Roll foot for sewing machines
United States Patent Schorb A r. 8 1975 HM ROLL FOOT FOR SEWING MACHINES 2.211.333 8/1940 Lang 112/-35 [75] Inventor: Werner Schorb. Karlsruhe.  
  Germany Prinmry Examiner-Richard J. Scanlan. Jr. I73] A I d t w k K l h Attorney. Agent. or Firm-McGlew and Tuttle ssignee: n us rieer e ar sru e Augsburg Aktiengesellsehafl.  
  Karlsruhe. Germany l57l ABSTRACT [23] m Man 23. 1973 A presscr foot for sewing machines comprises a foot having a vertical portion and a foot sole portion WhlCh l l PP N043 344J54 extends generally horizontally outwardly in a direction opposite to the feed direction of the material to be [30] Foreign Application priority Data sewn. Ana angle lever is arranged on each side of the M. H Gcmnm 8&#39;85 foot and has first and second leg portions with the second leg portion extending on respective sides of the t foot sole and carrying a plurality of rollers which are 1 spaced along the feed direction and with correspondg Fieid 161 714 ing rollers of each angle lever being transversely m is aligned. Means are provided for mounting the first leg portions of the angle levers on a lock member which is [56] References Cited slidable upwardly and downwardly on the foot and UNITED STATES PATENTS which may be clamped in an adjusted position. msxms 2/l928 Baynard 112/235 2 Claims- 2 Drawing Figures ROLL FOOT FOR SEWING MACHINES BACKGROUND OF THE INVENTION This invention relates in general to a construction of a sewing machine presser foot and. in particular. to a new and useful presser foot for sewing machines which includes angle levers which have horizontally extending portions with rollers therealong spaced in the direction of feed of the material and which are carried on a block member which may be adjustably positioned along the height of the vertical portion of the foot.  
 DESCRIPTION OF THE PRIOR ART The present invention relates particularly to a presser foot for a sewing machine in which it is desired to reduce the sliding friction during the advance of the material to be sewn, and particularly in materials having isothermal properties. In making seam connections, it is generally necessary to hold the work down by means of a mechanically operable device and for this purpose, so-called presser feet have long been known. To process material on sewing machines which have distinctive properties, for example materials of particular thickness or of particular characteristics such as leather. plastics and the like, it is known to provide presser feet with inserted rolls or roll feet with a roll mounted thereon. Because of the great demand for di versified leisure type clothing, it becomes necessary to form seams on materials having relatively slight sliding properties. In this category are the materials which are used for protective clothing such as for underwater swimming, water skiing, sailing anc canoeing. Underwater and water skiing suits, for instance, are sometimes made of neoprene or other material having special isothermal properties in order to keep the body temperature of the user as constant as possible even during prolonged stays in the water. Neoprenes are synthetic materials and as a result, such materials have a relatively high coefficient of friction. In addition, they generally have a smooth surface so that they are difficult to shift because of their adhesive friction properties. In sewing machine operations, however, the material must be continuously moved in order to form a seam and this is particularly difficult in the formation of neoprene diver suits. The materials for such suits must be shifted in the direction of the progressing seam during the forming operation by means of transport tools which are associated with the sewing machines and which operate without undue effort by the sewing machine operator.  
 SUMMARY OF THE INVENTION The present invention provides an arrangement of a presser foot assembly for sewing machines which is capable of handling materials with high adhesive friction and which may be adustably positioned in respect to the sewing machine foot. The presser foot assembly of the sewing machine includes two parallel angle levers having one leg which is pivotally mounted on a block which is adjustable vertically on the presser foot bar. The angle levers include horizontally extending portions with transversely aligned pairs spaced in the feed direction along each associated lever. A feature of the construction is that the levers may be displaced on the associated block mounting and the block mounting may be shifted vertically on the presser foot bar. Thus, the angle levers carrying the rollers which are engageable with the material may be adjusted both in respect to angle of approach and in respect to elevation. The height of adjustment of the rollers carried by the levers is effected by sliding a bearing pedestal or bearing block which mounts the levers upwardly and downwardly on the associated presser foot bar relative to the vertical portion of the presser foot. The adjustment of the inclination of the rollers relative to the horizontally extending presser foot sole is effected by means of clamping screws which are carried on one arm portion of each lever at a spaced location from the pivotal mounting of the lever on the block.  
  The invention provides a number of advantages: The device comprises very few parts which can be produced without great cost and the rollers carried by the angle levers may be of standard commercial design. A further important feature of the device is that it can be attached with ease on existing machines. A decisive advantage of the invention, is that it makes it possible to easily manipulate materials having great friction such as neoprene so that the work can be moved on in the seam forming operation satisfactorily by the transport tools of the machine and without any special physical effort by the operator. This work facilitating device will also have a favorable effect on the product quality as well as the quantity which can be produced.  
  Accordingly, it is an object of the invention to provide a presser foot construction and a device which is capable of being mounted on a presser foot which includes a block member which is adapted to slide on a vertical portion of the presser foot and which carries a lever arm at each end which has a horizontally extending portion on each side of the presser foot sole and wherein the horizontal portion carries a plurality of rollers spaced in the feed direction and wherein the arms may advantageously be shifted pivotally to change the angle of approach of the rollers and the block member may be adjusted for changing the height of engagement of the rollers.  
  A further object of the invention, is to provide a presser foot and/or presser foot attachement which are simple in design, rugged in construction and economi cal to manufacture.  
  For an understanding of the principles of the invention, reference is made to the following description of a typical embodiment thereof as illustrated in the ac companying drawing.  
 BRIEF DESCRIPTION OF THE DRAWING In the Drawing:  
  FIG. 1 is a front top perspective view of material which is to be sewn in a sewing machine having the invention; and  
  FIG. 2 is a front top perspective view of a sewing machine presser foot constructed in accordance with the invention.  
 GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings in particular, the invention is particularly applicable for operating on materials which are to be sewn such as indicated in FIG. 1 which includes strips 1 and la of a neoprene or similar material which, for example, comprise material for producing an isothermal protective garment. The strips 1 and la are arranged in abutting relationship and they must be joined together perfectly tightly by means of a cover strip 2 which overlaps the strips 1 and it: along a marginal area on each side of the abutting joint. The cover strip 2 is then sewn along seam lines 2a, 2b, 2c and 2d.  
  In accordance with the invention. as shown in FIG. 2. there is provided a presser foot 3 which already incluldes or which may be provided with supplementary means for engaging the material approaching the needle by low friction elements such as rollers. In the em bodiment shown. the presser foot assembly includes a usual vertical block portion 4 which is slidable on a sewing machine presser foot bar 311 and may be locked in an adjusted vertical position by clamping means comprising a locking bolt 5. The assembly also includes a presser foot having a vertical part 3a which is con nected to the presser foot bar 312 below the block portion 4. The free end of the bar 3/1 is connected to the sewing machine (not shown). The presser foot also includes a generally horizontally extending presser foot sole 3c. The block part has a bore through which the vertical bar portion 3h extends and the block may he slid along the height of the bar 3b and clamped in an adjusted position by tightening the clamping screw 5.  
  The block 4 also provides an adjustable support for a pair of angle levers 6a and 6 which are arranged on respective opposite ends of a block portion 4a which extends transverse to the feed direction The angle le vers 6 and 6a are pivotally supported on bolts [4 at the upper end of a first arm portion 6a and 6&#39; which, as indicated in the drawing. usually extends generally vertically. The arm portions 6a and 6&#39; may be pivoted about the axis of the bars 14 and anchored in an ad justed position by means of clamping screws 7 and 7a which are tightened within the bores of the assoiated angle levers and engage against the block part 4. The screws 7 and 7a are hexagonal socket screws in order to facilitate their securement when the arms 611&#39; and 6&#39; are in the adjusted position In accordance with a feature of the invention, the arms are pivoted angularly in order to adjust the angle of approach of horizontally extending portions or arms 61:&#34; and 6&#34; ofthe angle levers 6a and 6. These horizontally oriented arms 6a&#34; and 6&#34; carry rollers 8a. 9a. and 10a and 8, 9. ll) respectively and these rollers are arranged in spaced location proceeding in the direction of feed and the rollers of the respective arms are transversely aligned. The roller pairs 8a. 8, 9a 9 and 10a 10 which are arranged on the axis of the bars ll, 12, 13 engage material which is fed over a table 30 and they facilitate the holding down of the material as it is easily advanced. The rollers may be adjusted vertically by shifting the block member 4 along the bar 31) or they may be adjusted with respect to the angle of engage ment of the material by rotating the respective angle levers 6a and 6. The adjustment of the angle levers changes their inclination in respect to the sole 3: of the presser foot 3 and it may be easily done by loosening the screws 7 and 7a and shifting the angle levers 6a and 6 to a desired adjusted angular position and then retightening the screws.  
  While a specific embodiment of the invention has been shown and described in detail to illustrate the ap plication ofthe principles of the invention, it will be un derstood that the invention may be embodied otherwise without departing from such principles.  
 I claim:  
  1. A presser foot assembly for sewing machines. comprising a sewing machine bar. a foot bearing block part having a bore therethrough accommodating said bar, said block being vertically adjustably movable on said bar. clamping means for securing said block part at a fixed position along the length of said bar, and a foot sole having a horizontal portion and a vertical portion connected to said bar below said block, an angle lever on each side of said foot bearing block part pivotally mounted thereto in an adjusted pivotal position on said bearing block, said angle levers means fixing said angle levers having first leg portions pivoted on said block and second leg portions extending at an angle to said first leg portions. said second leg portions extending on respective sides of said foot sole horizontal portion, a plurality of rollers rotatably mounted at spaced locations along said second leg portions of each angle lever, corresponding rollers of respective angle levers being transversely aligned and being spaced in the direction of material feed, and means pivotally mounting said levers on each side of said block part of said vertical portion of said presser foot.  
  2. A presser foot assembly comprising a bar member of a sewing machine. a vertical part with a block portion and having a bore therethrough for receiving the bar member. clamping means for securing said vertical part to said bar member at a selected height thereon. first and second angle lever members, means pivotally mounting said lever members on respective ends of said block member and each lever member including an outwardly extending arm portion carrying at least one rotatable roller thereon, said angle lever members being rotatable in respect to said block member to adjust the inclination of said arm portion carrying said roller. clamping means for clamping said first and second levers in an adjusted position. and a lower presser foot portion connected to the bar below said block por tion and having an outwardly extending presser foot located between said angle lever member outwardly extending arm portions.