Sheet-material associating – Reciprocating-carriage piler
Reexamination Certificate
1999-06-22
2001-06-05
Ellis, Christopher P. (Department: 3651)
Sheet-material associating
Reciprocating-carriage piler
C270S039010, C270S039080, C493S444000, C493S413000, C493S458000, C493S937000, C493S938000
Reexamination Certificate
active
06241232
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to an apparatus for folding a textile fabric length with at least two transport belts which can be driven in opposite directions, wherein a gap is disposed between the transport belts, through which gap the fabric length can be drawn while forming a fold when the transport belts are driven in opposite directions. The invention also relates to a method for operating the apparatus.
BACKGROUND OF THE INVENTION
Apparatus of this type are used, for example, although by no means exclusively, for folding bed sheets so that these can be packed ready for sale after having been sewn. Such apparatus comprise at least two transport belts which can be driven in opposite directions and are disposed such that a gap is produced between them. In order to fold the fabric length, this is laid out on the transport belts, coming to lie above the gap between the transport belts. The fabric length is drawn into the gap through the two transport belts being driven in opposite directions, so that the fabric length is folded once. More than two transport belts may be disposed one behind the other, depending on the number of times the fabric length has to be folded, with each two transport belts forming a gap for folding the fabric length. The fabric lengths can thus be folded several times in succession by driving the various transport belts accordingly.
The disadvantage of the known apparatus lies in the fact that relatively large tolerances of the alignment of the individual fabric layers occur when folding the fabric lengths. A particular result of this is that, instead of the lateral edges of the fabric lengths coming to lie in an optimum parallel position on top of one another following folding, an angular offset starting from the folding edge occurs between the lateral edges. Errors of this kind in the alignment of the edges are particularly detrimental when the fabric length is folded several times, as folding errors increase in subsequent folding stages.
SUMMARY AND OBJECTS OF THE INVENTION
The primary object of the present invention is to provide an apparatus with which textile fabric lengths can be folded more accurately. A further object of the present invention is to provide a method for operating the apparatus according to the invention.
According to the invention, an apparatus is provided for folding a textile fabric length, with at least two transport belts which can be driven in opposite directions. A gap is disposed between the transport belts, through which gap the fabric length can be drawn while forming a fold when the transport belts are driven in opposite directions. A gripping member is disposed above the two transport belts, which member can move substantially parallel to the upper side of the transport belts. This gripping member can be brought to lie between the front and the back end of the unfolded fabric length with a fixing action. After the gripping member has been fixed in the central region of the fabric length, it is moved parallel to the upper side of the transport belts. The fabric length is as a result folded for the first time. In this case the folding edge extends along the contact points or contact line between the gripping member and the fabric length. After the gripping member has been moved laterally up to an end point, the fabric length comes to lie in two superimposed layers on the transport belts. After the gripping member has been disengaged from the fabric length, the latter can be folded again in the conventional manner by driving the transport belts accordingly.
The unfolded fabric length can in principle be fed to the apparatus in any desired manner before the gripping member is fixed. According to a preferred embodiment of the invention, the apparatus comprises a feed device by means of which the unfolded fabric length can be fed in a freely suspended manner, at least in certain regions, into the region at the side of the transport belts. The freely suspended feed of the fabric length enables the latter to be aligned in optimum fashion and, in particular, without creases, before the gripping member is fixed. As the fabric length hangs smoothly under its own weight, there cannot be any unwanted displacement of individual regions of the fabric length relative to one another.
It is particularly easy to form the feed device like a conveyor belt whose end which points towards the apparatus is disposed at least a little above the apparatus and at least at a short lateral distance from the latter. The fabric length is laid out flat on this conveyor belt. The conveyor belt is then driven such that the front edge of the fabric length is conveyed further in the direction of the apparatus and, upon reaching the end of the conveyor belt, hangs down between the latter and the apparatus. The fabric length is then conveyed further on the conveyor belt until the desired folding edge region of the fabric length and the gripping member lie opposite one another. The fabric length can subsequently be folded as desired through the use according to the invention of the gripping member.
According to a preferred embodiment of the invention, a mobile pushing mechanism is disposed below the feed device, which pushing mechanism can be brought to lie on the side of the unfolded fabric length which points away from the apparatus. The fabric length can be brought to lie against the gripping member by moving the pushing mechanism, so that the gripping member can be securely fixed to the fabric length.
It is of particular advantage if the shape of the edge of the unfolded fabric length at the front end can be influenced by the design and/or direction of movement of the part of the mobile pushing mechanism which can be brought to lie against the unfolded fabric length. For this purpose, for example, projecting regions may be molded on in the outer region of a contact edge of a pushing mechanism which comes to lie against the fabric, so that the corners of the unfolded fabric length at the front edge are raised slightly when the contact edge lies against the fabric length. This raising action can prevent the corners from jutting out after the folding operation has been completed.
According to a preferred embodiment of the invention, at least one measuring member is disposed below the feed device, by means of which member the vertical distance between the front end of the fabric length and the gripping member can be determined. By evaluating the signals from the measuring member, the drive of the feed device can be precisely controlled such that the region of the desired folding edge at the unfolded fabric length is disposed exactly opposite the gripping member.
According to a preferred embodiment, the measuring member is formed like a light barrier. A signal can be delivered as soon as the front end of the fabric length is conveyed into the region of the light barrier, so that the feed device is stopped either immediately or at the end of a certain after-running time.
The invention also relates to a method for folding a fabric length with the use of an apparatus according to the invention. The fabric length is fed laterally to the transport belts in a freely suspended manner in a first method step. The gripping member is then brought to lie against the unfolded fabric length between the front and the back end of the fabric length with a fixing action. The gripping member is subsequently moved laterally up to an end point while forming a fabric length which is folded once and lies in two layers, at least in certain regions. Once the end point has been reached, the gripping member is disengaged from the fabric length, so that the folded fabric length comes to lie on the transport belts. Finally, the fabric length, having already been folded once, is folded again by operating the transport belts in the conventional manner.
According to an advantageous development of the method according to the invention, after reaching the end point and before the fabric length is disengaged, the gripping member is moved in the opposite direction while formin
Henze Siegfried
Schmitt Hermann
Ellis Christopher P.
Mackey Patrick
McGlew & Tuttle P.C.
Texpa Maschinenbau GmbH & Co.
LandOfFree
Apparatus and method for folding a textile fabric length does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for folding a textile fabric length, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for folding a textile fabric length will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2483439