CA1068990A - Thermal isolation mounting for drawing and wall ironing ram - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A mounting for a long horizontally disposed reciprocal ram of a can forming machine. The ram which carries a punch or mandrel at one end and is connected to a reciprocating drive at its other end is supported intermediate its ends from the machine framework by a plate which slides in a guideway.
The plate, which extends parallel to the ram longitudinally thereof has a fixed connection at one end with the ram which is suspended beneath the plate. The plate which runs on guideways becomes very hot and is free to expand longitudinally independently of the ram since it has creep-accommodating connections through high thermal resistors with the ram at longitudinally spaced points which freely permit such expansion and resist transmission of heat into the ram.

Description

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In C~ll makillg ~quipmcnt ~hercill a rnan~lrc]. draws and irons ~ metal blank through suitablc drawing and iro~ing rings, it is mandatory to control thermal characteristics of ~.
the cooperatin~ parts to very close tolerances inasmuch as can ~` r bodies are now being made extremely thill and the metal must be uniformly distributed about the entire cylindrical body portion so that it is mandatory to maintain the parts initially in closest tolerance and in~alignment. ~lanclatory care is taken to preheat such machines to operating temperature and -~
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10 localized areas of wide ranging thermal gradients cannot he :~
tolerated. It has been found, for example, that by welding .; ~-;
the guideway support to the long ram, the support would ~.
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.. ~ become excessively heated and the thermal gradient which would deve].op between the support and the ram woultl cause the suT)port to wrap, thus destroying the structure. A typical type of apparatus to which the invention is applicable is shown in U. S. pate~t 3~735,629.
This invention is directed to a novel thermally stablc mounting for a ram of a can making machine.
20 A more specific object of the invention is to provide ~ .
t a mounting as above descri~ed which is allowed to expand freely from a single area of rigid connection to allow the heat-generating slldably supported rubbing portion of the ~.
; ram structure to expand and contract independently of the : ~
supported portion. -A further object is to provide a novel mounting in ~.
which the heat generating supporting structure is thermally isolated rom the supported structure and wherei.n the load carrying connecti.ons therebetween accommoclate independent thermal expansion and contraction of the structures rclati.ve to each other.

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'~ ' ~L0689~30 r These and other objects and advantage$ inllerent in and cncoJilpassed by ~ile invention will bccome more readily apparent from tlle specification and the drawings ~ erein:
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Figure 1 is a top plan view oL the novcl-tllermal mounti]lg asselll~ly;
~igure 2 is a side elevational view of the assembly;
Figure 3 is a cross-sectional view taken substan-; tially on line 3-3 of Figure 2;
Figure 4 is a cross-sectional view taken s-lbstan-tially Oll line 4-4 of Figure 2.
; The invention is shown in association with a can ma~-ing machine which has a ram 2 (only a portion of which is S}IOWJI) adapted for longitudinal reciprocation as well known in the art.
The distal end of the leading position 3 o the ram is provided witll a punch or mandrel which supports the can blank and moves thro~gh a series of dies (not shown).
The trailing end portion 4 of the ram is formed as a hollow air accumulator tube or container 5 which is suspended beneatll a slide plate 6.
The forward end portion 5a of the tube 5 is formed ~~ with a mounting block 7 having an upper planar mounting surface - 8 which affords a flat face seat at 9,9 for tlle bottom sides of wasllers 10 10 made of high thermal resistance material such as stainless steel~ The flat upper faces of these washers 10 seat against 2 flat bottom surface 12 of the slide pla~e 6 and serve to thermally isolate the adjacent leading end portion 13 the plate from ~he ralll 20 There are formed two opcnings 14 14 in tlle ~lock portion 7 of the ram which are in vcrtical alig~ cllt Wit]l openings 1~ iJI the respective washers and openings 16 16 for~ned in the leading end portion 13 of the slide plate. These openings 15 715 ~re spaced widthwise of the plate and are equally spaced from the opposite sides 17 1i of the block 7. A pair

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of close itting bolts 18 18 havc shanks 19 extcnding throllo}
res~ecti.vc aligncd opcnings 1~ 15 and tllC sh~nks llave ~lre.l(ls at their lower ends threaded into the thrcads 20 formed in - thn.openings 14. The upper ends of t]le shan]is arc formecl witll bolt heacls 21 which have s~louldcred cngagcment at 22 ~ :
Wit}l t]le ~'lat top slde 23 of the plate fi drawing the parts t.ightly together.
The.bolts 18 flank a securing pin 25 ccntered therebetween7 the pin 25 being tightly press-fitte~ into vertically aligned openings 26 27 formed respectivcly i.n the plate portion 13 and the forward end hlock 7 of the ram ~ ;:
body section 5. The assembly of the bolts 18 and the pi~
~~ 25 provides a si.ngle fixed anchor mcans for the plate to the ram in one localized area at the leading end of the plate .
portion 13.
The plate porti.on 13 is a skeletal element of one-piece construction having a pair of laterally spaced parallel .;- :
side iegs 29) 29 which are interconnected at their front ends by the portion 13 of the plate saicl portion 13 serving as a cross-member or bridge between the legs 29 29.
~_ The legs 29, 29 are interconnected in-termediate their encls approximately centrally thereof, by an integral : tie bar bridge or cross-member 30 and are interconnected . . by an integral tie bar, br1dge or cross-me.mber 32 adjacent to their trailing or l:ear ends 33 33.
The bridge members form with the legs a plurality ~-.
of vent openings 34 35, 36 and thermal c~ualizcrs 13 30 and ! ~, 32 between the legs serve to transmit heat therehetween.
The rea~ end portion o thc ram body section S
is formed with a U-shaped stirr~p-like mounting section 38 which comprises a lower cross wal.l 40 and upright side walls 41 41 which at their upper ends are ~ormed with horizontal

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coplanar faccs ~2 cach oE which seats ag.linst the bGttom ~:
flat sid~. o~' ~ high resistance tlow thcrmal conductive].y) ~.
washe-i~ 43'which may be made of stainless steel, for examl)le.
Each wasller 43 has a -flat upper face seated against the flat undersurfaee ]:2 oE the mounting or sup~ort plate 3.
l'he side walls 41, ~l are provided with threadecl , bo.~es 45, 45 i.nto which are threacled the lower threaded ends of sl~clnk portions 46, 46 of high thermal resistance bolts 47 made of stainless steel. The shank of each bolt 47 has -.
a shoulder 48 intermediate its ends having shouldered engagement ' with the top side of the associated washer 43.
The enlarged shank portions 49 of each bolt 47 extends through an oversize opening 5n in the plate 13 and at its upper ":~ , end has a head 51 which bears against the top side of a high thermal resistance washer 52 of stainless steel, the bottom -.
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side of the washer 52 seating against the f'lat top sul^face 23 o the plate 13. It will be a~parent that the sho-lldeTed engagement of the enlarged port;.ons ~9 of bolts 47 limits the,plate to only slight press,ure contact with the washèrs 52 to further mi.nimize thermal conductivity between the-plate ~_ 13 and the ram portion and also allows free expansion and contraction.
To maintain th,e plate 13 and ram section in longitudinal alignment a sine key 55 is secured to one of the walls 41 and projects above wall 41 into a guide slot 56 provided in the bottom of the plate 13 and elongated lengthwise of the ~lat.e thus uninhibiti.ng longitudinal expansion and contraction of the plate. The sides 57, 57 of the key ho~ever~ fit closely against the sides 58, 58 of the key way~,'thus inhibiting lateral di.s~lacement between the plate and ram. It will be noted that the plate is secured to the ram br only four thermal-creep accommodatir.g . 4 ,~
~olt conncc~:ions ~7 allcl is contlollc(l in j.ts i.on~i.t~lcl.al.
exllansion ancl contIaction by the sinc kcy asscm1-1y 55 5fi a~
that it only has a fixed dri.ving connection only at its front end i.n a limited area by the bolts 18 and pin 25. The p].ate and ram thus can expand and contract independently of eac.ll other bec.luse of the temperature graclicnts that clcvelop.
It will be noted that the ram portion 2 has a base WlliC]l provides an air accumulator chamber 6~. This chaml~er 60 has an inlet port 62 and an outlct port G~. ~ir is del.ive.red into the chamber and exllausts ly way of a valve (not shown) into the passageway 65 in a mandre~.-portion 3 of the ram, said mandrel portion 3 having at its forward ~- end (not shown) the can forming mandrel as well known to .
those sk.illed in the art. The passage of air through the chambered body portion of the ram also develops a temperature differential with respect to the mounting plate 13 which at its lateral edges 67, 67 is provided with wear strips ~
wllich ride along and upon opposing strips 69, secured to the top and bottom and vertical sides 7~, 71, 72 of the slide ways or slots 73, 73 provided in the frame structure of the apparatus.
In opera-tion, the ram and plate is reciprocated and the friction between the plate and supporti.ng frame generatcs a large quantity of heat which is transmitted to the plate.
The plate expands lengthwise primarily and since SUC]l is unrestricted it does not affect the expansion of the .;
tube portion o the ram.therebelleath. Very little, if any, heat is conducte(l from the plate. ~xcess heat in the plate dissapates through the ~ent openings and by conduction into the rame o-the machine.
It will be seen that -t]le front tong~le like portion 75 o the plate ~rojccts forwarclly o~ thc -fi.xcd ancllor " .

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area and l~roviclcs a. supJ or~ Çor an a;r va1vc (llOt ShOWIl) ~
.''~ no~;cl an~ E:fect:ive n~eans has hecn r)rovidecl to prevcn~ w~rr)ing o:E the conJIcctecl r)arts ancl ~hi.ch i.s dur.~ble and rel~tively ine~T)en!;ive.
This a7l::)pli.cation iS 2 division of application Serial No. 240,517, filed Novemher 26, 1975.

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Claims (4)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a metal forming apparatus of the type having a main frame mounting a longitudinally reciprocal ram, the follow-ing improvement:
a thermally controlled mounting for the ram comprising a plate, a slideway on the main frame receiving opposite edges of said plate, a localized fixed thermally conductive connection between one end of the plate and said ram, and means of high thermal resistance providing slidable connections between the plate and ram at locations spaced from said fixed connection lengthwise and widthwise of the plate.

2. The invention according to claim 1, wherein said plate is of skeletal construction and comprises a pair of laterally spaced continuous legs along the sides of the plate and a plurality of cross-members spaced lengthwise of the plate integral with the legs and defining air vent passages there-between.

3. The invention according to claim 2, and said ram comprising a heat dissipating hollow section in transverse alignment with said plate for accumulating and discharging air disposed in alignment with said vent passages, said plate over-lying said ram section and said vents accommodating passage of thermal currents therethrough.

4. The invention according to claim 3, and key and slot means interconnecting the ram and plate for guiding expansion and contraction thereof.