JP4658251B2 - Weft insertion device in water jet loom - Google Patents

Description

  The present invention relates to a weft insertion device in a water jet loom that injects water supplied from a weft insertion pump from a weft insertion nozzle to insert weft.

  In the water jet loom, a pump composed of a plunger, a cylinder, a lever system, etc., a cam mechanism for driving the pump, a pressurizing coil spring, a pipe, and a weft inserting device composed of a weft inserting nozzle are widely used. The operation of the weft insertion device is that a fixed amount of water is sucked and pressurized every weft insertion by a plunger pump equipped with check valves before and after the cylinder chamber and injected from the weft insertion nozzle. The weft is inserted into the warp opening by water injection from the nozzle.

  In the water jet loom, the water jet speed Vj, water jet cross-sectional area Aj, and water jet length L are adjusted according to the weaving conditions (specifically, the loom speed, yarn type, and weaving width). There is a need to. In the plunger-type pump, these three characteristic values Vj, Aj, and L are determined by the plunger thrust F, the plunger cross-sectional area Ap, the plunger stroke s, and the passage cross-sectional area An at the injection port of the weft insertion nozzle. If the water jet is regarded as a water column, the loss in the pipe line and the weft insertion nozzle is ignored, and the plunger thrust F is assumed to be a constant value, the following relationship exists between the characteristic values Vj, Aj, and L.

[Equation 1]
Vj = [2 × g × F / (Ap × γ)] ^1/2 (1)
Aj = An (2)
L = s × Ap / An (3)
Here, g is the acceleration of gravity, and γ is the specific weight of water.

  When changing from the weaving of a thin fabric such as taffeta to the weaving of a thick fabric such as an airbag, the thickness of the yarn becomes about 10 times thicker. In the case of such a thick yarn, since it is necessary to wrap the yarn around the yarn with a powerful jet, the weft insertion nozzle having a large diameter that can obtain a thick and powerful water jet is selected. (A weft insertion nozzle having a large cross-sectional area An is selected). If it is replaced with a weft insertion nozzle having a large diameter, if the plunger cross-sectional area Ap remains as it is, the jet length L will be insufficient according to equation (3), so that the plunger stroke s passes through the weft insertion nozzle to compensate for this. It is necessary to increase in proportion to the cross-sectional area An. Since the increase in the plunger stroke s has a mechanical limit, when the amount of water is larger than the limit value, the pump is changed to a pump having a large plunger sectional area Ap. In order to maintain the velocity Vj of the water jet, it is necessary to increase the plunger thrust F (increase the injection pressure at the weft insertion nozzle) by the equation (1), and if the compression amount of the coil spring is increased or still insufficient It can be replaced with a coil spring with a large spring constant.

In the multicolor weft insertion device of Patent Document 1, a throttle valve is installed near the weft insertion nozzle in the pipe line between the weft insertion nozzle and the pump, and the variable throttle is placed on the bypass pipe branched from the upstream side of this throttle valve. A bypass arrangement with a valve is disclosed. A part of the high-pressure water discharged from the pump is returned to the water tank via the bypass line and the variable throttle valve. In Patent Document 1, the purpose is to adjust the injection pressure in the weft insertion nozzle by opening the variable throttle valve.
No. 1-24152

In Patent Document 1, the bypass pipeline is directly connected to the water tank. Such a configuration brings about the following problems.
In the pump, at the moment when the cam lever constituting the cam mechanism is released from the cam restraint, the thrust of the coil spring directly acts on the plunger, and the water pressure in the cylinder rapidly increases corresponding to the sudden increase in thrust. At this time, a transient pressure wave is transmitted through the pipeline at the speed of sound. In the bypass configuration disclosed in Patent Document 1, the pressure wave is divided into a direction toward the weft insertion nozzle and a direction toward the variable throttle valve at the branching portion, and the pressure toward the variable throttle valve is determined by the variable throttle valve. Pass through to the water tank. A reflected wave is generated when the pressure wave toward the weft insertion nozzle reaches the outlet end, and a reflected wave is generated when the pressure wave toward the variable throttle valve reaches the outlet end. These reflected waves flow back through the pipeline and return to the pump, and are further reflected. The pressure waves generated in this way are superimposed, causing pulsation of the injection pressure.

  In the apparatus of Patent Document 1, the outlet portion of the variable throttle valve is located above the water tank, and the pressure of the outlet portion of the variable throttle valve is equal to or lower than the atmospheric pressure during a period in which water is not injected from the weft insertion nozzle. (Negative pressure). Therefore, when the loom is stopped for a long time, the water in the pipeline falls and the inside of the pipeline is filled with air. When operating the loom, it is necessary to operate the foot pedal to activate the pump and fill the pipeline with water. In the pipe on the weft insertion nozzle side, air can be easily released by several water injections, but in the bypass pipe on the variable throttle valve side, air tends to stay above the bypass pipe due to the influence of buoyancy. The air on the bypass line side is not quickly discharged to the water tank side. When the loom starts operating from the state where air remains in the bypass pipe, the remaining air is swept away over time, but the pulsation waveform of the injection pressure changes sequentially according to the amount of remaining bubbles. Eventually, a stable state is reached. However, in the process, the jet of water jet becomes unstable and a weft insertion failure tends to occur.

  Even if steady operation is reached, the problem of bubbles is not solved. Air is somewhat dissolved in the water, and local negative pressure is generated at the outlet of the variable restrictor. Therefore, the air dissolved in the water is aerated (aeration) or water is evaporated (cavitation) ) Is inevitable. If the downstream side of the variable throttle valve is below atmospheric pressure (negative pressure), the generated bubbles are not immediately dissolved in water but are finely dispersed and mixed in the pipeline. Even if the amount of bubbles mixed is small (for example, 1%), the bulk modulus of elasticity as a fluid is greatly reduced due to the compressibility of the bubbles, and the propagation speed of the pressure wave is also greatly reduced. The decrease in the propagation speed of the pressure wave delays the generation of the reflected wave and increases the pulsation cycle. An increase in the periodic pulsation reduces the rising response of the pressure waveform, resulting in poor weft insertion.

As described above, in the device disclosed in Patent Document 1, it is unavoidable that the pressure waveform is disturbed immediately after the start of injection, and the pulsation phenomenon is increased during the water injection period, which are undesirable for the weft insertion device.
An object of this invention is to provide the weft insertion apparatus in the water jet loom which can suppress the deterioration of the waveform of injection pressure.

The present invention is directed to a weft insertion device in a water jet loom that injects water supplied from a weft insertion pump from a weft insertion nozzle and inserts the weft yarn. The invention of claim 1 is directed to the weft insertion pump from the weft insertion pump. A diversion means capable of diverting a part of water from a water supply path to the inlet nozzle, the diversion means, a branch water path branched from the water supply path, and a bypass nozzle connected to an end of the branch water path the provided, and the injection port to the bypass nozzle, and a water discharge passage in communication with the atmospheric pressure region through the vent portion is formed while connected to the injection port, formed at a position different from the ventilation unit the outlet of the water discharge passage which is terminally connected hose is guided into the water tank, the water ejected from the bypass nozzle is injected toward the water discharge passage in communication with the atmospheric pressure region It said injected into the water discharge passage water characterized that you refluxed to the water tank through the hose from the outlet.

  In the configuration in which the water jetted from the bypass nozzle is jetted toward the atmospheric pressure region, the outlet portion of the bypass nozzle never falls below atmospheric pressure (negative pressure), so the pressure waveform caused by bubbles in the pipe line Deterioration is avoided.

In a preferred example, the shunt means, prior SL and waterways length leading to the weft insertion nozzle from the branch portion between the water supply path and said branch water passage, and waterways length are aligned leading to the bypass nozzle from said branch portion .

  As the difference between the length of the water channel from the branch portion to the weft insertion nozzle and the length of the water channel from the branch portion to the bypass nozzle becomes smaller, the deterioration of the pressure waveform of the water jet is suppressed. A configuration in which the water channel length from the branch portion to the weft insertion nozzle is the same as the water channel length from the branch portion to the bypass nozzle is particularly preferable for suppressing deterioration of the pressure waveform of water injection. The condition where the channel length from the branching section to the weft insertion nozzle is aligned with the length of the channel from the branching section to the bypass nozzle, the difference in these channel lengths is within the range where deterioration of the water jet pressure waveform is allowed. Including cases.

In a preferred example, a water drop prevention means for preventing water drop from the weft insertion nozzle and the bypass nozzle is provided.
If water drops from the weft insertion nozzle or the bypass nozzle while the loom is stopped, air is mixed into the pipe and the waveform of the injection pressure is deteriorated. The configuration that prevents water from dropping from the weft insertion nozzle and the bypass nozzle prevents air from entering the pipe.

  In a preferred example, the water drop prevention means is arranged so that the height position of the injection port of the weft insertion nozzle and the height position of the injection port of the bypass nozzle do not cause water drop. It is the structure which has arrange | positioned the injection port of a nozzle and the injection port of the said bypass nozzle.

  If there is a large difference in the height position between the injection port of the weft insertion nozzle and the injection port of the bypass nozzle, water drops due to the difference in water level between the two, and air bubbles are mixed into the pipeline, resulting in a poor injection pressure waveform. If there is no significant difference in height position between the weft insertion nozzle outlet and the bypass nozzle outlet, no water drop occurs due to the surface tension of the water.

In a preferred example, the water drop prevention means is configured such that the injection port of the weft insertion nozzle and the injection port of the bypass nozzle are arranged at the same height position.
The configuration in which the injection port of the weft insertion nozzle and the injection port of the bypass nozzle are arranged at the same height position is particularly effective in avoiding the suction of air from the injection port of the weft insertion nozzle or the injection port of the bypass nozzle. .

The good suitable examples, the cross-sectional area passes through the injection port of the weft insertion nozzle can be changed, the cross-sectional area passes through the injection port of the bypass nozzle can be changed.

  The combination of the weft insertion nozzle capable of changing the passage cross-sectional area and the bypass nozzle capable of changing the passage cross-sectional area facilitates appropriate adjustment of the amount of jet water in the weft insertion nozzle corresponding to the change in the weaving conditions. For example, if the weft yarn thickness is increased without changing the loom rotation speed and weaving width, the cross-sectional area of the weft insertion nozzle is increased to increase the thickness of the water jet, and the weft injection nozzle injection What is necessary is just to reduce the passage cross-sectional area in the injection port of a bypass nozzle according to the part which enlarged the passage cross-sectional area in an opening | mouth. That is, the sum of the passage cross-sectional area at the injection port of the weft insertion nozzle and the passage cross-sectional area at the injection port of the bypass nozzle may be adjusted to be a constant value. Also, for example, when the weaving width is increased without changing the thickness of the weft and the loom rotation speed, the passage cross-sectional area at the injection port of the weft insertion nozzle is not changed, and the passage cross-sectional area at the injection port of the bypass nozzle is not changed. It is sufficient to adjust so as to reduce the size. As a result, the amount of water sent to the weft insertion nozzle is increased as the weaving width increases.

  In a preferred example, a passage cross-sectional area at the injection port of the weft insertion nozzle is changed by a first electric drive means, and a passage cross-sectional area at the injection port of the bypass nozzle is changed by a second electric drive means. Is done.

The configuration in which the passage cross-sectional area at the injection port of the weft insertion nozzle and the passage cross-sectional area at the injection port of the bypass nozzle are changed by the electric drive means is advantageous for automation of the weft insertion device.
Variable range of the cross-sectional area passage in the injection port of the weft insertion nozzle is preferably in the range from 1.2 mm ² to 5 mm ^2.

Variable range of the cross-sectional area passage in the injection port of the bypass nozzle is preferably in the range of 0 mm ² to 5 mm ^2.
In a preferred example, a fluid spring means using a pressure of a compressible gaseous fluid as a spring force is used as a water injection pressure generating drive source in the weft insertion pump.

  The injection pressure at the weft insertion nozzle is determined by the thrust F acting on the plunger and the pressure (F / Ap) determined by the plunger cross-sectional area Ap, and the frictional resistance of the pipe wall on the way and the flow at the throttle valve connected in series with the weft insertion nozzle. It is a value obtained by subtracting the pressure drop due to the loss and the pressure drop due to the inertial effect of water. The increase in flow velocity resulting from the diversion increases the amount of pressure drop, which affects the water jet pressure. The apparatus disclosed in Patent Document 1 adopts a configuration in which the flow loss reaching the weft insertion nozzle is changed by adjusting a throttle valve provided in series with the weft insertion nozzle, thereby adjusting the water injection pressure at the weft insertion nozzle. It seems to be doing. However, in principle, it is unavoidable that the water injection flow rate and the water injection pressure at the weft insertion nozzle change in conjunction with each other due to the throttle operation of the variable throttle valve. That is, in the device disclosed in Patent Document 1, the variable throttle valve has a function of reducing the flow rate of water sent to the weft insertion nozzle by diverting the flow, but does not have a function of positively adjusting the water injection pressure.

  The configuration using the fluid spring means as the drive source for generating the water injection pressure in the weft insertion pump can adjust the water injection pressure in the weft insertion nozzle by adjusting the pressure of the compressible gaseous fluid. Easy.

  The present invention has an excellent effect that the deterioration of the pressure waveform of water injection in the water jet loom can be suppressed.

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
FIGS. 1A and 4A show a weft insertion device in a water jet loom, and FIG. 4B shows an internal structure of a weft insertion pump 11 constituting the weft insertion device.

  As shown in FIG. 4B, a water storage chamber forming cylinder 13 is integrally formed in the pump housing 12 constituting the weft insertion pump 11, and a plunger 14 is slidably received in the water storage chamber forming cylinder 13. Has been.

  A suction port 121 and a discharge port 122 are formed in the pump housing 12, and a water storage chamber 123 is formed between the suction port 121 and the discharge port 122. Check valves 15 and 16 are interposed between the water storage chamber 123 and the suction port 121 and between the water storage chamber 123 and the discharge port 122. As shown in FIG. 1A, the suction pipe 17 connected to the suction port 121 leads to the water tank 18, and the discharge pipe 19 connected to the discharge port 122 is connected to the weft insertion nozzle 20. Yes. The discharge pipe 19 is a water supply path for supplying water pumped from the weft insertion pump 11 to the weft insertion nozzle 20.

  A bellows 22 is attached to the base 21. A displacement transmission body 23 is fixed to the bellows 22, and a rotor 25 is rotatably attached to a joint 24 connected to the plunger 14. The displacement transmission body 23 and the rotor 25 are in contact with each other, and the pressure in the pressure chamber 221 (shown in FIG. 4A) in the bellows 22 is applied to the plunger 14 via the displacement transmission body 23, the rotor 25 and the joint 24. Is transmitted to. The bellows 22 and the pressure chamber 221 constitute fluid spring means (a drive source for generating water injection pressure in the weft insertion pump 11) using the pressure of a compressible gaseous fluid (air) as a spring force.

  The plunger 14 is connected to a cam lever 26 via a joint 24. The cam lever 26 can contact and separate from the cam 27 via the cam follower 261. The cam lever 26 is reciprocally oscillated by the cooperation of the cam 27 and the pressure in the bellows 22 that rotate in the direction of arrow Z in FIGS. 1A and 4A at a constant angular velocity in synchronization with the rotation of the loom. Is done. The plunger 14 reciprocates integrally as the cam lever 26 reciprocates.

  When the cam lever 26 rotates left about the support shaft 262, the plunger 14 moves in the forward movement direction indicated by the arrow Q in FIG. When the plunger 14 moves in the forward movement direction indicated by the arrow Q, the volume of the water storage chamber 123 increases and the water in the water tank 18 is sucked into the water storage chamber 123. When the plunger 14 moves in the forward movement direction indicated by the arrow Q, the volume of the pressure chamber 221 decreases and the pressure in the pressure chamber 221 starts to increase. Thereafter, the pressure in the pressure chamber 221 rises as the plunger 14 moves forward, and the pressure in the pressure chamber 221 becomes maximum when the plunger 14 finishes moving forward. While the check valve 15 is opened and absorbed in the water storage chamber 123, the check valve 16 is closed, and the water in the discharge pipe 19 does not flow back to the water storage chamber 123 side.

  When the cam follower 261 passes through the maximum diameter position Ma of the cam surface 271 of the cam 27, the cam lever 26 rotates to the right about the support shaft 262, and the plunger 14 is driven by the pressure of the air in the pressure chamber 221 as shown in FIG. It moves in the backward movement direction indicated by arrow R. When the plunger 14 moves in the backward movement direction indicated by the arrow R, the water in the water storage chamber 123 is pressurized. The pressurized water in the water storage chamber 123 is pumped to the weft insertion nozzle 20. The water pumped to the weft insertion nozzle 20 is jetted from the weft insertion nozzle 20, and the weft Y [shown in FIG. 1 (b)] is inserted. The cam follower 261 separated from the cam surface 271 of the cam 27 comes into contact with the cam surface 271 or the separately provided stopper 28 for limiting the amount of injected water, and one cycle of water injection is completed.

  The stopper 28 includes a female screw body 281 that is fixedly disposed, a male screw body 282 that is screwed to the female screw body 281, and a lock nut 283 that is screwed to the male screw body 282. The male screw body 282 is fixed to the female screw body 281 by tightening the lock nut 283. When the screwing position of the male screw body 282 with respect to the female screw body 281 is changed, the final end position of the cam lever 26 in the backward movement direction is changed. If this final end position is changed, the water injection end time is changed. When the screwing position of the male screw body 282 with respect to the female screw body 281 is deepened, the water injection end timing is delayed, and when the screwing position of the male screw body 282 with respect to the female screw body 281 is shallow, the water jetting end time is advanced.

  A pressure chamber 221 in the bellows 22 constituting the fluid spring means is connected to an air pressure source 30 via an air conduit 29. A pressure regulating valve 31 and a check valve 32 having a relief function are interposed on the air line 29. A throttle passage 34 is provided between the pressure regulating valve 31 and the pressure chamber 221 so as to be in parallel with the check valve 32. A pressure gauge 33 is connected to the air line 29 between the pressure regulating valve 31 and the check valve 32. The pressure gauge 33 is for measuring the air pressure between the pressure regulating valve 31 and the check valve 32. The air pressure between the pressure adjustment valve 31 and the check valve 32 is set by adjusting the pressure adjustment valve 31 while looking at the pressure gauge 33. The pressure regulating valve 31 having a relief function always maintains the air pressure between the pressure regulating valve 31 and the check valve 32 at the pressure set by the pressure regulating valve 31. That is, the pressure set by the pressure adjustment valve 31 is transmitted to the pressure chamber 221 in the bellows 22.

  As shown in FIG. 1B, a branch pipe 35 is connected to the discharge pipe 19 between the weft insertion pump 11 and the weft insertion nozzle 20, and a bypass nozzle 36 is connected to the end of the branch pipe 35. ing. The branch pipe 35 is a branch water path branched from the discharge pipe 19 as a water supply path. The branch pipe 35 and the bypass nozzle 36 constitute a diversion unit capable of diverting water from the discharge pipe 19 from the weft insertion pump 11 to the weft insertion nozzle 20.

  FIGS. 2A and 2B show the internal structure of the weft insertion nozzle 20. A cylindrical nozzle body 39 is fitted into the support hole 381 of the holder 38. A cap 40 is screwed onto the outer peripheral surface of the nozzle body 39 on the tip side. The holder 38 is clamped between the flange portion 391 formed on the rear end side of the nozzle body 39 and the cap 40 by tightening the cap 40, and is fastened to the holder 38. The support hole 381 around the nozzle body 39 is connected to the water supply passage 382 in the holder 38, and the annular chamber 41 between the outer peripheral surface of the nozzle body 39 and the support hole 381 is connected to the water supply passage 382. .

  A weft guide needle 42 is fitted in the cylinder of the nozzle body 39. An adjusting screw 43 is press-fitted and fixed to the rear end portion of the weft guide needle 42. The adjusting screw 43 that is a part of the weft guide needle 42 is screwed into the inner periphery of the flange portion 391, and the large-diameter portion 421 of the weft guide needle 42 is fitted into the inner hole 392 of the nozzle body 39. is doing. An annular water passage 44 between the small diameter portion 422 of the weft guiding needle 42 and the inner peripheral surface of the inner hole 392 of the nozzle body 39 communicates with the annular chamber 41 through a plurality of inflow ports 393. The inflow ports 393 are formed in the nozzle body 39 at regular intervals around the small diameter portion 422 of the weft guide needle 42. The outer peripheral surface of the small diameter portion 422 is slightly tapered.

  A cylindrical injection port forming body 45 is press-fitted and fixed in the cylinder at the tip of the nozzle body 39. A tapered hole 451 is formed on the inner peripheral surface of the injection port forming body 45 that is a part of the nozzle body 39. The tapered hole 451 has a shape that decreases in diameter from the rear end to the front end of the injection port forming body 45, and the periphery of the taper hole 451 extends from the rear end of the injection port forming body 45 to the rear end of the injection port forming body 45. Up to an intermediate step 452 with the tip. The small-diameter portion 422 on the distal end side of the weft guiding needle 42 is inserted into the injection port forming body 45 so as to pass through the inside of the tapered hole 451 and exceed the step 452. A throttle passage 453 is formed between the inner peripheral surface of the tapered hole 451 and the outer peripheral surface of the small diameter portion 422. The tip of the throttle passage 453 serves as an injection port 201 of the weft insertion nozzle 20.

A plurality of commutators 46 are disposed in the annular water channel 44.
When the screwing position of the adjustment screw 43 with respect to the nozzle body 39 is changed, the weft guiding needle 42 is displaced in the axial direction, and the passage cross-sectional area at the injection port 201 is changed. FIG. 2A shows a state where the adjusting screw 43 has entered the nozzle body 39 most deeply. In this state, the adjusting screw 43 and the weft guiding needle 42 are fixed to the nozzle body 39, and the passage cross-sectional area at the injection port 201 is minimum (> 0). FIG. 2B shows a state in which the passage cross-sectional area at the injection port 201 is maximized. The ring-shaped spacer 37 interposed between the adjustment screw 43 and the nozzle body 39 is fixed to the nozzle body 39 by tightening the adjustment screw 43, and the adjustment screw 43 and the needle 42 are also fixed to the nozzle body 39.

Sectional area passage in the injection port 201 can be varied in the range of 1.2 mm ² of 5 mm ^2. The inner diameter D of the weft guiding needle 42 is set to 1.3 mm or more. The value 1.3 mm of the inner diameter D is a value that can correspond to the maximum thickness of a commonly used weft.

  The water pumped from the weft insertion pump 11 flows into the water channel 44 through the water supply passage 382, the annular chamber 41, and the inlet 393. The water that has flowed into the water channel 44 passes through the commutator 46 and the throttle passage 453 adjacent to each other and is ejected from the ejection port 201. The weft Y passed through the weft guide needle 42 is inserted into the warp opening by water injection from the injection port 201.

  3A and 3B show the internal structure of the bypass nozzle 36. FIG. A chamber 471, a water discharge passage 472, and an injection port 473 are formed in the nozzle body 47, and the chamber 471 and the water discharge passage 472 are connected by the injection port 473. The chamber 471 communicates with the branch pipe 35. A needle 48 is fitted in the nozzle body 47. The outer peripheral surface of the distal end portion 481 of the needle 48 is tapered, and the distal end portion 481 enters the injection port 473 through the chamber 471.

  An adjusting screw 49 is press-fitted and fixed to the rear end portion of the needle 48. An adjustment screw 49 that is a part of the needle 48 is screwed into the nozzle body 47. A lock nut 52 is screwed onto the adjustment screw 49. The adjustment screw 49 is fixed to the nozzle body 47 by tightening the lock nut 52. When the screwing position of the adjustment screw 49 with respect to the nozzle body 47 is changed, the needle 48 is displaced in the axial direction, and the passage cross-sectional area at the injection port 473 is changed.

  A pointer 54 is attached to the nozzle body 47, and a scale (not shown) is attached to the operation disk 491 of the adjustment screw 49. The pointer 54 and the scale are for recognizing the passage cross-sectional area at the injection port 473, and the scale corresponding to the pointer 54 represents the actual passage cross-sectional area at the injection port 473.

FIG. 3A shows a state in which the adjustment screw 49 has entered the nozzle body 47 most deeply. In this state, the passage cross-sectional area at the injection port 473 is zero. FIG. 3B shows a state in which the passage cross-sectional area at the injection port 473 is maximized. The passage cross-sectional area at the injection port 473 can be changed between zero and 5 mm ² .

  A cylindrical joint 50 is fitted in the water discharge passage 472, and a flexible hose 51 is connected to the joint 50. The end of the hose 51 is led to the water tank 18. A vent hole 474 is formed in the upper part of the side surface of the nozzle body 47 so as to communicate with the water discharge passage 472. The inside of the water discharge passage 472 is an atmospheric pressure region.

  When the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 is not zero, the water pumped from the weft insertion pump 11 to the branch pipe 35 flows into the chamber 471. The water that has flowed into the chamber 471 is ejected from the ejection port 473 toward the water discharge passage 472. The water injected into the water discharge passage 472 is returned to the water tank 18 via the hose 51.

  As shown in FIG. 1B, the length of the water channel from the branch portion 53 between the discharge pipe 19 and the branch pipe 35 to the injection port 201 of the weft insertion nozzle 20, and from the branch portion 53 to the injection port 473 of the bypass nozzle 36. The channel length is almost the same (aligned). The injection port 473 of the bypass nozzle 36 and the injection port 201 of the weft insertion nozzle 20 are disposed at the same height position.

In the first embodiment, the following effects can be obtained.
(1-1) Water jetted from the bypass nozzle 36 is jetted toward the water discharge passage 472. The water discharge passage 472 communicates with the atmospheric pressure region via the vent hole 474, and the water discharge passage 472 is the atmospheric pressure region. In the configuration in which the water jetted from the bypass nozzle 36 is jetted toward the atmospheric pressure region, the jet port 473 of the bypass nozzle 36 never falls below atmospheric pressure (negative pressure). Therefore, due to the injection port 473 of the bypass nozzle 36 becoming atmospheric pressure or less (negative pressure), the inside of the discharge pipe 19, the branch pipe 35, the water channel inside the weft insertion nozzle 20, and the inside of the bypass nozzle 36. The problem of bubbles in the water channel is avoided. That is, the deterioration of the pressure waveform due to the bubbles generated when the injection port 473 (exit portion) of the bypass nozzle 36 becomes atmospheric pressure or less is avoided.

  FIGS. 5A, 5B, and 5C show pressure waveforms at the injection port 201 of the weft insertion nozzle 20 when the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 of the weft insertion device of this embodiment is changed. An experimental example is shown in which A curve G1 in FIG. 5A shows a pressure waveform when the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 is zero. A curve G2 in FIG. 5B shows a pressure waveform when the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 is 20% of the maximum passage cross-sectional area, and a curve G3 in FIG. The pressure waveform in the case where the passage cross-sectional area at 36 injection ports 473 is 50% of the maximum passage cross-sectional area is shown.

  5D, 5E, and 5F show a bypass of a weft insertion device in which the bypass nozzle 36 and the water tank 18 are connected by a steel pipe, and the water discharge passage 472 of the bypass nozzle 36 is not communicated with the atmospheric pressure region. An experimental example is shown in which the pressure waveform at the injection port 201 of the weft insertion nozzle 20 is measured when the passage cross-sectional area at the injection port 473 of the nozzle 36 is changed. A curve K1 in FIG. 5D shows a pressure waveform when the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 is zero. A curve K2 in FIG. 5 (e) shows a pressure waveform when the passage sectional area at the injection port 473 of the bypass nozzle 36 is 20% of the maximum passage sectional area, and a curve K3 in FIG. The pressure waveform in the case where the passage cross-sectional area at 36 injection ports 473 is 50% of the maximum passage cross-sectional area is shown. The experiments shown in FIGS. 5D, 5E, and 5F are performed after confirming that bubbles are not mixed in the pipe.

  When the pressure waveforms G1, G2, G3 and the pressure waveforms K1, K2, K3 are compared, when the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 is zero, it is naturally between the pressure waveform G1 and the pressure waveform K1. There is no difference. However, in the weft insertion device in which the bypass nozzle 36 and the water tank 18 are connected by a steel pipe, the disturbance of the pressure waveform increases as the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 increases. On the other hand, in the weft insertion device of the present embodiment (a configuration in which the bypass nozzle 36 injects water into the atmospheric pressure region), the pressure waveform is increased as the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 increases. The injection period is shortened while maintaining the rising waveform immediately after the start, and the pressure waveform is less disturbed.

  FIG. 6 shows the weft when the bypass nozzle 36 and the water tank 18 are connected by a steel pipe, and bubbles are contained in the pipe line in the weft insertion device in which the water discharge passage 472 of the bypass nozzle 36 is not communicated with the atmospheric pressure region. The experiment example which measured the pressure waveform in the injection nozzle 201 of the insertion nozzle 20 is shown. The pressure waveform Ko represents the occurrence of intense pulsation. When such a pressure waveform Ko is generated, the water jet ejected from the weft insertion nozzle 20 becomes a dumpling and becomes more diffuse and stable. I can't expect the weft insertion.

  However, according to the present embodiment, since the water discharge passage 472 of the bypass nozzle 36 is prevented from being at a pressure lower than the atmospheric pressure, bubbles are not generated in the pipe line and stable weft insertion can be performed. .

  (1-2) As disclosed in the drawing of Patent Document 1, in a configuration in which the length of the bypass pipe is considerably longer (about twice as long) as the pipe length between the pump and the weft insertion nozzle, the period is The long pressure pulsation component increases. In such a case, there arises a problem that the rising response of the injection pressure waveform is lowered. In addition, the shape of the pressure waveform itself is complicated.

  In the present embodiment, the length of the water passage from the branch portion 53 of the discharge pipe 19 and the branch pipe 35 to the weft insertion nozzle 20 and the length of the water passage from the branch portion 53 to the bypass nozzle 36 are made equal (aligned). ) Such equalization of the water channel length is effective for suppressing complication of the shape of the pressure waveform (deterioration of the pressure waveform).

  (1-3) When the height position of the injection port 201 of the weft insertion nozzle 20 is higher than the height position of the injection port 473 of the bypass nozzle 36, air flows from the injection port 201 of the weft insertion nozzle 20 due to the difference in water level between the two. While being sucked in, the same volume of water drops from the injection port 473 of the bypass nozzle 36. When the height position of the injection port 201 of the weft insertion nozzle 20 is lower than the height position of the injection port 473 of the bypass nozzle 36, air is sucked from the injection port of the bypass nozzle 36 due to the difference in water level therebetween, and the weft insertion nozzle The same volume of water drops from the nozzle. Then, bubbles are mixed in the water pipe (in the discharge pipe 19, the branch pipe 35, the water path in the weft insertion nozzle 20, the water path in the bypass nozzle 36, etc.), and the jet pressure waveform becomes worse. The structure in which the injection port 201 of the weft insertion nozzle 20 and the injection port 473 of the bypass nozzle 36 are arranged at the same height position is that air from the injection port 201 of the weft insertion nozzle 20 or the injection port 473 of the bypass nozzle 36 due to a water level difference. This is effective in avoiding inhalation.

  (1-4) FIG. 7 shows the thickness d of the weft Y, the weaving width, the amount of water Wy injected from the weft insertion nozzle 20 every weft insertion, and the injection from the bypass nozzle 36 every weft insertion. It is a graph which shows the relationship with the amount of water Wb made. The horizontal axis represents the thickness d of the weft Y, and the vertical axis represents the amount of water. d1 represents the minimum thickness of the weft Y used in the loom, and d2 represents the maximum thickness of the weft Y used in the loom. The sum (Wy + Wb) of the water amount Wy and the water amount Wb is equal to the supply water amount Wo pumped from the weft insertion pump 11 every weft insertion. The supply water amount Wo is equal to the volume removed by the backward movement of the plunger 14 (movement in the direction of arrow R in FIG. 4A) in the water storage chamber 123. The supply water amount Wo is determined on the assumption of the maximum weaving width H2 and the maximum thickness d2 of the weft Y used.

  The line E1 indicates the distribution ratio between the water amount Wy and the water amount Wb when the thickness d of the weft Y is changed in the range of [d1, d2] in the case of weaving with the minimum weaving width H1 allowed in the loom. Represents. The line E2 indicates a distribution ratio between the water amount Wy and the water amount Wb when the thickness d of the weft Y is changed in the range of [d1, d2] in the case of weaving with the maximum weaving width H2 allowed in the loom. Represents. The line E3 is when the thickness d of the weft Y is changed in the range of [d1, d2] when weaving is performed with a weaving width H3 smaller than the maximum weaving width and larger than the minimum weaving width. It is an example showing the distribution ratio of water quantity Wy and water quantity Wb.

  The loom speed and weaving width (for example, H3) are not changed, and the weft Y (for example, a weft having a thickness of d3 that is thicker than d1 and thinner than d2) is changed to a thicker weft (for example, a weft of thickness d4 that is thinner than d2). Suppose that In this case, as shown in FIG. 7, the distribution ratio between the water amount Wy and the water amount Wb is changed from the point X1 (distribution ratio Wy1: Wb1) to X2 (distribution ratio Wy2: Wb2). In order to make this change, the passage cross-sectional area at the injection port 201 of the weft insertion nozzle 20 is increased, and the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 is decreased by an amount corresponding to the increase in the passage cross-sectional area at the injection port 201. Make adjustments. Before and after this adjustment work, the sum of the passage cross-sectional area at the injection port 201 and the passage cross-sectional area at the injection port 473 does not change, but the thickness of the water jet injected from the weft insertion nozzle 20 increases.

  It is assumed that the loom rotational speed and the thickness of the weft Y (for example, d4) are not changed, and the weaving width H3 is changed to the maximum weaving width H2, for example. In this case, as shown in FIG. 7, the distribution ratio between the water amount Wy and the water amount Wb is changed from the point X2 (distribution ratio Wy2: Wb2) to the point X3 (distribution ratio Wy3: Wb3). In order to make this change, the passing cross-sectional area at the injection port 201 of the weft insertion nozzle 20 is left as it is, and adjustment work is performed to reduce the cross-sectional area at the injection port 473 of the bypass nozzle 36. As a result, the amount of water supplied to the weft insertion nozzle 20 increases.

  As described above, the combination of the weft insertion nozzle 20 capable of changing the amount of spray water and the bypass nozzle 36 capable of changing the amount of spray water changes the weaving conditions (specifically, the loom rotational speed, yarn type, weaving width). Therefore, it is possible to easily adjust the amount of spray water in the weft insertion nozzle 20 corresponding to the above.

(1-5) the variable range of the cross-sectional area passage in the injection port 201 of the weft insertion nozzle 20 is preferably in the range from 1.2 mm ² to 5 mm ^2. Further, the variable range of the cross-sectional area passage in the injection port 473 of the bypass nozzle 36 is preferably in the range of 0 mm ² to 5 mm ^2.

  (1-6) When the weaving width increases without changing the loom rotation speed, it is necessary to increase the injection speed of the water injected from the weft insertion nozzle 20. For this purpose, an adjustment operation for increasing the pressure in the pressure chamber 221 of the bellows 22 and increasing the injection pressure in the weft insertion nozzle 20 may be performed. According to the above equation (1), for example, when the loom speed is increased by 1.2 times, the pressure in the pressure chamber 221 of the bellows 22 is increased by 1.44 times (the square of 1.2). Good. This pressure adjustment can be easily performed by adjusting the pressure adjustment valve 31.

  (1-7) In the conventional water jet loom, when the thickness of the weft yarn is significantly changed in the range of 50 denier to 900 denier, the coil spring constituting the weft insertion pump is replaced, and the entire weft insertion pump It is inevitable to replace the weft and the weft insertion nozzle. If a large change in weaving conditions is anticipated at the current production plant, in preparation for the change, weft insertion pumps with different plunger diameters, coil springs with different spring constants and free lengths, weft insertion nozzles with different diameters, etc. Measures such as preparing parts for weft insertion as stock are taken. However, if there are no parts to be replaced due to circumstances, knowing that it is uneconomical, we will weigh in thin water with an excessive amount of water, or prepare to reduce the fabric quality and availability. There is no choice but to take measures such as wefting thick wefts with a small amount of water, or unavoidably lowering the loom speed.

  In this embodiment, a fluid spring means is used as a water injection pressure generating drive source in the weft insertion pump 11, and the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 that injects the water diverted from the discharge pipe 19 into the atmospheric pressure region. The passage cross-sectional area at the injection port 201 of the weft insertion nozzle 20 can be adjusted. As a result, it is possible to eliminate the problem of component replacement that has been unavoidable for adjusting the amount of water and the water injection pressure when the weaving conditions are greatly changed.

  In this embodiment, new parts are newly added, but considering the number of parts necessary for weaving in the entire range of weaving conditions in the prior art, the number of parts in this embodiment is larger than in the past. It is greatly reduced. If the present invention is applied to a loom for high-mix low-volume production that quickly responds to various weaving conditions, a number of effects such as increased functionality, reduced adjustment time, and reduced inventory parts can be expected. It is extremely high compared to

  Next, a description will be given of the bypass nozzle 36 </ b> A in FIG. 8 having a slightly different structure from the bypass nozzle 36 in the first embodiment. The same reference numerals are used for the same components as those in the first embodiment.

  The needle 48A is movable in the vertical direction with respect to the nozzle body 47A by rotating the operation disk 491 of the adjustment screw 49. The water that has passed through the ejection port 473A is ejected toward the water discharge passage 472A that penetrates the nozzle body 47A vertically. The water discharge passage 472A communicates with the atmospheric pressure region through the vent hole 474. The bypass nozzle 36A plays the same role as the bypass nozzle 36 in the first embodiment.

Next, a second embodiment schematically shown in FIG. 9 will be described. The same reference numerals are used for the same components as those in the first embodiment.
The height position of the injection port 361 of the bypass nozzle 36B is higher than the height position of the injection port 201 of the weft insertion nozzle 20, and the injection port 361 is directed downward. A U-shaped discharge main pipe 55 is connected to the bypass nozzle 36 </ b> B, and a discharge sub pipe 56 is connected to a side surface of the discharge main pipe 55. The connection part between the discharge sub-pipe 56 and the discharge main pipe 55 is at the height position of the injection port 201 of the weft insertion nozzle 20, and the discharge main pipe 55 can store water up to the connection part between the discharge sub-pipe 56 and the discharge main pipe 55. is there. The area between the water storage surface h1 closer to the injection port 361 of the bypass nozzle 36B and the injection port 361 of the bypass nozzle 36B is an air region covered by the discharge main pipe 55. The water storage surface h2 far from the injection port 361 of the bypass nozzle 36B is opened to the atmospheric pressure region by the vent hole 474, and the discharge main pipe beyond the height position of the connection portion between the discharge sub pipe 56 and the discharge main pipe 55. The water in 55 flows out from the connection part to the discharge sub-pipe 56. The water that flows out to the discharge sub-pipe 56 returns to the water tank 18 (see FIG. 1A) via the hose 51.

  The length of the discharge main pipe 55 extending from the bypass nozzle 36B to the connecting portion is set to a length that does not affect the pressure pulsation. When the flow resistance in the discharge main pipe 55 is extremely small, the air region between the water storage surface h1 and the injection port 361 of the bypass nozzle 36B can be regarded as an atmospheric pressure region, and injection is performed from the injection port 361 of the bypass nozzle 36B. The water to be discharged is injected into the atmospheric pressure region. That is, water does not fall from the injection port 201 of the weft insertion nozzle 20 or the injection port 361 of the bypass nozzle 36B while the operation of the loom is stopped, and air is not mixed into the pipe line due to the water drop. The discharge main pipe 55 and the discharge sub pipe 56 constitute water drop prevention means.

  When the present invention is applied to a multi-color weft insertion device, there is a limitation in installation space, and an ideal arrangement with respect to the height position of the weft insertion nozzle 20 and the bypass nozzle (the injection port 201 and the bypass nozzle of the weft insertion nozzle 20) May be unable to be obtained at the same height. The water drop prevention means of the second embodiment is effective in such a case.

Next, a third embodiment schematically shown in FIG. 10 will be described. The same reference numerals are used for the same components as those in the first embodiment.
The height position of the injection port 362 of the bypass nozzle 36C is above the height position of the injection port 201 of the weft insertion nozzle 20, and the injection port 362 is oriented in the horizontal direction. A discharge main pipe 57 is connected to the bypass nozzle 36C. The discharge main pipe 57 that receives the jet water from the bypass nozzle 36C includes a horizontal portion and a vertical portion, and the vertical portion extends upward. A discharge sub-pipe 58 is connected to the side surface of the vertical portion of the discharge main pipe 57. A check valve 59 is provided upstream of the connection portion between the discharge main pipe 57 and the discharge sub pipe 58. The check valve 59 closes the valve hole 592 by utilizing the weight of the valve body 591. A connection portion between the discharge sub-pipe 58 and the discharge main pipe 57 is opened to the atmospheric pressure region by a vent hole 474. The water in the discharge main pipe 57 that exceeds the height position of the connection portion between the discharge sub-pipe 58 and the discharge main pipe 57 flows out from the connection portion to the discharge sub-pipe 58. The water flowing out to the discharge sub-pipe 58 returns to the water tank 18 (see FIG. 1A) via the hose 51.

  The check valve 59 prevents the back flow of water in the discharge main pipe 57. Accordingly, water does not fall from the injection port 201 of the weft insertion nozzle 20 or the injection port 362 of the bypass nozzle 36C when the operation of the loom is stopped, and air is not mixed into the pipe line due to the water drop. The discharge main pipe 57, the discharge sub pipe 58, and the check valve 59 constitute water drop prevention means. The water drop prevention means of the third embodiment is effective as in the second embodiment when an ideal arrangement cannot be obtained with respect to the height positions of the weft insertion nozzle 20 and the bypass nozzle.

Note that the valve body 591 of the check valve 59 may be biased in the direction of closing the valve hole 592 by a spring force. In this case, it is desirable to make the spring force as small as possible.
Next, a fourth embodiment shown in FIGS. 11 to 14 will be described. The same reference numerals are used for the same components as those in the first embodiment.

  The servomotor type first electric drive means 66 shown in FIG. 11 drives the weft guide needle 42 (see FIGS. 2 (a) and 2 (b)) of the weft insertion nozzle 20 to provide a servomotor type second electric drive means 66. The electric drive means 67 drives the needle 48 of the bypass nozzle 36 (see FIGS. 3A and 3B). The first electric drive means 66 rotates the adjusting screw 43 (see FIGS. 2A and 2B) to change the passage cross-sectional area at the injection port 201 of the weft insertion nozzle 20. The second electric drive means 67 rotates the adjustment screw 49 (see FIGS. 3A and 3B) to change the passage cross-sectional area at the injection port 473 of the bypass nozzle 36.

  A potentiometer 77 is assembled to the weft insertion nozzle 20, and a potentiometer 78 is assembled to the bypass nozzle 36. The potentiometer 77 outputs an electrical signal corresponding to the position of the weft guide needle 42 (see FIGS. 2A and 2B), and the potentiometer 78 is connected to the needle 48 of the bypass nozzle 36 (FIGS. 3A and 3B). b) See] to output an electrical signal corresponding to the position.

  As shown in FIG. 12, a strain detection type yarn tension meter 60 and a gripper 61 are disposed on the weft path before the weft insertion nozzle 20. The weft Y is passed through a thread guide hole (not shown) of the yarn tension meter 60 and then passed between a fixed grip piece (not shown) and a movable grip piece (not shown) of the gripper 61. When the weft Y is not inserted, the movable grip piece is joined to the fixed grip piece, and the weft Y is gripped between the fixed grip piece and the movable grip piece. When the weft Y is inserted, the movable gripping piece is separated from the fixed gripping piece and the weft Y is released from the gripping action of the gripper 61. The weft Y released from the gripping action of the gripper 61 is inserted by water injection from the weft insertion nozzle 20. The load due to the tension of the weft Y is applied to the yarn tension meter 60, and the yarn tension meter 60 outputs an electrical signal corresponding to the load due to the tension of the weft Y.

  A distortion detection type jet head arrival detector 62 is disposed on the weft insertion end side. The jet head arrival detector 62 is on the injection path of water injected from the weft insertion nozzle 20. The water jet ejected from the weft insertion nozzle 20 collides with the jet head arrival detector 62. The jet head arrival detector 62 outputs an electrical signal corresponding to the load caused by the collision of the water jet.

  A load detector 63 is attached to the stopper 28 that defines the final position of the cam lever 26 in the backward movement direction. The load detector 63 outputs an electrical signal corresponding to the impact vibration acceleration when the cam lever 26 collides with the male screw body 282 of the stopper 28. The load detector 63 detects the end of water injection from the weft insertion nozzle 20.

  Electrical signals output from the potentiometers 77 and 78, the yarn tension meter 60, the jet head arrival detector 62, and the load detector 63 are sent to the monitoring control device 64. The monitoring control device 64 includes a signal processing unit 641 and a calculation unit 642. The potentiometers 77 and 78, the yarn tension meter 60, the jet head arrival detector 62, and the load detector 63 are connected to the signal processing unit 641. The signal processing unit 641 includes a rotary encoder 65 for detecting the rotation angle of the loom. Signal connected.

  The signal processing unit 641 detects the passage cross-sectional area N1 at the injection port 201 of the weft insertion nozzle 20 based on the electrical signal sent from the potentiometer 77. The signal processing unit 641 detects the passage cross-sectional area N2 at the injection port 473 of the bypass nozzle 36 based on the electrical signal sent from the potentiometer 78. Based on the electrical signal sent from the yarn tension meter 60 and the loom rotation angle detection information sent from the rotary encoder 65, the signal processing unit 641 completes the free flight end time θp at which the free flight of the weft Y ends. (The loom rotation angle when the flying weft Y changes from the free flying state to the restrained flying state) is detected. Based on the electrical signal sent from the jet head arrival detector 62 and the loom rotation angle detection information, the signal processing unit 641 determines that the head of the water jet ejected from the weft insertion nozzle 20 is the jet head arrival detector 62. Detect when the position is reached. The signal processing unit 641 detects the injection end timing θe of water injected from the weft insertion nozzle 20 based on the electrical signal sent from the load detector 63 and the loom rotation angle detection information.

  Then, the signal processing unit 641 outputs the detected free flight end time θp and the detected jet head arrival time θj to the calculation unit 642. Further, the signal processing unit 641 outputs the detected passage sectional area N1 detected by the weft insertion nozzle 20, the detected passage sectional area N2 detected by the bypass nozzle 36, and the detected water injection end timing θe to the control command device 76.

  The monitoring control device 64 including the signal processing unit 641 constitutes a free-running end timing detecting means for detecting a free-running end time θp at which the free-running of the weft Y ends together with the yarn tension meter 60 and the rotary encoder 65. . The supervisory control device 64, together with the jet head arrival detector 62 and the rotary encoder 65, detects the jet head arrival time for detecting the jet head arrival time when the head of the water jet sprayed from the weft insertion nozzle 20 reaches a predetermined position. Configure the means. The monitoring control device 64 constitutes, together with the load detector 63 and the rotary encoder 65, an injection end timing detecting means for detecting the water injection end timing. The monitoring control device 64 constitutes a first passage cross-sectional area detecting means for detecting a passage cross-sectional area at the injection port 201 of the weft insertion nozzle 20 together with the potentiometer 77. The monitoring control device 64 constitutes a second passage cross-sectional area detecting means for detecting a passage cross-sectional area at the injection port 473 of the bypass nozzle 36 together with the potentiometer 78.

  The computing unit 642 calculates the jet leading length Lp at the loom rotation angle θp representing the transition from the free-running state to the restrained flying state based on the signal processing result in the signal processing unit 641. The jet leading length Lp is calculated by a calculation method (calculation method based on FIG. 5 of Japanese Patent Application No. 2003-145355) described in Japanese Patent Application No. 2003-145457 by the applicant of the present application. The monitoring control device 64 including the calculation unit 642 is a jet leading length calculation unit that calculates a jet leading length.

  A pressure chamber 221 in the bellows 22 constituting a fluid spring means as a water jet generation drive source is connected to an air pressure source 30 through an air pipe 29. Hereinafter, the pressure in the pressure chamber 221 may be referred to as air spring pressure. An injection pressure adjusting means 68 is interposed on the air conduit 29. The injection pressure adjusting means 68 is a so-called aeroelectric conversion device that adjusts the throttle portion by electromagnetic means.

A decompression gradient adjusting means 69 is connected to the air conduit 29 between the injection pressure adjusting means 68 and the bellows 22. The configuration of the decompression gradient adjusting means 69 will be described with reference to FIG.
Three electromagnetic on-off valves 70, 71, 72 are connected in parallel to the air line 29, and accumulators 73, 74, 75 are connected to the electromagnetic on-off valves 70, 71, 72 in a one-to-one relationship. Yes. When the electromagnetic open / close valves 70, 71, 72 are excited to open, the accumulators 73, 74, 75 communicate with the air pipe 29. When the electromagnetic on / off valves 70, 71, 72 are demagnetized and closed, the communication between the accumulators 73, 74, 75 and the air conduit 29 is blocked.

  The volume of the accumulator 73 is equal to the minimum volume S of the pressure chamber 221 in the bellows 22. The accumulator 74 has a volume 2S that is twice the volume S of the accumulator 73, and the accumulator 75 has a volume 3S that is three times the volume S of the accumulator 73. The total volume of the accumulators 73, 74, and 75 communicating with the air pipe 29 can be selected from eight ways from 0 to 7S depending on the combination of opening and closing of the electromagnetic on-off valves 70, 71, and 72. Hereinafter, the total volume of the accumulators 73, 74, and 75 communicating with the air pipe 29 is referred to as a sub chamber volume.

  A curve Pa in the graph of FIG. 14 shows the relationship between the volume of the pressure chamber 221 and the pressure in the pressure chamber 221. The pressure Pi is a pressure when the volume of the pressure chamber 221 is maximum, and the pressure Pm is a pressure when the volume of the pressure chamber 221 is minimum. When the volume of the pressure chamber 221 increases, the pressure in the pressure chamber 221 is reduced so as to follow a curve Pa as indicated by an arrow U2 in FIG. As shown by the arrow U <b> 2 in FIG. 13, the degree of change in the air pressure in the pressure chamber 221 that follows the curve Pa is equal to the degree of change in the water injection pressure in the weft insertion nozzle 20.

  The degree of pressure reduction in the pressure chamber 221 indicated by the curve Pa decreases as the sub chamber volume increases. Hereinafter, the degree of pressure reduction in the pressure chamber 221 as indicated by the curve Pa is referred to as a pressure reduction gradient. The depressurization gradient can be adjusted by changing the combination of opening and closing of the electromagnetic on-off valves 70, 71 and 72.

As shown in FIGS. 11 and 12, the injection pressure adjusting means 68 and the electric drive means 66 and 67 are controlled by a control command device 76 constituted by a computer.
Information N1, N2, Lp, θp, θj of the passage cross-sectional areas N1, N2, the jet leading length Lp, the free flight end timing θp, the jet head arrival timing θj, and the water injection end timing θe obtained in the monitoring control device 64 , Θe are sent to the control command device 76. The control command device 76 includes a target value N1o of the cross-sectional area N1, a target value N2o of the cross-sectional area N2, a target value Lpo of the jet leading length Lp, a target value θpo of the free flight end time θp, and a jet head arrival time θj. And the target value σo of the variation of the free flight end time θp are set in advance. The control command device 76 responds to the deviation of the average value of each information N1, N2, Lp, θp, θj and the variation in the free flight end timing θp and the target values N1o, N2o, Lpo, θpo, θjo, σo. Thus, feedback control is performed on the adjustment state of the injection pressure adjusting means 68, the adjustment state of the decompression gradient adjusting means 69, and the adjustment states of the electric drive means 66 and 67. The variation of the average value of each piece of information N1, N2, Lp, θp, θj and the free flight end time θp is the average value of sampling data for a certain period, for example, 1 minute.

  The adjustment state of the injection pressure adjusting means 68 is a state in which the injection pressure adjusting means 68 adjusts the air spring pressure to a certain pressure. The adjusted state of the reduced pressure gradient adjusting unit 69 is a state in which the reduced pressure gradient adjusting unit 69 adjusts the sub chamber volume to a certain volume (one of eight volumes of 0 to 7S). The adjustment state of the first electric drive means 66 is a state in which the first electric drive means 66 adjusts the passage cross-sectional area at the injection port 201 of the weft insertion nozzle 20 to a certain passage cross-sectional area. is there. The adjusted state of the second electric driving means 67 is a state in which the second electric driving means 67 adjusts the passage cross-sectional area at the injection port 473 of the bypass nozzle 36 to a certain passage cross-sectional area. . The target of feedback control is the cross-sectional area N1 at the injection port 201 of the weft insertion nozzle 20, the cross-sectional area N2 at the injection port 473 of the bypass nozzle 36, the jet leading length Lp, the free flight end timing θp, the jet head The arrival time θj and the water injection end time θe. These controlled objects are controlled by adjusting the position of the weft guiding needle 42 of the weft insertion nozzle 20, the position of the needle 48 of the bypass nozzle 36, the air spring pressure, and the sub chamber volume. Changing the air spring pressure changes the water jet pressure. When the sub chamber volume is changed, the pressure reduction gradient of the water injection pressure changes. A change in the water injection period when the water injection pressure level or the pressure reduction gradient is changed can be compensated by changing the water injection end timing θe. The water injection end timing θe can be changed by changing the passage cross-sectional area at the injection port 473 of the bypass nozzle 36.

The control command device 76 performs control to sample the jet leading length data for a certain period, for example, 1 minute and repeat the adjustment.
In the fourth embodiment, the following effects can be obtained.

  (4-1) The cross-sectional area of the water jet according to the thickness of the weft Y can be changed by changing the passage cross-sectional area at the injection port 201 of the weft insertion nozzle 20. The passage cross-sectional area at the injection port 201 of the weft insertion nozzle 20 can be changed by changing the adjustment state of the first electric drive means 66. The first electric drive means 66 is an effective means for automatically adjusting the cross-sectional area of passage at the injection port 201 of the weft insertion nozzle 20.

  (4-2) The amount of water supplied to the weft insertion nozzle 20 side can be changed by changing the passage sectional area at the injection port 201 of the weft insertion nozzle 20 and the passage sectional area at the injection port 473 of the bypass nozzle 36. Further, the water injection end timing can be changed by changing the adjustment state of the second electric drive means 67. When the water injection end time is changed, the jet leading length can be changed.

  The passage cross-sectional area at the injection port 473 of the bypass nozzle 36 can be changed by changing the adjustment state of the second electric driving means 67. The second electrical drive means 67 is an effective means for automatically adjusting the passage cross-sectional area at the injection port 473 of the bypass nozzle 36.

  (4-3) The speed of the water jet can be changed by changing the water injection pressure. The water injection pressure can be changed by changing the adjustment state of the injection pressure adjusting means 68. The adjustment of the speed of the water jet can be used to adjust the jet leading length and the free flight end time, and the injection pressure adjusting means 68 is an effective means for automatically adjusting the jet leading length and the free flight end time. .

  (4-4) The speed of the water jet in the later stage of weft insertion can be changed by changing the pressure reduction gradient of the pressure waveform of the water injection pressure. The reduced pressure gradient can be changed by changing the adjustment state of the reduced pressure gradient adjusting means 69. When the decompression gradient is changed, the jet speed of the latter half of the water jet is changed and the flying speed of the weft of the latter half is changed, so that a speed difference between the weft and the jet water is generated and the jet leading length can be changed. The adjustment of the decompression gradient can be used for the adjustment of the jet leading length, and the decompression gradient adjusting means 69 is an effective means for automatically adjusting the jet leading length.

  (4-5) Conventionally, there is a limit to the automation of the weft insertion device in the water jet loom because work that must be relied on manually, such as disassembly of the device, replacement of parts, assembly, and screw fastening, is necessary. It was. However, in this embodiment, a weft insertion device for full automation is configured, and weaving that covers the entire range of weaving conditions can be performed without performing the above-described manual operation.

In the present invention, the following embodiments are also possible.
(1) In the first embodiment described above, the height position of the injection port 201 of the weft insertion nozzle 20 and the height position of the injection port 473 of the bypass nozzle 36 are the same. Even if the height position of the mouth 201 is different from the height position of the injection port 473 of the bypass nozzle 36, there is a case where water does not fall. This is a case where water does not drop due to the surface tension of water, and the difference between the height position of the injection port 201 of the weft insertion nozzle 20 and the height position of the injection port 473 of the bypass nozzle 36 is within 10 cm. If so, there is almost no water drop. That is, in the range where no water drops occur, a difference may be made between the height position of the injection port 201 of the weft insertion nozzle 20 and the height position of the injection port 473 of the bypass nozzle 36. That is, the injection port 201 of the weft insertion nozzle 20 and the bypass nozzle are arranged such that the height position of the injection port 201 of the weft insertion nozzle 20 and the height position of the injection port 473 of the bypass nozzle 36 do not cause water drop. 36 injection ports 473 may be arranged.

  (2) In the first embodiment described above, the water channel length from the branch portion 53 to the injection port 201 of the weft insertion nozzle 20 and the water channel length from the branch portion 53 to the injection port 473 of the bypass nozzle 36 are the same. However, these water channel lengths may be differentiated within a range where deterioration of the pressure waveform of water injection is allowed.

(3) A nozzle having the same configuration as the weft insertion nozzle 20 may be used as a bypass nozzle.
(4) It is desirable that the inner diameter of the discharge pipe 19 and the inner diameter of the branch pipe 35 be the same. Such identification of the inner diameter is effective in improving the pressure pulsation characteristics.

  (5) It is desirable that the material of the discharge pipe 19 and the material of the branch pipe 35 be the same. When the materials of the discharge pipe 19 and the branch pipe 35 are different, the expansion characteristics of the discharge pipe 19 and the expansion characteristics of the branch pipe 35 are different. The difference in expansion characteristics between the discharge pipe 19 and the branch pipe 35 causes deterioration of the pressure pulsation characteristics. The unification of the materials of the discharge pipe 19 and the branch pipe 35 is effective in suppressing the pressure pulsation characteristics.

  (6) A bypass nozzle may be incorporated in the holder 38 of the weft insertion nozzle 20. That is, water may be diverted from the water supply passage 382 in the holder 38 to the bypass nozzle. In this way, the pipe line length (water channel length) between the weft insertion nozzle 20 and the bypass nozzle becomes very short. By reducing the length of the water channel from the branch part 53 of the discharge pipe 19 and the branch pipe 35 to the weft insertion nozzle 20 and the length of the water path from the branch part 53 to the bypass nozzle 36 as much as possible, pressure pulsation components having a long cycle are suppressed. This is desirable.

  (7) When it is not necessary to cover the entire range of weaving conditions, for example, there are cases where the change width between the loom rotation speed and the weaving width is small, and only the weft type (yarn thickness) may be changed. In such a case, the distribution ratio between the amount of water supplied to the weft insertion nozzle 20 and the amount of water supplied to the bypass nozzle 36 is the main adjustment object, and it is not necessary to change the water injection pressure greatly. Therefore, in such a case, a weft insertion pump using a coil spring may be used.

(8) A linear solenoid may be used as an electric driving means for changing the position of the weft guiding needle 42 in the weft insertion nozzle 20.
(9) A linear solenoid may be used as an electric driving means for changing the position of the needle 48 in the bypass nozzle 36.

1st Embodiment is shown and (a) is a general view. (B) is a partial top view. (A), (b) is sectional drawing which shows the weft insertion nozzle 20. FIG. (A), (b) is sectional drawing which shows the bypass nozzle 36. FIG. (A) is a general view. (B) is sectional drawing of the weft insertion pump 11. FIG. (A), (b), (c) is a graph which shows the example of the pressure waveform in 1st Embodiment. (D), (e), (f) is a graph which shows the example of the pressure waveform at the time of connecting the bypass nozzle 36 and the water tank 18 with the steel pipe. The graph which shows the example of a pressure waveform when a bubble is mixed in the case where the bypass nozzle 36 and the water tank 18 are connected with a steel pipe. The graph which shows distribution ratio of the amount of water supply to the weft insertion nozzle 20 side, and the amount of water supply to the bypass nozzle 36 side. Sectional drawing which shows another example of a bypass nozzle. The schematic diagram which shows 2nd Embodiment. The schematic diagram which shows 3rd Embodiment. The whole figure showing a 4th embodiment. FIG. The schematic diagram which shows the decompression gradient adjustment means 69. FIG. The graph which shows the relationship between the volume of the pressure chamber 221 and the pressure in the pressure chamber 221.

Explanation of symbols

  11 ... Weft insertion pump. 19: Discharge pipe as a water supply route. 20 ... Weft insertion nozzle. 201: Jetting nozzle of weft insertion nozzle. 22 ... Bellows constituting fluid spring means. 221 ... Pressure chamber constituting fluid spring means. 35 ... Branch pipe as a branch water path. 36, 36A, 36B, 36C ... bypass nozzles. 361, 362, 473 ... Bypass nozzles. 53 ... Branch part. 55... A discharge main pipe constituting water drop prevention means in the second embodiment. 56: A discharge sub-pipe constituting water drop prevention means in the second embodiment. 57... A discharge main pipe constituting water drop prevention means in the third embodiment. 58 ... A discharge sub-pipe constituting water drop prevention means in the third embodiment. 59... A check valve constituting water drop prevention means in the third embodiment. 66: First electric driving means. 67. Second electrical drive means. Y ... Weft. h1, h2 ... Water storage surface.

Claims (10)

In the weft insertion device in the water jet loom that injects the water supplied from the weft insertion pump from the weft insertion nozzle and inserts the weft.
A diversion unit capable of diverting a part of water from a water supply path from the weft insertion pump to the weft insertion nozzle, and the diversion unit includes a branch water path branched from the water supply path, and an end of the branch water path A bypass nozzle connected to the bypass nozzle, wherein the bypass nozzle is formed with an injection port and a water discharge passage connected to the injection port and communicating with an atmospheric pressure region through a ventilation portion. A hose whose end is led to a water tank is connected to an outlet of the water discharge passage formed at a position different from the section, and water sprayed from the bypass nozzle is directed toward the water discharge passage communicating with the atmospheric pressure region. A weft insertion device in a water jet loom in which water jetted and jetted into the water discharge passage returns to the water tank from the outlet through the hose.   The weft length in the water jet loom according to claim 1, wherein a water channel length from the branch part of the water supply path and the branch water path to the weft insertion nozzle is aligned with a water path length from the branch part to the bypass nozzle. Putting device.   The weft insertion device in the water jet loom according to any one of claims 1 and 2, further comprising a water drop prevention means for preventing water drop from the weft insertion nozzle and the bypass nozzle.   The water drop prevention means includes: a nozzle position of the weft insertion nozzle; and a height position of the injection opening of the weft insertion nozzle and a height position of the injection opening of the bypass nozzle so as not to cause a water drop. The weft insertion device in the water jet loom according to claim 3, wherein the injection port of the bypass nozzle is arranged.   5. The weft insertion device in the water jet loom according to claim 4, wherein the water drop prevention means has a configuration in which an injection port of the weft insertion nozzle and an injection port of the bypass nozzle are arranged at the same height position. The water passage according to any one of claims 1 to 5 , wherein a cross-sectional area passing through the injection port of the weft insertion nozzle can be changed, and a cross-sectional area passing through the injection port of the bypass nozzle can be changed. Weft insertion device in jet loom. Sectional area passage in the injection port of the weft insertion nozzle is changed by the first electrical driving means, the cross-sectional area passage in the bypass nozzle of claim 6 which is modified by a second electrical drive means Weft insertion device in water jet loom. Sectional area passage in the injection port of the weft insertion nozzle, the weft insertion apparatus in a water jet room according to any one of claims 6 and claim 7 is variable in the range of 1.2 mm ² to 5 mm ^2. Sectional area passing in the bypass nozzle weft insertion device in a water jet room according to any one of claims 6 to 8 is variable in a range of 0 mm ² to 5 mm ^2. The water spring according to any one of claims 1 to 9 , wherein a fluid spring means using a pressure of a compressible gaseous fluid as a spring force is used as a water injection pressure generating drive source in the weft insertion pump. Weft insertion device in jet loom .

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