Executive
branches are combination one either two of the same type working organs and combines with a screw executive branch, fig. 1.1 or two
working organs in combines with a drum with the vertical axis of rotation an executive branch,
fig. 1.2.
Fig. 1.1 is
Type of screw working organ
Fig. 1.2 is Type of drum working organ
The executive branch of modern cleansing combines simultaneously performs the two duties - destruction of layer and loading of the blasted coal on a face conveyor. Therefore the basic requirement to the executive branches of cleansing combines is exceeding of the productivity of organ on loading of coal above his productivity on destruction of layer.
Except for the basic requirement, to the executive branches of cleansing combines the row of other no less important requirements is produced: subzero specific expenses of energy of destruction of layer and loading of the blasted coal; minimum dynamic quality of working process and power spatial even temper; enhanceable wearproofness; simplicity and technologicalness of construction; high к.п. д.; simplicity of replacement of organ is in mine terms; reliable fastening of working instrument on an organ in combination with simplicity of his replacement and row of other of requirements.Destruction of layer the executive branch of combine is produced at in relation to not high-rate (cutting speed, as a rule, does not exceed a 3 m/of с) and considerable forces the average of which arrives at ten of thousands Newtonian. Therefore to the executive branch the requirement of durability is produced, in addition. The last stipulates the increase of his geometrical parameters and diminishing of free space of organ related to it, in which must take place and move the coal blasted by him.
It is special it is important for the combines of thin layers, as diminishing of free space of organ conduces to the considerable decline of his loading ability and productivity of combine, with one, and to the additional compression of coal, being and moving in an organ, and power character of process of loading of coal, on the other hand. The further increase of energyarmed of combines, being one of important possible ways of increase of their productivity, yet more aggravates this problem, especially for the cleansing combines of thin declivous layers.
Structurally worker of organ of combine, is two united inter se hollow cylinder. One of cylinders, called a pipe of worker of organ, a 325-360 mm and length 560 or 690 mm has an outward diameter depending on the nominal width of capture of organ (0,63 or 0,8 m) and which blades are set on. Second cylinder the outward diameter of which is stipulated by the diameter of worker of organ on chisels (560, 630, 710 or a 300 mm), in fist, radial, by structural flight of chisel, and in thick, as a rule, 70-75 mm. Drum with the vertical axis of rotation a working organ of cleansing combine is also two,
but mobile united inter se, special hollow cylinder, on the side of which fists is fastened. Mobile connection of cylinders of drum enables smooth
adjusting of working organ on a height (powers of layer). Except for it, in a
drum working organ step (by means of detachable disks) his adjusting is
foreseen on a height. The nominal width of capture of drum with a vertical axis
rotation of executive branch makes a 0,8 m. Therefore the diameter of organ on
chisels is made by a 1000 mm (a diameter of drum with the purpose of providing
of the proper loading of the blasted coal always must be more width of
capture). The diameter of outward surface of cylinders
makes 700 мм. Direct destruction of layer is produced by a
toolpiece which is definitely situated on the working (executive) organ of
combine. The location of toolpiece on
the working organ of combine of 1 is presented on a fig. 1.3.
Picture 1.3 Chart of set of chisels for cleansing combine
The chart
of set of toolpiece is characterized by the row of parameters :
- a cutting
(directly on a chart this parameter is not present) line is track, leave a
chisel on the surface of coalface
- number
chisels in the lines of cutting - amount of chisels, located in one line of
cutting
- thickness
cut (directly on the chart of set of this parameter it is not) is this
distance, passed by a combine (by a working organ) for one turn of organ and
being on one chisel in the line of cutting
- width cut
is distance between the nearby lines of cutting.
Forces (Н) and moments (Нм), operating on an executive branch :
|
Fo |
Fx |
Fy |
Fz |
Mx
|
My |
Mz |
Kнч |
1,25 |
1,2 |
3,55 |
1,13 |
1,15 |
1,25 |
1,3 |
Thus the values of efforts in chisels on the different lines of cutting are presented on a picture 1.3. Maximal effort is evened more than two kilonewton, Fz = 2,48Кн
The
improved chart over of set of chisels is brought on a picture 1.4.,
coefficients of unevenness on table :
|
Fo |
Fx |
Fy |
Fz |
Mx
|
My |
Mz |
Kнч |
1,02 |
1,15 |
1,2 |
1,07 |
1,18 |
1,02 |
1,24 |
Picture 1.4 New chart of set of chisels for cleansing combine
Thus maximal effort arrives at only Fz= 1,243Кn
At the new chart of set of chisels, coefficient of unevenness to diminish