This invention relates to a device for measuring and calibrating the load of top arms of spinning machines.
The drafting zone of ring spinning or roving frame has a plurality of top arms and bottom rollers. Top arms are provided with a set of top rollers. The load exerted by the top arm through the top roller is uniformly distributed to the bottom rollers. The load of these rollers on the roving or sliver during the drafting stage determines the quality of the yam or roving produced. It is, therefore essential to measure and calibrate the load to be exerted by top arms for obtaining the desired quality of yam or roving.
Load is exerted by the top arm through a pressure hose connected to the top arm. This pressure hose is subjected to air pressure and (he air is received from an air compressor. Pressure built is transferred through the top arm to the rollers. One of the main factors that influence the quality of the yam or roving produced in the drafting zone is the pressure or load exerted by the top arm. It is therefore necessary to determine the amount of loadto be applied for the required quality levels.
The existing mechanical gauges in measuring top arm load are found to be inaccurate, time consuming and user unfriendly. The device developed by us overcomes these drawbacks. Accurate load testing, calibrating and digital display of the load are made possible by this device.

The device consists of a base frame member provided with a plurality of support members. These support members support the roller stands of the top arm when mounted. Mounting means having a configuration and profile for aligning the top arm therewith are also provided on the base frame member. The base frame member also accommodates a load cell which is preferably a piezo electric load cell. The load cell is connected to a digital display unit tor digital indication and display of the load of the top arm. This digital display unit consists of conventional amplifiers and convenors for converting the load pressure signals from the load cell to digital display.
Accordingly this invention provides a device for measuring and calibrating the load of top arms of spinning machines which comprises a base frame member provided with a plurality of support members, at least one mounting means having a configuration and profile for aligning said top arm therewith, and a load cell connected to a known digital display unit.
This invention and the method of its operation will now be described with reterence to figure I in the accompanying drawings.
Figure I is a sectional view of the device with the top arm mounted thereon for calibration and testing the load. B represents the base frame member while S and S1 are the support members. The top arm is

represented by reference numeral (1). The roller stand (2) rests on these support members. Reference letter M shows the mounting means which may be provided with taper bracket (8) for housing the load cell indicated by numeral (7). The top arm which indirectly rests on the load cell is represented by numeral (1) while numerals (3), (4), (5) and (6) show the three bottom rollers and the top roller. It is clear from this figure that the bottom roller rests directly on the load cell. The load cell may be any known load measuring cell such as a piezo electric cell. The display unit is connected to the load cell and is not shown in the drawings.
The load exerted by the top arm is measured and calibrated by placing the top arm of the spinning machine on the mounting means, such that the support members support the roller stands and the last of the bottom rollers rests on the load ceil. The pressure hose of the top arm is then connected to a compressor to exert pressure on the rollers. The load is detected by the load cell and signals are transferred to the display unit. These load signals are converted by the amplifiers and converters provided in this conventional display units which is then displayed on the screen. By this method, the pressure and the load derived therefrom can be co-related and calibrated to know the required amount of pressure to get the desired load from the top arm.

The device is capable of measuring a load within 0.1 kg accuracy. It is easy to operate and takes considerably less time than the conventional mechanical gauges available till now.
The device may also be used to calibrate other load imparting systems and is not exclusive to top arm load measurements.

WE CLAIM:
1. A device for measuring and calibrating the load of top arms of spinning machines comprising a base frame member (B) provided with a plurality of support members (S, S1) at least one mounting means (M) having a configuration and profile for aligning said top arm (1) therewith, and a load cell (7) conected to a known digital display.
2. The device as claimed in claim 1, wherein said load cell is a piezo electric load cell.
3. The device as claimed in claims 1 and 2, wherein said mounting means is provided with a taper bracket on which said load cell is positioned.
4. The device as claimed in any of the preceding claims wherein the display unit consists of converters and amplifiers to convert and amplify the load signals received from the load cell to digital signals for display.

5. A device for measuring and calitrating the load of top arms of spinning machines substantially as herein described and illustrated.