US2825294A - Adjusting means for sewing machine trimmer mechanism - Google Patents

Description

March 4, 1958 B. NT. PIERCE -2,8?5394 ADJUSTING ME NS FOR sswmc MACHINE TRIMMER 'Mscmurs Filed Nov. 29, 1954 4 Sheets-Sheet 1 fizve'ntor:

BernardNPierce M v M jyo'sAttorneys March 4,1958

- B. N. PIERCE 2,825,294

' ADJUSTING MEANS FOR SEWING MACHINE TRIMMER MECHANISM v Filed Nov. 29, 1954 4 Sheets-Sheet 2 lllll Fl In vn'tor:

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B. N. PIERCE March 4, 1958 ADJUSTING MEANS FOR SEWING MACHINE TRJIMMER MEcHmIsM Filed Nov. 29, 1954 4 Sheets-Sheet 5 In 2: enter Bernard ill-Pierce wwm fiisAtornage' March 958 B. N. PIERCE I 2,825,294

ADJUSTING MEANS FOR SEWING MACHINE TRIMMER MECHANISM Filed Nov. 29, 1954 4 Sheets-Sheet 4 .9 z a/ z Z I His Alfofineys ADJUSTING MEANS FOR SEWING MACHINE TRIMMER MECHANISM Bernard N. Pierce, West Hartford, Conn., assignor to The Marrow Machine Company, Hartford, Conn., a corporation of Connecticut Application November 29, 1954, Serial No. 471,566

9 Claims. (Cl. 112-125) This invention relates to trimming mechanism for sewing machines and more particularly to a shiftable trimming mechanism.

A typical overseaming machine having a trimming mechanism to which my invention has particular application forms the subject matter of United States Letters Patent No. 1,207,063, granted to Joseph M. Morrow, December 5, 1916. in machines of this type, a cutter carrier is oscillated in a plane which is fixed relative to the frame of the machine. Work material is stitched and fed past the oscillating cutter mechanism which trims the edges of the material parallel to and at a fixed distance from the line of stitch formation. A feed mechanism is provided to advance the work material past the oscillating cutter mechanism.

One object of the invention is to provide an improved assemblage in which a shiftable trimmer mechanism and a presser-foot mechanism are cooperatively supported in their assembled relationship.

Another object of the present invention is to provide an improved shiftable trimmer mechanism in which adequate lubrication of the various parts is assured.

In the statement of these objects, an important feature of the invention resides in the arrangement of a shaft journaled in the mechanism compartment of the sewing machine frame for rotatable and axial movement relative to the frame with a cutter carrier mounted upon the shaft and so proportioned that axial clearance is provided beof the shaft and cutter carrier upon operation of a hand lever to turn the cam. This axial shifting of the cutter carrier enables the width of the margin between the edge of the material and the line of stitch formation to be varied at will. A stop mechanism at one end of the shaft defines the limits of adjustment as well as to bias the adjustment mechanism to a home" or reference position. Oilite bearing bushings are employed to assure adequate lubrication of the shaft.

Preferably the shaft is hollow and the presserfoot mechanism has a carrier plate with an integral stud which projects into the hollow shaft. The carrier plate of the presserfoot assembly is thus pivotally supported by the hollow shaft or sleeve and may be confined against axial movement by cooperating bearing surfaces on the machine frame engaging opposite sides of the carrier plate.

Other objects and advantages of the invention will be apparent from the followingdetailed description and the accompanying drawings.

In the drawings: I

Fig. 1 is an elevation of the leftend of a sewing machine embodying the invention;

Fig. 2 is a vertical transverse section through the machine frame at the right of trimming mechanism which, 7 tained'in cutting relationship.v

in this view appears in elevation;

.I 'nited States Pa n 0 Fig. 3 is a section on line 3-3 of Fig. 2;

Fig. 4 is a view similar to Fig. 3 but shows therein a bore-filling plug substituted for certain parts shown in Fig. 3;

Fig. 5 is a fragmentary right end elevation of the machine showing elements of trimmer shifting mechanism;

Fig. 6 is a rear elevation of trimmer shifting elements shown in Fig. 5;'and

Fig. 7 is a sectional view substantially on line 77 of Fig. 3. r

Referring to the drawings, the sewing machine illustrated, as including mechanism comprising my invention, is of the Merrow type high speed trimming and overseaming machine. The frame of the machine is formed by a main casting 1, having a mechanism compartment 2, through which are extended a driving lower shaft 3 and an upper shaft 4 (see Fig. 2). From the upper shaft 4 are actuated certain elements that form part of trimming mechanism embodying the present invention, movable parts of other mechanism for which compartment 2 is provided are not shown.

The lengthwise extent of compartment 2 is established by a front or left end wall 7 of machine frame 1 and a wall or partition 8 extending transversely of the machine frame intermediate its ends. The rear side wall 9 of compartment 2 is set back of the rear side of the narrower part 11 of frame 1, thus an offset is extended from compartment 2 that provides room therewithin for elements of trimming mechanism to thereby secure an advantage that will hereinafter be more apparent.

Formed in wall 7 and in an inward extension or thickening 12 of wall 9 are axially aligned bores 14 and 15 in parallelism with shafts 3 and 4. Oilite bearing bushings 16 and 17 are respectively held in bores 14 and 15 by screws 18 and 19, and within these bushings is journaled I a hollow shaft 20 having secured thereto by screw 21 an upper cutter carrier 22. Access to screw 21 is provided by hole 23 in wall 9 of the machine frame. Hollow shaft 20 is supported within bearings 16 and 17 for both rotary and axial movement. Hollow shaft 20 is, in effect, a rock shaft which defines the axis about which cutter carrier 22 is driven in rotary oscillation by upper drive shaft 4. Axial movement of hollow shaft 20 relative to machine frame 1 serves to position the cutting elements mounted at the distal end of carrier 22 at selected distances from the line of stitching as will be developed in greater detail below.

A presserfoot assembly 25 is pivotally supported by stud 26 within hollow shaft 20. This assembly 25 includes a presserfoot arm 27 pivotally supported by screw 28 on a presserfoot-arm carrier 29. Preferably formed integrally with carrier 29, stud 26 forms a pivotal support in bearing bore 30 of hollow shaft 20. For holding presserfoot-arm 29 for oscillation in a desired plane it is confined against axial movement by a fiange 31 forming a part of the carrier that is engaged on one side by finished surface 32 of machine frame 1 while on the other side the flange is engaged by an overlying lip 33 6Xll61'1d' ing from a block or bracket 34 secured to machine frame 1 by screws as 35.

From the foregoing description it will be apparent that while stud 26 is axially immovable relative to machine frame 1, hollow shaft 20 is free for axial and oscillatory Upper cutter carrier 22 adjacent its distal end is.

formed with a laterally extending arm to which clamping elements 41 and 42 are secured by screws 41' and 42"respectively. Element 41 is adjustable lengthwise of arm 40 and cutter blade 36 is adjustable relative to element 41'. These respective adjustments may be, effected with screws 41' and 42' slightly loosened.

Lower cutter-blade 37 is secured to a movable slide 45 by a clamp 46 formed with a stem 47 threaded to ,engage an actuating nut 48 seated-in a countcrbore 49 of slide 45. Slide 45, mounted upon a support 50, that is secured to machine frame 1, is movable to engage lower cutter blade 37 with upper cutter blade 36, between which cutting blades yielding engagement is maintained by a spring 51 interposed between slide 45 and a spring abutment plate 52 that is secured to support as by screw 53.

Hub 55 of upper cutter carrier 22 is axially movable within limits established by the opposed ends of bushings 16 and 17. With carrier 22 in the position in which it is shown in Fig. 3, and upper cutter blade 36 adjusted on the carrier as shown, the plane of cutting action would coincide with line 57 at a distance X from the line of stitch formation indicated by line 58. The distance X represents the width of margin of material defined or enclosed by stitching. To vary the width of margin X, a manually controlled arrangement is provided that serves to shift shaft 20 together with cutter carrier 22 whatever amount may be desired. Such an arrangement includes a rotatable cylindrical cam element 59 journaled in a slightly enlarged continuation 60. of bore 15. Formed, in the periphery of element 59 is a spirally disposed groove 61. This cam groove 61 is engaged by the end 62 of a screw 63 so that element 59 is moved axially as it is rotated. Such axial movement of cam element 59 imparts like movement to hol ow shaft 20 through a swivel connection 65. This swivel joint includes a T-head stud 67 having a shank 68 that is secured in bore 30 of hollow shaft 2%) by a pin 69. When cam 59 is turned and moved axially, axial movement throu h the swivel connection is also imparted to hollow shaft 20 to thereby shift cutter carrier 22 for the purpose above set forth. For actuating this cutter shifting mechanism there is provided a hand lever 70 which is secured by a screw 71 to reduced end, or stud 72 of cam element, 59. Stud 72 is journaled in a support 74 having a reduced or pilot end 75 to engage bore 60., Securing support 74 to machine frame 1 are screws as 76. A gasket 77 is interposed between the machine frame surface 78 and shoulder 80 of support'74.

In Fig. 5. lever 70 is shown in what may betermed normal position. Means for yieldably maintaining this position include a detent 81 endwise movable in a socket 82 of a lug 83 which extends laterally from lever arm 70 adjacent lever hub 85. A spring 86 acts to yieldably engage an inclined surface 87 of detent 81 against an opposed eccentric surface 88. of support 74 thereby urging lever 70 to turn in a counter-clockwise direction as seen in Fig. 5. A limiting stop, to arrest movement of lever 70 in this counter-clockwise direction, comprises a pin 90 extended from lever hub 85 and engageable with a stop surface 91 formed on support 74. With lever 70 in this normal position, cutter carrier 22, through intermediate parts is established in the position in which it is shown in Fig. 3. In this position of the cutter carrier 22, cutter blades 36 and 37 may be adjusted to whatever position is required to establish the plane of trimming actionwhere it will effect the minimum width of margin desired, as for example, the width indicated by X. From this position manipulation of leve 70, in a clockwise direction, as seen in Fig 5, increases the distance X to widen the margin of material indicated or enclosed by the stitching. The amount of increase of width of margin X depends; upon the. amount of movement (clockwise) imparted to lever 70. An adjustable stop is provided by means of which the amount of such movement is determined. Such a stop may comprise a screw as 93 supported in a lug 94 extending peripherally from support 74. The point of screw 93 intercepts a path traversed by a stop pin 95 extending laterally from the hub 85 of lever 70. To maintain desired adjustment of screw 93, a check nut 96 is provided.

It will be apparent that lever 70 in other than its normal position and unheld by an operator would tend to be maintained .so placed by merely the effect of friction between the point of detent 81 and peripheral surface 97 of support 74. To increase the deterrent effect of detent 81 alone and thereby prevent accidental displacement of lever 70, a friction plug 98, as of leather, is applied with suitable pressure against cam element 59 by screw 99.

Axial movement of hollow shaft 20 and cam element 59 within bore 15 and its enlargement 60, require that air vents be provided leading from the clearance space thereabo-ut. Otherwise this space would be practically air-tight and movement of the parts therewithin would be more or less resisted. Such vents comprise holes 100 and 101 in T-head stud 67, hole 102 in machine frame 1 and hole 103 in cam element 59 (see Fig. 7). Hole 1130 is of sufficient diameter to avoid being entirely blocked by pin 69.

The foregoing description is directed especially to mechanism supplied with a sewing machine to render trimming elements therein shiftable at will during operation of the machine to vary Width of a trimmed margin of material. Without the particular mechanism whereby trimming cutters are adjustable as set forth, the arrangement of trimming mechanism in the sewing machine shown is considerably simplified in that manually operable cam 59 and the swivel connection 65 employed with the more elaborate arrangement may be omitted. However, in utilizing, for the simpler form of trimming arrangement, a machine frame that is bored for the shiftable trimmer feature, a substitute element is preferably provided to close bore 60 (see Fig. 4).

In the trimming mechanism arrangement wherein the trimmer cutter assembly, as a unit, is not shiftable, cutter carrier 22 is confined to a single plane, in its oscillatory movement, by bushing 16 and a bushing substituted for bushing 17. Thus a hollow shaft 112, to which cutter carrier 22 is secured by screw 21, is also held against axial movement. Hollow shaft 112 extends through bushing 110 and slightly therebeyond to substantially where enlargement 60 terminates adjacent bore 15. To close eulargement 60 of bore 15, a plug 113 is substituted for cam element 59, and. as, in this arrangement, support 74 is omitted, there is no need to provide a finished machine frame surface as 78 to oppose the shoulder of a bushing such as 80. Plug 113 is grooved at 114 to receive the point of a set screw 115 and is also grooved at 117 to receive a compressible gasket 118 commonly known as an O-ring. The outer end of plug 113 extends slightly beyond surface 119 of machine frame 1 and is grooved as at 120 for a purpose that is about to be explained. The inner, end of plug 113 is extended in a terminal 121 of reduced diameter. To install plug 113 it is inserted in core 60 until terminal 121 engages the end of hollow shaft 112. In this position groove 114 is slightly to the left of central alignment with set screw 115. Therefore when screw 115 is advanced to secure plug 113 the latter is so moved axially as to leave a clearance space between the end of terminal 121 and the end of hollow shaft 112.

The matter of removing plug 113 may be facilitated by engaging with groove 120 the point of a screw driver so that with the shank of the screw driver fulcrumed against a shoulder of the machine frame, plug 113 may readily be extracted.

It is to be understood that mechanism housed within compartment 2 includes substantially all movable surfaces oftrimmer mechanism parts that need ample and continuous application of lubricant. Such lubricant distribution is assured by the system of lubrication disclosed in my copending patent application Serial No. 257,620 filed November 21, 1951, wherein is described how lubricant is conducted by various surfaces to areas where lubrication 15 especially required and also plentifully discharged centrifugally from rotating elements so that deposit of lubricant is omitted from no area within compartment 2. Thus oilite bearings 16, 17 and 110 expose sufficient area to absorb their requirement of lubricant and from these porous bushings lubricant is supplied to rotating elements ournaled therewithin. To conduct lubricant to stud 26 holes 123 and 124 may be provided in hollow shafts 20 and 112.

While I have illustrated and described one embodiment of my invention. it will be readily apparent to those skilled in the art that the specific design disclosed is capable of modifications which fall within the purview of my inventive concept. Therefore, the disclosed embodiment is to be considered exemplary rather than limiting and the true scope of my invention is that defined in the following claims.

I claim:

1. In a sewing machine having a frame defining an enclosed mechanism compartment, a pair of spaced axially aligned bearings fixedly mounted in said frame, a hollow shaft within said mechanism compartment supported by said bearings, cutter means fixedly mounted on said hollow shaft between said bearings, a stud extending through said frame into said hollow shaft and rotatably supported thereby, a presserfoot including a carrier plate mounted on said stud externally of said compartment, means engaging opposite sides of said carrier plate to restrain axial movement of said stud and said plate relative to said frame, and means for axially shifting said hollow shaft to shift said cutter means relative to said frame.

2. In a sewing machine having a frame defining an enclosed mechanism compartment, a first bearing fixedly mounted in and extending through a first wall of said frame, a second bearing mounted Within a thickened portion of an adjacent wall of said frame, said second bearing being spaced from and axially aligned with said first bearing, a shaft supported by said hearing within said mechanism compartment, cutter means mounted upon said shaft between said bearings, means for driving said cutter means in oscillating rotary movement about the axis of said shaft, cam means journalled in said thickened portion of said adjacent wall spaced from and axially aligned with the end of said shaft, means connecting said shaft and said cam means, said connecting means permitting free relative rotation between said shaft and said cam means while holding said cam means and said shaft in fixed axial relationship, manually operable means for imparting rotary movement to said cam, and means for translating rotary movement of said cam into axial movement to move said cutter means and said shaft axially relative to said bearings.

3. In a sewing machine having a frame defining an enclosed mechanism compartment, a first bearing fixedly mounted in and extending through a first wall of said frame, a second bearing mounted within a thickened portion of an adjacent wall of said frame, said second bearing being spaced from and axially aligned with said first bearing, a hollow shaft supported by said bearings within said mechanism compartment, cutter means fixedly mounted upon said shaft between said bearings, a presserfoot comprising a carrier plate located externally of said compartment, a stud'integral with said carrier plate and extending into said hollow shaft to pivotally support said presserfoot therein, means for restraining axial movement of said carrier. plate and said stud relative to said frame, means within said mechanism compartment for driving said cutter means in oscillating rotary movement about the axis of said hollow shaft, cam means journaled in said thickened portion of said adjacent wall and axially aligned with said shaft, means connecting said shaft and said cam means, said connecting means permitting free rel- 6. ative rotation between said shaft and said cam means while holding said cam means and said shaft in fixed axial relationship, manually operable means for imparting rotary movement to said cam, and means for translating rotary movement of said cam into axial movement thereof to move said cutter means and said shaft in an axial direction relative to said frame and said stud.

4. In a sewing machine, a frame, a hollow shaft journaled in a wall of said frame for rotation relative to said frame, cutter means carried by said shaft for rotation therewith, a stud extending through said wall and rotatably supported within said hollow shaft, and a presserfoot mounted on said stud for rotation relative to said frame.

5. In a sewing machine, a frame, a hollow shaft journaled in a wall of said frame for rotation relative to said frame, cutter means carried by said shaft for rotation therewith, a stud extending through said wall and rotatably mounted Within said shaft, a presserfoot supporting carrier plate fixedly mounted on the end of said stud outside said wall, and means engaging opposite sides of said plate to restrain axial movement of said stud and said plate relative to said frame.

6. In a sewing machine, a frame having an end wall and a rear wall, a hollow shaft, bearing means rotatably mounting said shaft in said end Wall and a thickened portion of said rear wall, a stud extending through said end a wall and rotatably mounted within said hollow shaft, and a presserfoot supporting carrier plate fixedly mounted on the end of said stud outside said end Wall for rotation about the axis of said stud relative to said frame.

7. In a sewing machine, a frame, a hollow shaft journaled in a wall of said frame for rotation and axial movement relative thereto, cutter means carried by said shaft, means for axially shifting said shaft to locate said cutter means in selected axial positions relative to said frame, a stud extending through said Wall and rotatably mounted within said hollow shaft, and a presserfoot including a carrier plate mounted on the end of said stud and restrained by said frame against axial movement, and means for axially shifting said hollow shaft to adjust the position of said cutter means without shifting said carrier plate.

8. In a sewing machine, a frame, a hollow shaft journaled in a wall of said frame, cutter means carried by said shaft, cam means at one end of said shaft connected thereto for axially shifting said shaft to locate said cutter means in selected positions relative to said frame, a stud extending through said wall into the other end of said hollow shaft and rotatably mounted within said shaft, a presserfoot outside said wall mounted on said stud for rotation therewith and means on the exterior of said frame restraining said presserfoot against axial movement.

9. In a sewing machine, a frame, a hollow shaft extending through a wall of said frame, cutter means carried by said shaft, a cylindrical cam at one end of said shaft mounted in said frame for rotation relative there to, a swivel connection between said cam and said one end of said shaft, manual means for turning said cam to axially shift said cam and said shaft to position said cutter means in selected positions relative to said frame, a stud extending through said wall into the other end of said shaft and rotatably mounted within said shaft, 8. presserfoot carried by said stud for rotation relative to said frame about the axis of said shaft and means on the exterior of said frame restraining said presserfoot against axial movement.

References Cited in the file of this patent UNITED STATES PATENTS 1,418,682 Stedman June 6, 1922 1,602,140 Avis Oct. 5, 1926 2,293,607 Knaus et al. Aug. 18, 1942 2,427,609 Knaus Sept. 16, 1947 2,712,803 Schweda et a1 July 12, 1955 2,717,567 Hess Sept. 13, 1955

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