Patent Application
20250194787
The present invention relates to a system that cycles brushes on a tenter frame system. When the bristles of first brush becomes engorged with latex, the system can move the engorged brush out of the way and move a fresh brush into operation. An operator may remotely replace the engorged brush with another fresh brush without stopping the tenter line.
A tenter line uses a tenter frame to stretch a fabric, such as a carpet, along its sides while the length of the fabric is drawn through a device that heats or otherwise treats the fabric, such as an oven.
In some tenter frames, tenter chains with pins are used to stretch the fabric from side to side with a tenter chain on each side of the tenter frame. The pins are attached to an endless chain that pierce the selvage on each side of the fabric as it is fed into the frame to stretch it from side to side. The pins are withdrawn after the fabric leaves the treating device and reaches the end of the tenter line.
In some embodiments, the fabric may be a tufted carpet where a latex is added to the back of the carpet to secure the backstitching of the tufts in place. This specification will use an exemplary embodiment of a carpet, while those of skill in the art will understand that the inventions disclosed and taught herein are not limited to only that embodiment.
To firmly press the pins through the selvage and hold it in place, circular brushes with stiff bristles press against the selvage on the sides of the fabric as the fabric is entering the tenter frame. In many cases, the fabric has previously been coated with a substance, such as a latex, that is to be cured by heating the coated fabric. In these cases, the tenter frame may run through an oven so that it may convey they fabric through the oven.
The applied latex has been known to accumulate on the bristles of the brushes. Accumulated latex on the bristles has been known to lessen the usefulness of the brushes and in some cases may even bend the pins.
When brushes of prior art systems become engorged with latex, the entire line of prior art systems has had to be stopped while the brushes are replaced. This line stoppage is costly due to production delays, and requires substantial safety precautions so that operators are not placed in any danger during the operation of replacing unusable brushes.
For this reason, there is a need to automate the replacement of the brushes.
To this aim, the invention relates to a system that allows an operator to replace a circular brush used to press the selvage of a fabric onto a pin chain without stopping the tenter line or entering an area near the tenter line.
In a first independent aspect, the invention relates to an automated brush replacement device, comprising: a base plate comprising a plurality of posts, wherein each post is configured to releasably secure a circular brush; and a motor configured to rotate the base plate.
In a second independent aspect, the invention relates to a method of changing a circular brush on a tenter line, comprising: supplying a base plate configured with a plurality of circular brushes releasably secured to posts; wherein the posts are secured to and radially spaced apart and proximal an outer edge of the base plate; wherein a first post of the plurality of posts is configured with a first circular brush; and wherein the base plate is oriented in a first position such that the first post is located proximal a pin chain of the tenter line; rotating the base plate to a second position such that a second post is located proximal the pin chain of the tenter line.
Descriptions of these inventions will be defined in the appended independent claims, while preferred embodiments are defined in the dependent claims.
With the intention of better showing the characteristics of the invention, herein after, as an example without any limitative character, some preferred embodiments are described, with reference to the accompanying drawings, wherein:
Applicant has devised a system that will automatically replace brushes on a tenter system. In a preferred embodiment, an operator of the tenter line may activate the system to cycle the system so that when an engorged brush is taken out of service, a fresh brush is simultaneously placed in service. In this embodiment, the tenter line does not need to be stopped or even slowed.
In another embodiment, the system may be fully automated so that an operator need not be present to activate the system. In this, means for detecting when a brush is not performing within desired parameters may automatically activate the system to replace an engorged brush with a fresh brush. The performance parameters may include, but are not limited to: measuring the weight of the brush which indicates that the brush has been laden with too much latex; measuring the rotation of the brush which indicates a latex laden brush is not keeping up with the progression of the fabric entering the tenter line; or other indicators that may be known to those of ordinary skill in the art.
The illustrative embodiment of
Those of skill in the art will know how to configure an automated brush replacement device as disclosed and taught herein where a base plate is not vertically oriented but such that the posts 134a-d will position the brushes 130a-d at a desired location and orientation relative to the pin chain 120. If the brushes used have a known diameter, the posts may be centered on the base plate to position the brushes at a desired distance from the pin chain. That is to say that by configuring the post to be a specific distance from the pin chain, the bristles of a brush may be positioned to push down with a desired pressure on the selvage to ensure that the selvage stays pierced and in place on the pins of the pin chain.
Carpet 110 is loaded into a tenter frame 100 which will pull the carpet 110 through an oven while stretching it. The selvage 112 of the carpet 110 has been pierced by the pins of the pin chain 120 so that the carpet 110 may be stretched. If the carpet 110 is not pressed down, it may disengage from the pin chain 120.
The first brush 130a is in position to press the carpet 110 onto the pin chain 120 as it is drawn forward by the pin chain 120. The first brush 130a will rotate around the first post 134a in accordance with the forward movement of the carpet 110. While rotating, the bristles of the first brush 130a will press the selvage onto the pins.
All of the brushes 130a-d are rotatably secured to a base plate 140. That is to say that the first brush 130a rotates around a first post 134a to keep pressure on the carpet 110 so that the bristles are continually pressing down on the selvage 112.
As has been noted, the bristles of the brush 130a may become engorged with latex, which is still in an aqueous solution before it enters the oven. If the brush picks up too much of the latex, the brush may not be effective in pressing down on the selvage to keep it engaged with the pins. In some cases, it has been known to damage the pins.
In the illustrative embodiment of
In operations, the base plate 140 may be rotated as needed, either by an operator or through automation, as needed to keep a fresh brush in contact with the selvage 112 while the tenter line is continuing to draw the carpet 110.
The automated brush replacement device may be secured in place relative to the tenter line with a stationary bracket 142. This may be statically located where the positions of the brushes 130a-d are fixed relative to the hub 258, or the stationary bracket 142 may be adjustable so that the distance between the active brush, which is the first brush 130a in the illustrative embodiments of the figures, and the pin chain 120 may be adjusted. For the latter embodiment, the entirety of the automated brush replacement device may be raised or lowered to adjust the distance between the center of each brush 130a-d. This may be useful if brushes with different bristle heights are used or to make allowances for carpets with different tuft and/or selvage heights go through the tenter line.
Those of skill in the art will also understand that the brushes 130a-d need not be oriented in positions vertical to and horizontal to the center of the hub 258. The distance between the ends of the first brush 130a may be set by fixing the stationary bracket 142 to be a minimum distance from the pin chain 120. If a greater distance is needed, the base plate 140 may be rotated. This rotation of the base plate 140 will increase the vertical distance from the ends of the bristles to the pin chain 120. In this way, similar forces may be applied to the selvage 112 even if one carpet has a thin primary backing and a subsequent carpet has a thick primary backing.
In some embodiments, it may be preferable to have means of determining when a post is at a nadir position while an opposing post is at an apex relative to the selvage. In this, an operator need not visually inspect the alignment of the posts, but may rely upon the automated means to position the base plate so that the engaged brush is at a point nearest to the selvage.
While the illustrative embodiments of the figures show one automated brush replacement device on one side of the tenter line, those of skill in the art will understand that a corresponding automated brush replacement device may be located on the opposing side.
The illustrative embodiments of the figures are also not limited to a single automated brush replacement device on each side of the tenter line. In some embodiments, it may be preferred to have two or more automated brush replacement devices on each side of the tenter line. This is illustrated in the exemplary embodiment of
In many cases, access to a tenter line is restricted while it is in operation. That is to say that if there is a possibility that an operator may be hurt by any of the mechanisms within a safety zone, no people are allowed near the tenter line while it is running. As noted, this has then required that the tenter line to be stopped when a brush needed to be replaced in prior art systems. With the automated brush replacement device as disclosed and taught herein, an operator may rotate out an engorged brush and replace it with a fresh brush. This may be done remotely by an operator where the operator is safely distanced from the tenter line and outside of the safety zone. This may be done if the controls to activate the motor 150 are located remotely away from the automated brush replacement device and the tenter line. This may be done at an operator's station where an operator may be able to watch each automated brush replacement device through a video monitor and then activate any of them to replace an engorged brush with a fresh brush.
As noted, the exemplary automated brush replacement device has four brushes 130a-d. However, other embodiments need not be limited to four brushes. Applicant has found that embodiments of tenter lines where each automated brush replacement device has four brushes on each base plate allows for the brushes of each automated brush replacement device to run for an entire day. At the end of the final shift in a day, the tenter line may be stopped for other maintenance. During this stop time, all of the brushes 130a-d may be replaced with fresh brushes. This will allow the automated brush replacement device to be ready for another full day of continuous operations of the tenter line.
While the base plate 140 is illustrated as being circular, it need not be so. Any configuration will be consistent with the inventions disclosed herein as long as the posts to which the circular brushes are attached are spaced apart so that the base plate may be rotated so that a circular brush may be positioned where it will press the selvage onto the pin chain.
The posts need not be spaced equally distant from a rotational center of the base plate. In one envisioned embodiment, circular brushes having different characteristics may be used in the automated brush replacement device. Using the illustrative embodiment of
In another envisioned embodiment, the posts may be movable on the base plate. In one envisioned embodiment, one or more of the posts may be moved by an actuator along a path radiating from the rotational center of the base plate. In this, the operator may desire to have an active circular brush closer to or further away from the rotational center of the base plate. When the circular brush is further away from the rotational center of the base plate, its bristles will press with more force on the selvage and pin chain, and when the circular brush is closer to the rotational center, it will press with less force.
In prior art embodiments of brushes being held stationary above the pin chains, a quick release mechanism has been used to secure the brushes to their posts. Similar posts 134a-d may be secured to the base plate 140. The brushes 130a-d may then be the same type of brushes used in prior art implementations. This allows that any means that facilitates the rotation of the brushes 130a-d, such as bearing and lubricating assemblies, may still be usable in Applicant's automated brush replacement device.
In a preferred embodiment, each circular brush 130a-d may be made of bristles arranged around the outside of a cylindrical core. When the cylindrical core is affixed to a post on the base plate, the distance from the inside of the cylindrical core to a distal bristle will be long enough to push against the selvage on the pin chain with sufficient force to keep the selvage in place. To apply this force, the distance from the post to the nearest pin on the pin chain will be less than the distance from the inside of the cylindrical core to the ends of the bristles.
To facilitate the exchange of all brushes on an automated brush replacement device, the brushes may be secured to their posts 134a-d with removable pins 132a-d. The removable pins 132a-d may be cotter pins, threadable members, or any other type of mechanism that will quickly and easily allow for the release and reattachment of a brush.
Those of skill in the art will understand that the rotation of the base plate 140 by a shaft 256 is one embodiment of the inventions disclosed and taught herein. Other means for rotating a base plate having more than one circular brush may be envisioned by those of skill in the art without deviating from the inventions claimed herein.
| Number | Date | Country | |
|---|---|---|---|
| 63609421 | Dec 2023 | US |
