CN1140657C - Projectile shuttle and device for picking up the weft thread - Google Patents

Abstract

The gripper comprises a housing (1), a clamping part (5) what a hook-like clamping section (12) receiving a weft yarn and a clamping unit (6) with a clamping tongue (22), a torsion bar (23) and a cover plate (7). The clamping tongue (22) is pivotable, cooperates with the clamping section (12) and is influenced by the torsion bar (23) in order to clamp the weft yarn. The clamping force is applied by the torsion bar (23) and the effect of the clamping is neutralized by the cover plate (7). One advantage of the gripper is that it consists of a minimum number of parts. Another advantage is that it is extremely compact.

Description

Projectile shuttle and device for picking up the weft thread

The invention relates to a projectile according to the preamble of claim 1 and a device for picking up weft threads as well as a weaving machine with such a device.

Projectiles with yarn clamps of different configurations are known. The yarn clamp is mainly composed of a fixed clamping part, a movable clamping part, a spring element and an operating mechanism, the difference lies in the clamping form and clamping movement.

For a gripper, the fixed clamping part consists of a housing with a hook-shaped clamping section for receiving the weft thread, while the movable clamping part consists of a clamping tongue, which rests on the helical spring Under the action, it can move longitudinally along the housing and is used to clamp the weft yarn. An actuating mechanism is connected to the clamping tongue for guiding the movement of the clamping tongue in the housing against the action of a spring.

For another projectile, the fixed clamping part consists of a housing with a hook-shaped clamping section for receiving the weft thread, while the movable clamping part consists of a clamping lever which can be Under the action of the spring, it rotates around an axis extending perpendicularly to the longitudinal direction of the housing, so as to clamp the weft yarn.

The use of helical springs has proven to be disadvantageous, since space and means are required for fixing and/or guiding the helical springs.

A kind of gripper shuttle of the above-mentioned type of the present invention is disclosed by German patent document DE-B-1 087 088. In this projectile, a torsion spring is formed by a helical spring and is arranged on a rotatable shaft part with clamping tongues. The torsion spring is supported on the housing part via a first protruding spring arm and on a positioning pin connected to the rod part via a second protruding spring arm and thus imparts a spring torque to the rod part. This design requires a lot of construction space transversely to the axis of the shaft, which therefore restricts the necessary small and elongated design of the gripper. The spring force of the torsion spring cannot be adjusted.

The object of the present invention is to improve grippers of the above-mentioned type.

The object of the invention is achieved by the features of claim 1 .

The achievable advantages of the invention are mainly that the gripper has a minimum number of individual parts and is of very compact construction, requires only little construction space transversely to the axis of the shaft part, and can work with low clamping forces, In addition, the clamping force can be adjusted.

The device according to the invention for picking up weft threads is characterized by the features of claim 8 .

The invention is described below with the aid of figures.

In the attached picture:

Figure 1 is a view of a gripper according to the invention;

Fig. 2 is the cross-sectional view obtained by sectioning the cutting shuttle along the section line II-II in Fig. 1;

Fig. 3 is the view of the projectile along the arrow D in Fig. 1;

Fig. 4 is the sectional view obtained by sectioning the cutting shuttle along the cutting line IV-IV in Fig. 1;

Fig. 5 is a sectional view obtained by sectioning the cutting shuttle along the cutting line V-V in Fig. 1;

Fig. 6 is a sectional view obtained by cutting the scissor along the section line VI-VI in Fig. 1 .

In FIGS. 1 and 2 the gripper 1 and part of the gripper belt 2 are shown. The gripper 1 has a housing 4 , a clamping part 5 , a clamping unit 6 and a fishplate 7 for actuating the clamping unit.

The housing 4 is made of plastic and has a bore 8 for receiving the clamping unit 6 . The clamping part 5 is made of metal and is connected to the housing 4 .

The clamping part 5 has a section 11 for fixing on the housing 4, a hook-shaped clamping section 12 for receiving the weft thread and an attachment 13 which overlaps the shuttle bar belt 2 so that when the weft thread is picked up Prevent damage to the warp yarn when threading. The hook-shaped clamping section 12 is provided with clamping surfaces (not shown). A hole 14 is formed in the hook-shaped clamping section.

The clamping unit 6 comprises a tubular shaft part 21 , a clamping tongue 22 and a torsion rod 23 which is arranged in the shaft part and is connected at one end to the shaft part 21 via a pin 24 . The shank part 21 has two annular shoulders 25 for supporting the shank part 21 on the fishplate 7 . The clamping tongue 22 is provided with a connecting part 26 which is connected to the shaft part at one end and has a guide pin 27 at the other end. The clamping tongue 22 is adjacent to the guide pin 27 and is connected to the connecting part 26 in such a way that the clamping tongue 22 protrudes radially beyond the connecting part 26 . The clamping unit has a sleeve 28 with a tool engagement hole 29 , which is fastened on the other end of the torsion bar 23 in such a way that the engagement hole is freely accessible. The sleeve 28 is arranged rotatably in the bore 8 of the housing 4 and is connected to the torsion bar 23 via a pin 30 . This sleeve 28 is also used to secure the clamping unit 6 in the housing 4 .

In FIGS. 3 and 4 , clamping surfaces 33 , 34 are provided on the hook-shaped clamping section 12 and clamping tongue 22 at 45° each and are provided with grooves 35 . This has the advantage of increasing the clamping surface or increasing the number of grooves, so that the clamping length of the weft yarn 36 is extended, the friction is increased and the clamping force can be reduced to prevent damage to the weft yarn.

As shown in FIG. 5 , the fishplate 7 for manipulating the clamping part 5 is connected to the rod part 21 by clamping. A screw 37 is provided for this purpose.

As shown in FIG. 6 , a clamping block 41 and a screw 42 are arranged inside the housing 4 for securely clamping the sleeve 28 . As already mentioned, the clamping unit 6 is fixed in the housing 4 by using a sleeve 28 .

In general, the clamping force is adjusted according to the characteristics of the weft yarn. For this purpose, the clamping effect on the sleeve 28 can be canceled by loosening the screw 42 and the sleeve 28 can be rotated by means of a tool (not shown). This rotational movement turns the clamping tongue relative to the hook-shaped clamping section 12 . The clamping action of the sleeve 28 can then be restored by tightening the screw 30 .

When picking up the weft thread, the fishplate 7 is moved by an actuator (not shown) arranged on the gripper guide rail and thereby the clamping tongue 22 is rotated relative to the hook-shaped clamping section 12 and the weft thread Clamped in the hook-shaped clamping section. The resetting of the clamping tongues takes place on the basis of the elasticity of the clamping unit 6 .

Claims (9)

1. A gripper for picking up a weft thread, comprising a housing (1), a clamping part (5) with a hook-shaped clamping section (12) for receiving a weft thread, a The rotatable clamping tongue (22) that the clamping section interacts and an actuating mechanism (7) for the clamping tongue, the clamping tongue is connected with the rotatable shaft part (21) and is supported by the torsion spring (23 ) under the action of clamping the weft yarn, it is characterized in that the torsion spring is made of a torsion bar spring (23) and is concentrically arranged in the bar body part of the tubular structure, wherein one end of the torsion bar spring (23) is connected to the bar body The part ( 21 ) is connected in a rotationally fixed manner and the other end is connected to the housing via an adjusting element ( 28 ; 41 , 42 ) for adjusting the clamping force of the clamping tongue. 2. The gripper according to claim 1, characterized in that the torsion bar spring (23) is guided or supported in the region of the hook-shaped clamping section (12). 3. Projectile according to claim 1 or 2, characterized in that the hook-shaped clamping section (12) and the clamping tongue (22) each have a clamping surface with a groove (35) (33, 34). 4. The gripper according to claim 3, characterized in that the clamping surfaces (33, 34) are arranged at approximately 45° relative to the hook strip (2). 5. The gripper according to any one of claims 1 to 4, characterized in that a connecting part (26) rotatably supported in the housing is connected to the rod part (21) and supports the clamping tongue ( twenty two). 6. Projectile according to claim 5, characterized in that the connecting part (26) is guided or supported in the region of the hook-shaped clamping section (12). 7. Projectile according to claim 1, characterized in that the actuating mechanism (7) of the clamping tongue (22) is fixed on the shaft part (21). 8. A device with a shuttle bar belt (2) and with a gripper as described in any one of the preceding claims for picking up a weft yarn, is characterized in that the housing (4) is fixed on the shuttle bar belt ( 2) The upper clamping part (5) has an attachment (13) that overlaps the shuttle bar band (2). 9. A loom having a device as claimed in claim 8.

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