Front punched brushes
They are brushes with the working surface perpendicular to their axis of rotation, and are therefore suitable for processing flat surfaces, and are motorised The working surface can be continuous or segmented.
Front brushes are used for :
- Mechanical cleaning of flat surfaces
- Mechanical sanding of flat surfaces
- Deburring of mechanical parts, such as gear wheels, etc…
The tufts are generally straight, but it is possible to give them an angle as in the picture.
This can be useful to increase the working surface with the same brush body size. The angle α cannot generally exceed 15°.
As far as the power drive is concerned, the case of the front brush is the most onerous.
In fact, compared to a roller of the same length, for example, all the tufts are simultaneously gripped here. You can size the engine using the following formula: P = (n x N x F1 x R) / 1000 where: P is the required engine power [KW] N is the number of tufts R is the brush radius [m] n is the brush speed [rpm] F1 is the maximum tangential force applicable to the individual tuft [Kg] and it is experimental. The power varies from 0 to P depending on the pressure applied to the brush.
The brush body is generally synthetic, but also in aluminum in case of flatness tolerances.
Normally these brushes are mounted on a motorised shaft. For this purpose, a recess can be made to hold the clamping nut, and a keyway can be made to hold the drive. The brush body can also have special shapes for assembly and handling on automatic machines. It is generally obtained by machining, but when it has complex shapes it can be produced by low-pressure moulding or, with large quantities, by injection moulding.
The special feature of the brush is that the work surface is made up of millions of individual elements, which are the ends of the individual filaments.
This gives the brush an adaptability that no other element, however deformable, can have.
It depends on various factors. In a nutshell, it can be said that 2 mm is a good compromise. The important thing is that the filaments of the brush work “at the tip” and not on the side.
Depending on the materials used and the dimensions, there is a tensile limit load that a single bunch can withstand.
Beyond this limit the bunch comes off, therefore the brush must be calculated according to the use. This limit can be greatly increased by building “sewn” or “tied” brushes by hand, where a continuous steel wire is placed instead of a single anchor element.
There is no single answer. Speaking for example of cylindrical brushes, the strip brush is generally cheaper when dimensions are important (e.g. over one meter in length). For small dimensions, punched brushes are certainly more suitable and convenient.
It can only happen if the brush has a manufacturing defect, like any other type of object (e.g. a roller made with silicone flakes, one of which is defective and breaks).
When it is important that no contamination occurs, it is advisable to use synthetic (non-natural) fibers with a diameter greater than or equal to 0.15 mm.
Virtually all degrees of hardness can be had, from very soft to very hard. In fact, the hardness is given by the combination between the diameter of the filament, its free length and the density of the bunches.
Of course, we can provide FDA or FOOD GRADE certifications and filament traceability.
Unfortunately not, as it is the machine + brush assembly that must be ATEX certified, not just the brush.
It is however possible to provide the materials that the certifier requires, eg. conductive bases, conductive filaments etc …
Generally speaking it is possible, but it is necessary to evaluate if it is economically convenient, and it is not always. Furthermore, in the case of a punched brush, it is not advisable to regenerate the brush more than twice in order not to reduce the holding of the bunches.