A pressure-inducing chamber structure for a sensor for suppressing water hammer pressure peak

Abstract

The present invention discloses a pressure-inducing chamber structure for a sensor for suppressing a water hammer pressure peak, comprising: a sealing ring, a labyrinth plug, a sealing gasket and a side cover; one end of the labyrinth plug is shaped with a sensitive element, and the other end is pressed by the side cover, and the labyrinth plug and the side cover are sealed by a sealing gasket, and the labyrinth plug and the sensitive element are sealed by a sealing ring, so that a pressure-inducing chamber is formed between the sealing ring, the labyrinth plug and the sensitive element; wherein a labyrinth-shaped flow channel is provided on the end surface of the end where the labyrinth plug and the sealing gasket are butted against each other, and the labyrinth-shaped flow channel is connected with the pressure-inducing chamber through a drainage hole provided in the labyrinth plug.

Description

Technical Field

[0001] The invention relates to the technical field of pipeline systems, and in particular to a pressure-inducing chamber structure for a sensor capable of suppressing a water hammer pressure peak. Background Art

[0002] Circulation pumps and valves are essential components of liquid pipeline systems (pipelines for short). When the circulation pump in the pipeline is started and shut down, and when the electromagnetic valve (located in the pipeline) is transiently opened and closed, or even when the pipeline is experiencing mechanical environments such as vibration and impact, water hammer effect will be produced on the medium in the pipeline. In severe cases, the maximum bursting pressure generated by the water hammer effect may cause damage or even destruction to the fluid circuit equipment and pipeline sealing joints in the pipeline, and in severe cases, it may cause leakage of the fluid circuit, thereby causing catastrophic accidents in the pipeline.

[0003] As an indispensable detection element in pipelines, sensors are widely used in civil and aerospace fields. Sensors sense pressure changes and fluctuations in pipelines through their sensitive elements. In order to improve measurement accuracy, sensitive elements are usually designed to be very precise, but precise sensitive elements are usually relatively weak. Taking the current pressure sensor as an example, the corrugated diaphragm of its sensitive core (i.e., sensitive element) is usually only 0.025mm, and the silicon chip (a sensitive element) of the orifice plate differential pressure sensor or flow sensor is only 0.03mm. When the valve in the pipeline is activated or subjected to mechanical environments such as impact and vibration, the water hammer pressure or pressure difference generated can reach several MPa, far exceeding the tolerance of the sensitive element, resulting in sensor damage.

[0004] Current civil sensors usually use a coil method to attenuate the peak water hammer pressure in the measured pipeline. However, the main problems of the coil-type water hammer pressure peak attenuation method are:

[0005] 1) It takes up a large space and is not convenient for use in places with high size restrictions, such as spacecraft or integrated test components;

[0006] 2) The attenuation of the water hammer pressure peak can only be achieved by increasing the length of the flow channel, but the effect is poor. Usually, the attenuation of the water hammer pressure peak can only reach about 15-20% of the case where no attenuation measures are taken.

[0007] In summary, in order to reduce the damage to the sensor's sensitive elements caused by the water hammer pressure peak generated by valve action, mechanical vibration, etc., it is necessary to propose a sensor pressure induction chamber structure that suppresses the water hammer pressure peak. Summary of the invention

[0008] In view of this, the present invention provides a pressure-inducing chamber structure for a sensor that suppresses water hammer pressure peaks, which can reduce pipeline water hammer pressure peaks generated by valve action, mechanical vibration, etc., and protect sensitive elements of the sensor in the pipeline from damage.

[0009] The technical solution of the present invention is: a pressure-inducing chamber structure for a sensor that suppresses water hammer pressure peaks, comprising: a sealing ring, a labyrinth plug, a sealing gasket and a side cover; one end of the labyrinth plug is shaped with a sensitive element, and the other end is pressed by the side cover, and the labyrinth plug and the side cover are sealed by a sealing gasket, and the labyrinth plug and the sensitive element are sealed by a sealing ring, so that a pressure-inducing chamber is formed between the sealing ring, the labyrinth plug and the sensitive element; wherein a labyrinth-type flow channel is provided on the end face of the end where the labyrinth plug is butted against the sealing gasket, and the labyrinth-type flow channel is connected to the pressure-inducing chamber through a drainage hole provided in the labyrinth plug.

[0010] Preferably, the sensitive element is a cylindrical structure with circular grooves at both axial ends, and the two labyrinth plugs are both stepped columnar structures, and the small ends of the two labyrinth plugs are correspondingly placed in the circular grooves at the axial ends of the sensitive element.

[0011] Preferably, a strip groove I is radially opened at the large end of the labyrinth plug as the entrance of the labyrinth-type flow channel; 3 to 6 circles of drainage channels interconnected with each other are arranged on the end face of the large end of the labyrinth plug, and one end of the drainage channel is connected to the strip groove I and the other end is connected to the drainage hole.

[0012] Preferably, the large end face of the labyrinth plug is provided with an annular groove I, a strip groove II, annular groove II, strip groove III, annular groove III, strip groove IV, annular groove IV and strip groove V which are connected in series in sequence, and the annular groove I is connected with the strip groove I, the strip groove V is connected with the drainage hole, the strip groove I, the strip groove II, the strip groove III, the strip groove IV and the strip groove V are located in the same radial direction, and the annular groove I, the annular groove II, the annular groove III and the annular groove IV are coaxial.

[0013] Preferably, the drainage hole is "T"-shaped, the vertical section of the hole is located at the central axis of the labyrinth plug, one end of which is connected to the strip groove V, and the other end is connected to the two horizontal sections of the "T"-shaped drainage hole, and the two horizontal sections of the "T"-shaped drainage hole are both connected to the pressure-inducing chamber.

[0014] Preferably, the cross section of the labyrinth flow channel along the axial direction of the labyrinth plug is a rectangular cross section with a cross section width of 0.8 to 1.5 mm and an aspect ratio of 1 to 2.

[0015] Preferably, the ratio of the diameter of the drainage hole to the width of the labyrinth-shaped flow channel is 1.2 to 1.6.

[0016] Preferably, the volume of the pressure-inducing chamber is 0.8 ml.

[0017] Beneficial effects:

[0018] (1) First, the present invention is arranged in a conventional pressure induction chamber of a sensor. Compared with an external coil, the pressure induction chamber has a compact structure and saves space. Second, the labyrinth flow channel arranged in the present invention increases the flow resistance of the fluid in the pipeline and reduces the water hammer pressure peak of the pipeline. Third, the sealing gasket arranged between the labyrinth plug and the side cover of the present invention can not only ensure the mutual sealing between the flow channels in the labyrinth flow channel, but also absorb and filter the water hammer pressure peak in the labyrinth flow channel by utilizing the elastic characteristics of the sealing gasket. Fourth, the sealing ring arranged between the labyrinth plug and the sensitive element of the present invention can effectively prevent the water hammer pressure from short-circuiting. Fifth, the shaping design between the shape of the labyrinth plug and the sensitive element in the present invention effectively ensures the coordination between the labyrinth plug and the sensitive element, so that the labyrinth plug fits the pressure sensing surface of the sensitive element as much as possible, while effectively reducing the volume of the pressure induction chamber and reducing the energy of the pressure peak.

[0019] (2) The present invention aims at the specific structural form of the sensitive element, and symmetrically arranges two labyrinth plugs at both ends of the axial direction, which plays a role of redundant backup and prevents clogging by unnecessary objects; and both labyrinth plugs are stepped columnar structures, which can not only accurately shape the sensitive element, but also effectively reduce the volume of the pressure-inducing chamber. At the same time, it is convenient to design a labyrinth-type flow channel to increase the flow resistance of the fluid in the pipeline and reduce the peak water hammer pressure of the pipeline.

[0020] (3) The specific design of the labyrinth-shaped flow channel in the present invention, on the one hand, facilitates the introduction of the liquid in the measured pipeline into the pressure induction chamber; on the other hand, 3 to 6 circles of interconnected drainage channels are provided to extend the flow channel within a limited space, effectively increasing the flow resistance along the fluid in the pipeline and reducing the peak water hammer pressure of the pipeline.

[0021] (4) The labyrinth-shaped flow channel of the present invention is provided with four circles of annular grooves, which increases the length of the pressure-inducing flow channel from the original 10 mm to 80 mm, significantly increases the flow resistance along the fluid in the pipeline, and reduces the peak water hammer pressure of the pipeline.

[0022] (5) The center of the labyrinth plug in the present invention adopts a "T"-shaped drainage hole design to prevent water hammer pressure from directly impacting the sensitive components. The labyrinth flow channel is combined with the "T"-shaped drainage hole throttling, and the sealing gasket made of elastic rubber is used for filtration. The peak value of water hammer pressure can be reduced by more than 80%, thereby effectively protecting the sensitive components of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the structure of the pressure chamber of the present invention, wherein a dual-channel sensor is taken as an example, H is the high-pressure side, and L is the low-pressure side.

[0024] Figure 2 It is a left (or right) view of the labyrinth plug of the present invention.

[0025] Figure 3 It is a front cross-sectional view of the labyrinth plug in the present invention.

[0026] Among them, 1-sensitive element, 2-sealing ring, 3-labyrinth plug, 4-sealing gasket, 5-side cover. DETAILED DESCRIPTION

[0027] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0028] This embodiment provides a pressure-inducing chamber structure for a sensor that suppresses water hammer pressure peaks, which can reduce pipeline water hammer pressure peaks generated by valve action, mechanical vibration, etc., and protect sensitive elements of the sensor in the pipeline from damage.

[0029] like Figure 1 As shown, the pressure induction chamber structure includes: a sealing ring 2, a labyrinth plug 3, a sealing gasket 4 and a side cover 5; one end of the labyrinth plug 3 is shaped with the sensitive element 1 of the sensor, and the other end is pressed by the side cover 5, and the labyrinth plug 3 and the side cover 5 are sealed by the sealing gasket 4, and the labyrinth plug 3 and the sensitive element 1 are sealed by the sealing ring 2, so that a pressure induction chamber (whose volume can be controlled to 0.8ml) is formed between the sealing ring 2, the labyrinth plug 3 and the sensitive element 1; wherein, a labyrinth-type flow channel is provided on the end face of the end where the labyrinth plug 3 and the sealing gasket 4 are connected, and the labyrinth-type flow channel is connected with the pressure induction chamber through the drainage hole provided in the labyrinth plug 3, so that the liquid entering the measured pipeline can be introduced into the pressure induction chamber.

[0030] In this embodiment, the channel through which the liquid flows from flowing into the labyrinth-shaped flow channel to flowing out from the drainage hole is the pressure-drawing flow channel.

[0031] In this embodiment, the sensitive element 1 is a cylindrical structure with circular grooves at both axial ends. Correspondingly, the two labyrinth plugs 3 are both stepped columnar structures. The small ends of the two labyrinth plugs 3 are correspondingly placed in the circular grooves at the axial ends of the sensitive element 1, and the large ends are pressed by the side covers 5; wherein the diameter of the labyrinth plug 3 gradually increases from one end to the other.

[0032] In this embodiment, Figure 2As shown, the large end of the labyrinth plug 3 is provided with a strip groove I in the radial direction as the entrance of the labyrinth flow channel, and then 3 to 6 circles of mutually connected drainage channels are arranged on the large end face of the labyrinth plug 3 (preferably, 4 circles of mutually connected drainage channels are arranged on the large end face of the labyrinth plug 3, that is, annular groove I, strip groove II, annular groove II, strip groove III, annular groove III, strip groove IV, annular groove IV and strip groove V are arranged in series, and the annular groove I is connected to the strip groove I, and the strip groove V is connected to the strip groove V. Groove V is connected with the drainage hole, strip groove I, strip groove II, strip groove III, strip groove IV and strip groove V are located in the same radial direction, annular groove I, annular groove II, annular groove III and annular groove IV are coaxial, and at the same time, annular groove I, annular groove II, annular groove III and annular groove IV are connected in series and progressively from outside to inside along the radial direction of the large end of the labyrinth plug 3, and are bilaterally symmetrical about the radial direction where strip groove I, strip groove II, strip groove III, strip groove IV and strip groove V are located); Figure 3 As shown, a "T"-shaped drainage hole is provided at the center of the labyrinth plug 3. The vertical section of the hole is located at the central axis of the labyrinth plug 3, one end of which is connected to the strip groove V, and the other end is connected to the two horizontal sections of the "T"-shaped drainage hole. At the same time, the two horizontal sections of the "T"-shaped drainage hole are both connected to the pressure-inducing chamber; wherein, the strip groove I and the interconnected drainage channels together constitute a labyrinth-type flow channel.

[0033] In this embodiment, the cross section of the labyrinth flow channel along the axial direction of the labyrinth plug 3 is a rectangular cross section, the cross section width (ie, the groove width of the labyrinth flow channel) is 0.8 to 1.5 mm (preferably 1 mm), and the aspect ratio is 1 to 2 (preferably 1).

[0034] In this embodiment, the maximum outer diameter of the labyrinth plug 3 is 20 mm, and the minimum outer diameter is 10 mm.

[0035] In this embodiment, the three sections of the "T"-shaped drainage hole have the same aperture, and the ratio of the aperture of the "T"-shaped drainage hole to the groove width of the labyrinth-shaped flow channel is 1.2 to 1.6 (preferably 1.5).

[0036] In this embodiment, the sealing gasket 4 is made of rubber material with a thickness of 1 mm and a Shore hardness of 75.

[0037] The assembly of the pressure chamber structure is as follows:

[0038] 1) First, a sealing ring 2 is installed on the radially opposite sides of the sensitive element 1, and then two labyrinth plugs 3 are symmetrically pressed on the axial ends of the sensitive element 1, that is, the small end of each sensitive element 1 is shaped with the circular groove of the labyrinth plug 3; wherein, the sealing ring 2 clamped between the labyrinth plug 3 and the sensitive element 1 can prevent the liquid from short-circuiting and directly entering the side where the sensitive element 1 is located (that is, the pressure induction chamber), and ensure that the liquid enters the pressure induction chamber through the labyrinth flow channel and the "T"-shaped drainage hole in the labyrinth plug 3;

[0039] 2) After installing the labyrinth plug 3, install a sealing gasket 4 on the large end face of each labyrinth plug 3, and finally press the sealing gasket 4 onto the labyrinth plug 3 through the side cover 5; wherein the sealing gasket 4 can ensure the mutual isolation between the multiple circles of drainage channels on the labyrinth plug 3.

[0040] The pressure induction chamber structure of the differential pressure sensor designed according to the present invention passed the 1200g shock response spectrum and 21grm root mean square accelerated random vibration tests, and reduced the peak water hammer pressure of the shock and vibration tests from 3MPa to 300kPa, a reduction of 90%, effectively protecting the sensitive element 1 of the sensor.

[0041] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A pressure induction chamber structure for a sensor for suppressing water hammer pressure peak, characterized in that: include: A sealing ring (2), a labyrinth plug (3), a sealing gasket (4) and a side cover (5); one end of the labyrinth plug (3) is shaped with the sensitive element (1), and the other end is pressed by the side cover (5), and the labyrinth plug (3) and the side cover (5) are sealed by the sealing gasket (4), and the labyrinth plug (3) and the sensitive element (1) are sealed by the sealing ring (2), so that a pressure-inducing cavity is formed between the sealing ring (2), the labyrinth plug (3) and the sensitive element (1); wherein a labyrinth-shaped flow channel is provided on the end surface of the end where the labyrinth plug (3) and the sealing gasket (4) are butt-jointed, and the labyrinth-shaped flow channel is connected to the pressure-inducing cavity through a drainage hole provided in the labyrinth plug (3); The sensitive element (1) is a cylindrical structure with circular grooves at both axial ends, and the two labyrinth plugs (3) are both stepped columnar structures, with the small ends of the two labyrinth plugs (3) correspondingly placed in the circular grooves at the axial ends of the sensitive element (1); The drainage hole is in a "T" shape, and the vertical section of the hole is located at the central axis of the labyrinth plug (3), one end of which is connected to the strip groove V, and the other end is connected to two horizontal sections of the "T"-shaped drainage hole, and the two horizontal sections of the "T"-shaped drainage hole are both connected to the pressure induction chamber.

2. The pressure induction chamber structure for a sensor for suppressing water hammer pressure peak according to claim 1, characterized in that: The large end of the labyrinth plug (3) is provided with a strip groove I in the radial direction, serving as the entrance of the labyrinth-type flow channel; 3 to 6 circles of drainage channels that are interconnected are arranged on the large end surface of the labyrinth plug (3), and one end of the drainage channel is connected to the strip groove I, and the other end is connected to the drainage hole.

3. The pressure induction chamber structure for a sensor for suppressing water hammer pressure peak according to claim 2, characterized in that: The large end surface of the labyrinth plug (3) is provided with an annular groove I, a strip groove II, annular groove II, strip groove III, annular groove III, strip groove IV, annular groove IV and strip groove V which are connected in series in sequence, and the annular groove I is connected with the strip groove I, and the strip groove V is connected with the drainage hole, and the strip grooves I, II, III, IV and V are located in the same radial direction, and the annular grooves I, II, III and IV are coaxial.

4. The pressure induction chamber structure for a sensor for suppressing water hammer pressure peak according to any one of claims 1 to 3, characterized in that: The cross section of the labyrinth-shaped flow channel along the axial direction of the labyrinth plug (3) is a rectangular cross section, the cross section width is 0.8-1.5 mm, and the aspect ratio is 1-2.

5. The pressure induction chamber structure for a sensor for suppressing water hammer pressure peak according to claim 4, characterized in that: The ratio of the aperture of the drainage hole to the groove width of the labyrinth-shaped flow channel is 1.2-1.

6.

6. The pressure induction chamber structure for a sensor for suppressing water hammer pressure peak according to any one of claims 1 to 3, characterized in that: The volume of the pressure-inducing chamber is 0.8 ml.

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