plate 18 still has a slight rocking and bouncing motion. This continuous, dynamic motion of a spring pressured stripper plate 18 is caused by several factors. Steel is highly elastic and it will bounce when it is thrust to a fixed surface.
The stripper plate 18 contact surface will never be perfectly parallel with respect to the work material 66. In fact, the work material 66 itself will never be absolutely uniform in thickness during the punching operation and it will be subject to slight deformation. Some part of the stripper plate 18 will engage the work material 66 before the punch 24 and start the rocking motion.
The largest contributors to the out of parallel problem that causes stripper plate 18 motion is the mechanical assembly variations, normal wear, and the accumulation of dirt on the equipment. It is virtually impossible to pre-load the compression ~prings 50 equally, as well as, position the compression springs 50 ~DDIæ:~O~ & RB~TTL~-aE~ 2 ~
geometrically sym~etrical so that the spring forces will be 6ubjected to equal compression and stabilize a stripper plate 18 perfectly. All of these factors contribute to the rocking and vibrating motion of a stripper plate 18.
There are three common devices used for guiding a stripper plate 18: a ball cage guide; a plain pin-bushing set mo~nted in similar fashion to the ball cage guide; and a customized assembly wherein the die manufacturer purchases a guide pin 68, such as a head type pierce punch blank, makes their own retainer, and purchases a drill bushing that the punch will ride in. Although the present invention will work equally well with any of these guide methods, it is also designed to work without any type of guide means. The stripper insert 10 can be installed in any die to correct improper stripper clearances and enhance die maintenance cost while correcting the stripping function to improve the part quality.
The compact design of the present invention is an important consideration contributing to the versatility of the stripper insert 10; therefore, the stripper insert 10 of the present invention can be miniaturized for each standard punch 24~
The stripper insert 10 provides a low cost means to remove ball-lock punches 24 from the punch retainer 54 without removing the entire stripper plate 18 or removing the entire upper die assembly 48 from the pierce punch press 56 for di6assembly. As ~llDDL~:'rO~ & R}SI'1~-G~}/ 2 ~
shown in figure 16, the stripper insert 10 of the present invention is designed and sized to provide clearance for a standard 1/8 "
diameter probe tool 70 to be used to change punches 24 so that the punch 24 can be removed or replaced while the upper die assembly 48 remains mounted in the punch press 60. Neither the stripper plate 18 nor the lower die section 58 need be removed. Simply unscrew the three, flat head socket screws 38 and remove the stripper insert lO. A probe tool 70 can be inserted through the opening in the stripper plate 18 and into the access hole 71 of the punch retainer 54 to contact the releasing ball lock 72. Depression of the releasing ball lock 72 releases the punch 24. The punch 24 and stripping insert 10 can then be replaced quickly to continue the pressing operations.
The stripper insert 10 design also permits a series or cluster of any combination of shearing or non-shearing punches 24 of different sizes or shapes to be used together utilizing a ~ingle stripper insert 10 to perform the stripping action as shown in figures 17 and 18.
The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrcm for modification will become obvious to those skilled in the firt upon reading this disclosure and may be made upon departing from the spirit of the invention ~nd scope of the appended claims.
Claims (13)
1. A stripper insert for use with a punch press and stamping die assembly, including a punch and an upper die assembly holding said punch, a stripper plate adapted to support stamping material disposed between said stripper plate, and a lower die plate, comprising:
an upwardly extending cylindrical sleeve portion having an outside diameter of uniform dimension and a bottom end plate attached to said sleeve extending outward a distance greater than the radius of said sleeve forming a peripheral flange around said sleeve.
an upwardly extending cylindrical sleeve portion having an outside diameter of uniform dimension and a bottom end plate attached to said sleeve extending outward a distance greater than the radius of said sleeve forming a peripheral flange around said sleeve.
2. The stripper insert as recited in claim 1, wherein said end plate is formed having an aperture near center with respect to said sleeve, adapted to receive said punch.
3. The stripper insert as recited in claim 1, wherein said end plate having an aperture is formed by placing a stripper insert in alignment within said punch and die assembly and piercing said end plate with the punch and machining the edges of said end plate aperture by any combination of machining such as drilling, milling, filing, laser burning or by an electrical discharge machine to achieve the desired clearance between said punch and said stripper insert.
4. The stripper insert as recited in claim 1, including a recessed holding means to removably secure said stripper insert in a fixed manner within said stripper plate.
MIDDLETON & REUTLINGER
MIDDLETON & REUTLINGER
5. The stripper insert as recited in claim 4, wherein said holding means is a flat head socket screw.
6. The stripper insert as recited in claim 4, wherein said holding means is a ball or wedge lock disposed on said stripper insert which extends into a recess within said stripper plate.
7. The stripper insert as recited in claim 4, wherein said holding means is a recess formed within said stripper insert to accommodate said ball or wedge lock extending from said stripper plate.
8. The stripper insert as recited in claim 1, wherein said peripheral flange is formed having at least one conical countersink contour to accommodate a recessed holding means in contact with said stripper plate.
9. The stripper insert as recited in claim 1, wherein said peripheral flange is formed having at least two conical countersink contours spaced in an irregular pattern to facilitate repositioning of said stripper insert during assembly and disassembly.
10. The stripper insert as recited in claim 1, wherein said peripheral flange is formed having a recess to accommodate repositioning of said stripper insert during assembly and disassembly.
11. The stripper insert as recited in claim 1, wherein said peripheral flange is formed having projections such as tabs to facilitate repositioning of said stripper insert during assembly and disassembly.
MIDDLETON & REUTLINGER
MIDDLETON & REUTLINGER
12. The stripper insert as recited in claim 1, wherein said end plate is of uniform thickness.
13. The stripper insert as recited in claim 1, wherein said end plate is thin enough in the center area to accommodate piercing. 14. The stripper insert as recited in claim 1, wherein said end plate is thicker in the center than the outer edge adjacent said sleeve.
15. The stripper insert as recited in claim 1, wherein said stripper insert is manufactured from metal.
16. The stripper insert as recited in claim 1, wherein said stripper insert is composed of a synthetic polymer.
17. The stripper insert as recited in claim 1, wherein said stripper insert is composed of a ceramic material.
18. The stripper insert as recited in claim 1, wherein said stripper insert is coated with a protective coating.
19. The protective coating recited in claim 18, wherein said protective coating is iron oxide.
20. The protective coating recited in claim 18, wherein said protective coating is black oxide.
21. The stripper insert as recite in claim 1, wherein said stripper insert is coated with a protective film.
24. A stripper insert for use with a punch press and stamping die assembly, including a punch and an upper die assembly holding said punch, a stripper plate adapted to support stamping material disposed between said stripper plate, and a lower die plate comprising:
MIDDLETON & REUTLINGER
an upwardly extending cylindrical sleeve portion having an outside diameter of uniform dimension and a bottom end plate attached to said sleeve extending outward a distance greater than the radius of said sleeve forming a peripheral flange around said sleeve, said sleeve having an inside diameter that tapers near the end plate to form a shoulder.
25. The stripper insert as recited in claim 24, wherein said end plate is formed having an aperture near center with respect to said sleeve, adapted to receive said punch.
26. The stripper insert as recited in claim 24, wherein said end plate having an aperture is formed by placing a stripper insert in alignment within said punch and die assembly and piercing said end plate with the punch and machining the edges of said end plate aperture by any combination of machining such as drilling, milling, filing, laser burning or by an electrical discharge machine to achieve the desired clearance between said punch and said stripper insert.
27. The stripper insert as recited in claim 24, including a recessed holding means to removably secure said stripper insert in a fixed manner within said stripper plate.
28. The stripper insert as recited in claim 27, wherein said holding means is a flat head socket screw.
29. The stripper insert as recited in claim 27, wherein said holding means is a ball or wedge lock located disposed on said stripper insert which extends into a recess within said stripper plate.
MIDDLETON & REUTLINGER
30. The stripper insert as recited in claim 27, wherein said holding means is a recess formed within said stripper insert to accommodate said ball or wedge lock extending from said stripper plate.
31. The stripper insert as recited in claim 24, wherein said peripheral flange is formed having at least one conical countersink contour to accommodate a recessed holding means in contact with said stripper plate.
32. The stripper insert as recited in claim 24, wherein said peripheral flange is formed having at least two conical countersink contours spaced in an irregular pattern to facilitate repositioning of said stripper insert during assembly and disassembly.
33. The stripper insert as recited in claim 24, wherein said peripheral flange is formed having a recess to facilitate repositioning of said stripper insert during assembly and disassembly.
34. The stripper insert as recited in claim 24, wherein said peripheral flange is formed having projections such as tabs to facilitate repositioning of said stripper insert during assembly and disassembly.
35. The stripper insert as recited in claim 24, wherein said end plate is of uniform thickness.
36. The stripper insert as recited in claim 24, wherein said end plate is thin enough in the center area to accommodate piercing. 37. The stripper insert as recited in claim 24, MIDDLETON & REUTLINGER
wherein said end plate is thicker in the center than the outer edge adjacent said sleeve.
38. The stripper insert as recited in claim 24, wherein said stripper insert is manufactured from metal.
39. The stripper insert as recited in claim 24, wherein said stripper insert is composed of a synthetic polymer.
40. The stripper insert as recited in claim 24, wherein said stripper insert is composed of a ceramic material.
41. The stripper insert as recited in claim 24, wherein said stripper insert is coated with a protective coating.
42. The protective coating recited in claim 41, wherein said protective coating is iron oxide.
43. The protective coating recited in claim 41, wherein said protective coating is black oxide.
44. The stripper insert as recited in claim 43, wherein said stripper insert is coated with a protective film.
45. A stripper insert for use with a punch press and stamping die assembly including: a punch, and upper die assembly, a stripper plate adapted to support stamping material disposed between the stripper plate and lower die plate comprising:
a generally circular disc of uniform thickness.
46. The stripper insert as recited in claim 45, wherein said disc is formed having an aperture near center adapted to receive said punch.
47. The stripper insert as recited in claim 46, wherein said disc having an aperture is formed by placing a stripper insert in MIDDLETON & REUTLINGER
alignment within said punch and die assembly and piercing said end plate with the punch and machining the edges of said end plate aperture by any combination of machining such as drilling, milling, filing, laser burning or by an electrical discharge machine to achieve the desired clearance between said punch and said stripper insert.
48. The stripper insert as recited in claim 45, including a recessed holding means to removably secure said disc in a fixed manner within said stripper plate.
49. The stripper insert as recited in claim 48, wherein said holding means is a flat head socket screw.
50. The stripper insert as recited in claim 45, wherein said disc is formed having at least one conical countersink contour to accommodate a recessed holding means in contact with said stripper plate.
51. The stripper insert as recited in claim 45, wherein said disc is formed having at least two conical countersink contours spaced in an irregular pattern to facilitate repositioning of said stripper insert during assembly and disassembly.
52. The stripper insert as recited in claim 45, wherein said disc is formed having a recess to facilitate repositioning of said stripper insert during assembly and disassembly.
53. The stripper insert as recited in claim 45, wherein said disc is formed having projections such as tabs to facilitate repositioning of said disc during assembly and disassembly.
54. The stripper insert as recited in claim 45, wherein said MIDDLETON & REUTLINGER
disc is thin enough in the center area to accommodate piercing.
55. The stripper insert as recited in claim 45, wherein said disc is thicker in the center than the outer edge.
56. The stripper insert as recited in claim 45, wherein said disc is manufactured from metal.
57. The stripper insert as recited in claim 45, wherein said disc is composed of a synthetic polymer.
58. The stripper insert as recited in claim 45, wherein said disc is composed of a ceramic material.
59. Method of sizing and securing said stripper insert, recited in claim 1 within said stripper plate to prevent movement of said stripper insert within said stripper plate during the pressing operation comprising the steps of:
a) selecting the correct size for the stripper insert based on the diameter of the punch;
b) providing a bore through said stripper plate having a diameter that is slightly less than the outside diameter of said sleeve of said stripper insert;
c) reaming said bore in said stripper plate to a size which will accommodate a light slip fit assembly with said sleeve of said stripper insert;
d) counterboring said reamed bore to a depth that will enable said stripper insert to fit flush within said stripper plate, and provide a slight clearance in diameter between said flange of said end plate of said stripper insert and said counterbore.
MIDDLETON & REUTLINGER
e) drilling and tapping threaded holes into said stripper plate in three places located in an irregular radial pattern around the periphery of said counterbore in order to secure said stripper insert to said stripper plate;
f) threadably connecting a clamp to one of the threaded holes of said stripper plate to temporarily hold said stripper insert in position within said stripper plate;
g) countersinking and machining a conical countersink contour into one of the two threaded holes of said stripper plate and said stripper insert to form a countersink threaded hole adapted to seat a flat head socket screw;
h) removably installing said flat head socket screw into said countersink threaded hole to hold said stripper insert into position and removing said clamp;
i) countersinking a conical countersink contour into the two remaining threaded holes of said stripper plate and said stripper insert to form two countersink threaded holes adapted to seat said flat head socket screws in said two remaining threaded holes; and j) removably securing said stripper insert within said stripper plate using said flat head socket screws for preventing any movement of said stripper insert within said stripper plate during the pressing operation.
60. Method of piercing an aperture in said end plate of said stripper insert, recited in claim 1, to receive a selected punch comprising the steps of:
MIDDLETON & REUTLINGER
a) setting an upper die assembly including said stripper plate containing said stripper insert into a press and slowly bring closing said press to move said upper die assembly together with a lower die section so that said stripper insert and said stripper plate make full contact with said lower die section;
b) lowering said punch to pierce said end plate of said stripper insert and to punch a scrap slug from said end plate, to form an aperture within said end plate having contours in the cross-sectional shape of said punch point; and c) machining said aperture such as by filing, drilling, or milling to providing clearance for said punch.
61. Method of sizing and securing said stripper insert, recited in claim 24, within said stripper plate to prevent movement of said stripper insert within said stripper plate during the pressing operation comprising the steps of:
a) selecting the correct size for the stripper insert based on the diameter of the punch;
b) providing a bore through said stripper plate having a diameter that is slightly less than the outside diameter of said sleeve of said stripper insert;
c) reaming said bore in said stripper plate to a size which will accommodate a light slip fit assembly with said sleeve of said stripper insert;
d) counterboring said reamed bore to a depth that will enable said stripper insert to fit flush within said stripper plate, and provide a slight clearance in diameter between said MIDDLETON & REUTLINGER
flange of said end plate of said stripper insert and said counterbore.
e) drilling and tapping threaded holes into said stripper plate in three places located in an irregular radial pattern around the periphery of said counterbore in order to secure said stripper insert to said stripper plate;
f) threadably connecting a clamp to one of the threaded holes of said stripper plate to temporarily hold said stripper insert in position within said stripper plate;
g) countersinking and machining a conical countersink contour into one of the two threaded holes of said stripper plate and said stripper insert to form a countersink threaded hole adapted to seat a flat head socket screw;
h) removably installing said flat head socket screw into said countersink threaded hole to hold said stripper insert into position and removing said clamp;
i) countersinking a conical countersink contour into the two remaining threaded holes of said stripper plate and said stripper insert to form two countersink threaded holes adapted to seat said flat head socket screws in said two remaining threaded holes; and j) removably securing said tripper insert within said stripper plate using said flat head socket screws for preventing any movement of said stripper insert within said stripper plate during the pressing operation.
MIDDLETON & REUTLINGER
62. Method of piercing an aperture in said end plate of said stripper insert, recited in claim 24, to receive a selected punch comprising the steps of:
a) setting an upper die assembly including said stripper plate containing said stripper insert into a press and slowly bring closing said press to move said upper die assembly together with a lower die section so that said stripper insert and said stripper plate make full contact with said lower die section;
b) lowering said punch to pierce said end plate of said stripper insert and to punch a scrap slug from said end plate, to form an aperture within said end plate having contours in the cross-sectional shape of said punch point; and c) machining said aperture such as by filing, drilling, or milling to providing clearance for said punch.
15. The stripper insert as recited in claim 1, wherein said stripper insert is manufactured from metal.
16. The stripper insert as recited in claim 1, wherein said stripper insert is composed of a synthetic polymer.
17. The stripper insert as recited in claim 1, wherein said stripper insert is composed of a ceramic material.
18. The stripper insert as recited in claim 1, wherein said stripper insert is coated with a protective coating.
19. The protective coating recited in claim 18, wherein said protective coating is iron oxide.
20. The protective coating recited in claim 18, wherein said protective coating is black oxide.
21. The stripper insert as recite in claim 1, wherein said stripper insert is coated with a protective film.
24. A stripper insert for use with a punch press and stamping die assembly, including a punch and an upper die assembly holding said punch, a stripper plate adapted to support stamping material disposed between said stripper plate, and a lower die plate comprising:
MIDDLETON & REUTLINGER
an upwardly extending cylindrical sleeve portion having an outside diameter of uniform dimension and a bottom end plate attached to said sleeve extending outward a distance greater than the radius of said sleeve forming a peripheral flange around said sleeve, said sleeve having an inside diameter that tapers near the end plate to form a shoulder.
25. The stripper insert as recited in claim 24, wherein said end plate is formed having an aperture near center with respect to said sleeve, adapted to receive said punch.
26. The stripper insert as recited in claim 24, wherein said end plate having an aperture is formed by placing a stripper insert in alignment within said punch and die assembly and piercing said end plate with the punch and machining the edges of said end plate aperture by any combination of machining such as drilling, milling, filing, laser burning or by an electrical discharge machine to achieve the desired clearance between said punch and said stripper insert.
27. The stripper insert as recited in claim 24, including a recessed holding means to removably secure said stripper insert in a fixed manner within said stripper plate.
28. The stripper insert as recited in claim 27, wherein said holding means is a flat head socket screw.
29. The stripper insert as recited in claim 27, wherein said holding means is a ball or wedge lock located disposed on said stripper insert which extends into a recess within said stripper plate.
MIDDLETON & REUTLINGER
30. The stripper insert as recited in claim 27, wherein said holding means is a recess formed within said stripper insert to accommodate said ball or wedge lock extending from said stripper plate.
31. The stripper insert as recited in claim 24, wherein said peripheral flange is formed having at least one conical countersink contour to accommodate a recessed holding means in contact with said stripper plate.
32. The stripper insert as recited in claim 24, wherein said peripheral flange is formed having at least two conical countersink contours spaced in an irregular pattern to facilitate repositioning of said stripper insert during assembly and disassembly.
33. The stripper insert as recited in claim 24, wherein said peripheral flange is formed having a recess to facilitate repositioning of said stripper insert during assembly and disassembly.
34. The stripper insert as recited in claim 24, wherein said peripheral flange is formed having projections such as tabs to facilitate repositioning of said stripper insert during assembly and disassembly.
35. The stripper insert as recited in claim 24, wherein said end plate is of uniform thickness.
36. The stripper insert as recited in claim 24, wherein said end plate is thin enough in the center area to accommodate piercing. 37. The stripper insert as recited in claim 24, MIDDLETON & REUTLINGER
wherein said end plate is thicker in the center than the outer edge adjacent said sleeve.
38. The stripper insert as recited in claim 24, wherein said stripper insert is manufactured from metal.
39. The stripper insert as recited in claim 24, wherein said stripper insert is composed of a synthetic polymer.
40. The stripper insert as recited in claim 24, wherein said stripper insert is composed of a ceramic material.
41. The stripper insert as recited in claim 24, wherein said stripper insert is coated with a protective coating.
42. The protective coating recited in claim 41, wherein said protective coating is iron oxide.
43. The protective coating recited in claim 41, wherein said protective coating is black oxide.
44. The stripper insert as recited in claim 43, wherein said stripper insert is coated with a protective film.
45. A stripper insert for use with a punch press and stamping die assembly including: a punch, and upper die assembly, a stripper plate adapted to support stamping material disposed between the stripper plate and lower die plate comprising:
a generally circular disc of uniform thickness.
46. The stripper insert as recited in claim 45, wherein said disc is formed having an aperture near center adapted to receive said punch.
47. The stripper insert as recited in claim 46, wherein said disc having an aperture is formed by placing a stripper insert in MIDDLETON & REUTLINGER
alignment within said punch and die assembly and piercing said end plate with the punch and machining the edges of said end plate aperture by any combination of machining such as drilling, milling, filing, laser burning or by an electrical discharge machine to achieve the desired clearance between said punch and said stripper insert.
48. The stripper insert as recited in claim 45, including a recessed holding means to removably secure said disc in a fixed manner within said stripper plate.
49. The stripper insert as recited in claim 48, wherein said holding means is a flat head socket screw.
50. The stripper insert as recited in claim 45, wherein said disc is formed having at least one conical countersink contour to accommodate a recessed holding means in contact with said stripper plate.
51. The stripper insert as recited in claim 45, wherein said disc is formed having at least two conical countersink contours spaced in an irregular pattern to facilitate repositioning of said stripper insert during assembly and disassembly.
52. The stripper insert as recited in claim 45, wherein said disc is formed having a recess to facilitate repositioning of said stripper insert during assembly and disassembly.
53. The stripper insert as recited in claim 45, wherein said disc is formed having projections such as tabs to facilitate repositioning of said disc during assembly and disassembly.
54. The stripper insert as recited in claim 45, wherein said MIDDLETON & REUTLINGER
disc is thin enough in the center area to accommodate piercing.
55. The stripper insert as recited in claim 45, wherein said disc is thicker in the center than the outer edge.
56. The stripper insert as recited in claim 45, wherein said disc is manufactured from metal.
57. The stripper insert as recited in claim 45, wherein said disc is composed of a synthetic polymer.
58. The stripper insert as recited in claim 45, wherein said disc is composed of a ceramic material.
59. Method of sizing and securing said stripper insert, recited in claim 1 within said stripper plate to prevent movement of said stripper insert within said stripper plate during the pressing operation comprising the steps of:
a) selecting the correct size for the stripper insert based on the diameter of the punch;
b) providing a bore through said stripper plate having a diameter that is slightly less than the outside diameter of said sleeve of said stripper insert;
c) reaming said bore in said stripper plate to a size which will accommodate a light slip fit assembly with said sleeve of said stripper insert;
d) counterboring said reamed bore to a depth that will enable said stripper insert to fit flush within said stripper plate, and provide a slight clearance in diameter between said flange of said end plate of said stripper insert and said counterbore.
MIDDLETON & REUTLINGER
e) drilling and tapping threaded holes into said stripper plate in three places located in an irregular radial pattern around the periphery of said counterbore in order to secure said stripper insert to said stripper plate;
f) threadably connecting a clamp to one of the threaded holes of said stripper plate to temporarily hold said stripper insert in position within said stripper plate;
g) countersinking and machining a conical countersink contour into one of the two threaded holes of said stripper plate and said stripper insert to form a countersink threaded hole adapted to seat a flat head socket screw;
h) removably installing said flat head socket screw into said countersink threaded hole to hold said stripper insert into position and removing said clamp;
i) countersinking a conical countersink contour into the two remaining threaded holes of said stripper plate and said stripper insert to form two countersink threaded holes adapted to seat said flat head socket screws in said two remaining threaded holes; and j) removably securing said stripper insert within said stripper plate using said flat head socket screws for preventing any movement of said stripper insert within said stripper plate during the pressing operation.
60. Method of piercing an aperture in said end plate of said stripper insert, recited in claim 1, to receive a selected punch comprising the steps of:
MIDDLETON & REUTLINGER
a) setting an upper die assembly including said stripper plate containing said stripper insert into a press and slowly bring closing said press to move said upper die assembly together with a lower die section so that said stripper insert and said stripper plate make full contact with said lower die section;
b) lowering said punch to pierce said end plate of said stripper insert and to punch a scrap slug from said end plate, to form an aperture within said end plate having contours in the cross-sectional shape of said punch point; and c) machining said aperture such as by filing, drilling, or milling to providing clearance for said punch.
61. Method of sizing and securing said stripper insert, recited in claim 24, within said stripper plate to prevent movement of said stripper insert within said stripper plate during the pressing operation comprising the steps of:
a) selecting the correct size for the stripper insert based on the diameter of the punch;
b) providing a bore through said stripper plate having a diameter that is slightly less than the outside diameter of said sleeve of said stripper insert;
c) reaming said bore in said stripper plate to a size which will accommodate a light slip fit assembly with said sleeve of said stripper insert;
d) counterboring said reamed bore to a depth that will enable said stripper insert to fit flush within said stripper plate, and provide a slight clearance in diameter between said MIDDLETON & REUTLINGER
flange of said end plate of said stripper insert and said counterbore.
e) drilling and tapping threaded holes into said stripper plate in three places located in an irregular radial pattern around the periphery of said counterbore in order to secure said stripper insert to said stripper plate;
f) threadably connecting a clamp to one of the threaded holes of said stripper plate to temporarily hold said stripper insert in position within said stripper plate;
g) countersinking and machining a conical countersink contour into one of the two threaded holes of said stripper plate and said stripper insert to form a countersink threaded hole adapted to seat a flat head socket screw;
h) removably installing said flat head socket screw into said countersink threaded hole to hold said stripper insert into position and removing said clamp;
i) countersinking a conical countersink contour into the two remaining threaded holes of said stripper plate and said stripper insert to form two countersink threaded holes adapted to seat said flat head socket screws in said two remaining threaded holes; and j) removably securing said tripper insert within said stripper plate using said flat head socket screws for preventing any movement of said stripper insert within said stripper plate during the pressing operation.
MIDDLETON & REUTLINGER
62. Method of piercing an aperture in said end plate of said stripper insert, recited in claim 24, to receive a selected punch comprising the steps of:
a) setting an upper die assembly including said stripper plate containing said stripper insert into a press and slowly bring closing said press to move said upper die assembly together with a lower die section so that said stripper insert and said stripper plate make full contact with said lower die section;
b) lowering said punch to pierce said end plate of said stripper insert and to punch a scrap slug from said end plate, to form an aperture within said end plate having contours in the cross-sectional shape of said punch point; and c) machining said aperture such as by filing, drilling, or milling to providing clearance for said punch.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US64412091A | 1991-01-18 | 1991-01-18 | |
| US644,120 | 1991-01-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2050540A1 true CA2050540A1 (en) | 1992-07-19 |
Family
ID=24583530
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2050540 Abandoned CA2050540A1 (en) | 1991-01-18 | 1991-09-03 | Stripper cup insert and method making |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2050540A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104227459A (en) * | 2014-08-22 | 2014-12-24 | 优德精密工业（昆山）股份有限公司 | Rapid machining jig for ball lock mechanism |
| CN108215246A (en) * | 2018-03-09 | 2018-06-29 | 湖南航天环宇通信科技股份有限公司 | The forming frock and its application method of porous multiple material product |
-
1991
- 1991-09-03 CA CA 2050540 patent/CA2050540A1/en not_active Abandoned
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104227459A (en) * | 2014-08-22 | 2014-12-24 | 优德精密工业（昆山）股份有限公司 | Rapid machining jig for ball lock mechanism |
| CN108215246A (en) * | 2018-03-09 | 2018-06-29 | 湖南航天环宇通信科技股份有限公司 | The forming frock and its application method of porous multiple material product |
| CN108215246B (en) * | 2018-03-09 | 2024-05-24 | 湖南航天环宇通信科技股份有限公司 | Forming tool for porous composite part and using method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3126776A (en) | Lawrence v whistler sr | |
| US3496818A (en) | Guide bushing for die sets | |
| CN101027156B (en) | Cutting tool and head with axial and radial stop surfaces | |
| US6402440B2 (en) | Tool assembly | |
| US4257292A (en) | Piercing units | |
| US5360300A (en) | Cutter shell | |
| AU6206400A (en) | Wedge-lockable removable punch and die bushing in retainer | |
| JP4775782B2 (en) | Drilling device | |
| US4403417A (en) | Draw punch | |
| US6033161A (en) | Revolving pilot tool | |
| CA2127064C (en) | Two part urethane punch stripper | |
| CA2050540A1 (en) | Stripper cup insert and method making | |
| US2928450A (en) | Self-contained perforating and countersinking unit | |
| US5471730A (en) | Method for refurbishing worn turret punch press bores | |
| US2377191A (en) | Drawing die | |
| US2920509A (en) | Drill bushing and jig | |
| US20060075871A1 (en) | Dual head punch with tapered neck | |
| US2927492A (en) | Knurled piercing punch | |
| US2942500A (en) | Slip head drill bushing | |
| US2212678A (en) | Perforating punch and die assembly | |
| CN210732852U (en) | Punching drill and laser welding tool thereof | |
| JP2884827B2 (en) | Cam type for press | |
| US2655995A (en) | Means for registering noncylindrical punches and dies | |
| US3763732A (en) | Punch press | |
| USRE22422E (en) | Perforating punch and die assembly |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |