The present application claims benefit of Brazilian Application no. 10 2013 016280 9, filed Jun. 25, 2013, the contents of which are incorporated herein by reference.
The present invention refers to the improvement in hydraulic coupling for quick coupling, whether it is ISO A or ISO B type or flat face, which makes the system more compact with a better distribution of the coupling forces and with easier machining operation and coupling system between the couplings under a more efficient pressure.
In the hydraulic systems, the power is transmitted and controlled through a liquid under pressure in a closed circuit. The quick couplings are used to switch on and off the fluid conduction line without using special tools or devices.
ISO 7241-1 standard covers the geometry and interface dimensions, and specific requirements of basic performance for the A and B series quick couplings for general purposes.
ISO 16028 standard covers the geometry and interface dimensions, and specific requirements of basic performance for quick hydraulic couplings known as flat face and intended to minimize oil leakage by decoupling, and minimize air insertion by coupling.
Generally, conventional quick socket couplings are intended to couple the plug couplings (pins) that are assembled in the hose ends or the tool disconnection points or implements. Conventional coupling models are presented in the
So, in the
The socket includes a connecting body (1) with a number of conventional balls (9) that follow the height of the ISO 7241-1 standard (
This tightness valve (4) (15) present in those two bodies consists of a sealed pin guided by a guide (3) (17) fixed by an elastic ring (02) (14), being a buffer for the spring (11) (16) that moves the sealed pin (4) (15) from the retaining position to the free fluid flow.
When the parts are connected, the o'ring (10) sealing is responsible for the system tightness. In the plug we can identify, in addition to the ball dimensioned by the height of the ISO 7241-1 standard, the 45° duct exit angle (13).
In the
Therefore, we have from item (18) to (29) components that form the socket coupling that do not have a function to couple under internal pressure. In its turn, from (30) to (45), we have the plug coupling items that, through a series of valves, enables the coupling under pressure. Thus, the socket consists of a vented threaded body (18) that fixes the pin through a thread and sealing (19) that, when uncoupled from the plug coupling, has the function of tightness together with the 2nd valve (28) and the o'ring (25) that also works when the parts are coupled (
The 1st valve (29) has the function of protecting against dirtiness that can go into the socket coupling, and has a final buffer in the connector (20) that shrinks the conventional balls (23) that follow the height of the ISO 16028 standard (
In the plug coupling we have three valves (31) (33) (37) that enable the coupling of the plug part under internal pressure, normal working pressure. The conventional plug capable of coupling under pressure is characterized by a number of valves that separate the pressurized part (44) from the non-pressurized one (41). This model consists of a 1st valve (31) tight by a sealing (30) concerning the non-pressurized environment (41), which has the function of tightness in the plug coupling; the 1st valve positioning is given through the spring (34). The 2nd valve (33) separates the pressurized region (44) from the non-pressurized one (41), and through a relatively small area, this valve (33) can be moved even with the pressurized system. It separates the areas (41) and (44) as an aid for the sealing (42) and (43).
The 3rd valve (37) is responsible for allowing the fluid output from the non-pressurized region (41) because if there was no valve, the non-pressurized area (41) could generate pressure in the fluid at the moment of the coupling, not allowing the coupling movement.
The 3rd valve (37) has a spring (38) and a guide (39) the same way as the other valves.
Next, we will go further by showing the limitations of this current state of the art in the range of quick couplings, which follows the ISO 7241-1 and ISO 16028 standards.
According to the ISO 7241 and ISO 16028 standards, the amount of balls (9) (23) existing in the connector (1) (20) is limited based on the ball diameter (Ø L), the ball collar diameter (Ø A), and the ball spacing (see
The table values below were taken from the Tables 1 and 2 of the ISO 7241-1 standard, which defines the parameters for the coupling projects:
The table values below were taken from the Table 1 of the ISO 16028 standard, which defines the parameters for the face-flat type couplings:
Still according to the ISO standards, the H value, that measures the distance from the beginning of the ball to the plug coupling face, aims to, in conjunction with the specified quota Ø A and Ø L, ensure the distance from the beginning of the groove where the socket coupling connector balls position themselves in relation to the plug coupling face.
A first limitation of the state of the art is that all manufacturers design their socket couplings with a ball diameter according to the Ø L value of the ISO standards, which limits the amount of balls that can be used. This is due to the fact that if the amount of holes (46) (48) is increased dramatically, there is little material left in the connector wall (1) (20) (component that houses the balls), weakening and causing the risk of breaking the connector wall (47) (49), please see
As a direct consequence of such limitation, the socket couplings have an external diameter greater than the necessary to obtain the same internal section of fluid flow, please see
A second limitation refers to the number of contact points of the balls (9) (23) in the plug coupling groove (13) (45), please see
Unfortunately, such limitation reduces the product life cycle because the plug groove (13) (45) is responsible to maintain the plug and socket parts connected, even if the internal fluid is pressurized, that extreme pressure dissipates a considerable power in the plug coupling groove, and the fewer balls (9) (23), the fewer stress relieving points cause premature wearing in the plug coupling groove (13) (45), even in the balls (9) (23), many times about to prevent the operation of the item.
A characteristic of the plug pin that follows the ISO 7241-1 standard is that the plug part groove (13) in the geometry that has no contact with the balls is usually found in two concepts with a 45° exit angle (83) or in radius (100), please see
The conventional geometry of the plug coupling peripheral duct does not allow performance of the machining operation with a usual 93° triangular inserts supported type cutting tool.
In order to occur the coupling under pressure (working pressure) of the plug part of the face-flat couplings, the conventional quick couplings (please see
The conventional face-flat socket couplings do not have the coupling function under working pressure. The only models that allow such an accomplishment have an additional that have the same functional principle as the plug models that couple under pressure (
The first purpose of the present invention is an improvement developed in hydraulic coupling for a greater contact area that employs a smaller diameter in the plug coupling connector balls to the socket coupling, allowing to adopt a greater amount of balls without reducing the material section between the holes that host the balls, giving the same resistance to the connector and a greater support area due to a greater number of balls.
As a result, the coupling of the invention enables a greater mechanical strength dissipation applied in the plug coupling peripheral groove.
Thus, a greater life cycle is obtained for the plug coupling because its peripheral groove relies on a greater number of balls, distributing the axial strength which propagates when the couplings are connected and the system is pressurized. Secondly, it is an improvement of the present invention a hydraulic coupling for a quick coupling, which adopts an asymmetrical geometry of the plug coupling peripheral duct that allows applying a more practical and economic tool.
The innovative geometry of the plug coupling duct enables the machining with a cutting tool with a 93° exit angle support of approximately 27°, which allows using triangular inserts (triangle-shaped tools with three or six cutting edges). The third purpose of the present invention is an improvement in hydraulic coupling for a face-flat type quick coupling, which adopts only one internal in both plug and socket couplings. In the proposed coupling there is no isolated area of the pressurized hydraulic system, however, it is possible to move the because it has an area equalization system, which enables the displacement with a likely strength for a human operation. That called equalizer for the plug coupling, and called equalized for the socket coupling has a similar axial hydraulic strength that propagates in both directions forwards and backwards. Thus, from such compensation, it is possible to move it during the coupling operation in the socket, even if its line is under full working pressure.
The improvement in hydraulic coupling for a quick coupling of the present invention can be better understood through the following detailed description, which is performed based on the following drawings attached listed below:
FIG. 1—axial section from the state of the art of the socket and plug quick couplings, which follow the ISO 7241-1 standard with the uncoupled parts one from another;
FIG. 2—axial section of the socket and plug quick couplings, which follow the ISO 7241-1 standard with the coupled parts one from another;
FIG. 3—axial section from the state of the art of the socket and plug quick couplings, which follow the ISO 16028 standard with the uncoupled parts one from another;
FIG. 4—axial section from the state of the art of the socket and plug quick couplings, which follow the ISO 16028 standard with the coupled parts one from another;
FIG. 5—axial section of the socket and plug quick couplings, which follow the ISO 7241-1 standard with the uncoupled parts one from another, as proposed by the invention;
FIG. 6—axial section of the socket and plug quick couplings, which follow the ISO 7241-1 standard with the coupled parts one from another, as proposed by the invention;
FIG. 7—axial section of the socket and plug quick couplings, which follow the ISO 16028 standard with the uncoupled parts one from another, as proposed by the invention;
FIG. 8—axial section of the socket and plug quick couplings, which follow the ISO 16028 standard with the coupled parts one from another, as proposed by the invention;
FIG. 9—partial side view of the quick plug coupling of the ISO 7241-1 standard;
FIG. 10—partial side view of the quick plug coupling of the ISO 16028 standard;
FIG. 11—isometric view of the connectors, socket coupling connector on the left that follows the ISO 7241-1 standard, and the one that follows ISO 16028 standard on the right;
FIG. 12—side view of the quick plug coupling of the ISO 7241-1 standard, showing two usual manufacture geometries of the plug coupling groove;
FIG. 13—axial section of two plug quick couplings that follow the ISO 16028 standard, and have more than one to perform the coupling under working pressure;
FIG. 14—front view of the socket coupling of the ISO 7241-1 standard, showing the difference between the balls of the conventional model (state of the art) on the left, and the ones of the invention model on the right;
FIG. 15—front view of the socket coupling of the ISO 16028 standard, showing the difference between the balls of the conventional model (state of the art) on the left, and the ones of the invention model on the right;
FIG. 16—partial side view of the quick plug coupling of the ISO 7241-1 standard with the 27° exit groove, as proposed by the invention;
FIG. 17—axial section of the face-flat plug and socket coupling of the ISO 16028, as proposed by the invention;
FIG. 18—axial section of the face-flat plug coupling (ISO 16028) proposed by the invention, showing the equalizer containing the dimensioning model;
FIG. 19—side view of the face-flat coupling proposed by the invention, showing the disassembled components;
FIG. 20—axial section of the face-flat socket coupling of the ISO 16028 standard proposed by the invention with equalized, and its mathematical attribution;
FIG. 21—side view of the equalized;
FIG. 22—axial section of two conventional quick socket couplings, which follow the ISO 16028 standard, and do not have coupling function under working pressure;
FIG. 23—axial section of the face-flat socket coupling of the ISO 16028 standard proposed by the invention, showing in detail the buffer duct for the glove spring;
FIG. 24—schematic views of the “spiralock” thread.
The
The
With a greater number of balls in the connector (49) (65), we reduce stress between the balls (54) (68) in the plug coupling groove (85) because the load is dissipated. In some cases, the plug coupling groove deforms by the stress used, raising the wall at 45° of the plug coupling groove (85). Such deformation is smaller if the number of contact points is greater. Through the balls with a smaller diameter, we enable the coupling to install a greater number of balls, which, consequently, enable a dissipation of the hydraulic form, ensuring a greater life cycle for the plug coupling, and reducing the plug coupling groove deformation, all of this due to the research that gives the coupling a ball different from proposed in order to measure the H dimension of the ISO 7241-1 and ISO 16028 standards.
The
The coupling body (64) has a central pierced wall where the central pin (75) is inserted, fixed by a thread (86), which has a prominent and flat head, hence the name “flat face”.
The equalized (71) slides inside the coupling body (64), being sealed by an o'ring (74). The (71) is kept against the central pin head (75) by a spring (73), which is between the coupling body (64) and an external ring (99). A second spring (72) is assembled around the first spring (73) and is supported on the coupling body (64), and keeps the protection (70) sealed against an existing peripheral internal prominence on the anterior connector face (65) in order to isolate the equalized (71) from the external environment.
Based on the
The table below presents a diameter comparison between the balls mentioned in the ISO 7241-1 standard and the ones used by the invention.
As you can note in the
Please note that the face-flat quick coupling diameter of the invention (Ø 28.57″) also decreases in relation to the ISO 16028 standard, which allows that the coupling is assembled in a more narrow place than its predecessors.
The table below presents a diameter comparison between the balls mentioned in the ISO 16028 standard and the ones used by the invention from the face-flat couplings.
The
Thus, the invention proposes a plug coupling duct geometry (85) that allows machining with a 93° support cutting tool, which supports triangular inserts (triangle-shaped tools with three or six cutting edges), and give the part a geometry in the exit angles of approximately 27° (84).
Through the cutting tool exit angle of approximately 27°, the pin can be manufactured with no application restriction. Hence, the plug couplings can be machined with a tool with a greater amount of cutting edges.
Please note that it is not only the duct exit (85) to have an angle less than 27°, but there are two more areas that need to follow the same limit. However, such geometry does not impair the plug coupling functioning. Thus, such geometry allows using the 93° supporting tool where once it did not allow manufacturing them. This allows a higher lifetime of the cutting tool that in addition to having a larger number of sharp edges also ensures the tool a geometry more resilient to the depth of the cut in relation to the ones normally used in the manufacturing process. In addition, there is the possibility of eliminating the use of a finishing tool because the triangular geometry tool is generally used in a buffing material, followed by a finishing geometry. With the new procedure, the buffing tool is also responsible for the finishing because the plug coupling geometry is no more a limit.
The
The
This equalizer can be dimensioned following the principle of equality of areas where the respective area of the ØU must be similar to the ØW area less the ØK area. Such condition allows developing the couplings of the ISO 16028 with different sizes. As the ØK is defined by the standard through ISO, we can use the other two variables (ØU and ØW) to develop the plug couplings of the invention. Although the equalized is the secret of coupling functioning, two foundations are necessary for the proper system functioning.
The buffer (92) serves to give a stopping place to the at the moment of the coupling under pressure. This is due to fact that, by the time of the coupling, the equalization gets lost because in the ØK region, there is no more than one sealing point (77) with the standard plug pin (79). Hence, the strength goes from equalized to axial in the opposite direction of the coupling, which takes the (76) into the coupling with a significative strength. That movement is interrupted by the buffer (92), and if there was no buffer, the movement strength would be propagated in the spring (80), and could damage it.
The breather (90) is also needed for the system because in the spring chamber (80), when the plug coupling is coupled into the socket coupling, the chamber volume (91) decreases, and the air in the spring chamber can get compact and prevent the coupling to occur because the equalizer (76) does not move due to the air pressure. The problem is solved with a system where the air can freely enter and exit from that chamber (91). The breather (90) is exactly this, an environment, generally a hole, which helps the air input and output from the spring chamber; an o'ring (89) sealing can be applied to avoid dirtiness, and works as a filter.
The plug coupling comprehends an anterior cylindrical part (79), also called coupling pin, which is threaded in a posterior cylindrical part (82), also called coupling body. The equalizer (76) comprehends a ØU cylindrical body, a closed head (95) where a sealing (78) is hosted, before the ØK head. The flap has holes (96) for external oil throughput into the interior (76) or vice versa. The coupling pin (79) has an peripheral internal groove (98) to position a sealing O-ring against the ØK head followed by a second peripheral internal groove (97) for a special sealing that also seals against the ØK head
The coupling body (82) has a peripheral groove (93) for a ØU sealing O-ring mounting. In one chamber (91) located between the equalizer body (76) and the coupling body (82) is placed a spring (80). The coupling body (82) has an internal buffer (92), so there is a stopping place at the moment the coupling under pressure occurs. This is necessary to couple the couplings.
The standard coupling pin (79) has a peripheral external groove (89) with a breather hole (90) for the air outlet when the coupling is being coupled. This is needed because in the spring chamber (91), when it couples the couplings, the area volume decreases, and the air inside the spring chamber (91) can pressurize itself and disrupt the coupling, because the equalizer (76) does not move due to a counter-pressure.
The
The invention lays down the socket coupling, where ØQ is less than ØK within a certain range of difference between both dimensions. The equalized (71) presents two peculiar characteristics, that is, there is a specific point where ØQ enables the part coupling under pressure, and does not enable that the opens, leaking oil in the environment. Thus, if we decrease the ØQ, the is becoming less sealed, however it couples with increasingly residual pressure. The invention is different due to the fact that the equalizer (71) has ØQ<ØK.
The springs (72) (73) are concentric and press the equalizer s (71) and the protection s (70), acting independently. So, there is no force opposite to the spring (73) of the equalization (71), which allows the coupling to be smoother. The spring (73) of the equalized (71) is placed inside the spring (72) of the protection (70), allowing an intelligent arrangement, and that uses an inefficient space, reducing the coupling length and making the distance traveled by the oil inside the coupling to be smaller. This helps to reduce load loss inside the. Such spring arrangement one inside the other (87), both inside the protection (70) is thanks to the equalized (71), which has the ØQ less than ØK that creates space for the concentric assembly of the two springs (72) (73).
In the
In the
The
Number | Date | Country | Kind |
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102013016280.9 | Jun 2013 | BR | national |