US2214198A - Means for forming clinch nuts - Google Patents

Description

p 0- c. r. LANGMAID El AL 2,214,198

MEANS FOR FORMING CLINCH NUTS Filed June 13, 1939 s sheets-sheet 1 I Fig.1.

' INVENTORS Charles 7. Aqnymai Plum/" r 4". Qoub/e ATT p 10.1 0- c. T. LANGMAID Em 14,198

MEANS FOR FORMING CLINCH NUTS Filed June 15, 1939 3 Sheets-Sheet 2 Fig. Z).

- f3 1 as H a l 1NVENTOR5 Charles 7- Lanymo/d BY P/ummer ,6- D ble ORNEY5 p 1940- c. T. LANGMAID ET AL 2,214,198,

MEANS FOR FORMING CLINCH NUTS Filed June 13, 1939 3 Sheets-Sheet 3 WVENTORS C/yar/es TZLan m Plum/ner- Daub/ ATORNEY.

Patented Sept. 10, 1940 I V v UNITED STATES PATENT OFFICE MEANS roe FORMING OLINOH NUTS Charles T. Langmaid and Plummer E. Double,

. Detroit, Mich.

Application June 13, 1939, Serial No. 278,935 Claims. (Cl. 10-76) This invention relates to clinchnuts and has wardly. This results in a comparatively inparticular reference to the means for forming creased thickness of metal at the corners, which, clinch nuts, similar to the type disclosed in Petwhen again displaced outwardly over the securent No. 2,110,039 issued March 1, 1938. ing member during the attaching operation,

The nut proposed to be made through the makes a much firmer connection. 5 practice of the present invention, however, is The foregoing objects and advantages of the formed with the corners of the body portion invention, and, others, will be better understood rounded instead of square. as the description proceeds, reference being The practice of forming slight radii on the made to the accompanying drawings, which form 10 10 body portion has certain definite advantages in a part of the disclosure, wherein:

commercial practice. It has been found that Fig. 1 is a plan view of the forming and punchclinch nuts having bodies with absolutely square ing dies embodying our invention. corners oftentimes cause the metal of the secur- Fig. 2 is a vertical section taken substantially ing piece to crack at the corners when much on the line 2-2 of Fig. 1.

stress is placed on the nut so secured, whereas Fig. 3 is a view similar to Fig. 1, but showing the nut having the rounded corners will distribthe dies in the closed position or position of ute the stress and strain more evenly to the sework.-

curing piece. It has also been found that a nut Fig. 4 is an enlarged fragmentary detail in having the body formed with a. slight radius at section taken substantially on the line 4-4 of each corner is much easier located in the cor- Fig. 3, and illustrating the manner in which the 20 responding aperture of the securing piece. cams function to actuate the dies. The within invention contemplates the pro- Fig. 5 isa fragmentary detail, taken substanduction of such improved nuts by the means tially on the line 55 of Fig. 3 and illustrates herein disclosed whereby great economies in time the manner in which the nut is held in position and necessary equipment are effected. by the forming die during the piercing opera- 5 Nuts having the body portion formed with tion. rounded corners have heretofore been formed by Fig. 6 is an enlarged fragmentary detail taken cold heading methods, which are slow and substantially on the line 6-45 of Fig. 3, further comparatively expensive, in that they usually illustrating the piercing operation immediately require special cold heading machines and dies following the forming operation. This view fur- 30 with two or three or more stations, whereas this ther illustrates a portion of the tucker mechainvention calls for a device which forms the nism, showing. how the nut is maintained in the round corners and punches the hole in the nut slot under spring tension. I

at a single station, the forming die being uti- Fig. 7 is an enlarged fragmentary view, partly lized to hold the nut blank while it is being in section taken substantially on the line II 35 punched. of Fig. 3, illustrating the feeding mechanism for This improved device may be used on an orsupplying the nut blanks to the forming and dinary press and may be operated off the press piercing dies. header so that the forming and piercing may Fig. 8 is an enlarged fragmentary detail partly 4() be accomplished in a single timed operation. in section, illustrating a nut blank in position, 40

' With this device it is possible to form and pierce ready to be worked on in the forming operanuts at the rate of 200 strokes a minute, which tion. is double the present known production rate. Fig. 9 is a view similar to Fig. 8 but showing The invention has a further advantage, in that the nut blank after the body portion has been it permits a clinch nut to be formed with the formed with a radius at each corner and being 5 corners of the body rounded, without distorting held for the subsequent piercing operation. This the nut, and without the necessity of working view illustrates how the metal at the corners is on the flange of the nut as well as the body pordisplaced upwardly during the forming operation, as is done in the cold heading process. It tion.

is well known that the more the metal of the nut Fig. 10 is an enlarged fragmentary perspec- 50 is worked, the harder it becomes, therefore, the tive view of one element of the forming and harder it is to tap. holding die. This view illustrates the die cav- The means herein disclosed enables the manity with a vertical passageway for the entrance ufacturer to produce a clinch nut which has of the punch and the horizontal passageway for some of the metal at the corners displaced upthe entrance of the stripper pin. 55

Fig. 11 is a perspective view of a length'of preformed steel, from which the nut blanks arecut.

Fig. 12 is a perspective view of a nut blank before it is formed and pierced. This view illustrates how the body of the nut may be formed with a radius at each corner without in any wise distorting or affecting the flange portion of the nut.

Fig. 13 is the nut blank illustrated in Fig. 12 after it has been formed and pierced.

Fig. 14 is an enlarged fragmentary detail partly in section diagrammatically illustrating the tapping of the formed and pierced blank illustrated in Fig. 13.

Fig. 15 is a perspective view of the nut after it has been formed, pierced and tapped and ready to be secured to another element.

Fig. 16 is an enlarged fragmentary detail in section illustrating the manner in which the nut illustrated in Fig. 15 is secured to another element, such as a sheet of metal.

Fig. 1'7 is a perspective view of the wt illustrated in Fig. 15, after it has been at ached to an apertured sheet of metal.

Referring now more particularly to tl e drawings, it will be seen that the means for racticing our invention comprise the formirg and holding dies 20 and their associated elements, as hereinafter described. The disclosure shows a compound die capable of handling two nuts at a time. The forming and holding dies 20 are made in two sections 20a and 26b which are adapted to reciprocate in suitable slots 2|, formed in the bed plate 22, the latter being adapted to be secured in any suitable manner to a conventional punch press. The die sections 20!: and 20b are secured in the slots 2| by suitable plates 23, which plates are adapted to over-ride off sets formed along the sides of the die sections 20;; and 20b. The plates 23 are secured to the bed plate 22 by means of suitable machine screws 24. Angular heel plates 25 are secured to the bed late 22 by means of machine screws 26. The heel plates 25 are adapted to limit the return movement of the die sections 20a and 20b, and in addition thereto serve as supports and guides for the return bolts 21, which extend through apertures formed therein. The bolts 21 are threadedly secured as at 28 to the die sections 20a and 20b. Springs 29 are positioned between the heel plates 25 and the heads of the bolts 21, and are intended to hold the die sections 20a and 20b in the position of rest,shownin Figs. 1 and 2. The working faces of the die sections 20a and 201) are provided with two or more matched recesses 30, as illustrated in Fig. 10, wherein, it .will be seen that the recesses are formed with a slight radius 3| at each corner. Each recess 30 has a vertical passageway 32, extending into it, which passageway is intended to permit the entrance of the punch as hereinafter explained. Each of the die sections has a horizontal passageway 33, Fig. 10 communicating with at least one of the recesses 3|, which passageway 33 is intended to accommodate a stripper pin 34,

which is secured by any suitable means in the' bed plate 22. The stripper pins 34 are intended to strip the nuts from the recesses 30 as here-. inafter explained. Rectangular apertures 35 are formed in the bed plate 22 and communicate with chutes 36, Fig. 2, which are adapted to carry away the nuts after they have been formed and pierced as hereinafter explained.

It will be noted that there is but one stripper' pin for each die section. Gne pin for each section is all that is required for the reason that after the nuts have been formed and pierced as hereinafter explained, the nuts will be stripped from opposite sections of the dies by the edges of the feed slots 31, which are machined in the bed plate 22 and in which the nuts are held during the forming and piercing operations. The edges of the feed slots 31 adjacent the apertures 35 are machined away to enable the nuts to be pulled out of the feed slots 31 and carried over the apertures 35 by the movement of the respective adjacent die' sections. As the nuts reach positions above the apertures 35, they are stripped from the recesses by the pins 34 and dropped into the chutes 36.

Apertures 38' are formed in the bed plate 22 to accommodate the punches and to permit the slugs, which are punched from the nut blanks, tobe carried away.

Nut blanks are fed to the dies by means of tracks 39, which tracks communicate with conventional selection hoppers (not shown). A tucker track is secured to the bed plate 22 (Fig. 6) as at 4| and is adapted to communicate with the feed slots, 31 machined in the upper surface of the bed plate 22 and is adapted to carry nut blanks 42 from the feed tracks 39 .to the feed slots 31. A tucker 43 is adapted to ride in the tucker track 40 and move the nut blanks 42 into the feed slots 31. The tucker 43 is pro vided with a slot, in which is slidably mounted a pin support 44, to which is secured a pin 45, which is in turn adapted to engage a slot formed in the rocker arm 46, which is pivoted as at 41 to a suitable bracket secured to the bed plate 22. A compression spring 48 is positioned between the pin support 44 and the tucker 43 to givea resilient action. The rocker arm 46 is adapted to be actuated by the cam 49, which is secured by any suitable means to the punch press header 50. The return of the rocker arm 46 to its position of rest, as shown in Fig. l, is accomplished by means of the spring 5|. A set screw 52 is provided to serve as an adjustable stop for the rocker arm 46; The cam 49 is timed to actuate the rocker arm 46 and the tucker 43, so that a nut may be moved into position to be worked on before the die sections 20a and 20b become together.

The die sections 20a and 20b are actuated by the large cams 53, which are also secured by means of suitable machine screws 54 to the press header 50, as illustrated in Fig. 2. The press header 50 alsocarries the punches 55. The large cams 53 are bifurcated to permit the bolts 21 to operate there-through. The cams 53 are provided with" angular cam surfaces 56, which are adapted to engage correspondingly angular faces 51, which are formed on the die sections 20a and 20b. The bed plate 22 is provided with apertures 58 to permit the cams 53 to extend there-through. The cams 53 are timed so that they will actuate the die sections 20a and 26b I I after a nut has been placed in position in the feeder slot 31. The punches are timed to pierce the nut blanks'42 immediately after the forming operation and while the die sections the holes through the nuts are all accomplished in one downward movement, of the press header 50. This-enables us to accomplish several op- 20 the die sections 20a and 20!), causing them to am nes erations with one stroke of the press, thus obviating the necessity of having progressive dies with two or -more operating stations, thereby greatly increasing the production rate.

After the nuts are formed and pierced, they are then tapped as indicated in Fig. 14 and are ready for attachment to other elements, such as a sheet of metal 59 as suggested in Figs. 16 and 17.

The operation of the device is obvious from the foregoing description. The nut blanks are fed into the feed slots 31 by means of the tuckers 43. Their forward movement is arrested by the ends of the slots 37. Their backward movement is prevented by resilient pressure exerted on them by the tuckers 33. While the nuts are being held in the position just described, the continued downward movement of the press header 50 causes the large cams 53 to actuate approach one another. Upon the completion of the inward movement of the die sections, the bodies of the nuts held in this position are worked upon forming the radii at the corners.

After the forming operation and while the die sections are held in closed position and upon the same stroke of the press header 50, the punches 55 enter the openings 32 in the die sections, thereby piercing the holes in the blanks.

From the foregoing it will be seen that with this device it is possible to form the radii on the bodies of the nuts without in any way disturbing the corners of the flanges of the nuts as is the case in most cold heading processes.

Upon the upward movement of the press header 50 the die sections 20a and 201), under the influence of the springs 29, start their movement away from each other. The flanges of the nuts remain in the slots 3'! while the bodies of the nuts are firmly held in the recesses 30 of the die sections. The nuts are prevented from traveling in one direction with the die sections by the walls of the slots 31. The walls of the slots 31, adjacent the rectangular apertures 35, are machined away, however, so that the nuts may follow the die sections in the opposite direction and be removed from the slots 31. The nuts follow the receding die sections so holding them until they are immediately above the apertures 35, whereupon they are struck by the stripper pins 34. The nuts are then entirely free of the die sections and fall of their own weight through the apertures 35 into the chutes 36, from whence they are removed to the tapping machines.

Having described our invention what we claim and desire to secure by letters Patent is:

dies.

1. A device for forming round cornered, flanged clinch-nuts, comprising a base plate, blank feeding means, a groove in said baseplate adapted to engage the flanges of blanks received from said feeding means, dies for forming radii at the corners of the bodies of said blanks, means to actuate said dies and means to pierce said blanks While they are held in said forming dies.

2. A device for forming clinch-nuts from blanks having a T-shaped cross section, comprising a base plate adapted to be secured to a punch press, blank feeding means, a groove in said base plate adapted to engage one leg of the T-shaped blanks received from said feeding means, dies for forming radii at the corners of the other leg of said T-shaped blanks, cams carried by the punch press header for actuating said feeding means and said dies, and punches carried by said press header, adapted to pierce a hole in said blanks while the latter are held in said forming dies.

3. The combination with a punch press of a device for forming clinch-nuts, comprising a base plate adapted to be secured to said punch press, means on said base plate for receiving nut blanks, each comprising a body portion and a-flanged portion, dies carried by said base plate adapted to perform work on the body portions of said blanks, means carried by the header of said press for actuating said dies, a punch carried by said header for piercing holes in said blanks, while the latter are held in said dies, discharge means in said base plate, and stripping'means carried by said base plate adapted to remove the nut blanks from said dies and deposit them in said discharge means.

4. The combination as defined in claim 3, incl-uding means for feeding nut blanks to said base plate and means actuated by said press header for motivating said feeding means.

5. The combination with a punch press of means for making clinch-nuts, comprising a base plate, means on said base plate for receiving nut blanks, slidable dies carried by said base plate adapted to form radii on said nut blanks, heel plates secured to said base plate, resilient means supported by said heel plates for holding said dies in a position of rest, cam means carried by the press header for moving said dies into the position of work, punches adapted to pierce said nut blanks while said dies are in the working position, and means carried by said base plate for removing the nuts from said base plate and said CHARIES T. LANG-MAID. PLUMBER. E. DOUBLE.

Images