A device and method for rapidly detecting the uniformity of bale internal pressure

Abstract

The application belongs to the technical field of agricultural machinery equipment, and particularly relates to a device and a method for rapidly detecting the uniformity of internal pressure of a straw bale. The device comprises a shell, a lead screw, a bottom thrust bearing, a top bearing, a pressure measuring assembly, a bottom support disc, a top limiting disc, a taper head, a motor, a power supply, a control box and a shock absorber. The shock absorber, the control box, the power supply and the motor are sequentially arranged in the upper cavity of the shell from top to bottom. The lead screw is arranged in the lower cavity of the shell, is fixed by the bottom thrust bearing and the top bearing, and is ensured to have only one degree of freedom of rotation along the axis. The lead screw is connected with the power output shaft of the motor through a shaft coupling. The pressure measuring assembly comprises a sliding block, an annular pressure sensor, a limiting ring, a sliding sleeve, a push rod and a pressing block. The device can penetrate into a specific point of the straw bale under external force, and the rapid detection of the uniformity of the internal pressure of the straw bale can be realized through the detection results of multiple points, so as to determine whether a uniform anaerobic environment is formed in the straw bale.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of agricultural machinery equipment, and particularly relates to a device and a method for rapidly detecting the uniformity of internal pressure of a grass bale. BACKGROUND

[0002] The process of making a silage of king grass generally includes cultivation, mowing, crushing, baling, wrapping, storage and feed making. Since the king grass is wrapped by using the stretch film silage technology, a certain amount of silage agent is mixed before wrapping, and fermentation is carried out in an anaerobic environment to inhibit the proliferation of microorganisms and reduce the loss of nutritional value during silage. A large number of studies have shown that increasing the wrapping density is beneficial to reducing the oxygen content and improving the success rate and quality of silage. Therefore, it is of great significance to ensure the uniformity of the density of the grass bale to make the entire grass bale in the same fermentation process and to make the PH value of the silage feed decrease to the appropriate range of 3.8-5.0 as soon as possible. The pressure distribution inside the grass bale can qualitatively reflect the density distribution and the oxygen content distribution. When the uniformity of the internal pressure distribution of the grass bale is high, it also reflects that the internal oxygen content distribution is relatively uniform. However, there is currently no effective means and device to rapidly detect the uniformity of the internal pressure of the grass bale. SUMMARY

[0003] In view of the above technical problems, the present application aims to provide a device and a method for rapidly detecting the uniformity of the internal pressure of a grass bale. The device can penetrate into a specific point of the grass bale under the action of an external force, and the rapid detection of the uniformity of the internal pressure of the grass bale can be realized through the detection results of multiple points, so as to determine whether an anaerobic environment is formed inside the grass bale.

[0004] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0005] A device for rapidly detecting the uniformity of the internal pressure of a grass bale, comprising a shell 11, a lead screw 1, a bottom thrust bearing 2, a top bearing 3, a pressure measuring assembly 21, a bottom support disc 9, a top limiting disc 10, a tapered head 12, a motor 15, a power supply 17, a control box 18 and a shock absorber 19.

[0006] The shell 11 is a hollow cylindrical tube, having a bottom plate and a top plate, and a partition plate arranged in the middle, which separates the shell 11 into an upper cavity and a lower cavity; the bottom plate and the partition plate are both provided with coaxial mounting holes 1104, the bottom thrust bearing 2 is fixed on the mounting hole 1104 of the bottom plate through the bottom support disc 9, and the top bearing 3 is fixed on the mounting hole 1104 of the partition plate through the top limiting disc 10; the tapered head 12 is detachably fixed at the bottom end of the shell 11; the shock absorber 19, the control box 18, the power supply 17 and the motor 15 are arranged in the upper cavity of the shell 11 from top to bottom in sequence; the lead screw 1 is arranged in the lower cavity of the shell 11, is fixed by the bottom thrust bearing 2 and the top bearing 3 together, and ensures that the lead screw 1 has only one degree of freedom of rotation along the axis; the lead screw 1 is connected with the power output shaft of the motor 15 through the shaft coupling 14.

[0007] The surface of the pipe body of the lower part of the shell 11 is provided with an annular groove 1102, and six shell limiting holes 1101 are uniformly distributed on the annular groove 1102 in the circumferential direction and arranged in the radial direction of the pipe body.

[0008] The pressure measuring assembly 21 comprises a sliding block 4, annular pressure sensors 5, a limiting ring 6, a sliding sleeve 7, push rods 8 and pressure blocks 13.

[0009] The sliding block 4 is threadedly connected on the lead screw 1 and can move up and down with the rotation of the lead screw 1; two annular pressure sensors 5 are fixed on the upper and lower ends of the sliding block 4 through the limiting ring 6.

[0010] The sliding sleeve 7 has a circular cross section, a sliding sleeve hole 702 is arranged at the center of the sliding sleeve 7, and six sliding sleeve shafts 701 are uniformly arranged on the edge in the circumferential direction; the sliding sleeve 7 is axially slidably sleeved on the sliding block 4 through the sliding sleeve hole 702 and is located between the two annular pressure sensors 5.

[0011] Each sliding sleeve shaft 701 of the sliding sleeve 7 is hinged with a push rod 8, and each push rod 8 is hinged with a pressure block 13.

[0012] The two ends of the push rod 8 are respectively provided with a push rod hole 801 and a push rod shaft 802, and the push rod 8 is connected with the sliding sleeve shaft 701 through the push rod hole 801.

[0013] The pressing block 13 comprises an arc-shaped plate 1303 and a limiting shaft 1302; the outer end of the limiting shaft 1302 is fixed in the middle of the arc-shaped plate 1303 along the radial direction of the arc-shaped plate 1303, and the inner end of the limiting shaft 1302 is provided with a hinged hole 1301 which is matched and connected with the push rod shaft 802 of the push rod 8; the pressing block 13 is slidably matched with the shell limiting hole 1101 on the shell 11 through the limiting shaft 1302; the arc-shaped plate 1303 has the same center as the annular groove 1102, and the arc-shaped plates 1303 of the six pressing blocks 13 jointly form a circular ring which can be completely accommodated in the annular groove 1102, the included angle θ between the limiting shafts 1302 of the adjacent two pressing blocks 13 is 60°, and when the arc-shaped plate 1303 is completely accommodated in the annular groove 1102, the outer surface of the arc-shaped plate 1303 is coplanar with the surface of the pipe body of the shell 11.

[0014] The power supply 17 is connected with the control box 18, the annular pressure sensor 5 and the motor 15 to provide electric energy; the control box 18 is connected with the motor 15 and the annular pressure sensor 5 to control the motor 15 and receive the stress data collected by the annular pressure sensor 5.

[0015] In the initial state, the sliding block 4 is located at the position closest to or farthest from the conical head 12, and the arc-shaped plate 1303 of the pressing block 13 is completely accommodated in the annular groove 1102 of the shell 11; after the device is inserted into the straw bale, the motor 15 is controlled by the control box 18 to drive the lead screw 1 to rotate forward or reversely at a certain speed, so as to drive the sliding block 4 to move away from or close to the conical head 12, the sliding sleeve 7 moves with the sliding block 4, and simultaneously drives the push rod 8 to push the limiting shaft 1302 of the pressing block 13 outward, so that the arc-shaped plate 1303 leaves the annular groove 1102 to apply a load to the forage, until the push rod 8 is parallel to the shell limiting hole 1101, and the arc-shaped plate 1303 reaches the limit displacement, the loading process is ended; the lead screw 1 continues to rotate with the motor 15 to drive the sliding block 4 to continue to move, and the sliding sleeve 7 drives the push rod 8 to pull the limiting shaft 1302 of the pressing block 13 inward, so that the arc-shaped plate 1303 completely returns to the annular groove 1102 to complete the unloading process; during the loading and unloading processes, the annular pressure sensor 5 collects the stress data and transmits it to the control box 18, and the control box 18 obtains the internal pressure characteristic value of the straw bale according to the stress data.

[0016] The shock absorber 19 is provided between the control box 18 and the power supply 17, between the control box 18 and the motor 15, and between the power supply 17 and the motor 15.

[0017] The outer end surface of the top plate of the shell 11 is provided with a rubber pad 20 for reducing the measurement error caused by knocking vibration.

[0018] The tubular surface of the lower part of the shell 11 is provided with a taper head mounting pipe thread 1103; the taper head 12 comprises a mounting part 1201 and a penetration taper surface part 1203, the inner surface of the mounting part 1201 is provided with a shell mounting pipe thread 1202 matched with the taper head mounting pipe thread 1103; after the taper head 12 is threadedly connected with the shell 11, the outer surface of the mounting part 1202 is coplanar with the tubular surface of the shell 11.

[0019] The included angle γ between the left end surface and the right end surface of the arc-shaped plate 1303 is 50°, which prevents grass from entering the annular groove 1102 when the arc-shaped plate 1303 is retracted, so that the arc-shaped plate 1303 cannot be completely retracted.

[0020] A method for rapidly detecting the internal pressure uniformity of a grass bale by using the rapid detection device for the internal pressure uniformity of a grass bale, comprising the following steps:

[0021] S1, determining a grass bale detection point,

[0022] A vertical circular cross section perpendicular to the central axis is taken every certain distance from the bottom surface along the central axis of the grass bale, a pair of mutually perpendicular diameters on the cross section are arbitrarily taken, a detection point is taken every certain distance along the two diameters from the center of the circle as the starting point, until the outer contour of the circular cross section, no detection point is taken on the outer contour, and the total number of detection points is denoted as n.

[0023] S2, collecting internal pressure data of the grass bale;

[0024] The rapid detection device for the internal pressure uniformity of a grass bale is inserted into the grass bale at an arbitrary angle in a knocking manner, so that the pressing block 13 of the pressure measuring assembly 21 reaches the selected detection points in turn;

[0025] The motor 15 is controlled by the control box 18 to drive the lead screw 1 to rotate forward or reversely at a certain speed, so as to drive the sliding block 4 to move away from or close to the taper head 12, the sliding sleeve 7 moves with the sliding block 4, and at the same time drives the push rod 8 to push the limiting shaft 1302 of the pressing block 13 outward, so that the arc-shaped plate 1303 leaves the annular groove 1102 and loads the forage, until the push rod 8 is parallel to the shell limiting hole 1101, and the arc-shaped plate 1303 reaches the limit displacement, and the loading process is ended; the lead screw 1 continues to rotate with the motor 15, drives the sliding block 4 to continue to move, and the sliding sleeve 7 drives the push rod 8 to pull the limiting shaft 1302 of the pressing block 13 inward, so that the arc-shaped plate 1303 completely returns to the annular groove 1102, and the unloading process is completed; during the loading and unloading processes, the annular pressure sensor 5 collects the stress data and transmits them to the control box 18, the control box 18 converts the pressure peak value F i of each detection point into a pressure characteristic value p i by formula 1, i=1, 2, 3,..., n.

[0026]

[0027] In Formula 1, p i Let be the pressure characteristic value of the i-th detection point, in Pa and F. i Let A be the peak pressure at the i-th detection point, in N, and let A be the area of ​​the arc-shaped plate 1303, in m². 2 ;

[0028] S3. Calculation of internal pressure uniformity of straw bales;

[0029] S3.1 Calculate the average pressure characteristic value of all detection points using Formula 2:

[0030]

[0031] In formula 2, p is the average of the pressure characteristic values ​​at all detection points, in Pa. i Let be the pressure characteristic value of the i-th detection point, in Pa; n is the total number of detection points.

[0032] S3.2 Calculate the standard deviation of all pressure characteristic values ​​using Formula 3:

[0033]

[0034] In Formula 3, σ is the standard deviation of all pressure characteristic values. The smaller the value of σ, the more uniform the internal pressure environment of the straw bale. p is the average of the pressure characteristic values ​​at all detection points, in Pa. i Let be the pressure characteristic value of the i-th detection point, in Pa; n is the total number of detection points.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] 1. The device is small in size, easy to carry, and simple to operate. It can quickly detect the internal pressure uniformity of straw bales anywhere, especially in the field.

[0037] 2. Except for the insertion and removal devices, the entire testing process is intelligently controlled, greatly reducing manpower input;

[0038] 3. The cone head is replaceable, which not only extends the service life of the device, but also allows for the selection of appropriate cone heads based on the type and physical characteristics of the bales, thus adapting to different testing environments and monitoring objects;

[0039] 4. The included angle between the left and right end faces of the arc plate is 50° to prevent grass from entering the ring groove when the arc plate retracts, which would prevent the pressure block from returning to its initial position completely. Attached Figure Description

[0040] Figure 1This is a cross-sectional structural schematic diagram of the rapid detection device for internal pressure uniformity of straw bales according to the present invention.

[0041] Figure 2 This is a schematic diagram of the lower structure of the shell 11;

[0042] Figure 3 This is a schematic diagram of the structure of the cone head 12;

[0043] Figure 4 This is a three-dimensional structural diagram of the pressure measuring assembly 21;

[0044] Figure 5 This is a front view structural schematic diagram of the pressure measurement assembly 21;

[0045] Figure 6 Here is a schematic diagram of the structure of the sliding sleeve 7;

[0046] Figure 7 Here is a schematic diagram of the push rod 8;

[0047] Figure 8 This is a schematic diagram of the structure of the pressure block 13;

[0048] Figure 9 This is a schematic diagram of the assembly of the pressure block 13 and the housing 11;

[0049] Figure 10 This is a schematic diagram of the first initial state of the pressure measurement assembly 21;

[0050] Figure 11 This is a schematic diagram of the loading state of the pressure testing assembly 21;

[0051] Figure 12 This is a schematic diagram of the second initial state of the pressure measurement assembly 21.

[0052] The reference numerals in the attached figures are:

[0053] 1. Lead screw 2. Bottom thrust bearing

[0054] 3 top bearings 4 sliders

[0055] 5. Ring pressure sensor; 6. Limiting ring

[0056] 7 Sliding Sleeves

[0057] 701 Sliding sleeve shaft, 702 Sliding sleeve hole

[0058] 8 putters

[0059] 801 push rod hole, 802 push rod shaft

[0060] 9. Bottom support plate 10. Top limit plate

[0061] 11 Casing

[0062] 1101 Housing limiting hole; 1102 Annular groove

[0063] 1103 Tapered head mounting pipe thread; 1104 Mounting hole

[0064] 12 cones

[0065] 1201 Mounting part 1202 Housing mounting pipe thread

[0066] 1203 Penetration into the Conical Face

[0067] 13 blocks

[0068] 1301 Hinge Hole 1302 Limiting Shaft

[0069] 1303 curved plate

[0070] 14 Couplings 15 Motors

[0071] 16 Shock-absorbing pads 17 Power supply

[0072] 18 Control box 19 Shock absorber

[0073] 20 Rubber Pad 21 Pressure Measurement Assembly Detailed Implementation

[0074] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0075] like Figure 1 As shown, a rapid detection device for the internal pressure uniformity of a hay bale includes a housing 11, a lead screw 1, a bottom thrust bearing 2, a top bearing 3, a pressure measuring assembly 21, a bottom support plate 9, a top limiting plate 10, a cone head 12, a motor 15, a power supply 17, a control box 18, and a shock absorber 19.

[0076] The housing 11 is a hollow cylindrical tube with a bottom plate, a top plate, and a partition plate in the middle, which divides the housing 11 into an upper cavity and a lower cavity. Both the bottom plate and the partition plate have coaxial mounting holes 1104. The bottom thrust bearing 2 is fixed to the mounting hole 1104 on the bottom plate via a bottom support plate 9, and the top bearing 3 is fixed to the mounting hole 1104 on the partition plate via a top limiting plate 10. The cone head 12 is detachably fixed to the bottom end of the housing 11. The shock absorber 19, control box 18, power supply 17, and motor 15 are arranged sequentially from top to bottom in the upper cavity of the housing 11. The lead screw 1 is arranged in the lower cavity of the housing 11 and is fixed by the bottom thrust bearing 2 and the top bearing 3, ensuring that the lead screw 1 has only one degree of freedom to rotate along its axis. The lead screw 1 is connected to the power output shaft of the motor 15 via a coupling 14.

[0077] Preferably, shock-absorbing pads 16 are provided between the shock absorber 19 and the control box 18, between the control box 18 and the power supply 17, and between the power supply 17 and the motor 15. The shock absorber 19 and the shock-absorbing pads 16 dampen the impact penetration process.

[0078] Preferably, the outer end face of the top plate of the housing 11 is provided with a rubber pad 20 to reduce measurement errors caused by impact vibration.

[0079] Preferably, such as Figure 2 As shown, the lower part of the casing 11 has a tapered mounting pipe thread 1103 on its tube surface. (As indicated...) Figure 3 As shown, the cone 12 includes a mounting part 1201 and a conical part 1203. The inner surface of the mounting part 1201 is provided with a housing mounting pipe thread 1202 that mates with the cone mounting pipe thread 1103. After the cone 12 is threadedly connected to the housing 11, the outer surface of the mounting part 1202 is coplanar with the tube surface of the housing 11.

[0080] like Figure 2 As shown, the lower part of the casing 11 has an annular groove 1102 on the tube surface, and six casing limiting holes 1101 are evenly distributed circumferentially along the radial direction of the tube in the annular groove 1102.

[0081] like Figures 4 to 12 As shown, the pressure measuring assembly 21 includes a slider 4, an annular pressure sensor 5, a limiting ring 6, a sliding sleeve 7, a push rod 8, and a pressure block 13.

[0082] The slider 4 is threaded onto the lead screw 1 and can move up and down as the lead screw 1 rotates. Two annular pressure sensors 5 are fixed to the upper and lower ends of the slider 4 by limiting rings 6.

[0083] like Figure 6 As shown, the cross-section of the sliding sleeve 7 is circular, with a sliding sleeve hole 702 at the center and six sliding sleeve shafts 701 evenly arranged circumferentially at the edge; the sliding sleeve 7 is axially slidably sleeved on the slider 4 through the sliding sleeve hole 702 and is located between the two annular pressure sensors 5.

[0084] like Figure 4 and Figure 5 As shown, a push rod 8 is hinged to each sliding shaft 701 of the sliding sleeve 7, and each push rod 8 is hinged to a pressure block 13.

[0085] like Figure 7 As shown, the push rod 8 has a push rod hole 801 and a push rod shaft 802 at both ends, and the push rod 8 is connected to the sliding sleeve shaft 701 through the push rod hole 801.

[0086] like Figure 8As shown, the pressure block 13 includes an arc-shaped plate 1303 and a limiting shaft 1302; the outer end of the limiting shaft 1302 is fixedly connected to the middle of the arc-shaped plate 1303 radially, and the inner end of the limiting shaft 1302 is provided with a hinge hole 1301 that is connected to the push rod shaft 802 of the push rod 8; the pressure block 13 is slidably engaged with the housing limiting hole 1101 on the housing 11 through the limiting shaft 1302; the arc-shaped plate 1303 and the annular groove 1102 are concentric, and the arc-shaped plates 1303 of the six pressure blocks 13 together form a ring that can be completely accommodated in the annular groove 1102. The included angle θ between the limiting shafts 1302 of two adjacent pressure blocks 13 is 60°, and when the arc-shaped plate 1303 is completely accommodated in the annular groove 1102, the outer surface of the arc-shaped plate 1303 is coplanar with the tube surface of the housing 11.

[0087] Preferably, the included angle γ between the left and right end faces of the arc plate 1303 is 50° to prevent grass from entering the annular groove 1102 when the arc plate 1303 is retracted, which would prevent the arc plate 1303 from being completely retracted.

[0088] The power supply 17 is connected to the control box 18, the annular pressure sensor 5, and the motor 15 to provide electrical energy; the control box 18 is connected to the motor 15 and the annular pressure sensor 5 to control the motor 15 and receive the force data collected by the annular pressure sensor 5.

[0089] like Figure 10 and Figure 12 As shown, in the initial state, the slider 4 is located at the position closest to or farthest from the cone head 12, and the arc-shaped plate 1303 of the pressure block 13 is completely accommodated in the annular groove 1102 of the housing 11. When the device is inserted into the bale, the motor 15 is controlled by the control box 18 to drive the lead screw 1 to rotate forward or backward at a certain speed, thereby moving the slider 4 away from or closer to the cone head 12. The sliding sleeve 7 moves with the slider 4, and at the same time, it drives the push rod 8 to push the limiting shaft 1302 of the pressure block 13 outward, so that the arc-shaped plate 1303 leaves the annular groove 1102. Figure 10 As shown, a load is applied to the hay until the push rod 8 is parallel to the housing limit hole 1101 and the arc plate 1303 reaches its limit displacement, at which point the loading process ends; the lead screw 1 continues to rotate with the motor 15, driving the slider 4 to continue moving, and the sliding sleeve 7 drives the push rod 8 to pull the limit shaft 1302 of the pressure block 13 inward, so that the arc plate 1303 completely returns to the annular groove 1102, completing the unloading process; during the loading and unloading process, the annular pressure sensor 5 collects the force data and transmits it to the control box 18, and the control box 18 obtains the internal pressure characteristic value of the hay bale based on the force data.

[0090] A method for rapidly detecting the internal pressure uniformity of a straw bale using the aforementioned rapid detection device includes the following steps:

[0091] S1. Determine the bale inspection point.

[0092] Take a circular cross section perpendicular to the central axis of the hay bale every 20cm from the bottom. Take a pair of mutually perpendicular diameters on the cross section. Starting from the center of the circle, take a test point every 10cm along the two diameters until the outer contour of the circular cross section. Do not take test points on the outer contour. The total number of test points is recorded as n.

[0093] S2. Data collection of internal pressure in straw bales;

[0094] The rapid detection device for uniform internal pressure of straw bales is inserted into the straw bale at any angle by tapping, so that the pressure block 13 of the pressure testing assembly 21 reaches the selected testing points in sequence.

[0095] The control box 18 controls the motor 15 to drive the lead screw 1 to rotate forward or backward at a certain speed, thereby driving the slider 4 to move away from or towards the cone head 12. The sliding sleeve 7 moves with the slider 4, and at the same time drives the push rod 8 to push the limiting shaft 1302 of the pressure block 13 outward, so that the arc plate 1303 leaves the annular groove 1102, applying a load to the grass until the push rod 8 is parallel to the housing limiting hole 1101 and the arc plate 1303 reaches its limit displacement, ending the loading process. The lead screw 1 continues to rotate with the motor 15, driving the slider 4 to continue moving. The sliding sleeve 7 drives the push rod 8 to pull the limiting shaft 1302 of the pressure block 13 inward, so that the arc plate 1303 completely returns to the annular groove 1102, completing the unloading process. During the loading and unloading process, the annular pressure sensor 5 collects the force data and transmits it to the control box 18. The control box 18 uses formula 1 to calculate the pressure peak value F at each detection point. i Converted into pressure characteristic value p i , i = 1, 2, 3, ..., n;

[0096]

[0097] In Formula 1, p i Let be the pressure characteristic value of the i-th detection point, in Pa and F. i Let A be the peak pressure at the i-th detection point, in N, and let A be the area of ​​the arc-shaped plate 1303, in m². 2 ;

[0098] S3. Calculation of internal pressure uniformity of straw bales;

[0099] S3.1 Calculate the average pressure characteristic value of all detection points using Formula 2:

[0100]

[0101] In formula 2, p is the average of the pressure characteristic values ​​at all detection points, in Pa. iLet be the pressure characteristic value of the i-th detection point, in Pa; n is the total number of detection points.

[0102] S3.2 Calculate the standard deviation of all pressure characteristic values ​​using Formula 3:

[0103]

[0104] In Formula 3, σ is the standard deviation of all pressure characteristic values. The smaller the value of σ, the more uniform the internal pressure environment of the straw bale. p is the average of the pressure characteristic values ​​at all detection points, in Pa. i Let be the pressure characteristic value of the i-th detection point, in Pa; n is the total number of detection points.

[0105] In a preferred embodiment, a round silage bale with a length of 1000mm and a diameter of 1000mm is selected. A circular cross-section perpendicular to the central axis is taken every 20cm from the bottom surface along the central axis of the bale. A set of mutually perpendicular diameters are arbitrarily selected on this cross-section. Starting from the center of the circle, a test point is taken every 10cm along the two diameters until the outer contour of the circular cross-section is reached. No test points are taken on the outer contour, for a total of 68 test points.

[0106] The rapid pressure uniformity testing device inside the hay bale is inserted into the hay bale at any angle, so that the pressure block 13 of the pressure measuring assembly 21 sequentially reaches the selected testing points for testing. The pressure peak value at each testing point is recorded as F. i , i = 1, 2, 3, ..., 68.

[0107] Control box 18 converts the pressure peak value into a pressure characteristic value; it calculates the average value of the characteristic values ​​at all detection points. Calculate the standard deviation of all eigenvalues: The smaller the σ value, the more uniform the internal pressure environment of the straw bale.

Claims

1. A rapid detection device for the internal pressure uniformity of straw bales, characterized in that, The device includes a housing (11), a lead screw (1), a bottom thrust bearing (2), a top bearing (3), a pressure measuring assembly (21), a bottom support plate (9), a top limiting plate (10), a cone head (12), a motor (15), a power supply (17), a control box (18), and a shock absorber (19). The housing (11) is a hollow cylindrical tube with a bottom plate and a top plate, and a partition plate in the middle, which divides the housing (11) into an upper cavity and a lower cavity; both the bottom plate and the partition plate have coaxial mounting holes (1104); the bottom thrust bearing (2) is fixed to the mounting hole (1104) of the bottom plate by a bottom support plate (9); the top bearing (3) is fixed to the mounting hole (1104) of the partition plate by a top limiting plate (10); the cone head (12) The shock absorber (19), control box (18), power supply (17) and motor (15) are arranged sequentially from top to bottom in the upper cavity of the housing (11); the lead screw (1) is arranged in the lower cavity of the housing (11), and is fixed by the bottom thrust bearing (2) and the top bearing (3), ensuring that the lead screw (1) has only one degree of freedom to rotate along the axis; the lead screw (1) is connected to the power output shaft of the motor (15) through the coupling (14); The lower part of the shell (11) has an annular groove (1102) on the tube surface, and six shell limiting holes (1101) are evenly distributed in the annular groove (1102) along the radial direction of the tube. The pressure measuring assembly (21) includes a slider (4), an annular pressure sensor (5), a limiting ring (6), a sliding sleeve (7), a push rod (8), and a pressure block (13); The slider (4) is threadedly connected to the lead screw (1) and can move up and down with the rotation of the lead screw (1); two annular pressure sensors (5) are fixed to the upper and lower ends of the slider (4) through limiting rings (6); The cross-section of the sliding sleeve (7) is circular, with a sliding sleeve hole (702) at the center and six sliding sleeve shafts (701) evenly arranged circumferentially at the edge; the sliding sleeve (7) is axially slidably sleeved on the slider (4) through the sliding sleeve hole (702) and is located between the two annular pressure sensors (5). A push rod (8) is hinged to each sliding shaft (701) of the sliding sleeve (7), and each push rod (8) is hinged to a pressure block (13); The push rod (8) has a push rod hole (801) and a push rod shaft (802) at both ends, and the push rod (8) is connected to the sliding sleeve shaft (701) through the push rod hole (801); The pressure block (13) includes an arc-shaped plate (1303) and a limiting shaft (1302); the outer end of the limiting shaft (1302) is fixedly connected to the middle part of the arc-shaped plate (1303) along the radial direction of the arc-shaped plate (1303), and the inner end of the limiting shaft (1302) is provided with a hinge hole (1301) that is connected to the push rod shaft (802) of the push rod (8); the pressure block (13) slides through the limiting shaft (1302) and the housing limiting hole (1101) on the housing (11). The arc plate (1303) and the annular groove (1102) are concentric. The arc plates (1303) of the six pressure blocks (13) together form a ring that can be completely contained in the annular groove (1102). The included angle θ between the limiting shafts (1302) of two adjacent pressure blocks (13) is 60°. When the arc plate (1303) is completely contained in the annular groove (1102), the outer surface of the arc plate (1303) is coplanar with the tube surface of the shell (11). The included angle γ between the left and right end faces of the arc plate (1303) is 50° to prevent grass from entering the annular groove (1102) when the arc plate (1303) is retracted, which would prevent the arc plate (1303) from being completely retracted. The power supply (17) is connected to the control box (18), the ring pressure sensor (5) and the motor (15) to provide electrical energy; the control box (18) is connected to the motor (15) and the ring pressure sensor (5) to control the motor (15) and receive the force data collected by the ring pressure sensor (5); In the initial state, the slider (4) is located at the position closest to or farthest from the cone (12), and the arc plate (1303) of the pressure block (13) is completely contained in the annular groove (1102) of the housing (11). After the device is inserted into the bale, the motor (15) is controlled by the control box (18) to drive the lead screw (1) to rotate forward or backward at a certain speed, thereby driving the slider (4) to move away from or closer to the cone (12). The sliding sleeve (7) moves with the slider (4), and at the same time drives the push rod (8) to push the limiting shaft (1302) of the pressure block (13) outward, so that the arc plate (1303) leaves the annular groove (1102). The load is applied to the hay until the push rod (8) is parallel to the housing limit hole (1101) and the arc plate (1303) reaches its limit displacement, at which point the loading process ends; the lead screw (1) continues to rotate with the motor (15), driving the slider (4) to continue moving, and the sliding sleeve (7) drives the push rod (8) to pull the limit shaft (1302) of the pressure block (13) inward, so that the arc plate (1303) returns completely to the annular groove (1102), completing the unloading process; during the loading and unloading process, the annular pressure sensor (5) collects the force data and transmits it to the control box (18), and the control box (18) obtains the internal pressure characteristic value of the hay bale based on the force data.

2. The rapid detection device for internal pressure uniformity of straw bales according to claim 1, characterized in that, Shock-absorbing pads (16) are provided between the shock absorber (19) and the control box (18), between the control box (18) and the power supply (17), and between the power supply (17) and the motor (15).

3. The rapid detection device for internal pressure uniformity of straw bales according to claim 1, characterized in that, The outer end face of the top plate of the housing (11) is provided with a rubber pad (20).

4. The rapid detection device for internal pressure uniformity of straw bales according to claim 1, characterized in that, The lower part of the housing (11) has a conical mounting pipe thread (1103) on its tube surface; the conical head (12) includes a mounting part (1201) and a conical part (1203), and the inner surface of the mounting part (1201) is provided with a housing mounting pipe thread (1202) that mates with the conical mounting pipe thread (1103); after the conical head (12) is threadedly connected to the housing (11), the outer surface of the mounting part (1201) is coplanar with the tube surface of the housing (11).

5. A method for rapidly detecting the internal pressure uniformity of a hay bale using the rapid detection device for internal pressure uniformity as described in any one of claims 1-4, characterized in that, The method includes the following steps: S1. Determine the bale inspection point. Starting from the bottom of the hay bale, take a circular cross section perpendicular to the central axis at regular intervals. Take a pair of mutually perpendicular diameters on the cross section. Starting from the center of the circle, take a test point at regular intervals along the two diameters until the outer contour of the circular cross section is reached. No test points are taken on the outer contour. The total number of test points is recorded as n. S2. Data collection of internal pressure in straw bales; The rapid detection device for uniform internal pressure of straw bales is inserted into the straw bales at any angle by tapping, so that the pressure block (13) of the pressure measuring assembly (21) reaches the selected detection points in sequence; The control box (18) controls the motor (15) to drive the lead screw (1) to rotate forward or backward at a certain speed, thereby driving the slider (4) to move away from or towards the cone head (12). The sliding sleeve (7) moves with the slider (4), and at the same time drives the push rod (8) to push the limiting shaft (1302) of the pressure block (13) outward, so that the arc plate (1303) leaves the annular groove (1102) and applies a load to the grass until the push rod (8) is parallel to the housing limiting hole (1101) and the arc plate (1303) moves away from the annular groove (1102). When the limit displacement is reached, the loading process ends; the lead screw (1) continues to rotate with the motor (15), driving the slider (4) to continue moving, and the sliding sleeve (7) drives the push rod (8) to pull the limit shaft (1302) of the pressure block (13) inward, so that the arc plate (1303) completely returns to the annular groove (1102), completing the unloading process; during the loading and unloading process, the annular pressure sensor (5) collects the force data and transmits it to the control box (18), and the control box (18) calculates the pressure peak value F at each detection point using formula 1. i Converted into pressure characteristic value p i , i = 1, 2, 3, ..., n; In Formula 1, p i Let be the pressure characteristic value of the i-th detection point, in Pa and F. i Let A be the peak pressure at the i-th detection point, in N, and let A be the area of ​​the arc-shaped plate (1303), in m². 2 ; S3. Calculation of internal pressure uniformity of straw bales; S3.1 Calculate the average pressure characteristic value of all detection points using Formula 2: In formula 2, p is the average of the pressure characteristic values ​​at all detection points, in Pa. i Let be the pressure characteristic value of the i-th detection point, in Pa; n is the total number of detection points. S3.2 Calculate the standard deviation of all pressure characteristic values ​​using Formula 3: In Formula 3, σ is the standard deviation of all pressure characteristic values. The smaller the value of σ, the more uniform the internal pressure environment of the straw bale. p is the average of the pressure characteristic values ​​at all detection points, in Pa. i Let be the pressure characteristic value of the i-th detection point, in Pa; n is the total number of detection points.

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