US2538271A - Trimming mechanism for sewing machines - Google Patents

Description

Ema, E6, 1951 ca. M. REIMER ET AL TRIMMING MECHANISM FOR SEWING MACHINES Filed June 21, 1949 6 Sheets-Sheet l INVENTORS.

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Jan. E6, 1951 G. M. REIMER ET AL 2,538,271

TRIMMING MECHANISM FOR SEWING MACHINES Filed June 21, 1949 6 Sheets-Sheet 2 IN V EN TORS. GEORGE M. REIME ALERT c. PETESOM ATTURZZEY.

Jan. 16, 1951 G. M. REIMER ET AL TRIMMING MECHANISM FOR SEWING MACHINES 6 Sheets-Sheet 5 Filed June 21, 1949 f. 5 M v 5 U 3 H Wang Mm INVENTORS. GEORGE M. REEMER ALBERT C. PETQRSQN av ,Z/- at. I.

ATTUEZYEY Jane 16, a. M. REIMER ET AL TRIMMING MECHANISM FOR SEWING MACHINES 6 Sheets-Sheet 4 Filed June 21, 1949 INVENTORDS. GEORGE M. REHWER ALERT C. PETERSON BY ATTUENEX Jan. 16, 1951 G. M. REIMER ET AL TRIMMING MECHANISM FOR SEWING MACHINES 6 Sheets-Sheet 5 Filed June 21, 1949 INVENTORS.

GEORGE M. REIMER ALBERT C. PETERSON BY 0. M

ATTORNEY.

Jan. 16, 1951 G. M. REIMER ET AL TRIMMING MECHANISM FOR SEWING MACHINES 6 Sheets-Sheet 6 Filed June 21, 1949 INVENTORS GEORGE REEMER ALERT G. PETESOM Patented Jan. 16, 1951 TRIMMING MECHANISM FOR SEWING MACHINES George M. Reiiner, Oak Park, and Albert 0. Peterson, Park Ridge, 111., assignors to Union Special Machine Company, Chicago, Ill., a corporation of Illinois Application June 21, 1949, SerialNo.10 0,316

9 Claims.

This invention relates to sewing machines, and more particularly to sewing machines equipped with improved trimming mechanisms whereby the machines are capable of simultaneously seaming and trimmin the edges of two or more plies of fabric.

It is the principal object of th invention to provide a sewing machine trimming mechanism having improved characteristics of construction and operation.

Another object of the invention is to provide a sewing machine having improved means for si- .multaneously stitching together and trimming the edges of a plurality of plies of fabric.

Another object of the invention resides in the provision of a sewing machine trimming mechanism having improved operating connections so constructed and arranged as to permit the trimming knife thereof to be easily and quickly placed into and out of active service.

Another object of the invention is to provide a sewing machine trimming mechanism wherein a reciprocatory sleeve carries a trimming knife blade and serves as a bushing for the machine presser bar.

Another object of the invention is to provide a sewing machine trimming mechanism wherein the parts are so arranged as to permit of ready adjustment to compensate for wear or to vary the trimming margin in a piece of work.

A further object of the invention is to provide a trimming mechanism that is adapted to be driven from within the hollow head of a sewing machine.

A still further object of the invention is to provide a sewing machine trimming mechanism that is compact and sturdy in construction, positive in operation, and capable of performing its intended functions in an efficient and trouble-free manner.

The trimming mechanism of this invention is intended for use and may be advantageously employed with conventional sewing machines including lock stitch sewing machines of the type having a frame consisting of a base, the upper surface of which constitutes a work support, a hollow standard, an overhanging hollow arm, and a hollow head at the end of the hollow arm remote from the standard and disposed above the throat plate and feed dog supported by the base. Such a machine includes a rotary drive shaft for imparting reciprocation to the usual needle bar positioned in the head and carrying a needle at its lower end. Also reciprocable in the head' is a presser bar having a presser foot at its lower extremity.

--erative engagement with the sleeve.

One of the principal features of the invention resides in the provision of a vertically reciprocable sleeve that extends through the bottom wall of th hollow head and serves as a combined holder for a trimming knife blade and bushing for the presser bar. Secured to the lower end of the sleeve is a vertically and horizontally adjustable knife blade reciprocable with the sleeve. The knife blade may be positioned to the side of the needle facing the standard or may be disposed to that side and forwardly of the needle, as will be explained further along. Further, the knife blade is adjustable vertically and horizontally with respect to the sleeve.

The invention includes means responsive to rotary movement of the drive shaft for imparting reciprocatory movement to the sleeve and, therefore, to the trimming knife blade. This means preferably comprises a rock shaft supported at the rear of the sewing machine head and devices for. translating rotational movement of the' drive shaft into oscillatory movement of the rock shaft. Aflixed to the rock shaft and oscillatable therewith is an arm that supports a latch that is adapted to be readily placed into and out of op- The parts are so arranged that adjustments may be read- .ily made to compensate for wear between the latch and the sleeve.

When the latch is in operative engagement with the sleeve, the sewing machine may be used for simultaneously stitching together and trimming the marginal portion of two or more plies of fabric. If desired, the machine may be used to carry out only its stitching operations by simply disengaging the latch from the sleeve. To effect reengagement between the latch and the sleeve, to

thereby permit of simultaneous stitching and trimming, the operator merely actuates a handle or finger piece attached to and projecting to one side of the sleeve, whereby the sleeve is moved to a position where it again becomes engaged by the latch.

- The reciprocatory trimming knife blade cooperates with a stationary blade positioned in the throat plate. The reciprocatory blade is preferably arranged at an angle of approximately 1 with the vertical so as to prevent undue wear of the blades as the reciprocatory blade descends durin its cutting stroke.

If the reciprocatory blade were not disposed on such an angle, the yieldin pressure on that blade would be greater toward the bottom of its stroke than at the top of its stroke.

' The foregoing objects, together with other objects, as well as the advantages obtainable by the practice of this invention, will be readily understood by persons skilled in the art upon reference to the following detailed description, taken in conjunction with the annexed drawings, which respectively describe and illustrate preferred arrangements of devices embodying the invention.

In the drawings:

Figure 1 is a view partly in vertical central cross section of a sewing machine equipped with an arrangement of apparatus embodying the invention;

Figure 2 is an enlarged view in end elevation of the sewing machine shown in Figure 1, as viewed from the left thereof, parts being omitted for better illustration;

Figure 3 is an enlarged view in rear elevation of the sewing machine head and the throat plate, the presser foot being omitted for .better illustration of other parts;

Figure 4 is an enlarged fragmentary view in front elevation of the sewing machine head and associated devices, partly in longitudinal cross section;

Figure 5 is a fragmentary view, partly in vertical cross section and illustrating one relative position of the sewing machine needle, the knife holder and blade, the presser foot, and the throat plate in the stitching zone;

Figure 6 is a, fragmentary top plan view of the work support, showing the relationship of the throat plate, the feed dog, the throat plate knife bar, and associated parts;

Figure '7 is a view in elevation of the knife holder sleeve and the parts carried thereby;

Figure 8 is a top plan view of the combined knife holder sleeve guide and stop;

Figure 9 is a view in front elevation of the adjustable knife holder;

Figure 10 is a view in side elevation of the adjustable knife holder shown in Figure 9;

Figure 11 is a top plan view of the knife bar;

Figure 12 is a view in side elevation of the knife bar shown in Figure 11;

Figure 13 is a view taken along line I3I3 of Figure 12;

Figure 14 is a view taken along line l4-I4' of Figure 12;

Figure 15 is an exploded view of an arrangement of devices that are actuated by the sewing machine driving mechanism to impart reciprocatory movement to the knife holder sleeve and associated devices; and

Figure 16 is a fragmentary view corresponding to a portion of Figure 2 and illustrating a modified form of trimmer arrangement wherein the trimming knife is positioned forward of the sewing machine needle.

Referring now to the drawings wherein like reference numerals denote corresponding parts throughout the several views, a sewing machine frame generally indicated by numeral 20 consists of a base 2|, having a top 22 that serves as a work support, a hollow standard 23 extending upwardly of the base, and a hollow arm 24, overhangin the base and terminating in a hollow head 25. Access is gained to the interior of the hollow head by removing a cover plate 26 which it attached to the head by a pair of screws 21 (Figure 1). The sewing machine has an upper horizontal rotary shaft 30. One end of this shaft extends through and beyond standard 23 and carries a combined handwheel and pulley 3| which cooperates with a V-belt and a motor (not shown) for imparting rotation to the shaft. The

other end of the shaft terminates in hollow head 25 and carries a crank head 32 that coacts with a link 33 in response to rotation of shaft 30 to impart reciprocation to a vertically reciprocable needle bar 34. As is indicated in Figure 2, the upper portion of the needle bar is positioned in a bushing 35 carried by head 25. A needle 36 is attached to the lower end of the needle bar in the usual manner. The parts are so arranged as to obtain one complete reciprocation of the needle for each revolution of drive shaft 30. The illustrated sewing machine includes a take-up 31 (Figure 2) which may be the same as or similar to the take-up disclosed in G. Sauer Patent 2,324,598, entitled Sewing Machine, to which reference may be had for details of construction and operation in this regard.

A lower horizontal rotary shaft 40 is journalled in base 2| and is driven through the medium of a spur gear traindisposed within hollow standard 23 and consisting of an upper gear 4| affixed to shaft 30, an intermediate gear 42 rotatable about the axis of a stub shaft 43, and a lower gear 44 secured to the right end of shaft 40, as viewed in Figure 1. Positioned below a throat plate 45 is a rotary book 46 (Figure 2) that is connected to shaft 40 and is adapted to cooperate with needle 36 in a well-known manner in formation of lock stitches. The driving mechanism for rotary hook 46 is preferably of the type that is illustrated and described in the Christensen et a1. Patent 2,113,572, entitled Lock Stitch Sewing Machine.

The feeding mechanism of the sewing machine includes a feed dog 41 that extends upwardly through a slot 48 in the throat plate (Figure 6). The feed dog is supported by a 4-motion feed bar 50, the rear end of which is pivotally connected to a rocker 5| (Figure 2). The rocker is oscillated about the axis of a stub shaft 52 by devices (not shown) whereby corresponding horizontal movement is imparted to the feed dog. For a full understanding of the construction and operation of the feed dog actuating mechanism, reference is had to G. Sauer et al. Patent 2,035,508 entitled Feeding Mechanism for Sewing Machines.

Mounted in the bottom wall of hollow head 25 is a vertically arranged stationary bushing 53 (Figures 2 and 4). A knife holder sleeve 55 is reciprocable in bushing 53 and is cut away at its upper and lower ends to define slots or apertures 56 and 51, respectively. Sleeve 55 is provided with an integral lateral extension 58 at its lower end (Figure '7). A stop collar 65 (Figures 7 and 8) is aifixed to the upper end of sleeve 55 by a pair of set screws 6! and 62 and is formed with an integral laterally projecting guide arm 63 bifurcated at its free end, as indicated at 6 4. Guide arm 63 registers with a vertical slot 65 formed in the rear wall of hollow head 25 (Figure 3), and is slidable along the path defined by the slot, thereby permitting of vertical reciprocatory movement of sleeve 65 but preventing angular movement of the sleeve about its axis. A spring 66 is connected at its lower end to set screw 62 and at its upper end to a pin stud 67 carried by and projecting laterally inwardly of the rear wall of head 25 (Figure 2). Spring 66 is stressed in tension and normally urges the assembly shown in Figure '7 in an upward direction.

A bracket 10 (Figures 9 and 10) is formed with an elongated horizontal slot H and is attached to extension 58 of sleeve 55 by screws 12. This 'slot and screw arrangement permits of ready horizontal adjustment of the bracket with respect to sleeve 55. A trimming knife blade 13, best shown in Figure '1, is formed with a vertical slot 14 and is attached to bracket by a pair of screws 15. Slot 14 and screws permit of ready vertical adjustment of knife blade 13 with respect to the bracket and, therefore, with respect to sleeve 55. The knife blade includes a cutting edge 15 and a finger or extension 11 that projects downwardly below the cutting edge. A handle or finger piece 18 (Figures land 5) is affixed to sleeve extension 58 by a screw 19 and is disposed in spaced relation to the side of knife blade 13 remote from needle 36.

Throat plate 45 is provided with an insert or knife bar 80 best shown in Figures 11-14. The knife bar is secured to the sewing machine base by screws 8! (Figure 6) and includes an upstanding stationary knife blade 82 adapted to cooperate with reciprocable knife blade 13 to trim plies of fabric during the stitching thereof by the machine. A guide plate 83, attached to the throat plate by a screw 34, is provided with an elongated slot 85 to permit of lateral adjustment, and is formed with a depression 85 (Figures 5 and 6). Plate 33 is notched so as to define with knife bar 80 a slot 81 adapted to receive finger 1'! of knife blade 13, whereby knife blade 13 is maintained in proper position with respect to stationary knife blade 82 in the course of operation.

Sleeve 55 also serves as the lower bushing for a presser bar 90 which has a presser foot 9| removably attached to its lower end by a screw 92 (Figures 2 and 4). The upper end of the presser bar is positioned in a stationary hopper presser bar bushing 93 that threadedly engages the upper wall of hollow head and that has a knurled head 94 to permit of vertical adjustment with respect to the hollow head. A compression spring 95 is concentric with presser bar 90 and bears at one end against the lower extremity of bushing 93, and at its other end against a collar 96 which embraces the presser bar and is secured thereto by a set screw 91. It will be evident from an examination of Figure 4 that spring 95 normally and yieldingly urges the presser bar and its press er foot downwardly with respect to the sewing machine head. Integral with collar 96 is a laterally extending arm 98 that registers with and is adapted to ride along slot 65 in head 25 to thereby prevent angular movement of the presser bar and the presser foot about the axis of the presser bar. Pivotally connected to arm 98 is a slotted link I05 that cooperates with an arrangement of devices including a pin I0 I, a presser foot lifting the lever I02 (Figure 4), and associated parts (not shown) to effect raising of presser bar as and presser foot 92 against the action of spring 95 and thereby permit a piece of work to be readily inserted in or removed from the sewing machine in a manner well known to the art.

Reference is next had to Figures 1, 2, 3 and 15 for an understanding of a mechanism or means I04 that is responsive to rotary movement of drive shaft 36 for imparting reciprocatory movement to sleeve 55 and, therefore, to knife blade 13. This means includes a pitman I55 having relatively large and small straps I06 and I01, respectively, at its opposite ends. Strap I535 embraces an eccentric i08 carried by and ro tatable with shaft (Figure 1). The pitman extends through an opening I09 in the rear wall of hollow hear-1'25 and its strap I01 is connected by a bolt H0 and a nut III to a connector H2 having an elongated arcuate slot II2'. Connector II2 includes a split clamping sleeve II3 that has a clamping screw H4. A rock shaft II5, journalled in a lug IIG carried by and positioned rearwardly of the hollow head, is afiixed to conmotor I I2 through the medium of its split sleeve H3 and clamping screw II4. A collar I I1 is connected to rock shaft II5 by set screws II8. This collar is disposed to the side of lug II6 remote from split sleeve H3 and cooperates with that sleeve to restrain the rock shaft against axial movement.

The rock shaft carries an integral arm I20 which has an extension I2I that projects into an aperture I22 in cover plate 26 (Figure 3). Extension I2I is provided with a through opening I23 that is parallel to the axis of the rock shaft and is formed with an internal shoulder I24. Ex-

tension I2I is an element of a latch that includes a pin I25 tapped at one end to receive the threaded end of a knurled stud I26. A helical compression spring I21 is concentric with the shank of stud I25 and bears at its opposite ends against pin I25 and shoulder I24 to normally urge the pin toward the right, as viewed in Figure 4. Pin I25 is normal to the axis of sleeve and is adapted to register with slot '56 in sleeve 55 (Figure 1) or ride along the outer peripheral surface of the sleeve, depending on the vertical position of the sleeve with respect to the pin. When pin I25 is in registry with slot 56, collar serves as a thrust wall for the pin.

For the purpose of outlining the mode of operation of this invention, it is assumed that the machine is assembled and the parts are in the relative position shown in Figures 1 and 2, with spring-pressed pin I25 in registry with slot 56 in sleeve 55. Upon rotation of upper horizontal shaft 30, needle bar 34 and needle 33 are recipro- Icated. Simultaneous with reciprocation of the needle, mechanism I04 is actuated to impart corresponding reciprocation to sleeve 55 and knife blade 13. This permits of concurrent stitching and trimming of plies of fabric passed through the machine. It will be apparent from an examination of Figures 2 and 15 that stroke of the knife blade may be readily adjusted by altering the position ofbolt IIO along slot 2' in connector '2.

If it is desired to carry out only the stitching operation, knife blade 13 may be readily placed out of service by merely retracting pin 25 out of slot 56 by manually moving stud I26 toward the left, as viewed in Figure 1, against the action of compression spring I21. When pin I25 is moved out of operative engagement with sleeve 55, the sleeve and knife blade 13 are moved upwardly by spring 66 to the position shown in Figures 2.

At such time as it may be desired to again place the trimming mechanism in active service, the operator merely presses downwardly on handle or finger piece 18, thereby moving sleeve 55 downwardly against the action of spring 60 until latch pin I25 and slot 56 are placed in alignment, whereupon the latch pin is moved into the slot due to the action of its spring I21.

Figure 16 corresponds to a portion of Figure 2 and illustrates a modified form of the invention wherein the parts are so arranged as to position knife blade 13 forwardly or in advance of needle .35. In this connection, a bracket I30, corresponding to bracket 10 of the earlier described embodiment of the invention, includes a forwardly projecting arm I3 I. The remaining parts may be the same as those earlier described herein.

From the foregoing, it is believed that the construction, operation, and advantages of my present invention will be readily comprehended by persons skilled in the art. It is to be clearly understood, however, that the forms of my invention herewith shown and described are to be taken as preferred examples of the-same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention as defined by the appended claims.

We claim: v

1. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, a vertically reciprocable presser bar carried by the head and extending through the bottom wall, and a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head,

said sleeve being coaxial with and constituting a bushing for the presser bar, means for normally. and yieldingly urging the sleeve in one direction with respect to the presser bar, a trimming knife blade secured to the sleeve and reciprocable therewith, and means responsive to rotary move-- ment of the drive shaft for imparting corresponding reciprocatory movement to the sleeve 2. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, a vertically reciprocable presser bar carried by the head and extending through the bottom wall, and a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head, said sleeve being coaxial with and constituting a bushing for the presser bar, means for normally and yieldingly urging the sleeve in one direction with respect to the presser bar, and means connected to the sleeve and operable from the exterior of the head for imparting movement to the sleeve in a reverse direction against the action of the first mentioned means, a trimming knife blade secured to the sleeve and reciprocable therewith, and oscillatory means independent of the presser bar engaging the drive shaft and the sleeve for translating rotational movement of the shaft into reciprocatory movement of the sleeve.

3. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, a vertically reciprocable presser bar carried by the head and extending through the bottom wall, and a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head, said sleeve being coaxial with and constituting a bushing for the presser bar, means for normally and yieldingly urging the sleeve in one direction with respect to the presser bar, and means connected to the sleeve and operable from the exterior of the head for imparting movement to the sleeve in a reverse direction against the action of the first mentioned means, means for preventing angular movement of the sleeve about its axis, said lastrnentioned means comprising a member connected to the sleeve and registering with and slidable along a path defined by a slot in the head, a trimming knife blade secured to the sleeve and reciprocable therewith, and oscillatory means independent of the presser bar engaging the drive shaft and the sleeve for translating rotational movement of the shaft into reciprocatory movement of the sleeve.

4. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, a vertically reciprocable presser bar carried by the head and extending through the bottom wall, and a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head, said sleeve being coaxial with and constituting a bushing for the presser bar, a trimming knife blade secured to the sleeve and reciprocable therewith, means responsive to rotary movement of the drive shaft for imparting corresponding reciprocatory movement to the sleeve, said means comprising an oscillatory member, means for translating rotary movement of the shaft into oscillatory movement of the member, and a latch carried by the oscillatory member and releasably engaging the sleeve, and means for adjusting the extent of reciprocatory movement of the sleeve.

5. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, a vertically reciprocable presser bar carried by the head and extending through the bottom wall, and a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head, said sleeve being coaxial with and constituting a bushing for the presser bar, a trimming knife blade secured to the sleeve and reciprocable therewith, and means responsive to rotary movement of the drive shaft for imparting corresponding reciprocatory movement to the sleeve, said means comprising an oscillatory member, means for translating rotary movement of the shaft into oscillatory movement of the member, and a latch including a spring-pressed pin carried by the oscillatory member and releasably engaging the sleeve.

6. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, a vertically reciprocable presser bar carried by the head and extending through the bottom wall, and a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head, said sleeve being coaxial with and constituting a bushing for the presser bar, a trimming knife blade secured to the sleeve and reciprocable therewith, and means responsive to rotary movement of the drive shaft for imparting corresponding reciprocatory movement to the sleeve, said means comprising a rock shaft, means connected to the drive shaft and the rock shaft for translating rotary movement of the drive shaft into oscillatory movement of the rock shaft, an arm secured to the rock shaft, and a latch secured to the arm and releasably engaging the sleeve.

'7. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, a vertically reciprocable presser bar carried by the head and extending through the bottom wall, and a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head, said sleeve being coaxial with and constituting a bushing for the presser bar, said sleeve having an aperture formed therein, a trimming knife blade secured to the sleeve and reciprocable therewith, and means responsive to rotary movement of the drive shaft for imparting corresponding reciprocatory movement to the sleeve, said means comprising a rock shaft, means connected to the drive shaft and the rock shaft for translating rotary movement of the drive shaft into oscillatory movement of the rock shaft, an arm secured to the rock shaft, and a latch secured to the arm, said latch including a spring-pressed pin movable into and out of registry with the aperture in the sleeve.

8. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, a verticallyreciprocable presser bar carried by the head and extending through the bottom wall, and a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head, said sleeve being coaxial with and constituting a bushing for the presser bar, spring means Wholly within the head for normally and yieldingly urging the sleeve upwardly with respect to the presser bar, a lever connected to the sleeve and operable from the exterior of the head for imparting movement to the sleeve in a downward direction against the action of the spring means, a trimming knife blade secured to the sleeve and reciprocable therewith, means for preventing angular movement of the sleeve about its axis, said last-mentioned means comprising a member connected to the sleeve and registering with and slidable along a path defined by a slot in the head, and means responsive to rotary movement of the drive shaft for imparting corresponding reciprocatory movement to the sleeve, said means comprising a rock shaft, means connected to the drive shaft and the rock shaft for translating rotary movement of the drive shaft into oscillatory movement of the rock shaft, an arm secured to the rock shaft, and a latch secured to the arm and releasably engaging the sleeve.

9. In a sewing machine having an overhanging arm, a hollow head at the outer end of the arm and including a bottom wall, vertically reciprocable presser and needle bars carried by the head and extending through the bottom wall, a needle secured to the lower end of the needle bar and. a rotary drive shaft, a vertically reciprocable sleeve extending through the bottom wall of the head,

said sleeve being coaxial with and constituting a bushing for the presser bar, spring means wholly within the head for normally and yieldingly urging the sleeve upwardly with respect to the presser bar, a lever connected to the sleeve and operable from the exteriorof the head for imparting movement to the sleeve in a downward direction against the action of the spring means, means for preventing angular movement of the sleeve about its axis, said last-mentioned means comprising a member connected to the sleeve and registering with and slidable along a path defined by a slot in the head, a trimming knife blade secured to the sleeve and reciprocable therewith, said knife being disposed to one side of the needle and being vertically and horizontally adjustable with respect to the sleeve, and means responsive to rotary movement of the drive shaft for imparting corresponding reciprocatory movement to the sleeve, said means comprising a rock shaft, means connected to the drive shaft and the rock shaft for translating rotary movement of the drive shaft into oscillatory movement of the rock shaft,

' an arm secured to the rock shaft, and a latch secured to the aram and releasably engaging the sleeve.

GEORGE M. REIMER. ALBERT C. PETERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 511,603 Fefel Dec. .26, 1893 630,209 Foster Aug. 1, 1899 668,184 Hill et al Feb. 19, 1901 1,433,705 De Voe Oct. 31, 1922 1,469,422 Luscher Oct. 2, 1923

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