198 results about "Vertical force" patented technology

The invention discloses a multi-axial force sensor with force measuring beams with high lateral force sensitivity and strong bending resistance, the multi-axial force sensor comprises a first table body, a second table body and a plurality of force measuring beams, the force measuring beams comprise a transverse force measuring beam and a vertical force measuring beam, the vertical force measuring beam comprises two sheet-shaped vertical beam arms which are parallel to each other, and the two sheet-shaped vertical beam arms are parallel to each other. The orientation of the larger side faces of the two thin-sheet-shaped vertical beam arms is consistent with the extending direction of the two ends of the transverse force measuring beam, and the two vertical beam arms are located on the two sides of the center line of the transverse force measuring beam respectively. The thin vertical beam arms are adopted, when the thin vertical beam arms are subjected to lateral force, deformation of the vertical beam arms is large, high sensitivity of the lateral force can be obtained, meanwhile, the vertical force measuring beam adopts a double-beam form of a thin-wall structure, the two vertical beam arms are separated by a certain distance, and the two vertical beam arms bear bending moment together, so that the force measuring beam can bear large bending moment. That is to say, the force measuring beam can maintain strong bending resistance on the basis of realizing high lateral force sensitivity.

An apparatus for reducing wearer fatigue for use in a wearable safety harness system includes a dorsal chassis capable of engagement with one or more shoulder safety straps and one or more lower torso webbing straps, an attachment subassembly comprising of a D-ring, a self-retracting lifeline attachment point, lower torso webbing strap attachment point, and a force-reduction mechanism. The attachment subassembly is attached to the dorsal chassis via the force-reduction mechanism such that force-reduction mechanism absorbs vertical forces produced by the weight of a self-retracting lifeline. The force-reduction mechanism absorbs vertical forces produced by the lower torso webbing strap resulting from the attachment of tools or equipment to the lower torso webbing strap. The arrangement of the apparatus also promotes increased flexibility between the shoulder safety straps and the lower torso webbing straps torso safety strap, thereby reducing wearer fatigue.

An example implementation involves controlling robots with non-constant body pitch and height. The implementation involves obtaining a model of the robot that represents the robot as a first point mass rigidly coupled with a second point mass along a longitudinal axis. The implementation also involves determining a state of a first pair of legs, and determining a height of the first point mass based on the model and the state of the first pair of legs. The implementation further involves determining a first amount of vertical force for at least one leg of the first pair of legs to apply along a vertical axis against a surface while the at least one leg is in contact with the surface. Additionally, the implementation involves causing the at least one leg of the first pair of legs to begin applying the amount of vertical force against the surface.

This utility model discloses a fabric take-up mechanism for a heat setting machine, relating to fabric heat finishing equipment technology. The key technical points are: it includes a frame and a take-up roller. Two symmetrically arranged mounting brackets are rotatably connected to the frame, which also houses a first adjusting roller and a second adjusting roller. The first adjusting roller exerts a downward vertical force on the fabric, which is balanced with the fabric's tension. When the taken-up fabric becomes longer due to setting, the tension is less than the force exerted by the first adjusting roller, causing the first adjusting roller to move downwards. This moves the second adjusting roller away from the take-up roller, lengthening the fabric between the second adjusting roller and the take-up roller, thus re-tensioning the fabric and restoring the tension to balance with the force exerted by the first adjusting roller. This design allows the first and second adjusting rollers to adjust the fabric tension on the take-up roller in real time, reducing the likelihood of wrinkles appearing on the fabric.

The invention discloses a high-temperature friction testing device for a hydraulic slide valve. The device is composed of a valve element clamping module, a valve body mounting module, a vertical force applying module, a high-temperature heating module and a friction force applying module. The valve element clamping module is composed of a valve element, a valve element centering fixing column, a valve element fixing clamp, a valve element mounting rod and a mounting rod fixing shell. The valve body mounting module consists of an oil storage tank, an oil storage tank fixing plate and a valve body; the vertical force applying module comprises X, Y and Z three-axis guide rails driven by a motor, and pressure and friction force sensors; the high-temperature heating module surrounds the whole valve body and the valve core mounting part; the friction force applying module is driven by a motor to drive the oil storage tank to achieve axial movement of the valve body, and relative friction between the valve element and the valve body is achieved. The device can carry out friction tests of the hydraulic slide valve at different temperatures, realizes friction wear simulation of the hydraulic slide valve under multiple working conditions of oil environment, high temperature, pollution and the like, and provides data support for wear and degradation tests of the hydraulic slide valve.

The application belongs to the field of aero-engine performance test, and particularly relates to a coupling correction method for calibration of a multi-component force measurement system. X Y Z The method comprises the following steps: step one, when the multi-component force measurement system is calibrated, standard forces f X Y Z in X, Y and Z directions are respectively applied to the tail of a simulation test piece, and voltage output values V1, V2, V3, V4, V5 and V6 corresponding to axial force components F1 and F2, lateral force component F3 and vertical force components F4, F5 and F6 are recorded; step two, load states borne by each force component corresponding to the nozzle position are obtained; and step three, inter-plane coupling force correction is performed based on the load states borne by each force component corresponding to the nozzle position. After the coupling correction, the calibration accuracy of the multi-component force measurement system is improved from ±2% when no coupling correction is performed to better than ±1.5%.

This invention relates to a self-balancing unmanned aerial vehicle (UAV) for tunnel and cave exploration and its operating method. The UAV comprises a frame and a protective shield. The shield is a spherical cage composed of interconnected arc-shaped rings. Each arc-shaped ring has a connecting guide rail in its inner wall. The UAV is located inside the shield. Four balancing supports extend outward along the center line of each support's axis. Each balancing support has a ball at its outer end, which slides within the corresponding guide rail. If the self-balancing UAV accidentally lands, the shield contacts the ground. The UAV is suspended inside the shield by the front ends of the balancing supports and the balls. The UAV's center of gravity is at the lower end of the central frame. The vertical force of the center of gravity causes the central frame to shift towards the vertical line of the shield's center. Simultaneously, this causes the balancing supports and their front-end balls to slide along the guide rails towards a horizontal state parallel to the shield's diameter plane, thus placing the UAV horizontally within the shield. This invention enables the UAV to maintain self-balancing in unexpected situations or in harsh, uneven terrain, allowing it to retake off and conduct exploration without collisions.

The invention relates to a Tripteron-type parallel manipulator configured to provide three purely translational degrees of freedom by means of three orthogonal linear actuators and their respective parallelogram-shaped kinematic chains. The system incorporates an auxiliary active support arranged on the Z-axis, intended to apply an upward vertical force to the moving platform (11) in order to reduce the load borne by the kinematic chain and the main Z-axis actuator. This support can be implemented using electric or pneumatic actuators, elastic elements, or cable-driven mechanisms, allowing for active, passive, or semi-active operating modes.The integration of the auxiliary support increases the manipulator's load capacity, improves its dynamic stability, and reduces the mechanical demands on the vertical actuator, while maintaining the purely translational kinematics and structural characteristics of the original Tripteron unchanged.

The invention discloses an assembly type pile structure quasi-static test system and device. The assembly type pile structure quasi-static test system comprises a model box arranged on one side of a reaction wall. The pile structure model inserted into the inner side of the model box comprises a model main body, a model seat, a left insertion column and a right insertion column which are of an integrated structure, and the left insertion column and the right insertion column are both inserted into soil on the inner side of the model box; according to the fabricated pile structure quasi-static test system and device, by designing a rotary quick connection structure between the vertical force loading cross beams of the model, the stability of the vertical force loading cross beams above is effectively improved, displacement and falling of the cross beams in the test process are avoided, stable proceeding of the test is guaranteed, and the test efficiency is improved. Meanwhile, the subsequent rapid disassembly and assembly of the vertical force loading cross beam are facilitated, and the test convenience is improved; and an auxiliary limiting structure is designed between the rubber support and the model, so that the stability of the rubber support in a test is ensured, and a reliable basic supporting condition is provided for the test.

The invention discloses an angle-adjustable sensor test and compensation method and a test device, and the method comprises the steps: controlling an angle adjustment platform which carries a sensor to change the posture according to a preset angle sequence, exerting a constant vertical force under each posture, and synchronously collecting an output signal; based on mechanical decomposition and signal analysis, an accurate cross sensitivity coefficient and a directional symmetry parameter are obtained through calculation. The problem that the sensor performance degradation caused by the actual installation inclination angle of the sensor is difficult to quantitatively evaluate is solved. And the effects of testing and accurately quantifying the key performance of the sensor under the inclined mounting condition at low cost and high efficiency are achieved.

The utility model relates to the technical field of aircraft landing gears, in particular to a damping mechanism for a main landing gear of a light aircraft, which comprises a landing gear, aircraft wheels, a connecting rod, a vertical damper and the like. The undercarriage is composed of two supporting frames in bilateral symmetry, the left supporting frame and the right supporting frame are in transverse sliding connection through a middle sliding rail, vertical shock absorbers are symmetrically arranged in the rear side of the undercarriage, and each vertical shock absorber is composed of a fixed end, a movable end and a spring. After the airplane wheels are in contact with the ground, pressure is applied to the vertical shock absorbers through the connecting rods, springs of the vertical shock absorbers deform, meanwhile, the connecting rods rotate, accordingly, the oblique shock absorbers are driven to move downwards through the kidney-shaped grooves, springs of the oblique shock absorbers deform, and therefore the airplane wheels are driven to move downwards. Through cooperation of the vertical shock absorbers and the inclined shock absorbers, vertical force and inclined force generated when an aircraft slides can be effectively decomposed and absorbed, the shock absorption effect is optimized, the stability of the undercarriage is improved, and the stable posture of the aircraft on the ground is ensured.

The invention relates to a variable damping-variable rigidity-based crankshaft grinding force measuring device for an aviation unmanned aerial vehicle, which comprises a base and an upper computer used for processing a grinding force detection signal and calculating and outputting a damping-rigidity adjusting parameter, and is characterized in that an aviation unmanned aerial vehicle crankshaft is arranged on the base; a vertical force measuring device used for detecting the grinding force of the grinding wheel in the vertical direction and a horizontal force measuring device used for detecting the grinding force of the grinding wheel in the horizontal direction are arranged on the side portion of the aviation unmanned aerial vehicle crankshaft, and the arrangement direction of the vertical force measuring device is perpendicular to the horizontal force measuring device. The magneto-rheological damping unit and the electromagnetic rigidity unit are integrated in the vertical force measuring device and the horizontal force measuring device, the coil current is adjusted in real time through the upper computer to achieve self-adaptive adjustment of damping and rigidity, the inherent frequency of the measuring device can be changed according to the high-speed dynamic change of grinding force, resonance with a grinding system is avoided, and the measuring precision is improved. Dynamic characteristics of the device are effectively improved and response time is shortened.

The application discloses a landing gear turning moment and three-way force independent testing device based on bearing decoupling, and relates to the technical field of aerospace testing equipment. The vertical loading mechanism applies a vertical force to the landing gear to be measured through the mobile bearing assembly; the landing gear to be measured is controlled to rotate; and the decoupling force measuring assembly is used for measuring the turning torque, horizontal lateral force and longitudinal force of the landing gear. The application decouples force and moment through a pure physical level, perfectly balances the measurement accuracy and range, and has high equipment reliability.

The utility model relates to a kind of aerated concrete platform lifting structure of board breaking machine, including breaking frame, the platform lifting structure for controlling gripper lifting is provided on breaking frame, the platform lifting structure includes the connecting bracket installed on breaking frame, the bottom of the connecting bracket is fixedly connected with trapezoidal block.The aerated concrete platform lifting structure of board breaking machine, the slope surface of extrusion block is matched with the slope of trapezoidal block, the horizontal force output by oil cylinder is converted into vertical force for pushing trapezoidal block to rise, avoid oil cylinder directly bearing aerated concrete vertical gravity and bonding force, so that oil cylinder mainly bears horizontal force, reduce axial stress, avoid oil cylinder long-term high frequency bearing axial force leading to plastic deformation, and gear and two center-symmetrical profiled rack meshing, ensure that two extrusion blocks are synchronously close or far away, so that trapezoidal block is evenly stressed, and lifting is stable, and then the service life of equipment is lengthened.

The invention discloses an ultrathin integral two-component sensor system, and relates to the technical field of two-component sensors, the ultrathin integral two-component sensor system comprises a base, the upper end of the base is provided with a rectangular groove, the bottom end of the rectangular groove is provided with four butterfly-shaped diaphragm plate elastic bodies, the butterfly-shaped diaphragm plate elastic bodies are all provided with bosses, and the bosses are provided with through holes. Four butterfly-shaped template patch areas are arranged at the bottom end of the base, vertical force resistance strain gauges are installed in the four butterfly-shaped template patch areas, horizontal force double-shear-force elastomers are arranged at the two ends of the rectangular groove, blind hole patch webs are arranged at the front portion and the rear portion of the upper end of the base on the two sides of the rectangular groove, and four back face blind holes are formed in the bottom end of the base. And horizontal force resistance strain gauges are mounted in the four back blind holes. Through the integrated design of integrating the horizontal force sensor elastic body and the vertical force sensor elastic body of the high-speed rail into a whole, accumulated assembly errors between the sensor and dispersed components of the sensor are reduced, and the reliability of the sensor serving as metering and detecting equipment is improved.

The utility model provides a VHMT combined load loading device which can independently apply a vertical load, a horizontal load, a bending moment, a torque and any combined load of the loads. The VHMT combined load loading device comprises a support frame and a loading unit arranged in the support frame, the loading unit comprises a vertical and bending moment loading module, a horizontal loading module, a torque loading module and a spherical hinge module; the horizontal loading module is connected with the vertical and bending moment loading module and is used for applying horizontal force; the vertical and bending moment loading module is connected with the torque loading module through a spherical hinge module, and the spherical hinge module is used for transmitting bending moment and force downwards and isolating torque at the same time; the vertical and bending moment loading module is used for applying vertical force and bending moment; the torque loading module is used for applying torque.

This invention relates to a data acquisition device for turnout straightening equipment, comprising a press, a pressure sensing component, a displacement sensing component, a display screen control, an industrial control computer, and a touch screen. The pressure sensing component is disposed on one side of the press and connected to both the press and the industrial control computer. The display screen control is connected to the industrial control computer. A touch screen is located on one side of the press. A vertical force transmission rod is located at the top of the press, and a horizontal force transmission rod is located at the bottom. A displacement sensing component is vertically disposed on one side of the vertical force transmission rod, and its bottom is connected to the vertical force transmission rod. A displacement sensing component is horizontally disposed on one side of the horizontal force transmission rod, and its front side is connected to the horizontal force transmission rod. This invention summarizes straightening experience through collected data, provides data correction and guidance for finite element simulation and on-site manual straightening, and provides a basis for achieving intelligent straightening.

The invention relates to a construction method of a large-span curved curtain wall, which comprises the following steps: providing a plurality of vertical stress steel cables and vertical stable steel cables, and arranging a plurality of flat clamps on the vertical stress steel cables and the vertical stable steel cables at intervals, the vertical stress steel cable and the vertical stable steel cable are tied between the construction ground and the top of the building body, and the vertical stable steel cable is located between the building body and the vertical stress steel cable; a plurality of transverse stable steel cables and transverse curved steel cables are provided, the transverse stable steel cables and the transverse curved steel cables are tied to the two opposite ends of the building body, and the transverse stable steel cables are arranged in the flat plate clamps of the vertical stress steel cables in a penetrating mode; the transverse bent arc steel cable is arranged in a flat plate clamp of the vertical stable steel cable in a penetrating mode; a plurality of steel cable supporting rods with different lengths are provided, and the steel cable supporting rods are arranged between the oppositely-arranged flat plate clamps according to the site construction requirements, so that the transverse stable steel cables are arranged in a certain radian; a curtain wall support is provided, the curtain wall support is fixedly installed on the flat plate clamp of the transverse stabilizing steel cable, and a curtain wall plate is fixedly installed on the curtain wall support.

This application relates to the field of rail straightening equipment, and provides an intelligent rail weld straightening machine, including a machine frame, a laser measurement system, and a straightening force application system. The laser measurement system includes a horizontally sliding walking unit. The straightening force application system includes a first vertical force application mechanism located on the moving path of the walking unit. The first vertical force application mechanism includes a first hydraulic cylinder and a force application column. The first hydraulic cylinder is fixed to an upper moving platform, and the force application column is rotatably connected to the movable end of the first hydraulic cylinder via a rotating mechanism. A swing block is provided on the outer side of the rotating mechanism, and a limiting protrusion is provided on the free end of the swing block. A limiting groove is provided on the outer side of the force application column to fit into the limiting protrusion. When the force application column is in an upward rotating state, the limiting protrusion is matched and locked inside the limiting groove. Based on this, the possibility of collision between the force application column and the walking unit can be reduced in the event of an unexpected power outage, and the possibility of positional displacement or even damage to the walking unit can be reduced.

The application discloses a kind of mine water spraying vehicle water tank performance verification method and device, it is related to mine vehicle tank testing technical field;The method is connected by real vehicle hinge point in the connecting frame with bottom plate with guide roller, using horizontal force simulation acceleration and deceleration impact, multiple point adjustable vertical force simulation road bumping, can be loaded alone or compound, according to actual load spectrum complete strength, rigidity and baffle arrangement rationality verification.Device includes water tank, connecting frame, bottom plate, horizontal and vertical loading mechanism, connecting frame can move along horizontal direction, vertical loading point quantity, position, force value can be adjusted.The present application can truly reproduce mine area harsh working conditions in laboratory, solve the existing problem that only rely on simulation cannot be verified in entity, test accurate, strong universality, fill the method blank of mine water tank performance verification, suitable for all kinds of mine water spraying vehicle water tank and liquid tank body reliability test.

Ladder protection system for a vertical ladder of a public or private playground equipment with a protective body enclosing the ladder at least on one side over its height and at least one pivotable flap arranged within the protective body, characterized in that the flap is pivotably mounted about a horizontal axis in a first bearing fixedly connected to the protective body and rests at the opposite end on a support element that can absorb vertical forces and allow horizontal relative movement.

This utility model discloses a weighing device and a shelf structure. The weighing device includes: a base; at least one sensor assembly mounted on the base; at least one connecting mechanism, each connecting mechanism being connected to one of the sensor assemblies; and a weighing pan disposed above the base. The weighing pan includes at least one connecting portion, which is movably connected to the connecting mechanism. The connecting portion has a connecting hole for insertion into the connecting mechanism, and a gap exists between the connecting hole and the connecting mechanism along the radial direction of the connecting hole. By providing a gap between the connecting hole and the connecting mechanism along the radial direction (i.e., laterally) of the connecting hole, this utility model's weighing device and shelf structure avoids the force exerted by the weighing pan on the connecting mechanism in the lateral direction due to weighing pan deformation. This ensures that the connecting mechanism applies only vertical force to the sensor, thereby guaranteeing the measurement accuracy of the weighing device.

This utility model relates to a positioning structure for a plate breaking machine, including a frame mounted on the plate breaking machine. The frame is equipped with several symmetrically distributed supporting shells, positioning components, pressing blocks, and feeding components. This positioning structure, by incorporating supporting shells, positioning components, and pressing blocks, with both the pressing blocks and the force-bearing blocks designed for inclined surface contact, utilizes the force decomposition characteristics of the inclined surface to convert the vertical force output by the hydraulic cylinder into the horizontal force required by the positioning plate. Furthermore, it decomposes the reaction force of the positioning plate into forces acting on the supporting shells and forces acting on the hydraulic cylinder, preventing the hydraulic cylinder from directly bearing excessive horizontal reaction force. This force direction conversion reduces the load on the hydraulic cylinder, preventing metal fatigue and malfunctions caused by prolonged operation. Moreover, the spring's rebound potential energy drives the positioning plate to automatically reset, requiring no additional power and simplifying the control logic of the release action.

A new type of pressure casting pot, including pot body and its adaptation pot cover, pot body and pot cover are equipped with flange at the joint, the left side or right side of pot cover is hinged with pot body through hinged structure, the upper and lower sides of pot body are symmetrically equipped with locking unit, locking unit includes hook plate piece and telescopic device, one side of hook plate piece can be hooked in the flange outside of joint pot cover, the other side is connected with telescopic device, the flanges of pot body and pot cover are all provided with corresponding multiple connecting holes, hook plate piece is equipped with connecting rod passing through one of connecting holes, the end of connecting rod near telescopic device is detachably connected with hook plate piece.The locking unit of the utility model is symmetrical up and down, can provide uniform locking force, the hook head is responsible for direct bearing and hooking, the L-shaped plate is responsible for force arm conversion and connection, so that the horizontal thrust from the telescopic device can be effectively converted into the vertical force of the hooking flange, two locking devices can act synchronously, it is convenient to open the pot cover slowly at the same time, and the eccentric wear and tear phenomenon of sealing ring is reduced.

This application discloses a creep testing device for a fiber composite-steel interface. The device horizontally supports the specimen using a first support and a second support. A first loading mechanism applies a downward vertical force to the specimen, with the point of application located between the first end and a pre-fabricated crack. A second loading mechanism applies a downward vertical force to the specimen, with the point of application located between the second end and the pre-fabricated crack. The fiber composite-steel beam interface of the specimen primarily bears Type II interfacial shear stress caused by bending deformation, while the Type I peel stress approaches zero. This avoids the combined stress-shear + peel stress generated by direct tension in traditional lap joints, enabling the test results to accurately reflect the interface's durability under pure shear.

A computer system and computer-implemented method for estimating lateral slip losses in a vehicle performing a manoeuvre are provided. The computer system has processing circuitry to acquire a lateral slip resistance coefficient for the vehicle, acquire parameters of the manoeuvre to be performed by the vehicle, including a vehicle speed, a vertical force on one or more axles of the vehicle, and a turning radius, and estimate lateral slip losses for the vehicle based on the acquired lateral slip resistance coefficient and the acquired parameters of the manoeuvre.

The utility model provides a highway construction side slope protection net anchoring structure, including anchoring nail body, sliding cylinder, clamping peg, first sliding rod, second sliding rod and third sliding rod, and the sliding cylinder opens in the anchoring nail body, and both sides of anchoring nail body open have clamping hole, and the clamping peg slides in the clamping hole, and the first sliding rod slides in the sliding cylinder, and the second sliding rod is fixed on the first sliding rod, and the third sliding rod is fixed on the second sliding rod, and the first sliding rod and third sliding rod are all cylindrical, and the radius of first sliding rod is less than third sliding rod, and the second sliding rod is circular table, because the utility model has installed the clamping peg on both sides of anchoring nail body, and the user installs anchoring nail after, can through extruding clamping peg, and it is stuck into the inside of side slope, through the spacing of clamping peg and the inside of side slope, can effectively resist the vertical force of rockfall, improve the stability of anchoring, reduce the potential safety hazard.

The utility model belongs to the technical field of photovoltaic supports, and discloses a mountain cable structure photovoltaic support steel strand anchoring device which comprises a middle stand column, a U-shaped bolt, an anchor head and a steel strand. The middle stand column is vertically arranged on the mountain slope and is parallel to the normal direction of the horizontal plane. The U-shaped bolt is fixedly arranged at the top of the middle stand column; the anchor head is arranged on one side of the U-shaped bolt, the steel strand sequentially penetrates through the U-shaped bolt and the anchor head, and the anchor head is used for adjusting the tensioning force of the steel strand. According to the mountain cable structure photovoltaic support, the middle stand column is vertically arranged instead of being perpendicular to the mountain slope, construction precision and efficiency are improved, and the mountain cable structure photovoltaic support adapts to complex terrains. The steel strand is accurately anchored through the anchor head, it is ensured that resultant force is vertically downward, and structural stability and safety are enhanced. The middle stand columns share part of vertical force originally borne by the end stand columns, stress distribution is optimized, the engineering amount of the end stand columns is reduced, cost is reduced, and economical efficiency and sustainability are improved.

A motion generation apparatus (1000); (2000) for a motion platform system has a plurality of motion control arrangements (1201), (1202), (1203) that include control members (1211), (1212), (1213) and couplings (1241), (1242), (1243) configured to engage respective inclined portions (1251), (1252), (1253) of the control members. Laterally driving the or each respective control member forces the or each respective coupling in a direction along an inclined path P1, P2, P3 to impart a vertical force to a portion (1801), (1802), (1803) of a motion platform (1800). Motion and positioning of the platform (1800) is determined by the combined movement and / or positioning of the control members (1211), (1212), (1213).

The utility model relates to the technical field of advertising light box, solved only to the horizontal position of advertising light box positioning, when the vertical force impact of advertising light box, it will easily because of the force and the problem of the longitudinal position deviation. Concretely be a kind of advertising light box mounting structure, including telescopic frame, the both sides of the surface of telescopic frame are all provided with mounting slot, the inside of mounting slot is clamped and is connected with positioning column, the one end of positioning column is fixedly installed with positioning plate, the both sides of telescopic frame inside are all fixedly installed with positioning assembly, the inside of telescopic frame is clamped with light box, the back of telescopic frame is fixedly installed with support frame, the positioning assembly includes the thread groove being provided in the both sides of telescopic frame inside, the inside screw thread of thread groove is connected with threaded rod, the one end of threaded rod is rotatably connected with clamping plate, the surface of clamping plate is provided with embedding groove, the inside of embedding groove is fixedly installed with antiskid pad.