A cylindrical pressure reducing device for insertion into a gas cylinder

Abstract

The present invention is directed to a pressure regulating device (6) for compressed gas, comprising: a body (18) with a gas inlet (20), a gas outlet (38), and a gas passage (22) fluidly interconnecting the gas inlet and the gas outlet; a valve device (24, 124) with a seat (26, 126) in the gas passage (229) and an obturator (28, 128) configured to cooperate with the seat (26, 126); a cavity (28, 128) in the body (18); and a regulator (30, 130) housed in a cavity (32, 132) and downstream of the valve device (24, 124), which together with the cavity (32, 132) defines a regulating chamber whose outer shape changes with the pressure therein and which actuates an obturator (28, 128) for regulating the flow of gas through the valve device. The body (18) is tubular over its entire extension and has a nominal outer diameter which is the largest outer diameter of the body.

Description

Technical Field

[0001] The present invention is directed to the field of delivering gases stored in a compressed state in a gas cylinder, specifically hazardous gases used in the manufacture of semiconductors.

Background Art

[0002] European Patent No. 1328756, a published prior art patent document, discloses a pressure regulating device designed to be located inside a gas cylinder. For that purpose, it is necessary to expand the collar of the gas cylinder so that the pressure regulating device can be inserted through the collar of the gas cylinder. Locating the pressure regulating device inside the gas cylinder is interesting for hazardous gases such as those used in the semiconductor industry because it protects the pressure regulating device from external actions that could cause damage.

[0003] British Patent No. 787192, a published prior art patent document, discloses a gas regulator incorporating a pressure safety valve. This gas regulator comprises a valve device and a regulator, which are arranged in a body and form a regulating chamber downstream of the valve device. This regulator comprises a bellows attached to the fixed and movable parts of the regulator, thereby forming a sealed inner chamber that functions as a spring. This regulating chamber is the space between the inner wall of the cavity in the body and the outer surface of the regulator. The fixed part of the regulator is stationary with respect to the pipe via a ball, where the position of the pipe can be adjusted by a manual handle. The ball in contact with the pipe forms a pressure safety valve for the case of an uncontrolled pressure increase at the outlet, i.e., in the regulating chamber. The regulator is further compressed and then further contracted, thereby moving the ball away from the pipe and allowing the gas to escape. The structure of this regulator is interesting in that the regulator forming a sealed inner volume achieves pressure regulation independently of atmospheric pressure. However, this structure is rather bulky and tends to exhibit undesirable pressure fluctuations when the outlet flow rate is subject to variations.

[0004] For example, in some applications, such as the semiconductor industry, the final gas consumer may be a flow regulator that operates under reduced pressure, i.e., below atmospheric pressure. Such gas flow regulators are controlled by semiconductor manufacturing machinery, which can change the flow rate from zero to the nominal value and vice versa. When such flow rate fluctuations occur, a pressure regulating device directly fluid-connected upstream of the flow regulator may exhibit undesirable fluctuations in outlet pressure to the extent that it interferes with the flow regulator, i.e., sets the flow regulator into a failure mode. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] European Patent No. 1328756 [Patent Document 2] British Patent No. 787192 [Overview of the project] [Problems that the invention aims to solve]

[0006] The present invention overcomes at least one of the shortcomings of the prior art described above to address a technical problem. More specifically, the present invention addresses the need to provide a pressure regulating device to address a technical problem. This pressure regulating device is suitable for applications where special attention must be paid to the safety and stability of the outlet pressure when the outlet flow rate fluctuates. [Means for solving the problem]

[0007] The present invention is directed toward a pressure regulating device for compressed gas, comprising: a body having a gas inlet, a gas outlet, and gas passages fluidly interconnected to the gas inlet and gas outlet; a valve device having a seat in the gas passage and a occluding device configured to cooperate with the seat; and a regulator located downstream of the valve device, housed in a cavity of the body, which together with the cavity defines a boundary with a regulating chamber having an external shape that changes with the pressure inside, and acts the occluding device to regulate the flow rate of gas through the valve device. The body is tubular along its entire length and has a nominal outer diameter which is the maximum outer diameter of the body.

[0008] According to a preferred embodiment, the body comprises a main portion having a nominal outer diameter and at least one end portion having a nominal outer diameter and attached to the main portion.

[0009] According to a preferred embodiment, at least one end portion is attached to the main portion of the body by welding.

[0010] According to a preferred embodiment, one end of the main portion houses a valve device and is provided with an annular groove around the seat portion.

[0011] According to a preferred embodiment, the body comprises a tubular wall with an inner surface that forms a cavity.

[0012] According to a preferred embodiment, the closure device comprises a poppet located upstream of the seat and configured to contact the seat, and a stem extending from the poppet through the seat and mounted on a regulator.

[0013] According to a preferred embodiment, the stem comprises a conical portion adjacent to the poppet and exhibits radial play with respect to the seat of less than 0.02 mm.

[0014] According to a preferred embodiment, the cavity comprises a bottom adjacent to the seat. The pressure regulating device comprises a compression wave spring, which is stationary at the bottom and acts on the regulator.

[0015] According to a preferred embodiment, the regulator has a shoulder-shaped end face which engages with a compression corrugated spring.

[0016] According to a preferred embodiment, the regulator comprises a movable part facing the valve device, which moves along the inner surface of the cavity and is configured to actuate the occluding device.

[0017] According to a preferred embodiment, the regulator comprises an open ring mounted around the movable part of the regulator, which is configured to contact the inner surface of the cavity.

[0018] According to a preferred embodiment, the regulator has a fixed portion on the opposite side of the valve device, which engages with a screw configured to adjust the position of the fixed portion.

[0019] According to a preferred embodiment, the screw has a conical front surface that contacts an annular recessed conical surface in the fixed portion of the adjuster, forming an engagement between the screw and the fixed portion.

[0020] According to a preferred embodiment, the engagement between the screw and the fixed portion of the adjuster is configured to center the fixed portion and allow for radial play in the cavity.

[0021] According to a preferred embodiment, the screw engages with at least one end portion via a screw-fastening mechanism.

[0022] In a preferred embodiment, the regulator includes a bellows, the first end of which is attached to a fixed portion so as to be gas-tight, and the second end of which is attached to a movable portion so as to be gas-tight, thereby forming a sealed inner volume.

[0023] In a preferred embodiment, the fixed portion and the movable portion of the regulator engage with each other so as to slide inside the bellows and be guided longitudinally.

[0024] According to a preferred embodiment, the valve device is a first valve device and the regulator is a first regulator. The pressure regulating device includes a second valve device that is fluidly continuous with a seat of a gas passage and a closure member configured to cooperate with the seat upstream of the first valve device, and a second regulator that is downstream of the second valve device, is housed in a cavity of the body, defines a boundary of an adjustment chamber having an outer shape that changes with the pressure therein together with the cavity, and operates the closure member to adjust the gas flow rate through the second valve device.

[0025] According to a preferred embodiment, the main part of the body is a first main part that houses the first valve device and the first regulator, and the body further includes a second main part that houses the second valve device and the second regulator.

[0026] According to a preferred embodiment, the pressure regulating device is configured to deliver a gas flow rate in the presence of an absolute pressure at the gas outlet that is less than 0.9 bar.

[0027] According to a preferred embodiment, the pressure regulating device further includes a port. This port is fluidly connected to a sealed chamber of the regulator via a plug and is configured to fluidly connect an external source of auxiliary gas to this sealed chamber in order to regulate the pressure of the auxiliary gas in this sealed chamber.

[0028] According to a preferred embodiment, this port leads to the outside of the body.

[0029] According to a preferred embodiment, the port indicates a main axis that is transverse to the longitudinal axis of the pressure regulating device, preferably radial to the longitudinal axis.

[0030] According to a preferred embodiment, the plug includes a threaded portion that engages with a fixed portion of the regulator and a conical needle portion that engages with an auxiliary seat formed in the fixed portion.

[0031] According to a preferred embodiment, the plug is positioned as a whole in the channel between the port and the sealed chamber of the regulator.

[0032] According to a preferred embodiment, the plug has an internal passage for an auxiliary gas between the threaded portion and the conical needle portion.

[0033] According to a preferred embodiment, the plug has an engagement surface at the opposite end of the sealed chamber of the regulator that engages with the tool by inserting the tool into the port.

[0034] According to a preferred embodiment, the engagement surface of the plug indicates the insertion direction of the tool, aligned with the port.

[0035] According to a preferred embodiment, the engagement surface of the plug is configured such that engagement with the tool is achieved by rotation, so that the rotation of the tool causes the plug to rotate.

[0036] According to a preferred embodiment, the regulator comprises a fixed portion and at least one flexible wall fitted to the fixed portion and the movable portion to be gas-tight. The sealed chamber of the regulator is bounded by the at least one flexible wall, the fixed portion, and the movable portion.

[0037] Advantageously, the occluding device is preferably fixed and mechanically connected to the movable part of the regulator.

[0038] Advantageously, at least one flexible wall is circular, bellows-shaped, and made of metal.

[0039] Advantageously, the port is located on the cylindrical outer surface of the main body. This cylindrical outer surface can be engaged with an auxiliary gas source to ensure gastightness.

[0040] The present invention is also directed to a device for a gas cylinder, which comprises: a main body with a male thread portion configured to engage with the collar of the gas cylinder, the gas inlet, the gas outlet, and the gas passage interconnecting the gas inlet to the gas outlet; a shut-off valve for the gas passage housed in the main body; and a pressure regulating device configured to be fluidly connected to the gas inlet via the male thread portion and inserted into the gas cylinder. This pressure regulating device is according to the present invention.

[0041] The present invention can also be applied to the following:

[0042] (1) A pressure regulating device for compressed gas, comprising: a body having a gas inlet, a gas outlet, and gas passages fluidly interconnected to the gas inlet and gas outlet; a valve device having a seat in the gas passage and a occluding device configured to cooperate with the seat; and a regulator housed in a cavity of the body and downstream of the valve device, which together with the cavity defines a boundary with a regulating chamber having an external shape that changes with the pressure inside, and acts a occluding device for regulating the flow rate of gas through the valve device.

[0043] (2) The pressure regulating device according to (1), comprising: a poppet located upstream of the seat and configured to contact the seat; and a stem extending from the poppet through the seat and attached to the regulator.

[0044] (3) The pressure adjustment device as described in (2), wherein the stem comprises a conical portion adjacent to the poppet and exhibits radial play with the seat of less than 0.02 mm.

[0045] (4) A pressure regulating device according to any one of (1) to (3), wherein the cavity has a bottom adjacent to the seat, and the pressure regulating device comprises a compression corrugated spring, the compression corrugated spring resting at the bottom and acting on the regulator. The corrugated spring may have at least four waveforms per rotation, each waveform forming a contact area.

[0046] (5) The pressure adjusting device described in (4), wherein the adjuster has a shoulder-shaped end face and engages with a compression corrugated spring.

[0047] (6) A pressure regulating device according to any one of (1) to (5), wherein the regulator has a movable part that faces the valve device, moves along the inner surface of the cavity and is configured to actuate the occluding device.

[0048] (7) The pressure regulating device according to (6), wherein the regulator comprises an opening ring which is mounted around the movable part of the regulator and is configured to contact the inner surface of the cavity.

[0049] (8) A pressure regulating device according to any one of (1) to (7), wherein the regulator comprises a fixed portion located on the opposite side of the valve device and engaging with a screw configured to adjust the position of the fixed portion.

[0050] (9) The pressure adjusting device according to (8), wherein the screw has a conical front surface that contacts an annular recessed conical surface in the fixed portion of the adjuster, forming an engagement between the screw and the fixed portion.

[0051] (10) The pressure regulating device according to (8) or (9), wherein the engagement between the screw and the fixed portion of the regulator is configured to center the fixed portion and allow radial play in the cavity.

[0052] (11) The screw engages with the main body in a screw-fastened manner with the pressure adjustment device described in (8) to (10).

[0053] (12) A pressure regulating device according to either (6) and (7) and any of (8) to (11), wherein the regulator comprises a bellows, the first end of which is attached to a fixed part so as to be gas-tight, and the second end of which is attached to a movable part so as to be gas-tight, thereby forming a sealed inner volume.

[0054] (13) The pressure regulating device according to (12), wherein the fixed part and the movable part of the regulator engage with each other so as to slide inside the bellows and be guided in the longitudinal direction.

[0055] The present invention can also be applied to the following:

[0056] (14) Pressure regulating device for compressed gas, comprising: a body having a gas inlet, a gas outlet, and gas passages fluidly interconnected to the gas inlet and gas outlet; a valve device having a seat in the gas passage and a occluding device configured to cooperate with the seat; and a regulator housed in a cavity of the body and downstream of the valve device, which together with the cavity defines a boundary with a regulating chamber having an external shape that changes with the pressure inside, and acts a occluding device for regulating the flow rate of gas through the valve device, wherein the body comprises a main portion and at least one end portion attached to the main portion.

[0057] (15) The pressure regulating device as described in (14), wherein at least one end portion is attached to the main body by welding.

[0058] (16) A pressure regulating device according to either (14) or (15), wherein one end of the main portion houses a valve device and has an annular groove around the seat portion.

[0059] (17) A pressure regulating device according to any one of (14) to (16), wherein the main body comprises a tubular wall with an inner surface that forms a cavity.

[0060] The present invention can also be applied to the following:

[0061] (18) A method for assembling a pressure regulating device according to any one of (14) to (17), comprising the step of welding together a main portion and at least one end portion by applying a welding arc along a circular joint between these portions.

[0062] (19) The method of (18), which includes the step of installing a cooling ring around the main body adjacent to the circular joint before welding in order to avoid overheating of the valve device.

[0063] The method according to (19), wherein the pressure regulating device described in (20)(16) is configured to have a cooling ring axially superimposed on an annular groove. [Effects of the Invention]

[0064] The present invention is particularly interesting in that it offers the advantage of miniaturization, especially in the radial direction, and the advantage of pressure stability when the outlet flow rate and / or inlet pressure change. [Brief explanation of the drawing]

[0065] [Figure 1] This is a perspective view of a device for a gas cylinder equipped with a pressure adjustment device according to the present invention. [Figure 2] This is a cross-sectional view of the pressure regulating device in the first embodiment shown in Figure 1. [Figure 3] This is a cross-sectional view of a second embodiment of the pressure regulating device shown in Figure 1. [Modes for carrying out the invention]

[0066] Figure 1 is a perspective view of a device for delivering gas from a gas cylinder.

[0067] Device 2 comprises an external part 4 and an internal part 6. The internal part is intended to be located inside the gas cylinder, while the external part 4 is intended to be located outside the gas cylinder, for example, directly on top of the gas cylinder's collar.

[0068] External unit 4 basically comprises the main body 8 of device 2, a shut-off valve 10, a gas outlet port 12, a replenishment port 16, and a replenishment valve 14. The main body 8 has a male threaded portion 8.1 designed to engage with the collar of the gas cylinder. A gas passage (not shown) is formed inside the main body 8 such that a gas inlet (not shown) formed in the male threaded portion 8.1 is fluidically interconnected to the gas outlet of the gas outlet port 12. The shut-off valve 10 is designed to be operated, for example, manually, and to selectively shut off or open the gas passage. The replenishment port 16 can be fluidly connected to a replenishment passage that extends through the male threaded portion 8.1 parallel to the gas passage and is open to the outside at the front of the male threaded portion 8.1.

[0069] The above elements are publicly known to those skilled in the art and do not need to be described in further detail.

[0070] The main body 8 also includes a port 8.2 in the male threaded portion 8.1, which is formed as a tubular portion that is mechanically integrated with the male threaded portion 8.1, for example by welding, and is fluidly connected to a second portion 6 of device 2, such as a pressure regulating device.

[0071] Figure 2 is a cross-sectional view of the pressure regulating device 6 in the device shown in Figure 1, according to a first embodiment.

[0072] The pressure regulating device 6 comprises two stages, namely a first stage 6.1 and a second stage 6.2. As is obvious, the pressure regulating device 6 comprises a body 18 which is tubular throughout its entire length and has a nominal outer diameter which is the maximum outer diameter of the body. In other words, the nominal outer diameter determines whether the pressure regulating device 6 can be inserted through the collar of the gas cylinder. If the nominal outer diameter is less than the inner diameter of the collar, it can be inserted through it; on the other hand, if the nominal outer diameter is greater than the inner diameter of the collar, it cannot be inserted through it. The body 18 comprises several parts 18.1, 18.2, 18.3, 18.4, 18.5, and 18.6, all of which are tubular with the same nominal outer diameter, arranged from end to end along the longitudinal axis, and preferably joined to each other by annular welding.

[0073] The first stage 6.1 of the pressure regulating device 6 comprises a main body portion 18.1 and two end portions 18.2 and 18.3 at each end of the main portion 18.1. End portion 18.2 forms the gas inlet 20 of the pressure regulating device 6 and the first stage 6.1. End portion 18.2 is generally cap-shaped and comprises a tubular portion 18.2.1 positioned in contact with the main portion 18.1 of the body 18, a lid portion 18.2.2, and a port 18.2.3 that forms a reduced-diameter pipe portion that forms the gas inlet 20. End portion 18.3, on the opposite side of end portion 18.2, comprises a tubular portion 18.3.1 positioned in contact with the main portion 18.1 of the body 18, and a transverse wall 18.3.2 with a hole 18.3.3 that accommodates, for example, a sintered filter and forms the gas outlet in the first stage 6.1 of the pressure regulating device 6. The gas passage 22 is provided in the assembly of the main body 18, consisting of the main portion 18.1 and the end portions 18.2 and 18.3, and interconnects the gas inlet 20 with the gas outlet in the first stage 6.1 of the pressure regulating device 6.

[0074] The valve device 24 is provided in the body 18, for example, in the main portion 18.1 of the body 18. The valve device 24 comprises a seat 26 positioned in the gas passage 22, and a closure 28 that is movable to cooperate with the seat 26. The closure 28 comprises a poppet 28.1 positioned upstream of the seat 26 to contact the seat 26 to make a gas-tight seal, and a stem 28.2 extending longitudinally from the poppet 28.1 through the seat 26 to the downstream side of the seat 26. The seat 26 may comprise a ring 26.1, which is made of a non-metallic material and has an inner conical surface that is in contact with the poppet 28.1 of the closure 28. This ring is housed in a corresponding cavity formed in the main portion 18.1 of the body 18. For example, an O-ring gasket 26.2 can be provided in the cavity between the ring 26.1 and the circular groove of the cavity to provide a gas-tight barrier between the ring 26.1 and the main portion 18.1 of the body 18. A snap ring 26.3 can be provided in the cavity to hold the ring 26.1.

[0075] The regulator 30 is located in a cavity 32 in the main portion 18.1 of the body 18. This cavity is immediately downstream of the valve device 24 and forms part of the gas passage 22. The cavity 32 is cylindrical and its radial boundary is defined by the inner surface of the cylindrical wall in the main portion 18.1 of the body 18. The occluding device 28 of the valve device 24 is fitted to the regulator 30 and, together with the cavity, defines the boundary of the regulating chamber, which has an external shape that changes with the pressure inside. The regulator 30 ensures that a sealed chamber is formed and can be further contracted longitudinally until the pressure inside the regulating chamber increases. The sealed chamber is filled with gas to provide a restorative reaction force when the regulator 30 is compressed.

[0076] More specifically, the regulator 30 comprises a fixed portion 30.1, a movable portion 30.2, and a bellows 30.3 that interconnects the fixed and movable portions. The bellows 30.3 is attached to the fixed portion 30.1 at one end and to the movable portion 30.2 at the opposite end. These two attachments are, for example, gas-sealed by welding, and the bellows is made of metal. As is obvious, the fixed portion and the movable portions 30.1 and 30.2 engage with each other so that they can slide along their longitudinal axes. For this purpose, for example, the fixed portion 30.1 comprises a spindle portion 30.1.1, which engages with the inside of the cylindrical wall 30.2.1 of the movable portion 30.2 so that it can slide. More specifically, the spindle portion 30.1.1 has an outer circular groove, which holds a sliding ring 30.1.2 that exhibits a low coefficient of friction at the contact point with the cylindrical wall 30.2.1. This contact area does not need to be gas-tight. The cylindrical wall 30.2.1 can provide at least one aperture 30.2.2 for providing gas communication between the inner and outer volumes, thereby preventing the pressure difference between these two volumes from increasing during the operation of the regulator 30. Failure to do so would impede the proper functioning of the regulator 30. As is obvious, a compression spring 30.4 can be provided in the inner volume, i.e., between the fixed portion 30.1 and the movable portion 30.2, thereby providing an additional repulsive force to the repulsive force applied by the gas contained in the sealed chamber (essentially corresponding to the sum of the inner and outer volumes described above). The presence of the compression spring 30.4 can depend on a desired pressure difference between the inlet and outlet during operation.

[0077] The fixed portion 30.1 of the regulator may provide a channel 30.1.3 for filling a sealed chamber with an appropriate amount of gas and / or for regulating the amount of gas. For example, the channel 30.1.3 is closed by a ball 30.1.4. The ball 30.1.4 is pressed into the channel, which advantageously has a tapered inner diameter. The ball 30.1.4 can be replaced by a check valve. Alternatively, the channel 30.1.3 may be omitted. This means that once the bellows 30.3 is fitted to the fixed portion 30.1 and the movable portion 30.2 respectively, the chamber will be reliably closed.

[0078] The movable portion 30.2 of the regulator 30 has an internal thread 30.2.3 on its front surface facing the valve device 24, which receives the threaded end of the corresponding stem 28.2 of the occluding device 28. The occluding device 28 is then firmly attached to the movable portion 30.2 of the regulator 30.

[0079] A compression spring 34 can be provided between the bottom of the cavity 32 adjacent to the seat portion 26 and the movable portion 30.2 of the regulator 30. The compression spring 34 acts against the repulsive force of the gas in the sealed chamber of the regulator and the repulsive force of an optional compression spring 30.4 housed in the regulator 30. The compression spring 34 is advantageously a corrugated spring, also commonly known as a Smalley® spring. A corrugated spring is a spring made from flat wire before hardening by a process called on-edge coiling. The compression spring 34 is advantageously a multi-turn corrugated spring with optionally wedge-shaped ends. The number of turns is at least two, preferably at least three. The number of waves, i.e., the contact areas per turn, is at least four, preferably at least five, and more preferably at least six. In this embodiment, the number of turns is three. Such a spring is particularly interesting and useful in this configuration because it ensures that the repulsive force applied to the regulator 30, for example, its movable part 30.2, is distributed fairly evenly to the surrounding area. This is especially useful in this case because the movable part 30.2 of the regulator 30 is not precisely guided radially into the cavity 32. Using a conventional compression spring would inevitably lead to an imbalance in the load distribution around the longitudinal axis, which tends to move the movable part 30.2 and the closure 28 radially, potentially impairing good performance and accuracy in gas pressure adjustment.

[0080] The regulator 30 may include an induction release ring 30.5 mounted on a movable part 30.2, for example, in an outer circular groove formed on this movable part. The induction ring 30.5 is open to allow gas to flow along the adjustment chamber, which is bounded by the cavity 32 and the regulator 30, to the outlet. The induction release ring 30.5 has an outer diameter less than the inner diameter of the cavity 32, thereby avoiding permanent contact and undesirable frictional forces that would hinder proper and precise adjustment. The purpose of the induction release ring 30.5 is to absorb any possible radial movement of the regulator in the event of impactful operation of the pressure adjustment device 6.

[0081] As is evident, the movable part 30.2 can have a shoulder-shaped front surface 30.2.4 facing the valve device 24 in order to receive the compression spring 34.

[0082] The fixed portion 30.1 of the regulator is held in place axially and radially by a screw 36 alone. The screw 36 screw-engages with the transverse wall 18.3.2 of the end portion 18.3 of the main body 18. It has a conical front surface that contacts the annular recessed conical surface of the fixed portion 30.1 of the regulator 30. As is obvious, the fixed portion 30.1 has an outer diameter less than the corresponding inner diameter of the cavity 32, thereby forming an annular section for the gas passage 22 to the outlet. The screw 36 is an adjustment screw in that it not only allows the fixed portion 30.1 of the regulator 30 to be positioned and centered, but also allows for its adjustment before compression and thereby adjustment of the outlet pressure.

[0083] The second stage 6.2 of the pressure regulating device 6 is similar to the first stage 6.1 of the pressure regulating device 6. It differs fundamentally only in the structure of the body 18 and the valve device 124. The reference numbers of the first stage are used to specify the same or corresponding internal elements in the second stage, but with 100 added to these numbers. See the description of these elements related to the first stage.

[0084] The body of the second stage 6.2 comprises a main section 18.4 housing a valve device 124, a regulator 130, and a compression spring 134, and two end sections 18.5 and 18.6. In contrast to the first stage, the two end sections 18.5 and 18.6 of the body 18 are positioned end to end relative to the downstream end of the main section 18.4, i.e., on the opposite side of the first stage 6.1. The main section 18.4 of the second stage 6.2 is similar to the main section 18.1 of the first stage 6.1. The end section 18.5 is similar to the end section 18.3 of the first stage 6.1. In other words, the end portion 18.5 comprises a tubular portion 18.5.1 positioned in contact with the main portion 18.4 of the body 18, and a transverse wall 18.5.2 with an orifice 18.5.3 that houses, for example, a sintered filter and forms a gas outlet for a second stage 6.2, which is, for example, a gas outlet 38 of a pressure regulating device 6.

[0085] The end portion 18.6 forms the gas outlet 38 of the pressure regulating device 6 and the second stage 6.2. The end portion 18.6 is generally cap-shaped and comprises a tubular portion 18.6.1 positioned in contact with the end portion 18.5 of the main body 18, a lid portion 18.6.2, and a port 18.6.3 that forms a reduced-diameter pipe portion that forms the gas outlet 38.

[0086] Valve device 124 differs somewhat from the first valve device 24 of 6.1 in that its seat 126 is formed of a metallic material and is integrated with, for example, the main portion 18.4 of the body 18, while the occluder 128 supports a gasket 128.3 made of elastomer material, such as an O-ring, which is held in contact with the poppet 128.1 by, for example, a sleeve 128.4. The stem 128.2 of the occluder 128 has a circular outer groove that receives the gasket 128.3 at a position directly adjacent to the poppet 128.1. The sleeve slides along the stem 128.2 and has an inner circular surface that contacts the outer circular portion of the gasket and an inner large bore fixed to the outer surface of the poppet 128.1. The gasket 128.3 is thus trapped between the circular outer groove of the stem 128.2 and the corresponding inner circular surface of the sleeve 128.4. The corresponding inner circular surface of the sleeve 128.4 also shows a front surface facing the seat 126, which can contact the seat 126 when the gasket is deformed to a given level.

[0087] Valve device 124 differs from valve device 24 of the first stage 6.1 in that the stem 128.2 exhibits a cylindrical portion 128.2.1 adjacent to the poppet 128.1, and exhibits a reduced radial play of, for example, less than 0.02 mm in the gas passage through the seat 126. The radial play is the difference between the radius of the gas passage through the seat 126 and the radius of the conical portion 128.2.1 of the stem 128.2, and this difference is minimized in the axial position when centered. Advantageously, the radial play can be 0.01 mm or less.

[0088] Another difference between the second stage 6.2 and the first stage 6.1 of the pressure regulating device 6 is the absence of a compression spring inside the regulator 130.

[0089] The above-mentioned difference between the second stage 6.2 and the first stage is that the second stage 6.2 operates at a lower pressure than the first stage. More specifically, the elastomer material included in the contact portion with the seat in the valve device 124 can achieve gas airtight contact with reduced force, thereby enabling higher sensitivity and stability to pressure fluctuations in the outlet flow rate. In particular, the final consumption in the field of ion implantation in semiconductor manufacturing may include a flow regulator to which the outlet of the device is connected. Depending on various parameters in the manufacturing process, the regulator changes the gas flow rate, which means that the pressure regulating device needs to respond quickly and controllly to these fluctuations. If the pressure at the outlet of the pressure regulating device deviates by a given amount from the nominal pressure, it may cause the flow regulator to fail, even for a short period of time, resulting in a cessation of production. The above-mentioned structure of the valve device is specifically adapted to respond quickly and appropriately to flow rate fluctuations at the outlet.

[0090] Additionally, the conical portion 128.2.1 of the stem 128.2 further increases stability in the second stage as described above, because it keeps the occluder 128 and the movable portion 130.2 of the regulator in a central position, and at the same time provides a gas branching passage, particularly immediately downstream of the seat 126 and the gasket 128.3 in contact with this seat. This branching passage provides stability in the regulating chamber (bounded between the cavity 132 and the regulator 130) by converting most of the gas velocity into static pressure.

[0091] The assembly of the pressure regulating device 6 is as follows:

[0092] Regulators 30 and 130 are pre-assembled, including welding the bellows to the fixed and movable parts of the regulators, respectively. A check valve or any equivalent can be provided on the fixed part of the regulator to fill / regulate the amount of gas contained in the sealed chamber. Furthermore, various elements such as the main body parts 18.1-18.6 and the elements of valve devices 24 and 124 are manufactured prior to assembly.

[0093] The first stage 6.1 is assembled by attaching the valve device 24 to the inlet end of the main body 18.1 and inserting the regulator 30 through the outlet end of the main body 18.1. Next, the stem 28.2 of the occluding device 28 can be screwed to the regulator 30 for assembly.

[0094] Subsequently, the end portion 18.2 forming the inlet 20 is assembled to the main portion 18.1, for example, by annular welding of the joint between the tubular portions. Similarly, the end portion 18.3 forming the outlet of the first stage 6.1, equipped by screws 36, is assembled to the main portion 18.1, for example, by annular welding of the joint between the tubular portions. These two operations can be performed one or in any other order.

[0095] The first stage 6.1 is then adjusted by acting on screw 36. Special equipment may be required to connect the exit of the first stage 6.1 and, at the same time, act on screw 36.

[0096] The second stage 6.2 can be assembled similarly to the first stage 6.1, simultaneously with it, that is, independently of the first stage, so that both stages can then be assembled together. Alternatively, the second stage 6.2 can be assembled with the first stage 6.1, that is, the main part 18.4 of the body 4, equipped with the valve device 124 and regulator 130, can be assembled, and then the end parts 18.5 and 18.6 of the body 18 can be assembled in succession.

[0097] The annular welding operation described above can be performed using a rotary tool. This rotary tool is mounted around the body 18 and is configured to guide the welding head to the outer circumference around the joint between the two body parts to be assembled. The welding head is designed to generate an electric arc using the body. Referring to the assembly procedure described above, the body parts are assembled together by annular welding. Meanwhile, the valve device and regulator are already attached to the main parts 18.1 and 18.4 of the body 18. Therefore, it may be appropriate to provide special cooling to the body 18 during the welding operation, in particular to protect non-metallic elements, namely the seat 26.1, and the gasket 26.2 in the valve device 24 of the first stage 6.1, and the gasket 128.3 in the valve device 124 of the second stage 6.2. For this purpose, the cooling ring 40, schematicly shown in Figure 2, can be slid around the main portion 18.4 or 18.1 of the body 18, more specifically at the height of the valve device 124 or 24, to protect the valve device from the heat generated during welding.

[0098] As is evident in Figure 2, each of the main portions 18.1 and 18.4 of the body 18 has a circular groove 18.1.1 or 18.4.1 formed around the valve device 24 or 124 at its inlet end. Each of these grooves 18.1.1 or 18.4.1 extends longitudinally beyond the height or level of the non-metallic element of the valve device, thereby allowing heat generated at the adjacent joint of the adjacent end portion 18.2 or 18,3 to be radially transferred to the central portion 18.1.2 or 18.1.2 that houses the non-metallic element.

[0099] Figure 3 is a cross-sectional view of a second embodiment of the pressure regulating device of Figure 1. The reference numbers in the first embodiment in Figure 2 are used to specify the same or corresponding elements, with 200 added to these reference numbers. A description of these elements related to Figure 2 is referenced. Specific reference numbers are used to specify specific elements.

[0100] The pressure regulating device 206 in Figure 3 differs from the pressure regulating device 6 in Figure 2 in the structure of the regulators 230 and 330. Instead of having a sealed chamber pre-filled with a fixed predetermined amount of gas and preferably securely closed by a plug such as ball 30.1.4 in the first stage 6.1 of Figure 2, the regulators 230 and 330 are sealed by plugs 230.1.4 and 330.1.4 located in channels 230.1.3 and 330.1.3 that are operable and extend transversely, preferably radially, to the outside of ports 240 and 340, respectively. Each of ports 240 and 340 can be connected to an external source 244 of auxiliary gas to regulate the pressure in the chamber of the regulator 230 or 330, while the corresponding plug 230.1.4 or 330.1.4 is operated via an engaging tool 246 to open the corresponding channel 230.1.3 or 330.1.3. Once the desired pressure is reached, the corresponding plug 230.1.4 or 330.1.4 is then operated to close the corresponding channel 230.1.3 or 330.1.3. The auxiliary gas external source can then be disconnected from the corresponding port 240 or 340.

[0101] The above adjustment solution essentially replaces the screws 36 and 136 in the first embodiment of Figure 2, and adjusts the position of the fixed portions 30.1 and 130.1 of the adjusters 30 and 130.

[0102] The fixed portions 230.1 and 330.1 of the regulators 230 and 330 are firmly fixed to the main body 218 and are formed directly, for example, on the main body portions 218.2 and 218.4. However, the fixed portions of the regulators can be separate from the main body 218.

[0103] For example, plug 230.1.4 or 330.1.4 is located overall in channel 230.1.3 or 330.1.3 between the chamber of regulator 230 or 330 and port 238 or 338. This means that during pressure regulation by the auxiliary gas external source 244 and the engaging tool 246, the engaging tool 246 will come into contact with the auxiliary gas during regulation, and therefore needs to be gas-tightly connected to the auxiliary gas passage 244.1 of the external source 244, which is fluidly connected to port 240 or 340. The rotating gas-tight connection between the engaging tool 246 and the body of the external source 244 can be achieved by one or more gaskets or sealing parts mounted around the cylindrical surface portion of the tool, allowing a combination of translational and rotational motion of the tool while providing a gas-tight seal.

[0104] The plug 230.1.4 or 330.1.4 comprises an outer threaded portion 230.1.4.1 or 330.1.4.1 that engages with a corresponding inner thread formed in the channel 230.1.3 or 330.1.3, an auxiliary seat formed in the channel 230.1.3 or 330.1.3 that is advantageously cylindrical and interconnects with the chamber and port 240 or 340, and a needle portion 230.1.4.2 or 330.1.4.2 configured to engage in a gas-tight manner. Plug 230.1.4 or 330.1.4 further comprises an engagement surface 230.1.4.3 or 330.1.4.3 at the opposite end of the needle portion 230.1.4.2 or 330.1.4.2, and engages with the engagement tool 246 by inserting the engagement tool 246 into the port 240 or 340. Plug 230.1.4 or 330.1.4 may further comprise an internal passage 230.1.4.4 or 330.1.4.4 for auxiliary gas between the threaded portion 230.1.4.1 or 330.1.4.1 and the conical needle portion 230.1.4.2 or 330.1.4.2.

[0105] Alternatively, the plug 230.1.4.1 or 330.1.4.1 may be partially located in the channel 230.1.3 or 330.1.3 between the chamber of the regulator 230 or 330 and the port 240 or 340. More specifically, the engaging surface 230.1.4.3 or 330.1.4.3 can be fluidly positioned outside the channel 230.1.3 or 330.1.3, thereby allowing the plug 230.1.4.1 or 330.1.4.1 to be connected to the fixed portion 230.1 or 330.1, or to a second or fourth body portion 218.2 or 218.4 forming the channel 230.1.3 or 330.1.3 in a gas-hermetically sealed manner. In such a configuration, the tool 244 does not need to be gas-hermetically connected to the body of the auxiliary gas external source 242.

[0106] A protective cap 242 or 342 may be provided on the port 240 or 340 to close the port and prevent dust or foreign matter from entering the channel 230.1.3 or 330.1.3. The protective cap 242 or 342 may be made of a plastic material or a similar material that is more flexible than the metal material of the body 218.

[0107] As is evident in Figure 3, a filter 248 can be provided at the gas inlet 220, which is formed, for example, in the first body portion 218.1. A filter 248 can also be provided in the gas passage 222 between two stages 206.1 and 206.2, for example, in the second body portion 218.2. A filter 248 can also be provided at, or near, the gas outlet 238 of, for example, the fourth body portion 218.4. The filter 248 can be made of frit material and press-fitted into the corresponding body portion.

[0108] The aforementioned pressure regulator 206 is particularly advantageous in that its regulators 230 and 330 can be easily controlled and adjusted not only when the regulators are stationary, i.e., when there is no gas flow, but also when they are in a dynamic state, i.e., when a gas flow is being output.

[0109] As is evident, the body 218 may have an outer circular ring 218.1.1 on its outer surface adjacent to the gas inlet 220, such as the first body portion 218.1, which is designed to engage with a dynamic adjustment tool, which can press the tool against the body 218 at the gas inlet 220 and seal-engage with the gas inlet.

[0110] The pressure regulating devices 6 and 206 described above can be configured to operate under reduced pressure conditions, which means that at least one of stages 6.1 or 206.1 and 6.2 or 206.2 must be properly closed at atmospheric pressure, i.e., about 1 bar, and that the absolute pressure at the outlet must be less than 1 bar, e.g., less than 0.9 bar, in order to open the closed stage and allow the gas to be delivered.

[0111] The pressure regulating devices 6 and 206 described above can also be configured to operate by opening and closing the gas passages normally under conditions greater than atmospheric pressure, i.e., when the outlet pressure reaches an upper limit of more than 1 bar.

[0112] The nominal outer diameter of the pressure regulating device 6 described above can be less than 25 mm, allowing it to be inserted into most collars in commercially available gas cylinders.

[0113] The pressure regulating device 6 described above can be a single-stage device instead of a dual-stage device.

[0114] The pressure regulating devices 6 and 206 described above can be external, i.e., designed to be located outside the gas cylinder, instead of being internal, i.e., designed to be located inside the gas cylinder.

Claims

1. A pressure regulating device (6,206) for compressed gas, A main body (18, 218) having gas inlets (20, 220), gas outlets (38, 238), and gas passages (22, 222) that fluidly interconnect the gas inlets and gas outlets, A valve device (24, 124, 224, 324) comprising seat portions (26, 126, 226, 326) in the gas passage (22, 222), and a closure device (28, 128, 228, 328) configured to cooperate with the seat portions (26, 126, 226, 326), Downstream of the valve devices (24, 124, 224, 324), a regulator (30, 130, 2320, 330) is housed in the cavities (32, 132, 232, 332) of the main body (18, 218), and together with the cavities (32, 132, 232, 332), it defines the boundary of a regulating chamber with an external shape that changes according to the pressure inside, and acts the occluding devices (28, 128, 228, 328) to adjust the gas flow rate through the valve devices. Equipped with, The shape of the adjustment chamber is changeable because it is configured so that the adjusters (30, 130, 2320, 330) can be retracted. The regulators (30, 130, 2320, 330) are fitted with the closure devices (28, 128, 228, 328), Herein, the pressure regulating device (6, 206) is characterized in that the main body (18, 218) is tubular along its entire length and has a nominal outer diameter along the regulator (30, 130, 2320, 330) and the valve device (24, 124, 224, 324), which is the maximum outer diameter of the main body.

2. The pressure regulating device (6, 206) according to claim 1, wherein the main body (18, 218) comprises a main portion (18.1, 18.4, 218.1, 218.3) having a nominal outer diameter, and at least one end portion (18.2, 18.3, 18.5, 18.6, 218.2, 218.4, 218.5) having a nominal outer diameter and attached to the main portion (18.1, 18.4, 218.1, 218.3).

3. The pressure regulating device (6, 206) according to claim 2, wherein at least one of the end portions (18.2, 18.3, 18.5, 18.6, 218.2, 218.4, 218.5) is attached to the main portion (18.1, 18.4, 218.1, 218.3) of the body (18, 218) by welding.

4. The pressure regulating device (6) according to claim 2 or 3, wherein one end of the main portion (18.1, 18.4) houses the valve device (24, 124) and has an annular groove (18.1.1, 18.4.1) around the seat portion (26, 126).

5. The pressure regulating device (6, 206) according to any one of claims 1 to 4, wherein the main body (18, 218) comprises a tubular wall having an inner surface that forms the cavity (32, 132, 232, 332).

6. The pressure regulating device (6, 206) according to any one of claims 1 to 5, wherein the occluding member (28, 128, 228, 328) comprises a poppet (28.1, 128.1) positioned upstream of the seat portion (26, 126, 226, 326) and configured to contact the seat portion, and a stem (28.2, 128.2) extending from the poppet (28.1, 128.1) through the seat portion (26, 126, 226, 326), the stem being mounted on the regulator (30, 130).

7. The pressure regulating device (6, 206) according to claim 6, wherein the stem (128.2) comprises a conical portion (128.2.1) adjacent to the poppet (128.1) and exhibits radial play of less than 0.02 mm with respect to the seat portion (126).

8. The pressure regulating device (6, 206) according to any one of claims 1 to 7, wherein the cavity (32, 132, 332) has a bottom adjacent to the seat portion (26, 126, 326), the pressure regulating device comprises a compression wave spring (34, 134, 334), the compression wave spring (34, 134, 334) rests at the bottom and acts on the regulator (30, 130, 330).

9. The pressure adjustment device (6, 206) according to claim 8, wherein the regulator (30, 130, 330) comprises shoulder-shaped end faces (30.2.4, 130.2.4) that engage with the compression corrugated springs (34, 134, 334).

10. The pressure regulating device (6, 206) according to any one of claims 1 to 9, wherein the regulator (30, 130, 230, 330) comprises movable parts (30.2, 130.2, 230.2, 330.2), the movable parts facing the valve devices (24, 124, 224, 324) and configured to move along the inner surface of the cavities (32, 132, 232, 332) and to actuate the occluders (28, 128, 228, 328).

11. The pressure regulating device (6) according to claim 10, wherein the regulator (30, 130) comprises an opening ring (30.5, 130.5), the opening ring (30.5, 130.5) is mounted around the movable part (30.2, 130.2) of the regulator and is configured to contact the inner surface of the cavity (32, 132).

12. The pressure regulating device (6) according to any one of claims 1 to 11, wherein the regulator (30, 130) comprises a fixed portion (30.1, 130.1), the fixed portion (30.1, 130.1) is located on the opposite side of the valve device (24, 124) and engages with a screw (36, 136) configured to adjust the position of the fixed portion.

13. The pressure adjustment device (6) according to claim 12, wherein the screw (36, 136) has a conical front surface that contacts an annular recessed conical surface on the fixing portion (30.1, 130.1) of the regulator (30, 130), and forms an engagement portion between the screw and the fixing portion.

14. The engagement between the screws (36, 136) and the fixing portion (30.1, 130.1) of the regulator (30, 130) is such that the fixing portion is centered and there is radial play in the cavity (32, 132), as described in claim 12 or 13 (6).

15. The screw (36, 136) screw-engages with at least one of the end portions (18.3, 18.5) of the main body (18), the pressure regulating device (6) according to any one of claims 12 to 14 as dependent on claim 2.

16. The pressure regulating device (6) according to any one of claims 12 to 15 as dependent on claim 10, wherein the regulator (30, 130) comprises bellows (30.3, 130.3), the first end of which is attached to the fixed portion (30.1, 130.1) so as to be gas-tight, and the second end of which is attached to the movable portion (30.2, 130.2) so as to be gas-tight, thereby forming a sealed inner chamber.

17. The pressure adjustment device (6) according to claim 16, wherein the fixed portion (30.1, 130.1) and the movable portion (30.2, 130.2) of the regulator (30, 130) engage with each other so as to slide and be guided longitudinally inside the bellows (30.3, 130.3).

18. The valve device is a first valve device (24, 224), the regulator is a first regulator (30, 320), and the pressure regulating device is a second valve device (124, 324) which is fluidly continuous downstream of the first valve device (24, 224) and includes seats (126, 326) of the gas passage (22, 222), and occluding devices (128, 328) configured to cooperate with the seats (126, 326), and the second valve device (124, 324) A pressure regulating device (6, 206) according to any one of claims 1 to 17, further comprising: a second regulator (130, 330) housed downstream in a cavity (132, 332) of the main body (18, 218), which together with the cavity (132, 332) defines the boundary of a regulating chamber having an external shape that changes with the pressure inside the regulating chamber, and which acts the occluding device (128, 328) to regulate the gas flow rate through the second valve device (124, 324).

19. The main body is a first main body (18.1, 218.1) housing the first valve device (24, 224) and the first regulator (30, 230), and the main body further comprises a second main body (18.4, 218.3) housing the second valve device (124, 324) and the second regulator (130, 330), as described in claim 18, when dependent on claim 2.

20. A pressure regulating device according to any one of claims 1 to 19 (6, 206), configured to deliver a gas flow rate in the presence of an absolute pressure at the gas outlet that is less than 0.9 bar.

21. A pressure regulating device (206) according to any one of claims 1 to 19, further comprising a port (240, 340) which is fluidly connected to a sealed chamber of the regulator (230, 330) via a plug (230.1.4, 330.1.4) and configured to fluidly connect an external source of auxiliary gas (244) to the sealed chamber for regulating the pressure of the auxiliary gas in the sealed chamber.

22. The pressure regulating device (206) according to claim 21, wherein the ports (240, 340) lead to the outside of the main body (218).

23. The pressure regulating device (206) according to claim 21 or 22, wherein the ports (240, 340) indicate a principal axis transverse to the longitudinal axis of the pressure regulating device, preferably radial to the longitudinal axis.

24. The pressure regulating device (206) according to any one of claims 21 to 23, wherein the plug (230.1.4, 330.1.4) comprises a threaded portion (230.1.4.1, 330.1.4.1) that engages with a fixed portion (230.1, 330.1) of the regulator (230, 330) and a conical needle portion (230.1.4.2, 330.1.4.2) that engages with an auxiliary seat formed on the fixed portion.

25. The plugs (230.1.4, 330.1.4) are generally located in the channels (230.1.3, 330.3.1) between the ports (240, 340) and the sealed chambers of the regulators (230, 330). A pressure regulating device (206) according to any one of claims 21 to 24.

26. The pressure regulating device (206) according to claim 25, as dependent on claim 24, wherein the plug (230.1.4, 330.1.4) comprises an internal passage (230.1.4.4, 330.1.4.4) for the auxiliary gas between the threaded portion (230.1.4.1, 330.1.4.1) and the conical needle portion (230.1.4.2, 330.1.4.2).

27. The pressure regulating device (206) according to claim 25 or 26, wherein the plug (230.1.4, 330.1.4) comprises an engaging surface (230.1.4.3, 330.1.4.3) at the opposite end of the sealed chamber of the regulator (230, 330) for engaging with the tool (246) by inserting the tool (246) into the port (230.1.4, 330.1.4).

28. The pressure regulating device (206) according to claim 27, wherein the engaging surfaces (230.1.4.3, 330.1.4.3) of the plug (230.1.4, 330.1.4) indicate the insertion direction of the tool (246) aligned with the port (240, 340).

29. The pressure regulating device (206) according to claim 27 or 28, wherein the engaging surfaces (230.1.4.3, 330.1.4.3) of the plug (230.1.4, 330.1.4) are configured to engage with the tool (246) by rotation, such that the rotation of the tool (246) causes the plug (230.1.4, 330.1.4) to rotate.

30. The regulator (230, 330) comprises a fixed portion (230.1, 330.1), a movable portion (230.2, 330.2), and at least one flexible wall (230.3, 330.3) fitted to the fixed portion (230.1, 330.1) and the movable portion (230.2, 330.2) in a gas-tight manner, wherein the sealed chamber of the regulator (230, 330) is defined by at least one flexible wall (230.3, 330.3), the fixed portion (230.1, 330.1), and the movable portion (230.2, 330.2), the pressure regulating device (206) according to any one of claims 21 to 29.

31. A device (2) for a gas cylinder, A main body (8) having a male threaded portion (8.1), a gas inlet, a gas outlet (12) of the male threaded portion, and a gas passage connecting the gas inlet to the gas outlet, configured to engage with the collar of the gas cylinder, The main body (8) houses a shut-off valve (10) for the gas passage, A pressure regulating device (6, 206) is configured to be fluidly connected to the gas inlet at the male threaded portion (8.1) and inserted into the gas cylinder, Equipped with, Herein, the device (2) is characterized in that the pressure regulating device (6, 206) is one of the claims 1 to 30.

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