FIELD OF THE INVENTION

The present invention relates to an apparatus for detecting the position of gripper beam in a textile machine.

More particularly, this invention relates to an apparatus used to identify the position of gripper beam in a textile ring spinning and twisting machine.

BACKGROUND OF THE INVENTION

In a textile ring spinning and twisting machine, autodoffer is provided with gripper beams with plurality of grippers for gripping and releasing the individual conical tubes/cops as the case may be. The individual grippers being uniformly spaced from one another at the same spacing as the spindle spacing and are mounted on the gripper holder attached to the gripper beam. The said gripper beam is held by a scissor type member which is mounted over a lift axis shaft. The said scissor type member is provided with means for vertically and laterally moving the gripper beam to perform the doffing operation. The laterally moving means being operable to move the gripper beam laterally towards and away from the row of spindles during gripping engagement of the conical tube/cop by the individual gripper. The vertically moving means being operable to raise and lower the gripper beam during the gripping engagement of the conical tube/cop by the individual gripper.

During doffing, if the gripper beam has to be moved to predetermined positions for performing its function of removing the full cop from the spindle and replacing it with empty cop, it is necessary to provide an efficient detecting arrangement to identify the position of gripper beam ensuring normal working condition.

In known type of doffing, a motor is employed to drive the screw rod/lift axis shaft. A proximity sensor is fitted in the vicinity of screw rod, i.e. lift axis shaft. The proximity sensor is faced towards a wheel, which is mounted on a nut/sprocket means, which rotates around the screw rod in the lift axis shaft. Upon longitudinal movement of the lift axis, the wheel rotates over the screw rod. The said wheel rotations are transformed into pulses, which are detected by said proximity sensor. Based on the number of pulses generated, the position of gripper beam is identified. The disadvantage in this type is that, there are chances for backlash between the said wheel, nut/sprocket means and the screw rod. This will result in variation of pulse generation by the proximity sensor, which leads to improper position detection by the doffer control device. The level of accuracy in this type of system is very low since the proximity sensor senses the wheel but not the gripper beam directly. The gripper beam position detection in this arrangement is indirect and not intelligent.

It will be advantageous if the detecting apparatus identifies the position of gripper beam directly in an accurate manner. In the proposed arrangement, the detecting apparatus is fixed in the lift axis shaft and detects the position of gripper beam in a direct and intelligent manner. The detecting apparatus used for said arrangement is preferably an ultrasonic sensor.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide an improved and reliable detecting apparatus to identify the position of gripper beam in textile ring spinning and twisting machines.

It is another object of the invention to provide an accurate position detecting arrangement for the gripper beam in textile ring spinning and twisting machines.

It is yet another object of the invention to eliminate the usage of proximity sensor and wheel for detecting the position of gripper beam thereby reducing the number of components.

It is another object of the invention to identify the position of gripper beam in a direct and intelligent manner.

It is yet another object of the invention to minimize the idle times arising due to unexpected obstructions to the gripper beam movement and thereby improving the production efficiency of textile ring spinning and twisting machines.

SUMMARY OF THE INVENTION

According to one aspect of this invention, there is provided an apparatus for detecting the position of gripper beam in a textile machine wherein at least a sensing means is provided to directly detect the target means.

Another aspect of this invention is a textile ring spinning and twisting machine. The ring spinning and twisting machine comprises an autodoffer; said autodoffer provided with a gripper beam; said gripper beam provided with plurality of grippers; characterized in that at least a sensing means is provided to directly detect the target means. The detecting apparatus used for said arrangement is an ultrasonic sensor. The ultrasonic sensor is fixed at the lift axis shaft region, ensuring accurate position of the gripper beam in a direct and intelligent manner. The detected signal is fed to the doffing motor, which in turn controls the position and movement of the gripper beam.

According to another aspect of this invention, it eliminates the usage of proximity sensor and wheel which detects the position of gripper beam indirectly.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 indicates a known type of detecting arrangement using proximity sensor for identifying the position of gripper beam in textile ring spinning and twisting machines.

Figure 2 indicates a preferred embodiment of the present invention using ultrasonic sensor for identifying the position of gripper beam in textile ring spinning and twisting machines.

Figure 3 indicates an alternate embodiment of the present invention using ultrasonic sensor for identifying the position of gripper beam in textile ring spinning and twisting machines.

DETAILED DESCRIPTION OF THE INVENTION

The invention may be better understood and the further advantages and uses thereof more readily apparent, when considered in view of the following detailed description of exemplary embodiments, taken with the accompanying drawings. These embodiments describe only a few of the various ways in which the principles of various other embodiments may be realized and the described embodiments are intended to include all such embodiments and their equivalents and the reference numerals used in the accompanying drawings correspond to the like elements throughout the description.

Referring to figure 1, in a known type of position detecting arrangement, autodoffer in a ring spinning and twisting machine is provided with a gripper beam (1) with plurality of grippers (2) for selectively gripping and releasing an individual conical tube/cop (not shown). The gripper beam (1) is mounted with a support member (3) of scissor type linkage member, which possesses a long link (4) and a short link (5). One end of the long link (4) is swingably connected to the said support member (3) of the gripper beam (1). The other end of the long link (4) is swingably connected to a sliding support member (7) mounted over the lift axis shaft (8). One end of the short link (5) is swingably connected to the long link (4) at the center of the latter. The other end of the short link (5) is swingably connected to a fixed support member (6) over the lift axis shaft (8). A nut/sprocket means (11) along with the wheel (12) is mounted around the screw rod (9) extending along the lift axis shaft (8). During the movement of gripper beam (1), said screw rod (9) and nut/sprocket means (11) along with the wheel (12) rotates. A proximity sensor (10) which is located in the vicinity of the wheel (12) as shown in figure 1, detects the pulses generated from said wheel (12) rotation. Based on the number of pulses generated, distance (A) between the fixed support member (6) and sliding support member (7) is calculated. This, in turn is used to identify the position of the gripper beam (1). There are chances for backlash between the said wheel, nut/sprocket means and the screw rod in this method which will result in variation of pulse generation by the proximity sensor. This will result in improper position detection by the doffer control device. To overcome said disadvantages, the present invention employs an ultrasonic sensor (13) for improved position detection of gripper beam (1), as shown in figures 2 and 3.

Referring to figure 2, in a preferred embodiment of this invention, a target means (14) is rigidly fitted below the sliding support member (7) of the lift axis shaft (8). The target means (14) may include any downwardly projecting member which is sensible to ultrasonic signals. The ultrasonic sensor (13) is rigidly fitted below the lift axis shaft (8) at a predetermined distance from the target means (14). The said ultrasonic sensor (13) is fitted so as to directly detect the signal and determine the variable distance (A) in between the fixed support member (6) and the sliding support member (7). The signal generated by the ultrasonic sensor (13) is processed and fed to the doffing motor (not shown) and in turn used to identify and control the position of gripper beam (1).

Figure 3 describes another embodiment of this invention in which, the target means (14) is rigidly fitted below the support member (3) of the gripper beam (1). In this embodiment, the target means (14) may include any downwardly projecting member sensible to ultrasonic signals or the gripper beam (1) itself may act as target means (14). The ultrasonic sensor (13) is rigidly fitted to the fixed support member (6) of the lift axis shaft (8) so as to directly detect the signal from the target means (14). The variable distance (A) in between the support member (3) and the fixed support member (6) is detected by the said ultrasonic sensor (13). The signal generated by the said ultrasonic sensor (13) is processed and fed to the doffing motor (not shown) and in turn used to identify and control the position of gripper beam (1).

The ultrasonic sensor (13) disclosed in this invention ensures a more accurate position detection compared to the existing apparatus known in the art. This type of position detection is simple, direct and intelligent. Further the production efficiency of the textile ring spinning and twisting machine is enhanced with the usage of the apparatus disclosed in this invention.

In view of the present disclosure which describes preferred and best modes for detecting the position of gripper beam, many modifications and variations would present themselves to those skilled in the art without departing from the scope and spirit of this invention. All types of sensors such as photo sensor, optical sensor, light sensor, transmitters and receivers and other sensors performing the described function are still comprised within the true spirit of the invention. All changes, modifications and variations coming within the meaning and range of equivalency are considered within the scope.

We claim:

1. An apparatus for detecting the position of gripper beam (1) in a textile machine wherein at least a sensing means is provided to directly detect the target means (14).

2. An apparatus for detecting the position of gripper beam (1) in a textile machine as claimed in claim 1, wherein said sensing means is preferably an ultrasonic sensor (13).

3. An apparatus for detecting the position of gripper beam (1) in a textile machine as claimed in claim 1, wherein said target means (14) is a downwardly projecting member sensible to ultrasonic signals.

4. An apparatus as claimed in claim 2, wherein said ultrasonic sensor (13) is rigidly fitted below the lift axis shaft (8) at a predetermined distance from the target means (14) so as to detect the signal directly from said target means (14).

5. An apparatus as claimed in claim 3, wherein said target means (14) is rigidly fitted below the sliding support member (7) of the lift axis shaft (8).

6. An apparatus as claimed in claim 2, wherein said ultrasonic sensor (13) is rigidly fitted to the fixed support member (6) of the lift axis shaft (8) so as to detect the signal directly from said target means (14).

7. An apparatus as claimed in claim 3, wherein said target means (14) is rigidly fitted below the support member (3) of the gripper beam (1).

8. A textile ring spinning and twisting machine comprising an autodoffer;

said autodoffer provided with a gripper beam (1);

said gripper beam (1) provided with a plurality of grippers (2);

characterized in that at least a sensing means is provided to directly detect
the target means (14).

9. A textile ring spinning and twisting machine as claimed in claimed 8, wherein said sensing means is preferably an ultrasonic sensor (13).

10. An apparatus for detecting the position of gripper beam in a textile machine substantially as herein described with reference to the accompanying drawings.