LARGE DIAMETER ROLLER CLASSIFICATION SYSTEM

LARGE DIAMETER ROLLER CLASSIFICATION SYSTEM

The Large Diameter Roller Classification System is intended to provide the manufacturer of high precision roller bearings an automatic method for separating production lots of rollers into precision classified groups, according to diameter. The part handling mechanism has been specifically designed to eliminate part handling damage, which can easily occur when handling large rollers. Most part transfer contact points are made from delrin, others are maybe from highly polished low-hardness steel.

The system is equipped with an inclined feed track which serves as the part input store as well. This track may be operator loaded or interfaced to the customer’s automatic parts feeding system. In general, the large parts will be operator loaded in order to prevent damage by an automatic feeding system. Parts are escaped one at a time at the end of the feed track onto the part transfer track.

The part transfer track serves to advance a part cycle by cycle from the infeed track escapement to the diameter measurement station, and to each of twelve possible classified output tracks. This mechanism allows for integrating other inspection requirements as additional stations. Additional inspections which can be performed as options are length measurements as well as surface inspection.

The measurement station is equipped with part clamp cylinders, which moves a part from the transfer track to a precision Vee locater. The Vee locater is configured to locate cylindrical as well as sphere rollers. A clamp positions and hold the part into the Vee for measurement. The measurement is performed by moving a differential set of gauge fingers through the maximum diameter of the part. The finger movement is provided by a precision x, z slide controlled by stepping motors. This provides the ability to take multiple diameter measurements axially along the part as well as through the maximum diameter radially. A large number of readings are taken about the maximum diameter and then fit to a parabolic function. The maximum for the function is calculated and set to the diameter after being scaled to engineering units. This method provides a high degree of repeatability and accuracy in the presence of part contamination and misposition. Other benefits are that part location tooling is not ultra-critical and the measurement is not static, therefore producing a faster rate and at the same time guaranteeing that the maximum diameter was encountered during the measurement. The processed part diameter is then assigned a classification group value and placed back onto the part transfer track.

Based on the classification, the part will be pushed onto the appropriate output track once it has been indexed to the required output track. Small parts can simply enter the track and then fall into the containers if part to part contact is not an issue. Larger parts are accumulated on the track until it becomes full, then the machine pauses and indicates to the operator that a track is full, and needs to be manually cleared.

The system electronics consists of a ruggedized IBM PC compatible processor. The processor is interfaced to the system motion control components via a standard OPTO-22 interface. The LVDT is signal conditioned by an IISD developed module which provides low noise, high response, and extremely stable signal conditioning for the LVDT probe. A supplied hard drive serves to store the application program as well as to store part parameter files and measurement results.

The applications software provides the user with a simple pull-down menu structure to access the various features of the system. In manual, the user is able to view the system inputs, control the system outputs, setup and calibrate the measurement station, and create and edit part parameter files. In automatic, the system will automatically cycle as parts are measured and classified. As the system cycles, the measurement files are saved to a data file, and a number of inputs are monitored to determine the existence of any system faults. The system will continue to cycle until the infeed becomes empty, an output track becomes full, or an error condition is encountered. All system stops are indicated by a stack light and with the offending condition posted on the CRT screen.

SIZE:………………………………..…….6’L X 4’ W X 5’H

ELECTRICAL REQ:………..115VAC, 60 Hz, 1 Phase @ 5A

AIR:…………..………….Shop Air @ 50PSI min. @ 4 SCFM

PART RANGE:………………….15-1.75”L X .15-1.75” Long

OUTPUT CLASS POSITIONS:………………….…….Twelve

CYCLE TIME:…………………………….2 seconds/part max

MEASUREMENT REPEATABILITY:…………+/-.000002”

MEASUREMENT ACCURACY:…………………+/-.00004”