883 results about "Leaf spring" patented technology

The invention relates to the technical field of intelligent unmanned ships, in particular to a wave self-adaptive unmanned ship, a self-adaptive control system and a control method.The wave self-adaptive unmanned ship comprises a main ship body, a front arch, a rear arch, a suspension system, a propelling nacelle, a rigid sliding plate and a buoy, the main ship body is connected with the rear arch and the front arch, and the rigid sliding plate is fixed to the buoy; the propulsion nacelle is installed at the tail of the rigid sliding plate, the rear arch and the rigid sliding plate are installed through two bearings perpendicular to each other, the suspension system comprises a rocker arm, a plate spring and a TPMLM actuator, the rocker arm is connected to the rigid sliding plate, the plate spring and the TPMLM actuator are connected between the rocker arm and the rigid sliding plate and support the rocker arm to be in an upward inclined posture, and the rear arch is connected to the rigid sliding plate. The front arch is connected with the rocker arm, the plate spring and the TPMLM actuator are installed in parallel in the vertical direction, the TPMLM actuator is used for outputting active control force for restraining movement of the ship body, and the unmanned ship, the self-adaptive control system and the self-adaptive control method have the advantages that wave loads can be actively counteracted, and therefore movement restraining is achieved.

The invention provides a loading safety monitoring method and system for a rear-loading vehicle and the vehicle. The method comprises the following steps that the arc height variable quantity of a plate spring of the vehicle in the current loading state is collected; based on the arc height variable quantity, a vehicle total weight estimated value is obtained through calculation; based on the axle load estimation values of the front axle and the rear axle and the axle distance of the vehicle, estimating the current gravity center height of the vehicle, and dynamically compensating the gravity center height according to the dynamic state parameters; and calculating a stability risk coefficient of the vehicle according to the total weight estimated value of the vehicle and the compensated gravity center height so as to carry out early warning. Displacement sensors are arranged on a front plate spring and a rear plate spring of a vehicle to collect arc height variation in real time, an axle load and a vehicle total weight estimated value are calculated based on a pre-calibrated plate spring rigidity coefficient, the gravity center height of the vehicle is estimated to evaluate the stability of the vehicle, and meanwhile the gravity center height is dynamically compensated based on dynamic parameters in the driving process. The evaluation precision under complex working conditions is improved, and the transportation safety is guaranteed.

The invention relates to the technical field of precise positioning control, in particular to a two-degree-of-freedom large-stroke motion platform applied to wafer detection, which comprises a base platform and a load platform surface, the top surface of the base platform is provided with a linear motion platform and a rotary motion platform which are coaxially arranged, the linear motion platform is used for driving the load platform surface to do lifting motion, and the rotary motion platform is used for driving the load platform surface to do rotating motion. The rotary motion table is used for driving the linear motion table and the load table top to do circular motion, and the linear motion table comprises a linear actuator, an air floatation guide assembly, a first feedback device and a plate spring. The integrated design is adopted, the Z shaft and the Rz shaft are coaxially arranged and share the same air floatation guide assembly, the number of parts is effectively reduced, the axial space is compressed, the structure is more compact, the size of equipment is reduced, the self weight and the assembly difficulty are reduced, non-mechanical-friction guide is achieved, and the influence of friction on precision is avoided; besides, the plate springs distributed in a single layer achieve flexible decoupling through the axial and radial rigidity difference of the plate springs, motion crosstalk is restrained, and the dynamic response speed can be increased without a complex algorithm.

A vibration motor, including a housing with a receiving space, a stator assembly fixed in the housing, a vibrator assembly received in the housing and driven by the stator assembly to vibrate, and a leaf spring connecting the housing and the vibrator assembly. The leaf spring includes an outer fixed portion fixed to the housing, an inner fixed portion fixed to the vibrator assembly, and an elastic arm connecting the outer fixed portion and the inner fixed portion. The elastic arm extends from the inner fixed portion to the outer fixed portion in a manner of rotating around the inner fixed portion. The vibration motor further includes damping glue arranged between two adjacent elastic arms for adjusting vibration damping of the vibrator assembly. The vibration motor of the present disclosure reduces material costs and improves reliability and consistency of a product.

A roller spring member for an overrunning clutch is provided. A first bridge connecting portion couples a bridge to a first spring central location of a first leaf spring. A second bridge connecting portion couples the bridge to a second spring central location of a second leaf. The roller spring member further includes at least one of, each of the first bridge connecting portion and the second bridge connecting portion including an undercut radius section, each of the first leaf spring and the second leaf spring being tapering from an associated one of the first spring central location of the first leaf spring and the second leaf spring central location of the second leaf spring to a first end and a second end, and each of the first leaf spring and the second leaf spring including a straight portion proximate the central locations.

The invention discloses a waterproof crawling robot. The robot comprises a driving mechanism, a supporting and adjusting mechanism, a camera shooting detection assembly, a slapping communication mechanism, a coupling unit and a control unit. The driving mechanism adopts four-wheel independent driving and differential steering; the supporting adjusting mechanism is of a crossed supporting rod structure. The slapping communication mechanism is composed of an eccentric cam and a firing pin or an electromagnetic releaser and a leaf spring firing pin, and mechanical pulses are transmitted to the pipe wall through an elastic cushion or a thin film resonant cavity of the coupling unit. The control unit carries out coordinated proceeding, detection and communication, a mute time slot is formed before and after slapping, acoustic signals are collected, and communication and echo ranging are achieved. According to the scheme, the strong rhythm pulse is used as a synchronous reference of communication and positioning, self-noise interference is effectively suppressed, stable communication and centimeter-level positioning are achieved in metal, full water and complex pipe networks, and the task completion rate is remarkably increased.

A retrofit kit for replacing an existing leaf spring suspension system, methods of replacing the existing leaf spring suspension systems, and suspension systems may include an upper load beam having a proximal end and a distal end, the distal end being configured to pivotally mount to a vehicle. A lower control arm includes a proximal end, a distal end, and a mounting location positioned between the proximal end distal ends. The distal end of the lower control arm is configured to pivotally engage a leaf spring mounting eye provided on the vehicle. The mounting location on the lower control arm is configured to pivotally receive the proximal end of the upper load beam.

A kind of quasi-zero stiffness vibration isolation device based on negative stiffness generated by rotatable leaf spring, quasi-zero stiffness vibration isolation device includes positive stiffness component, negative stiffness component and height adjustment pad;Positive stiffness component, negative stiffness component and height adjustment pad are all installed in outer sleeve, and the bottom surface of positive stiffness component extends from the bottom of outer sleeve, beyond the bottom surface of outer sleeve, forms height difference on level;Negative stiffness component is located above positive stiffness component, and upper end surface extends the upper end surface of outer sleeve, outer sleeve is installed in floating plate, and moves up and down with floating plate together;The negative stiffness component is the negative stiffness component formed by rotatable leaf spring combination, and negative stiffness is generated by the change of rotatable leaf spring.The rotation or movement of rotatable leaf spring negative stiffness component in the process of vibration isolation forms matching negative stiffness, so that good quasi-zero stiffness low-frequency vibration isolation performance is obtained, and the vibration isolation efficiency of floating bed system is improved;It has the characteristics of simple structure, high reliability and long service life.

The invention provides an ultra-deep well large annulus flexible righting transverse vibration reduction method, which belongs to the technical field of well drilling and drilling, and comprises the following steps of: inputting pre-drilling well drilling engineering information, and calculating a whole well section drill string vibration distribution form based on an established drill string finite element dynamic model; the tripping-in positions and the number of the flexible stabilizers and the layer number and the compression space of plate springs in the flexible stabilizers are designed, and an initial vibration reduction scheme is generated; comparing the real-time vibration data with the predicted vibration distribution pattern, carrying out real-time risk assessment, carrying out dynamic optimization on the initial vibration reduction scheme according to the real-time risk assessment, adjusting the tripping-in position and number of flexible stabilizers, the number of plate spring layers and the compression space, and generating an optimized real-time vibration reduction scheme; a flexible stabilizer is put in the designated position of the drill column; when the drill column transversely vibrates and collides with the well wall, the buffer block of the flexible stabilizer is pressed, the plate spring is driven to generate radial elastic deformation, part of radial impact kinetic energy is converted into elastic potential energy of the plate spring to be stored, and radial vibration reduction is achieved.

The invention discloses a plate spring suspension fault diagnosis method and system based on multi-sensor data and deep learning, and relates to the technical field of vehicle fault diagnosis, and the method comprises the steps: obtaining a plate spring suspension system fault diagnosis data set; based on a combined processing method of empirical mode decomposition and wavelet denoising, performing data processing on each signal data in the leaf spring suspension system fault diagnosis data set; converting two pieces of acceleration signal data and one piece of displacement signal data after data processing corresponding to each piece of fault diagnosis data into two-dimensional color image data; training a pre-constructed deep learning network model by using the plate spring suspension system fault diagnosis data set and the two-dimensional color image data; and performing plate spring suspension fault diagnosis by using the trained deep learning network model. According to the invention, real-time fault diagnosis of the plate spring suspension system can be realized, accurate identification and positioning of plate spring suspension faults can be realized, and accuracy and reliability of diagnosis results are ensured.

The utility model provides an unmanned logistics vehicle chassis and an unmanned logistics vehicle. The unmanned logistics vehicle chassis comprises a vehicle frame assembly, a front suspension assembly and a rear suspension assembly, wherein the front suspension assembly and the rear suspension assembly are arranged on the vehicle frame assembly; the upper surface of the frame assembly is used for mounting a container; the front suspension assembly comprises a transversely-arranged plate spring arranged in the width direction of the frame, the two ends of the transversely-arranged plate spring are connected with the knuckle assemblies respectively, and the middle of the transversely-arranged plate spring is connected with the frame assembly. The rear suspension assembly comprises plate spring suspension assemblies arranged left and right at intervals, each plate spring suspension assembly comprises a plate spring set formed by stacking a plurality of plate springs, the two ends of each plate spring set are connected to the frame assembly, and the middle of each plate spring set is connected to the rear axle assembly. According to the chassis of the unmanned logistics vehicle, the front suspension assembly with the transverse plate spring structure and the rear suspension assembly with the plate spring suspension assembly structure are adopted, so that the chassis is high in bearing capacity, low in manufacturing cost and good in using effect.

An airframe for a projectile having a cylinder having a bottom spring and a piston within the cylinder is provided. The cylinder has a locking assembly having a housing. A leaf spring is in the housing and coupled thereto. The housing has a limiter where the leaf spring operatively couples with the limiter and the limiter biases the leaf spring. The piston is moveable relative to the cylinder between a retracted configuration and expanded configurations. The piston has a housing where the piston moves between the retracted configuration and the expanded configurations when the piston housing receives a fluid. The piston has a groove that receives the leaf spring. The groove can align with the leaf spring in one expanded configuration where the piston groove receives the leaf spring thereby locking the piston with cylinder. In another expanded configuration, the leaf spring is outside the piston groove.

The chair according to the invention has a seat, a backrest, a support frame, and at least one S-shaped leaf spring. The S-shaped leaf spring at a first section is fastened to the support frame, the seat is mounted at a second section, and the backrest is mounted at a third section. A first curvature is provided between the first and second sections, so that in a neutral position of the chair the first section and the second section are situated essentially in parallel to one another and are spaced apart, and the third section adjoins the second section via a second, opposite curvature. A compressible spacer that is displaceably guided in the longitudinal direction of the first section is provided between the first and the second section.

An emergency trailer wheel assembly for temporarily replacing a trailer wheel includes a frame member with a mounting bracket attached on a first end of the frame member and configured for attaching to a leaf spring of a trailer and a wheel rotatably attached to a second end of the frame member.

[Problem] A design is provided that is capable of suppressing the rattling of an input element. [Solution to the problem] A leaf spring 6 has: two held sections 43, which are arranged on both sides of an input-side engagement section 14 in respect of a second direction perpendicular to a first direction, which is a direction of movement of a pressing surface 33, which moves away from or towards a pressed surface 7 and a central axis of an input element 3, and are held elastically between the input-side engagement section 14 and an input-side gripped section 34; and a base section 44, which connects the two held sections 43.

The utility model discloses a plate spring support and lower thrust rod support welding station which comprises a position changing machine assembly, a feeding table assembly and a workpiece to be machined placed on the feeding table assembly, the position changing machine assembly comprises two rotary boxes, a rectangular column is rotationally arranged between the two rotary boxes, and the rectangular column is connected with the feeding table assembly. A first baffle and a second baffle are fixedly mounted at the top and the bottom of the rectangular column correspondingly, driving motor boxes are fixedly mounted on the front side and the rear side of the first baffle correspondingly, and the driving motor boxes are fixedly connected with main driving gears through driving motors in the driving motor boxes. A head-tail frame form and a double-station five-shaft turnover positioner are adopted, manual feeding and discharging are adopted, one-key reservation automatic turnover welding is adopted, and products are assembled in the feeding process; according to the utility model, servo drive adjustment is realized, the compatibility is strong, all products can be covered, double-bit and offline programming is adopted, the production efficiency is improved, laser positioning is adopted, the welding quality is improved, the operation process is standardized, digital fool-proof is realized, and the error rate is reduced.

The utility model relates to the technical field of commercial vehicle rear axle housings, in particular to an oil-leakage-proof integral integrated rear axle housing assembly for a commercial vehicle, which comprises an axle shaft sleeve, an axle housing body and a main speed reducer mounting surface, the axle shaft sleeve is connected with the axle housing body through a fastening screw, and a main speed reducer mounting hole is arranged on the main speed reducer mounting surface. The main speed reducer mounting face is connected with the axle housing body through fixing bolts, the axle housing body is formed by integrally casting an axle housing rear cover, a plate spring seat and an ABS support fixing seat, and a main speed reducer mounting hole is a blind hole. The rear cover of the axle housing, the ABS bracket fixing seat and the plate spring seat are integrally integrated, and meanwhile, the hole of the main reducer mounting surface is made into a blind hole, so that the rigidity of the axle housing is improved, and the technical problems that the rigidity of an existing stamping and welding axle housing is poor, a traditional casting axle housing is not integrated with the rear cover, and oil leaks from the mounting hole of the main reducer surface of the stamping and traditional casting axle housing are solved.

The objective is to provide a magnetic unit that can properly hold a magnetic core. [Solution] The magnetic material unit 1 includes a magnetic material core 10 formed in an annular shape around a first direction X and divided along a second direction Y intersecting the first direction X, with the first core 11 and the second core 12 in contact along a third direction Z intersecting the first direction X and the second direction Y; a base member 20 that houses the magnetic material core 10 and has a bottom portion 21 and a side wall portion 22; a cover 30 having a support portion 31 provided opposite to the second core 12 and a cover side portion 32 provided opposite to the side wall portion 22; and a leaf spring 40 that biases the second core 12 toward the first core 11. The base side locking portion 25 provided on the side wall portion 22 and the cover side locking portion 35 provided on the cover side portion 32 are locked together by the cover 30 and the base member 20 moving relative to each other in a direction that brings them closer together.

The invention discloses a plate spring assembly and a vehicle, and the plate spring assembly comprises a plate spring support which is provided with a containing cavity; the first buffering piece is connected to the plate spring support and located in the containing cavity; the plate spring assembly comprises plate springs and noise reduction pads, the noise reduction pads are located between the two adjacent plate springs, and one ends of the plate springs and the noise reduction pads are located in the containing cavity; wherein one ends of the plate springs and the noise reduction pad are located below the first buffer piece, one end of the uppermost plate spring makes contact with the first buffer piece, and the projection, generated by the contact part of the first buffer piece and the uppermost plate spring, towards the plane where the noise reduction pad is located, at least partially coincides with the noise reduction pad. Therefore, the influence of bending moment can be avoided, and the stress concentration position can be avoided, so that the stress of each plate spring can be more uniform.

The invention relates to an axle motion instantaneous center analysis method and device, computer equipment and a medium. The axle motion instantaneous center analysis method comprises the steps that the incidence relation between the moving horizontal distance of a first center of a single plate spring in a spring assembly after longitudinal torsional deformation and the relative distance of a spring eye and the incidence relation between the effective half length and the longitudinal torsional angle of the single plate spring are obtained; differentiating the longitudinal torsion angle to obtain a proportional relation between the first vertical position and the relative distance of the spring eye; the first vertical position is the position of the first instantaneous center of the single leaf spring in the vertical direction of the first coordinate system; when the number of the plate springs is multiple, a second vertical position is obtained based on the correction coefficient of the correction proportional relation, the number of the plate springs, the effective half length of the non-main-leaf plate springs and the effective half length of the main-leaf plate springs; the second vertical position is the position of the second instantaneous center of the plurality of plate springs in the vertical direction of the second coordinate system; and based on the second vertical position and the horizontal position of the second instantaneous center, the movement instantaneous center position of the axle located at the second center of the multiple leaf springs is determined. According to the method, the accurate position of the axle movement instantaneous center can be obtained.

A stand mixer includes a securing apparatus configured to retain a bowl on a stand mixer, the securing apparatus incudes a leaf spring mounted to a bowl support at a first end portion of the leaf spring. The leaf spring extends away from the column to a second end portion of the leaf spring and defines a receiving orifice at the second end portion of the leaf spring. A retractor is configured to translate a bolt away from the second end portion of the leaf spring when a bowl support is in the nonmixing position. An extender is configured to translate the bolt toward the second end portion of the leaf spring when the bowl support is in the mixing position.

A fixed support is fixedly arranged inside a backrest, two supporting legs of a headrest rod are movably inserted into the fixed support, clamping grooves are formed in the two supporting legs in the length direction of the supporting legs, openings of the clamping grooves face backwards, a locking steel wire slides front and back and is limited in the fixed support, and the two ends of the locking steel wire are clamped into the two clamping grooves with the corresponding heights. The reset plate spring is arranged on the rear side of the middle of the locking steel wire and is integrally in an arch shape backwards, the two ends of the reset plate spring are fixed to the locking steel wire, a mounting frame is arranged at the arch crown position of the reset plate spring and fixed to the fixing support in a limited mode, and the unlocking button is arranged on the front side of the middle of the locking steel wire and installed on the fixing support. When the unlocking button is pressed backwards, the two ends of the locking steel wire can be driven to be separated from the clamping grooves, and meanwhile the reset plate spring is pressed. The headrest is simple in structure, small in installation space and convenient to operate, and unlocking of the two sides of the headrest insertion rod can be achieved through one-time pressing.

The invention relates to the technical field of metal plate stamping, in particular to a one-time punch forming device for part machining and a stamping method.The one-time punch forming device for part machining comprises a rack, a stamping table and a bending mechanism, a pressing plate is arranged on the rack, and the bending mechanism comprises a first bending plate and a sliding bearing plate; the first bending plate and the sliding bearing plate are both installed on the pressing plate in a sliding and penetrating mode, a plate spring is connected between the sliding bearing plate and the first bending plate, a pressing head is fixed to the lower end of the first bending plate, a supporting spring is arranged between the pressing head and the pressing plate in a jacking mode, the lower end of the sliding bearing plate is connected with a second bending plate in a swinging mode, and a locking mechanism is arranged between the sliding bearing plate and the pressing plate. The first bending plate moves upwards relative to the pressing plate to enable the plate spring to store energy, the plate spring drives the sliding bearing plate to drive the second bending plate to move upwards, the upper end of the second bending plate swings towards the side away from the first bending plate, and then the metal plate is bent for the second time. Energy is stored for secondary bending through downward movement of the pressing plate, and the stamping and bending efficiency is improved.

The application provides a leaf spring installation auxiliary positioning device for vehicle production, and belongs to the field of leaf spring installation equipment.The leaf spring installation auxiliary positioning device for vehicle production comprises a rack, a first positioning assembly and a second positioning assembly.The first positioning assembly comprises a first telescopic frame, a positioning sleeve and a clamping piece, and the clamping piece is arranged on the upper part of the rack.The second positioning assembly comprises a supporting frame, a bidirectional linear slide rail, a second telescopic frame, a centering piece, a lifting piece and a flattening piece.In the whole use process, the centering and fixing of the axle are realized, the clamping and positioning of the leaf spring are realized, the leaf spring is conveyed to the two sides of the axle, the relative perpendicularity between the leaf spring and the axle is ensured, the parallelism between the two leaf springs is ensured, the same side distance of the two leaf springs to the axle is ensured, the time for multiple measurement and adjustment of the installation personnel is reduced, and the installation efficiency of the leaf spring is improved.

The application provides a few-leaf spring suspension system for a sightseeing vehicle, and belongs to the technical field of vehicle suspension parts. The few-leaf spring suspension system for the sightseeing vehicle comprises a main leaf spring assembly, a secondary leaf spring assembly, a fixing assembly, an anti-loosening assembly and a damping vibration reduction assembly. The main leaf spring assembly is provided with a variable cross-section section in the middle, and the thickness of the variable cross-section section gradually decreases from the center to both ends. The length of the secondary leaf spring assembly is smaller than that of the main leaf spring assembly, and the secondary leaf spring assembly is fixedly connected with the main leaf spring assembly through a center bolt. The fixing assembly is arranged at both ends of the main leaf spring assembly, and the anti-loosening assembly is arranged in the fixing assembly. The damping vibration reduction assembly comprises a high-frequency damper, a medium-frequency damper and a low-frequency damper. The application can solve the problem of insufficient damping performance of the few-leaf spring suspension system for the sightseeing vehicle in the prior art.

The invention relates to a power connector, which comprises an insulating base, a conductive seat and a plate spring assembly, the insulating base is provided with an accommodating space, the conductive seat is arranged in the accommodating space and comprises a pair of fixing plates, a mounting space is formed between the fixing plates, the fixing plates are provided with abutting blocks protruding towards the mounting space, and the plate spring assembly comprises a connecting part, two elastic clamping parts and two buckling claw parts. The elastic clamping parts are located in the installation space and correspond to the fixing plates, inserting space is formed between the elastic clamping parts, the connecting part is connected to one sides of the elastic clamping parts, and the buckling claw parts are connected to the other sides of the elastic clamping parts and buckled with the ends of the fixing plates respectively. Each elastic clamping part is provided with a plurality of clamping plate springs, and the ends of the clamping plate springs abut against the corresponding abutting blocks. Therefore, the clamping stability of the clamping plate springs can be effectively improved, and deformation and failure caused by structural elastic fatigue of the clamping plate springs are avoided.

This invention relates to the field of trailer technology, and in particular to a semi-trailer frame and semi-trailer. The semi-trailer frame includes a leaf spring assembly, which comprises spring steel plates, pads, long rollers, and a damping adjustment assembly. Multiple leaf spring assemblies of varying lengths are included. The spring steel plates are aligned at their centers and spaced vertically, with the length of the upper spring steel plate being no less than the length of the lower spring steel plate in any two adjacent pairs. Multiple pads are also included. This invention incorporates long rollers and a damping adjustment assembly. When a lightly loaded semi-trailer encounters minor road bumps, the reciprocating rolling of the long rollers within the gaps between the spring steel plates dissipates the vibration energy. This significantly reduces the vibration force transmitted from the axle to the support frame via the leaf spring assembly, thereby filtering out minor road vibrations and improving the comfort of the driver and co-driver.

The pressing operation unit is provided with: an operation member which can be pressed by an operator; a leaf spring member that imparts an operation touch feeling by means of elastic deformation in response to a pressing operation; and a housing that holds the leaf spring member, the operating member having: an insulator that covers the housing; a first protrusion provided on one surface of the insulator; and a second protruding part which is provided on the other surface of the insulator at a position facing the first protruding part, and which is made of a material different from that of the first protruding part.

The application discloses a hollow commercial vehicle front axle and a manufacturing method thereof. The front axle is composed of an axle body and a steel plate spring seat. The axle body is a hollow structure obtained by reducing and upsetting an end portion of a seamless steel pipe, bending and pressing forming. The crossbeam and the bent neck of the axle body are thin-walled rectangular pipes with equal wall thickness and variable cross section. The fist part is a thick-walled rectangular cylinder with constant height and gradually narrowing width from the inside to the end portion. A strip-shaped hole is arranged on the outer end curved surface of the fist part and is welded and solidified by a welding plug. A concave limiting groove is arranged on the front side surface. The steel plate spring seat is composed of an upper cover and a lower support. The upper cover is clamped on the upper portion of the crossbeam, and the lower support is clamped on the middle portion of the crossbeam and covers the lower portion of the crossbeam. The hollow commercial vehicle front axle provided by the application can replace the existing forged, combined welded and punched and welded front axle, has light product weight, high bending and torsional strength, and is easy to match with the existing suspension system for vehicle mounting. The axle body has good forming quality, no defects such as folding and outer side cracks in the fist part inner cavity, and high shear performance.

Vibration and shock absorption device for equipping a multi-leaf spring, comprising: - a first buffer (1), including: a first plate (10), a first elastic coating (11), a threaded rod (12); - a second buffer (2), including: a second plate, provided with a through hole arranged to receive the threaded rod (12), a second elastic coating (21), provided with a through opening (210) arranged to face the through hole, a nut (3), arranged to cooperate with the threaded rod (12) so as to assemble the second buffer (2) to the first buffer (1) when the through hole receives the threaded rod (12), the through opening (210) being dimensioned to receive the threaded rod (12) and the nut (3). Figure 3