Shock excitation rotary valve for stabilizing pressure of throttling opening and shoulder and shaft sleeve of shock excitation rotary valve

Abstract

The invention discloses a vibration excitation rotary valve for stabilizing the pressure of a throttling opening and a circular bead and a shaft sleeve of the vibration excitation rotary valve, and belongs to the field of electro-hydraulic vibration excitation. The vibration excitation rotary valve comprises a valve body, a valve sleeve and a valve element. The valve element is driven by an external motor to continuously rotate, a plurality of circular beads are arranged on the valve element in the axial direction, a plurality of throttling grooves are evenly formed in each circular bead in the circumferential direction, and the key improvement is that pre-openings are formed in the two sides of each throttling groove in the circumferential direction. And a plurality of T-shaped windows are correspondingly formed in the valve sleeve. When the valve element rotates, the throttling groove and the T-shaped window are overlapped in the radial direction to form a variable throttling opening which is opened and closed periodically. Before the main throttling area is completely opened, the pre-opening and the edge of the window can form a tiny pilot overflowing area in advance, so that the through-flow area of the throttling opening is smoother along with the change of the rotating angle, and active control over the pressure acceleration of the throttling opening is achieved. Through collaborative design of the pre-opening and the T-shaped window, hydraulic impact and pressure sudden change caused by instantaneous opening and closing of a valve port of a traditional rotary valve are effectively relieved, the working stability and reliability of the excitation rotary valve under the high-frequency working condition are remarkably improved, and vibration noise is reduced.

Description

Technical Field

[0001] This invention belongs to the field of electro-hydraulic excitation, and specifically relates to an excitation rotary valve for stabilizing throttling pressure, as well as its shoulder and bushing. Background Technology

[0002] Vibration has a dual nature in the industrial field: on the one hand, uncontrolled vibration can cause equipment wear, decreased precision, structural fatigue, and even safety accidents; on the other hand, controlled vibration is widely used in vibration testing, screening, processing, and energy recovery, becoming a key technology for improving production efficiency and process levels. Electro-hydraulic vibration systems, due to their advantages of high excitation force, high power density, and ease of control, play an irreplaceable role in these high-power, heavy-load applications.

[0003] The core of an electro-hydraulic excitation system lies in its control valve. Traditional servo valves or directional valves based on the spool principle are constrained by inertial forces, resulting in a bottleneck in dynamic response frequency and making it difficult to meet the high-frequency excitation requirements at the kilohertz (kHz) level. To address this, rotary excitation valves have emerged. These valves periodically modulate the oil circuit through continuous rotation of the valve spool, theoretically overcoming the inertial limitation and achieving a higher response frequency.

[0004] In the prior art, Chinese patent document CN101718291A discloses a "high-flow-rate high-frequency electro-hydraulic excitation control valve drive system," representing a significant advancement in this field. This technology employs a dual-degree-of-freedom valve core design, meaning the valve core, while continuously rotating driven by a hydraulic motor, can also slide axially via an end hydraulic cylinder. The valve core has multiple shoulders, each with circumferentially grooved grooves (throttling grooves), and adjacent shoulder grooves are staggered. Correspondingly, the valve sleeve has multiple rings of windows. The rotation of the valve core causes a periodic change in the overlap area between the shoulder grooves and the valve sleeve windows, thereby outputting a high-frequency pulsating flow rate. The axial sliding of the valve core continuously adjusts the amplitude of this overlap area change, thus controlling the amplitude of the output vibration. This system replaces direct motor drive with hydraulic drive, aiming to solve the problems of insufficient driving torque and system overload under high-flow, high-frequency conditions, and raising the excitation frequency to the 2000Hz level.

[0005] However, while pursuing high frequency and large flow rate, existing technologies and similar rotary valves have introduced a new and prominent problem: hydraulic shock and pressure surges. Due to the high-speed rotation of the valve core, the switching between on and off states of the oil circuit is extremely rapid. At the moment when the throttle orifice is about to fully open or close, the flow rate of the oil flowing through the throttle orifice changes drastically, causing severe pulsations or even shocks in the oil pressure. This periodic pressure surge (or pressure spike) can cause multiple hazards: first, it generates strong vibrations and noise, affecting the system's working environment and stability; second, it forms harmful hydraulic hammering, accelerating the fatigue wear of key friction pairs such as the valve core and valve sleeve, reducing the valve's service life and reliability; third, pressure fluctuations may be transmitted in reverse to the hydraulic pump source and other components, affecting the smooth operation of the entire hydraulic system. Therefore, how to effectively suppress the inherent pressure shock and improve the operational stability and durability of rotary electro-hydraulic vibration valves while ensuring their high-frequency and high-flow-rate working capabilities has become a key technical challenge that urgently needs to be solved for the development of rotary electro-hydraulic vibration valves towards higher performance. Summary of the Invention

[0006] To address the aforementioned problems, this invention proposes a vibratory rotary valve with a stable throttling orifice pressure, along with its shoulder and bushing. The concept lies in setting a pre-opening on the variable throttling orifice formed by the valve sleeve and valve core to control the pressure increase experienced by the rotary valve during valve opening and closing, thereby maintaining the dynamic stability of the rotary valve.

[0007] In a first aspect, the present invention proposes an excitation rotary valve for stabilizing throttling pressure, comprising a valve sleeve 2, an axially extending valve core 3 disposed in the inner cavity of the valve sleeve 2, and a valve body 1 connected to the outside of the valve sleeve 2. The power end of the valve core 3 is connected to an external motor through a power ring 7, and a support ring 16 is connected to the end of the valve core. The support ring 16 contacts the valve sleeve 2. The valve core 3 is provided with several shoulders in sequence from the power end to the end. The rotation direction of the valve core 3 is defined as circumferential. Several throttling grooves 15 are evenly arranged on the shoulders along the circumferential direction. Pre-openings 14 are provided on both sides of the circumferential direction of the throttling grooves 15. The side of the pre-openings 14 closest to the valve core is sealed with a groove bottom 141. The valve sleeve 2 has several flush windows and an oblong hole 22 from the power end to the end. The windows can be radially overlapped with the throttling groove 15 by the rotation of the valve core 3 relative to the valve sleeve 2 to form a variable throttling orifice. The oblong hole 22 connects to the inner cavity of the valve sleeve 2 to form a return oil channel. The valve body 1 has an annular cavity with several connecting windows or waist-shaped holes 22; the valve body 1 has several oil ports, which are respectively connected to the annular cavity to form several oil chambers.

[0008] More specifically, the shoulders fitted on the valve core 3 from the beginning to the end are, in sequence, the first shoulder 10, the second shoulder 11, the third shoulder 12 and the fourth shoulder 13; The contact surfaces of the first shoulder 10, the second shoulder 11, the third shoulder 12 and the fourth shoulder 13 with the bushing 2 are provided with pressure equalization grooves 9 along the circumferential direction; the throttling grooves 15 on the first shoulder 10 and the third shoulder 12 have the same phase distribution, and the throttling grooves 15 on the second shoulder 11 and the fourth shoulder 13 have the same phase distribution.

[0009] More specifically, the phase of the throttling groove 15 on the second shoulder 11 and the fourth shoulder 13 differs from the central angle of the valve core by 90°.

[0010] More specifically, the windows on the valve sleeve 2 from the power end to the end include a first window 17, a second window 19, a third window 20 and a fourth window 23, which can be radially aligned with the first shoulder 10, the second shoulder 11, the third shoulder 12 and the fourth shoulder 13 by rotating the valve sleeve 2 relative to the valve core 3.

[0011] More specifically, the oil ports provided on the valve body 1 include a first oil drain port 23, a first working port 24, an oil inlet port 25, a second working port 26, and a second oil drain port 27; the first oil drain port 23 connects to the first window 17 to form valve cavity P, the first working port 24 connects to the second window 19 to form valve cavity T1, the oil inlet port 25 connects to the third window 20 to form valve cavity T2, the second working port 26 connects to the fourth window 21 to form valve cavity A, and the second oil drain port 27 connects to the oblong hole 22 to form valve cavity B.

[0012] More specifically, the power ring 7 is provided with a pin hole 8, which is connected to the output end of an external motor through a connector.

[0013] More specifically, the window is T-shaped, consisting of an axial arm and a circumferential arm; the circumferential arm is connected to the power end of the axial arm and is evenly divided by the central axis of the axial arm; the two circumferential sides of the axial arm are arc-shaped or wedge-shaped, each composed of sides of equal length; the shape of the pre-opening 14 is any one of arc, triangle, U-shape, or trapezoid.

[0014] More specifically, a groove 18 is provided between adjacent windows on the outer side of the valve sleeve 2, and a sealing ring is provided in the groove 18.

[0015] More specifically, the end of the support ring 16 is connected to a plug 4, the end of the valve sleeve 2 is connected to an end cap, and the plug is rotatably connected to the end cap 6 via a bearing 5.

[0016] Secondly, the present invention proposes a shoulder for the above-mentioned oscillating rotary valve for stabilizing the throttling pressure. The shoulder is uniformly provided with a plurality of throttling grooves 15 along the circumference. Pre-openings 14 are respectively provided on both sides of the circumference of the throttling grooves 15. The bottom of the groove is sealed on the side of the pre-opening 14 closest to the valve core. The shape of the pre-opening 14 is any one of arc, triangle, U-shape, and trapezoid.

[0017] Thirdly, the present invention proposes a bushing for the above-mentioned oscillating rotary valve for stabilizing throttling pressure. The bushing 2 has several flush windows and an oblong hole 22 from the power end to the end. The windows can be radially overlapped with the throttling groove 15 of the valve core 3 by the rotation of the external valve core 3 relative to the valve sleeve 2 to form a variable throttling orifice. The oblong hole 22 connects to the inner cavity of the valve sleeve 2 to form a return oil channel. The window is T-shaped and consists of an axial arm and a circumferential arm. The circumferential arm is connected to the power end of the axial arm and is evenly divided by the central axis of the axial arm. The two circumferential sides of the axial arm are arc-shaped or wedge-shaped, each composed of equal-length sides.

[0018] During operation, the external motor drives the valve core 3 to rotate continuously at high speed through the power ring 7, and the pressurized oil is continuously supplied to the valve chamber T2 from the oil inlet 25; each throttling groove 15 on the valve core rotates with the valve core and periodically overlaps radially with the axial arm area of ​​the corresponding window on the valve sleeve.

[0019] When the rotary valve is in the first working position, the throttling grooves on the second shoulder 11 and the fourth shoulder 13 overlap with the second window 19 and the fourth window 21 on the valve sleeve 2, respectively. High-pressure oil enters from the inlet 25 of the valve body 1, flows through the axial arm of the third window 20, then through the cavity formed between the valve sleeve 2 and the valve core 3, and flows out from the variable throttling orifice formed by the overlap of the throttling groove 15 on the second shoulder 11 and the second window 19, and finally flows out from the first working port 24 on the valve body 1. Low-pressure oil flows in from the second working port 26 of the valve body 1, passes through the variable throttling orifice formed by the throttling groove on the fourth shoulder 13 and the fourth window 21, then through the cavity formed between the valve sleeve 2 and the valve core 3, flows out from the waist-shaped hole, and finally flows out from the second drain port 27 on the valve body 1.

[0020] When the rotary valve is in the second working position, the throttling grooves on the first shoulder 10 and the third shoulder 12 overlap with the first window 17 and the third window 20 on the valve sleeve 2, respectively. High-pressure oil enters from the oil inlet 25 of the valve body 1, flows through the variable throttling orifice formed by the overlap of the throttling groove 15 on the third shoulder 12 and the axial arm of the third window 20, then flows through the cavity formed between the valve sleeve 2 and the valve core 3, and flows out from the axial arm of the fourth window 21, and finally flows out from the second working port 26 on the valve body 1. Low-pressure oil flows in from the first working port 24 of the valve body 1, passes through the circumferential arm of the second window 19, then passes through the cavity formed between the valve sleeve 2 and the valve core 3, and flows out from the variable throttling orifice formed by the overlap of the groove on the second shoulder 10 and the axial arm of the first window 17, and finally flows out from the first drain port 23 on the valve body 1.

[0021] Before the main flow area of ​​the throttling groove is fully aligned with the window, the pre-openings on both sides first contact the edge of the window and form a very small initial flow area. Establishing a pilot, controllable small flow before the main flow passes helps stabilize the system pressure and may reduce cavitation, avoiding a sharp spike in hydraulic pressure when the main throttling orifice suddenly opens, thus making the pressure rise more gradual.

[0022] The flow area of ​​a variable throttling orifice is determined by the overlap area of ​​the window and the throttling groove. Because the axial arm edge of the window is arc-shaped or wedge-shaped, the overlap area changes continuously and smoothly with the valve core rotation angle, rather than abruptly opening / closing. This helps reduce pressure shock.

[0023] The beneficial effects of this invention include: 1. The pre-opening structural design reduces pressure fluctuations during valve switching, making switching more stable, reducing vibration noise, and improving the overall dynamic stability of the rotary valve.

[0024] 2. The pre-opening structure has a flow gradient that gradually increases from small to large, which can gradually adjust the flow rate during the valve opening and closing stage, effectively mitigating the water hammer effect caused by instantaneous pressure impact, and enhancing the structural reliability and operational safety of the excitation system under long-term high-frequency conditions.

[0025] 3. The measures of setting a pre-opening on the valve core throttling groove and changing the shape of the axial arm part of the valve sleeve window work together to control the gradient change law of the flow area of ​​the throttling orifice. The two measures can be used alone or in parallel, and can be applied to other types of vibrating rotary valves, thus increasing the application range.

[0026] 4. The present invention has a simple structural design and stable working performance. It can improve the stability of the excitation rotary valve without the need for additional parts and has good engineering promotion value. Attached Figure Description

[0027] Figure 1 This is a structural diagram of the vibration-excited rotary valve for stabilizing the throttling orifice pressure of the present invention.

[0028] Figure 2 This is an axial cross-sectional view of the vibration-excited rotary valve for stabilizing the throttling orifice pressure of the present invention.

[0029] Figure 3 This is a structural diagram of the valve core of the present invention.

[0030] Figure 4 This is a detailed view of the pre-opening of the present invention.

[0031] Figure 5 This is a structural diagram of the valve sleeve of the present invention.

[0032] Figure 6 This is a structural diagram of the valve body of the present invention.

[0033] Figure 7a This is a schematic diagram of the valve core of the present invention when it is about to open and operate at the first working port.

[0034] Figure 7b This is a schematic diagram of the valve core of the present invention when the first working port is fully operational.

[0035] Figure 7c This is a schematic diagram of the valve core of the present invention when it is about to open and operate at the second working port.

[0036] Figure 7d This is a schematic diagram of the valve core of the present invention when the second working port is fully operational.

[0037] Figure 8 This is a schematic diagram illustrating the change in the throttling orifice area of ​​the present invention.

[0038] Figure 9a This is a comparison chart of the excitation pressure curves with and without pre-opening in the embodiments of the present invention.

[0039] Figure 9b This is a comparison diagram of oil port pressure with and without pre-opening in an embodiment of the present invention.

[0040] Figure 10a This is the first style diagram of the pre-opening of the present invention.

[0041] Figure 10b This is a second style diagram of the pre-opening of the present invention.

[0042] Figure 10c This is the third style diagram of the pre-opening of the present invention.

[0043] Figure 10d This is the fourth style diagram of the pre-opening of the present invention.

[0044] Figure 11a This is the first style diagram of the window of the present invention.

[0045] Figure 11b This is the second bottom view of the window of the present invention.

[0046] Figure 12 This is a perspective view of the oil chamber of the vibrating rotary valve for stabilizing the throttling orifice pressure according to the present invention.

[0047] Figure 13 This is a diagram showing the pre-opening dimensions of the experimental group in this embodiment of the invention. Detailed Implementation

[0048] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0049] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0051] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0052] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0054] The present invention will now be described in detail with reference to the accompanying drawings and exemplary embodiments.

[0055] according to Figure 1 and Figure 2 The present invention proposes a vibratory rotary valve for stabilizing throttling pressure, comprising a valve sleeve 2, an axially extending valve core 3 disposed in the inner cavity of the valve sleeve 2, and a valve body 1 connected to the outside of the valve sleeve 2. according to Figure 3 The power end of the valve core 3 is connected to an external motor via a power ring 7, and a support ring 16 is connected to the end of the valve core, which contacts the valve sleeve 2; the valve core 3 is provided with several shoulders sequentially from the power end to the end; the rotation direction of the valve core 3 is defined as circumferential; several throttling grooves 15 are evenly arranged along the circumferential direction on the shoulders; according to Figure 4 The throttling groove 15 has pre-openings 14 on both sides of its circumference, and the side of the pre-opening 14 closest to the valve core is sealed with a groove bottom 141. according to Figure 5 The valve sleeve 2 has several flush windows and an oblong hole 22 from the power end to the end. The windows can be radially overlapped with the throttling groove 15 by the rotation of the valve core 3 relative to the valve sleeve 2 to form a variable throttling orifice. The oblong hole 22 connects to the inner cavity of the valve sleeve 2 to form a return oil channel. The valve body 1 has an annular cavity with several connecting windows or waist-shaped holes 22; the valve body 1 has several oil ports, which are respectively connected to the annular cavity to form several oil chambers.

[0056] More specifically, the shoulders fitted on the valve core 3 from the beginning to the end are, in sequence, the first shoulder 10, the second shoulder 11, the third shoulder 12 and the fourth shoulder 13; The contact surfaces of the first shoulder 10, the second shoulder 11, the third shoulder 12 and the fourth shoulder 13 with the bushing 2 are provided with pressure equalization grooves 9 along the circumferential direction; the throttling grooves 15 on the first shoulder 10 and the third shoulder 12 have the same phase distribution, and the throttling grooves 15 on the second shoulder 11 and the fourth shoulder 13 have the same phase distribution.

[0057] In some embodiments, the phase of the throttling grooves 15 on the second shoulder 11 and the fourth shoulder 13 differs from the central angle of the valve core by 90°.

[0058] In some embodiments, according to Figure 6 The windows on the valve sleeve 2, from the power end to the end, include a first window 17, a second window 19, a third window 20, and a fourth window 23, which can be radially aligned with the first shoulder 10, the second shoulder 11, the third shoulder 12, and the fourth shoulder 13 by rotating the valve sleeve 2 relative to the valve core 3.

[0059] In some embodiments, according to Figure 12 The oil ports provided on the valve body 1 include a first oil drain port 23, a first working port 24, an oil inlet port 25, a second working port 26, and a second oil drain port 27. The first oil drain port 23 connects to the first window 17 to form valve cavity P, the first working port 24 connects to the second window 19 to form valve cavity T1, the oil inlet port 25 connects to the third window 20 to form valve cavity T2, the second working port 26 connects to the fourth window 21 to form valve cavity A, and the second oil drain port 27 connects to the oblong hole 22 to form valve cavity B.

[0060] In some embodiments, the power ring 7 is provided with a pin hole 8, which is connected to the output end of an external motor through a connector.

[0061] In some embodiments, the window is T-shaped, consisting of an axial arm and a circumferential arm; the circumferential arm is connected to the power end of the axial arm and is evenly divided by the central axis of the axial arm; according to Figures 11a-11b The two circumferential sides of the axial arm are either arc-shaped or wedge-shaped, each composed of sides of equal length. Figures 10a-10d It showcases the available styles for the pre-opening, namely any one of the following: arc, triangle, U-shape, and trapezoid.

[0062] In some embodiments, a groove 18 is provided between adjacent windows on the outer side of the valve sleeve 2, and a sealing ring is provided in the groove 18.

[0063] In some embodiments, a plug 4 is connected to the end of the support ring 16, and an end cap is connected to the end of the valve sleeve 2. The plug is rotatably connected to the end cap 6 via a bearing 5.

[0064] according to Figure 8 During operation, the external motor drives the valve core 3 to rotate continuously at high speed through the power ring 7, and the pressurized oil is continuously supplied to the valve chamber T2 from the oil inlet 25; each throttling groove 15 on the valve core rotates with the valve core and periodically overlaps radially with the axial arm area of ​​the corresponding window on the valve sleeve.

[0065] according to Figures 7a-7bWhen the rotary valve is in the first working position, the throttling grooves on the second shoulder 11 and the fourth shoulder 13 overlap with the second window 19 and the fourth window 21 on the valve sleeve 2, respectively. High-pressure oil enters from the oil inlet 25 of the valve body 1, flows through the axial arm of the third window 20, then through the cavity formed between the valve sleeve 2 and the valve core 3, and flows out from the variable throttling orifice formed by the overlap of the throttling groove 15 on the second shoulder 11 and the second window 19, and finally flows out from the first working port 24 on the valve body 1. Low-pressure oil flows in from the second working port 26 of the valve body 1, passes through the variable throttling orifice formed by the throttling groove on the fourth shoulder 13 and the fourth window 21, then through the cavity formed between the valve sleeve 2 and the valve core 3, flows out from the waist-shaped hole, and finally flows out from the second drain port 27 on the valve body 1.

[0066] according to Figures 7c-7d When the rotary valve is in the second working position, the throttling grooves on the first shoulder 10 and the third shoulder 12 overlap with the first window 17 and the third window 20 on the valve sleeve 2, respectively. High-pressure oil enters from the oil inlet 25 of the valve body 1, flows through the variable throttling orifice formed by the overlap of the throttling groove 15 on the third shoulder 12 and the axial arm of the third window 20, then flows through the cavity formed between the valve sleeve 2 and the valve core 3, and flows out from the axial arm of the fourth window 21, and finally flows out from the second working port 26 on the valve body 1. Low-pressure oil flows in from the first working port 24 of the valve body 1, passes through the circumferential arm of the second window 19, then passes through the cavity formed between the valve sleeve 2 and the valve core 3, and flows out from the variable throttling orifice formed by the overlap of the groove on the second shoulder 10 and the axial arm of the first window 17, and finally flows out from the first drain port 23 on the valve body 1.

[0067] Before the main flow area of ​​the throttling groove is fully aligned with the window, the pre-openings on both sides first contact the edge of the window and form a very small initial flow area. Establishing a pilot, controllable small flow before the main flow passes helps stabilize the system pressure and may reduce cavitation, avoiding a sharp spike in hydraulic pressure when the main throttling orifice suddenly opens, thus making the pressure rise more gradual.

[0068] The flow area of ​​a variable throttling orifice is determined by the overlap area of ​​the window and the throttling groove. Because the axial arm edge of the window is arc-shaped or wedge-shaped, the overlap area changes continuously and smoothly with the valve core rotation angle, rather than abruptly opening / closing. This helps reduce pressure shock.

[0069] A comparative experiment was conducted to assess the pre-opening effect of the aforementioned excitation rotary valve. The experiment involved installing two valve cores into two excitation rotary valves. The shoulder diameter of both sets of valve cores was 16 mm, and each shoulder had two evenly distributed throttling grooves. The circumferential length of the throttling grooves was 6.12 mm, and the axial width was 4 mm. The throttling groove 15 of the control group did not have a pre-opening, while the throttling groove 15 of the experimental group had a U-shaped pre-opening 14. Each U-shaped pre-opening 14 was formed by splicing a rectangle close to the window and a semicircle away from the window. The rectangle was 1.2 mm long and 1 mm wide, and the radius of the semicircle was 0.6 mm. The long side of the rectangle coincided with the straight side of the semicircle.

[0070] The system pressure was set to 47.5 MPa under no-load conditions. The controller of the vibratory rotary valve sent a control signal to the hydraulic power component—the servo motor. The motor drove the valve core to rotate. The valve core speed was set to the same value in both experiments. A pressure sensor was installed at the output section of the first working port of the rotary valve to detect the corresponding pressure change at the first working port. The experimental results are as follows: Figure 9a As shown, it can be clearly seen that the pressure change rate of the first working port of the control group is larger when the valve enters the corresponding working position, while the pressure change of the first working port of the experimental group is more gradual and the pressure change rate is smaller during the same period.

[0071] The results indicate that the pre-opening setting reduces the pressure change rate of the vibratory rotary valve during operation, thereby reducing the pressure impact during the switching phase and improving its stability.

[0072] Similarly, control and experimental groups were set up to conduct water hammer effect experiments. The pressure sensor was set at the oil inlet of the excitation rotary valve. The initial system pressure was set to 1.5 MPa. The overlap area between the throttling groove 15 and the window on the valve core was maximized, that is, the valve port was at its maximum opening. At an instant, the controller of the excitation rotary valve was instructed to output a step signal to control the valve port from its maximum opening to complete closure. The pressure change at the oil inlet was observed and recorded.

[0073] Figure 9b The experimental results show that, at the moment the valve closes, the peak pressure at the inlet of the control group reaches 4.72 MPa, exceeding the set system pressure by 213%, while the peak pressure of the experimental group is only 2.98 MPa, exceeding the set system pressure by only 99%. The peak pressure of the experimental group is 36% lower than that of the control group, and the water hammer effect is significantly reduced, which is sufficient to verify the role of pre-opening in reducing hydraulic shock and mitigating the water hammer effect.

Claims

1. A vibration-induced rotary valve for stabilizing throttling pressure, characterized in that: It includes a valve sleeve (2), and an axially extending valve core (3) is provided in the inner cavity of the valve sleeve (2). A valve body (1) is connected to the outside of the valve sleeve (2). The power end of the valve core (3) is connected to an external motor through a power ring (7), and the end of the valve core is connected to a support ring (16), which contacts the valve sleeve (2). The valve core (3) is provided with several shoulders from the power end to the end. The rotation direction of the valve core (3) is defined as circumferential. Several throttling grooves (15) are uniformly arranged along the circumferential direction on the shoulders. Pre-openings (14) are provided on both sides of the circumferential direction of the throttling grooves (15), and the bottom of the groove (141) is sealed on the side of the pre-opening (14) close to the valve core. The valve sleeve (2) is provided with several flush windows and an oblong hole (22) from the power end to the end. The windows can be radially superimposed with the throttling groove (15) by the rotation of the valve core (3) relative to the valve sleeve (2) to form a variable throttling orifice; the oblong hole (22) connects to the inner cavity of the valve sleeve (2) to form a return oil channel. The valve body (1) is provided with an annular cavity containing several connecting windows or waist-shaped holes (22); the valve body (1) is provided with several oil ports, which are respectively connected to the annular cavity to form several oil chambers.

2. The oscillating rotary valve for stabilizing throttling pressure according to claim 1, characterized in that: The shoulders fitted on the valve core (3) from the beginning to the end are the first shoulder (10), the second shoulder (11), the third shoulder (12) and the fourth shoulder (13); The contact surfaces of the first shoulder (10), the second shoulder (11), the third shoulder (12) and the fourth shoulder (13) with the bushing (2) are provided with equalizing grooves (9) along the circumferential direction; the throttling grooves (15) on the first shoulder (10) and the third shoulder (12) have the same phase distribution, and the throttling grooves (15) on the second shoulder (11) and the fourth shoulder (13) have the same phase distribution.

3. The oscillating rotary valve for stabilizing throttling pressure according to claim 2, characterized in that: The windows provided on the valve sleeve (2) from the power end to the end include a first window (17), a second window (19), a third window (20) and a fourth window (21), which can be radially aligned with the first shoulder (10), the second shoulder (11), the third shoulder (12) and the fourth shoulder (13) respectively by rotating the valve sleeve (2) relative to the valve core (3).

4. The oscillating rotary valve for stabilizing throttling orifice pressure according to claim 3, characterized in that: The oil ports provided on the valve body (1) include a first oil drain port (23), a first working port (24), an oil inlet port (25), a second working port (26), and a second oil drain port (27); the first oil drain port (23) is connected to the first window (17) to form valve cavity P, the first working port (24) is connected to the second window (19) to form valve cavity (T1), the oil inlet port (25) is connected to the third window (20) to form valve cavity T2, the second working port (26) is connected to the fourth window (21) to form valve cavity A, and the second oil drain port (27) is connected to the waist-shaped hole (22) to form valve cavity B.

5. The oscillating rotary valve for stabilizing throttling pressure according to claim 1, characterized in that: The power ring (7) is provided with a pin hole (8), which is connected to the output end of an external motor through a connector.

6. The oscillating rotary valve for stabilizing throttling pressure according to claim 1, characterized in that: The window is T-shaped and consists of an axial arm and a circumferential arm. The circumferential arm is connected to the power end of the axial arm and is evenly divided by the central axis of the axial arm. The two circumferential sides of the axial arm are either arc-shaped or wedge-shaped, each composed of sides of equal length. The shape of the pre-opening 14 is any one of arc, triangle, U-shape, or trapezoid.

7. The oscillating rotary valve for stabilizing throttling orifice pressure according to claim 1, characterized in that: A groove (18) is provided between adjacent windows on the outer side of the valve sleeve (2), and a sealing ring is provided in the groove (18).

8. The oscillating rotary valve for stabilizing throttling pressure according to claim 1, characterized in that: The end of the support ring (16) is connected to a plug (4), and the end of the valve sleeve (2) is connected to an end cap. The plug is rotatably connected to the end cap (6) via a bearing (5).

9. The shoulder of the vibrating rotary valve for stabilizing throttling pressure according to claim 1, characterized in that: The shoulder is uniformly provided with several throttling grooves (15) along the circumference. Pre-openings (14) are provided on both sides of the circumference of the throttling grooves (15). The side of the pre-opening (14) close to the valve core is sealed with the bottom of the groove (141). The shape of the pre-opening (14) is any one of arc, triangle, U-shape, and trapezoid.

10. The bushing of the vibrating rotary valve for stabilizing throttling pressure according to claim 1, characterized in that: The bushing (2) has several flush windows and a waist-shaped hole (22) from the power end to the end. The windows can be radially superimposed with the throttling groove (15) of the valve core (3) by the rotation of the external valve core (3) relative to the valve sleeve (2) to form a variable throttling orifice. The waist-shaped hole (22) connects to the inner cavity of the valve sleeve (2) to form a return oil channel. The window is T-shaped and consists of an axial arm and a circumferential arm. The circumferential arm is connected to the power end of the axial arm and is evenly divided by the central axis of the axial arm. The two circumferential sides of the axial arm are arc-shaped or wedge-shaped with equal sides.

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