Variable-rigidity connecting assembly, machine tail connecting device and using method

Abstract

The invention discloses a variable-rigidity connecting assembly, a machine tail connecting device and a using method. The variable-rigidity connecting assembly comprises a supporting body, a permanent magnet, a magnet exciting coil, an elastic sleeve and a magnetic current layer. The magnet exciting coil located on the outer side of the permanent magnet can generate a magnetic field in the same direction or in the opposite direction with the permanent magnet after being electrified, the magnetic current layer acts on the elastic sleeve under the influence of the magnetic field, the elastic sleeve is subjected to expansion and retraction deformation, variable-rigidity controllable connection between rigidity and flexibility at the connecting position is achieved, and the variable-rigidity permanent magnet motor is suitable for different use environments and has good application prospects. The problems of force suffocation, jamming and the like or the deformation of a connecting position are avoided; according to the tail connecting device, a connecting assembly with variable rigidity is arranged in a positioning hole formed in the butt joint of a first belt frame and a second belt frame in a sleeved mode, variable rigidity connection between rigidity and flexibility between the self-moving tail belt frames is achieved, control and adjustment can be conducted according to different working conditions, and the problems of force suffocation, jamming and the like are avoided.

Description

Technical Field

[0001] The invention relates to a belt conveyor self-moving tail technology, belongs to the field of coal mine auxiliary transportation, and specifically relates to a variable stiffness connection component, a tail connection device and a use method. Background Art

[0002] The self-moving tail of the belt conveyor is a mobile device used in conjunction with the belt conveyor and the transfer machine in the fully mechanized mining and excavation working face of a coal mine. As a connecting device between the belt conveyor and the transfer machine, it can follow the advance of the roadheader in real time according to the operation of the roadheader. It is suitable for high-yield and high-efficiency working faces and meets the needs of rapid advancement. It is an important equipment for the roadheader to transport raw coal in the production of the coal mine excavation working face.

[0003] At present, according to functional requirements, the overall structure of the tail of the self-moving machine at the excavation face of a coal mine can be divided into a redirection section, a walking section, a marking section, a power section, a loading section, etc., and each section is rigidly fixedly connected by a pin shaft, that is, adjacent sections are provided with ears that can be docked, and the pin shaft is inserted in the ear seat and limited by the docking surface of each section to ensure the horizontal connection between adjacent sections; however, the tunnel conditions of the coal mine excavation face are extremely harsh, the working conditions are complex, and the bottom plate fluctuates greatly. The rigid pin shaft connection cannot be adjusted according to the use environment, which can easily cause problems such as "holding strength" and "stuck" between the sections of the equipment, and even cause the pin shaft to break, making it difficult to adapt to the harsh bottom plate conditions of the excavation tunnel; therefore, workers are often required to participate in the operation of the entire set of equipment to assist in solving the above problems, but this will not only reduce production efficiency, but also pose a risk of threatening the lives of workers;

[0004] For example, the Chinese utility model patent with publication number CN219602304U: A walking self-moving tail device, its disclosure content: a guide rail connecting ear 37 and a guide rail connecting plate 36 are provided at the end of the first section guide rail 29, one end of the guide rail connecting ear 37 is welded and fixed to the first section guide rail 29, and the other end is connected to the guide rail connecting plate 36 by a bolt assembly, the guide rail connecting plate 36 is welded and fixed to one end of the middle section guide rail 31, and the other end of the middle section guide rail 31 is connected to another guide rail connecting ear 37 and another guide rail connecting plate 36 by welding, the other guide rail connecting ear 37 is connected to the other guide rail connecting plate 36 by a bolt assembly, and the other guide rail connecting plate 36 is welded and fixed to the tail section guide rail 39;

[0005] That is, when adjacent guide plates in the tail of the self-propelled machine are connected, they are mainly done through welding and bolt assemblies. When the bottom is in an uneven state, this rigid connection cannot be adjusted according to the use environment, and it is easy to cause problems such as "stuck force" and "stuck", or cause the guide plate to deform. Summary of the invention

[0006] The purpose of the present invention is to provide a variable stiffness connection component with a simple and compact structure, which can realize a variable stiffness controllable connection between rigidity and flexibility at the connection position, is suitable for different usage environments, and avoids problems such as stiffness holding and jamming, or deformation at the connection position.

[0007] To achieve the above purpose, the variable stiffness connection component includes:

[0008] Support body;

[0009] A permanent magnet is located inside the support body and has an excitation coil on the outside thereof for passing current to generate a bidirectional magnetic field;

[0010] The excitation coil is arranged outside the permanent magnet and configured to pass current to generate a magnetic field in the same direction or opposite direction as the permanent magnet;

[0011] The elastic sleeve is sleeved on the outer side of the support body and forms a sealed annular cavity with the peripheral side of the support body;

[0012] The magnetosphere is located in the annular cavity and is affected by the magnetic field to act on the elastic sleeve, causing the elastic sleeve to expand and contract.

[0013] In some examples of the present invention, the magnetorheological layer includes a magnetorheological fluid and a magnetorheological elastomer arranged in an annular shape;

[0014] Compared with magnetorheological fluid, magnetorheological elastomer is close to the center of permanent magnet.

[0015] In some examples of the present invention, the excitation coils are in multiple groups; the multiple groups of excitation coils are evenly spaced and distributed around the center of the permanent magnet;

[0016] Each excitation coil is connected to a controller, which independently controls the magnitude and direction of the current flowing into the excitation coil.

[0017] In some examples of the present invention, a cavity is provided at the center of the support body and one end of the cavity is sealed by a first cover plate;

[0018] The permanent magnet and the excitation coil are both contained in the cavity, and the center of the permanent magnet is consistent with the center of the cavity;

[0019] The elastic sleeve is connected to both sides of the support body and forms a closed annular cavity through a sealing component.

[0020] In some examples of the present invention, the sealing assembly may be a pair of sealing rings;

[0021] One sealing ring is close to the connection between the elastic sleeve and the support body; the other sealing ring is arranged between the peripheral side of the first cover plate and the inner wall of the elastic sleeve, or installed between the peripheral side of the support body and the inner wall of the elastic sleeve.

[0022] In some examples of the present invention, both ends of the elastic sleeve are hard ring bodies.

[0023] The present invention also aims to provide a tail connection device, which generates a magnetic field in the same or opposite direction as the permanent magnet by controlling the power supply of the excitation coil, so that the magnetorheological elastomer and the magnetorheological fluid are deformed by the magnetic field, thereby realizing a variable stiffness connection between the rigidity and flexibility of the self-moving tail belt frame, and can be controlled and adjusted according to different working conditions to avoid problems such as holding force and jamming.

[0024] A tail connection device, comprising the above-mentioned variable stiffness connection assembly;

[0025] The variable-rigidity connection component is sleeved in the positioning hole where the first belt rack and the second belt rack are butted against each other.

[0026] In some examples of the present invention, a sensing component connected to the controller is also included;

[0027] The sensing component is a displacement sensor, and the displacement sensor is configured to detect the height difference between the first belt frame and the second belt frame;

[0028] When the height difference exceeds a certain range, the controller controls the excitation coil to energize to generate a magnetic field opposite to that of the permanent magnet;

[0029] or:

[0030] The sensing components are a plurality of pressure sheet sensors, which are arranged in positioning holes where the variable stiffness connection assembly contacts the first belt frame and the second belt frame, and are configured to detect the circumferential contact pressure of the positioning holes;

[0031] Multiple pressure plate sensors transmit pressure signals to the controller. When the pressure difference exceeds a certain range, the controller controls the current of the adjacent excitation coil at the pressure plate sensor that detects the relatively large pressure, so that the excitation coil generates a magnetic field opposite to the permanent magnet.

[0032] In some examples of the present invention, a second cover plate is also included;

[0033] The second cover plate is mounted on the first cover plate by means of bolts, and axially limits the first belt frame and the second belt frame by extrusion.

[0034] A method for using a tail connection device comprises the following steps:

[0035] S1, inserting the variable stiffness connection assembly into the positioning hole where the first belt rack and the second belt rack are connected;

[0036] Initially, under the action of the permanent magnet, the magnetorheological elastomer and the magnetorheological fluid are in a certain state, so that the elastic sleeve has a certain rigidity;

[0037] S2, when the tail of the self-moving machine is in a good working condition on the bottom plate, the variable stiffness connection component can provide a better rigid connection, multiple excitation coils generate a magnetic field in the same direction as the permanent magnet, the magnetorheological elastomer deforms more and squeezes the magnetorheological fluid, and the magnetorheological fluid is converted into a high-viscosity, low-fluidity solid state, so that the elastic sleeve increases the contact with the positioning hole, completing the rigid connection;

[0038] S3, when the tail of the self-moving machine is in a poor working condition of the base plate, the signal is transmitted to the controller through the induction component, and different excitation coils are controlled respectively, so that some excitation coils generate a magnetic field opposite to the permanent magnet, and the magnetorheological elastomer at the corresponding circumferential position is deformed and retracted, and at the same time, the magnetorheological fluid is converted into a low-viscosity liquid state, so that the circumferential position of the elastic sleeve is reduced. The interaction with the positioning hole is guaranteed to a certain extent, and the rigid connection is stable and has a certain degree of flexible adjustable gap;

[0039] Alternatively, all the excitation coils generate a magnetic field opposite to the permanent magnet and form a reverse magnetic field in the magnetosphere, so that the elastic sleeve as a whole reduces the interaction with the positioning hole, thereby completing a flexible connection.

[0040] Compared with the prior art, the variable stiffness connection assembly generates a magnetic field in the same or opposite direction as the permanent magnet when the excitation coil is energized, so that the permanent magnet and the excitation coil can be energized in a two-stage coordinated manner. Under the influence of the magnetic field, the magnetosphere acts on the elastic sleeve to cause the elastic sleeve to expand and retract, thereby realizing a variable stiffness controllable connection between the rigidity and flexibility at the connection position, avoiding problems such as holding force and jamming, and is suitable for variable stiffness connection between the tail belt racks of self-propelled machines, meeting the harsh floor conditions of the roadway.

[0041] Since the magnetorheological fluid and the magnetorheological elastomer are combined with each other and adjusted by the magnetic field, on the one hand, the magnetorheological elastomer can effectively avoid the sedimentation and agglomeration of magnetic particles, thereby improving the stability and bearing strength of the connection. On the other hand, the magnetorheological fluid is squeezed and changes between liquid and solid under the influence of the magnetic field, so that the elastic sleeve can be adjusted between rigid and flexible connection, and this flexible connection enables the two connected sections to rotate and move, and the degree of rigid or flexible connection can be controlled by the magnetic field.

[0042] Since multiple groups of excitation coils are evenly spaced around the center of the permanent magnet, and the controller independently controls the magnitude and direction of the current passed through each excitation coil, the magnetic field generated by the permanent magnet can be enhanced or weakened in the local area, and the state of the magnetosphere at the corresponding position changes, causing the elastic sleeve to deform at the corresponding position, thereby ensuring the stability of the rigid connection to a certain extent and having a certain degree of flexible adjustable gap. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1is an overall front view of the variable stiffness connection assembly of the present invention;

[0044] Figure 2 yes Figure 1 Cross-section at the middle AA position;

[0045] Figure 3 This is the overall connection front view of the tail connection device of the present invention;

[0046] Figure 4 It is a schematic diagram of the overall connection of the tail connection device of the present invention;

[0047] In the figure: 10, support body;

[0048] 20. Permanent magnet;

[0049] 30. Elastic sleeve;

[0050] 41. Magnetorheological elastomer, 42. Magnetorheological fluid;

[0051] 50. Excitation coil;

[0052] 61. a first cover plate, 62. a second cover plate, 63. a sealing assembly;

[0053] 70. First belt rack, 80. Second belt rack. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the technical solution of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described in conjunction with the drawings of specific embodiments of the present invention. The same figure marks in the drawings represent the same parts. It should be noted that the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described 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.

[0055] Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the present invention belongs. The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not necessarily indicate a quantity limitation. Words such as "include" or "comprise" mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0056] like Figure 1 As shown, the variable stiffness connection component includes:

[0057] Support body 10;

[0058] The permanent magnet 20 is located inside the support body 10, and an excitation coil 50 is provided on the outside for passing current to generate a bidirectional magnetic field;

[0059] The elastic sleeve 30 is sleeved on the outer side of the support body 10 and forms a sealed annular cavity with the surrounding side of the support body 10;

[0060] The magnetosphere, located in the annular cavity, is affected by the magnetic field and acts on the elastic sleeve 30 to deform it;

[0061] Specifically, the support body 10 is the main supporting structure of the variable stiffness connection assembly, and the whole body can adopt a pin, bolt type or other structural form;

[0062] The permanent magnet 20 is located in the support body 10, and is a magnetic material with spontaneous magnetization characteristics and can retain a high remanence for a long time; the excitation coil 50 is located outside the permanent magnet 20, and can perform bidirectional magnetic field control by passing current; the permanent magnet 20 and the excitation coil 50 perform two-stage collaborative energy supply to the magnetosphere;

[0063] The elastic sleeve 30 is the connecting contact body of the variable stiffness connecting assembly and other components. When the magnetosphere is affected by the magnetic field, the magnetosphere changes its shape and acts on the elastic sleeve 30, and the elastic sleeve 30 expands outward or contracts due to its own elastic force.

[0064] The variable stiffness connection assembly provides a variable stiffness connection for two adjacent sections. In the initial state, under the action of the permanent magnet 20, the magnetosphere maintains a certain shape, and the elastic sleeve 30 is connected to the two adjacent sections in a sleeve manner; when the excitation coil 50 is energized and the excitation coil 50 generates a magnetic field in the same direction as the permanent magnet 20, the excitation coil 50 enhances the magnetic field generated by the permanent magnet 20, and the shape of the magnetosphere changes, which will increase the effect on the elastic sleeve 30, causing the elastic sleeve 30 to expand outward and perform a rigid connection; when the excitation coil 50 is energized and the excitation coil 50 generates a magnetic field in the opposite direction to the permanent magnet 20, the excitation coil 50 weakens the magnetic field generated by the permanent magnet 20, and the magnetosphere reduces the effect on the elastic sleeve 30, causing the elastic sleeve 30 to retract and perform a flexible connection, thereby achieving a variable stiffness connection, which is suitable for different use environments, avoiding problems such as holding back and getting stuck, or causing deformation at the connection position.

[0065] In some examples of the present invention, Figure 1 , Figure 2 As shown, the magnetorheological layer includes a magnetorheological fluid 42 and a magnetorheological elastomer 41 arranged in an annular shape;

[0066] Relative to the magnetorheological fluid 42 , the magnetorheological elastomer 41 is close to the center of the permanent magnet 20 ;

[0067] Specifically, the magnetorheological elastomer 41 and the magnetorheological fluid 42 are arranged from inside to outside;

[0068] The magnetorheological elastomer 41 can quickly respond to changes in the external magnetic field and change and adjust according to the magnitude of the magnetic field, that is, the elastic modulus of the magnetorheological elastomer 41 can change with the strength of the external magnetic field, and its mechanical properties can also change reversibly. When the magnetic field increases, the magnetorheological elastomer 41 itself changes shape and squeezes the magnetorheological fluid 42. When the magnetic field decreases, the magnetorheological elastomer 41 returns to a normal state.

[0069] The magnetorheological fluid 42 is a green, environmentally friendly, fluid material with controllable fluidity, which is non-toxic and pollution-free. When there is no magnetic field or a small magnetic field, the magnetorheological fluid 42 exhibits low-viscosity Newtonian fluid characteristics. When an external magnetic field or a large magnetic field is applied, the magnetorheological fluid 42 quickly changes into a high-viscosity, low-fluidity fluid, that is, under the influence of the external magnetic field, the magnetorheological fluid 42 itself can change from liquid to solid. The magnetorheological fluid 42 is enclosed in an annular cavity and can be statically sealed with an O-ring.

[0070] Under the action of the permanent magnet 20, the magnetorheological elastomer 41 and the magnetorheological fluid 42 are both in a certain shape, so that the elastic sleeve 30 has a certain rigidity. When the excitation coil 50 is energized to generate a magnetic field in the same direction as the permanent magnet 20, the magnetorheological elastomer 41 is deformed and increased to squeeze the magnetorheological fluid 42, and at the same time, the magnetorheological fluid 42 is converted into a solid state with high viscosity and low fluidity, so that the elastic sleeve 30 increases the contact with the connection position, that is, a rigid connection is performed; when the excitation coil 50 is energized to generate a magnetic field in the opposite direction to the permanent magnet 20, the magnetorheological elastomer 41 is deformed and retracted, and at the same time, the magnetorheological fluid 42 is converted into a liquid state with low viscosity, so that the elastic sleeve 30 reduces the contact with the connection position, that is, a flexible connection is performed;

[0071] In this example, a magnetorheological fluid 42 and a magnetorheological elastomer 41 are combined with each other and adjusted by a magnetic field. On the one hand, the magnetorheological elastomer 41 can effectively avoid the sedimentation and agglomeration of magnetic particles, thereby improving the stability and bearing strength of the connection. On the other hand, the magnetorheological fluid 42 is squeezed and changes between liquid and solid under the influence of the magnetic field, so that the elastic sleeve 30 can be adjusted between a rigid connection and a flexible connection. In addition, this flexible connection enables the two connected sections to rotate and move, and the degree of rigidity or flexibility of the connection can be controlled by the magnetic field.

[0072] In some examples of the present invention, Figure 1 , Figure 2 As shown, the excitation coils 50 are multiple groups; the multiple groups of excitation coils 50 are evenly spaced and distributed around the center of the permanent magnet 20;

[0073] Each excitation coil 50 is connected to a controller, and the controller independently controls the magnitude and direction of the current flowing into the excitation coil 50;

[0074] Specifically, the number of the excitation coils 50 is determined according to the actual use environment;

[0075] For example, when the number of the excitation coils 50 is eight, the eight excitation coils 50 are arranged around the center of the permanent magnet 20, and the wire of each excitation coil 50 is led out and can be connected to the controller separately;

[0076] In this example, the controller independently controls the corresponding excitation coils 50 to act, that is, the magnetic field generated by the permanent magnet is enhanced or weakened in the local area, and the state of the magnetosphere at the corresponding position changes, causing the elastic sleeve 30 to deform at the corresponding position. This example can be applied to different connection and installation environments. For example, when four adjacent excitation coils 50 generate a magnetic field in the same direction as the permanent magnet 20 and the other four adjacent excitation coils 50 generate a magnetic field in the opposite direction to the permanent magnet 20, the variable stiffness connection component can have a certain degree of automatic adjustable fluctuation at the connection position under the action of the rigid connection on one side, thereby avoiding manual operation.

[0077] In some examples of the present invention, Figure 1 As shown, a cavity is provided at the center of the support body 10 and one end of the cavity is sealed by a first cover plate 61;

[0078] The permanent magnet 20 and the excitation coil 50 are both accommodated in the cavity, and the center of the permanent magnet 20 is consistent with the center of the cavity;

[0079] The elastic sleeve 30 is connected to both sides of the support body 10 and forms a closed annular cavity through the sealing assembly 63;

[0080] Specifically, the support body 10 may be a T-shaped structure, and the central cavity is used to accommodate the permanent magnet 20 and the excitation coil 50; the annular cavity is sealed by a sealing component 63 to prevent the magnetorheological fluid 42 in liquid state from leaking;

[0081] In addition, both ends of the elastic sleeve 30 can be directly installed on both ends of the support body 10, or can be installed on one end of the support body 10 and one end of the first cover plate 61, which is determined according to the length structure of the support body 10 and the cavity. For example, when one end of the support body 10 exceeds the first cover plate 61, the elastic sleeve 30 is installed on the support body 10; when one end of the support body 10 does not exceed the first cover plate 61, the elastic sleeve 30 is installed on the first cover plate 61.

[0082] Further, the sealing assembly 63 may be a pair of sealing rings, one of which is close to the connection between the elastic sleeve 30 and the support body 10, and the other sealing ring is arranged between the peripheral side of the first cover plate 61 and the inner wall of the elastic sleeve 30, or between the peripheral side of the support body 10 and the inner wall of the elastic sleeve 30;

[0083] A pair of sealing rings, the inner wall of the elastic sleeve 30, and the peripheral side of the support body 10 form a closed annular cavity; it is noted that the sealing component 63 may also be other forms of sealing structures, not limited to sealing rings, that is, the sealing component 63 can prevent the magnetorheological fluid 42 from leaking from the annular cavity while meeting the use environment.

[0084] In some examples of the present invention, both ends of the elastic sleeve 30 are hard ring bodies;

[0085] Specifically, the two ends of the elastic sleeve 30 are hard bodies, which can be steel ring bodies, which are convenient for installing the elastic sleeve 30 on the end sides of the support body 10; the middle part of the elastic sleeve 30 is an elastic body, which is also the connection contact body between the variable stiffness connection component and other components, that is, the middle part of the elastic sleeve 30 is connected to the two adjacent sections in a sleeve manner; it is noted that when the variable stiffness connection component is connected to the other two sections, the hard ring bodies at both ends of the elastic sleeve 30 do not contact the connection position.

[0086] like Figure 3 , Figure 4 As shown, the tail connection device of the present invention comprises the above-mentioned variable stiffness connection assembly;

[0087] The variable stiffness connection assembly is sleeved into the positioning hole where the first belt rack 70 and the second belt rack 80 are connected;

[0088] Specifically, the tail of the self-moving machine at the excavation face in the coal mine is in a harsh and complex working environment;

[0089] As a main component of the tail connecting device, the variable stiffness connecting component can perform variable stiffness adjustment between the two belt racks.

[0090] In some examples of the present invention, the local tail connection device further includes a sensing component connected to the controller;

[0091] The sensing component is a displacement sensor, and the displacement sensor is configured to detect the height difference between the first belt frame 70 and the second belt frame 80;

[0092] When the height difference exceeds a certain range, the controller controls the excitation coil 50 to be energized to generate a magnetic field opposite to that of the permanent magnet 20;

[0093] or:

[0094] The sensing components are a plurality of pressure sheet sensors, which are arranged in the positioning holes where the variable stiffness connection assembly contacts the first belt frame 70 and the second belt frame 80, and are configured to detect the circumferential contact pressure of the positioning holes;

[0095] Multiple pressure plate sensors transmit pressure signals to the controller. When the pressure difference exceeds a certain range, the controller controls the current of the adjacent excitation coil 50 at the pressure plate sensor that detects a relatively large pressure, so that the excitation coil 50 generates a magnetic field opposite to the permanent magnet 20.

[0096] Specifically, under normal conditions, the first belt frame 70 and the second belt frame 80 need to be connected and maintained at the same level, that is, when the tail of the self-moving machine is in a good working condition of the bottom plate, there is no height difference between the connecting sections. At this time, the excitation coil 50 generates a magnetic field in the same direction as the permanent magnet 20, so that the first belt frame 70 and the second belt frame 80 are rigidly connected to each other;

[0097] When the displacement sensor detects the height difference between the first belt frame 70 and the second belt frame 80, it indicates that the tail of the self-moving machine is in a poor bottom plate condition, the lane is more undulating, and there is a height difference between the connecting sections. At this time, after receiving the signal, the controller controls the magnetic flux coil to generate a magnetic field opposite to the permanent magnet 20. The opposite magnetic field can make the connection position in a flexible and adjustable gap;

[0098] Alternatively, under normal conditions, the pressure sheet sensor detects the pressure at the contact position between the variable-rigidity connection component and the first belt frame 70 and the second belt frame 80. If the pressure deviation is small, it means that the connection position is evenly stressed and the tail of the self-moving machine is in a good working condition on the bottom plate; when the pressure difference reaches a certain range, it means that the connection position is unevenly stressed locally, that is, "holding force" or "stuck" occurs. At this time, the adjacent excitation coil 50 at the pressure sheet sensor with relatively large pressure is energized to generate a magnetic field opposite to the permanent magnet 20. The opposite magnetic field can make the connection position in a flexible and adjustable gap;

[0099] Take the example that there are eight excitation coils 50, which are sequentially Ⅰ-Ⅷ, and the induction component is a displacement sensor;

[0100] When the tail of the self-moving machine is in a harsh bottom plate condition and detects through the displacement sensor that the first belt frame 70 is higher than the second belt frame 80, the controller can control the excitation coil 50V-VIII near the first belt frame 70 to generate a magnetic field opposite to the permanent magnet 20 to weaken or offset the magnetic field of the permanent magnet 20, so that the connection position is flexibly connected near the first belt frame 70, and there is a certain rotation space to avoid mechanical damage; the excitation coil 50Ⅰ-Ⅳ near the second belt frame 80 generates a magnetic field in the same direction as the permanent magnet 20, so that the connection position is in a rigid state near the second belt frame 80, ensuring a certain degree of rigidity and stability of the connection position.

[0101] In some examples of the present invention, Figure 3 As shown, a tail connection device further includes a second cover plate 62;

[0102] The second cover plate 62 is mounted on the first cover plate 61 by bolts, and squeezes the first belt frame 70 and the second belt frame 80 to limit the axial position;

[0103] Specifically, the diameter of the second cover plate 62 is larger than the positioning holes connecting the first belt rack 70 and the second belt rack 80, and the first cover plate 61 can be installed on the first cover plate 61 by bolts. At this time, the second cover plate 62 can squeeze and limit the first belt rack 70 and the second belt rack 80 to prevent the first belt rack 70 and the second belt rack 80 from axial movement.

[0104] A method for using a tail connection device comprises the following steps:

[0105] S1, insert the variable stiffness connection assembly into the positioning hole where the first belt rack 70 and the second belt rack 80 are connected;

[0106] Initially, under the action of the permanent magnet 20, the magnetorheological elastomer 41 and the magnetorheological fluid 42 are in a certain state, so that the elastic sleeve 30 has a certain rigidity;

[0107] S2, when the tail of the self-moving machine is in a good working condition on the bottom plate, the variable stiffness connection component can provide a better rigid connection, and the multiple excitation coils 50 generate a magnetic field in the same direction as the permanent magnet 20, and the magnetorheological elastomer 41 deforms and increases to squeeze the magnetorheological fluid 42, and at the same time, the magnetorheological fluid 42 is converted into a high-viscosity, low-fluidity solid state, so that the elastic sleeve 30 increases the contact with the positioning hole, completing the rigid connection;

[0108] S3, when the tail of the self-moving machine is in a poor working condition of the bottom plate, the signal is transmitted to the controller through the induction component, and different excitation coils 50 are controlled respectively, so that some excitation coils 50 generate a magnetic field opposite to the permanent magnet 20, and the magnetorheological elastomer 41 at the corresponding circumferential position is deformed and retracted, and at the same time, the magnetorheological fluid 42 is converted into a low-viscosity liquid state, so that the circumferential position of the elastic sleeve 30 is reduced. The interaction with the positioning hole is reduced, and the stability of the rigid connection is guaranteed to a certain extent, and a certain degree of flexible adjustable gap is provided;

[0109] Alternatively, all the excitation coils 50 generate a magnetic field opposite to the permanent magnet 20 and form a reverse magnetic field in the magnetosphere, so that the elastic sleeve 30 as a whole reduces the interaction with the positioning hole, thereby completing a flexible connection.

[0110] The exemplary implementation scheme of the variable stiffness connection assembly proposed in the present invention is described in detail above with reference to the preferred embodiments. However, those skilled in the art will appreciate that, without departing from the concept of the present invention, various modifications and variations may be made to the above-mentioned specific embodiments, and various technical features and structures proposed in the present invention may be combined in various ways without exceeding the protection scope of the present invention, which is determined by the appended claims.

Claims

1. A variable stiffness connection assembly, characterized in that: include: A support body (10); A permanent magnet (20) is located inside and outside the support body (10) and is provided with an excitation coil (50) for passing current to generate a bidirectional magnetic field; An excitation coil (50) is arranged outside the permanent magnet (20) and is configured to generate a magnetic field in the same direction or in the opposite direction as the permanent magnet (20) by passing a current; An elastic sleeve (30) is sleeved on the outside of the support body (10) and forms a sealed annular cavity with the peripheral side of the support body (10); The magnetic fluid layer is located in the annular cavity and acts on the elastic sleeve (30) under the influence of the magnetic field, causing the elastic sleeve (30) to expand and retract.

2. The variable stiffness connection assembly according to claim 1, characterized in that: The magnetorheological layer comprises a magnetorheological fluid (42) and a magnetorheological elastomer (41) arranged in an annular shape; Relative to the magnetorheological fluid (42), the magnetorheological elastomer (41) is close to the center of the permanent magnet (20).

3. The variable stiffness connection assembly according to claim 2, characterized in that: The excitation coils (50) are in multiple groups; the multiple groups of excitation coils (50) are evenly spaced and distributed in the circumferential direction around the center of the permanent magnet (20); Each excitation coil (50) is connected to a controller, and the controller independently controls the magnitude and direction of the current flowing into the excitation coil (50).

4. The variable stiffness connection assembly according to any one of claims 1 to 3, characterized in that: A cavity is provided at the center of the support body (10), and one end of the cavity is sealed by a first cover plate (61); The permanent magnet (20) and the excitation coil (50) are both accommodated in the cavity, and the center of the permanent magnet (20) is consistent with the center of the cavity; The elastic sleeve (30) is connected to both sides of the support body (10) and forms a closed annular cavity through a sealing component (63).

5. The variable stiffness connection assembly according to claim 4, characterized in that: The sealing assembly (63) may be a pair of sealing rings; One sealing ring is close to the connection between the elastic sleeve (30) and the support body (10); the other sealing ring is arranged between the peripheral side of the first cover plate (61) and the inner wall of the elastic sleeve (30), or is installed between the peripheral side of the support body (10) and the inner wall of the elastic sleeve (30).

6. The variable stiffness connection assembly according to claim 4, characterized in that: Both ends of the elastic sleeve (30) are hard ring bodies.

7. A tail connection device, characterized in that: A variable stiffness connection assembly comprising the variable stiffness connection assembly of claim 3; The variable-rigidity connection assembly is sleeved into the positioning holes where the first belt rack (70) and the second belt rack (80) are butted.

8. The tail connection device according to claim 7, characterized in that: Also included is a sensing component connected to the controller; The sensing component is a displacement sensor, and the displacement sensor is configured to detect the height difference between the first belt frame (70) and the second belt frame (80); When the height difference exceeds a certain range, the controller controls the excitation coil (50) to be energized to generate a magnetic field opposite to that of the permanent magnet (20); or: The sensing components are a plurality of pressure sheet sensors, which are arranged in positioning holes where the variable-rigidity connection assembly contacts the first belt rack (70) and the second belt rack (80), and are configured to detect the circumferential contact pressure of the positioning holes; A plurality of pressure plate sensors transmit pressure signals to a controller. When the pressure difference exceeds a certain range, the controller controls the current of an adjacent excitation coil (50) at the pressure plate sensor that detects a relatively large pressure, so that the excitation coil (50) generates a magnetic field opposite to that of the permanent magnet (20).

9. The tail connection device according to claim 7, characterized in that: Also includes a second cover plate (62); The second cover plate (62) is mounted on the first cover plate (61) by means of bolts, and squeezes the first belt frame (70) and the second belt frame (80) to perform axial position limiting.

10. A method for using the tail connection device according to claim 8, characterized in that: The specific steps include: S1, inserting the variable stiffness connection assembly described in claim 3 into the positioning holes where the first belt rack (70) and the second belt rack (80) are connected; Initially, under the action of the permanent magnet (20), the magnetorheological elastomer (41) and the magnetorheological fluid (42) are both in a certain state, so that the elastic sleeve (30) has a certain rigidity; S2, when the tail of the self-moving machine is in a good working condition on the bottom plate, the variable stiffness connection component can provide a better rigid connection, the multiple excitation coils (50) generate a magnetic field in the same direction as the permanent magnet (20), the magnetorheological elastomer (41) deforms and increases to squeeze the magnetorheological fluid (42), and at the same time the magnetorheological fluid (42) is converted into a high-viscosity, low-fluidity solid state, so that the elastic sleeve (30) increases the contact with the positioning hole, completing the rigid connection; S3, when the tail of the self-moving machine is in a poor bottom plate working condition, the signal is transmitted to the controller through the induction component, and different excitation coils (50) are controlled respectively, so that some of the excitation coils (50) generate a magnetic field opposite to the permanent magnet (20), and the magnetorheological elastomer (41) at the corresponding circumferential position is deformed and retracted, and at the same time, the magnetorheological fluid (42) is converted into a low-viscosity liquid state, so that the circumferential position of the elastic sleeve (30) is reduced. The interaction with the positioning hole is ensured to a certain extent, and the stability of the rigid connection is guaranteed and a certain degree of flexible adjustable gap is provided; Alternatively, all the excitation coils (50) generate a magnetic field in the opposite direction to the permanent magnet (20) and form a reverse magnetic field in the magnetosphere, so that the elastic sleeve (30) as a whole reduces the interaction with the positioning hole, thereby completing a flexible connection.

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