195 results about "Contact line" patented technology

A spectacle lens design includes an aperture and at least two ring-shaped focusing structures surrounding the aperture. The aperture has a dioptric power, and the ring-shaped focusing structures surrounding the aperture provide an additional power relative to the dioptric power of the aperture. A ring-shaped diffuser is arranged between neighboring ring-shaped focusing structures. Neighboring ring-shaped focusing structures can adjoin each other with a ring-shaped contact line between them forming the ring-shaped diffuser. Neighboring ring-shaped focusing structures can also be arranged at a distance to each other and at least one of the ring-shaped focusing structures provides a ring shaped focal line. Neighboring ring-shaped focusing structures can also be arranged at a distance to each other and at least one of the ring-shaped focusing structures consists of lenslets that adjoin each other so as to form a ring of lenslets and provides a plurality of foci along a ring shaped line.

The invention relates to the technical field of mechanical manufacturing and machining, in particular to a dressing wheel and honing wheel design method for improving contact line stability in the gear honing machining process. Based on workpiece gear parameters, a left and right tooth surface mathematical model is established, a honing process space coordinate conversion relation is established, a conjugate meshing relational expression is derived by combining the relative slip speed of meshing contact points and a normal vector, and a tooth surface contact line model is established; and the calculation modeling of the two-dimensional projection of the left and right tooth surface contact lines, the projection intersection point position and the variation under the same rotation angle is realized. And a honing wheel dressing contact line model under dressing wheels with different tooth numbers and a tooth surface contact line intersection projection model in the dressing and honing process under the tooth number difference are established. A honing wheel and variable tooth number dressing wheel design method is provided, and geometric and technological parameters of the honing wheel and the variable tooth number dressing wheel are determined; and a trimming and honing two-degree-of-freedom conjugate meshing relation and a modified tooth surface numerical model are constructed and verified, discretization and point cloud processing are conducted on the model, high-precision tooth surface point cloud is obtained, and accurate machining of a trimming wheel and a honing wheel is guided.

According to an aspect, there is provided a mounting assembly (20) for a hair cutting appliance (10), the mounting assembly comprising: a head (22) configured to receive a cutting unit and comprising: a body (24) extending along an elongate axis (50): a driving bridge (26) configured to couple to the cutting unit and to reciprocally move relative to the body along the elongate axis to reciprocally move the cutting unit relative to the body; a primary head bearing surface (44); and a separate secondary head bearing surface (52); a counterpart (40) pivotably coupled to the head. the counterpart comprising: a primary counterpart bearing surface (46) configured to cooperate with the primary head bearing surface to permit sliding rotation of the counterpart relative to the head about a first rotational axis (60) which is parallel to the elongate axis, and configured to contact the primary head bearing surface along a contact line to limit movement of the head towards the counterpart along a second axis (30) perpendicular to the first rotational axis; and a secondary counterpart bearing surface (54) separate from the primary counterpart bearing surface and configured to cooperate with the secondary head bearing surface to permit sliding rotation of the counterpart relative to the head about the first rotational axis, and configured to bear against the secondary head bearing surface to limit movement of the head relative to the counterpart along a third axis (70) which is perpendicular to the second axis and the first rotational axis; and a driving unit (34) comprising a driving axle (36) and a socket (38), the driving axle comprising an eccentric pin (42) cooperating with the driving bridge to impart reciprocating motion to the driving bridge, and the socket being configured to cooperate with a motor (14).

This invention provides a static parameter measurement device for overhead contact lines based on an unmanned aerial vehicle (UAV) platform, belonging to the field of railway overhead contact line inspection technology. It includes a UAV body with a laser measuring device mounted on its top and a telescopic support mounted on its side. The UAV body includes a processor chip, and the laser measuring device is connected to the processor chip. After takeoff, the telescopic support secures the UAV, and the laser measuring device measures the overhead contact line. The measured data is transmitted in real time to the processor chip for processing and analysis, ultimately achieving high-precision measurement of the static parameters of the overhead contact line. By linking the top-mounted laser measuring device with the processor chip, it is possible to conduct inspections and parameter measurements on conventional railway lines outside of designated maintenance windows, achieving high-precision, non-contact distance or terrain measurement, suitable for complex environments, and significantly improving data acquisition efficiency.

The invention provides a rigid contact line reinforcing method, which comprises the following steps of: S101, detecting a contact line on a busbar to be detected, and confirming an abrasion area of the abraded contact line on the busbar; s102, reinforcing modules are installed on the two sides of the busbar; s103, reinforcing contact lines are fixed on the two sides of the busbar in a mirror image mode through a reinforcing module, and then the reinforcing contact lines are adjusted to be parallel to the abrasion contact lines; when the train runs, the top of the carbon sliding plate slides from the unworn position on the wear contact line to the reinforcing contact line and then slides to the unworn position on the wear contact line so as to avoid the wear area of the wear contact line. The problem that manpower and material resources are seriously consumed when an abraded contact line is integrally replaced is solved, and the operation convenience and efficiency of remedying the abraded contact line are improved.

This utility model relates to an auxiliary device for manual overhead contact line laying, comprising a flatbed cart, a laying frame mounted on the flatbed cart, and a wire reel detachably mounted on the laying frame. The laying frame includes two symmetrically arranged support frames, each with a height-adjustable support plate via an adjustment mechanism. A lifting plate is mounted above the support plates via a lifting mechanism, and the outer end of the support shaft of the wire reel is mounted on the lifting plate. This auxiliary device for manual overhead contact line laying consists of a flatbed cart and two detachably mounted support frames on its top left and right sides. It has a simple structure, is convenient and flexible to use, and assists manual laying operations. In the replacement of conductors on existing overhead contact lines, workers can wait at the construction site in advance, and upon the issuance of the track maintenance window command, manually lift the reel onto the railway track for laying operations, greatly reducing machinery costs and improving construction efficiency.

The utility model provides an overhead line system composite material cantilever device insulation connector comprising a first insulation double-lug assembly, a second insulation double-lug assembly detachably connected with the first insulation double-lug assembly, and a first locking assembly for locking the first insulation double-lug assembly and the second insulation double-lug assembly. A gap for insertion of a cantilever is formed between the first insulating double-lug assembly and the second insulating double-lug assembly, the second insulating double-lug assembly is provided with a matching through groove, and the inner wall of the matching through groove is provided with a matching through hole; the second locking assembly and the third locking assembly are arranged on the cantilever connecting pin shaft. By adopting the structure, the cantilever connecting pin shaft is fixed by adopting a double-locking structure. Connection is simpler, the angle is freer, and the weight is lighter. The risk of partial discharge of the composite material cantilever device of the overhead line system can be avoided, and the power supply safety and reliability of the overhead line system of the electrified railway are improved.

The utility model discloses an auxiliary mounting device for a T-shaped positioner, which belongs to the technical field of auxiliary mounting tools for positioners and comprises a fixing box and two positioning boxes fixed on one side of the fixing box and used for mounting the T-shaped positioner. Two push rods extending into the positioning box are fixed to one side of the guide plate, a fixing column is fixed in the positioning box, two connecting blocks are movably connected to the outer portion of the fixing column, a fixing block used for clamping a contact line is fixed to one side of each connecting block, and a fixing frame is fixed to the surface of the fixing box. The surface of the fixing frame is provided with a fixing hole used for placing a wire clamp linking ring, the outer walls of the two sides of the fixing frame are both provided with through holes, and the two through holes of the fixing frame are both internally and movably connected with fixing pins used for fixing the wire clamp linking ring. The T-shaped positioner installation auxiliary device is time-saving and labor-saving in use, and can accurately complete installation work.

An overhead line system short circuit test system comprises a short circuit connecting line, an installation device and an electric control device. The two ends of the short-circuit connecting line are connected with a contact line connecting mechanism used for being connected with a contact line and a rail connecting mechanism used for being connected with a rail respectively, the contact line connecting mechanism comprises a U-shaped line clamp and an insulation pressing block used for pressing the contact line on the inner side of the line clamp, and the insulation pressing block is connected with a power cylinder used for driving the insulation pressing block to move. The rail connecting mechanism comprises a clamping jaw used for clamping a rail, and the wire clamp and the clamping jaw are electrically connected with the short-circuit connecting wire. The installation device comprises a rail car used for transporting the short-circuit connecting line, and the rail car is provided with a lifting machine used for driving the contact line connecting mechanism to move and a medium supply mechanism used for providing a power medium for the power cylinder. The electric control device is used for supplying power to the test loop and monitoring electrical parameters. In the whole installation process of the short-circuit connecting line, a worker does not need to climb a line pole and a cantilever, the installation efficiency can be greatly improved, and danger is also avoided.

The invention provides a system and method for removing an ice layer on the surface of a high-speed rail contact line based on composite laser, and relates to the technical field of laser deicing, and the system comprises an online detection unit which is used for obtaining thickness data and type information of the ice layer on the surface of the contact line in a contact line icing area when it is detected that the contact line is iced; the infrared positioning unit is used for determining three-dimensional positioning data of an icing area of the contact line and monitoring temperature information of the icing and the contact line in real time; the intelligent control unit is used for regulating and controlling working parameters of the composite laser deicing unit according to the thickness data, the type information, the positioning data and the temperature information; and the composite laser deicing unit is used for determining a laser output mode according to the working parameters so as to realize deicing operation. The problems that in a traditional high-speed rail contact line deicing mode, manual deicing is low in efficiency and high in safety risk, a contact net is prone to being damaged by mechanical deicing, electric heating deicing is high in energy consumption and poor in adaptability, and single laser deicing is insufficient in efficiency and accuracy can be solved in a targeted mode.

The invention discloses a self-adaptive pantograph-catenary intelligent control method, system and device and a storage medium, and the method comprises the steps: obtaining to-be-detected data of a pantograph-catenary system, analyzing the position and state of the pantograph-catenary system based on the to-be-detected data, judging whether the operation state of the pantograph-catenary system is abnormal or not according to an analysis result, and if the operation state of the pantograph-catenary system is abnormal, executing the step 1; if yes, self-adaptive adjustment is conducted on the pantograph-catenary system, whether foreign matter exists in the catenary or not is judged based on the pantograph image, and if yes, alarm information is sent out. An intelligent monitoring system fused by multiple sensors such as a laser radar and a high-definition camera is adopted, a multi-source heterogeneous data intelligent fusion and analysis technology is integrated, the relative position relation and state of the pantograph head carbon sliding plate and the contact line are monitored in real time, and whether response and adjustment are needed or not is analyzed and judged through an intelligent algorithm; therefore, automatic control, adjustment and alarm are realized, the pantograph and the overhead line system are ensured to be in a safe working state in a complex and changeable environment, and the current collection performance is good.

The invention provides a calculation method based on contact line profile three-dimensional splicing and profile abrasion, and belongs to the field of contact line abrasion analysis. The method comprises the following steps: acquiring left and right profile point cloud data to form a profile point cloud sequence connected along a line, and preprocessing the profile point cloud sequence; performing preliminary alignment and accurate alignment on the adjacent section point clouds to generate a continuous and consistent profile point cloud sequence, so as to obtain a complete three-dimensional profile model of the overhead line system and complete three-dimensional splicing; cutting out a profile section on the three-dimensional profile model of the contact network according to a fixed interval, and identifying an abrasion surface; fitting the profile point cloud of the wear surface, calculating wear parameters to realize wear quantitative analysis, and forming a wear change curve along the line direction; and generating three-dimensional profile and abrasion data. According to the method, the engineering application requirements of the rail transit industry on intelligent operation and maintenance, abrasion prediction and service life evaluation of the overhead line system are met, and dynamic reconstruction of the real form of the contact line and high-precision calculation of abrasion parameters are achieved.

The utility model discloses an anti-drop cantilever structure for a railway contact network, which comprises a flat cantilever, an inclined cantilever and a support arm between the flat cantilever and the inclined cantilever, and the flat cantilever and the inclined cantilever are respectively connected to an H-shaped steel column through a base. The base comprises a bottom plate connected with an H-shaped steel column, the bottom plate is connected with two vertically-installed lug plates, a flat double-lug is arranged between the two lug plates, the flat double-lug is provided with a pin shaft hole, the pin shaft hole is connected with lug holes of the two lug plates in a penetrating mode through a pin shaft, and the flat double-lug is used for being connected with a cantilever. The end, close to the bottom plate, of the flat double-lug is connected with a fixing block, the fixing block is connected with a straight rod parallel to the pin shaft, the mounting lug plates on the two sides are provided with arc-shaped grooves, and the two ends of the straight rod penetrate through the arc-shaped grooves of the two lug plates respectively. According to the cantilever structure, hole wall crack propagation and brittle fracture caused by fatigue accumulation are effectively prevented, the service life of the cantilever structure is prolonged, and the safety is improved; and the problem that the cantilever is separated from the contact line due to overlarge side-sway amplitude can be avoided, and normal operation of a railway contact network system is guaranteed.

The present application relates to the technical field of contact network polishing, in particular to a rigid contact network abnormal wear automatic polishing device, comprising displacement module one, displacement module two and two polishing modules, the displacement module one and the displacement module two are the same structure, the polishing module comprises a fixed frame and a sliding frame, the sliding frame top is provided with a polishing head and a power frame, the power frame is internally fixedly connected with a power motor, and the power motor output end is connected with a transmission shaft fixedly connected with the polishing head. In the present application, the extrusion plate is fixedly connected with the reset spring, the extrusion plate can be moved a certain distance upward by the electric telescopic rod, the extrusion plate can support the sliding frame through the reset spring, and the polishing head is abutted on the contact line, so that the polishing head can be kept close to the contact line as far as possible through the reset spring when the polishing head polishes the contact line, which is beneficial to guarantee the polishing effect of the contact line.

The present invention relates to the technical field of pinion transmission, and provides a pure rolling pinion-and-rack mechanism having parabolic function-based tooth profiles and hyperbolic tooth traces, comprising a pinion and a rack. A transverse tooth profile of each of the pinion and the rack consist of a transverse working tooth profile curve and a root transition curve, and the transverse tooth profiles of the pinion and the rack are both bilaterally symmetrical; the transverse working tooth profile curves of the pinion and the rack are parabolas; the tooth surfaces of the pinion and the rack have a hyperbolic tooth trace structure; and at least one pair of tooth meshing points of the pinion and the rack are located at nodes to achieve pure rolling meshing contact, and a meshing line formed by a movement trajectory of the meshing points of the pinion and the rack form two contact lines on the tooth surfaces of the pinion and the rack, respectively. The present invention has the advantage effects that: the contact lines are axisymmetric hyperbolas after being unfolded on a pitch cylinder surface to eliminate axial force, the theoretical value of the relative sliding speed of all meshing points on the contact lines is zero, the tooth profile tooth surface is a meshing tooth surface without relative sliding, the friction loss and noise are significantly reduced, and the transmission efficiency is greatly improved.

The application belongs to the technical field of gear design, and provides a local line contact modification method of face gear pair and electronic equipment, the method comprising: carrying out digital discrete processing on the contact surface of the face gear pair to obtain the tooth surface contact line of the face gear pair; based on a preset contact trajectory, dividing the area where the tooth surface contact line is located into a non-contact modification area and a contact modification area; superimposing the tooth surface contact line of the contact modification area with a preset segmented modification function, and superimposing the tooth surface contact line of the non-contact modification area with a preset quadratic modification function, so that the tooth surface contact line is modified towards the side away from the contact edge of the face gear pair. The technical scheme of the application can reduce the edge contact of the face gear pair while ensuring stress dispersion.

A method for operating a current collector on a roof of a rail vehicle for transferring energy thereto from a contact line of an overhead contact line, the current collector having a positioning device for moving a sliding piece relative to the contact line and pressing it against the contact line in a sliding contact position using a pressing force produced by a drive mechanism and a spring mechanism. The current collector has a measuring unit with a measuring device, at least two sensors of a sensor apparatus of the measuring device being disposed on the positioning device or the sliding piece, measured values being registered in the sliding contact position in each case by the sensors. The measured values are processed by a processing apparatus, which correlates the measured values and determines a characteristic value describing an operating state of the current collector or the overhead contact line.

The invention provides a one-step disconnecting switch for a railway contact network, and relates to the technical field of disconnecting switches, the one-step disconnecting switch comprises a mounting bracket, a movable insulator, a static insulator and a ground knife bracket, the bottom of the movable insulator is connected with an insulator mounting sleeve, and the lower end of the insulator mounting sleeve is mounted at the upper parts of a movable bearing seat and a static bearing seat; one side of the movable bearing seat is provided with a support arm, one end of the support arm far away from the insulator mounting sleeve is provided with a vertical connecting rod, the lower end of the vertical connecting rod is connected with an operating mechanism, and the operating mechanism is fixed with the mounting bracket; the operating mechanism comprises a box body, a speed reducer and a motor are installed in the box body, the output end of the motor is connected with the input end of the speed reducer, the output end of the speed reducer is provided with a rotating shaft, and the rotating shaft is provided with a rear output crank arm backwards extending out of the box body and connected with the lower end of a vertical connecting rod. According to the invention, the problem of linkage failure risk of the disconnecting switch in the prior art is solved.

This invention relates to the field of electric power steering systems, and provides a mathematical modeling method and error evaluation method for EPS worm gear tooth profiles. The mathematical modeling method includes: establishing O- xyz Coordinate system and O H - x H y H z H The invention employs a coordinate system to determine the zero-point position and scanning start point of characteristic points on the generatrix of the EPS worm gear or EPS worm wheel hob; it also determines the coordinate values ​​of the rotating moving points and the generatrix equation of the characteristic points on the generatrix of the EPS worm gear or EPS worm wheel hob; calculates the tooth profile curve points of the EPS worm gear or EPS worm wheel hob; determines the potential meshing points between the tooth profile curves of the EPS worm gear or EPS worm wheel hob and the EPS worm wheel; determines the transmission meshing contact line and contact range between the EPS worm gear or EPS worm wheel hob and the EPS worm wheel; and forms the G4 tooth profile curve of the EPS worm wheel. This invention enables simulation and error assessment of the EPS worm wheel tooth profile, providing an improved direction for corrective measures to reduce tooth profile errors.

This invention discloses a method and system for detecting excessive oil levels in a train undercarriage gearbox, relating to the field of rail transit inspection technology. The method acquires the original image of the gearbox oil level observation window using a vision camera and processes it to generate a target image; it locates the observation window area and extracts the verification mark area, fitting an initial baseline; it extracts the oil contact line and refraction feature line within the observation window, and when line segments are discontinuous, it uses interpolation or clustering algorithms to estimate and complete them; it establishes a pixel-to-physical coordinate mapping model based on the camera shooting angle, the tank setting angle, and the target line position, calculates the actual oil level height, and generates an image-level oil level line; it calibrates the baseline based on the deflection of the oil level line and the target line's centerline, and finally determines whether the oil level exceeds the limit based on the positional relationship between the calibrated baseline and the oil level line; this invention requires no modification to the original structure, achieves fully automatic and high-precision detection, has strong anti-interference capabilities, wide adaptability, and ensures train operation safety.

The invention belongs to the technical field of contact line deicing, and particularly relates to an anti-icing and ice-melting device for a contact line, which comprises a line, a shell sleeved on the surface of the line, two solar panels fixedly connected to the inner surface of the shell, an outer layer, a middle layer and an inner layer arranged on the inner surface of the shell, and a metal film fixedly connected to the inner surface of the shell. A paraffin-based PCM, an organic acid PCM and a salt hydrate PCM are arranged on the surface of the metal film sleeve circuit and the inner walls of the outer layer, the middle layer and the inner layer of the solar panel respectively, two energy storage devices are arranged on the surface of the shell, each energy storage device comprises a fixing shell arranged on the surface of the shell in a sleeving mode, a protection device is arranged on the surface of each fixing shell, and each protection device comprises a protection shell arranged on the surface of the corresponding fixing shell in a sleeving mode. Solar energy is used as a main energy source of the whole device, self-sufficiency is achieved in cooperation with the energy storage device, dependence on external power supply is reduced, the operation and maintenance cost of contact line ice melting can be remarkably reduced through long-term use, and the stability of line power supply in winter is guaranteed.

1. Name of the product in this design: Intelligent Inspection Robot for Railway Overhead Contact Line. 2. Purpose of this design: Intelligent inspection robot for railway overhead contact line inspection. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.

The invention provides a three-axis and rotating-axis high-precision delivery device for molding, which comprises a lifting subsystem, a transfer subsystem and a follow-up subsystem which are sequentially stacked from bottom to top, and the transfer subsystem is fixed on a moving seat of the lifting subsystem; the follow-up subsystem is fixed on a moving platform of the transfer subsystem, the rotary butt joint and input subsystem is fixed on a carrying platform of the follow-up subsystem, the rotary butt joint and input subsystem adopts a horizontal eccentric rotary structure, and a horizontal eccentric distance exists between the rotary center of the rotary butt joint and input subsystem and a material contact line of a conveying belt. Through geometric matching of multi-axis composite motion and butt joint, the butt joint impact and the mistaken entry risk are reduced, the beat is shortened, and the stable basket entry delivery device is suitable for stable basket entry delivery of continuous production lines such as paper pulp molding.

The utility model discloses a moisture-proof man-machine interaction device for a ship. The moisture-proof man-machine interaction device comprises a metal elastic sheet conductive film, a display screen, a panel, an integrated board and a rear cover which are sequentially arranged from top to bottom, one side edge of the lower surface of the integrated board is fixed with the tops of a group of wiring terminals, a strip-shaped hole is formed in one side edge of the rear cover, the integrated board is located in an internal cavity formed by covering the panel and the rear cover, the wiring terminals are inserted into the strip-shaped hole downwards from the upper part of the rear cover and are located outside the rear cover, and a sealing ring is arranged on the covering contact surface of the panel and the rear cover; the display screen is installed on the panel, and the metal elastic piece conducting film is arranged above the display screen and installed on the panel. According to the man-machine interaction device for the ship, only one circle of exposed contact line is formed on the maximum contact face where the panel and the rear cover are covered, two faces of the sealing ring extrude and seal the contact line, and the sealing effect of the device is effectively guaranteed due to the fact that the material elasticity of the sealing ring is matched with the size of the wall face of the outer ring of the rear cover. The moisture-proof effect on the ship is obvious.

The invention relates to an intelligent maintenance method for a simplified cantilever, maintenance operation is performed on the simplified cantilever through a robot, the maintenance operation comprises tightening operation, adjusting operation and pull-out value re-correction operation, and the robot comprises a tightening unit, at least two mechanical arm units, a carrier unit, an adjusting unit, a clamping unit and a pull-out unit. The mechanical arm units, the clamping unit and the pull-out unit are arranged on the carrier unit, and the tightening unit and the adjusting unit are arranged on the two mechanical arm units correspondingly; the tightening unit performs tightening or unscrewing operation, the adjusting unit performs calibration and reset operation, the clamping unit performs clamping and fixing operation, and the pull-out unit performs pull-out value deviation correction operation. According to the invention, manual operation is replaced, and mechanical operation of rechecking the pull-out value of the contact line of the simplified cantilever is realized.

Method for profile grinding of a periodic structure, in particular a gear tooth on a workpiece, with a dressable grinding wheel, which is designed by a dressing / profiling process for a grinding stroke to generate the final end geometry of a first side of the periodic structure, in particular the tooth flank of the gear tooth, wherein the grinding wheel is provided by the profiling / dressing process with a helical dressing track configuration having ridges and valleys, the dressing tracks of which can be assigned to a workpiece-side image of themselves determined by the grinding engagement path, wherein on the first side, in particular the tooth flank, in at least one region of its profile, locations in which the contact line of the grinding engagement is assigned to valleys of the dressing track configuration on the grinding wheel side, due to a set orientation deviation between, seen in the tangential plane at a respective location,the direction of a dressing track in a snapshot of the grinding engagement and the direction of the workpiece-side image attributable to this dressing track in which the grinding pass producing the final geometry is ground over by higher-lying, burr-proximal areas of the grinding wheel.

The invention relates to an exchange adapter system having a fixed part and an exchangeable loose part, wherein, in an operating position, the fixed part and the loose part are interlockingly joined to one another at an interface, and wherein a degree of assembly freedom oriented in a longitudinal direction of the exchange adapter system is blocked by means of locking elements which can be displaced radially in relation to the longitudinal direction. The locking elements are locking bolts which are supported in the fixed part and have a multi-axially curved actuation end and a wedge-shaped engagement end. A locking piston, which is loaded in the longitudinal direction in the direction of the interface by means of a spring and can be lifted electrically or under the control of a medium, is supported in the fixed part. In the operating position, the locking piston bears against the actuation end of each locking bolt along a contact line or along a contact surface having a contact line. In addition, in the operating position, an engagement wedge surface of the engagement end of each locking bolt bears against a truncated-cone-shaped retaining surface of the loose part. The present invention increases the operational reliability of an exchange adapter system.

The utility model discloses a passive clearance detection device for rail transit vehicles, which is characterized in that a collision displacement module is mounted on a to-be-tested vehicle, elastic displacement is generated under stress after the collision displacement module is in contact with or collides with line over-limit equipment, and an over-limit detection module is connected with the collision displacement module through a connecting rod structure. When the collision displacement module is in contact with the line over-limit equipment and an over-limit event is generated, a displacement signal is generated through the action of the connecting rod structure and is converted into an electric signal; the signal receiving and processing module receives electric signals, reads position information of a to-be-tested vehicle and records an over-limit occurrence position, the collision displacement module can adopt a threaded installation structure and a soft material, the over-limit device and the soft material are not damaged during collision of the over-limit device, the soft material is replaceable, adjustable in size and customizable, the structure is simple, and the cost is low. Miniaturized design can be adopted, the cost is low, dynamic limit detection can be carried out by a direct method, the test precision is high, repeated utilization can be realized, and an over-limit position can be quickly positioned.

The invention discloses a design method of a diamond roller for finishing a worm grinding wheel, which comprises the following steps of: firstly, finishing design of an involute gear tooth profile modification curve in a quadratic curve splicing manner, and obtaining a modification involute tooth surface equation based on an involute modification principle; then a meshing coordinate system based on a hypothetical rack method is established, a hypothetical rack tooth surface equation is obtained through meshing solving of the modification involute tooth surface equation, and furthermore, a worm grinding wheel tooth surface equation is obtained through secondary meshing solving of the hypothetical rack tooth surface equation; and finally, establishing a diamond roller trimming worm grinding wheel coordinate system, and obtaining a diamond roller profile according to the worm tooth surface equation in the step B on the basis of a contact line principle. According to the method, the problems that in the process of designing the diamond roller for the multi-section complex modified gear for the new energy automobile, the profile is prone to being concave inwards, and the precision is low are solved, accurate solving of the profile of the diamond roller is achieved, and the design and machining reliability of the diamond roller is improved.