US3132406A - Needle loom - Google Patents

Description

y 2, 1964 A. M. SMITH n 3,132,406

NEEDLE LOOM Filed March 16, 1962 8 Sheets-Sheet 1 INVENTOR. fizz/440:2 flf 5311/2745 I Mi fimMW A. M. SMITH H May 12, 1964 NEEDLE LOOM Filed March 16, 1962 8 Sheet -Sheet 2 IIVVENTOR.

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May 12, 1964 A. M. SMITH 1| NEEDLE LOOM Filed March 16, 1962 8 Sheets-Sheet 3 I I I I I I I I I M y 1964 A. M. SMITH :1 3,132,406

NEEDLE LOOM Filed March 16, 1962 8 Sheets-Sheet 4 0 INVENTOR.

BY jmd/fiag/Mm A. M. SMITH ll May 12, 1964 NEEDLE LOOM 8 Sheets-Sheet 5 Filed March 16, 1962 a 2 M W W M M an y 1964. A. M. SMITH 11 3,132,406

NEEDLE LOOM Filed March 16, 1962 8 Sheets-Sheet 6 I Ma May 12, 1964' A. M. SMITH n NEEDLE LOOM 8 SheetsSheet '7 Filed March 16, 1962 m ATTORNEYS y 12, 1964 A. M. SMITH u 3,132,406

' NEEDLE LOOM Filed March 16. 1962 8 Sheets-Sheet 8 mmvroza. film mace 52W; 47

United States Patent 3,132,406 NEEDLE LOOM Alexander M. Smith 1!, Elkin, N.C., assignor, by mesne assignments, to Fiberwoven Corporation, Eilrin, N.C., a corporation of North Carolina Filed Mar. 16, 1962, Ser. No. 180,158 45 Claims. (c1. 28-4) The present invention relates to a needle loom and, more particularly, to an improved needle loom for needling a web or batt of loosely matted fibers into a needled fabric. While the improved needle loom of the present invention is particularly adapted to produce a I needle fabric having a chain entanglement of fibers including subsurface interlooping and/or interlacing of fibers capable of use for blankets, wearing apparel, draperies or the like, it also may be used to punch webs in the preparation of the web for use in making papermakers felt, upholstery fabrics, filters or the like.

The needle loom of the present invention is a specific improvement over the apparatus disclosed in my copending United States patent applications serially numbered 29,115, filed May 13," 1960, now United States Patent No. 3,090,099; and 31,910, filed May 26, 1960, now United States Patent No. 3,090,100, and is capable of producing needled products disclosed therein by the methods disclosed therein.

Needled fabrics, which are sometimes referred to as non-woven fabrics, derive their coherence and strength from interfiber entanglement and accompanying frictional forces. Heretofore, needled fabric structures have been produced in needle looms by subjecting a web or batt of loosely matted fibers to a number of punchings on one side by an array of needles so as to reorient the fibers and compress the web, the web then being subjected to a number of punchings on'the other side to further reorient fibers and compress the web. In some instances, the needle looms have been provided with needles on opposite sides of the web. In these instances, the needle boards have been displaced from each other in the longitudinal direction of the web and have simultaneously punched the web from both sides. In my above-mentioned copending applications, a new and improved needled fabric structure having increased strength and uniform appearance on both sidesis produced by a novel needle loom wherein the web is alternately punched from one side and then the other side by opposed needle boards each having an array of needles, the needles of one needle board traveling in mirror image paths of the needles of the other needle board. By such an arrangement, the control of the fiber orientation is ,positive throughout the web and chain entanglement of fibers is developed in contiguous rows extending'lengthwise of the web, the fibers also interlocking between rows by interlooping and/or interlacing.

While the improvements in needle looms of the present invention are primarily intended to produce a needled fabric such as disclosed in my aforementioned copending applications, certain improvements are also capable of being employed in any needle looms having oscillating needle boards.

An object of the present invention is to provide an improved needle loom having an oscillating needle board capable of high speed oscillations to and fro whereby a needled fabric may be produced at a high rate. In large needle looms, the needle boards often have a length of 110 inches and over and in some instances over 200 inches. The needle board which has its length extending across the width of the web is quite heavy and a large force is required to reverse its motion twice in each cycle. This force increases as the rate of oscillation increases and causes the drive crank hearings to be heavily loaded.

3,132,406 Patented May 12 1964 CCv ing stresses due to its length and to the high acceleration force which occurs when its motion is reversed. In'addition, the oscillation of a needle board at high speed transmits large periodic forces to the frame of a needle loom which must be carefully balanced if the machine is to have stability. Consequently, heretofore it was necessary to operate needle looms at relatively slow speeds in order to eliminate excessive flexure of the needle board, to provide practical crank bearing loads and to reduce the problems resulting from imbalance.

Ancillary to the preceding object, it is a further object of the presentinvention to provide a needle loom in which the masses, motions and dimensions ef the moving parts are equal and arranged in a'mirror imageof each other, such that the forces created by oscillation of the needle boards and applied to the frame structure of the 100111 are equal and opposite and are thereby balanced, thus permitting faster oscillation of the needle boards so that more production is accomplished than heretofore realized.

Another'object of the present invention is to provide an improved needle loom wherein a driving force is applied at uniform small intervals across the length of the needle board and thereby the fiexure of the needle board due to forces caused by acceleration and deceleration is reduced.

Still another object of the present invention is to provide an improved needle loom in which moving parts and a spring means comprise a resonant system such that very small loads are placed on crank armsv and bearings of said loom after oscillation has been started, such crank arms also serving to give a definite limit to the amplitude ofthe needle board oscillation.

Still another object of thepresent invention is to providean improved needle loom comprising at least one needle board oscillating at high speed to and fro between predetermined points, the needle loom including means whereby a primary springdriving force can be uniformly applied across the needle board to counteract acceleration forces, the primary driving'force being activated viding a needle loom which has an auxiliary power means to initiate a resonant spring system and another power means for operation once the moving parts are oscillating.

A still further object of the present invention is to provide a needle loom having a needle board oscillating to and fro between predetermined points, the needle loom being provided with means for storing up potential energy at spaced small intervals across [the needle board during its movement in both directions and releasing this energy at spaced small intervals across the needle board at the ends of its stroke to reverse its direction.

An additional object of the presentinvention is to provide a needle loom structure having needles mounted in a needle board which oscillate with an angular motion so that the axes of the needles move in paths substantially tangent to circles drawn about the center of rotation and penetrate a fiber web and said structure having stiff and therefore heavy members arranged near axis of rotation where acceleration forces are relatively small and light members located away from the axis of rotation where motion is greater and acceleration forces are relatively large.

One object of the present invention is to provide a needle loom having needles in a pair of opposed needle boards which oscillate in linear motion, the needles of each board of the pair capable of alternately penetrating the web passes therebetween.

Another object of the present invention is to provide a needle loom having a minimum number of bearings per needle board which bearings require maintenance and become a source of product contamination.

Another object of the present invention is to provide an improved needle loom having a plurality of opposed pairs of needle boards, the needles of each board of a pair capable of alternately penetrating the web as the web passes therebetween.

These and other objects and advantages of the present invention will appear more fully in the following detailed specification, claims and drawings in which:

FIGURE 1 is a perspective view illustrating a needle loom of the present invention;

FIGURE 2 is a vertical end view partly in section and partly diagrammatic of the needle loom of FIGURE 1, the view taken from the right side looking toward the left of FIGURE 1 and the top portion being omitted and with the side cover plates also being omitted for purposes of clarity;

FIGURE 2a is a continuation of FIGURE 2 illustrating the top portion of the needle loom;

FIGURE 3 is a plan view partly broken away of the beam or rocker arm structure for one of the needle boards of the needle loom of FIGURE 1, the view being 180 out of phase with a view taken substantially on the line 3-3 of FIGURE 2;

FIGURE 4 is a vertical end view partly in section and partly diagrammatic and illustrating a modified form of needle loom of the present invention;

FIGURE 5 is an enlarged fi'agmentary view illustrating the typical spring means connection to the spar of the rocker arm structure of FIGURE 4;

FIGURE 6 is a sectional view taken substantially on the line 7-7 of FIGURE 5;

FIGURE 7 is an enlarged fragmentary sectional view of the connection for the air spring means of FIGURE 5;

FIGURE 8 is a fragmentary plan view of the rocker arm structure of the loom of FIGURE 4, the view illustrating the positioning of the air spring means on the spars;

FIGURE 9 illustrates diagrammatically a modified spring means arrangement for use with the needle looms of FIGURES 1 or 4 the modification including a leaf FIGURE 10 is an enlarged fragmentary view taken on the line 10-10 of FIGURE 9;

FIGURE 11 is a view diagrammatically illustrating another modifi cation of the spring means, the view showing the use of pairs of coil springs arranged axially of one another;

FIGURE 12 is a view illustrating diagrammatically another modification of the spring means utilizing coil springs on each side of a pivotal axis of the rocker arm structure;

FIGURE 13 is a view illustrating diagrammatically a further modification of spring means and more particularly the use of air springs positioned on each side of the pivotal axis of the rocker arm structure;

FIGURE 14 is a view illustrating diagrammatically another modification of the spring means and specifically the use of air springs mounted one above another and both positioned on the same side of the rocker arm structure;

FIGURE 15 is a view similar to FIGURE 14 but illustrating diagrammatically a still further modification wherein air springs are used on opposite sides of a rocker arm structure;

FIGURE 16 illustrates a still further modification of spring means capable of use with the present invention;

' through FIGURE 17 is a fragmentary view diagrammatically illustrating application of the invention to a needle loom having at least one needle board oscillating in a linear motion path between two points; and

FIGURE 18 is a schematic view of the air system for the air springs of the needle loom of FIGURE 1.

Referring now to the drawings wherein like character and reference numerals represent like and similar parts and in particular to FIGURE 1, the needle loom of the present invention is illustrated in perspective. It will be understood that the needle loom of the present invention receives a web or batt of loosely matted fibers from any suitable source of supply, the web being fed to the needle loom by suitable conveyor structure. Usually the loosely formed web comprises a plurality of layers of fibers formed by a carding machine and fed therefrom to the conveyor which transfers the web to the needle loom. A web formed by depositing fibers from an air stream may be used alone or in conjunction with a conventional lapper. Several means of web forming may be combined; thus, the fibers of the layers making up the web or batt may be oriented variously with respect to the length of the web or batt as the same passes through the needle loom.

The needle loom of the present invention has a frame structure generally designated at 10 which includes a framework of vertical and horizontal members made from channel sections, I-beams, box beams or the like and forming a box-like structure. In more detail, the frame structure 10 is provided with two end sides 12 and 14 each made up of upper and lower horizontally extending channel shaped member 16 and 18 extending between and rigidly secured to a vertical channel 19 and to a vertical box-shaped standard 20. Upper and lower cross beams 22 and 24, respectively, extend between the end sides 12 and 14 so as to form the substantially rigid box-like frame structure. Any suitable side cover plates 26, 28 and 30 may be utilized to enclose the end sides of the frame structure.

The box-like frame structure is suitably supported on a plurality of pedestals 32. Preferably the pedestals 32 are individually adjustable with respect to one another in order that the needle loom may be suitably leveled on the mill floor.

As best shown in FIGURES 1 and 2, the needle loom of the present invention is provided with a lower pair of opposed needle boards generally designated at 34 and an upper pair of opposed needle boards generally designated at 36. It will suffice to say at this time the pairs of needle boards 34 and 36, respectively, oscillate in an angular or curved path between predetermined points, it being understood that each pair of needle boards 34 and 36 are moved simultaneously so that the needles of the boards of each pair alternately penetrate the web on both sides. Also, it will suflice to say at this point in the specification that the pairs of needle boards 34 and 36, respectively, move in opposite directions so that the needles of the lower needle board of the pair 36 is penetrating the web at one place thereon while the needles of the upper needle board of the pair 34 is penetrating the web at a different place thereon. A more detailed description of the movement of the pairs of needle boards 34 and 36 will appear later in the specification.

The web of loosely matted fibers is diagrammatically shown in FIGURE 2 by the broken line designated by the numeral 38. It enters the lower portion of the needle m and passes between the lower pair of needle boards 34 and outwardly therefrom and upwardly around suitable guide rollers 40, 42 and 44 and then back horizontally through the center unobstructed portion of the needle loom. Web. 38 is then guided upwardly around rollers 46, 48, and then horizontally between the upper pair of needle boards 36. As described in my aforementioned application Serial No. 31,910, the feed of the web 38 the needle loom is in step-by-step increments with the needles of the needle boards penetrating the web while the web is in a dwell or stationary. It is also within the scope of the present invention that the step-by-step movement of the web 38 may be such as disclosed in my aforementioned application Serial No. 29,115 wherein the web is moving as the needles of the needle board begin penetration and then is stationary as the penetration is continued. The rollers may be positively driven in stepby-step increments by a suitable oscillating rod 49 extend ing to a suitable one-way clutch and brake assembly 51.

The lower pair of opposed needle boards 34 includes an upwardly facing needle board 50 having many of needles 52 extending therefrom and an upper downwardly facing needle board 54 having an array of needles 56 extending downwardly therefrom. The needle boards 50 and 54 are carried on one end of rocker arm structures 58 and 60, respectively. The rocker arm structures 58 and 60 are each pivotally mounted in the frame structure it on vertically spaced horizontally extending axes indicated at 62 and 64, respectively, the axes 62 and 64 of the rocker arm structures 58 and 60 being intermediate the ends of the same. The upper pair of opposed needle boards 36 include a lower upwardly facing needle board 66 having an array of needles 68 and an upper downwardly facing needle board 70 having an array of needles 72. Rocker arm structures 74 and 76 support the needle boards 66 and 70, respectively, for pivotal movement about vertically spaced horizontal axes 78 and 80, respectively. From FIGURE 2, it will be apparent that all of the pivotal axes 62, 64, 78 and 80 of the rocker arm structure lie in a common vertical plane extending widthwise of the frame structure 10, the mounting of the lower pair of needle boards being a mirror image of the mounting of the upper pair of needle boards 36.

Preferably the array of needles 52 and the array of needles 56 of needle boards 50 and 54 travel in mirror image paths of one another as they alternately penetrate the web 38. The path of penetration of the needles 52 and 56 extends at an angle and opposite the direction of advancement of the web 38 between the needle boards 50 and 54. The preferable angle for the needles 52 or 56 is a tangent of an are having a center of curvature common with the pivotal axes 62 or 64 of rocker arm structures 58 and 60, respectively, the are having a radius equal to the distance between the desired point of penetration of the needle and the respective pivotal axes 62 or 64.

Each array of needles 68 and 72 of the upper needle boards 66 and 70 also have mirror image paths of penetraion through the web 38. The needles 68 and 70 are arranged in the needle boards 66 and 7'3 so as to extend in a directionopposite to the direction of feed of the web between the needle boards. Their angles are determined in a similar manner to the angles of the needles of the lower pair of needle boards.

Web guide plates 82 and 84 provide a path for the web 38 to travel as the same passes between the pair of needle boards 34. The guide plates 82 and 84 are provided with curved inlet portions defining an enlarged throat and a plurality of holes (not shown) arranged so that an array of needles of the needle boards can pass therethrough.

Guide plates 82 and 84 may be secured to the frame structure in any suitable manner. Guide plates 86 and 88 carried by the frame structure 10 between the upperpair of needle boards 36 are substantially similar to the gmide plates 82 and 84 with the exception that the infeed throat portion is not quiteas large. It will be appreciated that the fabric structure of the web has already been needled on both sides and compressed considerably prior to entering between the guide plates 86 and 88 so there is no necessity of providing a wide inlet throat.

The rocker arm structure 76 is best illustrated in plan view on FIGURE 3. It will be appreciated that the other rocker arm structures 58, 60 and 74 are substantially identical to the rocker arm structure 76 and therefore the description of one rocker arm structure will suffice. The rocker arm structure includes an elongated axle memher 90 having its end portions 92 carried in suitable bearings 94 supported on the end sides '12 and 14. The axle member 9t? has rigidly secured thereto at spaced points along its longitudinal axis a plurality of spar members 96. A tubular member 98 (FIGURE 2) is rigidly secured to the ends of each of the spar members 96 whereas a beam member 100 extends through each of the spar members 96 and is secured thereto forward of and in spaced relationship to the axle member 90. The needle board 70 which includes the body member 102 is rigidly supported on the ends of the spar members opposite the ends supporting thetubular member 98 by a clamp ar rangement including the clamps 104 and 106.

The elongated needle board 70, as shown in FIGURE 3, as well as the other three needle boards, has a length which extends completely across the width of the web 38 upon which it is operating. As mentioned at the outset of the specification, such needle boards oftentimes have lengths in excess of inches and, in some instances, as great as 200 inches or more. Since the needle boards are supported on the end of the rocker arm structures, they have an angular path of motion as determined by their distance from their pivotal axes. Furthermore, as the needle boards are oscillated and, thus, decelerated and accelerated at the end of each stroke, tremendous forces are created which must be resisted by the frame structure 10 through the axle member 90 and by the driving means.

In needle looms heretofore designed, the oscillation speed of the needle boards was limited because the reciprocating forces in such needle looms were not effectively balanced. In other words,if the speed of oscillation was increased to a certain point, the forces caused by the reciprocation of the needle board became so great as to cause dangerous vibrations in the frame structure and, consequently, the output of the needle loom was limited to slow movement of the needle board or boards. By the arrangement of identical pairs of needle boards 34 and 36, as shown in FIGURE 2, oscillating in opposite directions in mirror image motion with one another, the

forces created by the oscillation of the needle boards are.

equal and opposite and thus cancel themselves out in the frame structure so that vibration is reduced to a minimum. The use of a weighted flywheel or crank counterweight as inneedle looms of conventional design cannot give the degree of balance achieved in the mirror image design of the present invention because the accelerations of the masses cannot be made equal and opposite at all times. To obtain the balanced-needle loom of the present invention, the lower pair'of needle boards 34- and upper pair of needle boards 36 are guided in opposite directions of oscillation by connecting rods .108-and 110, respectively, the connecting rods 108 and 1410 being of equal length and operating off of a crank shaft 112 having eccentrics 114 and 116 arranged 180 out-of-phase with each other. The connecting rods 108 and 110 are respectively connected to theeccentrics 114 and 116. A link 1018 pivotally connected to the rocker arm structures 58 anddt) on the ends of their respective drive spars 145 (FIGURE 3 illustrates a similar drive spar 145 for rocker arm structure '76) at 120 and 122, respectively,;is also pivotally connected to theouter end o f the connecting rod 108 at a midpoint 124. Likewise, the upper rocker arm structures 74 and 76 are pivotally connected together by a link .126 which in turn is pivotally connected at 128 to the outer end of connecting rod 110. Upon rotation of the crank shaft 112, the connecting rods 108 and 110 move in opposite directions at all times and, consequently, cause the lower pair of needle boards 34 and upper pair of needle boards 36 to move in opposite directions whereby the forces of the respective pairs of needle boards and rocker arm structures are effectively cancelled out. While FIGURE 2 shows the drive for the pairs34 and-36 of needle boards operatively connected to the drive spars of the respective rocker arm structure on one side of the loom, it will be appreciated that the drive is duplicated on the other side of the loom.

Crank shaft 112, which is mounted in suitable bearing blocks 129 carried on opposite sides of the needle loom, is driven by a motor 130 through suitable fiuid coupling 136 and belting 132 and 140. However, an auxiliary starting motor 134 carried on the top of the frame structure 10, as shown in FIGURE 1, is utilized to assist in starting the oscillation of the pairs of needle boards to overcome the initial compression of the spring drive means to be described in detail later. A suitable clutch arrangement is provided to disengage the auxiliary motor 134 once the pairs of needle boards 34 and 36 and their respective rocker arm structures are oscillating.

While the arrangement of the needle boards of the needle loom thus far described wherein the pairs of needle boards are mounted in the frame structure in mirror image relationship to each other and have a drive in mirror image relationship to each other wherein forces created by their movement are equal and opposite at all times thus permitting increased speed of oscillation of the needle boards in an angular pattern, it will be appreciated that the same mirror image principle of cancelling acceleration forces can be employed with needle boards moving in linear motion. Also, it will be appreciated that such an arrangement further increases production of the needled fabrics in that the utilization of a plurality of pairs of opposed needle boards increases the number of punches per square inch of area of needled fabric being discharged from the loom. In other Words, the needle loom of the present invention does not require a plurality of passes of the web through the machine to obtain sufficient fiber entanglement. In this respect, the product produced by the needle loom of the subject invention has a softer hand even before napping, increased strength, and a uniform appearance on both sides after napping as the fiber entanglement by the alternately penetrating needle boards of the pair is the same throughout the finished web.

The needle boards of the present invention may be made according to the disclosure in my copending application Serial No. 142,949, filed October 4, 1961, and entitled Needle Board for Needle Loom and Method of Making Same. While the aforementioned application discloses an improved needle board and method of making the same, the needle board being lighter in weight than those needle boards heretofore used in needle looms, it will be appreciated that such needle boards, because of the great number of needles carried thereby and because of their elongated length, still have a considerable mass.

An oscillating needle board decelerates and accelerates at the ends of each stroke; the maximum acceleration being directly proportional to the stroke length and to the second power of the speed of oscillation. In the desired range of operation this acceleration reaches a magnitude equivalent to 35-60 times the acceleration of gravity. The needle board being thus accelerated is subjected to a very great driving or resisting force which in needle looms heretofore has usually been applied near the ends of the needle board by crank arms. In the past, the magnitude of this acceleration with the resulting heavy load on the crank arm bearings and the tendency of the needle board itself to bend or flex between the drive points resulted in uneven needle penetration.

Referring now to FIGURES 2, 3 and 18, it will be noted that the needle loom of the present invention is provided with spring means positioned between the frame structure and each of the oscillating rocker arm structures and needle boards, the spring means being capable of storing potential energy as the needle boards move toward one end of their stroke, the spring means releasing kinetic energy operatively uniformly across the needle board to assist the cranks in driving the needle boards in an opposite direction. By utilizing the spring means arrangement of the present inventioncoupled with the crank means for oscillating the needle boards, it will now be evident that the load on the crank bearings can be made very small and that a driving force is applied at uniform small intervals across the entire length of the board thereby eliminating fiexure in the needle board.

In more detail, the frame structure 10 is provided with a plurality of cross beams 142 rigidly secured to and extending between the sides 12 and 14 of frame structure 10, the cross-beams 142 being arranged with respect to the rocker arm structures, as shown in FIG- URE 2. In the environment disclosed, there are two cross-beams 142 associated with each rocker arm structure, the cross-beams extending parallel to the pivotal axis of the rocker arm structure and spaced on each side of such pivotal axis. Each pair of cross-beams 142 is arranged on an opposite side of a rocker arm structure from its needle board so as not to interfere with the oscillation of the rocker arm structure or the feed of the web 38 through the needle loom. As shown in FIGURES 2 and 3, the two cross-beams 142 cooperating with the rocker arm structure 76 are arranged above and in spaced parallel relationship to the tubular member 98 and beam 100 of the rocker arm structure.

A plurality of air springs 144 are positioned between the cross-beam 142 and the tubular member 98. Each of the air springs 144 include a plate member 146 rigidly connected to the cross-beam 142, a second plate member 143 rigidly connected to the tubular member 98 and a flexible wall 150 therebetween. Similar air springs 152 are positioned between the cross-beam 142 and the beam 100 of the rocker arm structure 76. When the rocker arm structure 76 is oscillated in a clockwise direction about its pivotal axis 80, as viewed in FIGURE 2, the beam 100 of the rocker arm structure moves toward the cross-beam 142 causing compression of the air in the air spring 152 and the build up of potential energy therein. Since there are a plurality of air springs 152 arranged across the rocker arm structure 76, the build up of potential energy is uniformly distributed across the rocker arm structure. The tubular member 98 moves away from its cooperating cross-beam 142, and, consequently, there is a decrease in air pressure within the air springs 144 after they have expended their kinetic energy. At the end of the stroke, the connecting rod passes through dead center and then starts to return the rocker arm structure 76 in a counterclockwise direction. The potential energy stored up in the springs 152 across the rocker arm structure 76 between the same and the frame structure is then uniformly released as kinetic energy and thus a driving force is effectively applied to the needle board across the length of the same through the rocker arm structure. Conversely, as the rocker arm structure 76 moves in a counterclockwise direction, as viewed in FIGURE 2, potential energy is stored up in the air springs between the frame structure and the rocker arm structure through its tubular member 98, this potential energy being released as kinetic energy at the end of the stroke in the counterclockwise direction.

It will be noted that the cooperating rocker arm structure 74 is provided with a plurality of air springs 154 and 156 which cooperate with its tubular member 98 and beam 100, respectively. The air springs 154 and 156 operate identically with the air springs 144 and 152 except they are out-of-phase In other words, when the rocker arm structure 74 is moving in a clockwise direction along with the rocker arm structure 76, its air spring 154 between the cross-beam 142 and tubular member 98 is compressed whereas its air spring 156 is expanded.

The lower pair of rocker arms 58 and 60 are similarly provided with air springs 158, 160, 162 and 164. The action of the air springs 158, 160, 162, 164 of the lower pair of rocker arm structures 58 and 60 is identical with the action of the air springs 144, 152, 154 and 156 of the upper pair of rocker arm structures. Consequently, by having the air springs arranged in this manner, there is also a balancing of the forces created by the conversion of potential energy into kinetic energy in the respective rocker arms at each end of their strokes.

Each of the air springs mentioned above is capable of having the mean air pressure therein varied and thus the eifective spring constant of the air springs can be varied. This is particularly important in that it is highly desirable that the air springs have a loW spring constant; that is, be as ineffective as possible when the needle loom is started. By eliminating or reducing the air pressure within the air springs prior to starting of the needle loom, the load on the starting motor is materially reduced. Once the needle loom has been started, then air under pressure is applied to the air springs in order to provide them with spring constant suitable for the desired speed of operation. Also, the invention contemplates providing individual adjustment of the air springs while the needle loom is operating in order to obtain a desired distribution of kinetic energy to the various needle boards.

Referring to FIGURE 18 which schematically illusstrates air springs 144, 152, 154 and 156, it will be noted that those air springs ofv a pair of rocker arm structures which compress on one stroke are in fluid communication with one another whereas the air springs functioning oppositely of the same pair of rocker arm structures are in fluid communication with one another. For example, the air springs 152 and 154 are in fluid communication with one another by means of a flexible tube or conduit 166 whereas the air springs 144 and 156 are in communication with one another by means of the conduit 168. Also, it will be understood each of the air springs 144 extending across the .rocker arm structure 76 are in fluid communication with each other, the same arrangement being provided for the other air springs 152, 154 and 156. A suitable source of air pressure generally designated at 170 supplies air under pressure through a valve 172 to a manifold 174. The manifold 174 communicates with the conduit 166 by an auxiliary manifold 176 whereas auxiliary manifold 178 provides fluid communication between a manifold 174 and the conduit 168. The auxiliary manifold 176 is provided with a valve 180 and a gauge 182 whereas the auxiliary conduit 178 is provided with a valve 184 and gauge 186. Similarly the air springs for the lower pair of rocker arms 58 and 60 are in communication with the manifold 174 through similarly arranged conduits and auxiliary manifolds.

When the needle loom is started, the valve 172 is in the closed position Whereas the valves 180 and 184 are open to atmosphere so that there is only atmospheric pressure within the air springs. Once the needle loom is operating, then the valves 180 and 184 are closed to atmosphere but open to the source of air pressure 170 to permit the flow of compressed air into the respective air springs. When the gauges have reached a predetermined value indicating a predetermined mean pressure in the air springs, valves 180 and 184 are closed and thus the air springs are loaded to a specific desired spring constant. By operation of any of the individual valves, the spring constant for any set of air springs can be varied with respect to another set of air springs.

FIGURES 9 through 16 inclusive illustrate various modifications of spring means capable of being utilized with the needle loom heretofore described. The diagrammatic views illustrated in FIGURES 9 through 16 disclose a single rocker arm structure, for example, the rocker arm structure 76, pivoted at P to the frame structure 10 and having the needle board 70 mounted on one end thereof. FIGURE 13 illustrates the specific example described with respect to FIGURES 1 through 3, inclusive, wherein air springs are placed on both sides of the pivot P between the rocker arm structure and the frame structhe broken line B (FIGURE 10).

compression springs or tension springs or'both com-' Suitable bolts and structure and extending pression and tension springs. 153 carried by'the rocker arm through suitable apertures provided in the frame structure may be utilized to retain the springs 144' and 152' in position.

FIGURE 14 illustrates a modified use of air springs wherein two separate air springs 144" and 152 separated by a portion 10' of the frame structure 10 are arranged one above the other and are capable of functioning iden tically with the air springs 144 and 152. In the modification shown in FIGURE 14, the rocker arm structure is provided with a yoke having a bearing plate 192 extending over the upper air spring 144". The yoke 190 is provided with'bolt members 193 at each of its end whichslidably pass through apertures in'the portion 10' of frame structure 10 and is secured in a suitable manner to the rocker arm structure 76. When the rocker arm structure 76 of FIGURE 14 moves in a counterclockwise direction, the upper air spring 144" is compressed by the bearing plate 192 of the yoke 190 whereas the lower air spring 152" is expanded. Clockwise move ment reverses the operation in that the lower air spring 152" is compressed while the upper air spring 144" is expanded.

FIGURE 15 illustrates a modification similar to that of FIGURE 14 except the yoke 190' is fixed to the frame structure 10 and has two bearing plates 195 and 197 fixed thereto.

FIGURE 11 illustrates a modification similar to FIG- URE 14 but utilizing a pair of coil springs 144" and 152'." separated by the portion 10 of frame structure 10. A bearing plate 192' carried on the upper end of a bolt 190 compresses the spring 144' upon counterclockwise movement of the rocker arm structure 76 just as in the examples shown in FIGURE 14.

FIGURES 9 and 10 illustrate the use of a leaf spring 200 between the frame structure 10, the leaf spring being capable of functioning so as to store up potential energy and release kinetic energy upon movement of the rocker arm structure in either direction during its stroke. In more detaiL'the rocker arm structure 76 is provided with a-pin 202 extending upwardly through a suitable aperture :in leaf spring 200, the pin 202 having a stop member 204 thereon. Upon movement'of the rocker armstructure 76 in a clockwise direction, as viewed 'in FIGURE'9, the spring will engage a shoulder 206 on the pin 202 and be urged upwardly as indicated by the broken line A (FIGURE 10). Upon counterclockwise movement, the stop member 204 of the pin engages the opposite side of the spring and moves it to the position shown by It will be understood that such movement to either A or B stores up potential energy and converts potential energy into kinetic energy upon changing direction of the stroke of the rocker arm structure so that the kinetic energy can be effectively uniformly distributed across the needle board to provide the results described in detail with respect to FIGURES 1 through 3, inclusive.

FIGURE 16 illustrates diagrammatically a spring means wherein a steel torsion bar spring 181 is used in series with air springs 143. The rocker arm assembly 76 carrying needle board 70 is. rigidly fixed to the torsion bar spring 181 and is pivoted at bearing P to the frame 10. An arm member 183 having an axis transverse of the axis of the torsion bar spring is fixed to an end of the torsion bar spring 181 and also at its free ends to two pairs of air springs 143 which are in turn mounted on the frame 10. In this arrangement the loom can be started with low air pressure in the air springs, thus the motion 'mass, consistent with structural rigidity,

form distribution of driving of the structure 183 will substantially follow that of the rocker arm structure 76 and the torsion spring will be ineffective. After the oscillation of the needle board has been started, air pressure in the air springs can be increased to the point where the structure 183 is substantially still and the torsion bar spring is driving the rocker arm assembly 76.

For minimum stresses and forces it is desirable that the rocker arm structures 76 have a minimum weight or particularly in areas of maximum motion, that is near the needle board. This is a feature of the needle loom of the present invention. By the arrangement of FIGURE 16, the weight of air springs and their yoke structures is eliminated from the rocker arm assemblies.

FIGURE 17 illustrates diagrammatically applying spring means to a needle loom of the type wherein the needle board is oscillated in a linear motion path'by a conventional crank means. Heretofore, needle looms of this type were limited in their speed of operation in that the force created on the needle board at the end of its stroke due to the deceleration and acceleration when it was changing direction caused the needle board to flex and crank bearing to be overloaded. By application of the spring means between the needle board and the frame structure of the needle loom, as heretofore described, uniforces is provided to the needle board to thereby eliminate flexure of the needle board and assist the crank driving means to properly oscillate the same. In more detail, the needle board 210 is reciprocated vertically in a linear motion by means of a pair of oppositely rotating crank arms 212 and 214. The crank arms 212 and 214 are connected to the needle board 210 by means of connecting rods 216 and 218, and guide rods 217 and 219, respectively. A plurality of spring means 220 are provided across the needle board 210, the spring means 220 being capable of storing up potential energy and releasing potential energy in both directions of the stroke. In the particular example shown in FIG- URE 17, the spring means 220 is of the same type 'as shown in FIGURE 14 and includes pairs of air springs 222 and 224 separated by a portion 226 of the flame structure of the needle loom. A yoke structure 228 pr vided between the needle board 210 and the upper air spring 224 causes the upper air spring to compress when the needle board 210 is moved in a vertically downward direction. The other air springs 220 directly between the needle board 210 and the portion 226 of the frame structure 227 compress when the needle board is moving vertically upwardly. Such an arrangement as just described results in a uniform application of forces across the needle board at each end of its stroke and thereby assists the crank to overcome the forces due to inertia of movement of the needle board.

It will be understood that the guide rods 217 and 219 could be extended and connected to another needle board not shown but fitted with springs in a manner similar to that just described.

Referring now to FIGURES 4 through 8 inclusive, still further modification of the needle loom of the present invention is illustrated, this modification being capable of even higher production than the needle looms just previously described. In FIGURE 4, which illustrates a vertical end view partly in section of the modified needle loom, it will be noted that there are four rocker arm structures 230, 232, 234 and 236 pivotally mounted on the frame structure 238 for oscillating angular motion about spaced pivotal axes 240, 242, 244 and 246, respectively. The pivotal axes of the rocker arm structures are vertically spaced from each other and lie in a common vertical plane extending transverse of the length of the web 248 passing through the needle loom. Each pivotal axis is intermediate 'and midway between the ends of its respective rocker arm structure.

Each rocker arm structure carries a needle board 250 at its opposite ends.

The needle boards 250 of the upper pair of rocker arm structures 230 and 232 are arranged to oppose each other and likewise the needle boards 250 of the lower pair of rocker arm structures 234 and 236 are arranged to oppose each other. In effect, there are four pairs of opposed needle boards 250 which the web 248 passes through and thus the web is penetrated simultaneously at four different places, two of the places being from one side of the web and the other two places being from the other side of the web. Guide plates 252 and 254 suitably supported on the frame structure are provided between each pair of needle boards 259 for guiding the web therebetween, the guide plates having the usual holes therein for passage of the needles therethrough.

As shown diagrammatically in broken lines, a pair of crank cams or arms 256 and 258 are each provided with a pair of eccentrics, the crank cams or arms 256 and 258 being spaced equally from the vertical plane through the axes of the rocker arm structure and also equally from a horizontal plane positioned midway between the upper pair of rocker arm structures and the lower pair of rocker arm structures. Connecting rods 260 and 262 pivotally connected to the two eccentrics of crank cam or arm 256 are of equal length and are both pivotally connected to the respective lower rocker arm structures 232 and 236 of the upper and lower pairs of the same. The connecting rods 260 and 262 are connected to eccentrics of the crank cam or arm 256 which are outof-phase with each other and thus the connecting rods always operate to move the rocker arms 232 and 236 in opposite directions about their pivotal axes 242 and 246.

A pair of connecting rods 264 and 266 are respectively connected to the rocker arm structures 230 and 234 as well as to eccentrics of the crank cam or arm 258. The connecting rods 264 and 266 likewise are of equal length to each other and to the connecting rods 260 and 262 and move opposite to each other and thus move the upper rocker arm structures 230 and 234 of the pairs in opposite directions at all times. Crank cams or arms 256 and 258 are driven in the same direction by means of a belt drive 270 or the like, it being understood that a suitable source of power is connected to one or the other or both of the crank arms.

As will now be evident, the needle loom shown in FIGURE 4 is a completely balanced system both vertically and horizontally as all forces created by rotation of the crank arms 256 and 258 and movement of the needle boards 250 and their respective rocker arm structures are equal and opposite in vertical directions as well as horizontal directions.

A slightly modified spring system is illustrated in FIG- URES 4 to 8 for storing up potential energy and releasing kinetic energy uniformly across the needle boards on both sides of the needle loom. In more detail, each rocker arm structure is provided with a pair of double acting air springs positioned on either side of its pivotal axis. A description with respect to one rocker arm structure and its needle boards will sufiice for all rocker arm structures.

Referring in detail to FIGURES 5 through 8, the rocker arm structure 230 is provided with a center axle member 272 suitably journalled in bearings (not shown) supported in the side of the frame structure of the needle loom. Spaced across and carried by the axle member 272 are a plurality of spars 274 which support at their outer ends the needle boards 250 in any suitable manner. Intermediate the respective outer ends of the spars 274 and the axle member are crossbeams 276. Each of the cross-beams 276 are positioned immediately beneath a channel-shaped cross-beam 278 extending between the sides of a frame structure 238. One air spring 280 is supported on the upper side of the beam 278 whereas another air spring 282 is supported immediately beneath the cross-beam between the cross-beam 278 and the cross-beam 276 of the rocker arm structure. A yoke structure generally designated at 284 and having a pair of rods 286 extending upwardly through suitable apertures 288 in'the beam 278 is provided with a bearing plate at 290 for engaging the top side of the uppermost air spring 280. e

As shown in FIGURE 7, the cross-beam member 278 is provided with fittings 292 having suitable passages 294 and 296 therein, the fittings being adapted to threadedly receive the upper and lower air springs 280 and 282, respectively. Air pressure may be adjustably supplied to the air springs through the passages 294- and 296 by suitable conduits or flexible tubing 298 and 300 in a manner similar to that previously described.

As will now be apparent, equal and oppositely directed kinetic energy may be applied uniformly to the respective needle boards on the outer ends of the rocker arm structures as the rocker arm structures oscillate between their predetermined limits of oscillations as determined by their crank drive mechanism. It will be appreciated that the forces of the spring means coacting with one rocker arm structure of one pair is equal and opposite to the forces created by the spring means co operating with the other rocker arm structure of a pair. Since the upper half of the needle loom is identical to the lower half, that is, its mirror image of the same, andoperates in an opposite direction, there is also balancing of forces between the pairs of rocker arm structures as they oscillate.

It has been found highly desirable to have the needles of the opposed pairs extending at an angle to theweb pass ing therebetween. The needles of an opposed pair of needle boards on one side of the vertical plane through the axes of the rocker arm structures extend toward the needles of the corresponding pair of opposed needle boards on the other side of the plane. The angle at which the needles extend relative to the horizontal is determined in a manner similar to that heretofore described with respect to the angle of the needles of the needle boards of the needle loom shown in FIGURES 1 to 3, inclusive. In other words, the path of penetration of the needle through the web is a tangent to an arc having a radius equal to the distance between the pivotal axis and the needle.

While the objects and the advantages of the needle loom of the present invention have been fully and effectively accomplished by the apparatus disclosed herein, it will be understood that such needle looms are subject to some changes and modifications without departing from the principles and scope of the invention involved. Therefore, the terminology used in the specification is for the purpose of description and not limitation, the scope of the invention being defined by the claims.

What is claimed is:

1. In a machine for needling a web of loosely matted fibers and producing a needled fabric: a frame structure; means for advancing the web through said frame structure; a needle board carrying an array of needles; means for moving said needle board to and'fro between predetermined points so that said array of needles penetrate in and are withdrawn from the web; a first spring means operatively positioned between said needle board and said frame for storing up energy when said needle board travels in one direction to apply a uniform driving force across said needle board when said needle board moving means is changing direction of travel of the needle board to an opposite direction; and a second spring means operatively positioned between said needle board and said frame structure for storing up energy when the needle board is traveling in the opposite direction'to apply a uniform driving force across said needle board when said needle board moving means is changing direction of travel of the needle board to said one direction.

2. In' a machine for needling a web of loosely matted fibers and producing a needled fabric: a frame structure;

means for advancing the web through said frame structure; a needle board carrying an array of needles; means for moving said needle board to and fro between predetermined points so that said array of needles penetrate in and are withdrawn from the web; a first spring means operatively positioned between said needle. board and said frame for storing up energy when said needle board travels in one direction to apply a uniform driving force across said needle board when said needle board moving means is changing direction of travel of the needle board to an opposite direction; a second spring means operatively positioned between said needle board and said frame structure for storing up energy when the needle board is traveling in the opposite direction to apply a uniform driving force across said needle board when said needle board moving means is changing direction of travel of the needle board to said one direction; and means operative while said needle board is moving for changing the effective spring constant of said first and second spring means.

3. In a machine for needling a web of loosely matted fibers and producing a needled fabric: a frame structure; means for advancing the web through said frame structure; an elongated needle board extending transversely of the web and carrying an array of needles; means oscillating said needle board to and fro between predetermined points so that said array of needles penetrate in and are withdrawn from the web, said last-mentioned means including means connected to said needle board at longitudinally spaced positions of the same for effecting to and fro movement; and spring means effective at each of said predetermined points to apply a uniform driving force across said needle board to assist said needle board moving means in changing direction of travel 'of said needle board at each of the said predetermined points.

4. The machine of claim 3 wherein said means connected to said needle board includes arocker arm structure and wherein said spring means comprises a torsion bar spring rigidly connected to said rocker arm structure and operatively connected to said. frame structure so that said needle board oscillates to and fro. in an angular motion path, an arm member rigidly connected to said torsion bar spring and having an axis transverse of the axis of said torsion bar spring and air spring means be'- tween said arm member and said frame structure, said air spring means being arranged to resist turning of said torsion bar spring about its axis in either direction. 5. The machine of claim 4 including means to adjust air pressure of said air spring means while said needle board is oscillating.

6. The machine of claim 4 wherein said arm member is connected intermediate its ends to said torsionbar spring and wherein said air spring means includes a first pair of air springs, one air spring of said first pair being positioned between said frame structure and one side of one end of said arm member and the other air spring of said first pair being positioned between said frame structure and the opposite side of same end of said arm member; and a second pair of air springs, one air spring of said second pair being positioned between said frame structure and one side of the opposite end of said arm member and the other air spring of said second pair being positioned between said frame structure and the opposite side of the opposite end of said arm member.

7. The machine of claim 6 including means to adjust air pressure of the air springs of said first and second pairs 'while said needle board is oscillating.

8. The machine of claim '3 wherein said spring means includes a plurality of pairs of air springs, one of each of said pairs of air springs storing energy between said needle board and said frame structure on movement of said needle board in one direction and the otherof each of said pairs of air springs storing energy between said needle board (and said frame structure upon movement of the needle board in an opposite direction.

-by one of the air springs movement of the needle board in one direction 15 9. The machine of claim 8 wherein said needle board includes rocker arms having a pivotal axis whereby the needle board oscillates to and fro in an angular motion path and wherein said one air spring of each of said pairs is positioned forward of the pivotal axis between the frame structure and the rocker arm and said other air spring of each of said pairs is positioned rearwardly of the pivotal axis between the rocker arm and the frame structure.

10. The machine of claim 8 wherein said needle board includes rocker arms having a pivotal axis whereby the needle board oscillates to and fro in an angular motion path and wherein said one air spring and said other air spring of each pair are arranged one above the other, said frame structure having a portion interposed between said one air spring and the other air spring of each pair whereof each pair is storing energy and said frame structure upon and the other air spring of each pair is storing energy between said needle board and said frame structure upon movement of the needle board in an opposite direction.

11. The machine of claim 8 wherein said needle board includes rocker arm structure having a pivotal axis where by the needle board oscillates to and fro in an angular between the needle board motion path and wherein said one air spring and said other air spring of each of said pairs of air springs are arranged on opposite sides of said rocker arm structure, and a yoke member fixed to said frame structure for each of said pairs of air springs, each yoke member having a first bearing plate engaging said one air spring of one pair of air springs on a side opposite the side engaging said rocker arm structure and -a second bearing plate engaging said other air spring of the same pair of air springs on a side opposite its side engaging said rocker arm structure.

12. The machine of claim 3 wherein said spring means includes at least one leaf spring positioned between said frame structure and said needle board and capable of storing energy between said needle board and said frame structure upon movement of said needle board in either direction.

13. The machine of claim 3 wherein said spring means includes a plurality of pairs of coil springs, one of said coil springs of each of said pairs of coil springs being arranged between said needle board and said frame structure so as to store energy between said needle board and said frame structure upon movement of said needle board in one direction and the other coil spring of each of said pairs of coil springs storing energy between said needle board and said frame structure upon movement of said needle board in an opposite direction.

14. The machine of claim 13 'wherein each pair of coil springs is arranged on a common axis, said frame structure having a portion interposed between each pair of coil springs whereby one coil spring of each pair stores energy upon movement of said needle board in one direction and the other coil spring of each pair stores energy upon movement of said needle board in the opposite direction.

15. The machine of claim 13 wherein said needle board includes rocker arms having a pivotal axis whereby the needle board oscillates to and fro in an angular motion path and wherein said one coil spring of each of said pairs is positioned forward of rocker arms of said frame structure and the other coil spring of each of said pairs is positioned between the rocker arms and the frame structure rearwardly of said pivotal axis.

16. In a machine for needling a web of loosely matted fibers and producing a needled fabric: a frame structure; means for advancing the web through said frame structure; a rocker arm structure pivotally mounted intermediate its ends to said frame structure on a pivotal axis extending substantially transverse of the web; at least one elongated needle board carried by said rocker arm structhe pivotal axis and the ture adjacent one of its ends, said elongated needle board verse of the Web; an array of needles carried by said needle board; means connected to said rocker arm structure for oscillating the same between predetermined points and thereby causing the array of needles to penetrate and be withdrawn from the web; and means for uniformly storing up potential energy between said needle board and said frame structure during movement of said needle board in both directions and respectively releasing uniform kinetic energy across the needle board in an op posite direction at each end of the stroke of travel of the needle board.

17. The machine of claim 16 wherein said last-mentioned means includes at least one air spring positioned between said frame structure and said rocker arm forward of said pivotal axis and at least one air spring positioned between said frame structure and the same side of said rocker arm structure rearwardly of said pivotal axis, and means connected to each air spring for adjusting air pressure of the air spring while said rocker arm structure is oscillating.

18. The machine of claim 16 wherein said last-mentioned means includes at least a pair of air springs arranged one above the other, said frame structure having a portion thereof extending between the air springs of the pair, one of the air springs of the pair being positioned between the rocker arm structure and the frame structure and adapted to be compressed upon movement of the rocker arm structure in one direction and the other air spring of the pair being operatively connected to the rocker arm structure wherein the same is compressed upon movement of the rocker arm structure in an opposite direction and means connected to each air spring of said pair for adjusting air pressure in the same while said rocker arm structure is oscillating.

19. In a machine for needling a web of loosely matted fibers and producing a needled fabric: a frame structure; means for advancing the web through said frame structure; a rocker arm structure pivotally mounted intermediate its end to said frame structure on a pivotal axis extending substantially transverse of said web; an elongated needle board carried by said rocker arm structure adjacent one of its ends; a second elongated needle board carried by said rocker arm structure adjacent the other of its ends, both said elongated needle boards having longitudinal axes extending substantially parallel to each other and transverse of the web, each of said needle boards having an array of needles; means connected to said rocker arm structure for oscillating the same between predetermined points and thereby causing alternate penetration of the web by the respective needle boards; and means for uniformly storing up potential energy between each of said needle boards and said frame structure during movement of said needle boards in both directions and respectively releasing uniform kinetic energy across each of the needle boards in an opposite direction at each end of the stroke of travel of each of the needle boards.

20. The machine of claim 19 including means for adjusting said last-mentioned means while said rocker arm structure is oscillating about its pivotal axis.

21. In a machine for needling a web of loosely matted fibers and producing a needled fabric: a frame structure; a first pair of spaced rocker arm structures pivotally mounted intermediate their ends on said frame structure and having spaced parallel pivotal axes; a second pair of rocker arm structures pivotally mounted intermediate their ends on said frame structure and having spaced parallel pivotal axes, the pivotal axes of said first and second pairs of rocker arm structures lying in a common plane, a pair of opposed elongated needle boards carried respectively on the corresponding ends of said first pair of rocker arm structures; a second pair of opposed elongated needle boards carried respectively on the corresponding ends of said second pair of rocker arm structures; each of said needle boards of each pair of needle boards having an array of needles; means for advancing the web through said frame structure between said first pair of opposed needle boards and then between said second pair of needle boards; and means for oscillating said first pair of rocker arm structures between prede termined points and said second pair of rocker arm stiuctures between predetermined points whereby needles of said first and second pairs of opposed needle boards each respectively effect penetration of the web alternately from opposite sides of the same.

22. The machine of claim 21 wherein said last-mentioned. means includes crank means; at least one con necting rod connected to said crank means and operatively connected to said first pair of rocker arm structures; a second connectingrod connected to said crank means and operatively connected to said second pair of rocker arm structures, said first and second connecting rods being connected to said crank means 180 out-of-phase with each other whereby forces created by oscillation of said pairs of needle boards are equal and opposite and thereby balanced.

23. The machine of claim 21 wherein said last-mentioned means includes a first link pivotally connected to each rocker arm structure of said first pair; a second link pivotally connected to each rocker arm structure of said second pair; crank means, a first connecting rod connected to said crank means and to said first link; a second connecting rod connected to said crank means and said second link, said first and second connecting rods being connected to said crank means 180 out-of-phase with each other whereby forces created by oscillation of said pairs of needle boards are equal and opposite and thereby balanced.

24. The machine of claim 21 including means for uniformly storing up potential energy between each rocker arm structure of each of said pairs of rocker arm structures during oscillation of said rocker arm structures in both directions and respectively releasing uniform kinetic energy across each of the rocker arm structures in an opposite direction at the end of the stroke of travel of the same.

25. The machine of claim 24 wherein said means includes a plurality of air springs coacting between said frame structure and the rocker arm structures of. said first and second pairs, half of said air springs being compressed upon oscillation of the rocker arm structures in one direction and the other half being compressed upon oscillation of the rocker arm'structures in an opposite direction.

26. The machine'of claim 25 including means to adjust air pressure in said air springs while said pairs of rocker arm structures'are oscillating, said last-mentioned means including a source of air pressure, fluid connecting means between said source of air pressure and said air springs and valve means in said fluid connecting means.

27. The-.machine'of 'claim'21 wherein said last-mentioned means includes a first crank means spaced from one side of the common plane in which the pivotal axes of the first and second pairs of rocker arm structures lie; a second crank means spaced from the opposite side of the plane; a first connecting rod connected to said first crank means and to one rocker arm structure of said first pair, a second connecting rod connected to said first crank means and to a corresponding rocker arm structure of said second pair of rocker arm structures; a third connecting rod connected to said second crank means and to the other rocker arm structure of said first pair of rocker arm structures; and a fourth connecting rod connected to said second crank means and to the other rocker arm structure of said second pair of rocker arm structures, said first and second connecting rods and said third and fourth connecting rods being of equal length and connected to said first and second crank means respectively 18 out-of-phase whereby forces created by oscillation of said pairs of needle boards are equal and opposite and thereby balanced.

28. The machine of claim 21 wherein said first pair of opposed needle boards is arranged vertically above said second pair of opposed needle boards.

29. A needle loom for needling a web of loosely matted fibers comprising: a frame structure; a first pair of opposed elongated needle boards each having an array of needles; a second pair of opposed elongated needle boards positioned above said first pair and each having an array of needles; means supporting each of said pairs of needle boards respectively in said frame structure for oscillating angular motion about vertically spaced axes; means operatively connected to said supporting means of each pair of needle boards'for simultaneously oscillating. said pairs of needle boards in opposite directions whereby forces exerted on said frame structure by both pairs of needle boards is equal and opposite and means for feeding the web successively between first and second pairs of needle boards whereby the web is alternately penetrated from each side by the array of needles of each needle board of each pair of needle boards.

30. The needle loom of claim 29 including a plurality of air springs carried by said frame structure, at least one air spring cooperating with each needle board on oscillation of the same in one direction to compress and store up potential energy and then release kinetic energy at the end of the stroke of the needle board and at least one of said air springs cooperating with said needle board when said needle board is oscillating in an opposite direction to compress and store up potential energy and release kinetic energy when the needle board reaches the end of itsstroke in the opposite direction.

31. The needle loom of claim 30 including means to adjust air pressure in said air spring when said pairs of needle boards arev oscillating.

32. A needle loom for needling a web of loosely matted fibers comprising: a frame structure; a first rocker arm structure and a second rocker arm structure, said first rocker arm structure being pivotally mounted in said frame structure intermediate and midway between its ends and said second rocker arm structure being pivotal. ly mounted in said frame structure intermediate and midway between its ends, the first and second rocker arm structures having vertically spaced parallel horizontal pivotal axis; a needle board carried on each end of each of said first and second rocker arm structures and each needle board having an array of needles, the needle boards on corresponding ends of said first and second rocker arm structures opposing each other; a third rocker arm structure and a fourth rocker arm structure, said third rocker arm structure being pivotally mounted in said frame structure intermediate and between its ends and said fourth rocker armstructure being pivotally mounted in said frame-structure intermediate and between its ends, said third and fourth rocker arm structures having vertically spaced parallel horizontal pivotal axes lying in a common plane with and spaced vertically from the pivotal axes of said first and second rocker arm structures; a needle board carried on each end of each of said third and fourth rocker arm structures, and each having an array of needles, the needle boards on the corresponding ends of said third and fourth rocker arm structures opposing each other; means for oscillating said first and second rocker arm structures simultaneously in the same direction while oscillating said third and fourth rocker arm structures simultaneously about their pivotal axes 180 out-of-phase with the oscillation of said first and second rocker arm structures; and means for advancing the web horizontally between the needle boards of said first and second rocker arm structure and then horizontally between the opposed needle boards of said third and fourth rocker arm structures.

33. The needle loom of claim 32 wherein each of said rocker arm structures includes an axle member and a plurality of horizontally spaced spar members carried on said axle member, the needle boards being supported at the ends of the spar members.

34. The needle loom of claim 33 including a plurality of air spring means, at least two air spring means being supported between each spar member and said frame structure on opposite sides of said axle member, each air spring means being capable of storing up potential energy upon oscillation of the rocker arm structure in both directions and releasing potential energy upon oscillation in the respective opposite directions.

35. The needle loom of claim 34 including means to effectively adjust the spring constant of said air spring means while the needle loom is operating.

36. The needle loom of claim 32 wherein the array of needles of the opposed needle boards on corresponding ends of the first and second, and third and fourth rocker arm structure respectively arranged to penetrate the web in a path at an angle to and opposite to a path of penetration of opposed needle boards at the opposite corresponding ends of said first and second, and third and fourth rocker arm structures, respectively.

37. The needle loom of claim 32 wherein said oscillating means includes crank means, a plurality of connecting rods, one of said connecting rods being connected between crank means and each of said first, second, third and fourth rocker arm structures.

38. The needle loom of claim 37 wherein each of said connecting rods is of equal length.

39. In a machine for needling a web of loosely matted fibers and producing a needled fabric: a frame structure; a pair of elongated needle boards each carrying an array of needles, the array of needles of one of said needle boards opposing the array of needles of the other of said needle boards; means for advancing a web through said frame structure between the array of needles of said needle boards; means for simultaneously moving said needle boards to and fro between predetermined points so that there is alternate penetration of the web from opposite sides by the respective arrays of needles of said pair of needle boards; a first spring means operatively positioned between each of said pair of needle boards and said frame structure for storing up energy when said pair of needle boards travel in one direction and for releasing the stored up energy and applying the same as a uniform driving force across each of said pair of needle boards when said needle boards are changing direction of travel to an opposite direction; and a second spring means operatively positioned between each of said pair of needle boards and said frame structure for storing up energy when said pair of needle boards travel in the opposite direction and for releasing the stored up energy and applying the same as a uniform driving force across each of said pair of needle boards when said pair of needle boards are changing direction of travel to said one direction.

40. The machine of claim 39 wherein said means simultaneously moving said needle boards includes means to move said pairs of needle boards in a linear path.

41. The machine of claim 39 wherein said means for simultaneously moving said pair of needle boards includes means to move each of said pair of needle boards in an angular motion path, the angular motion path of one of said pair of needle boards being a mirror image path of the other of said pair of needle boards.

42. The machine of claim 39 wherein said first and second spring means each includes air springs and means to apply air pressure to said air springs after the machine is operating.

43. A needle loom for needling a web of loosely matted fibers comprising: a frame structure; a first pair of opposed elongated needle boards; a second pair of opposed elongated needle boards positioned vertically above said first pair; a third pair of opposed elongated needle boards horizontally spaced from said first pair; a fourth pair of opposed elongated needle boards positioned vertically above said first pair of needle boards, each needle board of said pairs of needle boards having an array of needles; means for simultaneously oscillating all of said pairs of needle boards in said frame structure between predetermined points with said first and third pairs moving in mirror image paths of said second, and fourth pairs respectively and with said first and second pairs moving in opposite direction from the directions of movement of said third and fourth pairs respecticely; and means for feeding a web successively between the pairs of needle boards whereby the web is alternately penetrated from each side by the respective array of needles of each needle board of each pair of needle boards.

44. The needle loom of claim 43 wherein each pair of needle boards has an equal mass and an equal inertia with respect to each of the other pairs of needle boards whereby the needle loom is balanced vertically and horizontally.

45. The needle loom of claim 43 including drive means for said oscillating means, said drive means including a drive shaft, a main motor operatively connected to said drive shaft, an auxiliary starter motor, and a fluid coupling connecting said auxiliary motor to said drive shaft whereby said auxiliary motor may be disconnected after said main motor and said auxiliary start the loom.

References Cited in the file of this patent UNITED STATES PATENTS 202,252 Field Apr. 9, 1878 1,720,574 Schieferstein July 9, 1929 2,004,709 Phillips June 11, 1935 2,004,725 Johnson June 11, 1935 2,217,967 Phillips Oct. 15, 1940 2,601,432 Clements June 24, 1952 2,845,687 Howard Aug. 5, 1958 2,896,302 Costello July 28, 1959 2,936,064 Schuessler May 10, 1960 2,993,585 Musschoot July 25, 1961 3,047,306 Easton July 31, 1962 UNITED STATES PATENT OFFI CE CERTIFICATE OF CORRECTION Patent No. 3 132,406 May 12, 1964 Alexander M, Smith 11 It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the grant lines 2 and 12 and in the heading to the printed specification, line 4 name of assignee for "Fiberwoven Corporation" each occurrence, read The Fiberwoven Corporation Signed and sealed this 27th day of October 1964.,

(SEAL) Attest:

' ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents

Claims (1)

1. IN A MACHINE FOR NEEDLING A WEB OF LOOSELY MATTED FIBERS AND PRODUCING A NEEDLED FABRIC: A FRAME STRUCTURE; MEANS FOR ADVANCING THE WEB THROUGH SAID FRAME STRUCTURE; A NEEDLE BOARD CARRYING AN ARRAY OF NEEDLES; MEANS FOR MOVING SAID NEEDLE BOARD TO AND FRO BETWEEN PREDETERMINED POINTS SO THAT SAID ARRAY OF NEEDLES PENETRATE IN AND ARE WITHDRAWN FROM THE WEB; A FIRST SPRING MEANS OPERATIVELY POSITIONED BETWEEN SAID NEEDLE BOARD AND SAID FRAME FOR STORING UP ENERGY WHEN SAID NEEDLE BOARD TRAVELS IN ONE DIRECTION TO APPLY A UNIFORM DRIVING FORCE ACROSS SAID NEEDLE BOARD WHEN SAID NEEDLE BOARD MOVING MEANS IS CHANGING DIRECTION OF TRAVEL OF THE NEEDLE BOARD TO AN OPPOSITE DIRECTION; AND A SECOND SPRING MEANS

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