Sanding device

Abstract

The invention relates to a sanding device, and belongs to the technical field of railway vehicle sanding. The sanding device comprises a mechanical locking mechanism and a sanding execution mechanism, the mechanical locking mechanism comprises a valve body, and the valve body is provided with an inner cavity and a sand inlet communicated with the inner cavity; a spring; the piston is slidably and hermetically arranged in the inner cavity and reciprocates along the axis of the inner cavity; a piston air cavity is formed between the end cover and the piston; the end, away from the piston, of the valve rod is provided with an end head, the end head is provided with a valve rod shrinkage plug, and the valve rod shrinkage plug is communicated with the piston air cavity. Sand grains are conveyed downwards through rotation of the impeller shaft, and directional conveying of the sand grains from the upstream end to the downstream end of a cavity of the impeller shaft is achieved by means of contact and pushing of the impeller and the sand grains; when compressed air is injected into the piston air cavity to separate the end head from the impeller shaft cavity, air can be injected into the impeller shaft cavity through the shrinkage plug of the valve rod to push sand grains to flow, linkage of sealing and sand grain conveying is achieved, and it is guaranteed that sanding operation is carried out orderly.

Description

Technical Field

[0001] This application relates to the field of sand spreading technology for rail vehicles, and more particularly to a sand spreading device. Background Technology

[0002] Wheel slippage is difficult to completely avoid during rail vehicle operation, especially in adverse weather conditions such as rain and snow, when the coefficient of friction between the wheel and rail decreases significantly, making slippage more likely. Wheel slippage not only causes direct abrasion between the wheel tread and the rail, affecting the service life of the vehicle and the track, but more seriously, it greatly increases the vehicle's braking distance, undermines driving stability, and can even lead to major safety accidents such as derailment and collisions, posing a serious threat to the safety and reliability of rail transportation.

[0003] To address wheel slippage, the most common and effective solution in the industry is to equip rail vehicles with sand-spreading devices. These devices spread sand onto the wheel-rail contact interface, increasing the friction coefficient between the wheel and rail, thus suppressing slippage. In the field of high-speed trains, the core functional component of the sand-spreading system is often a differential pressure sand-spreading unit. This unit mainly consists of key components such as an air circuit board, a sand baffle plate, a sand flow pipe, and a sand bell cap. Its working principle is to utilize the driving force generated by the air pressure difference to transport sand from the sand box to the wheel-rail contact area, completing the sand-spreading operation.

[0004] However, existing differential pressure sand spreading units have significant technical shortcomings in practical applications, making it difficult to meet the high requirements of rail vehicles for sand spreading accuracy and stability. On the one hand, the sand spreading amount of this type of sand spreading unit cannot be dynamically adjusted according to the real-time train speed, resulting in insufficient sand spreading when the train is running at high speed, making it difficult to effectively improve wheel-rail adhesion. On the other hand, excessive sand spreading at low speed results in sand waste and may also cause derivative problems such as environmental pollution and track sand accumulation. On the other hand, the sand spreading amount is greatly affected by external factors such as sand particle size and humidity. When the sand becomes damp and clumps, it will directly cause fluctuations in the sand spreading amount, further reducing the overall reliability of the sand spreading system. Summary of the Invention

[0005] This application provides a sand spreading device, the purpose of which is to precisely control the amount of sand spread by controlling the impeller shaft speed, and at the same time to seal the sand box from the outside world by using a mechanical locking mechanism to prevent moisture from entering the sand box and causing the sand to become damp; it solves the problems of existing sand spreading devices being unable to control the amount of sand spread according to the train speed and being easily affected by external factors, and meets the needs of industry users for stable sand spreading and continuously adjustable sand spreading.

[0006] To achieve the above objectives, this application adopts the following technical solution: This application provides a sand-spreading device, including a mechanical locking mechanism and a sand-spreading actuator connected to the mechanical locking mechanism; wherein, the mechanical locking mechanism includes: The valve body has an inner cavity and a sand inlet communicating with the inner cavity; A spring, which is disposed in the inner cavity and on the side away from the sand-spreading actuator; A piston is slidably and sealed within the inner cavity and reciprocates along the axis of the inner cavity. The piston is located on the side of the spring near the sand-spraying actuator and is connected to the spring. The portion of the inner cavity located on the side of the piston facing the spring is a spring air chamber. An end cap is sealed and fixed in the inner cavity and disposed between the sand inlet and the piston. The portion of the inner cavity located between the end cap and the piston is a piston air chamber. A through hole is provided on the end cap. A valve stem is connected to the piston and slidably seals through the through hole. The valve stem has an end near the sand-spreading actuator and a valve stem plug is provided on the side of the end near the sand-spreading actuator. The valve stem plug communicates with the piston air chamber. The sand-spreading actuator includes: Impeller shaft cavity, the impeller shaft cavity being connected to the sand inlet; An impeller shaft is rotatably disposed within the impeller shaft cavity; When the air pressure in the piston chamber is less than the sum of the air pressure in the spring chamber and the thrust of the spring, the thrust of the spring acts on the piston, thereby pushing the end to seal against the side of the impeller shaft cavity near the mechanical locking mechanism; when the air pressure in the piston chamber is greater than the sum of the air pressure in the spring chamber and the thrust of the spring, the piston moves away from the sand-spreading actuator, causing the end to separate from the impeller shaft cavity; sand particles enter the inner cavity from the sand inlet, and part of the compressed air in the piston chamber is ejected from the valve stem constriction, pushing the sand particles into the impeller shaft cavity, and the impeller shaft conveys the sand particles in the sand particle outflow direction.

[0007] In the above embodiments, this application conveys sand particles downwards by rotating the impeller shaft. Through the contact and pushing between the impeller and the sand particles, the sand particles are directionally transported from the upstream end to the downstream end of the impeller shaft cavity. In addition, this application achieves sealing and separation between the end and the impeller shaft cavity by cooperating with the change of air pressure in the piston air chamber in the mechanical locking mechanism and the spring thrust, effectively isolating the sand box from the atmosphere. Therefore, the sand spreading unit does not require drying air or heating rods. Furthermore, while injecting compressed air into the piston air chamber to separate the end from the impeller shaft cavity, the air can be sprayed into the impeller shaft cavity through the valve stem compression to push the sand particles to flow, realizing the linkage between sealing and sand particle conveying, and ensuring that the sand spreading operation is carried out in an orderly manner.

[0008] In some embodiments, the inner cavity extends along the axis of the valve body, an adjusting element is provided on the side of the inner cavity away from the sand-spreading actuator, and a cover plate is sealed on the end of the valve body away from the sand-spreading actuator; The adjusting member abuts against the side of the spring away from the piston, and the adjusting member can reciprocate along the axis of the inner cavity.

[0009] In the above embodiments, this application improves the compression of the spring by setting an adjusting member connected to the spring, which moves towards the piston, thereby adjusting the valve stem's movement range to control the opening degree of the end, and finally achieving the adjustment of the sand spreading amount to meet the sand spreading requirements under different working conditions.

[0010] In some embodiments, the sand-spreading actuator includes a sand-spreading body, which is sealed to the valve body and located downstream of the valve body in the direction of sand flow; the impeller shaft cavity is disposed within the sand-spreading body and extends through it in the direction of sand flow, and the impeller shaft cavity communicates with the inner cavity.

[0011] In the above embodiments, this application introduces the sand-spreading body and clarifies its sealing connection with the valve body, as well as the position of the sand-spreading body at the downstream end of the sand flow direction of the valve body. At the same time, the impeller shaft cavity is set in the sand-spreading body and communicates with the inner cavity, providing structural protection for the stable delivery of sand particles to the impeller shaft cavity.

[0012] In some embodiments, a reinforcing sleeve is provided on the inner wall of the impeller shaft cavity, the reinforcing sleeve being used to prevent sand particles from scratching the inner wall of the impeller shaft cavity.

[0013] In the above embodiments, since the sand particles have high hardness, the outer wall of the impeller shaft cavity is easily damaged if it is in direct contact with the sand particles for a long time. Therefore, this application provides a reinforcing sleeve on the outer wall of the impeller shaft cavity. The reinforcing sleeve can effectively improve the hardness of the outer wall of the impeller shaft cavity, avoid damage to the outer wall due to contact friction or impact of sand particles, and extend the service life of the device.

[0014] In some embodiments, a first sealing bearing and a second sealing bearing are provided on both sides of the impeller shaft cavity, the first sealing bearing and the second sealing bearing are coaxial and their axes are perpendicular to the direction of sand flow; the two sides of the impeller shaft are respectively connected to the first sealing bearing and the second sealing bearing; The sand-spreading body is provided with a first bearing seat and a second bearing seat, the first sealed bearing is disposed in the first bearing seat, and the second sealed bearing is disposed in the second bearing seat; The impeller shaft is rotatably sealed at one end near the first sealed bearing, passing through the first bearing housing and connected to the output shaft of the drive unit.

[0015] In the above embodiments, this application clarifies the installation structure of the impeller shaft in the sand-spreading body by setting a coaxial first and second sealed bearing on both sides of the impeller shaft cavity, connecting both sides of the impeller shaft to the two sealed bearings respectively, and installing and fixing the sealed bearings through the first and second bearing seats. The end of the impeller shaft near the first sealed bearing passes through the first bearing seat and connects to the output shaft of the drive component. This ensures stable rotation of the impeller shaft and prevents sand and dust from entering and affecting operation. Furthermore, this application controls the impeller speed and thus the sand-spreading amount through the drive component. The sand-spreading amount can be continuously and dynamically adjusted according to the sand-spreading amount command from upstream of the train, thus effectively improving sand utilization and avoiding insufficient sand spreading at high train speeds, which would fail to achieve the desired adhesion, and excessive sand spreading at low train speeds, which would cause sand waste, environmental pollution, or other side effects.

[0016] In some embodiments, the valve body is provided with a first air passage, which communicates with the piston air chamber; the valve stem is provided with a third air passage, which is used to connect the piston air chamber with the valve stem constriction. The sand-spreading body includes a sand-spreading air inlet and a fourth air passage, the fourth air passage being used to connect the sand-spreading air inlet and the first air passage.

[0017] In the above embodiments, this application provides a first air passage on the valve body that communicates with the piston air chamber, and a fourth air passage on the sand-spreading body that communicates with the sand-spreading air inlet and the first air passage. This makes the first air passage and the fourth air passage form a sand-inlet air passage, which clarifies the path of compressed air into the piston air chamber. This provides an air passage guarantee for establishing air pressure in the piston air chamber to drive the piston to move, and ensures the smooth start of the sand-spreading operation.

[0018] In some embodiments, the valve body is provided with a second air passage, which is connected to the sand inlet. The sand-spreading body is provided with a fifth air passage. One end of the fifth air passage is connected to the sand-spreading air inlet through a compensating air constriction plug, and the other end of the fifth air passage is connected to the second air passage.

[0019] In the above embodiments, this application provides a second air passage on the valve body that is connected to the sand inlet, and a fifth air passage on the sand spreading body, one end of which is connected to the sand spreading air inlet through a compensating air blockage and the other end of which is connected to the second air passage. The second air passage and the fifth air passage form a compensating air passage. The compensating air can disturb the sand particles near the sand inlet through this air passage, assisting the sand particles to smoothly enter the inner cavity and the impeller shaft cavity, thereby improving the smoothness of sand particle transportation.

[0020] In some embodiments, the impeller shaft is provided with a sand flow channel for allowing sand particles to pass through when the impeller shaft stops rotating.

[0021] In the above embodiments, this application provides a sand flow channel (i.e., a safe mode sand flow port) on the impeller shaft. When the impeller shaft stops rotating, sand particles can flow through the sand flow channel to meet the basic sand spreading requirements under conditions such as motor failure and impeller shaft inability to rotate. This ensures that the device can still play a certain sand spreading role under special circumstances and improves operational reliability.

[0022] In some embodiments, a sand blowing seat is provided on the side of the sand spreading body away from the mechanical locking mechanism, and a sand discharge channel is provided through the sand blowing seat along the sand flow direction, and the sand discharge channel is connected to the impeller shaft cavity.

[0023] In the above embodiments, this application provides a sand blowing seat on the side of the sand spreading body away from the mechanical locking mechanism, and provides a sand discharge channel communicating with the impeller shaft cavity through the sand discharge channel along the sand flow direction on the sand blowing seat, providing a discharge path for the sand particles transported downstream by the impeller shaft, controlling the final sand discharge direction, so that the sand particles can flow stably to the wheel-rail contact area, and ensuring the sand spreading effect.

[0024] In some embodiments, the sand blowing base is provided with a sand blowing air passage and a sand blowing air inlet. The sand blowing air passage is connected to the sand blowing air inlet through a sand blowing air constriction, and the sand blowing air passage is connected to the sand discharge channel through a sand blowing air duct.

[0025] In the above embodiments, this application sets a sand blowing air path and a sand blowing air inlet on the sand blowing base, so that the sand blowing air path is connected to the sand blowing air inlet through the sand blowing air constriction, and is connected to the sand discharge channel through the sand blowing air duct. The sand blowing air can enter the sand discharge channel through the air path, push the sand particles to be sprayed out quickly, and at the same time, it can delay the sand blowing after the sand spreading is completed to clean the residual sand particles in the sand discharge channel and avoid the channel blockage.

[0026] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of the sand spreading device provided in the embodiments of this application; Figure 2 This is a schematic diagram showing the separation of the mechanical locking mechanism and the sand spreading actuator of the sand spreading device provided in the embodiments of this application; Figure 3 This is a cross-sectional schematic diagram of the sand spreading device and sand box provided in the embodiments of this application; Figure 4 This is a cross-sectional view of the sand-spreading device provided in the embodiments of this application from another angle; Figure 5 This is a diagram showing the air path distribution of the sand-spreading device provided in the embodiments of this application in a closed state; wherein, the dashed line is the projection of the air path onto the plane containing the cross-section; Figure 6 This is a schematic diagram of the sand-spreading device provided in this application embodiment during operation; wherein, the dashed line is the projection of the air path onto the plane containing the cross-section; Figure 7 This is a schematic diagram of the impeller shaft provided in an embodiment of this application; Figure 8 This is a schematic diagram illustrating the principle of the blockage provided in the embodiments of this application.

[0028] In the above figures: 100, Mechanical locking mechanism; 110, Valve body; 111, Cover plate; 112, First sealing ring; 113, First air passage; 113a, First outlet; 114, Second air passage; 114a, Second outlet; 115, Sand inlet; 116, Piston air chamber; 117, Spring air chamber; 120, Adjusting component; 130, Spring; 140, Valve stem; 141, Third air passage; 142, End; 142a, Valve core sealing ring; 142b, Valve stem plug; 150, Piston; 151, Sealing gasket; 152, First anti-wear ring; 153, Second sealing ring; 160, End cap; 161, Set screw; 162, Third sealing ring; 163, Second anti-wear ring; 164, Fourth sealing ring; 200, Sand spreading actuator; 2 10. Sand-spreading body; 211. Impeller shaft cavity; 211a. Reinforcing sleeve; 212. Sand-spreading air inlet; 212a. Compensating air constriction block; 213. Fourth air passage; 214. Fifth air passage; 220. First bearing housing; 221. Fifth sealing ring; 222. Dynamic sealing ring; 223. First sealing bearing; 230. Second bearing housing; 231. Sixth sealing ring; 232. Second sealing bearing; 240. Impeller shaft; 241. Impeller; 242. Sand flow channel; 250. Drive component; 260. Sand-blowing seat; 261. Seventh sealing ring; 262. Sand discharge channel; 263. Sand-blowing air passage; 263a. Sand-blowing air inlet; 263b. Sand-blowing air duct; 163c. Sand-blowing air constriction block; 300. Sealing gasket; 400. Sand box; 500. Sand particles. Detailed Implementation

[0029] In the description of this application, 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", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. In this application, unless otherwise expressly 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 components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0030] In this application, unless otherwise expressly 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," "on top of," and "over" 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.

[0031] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. 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.

[0032] Additionally, if the meaning of "and / or" in the text is that it includes three parallel options, taking "A and / or B" as an example, it includes option A, option B, or an option that satisfies both A and B.

[0033] The present application will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.

[0034] The performance of existing sand-spreading systems is mainly determined by the sand-spreading unit. High-speed trains often use differential pressure sand-spreading units, which include components such as air circuit plates, sand baffles, sand flow pipes, and sand bell caps. They utilize air pressure to generate a pressure difference to perform the sand-spreading operation. However, this type of sand-spreading unit has drawbacks such as the inability to dynamically adjust the sand-spreading amount according to train speed and low sand-spreading accuracy. Furthermore, this type of sand-spreading unit is affected by factors such as sand particle size and environmental humidity, which may lead to unstable sand-spreading amounts and significant differences in performance between different units.

[0035] Based on this, this application proposes a sand-spreading device that uses a motor-driven sand supply mechanism. The sand-spreading function is controlled by adjusting the rotational speed of the driving component. The motor speed is adjusted according to the sand-spreading command from upstream of the train, continuously and dynamically adjusting the sand-spreading amount. This effectively improves sand utilization and avoids insufficient sand spreading at high train speeds, which fails to achieve the desired adhesion, and excessive sand spreading at low train speeds, which leads to sand waste, environmental pollution, or other side effects. Furthermore, the device utilizes a mechanical locking mechanism 100 to achieve a sealing function, effectively isolating the sand box 400 from the atmosphere. Therefore, the sand-spreading unit does not require drying air or heating rods. Additionally, an independent sand-blowing air path allows for delayed sand blowing, ensuring that no sand residue remains in the sand-spreading pipe after each application, achieving a sand-cleaning function.

[0036] In the following, embodiments of this application will be described in detail with reference to the accompanying drawings.

[0037] As attached Figures 1 to 8 As shown in an illustrative embodiment of this application, the sand-spreading device includes a mechanical locking mechanism 100 and a sand-spreading actuator 200 connected to the mechanical locking mechanism 100.

[0038] It is worth noting that, in order to clearly describe the relative positional relationship of each component, this application defines the direction as follows: the direction in which the sand particles 500 of the sand-spreading device flow out is taken as the "downward" direction of each component, and the direction opposite to the "downward" direction is taken as the "upward" direction of each component. That is to say, in this application, the mechanical locking mechanism 100 is located above the sand-spreading actuator 200.

[0039] In some embodiments, such as Figures 2-4 As shown, the mechanical locking mechanism 100 includes a valve body 110, which has an inner cavity and a sand inlet 115 communicating with the inner cavity. The sand inlet 115 is used to connect the sand box 400 with the inner cavity.

[0040] In some embodiments, such as Figure 3 As shown, the mechanical locking mechanism 100 is vertically installed at the bottom of the sand box 400, and the sand inlet 115 is connected to the sand box 400.

[0041] In some embodiments, the mechanical locking mechanism 100 is axially and horizontally installed at the bottom of the sand box 400, and the sand inlet 115 is connected to the sand box 400.

[0042] It is worth noting that, in order to better demonstrate the structure and installation position of this application, this application and its accompanying drawings take the mechanical locking mechanism 100 being vertically installed axially at the bottom of the sand box 400 as an example, but this does not mean that this application can only be arranged in this way.

[0043] In some embodiments, the sand inlet 115 is disposed at an angle downward; specifically, the axis of the sand inlet 115 forms an acute angle with the plane perpendicular to the axis of the inner cavity, and the direction vector along the axis of the sand inlet 115 from the outside to the inside of the inner cavity is projected onto the sand-spreading actuator 200 in the direction of sand particle 500 outflow.

[0044] In some embodiments, the angle between the axis of the sand inlet 115 and the plane perpendicular to the axis of the inner cavity is 15°. If the angle is less than 15°, the inclination of the sand inlet 115 is too small, and its axis is closer to horizontal (i.e., closer to the vertical plane of the axis of the inner cavity). In this case, after the compensating air enters from the sand inlet 115, the airflow direction deviates little from the path of the sand particles 500 outflow direction, making it difficult to generate sufficient disturbance thrust to push the sand particles 500 to flow quickly into the inner cavity and the impeller shaft cavity 211.

[0045] In some embodiments, the angle between the axis of the sand inlet 115 and the plane perpendicular to the axis of the inner cavity is 60°. If the angle is greater than 60°, the inclination of the sand inlet 115 is too large, and its axis is closer to vertically downward (i.e., the direction of sand particle 500 outflow). In this case, after the compensating air enters the sand inlet 115, the airflow direction is excessively deflected downward, and most of the airflow will directly rush to the bottom of the inner cavity or the impeller shaft cavity 211, making it difficult to form a stable disturbance area near the sand inlet 115.

[0046] In some embodiments, the angle between the axis of the sand inlet 115 and the plane perpendicular to the axis of the inner cavity is 15° to 60°, so as to achieve rapid sand intake under the action of compensating wind.

[0047] In some embodiments, the angle between the axis of the sand inlet 115 and the plane perpendicular to the axis of the inner cavity is 45°.

[0048] In some embodiments, the number of sand inlets 115 is at least one.

[0049] In some embodiments, the number of sand inlets 115 is four, and the four sand inlets 115 are arranged axially spaced on the valve body 110.

[0050] In some embodiments, such as Figures 3-4 As shown, the mechanical locking mechanism 100 includes a spring 130, which is disposed in the inner cavity and on the side away from the sand-spraying actuator 200.

[0051] In some embodiments, the mechanical locking mechanism 100 includes a piston 150, which is slidably and sealed in the inner cavity and reciprocates along the axis of the inner cavity. The piston 150 is disposed on the side of the spring 130 near the sand-spraying actuator 200 and is connected to the spring 130. The portion of the inner cavity located on the side of the piston facing the spring is the spring air chamber 117.

[0052] In some embodiments, the spring 130 is mounted on the upper part of the piston 150 and coaxial with the piston 150, and the spring 130 is located in the spring air chamber 117.

[0053] In some embodiments, a second sealing ring 153 is provided around the outer wall of the piston 150 along the axial direction to achieve a sliding sealing connection between the piston 150 and the inner wall of the cavity.

[0054] In some embodiments, the second sealing ring 153 is a Y-shaped sealing ring (referred to as Y-ring), which is a lip-shaped rubber seal with a "Y"-shaped cross-section, which fits tightly against the cover by its open lip.

[0055] In some embodiments, a first anti-wear ring 152 is provided around the outer wall of the piston 150 along the axial direction to realize the anti-wear function of axial movement and extend the service life of the piston 150.

[0056] In some embodiments, the mechanical locking mechanism 100 includes an end cap 160, which is sealed and fixed in the inner cavity and disposed between the sand inlet 115 and the piston 150. The portion of the inner cavity located between the end cap 160 and the piston 150 is the piston air chamber 116, and the end cap 160 is provided with a through hole.

[0057] Specifically, this application can change the air pressure in the piston air chamber 116 by changing the amount of compressed air injected into the piston air chamber 116. The piston 150 can reciprocate along the axis of the inner cavity as the air pressure changes, thereby driving the valve stem 140 to move synchronously to switch between sealing and sand-feeding states.

[0058] In some embodiments, the end cap 160 is fixedly connected to the valve body 110 by a set screw 161.

[0059] In some embodiments, the outer wall of the end cap 160 and the inner wall of the valve body 110 are sealed by a third sealing ring 162.

[0060] Furthermore, the third sealing ring 162 is an O-ring.

[0061] In some embodiments, the mechanical locking mechanism 100 includes a valve stem 140 connected to a piston 150. The valve stem 140 slidably seals the through hole passing through the end cap 160. One end of the valve stem 140 near the sand-spraying actuator 200 is provided with an end head 142. A valve stem constriction plug 142b is provided on the side of the end head 142 near the sand-spraying actuator 200. The valve stem constriction plug 142b communicates with the piston air chamber 116.

[0062] Among them, such as Figure 8 As shown, the valve stem plug 142b has a variable diameter inner hole extending along its axis, with one end of the inner hole having a larger diameter than the other. Specifically, the end of the valve stem plug 142b with a smaller inner diameter is connected to the piston air chamber 116, while the end with a larger diameter faces the impeller shaft cavity 211, thereby achieving the function of flow restriction and flow distribution. Based on this, by replacing the valve stem plug 142b with different inner hole diameter parameters, the airflow through the plug can be flexibly adjusted, thereby achieving precise control of the airflow distribution between the piston air chamber 116 and the impeller shaft cavity 211.

[0063] It is worth noting that the other plugs in this application are similar in structure, principle and function to the valve stem plug 142b, so they will not be described in detail here.

[0064] In some embodiments, the piston 150, end cap 160, and valve stem 140 are coaxial.

[0065] In some embodiments, one end of the valve stem 140 is sealed through the piston 150 and extends a portion away from the piston 150. The piston 150 is mounted on the upper part of the valve stem 140 by a nut and a sealing gasket 151, thus forming a seal. The portion of the valve stem 140 extending out of the piston 150 is inserted into the spring 130 to serve as a guide rod for the spring 130, preventing the spring 130 from shifting or tilting when compressed by the piston 150.

[0066] The sealing gasket 151 is typically a rubber-metal composite gasket (or a polytetrafluoroethylene coated gasket) with an inner hole. One side is pressed against the end face of the piston 150 by a nut, and the other side is press-fitted to the cylindrical surface of the valve stem 140. It serves both as an end face seal (preventing leakage of the internal medium along the valve stem 140) and as a certain auxiliary seal of the stem. The sealing gasket 151 in this application adopts the prior art, and the specific principle and structure will not be described in detail.

[0067] In some embodiments, such as Figure 4 As shown, a fourth sealing ring 164 is circumferentially arranged around the inner wall of the through hole of the end cap 160 to form a sliding seal with the valve stem 140.

[0068] Furthermore, the fourth sealing ring 164 is a Y-type sealing ring.

[0069] In some embodiments, a second anti-wear ring 163 is provided circumferentially around the inner wall of the through hole of the end cap 160 to achieve the anti-wear function of reciprocating axial movement.

[0070] In some embodiments, a valve core sealing ring 142a is axially arranged around the outer wall of the end 142 to better seal the opening of the impeller shaft cavity 211 near the mechanical locking mechanism 100. This application achieves a sealing function by using the thrust of the spring 130 to tightly fit the valve core sealing ring 142a on the end 142 of the valve stem 140 with the sand-spreading body 210, effectively isolating the sand box 400 from the atmosphere. Therefore, the sand-spreading unit does not require drying air or a heating rod.

[0071] In some embodiments, the sand-spreading actuator 200 includes an impeller shaft cavity 211, which is connected to the sand inlet 115.

[0072] In some embodiments, the sand-spraying actuator 200 includes an impeller shaft 240, which is rotatably disposed within the impeller shaft cavity 211.

[0073] When the air pressure in the piston chamber 116 is less than the sum of the air pressure in the spring chamber 117 and the thrust of the spring 130, the thrust of the spring 130 acts on the piston 150, thereby pushing the end 142 to seal against the side of the impeller shaft cavity 211 near the mechanical locking mechanism 100; when the air pressure in the piston chamber 116 is greater than the sum of the air pressure in the spring chamber 117 and the thrust of the spring 130, the piston 150 moves away from the sand-spraying actuator 200, causing the end 142 to separate from the impeller shaft cavity 211; sand particles 500 enter the inner cavity from the sand inlet 115, and part of the compressed air in the piston chamber 116 is ejected from the valve stem constriction 142b, pushing the sand particles 500 into the impeller shaft cavity 211, and the impeller shaft 240 transports the sand particles 500 in the final outflow direction of the sand particles 500 in this application.

[0074] In addition, in order to ensure that the end 142 remains separated from the impeller shaft cavity 211, compressed air needs to be continuously injected into the piston air chamber 116, while ensuring that the amount of gas ejected from the valve stem plug 142b is less than the amount of gas injected into the piston air chamber 116, so as to maintain dynamic balance.

[0075] In the above embodiments, this application conveys sand particles 500 downwards by rotating the impeller shaft 240. Through the contact and pushing action between the impeller 241 and the sand particles 500, the sand particles 500 are directionally transported from the upstream end to the downstream end of the impeller shaft cavity 211. Furthermore, this application achieves a sealed fit or separation between the end 142 and the impeller shaft cavity 211 by coordinating the change in air pressure in the piston air chamber 116 of the mechanical locking mechanism 100 and the thrust of the spring 130, effectively isolating the sand box 400 from the atmosphere. Therefore, the sand spreading unit does not require drying air or a heating rod. In addition, while injecting compressed air into the piston air chamber 116 to separate the end 142 from the impeller shaft cavity 211, the valve stem constriction 142b can simultaneously spray air into the impeller shaft cavity 211 to propel the sand particles 500, achieving a linkage between sealing and sand particle 500 conveying, ensuring the orderly conduct of the sand spreading operation.

[0076] In some embodiments, the inner cavity extends along the axis of the valve body 110, and an adjusting member 120 is provided on the side of the inner cavity away from the sand-spraying actuator 200. The adjusting member 120 can reciprocate along the axis of the inner cavity. A cover plate 111 is sealed at the end of the valve body 110 away from the sand-spraying actuator 200. The adjusting member 120 is disposed between the cover plate 111 and the spring 130. The adjusting member 120 is spaced a certain distance from the valve stem 140 to allow for adjustment space.

[0077] Among them, the cavity located between the cover plate 111 and the piston 150 is the spring air cavity 117, which is a sealed cavity structure.

[0078] In some embodiments, the adjusting member 120 is a bolt, and the inner wall of the inner cavity on the side away from the sand-spraying actuator 200 is provided with an internal thread that matches the bolt. The adjusting member 120 is provided in the valve body 110 through threaded engagement. By rotating the adjusting member 120, the adjusting member 120 can be moved axially along the inner cavity.

[0079] In some embodiments, the cover plate 111 is mounted to the end of the valve body 110 by screws and the first sealing ring 112 to form a seal.

[0080] Furthermore, the first sealing ring 112 is an O-ring.

[0081] In some embodiments, the adjusting member 120 abuts against the side of the spring 130 away from the piston 150; moving the adjusting member 120 toward the piston 150 can increase the compression of the spring 130.

[0082] In the above embodiments, this application provides an adjusting member 120 connected to the spring 130. The adjusting member 120 can be moved towards the piston 150 to increase the compression of the spring 130, thereby adjusting the movement amplitude of the valve stem 140 to control the opening degree of the end 142 (i.e., the vertical distance between the end 142 and the top of the impeller shaft cavity 211), and finally realizes the adjustment of the sand spreading amount to meet the sand spreading requirements under different working conditions.

[0083] In some embodiments, the sand-spreading actuator 200 includes a sand-spreading body 210, which is sealed to the valve body 110 and located at the downstream end of the valve body 110 in the direction of sand particle 500 outflow; the impeller shaft cavity 211 is disposed inside the sand-spreading body 210 and is disposed through the sand particle 500 outflow direction, and the impeller shaft cavity 211 is in communication with the inner cavity.

[0084] In some embodiments, the mechanical locking mechanism 100 is mounted on top of the sand-spraying actuator 200 by screws and a sealing gasket 300 and forms a seal; that is, the sand-spraying body 210 and the valve body 110 are sealed together by the sealing gasket 300.

[0085] In the above embodiments, this application introduces the sand-spreading body 210 and clarifies its sealing connection with the valve body 110, as well as the position of the sand-spreading body 210 at the downstream end of the flow direction of the sand particles 500 in the valve body 110. At the same time, the impeller shaft cavity 211 is set inside the sand-spreading body 210 and communicates with the inner cavity, providing structural protection for the stable delivery of sand particles 500 to the impeller shaft cavity 211.

[0086] In some embodiments, the sand-spraying body 210 is made of aluminum alloy.

[0087] In some embodiments, a reinforcing sleeve 211a is provided on the inner wall of the impeller shaft cavity 211. The reinforcing sleeve 211a is used to prevent sand particles from scratching the inner wall of the impeller shaft cavity 211. Aluminum alloy has relatively low hardness. Without the reinforcing sleeve 211a, sand will be squeezed and flow in the aluminum alloy cavity for a long time, which will easily wear down the parts. Therefore, the reinforcing sleeve 211a is designed to be made of stainless steel or other steel materials with higher hardness to reduce the degree of sand wear on the parts and improve the service life of the sand spreading body 210.

[0088] In the above embodiments, since the sand particles 500 have high hardness, the outer wall of the impeller shaft cavity 211 is easily damaged if it is in direct contact with the sand particles 500 for a long time. Therefore, this application provides a reinforcing sleeve 211a on the outer wall of the impeller shaft cavity 211. The reinforcing sleeve 211a can effectively improve the hardness of the outer wall of the impeller shaft cavity 211, avoid damage to the outer wall due to contact friction or impact of the sand particles 500, and extend the service life of the device.

[0089] In some embodiments, such as Figure 3As shown, a first sealing bearing 223 and a second sealing bearing 232 are provided on both sides of the impeller shaft cavity 211. The first sealing bearing 223 and the second sealing bearing 232 are coaxial, and their axes are perpendicular to the outflow direction of the sand particles 500 in the sand-spreading body 210. The two sides of the impeller shaft 240 are connected to the first sealing bearing 223 and the second sealing bearing 232, respectively. The impeller shaft 240 is axially positioned by the cooperation of its shoulder with the first sealing bearing 223 and the second sealing bearing 232 at both ends.

[0090] In some embodiments, the sand-spreading body 210 is provided with a first bearing seat 220 and a second bearing seat 230, a first sealed bearing 223 is disposed in the first bearing seat 220, and a second sealed bearing 232 is disposed in the second bearing seat 230.

[0091] In some embodiments, the first sealed bearing 223 is installed in the first bearing housing 220 through a transition fit and an interference fit, and the second sealed bearing 232 is installed in the second bearing housing 230 through a transition fit and an interference fit. The transition fit is one of the three standard "hole-shaft" fits in mechanical design, which is between clearance fit and interference fit. In addition, both transition fit and interference fit are existing technologies, and their specific principles and details will not be elaborated here.

[0092] In some embodiments, the first bearing housing 220 is mounted on the sand-spreading body 210 by screws and is sealed by the fifth sealing ring 221, and the second bearing housing 230 is mounted on the sand-spreading body 210 by screws and is sealed by the sixth sealing ring 231.

[0093] Furthermore, both the fifth sealing ring 221 and the sixth sealing ring 231 are O-rings. In some embodiments, one end of the impeller shaft 240 near the first sealed bearing 223 is rotatably sealed through the first bearing housing 220 and connected to the output shaft of the drive member 250.

[0094] In some embodiments, a rotational seal is achieved between the impeller shaft 240 and the first bearing housing 220 via a dynamic seal ring 222. Specifically, the dynamic seal ring 222 is installed on the first bearing housing 220 by an interference fit and simultaneously forms a seal with the outer wall of the impeller shaft 240 to prevent sand and dust from entering the shaft end of the drive component 250.

[0095] In some embodiments, the dynamic sealing ring 222 can be a spring-loaded rotary shaft lip seal, a rubber-coated double-lip rotary seal, or a polytetrafluoroethylene (PTFE) rotary seal, etc.

[0096] In some embodiments, the drive element 250 is a motor.

[0097] Preferably, the drive unit 250 is a servo motor with fault detection and communication interface; in this way, the controller receives the motor's fault information through communication with the motor, which facilitates maintenance.

[0098] In some embodiments, the drive member 250 is mounted to one side of the sand-spraying body 210 by screws.

[0099] In some embodiments, the impeller shaft 240 is coaxial with the output shaft of the drive 250.

[0100] In some embodiments, the impeller shaft 240 and the output shaft of the drive member 250 are connected by a key to transmit torque.

[0101] In some embodiments, this application further includes a controller, which is connected to both the train control console and the motor, and is configured to control the motor speed according to control instructions from the train control console or the train speed read from the train control console.

[0102] It is worth noting that, based on the description of the functions to be achieved in this application, it is obvious to those skilled in the art that the control program inside the controller can be implemented without any creative effort, and therefore the specific details will not be repeated.

[0103] In the above embodiments, this application connects the two sides of the impeller shaft 240 to the two sealed bearings by setting a coaxial first sealed bearing 223 and a second sealed bearing 232 on both sides of the impeller shaft cavity 211. Simultaneously, the sealed bearings are installed and fixed by the first bearing seat 220 and the second bearing seat 230, and the end of the impeller shaft 240 near the first sealed bearing 223 is sealed and passes through the first bearing seat 220 to connect with the output shaft of the drive component 250. This clarifies the installation structure of the impeller shaft 240 in the sand-spreading body 210, ensuring stable rotation of the impeller shaft 240 and preventing sand and dust from entering and affecting operation. Furthermore, this application controls the speed of the impeller 241 and thus the amount of sand spread by controlling the speed of the impeller 241 through the drive component 250. The amount of sand spread can be continuously and dynamically adjusted according to the sand spread command from upstream of the train, thus effectively improving sand utilization and avoiding insufficient sand spread at high train speeds, which would fail to achieve the desired adhesion, and excessive sand spread at low train speeds, which would cause sand waste, environmental pollution, or other side effects.

[0104] In some embodiments, such as Figure 5 , 6 As shown, the valve body 110 is provided with a first air passage 113, which is connected to the piston air chamber 116; the valve stem 140 is provided with a third air passage 141, which is used to connect the piston air chamber 116 and the valve stem constriction 142b.

[0105] In some embodiments, a first outlet 113a is provided on the inner wall of the piston chamber 116, and the first air passage 113 is connected to the piston chamber 116 through the first outlet 113a.

[0106] In some embodiments, the sand-spreading body 210 includes a sand-spreading air inlet 212 and a fourth air passage 213, the fourth air passage 213 being used to connect the sand-spreading air inlet 212 and the first air passage 113. Specifically, when the valve body 110 is assembled onto the sand-spreading body 210, the end of the fourth air passage 213 away from the sand-spreading air inlet 212 is connected to the end of the first air passage 113 near the sand-spreading body 210, thereby achieving communication between the first air passage 113 and the fourth air passage 213.

[0107] To improve the efficiency of air delivery, the connection between the fourth air passage 213 and the first air passage 113 can be sealed by using a sealing ring, gasket, or other materials to achieve a tight seal.

[0108] In the above embodiments, this application provides a first air passage 113 on the valve body 110 that communicates with the piston air chamber 116, and a fourth air passage 213 on the sand-spreading body 210 that communicates with the sand-spreading air inlet 212 and the first air passage 113. This makes the first air passage 113 and the fourth air passage 213 form a sand-inlet air passage, which clarifies the path of compressed air into the piston air chamber 116. This provides an air passage guarantee for establishing air pressure in the piston air chamber 116 to drive the piston 150 to move, and ensures the smooth start of the sand-spreading operation.

[0109] In some embodiments, the valve body 110 is provided with a second air passage 114, which is connected to the sand inlet 115.

[0110] In some embodiments, each sand inlet 115 has a second outlet 114a on its inner wall, and the second air passage 114 is connected to each second outlet 114a through several branches.

[0111] In some embodiments, the sand-spreading body 210 is provided with a fifth air passage 214. One end of the fifth air passage 214 is connected to the sand-spreading air inlet 212 via a compensating air constriction plug 212a, and the other end of the fifth air passage 214 is connected to the second air passage 114. Specifically, when the valve body 110 is assembled onto the sand-spreading body 210, the end of the fifth air passage 214 away from the sand-spreading air inlet 212 is connected to the end of the second air passage 114 near the sand-spreading body 210, thereby achieving communication between the second air passage 114 and the fifth air passage 214.

[0112] To improve the efficiency of air delivery, the connection between the second air passage 114 and the fifth air passage 214 can be sealed by using a sealing ring, gasket, or other materials in conjunction with compression.

[0113] In some embodiments, the sand-spraying air inlet 212 is connected to an air source via a pipeline and a solenoid valve; wherein, the air source can be a high-pressure gas cylinder or an air compressor; in addition, the solenoid valve is connected to a controller to achieve automatic opening and closing.

[0114] In some embodiments, the compensating air constriction plug 212a is disposed at the sand-spreading air inlet 212. The end of the compensating air constriction plug 212a with a smaller inner diameter is connected to the sand-spreading air inlet 212, and the end with a larger inner diameter is connected to the fifth air passage 214, so as to limit the flow and distribute the flow rate.

[0115] In the above embodiments, this application provides a second air passage 114 on the valve body 110 that is connected to the sand inlet 115, and a fifth air passage 214 on the sand spreading body 210, one end of which is connected to the sand spreading air inlet 212 via a compensating air constriction plug 212a and the other end of which is connected to the second air passage 114. The second air passage 114 and the fifth air passage 214 form a compensating air passage. The compensating air can disturb the sand particles 500 near the sand inlet 115 through this air passage, assisting the sand particles 500 to smoothly enter the inner cavity and the impeller shaft cavity 211, thereby improving the smoothness of the sand particle 500 conveying.

[0116] In some embodiments, such as Figure 7 As shown, the impeller shaft 240 includes a plurality of impellers 241, which are evenly distributed around the circumference to achieve the purpose of driving the impeller shaft 240 to transport sand via the drive member 250.

[0117] Preferably, the number of impellers 241 is 10.

[0118] In some embodiments, the outer diameter of the impeller 241 is slightly smaller than the inner diameter of the reinforcing sleeve 211a, forming a preset gap between them. Since the sand used in train sand-spreading devices is generally limited only to a maximum diameter, not a minimum diameter, if this gap is smaller than the maximum diameter of the sand, even if the gap is extremely small, there is still a risk that sand will enter between the impeller shaft 240 teeth and the sleeve, potentially causing the impeller shaft 240 to jam. Therefore, this application designs the gap to be larger than the maximum diameter of the sand, structurally preventing sand from entering the mating gap and causing jamming. Under this design, although some sand will fall through this gap, at a specific rotational speed of the impeller shaft 240, the amount of sand falling remains stable and does not affect the control of the main amount of sand through the rotation of the impeller shaft 240, thus still achieving the dynamic adjustment function of the sand-spreading amount.

[0119] In some embodiments, a sand flow channel 242 is provided on the impeller shaft 240, which is used to allow sand particles 500 to pass through when the impeller shaft 240 stops rotating.

[0120] In some embodiments, the sand flow channel 242 is arranged circumferentially through the root of the impeller 241 along the impeller shaft 240, that is, the sand flow channel 242 is annular; so as to achieve the purpose of sand flowing out from the sand flow channel 242 when the impeller shaft 240 is stationary, and most of the sand being pushed away by the impeller 241 when the impeller shaft 240 rotates at a certain speed.

[0121] In some embodiments, the sand flow channel 242 is a plurality of through holes arranged radially along the impeller shaft 240.

[0122] In the above embodiments, this application provides a sand flow channel 242 (i.e., a safe mode sand flow port) on the impeller shaft 240. When the impeller shaft 240 stops rotating, sand particles 500 can flow through the sand flow channel 242 to meet the basic sand spreading requirements under conditions such as motor failure and impeller shaft 240 being unable to rotate, ensuring that the device can still play a certain sand spreading role under special circumstances; and to realize the quantitative sand spreading function through the sand flow channel 242 under the action of sand inlet air and sand blowing air when the drive component 250 fails, thereby improving operational reliability.

[0123] In some embodiments, a sand blowing seat 260 is provided on the side of the sand spreading body 210 away from the mechanical locking mechanism 100. The sand blowing seat 260 is provided with a sand discharge channel 262 through the sand particles 500 in the outflow direction. The sand discharge channel 262 is connected to the impeller shaft cavity 211.

[0124] In some embodiments, the sand blowing seat 260 is installed on the side of the sand spreading body 210 away from the mechanical locking mechanism 100 by screws, and the sand blowing seat 260 is sealed to the sand spreading body 210 by a seventh sealing ring 261.

[0125] In some embodiments, the seventh sealing ring 261 is an O-ring.

[0126] In the above embodiments, this application provides a sand blowing seat 260 on the side of the sand spreading body 210 away from the mechanical locking mechanism 100, and provides a sand discharge channel 262 communicating with the impeller shaft cavity 211 through the sand blowing seat 260 along the flow direction of the sand particles 500, providing a discharge path for the sand particles 500 transported downstream by the impeller shaft 240, controlling the final sand discharge direction, so that the sand particles 500 can flow stably to the wheel-rail contact area, and ensuring the sand spreading effect.

[0127] In some embodiments, such as Figure 5As shown, the sand blowing base 260 is provided with a sand blowing air passage 263 and a sand blowing air inlet 263a. The sand blowing air passage 263 is connected to the sand blowing air inlet 263a through a sand blowing air constriction plug 163c, and the sand blowing air passage 263 is connected to the sand discharge channel 262 through a sand blowing air duct 263b. The end of the sand blowing air constriction plug 163c with a smaller inner diameter is connected to the sand blowing air inlet 263a, and the end with a larger inner diameter is connected to the sand blowing air passage 263, so that the flow rate can be adjusted by replacing the sand blowing air constriction plug 163c.

[0128] In some embodiments, the sand blowing air passage 263 is a ring structure and is arranged along the circumference of the sand blowing seat 260.

[0129] In some embodiments, the sandblasting air inlet 263a is connected to an air source via a pipeline and a solenoid valve; wherein the air source can be a high-pressure gas cylinder or an air compressor; in addition, the solenoid valve is connected to a controller to achieve automatic opening and closing.

[0130] In some embodiments, there is at least one sand blowing duct 263b, and each sand blowing duct 263b is arranged at circumferential intervals along the sand discharge channel 262.

[0131] Preferably, the number of sand blowing ducts 263b is 4.

[0132] In some embodiments, the sand blowing duct 263b is arranged obliquely downward to achieve downward sand blowing. Specifically, the axis of the sand blowing duct 263b forms an acute angle with the plane perpendicular to the axis of the sand discharge channel 262, and the projection of the direction vector along the axis of the sand blowing duct 263b from the end connected to the sand blowing air passage 263 towards the interior of the sand discharge channel 262 in the direction of sand particle 500 outflow is the same as the direction of sand particle 500 outflow.

[0133] In some embodiments, the angle between the axis of the sand blowing duct 263b and the plane perpendicular to the axis of the sand discharge channel 262 is 15°. If the angle is less than 15°, the inclination of the sand blowing duct 263b is too small, and its axis is closer to the vertical plane of the axis of the sand discharge channel 262. In this case, after the sand blowing air is ejected from the duct, the airflow direction deviates little from the main direction of the sand particles 500 flowing downward along the sand discharge channel 262. The boosting force of the airflow on the sand particles 500 is mainly dispersed in the horizontal direction, which is difficult to effectively superimpose on the downward movement trend of the sand particles 500. As a result, the downward acceleration effect obtained by the sand particles 500 is weakened, the sandblasting speed is slowed down, and the requirement for rapid sandblasting cannot be met.

[0134] In some embodiments, the angle between the axis of the sand blowing duct 263b and the plane perpendicular to the axis of the sand discharge channel 262 is 60°. If the angle is greater than 60°, the inclination of the sand blowing duct 263b is too large, and its axis is closer to the direction of sand particle 500 flow out along the sand discharge channel 262. In this case, although the sand blowing air can generate a strong downward thrust on the sand particles 500 after being ejected, the excessively inclined airflow may form an airflow vortex at the outlet of the sand discharge channel 262, resulting in a smaller distribution range of the ejected sand particles 500, which cannot uniformly cover the wheel-rail contact area, thus reducing the effect of sand spreading and adhesion, and even affecting the normal wheel-rail contact due to the local accumulation of sand particles 500.

[0135] In some embodiments, the angle between the axis of the sand blowing duct 263b and the plane perpendicular to the axis of the sand discharge channel 262 is 15° to 60°, so as to achieve the purpose of rapid sandblasting.

[0136] Preferably, the angle between the axis of the sand blowing duct 263b and the plane perpendicular to the axis of the sand discharge channel 262 is 45°.

[0137] In the above embodiments, this application provides a sand blowing air passage 263 and a sand blowing air inlet 263a on the sand blowing seat 260. The sand blowing air passage 263 is connected to the sand blowing air inlet 263a through the sand blowing air constriction 163c, and is connected to the sand discharge channel 262 through the sand blowing air duct 263b. The sand blowing air can enter the sand discharge channel 262 through the air passage, pushing the sand particles 500 to be sprayed out quickly. At the same time, the sand blowing can be delayed after the sand spreading is completed to clean the residual sand particles 500 in the sand discharge channel 262 and avoid the channel blockage.

[0138] The principle of this application is as follows: like Figure 5 As shown, when sand is not being spread, neither the sand spreading air inlet 212 nor the sand blowing air inlet 263a is connected to the air source, and the motor speed is 0. At this time, the spring 130 pushes the piston 150, which in turn drives the valve stem 140 to move downward. The valve core sealing ring 142a at the end 142 is tightly fitted with the side of the impeller shaft cavity 211 facing the mechanical locking structure to achieve a sealing function, which can effectively isolate the sand box 400 from the atmosphere. Therefore, the sand spreading unit does not require drying air or heating rods.

[0139] like Figure 6As shown, during sand spreading, both the sand spreading air inlet 212 and the sand blowing air inlet 263a are connected to the air source. The sand spreading air enters the sand spreading air inlet 212 of the sand spreading body 210, and then enters the sand inlet air path and the compensation air path respectively. The sand inlet air enters the piston air chamber 116 of the valve body 110. The sand inlet air pressure in the air chamber overcomes the force of the spring 130 and pushes the piston 150 upward quickly. The piston 150 drives the valve stem 140 to move upward. At this time, the sand inlet 115 is fully opened. At the same time, the sand inlet air passes from the piston air chamber 116 into the third air path 141 of the valve stem 140, and then sprays the sand inlet air downward through the valve stem constriction plug 142b to achieve sand blowing. Among them, by replacing the compensation air constriction plug 212a and the valve stem constriction plug 142b of different models (i.e., different inner diameters), the flow distribution of the two air paths can be adjusted.

[0140] At this time, the sand near the sand inlet 115 of the compensating wind disturbance valve body 110, along with the sand inlet air, is accelerated to flow into the sand spreading actuator 200. The sand enters the impeller shaft cavity 211 in the sand spreading actuator 200. The motor speed is controlled to drive the impeller shaft 240 to rotate. The impeller 241 of the impeller shaft 240 transports the sand in the impeller shaft cavity 211 from the upper part to the lower part of the cavity, and then the sand enters the sand discharge channel 262 inlet of the sand blowing seat 260. The sand blowing air enters the sand blowing air passage 263 of the sand blowing seat 260, and is guided into the sand discharge channel 262 through four downward-angled 45° sand blowing air ducts 263b, thereby driving the sand flowing into the sand blowing seat 260 to achieve rapid sand spraying. Among them, the motor speed can be adjusted according to the sand spreading amount command from the upstream of the train to achieve continuous dynamic adjustment of the sand spreading amount, effectively improving the sand utilization rate.

[0141] When the motor malfunctions, the impeller shaft 240 remains stationary, thus the impeller 241 ceases its sand-carrying function. At this time, all sand flows into the sand-flowing channel 242 of the impeller shaft 240. The sand is then propelled from the sand-flowing channel 242 at the center of the impeller shaft 240 into the sand-blowing seat 260 by the sand-inlet air, achieving quantitative sand distribution. In normal mode, when the impeller shaft 240 rotates above a certain speed, most of the sand is displaced by the impeller 241, resulting in a very small amount of sand flowing into the sand-flowing channel 242, which does not affect the continuous dynamic adjustment of the sand-distribution function. The quantitative sand-distribution function in safety mode is achieved through the sand-flowing channel 242 at the center of the impeller shaft 240.

[0142] When the sand spreading ends, the sand spreading air is turned off, cutting off the connection between the sand spreading air inlet 212 and the air source. The spring 130 automatically locks the air. At this time, the sand blowing air is delayed in closing to ensure that there is no sand residue in the sand spreading pipe after one sand spreading, thus achieving the sand cleaning function.

[0143] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A sand-spreading device, characterized in that, It includes a mechanical locking mechanism (100) and a sand-spreading actuator (200) connected to the mechanical locking mechanism (100); wherein the mechanical locking mechanism (100) includes: Valve body (110), the valve body (110) is provided with an inner cavity and a sand inlet (115) communicating with the inner cavity. A spring (130) is disposed in the inner cavity and on the side away from the sand-spreading actuator (200); A piston (150) is slidably and sealed in the inner cavity and reciprocates along the axis of the inner cavity. The piston (150) is located on the side of the spring (130) near the sand-spraying actuator (200) and is connected to the spring (130). The portion of the inner cavity located on the side of the piston (150) facing the spring (130) is a spring air chamber (117). End cap (160), the end cap (160) is sealed and fixed in the inner cavity and is disposed between the sand inlet (115) and the piston (150). The part of the inner cavity located between the end cap (160) and the piston (150) is the piston air chamber (116). The end cap (160) is provided with a through hole. A valve stem (140) is connected to the piston (150). The valve stem (140) is slidably sealed through the through hole. The valve stem (140) has an end head (142) near the sand-spreading actuator (200). A valve stem plug (142b) is provided on the side of the end head (142) near the sand-spreading actuator (200). The valve stem plug (142b) is connected to the piston air chamber (116). The sand-spreading actuator (200) includes: Impeller shaft cavity (211), the impeller shaft cavity (211) is connected to the sand inlet (115); Impeller shaft (240), which is rotatably disposed within the impeller shaft cavity (211); When the air pressure in the piston chamber (116) is less than the sum of the air pressure in the spring chamber (117) and the thrust of the spring (130), the thrust of the spring (130) acts on the piston (150), thereby pushing the end (142) to seal against the side of the impeller shaft cavity (211) near the mechanical locking mechanism (100); when the air pressure in the piston chamber (116) is greater than the sum of the air pressure in the spring chamber (117) and the thrust of the spring (130), The piston (150) moves away from the sand-spreading actuator (200), causing the end (142) to separate from the impeller shaft cavity (211); sand particles (500) enter the inner cavity from the sand inlet (115), and some of the compressed air in the piston air chamber (116) is ejected from the valve stem constriction (142b), pushing the sand particles (500) into the impeller shaft cavity (211), and the impeller shaft (240) transports the sand particles (500) in the direction of sand particle (500) outflow.

2. The sand spreading device according to claim 1, characterized in that, The inner cavity extends along the axis of the valve body (110), and an adjusting member (120) is provided on the side of the inner cavity away from the sand-spreading actuator (200). A cover plate (111) is sealed on the end of the valve body (110) away from the sand-spreading actuator (200). The adjusting member (120) abuts against the side of the spring (130) away from the piston (150), and the adjusting member (120) can reciprocate along the axis of the inner cavity.

3. A sand-spreading device according to claim 2, characterized in that, The sand-spreading actuator (200) includes a sand-spreading body (210), which is sealed to the valve body (110). The sand-spreading body (210) is located downstream of the valve body (110) in the direction of sand (500) outflow. The impeller shaft cavity (211) is disposed inside the sand-spreading body (210) and is disposed through the sand (500) in the direction of sand (500) outflow. The impeller shaft cavity (211) is connected to the inner cavity.

4. A sand-spreading device according to claim 3, characterized in that, A reinforcing sleeve (211a) is provided on the inner wall of the impeller shaft cavity (211), and the reinforcing sleeve (211a) is used to prevent sand particles from scratching the inner wall of the impeller shaft cavity (211).

5. A sand-spreading device according to claim 4, characterized in that, The impeller shaft cavity (211) is provided with a first sealing bearing (223) and a second sealing bearing (232) on both sides. The first sealing bearing (223) and the second sealing bearing (232) are coaxial and their axes are perpendicular to the outflow direction of the sand particles (500). The two sides of the impeller shaft (240) are respectively connected to the first sealing bearing (223) and the second sealing bearing (232). The sand-spreading body (210) is provided with a first bearing seat (220) and a second bearing seat (230), the first sealed bearing (223) is disposed in the first bearing seat (220), and the second sealed bearing (232) is disposed in the second bearing seat (230); The impeller shaft (240) is rotatably sealed through the first bearing housing (220) at one end near the first sealed bearing (223) and connected to the output shaft of the drive (250).

6. A sand-spreading device according to any one of claims 3 to 5, characterized in that, The valve body (110) is provided with a first air passage (113), which is connected to the piston air chamber (116); the valve stem (140) is provided with a third air passage (141), which is used to connect the piston air chamber (116) and the valve stem plug (142b). The sand-spreading body (210) includes a sand-spreading air inlet (212) and a fourth air passage (213), the fourth air passage (213) being used to connect the sand-spreading air inlet (212) and the first air passage (113).

7. A sand-spreading device according to claim 6, characterized in that, The valve body (110) is provided with a second air passage (114), which is connected to the sand inlet (115); The sand-spreading body (210) is provided with a fifth air passage (214). One end of the fifth air passage (214) is connected to the sand-spreading air inlet (212) through a compensating air constriction plug (212a), and the other end of the fifth air passage (214) is connected to the second air passage (114).

8. A sand-spreading device according to any one of claims 1 to 5, characterized in that, A sand flow channel (242) is provided on the impeller shaft (240), which is used to allow sand particles (500) to pass through when the impeller shaft (240) stops rotating.

9. A sand-spreading device according to any one of claims 3 to 5, characterized in that, A sand blowing seat (260) is provided on the side of the sand spreading body (210) away from the mechanical locking mechanism (100). The sand blowing seat (260) is provided with a sand discharge channel (262) through the sand particles (500) outflow direction. The sand discharge channel (262) is connected to the impeller shaft cavity (211).

10. A sand-spreading device according to claim 9, characterized in that, The sand blowing seat (260) is provided with a sand blowing air passage (263) and a sand blowing air inlet (263a). The sand blowing air passage (263) is connected to the sand blowing air inlet (263a) through a sand blowing air blockage (163c). The sand blowing air passage (263) is connected to the sand discharge channel (262) through a sand blowing air duct (263b).

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