This invention relates generally to material handling and feeding equipment and, in particular, to improvements and modifications associated with coil steel straighteners.
The metal forming and stamping industries commonly use material handling and feeding equipment to process coil steel into stamping presses and other metal forming machinery. This equipment includes coil unwinders, straighteners, threading equipment and feeders to handle, unwind, straighten and feed unprocessed coil metals, and to flatten the material adequately so that it can be presented to presses for forming or stamping processes.
Conventional straighteners utilize a series of rollers of various diameters, spacing, and width that are sized to match press capacities and metal properties. The aligned rollers, configured in upper and lower banks, are located on both sides of the presented material to apply adequate bending to stress the material beyond its yield strength. The rollers (banks) must be precisely positioned during equipment build and properly supported or “backed up” to counter the internal loads and stresses experienced during processing.
It is common that the upper and lower roller banks are supported with backup rollers to provide the necessary support and rigidity to prevent the work rollers from deflecting. However, the technique and features to allow precise and controlled positioning, timing, and alignment of the backup rollers are complicated to implement and maintain on given pieces of straightener equipment.
This invention resides in various improvements and modifications applicable to coil steel straighteners. These improvements and modifications provide an integrated structural head that allows for quicker setup of the equipment, integrated lower backup rolls to the structural head, self-aligning rollers, setup timing blocks for equipment calibration, and adjustment screw jacks that allow for narrower center distances and include pointers and scales internally. The improvements and modifications are patentably distinct, such that they may be implemented separately or, more preferably, in combination.
Applicable straighteners include upper and lower banks of work rollers for receiving material to be straightened, each work roller being rotatable about a respective axis of rotation. A plurality of backup rollers associated with each work roller reduce deformation of the work roller during the straightening operation.
In accordance with one embodiment of the invention, the backup rollers for each work roller are supported on separate backup roller plates that are longitudinally aligned with the work rollers, enabling the backup rollers for each work roller to removably installed and independently adjusted. The backup rollers may be supported between opposing blocks and adjusted by moving the blocks toward and away from the backup roller plate using leveling jacks that are fixed in position with jam nuts once the desired degree of contact is achieved. Longitudinal support plates may be affixed to the back surface of each backup roller plate to reduce deformation of the backup roller plates.
The work rollers associated with the upper bank may be supported between opposing slide blocks that move up and down in slots formed in opposing side plates, and the slide plates and slots may include visual indicators to establish a zero position associated with each work roller in the upper bank. In the preferred embodiment, the visual indicators are notches or cutouts in the slide blocks and the slots. The notches or cut-outs in the slide blocks may be precisely located based upon the distance to the center of the work roll in that slide block, or the notches or cut-outs in the side plates are precisely located based upon the distance to the plane of the lower work rolls. In any case, the zero position may be used to calibrate encoders, digital readouts or mechanical scale markers.
As mentioned in the Background of the Invention, straighteners include upper and lower banks of straightening rollers or “work rolls” that are supported or “backed up” with upper and lower backup rollers to keep the work rolls properly aligned and free from deformation. As such, the backup rollers need to be positioned accurately against the work rolls to provide uniform contact and without applying too much pressure. Traditionally, however, the lower backup rollers were coupled to structures associated with the cabinet or support base. However, this configuration results in an arrangement that is difficult to assemble and difficult to maintain.
One aspect of this invention provides a separate backup roller assembly enabling the rollers to be assembled and aligned independently of the equipment, facilitating easier installation and maintenance.
The invention allows the components of
Once the backup roll assemblies are mounted in position, another aspect of the invention makes movement of the backup rollers against the work rolls much easier. As shown in
At this point, the leveling jacks are adjusted until they come in contact with blocks 202 and 302. Once the leveling jacks are in position, the jam-nuts 212 and 312 are used to lock the leveling jacks 210 and 310 to the support frame 204 and 304. Then the locking bolts 213 are tightened to secure the end blocks 202 and 302 to the leveling jacks.
In most instances the leveling jacks may be hand tightened since the idea is to make contact to the work roll without applying too much pressure. The use of leveling jacks and tension springs enables the rollers to automatically adjust and compensate for equipment and material variations so as to maintain a consistent and even straightening process. This decreases the required setup time and field preventative maintenance required to maintain parallel rollers relative to each other and the head.
While the lower work rolls are fixed in position, alignment may be established through precise machining. However, since the upper work rolls are adjustable using screw jacks and slide blocks, located at opposite ends of each upper work roll, alignment accuracy, relative to the fixed lower work rolls is particularly challenging. The upper work rolls must be made perfectly parallel to the lower work rolls by adjusting each end, individually, and then locked together, using cross shafts on the screw jacks, to ensure correct straightening operation without damage to the material.
In straightening equipment, calibration of upper work roll position relative to a “known zero” position is critical to allow the end user the ability to precisely adjust the work roll engagement for their specific material properties while straightening. It is also crucial to allow the software controls to maintain a precise reference position to calibrate the encoders, digital readouts, and/or mechanical scale markers.
Any time service or repair requires removal of the rollers, the technician or customer is required to calibrate the upper work rollers to the known “zero” position. In the past, long relatively heavy “timing bars” were placed between the upper and lower work roll banks to establish a “zero” position. It is standard industry practice to then use “off the shelf” screw jacks to provide the forces required to position and hold the rollers in the correct position for the material being processed. This calibration process is tedious and tends to be underperformed, reducing the quality of the material being processed.
A different aspect of the invention allows for quick and precise alignment and calibration of the straightener roller banks and can also be used for the material edge guides on the straightener. As shown in
The center slide block in
The cut-outs in the slide block may be precisely located based upon the distance to the center of the work roll in that slide block. The cut-out in the side plate may likewise be precisely located based upon the distance to the plane of the lower work rolls. Once a zero location is established, this position may be used to calibrate encoders, digital readouts, and/or mechanical scale markers. In the preferred embodiment, custom screw jacks are then used to allow for tighter center distances of the rollers while producing the required forces to hold the roller in position. By decreasing the roller center distances the straightener can affect the material more precisely.
This application claims priority to U.S. Provisional Patent Application Ser. No. 62/441,616, filed Jan. 3, 2017, the entire content of which is incorporated herein by reference.
Number | Date | Country | |
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62441616 | Jan 2017 | US |