US3285291A - Drive-mechanism in double lift dobbies - Google Patents

Description

Nov. 15, 1966 M. FAVRE DRIVE-MECHANISM IN DOUBLE LIFT DOBBIES 4 Sheets-Sheet 1 Original Filed Feb. 7, 1963 Nov. 15, 1966 FAvRE 3,285,291

DRIVE-MECHANISM IN DOUBLE LIFT DOBBIES Original Filed Feb. '7, 1965 4 sheets-Sheet 2 Nov. 15, 1966 M. FAVRE 3,285,291

DRIVE-MECHANISM IN DOUBLE LIFT DOBBIES I Original Filed Feb. 7, 1963 4 Sheets-sheet 5 Nov. 15, 1966 i VR 3,285,291

DRIVE-MECHANISM IN DOUBLE LIFT DOBBIES Original Filed Feb. '7, 1963 4 Sheets-Sheet 4 FIG. 5

United States Patent 3,285,291 DRIVE-MECHANISM IN DOUBLE LIFT DOBBIES Marcel Favre, Faverges, France, assignor to Gebr. Staubli & Co., Horgen, Zurich, Switzerland, a corporation of Switzerland Continuation of application Ser. No. 256,894, Feb. 7, 1963. This application Oct. 1, 1965, Ser. No. 498,192 7 Claims. (Cl. 13968) This is a continuation of my application Serial No. 256,894, filed February 7, 1963.

The invention relates generally to dobbies and more particularly to the construction of heald controland drive mechanism in double lift dobbies having for each heald a baulk the center of which is engaged by a jack lever.

The known double lift dobbies have for each heald two draw hooks, the engagement of which, with draw knives swinging to-and-fro, is controlled by a pattern card, and which engage on a baulk, which in turn produces the movements on a jack lever connected to the heald frame. As long as there is no draw hook engaged with the draw knives, the baulk remains supported on a stationary transverse abutment rail. There are accordingly constantly moving draw knives in operation pulling the draw hooks forward which are engaged according to the pattern card.

In the present double lift dobby the reverse method is used, the transverse abutment rail performs the operative movement of the swinging to-and-fro.

By this modification it is possible to push the heald frame into the top shed position instead of pulling the same into this position, as heretofore. The draw hooks could hitherto be provided with small attachment faces only "because of the pitch of the healds i.e. of the spacing of one heald from the other, while for the transmission of forces large attachment areas would have been of advantage. Moreover, the joints of the draw hooks on the baulks were subject to rapid wear, and between the draw hooks and the draw knife there always existed a relative movement, which led to wear of the engaging surfaces of the draw hooks and draw knife. This wear enlarged, in an uncontrollable manner, the play of engagement between the draw hooks and the draw knife, so that the faultless working of the machine was put in jeopardy, with the result that faulty picks could occur. Since in the new embodiment pusher surfaces only serve for the transmission of forces, large flat areas can be chosen, while for the controlled holding of the healds in the top shed position suspension on small areas suffices.

The present double lift dobby has for each heald a baulk at the center of which there is engaged a jack lever. The dobby is characterized by the fact that each end of the individual baulks has an opposite end portion comprising a flat abutment surface engaged by flat surfaces on abutment rails swinging to-and-fro abutting and actuating the same. Attachment members for a controllable arrester hook are pivotally mounted on a fixed angle. Depending on the control of the pattern card of the associated arrester hook, one or the other end of a baulk or none of them is held fast so that it either says put while the abutment rail swings backwards or goes back with the abutment rail. Each heald frame is articulated by means of a jack lever to a respective baulk and is pushed to a top shed position by the thrust of the opposite abutment rail when the end of the baulk is held fast or stays in the bottom shed position as long as no attachment hook is engaged.

Embodiments of the present invention are illustrated, by way of example, in the accompanying drawing, in which:

FIG. 1 is a diagrammatic illustration of a heald control ice and drive mechanism embodying the invention and illustrates mechanism in position for positioning loom healds in top shed and bottom shed positions;

FIG. 2 is a drive-mechanism for transverse pusher rails of FIG. 1;

FIGS. 3 and 4 are diagrammatic illustrations of two modified embodiments of the heald control and drive mechanism of FIG. 1, wherein the transverse rails, baulk ends and arrester hooks show different constructions;

FIG. 5 is a diagrammatic illustration of solenoids controlling levers for the lower hooks and illustrates the solenoids for upper hooks arranged behind those for the lower hooks.

The control and drive mechanism for each of the loom heald frames, not shown, consists in a baulk 1, at each end of which an attachment hook 2a, 2b respectively, is pivotally attached. At the middle of the baulk is engaged a jack lever 3. The needle system forward of the mechanism comprises a pattern card 4, which controls reading needles 5 and draw needles 6. The latter may enter into operative engagement with the draw rails 7, whereby a lever arm 8a, 8b respectively, is lifted off an abutment 10 against the bias of a respective spring 9a, 9b. The lever arms 8a, 8b respectively, form parts of arrester hooks 11a, 11b respectively, which are pivotally mounted on pivots 12a, 12b respectively.

Flat abutment surfaces 13a, 13b respectively, are provided on the hooks 2a, 2b and are contacted by flat surfaces on transverse abutment rails 14a, 14b respectively. As shown in FIG. 2, these transverse rails are attached to a rocker lever 16, which is pivoted about its pivot 15, and are driven from a cam 18 through a connecting rod 17. The center of the axis 15 of the rocker lever 16 preferably coincides with the virtual pivot point of the jack lever on the baulk in the bottom shed position of the corresponding heald. The cam 18 is mounted on a drive shaft 19 of the dobby or on a shaft coupled therewith. The connecting rod 17 is pivotally connected on the one hand at 27 to the rocker lever 16, and on the other hand is articulated to the stationary axle 22 by means of a pin 20 and a guide lever 21. It carries two rollers or followers 23 and 24, which contact the cam 18 preferably in such a manner, that the straight line connecting their centers passes through the center of rotation of the cam.

In the various figures the primed references denote either the second position-drawn in chain-dotted lines --of the corresponding component having an unprimed similar reference, or can be considered to indicate the position of the next heald frame controland drivemechanism for another heald frame lying immediately behind which would be in such a position. In FIGS. 1, 3 and 4 of the drawings the heald operating mechanism in front is illustrated in a position for controlling the top shed position of the heald frame, and the mechanism behind it in the position for controlling the bottom shed position of the heald.

The control and drive mechanism operates as follows: The normal position of the heald is its bottom shed position, which in the drawings corresponds to the position 3 of the jack lever 3. The hooks 2a and 2b on the ends of the baulks contact the transverse rails 14a, 1411. Since the pivot axis of the rocker lever 16 coincides with the axis of engagement of the jack lever on the baulk, the jack lever in its position 3 remains in stationary position while the hooks are disengaged and transverse rails perform their swinging movements during this time. In order that the baulk movement thus generated may not be disturbed, the lever arms 8a, 8b, are pulled towards the left, by the draw rails 7 through the draw needles 6, so that the arrester hooks 11a do not come into engagement with the attachment hooks 2a, and the arrester hooks 1112 not into engagement with the attachment hooks 2b. When the heald frame is to be raised into the top shed position, the draw needles are so controlled that they are not engaged by the draw rails 7. Under the action of the springs 9a and 9b, the lever arms 8a and 8b abut the abutment 10. Firstly, the transverse abutment rail pushes the attachment hook 2b into its position illustrated, where it is detained by the arrester hook 11b. The safety rail 25b prevents the headof the hook 2b from being deflected. The transverse abutment rail 1412 then moves back unloaded in its swinging movement, while at the same time the other transverse abutment rail moves from its position 14a towards the position 14a and thus pushes the attachment hook 2a ahead of itself. This pushing effects, through the baulk 1 and the jack 3, the pulling up of the heald. The attachment hook 2a can then engage into the arrester hook 11a, or itis heldin the position illustrated by the transverse abutment rail. The safety rail 25a prevents any deflection of the attachment hook 2a. With the hooks 2a and 2b engaged, it is possible to hold the heald frame in the top shed position during several working cycles.

As mentioned herein above, the continuous swinging movement of the rocker lever 16 with the transverse abutment rails 14a and 14b is derived from the eccentric 18, which moves the two rollers 23 and 24 with the connecting rod 17 to-and-fro relative to the fixed axles 22 and 15. One oscillation of the rocker lever 16 will effect one working cycle of operation of a heald.

The positions of the draw needles 6 are controlled by the pattern card 4. The wires 28, the reading needles .5,

attached to the draw needles 6, are lifted off the pattern card so that the latter can be advanced by one or two picks. Afterwards the wires 28 let the reading needles down and according to the pattern card they remain on the pattern card or fall into a hole of the pattern card thus positioning the draw needles 6 with respect to the draw rails 7.

The jack levers move about the shaft 26.

The control of the lever arms 8a, 8b respectively, and accordingly also that of the arrester hooks 11a, 11b respectively, may be effected, electromagnetically as illustrated diagrammatically in FIG. 5 instead of by the needle system described herein above. In this embodiment the lever arms 58a, 58b on pivots 512a, 512k and biased by I springs 59a, 5% are comparable to the lever arms 8a, 8b.

Solenoids 38, 39 have armatures 42, 43 respectively, which they attract when energized in the direction of the arrows A and B respectively, against spring bias. The circuits of the solenoids 38, 39 are controlled on the one hand, by make-and- break switches 36, 47 respectively, which are actuated from a pattern card 44 through needle stems 45, and on the other hand by a three position switch 48 operated from a cam disc 50 through a stem 49.

This cam, which is driven uniformly by the main drive of the loom in the direction of the arrow C, has a recess 51 and a radial projection 52 following one another immediately in the sense of rotation. In the position shown in FIG. 5, the stem 49 has dropped into the recess 51, and the switch 48 accordingly closes the circuit of the solenoid 40 which is also closed by the switch 36, whose needle 45 has dropped into a hole of the pattern card 44.

Immediately afterwards the stem 49 is raised by the projection 52, and switch 48 closes the circuit of the solenoid 39, which is also closed by the switch 47 whose needle 45 has dropped into a hole of the pattern card 44. When the needles 45 does not drop into holes of the pattern card 44, the switches 46, 47 respectively, are in the open position shown in dotted lines.

When the stem 49 slides on the cylindrical circumference of the cam 50, the switch 48 is in the middle position in which the circuits of both solenoids 38, 39 are interrupted.

The switching over from the circuit of one solenoid to that of the other takes place at the moment when the transverse abutment rails 14a, 1412 are in the full-line position of FIG. 1, i.e. when the hooks 2a are to be engaged or to be disengaged. By the components shown, the odd numbered picks are effected, and by the components arranged behind them (not visible) the even numbered picks.

The jack levers move about the shaft 26.

The modified embodiment according to FIG. 3 likewise shows the baulk 31 in the top shed position and in the bottom shed position 31'. Each end of the baulk itself is in turn formed on the one hand as a hook 329a or 32%, and operable to the position 3291: respectively, and on the other hand as a flat abutment surface 330a, position-able in position 330a, or 33Gb positionable in position 33%, respectively, for the transverse abutment rails 331a, 331b respectively. The transverse rails 331a, 331b respectively, have a square profile, and consist of individual cubes rotatably mounted on the shaft 332a, 3321) respectively, swung to-and-fro by the rocker lever, in order that the same may accommodate themselves at any time to the surfaces 330a, 33Gb respectively. For each end of a baulk one such cube is provided. The mechanism comprises an abutment 410 comparable to abutment 10 in FIG. 1.

The arrester hooks 311a, 311b, the hook portion of 'which is formed complementary to the shape of the hooks 329a, 3291;, conform in their construction as well as in their function with the arrester hooks 11a, 11b, according to FIG. 1. The lever arms 38a, 38b, the springs 39a, 3%, the abutment 19, the axles 312a, 312b, as well as the draw needles 36 will be recognized as having equivalents in FIG. 1. The shaft, about which the jack levers swing, is denoted 326.

In the embodiment according to the FIGURE 4 the baulk 41 operable to the position 41' is composed of two plates lying parallel to one another at a distance. The plates are connected with one another at the ends of the baulk by means of pins 433a, or 433]), shown in its other position 433b. These pins serve at the same time as the attachment members of the baulk ends for the arrester hooks 411a, 411b, the arrester portion of which is shaped accordingly. The hooks are pivoted on shafts 412a, 412b. The construction of the transverse abutment rails 431a, 431b rotatable on shafts 432a, 432b conforms with that according to FIG. 3. The rails bear on flat surfaces 430a, 4301) to move them to positions such as 43012. The mechanism comprises drawer needles 46 and lever arms 48a, 48b operable to positions 48a, 48b. The lever arms are biased by springs 49a and 4911 as shown and an abutment 410 and shaft 426 are provided and correspond to the abutment 10 and shaft 26 before described.

As distinguished from the known control-and-drive mechanisms of the heald frames the movements of the heald frames are effected by pushing theends of the baulks instead of pulling the same. Thereby, it has been made possible to make the contact surface area larger, which results in reduced wear. The stationary arrester hooks 411a, 411b, merely hold the pushed ends of the baulks. Such holding requires, however, a much smaller contact area, the engagement which can moreover be effected with less loss of time. There are accordingly large pusher areas and small holding areas, which allow a quick engagement. With the known mechanism, the draw hooks perform a double function, namely controlling and pulling, which requires an appropriate construction.

The mechanism illustrated and described, may operate in the forward and in the reverse run without missing a pick. By the large abutment surface it is made possible to transmit those increased forces which arise at a higher speed.

A further advantage-results from the positive control of all components, which in turn permits an increased speed of the working cycles, particularly as compared with mechanisms operating on gravity.

As compared with the known embodiments the machine described shows considerable simplifications. While in the former double lift dobbies, for raising the healds the hooks mounted in the baulk ends had to be controlled with respect to the draw knives, a considerable simplification of the operative components is attained by the new embodiment. Instead of fixed transverse rails serving as abutments for the baulk in the basic position of the healds, and instead of the draw knives, which pull the draw hooks out, in the dobby according to the invention only transverse rails are required, which push and detain the baulks.

. Bythe invention as described above, the stationary transverse rails as well as the draw knives and the actuating mechanism for the engagement of the draw hooks on the draw knives are replaced by the new swinging transverse rails and by arrester hooks thus simplifying the whole dobby mechanism. By this simplification a more accurate and quick working cycle is made possible.

Also as regards the needle system arranged ahead of the mechanism, there exists simplification since this system acts directly on the arrester hooks, so that also from the control side nothing stands in the way of an increase of the working speed.

It is characteristic for this new dobby that the heald frame is in its bottom position when one end of the baulk is in its rear position while the other end is in its pushed out position, in other words, the baulk has an inclined position when the heald frame is down and the baulk stands upright when the heald frame is in the top shed. This is just contrary to the old type of dobbies, where the baulk stays upright, reposing against the fixed transverse rails, when the heald frame is in the bottom shed and the baulk changes into the inclined position when the heald frame is brought to the top shed. The new type of dobby is quite clearly shown in FIGURE 1.

What I claim and desire to secure by Letters Patent is:

1. For use in a loom having pattern means comprising instructions to control a top shed position and a bottom shed position, a double lift dobby comprising jack levers operable to a first and a second operative position corresponding to positions for effecting control of a top shed position and a bottom shed position, a baulk for each jack lever for actuating a respective jack lever to said two operative positions alternately and having two opposite end portions each operable to two operative positions, rail means having fiat surfaces cyclically actuated between two positions for pushing on the opposite end portions alternately for actuating each baulk between said two operative positions, means for driving said rail means in operation, paired arrester hooks pivotally mounted for engaging other pivoted hook means mounted on said baulk means for holding a respective end portion of said baulk to hold it in one of said positions, and for freeing said end portions to allow said baulk to move to the other of said positions and said other pivoted hook means on said baulk presenting substantially fiat engagement surfaces for said rail means flat surfaces to eliminate sliding frictional contact between the engaging surfaces.

2. For use in a loom having pattern means comprising instructions to control a top shed position and a bottom shed position, a double lift dobby comprising jack levers operable to a first and a second operative position corresponding to positions for effecting control of a top shed position and a bottom shed position, a baulk for each jack lever for actuating a respective jack lever to said two operative positions alternately and having two opposite end portions each operable to two operative positions, rail means having flat surfaces cyclically actuated between two positions for pushing on said opposite end portions alternately for actuating each baulk between said two operative positions, means for driving said rail means in operation, paired arrester hooks pivotally mounted for engaging and holding a respective end portion of said baulk to hold it in one of said positions and for freeing said end portions to allow said baulk to move to the other of said positions, pivoted means on said baulk presenting substantially flat engagement surfaces for said rail means flat surfaces to eliminate sliding frictional contact between the engaging surfaces, and means for pivotally actuating said arrester hooks during actuation of said rail means for engaging said end portions of a respective baulk alternately and for causing said arrester hooks to free said end portions in a sequence determined by said pattern means.

3. A double lift dobby according to claim 2, in which said pivoted means on said baulk comprise hooks for cooperating with respective ones of said arrester hooks for holding a respective end portion of said baulk.

4. For use in a loom having pattern means comprising instructions to control a top shed position and a bottom shed position, a double lift dobby comprising jack levers operable to a first and a second operative position corresponding to positions for elfecting control of a top shed position and a bottom shed position, a baulk for each jack lever for actuating a respective jack lever to said two operative positions alternately and having two opposite end portions having flat surfaces thereon and each operable to two operative positions, rail means cyclically actuated between two positions for pushing on the opposite end portions alternately for actuating each baulk between said two operative positions, means for driving said rail means in operation, paired arrester hooks pivotally mounted for engaging and holding a respective end portion of said baulk to hold it in one of said positions and for freeing said end portions to allow said baulk to move to the other of said positions, pivoted means on said rail means presenting substantially fiat engagement surfaces for said baulk flat surfaces to eliminate sliding frictional contact between the engaging surfaces.

5. For use in a loom having pattern means comprising instructions to control a top shed position and a bottom shed position, a double lift dobby comprising jack levers operable to a first and a second operative position corresponding to positions for effecting control of a top shed position and a bottom shed position, a baulk for each jack lever for actuating a respective jack lever to said two operative positions alternately and having two opposite end portions each operable to two operative positions, rail means having flat surfaces cyclically actuated between two positions for pushing on the opposite end portions alternately for actuating each baulk between said two operative positions, means for driving said rail means in operation, paired arrester hooks pivotally mounted for engaging and holding a respective end portion of said baulk to hold it in one of said positions and for freeing said end portions to allow said baulk to move to the other of said positions, pivoted means on said rail means presenting substantially flat engagement surfaces for said baulk flat surfaces to eliminate sliding frictional contact between the engaging surfaces and means for pivotally actuating said arrester hooks during actuation of said rail means for engaging said end portions of a respective baulk alternately and for causing said arrester hooks to free said end portions in a sequence determined by said pattern means.

6. For use in a loom having pattern means comprising instructions to control a top shed position and a bottom shed position, a double lift dobby comprising jack levers operable to a first and a second operative position corresponding to positions for effecting control of a top shed position and a bottom shed position, a baulk for each jack lever for actuating a respective jack lever to said two operative positions alternately and having two opposite end portions having flat surfaces thereon and each operable to two operative positions, rail means cyclically actuated between two positions for pushing on the opposite end portions alternately for actuating each baulk between said two operative positions, means for driving said rail means in operation, paired arrester hooks pivotally mounted for engaging and holding a respective end portion of said baulk to hold it in one of said positions and for freeing said end portions to allow said baulk to move to the other of said positions, pivoted means on said rail means presenting substantially flat engagement surfaces for said baulk flat surfaces to eliminate sliding frictional contact between the engaging surfaces, means for pivotally actuating said arrester hooks during actuation of said rail means for engaging said end portions of a respective baulk alternately and for causing said arrester hooks to free said end portions in a sequence determined by said pa ttern means, and pivoted means on said rail means comprising pivotally mounted elements having a plurality of opposed sides defining said flat surfaces on said baulk.

7. For use in a loom having pattern means comprising instructions to control a top shed position and a bottom shed position, a double lift dobby comprising jack levers operable to a first and a second operative position corresponding to positions for effecting control of a top shed position and a bottom shed position, a baulk for each jack lever for actuating a respective jack lever to said two operative positions alternately and having two opposite end portions each operable to two operative positions, rail means having flat surfaces cyclically actuated between two positions for pushing on the opposite end portions alternately for actuating each baulk between said two operative positions, means for driving said rail means in operation, paired arrester hooks pivotally mounted for engaging and holding a respective end portion of said baulk to hold it in one of said positions and for freeing said end portions to allow said baulk to move to the other of said 5 positions, said baulk presenting substantially flat engagement surfaces for said rail means flat surfaces and means operative to eliminate sliding frictional contact between said engaging surfaces.

References Cited by the Examiner UNITED STATES PATENTS MERVIN STEIN, Primary Examiner.

ROBERT R. MACKEY, H. S. JAUDON,

Assistant Examiners.

Claims (1)

1. FOR USE IN A LOOM HAVING PATTERN MEANS COMPRISING INSTRUCTIONS TO CONTROL A TOP SHED POSITION AND A BOTTOM SHED POSITION, A DOUBLE LIFT DOBBY COMPRISING A JACK LEVERS OPERABLE TO A FIRST AND A SECOND OPERATIVE POSITION CORRESPONDING TO POSITIONS FOR EFFECTING CONTROL OF A TOP SHED POSITION AND A BOTTOM SHED POSITION, A BAULK FOR EACH JACK LEVER FOR ACTUATING A RESPECTIVE JACK LEVER TO SAID TWO OPERATIVE POSITIONS ALTERNATELY AND HAVING TWO OPPOSITE END PORTIONS EACH OPERABLE TO TWO OPERATIVE POSITIONS, RAIL MEANS HAVING FLAT SURFACES CYCLICALLY ACTUATED BETWEEN TWO POSITIONS FOR PUSHING ON THE OPPOSITE END PORTIONS ALTERNATELY FOR ACTUATING EACH BAULK BETWEEN SAID TWO OPERATIVE POSITIONS, MEANS FOR DRIVING SAID RAIL MEANS IN OPERATION, PAIRED ARRESTER HOOKS PIVOTALLY MOUNTED FOR ENGAGING OTHER PIVOTED HOOK MEANS MOUNTED ON SAID BAULK MEANS FOR HOLDING A RESPECTIVE END PORTION OF SAID BAULK TO HOLD IT IN ONE OF SAID POSITIONS, AND FOR FREEING SAID END PORTIONS TO ALLOW SAID BAULK TO MOVE TO THE OTHER OF SAID

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