A pulley friction braking type linear motor catapult

Abstract

The present invention belongs to the technical field of linear motors, and particularly relates to a trolley friction braking type linear motor ejector. The present invention provides a new solution for the additional braking of the trolley of the linear motor ejector, and through direct transplantation, adaptive improvement or further innovation, it can be generally applicable to the deceleration braking of the driving slider in various types of linear ejectors; by adjusting the thickness of the gasket group, the pre-tightening force of the disc spring group in the deceleration module can be adjusted, so that different frictional forces can be output during operation, and the adaptation range is wide; the present invention adopts a modular combination method, and by changing the number of deceleration modules, the longitudinal installation positions of each deceleration module, and the setting of the pre-tightening force of the annular elastic member of each deceleration module, various braking combinations with different deceleration characteristic curves can be formed to meet the diverse working condition requirements.

Description

Technical Field

[0001] The present invention belongs to the technical field of linear motors, and particularly relates to a linear motor ejector with a friction brake for a trolley. Background Art

[0002] A linear motor generally consists of a primary (stator), a secondary (rotor), a frame, a trolley, and guide rails, etc. For a bilateral or parallel linear motor with a long primary and a short secondary, the frame is formed by connecting a pair of side walls and a base. The inner surfaces of the two side walls and the upper surface of the base form a U-shaped installation space; the primary coil module is longitudinally arranged on the inner surfaces of the two side walls along the frame; the secondary module is installed on the trolley; there are two pairs of upper and lower guide rails, both of which are symmetrically arranged left and right longitudinally along the frame. The two upper guide rails are installed on the tops of the two side walls, and the openings of the "C"-shaped cross-section rail grooves face each other. The two lower guide rails are installed at the bottoms of the inner surfaces of the side walls, and each has only a lateral positioning rail surface; the two rollers or sliders on both sides above the trolley are inserted into the rail grooves of the two upper guide rails with lateral and vertical clearance fits, and the two rollers or sliders on both sides below are inserted into the space between the rail surfaces of the two lower guide rails with lateral clearance fits; due to the constraints of the two pairs of upper and lower guide rails, the trolley can only slide back and forth longitudinally between the primary and the secondary under the electromagnetic force. During this process, the magnetic gap between the primary and the secondary always remains the same, and the distance between the bottom surface of the trolley and the upper surface of the frame base always remains the same. The trolley drives the load through an adapter or directly to generate the required linear motion when the motor works.

[0003] When the linear motor is used as an electromagnetic ejector, it is necessary to solve the problem of decelerating and braking the high-speed trolley after the ejected object reaches the set speed. Currently, the main technical method is reverse electromagnetic braking. Its advantage is that no additional structural components need to be added, but a certain length of braking section needs to be reserved on the frame and the guide rails, and the same primary coil module needs to be configured on the braking section of the frame. However, in engineering practice, due to specific application environment limitations, especially the vehicle space limitations when used as a weapon launch device, the ejector needs to have a more compact structure. Engineering usually adopts additional braking methods to compress the length of the braking section, thereby reducing the total length of the entire ejector. The currently used additional braking methods mainly include eddy current braking and forced braking with an end collision damper. Among them, eddy current braking requires installing corresponding induction metal plates and induction permanent magnets on the frame and the trolley, which complicates the motor structure, and the increase in the mass of the trolley (rotor) also results in a decrease in the net output thrust. If the secondary thrust magnet is used as the induction permanent magnet, the installation positions of the induction plate and the primary coil module conflict, and the trolley cannot be braked simultaneously; while the forced braking with an end collision damper cannot provide a safe and stable impact overload for secondary trolleys with different ejection speeds. Summary of the Invention

[0004] The technical problem to be solved by the present invention is that when the ejector uses the secondary thrust magnet as the induction permanent magnet, the installation positions of the induction plate and the primary coil module conflict, and it is impossible to brake the trolley at the same time; while the forced braking of the end collision damper cannot provide a safe and stable impact overload for secondary trolleys with different ejection speeds. To solve the above problems, the present invention provides a trolley friction braking type linear motor ejector.

[0005] The purpose of the present invention is achieved in the following way: A trolley friction braking type linear motor ejector includes a primary coil module, a secondary module, a frame, a trolley, a guide rail, and a friction braking component. The frame includes a side wall and a base. The inner surface of the side wall of the frame and the upper surface of the base of the frame form a groove-shaped installation space. The primary coil module is longitudinally arranged on the inner surfaces of the two side walls along the frame. The secondary module is arranged on the trolley. There is at least one pair of guide rails. Each pair of guide rails is arranged on the frame, and each pair of guide rails is symmetrically arranged longitudinally along the frame. The trolley is located in the groove of the frame, and the trolley is supported and constrained by the guide rails. The trolley can move longitudinally along the groove of the frame. The friction braking component is longitudinally arranged in the deceleration section of the frame, and the friction braking component is vertically arranged between the upper surface of the base of the frame and the lower bottom surface of the trolley. The friction braking component includes a substrate and at least one deceleration module. The substrate is strip-shaped and is longitudinally arranged on the base along the frame. The deceleration module includes a friction block. The friction block is arranged above the substrate, and the friction block is elastically connected to the substrate vertically. In the natural state, the upper surface of the friction block is higher than the lower bottom surface of the trolley. In the compressed state, the upper surface of the friction block is not higher than the lower bottom surface of the trolley.

[0006] At least one group of connection holes is provided on the substrate. The deceleration module further includes two nail columns and two annular elastic members. Chamfers are provided above the front and rear ends of the friction block. Two through holes are longitudinally arranged on the friction block, and upper counterbores and lower counterbores are respectively arranged on the end faces of the through holes. The nail column includes a head, a body, and a tail. The outer diameters of the head, the body, and the tail of the nail column increase in sequence to form a stepped shaft. The maximum deformation amount of the annular elastic member is H. The heads and the bodies of the two nail columns sequentially pass through the two through holes of the friction block and the two annular elastic members. The head is embedded in the connection hole of the substrate and forms a mechanical connection between the head and the substrate. The body is in clearance fit with the through hole of the friction block and the inner hole of the annular elastic member respectively. The tail of the nail column is located in the upper counterbore of the friction block. The annular elastic member is located between the upper surface of the substrate and the bottom surface of the lower counterbore of the friction block. When the friction block is not under pressure, there is a gap d between the lower surface of the friction block and the upper surface of the substrate. The distance D1 from the upper surface of the friction block to the upper surface of the substrate is greater than the maximum distance D2 from the lower bottom surface of the trolley to the upper surface of the substrate, and there is d≥D1 - D2 and H≥D1 - D2. When the friction block is under pressure, the upper surface of the tail of the nail column is always not higher than the upper surface of the friction block.

[0007] At least two groups of connection holes are longitudinally opened on the upper surface of the substrate. There are at least two deceleration modules. The deceleration modules are longitudinally arranged on the substrate, and the deceleration modules are arranged on the substrate through the corresponding connection holes of the substrate.

[0008] The annular elastic member is a disc spring group formed by stacking two disc springs of the same specification.

[0009] The friction block is made of a composite material with a large coefficient of friction.

[0010] The deceleration module further includes two gasket groups. Each gasket group includes at least one gasket. The gasket groups are loosely sleeved on the stud posts. The gasket groups are longitudinally located between the annular elastic member and the bottom surface of the sunken hole of the friction block.

[0011] The head of the stud post is an external thread section, and the connection holes on the substrate are threaded holes of the same specification. The head of the stud post is embedded in the connection holes of the substrate to form a threaded connection therewith.

[0012] The head of the stud post is a cylindrical section, and the connection holes on the substrate are cylindrical holes. The head of the stud post is embedded in the connection holes of the substrate and the head of the stud post forms an interference fit connection with the substrate.

[0013] The guide rail includes an upper guide rail and a lower guide rail. There are two upper guide rails and two lower guide rails respectively. The "C"-shaped cross-section rail grooves of the two upper guide rails or the two lower guide rails face each other. The two upper guide rails are arranged at the tops of the two side walls, and the two lower guide rails are arranged at the bottoms of the inner surfaces of the two side walls. The trolley includes lower horizontal rollers, upper horizontal rollers and upper vertical rollers. The upper vertical rollers and upper horizontal rollers arranged on both sides above the trolley are in clearance fit and are embedded in the rail grooves of the two upper guide rails. The lower horizontal rollers on both sides below the trolley are in clearance fit and are embedded between the rail surfaces of the two lower guide rails.

[0014] When in use of the present invention, when the trolley slides at high speed above the present invention, the front end of the bottom of the trolley contacts the front chamfered slope of the friction block of the deceleration module and then continues to move forward, thereby pressing the friction block downward. During this process, the trolley will also move slightly upward under the action of the reaction force of the friction block to eliminate the fit clearance between its rollers or sliders and the upper rail surface of the corresponding guide rail. After the front end of the bottom of the trolley crosses the front slope of the friction block, the lower bottom surface of the trolley fits with the upper surface of the friction block, and the friction block is pressed to the lowest position. After that, when the rear end of the bottom of the trolley crosses the rear slope of the friction block, the friction block starts to bounce until it returns to its original highest position. From the moment the friction block of a deceleration module is pressed downward by the bottom of the trolley until it completely bounces up after the bottom of the trolley moves away, the annular elastic member thereof is deformed by the compression of the friction block, and most of its spring force is converted into the normal pressure between the upper surface of the friction block and the lower bottom surface of the trolley, and then into the sliding friction force between the two, so as to brake the moving trolley. When multiple deceleration modules are arranged continuously, the bottom of the trolley can press down multiple friction blocks at the same time, and the braking effect is more remarkable.

[0015] The beneficial effects of the present invention are as follows:

[0016] a) The present invention provides a new solution for the additional braking of the slider of a linear motor catapult, and through direct transplantation, adaptive improvement or further innovation, it can be generally applied to the deceleration braking of the driving slider in various types of linear catapults;

[0017] b) By adjusting the thickness of the gasket group, the pre-tightening force of the disc spring group in the deceleration module can be adjusted, so that different frictional forces can be output during operation, and the adaptation range is wide;

[0018] c) The present invention adopts a modular combination method. By changing the number of deceleration modules, the longitudinal installation positions of each deceleration module, and the setting of the pre-tightening force of the annular elastic members of each deceleration module, various braking combinations with different deceleration characteristic curves can be formed to meet the diverse working condition requirements;

[0019] d) When the total length of the bottom of the slider is much greater than the length of the friction block and the deceleration modules are arranged continuously, the frictional braking force received by the slider experiences a gradual increase from zero to a stable value and then remains stable. The braking process is both stable and efficient. Description of the Drawings

[0020] Figure 1 It is a three-dimensional installation layout diagram of a partial section of a slider friction braking type linear motor catapult (hiding one side wall and guide rail of the catapult, etc.).

[0021] Figure 2 It is a longitudinal mid-sectional view of the friction braking component deceleration module of a slider friction braking type linear motor catapult.

[0022] Figure 3 It is a partial longitudinal mid-sectional view of the friction block of the friction braking component of a slider friction braking type linear motor catapult.

[0023] Figure 4 It is a schematic diagram of the friction braking component of a slider friction braking type linear motor catapult implementing deceleration braking on the slider (hiding the side wall, guide rail and lower rollers of the slider, etc.).

[0024] Among them, 1 - base; 2 - lower guide rail; 3 - side wall; 4 - primary coil module; 5 - upper guide rail; 6 - secondary thrust magnet group module; 7 - slider; 8 - substrate; 9 - deceleration module; 71 - lower bottom surface of the slider; 72 - bottom of the slider; 73 - lower horizontal roller; 74 - upper horizontal roller; 75 - upper vertical roller; 81 - threaded connection hole; 91 - friction block; 92 - stud; 93 - disc spring group; 94 - gasket group; 911 - chamfer; 912 - through hole; 913 - upper counterbore; 914 - lower counterbore; 921 - threaded stud head; 922 - stud body; 923 - stud tail. Detailed Description of the Invention

[0025] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0026] To make the objectives, 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 with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are only a part rather than all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0027] Therefore, the detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0028] It should be noted that like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not require further definition and explanation in subsequent drawings.

[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0030] In the present invention, unless otherwise clearly defined and limited, the terms "mounted", "connected", "coupled", "fixed", etc. shall be construed broadly. For example, it may be a fixed connection, a detachable connection, or an integral body; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0032] Embodiment 1:

[0033] As shown in the appended Figure 1 to the appended Figure 4 figures, a pulley friction braking type linear motor ejector is composed of a primary coil module 4, a secondary thrust magnet group module 6, a frame, a pulley 7, an upper guide rail 5, a lower guide rail 2 and a friction braking assembly, etc.; wherein: the frame is formed by connecting a pair of side walls 3 and a base 1, and a groove-shaped installation space is formed on the inner surfaces of the two side walls 3 and the upper surface of the base 1; the primary coil module 4 is longitudinally arranged on the inner surfaces of the two side walls 3 along the frame; the secondary thrust magnet group 6 is installed on the pulley 7; there is one pair each of the upper guide rail 5 and the lower guide rail 2, and they are both symmetrically arranged left and right longitudinally along the frame. The two upper guide rails 5 are installed on the tops of the two side walls 3, and the "C"-shaped cross-section rail grooves thereof face each other. The two lower guide rails 2 are installed at the bottoms of the inner surfaces of the two side walls 3, and each has only a lateral positioning rail surface; the pulley includes two pairs each of upper vertical rollers 75, upper horizontal rollers 74 and lower horizontal rollers 73. The upper vertical rollers 75 and upper horizontal rollers 74 on both sides above the pulley 7 are fitted into the rail grooves of the two upper guide rails 5 with vertical and lateral clearances, and the lower horizontal rollers 73 on both sides below the pulley 7 are fitted into the rail surfaces between the two lower guide rails 2 with lateral clearances; due to the constraints of the upper and lower pairs of guide rails, the pulley 7 can only slide back and forth longitudinally along the motor under the electromagnetic force between the primary coil module 4 and the secondary thrust magnet group 6. During this process, the magnetic gap between the primary coil module 4 and the secondary thrust magnet group 6 always remains consistent, and the distance between the lower bottom surface 71 of the pulley and the upper surface of the frame base 1 always remains consistent. The pulley 7 can push a load through an adapter. When the motor works, the pulley 7 drives the load to generate the required linear motion.

[0034] The friction braking assembly includes a substrate 8 and a plurality of deceleration modules 9, which are installed between the upper surface of the base 1 of the linear ejector frame and the lower bottom surface 71 of the pulley. All the deceleration modules 9 are arranged in a row and installed on the substrate 8, and the deceleration modules 9 are continuously arranged longitudinally along the substrate 8.

[0035] The substrate 8 is strip-shaped and is longitudinally arranged under the pulley 7 along the frame. The lower surface of the substrate 8 is fixedly connected to the upper surface of the base 1 of the frame, and a series of threaded connection holes 81 are longitudinally formed on the upper surface of the substrate 8.

[0036] The deceleration module 9 includes a friction block 91, two stud posts 92, two disc spring groups 93 and two gasket groups 94. The friction block 91 is a longitudinally and transversely symmetric member made of a composite material with a large friction coefficient. Chamfers 911 are provided above the front and rear ends thereof, and two through holes 912 are longitudinally formed. Upper counterbores 913 and lower counterbores 914 are respectively provided on the end faces of the two through holes 912. The stud post 92 includes a threaded head 921, a column body 922 and a column tail 923. The outer diameters of the threaded head 921, the column body 922 and the column tail 923 increase in sequence to form a stepped shaft. Each disc spring group 93 contains two disc springs of the same specification, and their combination form is superposition. The maximum deformation amount of the disc spring group 93 is H. Each gasket group contains 1 - 2 gaskets with the same inner and outer diameters but different thicknesses. The heads and the column bodies of the two stud posts 92 sequentially pass through the two through holes 912 of the friction block 91, the two disc spring groups 93 and the gasket group 94, and the threaded head 921 is screwed into the threaded connection hole 81 of the substrate 8 to form a threaded connection therewith. The column body 922 has a large clearance fit with the through hole 912 of the friction block 91, the inner holes of the disc spring group 93 and the gasket group 94. The column tail 923 is located in the upper counterbore 913 of the friction block 91. Longitudinally, the disc spring group 93 is supported between the upper surface of the substrate 8 and the gasket group 94, and the gasket group 94 is located between the disc spring group 93 and the bottom surface of the lower counterbore 914 of the friction block 91. When the friction block 91 is not under pressure, there is a gap d between the lower surface of the friction block 91 and the upper surface of the substrate 8, and the distance D1 from its upper surface to the upper surface of the substrate 8 is greater than the maximum distance D2 from the lower bottom surface 71 of the pulley to the upper surface of the substrate 8, and d≥H≥D1 - D2. When the friction block 91 is under pressure, the upper surface of the column tail 923 of the stud post 92 is always not higher than the upper surface of the friction block 91.

[0037] In the present invention, the substrate 8 can also be integrated with the base 1 of the linear ejector frame to become the middle convex part of the base 1.

[0038] In another embodiment of the present invention, the head of the stud post 92 in the deceleration module 9 is a cylindrical section, and the connection hole on the substrate 8 is a cylindrical hole. The head is embedded in the substrate connection hole to form an interference fit connection of hole and shaft. This method facilitates the disassembly, assembly and flexible arrangement of the deceleration module 9 on the substrate 8.

[0039] The working process of the trolley brake in the present invention is as follows: When the trolley 7 slides at high speed above the first deceleration module 9, the chamfered edge at the front end of the bottom 71 of the trolley contacts the inclined surface of the front chamfer 911 of the friction block 91 of the deceleration module 9. As the trolley 7 continues to move forward, the friction block 91 begins to be pressed down. At the same time, the trolley 7 will also move slightly upward under the reaction force of the friction block 91 to eliminate the fitting clearance between its upper vertical roller 75 and the upper rail surface of the corresponding guide rail. After the front end of the bottom 72 of the trolley crosses the inclined surface of the front chamfer 911 of the friction block 91, the lower bottom surface 71 of the trolley fits with the upper surface of the friction block 91, and the friction block 91 is pressed to the lowest position. After that, when the rear end of the bottom 72 of the trolley crosses the chamfered inclined surface at the rear end of the friction block 91, the friction block 91 begins to bounce back until it returns to its original highest position. From the moment the friction block 91 of a deceleration module 9 is pressed down by the bottom 72 of the trolley until it completely bounces back after the bottom 72 of the trolley moves away, the disc spring group 93 of it is deformed by the compression of the friction block, and most of its spring force is converted into the normal pressure between the upper surface of the friction block 91 and the lower bottom surface 71 of the trolley, and then into the sliding friction force between the two, so as to brake the moving trolley. Since the deceleration modules 9 are arranged continuously and the total length of the bottom 72 of the trolley is much greater than the length of a single friction block 91, starting from when the trolley 7 runs above the first deceleration module 9, the number of friction blocks 91 pressed down by it accumulates to a fixed value in sequence and then remains unchanged until its speed is reduced to zero. During this process, the frictional braking force received by the trolley 7 experiences a process of gradually increasing from zero to a stable value and then remaining stable, and the braking process is both stable and efficient.

[0040] The trolley braking solution proposed by the present invention can also be used for the deceleration braking of the sliding body driven in other linear catapults through direct transplantation or adaptive improvement.

[0041] The present invention is not limited to the above various specific embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can form other specific refinement solutions by further specifying or using conventional equivalent substitutions in accordance with the present invention, such as replacing the annular elastic member with a helical compression spring, an annular spring combination or a diaphragm spring combination, or changing the combination method of the disc springs to an opposed and composite method, and so on. However, as long as the implementation mode substantially adopts all the technical features of the technical solution of the present invention, it is within the protection scope of the claims of the present invention.

Claims

1. A pulley friction braking type linear motor catapult, comprising a primary module, a secondary module, a frame, a pulley, a guide rail and a friction braking assembly, characterized in that: The frame includes side walls and a base. A groove-shaped mounting space is formed by the inner surface of the frame side walls and the upper surface of the frame base. The primary modules are arranged longitudinally along the frame on the inner surfaces of the two side walls. The secondary module is arranged on a trolley. There is at least one pair of guide rails. Each pair of guide rails is arranged on the frame and symmetrically arranged longitudinally along the frame. The trolley is located in the frame groove and is supported and constrained by the guide rails. The trolley can move longitudinally along the frame groove. The friction braking assembly is arranged longitudinally on the deceleration section of the frame and vertically between the upper surface of the frame base and the lower bottom surface of the trolley. The friction braking assembly includes a base plate and at least one deceleration module. The base plate is strip-shaped and arranged longitudinally on the base along the frame. The deceleration module includes a friction block. The friction block is arranged above the base plate and elastically connected to the base plate vertically. In the natural state, the upper surface of the friction block is higher than the lower bottom surface of the trolley. In the compressed state, the upper surface of the friction block is not higher than the lower bottom surface of the trolley.

2. The linear motor catapult with pulley friction braking according to claim 1, characterized in that: At least one set of connection holes is provided on the base plate. The deceleration module further includes two stud posts and two annular elastic members. Chamfers are provided above the front and rear ends of the friction block. Two through holes are arranged longitudinally on the friction block, and upper counterbores and lower counterbores are respectively arranged on the end faces of the through holes. The stud post includes a head, a body, and a tail. The outer diameters of the head, the body, and the tail of the stud post increase in sequence to form a stepped shaft. The maximum deformation amount of the annular elastic member is H. The heads and the bodies of the two stud posts pass through the two through holes of the friction block and the two annular elastic members in sequence. The head is embedded in the connection hole of the base plate and forms a mechanical connection with the base plate. The body is in clearance fit with the through hole of the friction block and the inner hole of the annular elastic member respectively. The tail of the stud post is located in the upper counterbore of the friction block. The annular elastic member is located between the upper surface of the base plate and the bottom surface of the lower counterbore of the friction block. When the friction block is not under pressure, a gap d is maintained between the lower surface of the friction block and the upper surface of the base plate. The distance D1 from the upper surface of the friction block to the upper surface of the base plate is greater than the maximum distance D2 from the lower bottom surface of the trolley to the upper surface of the base plate, and d≥D1 - D2 and H≥D1 - D2. When the friction block is under pressure, the upper surface of the tail of the stud post is always not higher than the upper surface of the friction block.

3. The linear motor catapult with a pulley friction brake according to claim 1 or 2, characterized in that: At least two sets of connection holes are longitudinally formed on the upper surface of the base plate. There are at least two deceleration modules. The deceleration modules are arranged longitudinally along the base plate and are arranged on the base plate through the corresponding connection holes of the base plate.

4. The linear motor catapult with pulley friction braking according to claim 2, characterized in that: The annular elastic member is a disc spring group formed by stacking two disc springs of the same specification.

5. The linear motor catapult with pulley friction braking according to claim 1, wherein: The friction block is made of a composite material with a large friction coefficient.

6. The linear motor catapult with pulley friction braking according to claim 2, characterized in that: The deceleration module further includes two gasket groups. Each gasket group includes at least one gasket. The gasket groups are loosely sleeved on the stud posts and are longitudinally located between the annular elastic member and the bottom surface of the lower counterbore of the friction block.

7. A pulley friction braking type linear motor catapult according to claim 2, characterized in that: The head of the stud post is an external thread section, and the connection holes on the base plate are thread holes of the same specification. The head is embedded in the connection hole of the base plate and forms a threaded connection with it.

8. A pulley friction braking type linear motor ejector according to claim 2, characterized in that: The head of the stud post is a cylindrical section, and the connection holes on the base plate are cylindrical holes. The head is embedded in the connection hole of the base plate and forms an interference fit connection between the hole and the shaft with the base plate.

9. The linear motor catapult with pulley friction braking according to claim 1, wherein: The guide rails include upper guide rails and lower guide rails, with two of each. The "C"-shaped cross-section rail grooves of the two upper guide rails or the two lower guide rails face each other. The two upper guide rails are arranged at the tops of the two side walls, and the two lower guide rails are arranged at the bottoms of the inner surfaces of the two side walls. The trolley includes lower horizontal rollers, upper horizontal rollers and upper vertical rollers. The upper vertical rollers and upper horizontal rollers arranged on both sides above the trolley are fitted into the rail grooves of the two upper guide rails with a clearance fit, and the lower horizontal rollers on both sides below the trolley are fitted into the rail surfaces between the two lower guide rails with a clearance fit.

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