US2921454A - Knitting machine - Google Patents

Description

4 Sheets-Sheet 1 Filed Nov. 21, 1956 INVENTOR.

THEODORE. E. SHASTANY BY flw hv ATTO RNEYS Jan. 19, 1960 1'. E. SHASTANY KNITTING MACHINE 4 Sheets-Sheet 2 Filed Nov. 21, 1956 FIG. 5.

INVENTOR.

THEODORE E. SHASTANY ATTORNEYS Jan. 19, 1960 T. E. SHASTANY KNITTING MACHINE Filed Nov. 21, 1956 THEODORE E. SHASTANY Y L4 :21

I ATTORNEY v WMnW-HIHH W. W KE NLH D S K T TNSS ll II l iii gamma Jan. 19, 1960 -r. E. SHASTANY KNITTING MACHINE 4 Sheets-Sheet 4 Filed Nov. 21, 1956 INVENTOR. THEODORE E. SHASTANY Zdf V,

ATTORNEYS:

United States PatentQ KNITTING MACHINE Theodore E. Shastany, Laconia, NH, assignor to Scott & Williams, Incorporated, Laconia, N.H., a corporation ofMassachusetts Application November 21, 1956, Serial No. 623,595

6 Claims. (Cl. 66-108) This invention relates to knitting machines and particularly to the knitting of welts in sheer ladies stockings.

In knitting seamless ladies stockings, one of the major problems, particularly since fine gauge fabric has become popular, has been to knit the welt loose enough to fit properly above the knee and still have all of the stitches retain uniform size and shape. In order that the ankle of the stocking may be sumcicntly narrow to fit properly, a maximum number of needles are spaced about the cylinder and knit fairly tight stitches. However, since the required width of the welt fabric above the knee is approximately 50% greater than the ankle width, the stitches are necessarily much larger.

Due to these large stitches of relatively light or fine yarn, there is less of a locking condition present during their formation, and at times a stitch may be sufiiciently distorted as various parts of the needle pass through it that it will fail to return to its proper shape and size at the end of its knitting cycle. This condition may be somewhat exaggerated when the yarn used is of a type such as nylon, which under certain conditions has a tendency to take and retain a set.

When distortion occurs in one stitch, a certain amount of robbing of yarn from adjacent stitches usually takes place which causes them also to be deformed to some extent and the result is an irregular cluster of stitches variously known in the trade as a draw stitch, crow foot, hen track, or the like. While the deformed stitches do not usually impair the wearing qualities of a stocking, they are unsightly and may result in the stocking being classed as a second and sold at a reduced price.

The distorted stitches. are particularly troublesome in loose fabric of so-called turned welts in which the initial courses are taken from the needles and held by instruments in a dial during the knitting of a loop of fabric and then returned to the needles to join other stitches as shown in the patent to R. W. Scott No. 1,232,958. Due to the holding of the first courses, the stitches of the loop of fabric cannot be controlled by a takeup and several methods have been tried to apply tension, in-

cluding the use of air blasts, but without marked success.

One of the reasons for knitting the welt exceptionally loose isdue to shrinkage which takes place in nylon or yarns of similar type during finishing operations, and a method which permits the knitting of relatively smaller stitches by the use of preshrunk yarn is described in the patent to B. J. Faucette No. 2,396,166. While this method is satisfactory, it is desirable to secure satisfactory results, if possible, by mechanical means, and it is the general object of the present invention to provide such means, and in cases where welts of extreme width are required, to combine the method of using preshrunk yarn, as disclosed in Patent No. 2,396,166, with the mechanical means of .the present invention.

It has been found that by properly moving the sinkers, a welt can be produced having alternate groups of loose wales and tight ,wales. The loose and tight wales proice vide a ribbed appearance and in addition to good appearance provide a welt with more stretch than is possible by knitting with loose stitches which are not sufficiently loose to give rise to objectionably formed stitches and the so-called draw stitches, crows feet, hen tracks, etc.

The'apparatus involved will be described as applied to a single feed hosiery machine such as shown in the previously mentioned Scott patent for making a ladys stocking and having a loose upper portion or welt, and will also be briefly described as applied to a similar machine having two feeds, but it will be equally effective in hosiery machines having more feeds, or in any knitting machine where large stitches of relativelylight yarn would otherwise be required to provide a high degree of stretch.

The invention is not only limited to the production of straight ribs but may also be employed in connection with the use of alternate S and Z twist yarns causing the wales to slope first in one direction, then the other thereby producing bands of alternately sloped ribs in the welt of the stocking.

The foregoing and other objects of the invention re-- lating particularly to details of construction and operation of apparatus embodying the invention will become apparent from the following description read in conjunction with the accompanying drawings in which:

Figure 1 is a development of the knitting cams of a machine embodying the invention, the development being viewed looking outwardly from the axis of the needle cylinder,

Figure 2 is a plan view of the sinker cam ring of the knitting machine as viewed from above showing the regular cams as well as those which are specially provided in accordance with the invention;

Figure 3 is a fragmentary section taken on the plane the trace of which is indicated at 3-3 in Figures 1 and 2, this section showing the needle cylinder, cylinder top, sinker ring, sinker cam ring, a short butt sinker and a long butt sinker together with a needle and sinker in their relative positions during the time the needle remains at tuck height;

Figure 4 is a similar fragmentary section taken on the plane the trace of which is indicated at 44 in Figures 1 and 2 and showing the position of a sinker in relation to a needle when the sinker has been moved fully inwardly by a presser cam after the needle has reached its extreme latch-clearing height;

Figure 5 is a similar fragmentary section taken on the plane the trace of which is indicated at 5-5 in Figures 1 and 2 and showing a needle and sinker at the time the sinker cam has just moved the sinker into position to cast a stitch from the needle;

Figure 6 is a similar fragmentary View taken on the plane the trace of which is indicated at 6-6 in Figures 1 and 2 and showing a needle and sinker at the time when the latch is being opened by a stitch as the needle is being raised;

Figure 7 is a diagram showing the fabric produced in accordance with the invention involving a straight ribbed fabric;

Figure 8 is a diagram showing the fabric produced by the use of alternately twisted yarns; and

Figure 9 is a view generally similar to Figure 1 but showing a development of the jack and knitting cams of a two feed machine as viewed looking outwardly from the axis of the needle cylinder.

Referring first to Figures 1-6, inclusive, there are shown certain parts of a single feed machine as are particularly involved in the accomplishment of the objects of the present invention. For further details of such a Patented Jan, 19, 1960 3 machine, reference may be made to the Scott patent referred to above. I

The machine comprises latch needles 2 carried by a needle cylinder 4. A sinker ring 6 is slotted as indicated at '8 to mount sinkers 9 and'10 for radial sliding movements, the inner portions of the sinkers being guided in conventional fashion by the cylinder top 11. A sinker cam ring indicated at 12 is provided with a cam 14 which serves to move sinkers outwardly, and with the usual earns 16 and 18. The cam 18 serves to move the sinkers inwardly during normal forward knitting, and the cams 16 and 18 are active during reciprocatory knitting, cam 18 acting when the rotating is in the forward direction and cam 16 acting when the rotating is in the reverse direction. Additionally there are provided the cams 20 and 22 in accordance with the present invention serving for additional control of the sinkers 10.

The sinkers 9 are normal sinkers having butts 23 and the sinkers are provided with butts '25 slightly higher than the butts 23 of the sinker 9. All of the earns 14, 16 and 18 act on the sinker butts 23 and 25 but the earns and 22 act only on the high butts of the sinkers 10. In the embodiment of the invention shown and described herein there are provided two adjacent high butt sinkers and two adjacent low butt sinkers in alternate arrangement around the sinker ring.

The'sinker ring is grooved at 24 to receive a spring band 26 which serves to urge the sinkers inwardly in yielding fashion. As will hereafter appear, the action of this spring band is limited by the inner bounding surface of the groove 24: i.e., the inward motion of the .springis thus limited and the sinkers move further inward only as a result of cam action.

The cam 16 is secured to the sinker cam ring by screws 28 and 30, whilethe cain 18 is secured to the sinker cam ring by screws 36 and 38. These cams are consequently immovable with respect to the sinker cam ring during operation of the machine.

Presser cam 20 is pivoted on a screw stud 32 carried by the sinker cam ring and has its inward movement adjustably limited by engagement of an eccentric stop 34 carried by the cam with the outer edge of the sinker cam ring. Cam 22 is similarly pivoted to the sinker cam ring on a screw stud 40 and is provided with an adjustable eccentric stop 42 which limits its inward movement by engagement with the edge of the sinker cam ring. The cams are respectively urged inwardly by the leaf springs 35 and 43 carried by upright shafts 37 and 45 which are subject to control from cams on the main drum of the machine, the springs acting on the cams to urge them inwardly during welt formation, though the cams may be so urged thereafter.

Referring now to Figure 1, the cams provided for action on needle butts comprise the forward and reverse stitch cams 44 and 46, the center cam 48, the raising cams 50, 52, 53 and 54, and the clearing cam provided at 56 on the reverse stitch cam. Various other cams which take part in phases of the knitting not of concern herein are illustrated and it will, of course, be understood that the machine is provided with the usual pickers for the formation of heels and toes, these not being shown. Associated with the needles in their slots in the needle cylinder are intermediate jacks 58 and pattern jacks 60 which, however, take no part in the phases of operation to which the present invention is directed, and accordingly these jacks and their operations are not detailed. Yarns are fed to the needles from the usual feeding fingers 63 of which one is indicated in action at 62, the yarns being fed to the needles from a conventional throat plate indicated at '64. During the formation of a stocking welt, the needle butts follow the path indicated at'66 in Figure 1, the hook ends of the needles following the corresponding path 68.

For clarity,the positions of the sinker operating cams are indicated at 18, 20 and 22, there being indicated only the active portion of the first of these cams.

Operation of the described mechanism is as follows:

Considering first the movements imparted to the needles, the cycle may be considered as beginning at the position indicated at A in Figures 1 and 2. At this position the needle butts are just beginning their movement down center cam 48, whereby each needle is caused to take yarn and draw it to a measured loop over the platforms of adjacent sinkers as it is lowered by stitch cam 44. The lower end of stitch cam 44 provides a close raceway in association with the level portion '49 of the cam therebelow, and this arrangement causes the needle to draw a definite amount of yarn and to hold it accurately against robbing by succeeding needles as they draw their loops and until the previous stitches have been cast from the needles. The lowermost position of the needle'thus achieved at B is illustrated in Figure 5. The needle is then raised slightly by cam rise 50 to the position indicated at C to relieve the tension on the new loop. The needle then rises over the next cam which includes the relatively rapid rises 52 and 54 and a slight rise at 53 between the positions indicated at D and E. The first rise at 52 to the position approximately indicated by D brings the needle to the level indicated in Figure 6 where the loop begins to open the latch. Immediately following this is the gentle rise over the cam portion 53 which completes opening of the latch. Then the needle rises at 54, position E, and winds up at tuck level where it remains, as indicated in Figure 3, until it reaches the'rise 56 on-the reverse stitch cam by which itis raised to latch clearing height at position F. The needle thenpasses positions indicated at G and H to approach the center cam 48 and complete the described cycle. The position of the needle between F and A is that illustrated in Figure 4 which is-a section taken at the position G. The needle movements which have just beendescribed are conventional, and the present invention is particularly concerned with the sinker movements which accompany the needle cycle.

At the beginning of the cycle at A, the sinkers have been withdrawn by the sinker cam 14 to permit the yarn to be drawn by the needle hook past the sinker nebs and over the platforms of adjacent sinkers.

At the position B a close raceway is formed between the cams 14 and 18 to prevent possible overthrow of the sinkers or chatter which might tend to cause stitches to vary in size. At position B each of the sinkers 9 and 10 is moved inwardly by knock-over cam 18 to a position which will cause the completed stitch to be back of the rising needle. The position attained by the sinker is that illustrated in Figure 5.

Following the position B each of the sinkers is held substantially in a constant radial position until it reaches the position C. At this point, the contour of the sinker presser cam 22 crosses that of the cam 18 and the sinkers 10 having high butts are gently moved inwardly until they reach the position D when they are located as illustrated in Figure 6. The sinkers 9 having low butts are moved outwardly by stitch tension as the cam 18 recedes until further outward movement of the sinkers is restrained by the spring band 56. It will be noted that the spring band is restrained from inward movement by engagement of the inner wall of the spring groove 24.

Cam 22 acts as an unyielding cam, having its position fixed by the setting of stop 42, even though it is held inwardly by spring 43, the spring being a strong one capable of resisting any outward forces exerted by the sinkers under yarn action. The contour of cam 22 then recedes following position D and under the tension of the stitch each sinker 10 may gradually move outwardly until it reaches location E at which time it engages-the spring diagonally across the fabric.

band 26 and maintains a position beyond position B such as that illustrated in Figure 3.

The position attained is then normally maintained by each of the sinkers until it reaches location F. At this location the high butt sinkers begin to move gradually inwardly under the action of the sinker presser cam 20 (which like the cam 22 is essentially unyielding) until the location G is reached where the sinkers 10 assume the position illustrated in Figure 4, the sinkers 10 again being located radially inwardly of the positions of the sinkers 9 maintained by the spring band 26.

Beyond location G and to location H the sinkers 10 are released by the sinker presser cam and may move outwardly under the tension of the yarn, this movement being limited by their engagement with the spring band when they assume the same position as is assumed by the lower butt sinkers 9 in this location. Beyond position H the sinkers engage the cam 14 whereby they are drawn to the position mentioned at the beginning of the cycle, the spring band yielding under the positive action of cam 14.

The foregoing structure provides for the production of successive needle loops of uniform size and for the production of sinker loops inwhich the loops drawn over short butt sinkers are normal loops and in which the loops drawn over long butt sinkers are long or loose loops. After the stitches are cast off and natural stitch adjustment occurs among the loops, the needle loops on each side of the large sinker loops receive yarn from the sinker loops thus giving rise to three enlarged needle loops. In Figure 7, at 140, there is indicated generally a needle wale composed of long or loose stitches. There follows in the direction of knitting a row of sinker loops 142, a needle wale 144, a row of sinker loops 146 and a needle wale 148. Each of these needle wales is formed of long or loose stitches and the sinker loops 142 and 146 are formed over high butt sinkers and are loose loops. There follows a row of sinker loops 150, a needle wale 152 and a row of sinker loops 154. The needle wale is a normal tight stitch and the two rows of sinker loops 154 and 150are formed over normal or low butt sinkers which produce tight loops. Thus the two slack or high butt sinkers followed by the two normal or low butt sinkers give rise to three loose wales with loose intermediate sinker loops which assume a sunken position and one tight wale with tight adjacent sinker loops which assumes a raised position. It will be evident that this formation is repetitious and produces a fabric having a ribbed appearance but not truly ribbed fabric, all of the loops being concatenated in the same direction.

A modification of the invention is shown diagrammatically in Figure 8. knitting yarn will cause knitted stitches to leanor be deformed in one direction or the other according to the direction of twist. If a plurality of courses are knit with a yarn having a high degree of twist in only a single direction the result will be wales which tend to slope If a group of successive courses are knit with a yarn twisted in one direction and then a group of successive courses are knit with yarn twisted in the opposite direction the wales will slope first in one direction in the first group of courses and then in the other directionin the other group of courses causing a zigzag or herringbone type of appearance.

In Figure 8 there is shown at 164 a plurality of courses knit in accordance with the invention with a twisted yarn twisted in a first direction, e.g., an S-twist yarn, giving rise to groups of loose or sunken wales 160 spaced by tight or raised wales 162 sloping in a first direction. At 166 there is shown a plurality of courses knit witha yarn twisted in the opposite direction, e.g., a Z-twist yarn, in which the adjacent groups of loose or sunken wales and tight or raised wales slope in the opposite direction from those shown in the courses 164.

It is well known that the twist of a At 168 there is shown a plurality of courses knit with the yarn twisting in thesame direction as was the yarn employed in the knitting of,courses 16 4 and at 170 the yarn is the same as that employed for the courses 166. The two oppositely twisted yarnsare fed to the needles by selectively moving into action the usual yarn feeding fingers providing for feed of variously required yarns and indicated generally at 63 in Figure 1. Alternately, there may be employed a single yarn having successive lengths alternately twisted as S-twist and Z-twist yarns. These lengths may extend for several yarns and are each of sulficient length toprovide a suitable number of courses of knitting to produce herringbone appearance in the finished fabric asdiagrammed in Figure 8. Such a fabric provides not only for additional stretch and the avoidance of the so-called draw stitches, crows feet, hen tracks, etc., but also provides a welt having a particularly desirable and attractive appearance.

Figure 9 illustrates the application of the invention to a two-feed hosiery machine. The general arrangement ofthe cams is similar to that shown in the patent to J. J. McDonou gh No; 2,576,962, except that the needles are shown as being raised from tuck to clear height at one feed, and from just beyond the bottom of the central stitch cam to clearing height at the other feed by intermediate jacks rather than by needle butts. The latch needles 2 are associated with sinkers 9 and 10 in an arrangement which is substantially identical with that illustrated in Figures 3 to 6, inclusive, and accordingly specific reference tothese elements and their mountings will not be repeated. Intermediate jacks 70 and pattern jacks 72 are provided the latter being of tilting type as used in machines of this character. Referring first to the control of the pattern jacks, these jacks have their lower ends tilted outwardly, as they enterthe cams from the right-of Figure 9, by a cam 74 pressing on their upperends. to cause the notch 75 of each jack to engage and ride upwardly over cam 76. Cam 78 then engages and depresses the shoulder 80 of each pattern jack, and the jacks are further lowered by the action of a cam 82 on their butts 84 bringing them to the level at which they enter the right of Figure 9.

The intermediate jacks 70 are provided with butts 87. Through the action of the pattern jacks they are raised at the location of cam 76 to a level above the cam 86 and are raised by the rise 88 of this cam, being then lowered by cam 90. Cam 92 again raises the intermediate jacks and they are depressed by cam 94 to their initial level. 1

The butts 96 of the needles 2 enter the cams at tuck level along the path 98. Asthe intermediate jacks rise over cam 88, the needles are pushed upwardlyv as indicated at 100 to clearing height and pass at this height over the reverse stitch cam 102 at the first feed. They are then depressed by the cam 104 and then by the first feed forward stitch cam 106 to take yarn fed by the finger 108 and passing from the throat plate 110. The stitch cam 106 moves the-butts 96 to their lowermost level 114 whereupon they are raised slightly by cam 116 to relieve tension on their stitches.- They are then raised to clearing height at 118 by the rise of the intermediate jacks over cam 92, are slightly depressed by cam 120 and then engage and are lowered by the second feed stitch cam .122 taking yarn fed by a finger 124 and from a throat plate 126. After reaching their lowermost position under the lower end 128 of stitch cam 122, they are slightly raised at 130 and are then further raised by the successive slopes 132, 134, and 136 of a raising cam, finally arriving at tuck level in the path 98.

It will be evident from the foregoing brief description of the needle path that the needles, in the case of this two-feed machine, pass twice in a single revolution of the needle cylinder through phases corresponding to those involved in the single feed machine and illustrated in The tilting action serves 7 Figure 1. Since the duplicated needle movements are essentially the same-asthose-involvedin the'single feed machine "they will not be further described.

There are fllustrated in' Figure 9 the varioussinker operating cams which have the same functions as those'in Figure 1, and may be similarly mounted andco'ntrolled, but are duplicated at-the'two feeds. At the first feed the cams 18', 22" and '20 correspond, 'respectively,'to the earns 18, 22 and 20' of Figure 1. At the second feed cams 18", 22" and 20 correspond, respectively, to the cams 18, 22 and 20 of Figure 1. Additionally, there are indicated in Figure 9, in association with the first feed, the locations B, C, D, E, F, G and H corresponding to the respective unprimed lettered positions indicated in Figure 1 while inassociation-withthe second feed there are indicated the positions B", C", D", E, F, G and H" which also correspond, respectively, to the unprimed lettered locations of Figure 1. Without going into detailed discussion of theseloc'ations, it may be stated that respectively thereat there occur the same relationships of the sinkers and needles as were described in detail in connection with the'single feed machine, and the sectional views Figures 3 to 6, inclusive, would serveto illustrate the sinker operations involved at each of the two feeds in Figure 9. It will accordingly be evident that the same controls of stitch formation are involved in the two-feed machine as in the single feed machine. The sole difference which may be noted is that the rise to clearing height alongpath 118 following the lowering of the needles by stitch cam 106 is accomplished in a continuous movement rather than in stepped movements as in the case of the second feed in Figure 9 and in the case of the single feed in Figure 1. While this continuous rise of the needlesoccurs, the sinker actions in control of the stitches are substantially identical.

It will also 'be'evident that the invention is applicable to machines involving more than two feeds, there being provided in association with each of the feeds the same types of sinker controls. In all cases the stitches are properly controlled and formed with the elimination of the objectionable distortions discussed above.

It should be noted that the fabric shown in Figure 7 results from the use of a normal low twist yarn fedin a single or multiple feed machine. Alternatively, for example, in a two-feed machine, if one feed supplies 8 high twist yarn and the other feed Z high twist yarn, the resulting appearance will be substantially that of Figure 7, exceptthat stitches of alternate courses will slant in one direction while those of the intervening courses will slant in the opposite direction, but a higher degree of stretch will be provided. The arrangement shown in Figure 8 can be made not only'by the alternately twisted yarn previously mentioned or by alternate feeds of S-twist and Z-twist yarn but also by a multi-feed machine providing S-twist yarn at all of the feed stations for a plurality of counses followed by the feeding of Z-twist yarns at all of the feed stations.

It will be further evident that various combinations of long butt and short butt sinkers may be employed al though the alternately arranged two long butt and two short butt sinkers as disclosed herein provides a most desirzlrble arrangement in connection with knitting a stocking we t.

What is claimed is:

l. A knitting machinecomprising a cylindrical needle bed, latch needles movable therein, sinkers associated with said needles, a spring band for urging the sinkers inwardly, cams for imparting a knitting wave to said needles, means for advancing sinkers to a radial position to move loops which have been cast oif beyond the hooks of rising needles, means for further advancing spaced groups of adjacent sinkers as the needles rise for elongating groups of stitches and correspondingly shortening Stitches en aid g oups, and means restraining said springband from urging said sinkers inwardly as far as they are advanced by the last mentioned advancing means.-

'2.-'A-knitting'machine comprising a needle bed, latch needles movable therein, sinkers associated with said needles, cams for imparting a knitting wave to said needles; means for advancing sinkers to a position to move loops which have been cast off beyond the hooks of rising needles, means for further advancing spaced groups of adjacent sinkers as the needles rise and latch opening occurs for elongating groups of stitches and correspondingly shortening stitches between said groups, and means for again advancing said spaced groups of sinkers while the stitch loops rest upon needle shanks below their latches'for elongating said groups of elongated stitches and correspondingly shortening said stitches between said groups.

3. A knitting machine comprising a cylindrical needle bed, latch needles movable therein, sinkers associated with said needles, a spring band for urging the sinkers inwardly, cams for imparting a knitting wave to said needles, means for advancing sinkers to a radial position to move loops which have been cast off beyond the hooks of rising needles, means for further advancing spaced groups of adjacent sinkers as the needles rise and latch opening occurs for elongating groups of stitches and correspondingly shortening stitches between said groups, means for again advancing said spaced groups of sinkers while the stitch loops rest upon needle shanks below their latches for elongating said groups of elongated stitches and correspondingly shortening said stitches between said groups, and means restraining said spring band from urging said sinkers inwardly as far as they are advanced by the two last mentioned advancing means.

4. A knitting machine comprising aneedle bed, latch needles movable therein, sinkers associated with said needles, cams for imparting a knitting wave to said needles, means for advancing sinkers to a position to move loops which have been cast off beyond the hooks of rising needles and means for further advancing spaced groups of adjacent sinkers as the needles rise and substantially following the attainment by the needles of the ends of their stitch drawing movements for elongating groups of stitches by robbing yarn from stitches between such groups, thereby to shorten the latter.

5. A method of knitting on a machine comprising a needle bed, latch needles movable therein, sinkers associated with said needles, cams for imparting a knitting wave to said needles, and means for operating sinkers, comprising advancing sinkers to a position to move loops which have been cast off beyond the books of rising needles, further advancing spaced groups of adjacent sinkers as the needles rise for elongating groups of stitches and correspondingly shortening stitches between said groups, and during the aforementioned knitting feeding yarn having a high degree of twist in one direction for a plurality of courses of knitting and feeding yarn having a high degree of twist in the opposite direction for a succeeding plurality of courses of knitting.

6. A method according to claim 5 in which said further advancing of sinkers takes place as latch opening occurs, and in which said spaced groups of sinkers are also advanced while the stitch loops rest upon needle shanks below their latches.

References Cited in the file of this patent UNITED STATES PATENTS 697,078 Ellis Apr. 8, 1902 2,337,153 Cloutier Dec. 21, 1943 2,703,970 Reymes-Cole et al Mar. 15, 1955 2,727,374 Page Dec. 20, 1955 FOREIGN PATENTS I 221,686 Great-Britain Sept. 18,1924

Images