48results about How to "Reduce assembly requirements" patented technology

The utility model provides a mattress frame taking mechanism, and belongs to the technical field of machinery. The problem that an existing mechanism is large in design difficulty is solved. The mattress frame taking mechanism comprises a rack and a grabbing assembly used for grabbing a frame. The rack is provided with a longitudinal beam and a lifting assembly used for driving the longitudinal beam to ascend and descend. A supporting frame is arranged between the longitudinal beam and the material grabbing assembly, and the material grabbing assembly is arranged on the supporting frame. The supporting frame is hinged to the lower end of the longitudinal beam, a driving mechanism enabling the supporting frame to swing in a reciprocating mode is arranged on the longitudinal beam, and the swing angle of the supporting frame ranges from 0 degree to 90 degrees so that the frame can be switched from the vertical state to the horizontal state. The mattress frame taking mechanism is low in design difficulty.

The embodiment of the invention discloses a traveling wave tube high-frequency assembly and an assembling method thereof, the traveling wave tube high-frequency assembly comprises a traveling wave tube high-frequency assembly, the high-frequency assembly comprises a composite tube shell and an all-metal slow wave structure arranged in the composite tube shell, the composite tube shell comprises an electron gun welding disc, a pole shoe, a spacer ring and a collector welding disc, and the electron gun welding disc, the pole shoe and the spacer ring are brazed together. The all-metal slow-wave structure is composed of a plurality of radial sub-cavities, and the radial sub-cavities are fixed in the composite tube shell through high-temperature diffusion welding. The high-frequency assembly does not need to use a thin-wall tube shell, is simple to assemble, can reduce the inner diameter of a magnetic system, increases bunching current, and further increases the output power under the condition that the voltage is not changed. The composite tube shell and the all-metal slow wave structure are matched through a circle, and the machining precision error can be 0.08 mm. The multiple radial sub-cavities can be fixed in the composite tube shell only through high-temperature diffusion welding, the technological process is simple, the assembly efficiency and precision are high, and the problem that the matching degree becomes poor due to the fact that welding flux flows into the slow-wave structure is solved.

The invention discloses a binocular parallelism error measuring device and method for a microscope. The binocular parallelism error measuring device of the microscope comprises a base and a first measuring assembly and a second measuring assembly which are located on the base, the first measuring assembly comprises a first detector, a first lens cone and a first objective lens which are connected in sequence, and the second measuring assembly comprises a second detector, a second lens cone and a second objective lens which are connected in sequence. The first objective lens and the second objective lens are used for respectively aligning with an ocular lens of a binocular microscope to be detected, and the first detector and the second detector are used for respectively displaying respective centers and received cross images of the binocular microscope on a display device.

The utility model discloses a liquid storage device, an atomizer and electronic atomization equipment, the liquid storage device comprises a shell, a base and a sealing cover, a liquid storage cavity is formed in the shell, and an opening is formed in the shell and communicated with the liquid storage cavity; the base is made of a PP material, the base is inserted into the opening and is in interference fit with the shell to seal the opening, a liquid injection hole is formed in the base, and the liquid injection hole penetrates through the base to communicate the liquid storage cavity with the outside of the shell; the sealing cover is detachably arranged on the base, and a sealing plug is arranged on the sealing cover in a protruding mode and can be inserted into the liquid injection hole to seal the liquid injection hole. According to the liquid storage device, the base is made of the PP material with the deformation resistance better than that of the silica gel material, the base is in interference fit with the shell, the sealing performance of the liquid storage device can be guaranteed without independently arranging a sealing gasket or a sealing ring on the base, the structure is simplified, mechanical assembly or manual assembly can be directly adopted, the assembly requirement and cost are reduced, and the size of the atomizer can be reduced.

According to the rotor rotating device and the aircraft, the driving device of the rotor rotating device can drive the rotor to rotate so as to switch the position of the rotor, and switching of the rotor between different working states is achieved; the locking device of the rotor wing rotating device can lock the rotating piece and the fixed piece so as to lock the position of the rotor wing, so that it is guaranteed that the rotor wing can maintain different working states and can be kept stable in the different working states, and safety and reliability are improved; the rotating piece and the fixed piece can be linked by different locking pieces of the locking device, that is, the rotating piece and the fixed piece can be locked through two independent structures, the service life of the locking device is long, the assembling requirement between the locking device and the driving device is low, and the assembling efficiency is high. And the requirements of a user on low assembly difficulty and a simple connection structure of the rotor rotating structure can be met.

The utility model discloses an air conditioner and a display lamp panel assembling structure thereof. The display lamp panel assembling structure comprises a panel and a display lamp panel assembly. An opening is formed in the panel; the display lamp panel assembly comprises a lamp holder, a light-emitting part and a lamp cover. An opening is formed in the lamp holder, the luminous body is arranged in the opening of the lamp holder, and the lamp cover is mounted at the opening of the lamp holder; the lamp cover is made of a transparent material; a display part protrudes on the lamp cover, and the outline of the display part is matched with the open hole; the lamp holder is connected with the back of the panel, the panel and the lamp holder clamp the lamp cover, and the display portion of the lamp cover is embedded into the opening of the panel. According to the arrangement, a thinning area does not need to be designed on the panel, the bulge risk of the display area is avoided, the panel is smoother, and the whole panel is more attractive; and the display lamp panel assembly and the panel are positioned through a plurality of buckles and are fixedly connected through screws, so that the assembly requirement of the panel and the display lamp panel assembly is lower.

The utility model provides a structured light emitting device and a structured light transmitting and receiving system. The structured light emitting device comprises a first shell, a second shell and a light source, the light source array is arranged at the lower end of the cavity of the first shell; the super lens is arranged at the upper end of the cavity of the first shell; the super lens comprises a substrate and a micro-nano structure, a structural surface of the micro-nano structure is arranged on the substrate, and a protective layer is also arranged on the substrate; the height of the micro-nano structure relative to the structural surface is equal to or smaller than the height of the protective layer relative to the structural surface; the super lens is parallel to the light source array; after light emitted by the light source array enters the super lens, the light is copied into structured light by the super lens. The structured light emitting device provided by the utility model is low in assembly difficulty.

The present invention discloses an integrated electromagnetic head structure, which relates to the field of automobile transmission hydraulic electromagnetic valves, and aims to solve the problem that the traditional electromagnetic head structure has a large number of parts, high assembly requirements, and requires complex part shapes to maintain the reverse magnetic path. The key points of its technical solution include a shell, a stopper iron is arranged in the shell, a sliding hole is opened in the middle of the stopper iron, and an armature push rod is arranged in the sliding hole; the side wall of the armature push rod is opened with a stepped ring groove to make it dumbbell-shaped. The present invention simplifies the electromagnetic head structure, and integrates the traditional armature, valve core push rod and pole shoe into a stepped core part, namely the armature push rod, so as to reduce the number of parts. The armature push rod is made of the same material as the armature, plays the role of the armature, can move directly, no longer requires a complex reverse magnetic path, and greatly reduces the assembly requirements.

The invention relates to the field of galvanic pile production equipment, in particular to a torsion-resistant tool for high-precision assembly on a galvanic pile production line. The stacked fixed backer is fixedly arranged on the top surface of the reference bottom plate; the stacking movable backer is arranged on the top surface of the reference bottom plate and is opposite to the stacking fixed backer; the adjusting mechanism is fixedly installed on the reference bottom plate and provided with an action end, and the action end is connected to the stacking movable backer. The adjusting mechanism can drive the stacking movable backer to linearly move towards or away from the stacking fixed backer. According to the tool, the stacking efficiency is improved while the stacking precision of the single cells of the electric pile is ensured; an effective anti-torsion effect is achieved for tightening an anti-disassembly nut at a special position of a galvanic pile, all parts do not interfere with one another while playing respective roles in a limited and narrow space due to the overall design, the structure is simple, the machining requirement and the assembly requirement are low, the cost is saved, and the labor intensity of workers is reduced; the whole structure is clean and pollution-free, and the environment is effectively protected.

This invention relates to the field of welding technology, and provides a through-type friction stir welding apparatus and method suitable for different plate thicknesses. The through-type friction stir welding apparatus includes a long needle stirring tool, a backing block, a limiting platform, a clamp, a positioning platform, and a worktable. The long needle stirring tool is mounted on a friction stir welding machine. The backing block is disposed on a limiting groove on the limiting platform. The positioning platform is disposed on both sides of the limiting platform, and the clamp is disposed on the positioning platform. This invention utilizes a through-type friction stir welding technology with a long needle stirring tool and a backing block, which can completely eliminate the potential risks of incomplete penetration and weak bonding at the weld root. By using a backing block made of the same material as the workpiece being welded, no material loss occurs during the through-type welding process, thus eliminating defects at the start of the through-type friction stir weld.

The CMT bottoming laser-arc hybrid welding process comprises the steps that the joint of a to-be-welded base material is polished to remove oxide skin, the to-be-welded base material is cleaned up, and the to-be-welded base material is fixed to a workbench through a clamp; a CMT welding gun is fixed to the robot, the angle between a welding wire used by the CMT welding gun and the upper surface of the to-be-welded base metal ranges from 25 degrees to 70 degrees, and CMT backing welding is conducted; the MIG welding gun is fixed to the robot, the wire feeding end of the MIG welding gun is arranged at the position 1-3 mm away from a laser beam emitted by the laser device in front, the laser beam is perpendicular to the welding direction, the angle between a welding wire used by the MIG welding gun and the upper surface of the to-be-welded base metal ranges from 25 degrees to 70 degrees, and laser welding and MIG electric arc welding composite welding is conducted. The composite welding process has the advantages of being large in welding penetration depth, high in welding speed, small in workpiece deformation, low in assembly requirement, high in molten pool bridging capacity, high in welding quality, good in welding seam performance, easy to achieve automatic welding and the like.

The present invention discloses a punching device for a pattern machine, the main points of which are: it includes an upper punch assembly and a lower punch assembly. The upper punch assembly includes a machine head seat, a driving device, a guide device, a punch seat and a punch needle. The driving device is arranged on the machine head seat, and the driving device drives the punch seat to move up and down along a straight line through the guide device. The punch needle is detachably fixedly connected to the punch seat and extends downward. The lower punch assembly includes a lower die knife. The lower die knife is arranged in the sewing table of the machine head of the pattern machine, and its upper surface is flush with the upper surface of the sewing table. The punch needle hole is provided with a cylindrical section, and the punch needle extends into the punch needle hole to form a shear structure with the hole wall.

This utility model discloses an adjustable connecting plate. The main body of the connecting plate is connected to the sliding structure on both sides of the cabinet through the first connecting part and the second connecting part on both sides. The extension length of the first connecting part and the second connecting part can be adjusted by the adjustment structure. After the first connecting plate and the second connecting plate are fastened together, they form a sliding groove to guide the sliding of the first rack and the second rack. The first connecting plate and the second connecting plate can be clamped and locked by tightening the fastening screw, thereby achieving the purpose of fixing the connecting parts on both sides. The main body of the connecting plate can be extended and adjusted independently according to the size of the cabinet without on-site cutting, which reduces the requirements for assembly and simplifies the on-site installation process.

The invention discloses a high-circulation-efficiency heat insulation type fireproof and smoke-proof valve which comprises an outer frame and a locking assembly, a signal box is fixed to the outer frame through the locking assembly, blades are fixed in the outer frame through fasteners, and each blade comprises a blade frame, a blade fan, a transmission main shaft and an auxiliary shaft. The transmission main shaft and the auxiliary shaft are arranged on the two sides of the outer frame, the transmission main shaft is locked and fixed through a locking half-moon plate matched with a screw, the transmission main shaft penetrates through the action executing mechanism, and the action executing mechanism is arranged on the outer frame. The valve has the beneficial effects that the effective ventilation area is obviously increased when the blades are in a full-open state, the heat deformation resistance is improved, and the sealing effect of the valve cannot be influenced in a high-temperature environment; the assembly requirement is low, debugging is easy, after the connector is connected with the outer frame, later disassembly and error correction are not affected, disassembly and assembly are fast and convenient, the outer frame independently bears the interface installation function, and installation is fast.

The present application provides an operation control method, a compressed air heat exchange system and a readable storage medium, wherein the compressed air heat exchange system comprises: a processor; a heat exchanger, comprising an inner circulation flow path and an outer circulation flow path arranged in parallel, wherein both ends of the outer circulation flow path are connected to the outside; a fan, arranged on the outer circulation flow path; a pressurization expansion assembly, electrically connected to the processor and connected to the inner circulation flow path; an air supply flow path, connected to the pressurization expansion assembly, for supplying air to the room; an air guide assembly, electrically connected to the processor, the air guide assembly comprising a first regulating part and a second regulating part arranged at the outlet end of the air supply flow path, and the processor is used to execute computer instructions to perform the following steps: controlling the first regulating part to be away from the second regulating part to open the outlet end, or the first regulating part and the second regulating part to adapt to close the outlet end. By implementing this technical solution, the arrangement of the air supply components in the compressed air heat exchange system on the indoor side can be simplified, thereby improving the aesthetics of the indoor air outlet.

The utility model belongs to the technical field of pocket opening machines, and relates to a cutting and opening device of a pocket opening machine, which comprises a sewing machine, a base and a bedplate, a rotating shuttle seat is arranged on the base corresponding to a machine head of the sewing machine, a rotating shuttle cover plate is arranged on the rotating shuttle seat, the rotating shuttle seat is positioned below the bedplate, the rotating shuttle cover plate and the bedplate are positioned on the same plane, and the bedplate is positioned below the sewing machine. A circular cutter assembly is arranged on the rotating shuttle seat in a sliding mode, the circular cutter assembly comprises a cutting motor and a circular cutter driven by the cutting motor to rotate, the rotating shuttle cover plate is provided with an opening groove for the circular cutter to stretch out, a roller matched with the circular cutter is arranged on the machine head in a sliding mode, and the roller compresses cloth on the platen when moving downwards. The cutting and opening device of the bag opening machine has the advantages of being simple in structure, smooth in cutting and low in assembly requirement.

The utility model relates to a head shaking structure and a fan. The head shaking structure comprises a support, a base and a head shaking motor. The base and the support are rotatably connected around a rotating shaft. The oscillating motor is arranged on the support, and an output shaft of the oscillating motor is arranged along the rotating shaft and matched with the base in a rotation stopping mode. According to the head shaking structure, the head shaking motor is arranged on the support, the output shaft is matched with the base in a rotation stopping mode, and the support is rotationally connected with the base. Therefore, after the fan is started, the oscillating motor can drive the support and the base to rotate relatively, and then oscillating motion of the fan is achieved. Therefore, the oscillating structure can realize that the oscillating motor directly drives the fan to oscillate without a complicated transmission mechanism, the structure is simpler, the processing and assembling requirements are lower, the rotation of the fan is more stable, and abnormal sound is not easy to generate.

The utility model is suitable for the technical field of workpiece cleaning, and provides a pass-type ultrasonic cleaning device which comprises a rack and further comprises a conveying chain. The tool is flexibly connected with the conveying chain; the water collecting tank is located below the tool; an upper ultrasonic cavity; an O-shaped sealing strip; the upper ultrasonic groove is fixedly arranged at the bottom of the upper ultrasonic cavity, and an O-shaped sealing strip is embedded in the upper ultrasonic groove; the lifting structure is used for driving the upper ultrasonic tank to ascend or descend; an O-shaped sealing strip is embedded in the lower ultrasonic groove; the jacking structure is used for driving the lower ultrasonic tank to ascend or descend; and the cleaning structure is used for cleaning the workpiece. According to the utility model, the tool and the upper ultrasonic groove can float, so that the assembly and manufacturing precision requirements are not high; the sealing between the lower ultrasonic tank and the tool and the sealing between the tool and the upper ultrasonic tank are floating type pressing, so that the repeatability and the stability of the device are ensured; and after each time of ultrasonic cleaning, all cleaned dirt can be discharged, so that the cleaning effect is improved.

The utility model discloses a firearm sight structure capable of adjusting the width of a notch, which is suitable for different requirements and wide in application range. Comprising a sight seat, a square groove is formed in the sight seat, an adjusting rod is arranged between the two side walls of the square groove of the sight seat, cross threads are arranged in the middle of the adjusting rod, a left sight and a right sight are arranged in the square groove of the sight seat, and leaf springs are arranged between the bottom wall of the square groove of the sight seat and the bottoms of the left sight and the right sight. The left rear sight and the right rear sight are matched with crossed threads on the adjusting rod respectively, the screwing directions of the threads on the left rear sight and the right rear sight are opposite, the two ends of the adjusting rod are both in clearance fit with the rear sight seats, and the portions, corresponding to the head of the adjusting rod, in the rear sight seats are provided with top heads and top head springs, and the top heads are perpendicular to the adjusting rod. A plurality of arc-shaped grooves are evenly formed in the cylindrical face of the head of the adjusting rod in the circumferential direction, the ejector heads are ejected into one groove under the action of the ejector head spring, and circumferential positioning of the adjusting rod is achieved.

This utility model relates to the technical field of cotton candy equipment, specifically disclosing an integrated drive device for a motor and a furnace head main shaft. The device includes a support base on which a brushless motor is mounted. A hollow motor shaft is installed inside the brushless motor, and a sugar feeding pipe is installed inside the motor shaft. A furnace head is mounted at the upper end of the motor shaft and the sugar feeding pipe, enabling the motor shaft, sugar feeding pipe, and furnace head to rotate synchronously. This integrated drive device integrates the motor shaft of the brushless motor with the furnace head, eliminating the need for traditional drive wheels, driven wheels, and belt drive structures. By directly connecting the motor shaft of the brushless motor to the furnace head, the size of the furnace head is reduced, resulting in a simpler overall structure, lower maintenance costs, and simpler assembly requirements.

The invention discloses a stainless steel composite plate welding method considering welding deformation control and welding efficiency. The stainless steel composite plate welding method comprises the following steps that (1) a stainless steel composite plate to be welded comprises a base layer and a composite layer; the base layer is carbon steel and the composite layer is stainless steel; (2) the two stainless steel composite plates to be welded are subjected to positioned welding assembly, the positioned welding assembly gap is controlled to be (0.2-0.3) b2 mm, and b2 is the thickness of the base layer; and (3) the stainless steel composite plate is welded, stainless steel composite plate welding seams comprise a base layer carbon steel welding seam, a transition layer stainless steel welding seam and a composite layer stainless steel welding seam, and each layer of welding seam only has one welding bead. The comprehensive welding quality (good corrosion resistance and mechanical property), welding deformation control, welding efficiency and cost of the stainless steel composite plate are considered; the method is suitable for connection of medium-thickness single-face stainless steel composite plates applied to the fields of petroleum, chemical engineering, light industry, ocean engineering, nuclear industry and the like.

A high-voltage disconnector is connected between the isolation intervals of at least one phase busbar, and includes a contact assembly, a moving assembly and a traction assembly. The contact assembly is connected to the traction assembly, and the contact assembly is slidably matched with the busbar through the moving assembly. The traction assembly includes a drone, and the drone can drive the contact assembly to reciprocate between the isolation intervals along the axis direction of the busbar to connect or disconnect the isolation intervals. A high-voltage disconnector of the present invention does not have a complex operating mechanism and transmission mechanism. The contact assembly performs linear reciprocating motion under the cooperation of the moving assembly and the traction assembly. The drone is used to drive the opening and closing of the contact assembly, and the insulator can be further omitted, making its structure and the coordination between the various mechanisms simple, reducing the requirements for assembly accuracy and degree of coordination, and the overall space occupied is small.

The invention discloses a numerical control tool grinding machine spindle grinding head mounting precision adjusting method, which is characterized in that when a spindle grinding head is mounted, the axis of the spindle grinding head often deviates from the axis of a rotary table and the perpendicularity of the axis of the spindle grinding head and the axis of the rotary table is out of tolerance due to the influence of part machining and assembly precision; at the moment, the deviation distance and perpendicularity can be adjusted by adjusting a jackscrew installed on the connecting disc. The method comprises an adjusting method for the deviation distance between the connecting disc connected between the rotating table and the main shaft grinding head and the axis of the rotating table and an adjusting method for the perpendicularity between the axis of the main shaft grinding head and the axis of the rotating table. According to the method, the mounting precision of the main shaft grinding head can be conveniently and quickly adjusted, the machining and assembling requirements of spare and accessory parts are greatly reduced, and the mounting precision problem of the main shaft grinding head is well solved.

The novel fascia gun comprises a machine shell, a driving motor, a transmission assembly and a massage assembly, the transmission assembly comprises an eccentric wheel, a connecting rod and a sliding bearing, a motor shaft of the driving motor is connected with the eccentric wheel to drive the eccentric wheel to rotate, and an eccentric shaft on the eccentric wheel is connected with the connecting rod; the connecting rod is arranged in the sliding bearing, a pin groove is formed in the position, close to the front end, of the connecting rod, an upper pin hole and a lower pin hole are formed in the sliding bearing, pins are led into the pin groove and the pin holes to be fixedly connected, and first silicon rubber cases are arranged in the pin holes and the pin groove. A pin hole is formed in the sliding bearing, a first silicon rubber sleeve is arranged at the outer position of the pin hole and wraps the pin hole, the first silicon rubber sleeve is connected with the inner wall of the sliding bearing in an attached mode, the pin and the silicon rubber sleeve are assembled in a matched mode, the movement direction can be adjusted in a self-adaptive mode, meanwhile, the swing angle generated when a driving motor drives the sliding bearing to move is reduced, and then noise is lowered.

The utility model discloses a treatment head and a therapeutic apparatus, the treatment head comprises a shell, a guide shaft, a shaft sleeve and a transduction assembly, the guide shaft, the shaft sleeve and the transduction assembly are all located in the shell, the guide shaft is connected with the shell, the shaft sleeve is slidably connected with the guide shaft, and the shaft sleeve is suitable for moving in a first direction; the transduction assembly comprises a support and a transducer, the shaft sleeve is connected with the support in an abutting mode, and the support can move in the first direction through the shaft sleeve and output ultrasonic energy through the transducer. According to the invention, the assemblability of the support and the shaft sleeve can be improved, the shaking amount of the support is reduced, and the treatment effect of the treatment head is improved.

The utility model relates to the technical field of electronic products, and discloses an electronic equipment accessory, which comprises a shell, a circuit board assembly and a heat dissipation component, and is characterized in that the shell is provided with an inner wall structure forming an accommodating cavity; the circuit board assembly is arranged in the accommodating cavity, and the circuit board assembly is provided with a first fixing structure; the heat dissipation component is arranged between the circuit board assembly and the inner wall of the shell, the heat dissipation component is provided with a second fixing structure matched with the first fixing structure, and detachable fixed connection between the heat dissipation component and the circuit board assembly is achieved through insertion matching of the first fixing structure and the second fixing structure. Compared with the prior art in which the radiating fins and the circuit board are welded and fixed through tin soldering, the plug-in operation is more convenient, the assembly process is simplified, the assembly requirement is reduced, the assembly efficiency and the product production efficiency can be improved, meanwhile, tin materials are saved, and the production cost is reduced. Moreover, during later maintenance, the operation of desoldering and tin melting is not needed, so that the maintenance efficiency can be improved, and the circuit board assembly is not easy to damage.

The utility model discloses a vacuum tank cover structure which comprises a tank cover and a vacuumizing assembly, an exhaust containing cavity with an opening in the upper end is formed in the tank cover, an exhaust channel used for exhausting is arranged on the bottom face of the exhaust containing cavity, a first one-way valve is installed on the exhaust channel, and the vacuumizing assembly is arranged in the exhaust containing cavity in an up-down moving mode. An exhaust flow channel is integrated in the vacuumizing assembly, the input end of the exhaust flow channel is communicated with the exhaust containing cavity, a second one-way valve is arranged in the exhaust flow channel, an exhaust port communicated with the exhaust flow channel is formed in the vacuumizing assembly, and a sealing ring tightly attached to the inner side wall of the exhaust containing cavity is fixedly arranged on the vacuumizing assembly. Through the arrangement of the double one-way valves, the problem that in the prior art, exhaust is unstable due to the fact that exhaust is conducted through a movable sealing ring can be solved.

The invention discloses a connection structure of a plunger and a crosshead, comprising a plunger, a crosshead, an upper compensation block and a lower compensation block, wherein the lower end of the plunger has a disc-shaped structure, the upper part of the crosshead has a compensation cavity, the upper wall of the compensation cavity has a first through hole, the plunger passes through the first through hole, the upper compensation block, the lower compensation block and the disc-shaped structure are located in the compensation cavity, the upper compensation block is located on the upper side of the disc-shaped structure, the lower compensation block is located on the lower side of the disc-shaped structure, a radial gap is provided between the outer side wall of the plunger and the inner side wall of the first through hole, an axial gap is provided between the upper compensation block and the upper wall of the compensation cavity, a radial gap is provided between the upper compensation block and the side wall in the compensation cavity, a radial gap is provided between the lower compensation block and the side wall in the compensation cavity, and a radial gap is provided between the disc-shaped structure and the side wall in the compensation cavity. The plunger can be radially displaced and can also be rotated in the compensation cavity, and radial compensation and angle compensation can be realized simultaneously, so that the plunger can be self-adjusted in time to ensure smooth reciprocating motion.