202results about How to "Good anti-loose effect" patented technology

The invention provides a rapid anti-loosening fastening device and an assembling and using method thereof, and belongs to the field of mechanical fastening devices. The rapid anti-loosening fastening device and the assembling and using method thereof solve the problem that an existing thread fastening device is low in disassembling and assembling efficiency. The rapid anti-loosening fastening device comprises a fastening bolt and a fastening nut, wherein the fastening bolt comprises a bolt rod and a bolt head, the rod wall of the bolt rod is provided with a thread groove, a one-way tooth groove is formed in the groove bottom of the thread groove, the fastening nut comprises a thread sleeve, a baffle ring is fixed on the outer wall of the bottom end of the thread sleeve, the rapid anti-loosening fastening device further comprises an inner adjusting sleeve which sleeves the outer wall of the thread sleeve and an outer adjusting sleeve which sleeves the outer wall of the inner adjusting sleeve and the outer wall of the baffle ring, an adjusting groove is formed in the inner wall of the inner adjusting sleeve, an adjusting hole is formed in the sleeve wall of the thread sleeve, the rapid anti-loosening fastening device further comprises an adjusting rod and an adjusting pipe which sleeves the adjusting rod, the adjusting pipe is arranged in the adjusting hole in a penetrating mode, the outer end of the adjusting pipe is fixedly provided with an adjusting block which is located in the adjusting groove in a sliding mode, and a baffle pipe is fixed on the hole wall of the inner end of the adjusting hole. According to the fastening device, a structure similar to the thread fit can be realized so that fixation at any degree can be realized, moreover, disassembling and assembling are efficient, and the anti-loosening effect can be realized.

The invention relates to a connecting structure capable of being rapidly mounted and dismounted. The connecting structure comprises a locking pin and a locking block. The locking pin comprises a pin shaft and a pin shaft sleeve arranged on the lower portion of the pin shaft in a sleeving mode through threads. The bottom surface of the pin shaft is a conical surface. The lower portion, under the pin shaft, of the pin shaft sleeve is provided with a plurality of through holes evenly distributed around the axis, and a steel ball which can freely move but can not fall out is arranged in each through hole. The locking block is provided with a connecting hole and a containing cavity, the connecting hole is formed in the top surface of the locking block, and the bottom of the connecting hole is communicated with the top of the containing cavity, and the top surface of the containing cavity is a conical surface. In the installation process, the pin shaft sleeve and the locking block are fixed to a connector and a connected part respectively, the pin shaft sleeve penetrates through the connector and enters the containing cavity of the locking block through the connecting hole, the pin shaft is rotated downwards so that the steel balls can be pushed to squeeze the conical top surface of the containing cavity through the conical bottom surface of the pin shaft, and the connector and the connected part squeeze and fix each other when subjected to force in opposite directions. In the dismounting process, the pin shaft is rotated upwards, the steel balls are not subjected to force, and then the connector and the connected part are separated.

The invention provides a stable lock bolt, and belongs to the field of mechanical fasteners. The stable lock bolt solves the problem that an existing bolt is poor in loosening preventing effect. The stable lock bolt comprises a bolt head and a bolt rod, wherein the bolt head is in a round head shape, and a pressing hole is formed in the bolt head and the bolt rod. A pressing rod penetrating through the pressing hole is further included. An adjusting cap is further included and comprises an adjusting plate fixed to the top end of the pressing rod and an adjusting sleeve fixed to the outer edgeof the adjusting plate, wherein the adjusting sleeve sleeves the bolt head, and a pressing block is fixed to the bottom end of the pressing rod. An expansion gasket sleeving the pressing rod is further included. The hole wall of the pressing hole is provided with a limiting groove. The rod wall of the pressing rod is provided with a limiting block which is located in the limiting groove in a sliding manner. The distance between the middle portion of the limiting groove and the top end of the pressing hole is smaller than the distance between the two ends of the limiting groove and the bottom end of the pressing hole, the distance between the front end of the limiting groove and the top end of the pressing hole is larger than the distance between the rear end of the limiting groove and thetop end of the pressing hole, smooth transition is achieved from the middle portion of the limiting groove to the two ends of the limiting groove, and an elastic reset mechanism is arranged between the pressing rod and the bolt rod. The bolt is better in loosening preventing effect.

The invention relates to the field of sealing parts, in particular to a waterproof-sealing electrical connector assembly. The waterproof-sealing electrical connector assembly comprises a plug and a socket; a sealing rubber ring arranged on a plug shell comprises a radial sealing part and an end face sealing part which are formed in the front and at the back; the radial sealing part and the end face sealing part form a step shaft sleeve structure; one side, which is close to the radial sealing part, of the end face sealing part forms a step face facing the front together with the radial sealing part; the step face is provided with a sealing face for being in seal fit with the front end face of a socket shell; a sealing face for being attached and sealed with a sealing retaining edge is formed on the rear lateral surface of the end face sealing part; a sealing convex rib for being in seal fit with the inner wall surface of the socket shell is arranged on the outer peripheral surface of the radial sealing part; the sealing convex rib is connected end to end around the axis of the radial sealing part to form a closed loop. The electrical connector assembly solves the problem of poor waterproof-sealing performance of an existing electrical connector assembly.

The invention provides a rapid self-locking type nut structure and an assembly and application method thereof, and belongs to the field of machine parts. The rapid self-locking type nut structure andthe assembly and application method thereof solve the problems that an existing nut is troublesome to assemble and disassemble and poor in anti-loose effect. The rapid self-locking type nut structurecomprises a nut sleeve, also comprises a sleeve-shaped locking sleeve, and further comprises a plurality of arc-shaped main nut sheets and auxiliary nut sheets, wherein the sleeve-shaped locking sleeve sleeves an outer locking groove in a matched mode, and the main nut sheets and the auxiliary nut sheets are located in the inner locking groove; the outer wall of the nut sleeve is in a regular hexagon shape; the inner wall of the nut sleeve is in a circular sleeve shape; the outer locking groove is formed in the outer wall, close to the top end, of the nut sleeve; the sleeve-shaped inner locking groove is coaxially formed in the middle of the inner wall of the nut sleeve; the outer wall of the locking sleeve is in a regular hexagon shape which is the same as that of the outer wall of the nut sleeve; inner threads are arranged on the inner arc surfaces of the main nut sheets and the auxiliary nut sheets; a main displacement mechanism is arranged between each main nut sheet and the locking sleeve; and an auxiliary displacement mechanism is arranged between each auxiliary nut sheet and the locking sleeve. The nut structure can be quickly disassembled and assembled, and meanwhile, the anti-loose effect is better.

The present invention belongs to the technical field of laser machining equipment, and particularly relates to a laser cutting head follow-up device. The laser cutting head follow-up device comprises a stepping motor, a coupling, a bearing seat I, a shaft end support I, a rolling bearing I, a nut seat, a ball screw nut, a ball screw, a rolling bearing II, a shaft end support II, a bearing seat II, a sleeve and a nozzle. The laser cutting head follow-up device has the advantages that a guide rail is reduced, the ball screw simultaneously has the effects of transmission and guiding, a half-arc groove milled on the excircle of the nut is matched with a cylindrical pin and has good anti-loose effect, capacitive sensing is adopted, the rotation of the stepping motor is controlled through electric signals, the distance between the laser nozzle and the surface of a cut work piece can be automatically adjusted, automatic focusing is always performed, work pieces are artistic, uniformly cut and formed, and have no burrs, and the cutting quality and the cutting efficiency are greatly improved.

The invention belongs to metallurgical equipment fasteners, and particularly relates to a novel locking fastener applicable to a straightener system. The novel locking fastener at least comprises a screw rod (1) and a nut (3), and is characterized in that when the screw rod (1) and the nut (3) are screwed together, the bottom end of the nut (3) is fixedly connected with a pressure cover (5) through a locking screw (6), and the head of the pressure cover (5) is screwed in the screw rod (1) in a threaded way. The novel locking fastener has the advantages of being good in locking effect and easy to process and implement, and ensuring that a user can easily observe whether the thread is loosened.

The invention discloses a gas extraction device in a coal mining area. By setting a high frequency oscillator, the gas can be completely extracted and the gas flow can be promoted. In the process of gas extraction, a plugging assembly is firstly used to mount and position an extraction pipe and after well plugging, good sealing performance is ensured; later, an extraction pump is used, a control valve is controlled, the gas is firstly extracted, after the gas is extracted to a certain degree at an extraction hole, the high frequency oscillator is used to oscillate, and after a certain period of continuous extraction, a pulse aeration module is opened again, a protective gas is impulsively injected into a coal seam, after certain pressure arrives in the borehole in a certain time of pulse aeration, the gas in the borehole is continuously extracted, and thus, the high frequency oscillator is used to promote circulation of the gas, the extraction effects are ensured, the remaining small part of gas is subjected to exchange and circulation by using a pulse aeration mode, and the gas is completely extracted.

The invention discloses a double-rod bolt. The double-rod bolt comprises an outer bolt and an inner bolt. The outer bolt comprises an outer bolt head which is of an integrated structure and an outer bolt rod which is provided with an outer thread extending to the tail end. The outer bolt is axially provided with a through axle hole penetrating the outer bolt head and the outer bolt rod. The innerbolt comprises an inner bolt head and an inner bolt rod. The diameter of the inner bolt head is larger than the diameter of the through axle hole. The inner bolt rod is inserted into the through axlehole from an end opening in one end of the outer bolt head, and the tail end of inner bolt rod penetrates out of the tail end of the outer bolt rod. The tail end of the inner bolt rod is provided witha first outer thread. The inner bolt is additionally arranged to penetrate the outer bolt to be further screwed and locked, during fastening using, the inner bolt and the outer bolt are mutually restrained, and therefore loosing is not prone to occurring, and the anti-loosing effect is improved.

The invention discloses a lock washer manufacturing method and a lock washer. The manufacturing method comprises the following steps that (1), the lock washer which is made of stainless steel and has a tooth structure is manufactured, wherein the tooth structure is that the included angle between a long edge and a short edge of the cross section of a small tooth is 80-110 degrees, the depth of the small tooth is 0.1-0.3 millimeter, the included angle between the long edge of the cross section of the small tooth and the base plane of the washer is 5-10 degrees, and the included angle A between the long edge of the cross section of a large tooth and the base plane of the lock washer is larger than the lead angle B of a matched bolt or nut by 0.1-1 degree; (2), the surface of the lock washer is processed, and a passivated layer on the surface of the lock washer is removed; (3), the lock washer after processing of the step (2) is subjected to low-temperature carburization, or low-temperature nitridation or low-temperature nitrocarburizing, and a hardened layer is formed on the surface of the lock washer; (4), the finished lock washer is finally manufactured after washing. The lock washer manufactured through the manufacturing method is good in lock effect and low in manufacturing cost.

The invention discloses an anti-loose bolt set composed of a stop washer and an annular groove nut and an operation method thereof. Through interaction of upright external teeth of the stop washer anda wedge-shaped groove face of the annular groove nut, one radial acting force is added besides axial pretightening force when thread pairs are pretightened, and larger pressure and friction force areformed between the thread pairs. Meanwhile, an additional friction acting point is further added due to the interaction of upright external teeth and the wedge-shaped groove face, thus additional pressure and friction force are increased, the total friction force limit value is increased and is much larger than a friction force limit value generated by a common pretightening bolt, the anti-loosebolt set is better in anti-loose effect, and thus the thread pairs can be prevented from rotating relatively. The anti-loose bolt set is good in reliability and practicability, and can be used for places with severe impact, vibration and alternating load or with large temperature change, maintenance and overhauling of thread connection is reduced effectively, the safety of utilizing of the anti-loose bolt set is improved, and the utilization rate of the anti-loose bolt set is increased.

The invention discloses an elastic washer, which is n-shaped as a whole and includes an integrally formed body and an outwardly curved elastic cantilever. After the elastic washer is placed between the connecting devices, the elastic cantilever is pressed close to the body of the elastic washer. When there is a gap between the connecting devices due to looseness, the elastic cantilever will rebound and resist one of the matching connecting devices to prevent the connecting devices from loosening.

The invention relates to a bundled conductor supporting armor clamp. The armor clamp comprises a connecting base plate fixedly connected to a supporting insulator, a direction corresponding to an extension direction of a bundled conductor is defined as an installation direction, the connecting base plate is provided with at least two spacer installing plates which are distributed separately along the installation direction successively, each spacer installing plate is provided with a spacer in the side surface vertical to the installation direction, each spacer includes lead clamps arranged along the circumferential direction of the spacer, and the number of the lead clamps of each spacer is the same with that of the other spacers. Separate distribution of the bundled conductor is realized, and the bundled conductor is supported so that the bundled conductor is prevented from downward swinging due to the deadweight. The connecting base plate is provided with at least two spacer installing plates which are distributed separately, multi-point support for the bundled conductor is formed, stress concentration in the bundled conductor is alleviated effectively, bearing of the bundled conductor is optimized, and the power transmission stability and reliability of the bundled conductor are improved.

The invention belongs to the technical field of screw fasteners and particularly relates to an anti-loosening screw fastener connection structure. The anti-loosening screw fastener connection structure comprises a part A, a part B, a screw and combined nuts, wherein the part A and the part B are connected by the cooperation of the screw and the combined nuts. The screw comprises a head, a positioning section and a threaded section, wherein the head is of a hexagonal prism structure. The combined nuts comprise an inner nut and an outer nut both of which are threadedly connected through the threaded section of the screw, wherein the inner nut is installed between the part B and the outer nut. The inner nut and the outer nut are respectively provided with mutually matched conical bosses and grooves, wherein the bosses and the screw are arranged concentrically, the grooves and the bosses are arranged eccentrically, and the eccentric distance is 1 / 20 of the pitch diameter of the bosses. Theinner nut includes a hexagonal prism section and a cylindrical surface section, wherein the cylindrical surface section is inserted into the outer nut. The side of the outer nut is provided with a spring pin at a position corresponding to the cylindrical surface section.

The invention provides a workpiece clamping device, and belongs to the technical field of machining. The workpiece clamping device comprises a clamping assembly and a limiting assembly. The lower end of a rocker of the clamping assembly is hinged to a rocker supporting base, and the upper end of the rocker and the lower end of a connecting rod are hinged through a first hinge pin. A bent press plate is hinged to a press plate supporting base through a second hinge pin, one end of the bent press plate and the upper end of the connecting rod are hinged, and a press cushion is arranged on the lower side of the other end of the bent press plate. One end of a piston rod of a driving cylinder and the first hinge pin are hinged. A left supporting plate and a right supporting plate of the limiting assembly are symmetrically arranged on the two sides of a machine frame. A left stop screw penetrates through the left supporting plate, and a first supporting nut and a first locking nut are in threaded connection with the left stop screw. A right stop screw penetrates through the right supporting plate, and a second supporting nut and a second locking nut are in threaded connection with the right stop screw. The workpiece clamping device has a good clamping effect on workpieces, effectively prevents the workpieces from moving in the machining process, and is reasonable in structure and low in cost.

The invention relates to the technical field of accessories for automobile oil pipes, and particularly relates to an improved pipe clamp for an automobile oil pipe. The pipe clamp comprises lower pipeclamps, a connecting part, a protruding part, upper pipe clamps and a driving mechanism, wherein the driving mechanism comprises a screw, a swivel nut and hinge rods. The pipe clamp has the beneficial effects that by rotating the screw, the swivel nut is driven to move vertically on the screw, the two hinge rods are driven to swing, the upper pipe clamps are caused to rotate along the hinge jointwith the protruding part, the upper pipe clamps are combined with the lower pipe clamps, so that the oil pipes are clamped, the mode that the upper pipe clamps and the lower pipe clamps are driven tobe combined through thread screwing in the prior art is replaced, the time of operation is at least reduced to some extent, and the assembly efficiency is improved. In addition, the upper pipe clampdo not follow rotation, the assembly efficiency is further improved, meanwhile, the clamping force of the two upper pipe clamps to the oil pipes is basically consistent, and then the clamping force ofthe upper pipe clamps to the oil pipes is conveniently adjusted.

The invention relates to a common grounding structure. The structure comprises a mounting bolt, a mounting nut, a wiring bolt and a wiring nut, the mounting bolt and the wiring bolt are connected to form a double-head grounding bolt of an integrated structure through a boss, and the two side surfaces of the boss are a common conduction contact surface and a wiring conduction contact surface; the mounting nut and a mounting covering cap sleeve the periphery of the mounting bolt from inside to outside, the wiring nut and a wiring covering cap sleeve the periphery of the wiring bolt from inside to outside, and the diameter of the boss is larger than the diameters of the mounting bolt and the wiring bolt. According to the common grounding structure, it can be guaranteed that the conduction contact surfaces are not easily corroded, the electric performance is not easily aged and lowered, the technology is convenient and easy to implement, the anti-loosening and protection effects are extremely good, and the production cost is low.

The invention discloses a flange nut loose-proof sleeve. The technical essential scheme is as follows: a connecting sleeve (2) is at least fixedly connected with two nut sleeves (1); the nut sleeves (1) are sleeved in the nuts of bolts on a corresponding flange; and the connecting sleeve (2) is fixed on a fixing device (6) on a flange outer side surface(4).

The invention discloses an anti-loosening bolt assembly, which can effectively prevent nuts from loosening and can be disassembled. It consists of a bolt (1), a nut (8), and a stop snap ring sleeve, and is characterized in that: a stop groove (3) is arranged in the axial direction of the bolt (1); the stop snap ring sleeve is composed of ring pieces (4 ), a compression piece (5), a stop protrusion (6), and a bolt passage hole (7), and a compression piece (5) capable of producing elastic deformation is fixed on the ring piece (4) of the stop snap ring sleeve , the ring piece (4) is provided with a bolt channel hole (7), on the radial inner edge of the ring piece (4) is provided with a stop protrusion (6) corresponding to the stop groove (3), the stop card The ring sleeve passes through the bolt (1) through the bolt channel hole (7) so that the stop protrusion (6) enters the stop groove (3) of the bolt (1), and presses the pressing piece (5) to the nut (8) up. Figure 3 is the accompanying drawing of the abstract of the description.

The invention relates to the field of electric connectors, in particular to a rectangular electric connector with a locking function and a component of the rectangular electric connector. The front end of the electric connector serves as a plugging end. The electric connector comprises a shell and a locking fastener, wherein the locking fastener comprises two ribs which are parallel to each other and a transverse arm which is connected between the two ribs; the two ribs are respectively hinged on the left and right sides of the shell; the transverse arm is positioned above the shell; a locking groove is formed on each rib and provided with an opening into which a lug on an adapter connector is inserted; a limiting groove is formed on the inner side face of at least one of the two ribs; a limiting block which is used for limiting a forward rotation angle of the locking fastener is arranged on the opposite side face of the shell; the limiting block is protruded into the corresponding limiting groove; and in the plugging process of the electric connector and the adapter connector, when the forward rotation of the locking fastener is limited by the limiting block, the opening of the locking groove faces the lug on the adapter connector. By the invention, the problem of inconvenience for operation of the conventional rectangular electric connector with the locking fastener is solved.

The invention discloses a planar self-locking connecting device, which is used for connecting separate plane objects. The planar self-locking connecting device comprises a connecting piece and a self-locking nut assembly, wherein the self-locking nut assembly comprises a bolt and a self-locking nut which is locked with the bolt mutually in a bolt connection manner; the self-locking nut is axially provided with at least two slots for self-locking; and the self-locking nut is radially limited on the connecting piece. Aiming at the defects of poor firmness and easy release, owing to the fact that two soft objects with less thickness are in bolt connection directly through the bolt, in the prior art, the invention provides the planar self-locking connecting device which has the characteristics of firm connection, convenience for disassembly and good anti-looseness effect.

The invention provides an anti-loosening connecting bolt. The anti-loosening connecting bolt comprises a bolt and a nut which are connected with a joint surface part, wherein at least one V-shaped groove is formed in the joint end surface of the nut and the joint surface part; a metal stop elastic sheet is arranged between the nut and the joint surface part; a stop boss is arranged on one side, incontact with the joint surface part, of the metal stop elastic sheet; a groove matched with the stop boss is formed in the joint surface part; a stop sheet is arranged on one side, in contact with the nut, of the metal stop elastic sheet; and after the nut is fastened and is in a proper position, the metal stop elastic sheet can be meshed with the V-shaped groove in the nut under the action of elastic force, so that the anti-loosening and stop effects are achieved. The anti-loosening connecting bolt has the characteristics of reasonable and feasible structure, reliable anti-loosening effect,wide application range, easiness in manufacturing, convenience in mounting, capability of being repeatedly dismounted and used and long service life.

The invention provides a combined locknut capable of being prevented from automatically unlocking on a bolt. The combined locknut comprises a fastening nut, a lock washer, a spring washer and a compressing nut. The combined locknut is characterized in that a limiting groove is formed in the fastening nut; a locking lug and a returning stopping lug are arranged on the lock washer; anti-slip teeth are arranged on the compressing nut. According to the combined locknut, a workpiece on the bolt is fastened through the fastening nut; then the bolt is sleeved with the lock washer and the spring washer sequentially, and the locking lug on the lock washer is embedded into the limiting groove in the fastening nut; the compressing nut is screwed and compressed; the returning stopping lug on the lock washer is inserted into tooth grooves of the anti-slip teeth on the compressing nut, so that the fastened fastening nut, the lock washer, the spring washer and the compressing nut can form a fastening body; a large frictional force remains between the body and threads of the bolt all the time. Therefore, the combined locknut has a good locking effect; and in addition, the combined locknut is simple to operate, and can be repeatedly used.

The invention particularly discloses an axial flow ventilator capable of synchronously adjusting blades, and is used for solving the problems of time waste and labor waste during adjustment of mounting angles of the blades of the conventional axial flow ventilator and the problem of influence of unbalance of a blade wheel on the service life of the conventional axial flow ventilator. A push disk is sleeved on a shaft sleeve; a groove is formed on the outer cylindrical surface of the push disk; a crank is arranged in the groove; a worm wheel which is in threaded connection with the push disk is arranged on the right side of the push disk; a supporting seat and a cover plate are arranged on the outer sides of the left end face and the right end face of the worm wheel; a worm support is fixed on the supporting seat; a worm is inserted into the worm support; a balance weight rod is arranged on the other side of the worm; a driving rod is fixed at one end of the worm; the outer end of the driving rod is positioned in a supporting sleeve; a clamping slot is formed on the stair surface of the supporting sleeve; a pin shaft is inserted into a sliding chute hole of the driving rod; a sealing gasket is sleeved on the driving rod; and a spring is arranged between the sealing gasket and the pin shaft. According to the axial flow ventilator, the efficiency of adjusting the mounting angles of the blades is improved, and the consistency of the mounting angles is guaranteed; and the axial flow ventilator has the advantages of simple structure, low cost and convenience in maintenance, and is easy to mount.

The invention relates to the technical field of fasteners, in particular to a fastener with an anti-loosening function. The fastener comprises a bolt head, wherein the bottom end of the bolt head is connected with a threaded section; the upper end of the threaded section is connected with a convex ring; the threaded section is connected with a first nut; the threaded section is connected with a second nut; the bottom end of the first nut is connected with a plurality of first connecting rods; one end of each first connecting rod is connected with the second nut; the bottom end of the threadedsection is provided with a hollow sleeve in a sleeving manner; the bottom end of the outer side of the hollow sleeve is connected with a hexagonal bulge; the interior of the hollow sleeve is connectedwith a threaded rod; a threaded hole is formed in the bottom end of the threaded section; and the upper end of the hollow sleeve is connected with a supporting frame. According to the fastener, the hexagonal bulge drives the hollow sleeve to rotate, the hollow sleeve drives the threaded rod to rotate, the threaded rod is connected with the threaded hole, the hollow sleeve rotates upwards to drivethe supporting frame to move, the upper end of the supporting frame is in contact with the second nut, when the first nut is loosened, the second nut prevents the first nut from being loosened through the first connecting rods, and the anti-loosening effect is good.

A lock nut comprises an outer nut and an inner nut. A first internal thread is formed inside the inner nut. An external thread is formed in the lower end of the outer wall of the inner nut. A second internal thread is formed in the middle inside the outer nut. A third internal thread is formed in the bottom end inside the outer nut. The inner nut is installed inside the outer nut. The external thread and the second internal thread are consistent in screwing direction. The external thread and the first internal thread are opposite in screwing direction. The external thread and the third internal thread are opposite in screwing direction. The distance between a first plane at the bottom of the inner nut and a second plane below the second internal thread inside the outer nut is not smaller than the one-fold screw pitch. The lock nut has the beneficial effects that a bolt cannot loosen after the bolt is screwed down by hand and the left-hand and right-hand threads are meshed, and the anti-looseness effect is good; the structure is simple, looseness prevention can be achieved by easy nut and bolt fastening; installation is convenient; the optional bolt range is wide; when the bolt is screwed down, the bottom face of the head of the bolt and the top face of the inner nut are not in contact, and therefore the needed pretightening force is much smaller than that in the prior art.

The invention provides a self-locking fastening set which mainly solves the problem that in the prior art, a fastener is likely to get loose in the vibration environment and consequently connection looseness is caused. The self-locking fastening set comprises a bolt, an inner nut and an outer nut, wherein the outer nut is provided with a fastener locked to the lower end face of the inner nut, the outer nut is sequentially provided with a first hole, a second hole and a threaded hole from top to bottom, the fastener is arranged in the second hole, a thread column is arranged in the threaded hole, and a spiral spring is arranged between the thread column and the fastener; the thread column is rotated, so that the upper end of the fastener stretches out of the first hole and is locked to the lower end face of the inner nut in a tightly attached mode, and the outer nut is effectively prevented from getting loose, and the anti-looseness effect is improved; in combination with an accompanying drawing, optimization modes for two kinds of fasteners including steel balls and stepped cylinders are detailed. The self-locking fastening set is simple in structure, can effectively prevent the outer nut from getting loose and provides reliable fastening connection.

The invention discloses a special-shaped anti-rotation self-locking retainer ring which comprises a component body (1). The component body (1) is in the shape of a short pipe with a closed end, a special-shaped hole (2) which coincides with the axis of the short pipe is formed in the closed end of the short pipe, external threads (4) are arranged on an outer cylindrical surface of the short pipe, and sunken deformation pits (3) which are circumferentially uniformly distributed are formed in the inner wall of the short pipe; screwing notches (5) which are circumferentially uniformly distributed are arranged on the end surface of an unclosed end of the short pipe. The special-shaped anti-rotation self-locking retainer ring has the advantages that the special-shaped anti-rotation self-locking retainer ring has a self-locking function and anti-rotation capacity, is sufficient in strength, firm and reliable in connection and particularly applicable to limiting axial positions of components in holes after the components are assembled in the holes, and can be used for other places with high axial loads.

The invention discloses a gas extraction device in a coal mining area. By setting a high frequency oscillator, the gas can be completely extracted and the gas flow can be promoted. In the process of gas extraction, a plugging assembly is firstly used to mount and position an extraction pipe and after well plugging, good sealing performance is ensured; later, an extraction pump is used, a control valve is controlled, the gas is firstly extracted, after the gas is extracted to a certain degree at an extraction hole, the high frequency oscillator is used to oscillate, and after a certain period of continuous extraction, a pulse aeration module is opened again, a protective gas is impulsively injected into a coal seam, after certain pressure arrives in the borehole in a certain time of pulse aeration, the gas in the borehole is continuously extracted, and thus, the high frequency oscillator is used to promote circulation of the gas, the extraction effects are ensured, the remaining small part of gas is subjected to exchange and circulation by using a pulse aeration mode, and the gas is completely extracted.