Sand box sand level detection device and method for railway vehicle

Abstract

The invention discloses a sand position detection device and method for a rail vehicle sand box, and relates to the technical field of rail transportation equipment. The detection device comprises a cylinder, a piston, a spring, a laser ranging sensor, a data processor and a display module. In the detection method, a corresponding relationship table between a piston height node and a remaining sand amount node in a sand box is constructed, and the piston height is detected by a laser ranging sensor. The data processor can find the remaining sand amount node in the sand box corresponding to the piston height in the corresponding relationship table according to the piston height detected by the laser ranging sensor, and display the remaining sand amount node in the sand box on the display module, so that a driver in a cab can obtain information on the remaining sand amount in the sand box in time; the introduction of the corresponding relationship table can greatly simplify the programming process, and the reliability is extremely high; the invention can be applicable to sand position detection of different sand box structures.

Description

Technical Field

[0001] The present invention relates to the technical field of rail transit equipment, and in particular to a device and method for detecting sand position in a sand box of a rail vehicle. Background Art

[0002] Due to the complex operating environment and high speed of EMUs, when encountering bad weather such as rain and snow, the rails will be very slippery, and there is a risk of idling during traction or sliding during braking. In order to improve the adhesion between the wheels and the rail surface, EMUs are generally equipped with sand spreading devices. The sand spreading device consists of a sand box and a sand discharge unit, and the driver or the train braking system controls the sand discharge amount of the sand spreading device. In order to ensure safe operation, there must be enough sand in the sand box, so it is necessary to add sand to the sand box in a timely manner. Since the sand box is generally placed at the bottom of the car body, the operator cannot directly observe or detect the height of the sand surface in the sand box due to the limitation of the installation position of the sand box, which in turn affects the driver's judgment on adjusting the sand flow and the amount of sand injection.

[0003] The Chinese patent No. 201310461922.8 discloses a device for detecting the position of the sand volume in the sand box of a rail transit vehicle. The device is to set a pressure sensor at the bottom of the sand box to detect the weight of the sand box in real time, so as to judge the amount of sand according to the weight of the sand box, and then control the time and amount of sand addition. Since the sand box has various forms and the sand box is not a regular container, it is complicated and not conducive to the unification of specifications to write different programs for sand boxes of different shapes and different shapes of each part of the sand box; when the vehicle is driving on a long slope or curve, the sand and gravel will be affected by centrifugal force, increasing or decreasing the force acting on the sensor, so that the amount of sand cannot be correctly measured, and it is not suitable for use on rail vehicles that have been put into operation.

[0004] A Chinese patent with patent number 201720359609.7 discloses a device for detecting the position of the amount of sand in a sand box of a rail transit vehicle. The device is to set small balls of different materials inside and outside the sand box, and connect them with a rope with a scale. It has defects: on the one hand, when using this device, the driver needs to get off the vehicle to observe if he wants to know the amount of sand; on the other hand, the fluidity of the sand and gravel in the sand box must be ensured during the driving process of the vehicle, so water, oil and other substances must be prevented from entering the sand box. Since the rope is a movable part that goes back and forth in and out of the sand box, the sealing cannot be guaranteed, so that there will be a risk of idling during traction or sliding during braking due to the lack of sand blasting; furthermore, the shaking of the vehicle during the forming process and the fluidity of the sand and gravel may bury the small balls, making it impossible to correctly measure the amount of sand in the sand box. Summary of the invention

[0005] The present invention provides a device and method for detecting the sand level of a sand box of a rail vehicle, which can alleviate the above-mentioned problem.

[0006] In order to alleviate the above-mentioned problems, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides a sand level detection device for a sand box of a railway vehicle, comprising:

[0008] A cylinder, with an open upper end and a closed lower end, is vertically installed in a sand box, and the interior is divided into a sand-flowing section and a piston motion section located below the sand-flowing section by a piston baffle, the piston baffle is a non-solid plate that can pass sand, the cylindrical side wall of the sand-flowing section is a mesh wall that can pass sand, the cylindrical side wall of the piston motion section is a solid wall that cannot pass sand, and the baffle is at the same height as the top of the sand-flowing tube in the sand box;

[0009] A piston, which is slidably sleeved on the piston motion section;

[0010] A spring, which is a compression spring vertically mounted on the piston moving section, with its upper end abutting against the piston and its lower end abutting against the bottom surface in the cylinder;

[0011] A laser distance measuring sensor is installed below the cylinder, with its laser emitting end pointing vertically upward and extending into the cylinder to face the piston, and is used to collect piston height data, where the piston height refers to the distance between the piston and the laser distance measuring sensor;

[0012] A data processor is connected to the laser ranging sensor through a data transmission module, and is used to receive the piston height data, process the piston height data, and output the remaining sand amount data in the sand box;

[0013] The display module is installed in the rail vehicle cab and is electrically connected to the data processor to display the data of the amount of remaining sand in the sand box.

[0014] The technical effect of the technical scheme is that the pressure on the spring can be the sum of the weight of the piston, the friction between the piston and the inner wall of the piston moving section, and the weight of the sand and gravel. When the sand box is full of sand, the weight of the sand and gravel is the largest, and the spring is compressed to the maximum. When all the sand and gravel are discharged, the weight of the sand and gravel is the smallest, and the spring is compressed to the minimum. As the weight of the sand and gravel decreases, the spring compression amplitude decreases. Based on this, the detection of the piston height by the laser ranging sensor can reflect the remaining sand amount in the sand box, and then realize the detection of the sand position in the sand box. The overall structure of the detection device is simple, and the detection accuracy is extremely high. It will not affect the sand spreading process of the sand box. The data processor can output the corresponding data of the detection result to the display module for display, and the driver in the cab can know the remaining sand amount in the sand box without getting off the vehicle.

[0015] Optionally, the piston baffle is composed of a plurality of unit plates fixedly connected to the cylinder, and the unit plates are arranged in sequence at equal intervals around the annular inner wall of the cylinder.

[0016] The technical effect of the technical solution is that a sand-passing gap is left between the unit plates, so that the piston baffle can pass the sand and can also block the piston to prevent the piston from entering the sand-flowing section of the cylinder.

[0017] In a second aspect, the present invention provides a method for detecting the sand position of a sand box of a railway vehicle, which adopts the above-mentioned sand position detection device of a sand box of a railway vehicle, and specifically comprises the following steps:

[0018] S1, constructing a correspondence table between piston height nodes and remaining sand amount nodes in the sand box, and writing the correspondence table into the data processor in a program manner, wherein the correspondence table records a number of piston height nodes and a number of remaining sand amount nodes in the sand box, and the piston height nodes correspond to the remaining sand amount nodes in the sand box one by one, and the smaller the piston height node is, the larger the corresponding remaining sand amount node in the sand box is;

[0019] S2, using a laser range sensor to measure the real-time piston height data, and transmitting the real-time piston height data to a data processor through a data transmission module;

[0020] S3. Whenever the real-time piston height reaches a piston height node, the data processor outputs the node data of the remaining sand amount in the sand box corresponding to the piston height node and displays it on the display module. If the real-time piston height does not reach its next piston height node, the display module displays the previous piston height node.

[0021] The technical effect of the technical solution is: it can easily realize the detection of the sand position of the sand box of the rail vehicle, and the data processor can find the node of the remaining sand amount in the sand box corresponding to the piston height in the correspondence table according to the piston height detected by the laser ranging sensor, and display the node of the remaining sand amount in the sand box on the display module, so that the driver in the cab can obtain the information of the remaining sand amount in the sand box in time; the introduction of the correspondence table can greatly simplify the programming process, and the reliability is extremely high; this method can be applied to the detection of the sand position in the sand box when different sand box structures are used.

[0022] Optionally, the data processor is electrically connected to an alarm device, wherein a node of the remaining sand amount in the sand box is an alarm sand amount point, and when the alarm sand amount point is displayed on the display module, the alarm device alarms.

[0023] The technical effect of this technical solution is: if the driver fails to see the remaining sand amount displayed on the display module in time due to habit problems, the alarm device can alarm at the sand amount alarm point to better avoid the situation where there is no sand to be spread in the sand box.

[0024] Optionally, in step S1, the method for determining the correspondence table includes the following steps:

[0025] S11, repeating a times of sand spreading experiment, the sand spreading experiment comprising:

[0026] Add sand to the sand box until it is full, and discharge all the sand in the sand box at a uniform speed through the sand spreading unit. At the start of sand discharge, use a laser distance sensor to measure the piston height once, and then use a laser distance sensor to measure the piston height once every interval t. Let n be the total number of piston height measurements in a sand spreading experiment, and take n>3. Its size is determined according to the full sand volume in the sand box. Its value can ensure that in each sand spreading experiment, when the n-1th piston height measurement is performed, the sand and gravel are not fully discharged, and when the nth piston height measurement is performed, the sand and gravel are completely discharged;

[0027] The speed of the uniform outflow of sand and gravel and the total number of piston height measurements were equal in each sand spreading experiment;

[0028] S12, taking an average value of the piston heights measured in the same order of each sand spreading experiment, and using the average values ​​of each piston height as each piston height node in the corresponding relationship table;

[0029] S13, let t Ni represents the i-th interval time t in the N-th sand spreading experiment, N = 1, 2, ..., a; through the formula and Calculate the sand and gravel flow rate b, where T is the average time required from full sand to all sand and gravel flowing out of the sand box, and V represents the maximum sand and gravel capacity of the sand box;

[0030] S14, through the formula W j = tjb Calculate the amount of sand and gravel that has flowed out each time the piston height is measured W j , where j represents the order of piston height measurement in the sand spreading experiment, j = 0, 1, 2, ..., n;

[0031] S15, through the formula Calculate the remaining sand amount node C in each sand box in the corresponding relationship table j , the corresponding relationship table is determined according to the remaining sand amount nodes in each sand box and the piston height nodes.

[0032] The technical effect of the technical solution is that the corresponding relationship table determined by the method can ensure with high accuracy that when the piston height reaches a certain piston height node, the actual amount of remaining sand in the sand box is displayed on the display module.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the embodiments of the present invention are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 Schematic diagram of the installation structure of the sand box sand position detection device for a rail vehicle in the sand box according to the embodiment;

[0036] Figure 2 1 is a schematic diagram of the installation structure of the sand box sand level detection device for the rail vehicle in the embodiment. In order to show the local structural relationship, it is relative to Figure 1 The sand box and sand outlet pipe are not drawn;

[0037] Figure 3 1 is a schematic top view of the installation structure of the sand box sand level detection device for a rail vehicle in the embodiment, wherein the sand box is not shown;

[0038] Figure 4 is a schematic block diagram of the structure of the sand box sand level detection device for a rail vehicle described in an embodiment;

[0039] In the figure: 1-cylinder, 2-sand isolation plate, 3-sand flow pipe, 4-exhaust pipe, 5-piston, 6-piston baffle, 7-sand spreading unit, 8-laser ranging sensor, 9-sand box, 10-sand outlet pipe, 11-spring. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In the description of the present invention, it should be noted that the terms "upper", "lower", "vertical", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0043] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting", "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] Example 1

[0045] Please refer to Figure 1 to Figure 4 This embodiment provides a sand level detection device for a rail vehicle sand box 9, comprising:

[0046] The cylinder 1 is open at the upper end and closed at the lower end, and is vertically installed in the sand box 9. The interior is divided into a quicksand section and a piston 5 moving section located below the quicksand section by a piston baffle 6. The piston baffle 6 is a non-solid plate that can pass sand. The side wall of the cylinder 1 in the quicksand section is a mesh wall that can pass sand. The side wall of the cylinder 1 in the piston 5 moving section is a solid wall that cannot pass sand. The baffle is at the same height as the top of the quicksand pipe 3 in the sand box 9.

[0047] The piston 5 is slidably sleeved on the piston 5 moving section;

[0048] Spring 11, which is a compression spring vertically mounted on the moving section of piston 5, with its upper end abutting against piston 5 and its lower end abutting against the bottom surface inside cylinder 1;

[0049] The laser distance measuring sensor 8 is installed below the cylinder 1, with its laser emitting end pointing vertically upward and extending into the cylinder 1 to face the piston 5, and is used to collect piston height data. The piston height refers to the distance between the piston 5 and the laser distance measuring sensor 8;

[0050] A data processor, which is connected to the laser distance sensor 8 through a data transmission module, is used to receive the piston height data, process the piston height data, and output the remaining sand amount data in the sand box;

[0051] The display module is installed in the rail vehicle cab and is electrically connected to the data processor to display the data of the remaining sand amount in the sand box.

[0052] In this embodiment, the structural size of the spring 11, the piston 5 and the cylinder 1 can be determined according to the volume of the sand box full of sand and gravel, ensuring that when the sand and gravel are completely discharged, the piston 5 is pushed upward by the spring 11 and moves to a position close to the piston baffle 6. When the sand and gravel are in a full sand state, the spring 11 is affected by the weight of the sand and gravel and has a significantly larger compression amount.

[0053] In this embodiment, the piston 5 and the inner wall of the moving section of the piston 5 are always sealed, which is the basis of the movement of the piston 5 and ensures that sand and gravel will not be squeezed between the inner wall of the cylinder 1 and the outer wall of the piston 5.

[0054] In this embodiment, the data processor is a programmable processor, and the display module is an LCD display.

[0055] In this embodiment, as a structural selection method, the piston baffle 6 is composed of a plurality of unit plates fixedly connected to the cylinder 1. The unit plates are arranged in sequence at equal intervals around the annular inner wall of the cylinder 1. A sufficiently large spacing area must be reserved between the unit plates for sand and gravel to pass through, ensuring that the sand and gravel in the cylinder 1 can flow from the side wall mesh of the quicksand section and the top opening of the cylinder 1 to the outside of the cylinder 1, or the sand and gravel can flow into the cylinder 1 in the reverse direction.

[0056] In this embodiment, the sand box, the sand outlet pipe 10, the sand flow pipe 3, the exhaust pipe 4, the sand isolation plate 2, and the sand spreading unit 7 are all prior arts, and their specific structures and relative connection relationships are not further described here.

[0057] Example 2

[0058] Please refer to Figure 1 to Figure 4 This embodiment provides a method for detecting the sand level of a sand box of a rail vehicle, which adopts the above-mentioned sand box sand level detection device of a rail vehicle, and specifically includes the following steps:

[0059] S1, construct a correspondence table between piston height nodes and remaining sand amount nodes in the sand box, and write the correspondence table into a data processor in the form of a program, wherein the correspondence table records a number of piston height nodes and a number of remaining sand amount nodes in the sand box, and the piston height nodes correspond to the remaining sand amount nodes in the sand box one by one. The smaller the piston height node is, the larger the corresponding remaining sand amount node in the sand box is;

[0060] S2, using the laser range sensor 8 to measure the real-time piston height data, and transmitting the real-time piston height data to the data processor through the data transmission module;

[0061] S3. Whenever the real-time piston height reaches a piston height node, the data processor outputs the node data of the remaining sand amount in the sand box corresponding to the piston height node and displays it on the display module. If the real-time piston height does not reach its next piston height node, the display module displays the previous piston height node.

[0062] In this embodiment, the data processor can find the node of the remaining sand amount in the sand box corresponding to the piston height in the correspondence table according to the piston height detected by the laser ranging sensor 8, and display the node of the remaining sand amount in the sand box on the display module, so that the driver in the cab can obtain the information of the remaining sand amount in the sand box in time.

[0063] In this embodiment, during the sand discharge process, the pressure on the spring 11 is mainly the sum of the weight of the piston 5, the friction between the piston 5 and the inner wall of the piston 5 moving section, and the weight of the sand and gravel. When the sand box is full of sand, the sand surface is not over the sand flowing tube 3, and the space above the piston 5 in the cylinder 1 is also full. At this time, the piston 5 is at the lowest position. As the amount of sand in the sand box decreases, the sand surface in the sand box decreases as a whole. At this time, since the upper half of the cylinder 1 is a mesh structure, the amount of sand in the mesh cylinder 1 will also decrease, and the sand and gravel pressure on the indirect spring 11 will decrease, thereby pushing the piston 5 to move upward, so that the piston height changes. When the amount of sand in the sand box is equal to the sand flowing tube 3, that is, the position height of the piston baffle 6 in the cylinder 1, the piston 5 rises to the highest position, and the sand in the sand box cannot flow out of the sand flowing tube 3.

[0064] As an option of this embodiment, the data processor is electrically connected to an alarm device, wherein a node of the remaining sand amount in a sand box is an alarm sand amount point, and when the alarm sand amount point is displayed on the display module, the alarm device alarms.

[0065] Example 3

[0066] Please refer to Figure 1 to Figure 4 With respect to the correspondence table in step S1 of embodiment 2, this embodiment provides a method for determining the correspondence table, comprising the following steps:

[0067] S11. In this embodiment, in order to facilitate listing of complete examples, a=5 is taken, that is, the sand-sprinkling experiment is repeated 5 times. The sand-sprinkling experiment includes:

[0068] Add sand to the sand box until it is full, and discharge all the sand in the sand box at a uniform speed through the sand spreading unit. At the start of sand discharge, the laser distance sensor 8 is used to measure the piston height once, and then the laser distance sensor 8 is used to measure the piston height once every interval t. Let n be the total number of piston height measurements in a sand spreading experiment, and n>3. Its size is determined according to the full sand volume in the sand box. Its value can ensure that in each sand spreading experiment, when the n-1th piston height measurement is performed, the sand and gravel are not completely discharged, and when the nth piston height measurement is performed, the sand and gravel are completely discharged;

[0069] The speed at which sand and gravel flow out uniformly and the total number of piston height measurements are equal in each sand spreading experiment.

[0070] In this embodiment, the total time required for each sand spreading experiment may be different, so the total number of piston height measurements may also be different. The following explanation is made: During the measurement process, since the speed of the sand and gravel flowing out at a uniform speed is the same each time, theoretically, the number of times the piston position is measured and recorded each time is the same. However, due to various factors (such as different sand and gravel specifications caused by artificial reasons when adding sand and gravel to the sand box, and the sand outlet is damp and causes sand to be blocked), the total number of piston height measurements in a sand spreading experiment may be different from that in other sand spreading experiments. However, since the speed of the sand and gravel flowing out at a uniform speed is the same each time during the measurement process, even if the total number of piston height measurements in a sand spreading experiment is different, it is only a very small probability event. In the actual experiment, even high-pressure sand spreading (i.e., high-flow sand spreading) has not occurred in a=5 sand spreading experiments. This low-probability event is located as an impossible event during this experiment. In the actual operation process, once this event occurs, all data in the sand spreading experiment will be deleted, that is, the value of a is always the number of sand spreading experiments with the same total number of piston height measurements.

[0071] In this embodiment, the interval time t is 3s.

[0072] In this embodiment, in order to facilitate a complete listing of examples, n=5 is taken. However, in fact, the larger n is, the more accurate the experiment is. In the last 3s of a sand spreading experiment, the sand and gravel in the sand box may have flowed out and the timing is still on. This will cause the sand and gravel flow rate b to become smaller, that is, there is an error. In actual circumstances, n is much larger than 5, that is, the last 3s accounts for a very small part of the time required for a single sand spreading experiment process, so the error is within the allowable error range.

[0073] S12, taking the average of the piston heights measured in the same order of each sand spreading experiment, and using the average of each piston height as each piston height node in the corresponding relationship table, as follows:

[0074] 1) Establish an array of recording time and piston height for each sand spreading experiment.

[0075] Let S Nj is the piston height measured in the sand-spreading experiment, j represents the piston height measurement sequence in the sand-spreading experiment, j = 0, 1, 2, 3, 4; N is the sand-spreading experiment sequence, N = 1, 2, 3, 4, 5; let t Ni represents the i-th 3s interval time in the N-th sand-spreading experiment, i=1, 2, 3, 4; in each sand-spreading experiment, the arrays of recording time and piston height are shown in corresponding Tables 1 to 5;

[0076] Table 1

[0077] time Piston height 0 <![CDATA[S 10 ]]> <![CDATA[t 11 =3s]]> <![CDATA[S 11 ]]> <![CDATA[t 12 =3s]]> <![CDATA[S 12 ]]> <![CDATA[t 13 =3s]]> <![CDATA[S 13 ]]> <![CDATA[t 14 =3s]]> <![CDATA[S 14 ]]>

[0078] Table 2

[0079] time Piston height 0 <![CDATA[S 20 ]]> <![CDATA[t 21 =3s]]> <![CDATA[S 21 ]]> <![CDATA[t 22 =3s]]> <![CDATA[S 22 ]]> <![CDATA[t 23 =3s]]> <![CDATA[S 23 ]]> <![CDATA[t 24 =3s]]> <![CDATA[S 24 ]]>

[0080] Table 3

[0081] time Piston height 0 <![CDATA[S 30 ]]> <![CDATA[t 31 =3s]]> <![CDATA[S 31 ]]> <![CDATA[t 32 =3s]]> <![CDATA[S 32 ]]> <![CDATA[t 33 =3s]]> <![CDATA[S 33 ]]> <![CDATA[t 34 =3s]]> <![CDATA[S 34 ]]>

[0082] Table 4

[0083] time Piston height 0 <![CDATA[S 40 ]]> <![CDATA[t 41 =3s]]> <![CDATA[S 41 ]]> <![CDATA[t 42 =3s]]> <![CDATA[S 42 ]]> <![CDATA[t 43 =3s]]> <![CDATA[S 43 ]]> <![CDATA[t 44 =3s]]> <![CDATA[S 44 ]]>

[0084] Table 5

[0085] time Piston height 0 <![CDATA[S 50 ]]> <![CDATA[t 51 =3s]]> <![CDATA[S 51 ]]> <![CDATA[t 52 =3s]]> <![CDATA[S 52 ]]> <![CDATA[t 53 =3s]]> <![CDATA[S 53 ]]> <![CDATA[t 54 =3s]]> <![CDATA[S 54 ]]>

[0086] 2) Create an array of piston height nodes in the same time interval and corresponding relationship table.

[0087] Theoretically, there should be S 11 =S 21 .........=S 51 ,...............,S 14 =S 24 .........=S 54 However, due to various factors, there are some differences. Therefore, in order to ensure accuracy, the average value of the piston heights measured in the same order of each sand spreading experiment is taken, and the average value of each piston height is used as the piston height node in the corresponding relationship table. j Represents the piston height node, and the array of each piston height node in the same time interval and corresponding relationship table is shown in corresponding table 6.

[0088] Table 6

[0089] Time interval Piston Height Node 0 <![CDATA[E0=(S 10 +S 20 +S 30 +S 40 +S 50 ) / 5]]> <![CDATA[t N1 ]]> <![CDATA[E1=(S 11 +S 21 +S 31 +S 41 +S 51 ) / 5]]> <![CDATA[t N2 ]]> <![CDATA[E2=(S 12 +S 22 +S 32 +S 42 +S 52 ) / 5]]> <![CDATA[t N3 ]]> <![CDATA[E3=(S 13 +S 23 +S 33 +S 43 +S 53 ) / 5]]> <![CDATA[t N3 ]]> <![CDATA[E4=(S 14 +S 24 +S 34 +S 44 +S 54 ) / 5]]>

[0090] S13, through and Calculate the sand and gravel flow rate b, where T is the average time required from full sand to all sand and gravel flowing out of the sand box, and V represents the maximum sand and gravel capacity of the sand box.

[0091] In this embodiment, the sand and gravel flow rate b and the speed at which the sand and gravel flow out at a uniform speed in step S11 are conceptually the same, but the speed at which the sand and gravel flow out at a uniform speed in step S11 is unknown, and it is achieved by controlling the sand spreading unit. The sand and gravel flow rate b here is known after being solved.

[0092] S14, through the formula W j = 3jb Calculate the amount of sand and gravel that has flowed out each time the piston height is measured W j , establish the sand and gravel outflow volume W j Node E with piston height j The corresponding relationship table between them is shown in Table 7;

[0093] Table 7

[0094] <![CDATA[The amount of sand and gravel that has flowed out, W j > <![CDATA[Piston height node E j > <![CDATA[W0=0]]> <![CDATA[E0]]> <![CDATA[W1=3b]]> <![CDATA[E1]]> <![CDATA[W2=6b]]> <![CDATA[E2]]> <![CDATA[W3=9b]]> <![CDATA[E3]]> <![CDATA[W4=12b]]> <![CDATA[E4]]>

[0095] S15, through the formula Calculate the remaining sand amount node C in each sand box in the corresponding relationship table j , according to the remaining sand volume in the sand box node C j and piston height node E j Determine the corresponding relationship table, as shown in Table 8.

[0096] Table 8

[0097]

[0098] In this embodiment, due to the particularity of the sand spreading principle, the sand spreading device HXD1 using air flow pressure difference sand spreading will blow up the sand and gravel during the sand spreading process, causing mutual collision between the sand and gravel, which will change the specifications of the sand and gravel with Mohs hardness mineral grade ≥5, and the sand and gravel used by the vehicle is filled with the standard of less than 0.1mm mass ratio less than 0.5%; less than 0.63mm mass ratio less than 5%; greater than 0.63mm, less than 0.8mm mass ratio less than 30%; greater than 0.8mm, less than 1.6mm mass ratio greater than 50%; greater than 1.6mm, less than 2mm mass ratio less than 30%; greater than 2mm mass ratio less than 5%; greater than 2.5mm mass ratio less than 0.1%. Therefore, the sand and gravel after one measurement may not meet the specifications, that is, in order to ensure the accuracy of the measurement, it is necessary to ensure that the sand and gravel used in the a sand spreading experiment process is of the same specification, and the sand and gravel after measurement cannot be reused.

[0099] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A sand level detection device for a rail vehicle sand box, characterized in that: include: A cylinder, with an open upper end and a closed lower end, is vertically installed in a sand box, and the interior is divided into a sand-flowing section and a piston motion section located below the sand-flowing section by a piston baffle, the piston baffle is a non-solid plate that can pass sand, the cylindrical side wall of the sand-flowing section is a mesh wall that can pass sand, the cylindrical side wall of the piston motion section is a solid wall that cannot pass sand, and the baffle is at the same height as the top of the sand-flowing tube in the sand box; A piston, which is slidably sleeved on the piston motion section; A spring, which is a compression spring vertically mounted on the piston moving section, with its upper end abutting against the piston and its lower end abutting against the bottom surface in the cylinder; A laser distance measuring sensor is installed below the cylinder, with its laser emitting end pointing vertically upward and extending into the cylinder to face the piston, and is used to collect piston height data, where the piston height refers to the distance between the piston and the laser distance measuring sensor; A data processor is connected to the laser ranging sensor through a data transmission module, and is used to receive the piston height data, process the piston height data, and output the remaining sand amount data in the sand box; A display module is installed in the rail vehicle cab and is electrically connected to the data processor to display data on the amount of sand remaining in the sand box; When the sand box is full of sand, the sand surface does not pass the sand flow tube, and the space above the piston in the cylinder is also filled. At this time, the piston is at the lowest position. As the amount of sand in the sand box decreases, the sand surface in the sand box drops as a whole. At this time, since the upper part of the cylinder is a mesh structure, the amount of sand in the mesh cylinder will also decrease. The sand and stone pressure on the indirect spring is reduced, thereby pushing the piston upward, and the piston height changes.

2. The sand level detection device for a rail vehicle sand box according to claim 1, characterized in that: The piston baffle is composed of a plurality of unit plates fixedly connected to the cylinder, and the unit plates are arranged in sequence at equal intervals around the annular inner wall of the cylinder.

3. A method for detecting the sand level of a rail vehicle sand box, characterized in that: The rail vehicle sand box sand level detection device according to claim 1 or 2 is adopted, and specifically comprises the following steps: S1, constructing a correspondence table between piston height nodes and remaining sand amount nodes in the sand box, and writing the correspondence table into the data processor in a program manner, wherein the correspondence table records a number of piston height nodes and a number of remaining sand amount nodes in the sand box, and the piston height nodes correspond to the remaining sand amount nodes in the sand box one by one, and the smaller the piston height node is, the larger the corresponding remaining sand amount node in the sand box is; S2, using a laser range sensor to measure the real-time piston height data, and transmitting the real-time piston height data to a data processor through a data transmission module; S3. Whenever the real-time piston height reaches a piston height node, the data processor outputs the node data of the remaining sand amount in the sand box corresponding to the piston height node and displays it on the display module. If the real-time piston height does not reach its next piston height node, the display module displays the previous piston height node.

4. The method for detecting the sand level of a rail vehicle sand box according to claim 3, characterized in that: The data processor is electrically connected to an alarm device, wherein one of the nodes of the amount of remaining sand in the sand box is an alarm sand amount point, and when the alarm sand amount point is displayed on the display module, the alarm device alarms.

5. The method for detecting the sand level of a sand box of a rail vehicle according to claim 3, characterized in that: In step S1, the method for determining the correspondence table includes the following steps: S11, repeating a times of sand spreading experiment, the sand spreading experiment comprising: Add sand to the sand box until it is full, and discharge all the sand in the sand box at a uniform speed through the sand spreading unit. At the start of sand discharge, use a laser distance sensor to measure the piston height once, and then use a laser distance sensor to measure the piston height once every interval t. Let n be the total number of piston height measurements in a sand spreading experiment, and take n>3. Its size is determined according to the full sand volume in the sand box. Its value can ensure that in each sand spreading experiment, when the n-1th piston height measurement is performed, the sand and gravel are not fully discharged, and when the nth piston height measurement is performed, the sand and gravel are completely discharged; The speed of the uniform outflow of sand and gravel and the total number of piston height measurements were equal in each sand spreading experiment; S12, taking an average value of the piston heights measured in the same order of each sand spreading experiment, and using the average values ​​of each piston height as each piston height node in the corresponding relationship table; S13, let t Ni represents the i-th t in the N-th sand spreading experiment, N = 1, 2, ..., a; by the formula and Calculate the sand and gravel flow rate b, where T is the average time required from full sand to all sand and gravel flowing out of the sand box, and V represents the maximum sand and gravel capacity of the sand box; S14, through the formula W j = tjb Calculate the amount of sand and gravel that has flowed out each time the piston height is measured W j , where j represents the order of piston height measurement in the sand spreading experiment, j = 0, 1, 2, ..., n; S15, through the formula Calculate the remaining sand amount node C in each sand box in the corresponding relationship table j , the corresponding relationship table is determined according to the remaining sand amount nodes in each sand box and the piston height nodes.

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