WO2001025519A1

WO2001025519A1 - Regulated airflow fabric for an air gravity conveyor

Info

Publication number: WO2001025519A1
Application number: PCT/US2000/027845
Authority: WO
Inventors: Gary B. Springer; John E. Hayes, Jr.
Original assignee: American Solid Woven Corporation
Priority date: 1999-10-06
Filing date: 2000-10-06
Publication date: 2001-04-12
Also published as: AU1075501A

Abstract

An improved weaving pattern for airflow fabric. The pattern uses gut construction (20) positioned between a pair of filler yarn (30) layers. Each filler yarn (30) layer is bound using a pair of warp yarns (40) that weave in opposite directions, much like a two sinusoidal functions that are 180° out of phase. With the high and medium porosity fabric, only a single binder yarn (50) surrounds the layers of filler yarn. In low porosity, a pair of binder yarns (50 and 52) are used, but the yarns are woven more like sinusoidal functions that are 90° out of phase.

Description

TITLE OF THE INVENTION

REGULATED AIRFLOW FABRIC FOR AN AIR GRAVITY CONVEYOR BACKGROUND OF THE INVENTION

1. Field of the Invention: The present invention relates to airflow fabrics that are used in air gravity conveyors; in particular, the present invention relates to an improved weaving pattern for an airflow fabric.

2. Discussion of Background:

Air gravity conveyors are useful in conveying granulated and powdered materials, such as concrete, flour, alumina, barite, and many other dry powders. A typical air gravity conveyor is illustrated in Fig. 1. The air gravity conveyor 200 comprises a hopper 204 that feeds the powdered material 202 onto an airflow fabric, which is enclosed within a chute 208. The airflow fabric separates the upper and lower plenum 210 and 212 of the chute 208 and extends the entire length of the chute 208. Pressurized air is introduced into the lower plenum through the air inlet 206, which is forced through the airflow fabric and flows into the upper plenum 210. Due to an incline of the airflow fabric in conjunction with the air flow, the powdered material 202 flows down the airflow fabric. The rate at which the powdered material 202 is conveyed can be regulated by the porosity and incline of the airflow fabric. Airflow fabric is constructed using various weaving patterns, depending upon the desired porosity. Prior art weaving patterns showing a high, medium and low porosity are illustrated in Figs. 2, 3, and 4, respectively. These weaving patterns have common characteristics: a plurality of filler yarn layers that are woven together by at least two binder yarns. With reference to the high porosity fabric illustrated in Fig. 2, a plurality of filler yarns 302 runs longitudinally the length of the fabric 300 and are held together by a pair of warp yarns 304, which are woven around the filler yarn 302 in a sinusoidal manner. The warp yarns 304 weave in opposite directions around the filler yarns 302, much like a two sinusoidal functions that are 180° out of phase. Three layers of the filler yarns 302, with surrounding warp yarn 304, are woven together using binder yarn 306. The binder yarn 306 is woven in the same manner as the warp yarn 304, much like a pair of sinusoidal functions that are 180° out of phase. As can be seen in Figs. 2 and 3, decreasing the porosity of the fabric 300 dramatically increases the number of filler yarns 302 and corresponding warp yarns 304. The weight of the resulting fabric substantially increases, while the fabric becomes less flexible. Unfortunately, the weaving patterns that are currently employed within the art require a relatively large amount of yam, which increases manufacturing time and the weight of the resulting fabric.

Therefore, there is a need for a weaving pattern for airflow fabrics that reduces the amount of yarn that is used, but can maintain a tight weave with low porosity. SUMMARY OF THE INVENTION

According to its major aspects and broadly stated, the present invention is an improved weaving pattern for airflow fabric. The pattern uses gut construction positioned between a pair of filler yam layers. Each filler yam layer is bound using a pair of warp yams that weave in opposite directions, much like a pair of sinusoidal functions that are 180° out of phase. With the high and medium porosity fabric, only a single binder yarn surrounds the layers of filler yam. In low porosity, a pair of binder yams are used, but the yams are woven more like sinusoidal functions that are 90° out of phase.

A major feature of the present invention is the weaving pattern, which uses a unique binder arrangement and gut construction. Instead of using a pair of binder yams, the present invention uses of a single binder yam to secure the filler yam. With the use of gut construction, the fabric reduces the layers of filler yarn needed. As a result, the total amount of yam needed for the fabric is reduced.

A major advantage of the present invention is the use of less yarn to manufacture the fabric. As a result, the manufacturing time to produce the fabric is also reduced. With fewer filler yarns, the fabric can be produce much more quickly and inexpensively.

Other features and advantages of the present invention will be apparent to those skilled in the art from a careful reading of the Detailed Description of a Preferred Embodiment presented below and accompanied by the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings,

Fig. 1 is a side view of a prior art air gravity conveyor with using an airflow fabric; Fig. 2 is a side cross-sectional view of a high porosity prior art airflow fabric; Fig. 3 is a side cross-sectional view of a medium porosity prior art airflow fabric; Fig. 4 is a side cross-sectional view of a low porosity prior art airflow fabric; Fig. 5 is a side cross-sectional view of a high porosity airflow fabric, according to a preferred embodiment of the present invention;

Fig. 6 is a side cross-sectional view of a medium porosity airflow fabric, according to a preferred embodiment of the present invention; and

Fig. 7 is a side cross-sectional view of a low porosity airflow fabric, according to a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Referring now to the figures, the present invention is an improved weaving pattern for airflow fabric. The weaving patterns showing a high, medium and low porosity are illustrated in Figs. 5, 6, and 7, respectively. For clarity, the fabric is illustrated with the yarns positioned in a spaced-apart manner. It is clear that the yam will be preferably woven to a tightness that is common in the industry. Although the patterns differ in porosity, each uses gut positioned between at least one pair of filler yarn layers. The binder yam position in each pattern also differs from the prior art. With the high and medium porosity fabric, only a single binder yam surrounds the layers of filler yam. In low porosity, a pair of binder yarns are used, but the yarns are woven more like sinusoidal functions that are 90° out of phase. In order to decrease porosity, additional layers of gut construction are added. Gut construction refers to a mesh that extends longitudinally the length of the fabric. Referring to Fig. 5, a fabric with high porosity construction is illustrated. A plurality of filler yarns 30 run longitudinally the length of the fabric 10 and are held together by a pair of warp yams 40, which are woven around filler yam 30 in a sinusoidal manner. Warp yams 40 weave in opposite directions around filler yams 30, much like a pair of sinusoidal functions that are 180° out of phase. Gut construction 20 is positioned between the two layers of filler yam 30. A single binder yam 50 is woven around the layers of filler yam

30 in a sinusoidal manner, such that the binder yam is wrapped around each filler yarn 30.

Referring to Fig. 6, a fabric with medium porosity construction is illustrated. Again, a plurality of filler yams 30 run longitudinally the length of the fabric 10 and are held together by a pair of warp yams 40, which are woven around filler yarn 30 in a sinusoidal manner like a pair of sinusoidal functions that are 180° out of phase. Gut construction 20 is positioned between the two layers of filler yam 30. In order to decrease porosity, the gut construction 20 is increased in thickness. Again, single binder yam 50 is woven around the layers of filler yam 30 in a sinusoidal manner, such that the binder yam is wrapped around each filler yam 30. As can be seen by a comparison with Fig. 3, the present invention uses much less yam to create the desired air flow characteristics.

Referring to Fig. 7, a fabric with low porosity construction is illustrated. Again, a plurality of filler yams 30 run longitudinally the length of the fabric 10 and are held together by a pair of warp yams 40, which are woven around filler yam 30 in a sinusoidal manner like a pair of sinusoidal functions that are 180° out of phase. Two layers of gut construction 20 are positioned between the three layers of filler yam 30. In order to decrease porosity, the gut construction 20 is increased in thickness. A first binder yam 50 and second binder yam 52 are woven around the layers of filler yam 30 in a sinusoidal manner, such that the pair of binder yams 50 and 52 are woven like a pair of sinusoidal functions that are 90° out of phase with each other.

It will be apparent to those skilled in the art that many changes and substitutions can be made to the preferred embodiment herein described without departing from the spirit and scope of the present invention.

Claims

WHAT IS CLAIMED IS:

1. An airflow fabric for use with an air gravity conveyor, said airflow fabric comprising: plural layers of filler yarns, each filler yam within each said layer of filler yarns being approximately parallel; warp means for securing adjacent filler yams within each said layer of filler yams; a layer of gut construction, said layer of gut constmction being positioned between each said layer of filler yams; and binder means for securing each said layer of filler yams together.

2. The airflow fabric as recited in claim 1, wherein said binder means comprises a binder yam that is woven around said layers of filler yams such that said binder yam reverses direction upon encountering each filler yam.

3. The airflow fabric as recited in claim 1, wherein said binder means consists of a single binder yam that is woven around said layers of filler yams.

4. The airflow fabric as recited in claim 1 , wherein said binder means comprises a pair of binder yarns that are woven around said layers of filler yarns in a sinusoidal manner that is 90° out of phase.

5. The airflow fabric as recited in claim 1, wherein said gut construction has a plurality of layers.

6. The airflow fabric as recited in claim 1 , wherein said plural layers of filler yams is two layers.

7. The airflow fabric as recited in claim 1 , wherein said warp means comprises a pair of warp yams that are woven around adjacent filler yams within each said layer of filler yams in a sinusoidal manner that is 180° out of phase.

8. An airflow fabric for use with an air gravity conveyor, said airflow fabric comprising: plural layers of filler yams, each filler yam within each said layer of filler yams being approximately parallel; warp means for securing adjacent filler yams within each said layer of filler yam; a layer of gut constmction, said layer of gut constmction being positioned between each said layer of filler yams; and a binder yam that is woven around said layers of filler yams such that said binder yam reverses direction upon encountering each filler yam.

9. The airflow fabric as recited in claim 8, wherein said binder yam consists of a single binder yarn.

10. The airflow fabric as recited in claim 8, wherein said binder yam is a pair of binder yarns that are woven around said layers of filler yams in a sinusoidal manner that is 90° out of phase.

11. The airflow fabric as recited in claim 8, wherein said gut constmction has a plurality of layers.

12. The airflow fabric as recited in claim 8, wherein said plural layers filler yarns is two layers.

13. The airflow fabric as recited in claim 8 , wherein said warp means comprises a pair of warp yams that are woven around adjacent filler yams within each said layer of filler yarns in a sinusoidal manner that is 180° out of phase.

14. An airflow fabric for use with an air gravity conveyor, said airflow fabric comprising: plural layers of filler yams, each filler yam within each said layer of filler yarns being approximately parallel; a pair of warp yarns that are woven around adjacent filler yams within each said layer of filler yarns in a sinusoidal manner that is 180° out of phase; a layer of gut construction, said layer of gut constmction being positioned between each said layer of filler yams; and binder means for securing each said layer of filler yarns together

15. The airflow fabric as recited in claim 14, wherein said binder means comprises a binder yam that is woven around said layers of filler yams such that said binder yam reverses direction upon encountering each filler yam.

16. The airflow fabric as recited in claim 14, wherein said binder means consists of a single binder yam that is woven around said layers of filler yams.

17. The airflow fabric as recited in claim 14, wherein said binder means is a pair of binder yams that are woven around said layers of filler yams in a sinusoidal manner that is 90° out of phase.

18. The airflow fabric as recited in claim 14, wherein said gut constmction has a plurality of layers.

19. The airflow fabric as recited in claim 14, wherein said plural layers filler yams is two layers.

20. The airflow fabric as recited in claim 14, wherein said warp means comprises a pair of warp yams that are woven around adjacent filler yams within each said layer of filler yarns in a sinusoidal manner that is 180° out of phase.