Trailing arm secondary belt cleaner

A conveyor belt cleaning arrangement is provided in which belt cleaner blade(s) are positioned relative to a conveyor belt, which arrangement includes a mounting bracket, a transverse pivot support tube, a blade mounting tube with a rising male projection to engage a complementary female slot in the bottom of the blade, a blade with a female slot in the bottom to receive the male projection on the blade support tube, connecting arms and a pressure roller mounted on the opposite side of the belt to flatten and hold the belt in position, all of which act to clean material adhering to a moving conveyor belt when the cleaner blade is forced into transverse engagement with the belt.

This application claims benefit of provisional application Ser. No. 
60/005,950 filed Oct. 27, 1995. 
BACKGROUND OF THE INVENTION 
It has been shown in prior art to provide pivotally actuated mounting 
arrangements to force various types of belt cleaner blades into engagement 
with a moving conveyor belt. All of the conveyor belt cleaning blades of 
the prior art teach a flat blade being rotated from a pivot point into 
engagement with the belt, as the blade wears the angle that the blade(s) 
contacts the conveyor belt will change and therefore, the performance of 
the cleaning action will change. Additionally, the belt cleaner blade(s) 
tend to have erratic cleaning effect due to belt cupping (The tendency of 
the edges of the conveyor belt to turn downward along the longitudinal 
axis of the conveyor). On cleaning units with multiple blades having 
multiple support arms there is a tendency for material to build-up on the 
arms causing decreasing effectiveness of the belt cleaner. 
In the present invention an arc is provided in the blade and the pivotal 
mounting arrangement is positioned at the center of the blade arc, as the 
blade is rotated into engagement with the conveyor belt the angle between 
the tangent to the blade arc and the conveyor belt will remain constant as 
the cleaner blade wears. 
By providing a second arc with the same center point to form the back side 
of the blade the area of the blade in contact with the belt will be the 
same throughout the life of the belt cleaner blade. 
The constant angle of attack and the constant cross-sectional area are 
important in maintaining consistency in cleaning. 
A pressure roller is provided to flatten the belt in the area where the 
belt cleaner blade is located. 
SUMMARY OF THE INVENTION 
One object of the present invention is to provide a conveyor belt cleaning 
arrangement which is mounted on the return side of a conveyor belt and 
will maintain a constant angle of attack and a constant cross-sectional 
area of contact with the moving conveyor belt throughout the useful life 
of the belt cleaning blade. A rigidly supported roller mounted transverse 
to the direction of the conveyor system and on the opposite side of the 
belt holds the belt in proper position for the belt cleaner blade to 
contact the belt surface. Two connecting arms one on each end of the blade 
mounting tube support the belt cleaner blade while remaining clear of the 
area below the belt where build-up from the belt would occur.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 illustrates a simplified perspective of a mechanical conveyor belt 
cleaner designated by the numeral 13 and includes a pivot cross-shaft 9 
with a telescoping extension 7 on each end of the cross-shaft. The 
telescoping ends 7 extend into the square cross-shaft 9 and through a 
round hole in mounting bracket 8 which would normally be mounted to some 
portion of the conveyor structure. Two blade pivot arms 5 are slidably 
attached to the pivot cross-shaft and lockably secured with pivot arm 
pivot shaft collar set screw 12. The other end of the two blade pivot arms 
5 are attached to the conveyor cleaner blade cross shaft 4 through pivot 
arm collar 3 and secured with pivot arm collar set screw lock 11. Attached 
to the top of the conveyor cleaner blade cross shaft 4 is a rigid guide 2 
which engages a mating slot in belt cleaner blade 1. Two pins 10 lock the 
belt cleaner blade 1 to the rigid guide 2. Pressure roller bracket 14 is 
rigidly attached to conveyor frame at mounting bracket 8. Mounted to the 
roller bracket is a bearing 15 which carries the pressure roller 16. 
FIGS. 2 and 4 illustrate the uniqueness of the present invention. FIG. 2 
shows that the pivot point for the belt cleaner blade 1 is at the center C 
of the blade face 18 curvature arc back side 19 of the blade is formed 
from a second concentric arc using the same center point. FIG. 4 shows 
that the angle of attack A (shown as 77.2 degrees) between the belt 17 and 
the leading blade face 18 remains constant throughout the life of the 
cleaner which is important to consistent cleaning action, additionally the 
geometry of the blade and the mounting of the pivot point at the center of 
the blade arc provide for a constant blade contact area after the initial 
wear-in of the blade. 
By changing distance "D" shown in FIG. 2 the angle of attack will change 
and the cross-sectional area will change, this feature is desirable to 
optimize the cleaning action of the cleaner to various materials with 
various properties of adherence to the conveyor belt. 
FIG. 3 illustrates the location at B where build-up normally occurs when 
using belt cleaners that incorporate multiple blades and support elements.