[0001] The present invention concerns a fast guide device for the control rods of heald
frames in a loom, and particularly a device of this type apt to keep in a correct
position the unused control rods, when the loom is working with a number of heald
frames below the maximum number thereof foreseen on the loom by the constructor.
[0002] As known, the heald frames are rectangular frames formed by a pair of horizontal
crosspieces and by two vertical sidepieces, into which is inserted a plurality of
vertical healds - thin metal bars with a central slot - apt to guide the reciprocating
motion of the warp yarns, each of which passes through the slot of a respective heald.
The reciprocating motion, verticalwise, of the heald frame causes the corresponding
motion of groups of warp yarns, hence determining the opening of the shed according
to a pattern prearranged by the weaver, to allow picking the wefts. The heald frames
vary in number - from a minimum of two to a maximum normally below twenty - according
to the special design one wishes to weave. It is thus evident that the loom constructor
sells its machines prearranged for working with a maximum number of heald frames;
it is then up to the weaver to keep on the loom, each time, only the number of frames
which will be required to weave a certain fabric.
[0003] The vertical shifting of the healds is obtained by special articulated systems which
- in a particularly successful and widespread construction - impart a reciprocating
motion, verticalwise, to a series of rods, commonly known as heald control rods, which
in turn transmit said motion to the heald frames. The device of the present invention
particularly applies to this type of driving mechanism of the heald frames which,
for further clearness, will now be described in detail with reference to figs. 1,
2 and 3, of which:
Fig. 1 is a diagrammatic front view of a heald frame and of the respective driving
mechanism;
Fig. 2 is a front sectional view, on an enlarged scale, of a control rod for heald
frames, showing also two possible cross sections of the rod; and
Fig. 3 is a front sectional view, on an enlarged scale, showing the detail wherein
the heald control rod is fixed to the heald frame.
[0004] Fig. 1 shows diagrammatically a single heald frame 1, which is caused to perform
a reciprocating motion verticalwise by the weave machine (not shown), through square
levers 2 controlling the motion of the heald control rods 3 (two rods for each heald
frame). To obtain the mechanical connection between the heald frame 1 and the heald
rods 3, said frame is provided, at its upper corners, with coupling tabs 4 apt to
engage, with a hook mouth thereof, onto a bush 5 screwed on the upper end of the rod
3 which is suitably threaded for the purpose. By changing the position of the bush
5 on the heald rod 3, it is possible to adjust the height of the frame 1 to the desired
extent, according to weaving requirements.
[0005] The steady correct vertical positioning of the heald control rods 3 and consequently
of the heald frames 1, and the correct spacing between them, is guaranteed by two
pairs of racks 6 - one pair on each side of the group of frames - each rack being
provided with a number of teeth equal to the maximum number of frames supplied on
the loom. Each rack tooth contributes to keep in a stable position - with the slack
required to allow its free axial movement - a heald control rod 3 against the bottom
of a longitudinal guide slot 8 provided on the sidepieces 7 of the frames 1, as clearly
shown in the section A-A of fig. 3. The racks 6 are in turn anchored onto lateral
supports 9 of the loom, which are normally fixed.
[0006] The lateral supports 9 may however oscillate outwardly of the loom, about hingeing
axes Z, so as to release the frames 1 from the racks 6 and from the heald control
rods 3, and thereby allow the necessary replacements or changes on such frames, when
breakages or modifications on the fabric being woven require these operations. To
obtain this result, it is however necessary to previously block the heald control
rods 3 to the supports 9, so that they may follow them in their oscillating movement,
thus releasing both the sidepieces 7 and the coupling tabs 4 of the frames 1. Said
result is normally obtained with a pair of templates 10, having a plurality of holes
11 equal in number to that of the rods 3, each template being temporarily fixed to
a respective lateral support 9 (fig. 3) so as to block in position the heald control
rods 3. This allows not only to block the rods 3 on the supports 9, but also to make
sure that said rods remain in the exact working position, so as to avoid any problems
or waste of time when the frames 1 have to be mounted again.
[0007] Nevertheless, the aforedescribed operation of mounting and removing the frames 1
can be carried out with the necessary precision and at the required speed only when
all the loom frames are working, which is indeed fairly rare. In fact, in the more
frequent cases in which the loom works only with part of the frames available, the
problem arises to block the heald control rods 3 which are not working, namely those
onto which no frames are mounted. Said rods in fact, due to their actual construction
and assembly, cannot be released, as they would end by dropping into the loom, thereby
causing damages to the warp yarns or hampering the regular operation of the working
frames. It is thus a common praxis to temporarily fix the rods 3 which are not working
to the supports 9, using the most different methods.
[0008] However, this solution has two kinds of drawbacks, the common consequence of which
is to slow down the operation of replacing the frames and thus prolong the non-working
period of the loom; this proves to be day after day more harmful from the economical
point of view, taking into account, on one hand, the high capital and running costs
and, on the other hand, the considerable productivity levels reached by modern looms.
[0009] A first drawback hence lies in the fact that the fixing has to be done by way of
tightening elements, blocked in position by clamps, pins, or other means, which anyhow
involve the use of appropriate tools. Such tightening elements are normally quite
numerous, as they must be changed according to the total number of inactive rods having
to be blocked in position. Often, moreover, said tightening elements are not permanently
set on the loom, or should anyhow be removed therefrom when wishing to use all the
heald frames. In other words, these are rudimentary systems, which involve the use
of a variety of elements, and of tools, as well as a considerable waste of time for
their setting up.
[0010] A second drawback lies instead in the fact that such tightening elements, presently
used in technique. are not apt to safely and positively keep the heald control rods
3 in their exact working position. Thus, when the weaver has to work on the frames
1 and should hence previously set on the templates 10, he meets with some difficulties
in introducing exactly into the holes 11 the rods 3 which were not already guided
by the frames 1, that is, the non-working rods 3. In fact, since their hingeing onto
the axis Z leaves a fair degree of freedom. not only in the plane shown in fig. 1
but also in a plane perpendicular thereto, it is almost inevitable that between one
weave and the next - due to the considerable loom vibrations - said rods move away
from their correct position and thus create problems when wishing to operate a quick
insertion thereof into the templates 10.
[0011] The object of the present invention is therefore to overcome the aforementioned drawbacks,
by supplying a fast guide device for the heald control rods, which is apt to operate
with the greatest simplicity and speed on all the rods 3 which are not working, independently
from their number, and to keep said rods perfectly in position during the whole weaving
operation, so as to create no problems when the operator has to set the templates
10 onto said rods 3.
[0012] According to the present invention, said object is reached by means of a loom comprising
a fast guide device for the control rods of heald frames, of the type in which one
end of said rods is hinged onto the same axis on which there are hinged lateral supports
to which said rods are fixed during certain weaving operations, characterized in that
it comprises at least one screw and nut element, whose pitch is equal to the distance
between the axes of said control rods, the nut being fixed to one of said lateral
supports and the screw being positioned with its axis parallel to the plane of said
rods and adjacent thereto, the thread of said screw consisting of a helical cavity
apt to engage with said rods so as to keep them in a stable position between said
screw and the respective lateral support.
[0013] The invention will now be described in further detail, with reference to a preferred
embodiment thereof, illustrated in figs. 4 and 5 of the accompanying drawings, of
which:
Fig. 4 is a side elevation view of the fast guide device according to the present
invention mounted inside a loom; and
Fig. 5 is a partial section view along the line C-C of fig. 4.
[0014] To show more clearly its positioning inside the loom - where it is indicated by the
letter D - the device of the present invention has also been diagrammatically illustrated
in dashed lines in the front view of fig. 1.
[0015] With reference to fig. 4, it should be noted first of all that the right side thereof
is that facing the loom reed, namely the weft picking side. The sheet on which said
figure is drawn represents one of the lateral loom supports 9, to which the racks
6 are anchored and to which is also fixed the device of the present invention. Said
device consists of a long screw 12 and of a respective nut 13, which is fixed to the
support 9 - with the interposition of a plate 14, fixed in respect of the nut 13 -
by means of locking nuts housed into slots 15. The thread of the screw 12 forms a
helical cavity, the section of which is apt to engage - with the required slack -
the section of the heald control rods 3. In the illustrated embodiment, said cavity
has a rectangular section, while the heald control rods 3 have a circular section;
other sections can however be provided - as shown for the heald control rods 3 in
fig. 2 (Sec. B-B) - without thereby departing from the scope of the present invention.
[0016] The thread pitch P of the screw 12 corresponds exactly to the distance between the
axes of adjacent heald control rods 3, so that, by positioning said screw next to
the row of rods 3, these house themselves tangentially inside the threading of the
screw 12 (see fig. 5). During initial setup of the device, the position of the screw
12 is axially modified by moving the plate 14 in respect of the support 9 thanks to
the slots 15. Once having determined the position wherein the engagement between the
screw 12 and the rods 3 takes place with the required precision, the plate 14 is locked
in said position and no longer removed. At this stage, by rotating the screw 12 in
respect of the nut 13, it is possible to engage with the screw 12 the selected number
of rods 3 - starting from the one furthest from the reed - up to reaching the rod
closest to the reed (right side of the drawing), hence providing to block in a steady
position the rods which are not working and leaving instead perfectly free the rods
which have to engage onto the corresponding heald frames.
[0017] It should in fact be remembered in this respect that, in the normal weaving technique,
the heald frames are operated starting from the ones closest to the reed, up to gradually
reaching the furthermost ones. The device of the present invention hence allows to
operate the frames just in this order, while simultaneously blocking in position the
heald control rods which are not working and thereby reaching, with the greatest simplicity
and efficiency, one of the objects of the present invention. The screw 12 is in fact
constantly operating on the loom and it requires no special tool for its forward or
backward rotation since, by means of a suitable handle 16 provided on its head, it
can be easily hand operated.
[0018] The aforedescribed guide device for control rods of heald frames allows to simultaneously
reach also the second object of the invention. In fact, as seen above, the axial displacements
performed by the screw 12 through rotation thereof - in order to vary the number of
heald control rods 3 blocked in position - take place without ever releasing the grip
on such rods, which hence keep their position permanently unaltered. Furthermore,
any heald control rods which must cease to work are, after removal of the respective
heald frame, immediately set in a correct position by simple forward rotation of the
screw 12. Thus, at any moment of the weaving operation, the heald control rods 3 are
in a perfectly and constantly centred position, whereby their insertion into the template
10 (which is anyhow always useful, as it provides to position and block the working
rods before removal of the heald frames, and thus before the screw 12 may block them
in position) is extremely easy, and could even be obtained automatically, seen that
a manual intervention - required up to date - is no longer needed to cause the exact
insertion of each of the non-working rods 3 into the corresponding hole 11 of the
template 10.
[0019] The working of the nut 13 has not been illustrated in detail, as it concerns a fully
known mechanical construction. Said nut can be of the thread type or of the pin type,
or even of other types, without altering the functionality of the fast guide device
of the invention. According to the invention, the nut 13 is simply required to guarantee
a total absence of axial slack of the screw 12 and, at the same time, to provide locking
means to stop the rotation of said screw and block it in the wanted position during
the loom working steps. It is not important for the screw 12 to be rigidly blocked
in position - since, as already said, the rotations thereof do not change the position
of the heald control rods - but it is sufficient for the locking means to prevent
a rotation of said screw which could lead its front end to interfere with the last
working frame.
[0020] Finally, to improve the engagement between the thread of the screw 12 and the heald
control rods 3, it is preferable to mount said screw on the support 9 inclined by
an angle α equal to the angle of the helical threading. In this way, in correspondence
of the rod engagement zone, the threading is parallel to said rods and the engagement
turns out to be smoother. Although preferred, said characteristic is however not binding.
In fact, by suitably varying the shape of the cavity forming the screw thread, it
is possible to obtain an efficient screw/rod engagement even with the screw 12 positioned
in different ways, other than that shown in figures 4 and 5.
1. Loom comprising a fast guide device for the control rods (3) of heald frames (1),
of the type in which one end of said rods (3) is hinged onto the same axis (Z) on
which there are hinged lateral supports (9) to which said rods (3) are fixed during
certain weaving operations, characterized in that it comprises at least one screw
(12) and nut (13) element, whose pitch (P) is equal to the distance between the axes
of said control rods (3), the nut (13) being fixed to one of said lateral supports
(9) and the screw (12) being positioned with its axis parallel to the plane of said
rods (3) and adjacent thereto. the thread of said screw consisting of a helical cavity
apt to engage with said rods (3) so as to keep them in a stable position between said
screw and the respective lateral support (9).
2. Loom comprising a guide device as in claim 1), wherein said nut (13) is fixed to the
lateral support (9) by fixing means (15) allowing to adjust the axial position of
said screw (12).
3. Loom comprising a guide device as in claim 1), wherein said nut (13) is of the type
with internal thread cooperating with the helical cavity of said screw (12).
4. Loom comprising a guide device as in claim 1), wherein said nut (13) is of the pin
type cooperating with the helical cavity of said screw (12).
5. Loom comprising a guide device as in claim 1), wherein said nut (13) comprises also
locking means to stop the rotation of said screw (12) in a desired position.
6. Loom comprising a guide device as in claim 1), wherein said control rods (3) of the
heald frames (1) have a circular or oval section. and the section of the helical cavity
of said screw (12) is square or rectangular.
7. Loom comprising a guide device as in claim 1), wherein the axis of said screw (12)
is inclined in respect of the horizontal plane of the loom by an angle (α) equal to
the inclination of the screw thread.
1. Webmaschine mit einer festen Führungsvorrichtung für die Steuerstangen (3) der Schäfte
(1) von der Art, bei der das eine Ende der Stangen (3) auf derselben Achse (Z) angelenkt
ist, auf der die lateralen Träger (9) angelenkt sind, an denen die Stangen (3) während
bestimmter Webvorgänge befestigt sind, dadurch gekennzeichnet, daß sie wenigstens
ein Element mit einer Schraube (12) und einer Mutter (13) aufweist, wobei die Steigung
(P) gleich dem Abstand zwischen den Achsen der Steuerstangen (3) ist, die Mutter (13)
an dem einen der lateralen Träger (9) befestigt ist und die Schraube (12) mit ihrer
Achse parallel zu der Ebene der Stangen (3) und diesen benachbart positioniert ist,
wobei das Gewinde der Schraube aus einer schraubenförmigen Ausnehmung besteht, die
dazu eingerichtet ist, die Stangen (3) derart zu ergreifen, daß diese in einer stabilen
Position zwischen der Schraube und dem jeweiligen lateralen Träger (9) verbleiben.
2. Webmaschine mit einer Führungsvorrichtung nach Anspruch 1, wobei die Mutter (13) einen
dem lateralen Träger (9) mittels Befestigungsmittel (15) befestigt ist, die es erlauben,
die axiale Position der Schrauben (12) einzustellen.
3. Webmaschine mit einer Führungsvorrichtung nach Anspruch 3, wobei die Mutter (13) von
der Art mit einem Innengewinde, das mit der schraubenförmigen Ausnehmung der Schraube
(12) zusammenwirkt, ist.
4. Webmaschine mit einer Führungsvorrichtung nach Anspruch 1, wobei die Mutter (13) vom
Stifttyp ist, die mit der schraubenförmigen Ausnehmung der Schraube (12) zusammenwirkt.
5. Webmaschine mit einer Führungsvorrichtung nach Anspruch 1, wobei die Mutter (13) weiter
Verriegelungsmittel zum Stoppen der Drehung der Schraube (12) in einer gewünschten
Position aufweist.
6. Webmaschine mit einer Führungsvorrichtung nach Anspruch 1, wobei die Steuerstangen
(3) die Schäfte (1) einem kreisförmigen oder ovalen Querschnitt haben und der Querschnitt
der schraubenförmigen Ausnehmung der Schraube (12) quadratisch oder rechteckig ist.
7. Webmaschine mit einer Führungsvorrichtung nach Anspruch 1, wobei die Achse der Schraube
(12) bezüglich der horizontalen Ebene der Webmaschine um einen Winkel a geneigt ist,
der der Neigung des Gewindes der Schraube entspricht.
1. Métier comprenant un dispositif de guidage fixe pour les tiges de commande (3) de
cadres à lisses (1) du type dans lequel une extrémité desdites tiges (3) est articulée
sur le même axe (Z) sur lequel sont articulés des supports latéraux (9) auxquels lesdites
tiges (3) sont fixées durant certaines opérations de tissage, caractérisé en ce qu'il
comprend au moins un élément à vis (12) et écrou (13), dont le pas (P) est égal à
la distance entre les axes desdites tiges de commande (3), l'écrou (13) étant fixé
à l'un desdits supports latéraux (9) et la vis (12) étant positionnée avec son axe
parallèle au plan desdites tiges (3) et adjacent à celui-ci, le filet de ladite vis
consistant en une cavité hélicoïdale adaptée à s'engager avec lesdites tiges (3) de
manière à les garder dans une position stable entre ladite vis et le support latéral
(9) respectif.
2. Métier comprenant un dispositif de guidage selon la revendication 1, dans lequel ledit
écrou (13) est fixé au support latéral (9) par un moyen de fixation (15) permettant
de régler la position axiale de ladite vis (12).
3. Métier comprenant un dispositif de guidage selon la revendication 1, dans lequel ledit
écrou (13) est du type avec un filet intérieur coopérant avec la cavité hélicoïdale
de ladite vis (12).
4. Métier comprenant un dispositif de guidage selon la revendication 1, dans lequel ledit
écrou (13) est du type tige coopérant avec la cavité hélicoïdale de ladite vis (12).
5. Métier comprenant un dispositif de guidage selon la revendication 1, dans lequel ledit
écrou (13) comprend également un moyen de blocage pour arrêter la rotation de ladite
vis (12) en une position souhaitée.
6. Métier comprenant un dispositif de guidage selon la revendication 1, dans lequel lesdites
tiges de commande (3) des cadres à lisses (1) ont une section circulaire ou ovale,
et la section de la cavité hélicoïdale de ladite vis (12) est carrée ou rectangulaire.
7. Métier comprenant un dispositif de guidage selon la revendication 1, dans lequel l'axe
de ladite vis (12) est incliné par rapport au plan horizontal du métier d'un angle
(α) égal à l'inclinaison du filet de vis.