96results about How to "Ensure vibration" patented technology

The invention discloses a pedal type continuous vibration piezoelectric generating device. The device mainly comprises a pedal which is mounted at the position of an opening in the center of an upper cover of a box body through a spring mechanism, and the pedal drives N groups of ratchet mechanisms to link a vibration piezoelectric generator through a gear mechanism, wherein N is a natural numberexcept zero. After the pedal is stepped, acting energy is transferred to a flywheel through the gear mechanism and the ratchet mechanisms, and a pick tray is driven by the flywheel which continuouslyrotates in one direction to move a metal sheet of a cantilever beam and ensure the continuous vibration of the cantilever beam. The invention can bear repeated stepping, converts the intermittent stepping power of a stream of people into the continuous vibration of the cantilever beam, and the energized piezoelectric sheet can accordingly generate continuous electric power output so as to finallyreach the aim of effectively accumulating the electric power.

The invention provides a device and a method for detecting high-temperature vibration fatigue characteristics of an aero-engine blade. A vibration loading system is used to apply a vibration load to an aero-engine blade, and the aero-engine blade is heated and controlled by an electric induction heating system; a three-dimensional digital image correlation method is utilized to detect and analyzethe vibration fatigue characteristics of the aero-engine blade under a high temperature vibration load. The invention utilizes the three-dimensional digital image correlation method of non-contact optical full-field deformation measurement, and can adapt to measurement under various scales and various conditions; the accuracy of the detection result is ensured; vibration fatigue monitoring of theaero-engine blade can be achieved at different temperatures and different frequencies; and the comprehensiveness of the experimental result can be ensured.

The invention relates to a method for testing polymer composite material rheological characteristic and a device thereof. The invention can measure the rheological actions of polymer composite material during an extrusion molding process, a capillary extrusion process and an injection molding process under the function of physical field enhancement and also can measure the rheological action of the polymer composite material when processing condition and parameter are changed according to a specific program. The invention uses a servo motor, a ball screw, an excitation system and a digital intelligent servo system to control the rheological testing process of the polymer composite material exactly, and the invention can measure the rheological characteristic of high polymer complex liquid continuously and fast under different processing conditions during the process of a single experiment. The invention can quench fused mass sharply during the testing process and then samples and studies the rheological characteristic of polymer fused mass intuitively. The invention has the high accuracy and stability of measurement data and the wide application range of material and is fit for macromolecular material, a macromolecule blending system, a macromolecule filling system, other similar macromolecular liquid systems, etc.

A fluid-filled vibration damping bushing including an inner tubular metal member and an outer peripheral sleeve elastically connected via a base rubber interposed therebetween with first and second fluid chambers formed therein. A stopper rubber constituted as a separate element from the base rubber, disposed at a circumferential location corresponding at a minimum to either the first or second fluid chamber, for restricting relative displacement of the inner tubular metal member and outer tubular metal member in an axis-perpendicular direction. The stopper rubber is formed separately from an orifice member and bonded to one axial end portion of the outer tubular metal member at a location outside the first and second fluid chambers so as to face toward the inner tubular member. The outer tubular metal member with the stopper rubber attached thereto is inserted onto the outer peripheral sleeve from the other axial end thereof.

A fluid-filled vibration damping bushing including an inner tubular metal member and an outer peripheral sleeve elastically connected via a base rubber interposed therebetween with first and second fluid chambers formed therein. A stopper rubber constituted as a separate element from the base rubber, disposed at a circumferential location corresponding at a minimum to either the first or second fluid chamber, for restricting relative displacement of the inner tubular metal member and outer tubular metal member in an axis-perpendicular direction. The stopper rubber is formed separately from an orifice member and bonded to one axial end portion of the outer tubular metal member at a location outside the first and second fluid chambers so as to face toward the inner tubular member. The outer tubular metal member with the stopper rubber attached thereto is inserted onto the outer peripheral sleeve from the other axial end thereof.

The invention discloses an ultralow-temperature and ultralow-vibration friction testing device, which comprises a helium liquefying mechanism, a friction mechanism and a storage tank, wherein the helium liquefying mechanism comprises a first vacuum hood and a first cold shield arranged in the first vacuum hood; a refrigerator penetrates through the first vacuum hood; a first-level heat exchanger and a second-level heat exchanger connected with a liquid conveying pipe are arranged on the refrigerator; the first-level heat exchanger and the second-level heat exchanger are positioned in the firstcold shield; the friction mechanism comprises a second vacuum hood, a second cold shield and an insulating bracket; the second cold shield and the insulating bracket are arranged in the second vacuumhood; the second vacuum hood is connected below the first vacuum hood; a liquid helium cavity is formed in the second cold shield; an exit of the liquid conveying pipe is formed in the liquid heliumcavity; an upper sample support is arranged on the outer bottom wall of the second cold shield; a movable displacement platform is arranged on the insulating bracket; a lower sample support is arranged on the displacement platform; the upper sample support and the lower sample support face each other up and down; the storage tank is connected with the first-level heat exchanger through a gas supplementing pipe and connected with the liquid helium cavity through a gas return pipe. According to the invention, a friction test of a sample can be realized in an environment with ultrahigh vacuum degree and ultralow temperature.

The invention discloses a ball spacing type repeated folding-unfolding wheel locking and unlocking mechanism. A ball spacing device is used for realizing the axial and circumferential motion conversion of a hub, i.e. when the hub moves along the axial direction in sequential motion, an axial push rod hinged with the hub carries out planar motion so as to drive a radial push rod fixedly connected to a hub sloping block to move along the radial direction, thereby regulating the radial size of a wheel; when the hub rotates along the circumferential direction in the sequential motion, the hub, a wheel axle, spokes and a wheel rim of the ball spacing type repeated folding-unfolding wheel locking and unlocking mechanism are formed into an integral wheel structure; the wheel is under the locking state; and the wheel can be driven to rotate so as to realize the driving function of the wheel. According to the ball spacing type repeated folding-unfolding wheel locking and unlocking mechanism disclosed by the invention, the radial size of the wheel can be effectively regulated according to different terrain conditions, the defect that the traditional moving obstacle-crossing probe vehicle has a poor adaptive capacity on the non-structural terrain can be overcome, and the terrain adaptability of the wheel is effectively improved.

A window regulator which attenuates vibrations of a wire, which are generated when the door is closed while a window glass is constrained at the top end of the window, to suppress the generation of an abnormal noise. The window regulator includes a carrier plate coupled to a vehicle window glass, a driving unit which lifts and lowers the carrier plate and is disposed below a lower limit of lifting and lowering of the carrier plate, a lifting wire having one end coupled to the carrier plate and another end coupled to the driving unit via a direction-changing member, and a lowering wire having ends coupled to the carrier plate and the driving unit, respectively. An attenuation member is provided on the lifting wire interposed between the direction-changing member and the driving unit and makes contact with the lifting wire to attenuate vibrations when the lifting wire vibrates.

The invention relates to the technical field of lotus root harvesting, and discloses an integrated lotus root harvesting and digging device which comprises a frame. A first piston cylinder is slidablyconnected onto the frame, a first piston plate is slidably connected into the first piston cylinder, a supporting rod is arranged on the first piston plate, a connecting plate is arranged on the supporting rod, a first scraper pan and a second scraper pan are rotatably connected onto the connecting plate, the connecting plate, the first scraper pan and the second scraper pan enclose a closed cavity, meshes are formed in the connecting plate, the first scraper pan and the second scraper pan, a first magnet is arranged on the first scraper pan, a second magnet is arranged on the second scraperpan, hoses are distributed in the connecting plate, the first scraper pan and the second scraper pan, water inlets are formed in the hoses, free balls and flexible block pieces are arranged in the hoses, a second piston cylinder is arranged on the first scraper pan and communicated with the first scraper pan, a second piston plate is slidably connected onto the second piston cylinder, and a connecting rod is arranged on the second piston plate. By the aid of the integrated lotus root harvesting and digging device, lotus roots are simultaneously dug and cleaned, and lotus root harvesting efficiency is improved.

An object is to provide an inverter module that can ensure satisfactory anti-vibration strength, moisture resistance, and isolation for each of the upper and lower boards of the inverter module and that can reduce the weight and cost, and to provide an integrated-inverter electric compressor. In an inverter module (21) in which a power system board (23) and a control board (31) are integrated via a resin case (22), the inverter module (21) is configured such that the power system board (23), on which a semiconductor switching device (24) is mounted, is provided at the lower part of the resin case (22) and the control board (31), on which a control-and-communication circuit is mounted, is provided thereabove. In the resin case (22), a thermosetting resin (36) is filled to a height position where the top surface of the power system board is covered (23), so that the power system board (23) is encapsulated in the resin, and a gel-like resin material (38) is filled from a resin-encapsulated surface (37) to a height position where a part of the control board (31) is covered.

A lens drive device (101) capable of ensuring that the vibration in the optical axis direction converges in a short period of time even when a strong impact is applied due to, for example, a drop is provided with a cylindrical lens holding member (2) that can hold a lens body; a force applying member (3) that supports the lens holding member so as to be movable in the optical axis direction; a fixing side member (R4) that fixes a part of the force applying member; a drive mechanism (M5) that moves the lens holding member in the optical axis direction. The force applying member has an upper leaf spring (3A) fixed to an upper portion of the lens holding member; the upper leaf spring having a first portion (13) fixed to the lens holding member, a second portion (23) fixed to the fixing side member, an elastic arm portion (53a) provided between the first portion and the second portion, and an extending portion (63) extending from the first portion; a damping port (GE) is arranged to striding over the extending portion and the fixing side member.

The invention provides a debris flow prevention and treatment system. The debris flow prevention and treatment system can solve the problem that after water and stone of the debris flow are separated,stone blocks block a cover plate with holes and guarantee the debris flow water and stone separation system can durably and effectively play the role. The debris flow prevention and treatment systemcomprise a drainage system and a vibration system. The drainage system comprises a water collecting pool, the cover plate with the holes and a drainage pipe. The vibration system comprises a rotatingrod, a fixing shaft, a pedal, a support block and a spring. The debris flow prevention and treatment system can achieve effective control over the formation process and circulation process of the debris flow and solve the treatment problems of different scales of debris flow gullies. Soil and stone are separated from water by means of the water collecting pool and the drainage pipe, so that the hydrodynamic condition of the debris flow is weakened, and the damage power of the debris flow is reduced. The vibration system utilizes the kinetic energy of large stone blocks in the debris flow as power and can continuously and effectively guarantee that vibration happens, and therefore the cover plate is prevented from being blocked; and in this way, the drainage system can stably play the role,and effective prevention and treatment of the debris flow are achieved.

The invention relates to a precast concrete member mold added with a flat cover for pressing. The precast concrete member mold added with the flat cover for pressing comprises a mold body, a pressingflat cover, a first transverse supporting plate, a driving vibrating mechanism, a buffering protective mechanism and a locking limiting mechanism. According to the precast concrete member mold added with the flat cover for pressing, the pressing flat cover is added to the mold body; the arrangement of the pressing flat cover can achieve an effect of flattening concrete slurry, and meanwhile, can achieve an effect of preventing splashing in a concrete preparation process; moreover, the driving vibrating mechanism is also added on the pressing flat cover; the arrangement of the driving vibratingmechanism can realize the height adjustment of the pressing flat cover, and can also ensure the pressing flat cover to realize a vibrating effect; therefore, the solidification of the concrete slurryis realized, so that the probability of generating air bubbles is reduced; in the addition, conventional manual processes are replaced by mechanical solidifying and flattening, so that the productionefficiency can be effectively improved; and moreover, high efficiency of the solidifying and flattening can be ensured.

The invention relates to a brushless direct current permanent magnet motor having characteristics of low noise, low vibration and low temperature rise. The brushless direct current permanent magnet motor consists of a motor rotor, a motor stator, a front end cap, a motor housing and a rear end cap. The front end cap and the rear end cap are sealedly installed at two ends of the motor housing to form an integral motor housing; the motor stator is arranged inside the motor housing; and the motor rotor is installed inside the motor stator. The brushless direct current permanent magnet motor is characterized in that: an iron core of the motor stator is formed by lamination of a plurality of punching sheets that are manufactured by Fe-Ni soft magnetic alloy; the punching sheets are in a circular ring shape and grooves that are arranged regularly are made on inner circles. When the plurality of punching sheets are laminated, an angle is formed by staggering of the grooves of adjacent punching sheets, so that a chute is formed at a stator slot; and an enameled wire is wound in the chute. According to the invention, a heat dispersion performance, a stator lamination mode and a balancing performance are improved; therefore, the motor has characteristics of high rotating speed, low noise, low vibration and low temperature rise as well as is suitable for application to a special using occasion. When the motor that is assembled by the assembly technology in the invention works at 7000RPM, the temperature rise is not more than 12 DEG C and the noise is less than 60dB.

The invention discloses a differential type optical fiber F-P vibrating sensor with a wide frequency response and high sensitivity. The differential type optical fiber F-P vibrating sensor is mainly composed of a balance weight body (1), a reflector (2), a first V-shaped cantilever beam (4), a second V-shaped cantilever beam (5), a fixed base (6), a packaging box contact position (8), an optical fiber micro lens (9) and a tail fiber (10). Response frequency and sensitivity of the first V-shaped cantilever beam and the second V-shaped cantilever beam compensate each other, the sensor is high in sensitivity, and the frequency response range reaches 50 Hz-10,000 Hz. When external vibration acts on an F-P cavity through the action of the double cantilever beams of the sensor, a reflecting light signal changes along with the reciprocating change of the balance weight body, and therefore an optical light reflected back by the F-P cavity is changed, and external vibration parameters are obtained by measuring the change amount of the signal. The differential type optical fiber F-P vibrating sensor is simple in structure and convenient to use, the optical signal is not interfered with an electromagnetic field, and the sensor can work quite effectively and precisely, and is simple in structure and low in cost.

The invention discloses an efficient and long-service-life hydraulic valve main hole machining method, and belongs to the hole machining technology field. In the machining method, an oil port three-blade forming cutter, a three-blade chambering cutter and an eight-blade expanding reamer are sequentially used for machining a main hole of a hydraulic valve. One-time forming of a forming hole is guaranteed through the oil port three-blade forming cutter, a service life is long, and cutting efficiency is high. An unequal design of the three-blade chambering cutter is matched with a layered structure design so that chambering cutting vibration is reduced, a chambering machining allowance is large, concentricity of the main hole of an intermittent hydraulic valve is ensured, and machining precision and machining efficiency are high. Unequal parts of the eight-blade expanding reamer are combined with unequal teeth so that vibration of a cutter of expanding and reaming is greatly reduced, andsurface roughness and cylindricity of the main hole of the hydraulic valve, the reaming processing allowance and the cutting efficiency are improved; and the method has the advantages of high machining efficiency, good machining precision, a long service life of the cutter and the like, and a problem that hydraulic valves are scrapped due to blockage of ducts by residual cuttings is effectively solved.

The invention discloses a single-mass vibration fuzzy image acquisition and vibration parameter visual measurement experiment platform. The platform comprises a single-mass vibrator and a camera. The single-mass vibrator is connected with a vibrator exciter, the vibration exciter is controlled through a frequency converter, the vibration exciter drives the single-mass vibrator to vibrate, the single-mass vibrator is connected with the camera, and an independently fixed visual scaling board is arranged below the lens of the camera. According to the invention, the single-mass vibrator vibrates under the effect of the vibration exciter, a binocular stereo camera connected with a timbre vibrator vibrates together, and fuzzy images during vibration can be acquired through the lens of the vibrating camera. The experiment platform provides an experiment means for realizing acquisition of the vibration fuzzy images and image restoration. Research data under different vibration conditions can be obtained by changing the frequency and amplitude of the vibration conveniently through the frequency converter. An ideal experiment means is provided for analysis of degradation causes of the vibration fuzzy images, restoration of the vibration fuzzy images and vision-based vibration parameter measurement.

The invention provides an ultrasonic vibration head structure. The ultrasonic vibration head structure can well guarantee the uniformity of ultrasonic transmission, and further improve the ultrasonic cleaning effect. The ultrasonic vibration head structure comprises an ultrasonic vibration head body. The ultrasonic vibration head body comprises an ultrasonic vibration head body head end and an ultrasonic vibration head body tail end. The ultrasonic vibration head structure is characterized in that the ultrasonic vibration head body head end is of a hollow structure, and a plurality of vibration pieces are arranged in the hollow structure and connected through springs.

The invention discloses a building construction method of an interior wall. The construction method comprises the steps that (1) concrete is prepared, specifically, building debris is subjected to smashing operation through a smashing device, thus broken stones are prepared, then the broken stones, cement, water and a water reducing agent are evenly mixed through a stirring machine to get a raw material A, and then a compound A is prepared after an expanding agent is added into the raw material A and stirring is conducted continuously; (3) a wall is bricked, specifically, reinforcing steel bars are erected at the positions, corresponding to the indoor wall, of a construction site, and a brick wall is piled up on the outer portions of the reinforcing steel bars; and (4) a wall body is formed, specifically, concrete is poured into the brick wall and the reinforcing steel bars, and the wall body is formed after the concrete is solidified. According to the construction method of the indoorbuilding wall, sand and stones are directly manufactured through the building debris, and waste of non-renewable resources is effectively avoided. Investment of building debris treatment is omitted,the project cost is effectively lowered, and meanwhile the municipal administration cost can be lowered to a large extent. The input amount of water when the concrete is prepared is effectively decreased by adding the water reducing agent, resources are further saved, and the project cost is reduced.

The invention relates to a bearing testing machine based on three-direction vibration. The bearing testing machine based on three-direction vibration comprises a test bench; a test main body arranged above the test bench; a radial loading device used for applying a radial acting force to the test shaft; a driving device which is arranged on one side, in the axial direction of the test shaft, of the test main body and used for driving the test shaft to rotate; a transverse vibration device which is arranged on the other side, in the axial direction of the test shaft, of the test main body and used for providing transverse vibration; a vertical vibration device which is arranged on one side of the test main body in the vertical direction and is used for providing vertical vibration; a longitudinal vibration device which is arranged on one side of the test main body in the horizontal direction and is used for providing longitudinal vibration; and an air spring which is positioned between the test main body and the test bench so that the test main body is assembled above the test bench in a floating manner. The test main body is assembled above the test bench in a floating manner through an air spring so as to ensure that the test main body can vibrate in the transverse direction, the longitudinal direction and the vertical direction.

The invention belongs to the field of moulding manufacturing of rubber products, and discloses a rubber dynamic injection moulding device and method. The device comprises a rubber cold feeding screw extruder, a sliding ring, a vibration sleeve, an injection nozzle, an upper cushion plate, an upper form board, a lower form board, a lower cushion plate and an electro-hydraulic hydraulic vibration system which are connected in sequence. According to the device, a vibration field is stacked at the position of an injection mold. According to the method, on the basis of not changing the mold structure and the material formula, the vibration field is stacked in the main shear direction of rubber to change the fluidity of rubber materials. According to the dynamic injection moulding device and method, the rubber filling capacity can be enhanced, injection pressure can be reduced, energy consumption can be reduced, and product quality can be improved; and especially it is possible to moulding the large-size and high-quality rubber products.

The invention discloses a human breath energy collecting device. The human breath energy collecting device comprises a breath airflow power assembly and a piezoelectric harmonica cavity assembly, wherein the breath airflow power assembly comprises a gauze mask, a connector and a communication pipe, the connector is arranged on the gauze mask and located below the nose of a human, and the connector is connected with the piezoelectric harmonica cavity assembly through the communication pipe; the piezoelectric harmonica cavity assembly comprises a vibrator fixing tube and a piezoelectric vibrator, the tail end of the vibrator fixing tube is a breath airflow inlet and outlet, an opening is formed in the middle section of the vibrator fixing tube, the piezoelectric vibrator is arranged on the opening in the axial direction, one end of the piezoelectric vibrator is fixed to the vibrator fixing tube, and the other end of the piezoelectric vibrator is suspended to form a cantilever beam structure. Through the human breath energy collecting device, the resonant frequency of reeds can be determined according to the breathing frequency; through the arrangement of the cantilever beam structure of the piezoelectric vibrator, it can be well guaranteed that piezoelectric ceramics can vibrate under the resonant frequency and the strongest deformation can be generated, and consequently the largest piezoelectric energy can be stimulated.

The invention discloses a portable anti-overpressure exhaust valve leakproofness detection device, which comprises a detection device main body, wherein the top of the detection device main body is hinged to a protection end cover, one side of the inner side of the detection device main body is fixedly provided with an operation machine box, the other side of the inner part of the detection device main body is provided with a detection chamber, a wind speed detector is fixedly installed on one side of the interior of the detection cavity, a temperature detector is cooperatively installed at the position, which corresponds to the position over the wind speed detector, of the interior of the protection end cover, and by designing a spraying assembly installed on the detection device main body, protection spraying treatment on the device is achieved, and the situation that the detection result is affected by crushed materials, dust and the like in the exhaust valve assembly wrapping detection process is avoided. Meanwhile, the detection direction of the device is increased by means of the wind speed detector and the temperature detector which are designed and installed on the inner side of the detection device body, and the detection result is more accurate.

An awning comprisestwo holding brackets arranged on a base member between which a fabric shaft is mounted for rotation;an awning fabric which is windable in on or out on the fabric shaft; anda motor drive for rotating the fabric shaft, which motor drive is installed in the awning shaft and is mounted on one of the holding brackets in a vibration-damped manner, anda vibration insulation device which is completely arranged inside the fabric shaft between the motor drive and the holding bracket, the vibration insulation device comprisinga support head which secures the motor drive against rotation,a radial damping member of a vibration-damping, flexible material which positively engages the support head in the direction of rotation; anda mounting head which is non-rotatably mounted on the holding bracket and positively engages the radial damping member in the direction of rotation.

The invention provides a shearing box, comprising at least two bases arranged on different vibrating tables, and laminated box bodies which are placed on the bases and are formed by overlapping framesprovided with openings at the side edges; every two adjacent bases are connected with each other by means of a bearing plate, one end of the bearing plate is fixed, and the other end of the bearing plate is movable; every two adjacent frames, which are positioned on the different laminated box bodies and are arranged on the same horizontal plane, are connected with each other by means of a universal coupling; openings of the adjacent laminated box bodies are connected with each other by means of a baffle plate so as to form a communicated container; all the laminated box bodies are respectively provided with limiting components, so that the soil in the shearing box can be subjected to different excitation; furthermore, the seismic ground motions of the bases are relatively independent, but can be mutually propagated; the laminated box bodies are communicated with one another, and the soil can be placed at the communicating parts; the vibration is propagated through the soil medium, sothat the constitutive property that the frame structure of the shearing box is perpendicular to the vibration direction is met; furthermore, the structure can rotate along multiple directions, the real situation of the interaction between the soil and the underground structure under multi-point excitation is simulated, the experiment is accurate.

The invention provides a dehydration control method of a drum washing machine and the drum washing machine. The method comprises the following steps that at least two low-speed eccentric detection stages and the rotating speed of motors corresponding to each low-speed eccentric detection stage are set, and the rotating speeds of the motors corresponding to different low-speed eccentric detection stages are different; after a dehydration program is started, at each low-speed eccentric detection stage, the following operations are executed: when the rotating speed of the motor reaches the current rotating speed corresponding to the current low-speed eccentric detection stage, the motor is controlled to perform constant-speed operation for a set duration at the current rotating speed; a current eccentric parameter is obtained; and according to a located value interval of the current eccentric parameter, the current eccentric treatment is performed. The dehydration control method and the drum washing machine adopting the scheme have the advantage that the vibration of the washing machine can be more reliably enabled to be in a controlled range during high-speed dehydration.

The invention discloses a roller bearing vibration measuring device. The roller bearing vibration measuring device comprises a mandrel for mounting a measured bearing, a sensor and a radial loading mechanism, wherein the sensor is positioned above the mandrel; a measuring head of the sensor is in contact with the outer surface of the top of the measured bearing on the mandrel to form a contact C;the radial loading mechanism comprises a first radial loading assembly and a second radial loading assembly which are arranged below the mandrel respectively. The roller bearing vibration measuring device is reasonable in structure; the load used during measurement is the same as that borne by the bearing during actual use, so that a measurement error is reduced, and that vibration and noises of the bearing can meet the using requirements of a customer in the mounting and using processes is guaranteed.

A diaphragm, including: a metal dome, a non-metallic diaphragm portion, and a flexible rim. The non-metallic diaphragm portion is bonded to a metal dome outer periphery, and a non-metallic diaphragm portion outer periphery extends corresponding to a convex direction of the metal dome and expands radially away from the metal dome. The flexible rim is bonded to the non-metallic diaphragm portion outer periphery. The diaphragm of the present application adopts the combination of the metal dome, the non-metallic diaphragm portion, and the flexible rim, the overall rigidity of the diaphragm is enhanced, and the internal damping property of the diaphragm and the compliance of the vibration of the diaphragm can be adjusted, which can effectively reduce segmentation vibration of the diaphragm during high-frequency vibration and reduce the segmentation distortion of the diaphragm at high frequencies, thereby extending the bandwidth of the diaphragm.

The invention relates to a preparation method of a hollow fiber nanofiltration membrane. The method is characterized by including the steps of spinning solution preparation, spinning, curing and post-treatment pore retention. The spinning solution preparation includes: adding polyethersulfone, a pore-making agent and an organic solvent into a dissolving tank, utilizing a crusher for forward rotating stirring, and stopping the action for 30-60s, then conducting reverse rotating stirring, and stopping the action for 30s, conducting mixing crushing stirring for full dissolution until a spinning solution is obtained; the spinning includes: subjecting the spinning solution to the bubble removal pretreatment by a vacuum defoaming device; the curing includes: passing a primary membrane of the hollow fiber nanofiltration membrane through gas bath with a casting temperature of 30-50DEG C and a relative humidity of casting of 60-80% in order for curing pre-evaporation, then letting the primary membrane subjected to gas bath curing enter coagulating bath in a 15-40% dimethyl sulfoxide aqueous solution for stretching curing under a drafting godet stretching ratio of 1.9-2.3 times; and the post-treatment pore retention includes: conducting steam washing and pore retention ultrasonic cleaning on the stretch cured hollow fiber nanofiltration membrane in order, and finally performing air-drying, thus obtaining the hollow fiber nanofiltration membrane.

The invention discloses a small-sized combustion engine power rock drill, which comprises a combustion engine, a reduction gearbox, an output master lever and a drill bit, wherein the power output end of the combustion engine is provided with a spline plate; the spline plate is connected with a spline shaft at the rear end of the reduction gearbox in the manner of meshing; the front end of the output master lever is provided with the drill bit; the rear end of the output master lever is connected with an output shaft of the reduction gearbox; the combustion engine and the reduction gearbox are arranged on a towing bracket; the towing bracket is movably linked with a channel steel stand; a closed loop chain is connected onto the channel steel stand through a chain wheel shaft; the towing bracket moves front and back on the channel steel stand through the closed loop chain; one end of the chain wheel shaft is provided with a manual stress application lever feed mechanism; the shifting of the towing bracket is finished in the manner that the chain wheel shaft is rotated by the manual stress application lever feed mechanism to drive the closed loop chain; the chain wheel shaft is provided with a stopping gear; and the channel steel stand is provided with movable stopping claw. The small-sized combustion engine power rock drill disclosed by the invention has the advantages of simple structure, convenience in installation, use and maintenance, high rotate speed, low energy consumption and high stationarity and can be used in districts without electricity.