250results about How to "High leveling accuracy" patented technology

The invention discloses a precise leveling system of a vibration isolation foundation bed. The lower bottom surface of the vibration isolation foundation bed is supported by air springs; a precise optical vibration isolation platform is arranged on the vibration isolation foundation bed; one or two level monitors are arranged on the precise optical vibration isolation platform for measuring an included angle between the vibration isolation platform and the absolute level in two mutually vertical directions; flexible leg monitoring devices are respectively connected with the own air springs; the output ends of the level monitors and the flexible leg monitoring devices are respectively connected with the input ends of controllers; the output ends of the controllers are connected with all control valves; an air channel port of each control valve is respectively connected with the own air spring; air supplying devices respectively supply air for each control valve. The precise leveling system realizes vibration isolation of Grade II; the vibration isolation platform has highly precise planarity and meets requirements of various precision instruments for the environment; the control valves realize the air inflow of a small amount during the charging process of the air springs, improve leveling precision and can keep the system stable. The precise leveling system is applicable to ultra precise measurement and processing.

An exposure apparatus and an exposure method that minimize the range over which exposing light becomes defocused even when a non-level portion is present within each shot are provided. One shot is selected from a plurality of shots (exposure unit areas) set on a wafer (S 50). 49 measurement points are set in the selected shot and the three-dimensional coordinates of each measurement point are determined (S 70). Next, an arithmetic operation is performed using the 49 sets of three-dimensional coordinate data to ascertain an "in-shot focus plane" (S 90). This arithmetic operation may be performed through, for instance, the method of least squares. The extents of positional deviation between the surface of the selected shot and the in-shot focus plane is ascertained and the extents of deviation are stored in memory as "adjustment values" (S 110). An exposure shot to undergo exposure processing is selected and the surface level variation manifesting at the exposure shot is measured. The adjustment values are subtracted from the results of the measurement and exposing light is irradiated on the exposure shot while moving the wafer along the vertical direction in conformance to the result of the subtraction (S 130).

The invention discloses a leveling method based on four-point support and an electromechanical automatic leveling system. In the leveling method, a symmetrical diagonal lifting and leveling strategy is adopted, and the leveling purpose is achieved mainly by regulating the levelness of the ligatures among supporting points on diagonal lines; and the leveling system comprises a central processor, a level sensor, a control keyboard, a display, four alternating-current servo drivers and four supporting legs; and each supporting leg comprises a motor, a speed reducer, a ball screw and a base. The invention is particularly suitable for large-medium-sized radar truck vehicle-mounted platforms, communication vehicles and various engineering vehicles for engineering machinery, the method has the advantages of high leveling efficiency, high leveling reliability and the like, and the leveling system has the advantages of high leveling precision, high intelligent degree, high speed, strong carrying capacity, good stability, high transmission efficiency, suitability for severe environments and the like.

The present invention relates to a level indicator for determining the level of liquid in a container, the level indicator comprising: a floating device comprising a metal; a transmitter arranged to transmit an electromagnetic signal towards the floating device; and a receiver arranged to receive a response signal from the floating device. The floating device is moveable relative to the receiver so that a distance from the floating device to the receiver is altered in response to an altered level of liquid in the container, and wherein the electrical signal is a function of at least said distance. The receiver is electrically connectable to a control unit configurable to determine a position of the floating device relative to the receiver based on the electrical signal. The invention also relates to a system and a tank comprising the level indicator.

The invention discloses a multi-shaft support air floatation platform leveling method and belongs to the technical field of ultraprecise apparatus platforms. The multi-shaft support air floatation platform leveling method aims to solve the problem that existing support platforms are limited in leveling conditions and narrow in application range. The method includes that: an upper computer transmits a current working mode, a control command and an error parameter to a controller via the Ethernet; the controller transmits servo period starting signals for every 200microseconds to start a moving state working mode or a static state working mode; the controller performs data fusion on all feedback signals read by the same so as to acquire regulating amount of support legs, corrects driving signals of a servo voice coil motor by means of driving a servo voice coil motor driver, judges whether a bearing platform is in static state or not and whether levelness of the bearing platform reaches to a preset precision range or not, and if so, finishes the current servo period leveling and waits for the next servo period till all servo periods are finished. The multi-shaft support air floatation platform leveling method is used for leveling of the air floatation platform.

The invention provides an adjustable leveling guide rail. The adjustable leveling guide rail comprises a guide rail beam and a plurality of supporting pieces, wherein each supporting piece comprises a screw rod and a nut; the screw rod is connected with the guide rail beam through the nut; the end part of the screw rod is provided with a fixing block which is hexagonal, tetragonal or triangular; the fixing block is connected with the screw rod in an integral molding mode or the fixing block is detachably connected with the screw rod; and the supporting piece also comprises a positioning piece connected with the screw rod in a fitting mode. The invention also provides a leveling method for realizing the leveling guide rail, namely, the levelness of the leveling guide rail is adjusted by rotating a leveling nut and a positioning nut. In a construction process, instant leveling is realized by clamping the fixing block, fixing the screw rod and adjusting the levelness of the guide rail by screwing the positioning nut and the adjusting nut respectively. The adjustable leveling guide rail has high leveling accuracy, can realize instant leveling in the construction process and has the advantages of low cost, convenient detachment, easy construction, clean environment, green construction and the like.

The invention relates to an electric automatic levelling brace for realizing multipoint electric automatic levelling, and aims to provide an electric automatic levelling brace with large lifting weight, rapid and reliable touchdown, good repeatability of levelling precision, high precision, safety, convenience, convenient maintenance and simple electric connection. The electric automatic levelling brace comprises a levelling bearing disc connected with a levelling brace cylinder body and a direct current servo motor with an electric control unit. The top of the levelling brace cylinder body is provided with a transmission chain which is connected with an output shaft of a speed reducer and a leading screw pair for rotary motion; the leading screw pair drives a levelling telescopic cylinder body manufactured with a screw and the levelling bearing disc fixedly connected with the leading screw pair together to do linear lifting motion; a microswitch for feeding back the lifting position to an external control system is arranged on the cylinder wall of the levelling brace cylinder body; a small displacement triggering shaft records the moving position, triggers the microswitch at a triggering point and transfers an electrical signal of the lifting position of the levelling brace to the outside; and the small displacement triggering shaft is connected external control equipment through the microswitch and forms a closed loop levelling system with the servo motor connected with the speed reducer .

The invention belongs to the technical field that when a vehicle runs with specific actions or under specific conditions or being operated by a driver, the responsivity is adopted as the feature and discloses a large-size vehicle body automatic leveling system and method based on six-point support. The large-size vehicle body automatic leveling system comprises a controller, a double-shaft tilt angle sensor, a human-computer interface, an alarm device, six support legs, six direct current motor drivers and six Hall sensors. By means of the large-size vehicle body automatic leveling system, thehighest point in a leveling support leg is maintained to be unchanged, remaining support points move upwards synchronously to be aligned with the highest point, and when all the remaining points reach the position of the highest point, a vehicle body is in the horizontal state; at the force adjustment stage, it is guaranteed that all tyres leave the ground and do not play the support role, and the whole vehicle body is supported by the six support legs; meanwhile, fine adjustment is conducted, and it is guaranteed that the six support legs are stressed uniformly. By means of the large-size vehicle body automatic leveling system, automatic leveling of a platform can be achieved in an outdoor unstructured environment; and the system has the advantages of being high in leveling precision, speed and reliability, great in stability and the like and is particularly applicable to the electronic equipment vehicle-mounted platform or various campsite motor homes.

The invention provides a foundation leveling device, a foundation assembly and a foundation forming method for a wind driven generator tower. The leveling device comprises at least three anchoring bolts and fine adjusting nuts, upper and lower anchor plates which are horizontally arranged, at least three brackets and rough adjusting nuts; the upper anchor plate is sleeved at the upper ends of the anchoring bolts and is used for being fixedly connected with a tower flange plate; the lower anchor plate is sleeved at the lower ends of the anchoring bolts and is used for being fixedly connected with the upper anchor plate; the fine adjusting nuts are respectively sleeved on the corresponding anchoring bolts and are abutted against the lower surface of the upper anchor plate; the brackets are arranged below the lower anchor plate; the brackets are used for supporting and fixing the lower anchor plate by rough adjusting bolts; and the rough adjusting nuts are respectively sleeved on the corresponding rough adjusting bolts and are abutted against the lower surface of the lower anchor plate. According to the foundation leveling device, the foundation assembly and the foundation forming method for the wind driven generator tower, which are provided by the invention, the defects of fuzzy installing process, low accuracy and high cost of an existing foundation leveling device are overcome; the installing process is simplified; and the cost is saved.

The invention discloses an automatic horizontal adjusting device and adjusting method for platform. The automatic horizontal adjusting device for the platform comprises a bedplate, wherein an air spring is mounted under each corner of the bedplate, the air springs are connected with the upper ends of lifting mechanisms mounted in support legs, the lower ends of the lifting mechanisms are connected with transmission devices, a base is arranged under the support legs, a support seat A is mounted in the middle position under the bedplate, adjusting gas valves are also fixedly mounted under the bedplate, the adjusting gas valves are connected with the air springs through gas pipes, one end of a swing rod is provided with a spherical head A and is fixed by a clamp sleeve sleeved on the exterior of the support seat A, the other end of the swing rod is provided with a plumb bob, a suspension arm is mounted on the rod body of the swing rod, the end head of the suspension arm is correspondingly positioned under contact points of the adjusting gas valves, a locking plate is fixedly arranged on the base, and a movable magnet block inside the plumb bob controls the locking through a remote control switch. The invention also provides the horizontal adjusting method for the platform, and the horizontal adjusting device and the adjusting method have the characteristics that the horizontal adjusting time is short, the horizontal adjusting accuracy is high, the reliability is high and the like.

The invention discloses a measurement and monitoring method for centroid skewing permitted interference of a multi-axis support air floating platform and belongs to the technical field of an ultra-precise apparatus platform. The invention solves the problem that an existing support platform is limited in leveling state and is narrow in the range of application. The measurement and monitoring method comprises the steps that a centroid offset threshold is firstly set, a centroid offset G (x0, y0) is compared with the centroid offset threshold, and when the centroid offset G (x0, y0) is less than the centroid offset threshold, the telescopic length of each support leg is compensated; when the centroid offset G (x0, y0) is greater than the centroid offset threshold, nozzles of air feet are controlled to spray air, so as to enable a chassis platform to carry out translational motion in a horizontal concrete foundation and move along with the load on the chassis platform, so that the relative offset (x2, y2) is adjusted until the centroid offset G (x0, y0) is adjusted to be in the range of the centroid offset threshold. The measurement and monitoring method for centroid skewing permitted interference of the multi-axis support air floating platform is applicable to the measurement and monitoring of centroid skewing permitted interference of air floating platforms.

The invention discloses a tripod capable of being fast leveled. The tripod comprises a base, three supporting legs and a leveling fixed seat, each supporting leg comprises a sliding seat and a sliding rod, a locking knob is fixedly arranged on each sliding seat, the fixed supporting legs are connected with the base through the locking knobs, and supporting feet are arranged at the ends, away from the sliding seats, of the sliding rods. Precision adjusting mechanisms are arranged between the sliding seats and the sliding rods, and the length of the supporting legs can be precisely adjusted through the precision adjusting mechanisms. The leveling fixed seat is arranged on the base and comprises an equipment mounting seat, a linkage fixed plate and a plurality of leveling knobs, measuring equipment is arranged on the equipment mounting seat, the leveling knobs are arranged on the lower portion of the equipment mounting seat and used for precisely adjusting the flatness of the equipment mounting seat, and the linkage fixed plate is clamped on the leveling knobs. The tripod has three adjusting methods of rough adjusting, precise adjusting and fine adjusting, the tripod can be unfolded, leveled, dismounted and stored fast, the leveling precision of the tripod is high, the leveling error can be controlled within 20 degrees, the precision stability is high in the long-term work process, and the precision stability is slightly influenced by environment temperature changes.

The invention relates to a hydropress with bidirectional couple levelling function, comprising an upper separator, four supports, lower separators, master cylinders and lateral cylinders, wherein a slider is connected with the master cylinders and the lateral cylinders. The hydropress is characterized in that levelling cylinders are fixedly installed on the upper and lower parts of each support; piston rods of the levelling cylinders are connected with the upper and lower ends of the four corners of the slider; levelling cylinders at the upper ends of the four corners of the slider form a torque group capable of applying couples with equal magnitude and opposite directions with levelling cylinders at the lower ends of the diagonals of the slider; and displacement sensors are also arranged at the four corners of the slider. The hydropress has the following advantages: the hydropress realizes levelling the press slider by utilizing the bidirectional couple levelling principle, thus not only shortening the levelling response time and improving the slider levelling precision and press production efficiency, but also avoiding loss of the main tonnage of the hydropress, substantially saving energy and lowering the production cost.

The invention provides an automatic leveling and adjusting lifting appliance and a control method thereof. The lifting appliance comprises the main technical characteristics that: a y-axis guide rail arranged on the upper part of a frame is provided with a sliding device which moves a lifting device in an x axis, and a y-axis driving mechanism of the sliding device; a lifting device is arranged on the upper part of the sliding device; the frame is also provided with an inclination sensor, a system controller and a drive motor circuit device; and the system controller reads inclination data sent by the inclination sensor, carries out calculation according to the read inclination data, and outputs a control signal required by leveling and adjusting the lifting appliance to the drive motor circuit device so as to drive an X-axis motor and a Y-axis motor to do cyclic action until the inclination data read by the system controller meets the requirements of leveling and adjusting. The lifting appliance and the control method thereof have the advantages of high automation degree, accurate leveling and adjusting, convenient operation and flexible use.

The invention relates to a heavy-duty isothermal forging hydraulic press, which comprises an upper transverse beam, a lower transverse beam, upright posts, a main cylinder, side cylinders and a slide block, wherein an upper baseplate is fixed on the lower plane of the slide block; and a movable workbench is arranged on the lower transverse beam. The heavy-duty isothermal forging hydraulic press is characterized in that the upper transverse beam and the lower transverse beam form a combined beam body structure; leveling cylinders are fixed on the four corners of the upper end of the upper transverse beam and the upper end of the lower transverse beam; each leveling cylinder is provided with an independent leveling control system; an upper knock-out device is arranged on the slide block; movable workbench positioning mechanisms are arranged on the lower part of the movable workbench body and in the lower transverse beam; and the movable workbench body is further provided with a movable workbench clamping device. The heavy-duty isothermal forging hydraulic press is characterized in that a combined transverse beam is light in weight and is convenient to transport and produce, and the manufacturing cost can be reduced; a leveling effect is achieved via the leveling cylinders, the leveling response time is shortened, and energy is saved greatly; through the upper knock-out device, successful demolding of workpieces can be realized, and the workpiece forging and pressing quality is ensured; and accurate positioning and stable running of a press workbench can be realized, and the production requirement of forging equipment for heavy-duty aviation forgings is met.

The invention relates to a hydraulic four-point leveling method with accuracy less than 1 minute. The hydraulic four-point leveling method with the accuracy less than 1 minute is characterized in that according to different conditions of insufficient car body rigidity and sufficient car body rigidity, firstly, four legs are laid on the ground and absolute values of a transverse shaft and a vertical shaft of a precise sensor are adjusted to 900 seconds based on the foundation. A precise leveling is conducted after a rough leveling is finished. The leveling adopts a method of a low point being aligned to a high point so that a lift leveling is achieved. Proportion integration differentiation (PID) operation is conducted towards a tilt error of the transverse shaft and the vertical shaft of the precise sensor, control is conducted after a controlled quantity of lifting legs is calculated. In the process of PID, an integration element overcomes a proportional valve dead zone and a differentiation element restrains continuous increase of a leveling speed. Compared with the prior art, the hydraulic four-point leveling method with the accuracy less than 1 minute is high in leveling accuracy, reasonable in arrangement of the transverse shaft and the vertical shaft leveling order, capable of overcoming direction deflection caused by the insufficient car body rigidity, various in leveling methods and capable of choosing different modes according to different car body structures.

The invention discloses a hydraulic automatic leveling method of a ladle car and the leveling system thereof. Firstly the leveling system is divided into an X direction and a Y direction according to the car body plane and is equipped with two tilt sensors corresponding to the X direction and the Y direction, and four groups of suspension oil cylinders and position sensors corresponding to the four groups of suspension oil cylinders are arranged between the tyre and the car body on the ladle car; a controlling unit picks up the horizontal position signals of the car body and the position signals of the suspension oil cylinders in real time through the circulation of the tilt sensors and the position sensors, the highest supporting point of the car body at certain moment is judged by the inclination angle value, and the distance difference of the other three points and the highest point is calculated through the size of the inclination angle and the actual physical distance of the four groups of suspension oil cylinders in the X direction and in the Y direction; the highest point is taken as the reference point and keeps unchanged, and the other three points are adjusted to approach the highest point through controlling the fluctuation of the suspension oil cylinders according to only rising without descending method, until the car body is up to the level position. The invention can automatically adjust the car body posture of the ladle car according to the actual condition during the driving process, thereby avoiding the condition of inclination or center deviation.

The invention relates to a radar digital platform leveling device and method. The leveling method comprises the following steps of sensing the attitude of a vehicle body and a coordinate conversion digital platform by utilizing an attitude angle sensing system to establish a digital platform; calculating the value of an antenna azimuth code salver, the value of an antenna pitch code salver and a transverse rolling angle formed between an antenna array surface X axis and a horizontal plane which are parallel to each other during the working process of a radar; and driving an antenna to the appointed position, the pitch position and the antenna X axis attitude position to realize the radar leveling function. The leveling device comprises an attitude angle sensing system, an antenna drive control system and an antenna leveling mechanism. The attitude angle sensing system is used for sensing a transverse inclination angle and a longitudinal inclination angle of the prior vehicle body as well as an included angle formed between a reference axis of the longitudinal inclination attitude angle and the north direction; the antenna drive control system is used for converting the antenna to the appointed direction through the azimuth code salver and an azimuth driving mechanism; a supporting back frame of the antenna is pushed to rotate by a pitch driving mechanism and the pitch code salver, so that the antenna reaches an appointed pitch angle; the antenna leveling mechanism is used for pushing the antenna to carry out one-dimensional rotation around a ball bearing, so that an X axisin an antenna array surface rectangular coordinate system is parallel to the horizontal plane, thereby the leveling of the radar is finished.

Disclosed is an X-ray imaging device, the device including: an X-ray radiation unit for radiating X-rays to the predetermined target areas of an object to be imaged in respective imaging positions; an X-ray sensing unit for receiving the X-rays; a movement unit for arranging the X-ray radiation unit and the X-ray sensing unit to allow the X-ray radiation unit and the X-ray sensing unit to face each other in the respective imaging positions, with the object located therebetween; a position information provision unit for providing position information of the X-ray radiation unit and the X-ray sensing unit, position information of the variable rotary shaft, and position information of the target areas; a control unit for controlling the X-ray radiation unit, the X-ray sensing unit, and the movement unit; and an image processing unit for producing three-dimensional images of the object from the projection data.

The invention discloses an automatic locking and leveling system of a vehicle. The requirements of small size, low power, economical efficiency, reliability and stability of the leveling system are met, and furthermore, a leveling method matched with the leveling system is provided. The flow of each stage of leveling is adjusted through an electromagnetic valve, the problems of the judgment of grounding of hydraulic supporting legs, the judgment of the vehicle lifting height, the judgment of the stretching and retracting limit position and the like generated after a hydraulic supporting leg displacement sensor is removed are solved, so that the high-precision leveling of the vehicle or a platform is realized.

The invention relates to the technical field of biochemical sensor detection, in particular to a micro-cantilever beam piezoresistive bridge type sensor detecting instrument, which solves the problems that the traditional micro-cantilever beam piezoresistive bridge type sensor detecting instrument cannot carry out automatically zero setting or has low zero setting accuracy due to poor contact or abrasion of a mechanical potentiometer, and gain values of two output ends of an inner electric bridge cannot be adjusted. The micro-cantilever beam piezoresistive bridge type sensor detecting instrument comprises a micro-cantilever beam piezoresistive bridge type sensor, a first differential amplifier, a filter, a voltage follower, a singlechip, a computer and an LCD (liquid crystal display); a high-speed synchronous serial port input end of a digital-to-analog converter is connected with a high-speed synchronous serial port output end of the singlechip; a voltage-dividing circuit which is formed by serially connecting a third resistor and a fourth resistor is connected between a fine-tuning signal output end of the digital-to-analog converter and the ground. The micro-cantilever beam piezoresistive bridge type sensor detecting instrument has the advantages of reasonable structure, ingenious design, small volume, low power consumption and strong universality, and can be widely suitable for biochemical detection, automobiles, meteorology and a plurality of industrial devices.

The invention provides an electrical appliance provided with self-leveling feet and an automatic leveling method. The bottom part of the electrical appliance is provided with the self-leveling feet. Each self-leveling foot comprises a driving device, a bracket, a worm, a worm wheel and an adjustment supporting rod, wherein the driving device is installed on the bracket and drives the worm to rotate, the worm is matched with the worm wheel and drives the worm wheel to rotate, the adjustment supporting rod is threaded in a hole in the bracket, the adjustment supporting rod is provided with teeth which are meshed with teeth of the worm wheel to move upward or downward, the bottom end of the adjustment supporting rod is provided with a pressure sensor, the pressure sensor and the driving device are electrically connected with a controller of the electrical appliance, the controller sends an instruction so that the pressure sensor detects pressure thereon from a ground foot supporting surface and compares the magnitude of the pressure with that of a set pressure, and if the pressure detected by the pressure sensor is within a set pressure range, the controller considers that the electrical appliance is leveled and prompts a user. The electrical appliance can realize automatic leveling, is simple and high in leveling precision, avoids the cumbersome operation of manually screwing the ground feet for leveling, and enhances the user experience.

The invention relates to a moment levelling control method for a composite press and a levelling device of the composite press. According to the moment levelling control method, four levelling hydraulic cylinders are vertically arranged on the lower sides of the four corners of a sliding block, the target levelling output force of each levelling hydraulic cylinder is controlled to act on the sliding block through a sliding mode variable structure control algorithm, so that accurate horizontal control of the sliding block is achieved, and therefore the problems that in a high-speed levelling system, the levelling efficiency is low, the levelling precision is not high, and the disturbance resisting capacity is not high are solved; and meanwhile, in the rapid press process of the press, the optimal sliding mode control algorithm based on the hyperbolic secant function improved reaching law is designed so that the optimal target output leveling force can be obtained and act on the sliding block, and horizontal control over the sliding block can be achieved as fast as possible and as stably as possible, the situation that in the levelling process, a levelling system has great impact and vibration on a main cylinder is improved, and the stability and the levelling precision of the system are improved.

The invention provides a leveling supporting leg based on a planetary roller screw. The planetary roller screw is a transmission device for converting the rotation of an external motor to linear reciprocating motion of a push rod and meanwhile converting input torque to output axial force of the push rod. The planetary roller screw comprises a nut, a plurality of rollers, a screw rod, inner tooth rings, a PTFE sealing element and an end retainer. The screw rod and the nut are coaxially mounted, the multiple rollers are uniformly arranged between the screw rod and the nut, the screw threads of the rollers make contact with the screw thread of the nut and the screw thread of the screw rod at the same time, tooth wheels of the two ends of the rollers are engaged with the inner tooth rings, the rollers perform planetary motion around the screw rod, and meanwhile, the nut is pushed to perform reciprocating motion along the axis of the screw rod. The nut and the push rod are fastened together through screws, an external spline of the external circle of the nut is matched with an internal spline of a guiding sleeve, and the nut drives the push rod to perform linear reciprocating motion. Compared with existing hydraulic leveling devices, the leveling supporting leg based on the planetary roller screw has the advantages of being high in bearing capacity, high in response speed, high in leveling precision, long in service life, convenient to maintain and the like.

The invention discloses a mobile electric-driven automatic leveling device including a mobile control console (A), four mobile supporters (E), one or two tilt angle sensors (B), and connecting cables(D); the mobile control console (A) is connected with the mobile supporters (E) and the tilt angle sensors (B) by the connecting cables (D) respectively. The inventor also discloses a leveling methodof the mobile electric-driven automatic leveling device, wherein the method includes a manual installation stage, an automatic leveling stage and a manual retreating stage. The automatic leveling stage also includes the steps of fast rising, determination of the correspondence relationship of placement directions of the mobile supporters and the tilt angle sensors, synchronous rising, coarse adjustment, fine adjustment, and 'virtual leg' detection. The device and the method have the advantages of high leveling precision, less needed time, convenient movement, simple operation, strong transportability and wide application range.

The invention discloses a hydraulic control valve. A plurality of main reversing valves on a hydraulic oil channel in parallel are integrated in the hydraulic control valve, and each main reversing valve is provided with a pilot control end and an electric control pilot device; and each electric control pilot device comprises a pilot reversing valve and a reversing cylinder, piston rods of the reversing cylinders are connected with the pilot control ends of the main reversing valves in a transmission way, and three working states can be realized. The hydraulic control valve can be controlled manually and remotely for manual and electric control operations. Due to the remote control function, the operability and the environmental adaptability of equipment can be enhanced, and the leveling accuracy as well as the mobility and the convenience in operation of the whole vehicle can be improved. In case of failure in electric control, the manual operation can be used as an emergency operation mode. The invention discloses a getting-off support leg control system of a firefighting vehicle with the hydraulic control valve.

The invention discloses an electronic balance base. The electronic balance base comprises a housing, adjustment screws, adjustment gears, driving motors, a spectrum emitter, a disc-shaped horizontal rule, a spectrum receiver, an electronic gyroscope, a control module, an adjustment button and a power supply, wherein the four corners of the base plate of the housing are each provided with a threaded hole, the upper portions of the adjustment screws are provided with gears, the lower portions of the adjustment screws are provided with threads, and the adjustment screws are arranged on the threaded holes; the driving motors, the adjustment gears and the gears of the adjustment screws are successively in transmission connection; the disc-shaped horizontal rule is arranged between the spectrum receiver and the spectrum emitter; and the electronic gyroscope is arranged at the center of the base plate of the housing. According to the electronic balance base, leveling work of the whole electronic balance base can be automatically and rapidly carried out under the control of the control module simply by pressing the adjustment button without manual intervention, and thus the work efficiency and the leveling precision are improved.

The invention discloses an automatic leveling method and leveling device for a hot bed of a 3D printer. Spatial coordinates of arbitrary three points which are not located on the same straight line onthe hot bed are measured; spatial coordinates N(x,y,z) of all points on a spatial circle determined by the three points are calculated through the algorithm of determining a circle by threepoints; the highest point M and the lowest point m on the spatial circle are determined according to the z value, and a vector Mm connecting M and m and passing through the center of the spatial circle is obtained; the included angle lambda of the vector Mm and the X axis and the half height difference H of the vector Mm in the Z axis direction are calculated; the hot bed is driven to rotate bythe angle lambda along a vertical rotating shaft perpendicular to the XOY plane, and a horizontal rotating shaft is driven to drive the hot bed to swing by the height H; and the steps are repeated till measured H meet the precision requirement. According to the leveling method and the leveling device, automatic detection and leveling of the hot bed of the 3D printer can be achieved, and the quality of a 3D printed product is improved.

The invention discloses a chassis leveling system for a mixture arm high-altitude operation vehicle. Vertical oil cylinders and horizontal oil cylinders are communicated with an oil tank through an eight-connected electromagnetic reversing valve, an overflow valve and speed control valves, and a double-shaft tilt sensor is installed on an auxiliary frame; horizontal extend-in-place detecting switches are installed on the side faces of supporting leg boxes of the auxiliary frame respectively, horizontal extract-in-place detecting switches are installed on the lower faces of the supporting leg boxes of the auxiliary frame respectively, vertical extract-in-place detecting switches are installed on installing plates of the vertical oil cylinders respectively, tyre off-the-ground detecting switches are installed on installing plates arranged above tyres respectively, and vertical touch-the-ground detecting switches are installed at ends of horizontal supporting legs; the eight-connected electromagnetic reversing valve, the speed control valves, the double-shaft tilt sensor and the detecting switches are connected with a PLC. Manual work control is replaced with automatic control for chassis leveling, real-time leveling for a chassis is conducted by driving leveling mechanisms such as the detecting switches, the eight-connected electromagnetic reversing valve and the PLC, the leveling efficiency is improved, and the leveling precision is improved.