Fitting doctor blades

Metal working – Method of mechanical manufacture – Assembling or joining

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

2483164, 269160, 269243, 269246, B23Q 300

Patent

active

045611637

DESCRIPTION:

BRIEF SUMMARY
This invention relates to the fitting of doctor blades in rotary printing machines. Such blades are commonly formed of relatively thin and flexible strip steel which is inserted into a blade holder in the machine.
A problem in the fitting of a new doctor blade to the blade holder of the machine is that of ensuring that the edge of the blade presented towards the circumference of the printing cylinder is precisely linear both axially and radially with respect to the cylinder, and that the extent of projection of the blade from the blade holder is constant along all of the length of the blade.
It is relatively easy to cause misalignment and even buckling of the relatively flimsy blade, in its own plane and/or normal to its own plane, and much skilled labour and time is currently occupied in ensuring that the blade, once fitted, has its scraping edge perfectly true.
It is accordingly the object of the present invention to provide a method, and a guide means for use in carrying out the method, which permit the fitting of a doctor blade strip into the usual holder in a simple manner with complete accuracy, and without requiring subsequent grinding or other trueing operating on the blade.
According to the present invention a method of fitting a strip-like doctor blade into a clamp means of a printing machine comprises the steps of: blade, which will eventually be exposed towards the cylinder, against a first linear stop surface of the guide means. condition, the first stop surface and spaced from the first stop surface in the direction towards the second edge of the blade, against the clamp means with a portion of the blade being inserted into the clamp means,
As the first and second stop surfaces of the guide are parallel, and the eventual scraping surface of the blade abuts one of them, and the other of them abuts the clamp means, the above series of steps ensures that the portion of blade which is eventually exposed from the clamp means is both linear and of the same extent of protrusion along the entire length. The distance of which the first and second stop surfaces are spaced is preferably made the same as the extent to which the blade is desired to protrude from the clamp means.
The application of force to the blade is preferably by use of tightening means of the guide. e.g. tightening of releasable holder means of the guide.
A guide for use in carrying out the method set forth above comprises an elongated body having along its length a first linear stop surface, to be abutted by a first edge of the blade, a second linear stop surface parallel to said first stop surface and spaced therefrom in the direction towards the second edge of the blade when so abutted, and means for applying force to the blade to hold it in abutted condition.
The means for applying force may be a plurality of holders positioned at intervals along the elongated body and capable of being released and tightened onto the blade.
In a preferred embodiment, the elongated body is a bar having a recess bounded by two surfaces forming an "L" shape, one surface forming the first stop surface, and the other such surface receiving the blade against it and serving in the application of force to the blade. By way of example the holders may be substantially L-shaped elements having one leg extending into said recess to hold the blade against said other surface, and the other leg provided with means for tightening onto the elongated body.
In a preferred modification, said other surface is stepped, thereby to permit one strip of a two-part blade to abut against the first stop surface, and other strip of the two-part blade to abut against the step.
In order that the nature of the invention may be readily ascertained, an example of the method of fitting a doctor blade into the usual clamp means of a printing machine, and a guide for use in carrying out that method, are hereinafter particularly described with reference to the figures of the accompanying drawings, wherein:
FIG. 1 is a partial front elevation of the guide;
FIG. 2 is a section taken on t

REFERENCES:
patent: 4323262 (1982-04-01), Arenhold

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Fitting doctor blades does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Fitting doctor blades, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fitting doctor blades will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1017143

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.