80results about How to "Reliable suspension" patented technology

The invention discloses a rotatable electroplating rack. The rack comprises main rods, a cross beam, a plurality of gears, gear shafts and fixtures; the main rods are perpendicularly fixed at two ends of the cross beam; hooks are arranged at upper ends of the main rods; a plurality of through holes are formed in the cross beam; one of the gears and a rotating shaft are assembled and then are connected with an output end of a motor through a coupler; the rest gears and the gear shafts are assembled and then penetrate through the through holes; the fixtures used for electroplating of different types of workpieces are arranged at the other ends of the gear shafts; and meanwhile, special fixtures are designed for cylinder block type parts and thin and long shaft type parts particularly, so that the electroplating problems caused by the relatively large mass of the cylinder block type parts and the relatively small diameters of the thin and long shaft type parts are solved. The rack is simple in structure, multiple parts can be electroplated simultaneously, the workpieces are clamped firmly and reliably and are convenient to mount and dismount, the phenomenon of falling into a tank is avoided, the torque is input and the outer meshing gears rotate to drive the workpieces to rotate continuously in the electroplating process, the plating is uniform in thickness, the electric current density is increased, the electroplating time is shortened, and the efficiency is improved.

The invention relates to a device which enables two petroleum casing pipes with different diameters to be hanged and connected by expanding the casing pipes underground, and a construction technology.The device comprises a drilling string, an expansion pipe hanging body, a length-adjusting scroll cover set, an expansion transmitting room and a tail pipe connection pair and is characterized in that the drilling string consists of an adjusting-centering pipe nipple, a transition drill pipe, a push-pull central pipe and a bearing screw cap; the expansion pipe hanging body consists of a casing pipe, a hanging pipe, a hanging projection and a hanging rubber ring; the length-adjusting scroll cover set consists of a length-adjusting scroll cover and a clamping nut; the expansion transmitting room consists of a pull cap, a propelling piston, an expansion head, an upper expansion pipe cavity body, a lower expansion pipe cavity body, a steel ball, a transmitting seat, an O-shaped seal rig and acirclip for a hole; and the tail pipe connection pair consists of a lower expansion pipe, a tail pipe connection hoop and tail pipes. The invention has the advantages that hanging modes of hydraulicpush, lubrication expansion head and hard and soft combination are adopted, thereby having reliable tightness and strong hanging capability; and circulation of drilling fluid, injection of cement paste and hanging connection can be completed in one construction, and thereby convenient operation is achieved.

The invention discloses a novel lock catch type grounding wire anti-falling hook device with a bottom opening, which is reasonable, rigorous and reliable in structure and can effectively prevent a grounding wire from falling off. Through a sealing cross rod structure, the problem that the grounding wire falls off is solved directly and fundamentally. The hook device is mainly composed of a main hook, an arc-shaped pressing piece, a torsion spring, an operating mechanism, a sealing transverse rod and the like. When the hook is hung on a lead, the sealing cross rod can be automatically opened; after being hung, the sealing cross rod can be automatically closed, and the operation mechanism can realize self-locking of the T-shaped sliding block, so that the sealing cross rod cannot be downwards opened; when the hook device needs to be taken down, only self-locking of the T-shaped sliding block needs to be removed, the sealing cross rod is opened downwards automatically, and then the hook device can be taken down smoothly; when the hook is hung on a wire, the arc-shaped pressing sheet can be tightly pressed on the outer side of the wire under the action of the torsion spring. The operating mechanism comprises a T-shaped sliding block with an inclined hole, a T-shaped sliding groove and a transverse pull rod.

The invention discloses a refrigerator shelf assembly and a refrigerator provided with the same. The refrigerator shelf assembly comprises a shelf, shelf supports and locking devices, wherein the shelf comprises a horizontally-positionedshelf body; the shelf supports extend vertically, are arranged on the inner wall of the refrigerator and are provided with a plurality of positioning holes formed in the vertical direction of the shelf supports at intervals, and the shelf is hung on one of the positioning holes of each shelf support; and the locking devices are connected with the shelf and matched with certain positioning holes to lock the shelf on the shelf supports. According to the refrigerator shelf assembly provided by the embodiment of the invention, the shelf can be locked to the shelf supports through the arranged locking devices, the shelf is mounted and positioned more stably and more reliably, and accordingly the situation that theshelf falls off the shelf supports due to vibration of the refrigerator can be avoided.

The invention discloses a self-adjustment type five-freedom-degree magnetic bearing. The self-adjustment type five-freedom-degree magnetic bearing comprises outer stator cores, inner stator cores and a cylindrical rotor. The cylindrical rotor is sequentially sleeved with the cylindrical inner stator cores and the cylindrical outer stator cores from the inner circle to the outer circle. A tooth socket structure is adopted for the inner stator cores. Four pairs of inner stator teeth are evenly distributed in each inner start core along the circumference. Two pairs of inner stator teeth are oppositely arranged on each inner stator core in the horizontal direction. Two pairs of inner stator teeth are also oppositely arranged on each inner stator core in the vertical direction. The eight inner stator teeth are formed, and a radial suspension winding is wound around each of the eight inner stator teeth. The self-adjustment type five-freedom-degree magnetic bearing solves the problems that when an existing magnetic bearing bears heavy rotors and loads are too large, the torsion of the rotor is too large, and the rotor suspension is influenced; meanwhile, the structure of the five-freedom-degree magnetic bearing is simplified; meanwhile, a control element of the five-freedom-degree magnetic bearing is omitted; and the self-adjustment type five-freedom-degree magnetic bearing has the beneficial effects that the suspension performance is reliable and the self-adjustment type five-freedom-degree magnetic bearing is easy to control.

The invention relates to the technical field of underground coring devices, in particular to a locking jaw suspension type pressurized coring device. The locking jaw suspension type pressurized coring device comprises an upper joint, a bearing base, an outer cylinder, a drill bit, a casing, a flow separating joint, a locking jaw casing, a locking jaw, a guide casing, a limiting sleeve, a bearing joint, an inner cylinder and a rock core jaw. The locking jaw suspension type pressurizing centering device has the advantages that the structure is reasonable and compact; after the coring is finished, the pressurizing is performed, the locking jaw is unlocked, the pressurizing sleeve, the guide sleeve, the limiting sleeve and a press sleeve continuously move down and push the bearing joint and the inner cylinder, the rock core jaw mounted at the lower end of the inner cylinder is forced to retract and deform, and the purpose of pressurized coring is realized; finally, a pressure relief ball is thrown in, a pin on the pressure relief sleeve is sheared off, a pressure relief hole in the casing is exposed, and drilling liquid can smoothly circulate; the suspension is more reliable, the unlocking is convenient, and the pressure relief is smooth; by throwing the corresponding ball, the coring drilling, core cutting and pressure relief are realized, so that the whole coring process is completed, and the construction is convenient and rapid.

The invention discloses a rail sliding type arc extinguisher. The rail sliding type arc extinguisher comprises a magazine (1) and an arc extinguishing cylinder (6), wherein a triggering coil (3) and an arc guide fitting (9) are arranged inside the magazine (1); an arc guide electrode (8) connected with the arc guide fitting (9) and a gas pill triggering position are arranged at the bottom of the magazine (1); a side surface electrode (5) is arranged on the sidewall of the gas pill triggering position, wherein a spiral suspended rail (2) from top to bottom for bearing an arc extinguishing gas pill (4) is arranged on the inner wall of the magazine (1), and a groove matched with the spiral suspended rail (2) is formed in the surface of the arc extinguishing gas pill (4) which is mounted inside the magazine (1). The rail sliding type arc extinguisher is simple in structure, safe and reliable; the arc extinguishing gas pill inside the magazine is capable of sliding down smoothly only under the action of the gravity, and therefore, the step of pill changing after once triggered arc extinguishment is realized.

The invention relates to the technical field of thermal recovery wellhead devices, in particular to a thermal recovery casing head. The thermal recovery casing head comprises an oil-string casing, a casing body, a Christmas tree bottom flanged joint, a hanger and slips, wherein the outer side of the lower portion of the Christmas tree bottom flanged joint is fixed to the inner side of the upper portion of the casing body in a threaded connection mode, the upper end of the oil-string casing is sleeved with a large-diameter hole in the lower portion of the Christmas tree bottom flanged joint, and the oil-string casing is sleeved with a gland located on the inner side of the casing body. By arranging countersunk head threaded shear pins in a countersunk head hole and a horizontal threaded hole to hang the slips, hanging can be achieved reliably; by arranging the Christmas tree bottom flanged joint, mechanical sealing performance is high; machining and installing processes are simplified, and using is convenient; through two groups of welding, connecting strength of the oil-string casing is guaranteed, deformation and sinking of the oil-string casing during frequent gas injection are avoided, weld failure, oil-water leakage and environment pollution are prevented, and the thermal recovery casing head has the advantages of being safe, capable of saving labor, convenient to use and efficient.

The invention discloses an automobile engine suspension mounting structure. A left suspension and a right suspension are mounted on the left side and the right side of a cylinder body respectively, a rear suspension is mounted on a tail housing of a transmission, each of the left suspension and the right suspension comprises an elastomer, an upper limiter, a lower limiter and a suspension support, the rear suspension comprises a rear suspension support and a rear suspension cushion assembly, the side plates of the lower limiters extend upwards, the upper portions of the extending parts of the lower limiters are folded inwards to form limit portions, the rear suspension support is a 'U'-shaped frame, the left end and the right end of an upper suspension plate extend downwards and extend horizontally towards the inner side after overpassing the ends of a lower suspension plate, and the middle of the front end of the lower suspension plate first extends forwards and then extends vertically upwards to form a forward-rush preventing limit plate. A forward-rush preventing rubber cushion block is sleeved with the forward-rush preventing limit plate, the middle of the rear end of the lower suspension plate extends backwards and then extends vertically upwards to form a backward-rush preventing limit plate, and a backward-rush preventing rubber cushion block is sleeved with the backward-rush preventing limit plate. The automobile engine suspension mounting structure is not easy to fail.

The invention discloses a railway vehicle clearance detection device and a detection method. The clearance detection device comprises a gantry frame and a moving bracket used for installing a clearance gauge. The moving frame can be driven by a driving device to do reciprocating motion along the height direction of the gantry frame. A self-coupling mechanism used for locking the moving bracket on the top of the gantry frame and a reset element used for releasing the lock are arranged between the top of the gantry frame and the moving bracket. The clearance gauge can be replaced conveniently and quickly during clearance measurement of different models of locomotives vehicles. After clearance measurement, the clearance gauge can be lifted up and reliably coupled by a mechanical device. When the device is used next time, the clearance gauge can be loosened automatically.

The invention relates to a hot-line installation type conductor auxiliary equipment suspension device, which consists of an elbow (1), a connecting plate (2), a bottom plate (3), an arc-shaped press plate (4), a screw rod (5) and a hanging ring (6), wherein the elbow (1) is connected with the connecting plate (2) and the bottom plate (3), a screw hole is formed in the bottom plate (3), the screw rod (5) is arranged in the screw hole, the upper end of the screw rod (5) is connected with the arc-shaped press plate (4), and the lower end of the screw rod (5) is welded with the hanging ring (6). When the device is used, a plunger pin on the operation rod is inserted into the hanging ring (6), the elbow (1) is hung on a conductor, the screw rod (5) is screwed, the conductor is clamped between the elbow (1) and the bottom plate (3), two devices are arranged, and auxiliary equipment are hung on the devices. The hot-line installation type conductor auxiliary equipment suspension device has the beneficial effects that the suspension requirement of various types of conductor auxiliary equipment is met, the hot-line installation is realized, the suspension is firm, the easiness in sliding away from the original position is avoided, and the falling is avoided.

The invention discloses a current transformer polarity test rod comprising a wire hook, a middle connecting insulating rod and a test tail rod, wherein the top end of the middle connecting insulating rod is connected with the wire hook, and the bottom end of the middle connecting insulating rod is connected with the test tail rod by virtue of a fixed structure; sawteeth are arranged on the inwards bent curved surface of the wire hook, and an elastic fastener is arranged at the inlet of the wire hook and at the top end of the middle connecting insulating rod; a wire suspending locking seat is arranged on the wire hook, and a direct-current power supply circuit is arranged in the test tail rod. The middle connecting insulating rod is formed by jointing more than two hollow insulating rods by virtue of a fixed structure. According to the invention, the test rod is reliably connected with the outgoing lines of the two poles of the current transformer, and the use length of the test rod can be adjusted, and therefore, the working difficulty is reduced, the working efficiency is improved, and simultaneously, the working safety coefficient is increased.

The invention provides a device for balanced suspension of dip angle burners with double constant-force spring hangers. The device is characterized in that the device comprises a balanced hanging beam, the two constant-force spring hangers and a main burner; the main burner comprises at least two sets of dip angle burners which are sequentially arranged from top to bottom; a hanging bracket is arranged on the top of each set of dip angle burner, or a carriage is arranged at the bottom of each set of dip angle burner; the two constant-force spring hangers are arranged on a bearing beam; each of the two constant-force spring hangers is connected with the balanced hanging beam through a first connecting rod device, each of the two sides of the balanced hanging beam is connected with the hanging bracket or the carriage of the tip angle burner on the topmost side through a second connecting rod device, and the two sides of the hanging brackets or the carriages of the two adjacent sets of tip angle burners are connected through third connecting rod devices. By the adoption of the device, the entire set of dip angle burners can be reliably suspended, and the device can effectively solve the problem of differential expansion between various sets of dip angle burners.

The hanging unit for narrow tube well injecting device includes one main body, one clamping block, one sealing member, one upper flange, one pressing sleeve, one guide piece, one narrow tube and other parts. Of the hanging unit, the single ram preventer can seal the well gas pressure, the non-return valve connected to the narrow tube can prevent the reverse flow of the matters inside the well, the clamping block and the terminal screw can suspend the narrow tube in the well head reliably, the sealing member can seal the ring space between the narrow tube and the cavity of the hanging unit, and the guide piece can fix the narrow tube and the auxiliary ground hanging unit to the ground anchor. The present invention has simple and accurate operation, and reliable performance.

The invention relates to a hanging operation platform for construction of a building inclined structure column and a construction method. The hanging operation platform for construction of the building inclined structure column comprises a main basket, two auxiliary baskets movably assembled together with the main basket, a hanging mechanism and a lifting mechanism. A pass-through port for the inclined structure column to penetrate through is formed in the main basket. A U-shaped port is formed in each auxiliary basket. The two auxiliary baskets are oppositely disposed on the main basket so that the U-shaped ports of the two auxiliary baskets can form a surrounding port for surrounding the inclined structure column. The surrounding port communicates with the pass-through port. The hangingmechanism is fixed to a roof steel truss and is connected with the main basket through a steel wire rope. The lifting mechanism is disposed on the main basket and is connected with the steel wire rope. The construction method of the building inclined structure column includes the steps of forming the pass-through port for the inclined structure column to penetrate through in the hanging operationplatform, and adjusting the position of the pass-through port during construction so that the inclined structure column can pass through the pass-through port in the rising or falling process of the hanging operation platform. By means of the scheme, construction of exterior facings of structure columns of different heights and different inclination degrees can be realized.

The invention provides a shoe airing hanging rack comprising a cross rack, a clamp, a hanging hook and bottom hooks and further comprising inverted Y-shaped racks, first clamping rings and second clamping rings. The bottom end of the hanging hook is locked to the clamp after penetrating the middle portion of the cross rack; the bottom end of the cross rack is provided with multiple bottom hooks; the upper end of each Y-shaped rack is provided with a hanging ring matching the bottom hooks; the two sides of each first clamping ring are provided with rotating shafts in rotatable connection with the Y-shaped racks; each first clamping ring is provided with a first opening which is in matching connection with a first nut via a first bolt; each first bolt is sleeved with a first compression spring; a plurality of first slide sleeves are arranged on each first clamping ring in a sliding manner; vertical connecting rods are fixed on the first slide sleeves; each second clamping ring is provided with a second opening which is in matching connection with a second nut via a second bolt; each second bolt is sleeved with a second compression spring. The shoe airing hanging rack is simple in structure and convenient to operate, is suitable for airing shoes of different sizes, and guarantees fixed and reliable hanging and high airing speed.

A continuous steam generator with a combustion chamber having a number of burners for fossil fuel and an outside wall composed of steam generator pipes that are welded to each other gas-tight is provided. A vertical gas flue is connected downstream of the combustion chamber on the hot gas side in an upper area via a horizontal gas flue, wherein a part of the outside wall facing the vertical gas flue and below the horizontal gas flue is inclined inward and thus forms a nose projecting into the combustion chamber with the bottom of the adjacent horizontal gas flue. Support pipes are connected downstream of at least one part of the steam generator pipes of the nose at the upper end thereof on the flow medium side, wherein the support pipes are guided substantially vertically to the lower end of the nose.

The invention relates to a suspended structure for an integrated ceiling. The suspended structure comprises a beam and a fixing rod arranged on the beam. The fixing rod is fixedly connected to the beam through a connecting part. A first penetrating hole for the fixing rod to penetrate conveniently is formed in the top end of the connecting part. A second penetrating hole for the beam to penetrate conveniently is formed in the bottom end of the connecting part. The suspended structure has the advantages that penetrating of the fixing rod is achieved by means of the first penetrating hole formed in the connecting part, penetrating of the beam is achieved by means of the second penetrating hole formed in the connecting part, the defect that due to existing screw connection, the fixing rod shakes is effectively overcome, the reliability of the fixing rod and the beam is improved in the installing process, in comparison with an existing fixing piece, the connecting part is firm for ensuing fixing and suspending, the situation that due to the fact that loads are too large, unhooking occur can be effectively prevented, the suspended structure enables the integration ceiling to be suspended more closely, and gaps between a main keel and an auxiliary keel are prevented from generating resonance.

The invention discloses a hanging packer for horizontal well multistage fracturing. The hanging packer comprises an upper connector, a central pipe and a lower connector which are sequentially connected from top to bottom; a setting mechanism, a hanging mechanism and a sealing mechanism are installed outside the central pipe in a sleeving mode; the sealing mechanism comprises a packer element; the hanging mechanism comprise an upper slip and a lower slip installed on the central pipe in a sleeving mode, and the thread angle direction of the upper slip and the thread angle direction of the lower slip is different; the setting mechanism is located under the lower slip and comprises a lock ring, a lock ring sleeve and a piston, the lock ring, the lock ring sleeve, the central pipe and the lower connector form a piston cavity, the piston is installed in the piston cavity, the lock ring and the lock ring sleeve are located over the piston, a pressure transmitting hole communicated with the piston cavity is formed in the central pipe, and the pressure transmitting hole is located under the piston. The hanging packer is high in work sealing pressure, large in hanging load, reliable in setting and hanging and low in operation risk.

The invention discloses a chain hoist, which belongs to the technical field of hoisting device design and includes an upper hook, a spring buckle, a sprocket box, a hand chain, a fixing seat, a lower hook, a card seat, a scroll spring, a round Holes, clips, and upper hooks are fixed on the top of the sprocket box. The whole device can be suspended on the workshop truss by the upper hook. The sprocket box is composed of two cavities. There are round holes processed, and the two cavities of the sprocket box are fixed through the round holes with connectors. The sprocket wheel winding the hand chain is installed in the sprocket box. The sprocket shaft is supported on the box body of the sprocket box. The bottom is fixed with a fixed seat, and the lower hook is installed on the fixed seat. The chain hoist disclosed by the present invention has the advantages of simple structure, convenient operation, low cost, good safety, good lifting stability, strong bearing capacity and long service life. .

The invention relates to an adjustable curved surface fire welding device, and belongs to the field of welding fire work tools. The adjustable curved surface fire welding device comprises a fire welding storage bin, fire welding plates, a fixing assembly and a hoisting assembly, wherein the fire welding storage bin comprises a bottom wall, and a front side wall, a rear side wall, a left side walland a right side wall which are arranged on the periphery of the bottom wall in a surrounding mode, a left baffle is hinged to the left side wall, a right baffle is hinged to the right side wall, thesum of the length of the left baffle and the length of the right baffle is less than the length of the fire welding storage bin, a fire welding opening for allowing welding slag to fall into the firewelding storage bin is formed between the left baffle and the right baffle, sliding grooves extending in the left-right direction are correspondingly formed in the front side wall and the rear side wall, left sliding blocks and right sliding blocks are slidably assembled inside the sliding grooves, and the left sliding blocks and the right sliding blocks are connected with the corresponding baffles through connecting rods; and the two fire welding plates are arranged and are both curved plates and connected with the corresponding sliding blocks. The adjustable curved surface fire welding device not only meets the requirement for adjustment of the fire welding range in the horizontal direction, but also meets the requirement for adjustment of the fire welding height and the fire welding space in the vertical direction, and is good in fire welding effect.

The invention discloses an electric ring chain elevator and belongs to the technical field of the design of hoisting devices. The electric ring chain elevator comprises an upper lifting hook, an upper spring buckle, a chain wheel box, a chain, a fixing base, a lower lifting hook, a lower spring buckle, a controller and a control cabinet. The upper lifting hook is fixed to the top of the chain wheel box. The whole device can be hung on a workshop truss through the upper lifting hook. A chain wheel is installed in the chain wheel box. A chain wheel shaft is supported on a box body of the chain wheel box. The chain winds across the chain wheel in an inner cavity of the chain wheel box. The lower lifting hook is fixed to the bottom of the chain. A weight is hooked by the lower lifting hook when the weight is hoisted, and the weight can be lifted to the required position by pulling the chain. The control cabinet is fixed to the front portion of the chain wheel box. According to the electric ring chain elevator, operation is convenient, the cost is low, and the safety is good; the weight is unlikely to fall in the conveying process; the upper lifting hook and the lower lifting hook are high in strength, the bearing capacity is high, the service life is long, braking is rapid, and positioning is accurate.

The invention discloses a plane air floatation workbench based on optical feedback. The plane air floatation workbench comprises a lower panel, an upper panel, an electromagnetic drive unit used for driving the upper panel, an air floatation unit used for suspending the upper panel, an infrared sensor set used for positioning and a control unit used for guiding and the upper panel to move and positioning the position where the upper panel moves. A control method comprises the following steps that an air film is generated at the bottom of the upper panel through an air flotation bearing firstly to enable the upper panel to suspend in air and to be able to freely move; then a transverse coil and a longitudinal coil are driven to work in a time division mode according to a preset movement track to enable the upper panel to quickly transversely wriggle or longitudinally wriggle; and finally infrared transceivers located in five orientations reflect infrared rays of different wave lengths to the upper panel, and the real-time position of the upper panel is determined by receiving reflected infrared image data, so that the driving time of a transverse driver and a longitudinal driver is determined, the corresponding speed of a platform is increased, and the corresponding positioning precision of the platform is improved. The plane air floatation workbench based on optical feedback is simple in structure, small in size, high in bearing capacity and positioning precision and stable and reliable in running.

The invention discloses a personal safety appliance for preventing falling in the whole process of climbing a pole for line repair. The personal safety appliance comprises a c-shaped falling prevention hook 2 with a limit function, a c-shaped opening sealing hook 3, a trapezoid spring 1 and a safe rope connecting pile, wherein left baffles 4 are inwards arranged at the front and the back of the left side of the c-shaped falling prevention hook 2 with a limit function; right baffles 5 are inwards arranged at the front and the back of the right side of the c-shaped falling prevention hook 2 with a limit function; the c-shaped opening sealing hook 3 is sleeved in the left and right baffles of the c-shaped falling prevention hook 2 with a limit function; the trapezoid spring 1 is arranged between the upper end of the c-shaped falling prevention hook 2 with a limit function and the top of the c-shaped opening sealing hook 3. According to the personal safety appliance, the opening and closing of the hooks can be realized through spring linkage by using the two superimposed c-shaped hooks, an operator climbing the pole up and down is prevented from falling from the altitude, the occurrence of falling from the pole due to slippery hand grabbing can be effective avoided, the operator is enabled to be always reliably hung on clinch nails, the safety in the climbing process can be ensured, and the personal safety appliance is a personal light-weight low-cost and efficient falling prevention appliance which is developed according to action principles and loading features of a human body in the pole climbing process.

The invention provides a fast-assembled construction platform based on a bridge anti-collision wall, and the platform comprises an inner side positioning part and a cantilever part; the inner side positioning part comprises a first inner side sub-positioning part, a second inner side sub-positioning part and a second hydraulic rod which are hinged with one another, and the first inner side sub-positioning part is of a right-angled trapezoidal plate body structure which can be flatly placed on a bridge, and the inclined surface is arranged towards one side of the anti-collision wall; the surface of the side, facing the anti-collision wall, of the second inner side sub-positioning piece can be attached to the inner surface of the anti-collision wall; the surface of the side, facing the anti-collision wall, of the cantilever part can be attached to the top face of the anti-collision wall, a sliding shaft is installed in the cantilever part in a sliding fit mode, and one end of the slidingshaft is inserted into a sliding hole of the cantilever part from the end, facing the inner side of the bridge, of the cantilever part and connected with the bottom of the sliding hole through an elastic element, and the other end of the spring extends out of the sliding hole and is hinged with the free end of the first hydraulic rod. The platform is simple in structure, easy to manufacture and use, safe and reliable, and does not influence traffic.