47results about How to "Reduce flatness requirements" patented technology

The utility model discloses a barb clamping jaw strength testing device which comprises a base, a fixing seat is arranged on the base, a simulation mounting groove is formed in the fixing seat, a barb clamping jaw is arranged in the simulation mounting groove through a mounting bolt, and the groove bottom face of the simulation mounting groove is used for limiting the extending posture of the barb clamping jaw. An oil cylinder is further arranged in the stress direction of the barb clamping jaw, the telescopic end of the oil cylinder is connected with a rod joint bearing through a force sensor, the rod joint bearing is connected with a convex jaw through a rotating shaft, the convex jaw is arranged at the extending end of the barb clamping jaw in a sleeving mode and exerts acting force, and the oil cylinder is arranged on the base. According to the utility model, the maximum failure load bearing capability of the barb jack catch and the anti-shearing capability of the fixed bolt can be tested.

The utility model relates to the technical field of compression molding devices, and provides a compression molding device utilizing a roller for compression, which comprises an outer cover, a base and a pressing component, the outer cover is connected to the base in a vertically liftable manner, and the pressing component is mounted in the outer cover; the material pressing assembly comprises a second driving piece, a pressing plate, a plurality of roller bars, a compaction belt and a compaction belt driving sub-assembly. The multiple roller bars are arranged below the pressing plate, the compaction belt is installed below the roller bars through the compaction belt driving sub-assembly, one face of the compaction belt is used for making contact with the roller faces of the roller bars, and the other face of the compaction belt is a pressing face. The roller bars can synchronously rotate to roll materials in the pressing process, so that the requirement on the flatness of the cloth is reduced, and the pressing quality is ensured; the problems that in the pressing process of an existing pressing forming device, due to the fact that roller bars rotate sometimes and do not rotate sometimes, the pressing effect is poor, the requirement for cloth flatness is high, the pressing difficulty is large, and the production efficiency is low are solved.

The utility model relates to a side-cooled BDU and a battery pack, the side-cooled BDU comprises an upper shell, a lower shell and a liquid cooling plate, the liquid cooling plate is located on one side of the upper shell, and the bottom of the liquid cooling plate is connected with the lower shell. According to the utility model, the liquid cooling plate is arranged on the side surface of the BDU shell, so that the height size of a BDU system can be effectively reduced; the lower shell and the liquid cooling plate are connected through the plate spring nut installed later, the complexity of a BDU lower shell mold is simplified, meanwhile, the deformation characteristic of the plate spring nut can absorb the tolerance between the liquid cooling plate and a fixing face, and the planeness requirement of a part installation face is lowered.

The invention provides a hybrid bonding structure and bonding method based on an interlocking structure, and the structure comprises a first chip to be bonded, which is provided with a silicon oxide layer and a first connecting piece protruding out of the silicon oxide layer; the second chip to be bonded is provided with a polyimide layer, a recess arranged in the polyimide layer and a second connecting piece arranged at the bottom of the recess, the surface of the second connecting piece is provided with a first adhesion layer, and the first connecting piece and the second connecting piece are made of copper and / or aluminum; the first chip to be bonded and the second chip to be bonded are configured as follows: before bonding, the height difference of the first connecting piece protruding out of the oxide layer is greater than the height difference of the top surface of the first adhesion layer and the top surface of the silicon oxide layer; the silicon oxide layer is connected with the polyimide layer, and the first connecting piece extends into the recess and is connected with the second connecting piece through the first adhesion layer to form an interlocking structure. The method is used for optimizing the performance of the hybrid bonding process and the bonding structure.

The present application relates to a backwash water and air distribution filter brick and a water and air distribution device for a sulfur autotrophic denitrification filter tank, and relates to the technical field of sewage treatment equipment. The backwash water and air distribution filter brick for the sulfur autotrophic denitrification filter tank in the present application includes a bottom plate, a first side plate, a second side plate and a partition plate, forming a primary distribution chamber for backwash water, a secondary distribution chamber for backwash water and a secondary distribution chamber for backwash air, and realizing uniform water and air distribution through multiple through holes and a secondary particle retention component. The present application also provides a backwash water and air distribution device comprising the above-mentioned backwash water and air distribution filter brick. The structural design in the present application reduces the loss of sulfur autotrophic slow-release materials, reduces the risk of filter brick clogging, improves backwash efficiency, and at the same time reduces the construction depth of the filter tank, saving investment.

The utility model relates to a heat dissipation technical field, concretely relates to a pouring and sealing heat dissipation structure. A pouring and sealing heat dissipation structure, include: shell, the shell upper end opening, the opening place forms the flanging, element, the element is placed in the shell, the upper surface of element with the opening of shell is flush, the clearance between element and shell pours into the heat conducting glue, top heat conducting pad, top heat conducting pad is bonded and fixed in the flanging, the lower surface of top heat conducting pad is bonded with the upper surface of element. The technical problem of increasing cost and weight of pouring and sealing heat dissipation mode in the prior art to put the magnetic piece completely in the complex structure mounting groove pouring and sealing needs a large number of heat conducting glue.

This invention discloses a method for fixing tubular components with adhesive, aiming to solve the problem of adhesive and tubular workpieces protruding above the product surface during the adhesive filling process, affecting product quality. The invention includes the following steps: S1, injecting adhesive into a groove on the product to be filled, covering the bottom of the groove with a base layer of adhesive; S2, inserting the tubular workpiece into the groove; S3, pressing a clamping fixture onto the tubular workpiece, ensuring the highest point of the tubular workpiece is below the surface of the product; S4, allowing the base layer of adhesive to cure; S5, removing the clamping fixture; S6, injecting side adhesive into both sides of the tubular workpiece at the groove opening to form side adhesive, and smoothing the adhesive surface to make it flat; S7, allowing the side adhesive to cure. This method for fixing tubular components with adhesive in this patent application reduces the flatness requirements after bending the tubular components, thereby reducing the difficulty of bending the tubular workpieces. During the adhesive filling process, the adhesive and tubular workpiece will not protrude above the product surface, ensuring product quality.

According to the multi-chip substrate packaging structure and the preparation method thereof, the front face of a first chip set is in bonding connection with the upper end face of a first circuit layer, one end of a first metal column is electrically connected with the upper end face of the first circuit layer, and the first metal column and the first chip set are plastically packaged in a first plastic packaging structure; the other end of the first metal column is exposed on the upper end surface of the first plastic package structure; the front surface of the second chip group is in bonding connection with the lower end surface of the second circuit layer, one end of the second metal column is electrically connected with the lower end surface of the second circuit layer, the second metal and the second chip group are plastically packaged in a second plastic packaging structure, and the other end of the second metal column is exposed on the lower end surface of the second plastic packaging structure; the other end of the first metal column is electrically connected with the other end of the second metal column, and the upper end face of the first plastic package structure is bonded with the lower end face of the second plastic package structure. According to the invention, more chips can be installed in a packaging space with a specific size, and the processing difficulty is low.

The invention relates to the technical field of construction, in particular to a terrain adaptation type fabricated foundation and a using method thereof.The terrain adaptation type fabricated foundation comprises prefabricated bases and a plurality of steel channel beams used for connecting the adjacent prefabricated bases, adjusting steel columns are arranged in the prefabricated bases, and a plurality of steel column thick flat screw holes are formed in the two symmetrical walls of each adjusting steel column; short column thick flat screw holes corresponding to the steel column thick flat screw holes are formed in the prefabricated base; a plurality of fine-flat bolts are fixed on the upper surface of the adjusting steel column, fine-flat nuts are in threaded connection with the fine-flat bolts, an adjusting steel plate is erected on the fine-flat nuts, the adjusting steel plate is arranged on the fine-flat bolts in a penetrating manner, and a filling material is arranged between the adjusting steel plate and the adjusting steel column. The terrain adaptation type fabricated foundation is simple in structure and convenient to operate, can be used for the flat ground and can also be suitable for the abrupt slope field, the requirement for the flatness of the field is lowered, and the foundation treatment cost is reduced.

This utility model discloses a 3D printing additive manufacturing equipment, which includes a control power supply and a pneumatic control device. The core structure also includes: a lifting plate connected to a lifting drive mechanism; an ultraviolet lamp irradiation module mounted on the lifting plate and having an adjustable light direction ultraviolet lamp assembly; a dispensing module mounted on the ultraviolet lamp bracket, with the dispensing end surrounded by the ultraviolet lamp assembly and the air inlet end connected to the pneumatic control device; a positive power supply connection block sleeved on the dispensing end of the dispensing module and connected to the positive terminal of the control power supply; and a dispensing platform located below the dispensing module, with a metal negative pressure plate at the top and connected to the negative terminal of the control power supply. In addition, a heating module is provided outside the dispensing module, and the lifting drive mechanism adopts a double guide rail and lead screw nut assembly to ensure accuracy. This equipment is based on electrohydrodynamics (EHD) technology and drives dispensing through "electric field + air pressure", which has non-contact printing characteristics, high printing accuracy and stability, and is suitable for processing complex display screen structures.

The utility model relates to a kind of lens driving device, camera module and electronic equipment, including frame, and the dynamic frame that frame is moved in the plane perpendicular to optical axis, dynamic frame includes the dynamic body that is moved along the first axis of plane under the drive of first drive component, carrier is moved along and the second axis that is perpendicular to first axis relative to dynamic body under the drive of second drive component, frame and dynamic body between, and dynamic body and carrier between respectively be equipped with motion holding component, motion holding component includes single ball and the ball group formed by several balls, the ball group between frame and dynamic body respectively with frame and dynamic body multiple-point movable contact, the ball group between dynamic body and carrier respectively with dynamic body and carrier multiple-point movable contact.Advantage is that: adopt the hybrid structure of single ball and ball group combination.Single ball provides accurate guidance, ball group compensates plane error by multiple-point support, significantly reduces the requirement to the flatness of part, fundamentally improves the reliability, durability of product.

The application belongs to the technical field of foundation engineering construction, and particularly relates to a marking and line drawing device based on foundation engineering construction, which comprises at least two fixing members for being inserted into the ground, a mounting frame, a winding drum, a steel rope, a swivel, a butt joint member, a moving member, a mounting member and a barrel. The top end of each fixing member is provided with a mounting frame with a through hole opened on the side surface. Two winding drums are rotatably connected in the mounting frame. The winding drum is wound with a steel rope which is threaded out of the through hole. The mounting frame is rotatably connected with a swivel. After the anchor rod is vertically inserted into the base point, the butt joint member is used to butt joint the steel rope and the swivel. The direction limiting member limits the rotating direction of the winding drum. The straightened steel rope forms a track for the moving member to walk. The barrel is hung on the rotating rod. The upper power wheel and the lower power wheel move along the steel rope. The barrel discharges to draw a straight line. The requirement for the flatness of the ground is low. The discharging direction is stable. The use mode is flexible. The practicality and the line drawing efficiency are high.

The utility model provides a kind of pressure-resistant anti-relaxation metal rubber strip sealing gasket, belong to sealing gasket technical field.It includes sealing gasket metal base plate, the medium passes through hole is equipped in the middle of sealing gasket metal base plate, rubber strip installation groove is correspondingly equipped in the upper and lower position of the two sides of one perimeter of sealing gasket metal base plate close to medium passes through hole, annular sealing rubber strip is equipped in rubber strip installation groove, and bolt mounting hole is uniformly distributed on the circumference of sealing gasket metal base plate.The utility model is made into sealing gasket by the composite structure of metal and rubber, with high strength and good sealing, greatly improve the sealing performance of sealing gasket, solve the problem of existing technology that sealing gasket is easy to relax, high-pressure sealing and cost.

The invention relates to a scientific investigation winch quick disassembly and assembly type bottom foot which comprises a frame welding base, a deck welding installation plate, installation pins, fastening screws and cushion blocks, the frame welding base is welded to a scientific investigation winch structure frame, and the deck welding installation plate is connected with the frame welding base through the installation pins; and the deck welding mounting plate, the mounting pins and the scientific investigation winch structure frame are connected into a whole through fastening screws. The rapid disassembly and assembly type bottom foot for the scientific investigation winch is applied to connection of the scientific investigation winch and a deck, on the premise that the structural strength is guaranteed, the rapid falling and installation functions are achieved, stable installation of the scientific investigation winch is guaranteed, and the rapid disassembly and assembly type bottom foot is suitable for deck faces with different flatness degrees.

The utility model provides a fixing device for micro pile embedded section steel. The fixing device comprises an adjustable supporting rod, an anchoring chassis and an adjustable section steel hoop. The adjustable profile steel hoop is of a hoop structure with the shape of an inner opening matched with the shape of the embedded profile steel, the size of the inner opening of the adjustable profile steel hoop is adjustable, and the adjustable profile steel hoop is used for surrounding and fixing the embedded profile steel. The upper ends of the adjustable supporting rods are hinged to the periphery of the adjustable profile steel hoop, the anchoring chassis is installed at the bottom ends of the adjustable supporting rods, and the length of the adjustable supporting rods is adjustable. The anchoring chassis is used for being fixed to the ground. The device has the advantages that the labor intensity of workers is reduced, the construction efficiency is improved, the use of engineering instruments is reduced, and the construction cost is reduced.

This invention provides a hybrid bonding structure and bonding method based on an interlocking structure. The hybrid bonding structure includes: a first chip to be bonded, having a silicon oxide layer and a first connector protruding from the silicon oxide layer; and a second chip to be bonded, having a polyimide layer, a recess within the polyimide layer, and a second connector at the bottom of the recess. The surface of the second connector is provided with a first adhesive layer. The materials of the first and second connectors include copper and / or aluminum. The first and second chips to be bonded are configured such that: before bonding, the height difference of the first connector protruding from the oxide layer is greater than the height difference between the top surface of the first adhesive layer and the top surface of the silicon oxide layer; after bonding, the silicon oxide layer and the polyimide layer are connected, and the first connector extends into the recess and is connected to the second connector using the first adhesive layer, thus forming an interlocking structure. This invention is used to optimize the performance of the hybrid bonding process and bonding structure.

The present application provides a hoisting device for bridge engineering construction, which relates to the field of hoisting technology, including two brackets, rollers installed at the bottom of the brackets, and a main beam and a hoisting group installed between the two brackets; the main beam is spliced ​​by multiple parts and installed vertically on the bracket, and each bracket is provided with an auxiliary beam, a first moving groove is provided on the bracket, and a second moving groove is provided on the main beam corresponding to the first moving groove, and a moving mechanism is installed on the bracket, and the moving mechanism can drive the auxiliary beam to move along the first moving groove and the second moving groove, and the hoisting group is installed on the auxiliary beam, and the hoisting group can move on the auxiliary beam, and the hoisting group is used to hoist objects; when the main beam needs to be installed on the bracket, an auxiliary beam is installed on one bracket and the two auxiliary beams cooperate with each other. The present application can reduce the demand for construction sites and the difficulty of operation during the installation process.

This utility model discloses a porous vacuum suction cup, including a suction cup with a matrix of suction holes on its top. The suction holes are connected by intersecting grooves. A sealing strip surrounds the matrix of suction holes. The suction cup also has independent second suction holes on its top, which communicate with the grooves. Each suction hole has a sealing ring. The sealing strip is fixed in a frame groove on the top of the suction cup, which communicates with the grooves. A tube head is located on one side of the suction cup, communicating with both suction holes. The advantages of this utility model compared to existing technologies are: each suction hole forms a small adsorption area with a sealing ring, and the matrix of suction holes forms a complete adsorption area; additionally, a second complete adsorption area is formed by the grooves connected within the sealing strip via the second suction hole. Simultaneous adsorption in both areas increases the adsorption area, resulting in a more stable dual adsorption effect and improved assurance for smooth processing.

The invention relates to the technical field of indoor building decoration, in particular to a wall decoration plate buckle splicing type installation structure which comprises a leveling bolt fixed to a wall through an expansion bolt, and further comprises a buckle splicing mechanism connected with the leveling bolt, the buckle splicing mechanism comprises a locking assembly and a buckle assembly. The locking assembly is connected with the leveling bolt, and the buckle assembly is detachably connected with the locking assembly; according to the buckle splicing type installation structure for the wall face decoration plates, the assembly type and rapid construction concept is met, the wall face construction technology is simplified, the construction period is shortened, buckle type fixing is firm and not prone to loosening, and later disassembly, assembly, maintenance and upgrading are convenient.

The present application relates to a center of gravity measuring device and a method for measuring the center of gravity of a drone. The center of gravity measuring device includes: a platform scale; a bracket, which is movably arranged on the platform scale, and the bracket includes a bottom plate, a support plate and a top plate, one end of the support plate is connected to the bottom plate, and the other end of the support plate is connected to the top plate; a support block, which is arranged on the upper surface of the top plate; an ejector pin, which is movably arranged on the support block; a plumb bob, which is suspended on the top plate, and when the bracket is in a horizontal state, the bottom end of the plumb bob is aligned with the center of the bottom plate. The center of gravity measuring device of the present application has a simple structure, does not require high flatness of the use site, and can measure accurately.

The invention provides an optical sensor and a packaging method thereof. The packaging method comprises the following steps: fixing a chip on a substrate; a transparent DAF film is attached to the surface of the glass monomer; attaching a glass single body to the surface of the chip; silk-screen printing hydrosol on the surface of the glass monomer; bonding a chip bonding pad with a substrate bonding pad lead to obtain a semi-packaged device; performing plastic package on the semi-packaged device to obtain a plastic package device; grooving the plastic package device until the hydrosol is exposed; and removing the hydrosol and the plastic packaging material on the surface of the glass monomer to finish windowing packaging. A cofferdam is not required to be photoetched in the whole process, so that not only can the optical performance of the optical sensor be improved by using the coated glass, but also water vapor entering caused by film layering or falling can be avoided, and the reliability of the optical sensor is ensured; the hydrosol can be completely removed when the molding compound on the surface of the glass is removed, and no glue is left; in addition, the requirement for the flatness of the substrate is not high during plastic packaging, the process difficulty is reduced, and the problem that an existing optical sensor packaging method is low in efficiency is solved.

The present invention discloses a multi-electrode electromagnetic solid interface performance measurement method and device. The resistivity and contact resistance of the sample to be measured are obtained by the current between two anisotropic current sources and the potential difference between two points on the interface, and the resistivity and contact resistance of the sample to be measured are obtained, and the distribution of the normal / tangential stress of the contact surface is obtained by substituting them into the established force-electric contact model, and then the contact surface defects and internal defects corresponding to the stress distribution are obtained; at the same time, the normal stress distribution corresponding to the rough interface is used to obtain the rough interface edge contour curve, and the random number generation seed is obtained by reverse calculation, and then the random number generation seed is fixed in the non-Gaussian numerical simulation process to obtain a uniquely determined interface morphology. The measuring device includes a support frame, a counterweight host, a slide rail, an active pulley and a copper elastic electrode. The present invention obtains the performance, characteristics and load on the electromagnetic solid contact interface by measuring the electrical signal, and realizes the synchronous measurement of the contact interface / internal defects and interface morphology.

The utility model relates to a universal bicycle returning device for shared electric bicycles and bicycles, which is provided with a corresponding central control system and comprises a lock pile, a front wheel limiting groove, a bicycle returning sensing module and a bicycle-mounted locking module. The vehicle-mounted bicycle locking module has the advantages that the bicycle locking rod is arranged in the groove-shaped cavity of the bicycle locking sub-pile, the anti-damage capacity is higher, the size of the vehicle-mounted bicycle locking module is small, the gravity center of the vehicle-mounted bicycle locking module is close to the inside, and the influence of the weight of the vehicle-mounted bicycle locking module on riding experience is reduced; the shape of the cavity of the bicycle locking sub-pile plays a guiding role; the bicycle locking rod can roll in the axial direction, the friction force between the bicycle locking rod and the spring bolt is reduced, and bicycle returning and bicycle locking are smoother; a cavity formed in the bicycle locking sub-pile plays a role in protecting the bicycle locking sub-pile from being damaged; the limiting groove mounting groove is matched with the bulge arranged on the surface of the lock pile base plate, so that the mounting is more convenient, the positioning is more convenient, and when a plurality of lock piles need to be arranged at one station, the lock pile base plate is lengthened, and then the plurality of lock piles and the front wheel limiting groove are repeatedly fixed.

The double-wheel electric differential steering wheel with the hydraulic jacking function is characterized in that the double-wheel electric differential steering wheel comprises a plunger type hydraulic jacking mechanism and two driving units, and the driving units are arranged on the two sides of the plunger type hydraulic jacking mechanism respectively; the driving unit is composed of a reduction gearbox and wheels, the reduction gearbox comprises a box body and a box cover, the box body and the box cover are connected through bolts, a speed reducer is installed on one side of the box body, and a walking motor is installed at the input end of the speed reducer; and the wheels are installed on the other side of the box body through hubs, the two box covers are connected with a connecting plate through screws, the two ends of the connecting plate are fixedly connected and hinged to fixing bases correspondingly, and two hinge shafts are symmetrically welded to the plunger type hydraulic jacking mechanism. The invention relates to the technical field of steering wheels, in particular to a double-wheel electric differential steering wheel with a hydraulic jacking function. The technical problem to be solved by the invention is to provide the double-wheel electric differential steering wheel with the hydraulic jacking function, so that material transfer is facilitated.

The utility model relates to the technical field of automobile oil tanks, and discloses an oil tank oil filling port assembly which comprises an oil tank shell, an oil tank oil filling port, a first oil filling port, a second oil filling port, a second oil filling port, a first oil filling port and a second oil filling port. The oil filling port is formed in the mounting hole, a first annular protrusion is integrally formed on the peripheral wall of the oil filling port, and the first annular protrusion abuts against the first arc-shaped face to form a welding seam; the installation channel assembly is arranged in the oil tank shell corresponding to the installation hole, and the second end of the oil filling port is arranged in the installation channel assembly in a sealed mode. According to the oil tank oil filling port assembly, the first arc-shaped face and the first annular protrusion abut against each other to form the welding seam, the second end of the oil filling port is installed in the installation channel assembly in a sealed mode so that accurate positioning and stable clamping of the oil filling port can be facilitated, and therefore the requirement for the flatness of a welding area is lowered while the welding quality is guaranteed; and the number of parts and procedures can be reduced, and the production cost can be reduced.

The utility model relates to the technical field of excavators, in particular to a towing cable support structure, a track frame and a towing excavator. The support structure comprises a bearing frame, a supporting frame and a cable barrel. The bearing frame is arranged on the lower side of the track frame, the bearing frame comprises a fixing part and a connecting part, the two ends of the connecting part are connected with the first end of the fixing part respectively, and the second end of the fixing part is fixed to the bottom side of a lower cover plate of the track frame; the supporting frame comprises a supporting ring and supporting rods, the supporting rods are located on the two sides of the supporting ring and fixed to the bearing frame, and the cable barrel is inserted into the supporting ring of the supporting frame. The cable support solves the problems that an existing cable support structure has high requirements for planeness of an upper cover plate and a lower cover plate, assembly is difficult due to large welding deformation, and the structure is heavy.

The invention provides a hybrid bonding structure and bonding method based on an interlocking structure, and the structure comprises a first chip to be bonded, which is provided with a first silicon oxide layer and a first copper connecting piece protruding out of the first silicon oxide layer; the second chip to be bonded is provided with a second silicon dioxide layer, a recess arranged in the second silicon dioxide layer and a second copper connecting piece arranged at the bottom of the recess, and the surface of the second copper connecting piece is provided with a first adhesion layer; the first chip to be bonded and the second chip to be bonded are configured as follows: before bonding, the height difference of the first copper connecting piece protruding out of the first silicon oxide layer is smaller than the height difference of the top surface of the first adhesion layer and the top surface of the second silicon oxide layer; the first silicon oxide layer is connected with the second silicon oxide layer, and the first copper connecting piece extends into the recess and is connected with the second copper connecting piece through the first adhesion layer to form an interlocking structure. The method is used for optimizing the performance of the hybrid bonding process and the bonding structure.

The utility model belongs to the field of photovoltaic technology, and relates to a photovoltaic support for rotatably installing a photovoltaic module, which comprises two rotating arms, two photovoltaic module installing rods, a connecting plate and an adjustable threaded upright post, the rotating arms are symmetrically arranged in a group, connecting holes are arranged at two ends of each rotating arm, the photovoltaic module installing rods are symmetrically arranged in a group, two photovoltaic module installing rods are arranged in a group, and the connecting plate is connected with the adjustable threaded upright post. The rod body is provided with a boss and an assembly mounting hole, the boss is connected with one ends of the rotating arms, the connecting plate is provided with two connecting holes and connected with the other ends of the two rotating arms, and the adjustable threaded stand columns are symmetrically arranged in a group and serve as rotating, lifting and fixing devices of the connecting ends of the connecting plate and the rotating arms. According to the utility model, the installation form of the photovoltaic assembly is enriched, the rotary installation can be adapted to photovoltaic assemblies of various specifications, the requirement on the flatness of a foundation is not high, and the design is simplified, so that the concrete which has larger dead weight and is convenient to form becomes a main component of the photovoltaic support.