Sewing Machine Feed Systems
Common Sewing Machine Feed Systems
Manual feed or Free Motion or
Freehand or Darning Feed.
*Operator moves work under needle. Freehand motion.
*Machine may have a vertical motion foot that clamps the goods before the needle enters
the material, and releases to allow the operator to manipulate the goods between each
stitch.
*Darning, Embroidery, freehand Quilting, etc.
Feed dog.
*Mechanical bit with teeth or friction surface that transports or assists in the transport
of material. Conventionally referring to a bit in the bed of the machine below the goods
which transports material.
*Has a directional movement in which the material is fed.
*May lift upwards to capture material between itself and a presser.
-or-
*May not lift upwards but a presser may hold material down against the feed dog.
Drop feed or Regular Feed.
*Incorporates a feed dog.
*The most common feed system.
*Also called four-motion feed dog or four-motion drop feed.
*Motion includes a "drop" below the surface of the material. A movement toward
the position in which feed will begin. A "rise" into the material. Lastly, a
motion feeding the material.
Needle feed or Walking Needle
*Needle enters goods and remains in the goods while moving perpendicular to the needles'
normal direction of travel, thereby feeding the goods, or assisting in feeding the goods.
*Can assist in preventing upper, middle, and lower layers of material from slipping in
relation to each other.
*Does not necessarily require pressure against the planar surfaces of the material to
feed, and can be used where material should not be marked by the action of a feed dog
and/or upper feed.
*Is often used in conjunction with drop feed and/or with upper feed.
Upper pivot needle feed.
*The needle bar, which carries the needle, is held in a frame, and its motion is pivoted
from a point on the frame farthest from (or far from) the needle.
*The needle will enter the goods at a leading angle from the centerline of needle travel,
and will exit the goods at a trailing angle from the centerline of needle travel. In other
words, the needle enters the goods at a certain angle and exits at a different angle. This
would seem to disrupt the material and the stitching process, but in practice it does not.
Central pivot needle feed.
*The needle bar, which carries the needle, is held in a frame, and its motion is pivoted
from a point near the middle of the frame.
*The needle will enter the goods at a greater leading angle from the centerline of needle
travel than with the upper pivot system described above, and will exit the goods at an
equally great trailing angle from the centerline of needle travel that it entered with. In
other words, the needle enters the goods at a certain angle and exits at a different
angle. This would seem to disrupt the material and the stitching process, but in practice
it does not, except with thicker or heavier goods.
*There is less momentum of the needle bar frame in motion than with the upper pivot
system, and higher stitching speeds can be reached.
Parallel drive needle feed.
*The needle bar, which carries the needle, is held in a frame, and its motion is always
parallel in relation to its prior and successive movements. It remains perpendicular to
the material at all times. For example, if the needle enters the goods at 90 degrees to
the materials' surface, the needle will remain at 90 degrees through its travel, and will
exit at the same 90 degree angle.
*It is the type of needle feed suitable for stitching the heaviest and thickest of
materials.
*The mechanism involved in a parallel drive makes for a more expensive unit and will
generally have a slower stitching speed.
Wheel feed.
*A rotary wheel with a movement in the direction of feed.
*Incorporates a friction surface or clamping surface that feeds or assists in feeding the
goods.
*Has either an intermittent motion or a continuous motion.
*Continuous motion wheel feed must work in unison with a needle feed.
Upper feed.
*Mechanical foot or bit, with teeth or friction surface or a smooth surface, that
transports or assists in the transport of material. Often a foot working in unison with a
drop feed.
*Has a directional movement in which the material is fed.
*May push downwards into the material to capture material between itself and another feed
component or against the bed or a plate on the bed.
Vibrating presser foot.
*A foot with teeth or friction surface or a smooth surface, that transports or
assists in the transport of material.
*Has a vibrating motion forward with the feeding process and backward with the return
stroke.
*Is the only top foot or is paired with a presser foot.
*Usually incorporates a lifting motion with the backward stroke. This allows the foot to
clear the material and to drop relatively straight down onto any raised or uneven portion
of the material without interference.
*Commonly called a walking foot, feeding foot, or top feed.
Alternating presser feet.
*A pair of feet that alternately press against the material. While one foot is
pressing against or feeding the material, the other foot is raised clear of the material.
The positions then alternate.
*One foot is typically a vibrating presser foot while the other foot is typically a rising
and descending presser foot. The vibrating foot will feed or assist in feeding while the
rising and descending foot will hold the material down between feeding motions.
*The rising and descending foot is often called a lifting presser foot.
Top feed.
*Any type of upper feed.
Jump foot.
*A vibrating presser foot whose forward and backward motions are not driven, but
spring loaded.
*will usually incorporate a lifting motion on the return stroke.
Walking foot.
*A vibrating presser foot with a lifting motion on the backward (return) stroke.
*Often part of an alternating presser foot assembly and commonly used in conjunction with
compound feed or a drop feed.
Spring action walking foot.
*Same as jump foot.
Driven walking foot
*A vibrating presser foot whose forward (feeding) motion only or both forward and
return motions are driven by a direct connection to linkage.
Wheel feed.
*A rotary wheel with a movement in the direction of feed.
*Incorporates a friction surface or clamping surface that feeds or assists in feeding the
goods.
*Has either an intermittent motion or a continuous motion.
*Continuous motion wheel feed must work in unison with a needle feed.
Reverse feed.
*The ability to feed material opposite of a machines' normal direction of feed.
*The reverse stitch length may be capable of providing as long of a stitch length as the
forward feed does, or it may be limited to providing an average reverse stitch length or a
maximum reverse stitch length shorter than the forward feed stitch length.
*The ability of the reverse feed to feed material may be equal to or less than the ability
of the forward feed to feed material.
Clamp feed.
*A clamp or clamps from above the material and pressing downward, effectively
holding the material between itself and the machine bed or a clamp or clamps above and
below the material, holding the material firmly between the upper and lower clamps.
*The clamp or clamp set is driven by linkage.
*The linkage moves the clamp and material under the needle as the stitches are being
formed.
*The movement of the clamp and material can be in any direction or follow any pattern
provided for in the linkage drive mechanism.
Puller feed.
*Usually accomplished by feed rolls; "rollers".
*Material passes between rolls, between upper roll and bed, or between lower roll and
presser foot.
*A feed roll is mechanically driven to transport the material.
*Where material passes between two rolls, the second roll may also be driven.
*Commonly used in association with any other feed system.
*Generally suitable for straight runs or large radius curves only.
Combination feeds.
Upper and lower feed.
*A combination of any upper feed system and a feed dog or drop feed.
*The term "walking foot" (see "Upper feed" heading above) is often
used to mean a vibrating presser foot in combination with compound feed, or in conjunction
with a drop feed.
Compound feed.
*A combination of needle feed and drop feed.
*The term is often used erroneously to indicate any combination of feed systems.
Other combination feeds.
*Any combination of feed systems, within current engineering ability, may be
utilized.
Unison feed.
*This term is used in two different ways.
*One usage of this term is its application to any of two or more feed systems working in
combination.
*A second usage of this term is to describe the uncommon feed system of a vibrating
presser foot or alternating presser feet, along with needle feed, and a drop feed or feed
dog, working in combination, but operating from a one-piece frame. The frame extends from
the presser foot/needle feed mechanism, through the machine casting, to the drop feed/feed
dog. This is the only system, when in good repair, where it is impossible for the upper
and lower feed mechanisms to become out of synchronization. All other feed systems are
synchronized by linkage or by electronic control.
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