Abstract: A vibration suppressing piping member suppresses vibration caused by a pulsating discharged gaseous fluid. The piping member includes a tubular portion and flange portions at both ends of the tubular portion. A bent portion is formed between the two flange portions. The two flange portions are directly connected to each other.

Abstract: A screw compressor 2 includes a compressor main body 4, a motor 8, and a gearbox 10. The compressor main body 4 includes screw rotors 5c, 5d, 6c, and 6d, rotor casings 5e and 6e accommodating therein the screw rotors 5c, 5d, 6c, and 6d, and main body casings 5a and 6a accommodating therein the rotor casings 5e and 6e, the main body casings being provided with first flanges 5b and 6b on respective ends thereof. The motor 8 drives the screw rotors 5c, 5d, 6c, and 6d via gears 10f and 10g. The gearbox 10 has an attachment surface Son which the first flange 6b to the main body casings 5a and 6a is attached, accommodates therein the gears 10f and 10g, and has a substantially rectangular shape. In a state where the compressor main body 4 is attached to the gearbox 10, a part of the first flange 6b extends to an outside of the attachment surface S, and projection regions of the rotor casings 5e and 6e onto the attachment surface S exist within the attachment surface S.

Abstract: The screw compressor includes a first-stage compressor main body and a second-stage compressor main body for compressing fluid with screw rotors, a motor for driving the first-stage compressor main body and the second-stage compressor main body, and a gear box. The gear box is connected to the first-stage compressor main body, the second-stage compressor main body, and the motor; transmits a driving force of the motor to the screw rotors, and includes a first attachment hole for attaching the first-stage compressor main body and a second attachment hole for attaching the second-stage compressor main body; and is provided with an annular rib surrounding both of the first attachment hole and the second attachment hole. In the screw compressor, the vibration of the natural vibration mode which is most burdensome and should be reduced can be efficiently reduced.

Abstract: The packaged compressor includes: an exhaust duct having an exhaust port; a gas cooler arranged to be inclined with respect to the exhaust port in the exhaust duct; and at least one sound insulating plate arranged in a direction perpendicular to the exhaust port in the exhaust duct, the sound insulating plate configured to partition the exhaust port. In the packaged compressor, the exhaust port is partitioned into divided openings by the sound insulating plate. Of the divided openings, an area of a first divided opening provided on a side where a distance between the gas cooler and the exhaust port is shortest is larger than an area of a second divided opening.

Abstract: The oil-free screw compressor includes: a screw rotor, a bearing configured to support a rotor shaft, a shaft seal device including an oil seal arranged at a position closer to the bearing and a gas seal arranged on at a position closer to the rotor chamber, an atmosphere communication space communicating with an atmosphere communication hole, and an oil return groove including a return inclined surface inclined so as to expand in diameter radially outward from a gas seal-side end to an oil seal-side end. The oil seal portion is a viscoseal including a spiral groove portion. An inner peripheral surface of the oil seal includes an inner peripheral boundary portion that defines a part of the atmosphere communication space, on a side closer to the bearing in the atmosphere communication hole. The oil seal-side end is arranged in a vicinity of the inner peripheral boundary portion and at a position closer to the bearing.

Abstract: A tubular portion; and flange portions at both ends of the tubular portion are included. A bent portion is formed between the two flange portions. The two flange portions are directly connected to each other.

Abstract: The oil-free screw compressor includes: a casing having a rotor chamber; a bearing supporting rotary shafts of screw rotors; a shaft seal device with an oil seal portion and an air seal portion; a ventilation gap positioned between the oil seal portion and the air seal portion; and an atmosphere open passage communicating an atmosphere side of the casing with the ventilation gap communicate. A most narrowed portion, an air seal portion, and oil seal portions are set such that the followings is established: (La/Sa2.5)/(Lh/Sh2.5)>|P2|/?Pb La: effective shaft seal length Sh: effective open cross-sectional area (most narrowed portion of atmosphere open passage) Lh: effective narrowed length (most narrowed portion of atmosphere open passage) Sa: shaft seal cross-sectional area |P2|: negative pressure in rotor chamber during unloading operation ?Pb: minimum differential pressure in the oil seal portion during the unloading operation.

Abstract: The packaged compressor includes: an exhaust duct having an exhaust port; a gas cooler arranged to be inclined with respect to the exhaust port in the exhaust duct; and at least one sound insulating plate arranged in a direction perpendicular to the exhaust port in the exhaust duct, the sound insulating plate configured to partition the exhaust port. In the packaged compressor, the exhaust port is partitioned into divided openings by the sound insulating plate. Of the divided openings, an area of a first divided opening provided on a side where a distance between the gas cooler and the exhaust port is shortest is larger than an area of a second divided opening.

Abstract: An oil-free screw compressor includes: a casing having a rotor chamber; a bearing supporting rotary shafts of the screw rotors; a shaft seal device including an oil seal portion and an air seal portion; an atmosphere open hole formed in the shaft seal device; at least one communication hole formed in the rotary shaft; and an annular space communicating the atmosphere open hole with the at least one communication hole communicate with each other. The annular space includes an inner peripheral annular space formed on an inner peripheral side of the casing. Assuming an open cross-sectional area of the inner peripheral annular space as S1, a total open cross-sectional area of the communication holes as S2, an open cross-sectional area of the i-th communication hole out of the communication holes as S2i, and the number of communication holes as n (n being a natural number of 1 or more), a following relationship is satisfied.

Abstract: The oil-free screw compressor includes: a screw rotor, a bearing configured to support a rotor shaft, a shaft seal device including an oil seal arranged at a position closer to the bearing and a gas seal arranged on at a position closer to the rotor chamber, an atmosphere communication space communicating with an atmosphere communication hole, and an oil return groove including a return inclined surface inclined so as to expand in diameter radially outward from a gas seal-side end to an oil seal-side end. The oil seal portion is a viscoseal including a spiral groove portion. An inner peripheral surface of the oil seal includes an inner peripheral boundary portion that defines a part of the atmosphere communication space, on a side closer to the bearing in the atmosphere communication hole. The oil seal-side end is arranged in a vicinity of the inner peripheral boundary portion and at a position closer to the bearing.

Abstract: A screw compressor 2 includes a compressor main body 4, a motor 8, and a gearbox 10. The compressor main body 4 includes screw rotors 5c, 5d, 6c, and 6d, rotor casings 5e and 6e accommodating therein the screw rotors 5c, 5d, 6c, and 6d, and main body casings 5a and 6a accommodating therein the rotor casings 5e and 6e, the main body casings being provided with first flanges 5b and 6b on respective ends thereof. The motor 8 drives the screw rotors 5c, 5d, 6c, and 6d via gears 10f and 10g. The gearbox 10 has an attachment surface Son which the first flange 6b to the main body casings 5a and 6a is attached, accommodates therein the gears 10f and 10g, and has a substantially rectangular shape. In a state where the compressor main body 4 is attached to the gearbox 10, a part of the first flange 6b extends to an outside of the attachment surface S, and projection regions of the rotor casings 5e and 6e onto the attachment surface S exist within the attachment surface S.

Abstract: The screw compressor includes a first-stage compressor main body and a second-stage compressor main body for compressing fluid with screw rotors, a motor for driving the first-stage compressor main body and the second-stage compressor main body, and a gear box. The gear box is connected to the first-stage compressor main body, the second-stage compressor main body, and the motor; transmits a driving force of the motor to the screw rotors, and includes a first attachment hole for attaching the first-stage compressor main body and a second attachment hole for attaching the second-stage compressor main body; and is provided with an annular rib surrounding both of the first attachment hole and the second attachment hole. In the screw compressor, the vibration of the natural vibration mode which is most burdensome and should be reduced can be efficiently reduced.

Abstract: An oil-free screw compressor with good assemblability of a shaft seal device that reduces leakage of a compressed gas, where the oil-free screw compressor accommodates male and female screw rotors in a rotor chamber of a casing, supports each screw rotor by a bearing through a rotor shaft, and has shaft seal devices in a shaft seal space. The shaft seal devices include an oil seal on the side of the bearing, a packing case on the side of the rotor chamber, and a gas seal. An end of the packing case on the side of the bearing and an end of the oil seal on the side of the rotor chamber are fitted and fixed by interference fit to form a gas seal accommodation space, the gas seal accommodation space accommodating the seal ring.

Abstract: An oil-free screw compressor includes: a casing having a rotor chamber; a bearing supporting rotary shafts of the screw rotors; a shaft seal device including an oil seal portion and an air seal portion; an atmosphere open hole formed in the shaft seal device; at least one communication hole formed in the rotary shaft; and an annular space communicating the atmosphere open hole with the at least one communication hole communicate with each other. The annular space includes an inner peripheral annular space formed on an inner peripheral side of the casing. Assuming an open cross-sectional area of the inner peripheral annular space as S1, a total open cross-sectional area of the communication holes as S2, an open cross-sectional area of the i-th communication hole out of the communication holes as S2i, and the number of communication holes as n (n being a natural number of 1 or more), a following relationship is satisfied.

Abstract: The oil-free screw compressor includes: a casing having a rotor chamber; a bearing supporting rotary shafts of screw rotors; a shaft seal device with an oil seal portion and an air seal portion; a ventilation gap positioned between the oil seal portion and the air seal portion; and an atmosphere open passage communicating an atmosphere side of the casing with the ventilation gap communicate. A most narrowed portion, an air seal portion, and oil seal portions are set such that the followings is established: (La/Sa2.5)/(Lh/Sh2.

Abstract: An oil-free screw compressor with good assemblability of a shaft seal device that reduces leakage of a compressed gas, where the oil-free screw compressor accommodates male and female screw rotors in a rotor chamber of a casing, supports each screw rotor by a bearing through a rotor shaft, and has shaft seal devices in a shaft seal space. The shaft seal devices include an oil seal on the side of the bearing, a packing case on the side of the rotor chamber, and a gas seal. An end of the packing case on the side of the bearing and an end of the oil seal on the side of the rotor chamber are fitted and fixed by interference fit to form a gas seal accommodation space, the gas seal accommodation space accommodating the seal ring.

Abstract: A stacking device which stacks together web members which drop down while drawing a parabolic arc, this is provided with a horizontal movement limit part which limits movement of web members in a horizontal direction, a temporary supporting unit which can take a projecting position where it projects from the horizontal movement limit part and a retracted position where it is pulled in from the projecting position and does not stick out from the horizontal movement limit part, and a receiving table which is positioned under the temporary supporting means at the projecting position and stacks the web members. The temporary supporting unit temporarily supports a web member at the projecting position and, after that, shifts to the retracted position to make the web member drop under the temporary supporting unit, so that the stacking device stacks the web members on the receiving table.

Abstract: According to the invention, there is provided a damping structure capable of obtaining a sufficient damping effect even against vibrations of small amplitudes, by promoting movements of powder/particle materials inside a hollow body. In the damping structure of the invention, a damping member 2 is provided on a structure 1 to be damped. The damping member 2 includes a hollow body 5 which is filled with powder/particle materials 3, partially leaving a space 4. A vibration wall face part 7 which vibrates more violently than the structure 1, on receiving vibration, is formed in at least a part of wall face parts 6 of the hollow body 5. The vibration wall face part 7 is preferably formed of a material having a lower elastic modulus and/or a lower density than the other parts.

Abstract: A stacking device which stacks together web members which drop down while drawing a parabolic arc, this is provided with a horizontal movement limit part which limits movement of web members in a horizontal direction, a temporary supporting unit which can take a projecting position where it projects from the horizontal movement limit part and a retracted position where it is pulled in from the projecting position and does not stick out from the horizontal movement limit part, and a receiving table which is positioned under the temporary supporting means at the projecting position and stacks the web members. The temporary supporting unit temporarily supports a web member at the projecting position and, after that, shifts to the retracted position to make the web member drop under the temporary supporting unit, so that the stacking device stacks the web members on the receiving table.

Abstract: The present invention provides a damping structure capable of obtaining a sufficient damping effect even against vibrations with small amplitudes, by promoting movements of powder/particle materials in a hollow body. In the damping structure of the invention, a damping member 2 is provided on a structure 1 to be damped. The damping member 2 is composed of a hollow body 5, a powder/particle material 3 which is filled in the hollow body 5 with partially leaving a space 4, and moves inside the hollow body 5 when the structure 1 vibrates, and a vibrator 6 which is mounted inside the hollow body 5, and relatively vibrates with respect to the hollow body 5. The vibrator 6 exerts a force by coming into contact with the powder/particle material, when vibrating.