US2168741A - Blind stitch sewing machine - Google Patents

Description

3, 1939- c. w. MUELLER BLIND STITCH SEWING MACHINE Filed July 26, 1937 8 Sheets-Sheet 1 Char/es W Mae/Aer Aug. 8, 1939. c. w. MUELLER BLIND STITCH SEWING MACHINE Filed July 26, 1937 8 Sheets-Sheet 2 Char/es W Mae/Aer v GUM-M41 g- 1939- c. w. MUELLER v 2,168,741 BLIND STITCH SEWING MACHINE Filed July 26, 19:57 s Sheets-Sheet 5 Fig. 5.

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Aug. 8, 1939; c. w. MUELLER BLIND STITCH SEWING MACHINE Filed July 26, 1957 8 Sheets-Sheet 8 Ch qr/es W Mue/Aer Patented Aug. 8, 1939 UNITED STATES BLIND STITCH SEWING MACHINE Charles W. Mueller, St. Louis, Mo., assignor to Lewis Invisible -Stitch Machine Company, St. Louis, Mo., a corporation of Maine Application July 26, 1937, Serial No. 155,788

12 Claims. 7 (Cl. 1121'76) Ihis invention relates to new and useful improvements in sewing machines generally, although more particularly to sewing machines of the blind stitch type.

In blind stitch sewing machines, such as is shown in each of my prior Patents 1,989,602, Jan. 29, 1935 and 2,018,186, Oct. 22, 1935, the reciprocatory ridge forming element is mounted directly below the needle on a work support which is fiulcrumed on a horizontal pivot located in rear of the needle path. The ridge forming element which in one form is a disc, is provided with relatively low and high peripheral portions which are alternately positioned in cooperative relation with the needle to form resultant anchor and skip stitches. The driving connections between the main shaft and the oscillatory shaft which is journaled on the work support and which reciprocates the ridge forming element, is such that when a seam or extremely thick layers of fabrics are fed over the element, the work support will be depressed'and the driving connections will cause the oscillatory shaft to rock and thereby shift the ridge forming element out of its true cooperative relation with the needle with the result that one or more stitches will be improperly positioned in the fabric or fabrics.

One of the important objects of this invention is to provide driving connections between the main shaft and the reciprocatory ridge forming element operating shaft whereby the element will remain in its true cooperative relation with the needle when the pivoted work support is depressed and thereby insure the proper positioning of the stitches in the fabric or fabrics.

' Another object of the invention is to provide a main frame which includes a standard, a laterally extending upper arm and a forwardly and downwardly inclined arm, a reciprocatory needle and a presser foot mounted on the front end of the forwardly extending arm, and a work support which is fulcrumed on a horizontal pivot'located in rear of the needle path, whereby the presser foot will remain at the same height relative to the operator and yet afford increased room under the laterally extending arm for the passage of the work when the work is being fed rearwardly' and also when the work is being removed from the machine upon depression of the pivoted work support.

Another object of the invention is to provid manually releasable means for normally locking the work support against abnormal depression to thereby insure proper feed action of the fabrics, yet permitting a slight depression of the work support to permit not only a variation in the thicknesses of the fabrics being stitched, but also to permit seams being fed over the ridge forming element.

A further object of the invention is to provide manually operable means for varying the initial position of the work support and the ridge forming element which is mounted thereon, relative to the needle in order to set the machine for a predetermined depth of needle penetration in the fabric or fabrics.

With these and other objects in view which will more fully appear, the nature of the invention will be more clearly understood by following the description, the appended claims, and the several views illustrated in the accompanying drawings.

In the drawingsz- Figure 1 is a top plan view of a machine constructed in accordance with my invention,

Figure 2 is a right hand elevation thereof, the standard being shown in section,

Figure 3 is a front elevation thereof,

Figure 4 is a left end elevation thereof,

Figure 5 is a bottom plan View of the machine,

Figurefi is an enlarged vertical section taken on the line 6-6 of Figure 1, the stitching mechanism being omitted,

Figure 7 is an enlarged detail section showing a slight depression of the work support relative to the needle, I

Figure 8 is an enlarged vertical section showing the work support in its locked or normal position,

Figure 9 is a similar View but showing the work support in its unlocked or fully depressed position,

Figure 10 is a view showing the driving connections between the main shaft and the oscillatory shaft which operates the ridge forming element, the view indicating the limits of the oscillatory movements of the element when forming all anchor stitches,

Figure 10 is a view showing the corresponding position of the control lever,

Figure 11 is a view similar to Figure 10 but showing the limits of oscillatory movements of the element when forming alternate "anchor and skip stitches. I

Figure 11 is a View showing the corresponding position of the control lever,

Figure 12 is a plan View of the presser foot and showing the needle, the top feed dog, the ridge forming element, and the work clamp, and

Figure 13 is a top plan view of the left end of the work support showing the ridge forming element,

the operating shaft therefor, and the work clamp.

Like reference numerals designate corresponding parts throughout the several figures of the drawings.

The sewing machine includes a main frame A which comprises a base 5, a standard 6, an arm 'I which extends laterally from the upper end of the standard and terminates in a forwardly extending arm 8 which is inclined downwardly and forwardly-relative to the base, and posts 9, 9 which are integral with the base and are located at the right of the arm 8 but in rear of the forward end thereof.

Rigidly fixed to the forward or free end of the arm 8, is a presser foot B having a centrally located longitudinal opening or slot Ill formed therein, the foot being forwardly and downwardly inclined in a plane disposed in parallelism to the major axis of said arm 8.

Journaled in the upper end of the standard 6 and in the arm I is a main shaft II, and journaled in the arm 8 and extending longitudinally thereof is an oscillatory needle shaft I2 having a needle arm I3 fixed to its front end. The needle shaft I2 is located directly above the presser foot opening ID and has its longitudinal axis in a downwardly and forwardly inclined plane dis,- posed in parallelism with the presser foot. Attached to the needle arm I3 is a curved needle I4 which reciprocates across the opening I of the foot. The needle shaft I2 is oscillated from the main shaft II by connections such as is shown in my prior Patent 2,018,186 referred to above. A looper or spreader I5 cooperates with the needle I4 in the usual manner to form single thread chain stitches, although any other type of complemental stitch forming mechanism may be employed if desired. The looper I5 is fixed to a looper rod I6 which is fulcrumed on a depending arm I! pivoted on a horizontal pin I8 mounted in the arm 8 and the looper rod is driven from the main shaft II by the usual connections.

A work support C is pivoted by bearings I9 to the ends of a horizontal shaft clamped in spaced bearings 2|, 2| formed in the posts 9, 9 of the main frame. It will be noted that the pivot shaft 20 is disposed in a plane parallel to the main shaft II and that said pivot shaft is located considerably in rear of the needle I4 as well as in rear of the front end of the presser foot B. This work support C has its left end reduced to form a horn 22 and projecting laterally from the outer end of the horn is a rectangular frame 23 having an open top and bottom. This frame 23 is located directly under the presser foot B and includes front and rear walls 24,25 and an end wall 26.

Operating in the presser foot opening I0 for intermittently projecting a node of fabric upwardly into needle penetrating position, is a ridge forming element Dwhich in this instance consists of a disc fixed to an operating shaft 21 which is journaledat the ends in screw bearings 28, 29, the screw bearing 28 being mounted in an opening 30 formed in the end wall 26 of the frame 23 and th screw bearing 29 being mounted in an opening 3| formed in a lug 32 which depends from the under side of the work support C. The oscillatory operating shaft 2'! is disposed in a horizontal plane in parallelism not only with the main shaft II but also with the pivot shaft 20 of the work support. It will, therefore, be seen that the work support C extends forwardly from the pivot shaft 20 to a point under the presser foot B and that this work support is capable of swinging downwardly away from the presser foot or upwardly toward the same. It will also be observed that the shaft 21 which operates the ridge forming element D is disposed in front of the pivot shaft 2!] and is movable upwardly and downwardly with the work support and consequently when the work support is lowered the ridge forming element D will be correspondingly lowered with respect to the path of the needle. The ridge-forming disc D is formed with a concentric periphery 33 and with a radial front edge 34, and a recess 35 is formed at their juncture, the recess forming a resultant step 36. It will be observed that the concentric edge 33 and the step 36 form peripheral surfaces or portions of different radii which are arranged in tandem, the portion 33 constituting a high portion and the step 36 constituting a low portion. When the high portion 33 is positioned under the needle the latter will form resultant anchor stitches in the fabric or fabrics and when the low portion 36 is positioned below the needle, the latter will form skip stitches in the fabric or fabrics. In other words, the effective depth of needle penetration in the fabric or fabrics is constant when the high portion 33 is positioned below the needle but when the low portion 36 is positioned below the needle the depth of needle penetration will be decreased, as fully explained in my prior Patent 2,018,186 referred to above.

An upwardly spring pressed work clamp E is mounted on the work support C for alternate cooperation with the presser foot B and a -motion top feed dog F. The top feed dog F operates in the opening It of the presser foot B and is supported on the frame arm 8 and is operatively connected to themain shaft I I in the usual manner. This feed dog operates in rear of the needle path and cooperates with the work clamp E to intermittently feed the fabric rearwardly when the needle is out of said fabric. The work clamp E cooperates with the bottom of the foot B to clamp the fabric therebetween during the idle motions of the feed dog F whereby said fabric will be held against the thrust of the needle.

The work support C is capable normally of a small free upward and downward movement about its pivot 20 to permit not only a variation in the thicknesses of materials being stitched but also to permit seams being fed over the ridge forming disc D. To this end, the work support C is provided with depending integral front and rear walls 3?, 38 respectively arranged on opposite sides of the disc operating shaft 21. A head 39 includes an attaching plate 40 and a depending tubular neck 4I having an open lower end. The head 39 is rigidly attached to the lower edges of the depending walls 31, 38 by screws 42, 42. Mounted in said neck for vertical movements relative thereto is a core or support 43. A limiting screw 44 passes downwardly through a non-threaded opening 45 formed in the plate 43, the lower end of the screw being threaded into the core 53 and the head 45 of said screw cooperating with the plate 40 to limit the upward movement of the work support C relative to the core or support 43. The upper surface of the core is normally spaced below the plate 40 and the upper portion of the core is reduced to form a resultant peripheral recess for receiving a coil spring 4'! which engages the bottom wall of the recess and the plate 40 and functions to yieldably retain the work support C against downward movement relative to said core.

The core 43 is normally locked against vertical movements, but when the core is moved vertically the work support C, the disc D, ,and the work clamp E are moved with it. The lower end of the core 43 is provided with a depending lug 48. -A

toggle is connected to the lug 48 and to the base 5 of the main frame. The toggle includes a bell crank lever 49 which includes an arm 50. normally disposed in a generally vertical position; and a forwardly extending generally horizontal arm 5 I. Thelower end of the arm 50 is 'fulcrumed on an eccentric 52 which is fixed to a horizontal shaft 53, the latter being supported in thebase 5 as shown in Figures' l, 6 and 8. The ends of the shaft 53 are journaled in the base 5 below the upper sur- 'face' thereof. A normally vertically disposed link 54 is pivotally connected at its upper end by a pin 55 to the lug 48 and at its lower end by a pin 55 to the upper end of the toggle arm 50, the pin 56 being rigidly secured to the link 54-by a set screw '51. A coil spring 58 is disposed around the projecting end of the pin 56, one end of the spring being anchored in atransverse slot 59 formed in the outer end of the pin and the other end of the spring engaging under a stop pin 60 fixed to the bell crank 49. The spring 58 functions to yieldably retain the toggle elements 50, 54 in their extended or locked positions as shown in Figure 8, and a stopshoulder 6| fixed to the arm 50 cooperates with the stop shoulder 62 on the bottom of the link 54 to prevent the toggle elements passing beyond their locked positions. It will be noted'that the arm 50 and the link 54, when in their normal or locked positions, are in general longitudinal alinement, i. e., the pivots 55, 56 and 53 are in alinement in a plane which is slightly inclined to the vertical, or in other words, in a plane at right angles to the plane of the,

foot B, A chain 63 which is adapted 'to be connected to. a treadle or knee-press; has its upper end connected to the forward end of the arm 5| of said bell crank lever. Thus upon operation of theknee-press or treadle the toggle will be broken and the support or core 43 together with the work support C and parts mounted thereon, will be depressed to permit the ready insertion or withdrawal of the material, and-upon, release D, and thereby set the machine for materials of difierentthicknesses, I have provided a hand adof the standard 6.

justin-g shaft 64 which is journaled in a bushing 65 mountedin a tubular bearing bracket 66 secured in an opening formed in the front wall a A finger knob 67 is rigidly attached to the front end of the shaft 64 and a spring pressed pin 68 cooperates with the knob to retain the shaft in' any position of adjustment. Journaled on the bracket 66 is a worm wheel 69 which is in constant mesh with aworm I0 formedv on the inner end of the shaft 64. J ournaled in the base 5 is a horizontal rock shaft I! having a rock arm I2 fixed to its right hand end, said arm being pivotally connected by a link I3 to the worm wheel 69. The other end of the rock shaft H is provided with a rock arm I4 which is pivotally connected to the rear end of a rack bar 15 which extends forwardly along the base to a point below and in front of the eccentric carrying shaft 53. The rack bar I5 is provided along its upper forward edge with rack teeth I6 which engage the teeth of a pinion I'I fix'ed on said shaft 53. A disc I8 is journaled on the shaft 53 and is provided with a pin I9 forming a support for the front end of said rack bar. A coil spring is connected at one end to the disc I8 and at its other end to the base 5 and functions to urge the pin I9 upwardly whereby the rack bar will be retained yieldably in engagement with the pinion 'I'I. It will, therefore, be seen that when the knob 61 is rotated the'rack bar 15 will be moved endwise, the shaft 53 together with the eccentric 52 will be rotated, and the work support will be raised or lowered, depending on the direction of rotation of the knob. I

The ridge formingelement D is reciprocated from the main shaftl I 7 by a train of mechanism including a manuallycontrol lever whereby either the high or low portions 33, 36 of the'disc or element will be alternately presented to the needle to thereby form alternate anchor and skip stitches in the material or whereby the high portion 33 only of the disc or element will be succes sively presented to the needle to thereby form successive anchor stitches in the material. To this end, a bell crank lever BI is journaled on a horizontal axis 82 in the standard 6 and below the main shaft H. The bell crank lever 8| includes a forwardly extending horizontal arm 83 which is connected by a link 85 to the main shaft II through the medium of a 2-to-1 reduction gear coupling which is indicated as a whole by the numeral 86 and which is fully shown and described in my prior Patent 1,989,602 referred to above. Thebell crank lever 8i includes a depending arm 8 l*w'h'ich' is pivotally connected as at 88to the rear end of a forwardly extending link 88. A horiz'ontal'shaft Bfl'is journaled in a base lug or post 9| at a point between the pivot shaft 20 of the work'support C and the disc operatingshaft 21, said shaft 90 being disposed in parallelism with said shafts 2B and 21, Fixed to the left hand end of the shaft is an eccentric pin 92 and alever 93 is journaled intermediate its ends on'said eccentric pin. The lower arm 94 of said lever is pivotally connected as at 95 to the forward end of the link 89 and the upper arm 96 of said lever is pivotally connected as at 91 to a rearWa-rdly extending link 98 which is pivotally connected at its rear end as at 99 to a depending rock arm' I 00 clamped to the disc operating shaft 21; Fixed to the left hand end of the eccentric shaft 98 is an upwardly extending rock arm Illl and pivotally connected to the upper end of said arm as at I52 is a rearwardly extending link I03, the rear end of said link being pivotally connected as'at I04 to the lower end of a manually operable control lever Ill5which'is fulcrumed on the disc operating shaft 2'! and has itsup'per end provided with a finger-piece or knob 106 which projects through an opening IEJ'I formed in the work support C. The knob I66 also projects upwardly through a slot IE8 formed in a plate 109 mounted on the upper surface of the work support C.

It will be noted that the eccentric pin 92 constitutes a shiftable fulcrum for the lever 93 and that when the shaft 55 is oscillated by the manually control lever I95 said fulcrum will be shifted either forwardly or rearwardly and the disc operating shaft 21 will be angularly shifted thereby, and consequently the disc D will be shifted angularly with respect to the needle path; The driving connections between the main shaft II and the disc operating shaft 21 are such that the disc D will partake of a greater angular movement during alternate rearward strokes thereof and a lesser angular movement during intermediate rearward strokes. Thus when the manually control lever N15 is in the position shown in Figure 10 the high peripheral portion 33 of the disc D will be presented to the needle during successive rearward movements of the disc whereby successive anchor stitches Will be formed in the fabric; and when. the control lever is in the position shown in Figure 11 the high and low peripheral portions 33, 36 will be alternately presented to the needle whereby alternate anchor and skip" stitches will be formed in the fabric. It will furthermore be observed that when the work support C is in its normal or locked position said support is capable of having a slight downward movement due to the intermediate spring 41, and that by reason of the lever 93 being disposed between the pivot shaft 20 of the work support and the disc operating lever 21 together with the link 98 which connects the lever 93 with the rock arm Hi8, this slight downward movement of the work support will maintain thelow peripheral portion 35 of the disc D in proper cooperative relation to the needle path whenever said low portion 36 is positioned in cooperative relation with the needle and consequently the stitches will be properly positioned in the fabric.

It is of course to be understood that the details of structure and arrangement of parts may be variously changed and modified without departing from the spirit and scope of my invention.

I claim:

1. In a blind stitch sewing machine, the combination with a main frame including a base and a forwardly extending arm disposed in a plane above the base, of a main shaft journaled in the frame, a presser foot fixed to the front end of the arm and provided with an opening, a stitch forming mechanism mounted on the arm and including a needle mounted for reciprocations above the foot and across the opening therein, a work support mounted on the base to swing upwardly and downwardly relative to the foot and about a horizontal axis located in rear of the needle, means for normally retaining the work support yieldably against depression, a reciprocatory ridge forming element operating in the presser foot opening for projecting a ridge of fabric upwardly into needle penetrating position and movable upwardly and downwardly with said work support, an oscillatory shaft journaled on the work support and disposed in parallelism with the axis thereof and operatively connected to said element, and driving connections between the main and oscillatory shafts for operating the latter and including devices for retaining the oscillatory shaft against angular movement upon depression of the work support.

2. In a blind stitch sewing machine, the combination with a main frame including a base and a forwardly extending arm disposed in a plane above the base, of a main shaft journaled in the frame, a presser foot fixed to the front end of the arm and provided with an opening, a stitch forming mechanism mounted on the arm and including a needle mounted for reciprocations above the foot and across the opening therein, a work support mounted on the base to swing upwardly and downwardly relative to the foot and abouta horizontal axis located in rear of the needle, means for normally retaining the work support yieldably against depression, an oscillatory ridge forming disc operating in the presser foot opening for projecting a ridge of fabric upwardly into needle penetrating position and movable upwardly and downwardly with said work support, an oscillatory shaft journaled on the work support and disposed in parallelism with the axis thereof and rigidly connected to said disc, and driving connections between the main and oscillatory shafts for operating the latterand including devices for retaining the oscillatory shaft against angular movement upon depression of the work support.

3. In a blind stitch sewing machine, the combination with a-main frame including a base and a forwardly extending arm disposed in a plane above the base, of a main shaft journaled in the frame, a presser foot fixed to the front end of the arm and provided with an opening, a stitch forming mechanism mounted on the arm and including a needle mounted for reciprocations' above the foot and across the opening therein, a work support mounted on the base to swing upwardly and downwardly relative to the foot and about a horizontal axis located in rear of the needle, means for normally retaining the work support yieldably against depression, an oscillatory ridge forming disc operating in the presser foot opening for projecting a ridge of fabric upwardly into needle penetrating position and movable upwardly and downwardly with said work support, said disc having high and low peripheral work presenting portions arranged in and a forwardly extending arm disposed in a plane above the base, of a main shaft journaled in the frame, a presser'foot fixed to the front end of the arm and provided with 'an opening, a stitch forming mechanism mounted on the arm and including a needle mounted for reciprocar;

tions above the foot and across the opening therein, a work support mounted on the base to swing upwardly and downwardly relative to the foot and about a horizontal axis located in rear of the needle, means for normally retaining the Work support yieldably against depression, a reciprocatory ridge forming element operating in the presser foot opening for projecting a ridge of fabric upwardly'into needle penetrating position and movable upwardly and downwardly with said work support, an oscillatory shaft journaled on the work support and disposed in parallelism with the axis thereof and operatively connected to said element, and driving connections between the main and oscillatory shafts for operating the latter and including devices for retaining the oscillatory shaft against angular movement upon depression of the work support, said devices including a lever fulcrumed on an axis located intermediate the work support pivot and the oscillatory 'shaft, a rock arm fixed to the oscillatory shaft, and a link connecting the lever and the rock arm.

5. In a blind stitch sewing machine, the combination with a main frame includinga base and a forwardly extending arm disposed in a plane above the base, of a main shaft journaled in the frame, a presser foot fixed to the front end of the arm and provided with an opening, a stitch forming mechanism mounted on the arm and includinga-needle mounted for reciprocations above the foot and across the opening therein, a work support mounted on the base to swing upwardly and downwardly relative to the foot and about a horizontal axis located in rear of the needle, means for normally retaining the work support yieldably against depression, an oscillatory ridge forming disc operating in the presser foot opening for projecting a ridge of fabric upwardly into needle penetrating position and movable upwardly and downwardly with said work support, an oscillatory shaft journaled on the work support and disposed in parallelism with the axis thereof and rigidly connected to said disc, and driving connections between the main and oscillatory shafts for operating the latter and including devices for retaining the oscillatory shaft against angular movement upon depression of the work support, said devices including a lever fulcrumed on an axis located intermediate the work support pivot and the oscillatoryshaft, a rock arm fixed to the oscillatory shaft, and a link connecting the lever and the rock arm.

6. In a blind stitch sewing machine, the combination with a main frame including a base and a forwardly extending arm disposed in a plane above the base, of a main shaft journaled in the frame, a presser foot fixed to the front end of the arm and provided with an opening, a stitch forming mechanism mounted on the arm and including a needle mounted for reciprocations above the foot and across the opening therein, a work support mounted on the base to swing upwardly and downwardly relative to the foot and about a horizontal axis located in rear of the needle, means for normally retaining the work support yieldahly against depression, an oscillatory ridge forming disc operating in the presser foot opening for projecting a ridge of fabric upwardly into needle penetrating position and movable upwardly and downwardly with said work support, said disc having high and low peripheral work presenting portions arranged in tandem, an oscillatory shaft journaled on the work support and disposed in parallelism with the axis thereof and rigidly connected to said disc, and driving connections between the main and oscillatory shafts for operating the latter and including devices for retaining the oscillatory shaft against angular movement upon depression of the work support, said driving connections periodically presenting to the needle first one of said disc portions and then the other to thereby vary the effective depths of the needle penetrations, said devices including a lever fulcrumed on an axis located intermediate the work support pivot and the oscillatory shaft, a rock arm fixed to the oscillatory shaft, and a link connecting the lever and the rock arm.

7. In a blind stitch sewing machine, the combination with a frame including a base and a forwardly extending arm, of a presser foot rigidly attached to the free end of said arm, a work support mounted on the base to swing about a horizontal axis located in rear of the foot and having a portion disposed under'said foot, an upwardly and downwardly movable support for the work support, yieldable means-locatedbetween the movable support and the work support, for permitting a limited downward movementof thework support relative to the foot, releasable lockingmeans between the movable support and the basefor-normally, retaining said movable support against downward movement, and-manually operable means connected to said locking means for raising or lowering said looking means together with said ,movablesupport.

, 8.-In' a blind stitch sewing machine, the combination with a frame including a base and a forwardlyextending arm, of a presser foot rigidly attached to the free end of said arm, a work support mounted on the base to swing about a horizontal axis located in rear of the foot and having a portion disposed under said foot, an upwardly and downwardly movable support for the work support, yieldable means located between the movable support and the work support for permitting a limited downward movement of the work support relative to the foot, releasable locking means between the movable support and the base for normally retaining said movable support against downward movement, said locking means including an eccentric journaled on the base, and a toggle connection between the movable support and the eccentric, and manually operable means connected to said eccentric for rotating the latter to effect the raising or the lowering of said toggle connection together with said movable support.

9. In a blind stitch sewing machine, the combination with a frame including a base, a standard, and an arm extending forwardly from the upper end of the standard, of a presser foot rigidly attached to the free end of said arm, a work support mounted on the base to swing about a horizontal axis located in rear of the foot and having a portion disposed under said foot, an upwardly and downwardly movable support for the work support, yieldable means located between the movable support and the work support for permitting a limited downward movement of the work support relative to the foot, releasable looking means between the movable support and the base for normally retaining said movable support against downward movement, and means connected to said locking means and including a manually operable control element mounted on the standard for raising or lowering said locking means together with said movable support.

10. In a blind stitch sewing machine, the combination with a frame including a base, a standard, and an arm extending forwardly from the upper end of the standard, of a presser foot rigidly attached to the free end of said arm, a work support mounted on the base to swing about a horizontal axis located in rear of the foot and having a portion disposed under said foot, an upwardly and downwardly movable support for the work support, yieldable means located between the movable support and the work support for permitting a limited downward movement of the work support relative to the foot, releasable locking means between the movable support and the base for normally retaining said movable support against downward movement, said locking means including an eccentric journaled on the base, and a toggle connection between the movable support and the eccentric, and manually operable means connected to said eccentric for rotating the latter to effect the raising or lowering of said toggle connection together with said movable support, said manually operable means including a pinion fixed to the eccentric to rotate therewith, a rack bar slidably mounted on the base and engageable with the pinion, a manually operable element mounted on the main frame, and connections between said element and said rack bar for operating the latter.

11. In a sewing machine, the combination of a main frame including a base, a standard, and an arm extending forwardly and downwardly relative to the base from the upper end of the standard; and a work support mounted on the base and having a portion disposed in a plane below the free end of said frame arm, said work support being fulcrumed on a horizontal axis to swing upwardly and downwardly relative to said arm, said axis being disposed in a plane at right angles to the longitudinal axis of said arm and in rear of the free end of said arm.

12. In a sewing machine, the combination of a main frame including a base, a standard, and an arm extending laterally from the upper end of the standard and terminating in an arm extending forwardly and downwardly relative to the base; and a work support mounted on the base in front of the laterally extending arm and having a portion disposed in a plane below the free end of said forwardly extendingarm, said work sup portbeing fulcrumed on a horizontal axis to swing upwardly and downwardly relative to said free end, said axis being disposed in a plane at right angles to the longitudinal axis of said forwardly extending arm and in rear of the free end of said arm.

CHARLES W. MUELLER.

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