Solid material comminution or disintegration – Apparatus – Comminuting elements
Reexamination Certificate
2001-02-06
2004-03-23
Rosenbaum, Mark (Department: 3725)
Solid material comminution or disintegration
Apparatus
Comminuting elements
C029S895200, C411S433000, C411S395000, C492S045000
Reexamination Certificate
active
06708912
ABSTRACT:
BACKGROUND
The present invention involves an improved chopper for chopping continuous or very long fiber, fiber strands, yarn, string, wire, ribbon, tape and the like comprising a backup roll and a blade roll. More specifically, the present invention involves a chopper having a novel quick release knock off-knock on roll retainer for the rolls that must be frequently changed, and means for tilting the chopper to change the angle of discharge of the chopped strand, etc.
It has long been known how to chop continuous fibers or fiber strands into short lengths of about 3 inches or shorter. More than a billion pounds of such products including chopped glass fibers and fiber strands are produced each year in processes and chopping apparatus like those disclosed in U.S. Pat. Nos. 5,970,837; 4,398,934; 3,508,461; and 3,869,268. The choppers disclosed in these patents comprise a blade roll containing a plurality of spaced-apart blades for separating the fibers into short lengths, a backup roll, frequently driven, which the blades work against to effect the separation and which pulls the fibers or fiber strands, often using an idler roll to hold the fibers or fiber strands down onto the surface of the backup roll. In the chopped fiber processes disclosed in these patents, the chopper is usually the most productivity limiting equipment in the processes that typically operate continuously every day of the year, 24 hours each day. Therefore, improvements in the chopper that allow the chopper to pull and chop faster, allow longer times between maintenance shutdowns, and/or to pull and chop more fibers or fiber strands at a time have an extremely positive impact on productivity and production costs.
Due to wear, the blade roll and backup roll on each chopper must be changed frequently with the actual life between changes depending upon the type of item being chopped. The life typically ranges between 4 and 24 hours or more, but a defect in a blade or the elastomer layer on the backup roll can cause even shorter life. Due to their tightness on their spindles and the tacky chemical sizing from the fiber that gets on all exposed parts, it has been necessary to strike the old blade rolls and old backup rolls with a hammer or a heavy bar to loosen them from their spindles before they could be removed for replacement with new rolls. This hammering damages the rolls and in time knocks them out of alignment causing vibration and premature replacement. These are expensive problems for the industry considering that there are hundreds of fiber choppers in operation.
Another problem with fiber choppers when chopping wet fiber having a tacky chemical sizing on the surface of the fibers is that the stream of fibers will, depending on factors such as moisture content and the degree of tackiness of the sizing, leave the chopper at different angles. This presents a problem in catching the fiber with a conveyor belt due to the limited space in the fiber forming rooms where the fiber is formed and chopped and results in some fiber being thrown off the conveyor and onto the floor causing scrap and a housekeeping problem. This problem is discussed in U.S. Pat. No. 4,161,897 and the problem is addressed in that patent by designing the chopper such that the position of the blade roll can be changed to contact the backup roll in different locations. While this may change the angle of discharge of the chopped fiber, it greatly complicates the design and is a costly solution. A simpler, less costly solution has been needed.
SUMMARY OF THE INVENTION
The present invention includes an improved chopper that comprises a backup roll and a blade roll, each roll being mounted on a spindle with a novel fast acting knock off/knock on roll retainer for holding the blade roll and/or the backup roll in place and for pulling the roll(s) loose from its spindle. This roll retainer assembly comprises a spinner attached to a stub shaft at or near one end, the stub shaft having engaging means that will engage with the spindle for the roll, a locking cup surrounding the stub shaft and free to rotate around the stub shaft, the locking cup having a depression therein with an opening facing away from the spinner, a lock-ring or collar surrounding the stub shaft and residing in the depression in the locking cup, the lock-ring being fixed to the stub shaft. The roll retainer also comprises a locking plate attached to the open end of the lock cup, the locking plate having two or more slots therein for allowing heads of shoulder bolts that are fastened to the blade roll and/or backup roll at locations spaced from the axis of the roll to pass into or through the slots in a wide portion of the slots. At least one end portion of each slot is narrower than the heads are wide such that the heads cannot pass through the narrower end portion(s) of the slots.
Preferably the assembly also includes a thrust washer or a lubricated washer around the stub shaft and between the spinner and the lock cup to enhance the tightening and loosening of the spinner. Preferably the roll retainer also comprises a lubricated thrust washer in the bottom of the depression in the lock cup to enhance relative movement under stress between the locking ring and the lock cup. Also, preferably the roll has two or more shoulder bolts circumferentially spaced around the opening, most preferably equidistant from each other and from the axis of the roll. This chopper can also comprise means on or attached to the chopper for lifting one side of the chopper to tilt the chopper to change an angle of discharge of an array of chopped product discharging from the chopper.
The present invention also includes a fast acting roll or wheel retainer comprising:
a) a cylindrical stub shaft having one end portion threaded,
b) a locking ring having a spaced apart parallel surface perpendicular to and surrounding the stub shaft and being either integral with the stub shaft or being rigidly attached to the stub shaft,
c) a spinner having one or more handles, the spinner being located at or near an end of the stub shaft opposite the end that is threaded, the spinner being either integral with the stub shaft or rigidly attached to the stub shaft,
d) a lock cup having a bottom and an open top, the bottom of the locking cup having a hole therein and surrounding the stub shaft in a ratable manner at a location between the two ends of the stub shaft, the open top of the locking cup being closest to the threaded end of the stub shaft, and
e) a locking plate attached to the open end of the lock cup, the locking plate having a hole therethrough for the stub shaft to reside in a rotatable manner, the locking plate having one or more slot openings at least partially therethrough and spaced from the hole for the stub shaft, each slot opening having a wide portion and a narrower portion, one face of the locking plate being compatible with an engaging face on the roll or wheel and the area on an opposite face around the narrower portion of each slot being compatible to engage a bottom surface of an enlarged head of one or more projections extending from an outboard surface of said roll.
The present invention also includes a method of removing a used roll and replacing it with a new or repaired roll, each roll having an opening around its axis and at least two shoulder bolts with enlarged heads spaced from its axis and protruding from a face of the roll, on a chopper, or other apparatus, having a spindle with threads on a working end using a novel knock on/knock off roll retainer assembly that comprises a spinner attached to a stub shaft at or near one end, the stub shaft having engaging means that will engage with the spindle, a lock cup surrounding the stub shaft and free to rotate around the stub shaft, the lock cup having a depression therein with an opening facing away from the spinner, a lock ring or collar surrounding the stub shaft and residing in the depression in the lock cup, the lock ring being fixed to the stub shaft and a locking plate attached to the open end of the lock cup, the locking plate ha
Bascom Randall C.
Bryant Jeffrey James
Dachenhaus Gary Lee
Hyter Randy C.
Mead Archie
Johns Manville International Inc.
Rosenbaum Mark
Touslee Robert D.
LandOfFree
Roll retainer and fiber chopper does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Roll retainer and fiber chopper, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Roll retainer and fiber chopper will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3188806