Claims
- 1. In a sewing machine comprising a bed, a loop taker rotating on a vertical axis within the bed, a fixed bobbin case rotation restraining member fastened to the bed, and a bobbin case contained within said loop taker, the bobbin case containing a bobbin carrying a supply of bobbin thread and having an outwardly facing wall containing a depression and an abutment surface located on the wall distant from the depression, the depression entrapping the fixed bobbin case rotation restraining member to prevent the bobbin case from partaking of rotation with the loop taker:
- an adjustable bobbin case retainer;
- a second rotation restraining member carried on the adjustable bobbin case retainer and cooperating with the fixed rotation restraining member to prevent rotation of the bobbin case, the adjustable bobbin case retainer comprising a base plate containing a first elongated slot and a second elongated slot near opposite extremities of the base plate, the slots being elongated in directions which are substantially perpendicular to each other;
- first means for pivotally fastening the base plate to the sewing machine bed through the first of the slots to pivot the second rotation restraining member toward and away from the abutment surface, the first slot being elongated in a direction substantially parallel to the abutment surface to allow movement of the retainer in a direction substantially parallel to the abutment surface;
- second means cooperating with and closely fitting against the sides of the second of the elongated slots for eccentrically adjusting the distance of the base plate relative to the loop taker, whereby the distance between the bobbin case and the second rotation restraining member carried on the base plate may be adjusted in a direction generally parallel to the direction of the abutment surface by the eccentric adjusting means and the pivotal fastening means; and
- third means cooperating with the second means and the sides of the second elongated slot to lock the rotation restraining member carried on the base plate at predetermined points at different perpendicular distances from the abutment surface.
- 2. The adjustable bobbin case retainer as set forth in claim 1 wherein the means for eccentrically adjusting the base plate comprises a stud having an eccentric portion that closely fits between the sides of the second elongated slot, the stud being fastened to the sewing machine bed, the eccentric portion passing through the second of the elongated slots for imparting movement to the base plate in the direction of elongation of the first slot when the stud is rotated.
- 3. The adjustable bobbin case retainer as set forth in claim 1 in which the third means comprises spring-biased means slidably mounted on the base plate to slide substantially parallel to the axis of the first slot, the spring-biased means comprising a bifurcated extremity to engage the eccentric adjusting means to lock the bobbin case retainer relative to the bobbin case and to allow movement of the retainer away from the bobbin case to effect removal of the bobbin case from the loop taker without disturbing the eccentric adjusting means.
- 4. A sewing machine comprising:
- a rotatable loop taker;
- a generally round bobbin case within the loop taker and comprising first and second generally radial, spaced surface portions;
- a fixed bobbin case rotation restraining member extending into a position adjacent the first surface portion of the bobbin case to prevent rotation of the bobbin case, but sufficiently spaced from the bobbin case to allow thread to pass between the fixed bobbin case rotation restraining member and the first surface portion;
- an adjustable bobbin case retainer comprising a base plate, a cushion spring mounted on the base plate and extending adjacent the second surface portion of the of the bobbin case to prevent rotational movement of the bobbin case, but spaced sufficiently from the second surface portion to permit thread to pass between the cushion spring and the second surface portion of the bobbin case;
- fixed support means for the loop taker, the fixed bobbin case rotation restraining member, and the adjustable bobbin case retainer;
- first pin and slot means comprising a first pin and a first slot connecting the support means and the adjustable bobbin case retainer, the slot means extending in a first direction to permit movement of the adjustable bobbin case retainer substantially parallel to the generally radial second surface portion and the support means in the first direction to vary the distance between the cushion spring and the bobbin case in that direction, the first pin having a circular portion of substantially the same diameter as the width of the first slot;
- second pin and slot means connecting the support means and the adjustable bobbin case retainer, the second pin and slot means comprising a second pin comprising an eccentric portion to control the relative position of the adjustable bobbin case retainer with respect to the support means by controlling the relative location of the first pin in the first slot by rotation of the eccentric portion of the second pin, and a second slot having a direction of elongation at an angle to the direction of the first slot, the eccentric portion of the second pin fitting slidably within a controlling part of the second slot to permit limited movement of the adjustable bobbin case retainer also in a second direction corresponding to the direction of elongation of the second slot when the eccentric portion of the second pin is embraced by the controlling part of the second slot; and
- slidable means mounted on the adjustable bobbin case retainer to move relatively perpendicularly with respect to the direction of elongation of the second slot to engage the pin in the second pin and slot means and fix the position of the adjustable bobbin case retainer during operation of the machine.
- 5. The invention as defined in claim 4 in which said first pin of said first pin and slot means is held in said support means, and in which said first slot is formed in said adjustable bobbin case retainer, the first slot being so oriented that, when the adjustable bobbin case retainer is in position with the first pin inserted through the first slot, the first slot extends generally parallel to a radial line between the bobbin case and the second surface portion of the bobbin case.
- 6. The invention as defined in claim 5 in which said second pin of said second pin and slot means is mounted in said support means, and in which said second slot is formed in said adjustable bobbin case retainer, the controlling part of the second slot extending substantially perpendicular to the first slot.
- 7. The invention as defined in claim 6 in which the eccentric pin comprises a first cylindrical portion rotatably held in the support means and a second cylindrical portion eccentrically offset with respect to the first portion and extending through the second slot, the second slot having an enlarged part large enough for the first cylindrical portion of the eccentric pin to fit therethrough.
Parent Case Info
This is a continuation-in-part of Ser. No. 004,117 filed Jan. 17, 1979, now abandoned.
US Referenced Citations (5)
Foreign Referenced Citations (2)
Number |
Date |
Country |
531095 |
Jul 1955 |
ITX |
52-74864 |
Jun 1977 |
JPX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
4117 |
Jan 1979 |
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