BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a spinning machine.
2. Description of the Related Art
As a technology related to a conventional spinning machine, for example, a spinning machine described in JP 2013-067882 A (Patent Document 1) is known. The spinning machine described in Patent Document 1 includes a machine main body having a plurality of spinning units and a drive end box arranged at an end portion of the machine main body. To the drive end box, compressed air is supplied from a compressed air supply source. Inside the drive end box, there is arranged an air supplying section that appropriately adjusts compressed air and supplies the compressed air to each section of the spinning machine. The air supplying section has a regulator for adjustment of a pressure of the compressed air. The compressed air adjusted to have an appropriate air pressure by the air supplying section is supplied to each section of the spinning machine via a duct, a tube, or the like.

In the technology described above, it is desired to reduce a pressure of compressed air supplied by the compressed air supply source in order to reduce power consumption, for example, under demand for energy saving
BRIEF SUMMARY OF THE INVENTION An object of one aspect of the present invention is to provide a spinning machine capable of reducing a pressure of compressed air supplied by a compressed air supply source.
A spinning machine comprises a spinning unit that produces a yarn and winds the yarn into a package; a first pipe that distributes compressed air supplied from a compressed air supply source; a second pipe that distributes spinning air to be supplied to the spinning unit; a first regulator that is connected to the first pipe and the second pipe and that reduces a pressure of the compressed air supplied from the first pipe to allow the compressed air to flow out to the second pipe; a third pipe that distributes the compressed air supplied from the compressed air supply source; a pressure increasing device that is connected to the third pipe and that increases a pressure of the compressed air supplied from the third pipe; and a fourth pipe that

allows the compressed air increased in pressure by the pressure increasing device to flow into a pilot port of the first regulator.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view illustrating a spinning machine according to an embodiment;
FIG. 2 is a side view illustrating the spinning machine of FIG. 1;
FIG. 3 is a side cross-sectional view illustrating a pneumatic spinning device of FIG. 1 and a peripheral configuration thereof;
FIG. 4 is a diagram illustrating a configuration of an air supplying section of the spinning machine of FIG. 1;
FIG. 5 is a cross-sectional view illustrating a first regulator of FIG. 4;
FIG. 6 is a perspective view illustrating the first regulator of FIG. 4 and a peripheral configuration thereof;
FIG. 7 is an enlarged perspective view illustrating the first regulator of FIG. 6 and a peripheral configuration thereof; and
FIG. 8 is a diagram illustrating a configuration

of an air supplying section of a spinning machine according to an alternative embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Hereinafter, an embodiment will be described in detail with reference to the attached drawings. In the description of the drawings, the same reference numerals are given for the same or corresponding elements, and redundant explanations are omitted.
As illustrated in FIG. 1, a pneumatic spinning machine (spinning machine) 1 includes a plurality of spinning units 2, a yarn joining cart 3, a doffing cart (not illustrated), a first end frame 4, and a second end frame (frame) 5. The plurality of the spinning units 2 are arranged in a row. Each of the spinning units 2 is adapted to produce a yarn Y and to wind the yarn Y into a package P. The yarn joining cart 3 is adapted to perform a yarn joining operation in a spinning unit 2 when the yarn Y is cut, or is broken for some reason in such a spinning unit 2. The doffing cart is adapted to doff the package P and to supply a new bobbin B to the spinning unit 2 when the package P is fully-wound in such a spinning unit 2.
The first end frame 4 accommodates, for example, a

collecting device adapted to collect a fiber waste, a yarn waste, and the like generated in the spinning units 2.
The second end frame 5 accommodates an air supplying section 100 adapted to adjust air pressure of compressed air to be supplied to the pneumatic spinning machine 1 and to supply the air to each section of the pneumatic spinning machine 1, a drive motor adapted to supply power to each section of the spinning unit 2, and the like. The second end frame 5 is provided with a machine control device 5a, a display screen 5b, an input key 5c, and a pressure display section 5d. The machine control device 5a is adapted to intensively manage and control each section of the pneumatic spinning machine 1. The display screen 5b is capable of displaying information relating to setting and/or a status, or the like of the spinning units 2. An operator can perform a setting operation of the spinning units 2 by performing an appropriate operation with the input key 5c. The pressure display section 5d displays at least a pressure value of spinning air (compressed air) (described later) The pressure display section 5d is not particularly limited, and various known display sections can be used as long as the pressure value of the spinning air can be

displayed. The pressure display section 5d may be included in the display screen 5b.
Each spinning unit 2 includes a draft device 6, a pneumatic spinning device (spinning device) 7, a yarn monitoring device 8, a tension sensor 9, a yarn accumulating device 11, a waxing device 12, and a winding device 13 in such an order from the upstream side in a travelling direction of the yarn Y. A unit controller 10 is provided for every predetermined number of the spinning units 2 and is adapted to control operations of the spinning units 2. The unit controller 10 is configured by, for example, one or more computer devices. The unit controller 10 includes a central processing unit (CPU) which is a processor, a random access memory (RAM) or a read only memory (ROM) which is a recording medium, and the like. The unit controller 10 executes various controls by loading a program or the like on hardware such as the CPU and the RAM.
The draft device 6 drafts a sliver (fiber bundle)
5. The pneumatic spinning device 7 produces the yarn Y
by twisting a fiber bundle F drafted by the draft device
6, with a whirling airflow. The yarn monitoring device
8 monitors the travelling yarn Y between the pneumatic
spinning device 7 and the yarn accumulating device 11,

and detects the presence or absence of a yarn defect. The yarn defects to be detected include excess hairiness. Further, for example, at least any one of a nep, a slub, a colored yarn defect, an abnormal yarn count, a weak yarn, and a change in physical characteristics of the yarn may be included as the yarn defect. When detecting the yarn defect, the yarn monitoring device 8 transmits a yarn defect detection signal to the unit controller 10.
The tension sensor 9 is adapted to measure tension of the travelling yarn Y between the pneumatic spinning device 7 and the yarn accumulating device 11, and to transmit a tension measurement signal to the unit controller 10. When the unit controller 10 determines a presence of an abnormality based on a detection result of the yarn monitoring device 8 and/or the tension sensor 9, the yarn Y is cut in the spinning unit 2.
The yarn accumulating device 11 is adapted to eliminate slackening of the yarn Y between the pneumatic spinning device 7 and the winding device 13. The waxing device 12 is adapted to apply wax to the yarn Y between the yarn accumulating device 11 and the winding device 13. The winding device 13 is adapted to wind the yarn Y around the bobbin B to form the package P. The winding

device 13 has a cradle arm 14, a winding drum 15, and a traverse mechanism 16. The cradle arm 14 rotatably supports the bobbin B.
The yarn joining cart 3 is a work cart that travels to the spinning unit 2 in which the spun yarn Y has been cut or disconnected, to perform a yarn joining operation in such a spinning unit 2. As illustrated in FIG. 2, the yarn joining cart 3 has a yarn joining device 3a, a suction nozzle 3b, and a suction mouth 3c. The yarn joining device 3a is a splicer device that twists yarn ends with each other by means of a whirling airflow. The yarn joining device 3a is not limited to the splicer device, but a mechanical knotter or the like can be employed, for example.
The suction nozzle 3b can generate a suction airflow at a distal end thereof to suction in and capture the yarn Y fed from the pneumatic spinning device 7. The suction mouth 3c can generate a suction airflow at a distal end thereof to suction in and capture the yarn Y from the package P supported by the winding device 13. Each of the suction nozzle 3b and the suction mouth 3c rotates with the captured yarn Y to guide the yarn Y to a position where the yarn Y can be introduced into the yarn joining device 3a. With such a yarn joining cart

3, the yarn Y from the pneumatic spinning device 7 guided by the suction nozzle 3b and the yarn Y from the package P guided by the suction mouth 3c are joined by the yarn joining device 3a. The yarn joining cart 3 can operate by using compressed air supplied from a yarn joining pipe 105 described later. The configuration of the yarn joining cart 3 is not particularly limited, and it is sufficient that the yarn joining operation can be performed.
As illustrated in FIG. 3, the pneumatic spinning device 7 includes a first holder 51 and a second holder 52. The first holder 51 has a fiber guiding section 53 and a nozzle block 54. The second holder 52 has a hollow guide shaft body 55. In FIG. 3, for example, the fiber guiding section 53 and the nozzle block 54 are illustrated as separate members, but the fiber guiding section 53 and the nozzle block 54 may be configured as a single member (integrally configured).
The fiber guiding section 53 guides the sliver S drafted by the draft device 6 into the pneumatic spinning device 7. The fiber guiding section 53 is provided with a fiber introduction port 56 and a guide needle 57. The sliver S drafted by the draft device 6 is introduced from the fiber introduction port 56 to the fiber guiding

section 53, and guided into a spinning chamber 59 so as to be wound around the guide needle 57.
The nozzle block 54 is formed with a plurality of nozzles 58. The nozzle block 54 forms the spinning chamber 59, together with the fiber guiding section 53 and the hollow guide shaft body 55. The pneumatic spinning device 7 ejects spinning air (compressed air) supplied from a spinning pipe 102, which will be described later, from the nozzle 58 into the spinning chamber 59 to cause a whirling airflow to act on the sliver S in the spinning chamber 59. Note that the guide needle 57 may be omitted, and a downstream side of the fiber guiding section 53 may have a function of the guide needle 57 .
At an axial center of the hollow guide shaft body 55, a yarn passage 60 is formed. One end of the fibers of the sliver S is swung around a distal end of the hollow guide shaft body 55 by the spinning air injected from the nozzle 58. The sliver S is then guided as the yarn Y through the yarn passage 60 and to the outside of the pneumatic spinning device 7 from a yarn outlet (not illustrated) on a downstream side.
As illustrated in FIG. 4, the air supplying section 100 includes an introduction pipe (first pipe) 101, the

spinning pipe (second pipe) 102, a mist separator 110, an introduction branch pipe (third pipe) 103, a first regulator 120, a pressure increasing device 130, a pilot pipe (fourth pipe) 104, the yarn joining pipe (fifth pipe) 105, and a second regulator 140. The air supplying section 100 is arranged in the second end frame 5 of the pneumatic spinning machine 1.
The introduction pipe 101 is a pipe that distributes compressed air supplied from a compressed air supply source 20. The compressed air from the compressed air supply source 20 is introduced into the introduction pipe 101. Specifications, a shape, a length, a material, and the like of the introduction pipe 101 are not particularly limited, and a highly-rigid pipe or a flexible pipe may be adopted (the same applies to other pipes below), for example.
The compressed air supply source 20 is installed at a predetermined place (factory or the like) where the pneumatic spinning machine 1 is installed. In the present embodiment, the compressed air supply source 20 is installed outside the pneumatic spinning machine 1, independently of the pneumatic spinning machine 1. The compressed air supply source 20 has an air compressor 21 and an air tank 22. The air compressor 21 compresses

air. The air compressor 21 is, for example, an electric compressor that pressurizes and discharges air by driving an electric motor. The air tank 22 temporarily stores the compressed air compressed by the air compressor 21. The introduction pipe 101 is connected to the air tank 22. Accordingly, the compressed air in the air tank 22 is supplied to the pneumatic spinning machine 1 via the introduction pipe 101. In addition, the air tank 22 is connected with an introduction pipe of another pneumatic spinning machine in addition to the introduction pipe 101 of the pneumatic spinning machine 1, and the compressed air is supplied to another pneumatic spinning machine through such an introduction pipe. An introduction pipe of another textile machine may be connected to the air tank 22.
The spinning pipe 102 is a pipe that distributes spinning air, which is compressed air supplied to the spinning unit 2. The spinning pipe 102 includes a straight pipe 102x extending in a direction in which the respective spinning units 2 are arranged. A plurality of unit pipes 114 are connected to the straight pipe 102x. The spinning air of the spinning pipe 102 flows to each spinning unit 2 via the straight pipe 102x and each unit pipe 114. The number of the unit pipes 114

provided is the same as the number of the spinning units 2, and the unit pipes 114 are each provided for each of the spinning units 2. An upstream side of the unit pipe 114 associated with each spinning unit 2 is connected to the straight pipe 102x, and a downstream side thereof is connected to the nozzle 58 (see FIG. 3) of the pneumatic spinning device 7 of the spinning unit 2.
The mist separator 110 is provided to the introduction pipe 101. The mist separator 110 separates and removes particulate substances in the compressed air flowing through the introduction pipe 101, from the compressed air. The mist separator 110 is not particularly limited, and various known mist separators can be used.
The introduction branch pipe 103 is a pipe branched from the introduction pipe 101, and is a pipe that distributes the compressed air supplied from the compressed air supply source 20. An upstream side of the introduction branch pipe 103 is connected to the introduction pipe 101 (in the illustrated example, a portion located downstream than the mist separator 110).
As illustrated in FIG. 5, the first regulator 120 is connected to a downstream side of the introduction pipe 101 and an upstream side of the spinning pipe 102.

The first regulator 120 reduces a pressure of the compressed air in the introduction pipe 101, and causes the compressed air to flow out to the spinning pipe 102 as spinning air. The first regulator 120 is located inside the second end frame 5 (see FIG. 6). The first regulator 120 is an external pilot regulator, and has an inflow port 121, an outflow port 122, a pilot port 123, a pilot chamber 124, a pilot-side diaphragm (diaphragm) DX, a pilot valve 125, a pressure regulation spring 126, a pressure adjustment handle 127, a main valve 128, a diaphragm chamber 129, and a main-valve-side diaphragm DY.
A downstream side of the introduction pipe 101 is fixed to the inflow port 121. An upstream side of the spinning pipe 102 is fixed to the outflow port 122. A downstream side of the pilot pipe 104 is fixed to the pilot port 123. The pilot chamber 124 is a space communicating with the pilot port 123. The pilot-side diaphragm DX is a film-shaped member that constitutes a wall of the pilot chamber 124. The pilot valve 125 is a valve provided between the pilot port 123 and the pilot chamber 12 4.
The pressure regulation spring 126 is a spring that urges the pilot-side diaphragm DX. The pressure

adjustment handle 127 is a handle that can be rotated around a rotational axis G. Rotating the pressure adjustment handle 127 allows adjustment of an urging force of the pressure regulation spring 126, to adjust a pressure of the spinning air discharged by the first regulator 120. The main valve 128 is a valve provided on a flow path PA passing from the inflow port 121 to the outflow port 122. The diaphragm chamber 129 is a space communicating with the outflow port 122 side of the flow path PA via a feedback hole FH. The main-valve-side diaphragm DY is a film-shaped member that constitutes a wall of the diaphragm chamber 129.
In such a first regulator 120, pressure from the pilot port 123 side (a pilot supply pressure) is introduced into the pilot chamber 124, and the pressure in the pilot chamber 124 and the urging force of the pressure regulation spring 126 oppose each other to cause an equilibrium state. Then, the pressure in the pilot chamber 124 pushes and opens the main valve 128 via the main-valve-side diaphragm DY, and the pressure is guided to the outflow port 122 side. At the same time, the pressure is introduced into the diaphragm chamber 129 through the feedback hole FH, and the pressure of the spinning air flowing out from the outflow port 122 is

set.
As illustrated in FIG. 4, the pressure increasing device 130 is connected to the introduction branch pipe 103. The pressure increasing device 130 is a device that increases a pressure of the compressed air from the introduction branch pipe 103. The pressure increasing device 130 includes a pressure increasing valve 131 and an air tank (tank) 132 connected to an outlet side of the pressure increasing valve 131. The pressure increasing valve 131 increases a pressure of the compressed air. The air tank 132 temporarily stores the compressed air increased in pressure by the pressure increasing valve 131. The pressure increasing valve 131 and the air tank 132 are not particularly limited, and various known pressure increasing valves and air tanks can be used. The air tank 132 may be omitted. The air tank 132 (that is, the outlet side of the pressure increasing device 130) is connected with an upstream side of the pilot pipe 104 and an upstream side of the yarn joining pipe 105. As illustrated in FIG. 6, the pressure increasing device 130 is arranged inside the second end frame 5.
The pilot pipe 104 is a pipe that allows the compressed air increased in pressure by the pressure

increasing device 130 to flow into the pilot port 123. The yarn joining pipe 105 supplies the compressed air increased in pressure by the pressure increasing device 130 to the yarn joining cart 3.
As illustrated in FIGS. 6 and 7, the second regulator 140 is provided to the pilot pipe 104. The second regulator 140 is a regulator that reduces a pressure of the compressed air flowing through the pilot pipe 104. The second regulator 140 is a direct-operated regulator. The second regulator 140 is held by a stay 142 on one side of the first regulator 120 in a predetermined direction, which is a horizontal direction orthogonal to (intersecting) the rotational axis G of the pressure adjustment handle 127 of the first regulator 120.
The stay 142 exhibits a bent plate shape. The stay 142 has a horizontal portion 142a and a vertical portion 142b that is continuous from the horizontal portion 142a by being bent downward. In the illustrated example, the stay 142 is fixed to the introduction pipe 101. The stay 142 hides at least a part of the second regulator 140 when viewed from one side in the predetermined direction. That is, the second regulator 140 is arranged at a corner portion formed by the horizontal portion

142a and the vertical portion 142b, and a part of the second regulator 140 is covered with the stay 142.
The second regulator 140 has a pressure adjustment knob 144 for adjustment of a pressure of the pressure-reduced compressed air. The pressure adjustment knob 144 is provided so as to penetrate outward from the stay 142. An inner diameter of the pilot pipe 104 provided with such a second regulator 140 is smaller on a downstream side of the second regulator 140 than that on an upstream side. In other words, a portion of the pilot pipe 104 connected to an outlet side of the second regulator 140 is smaller than a portion of the pilot pipe 104 connected to an inlet side of the second regulator 140.
As described above, in the pneumatic spinning machine 1, the pilot supply pressure of the first regulator 120 is required to be a pressure equal to or higher than a certain value according to a pressure of the spinning air. For example, when the pressure of spinning air is 0.5 MPa, a pilot supply pressure of 0.6 MPa (differential pressure 0.1 MPa) or more is required. In this respect, in the pneumatic spinning machine 1, the compressed air from the compressed air supply source 20 does not directly flow into the pilot port 123 of the

first regulator 120, but instead, flows into the pilot port 123 after being increased in pressure by the pressure increasing device 130. Therefore, the pilot supply pressure equal to or higher than a certain value can be acquired from the compressed air increased in pressure by the pressure increasing device 130. The pilot supply pressure becomes less dependent on the pressure of the compressed air supplied by the compressed air supply source 20. As a result, the pressure of the compressed air supplied by the compressed air supply source 20 can be reduced as compared with a case where the compressed air from the compressed air supply source 20 directly flows into the pilot port 123.
In the pneumatic spinning machine 1, the first regulator 120 is a large-capacity regulator, but a consumption flow rate of the compressed air flowing into the pilot port 123 can be very small. In the pneumatic spinning machine 1, even if the pressure of the compressed air from the compressed air supply source 20 fluctuates, the pilot-side diaphragm DX can be stably operated to reduce the fluctuation of the pressure of the spinning air.
In the pneumatic spinning machine 1, the first regulator 120 is an external pilot regulator, and has

the pilot chamber 124 communicating with the pilot port 123, the pilot-side diaphragm DX constituting the wall of the pilot chamber 124, and the pressure regulation spring 126 that urges the pilot-side diaphragm DX. In this case, a configuration that achieves the above effect can be concretely realized.
The pneumatic spinning machine 1 includes the second regulator 140 provided to the pilot pipe 104 to reduce the pressure of the compressed air flowing through the pilot pipe 104. The compressed air supplied from the compressed air supply source 20 flows into the introduction branch pipe 103, and the compressed air is increased in pressure by the pressure increasing device 130. The pressure-increased compressed air flows through the pilot pipe 104 and is reduced in pressure by the second regulator 140. In this case, the second regulator 140 can adjust the pilot supply pressure to be a more appropriate pressure. Further, in this case, the second regulator 140 inhibits excessive increase of the pilot supply pressure, which enables avoidance of large fluctuations in the pressure of the spinning air due to excessively high pilot supply pressure.
In the pneumatic spinning machine 1, the first regulator 120 has the pressure adjustment handle 127

that can rotate around the rotational axis G. The second regulator 140 is held by the stay 142 on one side of the first regulator 120 in a predetermined direction orthogonal to the rotational axis G. The stay 142 hides at least a part of the second regulator 140 when viewed from one side in the predetermined direction. Accordingly, the first regulator 120 can be arranged such that a user can easily touch the pressure adjustment handle 127 of the first regulator 120, and the second regulator 140 can be arranged such that the second regulator 140 is hidden behind the stay 142 on a side of the first regulator 120. That is, the second regulator 140 can be arranged such that it is difficult for the user to touch.
In the pneumatic spinning machine 1, an inner diameter of the pilot pipe 104 on the downstream side of the second regulator 140 is smaller than that on the upstream side. This can reduce a pressure loss when the compressed air flows through the pilot pipe 104. Note that, for example, when the inner diameter of the pilot pipe 104 is sufficiently large and the like, the inner diameter of the pilot pipe 104 may be the same on the upstream side and the downstream side of the second regulator 140.

In the pneumatic spinning machine 1, the pilot pipe 104 and the yarn joining pipe 105 are connected to the outlet side of the pressure increasing device 130. In this case, the compressed air increased in pressure by the pressure increasing device 130 can be supplied to the yarn joining cart 3. The pressure increasing device 130 can also be used as a device for supplying the compressed air to various devices of the yarn joining cart 3 in addition to being used as a device for acquisition of the pilot supply pressure, which can simplify the configuration of the entire pneumatic spinning machine 1. Since the number of the pressure increasing devices 130 in the pneumatic spinning machine 1 does not increase, it is possible to avoid an increase in the cost of the pneumatic spinning machine 1 itself. In the yarn joining cart 3, the yarn joining work can be performed by using the compressed air increased in pressure by the pressure increasing device 130.
In the pneumatic spinning machine 1, the pressure increasing device 130 includes the pressure increasing valve 131 and the air tank 132. The pilot pipe 104 and the yarn joining pipe 105 are connected to the air tank 132. In this case, the pressure increasing device 130 can stably supply the pressure-increased compressed air.

The pneumatic spinning machine 1 includes the pressure display section 5d that displays a pressure value of spinning air. In this case, it can be easily checked by the pressure display section 5d whether or not the pressure of the spinning air is normal.
In the pneumatic spinning machine 1, the spinning unit 2 includes the pneumatic spinning device 7 having the fiber guiding section 53, the nozzle 58, and the hollow guide shaft body 55. The spinning pipe 102 is connected to the nozzle 58. As a result, the spinning air can be stably supplied to the nozzle 58 of the pneumatic spinning device 7.
In the pneumatic spinning machine 1, an upstream side of the introduction branch pipe 103 is connected to the introduction pipe 101. In this case, for example, a length of the introduction branch pipe 103 can be shortened as compared with a case where the upstream side of the introduction branch pipe 103 is directly connected to the compressed air supply source 20, and the configuration of the entire pneumatic spinning machine 1 can be made compact.
FIG. 8 is a diagram illustrating a configuration of an air supplying section 100 of a spinning machine according to an alternative embodiment. As illustrated

in FIG. 8, the pilot pipe 104 may be provided with a mist separator 150 and a pressure gauge 160. The mist separator 150 removes particulate substances in the compressed air flowing through the pilot pipe 104. The mist separator 150 is not particularly limited, and various known mist separators can be used. The mist separator 150 can supply the compressed air increased in pressure by a pressure increasing device 130 to a first regulator 120 after removing foreign substance. In the illustrated example, the mist separator 150 is provided upstream than a second regulator 140.
The pressure gauge 160 is a device that measures a pilot supply pressure. In the illustrated example, the pressure gauge 160 is provided to the pilot pipe 104 and downstream than the second regulator 140. The pressure gauge 160 is not particularly limited, and various known pressure gauges can be used. It can be easily checked by the pressure gauge 160 whether or not the pressure increasing device 130 is functioning normally.
When the pneumatic spinning machine 1 includes the pressure gauge 160, notification may be given via a display screen 5b when a pilot supply pressure measured by the pressure gauge 160 is less than a predetermined

pressure. That is, the pneumatic spinning machine 1 may include the display screen 5b as a notification section. The notification section is not limited to the display screen 5b, and may be, for example, a lamp (not illustrated) provided in the pneumatic spinning machine 1. In this case, when the pilot supply pressure measured by the pressure gauge 160 is less than a predetermined pressure, the notification may be given by turning on or blinking the lamp. The predetermined pressure is determined in advance on the basis of, for example, a pressure required for the spinning air. In this case, the user can easily recognize an abnormality of the pressure increasing device 130 from the display screen 5b and/or the lamp. Further, when the pneumatic spinning machine 1 includes the pressure gauge 160, the pilot supply pressure may be monitored, and an optimum pilot supply pressure may be automatically proposed (displayed) via, for example, the display screen 5b.
In the present embodiment, the compressed air increased in pressure by the pressure increasing device 130 is also used as a drive source for the yarn joining cart 3, in addition to being used for acquiring the pilot supply pressure. Therefore, since the pressure increasing device 130 is not set exclusively for

acquiring the pilot supply pressure, the effect that the pilot supply pressure can be adjusted by the second regulator 140 is effective. In this regard, at least any one of the introduction pipe 101, the spinning pipe 102, the introduction branch pipe 103, the pilot pipe 104, or the yarn joining pipe 105 may be provided with a valve. Opening and closing of the valve may be appropriately controlled by, for example, the machine control device 5a.
Although the embodiment and the alternative embodiment have been described above, one aspect of the present invention is not limited to the embodiment and the alternative embodiment described above.
In the above-described embodiment and alternative embodiment, the first regulator 120 is provided at a position illustrated in FIGS. 6 and 7, but a position where the first regulator 120 is provided is not limited to the position illustrated in the drawings. The first regulator 120 may be provided, for example, near the pressure display section 5d.
In the above-described embodiment and alternative embodiment, an inner diameter of the spinning pipe 102 on the first regulator 120 side may be smaller than an inner diameter of the introduction pipe 101 on the first

regulator 120 side. This enables reduction of a pressure loss when the compressed air flows from the introduction pipe 101 via the first regulator 120 to the spinning pipe 102. However, for example, when the inner diameters of the introduction pipe 101 and the spinning pipe 102 are sufficiently large, the inner diameter of the spinning pipe 102 and the inner diameter of the introduction pipe 101 may be the same.
In the above-described embodiment and alternative embodiment, the pilot pipe 104 may be exclusively connected to the outlet side (the air tank 132) of the pressure increasing device 130. In this case, the pressure increasing device 130 can be used as a dedicated device for acquisition of the pilot supply pressure, and the pressure increasing device 130 can easily adjust the pressure of the compressed air to a pressure optimum as the pilot supply pressure. Further, in this case, the pneumatic spinning machine 1 need not include the second regulator 140.
The above-described embodiment and alternative embodiment include the introduction branch pipe 103 that branches from the introduction pipe 101 as the third pipe. However, instead of this, the pneumatic spinning machine 1 may be provided with, as a third pipe, a

separate pipe connected to the air tank 22 of the compressed air supply source 20 to distribute the compressed air. For example, apart from the introduction pipe 101, a third pipe with a relatively small flow rate may be drawn from the compressed air supply source 20, and the pressure increasing device 130 and the pilot pipe 104 (fourth pipe) may be connected to the third pipe. That is, a high-pressure line of a separate route may be drawn from the compressed air supply source 20 to the first regulator 120.
In the above-described embodiment and alternative embodiment, the outlet side (the air tank 132) of the pressure increasing device 130 may be connected with, instead of or in addition to the yarn joining pipe 105, a pipe (fifth pipe) that supplies the compressed air increased in pressure by the pressure increasing device 130 to a different device.
The above-described different device to supply the compressed air increased in pressure by the pressure increasing device 130 may be a doffing cart. The doffing cart is a work cart having a doffing device. In this case, the compressed air increased in pressure by the pressure increasing device 130 can be supplied to the doffing cart. Further, in this case, the pressure

increasing device 130 can also be used as a device for supplying the compressed air to various devices of the doffing cart, in addition to being used as a device for acquisition of the pilot supply pressure. In the doffing cart, the doffing work can be performed by using the compressed air increased in pressure by the pressure increasing device 130.
For example, the doffing cart has a cradle opener, a bobbin holding device, and a yarn catching and guiding device (suction nozzle) as devices using the compressed air. The cradle opener is a device that operates a cradle of the winding device 13 when the bobbin B is attached to the winding device 13 or when the bobbin B (package P) is removed from the winding device 13. The bobbin holding device is a device that, in order to supply a new bobbin B to the cradle of the winding device 13, chucks and supplies the bobbin B. The yarn catching and guiding device is a device that catches the yarn Y fed from the pneumatic spinning device 7 and guides the yarn Y to the new bobbin B.
The doffing cart may include at least any one of a package plate or an operating lever, as a device using the compressed air. The package plate stops inertial rotation of the package P, before the package P is

removed from the winding device 13. In an operation of discharging the removed package P to a conveyor, the package plate guides the package P to the conveyor while supporting the package P rolling on an inclined surface (not illustrated) of the pneumatic spinning machine 1. The operating lever is a device for operating a yarn removing lever provided in a case where the pneumatic spinning machine 1 includes the yarn accumulating device 11. The yarn removing lever moves in order to remove the yarn Y from a yarn hooking member of the yarn accumulating device 11 when discarding once the yarn Y wound on a yarn accumulating roller of the yarn accumulating device 11 at a start of spinning. A configuration of the doffing cart is not particularly limited, and it is sufficient that the doffing operation can be performed.
In the above-described embodiment and alternative embodiment, each spinning unit 2 may have a yarn joining device that twists yarn ends with each other by a whirling airflow. In this case, the above-described different device to be supplied with the compressed air increased in pressure by the pressure increasing device 130 may be the yarn joining device. The above-described different device to be supplied with the compressed air

increased in pressure by the pressure increasing device 130 is not particularly limited, and may be various other devices that utilize the compressed air.
In the above-described embodiment and alternative embodiment, the first regulator 120 may be an electro-pneumatic regulator. In this case, a pressure of spinning air can be adjusted automatically.
In the above-described embodiment and alternative embodiment, the second regulator 140 may be an electro-pneumatic regulator. In this case, the pilot supply pressure can be adjusted automatically.
In the above-described embodiment and alternative embodiment, the yarn accumulating device 11 of the spinning unit 2 has a function of drawing out the yarn Y from the pneumatic spinning device 7, but the yarn Y may be drawn out from the pneumatic spinning device 7 with a delivery roller and a nip roller. In a case of drawing out the yarn Y from the pneumatic spinning device 7 with the delivery roller and the nip roller, a slack tube adapted to absorb slackening of the yarn Y with suction airflow, a mechanic compensator, or the like may be provided instead of the yarn accumulating device 11.
In the above-described embodiment and alternative embodiment, each device is arranged such that a yarn Y

supplied at an upper side is wound at a lower side in a direction of a machine height. However, each device may be arranged such that the yarn Y supplied at the lower side is wound at the upper side.
In the above-described embodiment and alternative embodiment, at least one of bottom rollers in the draft device 6, and the traverse mechanism 16 are driven by power from the second end frame 5 (that is, in common with the plurality of spinning units 2). However, each section (for example, the draft device, the pneumatic spinning device, the winding device, or the like) of the spinning unit 2 may be driven independently for each spinning unit 2.
In the above-described embodiment and alternative embodiment, in the travelling direction of the yarn Y, the tension sensor 9 may be arranged upstream of the yarn monitoring device 8. The unit controller 10 may be provided for each spinning unit 2. In the spinning unit 2, the waxing device 12 and the tension sensor 9 may be omitted.
In the above-described embodiment and alternative embodiment, the pneumatic spinning machine 1 is illustrated in FIG. 1 so as to wind a cheese package P, but the pneumatic spinning machine 1 can also wind a

conical package. In a case of the conical package, slackening of the yarn Y occurs by traversing of the yarn Y, but the slackening can be absorbed with the yarn accumulating device 11. A material and a shape of each component are not limited to the above-mentioned material and shape, and various materials and shapes can be adopted.
In the spinning unit 2 in the above-described embodiment and alternative embodiment, two yarn ends are connected by the yarn joining device 3a. However, instead of this, the yarn Y from the pneumatic spinning device 7 and the yarn Y of the package P may be connected (subjected to piecing) by inserting the yarn Y from the package P into the pneumatic spinning device 7 and starting the draft operation of the draft device 6 and the spinning operation of the pneumatic spinning device 7.
In the above-described embodiment and alternative embodiment, instead of the above-described configuration, the pneumatic spinning device 7 may include a pair of air-jet nozzles that twist the fiber bundle in directions opposite from each other.
In the above-described embodiment and alternative embodiment, the first regulator 120, the pressure

increasing device 130, and the second regulator 140 are arranged in the second end frame 5 of the pneumatic spinning machine 1, but at least any one of these may be arranged outside the second end frame 5 or may be arranged on an outer surface of the second end frame 5.
To the individual configurations in the above-described embodiment and alternative embodiment, various materials and shapes can be applied without limiting to the materials and shapes described above. Each configuration in the above-described embodiment or alternative embodiment can be freely applied to each configuration in another embodiment or alternative embodiment. A part of each configuration in the above-described embodiment or alternative embodiment can be appropriately omitted without departing from the gist of one aspect of the present invention.
A spinning machine according to one aspect of the present invention includes: a spinning unit that produces a yarn and winds the yarn into a package; a first pipe that distributes compressed air supplied from a compressed air supply source; a second pipe that distributes spinning air to be supplied to the spinning unit; a first regulator that is connected to the first pipe and the second pipe and that reduces a pressure of

the compressed air supplied from the first pipe to allow the compressed air to flow out to the second pipe; a third pipe that distributes the compressed air supplied from the compressed air supply source; a pressure increasing device that is connected to the third pipe and that increases a pressure of the compressed air supplied from the third pipe; and a fourth pipe that allows the compressed air increased in pressure by the pressure increasing device to flow into a pilot port of the first regulator.
As a pressure of the compressed air flowing into the pilot port (hereinafter, also referred to as "pilot supply pressure"), a pressure of a certain value or higher is required according to a pressure of the spinning air. In this respect, in the spinning machine according to one aspect of the present invention, the compressed air from the compressed air supply source does not flow directly into the pilot port of the first regulator, but flows into the pilot port after being increased in pressure by the pressure increasing device. Therefore, the pilot supply pressure equal to or higher than a certain value can be acquired from the compressed air increased in pressure by the pressure increasing device, and the pilot supply pressure becomes less

dependent on the pressure of the compressed air supplied by the compressed air supply source. As a result, the pressure of the compressed air supplied by the compressed air supply source can be reduced.
In the spinning machine according to one aspect of the present invention, the first regulator is an external pilot regulator, and has a pilot chamber communicating with the pilot port, a diaphragm constituting a wall of the pilot chamber, and a pressure regulation spring that urges the diaphragm. In this case, a configuration that achieves the above effect can be concretely realized.
The spinning machine according to one aspect of the present invention may include a mist separator that is provided to the fourth pipe and that removes particulate substances in the compressed air flowing through the fourth pipe. Accordingly, the compressed air increased in pressure by the pressure increasing device can be supplied to the first regulator after foreign substances are removed.
The spinning machine according to one aspect of the present invention may include a pressure gauge that measures a pilot supply pressure, which is a pressure of the compressed air flowing into the pilot port. In this case, it can be easily checked by the pressure gauge

whether or not the pressure increasing device is functioning normally.
The spinning machine according to one aspect of the present invention may include a notification section that gives notification when the pilot supply pressure measured by the pressure gauge is less than a predetermined pressure. In this case, an abnormality of the pressure increasing device can be easily recognized by the notification section.
The spinning machine according to one aspect of the present invention may include a second regulator provided to the fourth pipe. The compressed air supplied from the compressed air supply source may flow through the third pipe, a pressure of the compressed air may be increased by the pressure increasing device, and the pressure-increased compressed air may flow through the fourth pipe and be reduced in pressure by the second regulator. In this case, the pilot supply pressure can be adjusted to a more appropriate pressure by the second regulator.
In the spinning machine according to one aspect of the present invention, an inner diameter of the fourth pipe on a downstream side of the second regulator may be smaller than or the same as that on an upstream side.

This can reduce a pressure loss when the compressed air flows through the fourth pipe.
In the spinning machine according to one aspect of the present invention, the fourth pipe may be exclusively connected to an outlet side of the pressure increasing device. In this case, the pressure increasing device can be used as a dedicated device for acquisition of the pilot supply pressure, and the pressure increasing device can easily adjust the pressure of the compressed air to a pressure optimum as the pilot supply pressure.
In the spinning machine according to one aspect of the present invention, the outlet side of the pressure increasing device may be connected with the fourth pipe and a fifth pipe that supplies the pressure-increased compressed air to another device. In this case, the pressure increasing device can also be used as a device for supplying the compressed air to a different device in addition to being used as a device for acquisition of the pilot supply pressure, which can simplify the configuration of the entire spinning machine. Since the number of the pressure increasing devices in the spinning machine does not increase, it is possible to avoid an increase in the cost of the spinning machine itself.
In the spinning machine according to one aspect of

the present invention, the different device may be a work cart. Accordingly, the compressed air increased in pressure by the pressure increasing device can be supplied to the work cart.
In the spinning machine according to one aspect of the present invention, the work cart may have a yarn joining device and a suction nozzle. In this case, in the work cart, yarn joining work can be performed by using the compressed air increased in pressure by the pressure increasing device.
In the spinning machine according to one aspect of the present invention, the work cart may have a doffing device. In this case, in the work cart, doffing work can be performed by using the compressed air increased in pressure by the pressure increasing device.
In the spinning machine according to one aspect of the present invention, the pressure increasing device may include a pressure increasing valve and a tank that is connected to an outlet side of the pressure increasing valve, and the fourth pipe and the fifth pipe may be connected to the tank. In this case, the pressure increasing device can stably supply the pressure-increased compressed air.
In the spinning machine according to one aspect of

the present invention, the pressure increasing device may include a pressure increasing valve and a tank that is connected to an outlet side of the pressure increasing valve. In this case, the pressure increasing device can stably supply the pressure-increased compressed air.
The spinning machine according to one aspect of the present invention may include a pressure display section that displays a pressure value of the spinning air. In this case, it can be easily checked by the pressure display section whether or not the pressure of the spinning air is normal.
In the spinning machine according to one aspect of the present invention, the spinning unit may include a spinning device having a fiber guiding section, a nozzle, and a hollow guide shaft body, and the second pipe may be connected to the nozzle. Accordingly, the spinning air can be stably supplied to the nozzle of the spinning device.
In the spinning machine according to one aspect of the present invention, an upstream side of the third pipe may be connected to the first pipe. In this case, for example, a length of the third pipe can be shortened as compared with a case where the upstream side of the third pipe is directly connected to the compressed air

supply source, and the configuration of the entire spinning machine can be made compact.
In the spinning machine according to one aspect of the present invention, the pressure increasing device may be arranged in a frame of the spinning machine. Accordingly, the pressure increasing device can be protected by the frame.
In the spinning machine according to one aspect of the present invention, the pressure increasing device may be arranged outside the frame of the spinning machine Accordingly, for example, an operator can easily access the pressure increasing device.
According to one aspect of the present invention, it is possible to provide the spinning machine capable of reducing a pressure of compressed air supplied by the compressed air supply source.

WE CLAIM
1. A spinning machine (1) comprising:
a spinning unit (2) that produces a yarn (Y) and winds the yarn (Y) into a package (P);
a first pipe (101) that distributes compressed air supplied from a compressed air supply source (20);
a second pipe (102) that distributes spinning air to be supplied to the spinning unit (2);
a first regulator (120) that is connected to the first pipe (101) and the second pipe (102) and that reduces a pressure of the compressed air supplied from the first pipe (101) to allow the compressed air to flow out to the second pipe (102);
a third pipe (103) that distributes the compressed air supplied from the compressed air supply source (20);
a pressure increasing device (130) that is connected to the third pipe (103) and that increases a pressure of the compressed air supplied from the third pipe (103); and
a fourth pipe (104) that allows the compressed air increased in pressure by the pressure increasing device (130) to flow into a pilot port (123) of the first regulator (120) .

2. The spinning machine (1) as claimed in claim
1, wherein
the first regulator (120) is an external pilot regulator, and includes:
a pilot chamber (124) communicating with the pilot port (123);
a diaphragm (DY) constituting a wall of the pilot chamber (124); and
a pressure regulation spring (126) that urges the diaphragm (DY).
3. The spinning machine (1) as claimed in claim 1 or 2, comprising a mist separator (110) that is provided to the fourth pipe (104) and that removes particulate substances in the compressed air flowing through the fourth pipe (104) .
4. The spinning machine (1) as claimed in any one of claims 1 to 3, comprising a pressure gauge (160) that measures a pilot supply pressure that is a pressure of the compressed air flowing into the pilot port (123) .
5. The spinning machine (1) as claimed in claim
4, comprising a notification section (5b) that gives

notification when the pilot supply pressure measured by the pressure gauge (160) is less than a predetermined pressure.
6. The spinning machine (1) as claimed in any one
of claims 1 to 5, comprising a second regulator (140)
provided to the fourth pipe (104), wherein
the compressed air supplied from the compressed air supply source (20) flows through the third pipe (103), the compressed air is increased in pressure by the pressure increasing device (130), and the pressure-increased compressed air flows through the fourth pipe
(104) and is reduced in pressure by the second regulator
(140) .
7. The spinning machine (1) as claimed in claim
6, wherein an inner diameter of the fourth pipe (104) on
a downstream side of the second regulator (140) is
smaller than or same as that on an upstream side.
8. The spinning machine (1) as claimed in any one
of claims 1 to 7, wherein the fourth pipe (104) is
exclusively connected to an outlet side of the pressure
increasing device (130).

9. The spinning machine (1) as claimed in any one
of claims 1 to 7, wherein the fourth pipe (104) and a
fifth pipe (105) that supplies the compressed air
increased in pressure to a different device are connected
to an outlet side of the pressure increasing device (130).
10. The spinning machine (1) as claimed in claim
9, wherein the different device is a work cart.
11. The spinning machine (1) as claimed in claim
10, wherein the work cart (3) has a yarn joining device
(3a) and a suction nozzle (3b).
12. The spinning machine (1) as claimed in claim
10 or 11, wherein the work cart has a doffing device.
13. The spinning machine (1) as claimed in any
one of claims 9 to 12, wherein
the pressure increasing device (130) includes a pressure increasing valve (131) and a tank (132) that is connected to an outlet side of the pressure increasing valve (131), and
the fourth pipe (104) and the fifth pipe (105) are

connected to the tank (132) .
14. The spinning machine (1) as claimed in any one of claims 1 to 12, wherein the pressure increasing device (130) includes a pressure increasing valve (131) and a tank (132) that is connected to an outlet side of the pressure increasing valve (131).
15. The spinning machine (1) as claimed in any one of claims 1 to 14, comprising a pressure display section (5d; 5b) that displays a pressure value of the spinning air.
16. The spinning machine (1) as claimed in any one of claims 1 to 15, wherein
the spinning unit (2) includes a spinning device (7) having a fiber guiding section (53), a nozzle (58), and a hollow guide shaft body (55), and
the second pipe (102) is connected to the nozzle (58) .
17. The spinning machine (1) as claimed in any
one of claims 1 to 16, wherein an upstream side of the
third pipe (103) is connected to the first pipe (101) .

18. The spinning machine (1) as claimed in any one of claims 1 to 17, wherein the pressure increasing device (130) is arranged in a frame (5) of the spinning machine (1).
19. The spinning machine (1) as claimed in any one of claims 1 to 17, wherein the pressure increasing device (130) is arranged outside a frame (5) of the spinning machine (1) .