US3176639A - Trimming device for post sewing machines - Google Patents

Description

April 6, 1965 K. KLEEMANN ETAL 3,176,639

TRIMMING DEVICE FOR POST SEWING MACHINES 2 Sheets-Sheet l Filed June 27, 1962 illvfilllllll,

April 6, 1965 K. KLEEMANN ETAL 3,176,639

TRIMMING DEVICE FOR POST SEWING MACHINES Filed June 2'?, 1962 2 Sheets-Sheet 2 Fig.4

United States Patent O 3,176,639 G DEVICE FOR POST SEWING MACHINES s claims. (ci. 112-123) The invention relates to trimming devices for sewingV machines and is particularly concerned with trimming devices for post sewing machines of the type having a vertical looper shaft and a rocking shaft disposed parallel to the looper shaft.

Trimming means are already known whose driving components are disposed within the cross-section of the post or pedestal of the machine. However, the known arrangements of this type are equipped with cutters that swing in vertical planes. Therefore, they can only be employed for such tailoring operations which start at the beginning of the work blank and are not interrupted during the sewing operation and are again continued.

lt is an object of the invention to arrange a material trimming device on post sewing machines having a cutter which swings in a horizontal plane in such a manner that a post of relatively small'cross-section can be utilized. In accordance with the invention this is accomplished in that the rocking shaft which is in the form of a hollow shaft is journalled on the looper shaft. This provides for an extremely narrow post in spite of the drive means for the trimmer being arranged within the post, so that it is possible, for example, to hang the uppers of shoes over the post during the stitching and trimming of the heel lining, thus substantially facilitating the execution of such operations.

It is of particular advantage to construct the trimming device in such a manner that a cutter carrier which extends from the rocking shaft to the top side of the looper and laterally thereof carries a cutter which is arcuately shaped in a manner corresponding to the radius of its path of operation and swings about the axis of the looper. In this manner an optimum post cross-section is achieved because, as viewed in the' direction of feed, the right side of the post becomes only negligibly wider than the diameter of the double stitch looper. The cutter which swings about the axis of the looper is thus provided with a short lever arm so that vibrations are avoided to the greatest possible extent during trimming operations.

It is a further objectV of the invention to form the looper closure plate in a manner that during operation the cutter swings above the looper closure plate, while in inoperative position it is received in a part thereof which is raised and is provided with an entrance opening for the cutter, thereby eliminating the cutter protector which heretofore was normally required. The trimmer or cutter is thus received in the looper closure plate when it is inoperative so that on the one hand it is located in a position which is readily accessible for the operator, while on the other hand catching or tangling of the thread on the trimmer and cutting thereof is not possible even when the loops are loosely formed.

A structurally simple level adjusting means for the cutter or trimmer is obtained in that-an eccentric bolt carrying a sliding roller and which can be adjusted from the outside extends into a horizontal guide track of the cutter support or carrier.

Further advantages and objects of the invention will become apparent from the following specification and by reference to the accompanying drawings which illustrate an embodiment of the invention and in which:

FIG. 1 is a front View of a sewing machine incorporating the invention;

FIG. 2 is a Section of the post of the machine taken from the front and drawn to an enlarged scale;

FIG. 3 is a perspective view of the looper closure plate; and

FIG. 4 is a simplified perspective view of the driving mechanism.

As shown in FIG. 1, the machine comprises a base plate l, post 2, socket 3, standard 4, arm 5 and machine head 6. The arm shaft 7 is journalled in the customary manner in the arm of the machine, and it is operatively connected at its forward end with a needle bar 9 which supports a needle 8 and -is reciprocably movable in the machine head.

A pinion 10 is provided upon the arm shaft which, by way of a pinion 11, drives a shaft 12 arranged in the standard 4. At the lower end of this shaft 12 a further pinion 13 is fastened, which by way of a counter pinion 14 passes on the driving force to a looper drive shaft 15 which is horizontally journalled in the base plate 1. The shaft 1S supports a pinion 16 at its forward end which meshes with a counter pinion 18 mounted upon a vertical looper shaft 17 journalled in the post 2.

At the upper end of the looper shaft 17 a double stitch looper 19 is provided which cooperates with the needle S and which is known per se.

Between two bearings 20, 21 of the looper shaft 17 a hollow shaft constituting a rocking shaft 22 is rotatably mounted around the looper shaft 17. The rocking shaft 22, the axial movement of which is limited by the upper side of the bearing 20 and by a collar 23 provided upon the looper shaft 17, supports a crank 24 proximate its lower end to which a draw bar 25 is linked which, in turn, is operatively connected by way of a drive mechanism. The drive mechanism for the rocking shaft 22 is accommodated partly below the base plate 1 and partly in a housing Sil secured on top of said plate, and it comprises a draw bar 51 encompassing an eccentric member 26 secured to the looper shaft 17. The forward end of said draw bar 51 is pivotally supported upon a bolt 52. A link 53 is secured to the bolt 52 below the draw bar 51, the free end of which is pivotally supported upon a pivot member 54 which supports at its upper end one arm S5 of a bell crank lever 56, which is turn is pivotally supported by a pivot bolt 58. Arm 57 of the bell crank lever is linked to a draw bar 25 which is pivotally connected to a crank arm 24 provided upon rocking shaft 22.

A further link member 59 is secured to the guided bolt 52 which is rotatably supported upon a shaft 60 and is provided with an arm 61 for vertically guiding the bolt 52. The arm 61 is slidable in a guide slot 62 in the housing 50. rI'here is furthermore connected to the shaft 60 a bell crank lever 63 having an arm 64 rotatably supported by means of a pin 65 secured in the housing 50. The arm 66 of bell crank lever 63 has a pin 67 which extends into a slot 68 of a setting disk 69. The setting disk 69 is rotatably supported on a bolt 70 which is also secured to the housing 5t) and which carries a setting lever 71 which is connected to the pivot bolt 58. A further crank 27 is secured upon the rocking shaft which by way of a pin 29 received in a slot 2S is in operative connection with a cutter carrier or support 36 that is movable longitudinally of the rocking shaft.

The cutter carrier 30 which extends laterally of the rocking shaft to the upper side of the looper has a support member 32 which carries a cutter or trimmer 31. The trimmer 31 which rocks about the looper shaft 17 is arcuately shaped in a manner corresponding to its path f Patented Apr. 6, 1965 :savanne 3 of movement and is provided with an elongated slot (not shown) so that the distance. `between needle 8 and the trimmer 31 is adjustable within limits by means of a screw 33.

A looper closure cover 35 is pivotally mounted on the post 2 by means of a hinge 34 with the top side 36 of the cover extending substantially parallel with respect to the rocking plate of the trimmer 31. Along the right side of the post as seen in the direction of feed, the looper cover 35 is bent upwardly and is provided at its rear portion with an aperture 37. Thus the double stitch looper and the elevated portion 38 of the looper closure form an intermediate space 39 which receives the trimmer. The trimmer in its operative position swings above the horizontal upper side 36 of the looper cover, while in its position of rest it is withdrawn through the aperture 37 and received in the intermediate space 39 and thus disappears completely below the looper cover.

Laterally of the post 2 an arrangement is provided for setting the cuttingk level or height of the trimmer. A bolt 41 journalled in the wall 40 of the post 2 is provided at one end with an eccentric lug 42. The lug 42 which mounts Va sliding roller 43 extends into a horizontal guide track 44 of the trimmer carrier or support 30. A setting lever 46 is secured on the part 45 of the bolt 41 which extends from the post 2 whereby the trimmer carrier 30 and thus the trimmer 31 can be raised and lowered in a manner corresponding to the eccentricity of the lug 42.

The trimmer 31 is moved fromitsinoperative position into operative position by rotating the setting lever 71, and its thrust is adjusted by rotating the setting disk 69. As this disk is rotated the pin 67 and thus the bell crank lever 63 are rotated about the pin 65, thus causing the shaft 60 to move simultaneously about the pin 65, and in this manner the shaft 60 is moved to a position which is closer or further removed from the pivot member 54. The magnitude of the thrust of the cutter will correspond to the lateral distance of the shaftV 60 from the pivot member 54. Y

As the looper shaft 17 isfrotated, the eccentric member Z6 imparts reciprocating movement to the bolt 52 by way of draw bar 51. At the same time the link 59 effects a rocking movement about the rocking shaft 60 causing link 53 to effect a rocking movement about the pivot member 54 and in addition a movement in its longitudinal'direction whereby the arm 55 of the bell crank lever 56 is rotated about the pivot bolt 58. As a result also arm 57 swings about the pivot bolt 58 and effects the rocking movement necessary forcutting or trimming by way of the draw bar and crank 24.

i If the shaft 60 is swung by rotation of the setting disk 69 to such an extent that it is in alignment with the pivot member 54, then both links 53, 59 rock about a common shaft 54, 6i), so that due to the same effective length of the two links no component of movement longitudinally of the link 53 is developed, thus causing the bell crank lever 56 to remain inactive, and therefore cutter 31 stands still.

Having now described our invention with reference to the embodiment illustrated in the drawings, we do not We claim:

1. Trimming device for post sewing machine of the type having a looper provided proximate and within the upper end of the work supporting post, said machine having a looper shaft supporting said looper and disposed in vertical positon in the post of the machine and a hollow rocking shaft journalled around said looper shaft, a trimmer carrierV supported by said rocking shaft, a trimmer of arcuate conformation supported by said trimmer carrier and movable with said carrier about the axis of said looper shaft, said trimmer carrier having a horizontally disposed guide track, and a bolt having a setting lever mounted externally of said post and supported by said post having an eccentric member extending into said track.

2. Trimming device for post sewing machine of the type having a looper provided proximate land within the upper end of the work supporting post, said machine having a looper shaft supporting said looper and disposed in vertical positon in the post of the machine and a hollow rocking shaft journalled around said looper shaft, a trimmer carrier supported by said rocking shaft, a trimmer of arcuate conformation supported by said trimmer carrier and movable with said carrier about the axis of said looper shaft, said post having a looper cover presenting an elevated portion and a horizontal surface at a lower level than said elevated portion, said elevated portion defining an aperture proximate said horizontal surface for permitting movement of said trimmer therethrough and to receive said trimmer while in inoperative condition.

3. Trimming device for post sewing machine of the type having a looper provided proximate and within the upper end of the work supporting post, saidrmachine having a looper shaft supporting said looper and disposed in vertical positon in the post of the machine and a hollow rocking shaft journalled around said looper shaft, a trimmer carrier supported by said rocking shaft, a trimmer of arcuate conformation supported by said trimmer carrier and movable with said carrier about the axis of said looper shaft, said trimmer carrier having a horizontally disposed guide track, and a bolt having a setting lever mounted externally of said post and supported by said post having an eccentric member extending into said track, said post having a looper cover presenting an elevated portion and a horizontal surface at a lower level than said elevated portion, said elevated portion and said horizontal surface defining an aperture therebetween for permitting horizontal movement of said trimmer therethrough.

References Cited-by the Examiner UNITED STATES PATENTS 1,401,973 l/22 Fifeld 112-252 1,883,654 lO/32 Ericsson 112-252 2,903,233 9/59 Magor 74-50 X FOREIGN PATENTS 499,292 l/ 39 Great Britain.

JORDAN FRANKLIN, Prmmy Examiner.

DAVID J. WILLIAMOWSKY, ROBERT V. SLOAN,

Examiners.

Claims (1)

1. TRIMMING DEVICE FOR POST SEWING MACHINE OF THE TYPE HAVING A LOOPER PROVIDED PROXIMATE AND WITHIN THE UPPER END OF THE WORK SUPPORTING POST, SAID MACHINE HAVING A LOOPER SHAFT SUPPORTING SAID LOOPER AND DISPOSED IN VERTICAL POSITION IN THE POST OF THE MACHINE AND A HOLLOW ROCKING SHAFT JOURNALLED AROUND SAID LOPER SHAFT, A TRIMMER CARRIER SUPPORTED BY SAID ROCKING SHAFT, A TRIMMER OF ARCUATE CONFORMATION SUPPORTED BY SAID

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