FIELD OF THE INVENTION

The present invention relates to an improved top arm arrangement of a textile machine especially for the roller drafting systems used in textile processing machines.

More particularly this invention focuses to have better handling of top arms while loading and unloading of top arms along with top rollers onto the steel bottom fluted rollers.

BACKGROUND OF THE INVENTION

In the typical yam manufacturing process, roller drafting system consists of multiple pairs of rollers, each pair rotating at a successively faster speed, for attenuating the fiber strand. Said multiple pair of rollers referred as steel bottom rollers and rubber covered top rollers. The steel bottom rollers usually of three or four are extended across the length of the machine from one end to the other and driven through gears. These bottom rollers along with its bearings are supported over the roller stands, arranged in a predetermined inclined angle referred as drafting angle.

The top arms are provided above the bottom rollers, with the top rollers being fixed on their lower side. The lower side of each top arm is provided with three top rollers, i.e. front, middle and back rollers which make pair with bottom front, middle and back rollers respectively. The said top rollers are covered with rubber cots. During operative condition, the said top arms provide loading action on the slivers / rovings which pass in between the top and bottom rollers. The top arms are also called as guide arms or weighing arms, assist the drafting process in order to convert slivers into rovings in roving frames and to convert rovings into yarns in spinning frames. In textile roving and spinning frames, single top arm serves for two spindles. The total number of top arms in a machine frame is equal to half the number of spindles.

The weighing action of said top arms is provided either by means of spring or pneumatic loading systems. The loading elements of above said top arms are distinguished according to suit with the spring or pneumatic loading systems. In the above said spring and pneumatic loading systems, the top arms are releasably maintained either in its operative position or in nonoperative position according to the requirement. To maintain the top arm in operative position, a locking lever extending over the top arm is pressed downward till it touches body of top arm to apply a nip pressure to the top rollers. Similarly to keep the top arm in nonoperative position, the locking lever is raised to a position so that the top rollers are supported at a spacing upwardly from its pair of bottom rollers. The top arm arrangement is configured such that an operator can lift the locking lever to raise the top arm from their operative position.

The top arm arrangement may be either spring or pneumatic loading systems, supported over a shaft or hexagonal guide tube which is positioned rearwardly to the drafting unit. According to the prior art as shown in Figure-1 and 1a, a top arm arrangement (1) for a textile drafting unit commonly used in textile machines has three bar linkage mechanism constitutes the fixed member (2), second member (3) and the third member (4). The fixed member (2) is a fixing element herein after called as setting piece, used to hold the individual top arms in their respective places over guide tube (5). The second member (3) of top arm assembly (1) in form of a U channel sheet metal arm extends towards machine front herein after called as Guide U. The Guide-U (3) having provision to fix the front and rear distributors (not shown) which carries the top roller saddles (not shown) with it. Usually the top rollers (not shown) are held in top roller saddles arranged in predetermined distances so as to make pair with the bottom rollers (not shown).

By using a pivot pin (7), the pressure thumb (6) is actively pivoted to the setting piece (2). The pressure thumb (6) is a solid block acts as a loading member during operative position, having one end interacts with the compressed air filled hose kept inside tube (5) and the other end participates in providing loading pressure to the top arms. The third member (4) herein after called as locking lever includes a free end portion (10) provided with a cover (10a), and an interconnecting end portion (11) provided with a cylindrical roller (12) and a pivot axis (13). The locking lever (4) assembly along with its parts is pivotally connected with said guide U (3) about the pivot axis (13). The pressure thumb (6) front end portion engages with the cylindrical roller (12) there by with the locking lever (4) at it's bulged portion (8) and followed by a seat part(9). When the top arm assembly is operated from its nonoperative (1a) to operative position (1) using this locking lever (4) desired loading pressure in top arms could be achieved. To keep in operative position (1), the locking lever (4) is being lowered till it rests on guide-U (3) to load the top arms so that the top rollers are cooperatively engaged with respect to their associated bottom rollers to form nips. Similarly to keep in nonoperative position (1a), the locking lever (4) is being raised away from the guide-U (3) so that the top rollers are supported at a spacing upwardly from their respective associated bottom rollers. The third member such as locking lever (4) acts as a connecting member between the fixed member such as setting piece (2) and the second member such as guide U (3).

In the known process of loading as shown in Fig.1, when the locking lever (4) is lowered and pressed till it rests on guide-U (3), the cylindrical roller (12) slides on pressure thumb (6), at the bulged portion (8) and finally reaches the seat part (9) of it and the desired loading of top rollers is being obtained. Similarly in the process of unloading as shown in Fig. 1a, when the locking lever (4) is lifted away from guide U (3), the roller (12) departs from its seat part (9) and slides about the bulged portion (8) and finally the top arm is being unlocked. Generally this loading and unloading of top arm requires ample force which is given by manual intervention. Though it looks simple, it is a difficult task when doing it for so many number of working positions, and particularly it is relatively tough to the female operators, which increases fatigue.

Hence to overcome the above disfavours, it is necessary to provide a refined design of top arms which is convenient in handling compared to the prior art systems.

OBJECTS OF THE INVENTION

It is an object of the invention to provide an improved top arm when compared to prior art systems.

It is further object of the invention to provide a refined top arm design for better handling convenience particularly to young and female operators compared to prior art systems.

It is yet another object of the invention to provide top arms which are superior in performance, comfort, user friendliness compared to prior art systems.

SUMMARY OF INVENTION

According to the invention, the improved top arm assembly comprising necessary common elements such as guide U, setting piece, hexagonal guide tube and a locking lever along with its cylindrical roller. An extended portion of the setting piece is provided with a cylindrical roller thereby cooperatively engage/disengage with the cylindrical roller arranged at locking lever, during their respective operative and nonoperative positions. The sliding nature of the above cylindrical rollers enables smooth handling function of top arms during their operation between respective operative and nonoperative positions. Alternatively any rolling members in place of said cylindrical rollers can be used, for example bearings.

In the process of loading, when the locking lever is pressed, the cylindrical roller associated with the locking lever rolls around the periphery of the cylindrical roller of the setting piece and stops when the locking lever rests on guide-U. Similarly during unloading process, when the locking lever is lifted away from the guide-U, the cylindrical roller associated with the locking lever tends to slide from its stopped position, around the periphery of the cylindrical roller of setting piece and finally the top arm is being unloaded. The function of the twin rollers arranged in this improved top arm assembly is simple and provides easy and smooth handling of top arms.

From the studies done between with existing top arm and top arm according to this invention, it is found that the handling is very easy and the force required to locking lever the new top arm is around 50% less, when compare to the existing top arms.

Benefits of this invention that the top arm is of simple in construction, reduction in wear and tear thus long life, gentle in operation, comfort and user friendliness, performance and good quality.

BRIEF DESCRIPTION OF THE DRAWING

Fig.1 schematically illustrates the prior art top arm arrangement of a textile machine during operating position.

Fig. 1a schematically illustrates the prior art top arm arrangement of a textile machine during nonoperative position.

Fig.2 schematically illustrates the present invention of improved top arm arrangement of a textile machine during operating position.

Fig.2a schematically illustrates the present invention of improved top arm arrangement of a textile machine during nonoperative position.

BRIEF DESCRIPTION OF THE INVENTION

According to the invention shown in Fig.2 and 2a illustrates an improved top arm (51) arrangement used for textile yarn spinning and roving processing machines. The said top arm (51) arrangement is having three bar linkage mechanism with links named as fixed member (52), second member (53) and third member (54).

The fixed member (52) is a fixing element herein after called as setting piece, used to hold the individual top arms in their respective places over guide tube (55). As per the invention, the setting piece (52) is provided with an extended profile (56) along with a cylindrical roller (57) rotating about an axis. The extended profile (56) acts as one of the loading elements of this invention, in which the cylindrical roller (57) is employed in such a manner to work cooperatively engage / disengage with the roller (62) arranged in the third member (54).

The second member (53) is rotatably mounted about a pivot axis (58) with the setting piece (52) using pivot pin (59). The second member (53) of top arm assembly (51) is in form of a U channel sheet metal arm and extend towards machine front herein after called as guide-U. The guide-U (53) having provision to fix the front and rear distributors (not shown) which carries the top roller saddles (not shown) with it. Usually the top rollers (not shown) are held in top roller saddles arranged in predetermined distances so as to make pair with the bottom rollers (not shown).

The third member (54) herein after called as locking lever includes a free end portion (60), and an interconnecting end portion (61) with a cylindrical roller (62). The locking lever (54) along with its cylindrical roller (62) is pivotally connected with said guide U (53) about an axis (63). The rotational sliding nature of said cylindrical rollers (57, 62) cooperatively engaged in smooth handling function of top arms during the operation of locking lever (54) between operative (51) and nonoperative positions (51a). As per this invention, the fixed member (52), guide U (53) and locking lever (54) are pivotally connected with each other during operative and non operative positions, inwhich rollers (57, 62) are provided in fixed member (52) and locking lever (54). The cylindrical rollers (57, 62) are rotatably mounted in fixed member (52) and in locking lever (54) respectively.

In the process of loading, when the locking lever (54) is lowered and pressed till it rests on guide-U (53), the cylindrical roller (62) associated with the locking lever (54) smoothly rolls together with the cylindrical roller (57) of the setting piece (52). Similarly during unloading process, when the locking lever (54) is lifted away from the guide-U (53), the cylindrical roller (62) at the locking lever (54) rolls back together with the cylindrical roller (57) of setting piece (52) and finally the top arm (51) is being unloaded. The twin rollers (57, 62), arranged in top arm assembly (51) is very simple to have easy and smooth handling of top arms (51). This together rolling action of rollers (57, 62) enables friction free movement during loading and unloading of top arm (51) during the operative (51) and nonoperative positions (51a).

Although the present invention has been fully described in connection with the preferred embodiment thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are possible and are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims.

WE CLAIM:

1. A top arm arrangement of a textile machine comprising fixed member, guide U, locking lever pivotally connected with each other during operative and non operative positions, wherein rollers (57, 62) are provided in fixed member (52) and locking lever (54)

2. Atop arm arrangement of a textile machine as claimed in claim 1, wherein cylindrical roller (57) is rotatably mounted in fixed member (52) and cylindrical roller (62) is rotatably mounted in locking lever (54),

3. A top arm arrangement of a textile machine as claimed in claim 1 wherein the cylindrical rollers (57, 62) roll around the periphery of each other during loading and unloading of locking lever (54)