United States Patent 3916045
Abstract:
Card Clothing wire is coated in strand form with a permanent baked on layer of polytetrafluoroethylene.
Inventors:
Ibbotson, Peter (Liversedge, EN)
Grimshaw, Keith (Todmorden, EN)
Application Number:
05/323651
Publication Date:
10/28/1975
Assignee:
The English Card Clothing Company Limited
Other Classes:
19/114, 140/97, 427/424
International Classes:
D01H4/32; D06M11/83; D06M15/256; D01H4/00; D06M11/00; D06M15/21; (IPC1-7): B05D7/20
Field of Search:
117/37R,128,128
Other References:
Ashworth Bros., Inc., Fall River, Mass., Oct. 21, 1970, p. 7..
Primary Examiner:
Herbert Jr., Thomas J.
Assistant Examiner:
Hess, Bruce H.
Attorney, Agent or Firm:
Norris & Bateman
Claims:
We claim
1. A method of treating a strand of card clothing wire, in which the wire is coated with polythetrafluoroethylene and the coating is baked by heat treatment so that it becomes secured in a permanent manner on said wire.
2. A method of treating card clothing wire, in which a coating of polytetrafluoroethylene is applied to the wire in strand form after the formation of teeth on the wire, and said coating is secured to said wire by baking so that it becomes secured in a permanent manner on said wire.
3. Card clothing which includes carding wire coated in strand form with a permanently applied baked-on layer of polytetrafluoroethylene.
Description:
One of the most important drawbacks to the use of card clothing in the textile industry, is the tendency of materials encountered in carding to adhere to the card clothing on the rollers or flats of the carding machine. For many years, it has been the accepted procedure to fettle or clean the card clothing on the machine periodically, but this of course necessitates an interruption in the productive capacity of the machine. With the advent of high production carding machines, any such interruption can be expensive.
It is the object of the present invention to provide card clothing which at least minimises the disadvantage referred to above, and it should be mentioned that the invention is of particular advantage with metallic wire card clothing, although it could also be used on foundation type card clothing.
According to this invention metallic wire for card clothing teeth while in strand form is coated with a permanently applied coating of polytetrafluorethylene release agent.
The coating is of a permanent nature, that is to say it is bonded to the teeth in such a manner that it will not easily wear off, and in this sense, the invention is distinguished from the mere treatment of card clothing by the spraying of such release agents as silicone oils.
A suitable material for coating the teeth is that sold under the registered trade mark `Teflon` or Fluon`.
Three ways of carrying out the invention will now be described, by way of example only, with reference to the accompanying drawing which shows schematically a continuous process of treating card clothing wire with P.T.F.E.
As shown in the drawing a strand of metallic wire card clothing 10 is traversed continuously under a spray 12 of pure polytetrafluoroethylene resin, so that it is coated all over with a film of the P.T.F.E. Beyond the spray 12, the wire 10 passes under heaters 14 which bake the P.T.F.E. on to the steel wire which is toothed as shown. The wire can then be wound on to a drum or roller of a carding machine and will function in the conventional manner.
When the carding machine is in operation, the P.T.F.E. coating acts as an anti-friction material relatively to grease, added oil, and like foreign matter, particularly in the grooves between adjacent convolutions of the card clothing wire. It will be appreciated therefore that the invention is of particular significance, in woollen carding, although it is by no means limited in its application to woollen carding machines.
The `non-stick` properties of the P.T.F.E. coating are primarily intended to prevent the accumulation of foreign matter in the card clothing when it is applied to the roller or flats of the carding machine, but it will be appreciated that it might also have some advantageous effect on the carding section of the teeth relatively to the fibres themselves. Therefore, in practice, it might be found necessary to vary the construction of the teeth (in respect of such characteristics as angle of slope of the fronts and backs of the teeth or the pitch of the teeth) in order to obtain a specific carding effect.
In an alternative method, the strand of metallic wire card clothing is first immersed in a bath of water-based P.T.F.E. resin, so that when the wire is removed from the bath it is covered with a film of the resin before the treatment. The P.T.F.E. coating, by preventing contact between the steel wire and the atmosphere, reduces the danger of deleterious corrosion of the wire.
Although, in the above specific example, the coating of metallic wire card clothing has been described, it will be appreciated that flexible wire for use in foundation type card clothing could be similarly treated.