Process and apparatus for monitoring the efficiency of a ring spinning machine

Abstract

In order to monitor the efficiency of a ring spinning machine, the doffed bobbins are analyzed with respect to their weight and/or appearance during their transport away from the machine. The bobbins are preferably transported away on peg trays, which are guided past a weighing device connected to the machine.

Description

BACKGROUND AND SUMMARY OF THE INVENTION

[0002] This application claims the priority of German application 198 51 007.1, filed in Germany on Nov. 5, 1998, the disclosure of which is expressly incorporated by reference herein.

[0003] The present invention relates to a process for monitoring the efficiency of a ring spinning machine, which is connected to a machine computer, and on which machine the spun bobbins of at least one machine side are collectively doffed.

[0004] The system from USTER is the most well known for monitoring the efficiency of a ring spinning machine. It can, with the aid of the USTER mouse, be ascertained, whether a traveller movement is present or not, from which then end breaks can be deduced.

[0005] It is an object of the present invention to monitor the efficiency of a ring spinning machine in a significantly simpler way.

[0006] This object has been achieved in accordance with the present invention in that each single spun bobbin is analyzed with regard to its weight or appearance while it is being transported away from the spinning machine, and the results are fed to the machine computer.

[0007] The present invention is based on the knowledge that a bobbin, which comes from a spinning station subject to end breaks, weighs less on the one hand, and on the other hand has a somewhat changed form. From German published patent application 42 11 985 it is known that the weight and the appearance of a bobbin are checked subsequently. In prior art, however, no conclusions are drawn from the spinning process, rather the check serves only the preparation of the bobbin for further processing. The present invention goes one step further and passes on the acquired data to the machine computer, which independently monitors the efficiency and, if required, ascertains also the amount produced.

[0008] In a preferred embodiment of the invention it is provided that the bobbins are transported away on peg trays, and that the peg trays are guided past a weighing device which is connected to the spinning machine.

[0009] The peg trays are hereby weighed together with the bobbins. The known weight of the peg trays and tubes can then be substracted, which gives the weight of the yarn. Possible occurring variations in the weight of the tubes and the peg trays do not, statistically, have an effect on the analysis in practice. As the peg trays are, as a rule, delivered away from the machine in sequence, a short rest phase occurs for each individual peg tray, which rest phase is sufficiently long to permit a weighing process to take place. For example, a weighing device, as is known in principle from prior art, can be applied to the machine end. What is important in the process is that each individual bobbin is clearly related to a spinning station, which can be achieved easily with the aid of the computer.

[0010] other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIG. 1 schematically depicts the system and apparatus for carrying out the monitoring of yarn bobbins and controlling a ring spinning machine, constructed in accordance with preferred embodiments of the present invention; and

[0012] FIG. 2 is a schematic part sectional view of a bobbin weighing station constructed according to a preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 schematically depicts the method and apparatus of the present invention.

[0014] The ring spinning machine 1 produces bobbins 2 of yarn which are transported by transport device 3 (depicted with arrows) away from the machine 1. The individual bobbins 2 are placed in peg trays 4 which are sequentially moved through a weigh station 5. At weigh station 5, the peg trays 4 are weighed and a weight signal 6 is transmitted to a control computer 7 which controls the operation of the spinning machine 1.

[0015] The control computer 7 analyzes the weight signal 6, including adjustments for the weight of the peg tray 4 and the tubes of the bobbins. The computer 7 associates the weight signal 6 with respective spinning stations of the spinning machine 1 and uses this information to produce a feedback control signal 8 to the spinning machine 1.

[0016] FIG. 1 also indicates alternative arrangements for individually weighing the bobbins 2. Weigh station 9 schematically depicted in dash lines includes a corresponding individual bobbin weight signal 10 transmitted to the computer control 7.

[0017] Also shown in dash lines in FIG. 1 is a bobbin appearance detector 11 for detecting the appearance of respective individual bobbins and generating a bobbin appearance signal 12 supplied to the control computer 7. Either or both of the arrangements for generating individual bobbin weight and appearance signals can be used to provide the computer control 7 with information concerning the status of individual bobbins as they are transported from the spinning machine 1, and to generate corresponding control signals 8 for respective individual spinning stations producing the respective bobbins.

[0018] FIG. 2 illustrates a preferred embodiment of a weighing device constructed such that it weighs the spinning spools or cops together with the transporting device peg tray plates. A spinning spool 2 or cop consists of a tube 13 onto which yarn layers 14 are wound. On a ring spinning frame, a plurality of the spinning spools or cops 2 are produced on each frame side which are then all doffed simultaneously. During this doffing, the spools or cops 2 with the tubes 13 are fitted onto pegs 17 of plates 16 which together form a so-called peg tray 4. The cops are transported away from the ring spinning frame by means of the peg trays 4.

[0019] The cops 2 are transported in the direction of the arrow A, being slidingly displaced, for example, on a rail 20. A recess is provided in the rail 20. A lifting plunger 19 can be moved out of the recess and acts with a known constant force F from below against a plate 16 of the peg tray 4 and lifts this peg tray plate 16 together with the cop 2 upwardly from position 15. A bow 24 of a lever arm 21 of a scale 18 is applied to the top side of the plate 16 of the peg tray 4. The lever 21, which can be swivelled about an axis 23, is provided with another arm to which a force measuring device M is applied. The force measured here, while taking into account the lever arms, corresponds to the force F minus the weight of the cop 2 and of the peg tray plate 16. Because the weight of the peg tray plate 16 and the tube 13 is known, the weight of the cop 2 can be computed. As described above, the cops 2 with the peg trays 4 are transported in a timed manner. A measuring of the weight can therefore take place during a short stoppage time during the transport. With peg trays having rows of plates 16 and pegs for accommodating rows of cops, corresponding recesses R can be provided in the rail 20 to accommodate respective plungers 19 and levers 21 to facilitate the weighing operation. This weighing device provides an output signal (signal 6 or 10) from the respective weight station (5 or 9) to the computer control 7 to be processed as described above.

[0020] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.

Claims

1. A process for monitoring the efficiency of a ring spinning machine connected to a machine computer, on which machine the spun bobbins of at least one machine side are collectively doffed, wherein, during transport away from the ring spinning machine, each individual bobbin is analyzed with respect to its weight and/or appearance, and wherein the results are transmitted to the computer to be processed and used to control operation of the individual spinning stations producing the respective bobbins.

2. A process according to claim 1, wherein the bobbins are transported away on peg trays and the peg trays, carrying the bobbins, are guided over a weighing device connected to the spinning machine.

3. A process for monitoring efficiency of a ring spinning machine producing spun bobbins at a plurality of spinning stations, comprising analyzing each bobbin with respect to at least one of its weight and appearance as the bobbins are transported away from the machine and transmitting results of said analysis to a control computer of the spinning machine to be processed and used to control operation of the individual spinning stations producing the respective bobbins.

4. A process according to claim 3, wherein the bobbins are transported away on peg trays and the peg trays, carrying the bobbins, are guided over a weighing device connected to the spinning machine.

5. A process according to claim 3, wherein said analyzing includes weighing said bobbins.

6. A ring spinning system comprising: a plurality of spinning stations for producing spun yarn packages, a doffing system for removing the spun yarn packages, a transport system downstream of the doffing system for transporting the spun yarn packages away from the spinning machine, and an analyzing system for analyzing each yarn package with respect to at least one of its weight and appearance as the yarn packages are transported away from the machine and transmitting results of said analysis to a control computer of the spinning machine to be processed and used to control operation of the individual spinning stations producing the respective bobbins.

7. A ring spinning system according to claim 6, wherein the bobbins are transported away on peg trays and the peg trays, carrying the bobbins, are guided over a weighing device connected to the spinning machine.

8. A ring spinning system according to claim 6, wherein said analyzing includes weighing said yarn packages.

9. A ring spinning system according to claim 7, wherein said peg trays are carried on a traveling member which includes a recess, and wherein said weighing device includes a force applying member selectively movable in said recess to temporarily lift a bobbin carrying plate of the peg tray during weighing operation.

10. A weighing device for weighing yarn wound on bobbins during transport of said bobbins away from a spinning machine on respective peg trays carried by a moving conveyor member, comprising: a recess in said conveyor member disposed in use under an individual peg tray plate with a peg supporting a bobbin thereon, a plunger selectively movable into the recess to lift the tray plate and bobbin with a predetermined lifting force, a lever engageable with the tray plate acting against lifting movement thereof, and means applying a measuring force to the lever.

11. A weighing device according to claim 10, wherein the lever is a two armed lever which is pivotally supported intermediate the arms thereof, one arm engaging the tray plate and the other arm being acted on by the measuring force.