DE1065694B - Method and device for the production of blanks for bimetal rivets - Google Patents

Description

Various methods are known for the production of bimetal rivets for use as contact pieces. In an »advantageous production method, a bimetallic rod with a rectangular cross-section is used as the starting material The narrow side carries the required precious metal coating. The blanks are zylinr on these bimetal rods Drisch pressed and then by punching in the direction of its axis with the clad end first from Metal rod separated / t. The invention relates to the specified manufacturing process ...;, i

When the Zylindrisctipfressen * ¹ bljlinge of * * material occurs not only itiftdie recesses of 'pressing h' 'form, but he also gives way to the narrow sides

Method and device
for the production of blanks
for bimetal rivets * J.

"','"<; - ■ '■ ■ · · ■' Applicant: .. ". ■ ■ '■.' ■ Y:
Fr. Kammerer JAk ^ engesellschaft,
/ :; - ■ .; - ; 'Pforzheim; * - ■, '■. ",'

Emil Kunzmaan, Etsihgen about Pforzheim, has been named as the inventor

of the staff. This creates the

Notches on the two end pins of the blanks, tips, i During the subsequent punching out of the blanks he ' .

consequently give themselves to theirs. Front face ^: ~~ "!" ~ ] '~~

jumped when the blanks, as esf with the known. , ■ _: '' 2 ^v ''

'Procedure is the case, immediately and only through, ao *,>, · . ^l! "i '''■■' i * '* -' * ■ '~' ■ '* ..' ■

sharp notches ■ are separated from each other. It accommodates at least ^ a tenes of the / precious metal

it can easily happen here that these projections are firmly attached to the ;, metal rod, finer- one, *. at-

ter so in the contact surfaces of the rivet / pressed-ordered molding jaw; with recesses for

that rejects arise. By removing several blanks sojvie ^ a changing upper, sorting 'the same, additional costs are incurred -' »5 surface det _} Base plate -, btewegbsire, similarly designed.

causes. _> "'' ■ · 'saved the pressure jaw and" your next holding jaw,

According to the invention, when cylindrical pressing

at least part of the 'plating in the form of a narrow marginal strip from the deformation nomnien and also between neighboring raw linger a - w ^ hn-iuch small - ^ distance aware ^ and the metal rod in this area with the exception of the -non-deformed 'marginal strip too thin,' aie , Connecting blanks, 'S.tegen. compressed. 'This is followed, as in known procedures, the punching the blanks. This is expediently done; testify to the cylindrical cross-sectional shape of the raw material _:

would not work step by step, but - as in itself - <tickahnt - in a single pressing process, whereby ■

the material displacement towards the narrow sides of the 40 punched blank,

^ abes is particularly low., A tipping t Fig. 4 the same rivet blank as Fig. 3 occurs by 90 ° ^f i to a small extent. "thus only high on the rotated,

unplated side of the rod on and here too no longer or only to an insignificant extent,

the blanks themselves, but practically wischepstegen only on ■ the coming into discontinuance during the subsequent punching * "* l. Ba is the weight of the die is conceivably low, only fall proportionally

low cutting costs for the precious metal it contains. You can buy a rectangular one on one narrow side with half-sleeves. i '/ t , ■ '■ * ■■■ ^c metal 14 clad steel> it from the original sides lu-r

An advantageous procedure for performing the cylindrical pressing / the cylindrical pressing takes place

but not progressively in several consecutive and decreasing recesses : tMWl'1'4

whose 'last recess, together with the last recess of the mold jaw one with the bore of the Schntttmatrize has a common axis. , ■■ "The method and a device according to the invention is based on yohj drawings showing an leadership example; one? device according to the invention, and blanks produced according to "the invention as £ places, described. It shows ,

. Ong. 1 shows a top view of a bimetallic material preformed according to the invention; *

FIG. 2 4en, the same rod as FIG. 1 in side view, FIG. 3 shows a bimetallic rod according to the method according to the invention; according to FIGS. 1 and 2

* Tiig. 5 a device according to the invention twm

Manufacture of, bimetal rivet blanks in Gruiulriü, 6 shows a section along line VI-VI in FIG. 7 shows a section along line VII-VII of FIG. C, Fig. 8 is a section along line VIII-VIII of

Fig. 6i

According to FIGS. 1 and 2, the starting material is in the form

took

An advantageous way of carrying out the method according to the invention has a base plate containing the cutting die with a groove for

'4 t

BATH ORIGINAL

Claims (3)

two cylinders get a thin, narrow web 11 io going punching mandrel 31 now first separates the cylinder remains. In addition, the cylindrical deformation Rischen blank is carried out from the thin webs 11 and not across the entire width of the rod, then punches it through the narrow precious but there remains a narrow edge strip 13 on the metal edge 13 and the underneath in, the base plate! the side of the Edehnetallauflage 14 undeformed. The built-in cutting die 32 through. The tips 12 in this case then arise only on the base of the separated small waste through an OfF-metal side and also there no longer on the rivet blank opening 33 on the underside of the stop 30 itself, but on the intermediate webs 11. In the following tool the end. The process starting from the die 32 is the cylindrically pressed stepping rivet blank is then separated in a known part from the rest of the rod by using the method in the bore of a turntable or a non-deformed noble metal side on a cut or other suitable device Pressing tool die containing base plate is placed and fed in for the rivet head. Width direction, d. H. Direction of arrow C, of the bimetal · For the execution of the invention shift also other rod is punched out (Fig. 3). Tool shapes are possible on the resulting tool. It is essential, however, that the rivet blank does not have a tip or burr formation on the blank through thin, narrow webs and on the side of the rivet head, while the narrow edges 13 on the precious metal side remain connected to the bimetal rod connected to the tip at the opposite end and remain on remain on the web ejected as waste. is preferably preformed in a pressing operation. According to the punching direction selected, it is impossible to pull base metal onto the noble metal at the cut surfaces. At most one tip 15 of the noble metal can be pulled over onto the surface of the base metal (FIG. 4). An apparatus for carrying out the method according to the invention is shown in FIGS. 5 to 8, for example. According to the exemplary embodiment, a fixed form and guide jaw 17 is inserted into a base plate 16. Opposite this there is a movable mold jaw 18 with a downstream holding jaw 19, which is supported by a cover plate; 20 are held from above and are moved in the direction of arrow D through the press. The jaw 17 on the one hand and the jaws 18 and 19 on the other hand have exactly opposite, semicircular recesses 21 and 22 and 23 Holding jaw 19 only serve to hold the deformed rod in place during punching. The bimetallic rod 24, with the noble metal side resting on the base plate 16, is introduced into the tool under a pressure ram 25, the pressure ram 25 by means of a compression spring 26 to place the bimetallic rod 24 on the base plate 16 for permanent contact with the ^ in FIGS. 1 and 2 visible narrow edge 13 on. To obtain the precious metal side, the base plate 16 is given a correspondingly deep groove 27 that goes through in the direction VI-VI, so that the bimetallic rod is below the lower edges of the jaws 17, 18 and 19 by its depth. The bimetallic rod 24 is first inserted into the first liner between the mold jaw 17 and the press jaw 18, and the first round product becomes the following: 1. Process for the production of blanks for bimetal rivets from one on a narrow side Clad bimetal rod on which the blanks are first pressed cylindrically and then by punching separated from the metal rod in the direction of its axis with the clad end first are, characterized in that at least part of the cladding during cylindrical pressing (14) in the form of a narrow edge strip (13) excluded from the deformation and between adjacent blanks a distance is maintained, in the area of which the metal rod each to one thin, the blanks connecting web (11) is pressed together. 2. The method according to claim 1, characterized in that the round cross-section of the blanks is produced in a single pressing process. 3. Device for performing the method according to claim 1 or 2, characterized Through a base plate (16) containing the cutting die (32) with a groove (27) for receiving at least a part of the noble metal layer of the metal rod, also one fixed to it ... arranged molding jaw (17) with recesses ■: for receiving several blanks (21) as well as one lx'wejibare on the surface of the base plate (16). similarly recessed press jaw (18) are you downstream holding jaw (19). their last recess together with the last recess the molding jaw has an axis common to the bore of the cutting die. Publications taken into consideration: Swiss Patent Specifications Xr. 170 577. 818. 1 sheet of drawings BATH ORIGINAL