JP3425984B2 - Dobby - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dobby used for weaving by a loom, and more particularly to a dobby for electromagnetically controlling a heddle frame to be moved up and down.

[0002]

2. Description of the Related Art A dobby for electromagnetically controlling a heddle frame to be moved up and down generally includes a vertical lever connected to the heddle frame, a connecting hook pivotally attached to the vertical lever and a connecting hook. And a knife hook that is periodically moved away from each other, and the knife hook is selectively displaced into a first position that is not engageable with the connecting hook and a second position that is engageable with the connecting hook. A swingable command lever to be controlled, a swingable pusher to control the position of the command lever, and a swing to displace the command lever to selectively displace the knife hook to the first and second positions. A plurality of actuating mechanisms including a movable selection lever and a magnet that releasably attracts the selection lever to selectively displace the knife hook to the first and second positions. Including (for example, Japanese fair 2-236
No. 11, Japanese Patent Publication No. 3-4658).

In the known dobby, one or more heald frames are connected to a vertical lever of each actuating mechanism via a link mechanism or the like. If the selection lever is not attracted to the magnet, the pusher is maintained in a position where it does not abut the command lever, whereby the knife hook is maintained in the first position where it cannot engage the connecting hook. On the other hand, when the selection lever is attracted to the magnet, the pusher is maintained in a position where it can contact the command lever, and in this state, the pusher is swung to push the command lever, which causes the knife hook to be connected. It is maintained in a second position engageable with the hook.

Even if the knife hook is moved while the knife hook is not engaged with the connecting hook, the vertical lever is not moved, so that one or more heald frames connected to the vertical lever are not moved. However, when the knife hook is moved while the knife hook is engaged with the connecting hook, the vertical lever is moved in one direction, so that the one or more heald frames connected to the vertical lever are moved.

The known dobby also includes a drive mechanism for periodically moving the selection lever toward the magnet in synchronism with the rotation of the main shaft of the loom in order to securely attract the selection lever to the magnet.

In a known dobby including a drive mechanism, the selection lever is attracted to the magnet if the magnet is energized when the selection lever approaches or contacts the magnet by the drive mechanism. Further, when the selection lever is not approaching or in contact with the magnet by the drive mechanism, the selection lever is not attracted to the magnet even if the magnet is energized. Further, if the selection lever is not close to or in contact with the magnet, the command lever will not be attracted to the magnet even if the magnet is energized.

For this reason, in the known dobby, the selection lever is not approaching or abutting the magnet at the start of the reverse rotation for the processing of the weaving mistake and the subsequent restart of the normal rotation. Even if the magnet is energized, the command lever is often not attracted to the magnet, and as a result, the warp cannot be placed in the correct open state according to the weave pattern at the start of reverse rotation and at the restart of normal rotation.

In order to solve such a problem, in a known dobby, a time zone in which the start of reverse rotation is prohibited (reverse rotation prohibition zone) and a time zone in which resumption of normal rotation is prohibited (normal rotation prohibition zone)
The ratio of the no-reverse zone and the no-normal zone to one weft insertion time was large.

[0009]

An object of the present invention is to reduce the reverse rotation prohibition band and the normal rotation prohibition band.

[0010]

SOLUTION: The dobby of the present invention is a first and a second hook which are relatively moved toward and away from each other, said first hook being connected to a heddle frame, A second hook pivotable between a first position disengageable with the first hook and a second position engageable with the first hook; Selectively between a third position that controls displacement of the second hook to the first position and a fourth position that controls displacement of the second hook to the second position. A displaceable first lever, a fifth position for controlling displacement of the first lever to the third position, and a displacement of the first lever for the fourth position A pusher capable of swinging movement to a sixth position, and the pusher including the pusher A second lever for selectively displacing the second lever, a magnet for releasably attracting the second lever to maintain the pusher in one of the fifth and sixth positions, and Lever 2
Drive means for periodically moving toward the magnet in synchronism with rotation of the main shaft of the loom and moving toward the magnet at the time of starting reverse rotation of the main shaft of the loom and resuming forward rotation . Lever and pusher
-One of the other is the other of the first lever and the pusher.
It has a cam-shaped contact surface with which one part abuts .

In the dobby of the present invention, one or more heald frames are connected to the first hook via a link mechanism or the like. If the second lever is not attracted to the magnet,
The pusher is maintained in either one of the fifth and sixth positions whereby the second hook is disengageable with the first hook and in the first position and with the first hook engageable with the first hook. It is maintained at either one of the two positions. On the other hand, when the second lever is attracted to the magnet, the pusher and the second hook are maintained at the other positions.

Therefore, even if the first or second hook is moved with respect to the second or first hook while the pusher is maintained at the fifth position, the second hook does not move to the first position. Since it does not engage with the hook, the first lever does not move, and the one or more heald frames connected to the first hook do not move.

When the pusher is displaced from the fifth position to the sixth position, the first lever is displaced from the third position to the fourth position. Thereby, the second hook is displaced from the first position to the second position.

When the second hook is moved while the pusher is maintained in the sixth position, the second hook engages with the first hook, so that the first hook moves to the second hook. The one or more heddle frames, which are moved together with the hook and connected to the first hook, are moved.

During the forward rotation and the reverse rotation, in synchronization with the rotation of the loom, the magnet is excited according to the weaving pattern, and the second lever periodically approaches or contacts the magnet by the driving means. Contacted. Therefore, the second lever is surely attracted to the magnet.

When the reverse rotation is started and the normal rotation is restarted, the second lever is brought close to or brought into contact with the magnet by the driving means. Therefore, if the magnet is in the excited state at the start of reverse rotation and at the time of restarting normal rotation, the second lever is attracted to the magnet, and as a result, at the start of reverse rotation and normal rotation, the second lever moves. It is placed in the correct condition according to the weave pattern.

According to the present invention, since the driving means for moving the second lever toward the magnet is provided at the time of starting the reverse rotation and restarting the normal rotation, the second lever is rotated in the correct state according to the weave pattern. forward rotation is started, also,
One of the first lever and the pusher of the other of these
Since the cam-shaped contact surface with which part of the contact is provided, the second relay
The first displacement caused by the displacement of the pusher due to the movement of the bar
The relative movement of the bar and pusher becomes smoother, resulting reversed and at the start of forward rotation, from being placed in the correct opening state warp corresponding to the weave pattern, due to reverse rotation prohibited band and forward forbidden band machining error or the like Can be set to the required small value.

The drive means includes a first drive mechanism for periodically moving the second lever toward the magnet in synchronization with the rotation of the main shaft of the loom, and the second lever for moving the second lever to the main shaft of the loom. It is preferable to include a second drive mechanism for moving the magnet toward the magnet at the start of reverse rotation and at the start of normal rotation. With this configuration, since a small magnet having a small attracting force can be used, it is possible to prevent the attracting force of the magnet from affecting the other second lever, and to correctly move the heddle frame. You can

In a preferred embodiment, a pair of said first hooks pivotally mounted on a third pivotable lever and arranged at opposite points with respect to the pivot center of said third lever, A pair of the second hooks that individually correspond to the first hooks and that can be engaged with the corresponding first hooks; and a second hook that individually corresponds to the second hooks and that correspond to the second hooks. A pair of the first levers for controlling, and the pusher controls both the first levers.

In a preferred embodiment, the first elastic body for exerting a force for displacing the second hook to the second position on the second hook, and the both first levers are further provided. A second elastic body that applies a force for displacing to the third position to the first lever, and a third elastic body that applies a force that allows the pusher to displace to the fifth position to the second lever. The first hook is maintained in the second position by the force of the first elastic body when the second lever is attracted to the magnet.

In another preferred embodiment,
An elastic body that acts on the second hook to displace the second hook to the second position, and a force that allows the pusher to displace to the fifth position on the second lever. And another elastic body to be operated, and the first hook is maintained in the second position by the force of the first elastic body when the second lever is attracted to the magnet. .

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, a dobby includes actuating mechanisms 10 each associated with one or more heald frames (not shown).

Each actuating mechanism 10 corresponds to a vertical lever 12 extending vertically, a connecting hook 14 pivotally attached to a pair of portions spaced apart in the longitudinal direction of the vertical lever, and the connecting hook individually. Knife hook 16, command lever 18 individually corresponding to the knife hook, and pusher 2 for displacing the command lever
0, a selection lever 22 that displaces the pusher, and a magnet 24 that releasably attracts the selection lever.

The vertical lever 12 is connected to one or more corresponding heddle frames via a link mechanism such as a jack lever 26. The jack lever 26 has a substantially C-shape. One end of the jack lever 26 is swingably supported by a shaft 28 extending in the horizontal direction, and the other end of the jack lever 26 is swingable to the center of the vertical lever 12 by a pivot 30 parallel to the shaft 28. Are linked to. The shaft 28 extends in a direction perpendicular to the paper surface in FIG.

Each connecting hook 14 is swingably attached to an end portion of the vertical lever 12 by a pivot 32 parallel to the shaft 28, and has a hook portion 14a engageable with the knife hook 16 at its tip portion. . The rear end surface of each connecting hook 14 is pulled to the left in FIG. 1 by a spring (not shown) connected to the corresponding heddle frame by the jack lever 26 and the vertical lever 12, so that a stopper parallel to the shaft 28 is formed. It is in contact with 34. Each connecting hook 14 is prevented from swinging around the axis of the pivot 32 while its rear end surface is in contact with the stopper 34.

Each knife hook 16 has a swing lever 38 extending in the vertical direction by a pivot 36 parallel to the shaft 28.
Is swingably arranged at the end of the. Swing lever 38
Is supported at its central portion by a swingable shaft 40 extending parallel to the shaft 28. Each knife hook 16 has a hook portion 1 of the corresponding connecting hook 14.
4a, and the hook portion 16a is urged by the elastic body 42 to a position where the hook portion 16a can be engaged with the hook portion 14a.

The shaft 40 is periodically rotated in the forward and reverse directions within a predetermined angular range in synchronization with the rotation of the main shaft of the loom, whereby the swing lever 36 is synchronized with the rotation of the main shaft of the loom. It is swung in the direction of arrow 41 in. Therefore, the two knife hooks 16 are alternately moved in a direction approaching the connecting hook 14 and away from the connecting hook 14 in a synchronized manner with the rotation of the main shaft of the loom, and are periodically moved in the opposite direction.

In the illustrated example, each elastic body 42 is engaged with the knife hook 16 and a stopper 44 that prevents the knife hook 16 from rotating more than a predetermined angle. The stopper 44 is fixed to the swing lever 38 or another member. In the illustrated example, the elastic body 42 is provided for each knife hook 16, but one elastic body may be commonly used by both knife hooks.

The command lever 18 is swingably supported by a pivot 46 extending in parallel with the shaft 28, and is arranged so as to oppose in the vertical direction and extend in the horizontal direction. The command lever 18 has a push portion 48 that pushes the corresponding knife hook 16 at one end, and has a so-called cam-shaped contact surface 50 that contacts the pusher 20 inside the other end. The command lever 18 uses the elastic body 52 to
The contact surfaces 50 are biased toward each other, and are thereby pressed by the pusher 20.

As shown in FIG. 2, each contact surface 50 has flat first and second surfaces 50a, 50b which are horizontally spaced apart and extend horizontally at different heights.
And a slanted third surface 50c following the first and second surfaces to connect the first and second surfaces.
Both contact surfaces 50 face each other and are formed in opposite directions. However, the contact surface 50 may be a cam surface having another shape.

The pusher 20 is disposed between the contact surfaces 50 and is swingably supported by a pivot 54 extending between the contact surfaces 50 and parallel to the shaft 28. The pusher 20 has a contact portion 56 that comes into contact with the contact surface 50 at each of both ends of the main body portion in the vertical direction.

In the illustrated example, each contact portion 56 has a contact surface 5
It is a projecting portion that projects toward 0, and the tip surface is a spherical surface or an arc surface. Instead of using the protruding portion as the contact portion 56, a spherical or roller-shaped member is used.
It may be arranged so as to be rotatable and non-removable in the main body 0. The contact surface 50 may be provided on the pusher 20 and the contact portion 56 may be provided on the command lever 18.

The selection lever 22 is attached to the pusher 20 and extends from the side portion of the pusher 20. An attraction piece 58 attracted to the magnet 24 is attached to the tip of the selection lever 22. The selection lever 22 is biased by the elastic body 60 in a direction in which the attraction piece 58 is separated from the magnet 24. The magnet 24 is an electromagnet and is attached to a support member 62 parallel to the shaft 28. Selection lever 22
The extending direction of the can be any direction such as upward and lateral.

In the illustrated example, the elastic bodies 42, 52,
Although a tension coil spring is used as 60, another elastic member such as a compression coil spring or rubber may be used. The shafts 28, 40 and the pivots 46, 54 are supported by the frame 64 (see FIG. 3) of the dobby. Shafts 28, 40, pivots 46, 54, and support member 6
2 is commonly used by all the actuating mechanisms 10 or a plurality of actuating mechanisms 10, but may be provided for each actuating mechanism 10.

When the selection lever 22 is displaced by the force of the elastic body 60 to the position where the attraction piece 58 is separated from the magnet 24, the abutting portion 56 of the pusher 20 has the abutment portion 56 of the first surface 50a of the command lever 18. Is displaced to a position where it comes into contact with. Therefore, the command lever 18 moves the elastic body 5 to the position where the push portion 48 pushes the knife hook 16.
Is displaced against the force of the elastic body 42 by the force of 2.
Further, the knife hook 16 is displaced to a position where it cannot engage with the connecting hook 16.

When the selection lever 22 is displaced against the force of the elastic body 60 at the position where the attraction piece 58 abuts the magnet 24, the abutment portion 56 of the pusher 20 is the second portion of the command lever 18. Is displaced to a position where it abuts the surface 50b of the. Therefore, the command lever 18 is displaced to the position where the push portion 48 is separated from the knife hook 16 against the force of the elastic body 52, and the knife hook 1
6 is displaced by the elastic body 42 to a position where it can be engaged with the connecting hook 14.

With the selection lever 22 displaced to a position where the attraction piece 58 is separated from the magnet 24,
When the rocking lever 38 is rocked, the knife hooks 16 are moved in the opposite directions, but the connecting hook 14, the vertical lever 12 and the jack lever 26 are not displaced.

On the other hand, when the swing lever 38 is swung while the selection lever 22 is displaced to the position where the attraction piece 58 contacts the magnet 24, the knife hook 16 moves to the leftmost position in FIG. When it is moved to one side, that is, when it is closest to the connecting hook 14, it engages with the connecting hook 14, and when it is moved to the right in FIG. 1 in that state, the connecting hook 14 is moved in the same direction. .
As a result, the vertical lever 12 and the jack lever 26 are swung so that the pivot shaft 30 is pulled rightward in FIG.

When one connecting hook 14 is pulled to the right in FIG. 1, the other connecting hook 14 abuts the stopper 34 unless the other connecting hook 14 is engaged with the corresponding knife hook 16. In this state, one of the connecting hooks 14 is pulled, so that the vertical lever 12 is pulled with the side of the other connecting hook 14 as a fulcrum so that the position of the pivot 30 thereof moves to the right in FIG. . As a result, the one or more heald frames connected to the jack lever 26 are raised.

On the other hand, one connecting hook 14 is shown in FIG.
When the other connecting hook 14 is pulled to the right in FIG. 1 when it is pulled to the right in FIG. 1, one connecting hook 14 is pulled to the right in FIG. It moves to the left in FIG. 1 together with the knife hook 16 engaged with it. That is, both connecting hooks 14 are moved in opposite directions. Therefore, the vertical lever 12 is swung around the pivot shaft 30 with the position of the pivot shaft 30 being hardly changed, and as a result, one or more heald frames connected to the jack lever 26 are maintained in the raised state. To be done.

If the contact surface 50 is a cam-like surface like the actuating mechanism 10, the relative movement of the command lever 18 and the pusher 20 accompanying the position displacement of the pusher 20 becomes smooth, and the position displacement of the pusher 20 becomes smooth. The impact caused by is reduced. As a result, the attraction piece 58 attracted to the magnet 24 is prevented from being separated from the magnet 24 due to the positional displacement of the pusher 20, thereby preventing the occurrence of a weaving error.

In the operating mechanism 10, the line connecting the contact portion between the command lever 18 and the pusher 20 and the center of the swing motion of the command lever 18 is the command lever 18 and the pusher 20.
It is at a right angle to the line connecting the contacting part with and the center of the swing motion of the pusher 20. As a result, the relative movement of the command lever 18 and the pusher 20 at the contact point between the command lever 18 and the pusher 20 becomes smoother, and the impact caused by the position displacement of the pusher 20 becomes smaller. The removal of the attraction piece 58 from the magnet 24 is reliably prevented, and the occurrence of weaving mistakes is reliably prevented. However, the above two lines do not have to be right angles.

The magnet 24 is energized while the heald frame corresponding to the actuating mechanism 10 should be raised (in the illustrated example, during one weft insertion period). When the attractive force of the magnet 24 is large, by energizing the magnet 24,
The attraction piece 58 can be attracted to the magnet 24, and the knife hook 16 can be displaced to a position where it can be engaged with the connecting hook 14.

However, since the dobby is generally provided with a plurality of actuating mechanisms 10, when a magnet having a large attracting force is used, the attracting piece of the actuating mechanism which does not need to raise the heald frame is the magnet of the adjacent actuating mechanism. The movement of the heddle frame cannot be controlled correctly as a result of the influence of the suction force.

To prevent this, the dobby also
It includes a first drive mechanism 66 that periodically moves the command lever 22 in synchronization with the rotation of the main shaft of the loom so that the attraction piece 58 approaches, preferably contacts the magnet 24.

As shown in FIG. 3, the first drive mechanism 66 includes a pair of side plates 68 that are immovably supported by the pivot 54.
And a rod 7 connecting the side plates to each other at their ends.
0 and a stop ring 72 that prevents the pivot 54 from disengaging from the frame 64. One side plate 68 is swung in synchronization with the rotation of the main shaft of the loom, and the pivot shaft 54 is rotatably received by the frame 64. Therefore, when one side plate 68 is swung, the other side plate 68 is also swung at the same time.

The first drive mechanism 66 is normally displaced to a position where the suction piece 58 is separated from the magnet 24 by the force of the elastic body 60. However, at the timing corresponding to the start of energization of the magnet 24, the attraction piece 58 is displaced for a certain period of time to a position where it makes contact with the magnet 24 against the force of the elastic body 60. While the suction piece 58 is in contact with the magnet 24, the magnet 24
When the magnet is energized, the attraction piece 58 is attracted to the magnet 24.

By using the first drive mechanism 66 as described above, even if a magnet having a small attracting force is used, the attracting piece 58 is reliably attracted to the magnet 24, and the attracting piece corresponding to the magnet that is not energized is energized. Moreover, the movement of the heddle frame can be accurately controlled without being affected by the attraction force of other magnets.

As described above, the contact portion 5 of the pusher 20
When 6 is constantly in contact with the cam-shaped contact surface 50 of the command lever 18, there is almost no impact when the pusher 20 moves with respect to the command lever 18, and therefore even if a magnet having a small attraction force is used, There is no risk that the suction piece that is attracted to the magnet will separate from the magnet.

In general, when a weaving error such as a weft insertion error occurs, the loom is temporarily stopped, a process for eliminating the weaving error such as removing the weft yarn is performed, and then the normal rotation is restarted. This weaving error processing is performed by removing the one or more weft yarns while reversing the weaving machine, because weft insertion is performed once or more from the time when the weaving error occurs until the loom stops. .

In order to deal with such a weaving error, the dobby further forces the attraction piece 58 to contact the magnet 24 for a certain period of time when the loom is rotated in the reverse direction and then when the loom is rotated in the normal direction. 2 drive mechanism 74
including. The second drive mechanism 74 is a cylinder mechanism attached to the frame of the dobby, and pushes the selection lever 22 toward the magnet 24 for a certain period of time when starting the reverse rotation of the loom and restarting the normal rotation. As the second drive mechanism 74, as a drive source, a drive mechanism using an electric motor, a solenoid mechanism, a manually operated drive mechanism, or the like may be used.

Next, the operation of the operating mechanism 10 will be described with reference to FIG.

In FIG. 4, reference numerals 180 and 360 indicate the rotation angles of the main shaft of the loom, the numbers in parentheses indicate the number of weft insertions, and the numbers 80 and 82 indicate the upper and lower knife hooks 16 in FIG. 1, respectively. 2 shows the positions of the upper knife hook and the lower knife hook in the left-right direction in FIG.

FIG. 4A shows the positions of the upper knife hook and the lower knife hook in the left-right direction in FIG. The uppermost position and the lowermost position in FIG.
The corresponding knife hooks respectively correspond to the position pulled to the right and the position returned to the left with the swing movement of the swing lever 38.

FIG. 4B shows a command signal for deciding whether or not to energize the magnet 24, which is a command signal for each weft insertion when the weaving machine is normally rotated.

FIG. 4C shows a command signal for determining whether or not to energize the magnet 24, which is a command signal for each weft insertion when the weaving machine is reversely rotated due to a weaving mistake or the like.

FIG. 4D shows a period (reverse rotation prohibition zone) in which the switching of the loom from normal rotation to reverse rotation is prohibited.

FIG. 4 (E) shows a period (forward rotation prohibited zone) in which the switching of the loom from reverse rotation to forward rotation is prohibited.

FIG. 4F shows the position of the attraction piece 58 with respect to the magnet 24. In FIG. 4F, a high level indicates a period during which the attraction piece 58 approaches or contacts the magnet 24 by the first drive mechanism 66, and a low level indicates a period during which the attraction piece 58 is separated from the magnet 24. Show.

FIG. 4G shows a reverse rotation prohibition zone of the conventional dobby.

FIG. 4H shows a forward rotation prohibition zone of a conventional dobby.

In FIGS. 4B and 4C, the reason why the number of weft insertions of the command signal is different between the forward rotation and the reverse rotation is that the magnet is actually energized and the actual weft insertion is performed. Because there is a time difference.

When the loom and the dobby are operating normally, the upper knife hook is moved to the left from time T1 to time T5, to the right from time T5 to time T9, and from time T9 to the next. Will be moved to the left until the predetermined time.
On the other hand, the lower knife hook is moved in the opposite direction to the upper knife hook. Further, the attraction piece 58 is brought into contact with or brought into contact with the magnet 24 by the first drive mechanism 66 from time T2 to time T4, from time T6 to time T8, and from time T10 to the next predetermined time. It

During forward rotation of the loom, the energization of the magnet 24 is controlled by using the command signal shown in FIG. 4 (B).

Therefore, for example, if the command signal for the seventh weft insertion shown in FIG. 4 (B) is an energization command to the magnet 24, the magnet 24 is between time T2 and T6.
When the magnet is energized, the attraction piece 58 is attracted to the magnet 24, and each of the upper knife hook and the lower knife hook is maintained at a position where it can be engaged with the connecting hook 14 between times T2 and T6. As a result, the connecting hook 14 corresponding to the upper knife hook is moved to the left if it is engaged with the upper knife hook, whereas the connecting hook 14 corresponding to the lower knife hook is moved to the right. Be moved.

However, if the command signal for the seventh weft insertion shown in FIG. 4 (B) is not the energization command to the magnet 24, the suction piece 58 causes the magnet 24 to move at the time T4.
When separated from each other, the upper and lower knife hooks are returned to the positions where they cannot be engaged with the corresponding connecting hooks. as a result,
The upper and lower knife hooks are moved along with the swing motion of the swing lever 38, but the connecting hooks are not moved.

When a weaving error occurs during normal rotation of the loom, the loom stops after one or more weft insertions have been performed. The loom is then reversed to handle the miss weave.

At the time of reverse rotation, the suction piece and the upper and lower knife hooks move in the opposite direction to those at the time of normal rotation. For example, if the start of reverse rotation is at time T9, the upper knife hook will start at time T9.
Moved to the left for the corresponding time between time T5 and time T5
~ Move to the right for the corresponding time between time T1. On the other hand, the lower knife hook is moved in the opposite direction to the upper knife hook. Further, the suction piece 58 has a time T8 to a time T6.
During the period of time, and the time corresponding to the period between time T4 and time T2, respectively, are brought close to or contact the magnet 24 by the first drive mechanism 66.

However, during reverse rotation, the energization of the magnet 24 is controlled using the command signal shown in FIG. Therefore, at the time T9 when the reverse rotation starts, as shown in FIG.
As shown in (F), the attraction piece 58 is attached to the magnet 24.
Even if the command signal for the sixth weft insertion is a signal for energizing the magnet, the upper and lower knife hooks are displaced to a position where they can be engaged with the connecting hook. Since it is not, the connecting hook cannot be pulled to the right.

As a result, the corresponding heddle frame is not moved upward and the weaving pattern for the sixth (sixth) weft insertion, that is, the opening pattern is not reproduced, so that it is difficult to remove the weft yarn of the sixth weft insertion. become. The above problem occurs not only when the reverse rotation is started but also when the normal rotation is restarted.

In order to solve the above problem, in the conventional dobby, as shown in FIGS. 4 (G) and 4 (H), it is necessary to provide a relatively large reverse rotation prohibition band and a normal rotation prohibition band.

On the other hand, according to the dobby equipped with the second drive mechanism 74, when the reverse rotation is started and the normal rotation is restarted,
Since the attraction piece 58 approaches or contacts the magnet 24, the attraction piece 58 is moved by the first drive mechanism 66 to the magnet 2 even when the reverse rotation is started and the forward rotation is restarted.
4 is reproduced even at the time when the weaving pattern is not approached or touched.

According to the dobby provided with the second drive mechanism 74, as shown in FIGS. 4C and 4D, the reverse rotation prohibition band and the normal rotation prohibition band are determined by mechanical processing error or the like. Can be set to the minimum value, which gives a large time margin for weft insertion.

The present invention is not limited to the double-action dobby in which the vertical lever 12 is swung by the pair of knife hooks 16 as in the above embodiment, but the vertical lever 1 is also used.
Dobby that swings 2 with one knife hook 16,
The present invention can also be applied to other types of dobby, such as a dobby that periodically moves the connecting hook 14 toward and away from the knife hook 16.

The dobby actuating mechanism 80 shown in FIG. 5 periodically moves the connecting hook 14 and the stopper 34 toward and away from the knife hook 16 as indicated by an arrow 81 in the figure. Both stoppers 34 are supported by a member 82 supported by the pivot 30. Each knife hook 1
6 is swingably supported by a pivot 46 that is immovable in the left-right direction in the figure, and the range of the pivot movement is limited by a stopper 84. Such a type of actuating mechanism is described in, for example, Japanese Patent Publication No. 2-23611.

Each command lever 18 of the operating mechanism 80 is fixed to the knife hook 16 by bolts or the like. Although the contact surfaces 50 are not indicated by reference numerals, each contact surface 50 has a flat first and second surface 5 as in the embodiment shown in FIG.
0a, 50c and an inclined third surface 50b following the first and second surfaces. In the case of the operating mechanism 80, each command lever 18 may be provided integrally with the knife hook 16, such as forming the contact surface 50 of each command lever 18 on the knife hook 16.

In the above embodiment, the vertical direction in FIG. 1 has been described as the vertical direction in the actual loom, but the present invention sets the horizontal direction in FIGS. 1 and 5 to be the vertical direction in the actual loom. You may use.

Further, the first and second drive mechanisms 66, 7
4 may be provided for each operating mechanism 10, and the first and second
The drive mechanisms 66 and 74 of 1 may be commonly used for all the actuating mechanisms or a plurality of actuating mechanisms.

Furthermore, the function of the second drive mechanism may be added to the function of the first drive mechanism. In this case, a drive source such as a cylinder mechanism is used as a drive source for the first drive mechanism, and the first drive mechanism is not only operated in synchronization with the rotation of the main shaft of the loom, but also at the start of reverse rotation and thereafter It should be operated when the normal rotation is restarted.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a dobby of the present invention.

FIG. 2 is an enlarged view showing the vicinity of a command lever in the dobby shown in FIG.

3 is an enlarged sectional view taken along line 3-3 in FIG.

FIG. 4 is a diagram showing a time chart for explaining the operation of the dobby shown in FIG.

FIG. 5 is a view showing another embodiment of the dobby of the present invention.

[Explanation of symbols]

10,80 actuation mechanism 12 Vertical lever (3rd lever) 14 Connection hook (first hook) 16 Knife hook (second hook) 18 Command lever (first lever) 20 pushers 22 Selection lever (second lever) 24 magnets 26 Jack Lever 34 Stopper 38 Swing lever 42,52,60 elastic body 58 Suction piece 66 First drive mechanism 74 Second drive mechanism

Claims (5)

(57) [Claims] 1. A first hook and a second hook which are relatively moved toward and away from each other, wherein the first hook is connected to a heald frame, and the second hook is the first hook. First and second hooks pivotable between a first position disengageable with the hook and a second position engageable with the first hook; and the second hook being the first A first lever that is selectively displaceable to a third position that controls displacement to the second position and a fourth position that controls displacement of the second hook to the second position; A fifth lever for controlling the displacement of the first lever to the third position
And a sixth position for controlling the displacement of the first lever to the fourth position, and a pusher capable of swinging motion, and the pusher selectively to the fifth and sixth positions. A second lever that is displaced, a magnet that releasably attracts the second lever to maintain the pusher at one of the fifth and sixth positions, and the second lever, in synchronism with the rotation of the loom main shaft and a drive means for moving toward the magnet at the reverse rotation start and forward rotation start of the loom main shaft is moved cyclically toward the magnet, said first
One of the lever and the pusher is the first lever.
-And the other part of the pusher comes in contact with the cam shape
Dobby with contact surface . 2. The first drive mechanism for moving the second lever periodically toward the magnet in synchronism with the rotation of the main shaft of the loom, and the drive means for moving the second lever to the loom. A second drive mechanism for moving the main shaft toward the magnet at the time of starting reverse rotation and restarting normal rotation.
The dobby according to claim 1. 3. A pair of the first hooks pivotally attached to a third lever capable of swinging movement and arranged at positions opposite to each other with respect to the swing center of the third lever, and the first hooks. A pair of second hooks that are individually associated with the first hook and that are engageable with the corresponding first hook, and a pair of second hooks that are individually associated with the second hook and that control the corresponding second hook. The dobby according to claim 1 or 2, further comprising: the first lever, wherein the pusher controls both of the first levers. 4. A first elastic body for exerting a force for displacing the second hook to the second position on the second hook, and both of the first levers at the third position. A second elastic body that exerts a force for displacing the first lever on the first lever, and a third elastic body that exerts a force for allowing the pusher to displace to the fifth position on the second lever. 4. The second hook according to claim 3 , wherein the second hook is maintained in the second position by the force of the first elastic body when the second lever is attracted to the magnet. Dobby. 5. An elastic body that exerts a force that displaces the second hook to the second position on the second hook, and a force that allows the pusher to displace to the fifth position. And another elastic body that acts on the second lever, wherein the first hook is configured such that when the second lever is attracted to the magnet, the force of the first elastic body causes the first hook to move the first hook. The dobby according to claim 3, maintained in the 2 position.