Assembly Drawings 279
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d:\N-Design\Des18-1.pm5
Friction clutches which are in common use are of two categories—single plate/disc and
multiplate/disc clutches. In a single plate clutch, only one plate with one or two friction surfaces
is used. Figure 18.12a illustrates various parts of a single plate clutch. It consists of a flywheel 1
which provides one friction face. The flywheel is mounted on the driving shaft. The spring loaded
friction plate 2 is mounted on the driven splined shaft 11. The clutch pressure plate 3 is connected
to the cover 13 through clutch release levers 4, lever plate 5, lever fulcrum pin 6, by lever screw
7 and nut 8.
The driving flange 10 houses lever spring 9 along with the clutch pressure plate. The cover
is bolted to the flywheel by means of screws 14. The friction facings are riveted to the segments of
the spring loaded friction plate to give smooth engagement and prevent sticking.
When the clutch is engaged, the friction plate is sandwitched between the faces of the
flywheel and the pressure plate, thus transmitting power to the driven shaft through the friction
plate.
When disengaging, the clutch springs 12 act through the release levers and force the
pressure plate away from the friction plate, thus disengaging the driven shaft. Figure 18.12b
shows an isometric view of the assembly drawing of the single plate clutch.
Exercise
Figure 18.12 a illustrates the details of a single plate clutch. Assemble the parts and draw, (i) the
view from the front and (ii) sectional view from the right.
18.2.13 Multiplate Friction Clutch
In a multiplate friction clutch, a number of discs or plates with frictional surfaces on either side
are located alternately on the driving and driven shafts. By bringing these, close together by
external pressure, power can be transmitted from the driving to the driven shaft. Multiplate
clutches are normally wet type, whereas, single plate clutches are dry. The multiplate clutch is
located on the driving shaft. The pulley/wheel mounted on the shell serves as a driven member.
There is no driven shaft.
Figure 18.13a illustrates various parts of a multiplate clutch. The serrations on the internal
diameter of the shell 1, receive the alternate friction discs called the outside plates 3. The shell
along with a bush is mounted freely on the driving shaft, has provision to receive the driven
pulley or wheel. A centre boss 5 is keyed onto the driving shaft. The serrations on the centre boss
receive the alternate friction discs called the inside plates 4.
The front cover 2, is fixed to the shell by means of six small set screws 12. The front cover
is able to either slide or rotate freely on the driving shaft with the bush provided. The sliding
sleeve 9, rotates freely on the driving shaft and is connected to the front cover through three jaw
levers 7, and three L-levers 8. The last outside plate called a stud carrier 6, is provided with the
arrangement to carry three studs 10, which are operated by the sliding sleeve through the
L-lever.
The sliding sleeve rotates with the clutch body, i.e., the shell. The sleeve can be moved
forward by an operating lever (not shown) in order to exert pressure on the studs. The plates will
then get pressed together and the drive is completed. Figure 18.13b shows the assembly drawing
of the multiplate clutch.
Exercise
Assemble all parts of the multiplate friction clutch shown in Fig. 18.13 (a) and draw, (i) the half
sectional view from the front, with top half in section and (ii) the view from the right.
