Title of Invention	A DEVICE FOR LEVELLING THE POSITION OF THE FRAMES OF A LOOM FITTED WITH A CAM WEAVE MECHANISM
Abstract	The invention relates to a weaving machine which is fitted with a cam harness mounting mechanism (10), wherein the frames are actuated by oscillating levers (11) provided with cam followers (19A) and mounted on a common shaft (15) whereby the position thereof can be varied in relation to the frame (16) with the aid of at least one eccentric (17). The angular orientation of said eccentric (17) is controlled with the aid of a motorization unit (40, 41) which is articulated (en 42) on the frame (16) about an axis (X42) which is globally parallel to the pivoting axis (X17) of the eccentric 1 (17), and the output shaft of the motorization unit (40, 41) is rotationally coupled to or formed by, a threaded rod (46) which is engaged in a plate nut (50) of a maneuvering arm (6) of the eccentric (17).

Title of Invention

A DEVICE FOR LEVELLING THE POSITION OF THE FRAMES OF A LOOM FITTED WITH A CAM WEAVE MECHANISM

Abstract

The invention relates to a weaving machine which is fitted with a cam harness mounting mechanism (10), wherein the frames are actuated by oscillating levers (11) provided with cam followers (19A) and mounted on a common shaft (15) whereby the position thereof can be varied in relation to the frame (16) with the aid of at least one eccentric (17). The angular orientation of said eccentric (17) is controlled with the aid of a motorization unit (40, 41) which is articulated (en 42) on the frame (16) about an axis (X42) which is globally parallel to the pivoting axis (X17) of the eccentric 1 (17), and the output shaft of the motorization unit (40, 41) is rotationally coupled to or formed by, a threaded rod (46) which is engaged in a plate nut (50) of a maneuvering arm (6) of the eccentric (17).

Full Text	LEVEL ADJUSTMENT DEVICE, CAM WEAVE MECHANISM INCORPORATING SAID DEVICE AND WEAVING MACHINE FITTED WITH SAID MECHANISM The invention relates to a device for leveling the position of the frames of a loom fitted with a cam weave mechanism. The invention also relates to a weave mechanism comprising such a device and to a loom fitted with such a mechanism. In the field of looms, cam weave mechanisms are known that comprise a series of oscillating levers in numbers equal to those of the heddle frames to be mounted on the loom, each oscillating lever being designed to be coupled to one of the frames and fitted with two rollers which interact with the two tracks of a matching cam rotated by a common shaft. During certain operations of maintenance or adjustment of a loom, it is necessary to bring all the loom frames to one and the same level. Such is the case, in particular, when it is necessary to repair broken warp threads. To do this, it is known from EP-A-0 580 528 to mount the various levers with rollers on an eccentric and to rotate this eccentric to bring the various levers into a common position called the leveling position. In this type of device, the rotation of the eccentric is controlled by a motor equipped with a reduction gear having a spur pinion or by a worm-gear reducer. The reduction ratio of these items of equipment must be high, which requires the use of several reduction stages for reduction gears with spur pinions. For a worm-gear reducer, such an item of equipment is bulky, complex and awkward to adjust. In all cases, these reducers are relatively costly. It is these disadvantages that the invention intends more particularly to remedy by proposing a leveling device that is particularly simple to construct and use and making it possible to move with good precision the various roller levers of a cam weave mechanism. With this in mind, the invention relates to a device for leveling the position of the frames of a loom fitted with a cam weave mechanism, these frames being actuated by oscillating levers provided with cam followers and mounted on a common shaft whose position relative to the frame of the mechanism can be varied by means of at least one eccentric. This device is characterized in that the angular orientation of the eccentric is controlled by means of a drive assembly articulated on the frame about an axis globally parallel with the pivoting axis of the eccentric, the output shaft of this drive assembly being fixedly attached in rotation with, or formed by, a threaded rod engaged in a captive nut of a maneuvering arm of the eccentric. Thanks to the invention, the threaded rod rotated by the motor acts directly on the captive nut of the maneuvering arm which has the effect of rotating this maneuvering arm about the pivoting axis of the eccentric, that is to say of controlling the positioning of the common shaft of the oscillating roller levers along its trajectory in an arc of a circle imposed by the eccentric. According to advantageous but not obligatory aspects of the invention, a leveling device may incorporate one or more of the following features: - The nut is articulated relative to the maneuvering arm, at least about an axis globally parallel with the pivoting axis of the eccentric. - The maneuvering arm is provided with a surface for pressing against an end-of-travel stop when the eccentric is in a position compatible with the use of the weave mechanism for weaving. - A member driven by the eccentric is capable of pressing against an end-of-travel stop when the levers are in the leveling position. In this case, this member is advantageously fixedly attached to the maneuvering arm. - The end-of-travel stop is fitted with means for detecting the pressure of the arm or of the aforementioned member in one of the aforementioned positions. - In the configuration for using the weave mechanism for weaving, the geometric axis of the shaft common to the levers, the geometric axis of the drive shaft of the cams and the geometric pivoting axis of the eccentric are substantially parallel and coplanar. This aspect of the invention is conducive to good stability of the weave mechanism in the weaving configuration. - The shaft common to the lever is supported relative to the frame by means of two eccentrics each placed in the vicinity of one of its ends. The invention also relates to a cam weave mechanism for a loom that comprises a leveling device as described hereinabove. Such a mechanism is more economical, more reliable and easier to use, particularly for leveling the frames of the loom, than the known items of equipment. Finally the invention relates to a loom fitted with a weave mechanism as mentioned hereinabove. Such a loom is easier to use than those of the prior art. The invention will be better understood and other advantages of the latter will appear more clearly in the light of the following description of a loom and a weave mechanism fitted with a leveling device according to the invention, given solely as an example and made with reference to the appended drawings in which: - figure 1 is a partial schematic representation of the principle of a loom according to the invention; - figure 2 is a schematic representation on a larger scale of the weave mechanism of the loom of figure 1 in the weaving configuration; - figure 3 represents some parts of the mechanism of figure 2 when the latter switch from a weaving configuration to a leveling configuration; - figure 4 is a view similar to figure 3, when the mechanism is in the leveling configuration; - figure 5 is a view on a larger scale of detail V in figure 2; - figure 6 is a view on a larger scale of detail VI in figure 4 and - figure 7 is a view in perspective of some elements forming the leveling device of the mechanism represented in figures 2 to 6. The loom M shown in figure 1 comprises several heddle frames only one of which is shown in figure 1 with reference number 1. The various frames of the loom M operate in a vertical oscillation movement shown by the double arrow Fi and imparted by a cam mechanism 10 whose output levers 11 act respectively on connecting rods 12 associated with bent levers 13 connected together and to the frame 1 by connecting rods 14. The levers 11 are provided in a number equivalent to the number of heddle frames 1 and mounted so as to pivot, as shown on the double arrow F2, about the longitudinal axis of a common shaft 15 held by the frame 16 of the mechanism 10. The shaft 15 is fitted, at its two ends, with two eccentrics 17 and 17' that themselves support the shaft 15 and that are supported by two bearings, not shown, defined by the frame 16. The mechanism 10 also comprises several matching cams 18 whose twin tracks 18A and 18B are pressed upon by the rollers 19A and 19B of one and the same lever 11. Thus, each lever 11 follows a movement imposed by the geometry of the tracks 18A and 18B of the cam 18 with which it is associated. A ring and pinion assembly 20 is mounted at the end of the shaft 21 common to the cams 18. For the clarity of the drawing, the ring and pinion assembly 20 is shown only in figures 1 and 2. A cover 16B mounted on the frame 16 and represented by its silhouette in dot-and-dash lines only in figures 1 and 2 makes it possible to isolate the elements 15 to 21 from the outside. In figure 2, the track of the shaft 15 is shown in dot- and-dash lines and its geometric axis is referenced X15. In the same manner, one notes X17 the geometric pivoting axis of the eccentrics 17 and 17' and X21 the geometric axis of the shaft 21. These axes are globally parallel with one another. In the weaving configuration represented in figure 2, in which the oscillating levers 11 are designed to drive the heddle frames 1 and equivalents, the axes X15 and X17 and X21 are coplanar, which means that the separating forces between the shafts 15 and 21 resulting from the action of the cams on the levers do not tend to rotate the eccentric 17 and to load its control device. When the user requires to level the frames 1, he must bring the levers 11 to the configuration of figure 4 in which the rollers 19A and 19B are separated from the cams 18 and in which the levers 11 all have the same angular position relative to the axis X15. To do this, an electric motor 40 is mounted on a support 41 articulated about an axis X42 defined by two bearings, only one of which is visible in figure 2 with reference number 42, these bearings being supported by a mid-part 16A of the frame 16. The axis X42 is globally parallel with the axes X15, X17 and X21. Thus, the assembly formed by the elements 40 and 41 may pivot about the axis X42 as shown by the double arrow F3. The output shaft 40A of the motor 40 is received in a sleeve 43 held, thanks to a bearing 44, in the support 41. A pin 45 makes it possible to combine the shaft 40A and the sleeve 43 in rotation. Furthermore, a threaded rod 46 is engaged in the sleeve 43 and fixedly attached in rotation to the latter thanks to a cotter 47. Thus, the threaded rod can be rotated by the motor 40 in a direction that depends on the supply current of the motor 40. As a variant, the output shaft of the motor 40 could protrude outside the support 41 and be threaded. A nut 50, whose tapping is adapted to the thread of the rod 46, is mounted on this rod and held captive at the end of a maneuvering arm 60 fixedly attached to the eccentric 17 and extending substantially in a radial direction relative to the axis X17. The arm 60, which makes it possible to exert a torque to rotate the eccentric 17 about the axis X17, comprises a main part 60A and a plate 60B fitted to the part 60A. The nut 50 is held in a yoke between the elements 60A and 60B. It is provided with two trunnions, only one of which is visible with reference number 61, that are engaged in the corresponding bores of the elements 60A and 60B, so that the nut 50 is articulated relative to the arm 60 about an axis X61 substantially parallel with the axes X15, X17, X21 and X42. It should be noted that the plate 60B is not shown in figures 2 to 6 for clarity of the drawing. When it is necessary to move the various oscillating levers 11 toward their leveling position, the motor 40 is actuated to drive the threaded rod 46 in a rotary direction R causing the nut 50 to move in the direction of the support 41, as shown by the arrow F4. The effect of this movement is to rotate the arm 60 and the eccentric 17 in the direction of the arrow F5, which has the effect of rotating, in the same direction, the geometric axis X15 about the geometric axis X17 thus moving the shaft 15 away from the shaft 21 in a trajectory in an arc of a circle C represented in dot- and-dash lines in figure 3. Passing through the intermediate position of figure 3, it is therefore possible to reach the position of figure 4 in which all the rollers 19A and 19B of the levers 11 are disengaged from the cams 18, the levers being in line, so that the frames 1 are also in line. The fact that the assembly formed by the motor 40 and the support 41 is mounted so as to oscillate about the axis X42 makes it possible to achieve the various orientations necessary for the threaded rod 46 during the upward movement of the nut 40 along this rod and in the direction of the support 41, these various orientations originating from the variation in the horizontal distance d between the central axis X46 of the rod 46 and the axis X17. A stop 70 is mounted on the frame 16 and supports a contact switch 71 provided with a rod 72 against which a surface 62 of the arm 60 presses, as shown in figure 5. This makes it possible to detect that the eccentrics 17 and 17' are really in an end-of-travel position in which the rollers of the various levers 11 are in a position of reduced clearance with the twin tracks of the associated cams 18. When the switch 71 is actuated, the supply of the motor 40 is interrupted and weaving can take place. In addition, the arm 60 is extended by an extension 63 diametrically opposed to the end of the arm 60 on which the nut 50 swivels and which presses against a surface 73 of the stop 70 in the configuration of figure 4. According to a variant of the invention that is not shown, a switch of the type of the switch 71 may be provided on the stop 70 to detect the fact that the weave mechanism is in the leveling configuration. The invention is not limited to the single embodiment described and may, in particular, be used with the devices shown in figures 2 and 5 of EP-B-0 580 528. According to a variant, not shown, of the invention, the axis of articulation of the drive assembly may be situated on the opposite side of the motor output shaft relative to this motor, that is to say, in the representation of the figures, above the motor. CLAIMS 1. A device for leveling the position of the frames of a loom fitted with a cam weave mechanism, said frames being actuated by oscillating levers provided with cam followers and mounted on a common shaft whose position relative to the frame of the mechanism can be varied by means of at least one eccentric, characterized in that the angular orientation of said eccentric (17, 17') is controlled by means of a drive assembly (40, 41) articulated (at 42) on said frame about an axis (X42) globally parallel with the pivoting axis (X17) of said eccentric, the output shaft (40A) of said drive assembly being fixedly attached in rotation with, or formed by, a threaded rod (46) engaged in a captive nut (50) of a maneuvering arm (60) of said eccentric (17). 2. The device as claimed in claim 1, characterized in that said nut (50) is articulated relative to said maneuvering arm (60) at least about an axis (X61) globally parallel with said pivoting axis (X17) of said eccentric (17, 17'). 3. The device as claimed in one of the preceding claims, characterized in that said maneuvering arm (60) is provided with a surface (62) for pressing against an end-of-travel stop (70) when said eccentric (17, 17') is in a position (figures 2, 5) compatible with the use of the weave mechanism (10) for weaving. 4. The device as claimed in one of the preceding claims, characterized in that it comprises a member (63) driven by said eccentric (17) and capable of pressing against an end-of-travel stop (73) when said levers (11) are in the leveling position (figures 4 and 6). 5. The device as claimed in claim 4, characterized in that said member (63) is fixedly attached to said maneuvering arm (60). 6. The device as claimed in one of claims 3 to 5, characterized in that said stop (70, 73) is fitted with means (71) for detecting the pressure of said arm (60) or of said member (63) in said position. 7. The device as claimed in one of the preceding claims, characterized in that, in the configuration for using the weave mechanism for weaving (figures 2, 5), the geometric axis (X15) of the shaft (15) common to said levers (11), the geometric axis (X21) of the drive shaft (21) of said cams (20) and the geometric pivoting axis (X17) of said eccentric (17, 17') are substantially parallel and coplanar. 8. The device as claimed in one of the preceding claims, characterized in that said shaft (15) common to said levers (11) is supported relative to said frame (16) by means of two eccentrics (17, 17') each placed in the vicinity of one of its ends. 9. A cam weave mechanism (10) for a loom, characterized in that it comprises a leveling device (40-72) as claimed in one of the preceding claims. 10. A loom (M) fitted with a weave mechanism (10) as claimed in claim 9. The invention relates to a weaving machine which is fitted with a cam harness mounting mechanism (10), wherein the frames are actuated by oscillating levers (11) provided with cam followers (19A) and mounted on a common shaft (15) whereby the position thereof can be varied in relation to the frame (16) with the aid of at least one eccentric (17). The angular orientation of said eccentric (17) is controlled with the aid of a motorization unit (40, 41) which is articulated (en 42) on the frame (16) about an axis (X42) which is globally parallel to the pivoting axis (X17) of the eccentric 1 (17), and the output shaft of the motorization unit (40, 41) is rotationally coupled to or formed by, a threaded rod (46) which is engaged in a plate nut (50) of a maneuvering arm (6) of the eccentric (17).

Full Text

LEVEL ADJUSTMENT DEVICE, CAM WEAVE MECHANISM
INCORPORATING SAID DEVICE AND WEAVING MACHINE FITTED
WITH SAID MECHANISM
The invention relates to a device for leveling the
position of the frames of a loom fitted with a cam
weave mechanism. The invention also relates to a weave
mechanism comprising such a device and to a loom fitted
with such a mechanism.
In the field of looms, cam weave mechanisms are known
that comprise a series of oscillating levers in numbers
equal to those of the heddle frames to be mounted on
the loom, each oscillating lever being designed to be
coupled to one of the frames and fitted with two
rollers which interact with the two tracks of a
matching cam rotated by a common shaft. During certain
operations of maintenance or adjustment of a loom, it
is necessary to bring all the loom frames to one and
the same level. Such is the case, in particular, when
it is necessary to repair broken warp threads.
To do this, it is known from EP-A-0 580 528 to mount
the various levers with rollers on an eccentric and to
rotate this eccentric to bring the various levers into
a common position called the leveling position. In this
type of device, the rotation of the eccentric is
controlled by a motor equipped with a reduction gear
having a spur pinion or by a worm-gear reducer. The
reduction ratio of these items of equipment must be
high, which requires the use of several reduction
stages for reduction gears with spur pinions. For a
worm-gear reducer, such an item of equipment is bulky,
complex and awkward to adjust. In all cases, these
reducers are relatively costly.
It is these disadvantages that the invention intends

more particularly to remedy by proposing a leveling
device that is particularly simple to construct and use
and making it possible to move with good precision the
various roller levers of a cam weave mechanism.
With this in mind, the invention relates to a device
for leveling the position of the frames of a loom
fitted with a cam weave mechanism, these frames being
actuated by oscillating levers provided with cam
followers and mounted on a common shaft whose position
relative to the frame of the mechanism can be varied by
means of at least one eccentric. This device is
characterized in that the angular orientation of the
eccentric is controlled by means of a drive assembly
articulated on the frame about an axis globally
parallel with the pivoting axis of the eccentric, the
output shaft of this drive assembly being fixedly
attached in rotation with, or formed by, a threaded rod
engaged in a captive nut of a maneuvering arm of the
eccentric.
Thanks to the invention, the threaded rod rotated by
the motor acts directly on the captive nut of the
maneuvering arm which has the effect of rotating this
maneuvering arm about the pivoting axis of the
eccentric, that is to say of controlling the
positioning of the common shaft of the oscillating
roller levers along its trajectory in an arc of a
circle imposed by the eccentric.
According to advantageous but not obligatory aspects of
the invention, a leveling device may incorporate one or
more of the following features:
- The nut is articulated relative to the maneuvering
arm, at least about an axis globally parallel with
the pivoting axis of the eccentric.
- The maneuvering arm is provided with a surface for
pressing against an end-of-travel stop when the
eccentric is in a position compatible with the use of

the weave mechanism for weaving.
- A member driven by the eccentric is capable of
pressing against an end-of-travel stop when the
levers are in the leveling position. In this case,
this member is advantageously fixedly attached to the
maneuvering arm.
- The end-of-travel stop is fitted with means for
detecting the pressure of the arm or of the
aforementioned member in one of the aforementioned
positions.
- In the configuration for using the weave mechanism
for weaving, the geometric axis of the shaft common
to the levers, the geometric axis of the drive shaft
of the cams and the geometric pivoting axis of the
eccentric are substantially parallel and coplanar.
This aspect of the invention is conducive to good
stability of the weave mechanism in the weaving
configuration.
- The shaft common to the lever is supported relative
to the frame by means of two eccentrics each placed
in the vicinity of one of its ends.
The invention also relates to a cam weave mechanism for
a loom that comprises a leveling device as described
hereinabove. Such a mechanism is more economical, more
reliable and easier to use, particularly for leveling
the frames of the loom, than the known items of
equipment.
Finally the invention relates to a loom fitted with a
weave mechanism as mentioned hereinabove. Such a loom
is easier to use than those of the prior art.
The invention will be better understood and other
advantages of the latter will appear more clearly in
the light of the following description of a loom and a
weave mechanism fitted with a leveling device according
to the invention, given solely as an example and made
with reference to the appended drawings in which:

- figure 1 is a partial schematic representation of the
principle of a loom according to the invention;
- figure 2 is a schematic representation on a larger
scale of the weave mechanism of the loom of figure 1
in the weaving configuration;
- figure 3 represents some parts of the mechanism of
figure 2 when the latter switch from a weaving
configuration to a leveling configuration;
- figure 4 is a view similar to figure 3, when the
mechanism is in the leveling configuration;
- figure 5 is a view on a larger scale of detail V in
figure 2;
- figure 6 is a view on a larger scale of detail VI in
figure 4 and
- figure 7 is a view in perspective of some elements
forming the leveling device of the mechanism
represented in figures 2 to 6.
The loom M shown in figure 1 comprises several heddle
frames only one of which is shown in figure 1 with
reference number 1. The various frames of the loom M
operate in a vertical oscillation movement shown by the
double arrow Fi and imparted by a cam mechanism 10 whose
output levers 11 act respectively on connecting rods 12
associated with bent levers 13 connected together and
to the frame 1 by connecting rods 14.
The levers 11 are provided in a number equivalent to
the number of heddle frames 1 and mounted so as to
pivot, as shown on the double arrow F2, about the
longitudinal axis of a common shaft 15 held by the
frame 16 of the mechanism 10. The shaft 15 is fitted,
at its two ends, with two eccentrics 17 and 17' that
themselves support the shaft 15 and that are supported
by two bearings, not shown, defined by the frame 16.
The mechanism 10 also comprises several matching cams
18 whose twin tracks 18A and 18B are pressed upon by
the rollers 19A and 19B of one and the same lever 11.

Thus, each lever 11 follows a movement imposed by the
geometry of the tracks 18A and 18B of the cam 18 with
which it is associated.
A ring and pinion assembly 20 is mounted at the end of
the shaft 21 common to the cams 18. For the clarity of
the drawing, the ring and pinion assembly 20 is shown
only in figures 1 and 2.
A cover 16B mounted on the frame 16 and represented by
its silhouette in dot-and-dash lines only in figures 1
and 2 makes it possible to isolate the elements 15 to
21 from the outside.
In figure 2, the track of the shaft 15 is shown in dot-
and-dash lines and its geometric axis is referenced X15.
In the same manner, one notes X17 the geometric pivoting
axis of the eccentrics 17 and 17' and X21 the geometric
axis of the shaft 21. These axes are globally parallel
with one another.
In the weaving configuration represented in figure 2,
in which the oscillating levers 11 are designed to
drive the heddle frames 1 and equivalents, the axes X15
and X17 and X21 are coplanar, which means that the
separating forces between the shafts 15 and 21
resulting from the action of the cams on the levers do
not tend to rotate the eccentric 17 and to load its
control device.
When the user requires to level the frames 1, he must
bring the levers 11 to the configuration of figure 4 in
which the rollers 19A and 19B are separated from the
cams 18 and in which the levers 11 all have the same
angular position relative to the axis X15.
To do this, an electric motor 40 is mounted on a
support 41 articulated about an axis X42 defined by two
bearings, only one of which is visible in figure 2 with

reference number 42, these bearings being supported by
a mid-part 16A of the frame 16. The axis X42 is globally
parallel with the axes X15, X17 and X21.
Thus, the assembly formed by the elements 40 and 41 may
pivot about the axis X42 as shown by the double arrow
F3.
The output shaft 40A of the motor 40 is received in a
sleeve 43 held, thanks to a bearing 44, in the support
41. A pin 45 makes it possible to combine the shaft 40A
and the sleeve 43 in rotation. Furthermore, a threaded
rod 46 is engaged in the sleeve 43 and fixedly attached
in rotation to the latter thanks to a cotter 47. Thus,
the threaded rod can be rotated by the motor 40 in a
direction that depends on the supply current of the
motor 40.
As a variant, the output shaft of the motor 40 could
protrude outside the support 41 and be threaded.
A nut 50, whose tapping is adapted to the thread of the
rod 46, is mounted on this rod and held captive at the
end of a maneuvering arm 60 fixedly attached to the
eccentric 17 and extending substantially in a radial
direction relative to the axis X17. The arm 60, which
makes it possible to exert a torque to rotate the
eccentric 17 about the axis X17, comprises a main part
60A and a plate 60B fitted to the part 60A. The nut 50
is held in a yoke between the elements 60A and 60B. It
is provided with two trunnions, only one of which is
visible with reference number 61, that are engaged in
the corresponding bores of the elements 60A and 60B, so
that the nut 50 is articulated relative to the arm 60
about an axis X61 substantially parallel with the axes
X15, X17, X21 and X42.
It should be noted that the plate 60B is not shown in
figures 2 to 6 for clarity of the drawing.

When it is necessary to move the various oscillating
levers 11 toward their leveling position, the motor 40
is actuated to drive the threaded rod 46 in a rotary
direction R causing the nut 50 to move in the direction
of the support 41, as shown by the arrow F4. The effect
of this movement is to rotate the arm 60 and the
eccentric 17 in the direction of the arrow F5, which has
the effect of rotating, in the same direction, the
geometric axis X15 about the geometric axis X17 thus
moving the shaft 15 away from the shaft 21 in a
trajectory in an arc of a circle C represented in dot-
and-dash lines in figure 3.
Passing through the intermediate position of figure 3,
it is therefore possible to reach the position of
figure 4 in which all the rollers 19A and 19B of the
levers 11 are disengaged from the cams 18, the levers
being in line, so that the frames 1 are also in line.
The fact that the assembly formed by the motor 40 and
the support 41 is mounted so as to oscillate about the
axis X42 makes it possible to achieve the various
orientations necessary for the threaded rod 46 during
the upward movement of the nut 40 along this rod and in
the direction of the support 41, these various
orientations originating from the variation in the
horizontal distance d between the central axis X46 of
the rod 46 and the axis X17.
A stop 70 is mounted on the frame 16 and supports a
contact switch 71 provided with a rod 72 against which
a surface 62 of the arm 60 presses, as shown in
figure 5. This makes it possible to detect that the
eccentrics 17 and 17' are really in an end-of-travel
position in which the rollers of the various levers 11
are in a position of reduced clearance with the twin
tracks of the associated cams 18. When the switch 71 is
actuated, the supply of the motor 40 is interrupted and

weaving can take place.
In addition, the arm 60 is extended by an extension 63
diametrically opposed to the end of the arm 60 on which
the nut 50 swivels and which presses against a surface
73 of the stop 70 in the configuration of figure 4.
According to a variant of the invention that is not
shown, a switch of the type of the switch 71 may be
provided on the stop 70 to detect the fact that the
weave mechanism is in the leveling configuration.
The invention is not limited to the single embodiment
described and may, in particular, be used with the
devices shown in figures 2 and 5 of EP-B-0 580 528.
According to a variant, not shown, of the invention,
the axis of articulation of the drive assembly may be
situated on the opposite side of the motor output shaft
relative to this motor, that is to say, in the
representation of the figures, above the motor.

CLAIMS
1. A device for leveling the position of the frames
of a loom fitted with a cam weave mechanism, said
frames being actuated by oscillating levers
provided with cam followers and mounted on a
common shaft whose position relative to the frame
of the mechanism can be varied by means of at
least one eccentric, characterized in that the
angular orientation of said eccentric (17, 17') is
controlled by means of a drive assembly (40, 41)
articulated (at 42) on said frame about an axis
(X42) globally parallel with the pivoting axis (X17)
of said eccentric, the output shaft (40A) of said
drive assembly being fixedly attached in rotation
with, or formed by, a threaded rod (46) engaged in
a captive nut (50) of a maneuvering arm (60) of
said eccentric (17).
2. The device as claimed in claim 1, characterized in
that said nut (50) is articulated relative to said
maneuvering arm (60) at least about an axis (X61)
globally parallel with said pivoting axis (X17) of
said eccentric (17, 17').
3. The device as claimed in one of the preceding
claims, characterized in that said maneuvering arm
(60) is provided with a surface (62) for pressing
against an end-of-travel stop (70) when said
eccentric (17, 17') is in a position (figures 2,
5) compatible with the use of the weave mechanism
(10) for weaving.
4. The device as claimed in one of the preceding
claims, characterized in that it comprises a
member (63) driven by said eccentric (17) and
capable of pressing against an end-of-travel stop

(73) when said levers (11) are in the leveling
position (figures 4 and 6).
5. The device as claimed in claim 4, characterized in
that said member (63) is fixedly attached to said
maneuvering arm (60).
6. The device as claimed in one of claims 3 to 5,
characterized in that said stop (70, 73) is fitted
with means (71) for detecting the pressure of said
arm (60) or of said member (63) in said position.
7. The device as claimed in one of the preceding
claims, characterized in that, in the
configuration for using the weave mechanism for
weaving (figures 2, 5), the geometric axis (X15) of
the shaft (15) common to said levers (11), the
geometric axis (X21) of the drive shaft (21) of
said cams (20) and the geometric pivoting axis
(X17) of said eccentric (17, 17') are substantially
parallel and coplanar.
8. The device as claimed in one of the preceding
claims, characterized in that said shaft (15)
common to said levers (11) is supported relative
to said frame (16) by means of two eccentrics (17,
17') each placed in the vicinity of one of its
ends.
9. A cam weave mechanism (10) for a loom,
characterized in that it comprises a leveling
device (40-72) as claimed in one of the preceding
claims.
10. A loom (M) fitted with a weave mechanism (10) as
claimed in claim 9.

The invention relates to a weaving machine which is fitted with a cam harness
mounting mechanism (10), wherein the frames are actuated by oscillating levers (11)
provided with cam followers (19A) and mounted on a common shaft (15) whereby the
position thereof can be varied in relation to the frame (16) with the aid of at least one
eccentric (17). The angular orientation of said eccentric (17) is controlled with the aid
of a motorization unit (40, 41) which is articulated (en 42) on the frame (16) about an
axis (X42) which is globally parallel to the pivoting axis (X17) of the eccentric 1 (17),
and the output shaft of the motorization unit (40, 41) is rotationally coupled to or
formed by, a threaded rod (46) which is engaged in a plate nut (50) of a maneuvering
arm (6) of the eccentric (17).

A DEVICE FOR LEVELLING THE POSITION OF THE FRAMES OF A LOOM FITTED WITH A CAM WEAVE MECHANISM

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