US2716878A

US2716878A - Two part knitting machine needle assembly

Info

Publication number: US2716878A
Application number: US320685A
Authority: US
Inventors: Joseph L Morris
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-11-15
Filing date: 1952-11-15
Publication date: 1955-09-06
Anticipated expiration: 1972-09-06

Description

Sept. 6, 1955 J. MORRIS 2,716,878

TWO PART KNITTING MACHINE NEEDLE ASSEMBLY Filed Nov. 15, 1952 7 Sheets-Sheet l FIG. 4. FIG. 4b. f *1 FIG. 4a.

INVENTOR JOSEPH L. MORRIS,

ATTORNEY Sept. 6, 1955 J. 1.. MORRIS 2,716,878

TWO PART KNITTING MACHINE NEEDLE ASSEMBLY Filed Nov. 15, 1952 7 Sheets-Sheet 2 00' /"'''t0 f c9 I 5 LL CO I I 9 I f I N N I z I I i 93 I /N I I I I INVENTOR JOSEPH 1.. MORRIS,

ATTORNEY p 1955 J. L. MORRIS ,7 6,878

TWO PART KNITTING MACHINE NEEDLE ASSEMBLY I Filed Nov. 15, 1952 '7 Sheets-Sheet 3 3-2 :zzzz: .09 38 Fl G. 9 34 FIG. IO.

FIG.II.

INVENTOR JOSEPH 'L. MORRIS,

Sept. 6, 1955 J. MORRIS 2,716,878

TWO PART KNITTING MACHINE NEEDLE ASSEMBLY Filed Nov. 15, 1952 '7 Sheets-Sheet 4 INVENTOR l JOSEPH L. MORRIS ATTORNEY FIG. l5.

Sept. 6, 1955 J. L. MORRIS 2,716,878

TWO PART KNITTING MACHINE NEEDLE ASSEMBLY Filed Nov. 15, 1952 7 Sheets-Sheet 5 FIG.I7.

' 52 FIG. l8

39 I INVENTOR FIG. 22. K JOSEPH L. MORRIS,

A BY

ATTORNEY Sept. 6, 1955 J. L. MORRIS 2,716,878

TWO PART KNITTING MACHINE NEEDLE ASSEMBLY Filed Nov. 15, 1952 7 Sheets-Sheet 6 FIG. 23.

FIG.24.

FIG.25.

INVENTOR 43 JOSEPH L. MORRIS,

BY 42 J ATTORNEY p 6, 1955 J. L. MORRIS 2,716,878

TWO PART KNITTING MACHINE NEEDLE ASSEMBLY Filed Nov. 15, 1952 7 Sheets-Sheet 7 FIQ, 28.

INVENTOR JOSEPH L. MORRIS,

ATTORNEY Patented Sept. 6, 1955 TWO PART KNITTING MACHINE NEEDLE ASSEMBLY This invention relates to improvements in two piece latchless knitting machine needles.

Broadly, it is an object of the invention to provide a latchless knitting needle which will do anything done by a latch needle and which will travel but half the distance so that the loops will be formed and cast-off with less cam action.

Another object of the invention is to provide a latchless knitting needle which will permit more feeds in a given space in the machine.

At the present time two piece nedles have movements in the same plane in relation to each other. Such needles have a knitting hook which is too small in relation to the gauge of the knitting machine. In order to increase the size of the knitting hook, it is necessary to increase the height of the needle shank. However, increasing the height of the raised needle shank also provides a problem since the loops slide up on the top of the raised needle shank during the knitting cycle. I have, therefore, provided a machine knitting needle which permitsthe use of a larger knitting hook and a lower raised needle shank without interference with the other functions of the needle, as will be hereinafter more fully explained. The top of the knitting hook portion may be at the same horizontal level as the raised shank portion or may be higher than said raised shank portion.

To clarify the above paragraph in greater detail, it is well known that various two piece needles have but one reciprocating movement for each needle member, where both reciprocating movements are parallel with and in relation to the horizontal plane of the needle assembly, where the horizontal plane is parallel with the longitudinal plane of a dial, cylinder or fiat bed needle slot, as the case may be. It is also well known that grooves in two piece needle assemblies are parallel with the longitudinal plane of the needle assembly. The undesirable features of these and various other needle assemblies are that the raised needle shank is always higher than the top of the knitting hook as no provisions are made to raise the loop from the raised shank vertically at 90 degrees in order to clear the top of a larger knitting hook. Another undesirable feature is feeding yarn into the smaller hooks. Various attempts have been made to solve the problem by various unsatisfactory lever, shoulder, one inclined cam formation, one built up formation, pivoting, frictional retardation, tilting, rocking and bending actions in various combinations, and as far as I know none of these modifications have provided an exact, positive bodily reciprocating movement to one needle member, vertically at 90 degrees to the longitudinal horizontal plane of the needle assembly, simultaneously with a longitudinal horizontal reciprocating movement of the other needle member. I have, therefore, provided a two piece needle assembly that eliminates the various unsatisfactory modifications, and have further provided an exact positive bodily reciprocating movement to one needle member exactly vertically at 90 degrees to the longitudinal horizontal plane of the needle assembly, simultaneously with a longitudinal horizontal reciprocating movement of the other needle member, which further permits the use of a lower raised shank and a larger knitting hook. This is made possible by the activating diagonal groove in the side of one of my needle members and will hereinafter be more fully explained.

A further object of the invention is to provide a needle assembly which will permit the cast-off member additional and desirable reciprocating movements not possible by other two piece needles.

Still another object of the invention is to provide a two piece needle assembly which will permit the castoff member to move bodily vertically or become elevated and further permit a simultaneous compound angle reciprocating movement in relation to the plane of the knitting hook member and any combination of such movements as will be more fully explained hereinafter.

Another object of the invention is to provide a two piece needle assembly which will permit the cast-off member to reciprocate diagonally at about an 8 degree angle in relation to the longitudinal horizontal plane of the needle assembly While the other needle member is prevented from reciprocating, as will hereinafter bemore fully explained. It is to be understood that the 8 degree angle will be variable depending on the gauge of the needle and other factors.

Another object of the invention is to provide a two piece needle assembly which will permit the cast-off member to recpirocate in an involute or arcuate movement, simultaneously with a horizontal reciprocating movement of the other needle member, as will hereinafter be more fully explained.

. A further object of the invention is to provide a two piece needle assembly which will permit the cast-off member to spread the loop and elevate the loop over another needle for the purpose of transferring the loop from one needle to another needle, by additions to the cast-off member as outlined in this application.

For a fuller understanding of the nature and objects of the invention, reference is bad to the following detailed description in connection with the accompanying drawings, in which:

Fig. 1 is an enlarged side elevation of my improved knitting hook showing an activating diagonal groove.

Fig. 2 is a side elevation of a well known and commonly used latch needle, the rear end being broken away.

Fig. 3 is a side elevation of the front end of the castoff member and knitting hook of a two piece needle now commonly used, the rear portions being broken away.

Fig. 4 is a sectional view of one form of groove in the knitting hook and the corresponding cast-off membar which slides in and is also activated by such groove. Figs. 4a and 4b are variations of same.

Fig. 5 is a side elevation of the cast-01f member.

Fig. 6 is an enlarged top view of the needle showing the points of the knitting hook and cast-off member.

Figs. 7 and 8 are enlarged top views of the needle showing modified cast-01f members for spreading loops.

Figs. 9 and 11 are side elevational views showing the needle assembly set in a dial.

Fig. 10 is a partial sectional view of a cylinder.

Figs. 12, 13 and 14 are side elevational views showing various movements of my needle.

Fig. 15 is a diagram to establish a permanent horizontal plane in order to eliminate the confusion caused by the various angles and vertical, diagonal and horizontal references that are necessary to clarify the various movements. The large open arrow 10 represents a horizontal plane, and is parallel with the longitudinal plane of a dial, cylinder or flat bed needle slot as the case may be. Since one member of my needle assembly, the knitting hook, has only one reciprocating movement which is also parallel with the longitudinal plane of the needle slot, the open arrow will also represent the horizontal plane of the needle assembly and the one horizontal reciprocating movement of the knitting hook. The

arrows

9, 12 and 14 represent three reciprocating movements of the cast-off member and show the relation to a horizontal plane as well as relation to the reciprocating movement of the other needle member. Arrow 9 represents a horizontal reciprocating movement of the castolf" member in relation to the horizontal reciprocating movement of the knitting hook 10. Arrow 12 represents a diagonal reciprocating movement of the cast-off member in relation to the horizontal plane of the knitting hook 10. Arrow 14 represents the vertical reciprocating movement of the cast-cit member at 90 degrees vertical in relation to the horizontal reciprocating movement of the knitting hook 10.

Figs. 16 to 22, inclusive, are side elevational views of the ends of the cast-off member and knitting hook of my needle showing a complete cycle of knitting which may be varied.

Figs. 23 and 24 are side elevational views of the ends of the cast-off member and knitting hook of the needle showing the knitting of a tuck stitch.

Fig. 25 is a side elevational view of my needle showing the position of the cast-off member in relation to the knitting hook for the transfer of the loop to another needle in a cylinder.

Fig. 26 is a side elevational view of my needle mounted in the dial shown in section, in relation to other parts of the knitting machine to show the position of the parts for transferring loops from one needle to another in a cylinder.

Fig. 27 is a modification of my needle assembly in side elevation showing a transposition of the activating diagonal groove wherein the movements of the knitting hook are transferred to the cast-off hook and vice versa.

Fig. 28 is a side elevational view of still another medification showing an arcuate movement of the respective parts of the needle providing an clevational movement of the cast-otf member.

Referring to the drawings, the figure shown in Fig. 1 represents what is hereinafter referred to as a knitting hook 51. This knitting hook is activated by conventional cams acting on butt 18 at the edges and i6 and also at the back edge 17 of the needle. The butt 18 may be positioned in various places along the knitting hook and the total length of the knitting hook may be varied as required. The size of the knitting hook portion 4 will be about the same as standard gauge sizes now used on latch needles. The height of the raised shank 5 will be about the height of the outside diameter of the hook portion 4 or less, as required. The knitting hook has an activating diagonal groove 19 as shown. This diagonal groove 19 of the knitting hook is about one-half the thickness of the needle in order to receive the second part of the complete needle. The degree of the angle of the diagonal groove 19 may be varied as shown in Figs. 4a and 4b, Fig. 4 being the preferred form of the diagonal groove.

In order to point out the functions of the knitting hook Fig. 1 in greater detail, the raised shank 5 tapers as shown at 65 toward the hook portion 4 where with my needle it is possible to increase the diameter of the hook portion 4 and lower the height of the raised shank 5 by increasing the angle 20 of the diagonal groove 19. The knitting hook has a step base where the rear base 66 is in the same horizontal plane and lower than the front base 67 under the raised shank 5 and hook 4, with an activating diagonal groove 19 in the side where the parallel edge surfaces 61 and 62 form two parallel activating cams, or the knitting hook may be composed of two detachable parallel activating needle body cams 63 and 64 where the. parallel edge surfaces 61 and 62 form an activating diagonal groove 19. The knitting hook will have one horizontal reciprocating movement as shown by arrow 10 in Fig. 15 at such times when machine cams are arranged to reciprocate the knitting hook; at other times the knitting hook will be prevented from reciprocating, and at other times the same reciprocating movement will be at variable speeds depending on the structure and angles of the knitting machine cams. If the knitting machine cams are even and the same say at 45 degrees on the inward movement and 45 degrees on the outward movement of the knitting hook, the knitting hook will reciprocate in the usual conventional manner. If the knitting machine cams are arranged to start at 45 degrees and that angle is progressively reduced to 30 degrees the needle will reciprocate in the same manner but at a speed that progressively reduces the speed of the needle outward or inward as the case may be. By the same token, the knitting machine cams may be cut to start at 25 degrees and increased to 55 degrees, or any combination which will depend on the movement that is desired with the other needle member as for example an involute or arcuate reciprocating movement by the other needle member which will be of particular use in warp knitting. It will be necessary to activate the other needle member with variable speed knitting machine cams for these movements. If the knitting machine cams are arranged at zero degrees the cams merely form a groove and will not activate the knitting hook or the other needle member. In order to reciprocate the knitting hook horizontally and simultaneously reciprocate the other needle member at degrees vertically, the knitting machine cams are arranged to reciprocate the knitting hook in the usual manner, but the other member is prevented frornreciprocating horizontally by zero degree cams with the result that the diagonal groove in the knitting hook causes the other needle member to reciprocate vertically at 90 degrees. This is the main movement of my two part needle assembly reciprocating bodily and simultaneously at 90 degrees to each other, and this movement is not possible without the diagonal groove.

If the knitting machine cams are arranged to reciprocate both needle members in the same direction, simultaneously, both members will reciprocate horizontally and parallel to each other, and at such time the diagonal groove merely carries the other member back and forth.

If the knitting machine cams are arranged to prevent the knitting hook from reciprocating by zero degree cams, and the other member is reciprocated horizontally the movement of the other member will be a reciprocating diagonal movement as the diagonal groove in the knitting hook will cause the other member to follow the diagonal groove.

If the knitting machine cams are arranged to reciprocate both members in opposite directions, simultaneously, the knitting hook will reciprocate horizontally while the other member simultaneously reciprocates diagonally.

If the knitting machine cams are arranged to reciprocate both members in opposite directions, simultaneously, but at variable speeds depending on the angles of the machine cams, the knitting hook will reciprocate horizontally while the other member simultaneously reciprocates in an involute or arcuate movement which will depend on the construction of the knitting machine cams and the movement desired.

Fig. 5 represents what shall hereinafter be referred to as the other needle member or cast-off member 52 which is the second part of the needle assembly. The part of the cast-01f member up to about the dotted line 22 is about one-half the thickness of the needle in order to fit into the first part or knitting hook of the complete needle. The cast-ofif member is activated by machine cam action on the vertical butt 29 at the edges 23 and'24 and also at the back edge 25. In addition,

the cast-off member is activated by movement of the diagonal groove 19in the knitting hook part of the needle. The position of the vertical butt 29 and the total length of the needle may be varied as required. The angle 21 between the vertical butt 29 and the cast-oil member and the projecting point 7 may also be varied. Modifications and additions may be made to the projecting point 7 as required for the purpose of spreading a loop or loops.

The cast-ofi member is composed of a diagonal shank or butt 60, a vertical butt or shank 29 with an L-shaped point 7, the two parallel diagonal edge surfaces 68 and 69 form a diagonal shank or butt 60, or the diagonal shank or butt 60 forms 2 parallel diagonal cast-01f member cams at 68 and 69. At certain times, the cast-off member will function as a vertical shank 29 with a diagonal butt 60 and at other times it will function as a diagonal shank 60 with a vertical butt 29, depending on which is being activated at the time. The cast-01f member has four different reciprocating movements, horizontal, 90 degree vertical, diagonal and a variable that may be arcuate, involute or other variation depending on the knitting machine cam set up, simultaneously with one reciprocating horizontal movement of the knitting hook member, and an independent diagonal movement where the knitting hook is not reciprocating. Most of the movements of the L-shaped point 7 will be made at the edge or forecut of a dial, cylinder or flat bed needle container, and references are made to this edge or forecut simply to have a point to make movements from, inwardly or outwardly.

In Fig. 6 the tip 30 of the knitting hook may be pointed at various angles to pass through the loop 28 as it is cast-oil? the needle. The tip 31 of the cast-off member also may be pointed at various angles so that the loops 28 may slide over as the loop slides over the shank of the knitting hook. In Figs. 7 and 8, modifications have been made of the cast-off member point for purposes of spreading loops 28. Such modifications or additions are shown at 26 and 27. I

In Figure 9 the knitting hook 32 and the cast-off member 33 are assembled and placed in a dial 34. The forecut 35 is the outside edge of the dial and may be extended to make use of the top 36 for cam action. Since there are no latches to contend with, this extra space can be used for cam action on the needle. The walls of the cylinder or dial at the forecut point may be cut in the conventional manner a suificient distance for proper knitting as shown at 37 in Fig. 10. In Fig. 9 the knitting hook 32 is out and away from the forecut 35 and in position to receive yarn 38 for a new loop. The point of the cast-off member is at the forecut and in position to pick up the old loop 39 from the raised shank of the knitting hook and raise the loop 39 vertically and clear the top of the knitting book.

In Fig. 11 the point of the cast-oit member 33 is in the same position in relation to the forecut 35 but it has been elevated by movement of the knitting hook 32 which has moved inwardly toward the forecut 35. The cast-off member 33 is held in the same position in relation to the forecut 35 by cam action on the butt 23, while the knitting hook moved inwardly toward the forecut 35 by cam action on the butt at 16. This movement of the diagonal groove 19 on the knitting hook 32 raises the cast-off member 33 vertically at 90 degrees, which in turn raises, the old loop 39 into cast-off position. The knitting hook 32 is in position to draw a predetermined length of the loop 38. In the next movement both the knitting hook 32 and the cast-off member 33 will move inwardly simultaneously by cam action on the butts at 16 and 24 and the old loop 39 will be cast-off while the new loop 38 is formed. Fig. 12 represents the simultaneous reciprocating horizontal movement of both needle members where the open arrow represents the horizontal plane and also the reciprocating movement of the knitting hook 32.

The arrow 9 represents the reciprocating horizontal movement of the cast-off memberv 33 where by a reciprocating cam action in the same directions on the

butts

29 and 18 at 15, 16, 23 and 24 a horizontal simultaneous reciprocating movement is provided.

Fig. 13 represents a reciprocating diagonal movement of the cast-off member 33 in relation to the longitudinal plane of the knitting hook 32 whereby a holding cam action on the butt 18 of the knitting hook 32 at 15 and 16 and by a reciprocating cam action on the butt 29 of the cast-oft member 33 at 23 and 24 an independent reciprocating diagonal movement is provided for the castoff member 33 which is also a resultant angle movement represented by arrow 13 and by the arrow 11 where arrow 13 represents the horizontal movement and arrow 11 represents the total vertical movement.

Fig. 14 represents a reciprocating degree vertical movement of the cast-ofi member 33 simultaneously with a reciprocating horizontal movement of the knitting hook 32 where the open arrow 10 represents the horizontal plane of the needle assembly and also the reciprocating horizontal movement of the knitting hook 32. The 90 degree vertical arrow 14 represents the 90' degree vertical reciprocating movement of the cast-off member 33, where, by a holding cam action to prevent horizontal movement on the butt 29 at 23 and 24 of the cast-off member 33, and by a reciprocating cam action on the butt 18 at 15 and 16 of the knitting hook 32, the knitting hook will reciprocate horizontally and the diagonal groove 19 will cause the cast-oi? member 33 to reciprocate simultaneously and vertically at 90 degrees to the horizontal plane of the needle assembly.

Fig. 15 is diagrammatic, showing the main reciprocating movements of the cast-off member in relation to the knitting hook. The open arrow 10 represents the horizontal reciprocating movement of the knitting hook. The

arrows

9, 12 and 14 represent the reciprocating movements of the cast-off member.

In Figs. 16 to 22 inclusive, there is shown a complete knitting cycle in which the dotted line 50 represents the forecut 35 of a cylinder or dial. In Fig. 16 the knitting hook 51 has drawn the length of stitch and formed a loop 39. In Fig. 17 both members of the needle move outwardly and the loop 39 remains in the knitting hook portion 4. In Figs. 18 and 19 the knitting hook 51 continues to move outwardly in relation to the forecut line 50, to receive new yarn 38 and the cast-01f member is held in the same position in relation to the forecut line 50, and is lowered vertically into position to pick up loop 39 which slides to the top of the raised needle shank. In Figs. 20 and 21 the knitting hook moves inwardly toward the forecut line with the new yarn 38, and the cast-off member 52 raises the loop 39 vertically while in the same position in relation to the forecut line 50, and in Fig. 22 both needle members move inwardly to cast-ofi loop 39 and draw the new loop 38. The succeeding movement returns to Fig. 17 in order to complete the knitting cycle. The difference in knitting with other two piece needles is that with my needle assembly the loop 39 in Figs. 19, 20 and 21 is picked up from the shank of the knitting hook 51 and is raised vertically at 90 degrees to clear the incoming hook portion. To the best of my knowledge this is not possible with any other two piece needle assembly, as the loop must slide along an inclined path to reach the proper height for casting off.

In Fig. 23 I have shown a method of knitting a tuck stitch. In the knitting cycle at Fig. 19, in order to knit tuck stitches the next movement is Fig. 23, where both parts of the needle move in simultaneously causing the loop 39 to fall back onto the knitting hook 4 of the knitting'hook 51. In Fig. 24 I have shown another method of knitting tuck stitches. In the knitting cycle at Fig. 21, in order to knit tuck stitches, the next movement is shown in Fig. 24 where the cast-off member 52 remains in the same position in relation to the forecut line 50 and is elevated higher and retains the old loop,

39 while the knitting hook 51 completes its mission of drawing the length of the new loop 38. As the knitting hook 51 moves out the cast-off" member 52 will lower the old loop 39 back onto the shank of the knitting hook 51.

In Fig. 25 I have shown a method of elevating loops and carrying them away from the forecut line 50 in preparation for transfer to another needle. These movements are different from the knitting cycle and at a separate point machine cams are arranged where the knitting hook 51 will not receive yarn for a new loop. The cast-off member 52 will pick up the old loop, as shown in Fig. 20, and elevate it while it carries it the required distance away from the forecut line 50 as shown in Fig. 25, and also as shown at 40 in Fig. 26. The elevation of the loop and the distance carried will depend upon the clearance of one side of the loop and the needle 42 (see Fig. 26) which is to receive the loop, the clearance being on both sides at 47 and 44. The spread of the loop 41 is caused by addition 27 as shown in Fig. 8. The needle 42, which is to receive the loop, is brought up high enough to clear the loop at 44, as shown in Fig. 26. In the next movements, the castoff member will be lowered so that the loop at clearance 44 is well under the knitting hook point at which time the needle 42 will start to move downwardly while the cast-off member moves in toward the forecut line 50 and is lowered to transfer the loop. The side at 44 of the loop 41 will be under the hook of the needle 42 to complete the transfer of the loop.

In Fig. 27 I have shown a variation of the compound needle assembly in which the diagonal groove is on the cast-off member 53 and the knitting hook 54 will now have the movements of the cast-off member shown in Fig. 5. It is a transposition of the activating diagonal groove wherein the movements of the knitting hook are transferred to the cast-off member and vice versa.

In Fig. 28 I have shown a variation where instead of the groove being at an angle, an arcuate groove 55 is made in the knitting hook. By cam action on the butt at edges 45 and 46 the same results as hereinbefore de- 1 scribed for the cast-off member are accomplished.

It is obvious that various changes and modifications may be made in the details of construction and arrangement of parts without departing from the general spirit of the invention.

I claim:

1. A two part knitting needle assembly comprising a knitting hook member having an elongated body portion and a hook-supporting shank extending from one end of the body portion, said body portion having external surfaces adapted to fit for reciprocating sliding movement within and along a needle groove of a knitting machine, and having a straight parallel-walled groove of uniform depth traversing one of said external surfaces, said guide groove being inclined in the direction of reciprocation of said knitting hook member and being generally aligned with the point of said hook, a cast-oft member having a point adapted to cooperate with said hook to cast ofi loops in the knitting operation, said cast-off member having a straight body portion fitting between the walls of said guide groove for sliding movement therein relative to said knitting hook member, the said inclination of the guide groove and the alignment thereof relative to said hook point causing the point of said cast-off member to lie well inwardly of the point of said hook member when remote therefrom, and to move outwardly and over the point of the hook upon relative movement of said castoff member along said guide groove toward said hook point.

2. The structure defined in claim 1, wherein the guide groove has one wall thereof at least approximately aligned with the point of said hook.

3. The structure defined in claim 1, wherein the guide groove that receives the body portion of the sliding castoff member is of a depth substantially equal to the thickness of the body portion. of the cast-off member to present a substantially uniform thickness of said assembly for fitting within said needle groove.

4. The structure defined in claim 2, wherein the guide groove that receives the body portion of the sliding castoff member is of a depth substantially equal to the thickness of the body portion of the cast-off member to present a substantially uniform thickness of said assembly for fitting within said needle groove.

5. The structure defined inclaim 1, wherein the point on the cast-off member projects from the lower outer end portion of the body of said cast-off member.

6. The structure defined in claim 1, wherein said castoff member has loop spreading means.

7. The structure defined in claim 6, wherein said loop spreading means projects outwardly from a side of said cast-off member and is inclined towards the point of said cast-off member.

8. The structure defined in claim 1, wherein the incline of said groove permits the point of said knitting hook to clear the point of said cast-off member when said knitting hook moves inwardly and said cast-off member is caused to move upwardly.

References Cited in the file of this patent UNITED STATES PATENTS 1,333,156 Burson Mar. 9, 1920 1,339,959 La Montague May 11, 1920 1,385,929 Scott July 26, 1921 1,563,233 Scott Nov. 24, 1925 1,673,634 Page June 12, 1928 2,191,378 Getaz Feb. 20, 1940 2,229,929 Morton et al. Jan. 28, 1941 2,300,804 Peel Nov. 3, 1942 2,399,002 Coile Apr. 23, 1946