US2871686A

US2871686A - Warp knitting machinery

Info

Publication number: US2871686A
Application number: US590749A
Authority: US
Inventors: Porter Allan William Henry
Original assignee: F N F MACHINERY Manufacturing Co LT
Current assignee: F N F MACHINERY Manufacturing Co LT; F N F MACHINERY MANUFACTURING Co Ltd
Priority date: 1955-06-21
Filing date: 1956-06-11
Publication date: 1959-02-03
Anticipated expiration: 1976-02-03
Also published as: DE1164016B; GB797215A

Description

A. w. H. PORTER WARP KNITTING MACHINERY Feb. 3, 1959 4 sheets-sheet 1 Filed June 11, 1956 Inventor /4//an W H For hr By 2 fi Mttorney s 3, 1959 A.'w. H. PORTER 2,871,686

WARP KNITTING MACHINERY Filed June 11, 1956 4 Sheets-Sheet 24 7 I nventor /4//an WH- Porzer Feb. 3, 1959 A. w. H. PORTER I 2,871,686

WARP KNITTING MACHINERY Filed June 11, 1956 4 Sheets-Sheet 5 Inventor /4//an A//% For fer Feb. 3, 195 9 A. w. H. PORTER I ,8

WARP KNITTING MACHINERY Filed June 11,-1956 4 Sheets-Sheet 4 U 20 40 60 60 I I I I I Z00 220 240 260 260 300 520 545) 360 I n ventor Allan N H. Porzer -and the threads are being United States Patent 2,871,686 WARP KNITTING MACHINERY Allan William Henry Porter, Burton-on-Trent, England, assignor to F. N. F. Machinery Manufacturing Company Limited, a British company Application June 11, 1956, Serial No. 590,749 Claims priority, application Great Britain June 21, 1955 11 Claims. (Cl. 66-86) In warp knitting machines in which .the warp threads are laid into the hooks of the knitting needles by warp guides or like members which move to-and-fro from the back to the front of the needles and make shogging movements across the backs and fronts of the needles, the relative positions and movement of the warp guides or like members and needles during the time when the threads are laid in the hooks is of great importance. The matter becomes increasingly critical in high speed machines, in machines where shogging movements of different lengths take place in different knitting cycles, and Y in machines employing several rows of warp guide eyes. The threads generally slope across the backs and fronts of the needles as they are laid in the hooks due to the difference in height of the sinkers and guide eyes, and the angle of slope determines the exact height at which the yarn is laid on the needle. When several rows of guide eyes or like members are used, since they cannot all occupy the same position and since the threads must therefore slope at differing angles from the sinkers and cross the hooks at different heights, the problem is even more aggravated. As the speeds of machines increase the time allowed to the threads to take up their correct position is correspondingly decreased so that the danger of mislapping with resultant dropped stitches and faults in the fabric increases.

In high speed machines the lengths of thread between the sinkers and the guide eyes are caused by the movement of the guide eyes to lie in a curve in a direction transversely to the line of the needles. This kinetic effect on the threads due to the high speed of the guides increases the tendency for mislapping to take place still further.

The present invention provides a motion for the guide eyes or like members which enables them to move in step with the needles during the part of the knitting cycle during which the yarns are laid across the fronts of the needles so that during this period there is very little relative movement along the line of the needle shanks between the hooks of the needle and the guide eyes, substantially the whole relative swinging movement of the guide eyes or like member across the row of needles being transverse to the needles, thus giving an increased period during which the threads can be accurately placed in the needles.

According to the present invention, the warp guides or like members are oscillated in a closed path across the row of needles so that they have a component of movement parallel to, and in the same sense as, that of the needles during the time when the needle hooks are open laid across the needles by the shogging movement of the guides. Preferably the closed path around which the guides or like members move, is of elongated substantially elliptical form, the major axis of the ellipse being transverse to the direction of movement of the needles.- Such a motion can be imparted has a separate reciprocating guides 5 Fatented Feb. 3, 1959 to the guide bars which support the guides or like members quite simply by supporting them on arms whichare pivoted part of the way along their lengths to rockers or slides so that each pivot point is constrained to move on a path lying substantially along the line of the arm the guides back and forth across the row of needles twice in each knitting cycle. This double movement of the guide bars during each knitting'cycle is preferable to only a single movement since it makes it simpler to obtain the correct movement, along the line of movement of the needles, of the guide eyes or like members relative to the needles. It also enables both the needles and also the tongues, in the kind of machine in which each needle tongue to open and close the hook of the needle, to function with a movement which is a simple harmonic motion. It is thus possible to use a driving mechanism in which both the needles and tongues as well as the guide bars are each driven by a single eccentric or crank.

An example of a flat warp knitting machine constructed in accordance with the invention is illustrated in the accompanying drawings in which:

Figure 1 is a cross-section through a part of the machine showing the knitting elements and their driving mechanisms;

Figure 2 is a similar cross-section to that shown in Figure 1, but for clarity showing only the mechanism for driving the needles.

Figure 3 is a similar cross-section to that shown in Figure 1 showing only the mechanism for driving the tongues.

Figure 4 is a Figure 1 showing only guide bars.

Figure 5 is a similar cross-section to that shown in Figure 1 showing only the mechanism for driving the sinkers.

Figure 6 is a timing diagram showing the relationship between the movements of the needles, tongues, guide eyes and sinkers, and

Figure 7 is a diagram showing the path of movement of the guide eyes, and also the path of movement of the guide eyes relatively to the tips of the hooks of the needles.

The machine to be described with reference to the accompanying drawings ,is of the kind which has a row of reciprocating needles arranged side by side in a straight line, each of the needles having a tubular shank in which a tongue is situated which moves up and down independently of the needle and so opens and closes the book of the needle during different parts of the knitting cycle.

As shown in Figures 1 and 2, a row of needles 1, are arranged side by side and are clamped to a needle bar 2 by a clamping plate 3. The needle bar 2 is carried at intervals along its length by brackets 3a mounted on rods 4 which can slide up and down in guides 5. The are in turn fixed to a bed 6 of box-shaped. section which extends across the whole width of the machine. The bed 6 forms a frame from which all the knitting elements of the machine .are supported. A driving shaft 7 extends also across the whole width of the machine within a sump 8 mounted below the bed 6 and is carried at intervals along its length in journal bearings 9 which are fixed to the bed 6. Each of the rods 4 is similar cross-section to that shown in the mechanism for driving the connected by a connecting rod 10 to an eccentric 11 on plete revolution for each knitting cycle of the machine and so causes the needles 1 to move upwards and downwards once during each knitting cycle. As shown in Figure 3, tongues 12 are slidable in the tubular shanks of the needles 1 and are attached to a tongue bar 13 which is carried at intervals along its length by brackets 13a, which are similar to the brackets 3a, and are mounted on rods 14, which are similar to the rods 4 carrying the needle bar 2, and slide in guides 14a. tongue bar 13 is moved up and down in an exactly similar manner to the needle bar 2 by eccentrics 15 on the shaft 7 which operate through connecting rods 16. The needles and tongues cooperate with each other in the manner described in the specification of United States Patent No. 2,292,287.

The machine has three

guide bars

17, 18, and 19, each carrying a row of guide eyes. The

guide bars

17, 18 and 19 are supported at intervals along their lengths on arms 20. Each arm 20 is pivoted on .a pin 21 carried by a link 22 which is in turn pivotally connected by a pin 23 to a bracket 24 mounted on the bed 6. The end of each arm 20 away from the

guide bars

17, 18 and 19 is formed as an eccentric strap 25 which embraces an eccentric 26 on a secondary driving shaft 27. The secondary driving shaft 27 is driven from the main driving shaft 7 through

skew gears

28, 29 and 30 and 31 and an intermediate shaft 32 which is carried in a bearing 33 in the bed 6, and in a bearing 34 fixed to a bracket 35 which is also mounted on the bed 6. The skew gear 30 has twice as many teeth as the skew gear 31, and thus the shaft 27 is rotated at twice the speed of the main driving shaft 7. Conventional sinkers 36 having nebs 36a and knock-over-edges 36b are mounted on a sinker bar 37 which is carried at intervals along its length on arms 38. Each arm 38 is pivotally mounted on a link 39 which is in turn pivotally mounted on a bracket 40 which is fixed to the bed 6. The end of each arm 38 remote from the sinker bar 37 is pivotally connected to one arm 41 of a bell crank lever 42. The bell crank lever 42 is rotatably mounted on a shaft 43 which extends along the length of the machine and is carried at intervals by brackets 44 fixed to the bed 6. Another arm 45 of the bell crank lever 42 is pivotally connected to a connecting rod 46 which has a strap 47 surrounding an eccentric 48 on the main driving shaft 7.

In operation the needles 1 are oscillated upwards and downwards by the eccentrics 11 to perform the movement shown by curve A in Figure 6. The eccentrics 11 have an eccentricity of 0.25 inch so that the amplitude of the needle movement is 0.5 inch. The tongues 12 are similarly oscillated by the eccentrics 15 which have an eccentricity of 0.22 inch so that the amplitude of the tongue oscillation is 0.44 inch. The eccentrics 15 are angularly offset from the eccentrics 11 by 75, so that the oscillation of the tongues lags 75 behind that of the needles. The movement of the tongues is shown by curve B of Figure 6. The vertical datum of these two curves is the height of the tip of the needle hook when the needle is in its lowermost position. With the setting shown in these curves the needle hook is closed by the tongue at 284 /2 and is opened again at 326.

The guide bars 17, 18 and 19 and the guide eyes which are attached to the respective guide bars are moved to and fro from right to left and left to right with a substantially horizontal component of movement having an amplitude equal to twice the eccentricity of the eccentric 26, that is, an amplitude of 0.55 inch. At the same time the right hand end of the arm 20 as seen in Figure 4, is moved upwards and downwards by the eccentric 26. This upwards and downwards movement is transmitted to the

guide bars

17, 18 and 19 in the ratio of the lengths of the two parts of the .arm 20 on each side of the pivot pin 21. The upwards and downwards movement of the

guide bars

17, 18 and 19 is thus smaller than the movement from right to left and left to right, and the guide eyes thus move along the path shown by curve X in Figure 7. This path is substantially elliptical in shape the major axis being appropriately seven times greater than the minor axis. The projection of the movement of the guide eyes transversely to the row of needles is shown by curve C of Figure 6. The angular position of the eccentric 26 is adjusted so that the guide eyes are at the end of their movement at the back of the needles, that is to the left as shown in Figures 1 and 4 just after the needles have reached their position as shown by curve A. Since the frequency of the guides is twice that of the needles, the guides swing to their fullest extent to the front of the needles just after the needles have reached 180 in their own cycle which is the knitting cycle of the machine. This is at the point e on curve C 'in Figure 6, and corresponds to the point 2 shown on curve X in Figure 7. Point d on curve C in Figure 6 corresponds similarly to the point d on curve X of Figure 7 and it can thus be seen that during the portion of the cycle from d to e the guide eyes have an upward component of movement in the same sense as the movement of the needles which during the same period have a movement represented by a portion of curve A between the points 3 and g.

During the following 90 of the cycle of movement of the guide eyes, that is from e to d as shown on Figure 7, it will be seen that the path of the guide eyes remains substantially level and thus has an upward movement relative to the needle hooks. The tendency for the loops of thread, whilst they are being formed round the shanks of the needles, to slide down the shanks away from the hooks is thus reduced.

Curve D in Figure 6 shows the longitudinal movement of the guide bars and guide eyes during each knitting cycle. Lapping of the threads takes place as the guide eyes move each across the front of one needle during the movement represented by a portion of curve D from h to j.

The eccentric 48 moves the connecting rod 46 upwards and downwards and so causes the bell-crank lever 42 to oscillate about the shaft 43. This oscillation is transmitted to the sinkers 36 which move to and fro from right to left along an arc centred at the centre of the pin connecting the link 39 to the bracket 40. The angular position of the eccentric 48 is adjusted so that the sinkers move according to curve E in Figure 6. The nebs 36a are fully engaged between the needles at 320 and fully withdrawn at in each knitting cycle.

During the second 180 of the machine cycle, the guide eyes repeat their oscillation around the substantially elliptical path but during this time the needles 1 are near the bottom of their stroke and are closed by the tongues 12 as shown by curves A and B. The needles are withdrawn between the sinkers 36 and are unaffected by the second oscillation of the guide eyes which is idle to the extent that no loop forming or laying of threads into the needle hooks occurs. The second oscillation of the guide eyes, however, enables the threads to be positively registered with the sinker nebs 36a as rapidly and as long as possible after the nebs have been withdrawn from between the needles to allow knock-over to occur. The sinkers may be driven by the usual arrangement of double eccentrics operating in parallel but the arrangement described using single eccentrics is made possible, with consequent simplification of the machine, because a less favourable sinker movement is made acceptable.

Curve Y of Figure 7 shows the movement of the guide eyes relative to the needle. The period of the cycle from h to j corresponds to the portion of curve D of Figure 6 between I: and j, when the guides are moving across the fronts of the needles to lay the threads into the hooks. The guides are coincident with the fronts of the needles, as they cross at the point k on curve Y and thus it will be seen, since the portion of curve Y between h and k is substantially horizontal that there is very little relative vertical movement between the needles and the guide eyes, whilst the threads are actually laid into the hooks of the needles.

Instead of supporting the arm 20 which carries the guide bars 17, 18 and 19 on the pivoted link 22, the pivot pin 21 may be carried in a guide which constrains it to move in a straight line parallel to the axis of the straight portion of the arm 20. By this means the guide eyes are moved along a path which is a true ellipse.

The length of the minor axis of the substantially elliptical path of the guide eyes is relatedto the length of the needle stroke and the length of the major axis is related to the number of rows of guide eyes with which the machine is provided, the greater the number of rows, the longer the major axis of the ellipse must be.

The invention enables the warp threads from multiple rows of guide eyes or like members arranged to lie in sequence on the path of the needle hooks relative to the guides to run into the hooks, during lapping, in succession so that they do not 'nterfere with each other.

I claim:

l. A flat warp knitting machine including a row of hooked needles, means for reciprocating said needles, means for opening and closing the hooks of said needles, warp thread guide means for laying warp threads in the hooks of said needles when said hooks are open and means for oscillating said guide means in a closed path having a principal component transverse to the direction of movement of said needles, said oscillating means moving said guide means with a component of movement parallel to, and in the same sense, as the movement of said needles during the time when the needle hooks are open and the threads are being laid across said needles.

2. A flat warp knitting machine including a row of hooked needles, means for reciprocating said needles, means for opening and closing the hooks of said needles, warp thread guide means for laying warp threads in the hooks of said needles when said hooks are open and means for oscillating said guide means in a path of elongated substantially elliptical form, the major axis of said ellipse being transverse to the direction of movement of said needles. 1

3. A fiat warp knitting machine including a row of hooked needles, means for reciprocating said needles, means for opening and closing. the hooks of said needles, warp thread guide means for laying warp threads in the hooks of said needles when said hooks are open and means for oscillating said guide means in a closed path, said oscillating means moving said guide means with a component of movement parallel to, and in the same sense, as the movement of said needles during the time when the needle hooks are open and the threads are being laid across said needles the frequency of oscillation of said guide means being twice the frequency of reciprocation of said needles.

4. A flat warp knitting machine including a row of hooked needles, means for reciprocating said needles, means for opening and closing the hooks of said needles, warp thread guide means for laying Warp threads in the hooks of said needles when said hooks are open and means for oscillating said guide means in a path of elongated substantially elliptical form, the major axis of said ellipse being transverse to the direction of movement of said needles, said oscillating means moving said guide means twice round said substantially elliptical path during each cycle of reciprocating movement of said needles.

5. In a fiat warp knitting machine, a reciprocable needle bar, a row of hooked needles fixed to said needle bar, means for reciprocating said needle bar, an arm, a guide bar connected to said arm, warp guide members carried by said guide bar, means for moving one end of said arm along a circular path, means pivoting said arm at a point spaced away from said one end of said arm and means constraining said pivot means to move along a (I said path lying substantially along' the line of said arm, whereby said guide members are moved along a path of elongated substantially elliptical form, the major axis of said ellipse being transverse to the direction of movement of said needles.

6. -A flat warp'knitting machine as claimed in claim 5, wherein said constraining means includes a fixed member and a link pivotally connected to said fixed member, said arm being pivoted to said link.

7. In a flat warp knitting machine, a reciprocable needle bar, a row of hooked needles fixed to said needle bar, means for opening and closing the hooks of said needles, a first eccentric operatively connected to reciprocate said needle bar, an arm, a guide bar carried by said arm, warp guide members carried by said guide bar, for laying warp threads in the hooks of said needles when said hooks are open, a second eccentric operatively connected to move said one end of said arm along a circular path, means pivoting said arm at a point spaced away from said one end, means constraining said pivot means to move along a path lying substantially parallel to said arm, means for rotating said first eccentric and means for rotating said second eccentric, whereby said guide members are moved along a path of elongated substantially elliptical form, the major axis of said ellipse being transverse to the direction of movement of said needles and the relative angular positions of said first and said second eccentrics being arranged so that said guide members have a component of movement parallel to and in the same sense as the movement of said needles during the time when the needle hooks are open and the threads are being laid across said needles.

8. A fiat warp knitting machine as claimed in claim 7, wherein the speed of rotation of said second eccentric is twice the speed of rotation of said first eccentric.

9. A flat warp knitting machine including a row of reciprocable hooked needles, a row of reciprocable tongues cooperating one with each of said needles, a first eccentric operatively connected to impart a simple harmonic motion to said needles, a second eccentric operatively connected to impart a simple harmonic motion to said tongues to open and close the hooks of said needles, means for rotating said first and second eccentrics, warp thread guide means for laying warp threads in the hooks of said needles when said hooks are open and means for oscillating said guide means in a closed path, said oscillating means moving said guide means with a component of movement parallel to and in the same sense as the movement of said needles during the time when the needle hooks are open and said warp threads are being laid across said needles.

10. A fiat warp knitting machine as claimed in claim 9, further comprising sinkers lying between said needles, nebs on said sinkers movable to and fro into and through the plane of action of said needles, a third eccentric operatively connected to impart a harmonic motion to said sinkers and nebs, and means to rotate said third eccentric.

11. A flat warp knitting machine including a row of reciprocable hooked needles, a row of reciprocable tongues co-operating one with each of said needles, a first eccentric operatively connected to impart a simple harmonic motion to said needles, a second eccentric operatively connected to impart a simple harmonic motion to said tongues to open and close the hooks of said needles, means for rotating said first and second eccentrics, an arm, a guide bar carried by said arm, warp guide members carried by said guide bar for laying warp threads in the hooks of said needles when said hooks are open, a third eccentric operatively connected to move said one end of said arm along a circular path, means pivoting said arm at a point spaced away from said one end, means constraining said pivot means to move along a path lying substantially parallel to said arm and means for rotating third eccentric whereby said guide members are moved along a path of substantially elliptical form, the major axis of said ellipse being transverse to the direction of movement of ,said needles and the relative angular positions of said first and said third eccentrics being arranged so that said guide members have a component of movement parallel to and in the same sense as the movement of said needles during the time when said needles hooks are open and said warp threads are being laid across said needles.

References Cited in the file of this patent UNITED STATES PATENTS Peters June 21, 1955 FOREIGN PATENTS Great Britain June 7, 1882 Great Britain of 1884