Patents Assigned to Pfaff Industriemaschinen GmbH
  • Patent number: 4154182
    Abstract: The sewing machine includes a drive shaft which is rotatably mounted in a housing and is connected to a needle to reciprocate the needle at a stitching area in order to effect sewing of material. A fan blade or impeller is affixed to the main shaft for rotation therewith, and it rotates in a chamber in the housing and is constructed with a central inlet opening to pull in air centrally and to discharge it radially downwardly into a lower extension below the oil pan of the sewing machine. The lower extension includes a plurality of ribs extending downwardly from the bottom wall of the oil pan which forms heat exchanger surfaces over which air from the blower is directed. The heat exchange surfaces are arranged in the form of longitudinally extending ribs which extend substantially parallel to the shaft and they define air flow channels therebetween.
    Type: Grant
    Filed: January 5, 1978
    Date of Patent: May 15, 1979
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Kurt Klundt
  • Patent number: 4152995
    Abstract: A sewing machine for sewing and feeding material has a rotatable main shaft in a housing which is connected to drive a reciprocating needle for reciprocation in a stitching area. Adjacent the needle is a presser rod which depends from the housing and a carrier is mounted on the rod for upward and downward movement and is biassed downwardly so as to press a feed roller rotatably mounted on the carrier against the material to be fed. A drive mechanism for the feed roller is mounted on a bracket extending outwardly from the housing, and it includes a rotatable drive gear which is driven intermittently through an oscillation mechanism driven from the main shaft. A substantially triangular rocker member is pivotally mounted on the same axis as the drive wheel, and it supports two spaced apart guide rollers over which a drive belt is guided. The drive belt is connected to the gear drive wheel and to a gearwheel on the feed roller to rotate the feed roller intermittently.
    Type: Grant
    Filed: March 17, 1978
    Date of Patent: May 8, 1979
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Kurt Klundt
  • Patent number: 4145985
    Abstract: A sewing machine having a rotatable main shaft connected to a needle to reciprocate it includes an impeller or air fan which has a hub portion which is connectable to the main shaft of the sewing machine for rotation thereby. The impeller housing also includes a plurality of radially extending fans defining air flow passages therebetween and a central axially extending tubular inlet forming the inlet for inward axial flow and then radial outward flow and peripheral discharge for circulation of the air through a cooling chamber defined in the sewing machine below the oil pan housing part. The impeller also includes an exterior groove around the tubular part which defines a pulley for a V-belt so that the impeller may function as a drive for the shaft. In addition, a hand wheel is secured around the periphery of the tubular part to facilitate hand rotation of the shaft. The hand wheel advantageously includes an opening aligned with the opening of the impeller for the inflow of air therethrough.
    Type: Grant
    Filed: January 12, 1978
    Date of Patent: March 27, 1979
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Kurt Klundt
  • Patent number: 4144825
    Abstract: A device for the removal of flexible workpieces which are draped over a workpiece holding arm and which hang downwardly from each side thereof, in particular, over a work-handling arm of an arm-down sewing machine, comprises a horizontally disposed carrying arm or rod which is adapted to receive the sewn material and support it so that portions hang downwardly from each side thereof. A material engagement clip, which has a pair of clamping arms arranged below the carrying arm, is mounted for movement in directions substantially parallel to the carrying arm in order to move the clamping arms on respective sides of the workpiece and subsequently to move the clamping arms together so that they clamp the workpiece and strip the workpiece from the carrying arm when the clamping arms are moved outwardly from the carrying arm.
    Type: Grant
    Filed: October 27, 1977
    Date of Patent: March 20, 1979
    Assignee: Pfaff Industriemaschinen GmbH
    Inventors: Werner Angele, Hermann Welz
  • Patent number: 4143607
    Abstract: The sewing machine has a differential work transport, consisting of a lower main feed and lower and upper auxiliary feeds, with the step sizes of the auxiliary feeds being adjustable, from a step size substantially in accordance with the step size of the main feed, against spring bias. The step sizes are adjusted by respective setting devices having associated setting members connected, through a lever drive, to a common actuating device. The lever drive interconnecting the setting members of the setting devices for the lower and upper auxiliary feeds is operable to vary the step sizes of the lower and upper auxiliary feeds so that one of said lower and upper auxiliary feeds increases as the other of said lower and upper auxiliary feeds decreases. The transmission ratio of the lever drive is adjustable, and the lever drive includes a driver connection operative in one direction only.
    Type: Grant
    Filed: May 9, 1977
    Date of Patent: March 13, 1979
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Walter Hager
  • Patent number: 4140068
    Abstract: A material guiding device for feeding material to a stitch-forming area of a sewing machine which has a rail guide over which the material is placed for guiding movement from a charging point to the stitch-forming area, comprises a braking weight which has a bottom recess of a size to receive the rail guide with the material thereon so as to permit engagement of the weight over the material so as to move with the material during the feeding operation and to provide a braking action thereon. The construction includes a deflector adjacent the stitch-forming area which deflects the weight into a breaking weight return track in the form of a slide or chute which has an opening adjacent the stitch-forming area and is inclined downwardly to a delivery end which is remote from the stitch area at the charging point for the material so that a weight may be returned automatically to a place at which it may be applied to a material at the charging point.
    Type: Grant
    Filed: June 28, 1977
    Date of Patent: February 20, 1979
    Assignee: Pfaff Industriemaschinen GmbH
    Inventors: Hans W. Lux, Erich Willenbacher
  • Patent number: 4134346
    Abstract: A sewing machine for sewing buttonholes in a workpiece comprises a stationary lower part and an arm having one end pivotally mounted on the lower part and having an opposite end which carries a rotary hook which cooperates with a reciprocating needle carried in the lower part. The arm is pivotal relative to the base part to move the arm from a fixable sewing position with said hook spaced by a predetermined distance from the needle at a stitch-forming area to a rest position in which it is spaced away from the stitch-forming area. A thread-monitoring device is located adjacent the needle for monitoring the thread and detecting any breakage thereof. The machine includes a buttonhole cutting mechanism which is connected to the drive means so as to periodically cut the workpiece. A clamp is carried by the upper arm and it has a lower portion which rests on a resilient support which is biased upwardly by a spring.
    Type: Grant
    Filed: October 27, 1977
    Date of Patent: January 16, 1979
    Assignee: Firma Pfaff Industriemaschinen GmbH
    Inventors: Kurt Bolldorf, Walter Hager, Gunter Tolle
  • Patent number: 4126097
    Abstract: A sewing machine for the production of edge-parallel seams on layers of sewing material which includes a reciprocating needle which is movable through a stitch-forming station and a material feed for advancing the materials in a feeding direction through the station. The guide means for the material comprises a plurality of plates arranged in spaced vertical relationship one above the other and defining at least two separate material feed paths between adjacent plates. Each feed path has its own end guide or rule for the edge of the material which extends along a line extending laterally in a feeding direction through the needle axis. The construction includes an adjustable pressure member and a counterplate for applying and releasing pressure from materials being fed which is located at a spaced location from the end guides or rulers.
    Type: Grant
    Filed: June 1, 1977
    Date of Patent: November 21, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Erich Willenbacher
  • Patent number: 4122789
    Abstract: A sewing machine includes a housing having an oil pan portion defining an oil reservoir with a filter supported on a wall of the sewing machine housing in a position above the reservoir. A pump is employed to direct the lubricating oil upwardly through a pipe connection into the top of the filter and a portion of the oil which is pumped is circulated through a small size tube in a continuous manner such that it is deflected against a viewing glass at the top of the sewing machine and drops down into the operating mechanism contained in the sewing machine housing. In addition, a portion of the oil which is pumped into the filter passes through a removable filter cartridge and into the interior of the filter.
    Type: Grant
    Filed: December 7, 1977
    Date of Patent: October 31, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Kurt Klundt
  • Patent number: 4114546
    Abstract: A sewing machine for producing edge parallel seams in workpieces of any contour, includes a sewing machine needle which is reciprocated in a stitch forming area. A workpiece ruler guide extends laterally of the stitch forming area at an angle to a line passing through the needle axis. In addition, there is a workpiece guide mechanism which includes upper and lower guide plates forming a workpiece passage space therebetween which extends alongside the ruler. The upper plate is mounted over the lower plate for upward and downward movement relative to the lower plate and it includes a pressure point for applying a braking action on the workpiece which is effective when a tension member which is engageable with a pressure spring moves in a direction to stretch the pressure spring and increase the tension acting thereon and to urge the lower plate downwardly into engagement with the workpiece.
    Type: Grant
    Filed: October 31, 1977
    Date of Patent: September 19, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventors: Otto Kirch, Erich Willenbacher
  • Patent number: 4112859
    Abstract: An auxiliary sewing machine support table constructed for use with a sewing machine table having a sewing machine thereon with a reciprocating needle, with a surface which defines part of a means for feeding a workpiece in a feed direction. The auxiliary table is movable in a direction transverse to the feed direction and has a surface for carrying a remaining portion of the workpiece. The sewing machine table and the auxiliary table have trackway means defined therebetween which may be locked together by a clamping member carried on one of the tables which may be clamped to the other so as to lock a downwardly extending rail member on one table into an upwardly extending trackway on the other. The auxiliary table also includes controls for controlling the sewing machine from the auxiliary table.
    Type: Grant
    Filed: October 14, 1977
    Date of Patent: September 12, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Erich Willenbacher
  • Patent number: 4111139
    Abstract: A multineedle clamp for sewing machines, comprises a needle clamp body which has a plurality of spaced parallel needle receiving bores defined therein, with a web portion defined between each two adjacent bores. A pressing screw is threaded into the needle clamp body from one side and bears against a needle positioned in the adjacent needle receiving bore to bias it in a direction against the web. The needle receiving clamp body also includes a transverse bore extending into the body at substantially right angles to the pressing screw which carries a resilient pad member which is biased against the peripheries of two adjacent needles at the locations where the bores thereof are separated by the web and open into the laterally extending bore.
    Type: Grant
    Filed: February 2, 1977
    Date of Patent: September 5, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Kurt Klundt
  • Patent number: 4109334
    Abstract: The machine smoothes stitched seams on shoe shanks and applies a tape to cover the smoothed seam. A driven frictional wheel is cooperable with a second friction wheel rotatably mounted on a relatively elongated support over and along which the shanks are fed, the two friction wheels pressing and smoothing the stitched seams. Two holding elements are releasably engageable with this support at supporting points thereon spaced longitudinally of the support. A control circuit operates in such a manner that the two holding elements initially clamp the support at points spaced longitudinally therealong and, as a shoe shank leaves the friction wheels, the leading holding element is released for passage of the shoe shank therethrough while the trailing holding element remains clamped on the support. As the shoe shank clears the leading holding element, the latter is again clamped on the support and the trailing holding element is released from the support for passage of the shank.
    Type: Grant
    Filed: May 4, 1977
    Date of Patent: August 29, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventors: Heinrich Bungert, Herbert Wenz, Klaus Wentz
  • Patent number: 4098208
    Abstract: The sewing machine includes a reciprocating needle bar with a thread-engaging needle which cooperates with a rotatable looper carrying the looper thread which is driven by a rotatable looper drive shaft. The construction includes a thread knife and a thread clamp mounted adjacent the looper and a catcher mounted on a catcher shaft for rotation therewith selectively in the same direction of movement as the looper toward engagement with the knife and in an opposite return direction. The construction includes an improved control member for operating the catcher which is freely rotatable on the looper shaft and is axially displaceable therealong between an operative position and an inoperative position spaced axially from the operative position. A coupler is provided between the control member and the looper shaft which includes a driver having a rod portion which extends in a groove of the control member. A biasing spring biases the control member into an operative position.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: July 4, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Kristen Hedegaard
  • Patent number: 4088085
    Abstract: A sewing device for producing form seams is usable with a sewing machine having a needle which reiprocates in respect to a cooperating rotary hook. The sewing machine also includes a guide mechanism for guiding a workpiece along a path corresponding to the configuration of the form seam in respect to the needle. The device includes a workpiece support member having a stitch hole for the passage of the needle and a force-away surface bounding the stitch hole. The device includes a plate which is mounted so that the force-away surface is disposed between the needle and the rotary hook and it is mounted for vertical movement and horizontal oscillatory movement. The actuating means for the device causes a movement of the force-away surface in timed relationship to the reciprocation of the needle and in accordance with the movement of the workpiece in a direction opposite to the movement of the workpiece with respect to the needle and the rotary hook.
    Type: Grant
    Filed: February 2, 1977
    Date of Patent: May 9, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Walter Hager
  • Patent number: 4079685
    Abstract: A sewing machine, comprises a sewing machine head with a needle bar bushing supported in the head and a needle bar engaged in the bushing for upward and downward axial movement. The sewing machine includes an oil pan below the head and a scraping wick is engaged around the bar in the bushing and bears against a reabsorbing wick which extends from the scraping wick to the oil pan. The head is advantageously provided with a head cover which covers a recess having a pad which engages against the reabsorbing wick and biases it into contact with the scraping wick. In addition, the construction includes an additional wick which extends in an axial direction from a location above the scraping wick to a location at the lowermost end of the bushing and it is located between separated ends of the scraping wick and provides an oil-conducting connection with the scraping wick.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: March 21, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Kurt Klundt
  • Patent number: 4075954
    Abstract: A two-needle sewing machine includes a machine casing having a sewing head mounting the needles, a work support plate, and a ripping knife supported in the sewing head and working between the needles to form an elongated slot of a braid opening in a cut garment piece. A supporting bar is guided in the machine casing for longitudinal displacement perpendicular to the work support plate, and is rotatable into different angular positions. A single angular cross-section cutting knife is mounted on the supporting bar and serves as a tool for making diverging corner cuts at the opposite ends of the elongated slot. Air-operated piston-cylinder actuators are provided to rotate the supporting bar between two positions spaced angularly by 180.degree., and to displace the supporting bar longitudinally to effect the diverging corner cuts. The sewing head mounts a sliding foot arrangement for moving the work in a direction opposite to the normal work feeding direction.
    Type: Grant
    Filed: December 7, 1976
    Date of Patent: February 28, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventors: Peter Hintzen, Erich Willenbacher
  • Patent number: 4075960
    Abstract: A sewing machine includes a housing located below a reciprocating needle which contains two feed supports which are driven by operating mechanism so that they move through a substantially rectangular course of motion in their own plane. The feed supports include elongated members which extend through an opening in a front wall of a base of the sewing machine, and this wall is substantially closed against the outward splashing of oil by a first gasket which is engaged over the two support members which operate alongside each other and it is mounted so that it moves vertically to accommodate the vertical movement of the members. A second seal is effected by U-shaped sealing elements which engage over respective feed supports from respective opposite sides inwardly so that when the two supports are in alignment, the sealing members form a complete encirculing web.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: February 28, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventor: Kurt Klundt
  • Patent number: 4073252
    Abstract: A pocket stitch is sewn on cut workpiece parts which are guided into operative association with a reciprocating needle which effects a straight stitch when it is reciprocated and also may be swung from side to side to effect a zig-zag stitching. The workpiece is guided so as to form at least one substantially U-shape straight stitch having spaced apart leg portions and the stitch is secured by guiding the workpiece to effect the formation of a barring stitch at the ends of each leg portion by causing the needle to form a zig-zag stitch at such location. The sewing machine for sewing the pocket cuts includes a needle bar which may be swung during the operation of the drive mechanism or the zig-zag control mechanism may be shifted to effect the formation of a straight stitch. A rotatable cam which is driven by the drive mechanism positions a clamping plate having a substantially U-shape slot which permits reciprocation of the needle through a workpiece carried thereon.
    Type: Grant
    Filed: July 15, 1976
    Date of Patent: February 14, 1978
    Assignee: Pfaff Industriemaschinen GmbH
    Inventors: Reinhold Dobner, Walter Hager
  • Patent number: 4067276
    Abstract: The control device controls the sewing speed of a sewing needle automatically in a manner such that the temperature of the sewing needle, subjected to the influence of heat generated by friction with the material being sewn, does not exceed an adjustable predetermined value. Respective measuring members determine the temperature of the sewing needle and the temperature of a reference needle mounted at a location spaced from the sewing needle, and are connected to the input of a differential comparator circuit providing the differential voltage of the measuring members. A signal generator is operatively associated with the sewing needle and produces output pulses responsive to reciprocation of the sewing needle, to control connection of the output of the differential comparator circuit to the input of the sewing machine motor control. The reference needle is substantially identical with the sewing needle.
    Type: Grant
    Filed: October 15, 1976
    Date of Patent: January 10, 1978
    Assignees: Pfaff Industriemaschinen GmbH, Oskar Mohilo, Karl H. Kessler
    Inventors: Oskar Mohilo, Karl H. Kessler, Friedrich Wilhelm Stumpf