The present invention relates to a control mechanism, in particular suitable for, but not exclusively, a Jacquard mechanism of a weaving loom.

In weaving, it is highly desirable for a Jacquard to control displacement of individual healds. In electronically controlled jacquards it is common to connect several healds to a single harness cord which is then controlled for shed selection.

Desirably, each individual heald should be connected to a single harness cord but in order to achieve this goal, it is necessary to provide a control selector for each individual heald. This means that a large number of selectors have to be provided. Commonly in electrically controlled Jacquards, each selector is actuated by a respective selectively operable solenoid. Solenoids consume a large amount of electrical energy and generate heat.

Accordingly, it is highly undesirable to increase the number of solenoids used for controlling selection of healds. In addition, due to the inevitable bull y nature of solenoids and the available space for accommodating the solenoids, it is difficult to accommodate a sufficient number of solenoids for control of individual warp ends particularly above a loom having a high density warp sheet.

It is therefore a general aim of the present invention to provide a control mechanism which has the capability of selectively operating individual selectors in an array of selectors wherein the actuating means, such as a solenoid, for selectively actuating the selectors are less in

number than the number of selectors.

According to one aspect of the present invention there is provided a shed forming device characterised in that the number of individually controlled lifting means is more than the number of actuating means.

According to another aspect of the present invention there is provided a control mechanism including an array of selectors, each selector being switchable between first and second switched conditions, the selectors being arranged in a plurality of rows and a plurality of columns, the selectors in a column being interconnected by a column control element and the selectors in a row being interconnected by a row control element, each column control element being actuated by first actuation control means and each row control element being actuated by second actuation control means, each selector being arranged for co-operation with a respective column control element and a respective row control element so as to be switchable between its first and second switched conditions on actuation of said respective column and row control elements.

Preferably the selectors in each column are arranged to be simultaneously acted upon by the respective column control element so as to be changeable from a non-activated condition to an activated condition, the row control elements being arranged to be co-operable with selectors in said activated condition for switching those selectors between said first and second switched conditions.

Preferably each column control element is a rigid drive element which is either longitudinally and/or rotationally displaceable for moving selectors in a respective column between non-activated and activated

conditions.

Preferably each row control element is a rigid drive element which is either longitudinally and/or rotationally displaceable for switching activated selectors between first and second actuated conditions.

Preferably each selector is rotatably mounted in a support, said column control elements when actuated being moved from a rest position to an actuated position so as to rotate selectors in a respective column from a first rotary position, corresponding to said non-activated condition and said first switched condition, to a second rotary position corresponding to said activated condition.

The row control elements when actuated may be arranged so as to be movable from a rest position to an operable position so as to rotate activated selectors from said second rotary position to an intermediate further rot.ary position from which the selector is rotated to a rotary position corresponding to said second switched condition.

Alternatively, the selectors may be axially displaceable also and the row control elements may be arranged to axially move the activated selectors at said second rotary position from a first axial position to a second axial position corresponding to said second switched condition.

Preferably each column and row control element is acted on by a respective selectively operable actuating means which is electronically controlled. The actuating means may comprise a solenoid, a motor, or an electrostrictive drive strip.

Various aspects of the present invention are hereinafter described

with reference to the accompanying drawings, in which :

Figures la, lb are schematic diagrams of an array of selectors;

Figure 2 is a plan view of a control mechanism according to a first embodiment of the present invention;

Figure 3 is a more detailed plan view of a single selector shown in Figure 2;

Figure 4 is an axial sectional view through the selector shown in Figure 3; Figures 5 and 6 are plan views of a control mechanism according to a second embodiment of the present invention shown in different operating modes; and

Figure 7 is a side view of the mechanism shown in Figure 6.

Referring initi∑dly to Figures la and lb, there is shown an array of selectors 12. The selectors 12 are arranged in rows R and columns C.

As indicated in Figure lb, each selector 12 is capable of being switched between a first switched condition, indicated by 'N', and a second switched condition, indicated by O\

Each row of selectors 12 is acted upon by an actuating means 20 and each column of selectors 12 is acted upon by an actuating means 21. The actuating means 20,21 are used to switch individual selected selectors between their first and second switched conditions so that at the completion of the selection process, a predetermined array of switched selectors is produced.

Preferably at the initiation of a selection cycle, all selectors 12 reside at the same switched condition, in Figure lb this is the 'N'

condition. The actuating means 21 associated with the columns C are actuated in sequence in order to move the selectors 12 in a respective column from a non-active to an active condition.

Selected actuating means 20 are actuated after actuation of each successive actuating means 21 in order to cause selected activated selectors 12 to be moved to their second switched condition 'O' .

A selection sequence is schematically illustrated in Figure lb.

The actuating means 20,21 which have been actuated are shown in solid lines and those which have not been actuated are shown in broken lines.

The selectors 12 in column C ₅ have been set, those in column C ₄ actuated are in the process of being set and those in columns C, to C ₃ have been set. The actuating means 21 for column C ₄ has been actuated so as to move all selectors in column C ₄ to their activated condition. The remaining actuating means 21 are not actuated and so all selectors in columns C, to C ₃ and C ₅ reside at their non-activated condition.

Selected actuating means 20 are now actuated, these are in rows R,, R and R ₄ to cause activated selectors 12 in column C ₄ and in those rows to be switched to their second switched condition 'O'. The remaining selectors 12 in column C ₄ are not switched.

Although the actuating means for rows R,, R ₂ and R ₄ have been actuated, the selectors in these rows and columns C, to C ₃ and C ₅ are not affected since all these selectors are at their non-activated condition.

The actuating means 21 associated with column C ₄ is now de¬ activated such that selectors 12 in column C ₄ return to their non-activated condition.

The actuating means 21 of column C ₃ is now actuated and the sequence is repeated for setting of selectors 12 in columns C ₃ , C ₂ and C,.

Preferably individual actuating means 20, 21 are provided for each row R and column C. In this case, the number of actuating means 20, 21 required equals the sum of the number of columns and rows, i.e. for an array of 10 columns by 10 rows, twenty actuating means are required for individually operating one hundred selectors.

It will be appreciated that in a conventional electronic Jacquard operating on one hundred individual healds one hundred actuating means, eg solenoids, would be required and that the present invention substantially reduces the number of actuating means required.

It is envisaged that the individual actuating means 21 for actuating columns in sequence may be replaced by a single actuating means which sequentially operates on each column C.

In Figures la, lb the selectors 12 are arranged in a rectangular array having vertical columns and horizontal rows. It will be appreciated that other shapes of array comprising columns and rows may be adopted in order to perform the present invention, e.g. the selectors may be arranged in a triangular array, or a circular array in which the columns extend radially and the rows extend circumferentially.

A first embodiment 30 according to the prevent invention is

illustrated in Figures 2 to 4;

In Figure 2, an array of nine selectors 12 is shown comprising three rows and three columns.

Each selector 12 comprises a body 31 which is rotatably received in a support 25 (Figure 4). Each body 31 includes a drive pin 32 and a driving formation 33. In the embodiment illustrated, the driving formation 33 is an axial bore 26, but it is envisaged that other formations such as a projection may be adopted. The rotary orientation of each selector 12 is represented by arrow A.

The selectors 12 in each column C,, C ₂ , C ₃ are acted upon by respective column control elements 36 and the selectors 12 in each row R,, R ₂ , R ₃ are acted upon by respective row control elements 37.

Selectors in column C, have been set, selectors in column C ₂ are in the process of being set and selectors in column C ₃ have not yet been set.

Column elements 36 include a pair of recesses 40,41 for co¬ operation with each selector 12 and row elements 37 include a single recess 42 for co-operation with each selector.

Selectors 12 at R,, C, and R ₃ , C, are shown at their first switched condition S, (which corresponds to a first rotary position P,), and selector at R ₂ , C, is shown at its second switched condition S^, (which corresponds to a fourth rotary position P ₄ ).

All selectors 12 in column C ₃ are shown at their first switched position. All selectors 12 are biased for rotation in an anti-clockwise

direction, the selector bodies engaging against a stop (not shown) when at their first switched condition.

Column control element 36 for column C ₂ has been moved downwardly, from its rest position to its actuated position, and in so doing causes wall 40a of each recess 40 to engage a respective pin 32 and rotate the associated selector body 31 to a second rotary position P ₂ with corresponds to the activated condition of the selector.

Selectors at R,, C ₂ and at R ₃ , C ₂ are shown at their activated position whereby the pin 32 has been moved into the recess 42 of each row control element 37: however row control elements 37 for rows R _[ and R ₃ are at their non-actuated, rest, position and so the selectors reside at the second rotary position P ₂ .

Row control element 37 for row R ₂ has been actuated and has been moved from its rest position to a leftmost operational position as seen in Figure 2.

In moving to its leftmost position, the wall 42a of recess 42 engages the pin 32 and rotates selector body 31 to an intermediary third rotary position P ₃ whereat pin 32 is clear of recess 40.

Row control element 36 is now actuated to return to its upper rest position and in so moving selector bodies at R,, C ₂ and R ₃ , C ₂ return under the bias to the first rotary position P,. During upward movement of the column control element 37 for column C ₂ drive pin 32 of the selector at R ₂ , C ₂ remains in contact with the wall 42a of recess 42 and so remains at position P ₃

Row control element 37 for row R ₂ is now returned to its rightmost, rest, position and as it returns, pin 32 of the selector body 31 enters into recess 41 of column control element 36 for column C _: and, due to the bias, abuts against wall 41 a of recess 41. At this position, the selector body 31 resides at the fourth position P ₄ which corresponds to the second switched condition S ₂ .

All selectors 12 are set in sequence by actuating successive columns of selectors (i.e. successively moving the respective column control element 36 to its lower position) and then actuating selected row control elements 37.

Once the array of selectors has been set into a predefined pattern an operational process is performed, for example, when used in a Jacquard mechanism a particular shed is defined. After completion of the operational process, the array of selectors needs to be set into a new predefined pattern for the next operation.

As seen more clearly in Figure 3, the wall 41a is preferably rounded at 41b in order to enable the drive pin 32 to exit recess 41 as the column control element 36 is moved downwardly.

Accordingly, pin 32 rides on side edge portion 36a of element 36 as it continues its downward motion until pin 32 enters recess 40 and engages wall 40a. Thus continued downward movement of the column control element 36 moves the selector body 31 to its active position P ₂ . Thus on completion of movement of control element 36 to its downmost position, .all selector bodies 12 in column C ₂ reside at their P ₂ position irrespective of whether they resided at their S, or So condition at the start of movement of the column control element 36. Thus a new predefined

pattern of selectors can be immediately created at the termination of the operational process by repeating the sequence of sequentially actuating column control elements 36 and selectively actuating row control elements 37.

The column control elements 36 and row control elements are preferably biased in one longitudinal direction (preferably to reside at their rest position) and are each acted upon by electronically, controlled actuating means 46 such as a solenoid in order to move the respective element 36 or 37 to its actuated position.

In figure 4, an example of utilising the array of selectors 12 is illustrated in which each selector 12 controls axial displacement of a Jacquard actuating pin 150.

The pin 150 includes in its central region an enlarged square sectioned portion 151 and a circular guide portion 152.

The pin 150 is guided at one end in a support plate 153 and at its opposite end in a pusher plate 154 which is arranged to oscillate between a rest position (as illustrated in solid lines) and an actuating position (as illustrated in broken lines).

A spring 157 is provided for biasing the pin 150 toward the pusher plate 154 such that when the pusher plate 154 resides at its rest position, the pin 150 is located at a rightmost left position (as illustrated in solid lines) such that circular guide portion 152 is located within the bore 26 and square sectioned portion 152 is spaced from bore 26. The square sectioned portion 151 is also guided through a square sectioned through bore in a support plate 160. Accordingly, pin 150 is restrained from

rotation about its axis.

Once the array of selectors 12 has been set, some of the selectors 12 will be at their first rotary position P, (first switched condition) and some will be at their fourth rotary position P ₄ (second switched condition). One of these switched positions is chosen to .align the bore 26 with the square section portion 151 to thereby enable the portion 151 to enter bore 26 and enable the pin 150 to move axially in a leftwards direction to its actuated position (as illustrated in broken lines in Figure 4) as pusher plate 154 moves to its actuating position. At the other switched position of the selector 12, the bore 26 is not aligned with square sectioned portion 151 and so movement of the pin 150 in a leftward direction is blocked. A spring 172 is located between the pusher plate 154 and square sectioned portion 151 for transmitting drive from the pusher plate 154 to pin 150. If the pin 150 is blocked, the spring 172 is compressed as the pusher plate 154 advances to its actuating position.

It will be appreciated that the mechanism shown in Figure 4 could be adapted for retro-fitting to a Jacquard mechanism to replace the conventional card reader. Alternatively, the mechanism shown in Figure 4 could be adapted such that the pins 150 actuate retention latches for releasably engaging heald lifting rods or hooks in conventional Jacquard mechanisms.

A second embodiment 50 is illustrate in Figure 5.

In Figure 5, twelve selectors twelve are shown arranged in four columns C, to C ₄ and three rows, R, to R ₃ .

Such selector 12 comprises a rotary body 51 which is rotatably and

axially movably mounted in a support (not shown).

All selectors 12 shown in Figure 5 reside at their first switched condition S, corresponding to a first rotary position P, .

The column control elements 36 are in the form of toothed racks, the selector bodies 51 including pinion gear teeth 54 co-operating with rack gear teeth 56 on elements 36. The control elements 36 are each provided with an actuating means preferably in the form of a solenoid 58 which acts to move the respective element 36 from its lowermost inactive, rest position to an uppermost actuated position.

Each selector body 51 includes a worm gear 60 which has a first portion 61 extending part circumferentially about body 51 and a second portion 62 extending circumferentially about body 51 for a greater distance than portion 61. Portion 62 is located at a lower position on body 51 than portion 61 (see Figure 7)

Row control elements 37 are in the form of rotary drive shafts, each carrying pinion gears 66 for driving co-operation with the worm gear 60 on a respective actuating body 51.

Each control element 37 is provided with a drive motor 69 which is operable to rotate its respective drive shaft through a predetermined angular displacement.

In use, the column control elements 36 are actuated in sequence as in the previous embodiment.

As seen in Figure 6, column control element 37 for column C, has

been actuated and has moved to its actuated position. Accordingly, all selector bodies 51 in column C, have been rotated from a first rotary position, P,, to a second rotary position P ₂ .

In position P-,, pinion gears 66 are out of mesh with worm gear 60; in position P ₂ pinion gears are in mesh with worm gear 60.

Accordingly, after actuation of a column control element 37, selected row control elements 36 are rotated to cause selector bodies 51 located at position P ₂ to be moved axially from a first axial position A (Figure 7) to a second axial position A ₂ .

Actuated column control element 36 for column C _t is now returned to its lowermost rest position. During such movement, the selector bodies 51 are rotated in an anti-clockwise direction to return to position P,.

The worm gear portion 61 remjdns engaged with respective pinion 66 during initial rotary movement of each body 51 from position P, to P _! and so bodies 51 at the second axial position A ₂ remain at that position.

Located adjacent to each selector body 51 in a column is a retention means preferably in the form of a pinion gear 70 for co-operation with worm portion 62 only. The pinion gears 70 for a given column are mounted on a common shaft 71 which is normally retained in a static condition by a brake 72.

The length of worm portion 62 is such that as a body 51 at axial position A ₂ is rotated from position P ₂ to P,, worm portion 62 meshes with a respective pinion gear 70 before worm portion 61 disengages from pinion 66. Accordingly, when body 51 resides at position P,, it remains

at axial position A ₂ by virtue of meshing engagement between pinion 70 and worm gear portion 62.

The above setting sequence is repeated for each column until all selectors in the array have been set to switched condition S, or S^

An operational process is then performed. In the cost of utilising the control mechanism 50 in an electronic jacquard, the axial displacement of each selector body 51 between axial positions A,, A ₂ may be used to move heald hooks from one axial position to another or may be used to displace latch retention means for selectively holding heald hooks at a desired axial position.

For example, as shown in Figure 7, each selector body 51 may be provided with a through bore 52 through which a heald hook 1 1 1 may pass. The heald hook 11 1 is provided with a stop 112 which abuts against the top face 51a of the selector body 51. The heald rod 111 is biased downwardly such that stop 112 is biased into contact with face 51a. Accordingly axial displacement of body 51 between positions A,,A ₂ will cause a similar axial displacement in the heald hook 1 1 1.

After the operational process has been performed, all selector bodies 51 may be returned to their first axial position A, by release of brakes 72.

It will be appreciated that the number of selectors in an array according to the present invention can be chosen to meet the requirements of the operational mechanisms being controlled. For example, when used in jacquard mechanisms, it is envisaged that the array will contain about sixteen rows and sixteen columns and that more than one array may be

used, these arrays being arranged side by side.

It is to be appreciated that, in accordance with the present invention, each selector is arranged to control one or more lifting means in a shedding mechanism; for example the lifting means may comprise a heald rod or hook.

For each selector one or more input control elements are utilised to set the selector. The control elements .are preferably mechanical in nature and may be arranged to rotate and/or move longitudinally. Such movement may be caused by electromechanical or pneumatic or hydraulic means or by cyclical mechanical means such as cams.

It will be appreciated that several control elements may be operable on a selector in order to cause the selector to be set.

A further embodiment of the system is shown in Figures 8, 9 and 10, which illustrate the sequence of events in the mechanism. The grid system has a set of column drive rods 50 and row drive rods 51 , which intersect at the output points, and an additional set of output drive rods 53, equal in number to the number of column drive rods in the array. The system is shown in plan view, and operates on a vertical member 52 which is perpendicular to the grid as shown, and includes parts of its geometry along its length (not shown) which are capable of interacting with the other parts of the jacquard to produce selection of an end when required. The component 52 may be a catch mechanism. The rest position of the catch 52 is shown in Figure 8 as being in the slot in the column drive rod.

The rod 50 moves rightwards when actuated, the movement being

sufficient to bring the catch into a position whereby it may be engaged in the row drive rod, which it would otherwise be clear of. The column drive moves right and comes to rest, at which point the row drive may be actuated, by being moved upwards in the view shown, this movement being approximately perpendicular to the prior movement of the column drive and in the same plane. It is intended that the selection process depends only on the choice of actuation or otherwise of the row actuator, but it can be arranged that actuation does or does not produce selection in the jacquard. If actuated, the row drive 51 moves the vertical member 52 upwards so that the vertical member is disengaged from the column drive, and the row drive comes to rest in that position whilst the column drive retracts leftwards to its original position. This leaves the vertical member in the new position. In the embodiment shown, the row drive is also retracted at this point, the vertical member coming to rest on the column drive as shown if it were sprung in that direction. This condition is shown in Figure 9, in which both the column drive 50 and the row drive 51 are inactive. The vertical member 52 is engaged in a slot in the output drive member 53. The purpose of the extra drive 53 is to incorporate the function of preselection into the selection grid, since the interaction of the grid with the other parts of the machine can be designed such that there is no interaction whilst the vertical member is in the position shown in Figure 9. During the last part of the machine cycle, when all the outputs on the grid have been addressed and thereby set or not set, the output drive 53 is moved to the right, shifting the vertical member 52 to the position shown in Figure 10, the intention being that in this location the vertical member will interact with the rest of the machine, by means of other geometry incorporated into it, but which is not necessarily part of this preselection mechanism.

After the output phase the drive rod 53 is retracted to its original

position, so that the vertical member is as shown in Figure 9. If there is spring loading in the vertical member 52, such that it would oppose the movement imposed by the row selector, then it is not necessary to reset the grid before starting a new cycle of selecting the outputs on the grid. If an output has been selected on the previous cycle, the vertical member can spring back into the slot in the column drive rod when that rod is actuated, resulting in exactly the same condition as would occur if the output had been reset before commencing the next cycle. If the row drive is not actuated after the column drive has been moved, the vertical member will remain in the slot in the column drive and move leftwards when the column drive retracts, so that subsequent possible movements of that same row drive in the same major cycle, will not effect that output.

It should be noted that for the above system both the column drives and the output drives are always actuated in every cycle, regardless of selection of outputs or otherwise, and as such, they do not need to be moved by a switchable actuator. Instead, they could more conveniently be operated by an automatic mechanical means, such as cams, which simplifies the mechanism and ensures correct phase and speed of operation.