US3225792A

US3225792A - Dobby, specially adapted for speedy looms

Info

Publication number: US3225792A
Application number: US300302A
Authority: US
Inventors: Piazzolla Giovanni; Villa Carlo
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-12-15
Filing date: 1963-08-06
Publication date: 1965-12-28
Anticipated expiration: 1982-12-28
Also published as: GB1032014A; CH402759A

Description

Dec. 28, 1965 PIAZZOLLA E L SPECIALLY ADAPTED FOR SPEEDY LOOMS DOBBY,

4 Sheets-Sheet 1 Filed Aug. 6, 1963 Dec. 28, 1965 PIAZZOLLA ET AL 3,225,792

DOBBY, SPECIALLY ADAPTED FOR SPEEDY LOOMS Filed Aug. 6, 1963 4 Sheets-Sheet 2 Dec. 28, 1965 G. PIAZZOLLA ET AL 3,225,792

DOBBY, SPECIALLY ADAPTED FOR SPEEDY LOOMS 4 Sheets-Sheet 5 Filed Aug. 6, 1963 INVENTORS Dec. 28, 1965 G. PIAZZOLLA ET AL 3,225,792

DOBBY, SPECIALLY ADAPTED FOR SPEEDY LOOMS Filed Aug. 6, 1963 4 Sheets-Sheet 4 United States Patent O 3,225,792 BOBBY, SPECIALLY ADAPTED FOR SPEEDY LOOMS Giovanni Piazzolla, Via Salieri 6, Milan Italy, and Carlo Villa, Via Giuseppe Mazzini 24, Melzo, Milan, litaly Filed Aug. 6, 1963, Ser. No. 300,302 Claims priority, application Italy, Dec. 15, 1962, 24,672/ 62 12 Claims. (Cl. 13971) This invention relates to a dobby capable of reaching high working speeds, and therefore to be used on speedy looms.

The problem of rendering speedy dobbies in general had till now no particular consideration in the technique of weaving, because they were mostly used in conventional looms which are since the origin ratther slow in working. When but these devices were set up into speedy looms, they were to constitute a serious obstacle because of their low working, such as to require a heavy limiting of the working speed of said looms. The limited speed of said dobbies was mainly to be ascribed to the concept by which their mechanical parts were designed and built, so as to provoke high accelerations of moving of the heddles, and further high friction between the lever means themselves. As a matter of fact the movement of the sliding levers for the dogs was obtained by means of operating cams upon two angles of about 90 intersected by two resting angles, so as to compose an operating cycle comprising a step of hoisting of the heddles, a resting step, then a step of lowering the heddles, and a resting step in lowered position. The succession of these several steps of working and resting took place by means of very quick movements of said heddles, what matter gave accelerations, and therefore to considerable inertia of the same, so that an increase of speed was practically impossible, inasmuch as said heddles were induced to skip instead of to displace smoothly but quickly.

Further drawbacks hindering the quick movement of the dobbies were to be seen in the mode of lowering of the selected hooks, inasmuch as they lowered by the force of gravity, for which it was impossible to increase the speed of movement. Still a further drawback was given by the transmission of the movement of the hooks from the selecting knives, inasmuch as this operation took place by means of small bars in sliding contact each with other, such that an increase of speed should have caused a quick wearing of the hooks themselves. Another drawback was to be ascribed to the engaging system of said hooks onto the dogs, due to the fact that said hooks were built with an acute corner, which had to engage onto a corresponding acute edge of said dogs, for which the lasts, in order to be able to provide for said engagement were constrained to make a greater stroke in order to overgo the biased portion of said hooks.

The dobby according to this invention eliminates all said drawbacks.

A first object of said dobby is represented by the fact that the mechanisms for moving the dogs are provided with continuous movements without any resting intervals, such that the usually as resting steps used phases are utilised for imparting to the dogs a more smooth movement with a more smooth acceleration for which their drawing action onto said hooks, and consequently onto the heddles, will take place with a lesser acceleration, and a considerable reduction of the force of inertia, so that the frequency of the movements of the dogs will be considerably increased.

A further object of this invention is given by the fact that the pattern with fingers or in the form of perforated band is provided with an uninterrupted movement which is synchronised with the displacement of the dogs so as to act upon the selecting knives in anticipated periods of time, thus providing the selected hooks to quickly lower and engage the dogs, without any resting intervals for the lasts.

Still another object of the invention is to be found in the fact that in order to increase the quick lowering of the hooks onto the dogs the selecting knives are controlled in such a way that the hooks are released and then lowered an instant before the respective dog will reach its dead point of engagement, so that the hook, before engagement, will rest upon the dog by sliding thereon and consequently will further engage the acting edge as soon as the same will be reached.

A further object of the invention is given by the fact that the book ends, as well as the bar ends, which have to act upon said hooks, are provided with wear protecting means for the material subjected to friction, f.i. in the form of rollers, smooth surfaces, or the like.

Still a further object of the invention is that the hooks are returned downwards into the position of engagement by appropriate springs for a substantial acceleration of their speed under the action of gravity toward the dogs.

Still anotherobject of the invention has to be seen in the fact that the selecting knives are returned to a resting position by appropriate springs which also aid the disengaging movement of said hooks.

Another object of the invention consists of the fact that the dogs are fitted on the extension in the oscillating side of a respective articulated parallelogram which is brought to oscillation between two symmetrical positions in respect of the rectangular position of said quadrilateral so as to substantially reduce the curvature of the trajectory of said dogs.

Another object of the invention is ascribed to the fact that the engaging edge of the dogs and the hook corner of the hook levers are sustained in order to facilitate the engagement and in the same time to reduce the dog stroke.

A last object of the invention is the fact that along the trajector of the dogs protecting roofs are provided, under which the hook levers move, and the purpose of which roofs is to prevent that the said hooks spontaneously disengage from the dogs.

The aforesaid and further objects of this invention are represented as an example of its embodiment in the attached drawings, of which:

FIGURE 1 is a dobby for controlling the dogs and the pattern shaft;

FIGURE 2 is a section of the center of the dobby with the controlling leverage of the hooks and the levers for the movement of the heddles; and

FIGURES 3 to 9 show diagrammatically several working steps of the dobby of FIGURES 1 and 2.

Going back to FIGURE 1, from side wall 1 a drive shaft 2 projects, said shaft being driven with a continuous rotating motion. Said shaft bears keyed thereon two

cams

3 and 4, each an eccentric circular disk, conveniently phase displaced to cause displacements of the phase displaced dogs to 180. The axes of the circular or annular peripheral faces of

cams

3 and 4 are parallel to and equidistant from the axis of drive shaft 2. On each one of these cams

respective rollers

6 and 7 are positioned. Roller 6 is disposed at the end of arm 8 forming with the arm 9 an integral lever body. Said lever arm 9 combines with a parallel lever 10, and forms together with it and an upper rod 11, an articulated parallelogram engaged with pivots 12 and 13, so that, owing to the rotation of cam 3, said parallelogram oscillates in respect of the central rectangular position, and consequently rod 11 is submitted to alternate translations of small amplitude. At the extended end of said rod 11 there is a dog 14,

which as shown, has a rectangular cross section with a right angle engaging edge 15.

In a same manner roller 7 is supported by an arm 8' connected to a lever arm 9 which, together with a parallel lever 10 and a transversal lever 11, forms an oscill'ating articulated quadrilateral oscillating on respective pivots 12' and 13'. At the free end of rod 11 there is applied a second dog 14 with an engaging edge 15' of right angle. Also in this case the action of cam 4 on roller 7 causes an oscillation of the lever arms 9 and 10, and therefore a translating movement of small amplitude of the rod 11'.

The phase displacement of

cams

3 and 4 also causes the phase displacement of 180 of the dogs Hand 14', such that, when the one is wholly advanced, the other is wholly retracted, and vice versa.

As it may be seen on FIGURE 1 the reciprocating movement of the dogs 14 and 14', in opposite strokes is continuous; that is to say, without resting steps caused by the cams.

The rotary continuous movement of a small shaft 16, whereon an endless screw 17, meshing with gear 18 is keyed on the pattern moving shaft 19 so that said pattern will be advanced by a continuous, and not any more intermittent movement as with the conventional dobbies, is transmitted onto shaft 2 by means of a transmitting device and an appropriate speed reduction transmission (not shown).

Behind'plate 1 a row of hooks is located, as shown in FIGURE 2, wherein only a pair of them is represented in action upon a unique heddle.

Referring now to said FIGURE 2, draw hooks 20, 2t), respectively of the upper row of hooks, and of the lower one, have a rectangularly made hook edge in order to en sure a quick engagement onto dogs 14, 14'. The draw hooks are located on rectilinear rods or arms 21, 21', respectively, biased downwards by

respective springs

22, 22. Rods 21, 21' are articulated at the ends of a lever 23, known as a baulk lever and displaced by that hook which is brought to advance by the respective dog articulated at the opposed end, said articulation taking place on two

resting points

24 and 25, alternately. In an intermediate position, said lever 23 supports a pivot 26 to which a specially shaped lever 27, articulated at one end on a pivot 28, and having at the opposed free end a hook 29 connected through a link with a connecting rod 30 acting upon a heddle in the known manner.

Said lever 27 therefore is displaced by the lever 23 following both the movements of the

hooks

20 and 20, respectively and alternately,

The shaft 19, brought into continuous rotation by the gear 18 (FIGURE 1), carries a pattern drum 31 mounted with the purpose of moving in continuation a manufacturing pattern operating by means of operating fingers. Said drum 31, or another equivalent pattern control device, may also drive in continuation a pattern in the form of a perforated paper band of a type known in the art.

In the actual case, the pattern drum 32 is provided with operating fingers 33 and it acts upon a series of pairs of knives or

follower members

34 and 35, known per se, and pivoted on a common shaft 36, being provided at their lower portion of specially shaped cam profiles with which the fingers 33'of the pattern 32 cooperate.

Knives 34 and 35 are urged backwards by

springs

37, 38, respectively, and at the front part the knife 34 acts upon a vertical hook needle rod 39, whilst the other knife 35 acts upon a shorter also vertical hook needle rod 40. Said vertical rod 39 has at its upper end a roller 41 which acts upon the arm 21 of the hook 20. In the same manner the shorter rod is provided with a roller 42 by means of which the arm 21' of the hook 29' is actuated.

Members

34, 35 constitute motion transmitting means between pattern control means 32, 33 and the draw hooks.

The ends of

hooks

20 and 20 are provided with respective rollers 43 and 44 (FIGURE 1). These rollers serve to reduce friction of the contacting parts in movement such that notwithstanding the high speed of operating no wear of these last mentioned parts will occur.

The disposition of the cam profiles of

knives

34 and 35, and further even of the moving and continuous forwarding of fingers 33 are exactly synchronised by the rotation of the eccentrically set

cam wheels

3 and 4 of FIGURE 1 so that the hooks are operated by the pattern 32 with the required selection in manufacturing while the dogs, which are moved by said eccentric wheels, are submitted to their continuous alternating movement, without any resting interval, in order to ensure their selection or disengagement in preceding times in respect of that of the rear dead point of the dogs as it will be explained later. In front of the hooks 2t), 20, guiding

strips

45 and 46, respectively, are provided at the underside of which the dogs travel, when moved forwardly, with the view to prevent disengagement of said hooks.

FIGURES 3 through 9 refer to successive steps of operation of the dobby of FIGURES 1 and 2, in operating with a double raising stroke.

In FIGURE 3 it is supposed that hook 20' has just been disengaged, while hook 20 is raised, so that dog 14 has reached its rear dead point, and dog 14 is still in its front dead point. In this position, knife 34 is not engaged by the finger 33, whilst knife 35 is still engaged by the finger 33' which has lowered the small rod 40, thus permitting hook 20 to fall onto the dog 14'. As cams 3 and 4 (FIGURE 4) continue to rotate, the dog 14' also continues to advance, thus trailing the hook 20 so that it enters a position underneath the guiding strip 46, while dog 14 freely relapses. Rod 23 oscillates, being fulcrated on the supporting means 24, thus also trailing in this movement the specially shaped lever 27, as represented in FIGURE 2. Finger 33 almost contacts with the profiled knife portion 34, while finger 33 still engages the profiled knife portion 35.

In the successive working step of FIGURE 5, due to the further forwarding of dog 14 and withdrawing of dog 14, the finger 33 has advanced so as to engage the profiled track of knife 34, thus causing lowering of the longer rod 39. Thus hook 23 instantly falls under the drawing action of spring 22, as shown in FIGURE 2. At the same time dog 14 has been displaced to a position in which said hook rests and through roller 43 also travels thereon, thus assuming the position of selection, while dog 14' continues to advance.

In the working step of FIGURE 6, and continuing the rotation of the

eccentric wheels

3 and 4, the dog 14' has reached its dead center on the right, thus controlling the largest displacement of the hook 20' and the maximum oscillation of the lever 23'pivoted on support 24.

At the same time, the dog 14- has moved to its rear dead center position, and-the hook 20, due to the action of spring 22, has lowered, thus'engaging the dog 14. Simultaneously, the fingers 33 and 33' have further advanced and contacted with the respective profiled tracks of

knives

34 and 35.

In the working step of FIGURE 7, wherein the eccentric wheels 3'and 4 still rotate, the forward movement of dog 14 begins, thus trailing the hook 20, which engages underneath the guiding strip 45, thus also controlling the displacement of lever 23 to the corresponding direction, so as to disengage from its support 24. In the same time the dog 14' begins its return stroke, thus tending to bring the lever 23 to rest on the support 25. Simultaneously the fingers 33 and 33' are both still contacting with the respective profiled tracks of

knives

34 and 35.

In the working step of FIGURE 8, the forward movement ofthe clog 14'and consequently the advancing of the hook 24) has continued with the consequent moving away of lever 23 from its support 24, while the dog 14' continues to run backwards, so that the hook 20 will be brought almost out of the guiding strip 46, thus causing the lever 23 to approach still more the lower support 25. In this position, finger 33 is still in contact with the profiled track of the knife 34, whilst the finger 33' is to abandon the profiled track of knife 35.

In the working step of FIGURE 9, the dog 14 has wholly advanced underneath the guiding strip 45 and has thus caused the greatest displacement of the hook 20, thus obtaining maximum distance of the lever 23 from the support 24. In the same time the dog 14 has completed its return stroke, and caused the maximum return of the hook 20', thus bringing the lever 23 to rest on the support 25. In this position the finger 33' has left the profiled track of knife 35, whilst the finger 33 is still in contact with the profiled portion of knife 34. Consequently, in this position the knife 35, due to the action of the spring 38, can raise its free end, by raising the smaller rod 40 and together with it the hook 20, disengage it.

Considering again the FIGURES 3 through 9, it appears evident that the uninterrupted and synchronised action of the several members, due to the total absence of resting intervals of the dogs, and further on account of the according control ofthe lever 23, which is moved for the double stroke of raising, its control pivot 26 is always held outside of the usual line of resting, so as to always maintain the heddle engaged thereby correspondingly raised in order to ensure the double raising stroke thereof.

Of course, continuing the rotation of the

wheels

3 and 4, a further selection step may take place, in accordance with the formation of the pattern strip 32 with an according development which will reflect that of the preceding working steps.

It is evident from the FIGURES 3 through 9 that the trajectory of the dogs 14 and 14' constitutes a little accentuated curvature thus facilitating a quicker operation of the dobby, a better performed action of the guiding strips 45 and 46 in preventing the spontaneous disengaging of the hooks, whilst the provision of supporting means for said dogs in the form of articulated quadrilaterals allows a much higher frequency of the reciprocating strokes of said dogs.

Of course this invention is not limited to the embodiment shown herein by way of a sole example of execution of its subject matter, and modifications and variants are possible for people skilled in the art without going beyond the limitations stated in the following claims.

What we claim is:

1. A dobby comprising, in combination, a pair of dog means mounted for reciprocating movement along two paths; drive means for reciprocating said dog means in opposite reciprocating forward and rearward strokes; baulk lever means mounted for oscillatory movement; a pair of draw hook means mounted on said baulk lever means for angular movement between first positions located in said paths of said dog means, respectively, and second positions spaced from said paths; and rotary pattern means including periodically moving control means and motion transmitting means actuated by said periodically movable control means of said rotary pattern means and cooperating with said draw hook means for placing each draw hook means in said first position thereof during the forward stroke and also during the last part of the rearward stroke of the correlated dog means whereby the respective hook means is reciprocated by the correlated dog means and is already in said second position thereof when the correlated dog means starts the forward stroke thereof.

2. A dobby comprising, in combination, a pair of dog means; drive means for reciprocating said dog means in opposite forward and rearward strokes and including a drive shaft having an axis, a pair of drive members eccentrically mounted on said drive shaft and having annular faces having axes parallel to the axis of said drive shaft equidistant from said axis, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said annular faces of said drive members, respectively, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means mounted on said baulk lever means for angular movement between first positions located in said paths of said dog means, respectively, and second positions spaced from said paths; and rotary pattern means including periodically moving control means and motion transmitting means actuated by said periodically movable control means of said rotary pattern means and cooperating with said draw hook means for placing each draw hook means in said first position thereof during the forward stroke and also during the last part of the rearward stroke of the correlated dog means whereby the respective hook means is reciprocated by the correlated dog means and is already in said second position thereof when the correlated dog means starts the forward stroke thereof.

3. A dobby comprising, in combination, a pair of dog means; drive means for reciprocating said dog means in opposite reciprocating forward and rearward strokes and including a drive shaft having an axis, a pair of drive members eccentrically mounted on said drive shaft and having annular faces having axes parallel to the axis of said drive shaft equidistant from said axis, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said annular faces of said drive members, respectively, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means mounted on said baulk lever means for angular movement between first positions located in said paths of said dog means, respectively, and second positions spaced from said paths; rotary pattern means having two sets of control projections; and a pair of follower members connected with said draw hook means, respectively, for moving the same between said first and second positions, said follower members cooperating, respectively, with said sets of control projections whereby said hook means are reciprocated by said dog means.

4-. A dobby comprising, in combination, a pair of dog means; drive means for reciprocating said dog means in opposite forward and rearward strokes and including cam means, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said cam means, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means mounted on said baulk lever means for angular movement betwen first positions located in said paths of said dog means, respectively, and second positions spaced from said paths; and rotary pattern means including periodically moving control means and motion transmitting means actuated by said periodically moveable control means of said rotary pattern means and cooperating with said draw hook means for placing each draw hook means in said first position thereof during the forward stroke and also during the last part of the rearward stroke of the correlated dog means whereby the respective hook means is reciprocated by the correlated dog means and is already in said second position thereof when the correlated dog means starts the forward stroke thereof.

5. A dobby comprising, in combination, a pair of dog means; drive means for reciprocating said dog means in opposite forward and rearward strokes and including cam means, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said cam means, each of said parallelogram linkages being connected to one of the dog means so that the same are reciporcated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means, each draw hook means including an arm mounted for angular movement at one end of said baulk lever means, springs connected to each arm, and a draw hook at the end of said arm, said draw hook means being urged by said springs to first positions in which said hooks are located in said path of said dog means and in which said arms abut said dog means, respectively, and having second positions spaced from said paths; rotary pattern means having two sets of control projections; and a pair of follower members connected with said draw hook means, respectively, for moving the same bewteen said first and second positions, said follower members cooperating, respectively, with said sets of control projections whereby said hook means are reciprocated by said dog means.

6. A dobby comprising, in combination, a pair of dog means, each dog means having a pair of faces intersecting at a right angle; drive means for reciprocating said dog means in opposite forward and rearward strokes and including cam means, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said cam means, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means, each draw hook means including an arm mounted for angular movement at one end of said baulk lever means, springs connected to each arm, and a draw hook at the end of said arm, said draw hook means being urged by said springs to first positions in which said arms abut one of said faces of said dog means and said hooks are located forwardly of the other face of the respective dog means and in said path of said dog means, respectively, and second positions spaced from said paths; rotary pattern means having two set of control projections; and a pair of follower members connected with said draw hook means, respectively, for moving the same between said first and second positions, said follower members cooperating, respectively, with said sets of control projections whereby said hook means are reciprocated by said dog means.

7. A dobby comprising, in combination, a pair of dog means; drive means for reciprocating said dog means in opposite forward and rearward strokes and including cam means, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said cam means, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means mounted on said baulk lever means for angular movement between first positions located in said paths of said dog means, respectively, and second positions spaced from said paths; rotary pattern means having two sets of control projections; and a pair of follower members connected with said draw hook means, respectively, for moving the same between said first and second positions, said follower members having camming faces cooperating, respectively, with said sets of control projections for placing said draw hook means are placed in said first position during the forward stroke, and also during the last part of the rearward stroke of the correlated dog means whereby said hook means are reciprocated by said dog means and are already in said second position when said dog means start the forward stroke thereof.

8. A dobby comprising, in combination, a pair of dog means; drive means for reciprocating said dog means in opposite forward and rearward strokes and including a drive shaft having an axis, a pair of drive members eccentrically mounted on said drive shaft and having annular faces having axes parallel to the axis of said drive shaft equidistant from said axis, two parallelogram linkages, and a cam followier secured to each parallelogram linkage and in contact with said annular faces of said drive members, respectively, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means, each draw hook means including an arm mounted for angular movement at one end of said baulk lever means, springs connected to each arm, and a draw hook at the end of said arm, said draw hook means being urged by said springs to first positions in which said hooks are located in said path of said dog means and in which said arms abut said dog means, respectively, and having second positions spaced from said paths; and rotary pattern means including periodically moving control means and motion transmitting means actuated by said periodically movable control means of said rotary pattern means and cooperating with said draw hook means for placing each draw hook means in said first position thereof during the forward stroke and also during the last part of the rearward stroke of the correlated dog means whereby the respective hook means is reciprocated by the correlated dog means and is already in said second position thereof when the correlated dog means starts the forward stroke thereof.

9. A dobby comprising, in combination, a pair of dog means, each dog means having a pair of faces intersecting at a right angle; drive means for reciprocating said dog means in opposite forward and rearward strokes and including a drive shaft having an axis, a pair of drive members eccentrically mounted on said drive shaft and having annular faces having axes parallel to the axis of said drive shaft equidistant from said axis, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said annular faces of said drive members, respectively, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means, each draw hook means including an arm mounted for angular movement at one end of said baulk lever means, springs connected to each arm, and a draw hook at the end of said arm, said draw hook means being urged to said springs to first positions in which said arms abut one of said faces of said dog means and said hooks are located forwardly of the other face of the respective dog means and in said path of said dog means, respectively, and second positions spaced from said paths; and rotary pattern means including periodically moving control means and motion transmitting means actuated by said periodically movable control means of said rotary pattern means and cooperating with said draw hook means for placing each draw hook means in said first position thereof during the forward stroke and also during the last part of the rearward stroke of the correlated dog means whereby the respective hook means is reciprocated by the correlated dog means and is already in said second position thereof when the correlated dog means starts the forward stroke thereof.

10. A dobby comprising, in combination, a pair of dog means, each dog means having a pair of faces intersecting at a right angle; drive means for reciprocating said dog means in opopsite forward and rearward strokes and including cam means, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said cam means, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means, each draw hook means including an arm mounted for angular movement at one end of said baulk lever means, springs connected to each arm, and a draw hook at the end of said arm, roller means on said draw hooks adapted to roll on one of said faces of said dog means, said draw hook means being urged bysaid springs to first positions in which said arms abut one of said faces of said dog means and said. hooks are located forwardly of the other face of the respective dog means and in said path of said dog means, respectively, and second positions spaced from said paths; rotary pattern means having two sets of control projections; and a pair of follower members connected with said draw hook means, respectively, for moving the same between said first and second positions, said follower members cooperating, respectively, with said sets of control projections whereby said hook means are reciprocated by said dog means.

11. A dobby comprising, in combination, a pair of dog means; drive means for reciprocating said dog means in opposite forward and rearward strokes and including cam means, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact wtih said cam means, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means mounted on said baulk lever means for angular movement between first positions located in said paths of said dog means, respectively, and second positions spaced from said paths; rotary pattern means having two sets of control projections; and a pair of follower members and a pair of hook needle rods connected with said follower members, respectively, and having roller means in contact with said draw hook means, respectively, for moving the same between said first and second positions, said follower members cooperating, respectively, with said sets of control projections whereby said hook means are reciprocated by said dog means.

12. A dobby comprising, in combination, a pair of dog means, each dog means having a pair of faces intersecting at a right angle; drive means for reciprocating said dog means in opposite forward and rearward strokes and including a drive shaft having an axis, a pair of drive members eccentrically mounted on said drive shaft and having annular faces having axes parallel to the axis of said drive shaft equidistant from said axis, two parallelogram linkages, and a cam follower secured to each parallelogram linkage and in contact with said annular faces of said drive members, respectively, each of said parallelogram linkages being connected to one of the dog means so that the same are reciprocated along two paths; baulk lever means mounted for oscillatory movement; a pair of draw hook means, each draw hook means including an arm mounted for angular movement at one end of said baulk lever means, springs connected to each arm, and a draw hook at the end of said arm, roller means on said draw hooks adapted to roll on one of said faces of said dog means, said draw hook means being urged by said springs to first positions in which said arms abut one of said faces of said dog means and said hooks are located forwardly of the other face of the respective dog means and in said path of said dog means, respectively, and second positions spaced from said paths; guide means along said paths for guiding said draw hooks while located in said paths to positions in which said arms abut said dog means; rotary pattern means having two sets of control projections; and a pair of follower members and a pair of hook needle rods connected with said follower members, respectively, and having roller means in contact with said draw hooks means, respectively, for moving the same between said first and second positions, said follower members cooperating, respectively, with said sets of control projections whereby said hook means are reciprocated by said dog means.

References Cited by the Examiner UNITED STATES PATENTS 1,514,873 11/1924 Staubli 139--7l 2,071,784 2/1937 Edwards l3974 X 2,644,48 8 7/ 1953 Pfarrwaller 1397l X 2,646,080 7/1953 Kronolf 13968 3,057,379 10/1962 Staubli 139--71 FOREIGN PATENTS 538,616 3/1922 France.

15,979 18 84 Great Britain.

862,666 3 1961 Great Britain.

886,310 1/ 1962 Great Britain.

9 14,481 1/ 1963 Great Britain.

330,439 7/ 8 Switzerland.

DONALD W. PARKER, Primary Examiner.

Claims

1. A DOBBY COMPRISING, IN COMBINATION, A PAIR OF DOG MEANS MOUNTED FOR RECIPROCATING MOVEMENT ALONG TWO PATHS; DRIVE MEANS FOR RECIPROCATING SAID DOG MEANS IN OPPOSITE RECIPROCATING FORWARD AND REARWARD STROKES; BAULK LEVER MEANS MOUNTED FOR OSCILLATORY MOVEMENT; A PAIR OF DRAW HOOK MEANS MOUNTED ON SAID BAULK LEVER MEANS FOR ANGULAR MOVEMENT BETWEEN FIRST POSITIONS LOCATED IN SAID PATHS OF SAID DOG MEANS, RESPECTIVELY, AND SECOND POSITIONS SPACED FROM SAID PATHS; AND ROTARY PATTERN MEANS INCLUDING PERIODICALLY MOVING CONTROL MEANS AND MOTION TRANSMITTING MEANS ACTUATED BY SAID PERIODI-