|Publication number||US3863368 A|
|Publication date||Feb 4, 1975|
|Filing date||Apr 24, 1972|
|Priority date||Apr 24, 1972|
|Publication number||US 3863368 A, US 3863368A, US-A-3863368, US3863368 A, US3863368A|
|Original Assignee||Vasilantone Michael|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (5), Referenced by (6), Classifications (10)|
|External Links: USPTO, USPTO Assignment, Espacenet|
United States Patent. 1191 Vasilantone EXPANDER, DEVICE FOR STRETCHING A FABRIC SHEET  Inventor: Michael Vasilantone, 147 E. First Ave., Roselle, NJ.
 Filed: Apr. 24, 1972  Appl. No.1 246,697
152 US. c1. 38/1025, 38/102.91
 Int. Cl. D06c 3/08  Field of Search 26/54; 38/1025, 102.6, 38/102.91; 160/374, 374.1
 References Cited UNITED STATES PATENTS 249.552 11/1881 Seitz 1. 160/374 2,752.630 7/1956 Taylor. 26/54 X 3,359,663 12/1967 Black 38/1029] 14 1] Feb. 4, 1975 12/1969 Hamu 3,482,343 I 3,601,912 8/1971 13111163 38/l02.91 FOREIGN PATENTS OR APPLICATIONS. 36,150 7/1886 Germany 38/1026 40,666 9/1887 Germany 38/1025 Primary Examiner-Robert R. Mackey Attorney, Agent, or FirmJohn J. Byrne; Edward E. Dyson  ABSTRACT An ekpander device for stretching a fabric sheet comprising linkage assemblies which expand and contract in response to the input of a drive means. Fabric gripping elements are connected to the linkage assembly 'and move linearly as said linkage expands and contracts.
6 Claims, 7 Drawing Figures PATENTED FEB 41975 SHEET 10F 3 PATENTEDFEB' M915 3. 863.368 sum 30F 3 EXPANDER, DEVICE FOR STRETCI-IING A FABRIC SHEET This invention relates to an expander and, in particular, an expander for stretching flexible sheets such as textile fabrics in a plurality of different directions simultaneously and equally.
Fabric stretchers per se are not new to the prior art;; however, the prior artdevices are generally unsatisfactory to the extent that they are unable to maintain uniformity and stability in the fabric during the stretching operation. The result is that the non-uniformly stretched fabrics may present soft spots". A particular application for an expander device of the type disclosed herein is in stretching fabric used as stencil screens in screen printing processes. The expanderof this invention is used to stretch the fabric uniformly after which a frame is placed on the fabric and the fabric is attached thereto by any conventional means. The expander then releases the material but that portion attached to the frame remains taut and wrinkled free. Of course, the invention is not limited to the assembly of stencil screen frames. I
Accordingly, it is an objective of this invention to provide an expander device for uniformly stretching a flexible sheet material such as a textile fabric in a plurality of different directions equally and simultaneously.
It is a further objective of this invention to provide an expander apparatus which is operable by a single drive means.
It is a further objective of this invention to provide an to the following detailed description when viewed in the light of the accompanying drawings wherein:
FIG. 1 is a perspective view of the expander of this invention, having thereon a fabric to be stretched;
FIG. 2 is a plan view of the device of FIG. 1;
FIG. 3 is a view taken on line 33 of FIG. 2;
.FIG. 4 is an exploded view of one of the driving posts of this invention;
FIG. 5 is a view taken on line 5-5 of FIG. 3;
FIG. 6 is an exploded view of a fabric gripping element; and
; FIG. 7 is a cross sectional view taken on line 7-7 of FIG. 1.
Referring now to FIG. I, the expander apparatus of this invention is generally indicated by the numeral 10 and includes four, equally, radially spaced fabric gripping elements 12 which are mounted on a framework generally indicated by numeral 14 for uniform and simultaneous reciprocatory movement in the direction of the arrows.
The mechanism by which the elements 12 are shifted is more fully understood with reference to FIGS. 2 and 3. The expander is attached to any suitable base 16 by means of mounting pins or any other suitable mounting means 18. The framework 14 consists ofa pair of vertically spaced plates 20a and 20b. The plates are supported by the mounting pins 18 each of which includes an annular flange on which maybe threaded nut or the expander apparatus which is readily adjustable to accommodate fabric panels of different sizes.
It is a further objective of this invention to provide an expander apparatus which exerts great stretching forces relative to the level of force input.
More particularly, it is an objective of this invention to provide an expander device for stretching fabrics comprising a framework, and fabric gripping expander elements mounted on the framework for reciprocatory movement in an outward radial direction relative to the center of the framework. Guide means are provided in the framework for guiding the elements in their outward movement. The'means for moving the elements comprises an expandible linkage system connecting each of said elements, and drive means for expanding the linkage system thereby reciprocating said elements outwardly simultaneously and equally. In a preferred embodiment, the drive means is a threaded, rotatable shaft having axially spaced, oppositely threaded positions thereon, threadedly received in nuts mounted at spaced points on said linkage means whereby said nuts are caused to move toward and away from each other upon rotation of the threaded shaft to contract and expand said linkage means. The linkage means in the preferred embodiment comprises two linkage assemblies each having first and second linkage sections. Each of the sections comprises four elongated bars of equal length pivotally connected to each other and normally assuming a rhombus shape when in place on saidframework. The second section of each of said assemblies overlies the first section with its major axis extending transversely to the major axis of the first section. Connecting means are provided for loosely joining the sections at their points of overlap.
These and other objects of the invention will become more apparent to those skilled in the art by reference 'like 22 for abutting the undersurface of the plate 20b.
A spacer sleeve 24 is mounted on each of the pins and supports the upper plate 20a in spaced relationship relative'to the lower plate 20b. Each'of the mounting pins is headed at 26 whereby the plates are securely held in spaced relationship. The plates are identical in construction and, as best seen in FIG. 3, include a plurality of radially disposed guide slots 28. A pair of linkage assemblies generally indicated by the numerals 30a and 30b are positioned adjacent plates 20a and 20b. The linkage assemblies are identical, therefore, only one 300 will be described in detail, and can best be understood with reference to FIGS. 2 and 3. The linkage assembly 30a consists of first and second linkage sections 32a and 34a. The linkage sections are identical and each comprises four elongated metal bars or straps 36a and 38a, respectively. The straps of the respective upper and lower linkage sections 30a and 30b are joined together at their outer ends in a pivotal connection by means of pins 40 and 42 respectively, to each form a polygon which, as shown in FIG. 3, normally assumes the shape of a rhombus when in place on the framework 14. The section 34a underlies the section 32a and is angularly oriented relative to section 32a such that the major axis of section 34a extends transversely of the major axis of the section 32a.
v the respective pivotal connection. It can be seen that by means of these pivot pins and by means of the aligned slots in plates 20a and 20b of the framework, when the 3 lower linkage assembly is moved radially inwardly and outwardly in the slots, the upper linkage assembly movesin an identical manner.
The linkage sections of the respective linkage assemblies a and 30b are connected together at their points of intersection by means of connector posts 44 which are best shown in FIGS. 4 and 5. The posts 44 comprise a pair of cooperating side members 46 and 48 which when placed together define upper and lower strap receiving slots 50 and 52, respectively. The width of the slots 50 and 52 is sufficient to'permit the maximum amount of relative pivotal movement between the superposed straps as defined by the amount of movement permitted by guide slots 28. The posts ride in guide slots 29 which are disposed between the guide slots 28. The side members 46 and 48 are held together by means of locking elements 54 and 56 on the upper and 'lower ends thereof, respectively. Additionally, tension springs 58 and 60 are looped over the upper and lower ends of the members 46 and 48 and further help hold the sections together while permitting expansion,
within the limits permitted by the slots 62 and 64 in the locking members 54 and.56, respectively.
Drive means in the form ofa threaded shaft 66 is rotatably journalled in blocks 68 and 70 disposed between the upper and lower plates 20a and 20b. The blocks permit rotational movement of the shaft but prevent axial movement thereof. The shaft has right-and left-hand threaded sections 72 and 74 disposed on either side of the center point of the framework. First and second nuts 76and 78 are fixedly connected to a pair of diametrically opposed connector post 44 and threadedly receive thethreaded portions 72 and 74' of the shaft 66. The shaft is provided with a crank handle 80 to enable manual rotation thereof. It can be seen that as the shaft is rotated by means of the crank 80, the posts 44 to which the nuts 76 and 78 are attached will move toward or away from each other depending on the direction of rotation of the shaft. The movement of the posts is transmitted by means of the straps of the linkage section to those posts which are not connected to the nut to effect an equal and simultaneous movement of those posts. In other words, the linkage sections of the linkage assemblies will contract and expand equally within the limits defined by the guide slots in the upper and lower plates 20a and 20bof theframework 14. It is to be understood that power means can be utilized to drive the threaded shaft 66 in lieu of the crank handle 80.
Gripping elements generally indicated by the nu-' meral 12 are mounted on the outer end of the T-shaped elongated rods 84 which are mounted to the posts 44 by welding or other suitable means, and are equally radially spaced from each other. The gripping elements 12 as best seen in FIG. 6 and FIG. 7 each comprise a pair of L-shaped supporting bars 86 telescopically mounted on the outer ends of rods 84. The L-shaped bars 86 support an elongated channel member 88 on their upper ends and further receive a locking channel member 90 with both the members 88 and 90 being affixed to the brackets 86 by means of pin fasteners 92 or the like. The channel member 90 along with the member 88 defines an inverted channel 94 which receives an elongated locking tube 96 for frictionally clamping fabric 98 between the outer surface of the locking tube 96, the inner surface of the channel member 90 and the outer surface of the member 88. The
locking tube 96 is preferably coated with a friction surface 100 such as rubber or other elastomeric gripping material.
In operation, it can be seen that a panel to be stretched is placed over the expander apparatus 10 and the edges thereof are locked in the gripping elements 12 by means of the locking tube 96 and the channel member 90 as described above. The linkage assemblies 32a and 34a will, of course, be in their collapsed position or in other words, in the position wherein the pins and posts are at the inner ends of the guide slots 28 and departing from the principle of the present invention as comprehended within the .scope of the accompanying claims.
1. An expander device for stretching fabrics comprising a framework, a linkage system on said framework comprising a pair of parallelogram linkage sections each having major and minor axes, each parallelogram linkage section comprising bars connected to each other for relative pivotal movement, said sections being vertically stacked and angularly disposed relative to each other such that the major axis of one of said sec tions extends generally transversely to the major axis of the other, said stacked sections defining pointsof overlap, said framework including a plurality of radially extending guide means slidably mounted therein, the bars of overlapped linkage sections engaging with said guide means at said points of overlap, fabric gripper elements mounted for movement with said guide means and extending outwardly therefrom, drive means operably connected to a single opposed pair of guide means for expanding and contracting said linkage system, said guide means providing for controlled uniform and simultaneous movement ofsaid gripper elements toward and away from the center of said framework,
2. The expander of claim 1 wherein said drive means comprises a threaded rotatable shaft, and nut means on said opposed pair of guide means for threadedly receiving said shaft.
3. The expander of claim 1 and including a second pair of linkage sections of identical construction with the first pair of linkage sections and vertically spaced relative to the first pair, and a plate disposed between said vertically stacked pairs of sections, and wherein said guidemeans connect said pairs of sections at said 3,863,368 5 6 channel therein extending perpendicular to the direcchannel. I tion of movement of said gripper elements, and an 6. The expander device of claim 1 wherein said elongated locking bar snuggly received in the channel framework comprises a plate having radially extending of said member and clamping the edges of a fabric to slots therein. be stretched between said bar and the walls of said 5 I
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US249552 *||Dec 13, 1880||Nov 15, 1881||Ptters|
|US2752630 *||May 27, 1952||Jul 3, 1956||Wingfoot Corp||Film tensilizer|
|US3359663 *||Feb 23, 1967||Dec 26, 1967||Black James A||Stencil screen frame|
|US3482343 *||Jan 22, 1968||Dec 9, 1969||Hamu Kaino J||Frame for stressing sheet material|
|US3601912 *||Oct 25, 1968||Aug 31, 1971||Dubbs Wendell P||Woven screen stretching frame|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US5390596 *||Jan 6, 1992||Feb 21, 1995||Farr; Gregory C.||Stretching system for flexible planar materials|
|US5819654 *||Aug 22, 1996||Oct 13, 1998||Farr; Gregory Charles||Stretching system for flexible planar materials|
|US6138592 *||Jan 4, 1999||Oct 31, 2000||Seneff; Robert W.||Apparatus for applying frames to fabric|
|US9322506 *||Mar 2, 2011||Apr 26, 2016||Flexsys, Inc.||Compliant motion distribution system|
|US20110253957 *||Mar 2, 2011||Oct 20, 2011||Ervin Gregory F||Compliant motion distribution system|
|WO1996025239A1||Feb 17, 1995||Aug 22, 1996||Farr, Gregory, C.||Stretching system for flexible planar materials|
|U.S. Classification||38/102.5, 38/102.91|
|International Classification||D06C3/00, D06F59/00, D06C3/08, D06F59/08|
|Cooperative Classification||D06C3/08, D06F59/08|
|European Classification||D06C3/08, D06F59/08|