DETAILED DESCRIPTION OF THE INVENTION
INDUSTRIAL FIELD OF UTILIZATION
[0001] The present invention relates to an apparatus for controlling fluid injection pressure
of an auxiliary nozzle in a jet loom and, more specifically, to the above apparatus
in a jet loom, having at least one weft detector, a plurality of the auxiliary nozzles,
a fluid supply reservoir from which fluid under pressure is supplied to the auxiliary
nozzles through lines each having an electromagnetically-operated valve, and a controller
for controlling the operation of the valve.
PRIOR ART
[0002] In a conventional jet loom having a weft feeler which is disposed at a predetermined
terminating extremity position of weft flying passage across the loom for monitoring
the weft arrival time, or the time at which the leading end of an inserted weft arrives
at a position defined by the weft feeler, the fluid pressure in a fluid supply reservoir
is so set that a specific kind of weft, which requires the longest time to fly to
the weft feeler, may arrive at the destination within a predetermined period time,
and the time at which a solenoid-operated stop pin in a drum type weft measuring device
is disengaged from the drum thereof for weft releasing, as well as the times at which
main and auxiliary nozzles are activated respectively for fluid injection are controlled
according the average arrival time of the leading end of the inserted wefts.
[0003] This method of controlling the fluid injection pressure of auxiliary nozzles tends
to waste fluid and it is practically impossible with this method to recover the flying
speed of such weft that has once decelerated or stalled on its way of flying through
a warp shed. An attempt to solve the above problems has been made by an apparatus
disclosed by Publication of unexamined Japanese patent application No. 62-257441 (1987).
This apparatus includes three separate reservoirs holding therein fluids under different
pressures and the reservoir from which its fluid is to be supplied to the respective
auxiliary nozzles is selectively changed as required in accordance with a signal transmitted
from a weft detector so that the weft speed is adjusted on its way of flying through
a shed. This conventional apparatus is disadvantageous, however, in that the provision
of plural fluid supply reservoirs and their associated conduit lines require additional
space for their installation and make the whole apparatus complicated.
PROBLEMS THAT THE INVENTION IS TO SOLVE
[0004] Therefore, it is an object of the present invention to provide an auxiliary nozzle
injection pressure controlling apparatus in a jet loom which can solve the above-identified
problems by saving the installation space, as well as fluid consumption of the auxiliary
nozzles.
MEANS SOLVING THE PROBLEMS
[0005] In order to solve the above problems, there is provided an apparatus for controlling
the fluid injection pressure of an auxiliary nozzle in a jet loom, having at least
one weft detector, a plurality of the auxiliary nozzles, a fluid supply reservoir
from which fluid under pressure is supplied to the auxiliary nozzles through lines
each having a first electromagnetically-operated valve, and a controller for controlling
the operation of the valves, the apparatus being characterized in that in that each
of the lines is provided with a bypass line having a second electromagnetically-operated
valve whose operation may be controlled by the controller for each weft insertion
according to the information of time at which each inserted weft has arrived at a
predetermined position along weft flying passage in a warp shed of the loom.
OPERATION OF THE INVENTION
[0006] In the above apparatus having a line which bypasses the main line connected between
the fluid supply reservoir and the auxiliary nozzles and has therein a valve whose
operation is controlled by the controller according to the information of weft arrival
times from the weft detectors, the valve in the bypass line is caused to open thereby
to activate its associated auxiliary nozzle in response to a Signal from any weft
detector then detecting a delay in the weft arrival time at a position upstream of
the above auxiliary nozzle. Consequently, air under pressure through the bypass line,
as well as air through the main line, is supplied to the auxiliary nozzle, with the
result that the weft is accelerated so that it can arrive in a predetermined time
at a weft feeler disposed at a terminating extremity position of weft flying passage
across the loom. Because the apparatus of the invention requires only a single fluid
supply reservoir, space for installation of the reservoir can be saved and the apparatus
itself constructed simple. Additionally, each main line may be provided with a plurality
of bypass lines through which air streams of different flow rates are flown for effecting
two-step acceleration. Alternatively, in such arrangement of plural bypass lines,
air through one bypass line is used for the acceleration, while the other bypass line
may be arranged so as to supply air under a lower pressure and used in conjunction
with the main line for inserting different kinds of weft alternately.
EMBODIMENTS
[0007] The following will describe an embodiment of the apparatus for controlling the fluid
injection pressure of an auxiliary nozzle in a jet loom, while having reference to
the accompanying drawings. Figs. 1 through 4 show embodiments of the present invention
and details thereof:
- FIG. 1
- is an illustrative schematic view showing an embodiment of an apparatus for controlling
fluid injection pressure of an auxiliary nozzle in a jet loom according to the present
invention;
- FIG. 2
- is a diagram showing air injection timing of the auxiliary nozzles of the respective
groups;
- FIG. 3
- is an enlarged schematic view showing another embodiment of the apparatus according
to the invention; and
- FIG. 4
- is an enlarged schematic view showing still another embodiment of the apparatus according
to the invention.
[0008] Referring to FIG. 1, there is shown a main nozzle 1 of the loom for inserting a weft
Y into a warp shed by an air jet issued therefrom. The inserted weft Y is assisted
in flying through the shed by air jets injected from groups of auxiliary nozzles 2-6
to accelerate the weft so that the leading end thereof reaches a weft feeler 7 which
is located at a predetermined terminating extremity position of weft flying passage
beyond the shed across the loom for monitoring the time at which the leading end arrives
at that position defined by the weft feeler. Each of the auxiliary nozzle groups 2-6
comprises five nozzles 2a, 2b, 2c, 2d, 2e; 3a-3e; 4a-4e; 5a-5e. Five auxiliary nozzles
of each group are connected to a common air distributor 8, 9, 10, 11 or 12, so that
the five auxiliary nozzles of each group inject air under the same pressure.
[0009] There is provided an elongated hollow air reservoir 13 located across the loom and
holding therein compressed air. The air reservoir 13 has an inlet connected to any
suitable air source 15 through a regulator 14 for adjusting the air pressure in the
reservoir and outlets connected to the distributors 8-12 of the respective groups
of auxiliary nozzles 2-6 through conduit lines 16-20 having fixed throttle valves
21-25 for restricting the flow of air therethrough to the auxiliary nozzles so as
to adjust the air injection pressure of the nozzles with respect the air pressure
in the reservoir 13. The lines 16-20 include solenoid-operated valves 27-31 and the
time at which the solenoids are energized to open their associated valves of each
group is controlled by a controller 26.
[0010] The apparatus includes five weft detectors 32-36 disposed in a warp shed for detecting
the time at which the leading end of an inserted weft just arrives at each of such
weft detectors and connected to the controller 26 for transmitting thereto signals
which are representative of the arrival times of the leading end at the respective
weft detectors. As shown in FIG. 1, the controller 26 is connected also to the weft
feeler 7 for receiving therefrom a signal representative of the time at which the
leading end of an inserted weft arrives at that weft feeler. The controller 26 is
adapted to receive other signals indicative of other information necessary for controlling
weft insertion, e.g. air pressure in the reservoir 13 which is detected by a pressure
sensor 37 connected to the reservoir.
[0011] The apparatus according to the invention further includes bypass lines 42-46 connected
to bypass the throttle valves 21-25 and the solenoid-operated valves 27-31 in the
main lines 16-20. The bypass lines 42-46 have second solenoid-operated valves 3741
whose operation is controlled by the controller 26. Unlike the main lines 16-20, the
bypass lines 42-46 have no throttle, thus allowing more air to flow therethrough than
through the main lines to the distributors 8-12. In other words, flowing air through
the bypass lines 42-46 produces air jets under a higher pressure from the auxiliary
nozzles than flowing air through the main lines 16-20 having the air flow restricting
throttles 21-25, thus making possible acceleration of a weft flying in a shed.
[0012] In operation, when the weft detector 32 or 33 detects the leading end of an inserted
weft at a time which is later than required by any predetermined reference time, the
controller 26 then responding to a signal from that weft detector commands the solenoid
for the valve 39 to be energized so that the valve in the bypass line 44 for the group
of auxiliary nozzles 4a, 4b, 4c, 4d, 4e is opened. Accordingly, air under the same
pressure as the air in the reservoir 13 is allowed through the bypass line 44 and
meets at the distributor 29 with air flown through the main line 18 to be supplied
together therewith to the auxiliary nozzles 4a, 4b, 4c, 4d, 4e. Thus, air under a
pressure which is higher than that of air flowing only through the valve 29 in the
main line IS can be injected from the auxiliary nozzles 4, as indicated by the timing
diagram shown in FIG. 2, thereby accelerating the flying speed of the inserted weft
so as to recover the delay. If the weft detector 34 or 35 detects a delay in the weft
arrival time at the detecting point 34 or 35, the controller 26 causes the solenoid-operated
valve 41 in the bypass line 46 to for the group of auxiliary nozzles 6 to be opened.
Accordingly, two air flows through the main and bypass lines 20, 46 meet at the distributor
12, from where the combined air flow is supplied to the auxiliary nozzles 6a, 6b,
6c, 6d, 6e of the group 6. Thus, air under a higher pressure can be injected from
the auxiliary nozzles and the flying speed of the inserted weft can be accelerated
by air jets from the auxiliary nozzle group 5, as indicated in the diagram of FIG.
2.
[0013] Thus, in the event that the flying speed of an inserted weft is slowed down on its
way through a shed, any appropriate valve of the solenoid-operated valves 37-41 in
the bypass lines 42-46 is caused to open so that air flowing through the bypass line
meets at the distributor with air flowing through the main line, thereby increasing
air injection pressure of the auxiliary nozzles of a group located just downstream
of the position where the slowdown of weft flying speed has been detected. The result
is that the weft flying speed is accelerated by such increased air injection pressure
of the auxiliary nozzles. Alternatively, an increase of the air injection pressure
of the auxiliary nozzles for the acceleration may be effected by allowing air to flow
only through the bypass line with the main lines closed.
[0014] A modified embodiment of the invention is illustrated in FIG. 3, wherein the bypass
line, e.g. 42, has an adjustable throttle valve 47 to make possible adjustment of
the acceleration which may be required when any different kind of weft is to be handled.
[0015] FIG. 4 shows a further modified embodiment of the invention which differs from that
shown in FIG. 3 in that a second bypass line 48 is added. In this embodiment, at least
one of the bypass lines 42, 48 has an adjustable throttle valve 47 or 50 which may
be adjusted to allow less air flow therethrough than the fixed throttle valve 21 in
the main line 16. By so arranging, the bypass line having the adjustable throttle
valve may be used for decelerating the weft flying speed with the solenoid-operated
valve 27 in the main line 16 then closed. The other bypass line is used for the acceleration
as described in the above. Alternatively, in the arrangement of FIG. 4, the throttle
valve 50 may have very little restriction of air flow while the throttle valve 47
slight restriction so that two-step acceleration can be effected by firstly opening
the valve 37 and then activating the valve 49 with the former valve 37 closed. It
would be understood readily by those skilled in the art that this embodiment of FIG.
4 is applicable to alternate insertion of two different kinds of weft. That is, air
through the bypass line 48 is used for the acceleration and the valves 27 and 37 are
opened alternately to supply air under different pressures for inserting different
kinds of weft accordingly.
[0016] As it is apparent from the foregoing description of the embodiments according to
the invention, provision of a line bypassing the main line between the air supply
reservoir and the air distributor and having therein a controlled valve can dispense
with a plurality of air reservoirs holding air under different pressures. Therefore,
the construction of the apparatus can be simplified and requires smaller space for
the installation. Additionally, the apparatus of the invention is applicable to insertion
of different kinds of weft.
[0017] It is to be understood by those skilled in the art that the present invention is
not limited to the above-described embodiments but it may be practiced in other various
changes and modifications. For example, the weft detectors 32-36 provided in a warp
shed may be substituted for other means adapted to detect the leading end of an inserted
weft, e.g. a combination of a balloon sensor which is located adjacent a drum type
weft measuring device disposed upstream of the main weft inserting nozzle for detecting
the balloon in weft releasing from the device and a device which is adapted to figure
out the current position of the inserted weft leading end on the basis of weft release
signals provided by the balloon sensor.
[0018] To provide an apparatus for controlling fluid injection pressure of an auxiliary
nozzle 2a-2e, 3a-3e, 4a-4e. 5a-5e, 6a-6e in a jet loom, which is simple in construction
requiring only a small space for installation and saves fluid consumption. The apparatus
is adapted for use in a jet loom and has at least one weft detector 32-36, a plurality
of auxiliary nozzles 2a-2e, 3a-3e, 4a-4e. 5a-5e, 6a-6e, a fluid supply reservoir 13
from which fluid under pressure is supplied to each of the auxiliary nozzles 2a-2e,
3a-3e, 4a-4e. 5a-5e, 6a-6e through conduit lines 16-20 each having a first electromagnetically-operated
valves 27-31, and a controller 26 for controlling the operation of the valves 27-31,
wherein the apparatus includes a second electromagnetically-operated valve 37-41 provided
in a bypass line 42-46 bypassing the main line and the operation of the second valve
37-41 is controlled by the controller 26 according to the information of time at which
the leading end of each inserted weft Y has arrived at a predetermined position along
weft flying passage in a warp shed of the loom.
EFFECT OF THE INVENTION
[0020] Apparatus for controlling fluid injection pressure of an auxiliary nozzle in a jet
loom according to the invention can be constructed simple and is advantageous in space
factor by provision of a line bypassing the main line connected between the air supply
reservoir and an auxiliary nozzle, and having therein an electromagnetically-controlled
valve whose operation may be controlled by a controller for each weft insertion.
DESIGNATION OF REFERENCE NUMERALS
[0021] 1 .... Main nozzle,
2, 3, 4, 5, 6 .... Auxiliary nozzle groups,
7 .... Weft feeler,
8, 9, 10, 11, 12 .... Air distributors,
13 .... Air supply reservoir,
14 .... Air regulator,
15 .... Air source,
16, 17, 18, 19, 20 .... Main lines,
21, 22, 23, 24, 25.... Throttle valves,
26 .... Controller,
27, 28, 29, 30, 31... Solenoid-operated valves,
32, 33, 34, 35, 36... Weft detectors,
37, 38, 39, 40, 41..... Solenoid-operated valves
42, 43, 44, 45, 46... Bypass lines,
47, 50 .... Adjustable throttle valves,
48 .... Second bypass line,
49 .... Solenoid-operated valve.
1. An apparatus for controlling the fluid injection pressure of an auxiliary nozzle (2a-2e,
3a-3e, 4a-4e. 5a-5e, 6a-6e) in a jet loom, comprising at least one weft detector (32,
33, 34, 35, 36), a plurality of the auxiliary nozzles (2a-2e, 3a-3e, 4a-4e. 5a-5e,
6a-6e), a fluid supply reservoir (13) from which fluid under pressure is supplied
to said auxiliary nozzles (2a-2e, 3a-3e, 4a-4e. 5a-5e, 6a-6e) through lines (16, 17,
18, 19, 20) each having a first electromagnetically-operated valve (27, 28, 29, 30,
31), and a controller (26) for controlling the operation of said valves (27, 28, 29,
30, 31), said apparatus being characterized in that each of said lines (16, 17, 18,
19, 20) is provided with a bypass line (42, 43, 44, 45, 46) having a second electromagnetically-operated
valve (37, 38, 39, 40, 41) whose operation may be controlled by said controller (26)
for each weft insertion according to the information of time at which each inserted
weft (Y) has arrived at a predetermined position along weft flying passage in a warp
shed of the loom.
2. An apparatus for controlling the fluid injection pressure of an auxiliary nozzle (2a-2e,
3a-3e, 4a-4e. 5a-5e, 6a-6e) in a jet loom, comprising at least one weft detector (32,
33, 34, 35, 36) which is placed along the weft flying passage in a warp shed of the
loom, a plurality of auxiliary nozzles (2a-2e, 3a-3e, 4a-4e. 5a-5e, 6a-6e), a fluid
supply reservoir (13) from which fluid under pressure is supplied to said auxiliary
nozzles (2a-2e, 3a-3e, 4a-4e. 5a-5e, 6a-6e) through lines (16, 17, 18, 19, 20) each
having a first electromagnetically-operated valve (27, 28, 29, 30, 31), and a controller
(26) for controlling the operation of said valves (27, 28, 29, 30, 31), said apparatus
being characterized in that at least one of said lines (16, 17, 18, 19, 20) is provided
with a bypass line (42, 43, 44, 45, 46) leading to at least one auxiliary nozzle (2a-2e,
3a-3e, 4a-4e. 5a-5e, 6a-6e ) and having a second electromagnetically-operated valve
(37, 38, 39, 40, 41) whose operation is controlled by said controller (26) for each
weft insertion according to the information of time at which each inserted weft (Y)
has arrived at a predetermined position of a weft detector (32, 33, 34, 35, 36) which
is placed along the weft flying passage in the warp shed of the loom.
3. An apparatus as claimed in claim 1 or 2, with a plurality of weft detectors (32-36)
being places along the weft flying passage in the warp shed of the loom and/or a plurality
of bypasses (42-46) connecting the fluid reservoir (13) with individual auxiliary
nozzles (2a-2e, 3a-3e, 4a-4e. 5a-5e, 6a-6e) or groups of auxiliary nozzles (2a-2e,
3a-3e, 4a-4e. 5a-5e, 6a-6e).
4. An apparatus as claimed in any of claims 1 to 3, with a plurality of bypasses (42-46)
connected to one auxiliary nozzle (2a-2e, 3a-3e, 4a-4e. 5a-5e, 6a-6e) or a group of
auxiliary nozzles (2a-2e, 3a-3e, 4a-4e. 5a-5e, 6a-6e).
5. An apparatus as claimed in any of claims 1 to 4, where each bypass (42-46) is bypassing
at least one throttle valve (21-25) of a fluid conduit line (16-20).
6. An apparatus as claimed in any of claims 1 to 5, where fluid conduit lines (16-20)
and bypasses (42-46), as well as a group of auxiliary nozzles are connected to at
least one fluid distributor (8-12)
7. Apparatus as claimed in any of claim 1 to 6, for an air jet loom with auxiliary air
jet nozzles.
8. Fluid jet loom with an apparatus as claimed in any of claims 1 to 7.
9. Air jet loom with an apparatus as claimed in any of claims 1 to 7.