JP2023543629A - Valve plate with free microbeads - Google Patents

Abstract

The valve plate (1) with free microbeads allows the fluid (2) to flow from the upstream volume (3) to the downstream volume (4) but not in the opposite direction and allows the fluid (2) to flow from the upstream volume (3) to the downstream volume (4) but not in the opposite direction. A flow plate (5) penetrated by a flow port (6) terminated by a bead seat (7) and a permeable guide tray (9) parallel to the plate (5) sealing the port (8). pierced by a cylindrical guide port (10) containing microbeads (8) which rest on a seat (7) or on a permeable microbead end stop (11); a permeable guide tray (9) and a spacer (12) positioned between the tray (9) and the plate (5), while the evacuation passageway (13) guides the tray (9). , allowing the fluid (2) to flow when the microbeads (8) are not resting on the seats (7).

Description

The present invention relates to a valve plate with free micro-balls, which valve plate can be used mainly to control any cylinder of any reciprocating compressor or any reciprocating pump, whether said compressor or said pump is of piston type, It is intended to allow filling and/or emptying, whether of the diaphragm type or any type of volume varying device known to those skilled in the art.

There are many types of compressor valves or so-called "passive" pump valves, i.e. their opening and closing are controlled by the pressure difference between the upstream and downstream volumes they interpose. Passive valves are therefore to be distinguished from so-called "pilot" valves, the opening and closing of which is actuated by an actuator.

Passive compressor valves may be of the lamellar, plate or concentric segment type, in particular. Passive compressor valves can also take the form of "poppet valves" such as those manufactured by the company "Burckhardt", each consisting of microvalves cooperating with a return spring.

It should also be noted that the "Magnum(TM) HammerHead(TM) valve", by the company "Dresser-Rand", is specially adapted for compressors of heavy molecules such as carbon dioxide, ethylene, propane or natural gas. This is a commercially available "poppet valve."

Passive compressor valves can be metallic or non-metallic. For example, the company "Hoerbiger" manufactures valves in "PEEK", also called "polyetheretherketone", a material that provides particularly advantageous anti-wear properties.

The optimum performance of the inlet and outlet valves of piston compressors according to the state of the art is usually found at a given compressor rotational speed.

In fact, the valve constitutes a mass-spring assembly with a natural frequency. Accordingly, the valves are designed to operate under relatively precise speed or uniform load conditions of the compressor in which they are equipped.

In fact, if the compressor operates at a speed that is too far from the optimum speed of the passive valves that make up the compressor, the energy efficiency of the valves is reduced and their durability is also reduced.

In terms of energy, passive valves provide the compressor equipped with them with the best possible permeability in order to provide the best possible volumetric efficiency, i.e. the best tendency to fill and empty its cylinders. expected to have.

The high permeability of the valves limits energy losses due to pumping compressors equipped with them. This applies both to the valve located at the inlet of the compressor and to the valve located at the outlet of the compressor.

To serve this purpose, passive compressor valves must open from the minimum pressure differential that exists between the upstream and downstream volumes they interpose, and then, once opened, , oppose the passage of gas as little as possible.

In addition, when gas enters or exits, the valve must close again as quickly as possible to restrict the flow of gas in the opposite direction, and this undesirable effect is referred to as "reverse flow". known by the Anglo-Saxon term ``.

Passive compressor valves generally include springs that return the valves to their seats.

The above spring results from a compromise.

Ideally, the force exerted by this spring on the valve with which it cooperates is, firstly, such that the gas can open said valve under a low differential pressure; should be low enough so as not to excessively stack the gas passing through, stacking would form an irrecoverable energy loss.

At the same time, the spring is sufficiently stiff to quickly return the valve to its seat when the pressure difference reverses, in order to limit "backflow" and obtain the best possible volumetric efficiency of the compressor. There must be.

In addition to being as energy efficient as possible, passive compressor valves are durable, preferably tight, low maintenance, cheap to manufacture, maintain and repair, and remain as quiet as possible. There must be.

The main causes of wear in valves according to the current state of the art are between the valve and its seat, between the valve and its opening stop, between the return spring and the valve, and between the return spring and its housing. exists at the contact point.

Valve wear is generally more significant when they operate in aggressive chemical and/or particulate conditions. In addition, fouling of the valve can lead to a reduction in its tightness and/or permeability.

Also, valves according to the current state of the art can be damaged by cracking, deformation or even breaking. They generally deteriorate over time due to wear, creep, pitting or surface chipping.

Therefore, a passive compressor valve according to the current state of the art is the subject of French Patent No. 3,061,743, published on August 16, 2019 and belonging to the present applicant, the implementation of a pre-ignition chamber with a valve. It is not very suitable for manufacturing compressors such as those required for.

Indeed, the compressor required by the prechamber for its pilot charge supply must be capable of operating over a wide range of rotational speeds and over a wide range of pressures and temperatures that characterize the operation of reciprocating automotive internal combustion engines. Must be.

In addition, the compressor required to feed the pre-ignition chamber with the valve according to FR 3,061,743 can be operated without repair or maintenance, despite significant variations in the operating conditions to which it is exposed. Must be operable throughout the vehicle's service time.

In this context, passive compressor valves according to the current state of the art make it difficult to achieve a feed compressor suitable for the ignition prechamber with valves.

This is why, especially in the context of the implementation of the prechamber mentioned above, the valve plate with free microballs according to the invention advantageously replaces passive compressor valves according to the current state of the art, and according to a particular embodiment: The valve plate with free microballs according to the invention comprises:
- Particularly permeable so as to offer little resistance to the passage of gas, which is favorable for the energy efficiency of compressors equipped with valves;
is reactive and its switching between open and closed positions takes place under very low differential pressures, which is likewise advantageous for the energy efficiency of compressors equipped with valves;
- Capable of operating over a wide range of frequencies, in particular any compressor equipped with valves operating at variable speeds, for example with valves according to French Patent No. 3,061,743 in automobile combustion engines makes it possible to implement an ignition pre-chamber,
- Durable, allowing thousands of hours of cumulative operation without maintenance, making it suitable for automotive applications and generally reducing maintenance costs for reciprocating compressors;
Robust, self-cleaning and able to cope with aggressive environments or trace amounts of lubricants without affecting its efficiency;
Can operate over a wide temperature range without risk of deformation or loss of performance;
・It is inexpensive to manufacture.

The valve plate with free microballs according to the invention can in fact be applied in a pre-ignition chamber with a valve according to FR 3,061,743. However, the valve plate with free microballs according to the invention requires that, regardless of the nature of the gas, liquid or volume, said gas or liquid passes from the upstream volume to the downstream volume rather than in the opposite direction. It can also be used for any other application of any type or in any field.

A valve plate with free microballs according to the invention separates an upstream volume from a downstream volume and allows fluid to flow from said upstream volume to said downstream volume, but not in the opposite direction. The above valve plate is
- at least one stationary circulation plate hermetically separating the upstream volume from the downstream volume, said plate having at least one circulation orifice straight across its thickness through which fluid can flow; , the end of the orifice appearing in the downstream volume having at least one stationary circulation plate with a microball seat;
- at least one permeable guide plate fixedly housed in the downstream volume parallel to and adjacent to the circulation plate, said plate having at least one guide cylindrical orifice in the direction of its thickness; at least one transparent guide plate, the longitudinal axis of the at least one guide cylindrical orifice being centered on the longitudinal axis of the microball seat;
- at least one microball accommodated with a small play inside the guide cylindrical orifice, said small play causing a flow of fluid through the gap left between said microball and said cylindrical orifice; restricting passage, the microballs rest tightly on a microball seat to close the circulation orifice and prevent fluid flow within the orifice, or the fluid passes through the orifice. at least one microball that is longitudinally translatable within the cylindrical orifice away from the seat to enable flow;
at least one permeable microball stop abutment attached directly or indirectly to the guide cylindrical orifice, the microball and the microball being in contact with each other when said microball is in contact with said abutment; at least one permeable microball stop abutment, which sets a maximum distance between the ball seat and the abutment, the abutment only slightly or not closing the guide cylindrical orifice;
- at least one spacer such that when the microball is in contact with the microball seat, at least a portion of the volume of the microball remains contained within the guide cylindrical orifice; When the microball is in contact with the microball stop abutment, on the one hand, between the microball and the microball seat with which it cooperates, and on the other hand, between the permeable guide plate and the circulation plate. at least one spacer interposed between the permeable guide plate and the circulation plate to maintain said plate at a distance from said plate such that a passage is left for fluid to flow through said plate;
- at least one drainage passageway straight through the permeable guide plate and/or bypassing said plate, said passageway being such that when no microballs are resting on the microball seats, fluid is directed to the upstream volume; at least one exhaust passageway for allowing flow from the downstream volume through the circulation orifice.

A valve plate with free microballs according to the invention is positioned on an extension of the guide cylindrical orifice and is fixedly housed in the downstream volume parallel to and adjacent to the permeable guide plate. a permeable microball stop abutment consisting of a microball bearing area, which is arranged on a stopper plate that is and a discharge passageway that allows fluid to flow from the upstream volume to the downstream volume through the circulation orifice when not resting on the ball seat.

The valve plate with free microballs according to the invention comprises a stopper plate spacer, the stopper plate spacer interposed between the stopper plate and the transparent guide plate to keep the stopper plate at a distance from the plate. , whereby at least a portion of the volume of the microball remains contained within the guide cylindrical orifice when the microball is in contact with the microball bearing area.

The valve plate with free microballs according to the invention comprises a circulation plate, a permeable guide plate, a permeable microball stop abutment, and a spacer, forming a rigid assembly in which the microballs are housed. .

A valve plate with free microballs according to the invention comprises a rigid assembly hermetically housed within an assembly recess separating an upstream volume from a downstream volume.

The valve plate with free microballs according to the invention has an axial stop abutment on the upstream volume, on which the rigid assembly directly rests, and an axial stop abutment on the downstream volume, on which the rigid assembly rests via an assembly retention spring. , an assembly retaining spring bearing on the downstream volume axial stop abutment to urge the assembly recess against the upstream volume axial stop abutment.

The valve plate with free microballs according to the invention comprises a discharge passage formed by at least one axial discharge groove arranged in the inner wall of the guide cylindrical orifice.

The following description of the invention, together with the accompanying drawings, which are provided by way of non-limiting example, provides a better understanding of the invention, its features and the advantages it can offer.

In order to facilitate an understanding of the operation of the valve plate, FIG. The spreading pressure is greater than the spreading pressure within the upstream volume. 2 is a schematic cross-sectional view of a valve plate with free microballs according to the invention and according to the configuration shown in FIG. 1, where the pressure prevailing in the upstream volume is greater than the pressure prevailing in the downstream volume; FIG. 1 is a three-dimensional virtual diagram of a three-stage reciprocating piston compressor with an air-water intercooler, the movable connections of the compressor forming a crank-frame system, and each compression stage of the compressor according to the invention; At least one valve plate with free microballs is received as an inlet valve and at least one valve plate with free microballs according to the invention is received as an outlet valve. 4 is a three-dimensional cross-sectional view of the reciprocating piston compressor shown in FIG. 3, showing in particular the inlet duct and the discharge duct arranged in the compressor head, each of which is free according to the invention; FIG. Opposite the valve plate with microballs. 4 is a three-dimensional exploded view of the reciprocating piston compressor shown in FIG. 3, which clearly shows how the valve plate with free microballs according to the invention is housed within the compressor head; FIG. FIG. 6 is a three-dimensional exploded view of a reciprocating piston compressor similar to that shown in FIG. 5, but from a different angle of view allowing the opposite side of the valve plate with free microballs according to the invention to be observed; It is. 7 is a three-dimensional cross-sectional view of a valve plate with free microballs according to the invention as provided at the inlet of the first compression stage of the reciprocating piston compressor shown in FIGS. 3 to 6; FIG. 7 is a three-dimensional exploded view of a valve plate with free microballs according to the invention as provided at the inlet of the first compression stage of the reciprocating piston compressor shown in FIGS. 3 to 6; FIG. 7 is a three-dimensional view of a valve plate with free microballs according to the invention as provided at the outlet of the first compression stage of the reciprocating piston compressor shown in FIGS. 3 to 6; FIG. Schematic of a valve plate with free microballs according to the invention, with a simple variant containing only a single microball and with the discharge passage formed from three axial discharge grooves arranged in the inner wall of the guide cylindrical orifice FIG. 11 is a schematic cross-sectional view along section line AA of the variant of the valve plate with free microballs according to the invention shown in FIG. 10; FIG.

1 to 11 show various details of the valve plate 1 with free microballs according to the invention, its components, variants and accessories.

As clearly and simply shown in FIGS. 1 and 2, the valve plate 1 with free microballs according to the invention separates an upstream volume 3 from a downstream volume 4, such that the fluid 2 flows from said upstream volume 3. It allows flow into said downstream volume 4, but not in the opposite direction.

1 to 8 and 10 show that the valve plate 1 with free microballs according to the invention comprises at least one fixed circulation plate 5 sealingly separating the upstream volume 3 from the downstream volume 4. The plate 5 has at least one circulation orifice 6 straight across its thickness through which the fluid 2 can flow.

It can also be seen from the above figure that the end of the orifice 6 appearing in the downstream volume 4 has a microball seat 7 and the other end of the orifice 6 is for example It can be seen that it appears in the upstream volume 3 via a convergent inlet orifice 26 which facilitates the inflow and increases the outflow coefficient of the circulation orifice 6.

It is noted that the circulation plate 5 can advantageously be made of hard and mechanically durable steel, or any other material whatever its nature.

The valve plate 1 with free microballs according to the invention also comprises at least one permeable guide plate 9 fixedly housed in the downstream volume 4 parallel to and close to the circulation plate 5. , said plate 9 is traversed straight across its thickness by at least one guide cylindrical orifice 10, the longitudinal axis of which is centered approximately exactly on the axis of the microball seats 7, not necessarily It does not need to be completely parallel to the microball seat 7.

It is noted that the permeable guide plate 9 can be made of plastic material or of any other material, especially sintered steel, due to its considerable light weight and its low manufacturing costs. .

It is also noted that the permeable guide plate 9 can be precisely positioned relative to the circulation plate 5, for example by a centering pin known per se or by any other mechanical centering elements and/or positioning. sea bream.

1, 2, 8, 10 and 11, a valve plate 1 with free microballs according to the invention has at least one microball accommodated with small play inside a guide cylindrical orifice 10. 8, said small play restricts the passage of fluid 2 through the gap left between said microball 8 and said cylindrical orifice 10, and said microball 8 closes the circulation orifice 6. so as to rest hermetically on the microball seat 7 in order to prevent the flow of the fluid 2 in the orifice 6 or to allow the fluid 2 to circulate in the orifice 6. It is noted that it is possible to translate longitudinally within the cylindrical orifice 10 away from the seat 7.

The radial play left between the microball 8 and the guide cylindrical orifice 10 must be small enough for the microball 8 to act as a piston within the guide cylindrical orifice 10, but the Note that 8 must be large enough to be able to move freely within the orifice 10, including under the influence of small pressure differences.

In this respect, the principle of the displacement of the microball 8 within the guide cylindrical orifice 10 may be similar to the principle governing the displacement of a projectile within a blowpipe or the displacement of a bullet within the barrel of a rifle. I understand.

1 to 10, a valve plate 1 with free microballs according to the invention comprises at least one permeable microball stop abutment 11, which is integrated directly or indirectly with a guide cylindrical orifice 10. Note that the maximum distance separating the microball 8 from the microball seat 7 when the microball 8 is in contact with the stop abutment 11 is fixed.

The permeable microball stop abutment 11 blocks the guide cylindrical orifice 10 slightly or not at all, thereby reducing the pressure between the pressure prevailing in the downstream volume 4 and the pressure prevailing in the upstream volume 3. The pressure difference can exert a desired blowpipe effect on the microball 8, keeping it pressed against the microball seat 7 with which it cooperates, or, on the contrary, forcing the fluid 2 Note that the microballs 8 are moved away from the seat 7 to allow the microballs 8 to circulate within the circulation orifice 6.

1, 2, 8 and 10, the valve plate 1 with free microballs according to the invention comprises at least one spacer 12 interposed between the permeable guide plate 9 and the circulation plate 5. I understand.

The spacer 12 comprises at least a portion of the volume of the microball 8 when the microball 8 is in contact with the microball seat 7, regardless of any chamfers or flares that the guide cylindrical orifice 10 may have. The permeable guide plate 9 is kept at a distance from the circulation plate 5 such that the guide plate 9 remains contained within the guide cylindrical orifice 10.

In particular, in FIG. 2, when the microball 8 is in contact with the microball stop abutment 11, a transparent It should be noted that between the guide plate 9 and the circulation plate 5 a passage is left for the fluid 2 to flow.

The spacer 12 may be attached to either the circulation plate 5 or the permeable guide plate 9 as shown in FIG. Note that it can be integrated with both when forming the same part.

The spacer 12 may also be constituted by a separate mechanical part or be part of the environment in which the valve plate 1 with free microballs according to the invention is integrated.

Finally, as shown in FIGS. 1 to 10, the valve plate 1 with free microballs according to the invention has at least one evacuation passage straight through the permeable guide plate 9 and/or bypassing said plate 9. 13, said passageway 13 allows fluid 2 to flow from the upstream volume 3 to the downstream volume 4 via the circulation orifice 6 when the microball 8 is not resting on the microball seat 7. do.

It is noted that the play left between the microball 8 and the guide cylindrical orifice 10 contributes to allowing the fluid 2 to flow from the upstream volume 3 to the downstream volume 4.

1 to 10, the permeable microball stop abutment 11 is positioned on an extension of the guide cylindrical orifice 10, parallel to and adjacent to the permeable guide plate 9. It is noted that it can be constituted by a microball bearing area 16 arranged on a stopper plate 14 fixedly housed in the downstream volume 4 .

In this case, the discharge passage 15 passes straight through the stopper plate 14 in its thickness direction and/or bypasses the stopper plate 14, and when the microball 8 is not resting on the microball seat 7, the fluid 2 Allowing flow from the upstream volume 3 to the downstream volume 4 through a circulation orifice 6 .

If this is the configuration of a valve plate 1 with free microballs according to the invention as shown in FIGS. 1 and 2, a stopper plate spacer 17 is provided between the stopper plate 14 and the permeable guide plate 9. The stopper plate 14 can be interposed to keep it at a distance from the plate 9, so that at least part of the volume of the microball 8 is in contact with the microball bearing area 16. remains contained within the guide cylindrical orifice 10.

The stopper plate spacer 17 can be used with either the stopper plate 14 or the transparent guide plate 9, or if said spacer 17, said stopper plate 14 and said plate 9 form one and the same piece of metal or any other material. Note that it can be integrated with both.

The stopper plate spacer 17 can also be a separate mechanical part, as shown in FIGS. 1 and 2, or can be part of the environment in which the valve plate 1 with free microballs according to the invention is installed.

1 to 7 and 9 show that the circulation plate 5, the permeable guide plate 9, the permeable microball stop spacer 11, and the spacer 12 are assembled by screwing, welding, crimping, or any assembly means known to those skilled in the art. A rigid assembly 19 formed by the microballs 8 is shown housed within said assembly 19.

In this case, as shown in FIGS. 4 to 6, the rigid assembly 19 may be advantageously hermetically housed within an assembly recess 20 separating the upstream volume 3 from the downstream volume 4, and the rigid assembly 19 Alternatively, the assembly recess 20 comprises at least one gasket groove 21 into which a gasket 22 is fitted.

According to this particular configuration of the valve plate 1 with free microballs according to the invention, as shown in FIGS. 1, 2 and 10, the assembly recess 20 has an upstream volume 23 on which the rigid assembly 19 directly rests. The assembly retaining spring 25 may have a lateral axial stop abutment and a downstream volume 24 side axial stop abutment on which the rigid assembly 19 rests by an assembly retention spring 25 , wherein the assembly retention spring 25 It rests on the stop abutment and presses the assembly recess 20 against the axial stop abutment on the upstream volume 23 side.

Advantageously, when the pressure prevailing in the upstream volume 3 is greater than the pressure prevailing in the downstream volume 4, the force exerted on the rigid assembly 19 by the assembly retaining spring 25 is equal to the force exerted on said rigid assembly 19 by the fluid 2. Note that the force exerted by the microballs 8 is greater than the force exerted by the microballs 8, so that the microballs 8 are kept away from the cooperating microball seats 7 and the fluid 2 flows from the upstream volume 3 to the downstream volume 4. I want to be

10 and 11, according to a variant of the valve plate 1 with free microballs according to the invention, the discharge passage 13 is formed from at least one axial discharge groove 27 formed in the inner wall of the guide cylindrical orifice 10. Note that the guide cylindrical orifice 10 retains its ability to guide the microball 8 with small radial play while it moves within the orifice 10.

Operation of the Invention The operation of the valve plate 1 with free microballs according to the invention is easily understood in view of FIGS. 1 to 11.

For ease of understanding, FIGS. 1 and 2 show a valve plate 1 with free microballs according to the invention in which a single microball 8 is provided, but the purpose of the valve plate 1 is includes a large number of microballs 8 as shown in FIGS. 3 to 9.

In Figures 1 and 2, the pressure prevailing in the upstream volume 3 is designated as "P1", while the pressure prevailing in the downstream volume 4 is designated as "P2".

Figure 1 shows what happens when P2 is greater than P1. In this case, the microballs 8 are pressed by P2 onto the microball seats 7 provided at the ends of the circulation orifices 6, which cross the circulation plate 5 straight across the thickness of this plate. ing.

In FIG. 1, the microballs 8, together with the microball seats 7, form a line of tight contact that counteracts the flow of the fluid 2 from the downstream volume 4 to the upstream volume 3.

Figure 2 shows what happens when P1 is greater than P2. As can be seen in the above figure, under a pressure of P1, the microball 8 moves within the guide cylindrical orifice 10 in which it is housed until it comes into contact with the permeable microball stop abutment 11. There is. Note that the guide cylindrical orifice 10 is arranged in the transparent guide plate 9.

As can be seen in FIG. 2, the microball 8 behaves like a bullet in the barrel of a gun, and this function is caused by the guide cylindrical orifice 10 in which the microball 8 is housed with a small play. It is given. As another similarity, the microball 8 also behaves like a projectile propelled by air pressure into the tube of a blowpipe, whose function is also fulfilled by the cylindrical orifice guide 10.

In FIG. 2, P1 is greater than P2, so that the fluid 2 flows from the upstream volume 3 to the downstream volume 4 through the circulation orifice 6 in the passage left between the microball 8 and the microball seat 7. , the space left between the permeable guide plate 9 and the circulation plate 5 by the spacer 12, and the discharge passage 13 passing straight through the permeable guide plate 9 in sequence. Note that the microball 8 is kept away from its microball seat 7 by the flow of fluid 2.

According to the particular configuration of the plate valve 1 with free microballs according to the invention shown in FIGS. 1 and 2, after traversing the discharge passage 13, the fluid 2 presents a permeable microball stop abutment 11. After passing through the space left between the stopper plate 14 and the permeable guide plate 9 and after passing through the discharge passage 15 which cuts straight across the stopper plate 14 in the direction of its thickness, it joins the downstream volume 4. do.

It should be noted in FIGS. 1 and 2 that the space between the stopper plate 14 and the transparent guide plate 9 results from a stopper plate spacer 17 interposed between said stopper plate 14 and said plate 9.

However, the purpose of the valve plate 1 with free microballs according to the present invention is to provide a single microball so that it can meet the needs and expectations of reciprocating piston compressors 52 produced in small, medium and large quantities. Instead of 8, a large number of microballs 8 are provided that operate over short strokes.

The interest in providing the valve plate 1 with free microballs with a large number of microballs 8 is such that the circumference of the ball increases in proportion to its diameter and the projected cross section of said ball increases as a function of the square of its diameter. It is understood that the volume of the ball increases as a function of the cube of its diameter.

Therefore, the smaller the ball, the larger the quotient of its projected cross section divided by its volume.

Consider a solid steel ball. The smaller the ball, the smaller its mass relative to its projected cross section. In other words, the smaller the ball, the lower the mass of steel per unit of projected cross section.

Assume now that the steel ball is housed in a cylinder that can move generally tightly, like a lead bullet in the barrel of a gun.

If the ball is accelerated by a pressure difference extending on each side of a generally tight line of contact that the ball forms with the cylinder, the smaller the ball, the greater the acceleration it will experience for the same pressure difference.

This first observation shows that when a valve plate 1 with free microballs is applied to a reciprocating piston compressor 52 as shown in FIGS. The reason why a large number of microballs 8 are provided inside the orifice 10 will be explained.

The low weight of the microballs 8 brings the microballs 8 back into contact with the microball seat 7 on which they rest and prevents the fluid 2 from flowing from the downstream volume 4 to the upstream volume 3. Avoids the need for springs.

In fact, if the pressure prevailing in the upstream volume 3 is different from the pressure prevailing in the downstream volume 4, the microball 8 is housed in the guide cylindrical orifice 10 with a small play, so that the microball The accelerations experienced by the balls 8 are high due to their low mass relative to their projected cross section.

Said microballs 8 therefore prevent their closure such that "reverse flow" can significantly reduce the overall efficiency of a reciprocating piston compressor 52 equipped with a valve plate 1 with free microballs according to the invention. They can be moved very quickly from their microball seats 7 to their permeable microball stop abutments 11 and vice versa without allowing them to be established at any time.

The movement of the microball 8 translating within its own guiding cylindrical orifice 10, similar to the movement of a projectile in a blowgun, therefore eliminates the return spring as normally included in passive compressor valves according to the state of the art. There is no need to provide

The absence of a return spring allows the free microballs according to the invention to open under very small pressure differences and allow the fluid 2 to pass from the upstream volume 3 to the downstream volume 4. A high degree of reactivity is given to the valve plate 1 having the following characteristics. This feature is favorable for the volumetric and energy efficiency of the reciprocating piston compressor 52 receiving said valve plate 1.

Indeed, unlike passive compressor valves with return springs according to the current state of the art, the valve plate 1 with free microballs according to the invention allows the microballs 8 to lift from their microball seats 7 and the fluid 2 There is no threshold pressure imposed by any return springs to allow flow between upstream volume 3 and downstream volume 4.

In addition, keeping the microballs 8 open in contact with their permeable microball stop abutments 11 does not require overcoming any return spring force and therefore no No load loss occurs.

In fact, when the micro-balls 8 are pressed against the abutment part 11, the circulation of the fluid 2 through the passages left between the micro-balls 8 and their micro-ball seats 7 is controlled by the return spring. There is no need to counter any antagonistic forces that will be exerted on the microball 8.

The wear that normally occurs in the contact area between the return springs and the valves with which they cooperate, on the one hand, and between the return springs and their housing, on the other hand, is also avoided in the context of the valve plate 1 with free microballs according to the invention. In , there is no return spring because the present invention does not provide a return spring.

The reactivity of the opening and closing of the microball 8 is determined by the passage section left for the fluid 2 to bypass the microball 8, i.e. the circulation of the fluid 2 between the microball seat 7 and the downstream volume 4. Note that it can be adjusted by the pressure drop constituted by the passage.

The reactivity can also be adjusted by the pressure drop forming the fluid circulation path 2 connecting the surface of the microball 8 facing the microball seat 7 and the downstream volume 4 .

1 to 11 show, by way of example, a microball 8 resting on a conical microball seat forming an angle of 45 degrees on either side of its axis. According to this non-limiting example, the microballs 8 are made of solid steel and their diameter is 2 millimeters.

The inner diameter of the circulation orifice 6 with which the microballs cooperate is 1.34 mm, and the width of the supporting wall of the microball seat 7 is one-tenth of a millimeter. Contact is established between each microball 8 and their respective microball seat 7 in the center of said support wall, usually at the support wall. A radial play of three-hundredths of a millimeter is left between each microball 8 and the guide cylindrical orifice 10 that houses it.

According to the example shown in FIGS. 1 to 11, each microball 8 was allowed to have a maximum stroke of 4/10 of a millimeter. The stroke must be such that the microball 8 moves from its contact with its microball seat 7 to its contact with its permeable microball stop abutment 11 and vice versa. Corresponds to the distance required.

When the microball 8 is in contact with its permeable microball stop abutment 11, a fluid 2 passes between the microball 8 and the microball seat 7 with which it cooperates, so that approximately A useful area of 1.6 square millimeters remains.

According to the particular configuration of the valve plate 1 with free microballs according to the invention shown in FIGS. 1 to 11, when the microballs 8 are subjected to a pressure difference of 100 mbar between their upper and lower surfaces, the Note that it takes just under 1 millisecond for the microball 8 to move from its contact with the microball seat 7 to its contact with the transparent microball stop abutment 11, or vice versa. I want to be

It is noted that under these conditions, the velocity that the microball 8 obtains when it comes into contact with the microball seat 7 or the permeable microball stop abutment 11 is of the order of 80 cm/s. sea bream.

This speed is lower than the maximum permissible value of the valve in a reciprocating internal combustion engine when the valve is in contact with the seat with which it cooperates. The above-mentioned speed of 80 centimeters per second therefore guarantees the durability of the microball seat 7 on the one hand and the durability of the microball 8 on the other hand.

The friction between the microball 8 and the interior of the guide cylindrical orifice 10 has very low energy due to friction, even when the guide cylindrical orifice 10 is positioned horizontally and thus perpendicular to the direction of gravity. It should also be noted that the dissipation of In fact, the weight of the microballs 8 is only 34 milligrams, according to the non-limiting example shown in FIGS. When doing so, it tends to interfere with the guide cylindrical orifice 10 that houses it.

The low maximum speed obtained by the microballs 8 and the low weight of the microballs 8 result from the low maximum velocity obtained by the microballs 8 and the low weight of the microballs 8 due to the low maximum velocity obtained by the microballs 8 and the low weight of the microballs 8 between each microball 8 and its microball seat 7 or between each microball 8 and its permeable microball stop abutment 11. Note that this gives a low unit kinetic energy of about 34 microjoules that is dissipated at the interface between.

The width of the microball seats 7 and the low kinetic energy dissipated on said seats ensure the durability of the steel microballs 8 and of the microball seats 7, also made of steel, with which they cooperate. do.

It is noted that the microballs 8 may be similar to the balls normally used in ball bearings known per se, ie hardened and optionally coated with hard chrome plating. The very low cost of producing such balls contributes to the low cost of the valve plate 1 with free microballs according to the invention.

It should also be noted that if the microball 8 is not connected to a spring, the microball 8 itself can rotate freely and not expose the exact same surface of the microball seat 7. This allows each microball 8 to permanently clean its entire outer surface, eliminating any impurities or particles that may get between itself and the microball seat 7 with which it cooperates. do.

It should also be noted that the spherical shape of the microballs 8 facilitates the flow of the fluid 2. In fact, before opening into the downstream volume 4 and after passing through the circulation orifice 6, said fluid 2 coming from the upstream volume 3 is left between each microball 8 and its microball seat 7. Must pass through an annular space. Furthermore, when the fluid 2 hits the dome formed by the microballs 8, the fluid 2 is naturally guided by the dome towards the seat 7, thereby making the valve with free microballs according to the invention Plate 1 is given a high runoff coefficient.

It should also be noted that the bearing surface of each microball 8 on its microball seat 7 is large relative to the volume of said microball 8 . As a result, the microballs 8 can be effectively cooled on their microball seats 7 to a temperature close to that of the seats 7.

It should also be noted that since each microball 8 is perfectly spherical and rotates itself during its operation, said microball 8 cannot undergo any temperature-related non-uniform deformation.

As can be easily seen from FIGS. 3 to 6, the valve plate 1 with free microballs according to the present invention has a large surface area relative to the volume of the compression chamber 51 in which the valve plate 1 works when provided with many microballs 8. have

As can be seen from the above, within common sense, the surface should be provided with small and large numbers of microballs 8.

In fact, if the same surface is covered with microballs 8, the sum of the lengths of the contact lines that said microballs 8 form with their seats 7 becomes increasingly larger as the number of microballs 8 increases. . Furthermore, the smaller the microballs 8, the smaller their lift will be in absolute terms, even if the ratio between the lift and the diameter of the circulation orifice 6 is the same.

Let's take a square with sides of 10 mm as an example.

This square can accommodate balls 8 with a diameter of 10 millimeters, or reasonably 16 microballs 8 with a diameter of 2 millimeters. However, the total length of the contact line formed by a microball 8 with a diameter of 2 mm is 3.2 times longer than the length of the contact line formed by a ball with a diameter of 10 mm. Therefore, the stroke of a 2 mm microball 8 is 3.2 times smaller than the stroke of a 10 mm diameter ball, with the same passage cross section remaining for the fluid 2 flowing from the upstream volume 3 to the downstream volume 4. twice as small.

We also consider what happens if we use balls with a diameter of 10 mm instead of 16 microballs 8 with a diameter of 2 mm in order to obtain comparable results with respect to the passage cross-section and the same duration of opening/closing operations. can do.

In order to leave the same passage cross-section for the fluid 2, the lift for a 10 mm diameter ball must be 1.28 mm and not 4/10 mm for a 2 mm diameter microball 8.

Assuming on the one hand the mass of a ball with a diameter of 10 mm and, on the other hand, an unfavorable ratio between the projected cross section and the volume of said ball, when a microball 8 with a diameter of 2 mm moves 4/10 mm, In order to give the ball the acceleration necessary to move a stroke of 1.28 mm in the same time, the ball with a diameter of 10 mm has a pressure difference of 1.7 bar, instead of only 100 mbar for the microball 8. It is necessary to receive That is, 17 times more.

Furthermore, under these conditions, the speed at which a 10 millimeter diameter ball rests on its seat may be 2.9 meters/second. In addition to producing high acoustic emissions, these speeds shorten the life of the ball and seat and are not compatible with the life of most reciprocating piston compressors 52.

When a ball with a diameter of 10 mm contacts its open stop abutment, the ball must also be subjected to a counter pressure difference of 1.7 bar in order to return said ball to its seat within the allotted time. It may also be noted that this negates the volumetric efficiency of the reciprocating piston compressor 52 due to excessive "backflow" resulting from such pressure differences.

Due to the high maximum velocity obtained by a ball with a diameter of 10 mm and the weight of the ball of 4.2 grams, the interface between the ball and its seat or between the ball and its open stop abutment. The kinetic energy dissipated in is 17400 microjoules instead of 34 microjoules dissipated by each microball 8 of 2 millimeters in diameter. On a seat with only 5 times more contact surface, more than 500 times more kinetic energy is dissipated, ie more than 100 times more per unit surface.

For this reason, the valve plate 1 with free microballs according to the invention is designed to work with small microballs 8 distributed in large numbers over the largest possible part of the available surface provided by said valve plate 1. The flow rate of each microball 8 is added to the flow rate of its neighboring ones.

Providing a large number of microballs 8 instead of larger balls also has the advantage that the dead volume in the valve plate 1 with free microballs according to the invention is smaller.

This allows reciprocating piston compressor 52 to be manufactured with a volume ratio high enough to provide acceptable volumetric efficiency.

By being equipped with microballs 8 of small diameter, the valve plate 1 with free microballs according to the invention can be designed to be practically thin and leave almost no dead volume. Therefore, Figures 3 to 9 show a valve plate of only 7 millimeters thick with free microballs, which are housed within a cube of less than 15 centimeters on a side, as shown in Figures 3 to 6. It can be easily integrated into a compact three-stage reciprocating piston compressor 52 that can be housed.

As soon as it includes a valve plate 1 with free microballs according to the invention, such a compressor 52 is disclosed in French Patent No. 3,061,743, published on August 16, 2019 and belonging to the applicant. It is particularly suitable for the implementation of a pre-ignition chamber with a valve according to the following.

In fact, the valve plate 1 with free microballs according to the invention, in addition to its compactness and transparency, can operate at speeds up to 500 revolutions per minute without impairing the performance of the reciprocating piston compressor 52, its acoustic emission or its durability. Compatible with the variable speeds of automobile internal combustion engines, which can vary from 6,500 revolutions per minute to over 6,500 revolutions per minute.

This is due in particular to the fact that the microball 8 does not have a spring and therefore does not have a suitable mode associated with a spring, and said microball 8 has a low inertia.

The compact three-stage reciprocating piston compressor 52 shown in FIGS. It operates at half the speed of the engine, ie at a minimum of 250 revolutions per minute and at a maximum of just over 3000 revolutions per minute.

3 to 6 it can be seen that said compressor 52 comprises an inlet valve 57 and an outlet valve 58, said valves 57, 58 consisting of a valve plate 1 with free microballs according to the invention.

The compressor 52 comprises compressor pistons 60 each movable in translation within a compressor cylinder 56, the pistons 60 together with a crankshaft 61 being better known by the Anglo-Saxon term "Scotch yoke". Note that forming a crank frame system 59 with As a non-limiting example, the stroke of compressor piston 60 is here 17 millimeters.

Configured in this way, the reciprocating piston compressor 52 shown in FIGS. 3-6 is particularly suitable for implementing a pre-ignition chamber with valves, which is the subject of French Patent No. 3,061,743. There is.

Said compressor 52 has a first compression stage consisting of two compressor cylinders 56 of 53 mm bore, which draw air from a common intake duct 53 and deliver said air to a higher pressure in a common delivery duct 54. 62.

The compressor 52 also comprises a second compression stage 63 consisting of a compressor cylinder 56 with a diameter of 40 mm and a third compression stage 64 consisting of a compressor cylinder 56 with a diameter of 22 mm.

Particularly in FIGS. 3 and 5, note the air-water intercooler 65 that cools the air from the first compression stage 62 before it is received by the second compression stage 63.

Particularly in FIGS. 3 and 6, note the air-water intercooler 65 that cools the air from the second compression stage 63 before it is accepted by the third compression stage 64.

Also noted in FIGS. 4-6 is a cooling water chamber 66 that circulates water at a temperature of around 40° C., said water coming from a pump not shown.

The cooling water chamber 66 cools, on the one hand, the air circulating in the air-water intercooler 65 and, on the other hand, the oil accommodated in the compressor casing 67 in which the compressor cylinder 56 is arranged, and The casing 67 in particular houses the crank frame system 59. The function of the oil is to cool and equalize the temperature of the internal moving mechanical components of the reciprocating piston compressor 52, as well as to lubricate them.

Note in FIGS. 3-6 the compressor head 55 closing off the end of the compressor cylinder 56 to form the compression chamber 51. In FIGS.

The compressor head 55 is made of two parts, the first part hermetically housing the valve plate 1 with free microballs according to the invention, and the second part housing the corresponding compression stage 62. , 63, 64, an inlet duct 53 and an outlet duct 54 are formed.

As can be clearly seen in FIG. 4, the valve plate 1 with free microballs is fixed to the second part of the compressor head 55 by plate fixing screws 70 and from said second part by spacing washers 71. The distance is kept at 3mm.

Also, particularly in FIGS. 7 and 8, the circulation plate 5, the permeable guide plate 9, and the stopper plate 14 are arranged with locating pins so as to be integrated into the reciprocating piston compressor 52 shown in FIGS. 3-6. 72, the locating pins 72 cooperate with the assembly screws 68 to position the circulation plate 5, the plate 9 and the stopper plate 14 prior to their assembly within the compressor 52. Clamping together, it can be seen that this is after placing the microballs 8 and the spacer 12, here in the form of a washer inserted between the circulation plate 5 and the permeable guide plate 9.

The valve plate 1 with free microballs, preassembled in this way, forms an assembly ready for assembly, either already provided with a seal 22 or without a seal 22, said assembly being , for example, by an equipment manufacturer to a manufacturer of reciprocating piston compressors 52 as shown in FIGS. 3-6.

Note in FIGS. 4 to 6 the connection socket 69 connecting the intake duct 53 and the exhaust duct 54 formed by the compressor head 55 to the air-water intercooler 65, said socket 69 being provided with a sealing O-ring. , are positioned axially with respect to the compressor casing 67 by an abutment.

The valve plate 1 with free microballs according to the invention therefore makes it possible to produce a reciprocating piston compressor 52 that is efficient, durable and compact and operates over a wide range of speeds and pressures. . In doing so, the valve plate 1 with free microballs according to the invention allows the implementation under optimal conditions of the ignition prechamber with valves that are the subject of French Patent No. 3,061,743.

The valve plate 1 can also be used in applications other than compressors, such as motors, pumps, or for transferring gaseous or liquid fluids from an upstream volume to a downstream volume and vice versa, regardless of the nature of the gas or liquid used. The example and context of the realization of the valve plate 1 with free microballs according to the invention described above is non-limiting, since it can be applied to any machine field of any type where flow is required, but not in the direction. Please note that

The possibilities of the valve plate 1 with free microballs according to the invention are not limited to the above-mentioned applications, the foregoing description being given by way of example only and the details of the implementation described in any other equivalent manner. It is to be understood that the field of the invention is not in any way limited by the substitution of objects.

Claims (7)

A valve plate (1) with free microballs separating an upstream volume (3) from a downstream volume (4), wherein a fluid (2) flows from said upstream volume (3) to said downstream volume (4). ), but not in the opposite direction,
- at least one fixed circulation plate (5) sealingly separating the upstream volume (3) from the downstream volume (4), into which the fluid (2) flows; Straight across its thickness is at least one circulation orifice (6) capable of passing through the microball seat (7), the end of said orifice (6) appearing in said downstream volume (4) at least one fixed circulation plate (5) having;
at least one permeable guide plate (9) fixedly housed in the downstream volume (4) parallel to and in close proximity to the circulation plate (5); Said plate (9) has at least one guide cylindrical orifice (10) straight across its thickness, the longitudinal axis of said at least one guide cylindrical orifice (10) extending from said microball seat. at least one transparent guide plate (9) centered on the longitudinal axis of the section (7);
- at least one microball (8) accommodated with a small play inside said guide cylindrical orifice (10), said small play being such that said microball (8) and said cylindrical orifice (10) ), said micro-balls (8) close said circulation orifice (6) and restrict the passage of said fluid (2) through the gap left between said fluid (2) in said orifice (6). 2) to rest tightly on the microball seat (7) or to allow the fluid (2) to flow through the orifice (6). at least one microball (8) capable of longitudinal translation within said cylindrical orifice (10) away from the seat (7);
- at least one permeable microball stop abutment (11) attached directly or indirectly to said guide cylindrical orifice (10), said microball (8) being attached to said stop (11); The maximum distance between the microball (8) and the microball seat (7) is set when the stop (11) is in contact with the guide cylindrical orifice (10) only slightly. at least one permeable microball stop abutment (11) that is closed or non-closed;
- at least one spacer (12), wherein at least a part of the volume of the microball (8) is in contact with the guide when the microball (8) is in contact with the microball seat (7); The microball (8) remains housed inside the cylindrical orifice (10), while the microball (8) is in contact with the microball stop abutment (11); ) and the microball seat (7) with which it cooperates, on the other hand, the fluid (2) flows between the permeable guide plate (9) and the circulation plate (5). at least one layer interposed between said permeable guide plate (9) and said circulation plate (5) to keep said plate (9) at a distance from said plate (5) so that a passageway is left. one spacer (12),
- at least one evacuation passage (13) straight through the permeable guide plate (9) and/or bypassing the plate (9), the passage (13) being such that the microballs (8) The fluid (2) flows from the upstream volume (3) to the downstream volume (4) via the circulation orifice (6) when not resting on the microball seat (7). Valve plate with free microballs, characterized in that it comprises at least one discharge passage (13), allowing The permeable microball stop abutment (11) is positioned on an extension of the guide cylindrical orifice (10), parallel to and parallel to the permeable guide plate (9). ), the discharge passageway (15) consists of a microball bearing area (16) arranged on a stopper plate (14) fixedly housed in said downstream volume (4) in close proximity to said downstream volume (4); Penetrating straight through the stopper plate (14) in its thickness direction and/or bypassing the stopper plate (14), when the microball (8) is not resting on the microball seat (7), A free micro-organism according to claim 1, characterized in that it allows fluid (2) to flow from the upstream volume (3) to the downstream volume (4) through the circulation orifice (6). Valve plate with balls. a stopper plate spacer (17) is interposed between the stopper plate (14) and the transparent guide plate (9) to keep the stopper plate (14) at a certain distance from the plate (9); Thereby, at least a portion of the volume of the microball (8) is inside the guide cylindrical orifice (10) when the microball (8) is in contact with the microball bearing area (16). Valve plate with free microballs according to claim 2, characterized in that the valve plate remains housed in a . The circulation plate (5), the permeable guide plate (9), the permeable microball stop abutment (11) and the spacer (12) form a rigid assembly in which the microball (8) is housed. The valve plate with free microballs according to claim 1, characterized in that it comprises (19). Claim 4, characterized in that the rigid assembly (19) is hermetically housed in an assembly recess (20) separating the upstream volume (3) from the downstream volume (4). Valve plate with free microballs as described. The assembly recess (20) has an axial stop abutment on the upstream volume (23) on which the rigid assembly (19) directly rests and a downstream axial stop abutment on which the rigid assembly (19) rests via an assembly retention spring (25). a volume (24) side axial stop abutment, and the assembly retaining spring (25) holds the assembly recess (20) against the upstream volume (23) side axial stop abutment. 6. Valve plate with free microballs according to claim 5, characterized in that it bears on an axial stop abutment on the side of the downstream volume (24) for pressing. Freedom according to claim 1, characterized in that the discharge passage (13) is formed by at least one axial discharge groove (27) arranged in the inner wall of the guide cylindrical orifice (10). Valve plate with micro balls.