Conveyors: power-driven – Conveyor section – Reciprocating conveying surface
Reexamination Certificate
2002-04-11
2004-06-08
Ridley, Richard (Department: 3651)
Conveyors: power-driven
Conveyor section
Reciprocating conveying surface
C198S758000, C198S759000, C198S771000, C198S752100
Reexamination Certificate
active
06745893
ABSTRACT:
BACKGROUND
The present invention relates to a bearing system for suspending the swing frame of a conveyor grate in a swinging manner on a support structure. The bearing system comprises two elastic spring rods arranged next to each other in a common swinging plane. The first ends of the spring rods are clamped in a fixed manner in clamping points on a first structural component, such as the support structure. Their second ends are clamped in a fixed manner at connection points of a rigid coupling system. The coupling system is connected to the second structural component, the swing frame.
Conveyor grates generally have a multitude of grate rows, which are successively arranged one after the other and overlap one another in a step-like manner. Each second or third row can be moved back and forth, which periodically moves the material transported on the grates (i.e. cement clinker). The movable grate rows of a conveyor grate system are generally arranged on a common swing frame. The swing frame is moved back and forth by a swing drive. The grate rows have grate elements that are secured on grate supports. Thrust gaps exist between the moving and the fixed rows of grates. These gaps are the cause of grate wear and should be as narrow as possible. The size of the gap is a measure of the quality of the thrust grates. Narrow gaps can be kept clear of the material to be cooled by a high velocity cooling air. With large gaps and accordingly coarser material, the amount of cooling air required would be unjustifiably high. Material penetrating the thrust gaps causes wear in the area of the thrust gap, leading to an increase of grate loss, or material dropping through the gaps.
In the ideal case, the swing frame is moving in a linear way, so that the thrust gaps maintain their width as the swing frame is swinging. Gap width is predetermined in constructing the system. Support swing frames with linear mobility on rollers are known in the art. However, the wear of roller bearings leads to an undesired change of the width of the thrust gap.
In order to avoid linear bearings, DE 38 44 493 (von Wedel) proposes to suspend the one or more swing frames in a swinging manner on long leaf springs or spring rods. A basic drawback of swinging suspension is that the swinging movement causes a circular arc, wherein the swing frame and the rows of grates connected with the frame move along a circular arc as well. This makes it necessary to dimension the width of the thrust gap so that the vertical component of the circular arc movement is possible without causing the movable rows of grates to come into contact with the fixed rows of grates. On the average, this results in a relatively large thrust gap width and the undesirable consequences described above. The vertical component of the circular arc movement becomes smaller as the pendulums become longer. Long pendulums, however, lead to an increased structural height and increased space requirements for the entire conveyor grate system.
A bearing device of the type described above has been described in WO 98/40683, in particular
FIG. 3
of the patent. The bearing system has two elastic spring rods
7
b
, which are clamped in a fixed manner to the support structure and arranged next to each other in a common swing plane. The lower ends of the spring rods are connected with a rigid coupling system
13
via a fixed clamping system. The coupling arrangement is connected with the swing frame. The two spring rods
7
b
are arranged parallel with each other. The fixed coupling system
13
is connected with the swing frame at point
9
via another spring rod
7
a
. The structural length of the pendulums is halved by dividing the spring rods into two spring rod segments.
Forces are transmitted via the coupling arrangement from the lower end of the two first spring rod segments to the upper suspension point of the other spring rod segment. The lower end of the other segment is secured on the swing frame. The spring rod segments are inserted into one another in this manner and the structural height is substantially reduced to the length of the spring rod segments. Since the first spring rods are aligned parallel with each other, their movement results in a parallelogram displacement. The coupling system is moving along a circular arc corresponding with the circular arc described by the lower ends of the first spring rods. The spring rod secured on the coupling arrangement participates in the circular arc movement of the coupling system and additionally performs its own swinging movement that leads to a correspondingly superimposed movement of the swing frame.
A drawback of the known arrangement is that the vertical movement of the swing frame is similar to the movement of the spring frame with an undivided, long pendulum. In practical applications, the spring rod segments are, additionally coupled by coil springs, arranged between the spring rod segments. They transmit the full pendulum deflection introduced into the other spring rod segment to the first spring rod segments, to an extent amounting to half of the deflection. This adjustment is found to be difficult under the varying load conditions because a defined adjustment is always only optimized for one load case.
Another drawback is that the upper suspension point of the additional spring rod segment is located at a high level on the coupling system, and in an unstable manner. This makes it impossible to set an inclined plane of swinging in relation to the center of the conveyor grate, for the purpose of lateral centering in connection with the use of long pendulums.
SUMMARY OF THE INVENTION
The present invention provides a bearing system with the use of spring rods clamped in a fixed manner to a first structural component, where it is possible to achieve a linear or quasi-linear movement of the swing frame suspended in a swinging manner on the supporting structure. The deviation from the linearity must be smaller than the vertical component of the circular arcs of long pendulum systems, and pendulum systems where pendulums are inserted one into another.
According to the invention, spring rods are inclined in the plane of swinging toward one another. Further, the coupling system is connected to the second structural component via a connection (flexible joint) permitting tilting in the plane of swinging.
The consequence of the inclined spring rods is that with each joint deflection of the rods, the end of one spring rod always moves along a downward arc, whereas the end of the other spring rod moves along an upward arc. In this way, a coupling system connected with the spring rods is simultaneously displaced and tilted in the plane of swinging. The downward movement of one end of the coupling system is opposed by an upward movement of the other end of the structural element. An area then exists between the connection points of the spring rods that is moving in a linear or quasi-linear manner with a thrust movement that is adequately long for the application. In this area it is possible to tap the thrust movement of the wing frame.
Since the coupling system is tilted when the two spring rods are deflected, the connection of the coupling system with the second structural component must permit a tilting movement.
In a preferred embodiment of the invention, the spring rods each form the side legs of a trapeze, preferably of a trapeze having equally sized legs. This results in an arrangement that is simple in terms of construction and acts equally in both directions of deflection.
In further developing the invention, the spring rods each extend in a converging manner from their clamping points on the first structural component to the connection points connecting them with the coupling arrangement.
The flexible connection of the coupling system with the second structural component may be arranged in the coupling axis, preferably the center area of the axis. The coupling axis extends through the connection points of the spring rods with the coupling arrangement. However, it may be more favorable for system enginee
LandOfFree
Bearing system for the swinging suspension of the swing... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Bearing system for the swinging suspension of the swing..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bearing system for the swinging suspension of the swing... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3365267