US2742007A - Buttonhole attachment for sewing machines - Google Patents

Description

April 17, 1956 N. T. ALMQUlsT 2,742,007

BUTTONHOLE ATTACHMENT F'OR SEWING MACHINES /40 /38 Mii/48 INVENToR. /\//L s T. ,4L Mapu/5 T A T ORNE YS April 17, 1956 N. T. ALMQUIST 2,742,007

BUTTONHOLE ATTACHMENT FOR SEWING MACHINES Filed May 8, 1955 2 Sheets-Sheet 2 FIG.4

1NV ENToR. AHL@` 7.' ALMQU/ST v TRNEY United States Patent Oce BUTToNHoLE ATTACHMENTFOR sEwlN MACHINES Nils T. Almqust, New Britain, Conn.,assignor of fifty per cent to Raymond Engineering Laboratory, Inc., Middletown, Conn., a corporation of Connecticut Application May s, 195s, seriaiNo. 353,776` Claims.` (Cl. 112-77) The present invention relates in general to attachments for sewing machines, and, more particularly to a buttonhole attachment having improved operating characteristics and providing many advantages for ordinary household use such as 'simplicity and ease of operation,

` A principal aim of the presentinvention is to provide a buttonhole attachment having a novel and improved arrangement of parts for imparting the necessary oscillatory, transverse, and longitudinal `movementseto the feed blade in order to produce the stitching required to form a buttonhole. f Y

Included in the foregoing aim is theobject of providing a buttonhole attachment utilizing a template of varying size for varying the size of the buttonhole produced in which the template is of unique construction such that the` setting of the attachment for. buttonholesnof various sizes is greatly facilitated, there being no needto dismantle the attachment to make replacements or substitutions of the template or in order to ascertain which size of template is in service at the time. i

Another object of the invention is to obvate any need for keeping on hand a number of separate and distinct templates for the various buttonholes to be made. In this connection, it is Within the contemplation of the invention `to permit the attachment to be constructed as a unitary assemblage which may be operated as such over the entire incremental range of buttonholes for which the attachment is designed.

Another object is to provide a buttonhole attachment that can easily and quickly be set or adjusted for both the desired lengthV of hole and for the proper width of stitching. j

A further object of the invention is to provide a buttonhole attachment lending itself readily to the employment4 of exterior visual means for indicatingv both the length of hole and width of stitching for which the device has been adjusted. v

A further object of the invention is to provide a means for producing an appropriate width'of stitching or bite as` it is customarily called which will be substantially linear thereby facilitatingl the manufacturing of the attachment inasmuch as alinear scale` may be resorted to for setting the width of stitching which will be proper fortheparticular size ofbuttonhole. ,i

A still further object of the invention resdesrin the provision of mechanism for intermittently gripping, the material to be stitched while the feed blade, which is part of the attachment, is not4 effecting `movement of said material. In this respect, provision is made for timing the gripping mechanism so that its movement is synchronized in such a way as to press against the material before entry of the sewing machine needle thereinto and to remain in pressural engagement with the material untily the needle is withdrawn and the material is to be shifted by the said blade, this cyclic action being, repeated throughout the formation of the buttonhole.

Other objects will be in part obvious, and inxpart pointed out more inl detail hereinaften Patented Apr. 17, 1956 The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the kapplication of which `will be indicated in the appended claims.

In the drawings:

Figure 1 is a side elevational view of one embodiment of the buttonhole attachment forming the subject matter of the instant invention, the parts thereof being in the buttonhole attachment to the position which they assume when the needle bar of the sewing machine is fully raised or retracted;

Figure 2 is a plan view corresponding to Figure 1;

Figure 3 is a fragmentary plan view of one end of the device showing the same with a cover installed;

Figure 4 is a sectional viewA taken in the general direction of line 4 4 of Figure 2;

Figure 5 is a plan view of the dial assembly by which the attachment is adjusted for various buttonholes of different sizes; and i Figure 6 is a detailed plan view of the end of the feed blade remote from the presser foot which is used in moving the material to be stitched` To illustrate the invention, the drawings show an em-y bodiment thereof in which the buttonhole attachment comprises a support or base plate 10 upon one end of which is iiXed a U-shaped frame 12 including up standing integral standards or sides 14, 16 and a connecting lower web 18, the web being anchored to thev support or base plate by means of a pair of rivets 20. Interposed between the forward ends of the standards 14 and 16 and riveted thereto by a pair of rivets 24 is a clamp 22 used for the purpose of securing the entire presser bar of a sewing machine.

Extending rearwardly from Vthe standards 14 and 16 is a platform 26 provided with downwardly directed re-` inforcing side flanges 28 and 30. The platform 26 is pinned at `its forward end 27 to the standards 14 and 16 and is riveted at its rear end` to the base plate 10, the platform having a downwardly and rearwardly directed flange 32 serving as a supporting leg at the rear' of the buttonhole attachment, there being a rivet 34 anchoring this end'of the platform to the support or base plate 10. It will be understoodthat, when using the buttonhole attachment, the conventional feeding mechanism of the sewing machine on which the attachment is mounted is rendered ineffectual by use of a cover plate (not illus,- trated). In lieu of using the sewing machine feeding mechanism, the feeding of the fabric or material in which a buttonhole is to be formed is accomplished by means of a serrated presser foot 36 carried at one end of an elongated feed blade 38 which is pivotally and slidably mounted on the underside of the base plate 10, as will be described more particularly later. In order to effect stitching of that portion of the fabric in which the buttonhole isrto be formed, it can readily be understood that the presser foot 36` must traverse a rather complex` and tortuous pattern involving longitudinal, transverse and oscillating movements. l

Of course, the above alluded to longitudinal, transverse and oscillating movements are interrelated with each other andV cannot` be completely isolated one from the other. However, for the purpose of describing the buttonhole attachment, reference will be first made to the mechanism Chiey instrumental in producing the longitudinal movement.

In order to actuate 4the device, the attachment is providedV with an actuating lever 40 pivotally supported by the standards` 14, 16 and having a bifurcated end 42 which is connectable with the needle bar of the sewing machine for movement therewith. The actuating lever is pivotally mounted intermediate its ends on a shaft 46 3 journaled in the standards 14 and 16. The lever 40 is equipped at its other end with a cam 44 having a nose portion 45 which engages a follower arm bearing the numeral 48 which is mounted for limited pivotal movement by a pivot pin 50 supported in an upstanding relation on the platform 26. A spring 52 serves as the medium by which the follower arm 48 is biased in a clockwise direction when viewed in Figure 2, the spring 52 bearing against an upstruck ear 54 on the platform 26 to prevent movement of one end of the spring, while the other end of the spring engages an upstanding flange 58 on the follower arm 48, this upstanding flange being the portion of the follower arm actually engaged by the cam nose 45.

A second upstanding flange 60, integral with the follower arm 48, contains therein a slot 62 through which a fiat pawl element 64 extends. In order to bias the pawl 64 in a proper direction, a spring 66 is connected at one end of the pawl and has its other end anchored relative to the follower arm 48, the spring in this way urging the pawl into engagement with a ratchet 68 to rotate said ratchet in a clockwise direction as viewed in Figure 2 when the arm 48 is oscillated.

For the purpose of journaling the ratchet 68 so that it may be rotated relative to the base plate 10, a bushing '70 to which the ratchet 68 is iXedly connected has its ends rotatably received in the platform 26 and said base plate 18. A knurled knob 72 has its shank threaded into the upper end of the bushing 70 so that the ratchet may be manually rotated for a purpose subsequently to be described in greater detail. A Shaft 74 is threaded into the lower end of the bushing 70 and has a pinion 76 integrally connected thereto, the pinion being formed with a depending cylindrical boss 78.

The pinion 76 and boss 78 are adapted to cooperate with a rack guide generally denoted by reference numeral 80 and which is carried by the feed blade 38. As will be explained more fully hereinafter, the shape and size of the rack guide 80 will determine the shape and size of the buttonhole which is made by the attachment. An important feature of the invention is that the rack guide 80 is formed of a plurality of elements which can be rearranged or adjusted relative to each other to change the effective size of the rack guide in a simple and easy manner without dismantling the attachment.

In the specific embodiment shown in the drawings, the feed blade 38 is provided with an opening 81 to accommodate the pinion 76 and boss 78, the opening being formed with peripheral teeth 81a arranged in the shape of a socalled keyhole type buttonhole for engagement with the pinion 76. The rack formed by the teeth 81a determines the size of the largest buttonhole which can be made with the exemplary attachment. Underneath the feed blade 38 adjacent the left-hand end of the opening 81 as viewed in the drawings is a depending post or stub shaft 82. The upper surface of the post 82 is recessed as indicated at 82a and is formed with a U-shaped flange 84 by means of which it is fastened to the feed blade 38 utilizing a plurality of rivets 86. The recessed surface 82a lies directly beneath the left-hand end of rack 81a and is provided with a U-shaped groove or track 88 which receives the boss 78 when the feed blade is in retracted position and maintains the pinion 76 in engagement with this end of the rack.

Circumscribing the cylindrical post 82 is a rotatable dial member 90 having a plurality of arcuate rack sections 92a, 92h, 92C, 92d, 92e, 92f and 92g angularly arranged at different radial distances and which lie closely adjacent the blade 38 so that they will be engageable selectively by the pinion 76 depending of course upon which one is brought into registery with the rack 81a by the setting of the dial 90. In this manner, the pinion 76 may be compelled to traverse a shorter length of travel than if the maximum length of rack 80a is traveled, these rack sections or segments serving in the capacity of transfer teeth. In this connection, it is to be observed that an arcuate section is formed at 92h which is devoid of any teeth such as those comprising the above referred to arcuate rack sections, this untoothed section permitting the pinion 76 to follow the entire contour of the rack 80. The dial member has an upper surface 91 which is disposed at the same level as the surface 82a o-f the post 82, and formed therein and registrable with the U-shaped groove or track 88 are a plurality of reversely facing grooves or tracks 94a, 94h, 94C, 94d, 94e, 941, 94g, and 94h, these grooves being of varying length to cooperate with the rack segments 92a et seq. Owing to this groove arrangement, it can be seen that the boss 78 is guided through the proper pattern by way of the groove 88 and the particular groove 94 which has been brought into registry therewith to form each side as Well as the ends of the buttonhole to be formed. In Figure 5, it will be noted that the groove 94g is the one which has been moved into registry with the lixedly located groove 88 so that the boss 78 will traverse a generally oval pattern in forming the particular buttonhole corresponding to the length governed by the disposition of both the groove 94g and its associated rack section 92g. However, more will be said about this phase of the invention during the subsequent detailed operational description.

As best seen from Figure 6, the end portion of the feed blade 38 which contains the rack 80 and which is designated by reference numeral96 is generally circular in shape. To expose a segment of the dial 90, a tlat or chorded section is removed at 98, and, by employing a Series of gauge marks 100G, 10012, 100C, 100d, 100e, 100i, 100g, and 100k disposed ninety degrees from their corresponding rack sections 92a, 92h, 92C, 92d, 92e, 92], 92g, and the untoothed section 92h, an indication may be readily conveyed to the user as to the particular size buttonhole that will be formed with any given setting of the dial 90.

At the rear or right-hand end of the attachment, when viewed in Figure 4, there is provided a downwardly turned flange 104 having an inturned ear 106. The purpose of the ange and ear is to provide support for a springpressed pivotal latch 108 comprising a finger-engaging end 110 and a bent end 112 functioning as a dog element. The dog element 112 is engageable in any one of a series of short radial slots 114 distributed circumferentially about the periphery of the dial 90. Owing to the foregoing arrangement, it is believed readily apparent that by actuating the latch 108 in a manner to disengage the dog 112, the dial member 90 may be rotated so as to bring into proper position the appropriate arcuate section 92 which will result in the production of the desired buttonhole. On the other hand, when the latch 10S is in engaged or locking position, there can be no inadvertent or accidental rotation of the dial member and it will remain at its rotatively set position.

While in the specific embodiment shown in the drawings it has been preferred to show a rack guide formed of a plurality of members in accordance with the invention in which a second part of the rack guide is brought into registry or operating position selectively by means of a rotatable dial, it will be appreciated that once the basic principle of using such a rack guide formed of a plurality of members is understood, many variations within the scope of the invention will be apparent. So far as the invention is concerned, it is immaterial whether the teeth portion of the rack guide is within or outside the guide groove, or whether the adjustable portion of the rack guide is indexed into operating position by means of a sliding member instead of a rotatable dial, such sliding member being movable longitudinally or transversely of the stationary portion of the rack guide.

Since the feed blade 38 must oscillate as well as move longitudinally during the course of making a buttonhole, in order to aid in maintaining the parts assembled, it will be appreciated that a relatively wide slot 116 must be formed in the base plate 10 which will permit the necessary connection. For this reason at one end, the left end as viewed in Figure 4, of the rack 80 is iixedly disposed a block 118 on the feed blade 38 which serves as the agency for `Supporting a generally U-shaped leaf spring 120 straddling the slot 116 and having its bight anchored directly to the block 118. A threaded stud 122 is carried by the block 118, and, by means of a nut 124 on the stud 122, it will be recognized that the leaf spring 120 is properly anchored so that the legs thereof which straddle the slot 116 bear upon the marginal regions of the base plate which border said slot 116. In this way, the feed blade is retained in sliding engagement against the underside of the base plate 10.

The following portion of the description deals most directly with the production of an oscillatory motion or bite as it is customarily referred to, such motion being necessary in order to produce the proper width of the stitching bordering the buttonhole to be formed. A cam roll 126 is mounted on the shaft 46 for rotation therewith, this being the same shaft rotatably supporting the previously mentioned actuating lever 40. Also carried by the shaft 46 and having fixed connection thereto isa ratchet wheel 128 best seen in Figure 1. Cooperating with the ratchet wheel 128 is a spring-pressed pawl 130 engaging the ratchet wheel so that said ratchet wheel will be rotated by thev actuating lever 40 in a clockwise direction as viewed in Figure l. Formed in the cam roll 126 is a zig-zag groove 132 into which projects an upstanding cam follower 134 carried by a member referred to below. f

Mounted on the forward or left end of the base plate 16 isa swivel lever 136 having a pivotal connection at 137 with said base plate or support 10. The swivel lever 136 is actually composed of a rearwardly extending arm 138 having a longitudinal slot 139 therein for a purpose presently to be described. Integrally connected with the rearwardly extending arm 138 is a laterally extending arm 140 which carries the previously mentioned cam follower 134. A slot 14.1 considerably longer than the slot 139 is disposed in the feed blade 38, this last-mentioned slot being sutiiciently long to permit the feed blade to travel longitudinally far enough to complete the length of the longest desired buttonhole. Still another slot 142 `is provided in the base plate 10, vit being desirably commensurate in length with the slot 139,` but sufficiently wide to permit the maximum degree of "bitef inasmuch as the feed blade must oscillate relative to the base plate. While the feed blade oscillates relative to the base plate 10, nonetheless a pin 144 is necessary in order to transmit oscillatory motion from the swivel lever 136 to the feed blade 38. Accordingly, the pin 144 lits quite snugly in the slots 139 and 141, but not in the slot 142 because` of the need for clearance which will permit lateral movement lof the pin 144 with respect to the base plate 10.

Associated with the swivel lever 136 is an adjusting lever 146 one end 148 of which is pivotally connected to the pin 144 and-the other end of which is prpvided with a series of spaced `teeth 150. The kspaced teeth 150 are cooperable with a stirrup 152 extending laterally from the flange 30 of the kplatform 26, there being a spring 153 maintaining normal engagement between the teeth 150 and the` stirrup 152 through which `the adjusting lever 146 extends. AIntegral with the adjustingv lever 146 is a reversely turned pointer 154.

As lshown in Figures 3 and 4, a cover 156 is provided which conceals and protects most of the moving parts constituting the buttonhole attachment. The lower edge of the cover 156 fits within an upturned angelSS on the base plate or support 10, and on the platform 26 is an upstanding post 160 for the purpose of receiving an anchoring screw 162 which extends through an aperture in the cover 156. In addition to protecting the moving parts of the buttonhole attachment, the cover also serves the function of providing a gauge 164fwith which thepointer 154 coacts to indicate the particular bite which will be produced with a given setting of the pointer 154. IIn the arrangement depicted, since there aresix notches provided at the end of the adjusting lever 146 the gauge markings 164 include a plurality of ` differing length marks 164a, 16411, 164C, 164e', 164e, and 164i, each representing a particular width of stitching obtainable with the disclosed buttonhole attachment.

The longitudinal feed and the oscillatory motion described above is intended to take place only after the sewing machine needle has been fully retracted from the fabric or other material in which the buttonhole is being formed. Accordingly, as best discerned from Figure 1, the cam nose 45 slants upwardly at an acute angle with respect to the general axis of the actuating lever so that the cam 44 will `not engage the follower arm 48 until the sewing machine needle has been completely withdrawn from the fabric. Also, the oscillatory movement is delayed by providing a sufficient clearance of the pawl 130 beforeit engages a tooth on the ratchet 128, the rotation of the ratchet 128 as previously mentioned being instrumental in rotating the cam roll 126.

However, not only is vit necessary to delay the feeding and oscillating of the fabric until the sewing machine needle has been suiciently raised to permit this tohappen Without interference, but it is also exceedingly desirable that a mechanism be employed for intermittently holding the fabric from inadvertent movement with the needle while at the same time not interfering with the movement of the fabric between stitches.` To

this end, a somewhat Z-shaped gripper arm 166, equipped with oppositely directed pintles 168, is rendered pivotal in a vertical plane by virtue of apertures provided in both the standard 14 and the base plate flange 158. Y

In order to transmit motion to the gripper arm 166, there is a connecting link stamped with ears 172 and 174 at each end which form shoulders slightly wider than respective slots provided in the gripper arm 166 and the follower arm flange 58. Biasing the gripper arm so as to maintain engagement between it and the connecting link 170 is a coil spring 176. Consequently, the delay in the movement of the follower, as outlined in the early part of this paragraph, is used in also delaying upward pivotal movement of the Z-shaped gripper arm 166, this being by reason of the upwardly inclined cam nose 45 which prevents the cam 44 from engaging the follower arm 48 until the proper moment. In this connection, it will be appreciated that the actuating lever 4t) is in actual use with the buttonhole attachment connected directly to the sewing machine needle bar, and accordingly the cam'nose 45 is moved in synchronism therewith. Also, it should be pointed out that the particular structural arrangement permits the gripper arm 166 to engage the fabric being stitched once again before the needle enters the fabric and in this fashion serves as a means for steadying and properly orienting the fabric relative to the sewing machine needle. This latter feature comes about from the fact that as soon as the cam nose 45 disengages itself from the follower arm 48, then the gripper arm 166 is permitted to llop downwardly `due to the presence of the spring 52 which acts as a biasing agent for the follower arm 48.

Before using the device, the knob 72 is rotated to such an vextent that the feed blade 38 is moved rearwardly or to the right so that the pinion 76 will reside in the region of the cylindrical post 82, the boss 78 then being within the confines of the U-shaped groove 88. When so moved, thus bringing the pinion 76 to a location opposite that shown in Figure 4, it will be recognized that the dial member 90 may be rotated merely by disengaging the latch upon the particular gauge mark will show clearly that the proper' actuating section 92 has been brought into operative relation, the engagementof the latch S assuring that such relationship will thereafter be maintained as long as the selected arcuate section is to be used in the forming of buttonholes of the selected size.

From an inspection of Figure 5, it can be observed that the presence of the arcuate section 92g, one of the sections which is toothed, in the illustrated position, forms a buttonhole of a size slightly smaller than the maximum possible buttonhole that can be produced with the buttonhole attachment. The maximum-sized buttonhole is obtainable by moving the section 92h and its associated groove 94h into juxtaposition with the groove 88, such a positioning permitting the pinion 76 to follow completcly around the rack 6l) which in the illustrated embodiment is shown integral with the feed blade 38. However proceeding with an operational description rcstrieted to the use of the arcuate section 92g and its associated groove 94g, it will be recognized that when the pinion 76 is disposed so that its boss 78 resides at the bight of the groove 88, then one end of the buttonhole to be formed will be determined.

inasmuch as a relatively large buttonhole is to be formed in the present exemplified situation, the operator may prefer a relatively great width of stitching, and, if that is the case, the user will move the adjusting lever 146 in a rearward direction, that is toward the right as viewed in Figure 2. As shown in this figure, the third from the largest incremental bite is obtained with the setting pictured in Figure 3, such a setting being indicated by the pointer 154 which cooperates with the gauge 164-. Movement of the adjusting lever longitudinally as above outlined causes the pin 144 to be moved longitudinally within the confines of the slots 139 and 141, and, since the throw of the follower arm 136, as will hereinafter be made apparent, is of a constant Value, it can readily be seen that the position of the pin 144 will determine the amount or degree of oscillatory movement produced when the follower arm is moved laterally from one side of the cam groove 132 to the other. This is by reason of the fact that the feed blade 38 pivots about the pinion 76 so that the closer the pin 144 is to the pinion 76, then the more will be the degree of oscillation of the feed blade 38, and its presser foot 36. Owing to the presence of the swivel lever 136, though, it can be seen that compensation is made which will produce a practically linear relationship in the selection of the various bites obtainable with the toothed end 150 of the adjusting lever 146.

Having made the above-mentioned adjustments, which, it should be stressed, may be made before or after mounting of thc attaching means 22 to the presser bar of the sewing machine, the buttonhole attachment is ready for actual use. Accordingly, due to the engagement of the bifurcated end 42 of the actuating lever 4d with the sewing machine needle bar, upward movement of the needle 'oar will cause the actuating lever 40 to be rotated or pivoted relative to the shaft 46 in a clockwise direction, the pawl 130 during the latter portion of the upward movement of the needle engaging one of the teeth on the ratchet 12S to produce a preferred amount of rotary movement of both the ratchet 123 and the roll cam 126 having rotative connection therewith. The preferred amount of rotary movement of the cam 126, due to the upward projection of the follower' 134 into the cam 132, causes the swivel lever 136 to be oscillated in one direction. Gwing to the presence of the pin 144 and its engagement with both the slots 139 and 141, it will be seen that this lateral movement is transmitted to the feed blade 38 and that the feed blade is caused to swing or pivot about the pinion 76. Because of the zig-zag or undulated configuration of the cam groove 132, the next upward stroke of the needle bar will move the swivel lever in an opposite direction.

Concurrently with the rotary movement of the roll cam 126, the nose 45 of the cam 44 abuts against the ange 58 which issues upwardly from the follower arm 48 so that the follower arm is moved in a counterclockwise direction as viewed in Figure 2 to rotate the ratchet 68 a preferred amount. Due to the connection of the ratchet 68 with the pinion 76, it follows that the pinion 76 is also rotated a preferred amount and will move the feed blade forwardly or to the left, it being remembered that the pinion 76 at the outset of this operational explanation has been moved in such a direction by the knob 72 as to bring the pinion 76 at the end of the rack 80 adjacent the cylindrical post 82. In this way, the pinion 76 is started in a direction toward the position shown in Figure 4 which position is nearest the rear of the buttonhole attachment. Of course, the engagement of the boss 78 in the grooves 88 and 94g tracks the pinion 76 along one side of the rack 80 and in this way one side of the buttonhole is completely stitched. It might be mentioned at this point that due to the alignment of the groove 94g with the groove 88 there is imposed no restriction upon the passage of the boss 78 from the groove 88 to the grooved section 94g. When the boss 78 reaches the bight of the grooved section 94g, then the pinion 76 is caused to be moved to the other side of the groove 94g, the pinion 76 engaging the teeth 92g during this transfer from one side to the other. Once having been moved to the other side of the groove 94g, then the pinion progresses along the opposite side of the rack 80, being in mesh with the teeth constituting this opposite side of said rack. Thereafter the boss 78 will re-enter the groove 83, and, when the boss reaches the bight of this groove, then the buttonhole will have been completed as far as stitching is concerned and is ready for slitting.

All the time that the reciprocation of the sewing machine needle bar has been moving the actuating lever upwardly and downwardly to cause repeated engagement of the cam nose 45 with the upstanding ange 58 on the follower arm 48, the pawl has been causing incremental degrees of rotation of the cam roll 126 which by reason of the zig-zag groove 132 causes the follower 134 to be moved laterally back and forth in such a manner that the width of the stitching will be maintained constant. Thus, from the foregoing description, it will be recognized that longitudinal movement of the feed blade 38 and its presser foot 36 is produced by the rotation of the pinion 76 and its ratchet and that the oscillatory movement is produced by the sidewise movement of the follower 134 produced by the cam roll 126 and its ratchet.

Also, the rotation of the pinion 76 which is caused by the pivoting of the follower arm 48 by the cam 44 results in the pivoting of the gripper arm 166 to release thereby the fabric or other material being stitched at the proper time for the foregoing longitudinal and shifting movements thereof. The gripper arm 166, it will be recognized, is synchronized in its particular movements with the actuating lever 40 by virtue of the inclined nose 45 on the cam 44. Thus, there can be no interference from the gripper arm 166, and it will be always moved in proper respect to the feeding of the fabric.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the language used in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

I claim:

1. A buttonhole attachment for sewing machines corn.- prising a bottom supporting plate, a feed blade provided with a set of teeth disposed in a substantially U-shaped pattern in xed relation therewith for determining one end of a buttonhole to be formed, means connecting said blade to the underside of the supporting plate'for oscillating: and sliding movement, a member shiftably mounted on the underside of said feed bladehaving in its upper surfacea plurality of sets of teeth each disposed in a substantially U-shaped pattern registrable selectively with said first set of teeth for determining the other end of the buttonhole, said member having v a portion extending laterally beyond the edge of the blade-and supporting plate to permit manual adjustment of said member, a pinion rotatably carried by said support successively engageable with both sets of teeth, and means for rotating `said pinion to slide said feedblade relative to said support.

2. A buttonhole attachment for sewing machines comprising a support, a feed blade provided witha set of teeth disposed in a buttonhole pattern and means forming a groove contoured to correspond in outline to one end of said pattern of said set of teeth in order` to determine one end of a buttonhole to be formed, means connecting said blade to the support for oscillating and sliding movement, a member slidably movable with respect to said feed blade having a groove constructed to correspond in outline to the other end of said pattern of said set of teeth and movable into registry therewith to form a. buttonhole track of maximum length, and means on said member forming a second set of teeth disposed inI a substantially U-shaped pattern and a groove contouredto correspond in outline to the pattern of said second set of teeth in order to determine the other end of a smaller buttonhole, said second set of teeth and its associated groove being registrable with the teeth and groove of the feed blade to form a buttonhole track of smaller lengthga pinion rotatably carried by said support engageable with the teeth `of either buttonhole track and having a bossrguided by said grooves, and means for rotating said pinion to slide said feed blade relative to said support.

3.Y A buttonhole attachmentfor sewing machines comprising a support, a feed blade equipped with a rack dimensioned for the maximum desired length of buttonhole, means connecting said blade to the support for oscillating and sliding movement, a pinion rotatably carried by said support in mesh with said rack, meansfor rotating said pinion to slide said feed blade relative to said support, and a rotatable dial member carried `by said blade, said dial member beingprovided with a plurality of angularly arranged rack sections at various radial distances, whereby the effective rack length may be modied by rotating said dial member to bringany selected rack section into registry with said rack to form a buttonhole less than said maximum length.

4. A buttonhole attachment for sewing machines comprising a support, a feed -blade provided with an elongated slot equipped with gear teeth distributed about the edge thereof to form a rack, the rack being vdimensioned for the maximum desired length of buttonhole, means yconnecting said blade to the support for oscillating and sliding movement, a pinion rotatably carried by said support in mesh with said rack and having an axially extending boss, means for rotating said pinion to` lslide said feed blade relative to said support, atcylindrica'l post aixed to said blade having a U-shaped groove for receiving said boss to guide said pinion from one sideof the rack to the other at the closed end of saidgroove and a rotatable dial member encircling said post provided with a plurality of angularly arranged U-shapedv groovesA of various lengths registrable radially with said first mentioned U-shaped groove, one of said last mentioned U-shaped grooves beingof a length to guide said pinion about the entire length of said rack to form said maximum desired length of buttonhole and the other U-shaped grooves being of lesser length to form buttonholes less than said maximum length, said .dial member having an arcuate section of teeth spaced near the closed en-d of each last mentioned groove with the exception of the longest 'so that said pinion will bev moved fromr one side of the rack to the other side at the closed ends of said last mentioned grooves.

5. A buttonhole attachment for sewing machines comprising a support, a feed blade provided with rack means for determining one end of a buttonhole to be formed, means connecting said blade to the support for oscillating and sliding movement, a circular' dial member pivotally attached to the underside of said blade having-a plurality of angularly arranged respective rack means disposed at various radial distances for selectively determining the locus of the other end of the buttonhole, the portion of said feed blade overlying said dial member being generaliy coextensive therewith but notched at one location to expose to view a segment of said dial member, indicia i distributed at 'spaced points on said dial member for indicaring in the region of said not-ch the particular rack means on said dial member which is in registry with said first mentioned rack means, a pinion rotatably carried by said support successively engagea'ble with said first rack means and the particular rack means on the dial member in registry therewith, and means for rotating said pinion to slide said feed blade relative to said support.

6. A buttonhole attachment for sewing machines comprising a bottom supporting plate, a feed blade provided with rack means for determining one end of a button-hole to be formed, means connecting said blade to the underside of the supporting plate for oscillating and sliding movement, a circular dial member pivotally attached to the underside of the blade having a plurality of angularly arranged individual rack means disposed at various radial distances for selectively determining the locus of `the other end of the buttonhole, said dial memberV having a portion extending beyond the edge of said supporting plate and the edge of said blade to permit manual adjustment of said member and having indicia on its upper face corresponding to the individual rack means, said dial Y member having a plurality of radial notches, one for each individual rack means, a latch mounted on the underside of said feed blade engageable with any one of said notches when the individual rack means associated therewith is in registry with said first rack means to prevent undesired .rotation of said dial member, said latch having `an actuating member extending beyond the edge of the blade, a pinion rotatably carried by said supporting plate successively engageable with said first rack means and the particular rack means on the dial member in registry therewith, and means for rotating said pinion to slid saidfeed blade relative to said supporting plate.

7. A buttonhole attachment for sewing machines cornprising a support, a feed blade mounted on said support for sliding and oscillating movement, a rotatable pinion mounted on the support, a track guide on one end of the feed blade engaging said pinion, an actuating arm pivotally connected to the support and extending rearwardly therefrom for pivoting movement transversely of the blade, means adjustable toward and away from the pivot of the arm forming a connection between the arm and the feed blade intermediate the ends of the feed blade,

said blade being movable longitudinally relative to the actuating arm, means for intermittently moving the actuating arm transversely of the feed blade, and means for rotating the pinion.

8. A buttonhole attachment for sewing machines com prising a support, a feed blade mounted on said supporti for longitudinal sliding and transverse oscillating movement, a rotatable pinion mounted on the support, a track guide on one end of the feed blade engaging said pinion, an yactuating arm mounted on the support for oscillating movement transversely of the feed blade, means adjustable longitudinally of the support interconnecting the actuating arm and the feed blade intermediate the ends of the feed blade permitting longitudinal movement of the feed blade relative to the actuating arm, a rotatable cam foreoscillating the actuating arm, and means for intermittently rotating the cam and the pinion.

9. A buttonhole attachment for sewing machines comprising a support adapted to be attached to the presser bar of the sewing machine with a portion thereof adjacent the needle, a feed blade having a longitudinal slot, a swivel lever pivotally mounted ou the portion of said support adjacent the needle and having a longitudinal slot, selectively positionable connecting means extending through said slots, means about which the feed blade may fulcrum for moving the blade longitudinally and means for rocking said swivel lever to impart oscillating movement to said feed blade via said connecting means.

l0. A buttonhole `attachment for sewing machines comprising a support, a feed blade having a longitudinal slot, a swivel lever pivotally mounted on said support having a longitudinal slot, an adjusting lever pivotally retained at one end by said support, pin means extending through the other end of said adjusting lever and said slots, means about which the feed blade may fulcrum for moving the blade longitudinally and means for rocking said swivel lever to impart oscillating movement to said feed blade via said pin means.

ll. A buttonhole attachment for sewing machines comprising a support, a feed blade having a longitudinal slot, a swivel lever pivotally mounted at the forward end of said support provided with a rearwardly extending arm having a longitudinal slot therein, an adjusting lever having its rear end pivotally retained at any one of a number of selective points near the rear end of said support, a pin extending through the forward end of said adjusting lever and said slots, gear means about which the feed blade may fulcrum for moving the blade longitudinally, and means for rocking said swivel lever through a limited arc to impart oscillating movement to said feed blade by means of said pin.

l2. A buttonhole attachment for a sewing machine equipped with a needle bar comprising a support, a feed blade having a rack and a longitudinal slot, a swivel lever pivotally mounted at the forward end of said support including a rearwardly extending arm and a lateral arm integral therewith, the rearwardly extending arm having a longitudinal slot therein and the lateral arm carrying an upstanding cam follower thereon, an adjusting lever having its rear end pivotally retained at any one of a number of selective points near the rear end of said support, a pin extending through the forward end of said adjusting lever and said slots, a pair of upstanding spaced standards on said support, a transverse pin journaled by said standards, a cam roll having a zig-zag groove disposed about its circumference into which said cam follower projects to transmit rocking movement to said swivel lever when said cam is rotated, an actuating lever rotatably carried by said transverse pin adapted to engage the needle bar of the sewing machine, a ratchet iixedly carried by said transverse pin for rotation therewith, a pawl on said actuating lever engageable with said ratchet for rotating said cam a prescribed amount each time said needle bar is moved upwardly, a rotatable pinion carried by said support in mesh with said rack for moving said feed blade longitudinally while serving as a fulcrurn therefor, and means associated with said actuating lever for rotating said pinion.

13. A buttonhole attachment for a sewing machine equipped with a needle bar and a needle carried thereby comprising a support, a feed blade mounted on the support for sliding and oscillating movement having a longitudinal slot intermediate its ends, a swivel lever pivotally mounted at the forward end of said support including a rearwardly extending arm and a lateral arm integral therewith, the rearwardly extending arm having a longitudinal slot therein registering with the slot in the feed blade and the lateral arm carrying an upstanding arm follower thereon, an adjusting lever having its rear end pivotally retained at any one of a number of selective points near the rear end of said support, a pin extending through the forward end of said adjusting lever and said slots, a pair of upstanding spaced standards on said support, a transverse pin journaled by said standards, a cam roll having a zig-Zag groove disposed about its circumference into which said cam follower projects to transmit rocking movement to said swivel lever when said cam is rotated, an actuating lever rotatably carried by said transverse pin for rotation therewith, a pawl on said actuating lever engageable with said ratchet for rotating said cam a prescribed amount each time said needle bar is moved upwardly, a pivotal follower arm, said actuating lever being provided with a cam for engaging said follower arm, a pawl on said follower arm, a ratchet rotatably mounted on the support and engageable by said pawl to cause intermittent rotation thereof when said follower arm is moved by said cam, a pinion rotatable with said last mentioned ratchet, and a rack guide of variable length carried by said feed blade engaging the pinion.

14. A buttonhole attachment for a sewing machine equipped with a needle bar and a needle carried thereby comprising a support, a feed blade having a longitudinal slot and a rack dimensioned for a desired maximum length of buttonhole, a swivel lever pivotally mounted at the forward end of said support including a rearwardly extending arm and a lateral arm integral therewith, the rearwardly extending arm having a longitudinal slot therein and the lateral arm carrying an opstanding arm follower thereon, an adjusting lever having its rear end pivotally retained at any one of a number of selective points near the rear end of said support, a pin extending through the forward end of said adjusting lever and said slots, a pair of upstanding spaced standards on said support, a transverse pin journaled by said standards, a cam roll having a zig-Zag groove disposed about its circumference into which said cam follower projects to transmit rocking movement to said swivel lever when said cam is rotated, an actuating lever rotatably carried by said transverse pin for rotation therewith, a pawl on said actuating lever engageable with said ratchet for rotating said cam a prescribed amount each time said needle bar is moved upwardly, a pivotal follower arm, said actuating lever being provided with a cam for engaging said follower arm, a pawl on said follower arm, a ratchet rotatably mounted on the support and engageable by said pawl to cause intermittent rotation thereof when said follower arm is moved by said cam, a pinion rotatable with said last mentioned ratchet equipped with a cylindrical boss, a downwardly depending cylindrical post secured to the underside of the feed blade, aportion of said cylindrical post underlying one end of said feed blade rack which underlying portion is provided with a U-shaped groove for guiding said pinion boss, and a manually rotatable dial eircumposed about said cylindrical post having a plurality of angularly arranged arcuate rack sections disposed at various radial distances for modifying the effective length of said feed blade rack and a U-shaped groove section associated with each arcuate rack section for guiding said pinion boss, said arcuate rack sections and the groove sections associated therewith being selectively registrable with said rack on the feed blade and the groove in said post.

15. A buttonhole attachment for a sewing machine equipped with a needle bar and a needle carried thereby comprising a support, a feed blade having a longitudinal slot and a rack dimensioned for a desired maximum length of buttonhole, a swivel lever pivotally mounted at the forward end of said support including a rearwardly extending arm and a lateral arm integral therewith, the rearwardly extending arm having a longitudinal slot therein and the lateral arm carrying an upstanding arm follower thereon, an adjusting lever having its rear end pivotally retained at any one of a number of selective points near the rear end of said support, a pin extending through the forward end of said adjusting lever and said Slots, a pair of upstanding spaced standards on said support, a transverse pin journaled by said standards, a cam roll having a zig-zig groove disposed about its circumference into which said carnfollower projects to transmit rocking movement to said swivel lever when said cam is rotated, an actuating lever rotatably carried by said transverse pin for rotation therewith, a pawl on said actuating lever engageable with said ratchet for rotating said cam a prescribed amount each time said needle bar is moved upwardly, a pivotal follower arm, said actuating lever being provided with a cam for engaging said follower arm, a pawl on said follower arm, a ratchet rotatably mounted on the support and engageable by said pawl to cause intermittent rotation thereof when said fol` lower arm is moved by said cam, a pinion rotatable with said last mentioned ratchet equipped with a cylindrical. boss, a downwardly depending cylindrical post secured to the underside of the feed blade, a portion of said cylindrical post underlying one end of said feed blade rack which underlying portion is provided with a U-shaped groove for guiding said pinion boss, a pivotal gripper arm carried by said support adapted to engage the material to be stitched, and means connecting said gripper arm with said follower arm so that said gripper arm will be operated in a synchronized manner with said actuating lever.

References Cited in the tile of this patent UNITED STATES PATENTS 318,471 Harris May 26, 1885 442,695 Powell Dec. 16, 1890 467,643 Powell Jan. 26, 1892 1,802,551 Bohmann et al. Apr. 28, 1931 2,547,977 Russell Apr. 10, 1951 2,619,925 Sharenow Dec. 2, 1952 FOREIGN PATENTS 7,496 Great Britain 1888

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