US2855877A - Apparatus for forming a continuous series of stitches in a predetermined pattern - Google Patents

Description

Oct. 14, 1958 J. WHITEHEAD 2,855,877

APPARATUS FOR FORMING A CONTINUOUS SERIES OF STITCHES IN A PREDETERMINED PATTERN Filed Feb. 21, 1955 I 5 Sheets-Sheet 1 IN l E N TOR ATTORNE Y Oct. 14, 1958 J. WHITEHEAD APPARATUS FOR FORMING A commuous SERIES OF Filed Feb. 21, 1955 STITCHES IN A PREDETERMINED PATTERN 5 Sheets-Sheet 2 lNVENTOR A TTOENE Y Oct. 14, 1958 J. WHITEHEAD APPARATUS FOR FORMING AVCQNTINUOUS SERIES OF 'STITCHES IN A PREDETERMINED PATTERN 5 Sheets-Sheet 3 Filed Feb. 21, 1955 l/ENTOR- BY Mm. L)-

OCKS ATTORNEY Oct. 14, 1958 J. WHITEHEAD APPARATUS FOR FORMING A CONTINUOUS SERIES OF STITCHES IN A PREDETERMINED PATTERN 5 Sheets-Sheet 4 Filed Feb. 21, 1955 INVENTO/Z BY 5%. w.

OCKS

United States Patent APPARATUS FOR FORMING A CONTINUOUS SERIES OF STITCH-HES IN A PREDETERMINED PATTERN John Whitehead, Wembley, England Application February 21,1955, Serial No. 489,641

(Ilaims priority, application Great'Br-itain February 23, 1954 5. Claims. (Cl. 112-2) pattern produced and also the lengthof each individual.

formed of three parts, a top, a bottom and a side panel or: border which extends around the entire periphery of the mattress. The side panels are customarily formed of several layers of material, the outer layer of which exhibits stitches that follow a relatively complicated predetermined path constituting a pattern to enhance the appearance of the mattress. The stitching serves also to secure together the various layers of. material and the fact that it is arranged as a comparatively complicated pattern increases the stiffness of the side panels.

In previously known apparatus for forming stitch patterns on the side panels of mattresses the. panels have been fed through the machine rectilinearly at a constant speed and the stitch making mechanism of the sewing machine is bodily displaceable with a motion having a variable component both parallel with the direction of feed of the panels and in a direction transverse to this direction of feed. It. will be apparent that by suitably proportioning said two components of motion and/or by varying the speed at which the panels are fed through the machine a continuous line of stitches is formed along the panels, the line following a complex path which extends both longitudinally and transversely of the panelsl In practice the movement of the stitch making mechanism is obtained by moving the sewing machine bodily. The sewing machine is mounted upon a first trolley which is capable of bieng reciprocated in a first direction relative to the side panels and is itself mounted on a second trolley which is capable of being reciprocated in a direction at right angles to said first direction. The movement of the first and second trolleys are controlled from a common driving source which is connected to each of said trolleys through cam .means, the cam means being adjustable to vary the relative movement between the trolleys. The stitching mechanism of the sewing machine is also driven from said driving source.

It is a disadvantage of such previously known apparatus that it is comparatively expensive to manufacture andit has been found that by driving the trolleys and the stitch making mechanism through a gearing of fixed ratio from a single source it is not easy to obtain a large range of stitch lengths as both the shape and complexity of the pattern is varied. This is because of the numbers of stitches produced for each cycle of movement of the trolleys. has been fixed. Therefore variations in the rela- .tive movements between the trolleys to vary the size or shape ofthe pattern produced has automatically varied.

the size of each stitch,

It is, therefore, a main object of the. present invention to provide apparatus of the type specified which is easy to. manufacture and maintain in adjustment and whichineludes means for varying both the size and shape of the stitch.

According to the present invention there is provided apparatus of the type specified includingmeans for feeding material to be stitched past the stitch making mechanism of the sewing machine in a first direction and at a.

cyclically variable speed and means for bodily reciprocatingthe stitch making mechanism of the sewing machine in a direction transverse to said first direction.

Thev invention will be understood more readily from the following description of one embodiment thereof when read in conjunction with the accompanying drawings in which:

Fig. 1 shows in end elevation and part transverse section the upper part of a machine according to the invention,

Fig. 2 is a view similar to Fig. l partly in a different transverse section,

Fig. 3 is a plan view of part of the machine,

Fig. 4 is a front elevational view of the upper part of the machine, and

Fig. 5 is a back view of the machine showing the main driving motor.

Referring to the drawings, the machine comprises a supporting table 1 having a top 2 of rectangular shape which is utilised as a mount for various parts of the machine located both above and below its upper surface;

Adjacent the front edge 3 of the top 2, a flat platform 4" is arranged with its longitudinal axis parallel with said The platform 4 is movable relative to the tablefixedly mounted on the surface 2 of the table 1 so that the platform 4 may be reciprocated relative thereto as will be described later. I

A pair of driven rollers 11, 12 and a pair of idler rollers. 13, 14for the feed of material to be stitched are rotatably mounted in housings 15 and 16 on the platform at each end thereof, the axes of the rollers of each pair being substantially at right angles to the longitudinal axis of] the platform but parallel with the plane containing the top 2 of the table 1. The uppermost rollers 11 and 13 of each pair are each spring urged towards its associated lowermost rollers 12 and 14 under the action of hand operable means 17 and 18 for adjusting the pressure between the pairs of rollers. As shown in Fig. 4 of the drawings the roller 11 is rotatably mounted between the ends of levers such as 19 which are pivoted as at 20 to the housing 15. The lever 19 is formed with an extension arm 21 on the opposite side of the pivot 20 and this is pivoted to a link 22, the lower end of which is slotted to engage with a pin 23 formed on a toggle member 24 to which the handle 17 is secured. A coiled compression spring 25' extends between a fixed abutment 26 at the upper end of t through a dead centre position and thence pivot the arm 21 downwardly to cause the roller 11 to move upwardlyaway from the roller 12.

The roller 12 is driven through gears28, 29 and worm and wheel 30'and 31 by a shaft 32Whicl1. extends out- Patented Oct. 14, 1958 wardly beyond the end of the platform 4 in a direction parallel with its longitudinal axis. The shaft 32 is formed at its outer end with parallel splines 33 to engage slidably within the splined bore of a worm wheel 34 (Fig. 2). The worm wheel 34 meshes with and is driven by a worm 35 provided at one end of a drive shaft 36 mounted in bearings 37, 38 and 39 secured to the top 2 of the table 1.. The drive shaft 36 is provided at its end remote from the worm wheel 35 with a pulley 40 to be driven at a substantially constant speed through an endless belt 41 also engaging over a pulley 42 mounted on the shaft of an eletcric motor 43 supported by bracket elements 44 and 45 beneath the top 2. It will thus be apparent that as the platform 4 is reciprocated (by means to be described later), the drive to the roller 12 is maintained.

Extending transversely at right angles to the longitudinal axis of the platform 4 and to one side of it a sewing machine 46 is similarly mounted on pairs of rollers 4'7, 43, 49, 50, 51 and 52 engaging respectively with bars 53. 54 and 55' fixedly secured in spaced relationship to the top 2 of the table 1 so that the sewing machine 46 is reciprocable in a direction at right angles to the longitudinal axis of the platform 4. The needle 56 of the sewing machine 46 and the housing 57 containing the stitch making mechanism of the machine can be moved bodily transversely across the entire width of material to be stitched which is fed through the rollers 13 and 14 and the rollers 11 and 12, the needle 56 extending above the material and the housing 57 extending below the material.

The drive shaft 36 (Figs. 2 and 3) has its axis parallel with the longitudinal axis of the sewing machine 46 and the reciprocations of both this sewing machine and the platform 4 are under the control of cam means associated with this shaft. The shaft 36 passes through a gear box 58 located intermediate its length and through reduction gearing (not shown) within the box drives a shaft 59 carrying a pair of cam members 64] and 61. The cam member 6:: is formed with a groove 62 of substantially cardioid shape in which a cam follower 63 engages. The cam follower 63 is carried by a plate 64 pivoted at 65 to the top 2 of the table 1. The plate 64 is formed with a slot 66 and a link 67 is pivoted at one end 63 to the sewing machine 46 and at the other end to a pivot 69 which is capable of being secured relative to the plate 64 at any position along the length of the slot 66. Thus as the cam member 66 is rotated the sewing machine 46 is reciprocated in a direction at right angles to the longitudinal. direction of the platform 4, the magnitude of the reciprocatiens being determined by the position of the pivot 69 in the slot 66 and the acceleration of the sewing machine 46 being controlled by the shape of the groove 62.

The cam member 61 is formed with a groove 70 of substantially elliptical shape in which a cam follower 71 engages. The cam follower 71 is carried at the outer end of an arm 72 extending outwardly from the upper end of an element 73, which is pivoted relative to the top 2 of the table 1. A slotted arm 74 extends outwardly from the lower end of the element 73 to make an acute angle with the arm 72. A link 75 is pivoted at one end 76 to the platform 4 and at the other end to a pivot 77 which is capable of being secured relative to the arm 74 at any position along the length of its slot. Thus as the cam member 61 is rotated the platform 4 is reciprocated in a direction parallel with its longitudinal axis, the magnitude of the reciprocations being determined by the position of the pivot 77 in the slot of the arm 74 and the acceleration of the platform 4 being controlled by the shape of the groove 70. As illustrated in the drawings the groove 70 is substantially elliptical so that the platform 4 will execute harmonic motion.

The cam and link mechanism for reciprocating the platform 4 and the sewing machine 46 is of known type and it will be apparent that by varying the respective lengths of parts of said linkages and by varying the shape and size of the grooves formed in the cam members the relative movement between this platform and the sewing machine can be altered in a variety of ways. For example, variation in the magnitude of each stroke together with relative variation between the phases of each reciprocation can be made.

it will be apparent that feeding strips of material to be stitched through the pair of idler rollers 13, 14 and the driven rollers 11, 12 at a substantially constant speed while at the same time reciprocating the platform 4 on which these rollers are mounted causes the strips of material to be moved at a cyclically variable speed relative to the table 1 and to the fixed longitudinal axis of the sewing machine 46. Further, reciprocation of the sewing machine 46 in a direction parallel with its longitudinal axis in conjunction with this movement of the material causes the same relative movement between the stitch making mechanism of the sewing machine 46 and the material as was obtained in previously known machines in which the material is fed at a constant speed through guide rollers, the axes of which are fixed, and the sewing machine is reciprocated both in a direction parallel with its longitudinal axis and in a direction parallel with the direction of feed of the material.

The stitch making mechanism of the sewing machine 46 couldbe driven by an auxiliary motor mounted on the machine itself but it has been found preferable to drive this mechanism from the drive shaft 36 in order to obtain optimum synchronism between movement of the material and the actual stitch formation and to prevent a lag occurring when starting up the apparatus, and overrunning of the stitch making mechanism when stopping the apparatus due to differences in the inertia of separate driving means.

As shown in Figs. 1, 2, 3 and 5 of the drawings therefore the sewing machine is provided with a driving pulley 78 coupled by an endless flexible belt 79 with pulley 80. The pulley 8th is formed with a splined hub and is slidably mounted on a splined shaft 81 which is rotatably mounted between a bearing 82 on the top 2 of the table 1 and a further bearing (not shown) within the sewing machine 46. A pulley 83 is securely mounted at the outer end of the shaft 81 and is coupled by an endless flexible belt 84 with a pulley 85 mounted on the shaft of the motor 43. The pulley 83 is of the well known variable diameter type in order that the number of stitches produced by the sewing machine 46 for each cycle of reciprocation of this machine and of the platform 4 may be varied.

What I claim is:

1. Sewing apparatus for forming a continuous series of stitches in cycles of a predetermined pattern on ma terial to be stitched comprising a sewing machine, stitch making mechanism on the sewing machine, means for reciprocating the sewing machine so that said stitch makmg mechanism reciprocates rectilinearly along a first path, a platform, means for reciprocating the platform rectilinearly along a second path transverse to and cross ng said first path and means on said platform for feedlng material to be stitched continuously relative to said platform past said stitch making mechanism.

2. Sewing apparatus for forming a continuous series of stitches in cycles of a predetermined pattern on material to be stitched comprising a sewing machine, stitch making mechanism on the sewing machine, means for reciprocating the sewing machine so that said stitch making mechanism reciprocates rectilinearly along a first path, a platform, means for reciprocating the platform rectilinearly along a second path normal to and crossing said first path, a pair of driven rollers and an opposed pair of idler rollers both mounted on the platform in 5 spaced apart relationship with their axes parallel with one another and with said first path and means for continuously driving said driven rollers.

3. Sewing apparatus according to claim 2 comprising a common driving shaft extending in a direction parallel with said first path for reciprocating both the platform and the sewing machine.

4. Sewing apparatus for forming a continuous series of stitches in cycles of a predetermined pattern on material to be stitched comprising a sewing machine, stitch making mechanism on the sewing machine, means for reciprocating the sewing machine so that said stitch making mechanism recipocates rectilinearly along a first path, a platform, means for reciprocating the platform rectilinearly along a second path normal to and crossing said first path, a pair of driven rollers and an opposed pair of idler rollers both mounted on the platform in spaced apart relationship with their axes parallel with one another and with said first path and means for continuously driving said driven rollers, a common driving shaft extending in a direction parallel with said first path, a first face cam coupled to said shaft, a first annular cam surface in said first face cam and link mechanism coupled with said first cam surface for reciprocating said sewing machine, a second face cam coupled with said shaft, a second annular cam surface on said second face cam and link mechanism coupled with said second cam surface for reciprocating said platform.

- 5. Sewing apparatus according to claim 4 comprising worm and wheel gearing coupled to said driven rollers comprising a splined shaft arranged with its axis parallel with said second path, coupling between said splined shaft and said common driving shaft and worm and wheel gearing between said splined shaft and said driven rollers.

References (Iited in the file of this patent UNITED STATES PATENTS 2,059,845 Bowersox Nov. 3, 1936 2,218,785 Boettcher Oct; 22, 1940 2,382,486 Kelly Aug. 14, 1945 2,393,786 Lenartowicz et a1 I an. 29, 1946 2,483,466 Johnson Oct. 4, 1949 2,505,822 Bechik et a1 May 2, 1950

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