63 results about "Spherical design" patented technology

The invention discloses a portable foldable spherical unmanned aerial vehicle. The scheme of the portable foldable spherical unmanned aerial vehicle is provided in order to solve the problems that a traditional multi-rotor unmanned aerial vehicle cannot be folded and is large in occupied space and the like. The unmanned aerial vehicle has two states which are the folded state and the unfolded state, and the two states can be switched. By the adoption of the technical scheme, compared with the prior art, the portable foldable spherical unmanned aerial vehicle has the following technical beneficial effects that due to the unique foldable spherical design, certain art elements are introduced into the unmanned aerial vehicle, and the unmanned aerial vehicle has certain artistic ornamental value; exquisite self-locking structural design guarantees that the unmanned aerial vehicle is not heavier on the basis that the positions of vehicle arms and a vehicle body are relatively fixed when the unmanned aerial vehicle flies; the unique folding structural design and spherical structural design are adopted, so that the portability of the unmanned aerial vehicle is greatly improved, and the unmanned aerial vehicle can be conveniently carried by a user outside and carried by a solider; and when in the unfolded state, the unmanned aerial vehicle is in a four-rotor mode, flight is stable, and operation is easy.

The invention discloses a multifunctional spherical mixing, grinding and drying all-in-one machine, comprising a shell, a rotating hoop quick-opening device, a stirring paddle, a crushing cutter, a heating system, a dedusting filter, a CIP cleaning system, a charging valve, a discharging valve and a dry airtight sealing system; the shell is a spherical body; the stirring paddle and crushing cutter are arranged in the shell divided into an upper half sphere and a lower half sphere; the upper half sphere is provided with the CIP cleaning system, a blowback sight glass port, a speed reducer, the charging valve, the temperature sensor, the dry airtight sealing system and the dedusting filter; a motor is arranged at one side of the dedusting filter; the speed reducer is provided with a rotary joint; the lower half sphere is provided with a vacuum sampling valve. Materials are dried and mixed without dead angles due to the spherical design; the crushing cutter is added to prevent the product from forming hard blocks during drying and prevent water content from being locked in the product, the stirring paddle is obliquely mounted to conveniently overturn materials, and stirring has no dead angle; the sphere body is provided with the rotating hoop quick opening device and has self locking function, thus facilitating quick checking.

The invention relates to a hydraulic transformer with a safety device. The hydraulic transformer uses a cylinder block type plunger pump as design basis, and changes the position of a plunger chamber corresponding to three oil chambers in the oil absorption and drainage processes by a valve plate, thus changing notch flow to compensate flow difference between a high pressure oil end and a low pressure oil end, and ultimately realizing self-rotary motion and energy output. The novel hydraulic transformer and a safety valve assembly thereof are designed; the novel hydraulic transformer is of spherical design of a cylinder block and the valve plate, and central cylinder body shaft supporting and hydrostatic bearing valve plate design, which greatly reduces volume and weight of the hydraulic transformer, solves the problem of oil throttling loss between the valve plate and a rear end cover, expands voltage regulation percentage range of the hydraulic transformer, and can cause the hydraulic transformer to rotate within a wide angle range in both normal and reverse directions, thus maximizing voltage regulation functions, recovery load functions and energy-saving functions of the hydraulic transformers, and reducing noises of the hydraulic transformers.

The invention discloses an antenna convenient to retract for 5G Internet of Vehicles. The antenna comprises a mounting plate, a protective shell, an antenna body and an auxiliary plate, wherein the protective shell is arranged above the mounting plate, the antenna main body is connected to the upper part of the protective shell in a nesting manner, and the auxiliary plate is bonded to the lower part of the antenna body, a baffle is arranged below the auxiliary plate and located in the protective shell, the outer end of the baffle is in key connection with a connecting shaft, the connecting shaft is installed in the protective shell through a bearing, the surface of the connecting shaft is provided with a torsion spring, and the outer side of the connecting shaft is provided with a placement groove. The antenna convenient to retract for 5G Internet of Vehicles is provided with supporting plates and a connecting block, a connecting column can rotate to a certain extent under the action of the connecting block in spherical design and can be reset through the cooperation of the supporting plates and reset springs after the rotation, so that the antenna main body or the protective shellcan rotate to a certain extent when being impacted by the outside, and the impact force is buffered.

A method for designing nonspherical lens includes setting dioptre and refractive index as well as diameter of nonspherical lens, applying spherical design to design two curvature radius for nonspherical lens to let it realize set dioptre, using two said curvature radius to make visual field distortion to be minimum value and using lens nonspherical design formula to design the first nonspherical surface and the second nonspherical surface.

The invention relates to a prime lens used for an infrared camera. The prime lens comprises a first single negative non-spherical lens, a second single negative spherical lens and a third single positive spherical lens. The first single negative non-spherical lens is of a ten-order-coefficient non-spherical design. The second single negative spherical lens is made of sulfur infrared glass. The prime lens used for the infrared camera is simple in structure and convenient to manufacture, meanwhile, improves the imaging effect and reduces manufacturing cost.

A mold with which a molded product in a desired shape with an aspherical curved surface is molded can be designed with high precision by correcting shape deformation of the molded product molded from the mold.A mold 10 in which use surfaces 16 of an upper mold 11 and a lower mold 12 are formed to be design curved surfaces of the optical lens in a spherical shape is prepared. A curved surface shape of the optical lens molded from the mold is measured, a measured value is approximated by an equation (1) which is an equation of an aspherical surface and a curved surface of the molded optical lens is specified as an aspherical surface. Information corresponding to an error between the curved surface of the optical lens specified by the equation of the aspherical surface and the above-described design curved surface is compiled into database for each of characteristics of the optical lens as correction information for molding the optical lens of which curved surface is in the spherical shape. By using the correction information compiled into database, design values of the use surfaces in the upper mold and the lower mold of the mold with which the optical lens of which curved surface in the aspherical shape is molded are corrected to design them.[Mathematical⁢⁢Expression⁢⁢10]Z=C⁢⁢ρ21+1-(1+K)⁢C2⁢ρ2+∑i=2n⁢A2⁢i⁢ρ2⁢i.(1)

The invention relates to an athermal lens, which adopts a two-piece spherical design. A piece of quartz glass with acid resistance and extremely small thermal expansion coefficient is adopted as a first piece of lens, both the first and the second surfaces of the first piece of lens are spherical surfaces, and a diaphragm is located on the first surface; fluorite is adopted as a second piece of lens, and both surfaces of the lens are spherical surfaces. The principle of the athermal lens is as follows: when being irradiated by laser, a lens is heated to expand, so that the focal length is increased, and as a result, the optical performance is affected; at the moment, the two lenses made of the different materials are used, the refractive index of the two materials can be affected by temperature to decrease; and by scientific calculation, the focal length decreased by the change of the refractive index can counteract the focal length increased by thermal deformation, so that the original focal length can be kept unchanged.

Toggles are disclosed for toggle connections of conveyor pans of a chain scraper conveyor or conveyor troughs of a mining machine guide. In providing a toggle and a toggle connection, with which high axial forces can be transmitted while, at the same time, maintaining high angular mobility of the pans and troughs, shoulder areas of the toggle are designed so as to be spherical. Because of the spherical design of the shoulder areas, the vertical mobility of adjoining conveyor pans is improved while at the same time the transmission of axial tensile forces to the toggle heads is optimized.

The invention discloses a garbage incinerator capable of automatic deslagging. The garbage incinerator capable of automatic deslagging comprises a main machine body. A crushing cavity is formed in themain machine body. The bottom of the crushing cavity is of a spherical design. A crushing mechanism is arranged in the crushing cavity. The crushing mechanism comprises first crushing blades and second crushing blades. The first crushing blades and the second crushing blades cooperate with each other to crush garbage. A driven cavity is formed in the top of the crushing cavity. A transmission cavity is formed in the right side of the crushing cavity. A power mechanism is arranged in the transmission cavity. An incineration cavity is formed in the bottom of the transmission cavity. An incineration mechanism is arranged in the incineration cavity. According to the garbage incinerator capable of automatic deslagging, the crushing mechanism and the incineration mechanism are integrated into one; functionality of the equipment is increased; in addition, the garbage is turned over through an overturning rod so that the garbage is fully burned; and through sliding of a pushing block, the garbage is extruded and convenient to pack.

The invention relates to a large-image-plane, high-resolution and low-distortion optical lens. An optical system is composed of a first lens assembly, a diaphragm, a second lens assembly and an imaging plane from left to right in the light incidence direction. The focal power of the first lens assembly is positive, and the focal power of the second lens assembly is positive. Spherical design is used in the optical lens, the processing property is good, and the material cost is low. The large-image-plane, high-resolution and low-distortion optical lens can be widely applied to the fields of industrial measuring detection, intelligent traffics and the like.

The invention discloses a movable light-emitting diode (LED) ultraviolet sterilizing lamp, which comprises an LED light source, a bracket, a base, a power module and a control module. The LED light source can emit light with the wavelength of 100 to 280NM, and is spherical and arranged on the bracket. By the design, problems such as illuminating dead angles and the like of the common fluorescent tube can be avoided. By the spherical design, illumination at the largest angle can be realized without rotating the tube or a lamp holder. The bracket is fixed on the base, and the power module and the control module are arranged in the base. Sliding rollers are arranged on the bottom of the base, so that the sterilizing lamp is more convenient to move. The power module adopts an alternating current and direct current double-supply mode. When the alternating current is adopted for power supply, 220V alternating current can be reduced to low-voltage direct current through a transformer and a rectification circuit, and required stable voltage is provided for an LED driving circuit and the control module.

The invention discloses a clamp-type acromioclavicular joint embolia guiding system. The clamp-type acromioclavicular joint embolia guiding system comprises a coracoid side clamp, a clavicle side clamp and a handle, wherein a spherical base is arranged at the clamp tip of the coracoid side clamp; a conical tip protrusion is formed at the position, in contact with the coracoid side, on the surface of the spherical base; a rotatable hollow guiding device is arranged at the clamp tip of the clavicle side clamp. The clamp-type acromioclavicular joint embolia guiding system has the advantages that (1) the embolia of an acromioclavicular joint and central linear drilling between the coracoid and the clavicle are completed at a time; (2) drilling guidance is accurate, and the fracture of the coracoid and the clavicle is avoided; (3) by virtue of the accurate drilling guidance and the spherical design of the coracoid clamping end, the injury to important vascular nerves on the inner side of the coracoid during an operation is avoided; (4) the spacing between the clavicle and the coracoid is accurately measured in an outer measurement mode by virtue of a graduated scale at the far clamping end, so that the appropriate length of a loop needed by embolia fixing is selected; (5) the instrumentation is simple, convenient and safe, the operation wound is minimized, and a true minimally invasive effect is achieved.

The invention discloses a piston shoe and plunger assembly which comprises a piston shoe and a plunger. The piston shoe is used for being connected with a plunger end and being in sliding fit with aninclined plate of a plunger pump. A columnar cavity running through the plunger axially is formed in the plunger. A concave circular conical surface structure is arranged on the end, used for being connected with the plunger, of the piston shoe, a protruding local spherical structure is arranged at one end of the plunger, and line-surface contact sealing fit is realized between the circular conical surface structure and the local spherical structure. The conical surface is adopted for the piston shoe, the spherical design is adopted for the plunger end, the piston shoe and the plunger end fitand abut under the effect of a spring to form circular linear fit, fluid pressures on the two sides of a sealing line are communicated through the plunger cavity, the high-pressure acting force at thetwo ends of the plunger counteract, and the loads acting on the plunger end by the piston shoe are reduced; equivalently, the piston is only used as a sealing element for changing the volume of an oil cavity, the original needed axial bearing is reduced, a direct bearing piece is replaced with the inclined plate, the bearing value of the plunger and the piston shoe is greatly reduced, and therefore the piston shoe and plunger assembly is higher in wear resistance and longer in service life. The invention further discloses the plunger pump.

The invention discloses an improved Offner optical system for detecting an ultra-large-aperture concave aspheric mirror. Light emitted by a detection device is transmitted through a first compensationlens and a second compensation lens to a to-be-detected concave aspheric mirror, self alignment is performed, and then the processed light returns. The optical system selects a large incident light aperture angle and a first compensation lens bears a large aspheric normal aberration, thereby greatly improving the compensation capability; and the aspheric spherical aberration balance is realized under the condition of a small aperture ratio. The ratio of the caliber of the compensator to the caliber of the detected aspheric surface is very small and is only 0.025. With a two-piece compensatorstructure, the number of compensating lenses is small; on the basis of a full spherical design, the design limitation that a compensating system is aspheric for checking a large-caliber aspheric surface is broken through; the scheme is simple and the machining period is shorter; the image quality of an inspection light path is excellent; the wave aberration reaches a PV value superior to 0.1 lambda; and the improved Offner optical system is suitable for high-precision aspheric surface shape machining. Because of the improved Offner testing, the aspheric mirror testing of 14-m ultra-large aperture and ultra-large relative aperture of 1 to 1.43 can be realized.

The invention relates to a large image plane high resolution optical lens and belongs to the field of optical-mechanical-electronic integration. An optical system comprises 8 lenses, an aperture 4 and an imaging surface 10. A model is formed through the optimization and evolution of a double Gauss structure, through the reasonable allocation of optical power, the pixel can reach 8 million pixels, an image plane can reach 1 / 1'', and the structure is compact. According to the optical lens, a spherical design is employed, the processing performance is good, and the material cost is low. The product can be widely applied to the fields of industrial measurement and detection, intelligent transportation and the like.

The invention discloses a portable spherical direct methanol fuel cell. The portable spherical direct methanol fuel cell comprises a substrate, a grid hole shell, a plurality of positive current collecting plates, a catalyst layer, a methanol resistance layer, membrane electrodes, a negative current collector and external guide lines, wherein the grid hole shell is in the shape of a ball or an ellipsoid, the upper end of the grid hole shell is closed, an opening is formed in the upper end of the grid hole shell, and an end cover is arranged at the upper end of the grid hole shell; a pluralityof arc-like grids parallel to longitude lines are uniformly arranged on the peripheral wall of the grid hole shell along the circumferential direction; the end cover is provided with the external guide lines for connecting each positive current collecting plate; the positive current collecting plates, the catalyst layer, the methanol resistance layer and the membrane electrodes cling to the arc-like grids of the grid hole shell from inside to outside in sequence consistently; the membrane electrodes and the peripheral surface of the grid hole shell are coplanar; and the membrane electrodes arefastened to the peripheral surface of the grid hole shell in an arc-like mode and are in tight contact with the outer surfaces of the corresponding membrane electrodes. Through spherical design, theoutput performance and volume to power ratio of the call are improved, and simultaneously, the cell is convenient for subsequent maintenance while stack can be integrated to realize high-power output.

The invention relates to an eccentric spherical externally-conical sealing structure for engine pipeline. The eccentric spherical externally-conical sealing structure comprises a first guide pipe, a flat-pipe nozzle, an additional nut, an external conical connector and a second guide pipe. One end of the external conical connector is connected with one end of the flat-pipe nozzle, and the other end of the external conical connector is fixedly connected with the second guide pipe. The other end of the flat-pipe nozzle is fixedly connected with the first guide pipe. The additional nut is arranged at one end of the flat-pipe nozzle in the external conical connector and fitted with an outer thread of the external conical connector through an inner thread in a screw mode, thus the external conical connector and the flat-pipe nozzle are fixedly sealed. The eccentric spherical externally-conical sealing structure has the advantages that an eccentric spherical structure is adopted to lead to small weight, and a linear sealing structure is adopted to lead to good sealing effect; in a work environment, by a sealing line formed by the eccentric sphere and an inner conical surface, oil leakage probability is low, and maintainability is good; meanwhile a spherical design is adopted in the sealing structure, leading to effective repairability.

The invention discloses a wave plate design and error correction method in a contrast ratio adjustable point diffraction interference system. The light beam polarization state is adjusted in the modeof placing a quarter wave plate in a detection path, and then the interference stripe contrast ratio is adjustable. The problem is solved that when the wave plate is placed in a divergence spherical wave, a large wavefront error is generated. The wave plate design and error correction method is characterized in that that a flat and convex glass substrate of which the convex face is a non-sphericalface is adopted for the wave plate, and a plane is plated with a polarization membrane layer. Through even-order non-spherical design of the wave plate substrate, a wavefront distortion aberration caused when a large numerical value aperture sphere is detected is greatly lowered. By building a difference recovery model, a pose error generated on the wave plate is corrected. Since the even-order non-spherical quarter wave plate is fixed in design position in the detection path, after the pose error is corrected, the position of the wave plate does not need to be adjusted according to the change of the aperture numerical value of a mirror to be detected. The point diffraction system is easy to adjust, and the detection efficiency is improved.

The invention relates to the field of mechanical design and manufacturing, and discloses an independently mounted hydrodynamic retarder. The independently mounted hydrodynamic retarder comprises a hydrodynamic retarder cover, a rotor pump driving wheel, a stator pump driven wheel, a spline shaft, a hydrodynamic retarder shell, an electromagnetic proportional valve and a heat exchanger. By means ofoptimal structure design, the technology of separating the driving wheel and the driven wheel is adopted, and no-load loss generated when the retarder stops working is greatly reduced; and semi-spherical design is adopted by the overall appearance, stress is even, the heat radiating effect of the retarder is improved, and the use performance of the retarder is greatly improved. Aiming at the problem about medium oil recycling of an oil storage chamber of the retarder shell and overheating of the electromagnetic proportional valve, a corresponding solving design structure is provided, the oilreplacing frequency of the retarder is effectively reduced, and the heat exchange time of the retarder is effectively shortened; and the work efficiency is improved, cost is reduced, the service lifeof the retarder is prolonged, and the performance of the retarder is improved.

The invention discloses a portable foldable spherical drone. Aiming at the problems that the traditional multi-rotor UAV cannot be folded and takes up a lot of space, this UAV proposes a portable and collapsible spherical UAV solution. The UAV is divided into two states, namely the folded state and the unfolded state, and the two states can be converted to each other. Compared with the prior art, the technical solution adopted by the present invention has the following technical effects: the unique foldable spherical design makes the drone introduce some artistic elements, and the drone has a certain artistic appreciation; the compact self-locking The structural design ensures that the position of the arm and the fuselage of the UAV is relatively fixed when flying, and the UAV does not add additional mass; the unique folding structure and spherical structure design greatly improve the portability of the UAV. It is easy for users to carry it when going out and individual soldiers; when it is unfolded, the UAV is in quadrotor mode, with stable flight and simple operation.

The invention relates to a method of preparing an annular part from Ti2AlNb alloy and TiAl powder. Hot isostatic pressure diffusion bonding treatment on an alloy and powder is directly carried out, and forming of the powder and diffusion bonding of a special alloy are combined, so that a forming process is reduced, and the preparation cost is lowered. By adding an intermediate layer between the powder and the alloy, the method is simple in structure and good in manufacturability. A single reaction layer is obtained by directly diffusing elements between the powder and the alloy. Meanwhile, thehot isostatic pressure method can provide a uniform connecting stress distribution for obtaining a special alloy diffusion bonding annular part and reduces the stress concentration, so that the TiAlpowder and the Ti2AlNb alloy are reliably connected. The TiAl powder part is of a protruding semi-spherical design, so that amount of contraction of the TiAl powder in the hot isostatic pressure forming process is supplemented. A more precise annular structural part can be obtained, and the engineering application range of TiAl serial intermetallic compounds is expanded favorably.

The invention discloses a linear sealing pipeline connection structure, which is characterized by comprising an eccentric spherical surface, an inner conical surface, a size SRA, a size RB and a size C, wherein the eccentric spherical surface is matched with the inner conical surface to form the whole linear sealing pipeline connection structure; and a basic structure of the eccentric spherical surface is determined through the size SRA, the size RB and the size C. The linear sealing pipeline connection structure has the advantages that the weight of an aero-engine pipeline sealing structure is controlled, and a sealing effect of the structure is guaranteed. The structure adopts the eccentric spherical surface structure, so that the weight is relatively light; by the linear sealing structure, the sealing property is relatively high; under a working environment, the probability of oil leakage of a sealing line formed by the eccentric spherical surface and the inner conical surface is low, and relatively high maintainability is realized; when the eccentric spherical surface is matched with the inner conical surface, and an eccentric angle is formed, the structure can be still reliably sealed; and moreover, the sealing structure adopts spherical design, relatively high repairability is realized.

The invention is suitable for the field of optical lens, and aims to provide a camera lens for a projector, comprising a first lens, a second lens, a third lens, a fourth lens and a fifth lens sequentially arranged from an object direction to an image direction. The lens adopts glass and is a spherical lens; the first lens and the second lens are falcate lenses concave to the image direction; a lens protruding to the image direction is formed by adhering the third lens and the fourth lens together; and the fifth lens is a biconvex lens. Because the lens of the camera lens for the projector totally adopts a spherical design, various phase differences can be corrected through optimizing spherical coefficients such as spherical radius of curvature, intervals between lenses and thickness of the lenses so as to ensure that the camera lens for the projector reaches the demand of imaging quality. In addition, the lens made of glass can improve brightness and strengthen the light transmittance so as to obtain favorable imaging quality, reach the requirement of high resolution and small volume and reduce cost of the camera lens for the projector.

The invention discloses a low-resistance and efficient fluidization demister device and a demisting method thereof. A fluidization demister adopts a diameter-variable pipeline with a large top and a small bottom, wherein the diameter-variable pipeline is internally provided with a demisting cavity; airflow enters from the bottom of the diameter-variable pipeline and a demisting medium in the demisting cavity has a fluidized state under the action of the ascending airflow; meanwhile, the ascending airflow meets the demisting medium with the fluidized state; the direction of the airflow is deviated under the action of inertia, baffling and the like; liquid drops and solid grains in the airflow are continuously adsorbed, coagulated and intercepted by the spherical demisting medium; the airflow which is subjected to liquid drop removal by the demisting medium is exhausted from the top of the demister. Different proportions and porosity factors of the demisting medium are selected accordingto different air speeds and system parameters; the spherical design is adopted and has the characteristics of uneasiness of being blocked, easiness for washing, strong working condition adaptabilityand good fluidization effect; the demisting efficiency can be effectively improved, and the low-resistance and efficient fluidization demister device has the advantages of small investment, small resistance, uneasiness of being blocked and low operation and maintenance cost, and can meet the demisting requirements of various demisting occasions.

The present invention relates to a measuring instrument support, in particular to a rotating support for rolling steel measuring instruments, the lower column of which is fixed on one side of the steel strip, the cantilever is fixedly connected with the upper column, and the measuring instrument is placed in the instrument box on the end of the cantilever , the upper column and the lower column are connected with a sleeve part that allows the upper column to rotate around the lower column, the sleeve part is provided with a positioning part, and the positioning part blocks the sleeve part under normal conditions so that it cannot rotate. The bracket of the present invention is a rotating cantilever structure and can rotate freely when needed; the positioning hole adopts a conical hole, and the end of the positioning pin is designed as a spherical shape. The force rotates by itself to protect the internal measuring instrument from damage; the exterior of the instrument box is designed as a heat insulation structure, and a cooling water pipe can be introduced into the instrument box in the steel pipe of the bracket to cool the measuring instrument and ensure that the measuring instrument in the box is in a high temperature environment. can work normally.

The invention discloses a full-wedge type anti-explosion container. The container comprises a shell body, a cover plate, wedge strips and a locking piece, wherein the shell body uses a spherical design overall, and an opening of the shell body is an oval; a flange neck is arranged on the oval opening, and wedge strip clamping grooves and cover plate clamping grooves are formed in the flange neck;the wedge strip clamping grooves are located on the cover plate clamping groove, the cover plate clamping grooves are in a circle, and the wedge strip clamping grooves are in a long circle shape; thecover plate adopts an oval design, and a swallowtail-shaped guide rail is arranged on the upper surface of the cover plate along the center of a short axis; swallowtail-shaped grooves are formed in the bottom surfaces of the wedge strips, and the swallowtail-shaped guide rail cooperates with the swallowtail-shaped grooves; the wedge strips are two opposite semicircular arc-shaped structures, an inclined plane with a downward gradient is arranged on the edge of the upper surface of each semicircular arc-shaped structure of the corresponding wedge strip, and a positioning hole is formed in one end of each wedge strip; and the wedge strips are assembled on the cover plate and are fixedly connected with the cover plate, so that the wedge strips are prevented from slipping off the cover plate.The full-wedge type anti-explosion container is simple in structure, safe, reliable and rapid in opening and closing.

The invention relates to a turbine, in particular for a continuous-flow power plant, comprising the following features: • a hub body (11) which has a shaft for transmitting the torque which is generated by the turbine to a mobile machine; • a number of turbine blades which are supported by the hub body and can be rotated about the longitudinal axes thereof; • an adjusting body (10) is provided in the interior of the hub body, designed in the manner of a spherical link chain, which adjusting body (10) runs coaxially with respect to the shaft and can be rotated about the shaft axis; • a link chain for each blade with two links (1, 2), namely a first link (1), the first end of which is articulated on the adjusting body via a rotary joint, and a second link (2), the first end of which is articulated on the second end of the first link via a rotary joint, and the second end of which is mounted on the hub body such that it can be rotated about the longitudinal axis of the relevant blade; • wherein the adjusting body comprises a drive journal (10.1) and a ball socket (10.2), and • at least the first link (1) is of spherical design as viewed in side view.