US 4,658,144 A · System for alignment and feeding cooperating fabric parts in sewing operations

Abstract

Apparatus to align a plurality of objects while being concomitantly transported via a drive mechanism. Included is a detectional device at fixed locations in the path of transport to determine the relative actual positions of the objects and comparing the determined positions with a relative position to be maintained. On the basis of the comparison, the positional detection means emits a correction signal for operating a repositioning mechanism which imposes a restraining force on the leading of the objects that restrains the object in opposition to the transport force imposed thereon by the drive mechanism. For generating the emitted correction signal there is included circuit means including an encoder for generating pulses and means to determine the quantity of pulses corresponding to the variance between the compared portions of the objects. This enables high resolution monitoring to be effected whereby the restraining force imposed against the object can either be proportional to the magnitude of the correction signal or can be a fixed force applied by the repositioning mechanism for a proportioned time interval.

Claims31

Dependent claims

An apparatus to align a plurality of objects comprising:

transport means for moving the objects concomitantly over a predetermined path;
positional detection means located along the path for determining the actual relative positions of the objects and comparing the determined relative position to a predetermined relative position to be maintained;
said positional detection means being operable to provide an alignment correction signal correlated to the differential between said determined actual relative position and said relative position of the objects to be maintained;
and
repositioning means receiving the provided signal from said positional detection means and operable in response to receipt thereof for imposing a controlled resistance to the movement of at least one object along said path by said transport means.

2 more elements

An apparatus for aligning end portions of two pieces of fabric as the fabrics are being sewn together at a sewing station, the apparatus comprising:

transport means for moving the pieces of fabric along a predetermined path toward said sewing station;
positional detection means for providing a plurality of position signals, each indicating the position of the end portion of the respective fabric pieces as the end portions of the fabric pieces travel across specific locations along the predetermined path;
reference pulse means connected to the transport means for providing reference pulses indicating the fabric travel along the path;
offset circuit means connected to the reference means and the positional detection means for providing a positional difference signal indicating a relative positional difference between the end portions of the fabric pieces and which has a magnitude related to the difference between the actual relative positional difference and a predetermined relative positional difference value to be maintained;
and
alignment means operable in opposition to the fabric movement effected by said transport means for receiving said positional difference signal and restraining the travel of at least one of the pieces of fabric along the path in response to the positional difference signal thereby aligning the end portions of the two pieces of fabric as they travel along the path.

3 more elements

Dependencies are inferred from the claim text.

System for alignment and feeding cooperating fabric parts in sewing operations

Life of this patent

System for alignment and feeding cooperating fabric parts in sewing operations

Life of this patent

Abstract

Claims31