US1972179A

US1972179A - Apparatus for expanding metal laths

Info

Publication number: US1972179A
Application number: US619186A
Authority: US
Inventors: Herbert K Baker
Original assignee: PENN METAL Co
Current assignee: PENN METAL Co
Priority date: 1929-04-24
Filing date: 1932-06-25
Publication date: 1934-09-04
Anticipated expiration: 1951-09-04

Description

Sept. 4, 1934. H. K. BAKER 1,972,179

' APPARATUS FOR EXPANDING METAL LATHS I ori inal Filed April 24, 1929 10 Sheets-Sheet 1 O ooooooooooooo Y I A oRNEYs Sept. 4, 1934.

Oyiginai Filed April 24, 1929 10 Sheets-Sheet 2 INVENTOR A.

H. K. BAKER Sept. 4, 1934.

APPARATUS FOR EXPANDING METAL 'LATHS Original Filed April 24, 1929 10 Sheets-Sheet 3 j 5 3 ATTONEYS Sept.- ,4, 1934. H. K. BAKER APPARATUS FOR EXPANDING METAL LATHS Original Filed April 24,

1929 10 Sheets-Sheet 4 lIl INV %OR 7 i M62 BY My! ATTRNEY-S 3 III lllllll H. III w J m Arm X Tww ata no onu a".

Sept. 4, 1934. n H. K. BAKER 1,972,179

APPARATUS FOR EXPANDING METAL LATHS Original Filed April 24", 1929 lo'sheets-sheet 5 INVENTOR Maw/ M A Sept. 4,1934; H. KJBAKER 1,972,179

I APPARATUSFFOR EXPANDING META'L' LATHS ofi ina Filed April 24. 1929 A 10 Sheet-Sheet e p 34- H. K. BAKER 1,972,179

APPARATUS FOR EXPANDING METAL LATHS Origins i1 Filed April 24', 1929 10 Sheets-Sheet 7 ENTQR Sept. .4, 1934.

' APPARATUS FOR EXPANDING METAL LAElHS' Originai Filed April 24, 1929 10 Sheets-sheaf. 8

INVENTOR H. K. BAKER I 11,972,179 j I i I l I v v I -'r 1 I l I Sept. 4, 1934. H. K. BAKER I APPARATUS FOR EXPANDING METAL LATHS Original Filed April 24, 1929 10 Sheets-Sheet 9 AT RNEYS Patented Sept. 4, 1934 1,912,179 APPARATUS FoaExrANnrN METAL LA'rns Herbert n- Baker, Detroit, Mich, assignor to Penn Metai Company, Parkersburg, W. Va., corporation of Massachusetts Original application April 24, 1929, Serial N 1 357,643. Divided and this application June 25, 1932, Serial No. 619,186 I 12 Claims. (01. Mai-6.6)

the least possible strains, to the mesh work,

which. tend to result in a weak and easily broken finished product.

,More specifically, I contemplate the employment of a pre-opening operation in order to fac'ili'tate the subsequent and complete expansion oithe; mesh work.

It is also an object of the invention to reduce the angle or" divergence of the expander guides in order that the blanks may not be subjected to any sudden tearing strains during expansion and in order to simplify the driving mechanism for the rollers which feed the blanks through the diverging expander guides.

I also contemplate making the cooperating elementsof the guides in such a manner and of such materials as to give them very great operating life and render them inexpensively and readily renewable.

How the foregoing objects and advantages are obtained together with others which are incident thereto, will be clear from a consideration of the following description taken with the accompanying drawings which illustrate the preferred embodiment of the invention and in which Figs. 1a and 1b constitute a top plan View of the pro-opening and expanding apparatus of the present invention;

Figs. 2a and 2b taken together form a side elevational view of the apparatus shown in Figs. 1a. and 1b;

Fig. 3 is an enlarged sectional view taken thru certain parts of the pre-opening mechanism substantially as indicated by the line 3-3 of Fig. 2a; 7

Fig. 4 is an enlarged longitudinal section thru the pre-opening mechanism taken as indicated by the line l-A of Fig. 1a; i I Figs. 5 to 8 inclusive are somewhat diagrammatic views (taken as described hereinafter) oi details of the pre-opening mechanism including sectional showings of certain of the guides with a blank therebetween;

Figs. 9 and 10 are sectional views of the expander guides taken as indicated by the'lines 9'9 and 10-l0 of Figs. 1a and lb respectively;

Fig. 11 is a sectional view thru the delivery end of the apparatus of the present invention taken substantially as indicated by the line 1111 of Fig. 11);

Figs. 12 and 13 are face and sectional views, respectively, of a slitted and ribbed blank adapted to be expanded by the apparatus and according to the method of the present invention; and

Figs. 14 and 15 are face and sectional views, respectively, of a portion of a completely expanded sheet of lath.

Before describing in detail the apparatus and its method of operationherein disclosed, it should be understood that the invention is particularly concemed with the completion of what is now well known in the art as high rib lath the same having relatively high ribs or grooves formed in the unslitted strips extending longitudinally of the sheets between mesh work sections, in contradistinction to what is commonly called flat rib lath whichis usually provided with very shallow beads extending longitudinally thru the unslitted strips of a sheet. It might also be observed that the relatively deep grooves of the former type of lath are provided primarily for the purpose of giving the sheet strength and rigidity while the very shallow beads of the latter type are commonly employed in order to provide means whereby the blanks may be guided thru an expanding mechanism. a

In order that the method and apparatus of the present invention may be more 'readilyunderstood, reference should first be made to Figs. 12 to 15 inclusive, Nos. 12 and 13 of which illustrate the condition of the blank just prior to the time of entering the mechanism of the present invention and Nos. 14 and 15 of which illustrate the lath after it has been delivered from the mechanism of the present invention in a completely expanded form. A method and apparatusfor producing blanks of the type illustrated in Figs. 12 and 13 is disclosed in my copending application Serial No. 356,331, filed April 19, 1 929. I

It willbe observed from the'figuresjust above noted that the blanks are providedwith pairs of longitudinally extending slitted areas, the slits being arranged to provide strandsS which are arranged in staggered formation and are inclined longitudinallyjof the blank. I The strands S in each area, it will be observed,are inclined reversely to those of the other slitted'area of the pair. Between the pairs 'of slitted areas are unslitted strips X which are relatively wide and thru which extend the relatively shallow beads B. The beads B are adapted to be engaged and folded up into the relatively high ribs indicated at B in Figs. 14 and 15 by means ofthe apparatus to be described hereinafter.

It is also to be noted at this point that angled grooves G extend longitudinally of the blank between the slitted areas of each pair, the legs of the grooves G preferably extending substantially at right angles to each other and overlying or taking in a portion of the-slitted areas on either side. Note also that the beads B and the grooves G are arranged in alternate formation transversely of the sheet and that all of the grooves G project to one side or face of the sheet while the beads 13. project toward the other.

From inspection of the drawings, particularly Figs. 1a, 1b, 2a, 2b, 3and 4, it will be seen that the apparatus of the present invention is mounted on a bed plate or table 16 which is suitably supported on uprights or standards 17.

The apparatus for accomplishing the pre-open ing of the lath (see Figs. 1a, 2a, 3 and 4) includes the upper and lower cooperating sets of feeding rollers 18 .and 19 respectively which are adapted to engage the relatively shallow beads B to start the blanks thru the apparatus and which are suitably mounted onshafts 20 and 21', the latter being journalled in supporting members 22 secured to and-extending upwardly from the bed plate 16. Note that the lower shaft 21 is journaled directly in the members22 and that the upper shaft 20 isjournaled therein indirectly, so to speak, by means of bearing blocks 23 mounted for vertical movement between jaws opening from the top edges of the members 22. Bracket members 24 bridge the jaws and are providedwith adjusting bolts 25 for securing the blocks 23 in'position to bring the working surfaces of the upper and lower cooperating

rollers

18 and 19 into position for gripping and feeding the blanks as they are fed into the apparatus. The manner in which the blanks are gripped and fed by the

rollers

18 and 19, just described, as well as by those to be describedhereinafter, is clearly illustrated inFigs. 5 to 8 inclusive.

Extending forwardly from the working surfaces of the

rollers

18 and 19, I have provided cooperating pairs of upper and lower guides-for engaging the beads'B and guiding the blanks forwardly until they: are engaged by other rollers which perform the folding up operation. These guides are indicatedby the reference characters26 and 2'7 in Figs. 1a,-;3;-4 and 6 and it should be'noted that these guides extend forwardly in. substantially parallelrelation to the bed plate 16, the same being' supported on thebed plate by means of the upper and

lower brackets

28 and 29 see Fig. 4)

Before the blanks pass outof the guides 26 and27- their angled grooves G areengagedby the

upper andlower rollers

30 and 31 which have similarly angled working surfaces. However, these rollers 39 and'Bl-are arranged to extendthe legs of the grooves G; and'thus take in an additional strip of the slitted. areas on either 'side thereof, The

rollers

30 and 31= are mounted on the shafts 32 .and 33'the samebeingjournaled'in the uprights 22 similarly to theshafts 20 and-21; including a direct bearingrfor the shaft 33 and the bearingblocks34 for theshaft 32 mounted between. jaws which are closed'or bridged by the members '35 and bolts 36 for tightening the rollers intheir gripping-position.- v

Extending forwardly fromthe working surfaces ofjthe

rollers

30 and 31, I have arranged the cooperating guides 37 and 38 having gripping surfaces which gradually change or taper from their entrance ends to their delivery ends in such a manner as to gradually release or uncover the portions of the slitted areas which are included in the legs of the angled grooves G of the blanks which they engage. That is, they taper from a configuration substantially the same as that of the grooves as delivered from the

rollers

30 and 31 to a configuration substantially as indicated in Fig. 8. Figs. 7 and 8 clearly indicate this change, but it should be observed that these figures are not taken at the extreme ends of the guides, but are taken in section at points intermediate their ends, i. e. substantially at the mid-points of the two sets of upper andv lower folding rollers now to be described.

' As hereinbefore noted the first set of upper and

lower rollers

39 and 40 are positioned at the delivery ends of the

guides

26 and 27 and it should be observed that the working surfaces of these rollers are configured to-grip substantially the entire unslitted-areas X of the blanks and fold them up into grooves whose legs extend at Snstantially right angles to each other. Stated in another way the rollers 39*and 40 deepen and enlarge the relatively shallow beads B; by taking in the unslitted areas on each side thereof. The

rollers

39 and 40 are mounted on shafts 41 and 42, thesame being journaled in the members 22 in exactly the samemanner as the

shafts

32 and 33 hereinbefcre described. 1

The second set of

rib forming rollers

43 and 44 are positioned and mounted on

shafts

45 and 46, the said shafts also being mounted in the manner hereinbefore described. These rollersgas will be seen from inspection of Fig. 8, have working surfaces which fold up theright angled ribs into substantiallyU-shaped'configuration. Short cooperating guides 47 and 48 (see Figs. 1a and 4) serve to direct the ribs of the blanks as they pass thru the apparatus from the

rib forming rollers

39 and 46 to those numbered 43 and 44-. Supporting brackets 49 and 50 are positioned between the sets of

rollers

39,40 and 43, 44, the same serving to support the guides 47 and 48 as well as those numbered 37 and 38.

The shafts for each of the lower sets of roller i. e. those numbered 21, 33, 42 and 46, are driven from the main drive shaft 51 thru the intermediatesprooket and-chain connection, 52, 53 and 54,.with; the shaft 46, the other shafts being connected therewith by means of the

gears

55 and 56 mounted on the shafts themselves and the

idlers

58 and 59 intermeshing therewith. From inspection of Fig. 25;, it will be seen that this gearing arrangement provides a synchronized drive for all of the upper and lower roller shafts.

The apparatus for accomplishing the expanding is also mounted on the'table 16 and in general consists of a number. of pairsof diverging guides and rollers for feeding the blanks therethrough; The receiving ends of the first sets of upper andlower guides 60 and'61 are positioned adjacent to the working surfaces of the rollers 43 1,;

other in a horizontal plane and are supported by i and 63 re- All it should be observed that the guides and it should means of the

members

64, 65, the latter being carried by the uprights 69 secured tothe table 16 at each side thereof (see Figs. la and 2a). Cooperating pairs of upper and lower gripping and feeding rollers are arranged at the delivery ends of the pairs of

guides

60, 61, the same being indicated: by thereierenoe characters 66 and 6'7. A shaft 68 upper rollers 66, the said shaft being journaled at its ends in the standards 69 by means of bearing blocks 70 mounted for vertical movement in the jaws which are formed at the top of the members 69 and which are indicated in Fig. 2a at '71. The upwardly opening jaws '71 are closed by the bridge members 72 and adjusting bolts 73 are provided therein. This journal construction is similar to that described in connection with the

shafts

20, 32, 41 and 45 with the exception that the adjusting bolts 73 react thru the intermediation of springs 74 instead of directly against the blocks 70. The lower rollers of the cooperating pairs now under consideration are mounted on the shaft 75 which is journaled directly in the members 69. a

Extending forwardly from the delivery side of these rollers are other pairs of diverging

guides

60, 61 which are similar in all respects to those already described. At their receiving ends they are spaced and supported in a suitable manner by means of the transverse bracket members 76 and '77 while at their other ends they are engaged and supported by

members

64 and 65 constructed and supported in the same manner as those previously referred to, provision being made, however, for engagement of the

guides

60, 61 at intervals which are farther apart than those at the delivery ends of the first described pairs of

guides

60, 61. Feeding rollers and supports are provided at the delivery ends of the second mentioned set of be noted that this construction including the uprights 69, shafts 68 and and supporting

members

64, 65 and '76, '77, is identical with'that already described with the exception that the rollers 66 and 67 are more widely spaced and that the guides are arranged to de liver and receive the blanks at the spaced intervals occurring between, the rollers.

A third construction of this character is positioned and supported on the table 16' beyond those already referred to and it should be noted that these constructions are spaced longitudinally of the table at substantially equal intervals.

At this point it might be observed that the cross sectional configuration of the

guides

60, 61

" and the rollers 66, 67 are adapted to engage and maintain the formation of the ribs of the blanks during the expanding operation. Note also'that the

guides

60, 61 are of special construction in order to reduce wear and facilitate replacements.

ccording to this construction the main bodies of the-guides 60, 61 are formed of cast metal, the lower guides 61 having grooves adapted to embrace or engage the ribs and the upper guides 60 being provided with renewable strips or knives '78 (see Figs. S te 11 inclusive). Theseknives I8 are received in suitable longitudinally extending slots in the guides 60 and are secured in position by means of the pins 79, the same preferably being of wedge- -like formation in order to ensure tight gripping contact in the'openings provided therefor the

guide members

60 and 78. The knives '78 extend into and thus maintain the formation of the ribs during the expanding operation and knives 78 are preferably made of steel. I

serves to support and drive all of the,

directly mounted in The metals here employed, i. e. cast iron and steel, make for the strongest and longest lived guide construction possible. The knives employed must be relatively th n and, therefore, would not be of suflicient strength if made of cast iron, be-

cause such metal, as is well known in the art, is relatively brittle. I have constructed these knives, therefore, of steel in order that they may have greater strength, and have constructed the bodies of 'theguides 66 oicast iron in order to reduce the cost of production of the parts. The lower guides 6l may be constructed entirely of cast iron in View of the fact that no relatively thin knives or parts are necessary in a guide of grooved formation. Furthermore, the cast. iron employed in making the lower members wears very slowly. This construction, therefore, results in inexpensive manufacture as well as longer life of the guide members than was possible heretofore.

Mounted on the table 16 at the delivery ends of the last pairs of diverging

guides

60, 61, are supporting members or uprights (see Figs. 1b, 2b and 11) and supported in these members 80 I have provided a fourth set of upper and lower feeding'rollers 66 and 67 mounted on upper and lower shafts 68 and '75 in the same manner as hereinbefore described. The lower shaft 75 in this case is directly journaled in the members 80 while the upper shaft 68 is provided with bearing blocks '70 which are mounted for vertical movement between the jaws 81, the latter being bridged inthis instance by means of the members 82. Adjusting bolts 73 and springs '74 are also provided in this instance.

The delivery ends of the

guides

60, 61 of the last set are supported'by means of the transversely extending supporting

members

83 and 84 in position to deliver the ribs of the blanks to the cooperating tongue and groove working surfaces of the rollers 66 and 67. This last or delivering set of rollers feeds the blanks to the straightening guides and rollers located immediately therebeyond. The straightening guides are constructed similarly to those already described and from ins so .on of Figs. 1b and 11, it will be seen that they are again mounted or supported by transversely extending

members

85 and 86. 1

Beyond the

guides

87 and 88 in the direction of feed to the apparatus are arranged two upper and three lower straightening roller shafts 89 1' the three lower ones 90 being the uprights 86 and the two upper: ones 891being arranged in staggered relation to the lower ones and being carried by the journal boxes 91 between jaws 92, the latter being closed by means of the binder or bridging member 82. The mechanisms indicated by the reference character 93 serve to adjust the vertical position and 99 respectively,

. of theblocks 91.

The upper'shafts 89 are provided with straightening rollers 94 having circumferential tongues on their working edges for engaging the interior of the ribs ofthe expanded sheetswhile the lower shafts90 are provided with rollers 95 having circumferential grooves at their workingedges for engaging the outside of the ribs. Each pair of shafts 68 and '76 for the feeding rollers 66, 67: are interconnected by means of gears 96 and 97 (seeFigs. 1a, 1b, and 3) and all of the lower shafts drive shaft 51 by means of the chain connections indicated in Figs. 1a., 1b, 2a and 212 by the referencenumerals 96, 99,106 and 101, each succeeding connection being provided with suitable sprockets 102 keyed to the shafts '75 and 51-.

"(5 are connected to the main 3 .which feed r the

rollers

30 and 31.

The driving mechanism for the delivering or straightening rollers includes a chain connection 103- between the last of the lower shafts and the first of the straightening roller shafts 90, each of said shafts being provided with a cooperating sprocket wheel 162 (see Figs. 1b and 2b). All of the lower shafts 90 have gears 104 which are interconnected bymeans of the idler gears 105 all positioned at the side of the apparatus adja cent to the chain driving mechanism. At the other side of the apparatus the upper roller shafts 89 are provided with gears 106 which mesh with a gear 107 keyed to the central lower shaft 90 at the same side of the apparatus. It will be seen, therefore, that the forming

rollers

18, 19, 30, 31, 39, 40, 43, 44 and'the feeding rollers 66, 67, as well as the straightening

rollers

94 and 95 are all driven in timed relation from a single driving shaft, i. e. the shaft 51 which, as shown in Fig. 1a is provided with sprocket wheels 108 for coupling with any suitable source of power.

In considering the operation of the apparatus and also the advantages incident thereto, reference should first be made to the drawings illustrating the pre-opening parts of the mechanism, particularly Figs. 5 to 8 inclusive. When a blank of the character hereinbefore described '(see Figs. 12 and 13) is fed into the front end of the machine, its relatively shallow beads B are first engaged by the initial pairs of feeding

rollers

18 and 19, the said rollers having working faces of circumferential bead and groove configuration the beads B of the blank and thus serve as guides therefor (see Fig. 5). As the blank is fed forwardly by the

rollers

18 and 19, the beads B as well as the unslitted areas on each side thereof are engaged by the cooperating guides 26 and 27. About midway of the

guides

26 and 27, the angled grooves G in the center of the slitted areas are engaged by the rollers 30 and '31 which, as already observed, extend the legs of the grooves G and take in an additional portion of the slitted areas. It should be observed that this is accomplished (see Fig. 6) by'extending the legs downwardly while maintaining the centers or tops of the grooves substantially within thegeneral plane of the sheet. As shown in Fig. 6 the tops of the angled grooves G are held (by means of the rollers 30 and 31) in the "same plane in which the

guides

26 and 27 hold the unslitted areas X with their beads B. This operation slightly inclines the portions of the slitted areas which are not taken in by the

rollers

30 and 31, the inclination, as will be seen from inspection of Fig. 6, being downwardly from the

guides

26 and 27 toward the lower extremity of the legs of the angled grooves G andit might also be noted that this operation very-slightly stretches or opens the strands which are not taken in by Upon passing thru the

rollers

30 and 31 the blank moves forwardly thru the

guides

37 and 38 which, as already pointed out, are of a cross-sectional configuration similar to th'at of the

rollers

30 and 31. These guides, as will be seen from inspection of Fig. 4, guide the angled grooves of the'blank forwardly until the blank is delivered to the

guides

60 and 61 of the expander proper. Two sets of ribs engaging and forming

rollers

39, 40 and 43, 44 are arranged at successive points along the

guides

37 and 38. The firstset'39, 40 is adapted to partially fold 'up the unslitted areas and is positioned along the guides 37 and 38 'at a point beyond that at which the guides release a'p'or'tion of the additional unslitted areas which were taken in by the

rollers

30 and 31. The release is. of course gradual from the feeding ends of the

guides

37 and 38 to their delivery ends, the same'being accomplished by the tapered formationof the guides. This operation will be clear from inspection of Fig. 7 and as will also be apparent from inspection of that figure, the folding up of the unslitted strips X is effected by the

rollers

39 and 40 while the bottom or midpoints of the strips X are maintained-in the general plane of the sheet, i. e. in alignment with the centers of the angled grooves G with the result that the strands S which are not engaged by the

guides

37 and 38 are partially opened up. It should be noted at this point that the initial opening operation here accomplished is brought about by a bending of the strands-S from the usual connecting bridges Z,'the said bending being in the nature of a flatwise and longitudinal swinging of each strand with respect to its connecting bridges Z in contradistinction to an edgewise separation of the strands in the same plane in which the bridges lie. That is, each strand is bent or swung from one end through an arc which lies in a plane substantially atright angles to the connecting bridges Z and, of course, to the legs of the grooves G. The former type of opening, i. e. that accomplished by the present apparatus subjects the strands and bridges to the least possible strains and therefore is advantageous in providing a stronger finished'product. 105 Note still further in connection with Fig. 7 that the strands S adjacent the unslitted strips are bent or opened with respect to the said unslitted strips in the same manner as the intermediate strands are bent or opened up with respect to 110 their connecting bridges Z. This is accomplished by the partial folding up of the unslitted strips, i. e. to 'a position in which the slitted areas as a 1 whole extend at substantially right angles therefrom. I

The second set of forming

rollers

43, 44 is positioned approximately at the ends of the

guides

37 and 38 and in view of the fact that the guides progressively engage less and less of the slitted areas at the sides of the angled grooves G,'additional strands S are released. These additional strands S are slightly opened up in the manner already described by the additional folding up of the unslitted areas X into the relatively high ribs, the same being accomplished by means of the rollers 43 and 44 (see Fig. 8). It should also be observed here again that the centers of the relatively high ribs and of the grooves G are still maintained (by the rollers and guides) in substantially the same plane.

The foregoing pre-expansion or pre-op6ning operation, it might be noted, should not be confused with the expanding operation proper, i. e. that accomplished by the diverging sets of :guides. This pre-opening operation prepares the blanks, so to speak, for the subsequent expanding operation by slightly forming or bending the strands in a manner which subjects them to the least possible strains, and'according to which the subsequent expansion or bending of the strands will continue along the same lines as shown in Figs. '9 and 10. It is also worthy of note that heretofore in this art great difliculty has been experiencedin producing lath by means of apparatus employing diverging guides without subjecting 'the strands of the mesh work to strains which at times even caused breakage during expansion and very frequently resulted in a weak finished article. The underlying cause of this difficulty is the fact that the diverging guides of an ex- 150 Sit '- still further reduced.

pander of the type in question tend to'open the strands edgewise in the general plane of the sheet and thus subject the connecting bridges to very great tearing strains. My invention, however, prepares the blanks, for expansion by diverging guides, in such a manner that the bending or opening up of the strandswill be carried out with a minimum of tearing strains to the bridges. Thus the apparatus of the present invention permits the use of an expander of the diverging guide type with its incident advantage of high speed production without sacrificing strength in the finished lath.

In continuing the discussion of the operation of the apparatus, it should be observed that the last set of

rib forming rollers

43, 44 deliver the lath blanks directly to the first set of diverging

guides

60, 61, the same being configured to engage and maintain the formation of the relative high ribs. When the forward edge of a blank has passed thru the first 'set of diverging guides, its ribs are engaged by the feeding rollers 66, 6'1 and as the blank advances thru the second set of diverging guides, it is engaged by the second set 5: of feeding rollers and so on progressively to the third and last sets, it being borne in mind, of course, that all of the feeding rollers 66 and 6'? are driven in synchronism'. At this point, several advantages of the particular type of expanding mechanism herein disclosed should be noted.

Firstly, thetotal length of the expander proper is much greater than that commonly provided, 1. e. substantially greater than the length of the blanks commonly used and substantially greater 3 than the length of expanders commonly employed in producing a fully expanded lath of a given width. This,of course, enables the guides to be positioned at a very small angle of divergence with the result that the strains to the strands are The small angle of divergence of the guides also permits the use'of feeding rollers mounted as shown and described herein, i. e. on shafts or axes of rotation which extend transversely of the guiding mechanism asa whole. Heretofore, when feeding rollers were employed in connection with diverging. guides the angle of divergence of the guides was such that the rollers had, of necessity, to be mounted individually on axes extending at right angles to the particular guides with which the pairs were associated. Stated in another way, as heretofore constructed, each pair of feeding rollers was mounted and arranged so that their gripping surfaces moved in the direction of feed of the blanks thru the particular guides with whichthe pair was associated. The complication in providing driving connections for feeding rollers mountedv in this manner is obviously very great.

I have completely obviated the difiiculties just noted by reducing the angle of divergence of the guides to a point which permits the use of sets of feeding rollers mounted for rotation on coinciding or parallel axes the same extending transversely of the expander guides as a whole. All of the upper or lower rollers in a rib engaging set may, therefore, be mounted on a single shaft. The driving connections necessary are, thereby, greatly simplified as is, also, the mounting of the rollers. I I

Still another advantage of the decreased angle of divergence of the expander guides is the decreased wear and tear to the guides'and feeding rollers in general. It is obvious that the feeding rollers must engage the blanks with a much greater pressure in expanders having a relatively great angle of divergence than in expanders in which the angle is diminished. It is also obvious that a greater angle of divergence subjects the guides to proportionately increased lateral wear.

The difiiculties which have been noted just above have been particularly troublesome in the manufacture of the so-called high rib lath by the diverging guide type of expander in view of the fact that the relatively high ribs must be almost constantly engaged either by guides or rollers throughout the entire length of the expanding mechanism in order to prevent the ribs from opening out or spreading during the expansion process and wherethe guides have a relatively greatangle of divergence the necessary continuous contact of the guides and rollers with the ribs of the blanks resulted in an amount of frictional resistance which was very detrimental to the efficient operation of themechanism. This difficulty ,is considerably ameliorated according to the present invention by lengthening out and thus reducing the angle of divergence of the expander guides.

In addition to the advantages already pointed out in connection with the construction of the guide members themselves it should be observed that the provision of the renewable tongue or knife member of each of the upper guides is advantageous as such knives may be replaced, when necessary on account of the wear, without renewing the entire guide member. This, of course, makes for economy in the maintenance of the apparatus and it is worthy of note that the knives may readily be made from standard strip steel stock by cuttingthe same into suitable lengths and machining the blank engaging edge and'ends. Still further an advantage resides in the fact'that the renewable knives are the parts of the-guides which are subject to the greatest wear., Thisflwould be apparent from inspection of Figure 9 or Figure 10 from which it will be seen that the contact end, therefore, thewear on the grooves of the lower guide members 61 is distributed not only on each side of the grooves but'alsothroughout a relatively large area on each of the said sides, whereas practically all of the wear to the upper guides will occur at the bottom edges of the knives 78. The construction,

therefor, makes provision for the renewal or'replacement of the parts which wear most rapidly. The advantages incident'to theuse of steel and cast iron in making the knives and the guide bodies have already beennoted.

The operation of the delivery mechanism in cluding the guides 87 and 8S and therollers 94 and 95 is quite obvious, the said guides and rollers merely serving to straighten and even'up the ribs as they are delivered fromthe last set of feeding rollers 66 and from the apparatus. A portion of a completed blank is illustrated in Figs. 14 and 15 from which it will be observed that the mesh work takes the 67 and to deliver the blanks form of av plurality of'inclined diamond-shaped meshes on either side of relatively narrow un- I slitted strips, the latter originally constituting the central portion of the angled grooves G '(see Figs. 12 and 13). It will also be noted that the diamonds are inclined in opposite directions on each side of the said relatively narrowfunslitted strips and that the strengthening ribs B1 are interposed between each pair of mesh work sections.

In conclusion attention should again be directed to the simplicity of the driving' mechanism panding mechanism including guide devices with means for feeding the blanks therethrough, and the guide devices last mentioned being arranged to diverge from each other in the direction of feed of the sheets through the apparatus, whereby to subject the sheets to an opening pull in a direction lying substantially within the original plane of the sheets.

HERBERT K. BAKER.

iso-

CERTIFICATE OF CORRECTION.

Patent No. 1,972,179. September 4', 1934.

, HERBERT K. BAKER.

Ilt ishereby certified that error app ars in the printed specification ofth'e abovenumbered patent requiring correction as follows:' Page 6, iitte-l27 ,-c-l aim l1, strike out the WOI'dS SEiWEd blanks, and that the said Letters Patent should be read with this correction therein that the same may conform to the record-of the case in the Patent Office.

Signed and sealed this 2nd day of October, A. D. 1934.

(Seal) Acting Commiss'ioszet of Pawns.