RU2559675C1 - Car bumper and method of its strain hysteresis element fabrication - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to motor car production, particularly to devices that up the car passive safety. Beam of the vehicle structural frame is used as bumper-beam of box-like cross-section. Said bumper-beam is arranged inside case-beam also of box-like cross-section. Stack of multiplayer continuous corrugated stacks is fitted in the gap there between with interferences over crimp tops composed of steel coppered bands "crimp-in-crimp" with steel coppered bands-strips laid there between. Stacks of corrugated bands rest on smooth band-strip laid there between with tops located on each other. Beam of aluminium bent section with channel-shape cross-section. Said corrugated stacks are assembled of cold-worked, ground of unfinished, coppered bands made of spring or high-carbon steels. Bands-strips are made of cold-worked unfinished coppered bands of the same steels or structural steels. Corrugated stacks are made by the process including cutting of bands and bands-strips, cold plastic deformation and fitting of fuller board on both sides of said stacks. Said stacks are corrugated by drawing through two gears with high pitch. After coppering of corrugated bands and bands-strips stacks are assembled to fit bands-straps in there between.

EFFECT: better energy absorption.

9 cl, 9 dwg

Description

Bumper protective device for passenger cars and a method for manufacturing its elastic hysteresis element

Known bumper protective device for cars (Bumper protective device for cars. Authors Eskin I. D., Suslikov V. I., Alkeev R. I. Patent for invention of the Russian Federation RU 2012111014 A, IPC B60R 19/02. Patent holder: State educational institution of higher professional education “Samara State Aerospace University named after Academician Korolev (National Research University)” (SSAU) (RU)), which uses the front beam of the vehicle’s power frame as a bumper beam, if an ampere protective device is placed in front of the car, or its rear beam, if the bumper device is placed behind the car, both of which are made with a box-shaped cross-section with a length approximately equal to the width of the car, the bumper-beam is located inside the body, which also has a box-shaped cross-section, assembled of two beams with a channel cross-section, inserted into each other and rigidly connected with rivets or screws and nuts, and the beam of the housing, which directly interacts with as an obstacle in an emergency collision, it has ends protruding beyond the bumper beam, bent to the sides of the car, with a length of about a wheel pair and in outline repeating the contours of the car, and the distance L between each of these ends and the reciprocal part of the car with which the end contacts in lateral the impact in the bumper, measured perpendicular to the axis of the car, was selected as large as possible, but structurally acceptable, and a packet drawn from multilayer was inserted into the gap between the bumper beam and this body beam with an interference fit on the corrugation tops multi-span, corrugated bags made of steel, red-hot, polished, copper-plated ribbons “corrugations into corrugations”, between which are laid steel, red-hot, polished, copper-plated smooth ribbons - stripes with a thickness greater than that of corrugated ribbons, and packets of corrugated ribbons rely on smooth tape-strip laid between them with their vertices on top of each other, i.e. in the assembled package, the packages of corrugated tapes are connected in series and the length of the packages is selected so that at both ends of the bumper beam, body and smooth tape strips there are free sections, slightly larger displacements of the tip of the extreme corrugation of the package along the bumper beam when the corrugations are completely straightened ( deformation of the corrugations by the value of the residual deflection of the corrugations) during a frontal impact, and the parameters of the package and the tightness along the tops of the corrugations are chosen so that when creating the interference there are no plastic deformations of the corrugations Luo random displacements of the housing relative to the bumper-beam during vehicle assembly, storage and transportation.

In addition, in the case where there is no beam in the vehicle’s power frame that can be used as a bumper beam, this bumper device is made with its own bumper beam with a box-shaped cross-section, with a length approximately equal to the width of the car on which the parts are rigidly fixed, with which the bumper device is fixed on the power frame of the car.

This design of the bumper protective device by technical essence is the closest to the proposed invention and is selected as a prototype.

The disadvantages of the prototype are as follows:

The condition for choosing an interference value is incomplete, since it does not contain specific conditions, the fulfillment of which would provide effective protection for the car, driver and passengers at the speeds allowed when driving around the city (V≤60 km / h).

The manufacture of an elasto-hysteresis element (UGE) of a bumper device (a bag composed of alternating corrugated bags and smooth tape strips) from steel, red-hot, polished tapes, although it gives certain advantages - an increase in the dissipated energy by a protective device by about 10% and an extension of the range where corrugated bags are deformed elastically (see below), expensive, since it requires expensive special equipment - dies, glow containers, heating furnaces and bathtubs for stabilizing tempering, sn stresses arising in the tapes during stamping and hardening.

Therefore, the manufacture of such a UGE can be performed only in the factory.

The beam of the body, directly perceiving the impact, has a rather complex geometric shape, which makes its manufacture more expensive.

For the manufacture of UGE for the prototype, a method of plastic deformation of a corrugated bag is used, which includes cold stamping in a special stamp of all corrugated bag tapes assembled in one bag at once, or a bag of tapes of only one corrugated bag, and the bags are assembled from non-sleeved tapes made of spring or high carbon steels hardening of the stamped bag in a glow container, which can be used as a stamp in which the bag was stamped, or hardening separate from stamped corrugated bags, produced in a similar way, the implementation of stabilizing tempering, in which these stamps can be used (to maintain the shape of the corrugation).

As already indicated, the disadvantage of this method is its high cost.

This method of manufacturing the UGE of the bumper protective device by technical essence is closest to the proposed and adopted as a prototype.

Therefore, the task is to develop a highly efficient design of the bumper protective device for all types of cars, both newly developed and in operation, affordable for any car owner.

Naturally, this problem can be successfully solved if a cheaper (about a dozen times) cheaper method than manufacturing the prototype of the UGE device is proposed, since the cost of manufacturing the UGE of the prototype is the main share of the cost of the bumper device.

The problem is solved by the fact that a bumper protective device is proposed, in which the front beam of the vehicle’s power frame is used as a bumper beam, if the bumper protective device is placed in front of the car, or its rear beam, if the bumper device is placed behind the car, both of which are made with a box-shaped cross-section with a length approximately equal to the width of the car, or in the absence of beams in the power frame of the car, which can be used as a bumper beam, holding a bumper beam with a box-shaped cross-section, with a length approximately equal to the width of the car, on which the parts are fixed rigidly with which the bumper device is fixed to the vehicle’s power frame, and the bumper beam is located inside the housing, which also has a box-shaped cross section made of one or two beams with a channel cross-section, inserted into each other and rigidly connected with rivets or screws and nuts, into the gap between the bumper beam and the housing beam, which directly interacts There is an obstacle in an emergency collision, with an interference fit on the corrugation tops, a packet is inserted, made up of multilayer, multi-span, corrugated packets, assembled from steel, copper-plated corrugations into corrugations, between which steel, copper-plated smooth tape strips with a thickness greater than than the corrugated tape, and the packets of corrugated tapes rest on the smooth tape-strip laid between them with their vertices on top of each other, i.e. in the assembled package, the packages of corrugated tapes are connected in series, and the length of the packages is selected so that at both ends of the bumper beam and smooth tape strips there are free areas, slightly larger displacements of the tip of the extreme corrugation of the package along the bumper beam with full straightening of the corrugations, deformation corrugations by the value of the residual deflection of the corrugations during a frontal impact, and the parameters of the package and the tightness along the vertices of the corrugations are selected so that when creating the interference there is no plastic deformation of the corrugations, of displacements of the body relative to the bumper beam during the assembly of the vehicle, during its storage and transportation, characterized in that the body beam, which interacts directly with the obstacle in an emergency collision, is made without ends bent to the sides of the vehicle from a rectangular sheet of aluminum alloy between this beam and a package, in the case there is a beam of aluminum bent profile with a channel cross-section, in terms of repeating the contours of the car, which can be performed without bent ends or with ends protruding beyond the bumper beam, bent to the sides of the car, with a length of approximately a pair of wheels, and the distance L between each of these ends and the reciprocal part of the car, with which the end comes into contact with a side impact into it, measured perpendicular to the axis the car, it is chosen as large as possible, but structurally acceptable, corrugated bags are made of caked, brushed or unpolished, copper-plated tapes made of spring or high-carbon steels, and smooth tape strips are made of garted, polished or unpolished, copper-plated tapes of the same steel or structural steel, and the corrugated bags themselves are made below by the proposed method, and the parameters of the elastic-hysteresis element of the bumper device, the package and the tightness along the corrugation tops are selected for each passenger car model in such a way that frontal impact during crash tests according to EURO - NCAP or NCAP standards the bumper device at the first stage of impact, when the impact force increases to an amplitude value, with full straightness The corrugation of corrugated packets is dissipated only due to the work of the dry friction forces on the contact surfaces of the packets of 20 50% or more of the kinetic energy of the impact, and in case of a side impact at the bent end of the bumper device with an amplitude of the impact force 4 to 10 times less than the amplitude of the impact force crash tests for frontal impact, the bumper device at the first stage of this impact impact dissipates due to the work of dry friction forces 20-100% of the kinetic energy of this impact.

On the basis of the finite element method, we have developed a methodology for calculating the proposed bumper device and carried out its computational study for middle-class cars weighing 1300-1500 kg, which confirmed the real possibility of tuning the proposed bumper device described above. Moreover, in the calculation it was taken into account that when creating an interference fit, the deformation of the corrugated packets was elastic and the working range of elastic deformation of the packets necessary for the implementation of the described setup remained. At the same time, the condition that the preload should be such that there is no accidental displacement of the body, the beam from the bent profile and the packages relative to the bumper beam during the assembly of the car, during its storage, transportation and trouble-free operation of the car is automatically performed when the specified setting of the bumper device is created.

The specified setting of the proposed bumper protective device ensures its high efficiency, which follows from the following considerations:

this setting makes full use of the capabilities of the proposed device, although it does not exhaust them;

the car speed during crash tests for frontal impact according to the EURO-NCAP standard is 64 km / h (it is lower according to the NCAP standard), which is higher than the maximum car speed allowed in the city;

the level of passive safety of the car is estimated by the results of crash tests;

due to lack of funds, we cannot carry out crash tests of a car with the proposed bumper device and, therefore, we cannot evaluate the level of this safety in points according to the EURO-NCAP standard or in stars according to the NCAP standard;

we cannot calculate for a particular car the results of impact on it during crash tests (although we theoretically solved this problem) due to the lack of data on the stiffness characteristics of the car, which is determined during crash tests;

but we can easily determine the total kinetic energy of impact during crash tests, since the mass of the car is usually known, we can calculate the maximum energy dissipated by it due to the work of dry friction forces at the first stage of impact impact for this layout of the proposed bumper protective device and compare it with kinetic impact energy;

from simple physical considerations it is clear that the fraction of the total kinetic energy of the shock dissipated by the device in the first stage of the impact can serve as a measure of the effectiveness of the proposed bumper protective device;

a wide range of values of this measure is given because for each specific model of a car there is an optimal value for this measure, and this range can very easily be expanded towards a decrease in this measure;

the proposed bumper device, like the prototype, has a very high damping ability (several tens of times (50 ÷ 70 times) greater than that of the most recent foreign developments of bumper protective devices with elastic hysteresis elements made of polymer) and, therefore, potentially very high protective properties;

of all types of side impacts to the front or rear of the car (to the wheelset), the proposed device is configured in such a way that the oblique tangential side impacts with shock force amplitudes that are 4 ÷ 10 times less than the shock force amplitude during crash tests on frontal impact, firstly, because such impacts are most frequent during side impact on the car, and secondly, the optimal setting of the bumper device for these impacts does not spoil or almost does not spoil the optimal mood It has proposed the bumper devices for the most dangerous type of impact - frontal;

in case of a “strong” frontal or lateral impact to the bent end (“strong” impacts - frontal and lateral impacts here mean impacts with an amplitude of the impact force equal to or greater than the amplitude of the impact force with the corresponding crash tests) elastic-hysteresis element, ribbons of corrugated bags and ribbons - the strips, body, support and mounting parts of the bumper device will be plastically deformed, due to which the kinetic energy of the impact will be additionally dissipated and the proposed device may have a very effect It is normal for extinguishing “strong” frontal impacts, the amplitude of which significantly exceeds the amplitude of this force during crash tests for frontal impact;

“Small” and “medium” frontal impacts will be effectively suppressed by deformation of the corrugated packets in the elastic range.

Note that a measure of the effectiveness of shock absorption here refers to the degree of decrease in the magnitude of the amplitude of the shock force.

The geometric shape of the two hull beams and the beam located inside the hull is simple. The technology for their manufacture is especially simple, since these parts are made of standard profiles or a standard sheet, of aluminum alloy, with the simplest technological operations - cutting, flexible, drilling holes.

The manufacturing technology of the elastic hysteresis element (corrugated bags) below by the proposed method is also very simple.

Therefore, even with large series of manufacturing of the proposed bumper protective device, it can be manufactured in small factories or adjacent workshops, and the cost of manufacturing this device will be small and, when installed on a car, will slightly increase its retail price.

Note that the proposed device is a disposable device and its replacement with its small retail price after an accident will be available to any car owner.

Therefore, the proposed design solves the problem.

In the case when the front or rear beam is absent from the vehicle’s power frame or the bumper protective device is mounted outside the car, for example, to a “kenguryatnik”, the bumper protective device is made with its bumper beam with a box cross section made of aluminum alloy with a length equal to approximately the width of the car, and on it are rigidly fixed parts that secure the bumper device to the car.

In this case, the bumper beam can be made of two standard bent profiles with a channel cross-section, butt welded along the entire length of the beam, or from a standard bent profile and strip.

In addition, a bumper protective device is proposed, in which the beam located inside the device body on which the package rests is made without ends bent to the sides of the car, characterized in that the parameters of the package are selected from the condition of optimal damping of frontal impact during crash tests, and the interference fit on the corrugation tops was chosen as minimal as possible, but such that during the creation of the interference fit there were no plastic deformations of the corrugations, there was no accidental displacement of the housing relative to the bumper beam during assembly the car, during its storage, transportation and trouble-free operation of the car, and if the bumper device is located inside the car and the front or rear beam of the car’s power frame is used as a bumper beam, the bumper device is closed with a decorative bumper made in the style of the car’s design, which is fixed to the body bumper device.

In this case, the proposed bumper device does not work for side impacts. These blows are extinguished by the car itself.

The tightness on the corrugation tops of the corrugated bags is less than that of the above-described bumper device structures, therefore, with the same other parameters, the energy dissipated by the device during a frontal impact at the first stage of impact when the corrugations are completely straightened is greater than the above devices due to greater working deformation packages. Consequently, more effective damping of frontal attacks. The effectiveness of damping frontal impacts in this case also increases due to an increase in the duration of the first stage of impact, since at a given speed of crash testing, the duration of the first stage of impact is increased by a factor of approximately, the amplitude of the impact force decreases by a factor of several.

In this device, due to the absence of bent ends, the manufacturing technology of a beam located inside the housing is significantly simplified, and the weight of the device is reduced.

In order to reduce the weight of the device for cars with a small weight (up to 1000 kg), a bumper protective device is proposed, in which the device body is made of only one beam directly perceiving a frontal impact, characterized in that the ends of both shelves of the body are bent to the wall of the bumper beam .

The weight of this design is reduced, since it does not have a second beam of the hull.

In order to reduce the cost of technological equipment for the manufacture of UGE of a bumper device, a bumper protective device is proposed, characterized in that its elastic-hysteresis element (package) is composed across the width of several packages of smaller width.

In this case, the device for corrugating packages (see below) can be carried out with a manual drive, and the manufacture of this bumper device will be so simple that it can be made in a locksmith workshop at the HOA or in the garage of the car owner.

In addition, a bumper protective device is proposed, characterized in that the parameters of the corrugated bags made below by the proposed method are selected in such a way that under the influence of a frontal impact during crash tests when the bags are completely straightened, no plastic deformation occurs in their belts.

The advantage of this device is the fact that they can be used tapes of devices that have been in an accident.

For the bumper protective device of expensive passenger cars with a large mass (more than 1500 kg), the beam located inside the body, the body beams, the bumper beam and fasteners can be made of titanium alloy.

In order to significantly reduce the cost of manufacturing corrugated bags (a dozen times, or maybe even more), a method for manufacturing an elastic hysteresis element, a package of the proposed bumper device, comprising cutting ribbons to a predetermined length for the manufacture of corrugated bags and cutting smooth tape strips, stripping of barbs in places of their cutting, the manufacture of corrugated bags by cold plastic deformation of a packet of straight steel tapes, copper-plating of finished corrugated tapes and smooth floor tapes os, characterized in that for the manufacture of corrugated bags and smooth tape strips are used standard hardened polished or unpolished tapes made of spring or high carbon steel, perform: a set of packages of 4, 5 or more tapes intended for the manufacture of corrugated bags, installing on each side of these packages several layers of press puncture, corrugating these packages by rolling them through a pair of gears with a large module or a pair of meshed wheels attached to them so that the axes are parallel to the axles of the wheels, cylindrical rollers evenly spaced around the peripheral circumference of the wheels, or wheels with a smooth periodically varying contour around the circumference, then, after copper plating of the corrugated tapes and smooth tape strips, the corrugated tapes are assembled from the corrugated tapes and smooth tape strips are installed between them .

The shape of the corrugation, its initial bend are selected so that in the assembled bumper protective device with a “strong” frontal impact, at the first stage of the impact, the packets first deform in the elastic range, then elastoplastic and finally their plastic deformation until the corrugated packets are completely straightened and the shock was effectively extinguished.

The required corrugation shape and its initial bend are obtained by proper selection of a pair of interchangeable wheels, selection of the number of belts in the corrugated bag, the number of layers of presspan installed on each side of this bag, and setting the required center distance of the wheels.

We have used the FEM method to solve the problem of cyclic elastoplastic compression of a multilayer, multi-span, corrugated packet and the required shape of the corrugation and its initial deflection can be determined not only experimentally, but also by calculation.

In addition, a method for manufacturing an elastic hysteresis element, a package of the proposed bumper device, characterized in that after rolling each corrugated package of 4 to 5 tapes or each corrugated package of a bumper protective device assembled from non-copper tape, is compressed between two rigid parallel plates to the desired value of the deflection of the corrugations Y _B , carry out the complete unloading of the package from the compressive force and then copper-plated tape tapes.

When the package is compressed between two rigid parallel plates, it deforms elastoplastic.

In this way, you can correct the error in the value of the initial deflection of the corrugations, when the initial deflection turned out to be too large in the manufacture of corrugated bags by the first proposed method. The required value of the bend of the corrugation Y _B during compression of the package between rigid parallel plates can be determined not only experimentally, but also by calculation.

Performing the indicated operation of compressing the corrugated packets with their complete unloading from the compressive force provides the following loading of the corrugated packets in the assembled bumper device with a “strong” frontal impact, at the first stage of the impact, first deformation of the packets in the elastic range, then elastoplastic and, finally, them plastic deformation up to the full straightening of the corrugated bags and effective shock absorption.

As already mentioned, for the manufacture of the elastic hysteresis element of the proposed bumper protective device by these methods, expensive technological equipment is not required - a stamp, an incandescent container, an oven, a bathtub, etc., which reduces the cost of manufacturing UGE by a factor of ten and, therefore, the cost of the bumper device itself.

When using the proposed methods for manufacturing an elastic hysteresis element of a bumper protective device, there will be gaps between the tapes on the corrugated slopes of the corrugated bags in the assembled device, but this will slightly reduce the elastic-friction properties of the UGE.

research This is shown by our theoretical, calculated and experimental cyclic compression of a multilayer, multi-span, corrugated packet and is explained by the fact that both in packets without gaps between the tapes and with gaps, the compressive load between the tapes is concentrated locally at the corrugation tops and 85 ÷ 90% of the dissipated packet energy is dissipated in the contacts of the corrugation vertices with plates compressing the packet, and the rigidity of the packet without gaps, as well as the rigidity of the packet with gaps, is approximately equal to the rigidity of multi-span corrugations constant tape rigidity nC = C _{0 n,} where n - the number of ribbons in a corrugated package, C _l - separate tape rigidity in the corrugated package.

In addition, a method for manufacturing an elasto-hysteresis element of a bumper protective device is proposed, characterized in that the packet is compressed between rigid parallel plates until the corrugated packet is completely straightened.

In the case of fabrication of UGE by this method, at the first stage of a “strong” frontal impact until the corrugated UGE packets are completely straightened, they are deformed only elastically.

In order to increase labor productivity in the manufacture of UGE in the factory, a method for its manufacture is proposed, characterized in that all packages of the bumper device are assembled from corrugated non-copper tape, these packages and rigid plates are assembled in such a way that the packages are installed on plates “corrugation top to top of the corrugation ", ie in the assembled bag, the corrugated bags are connected in series and compress it so that each corrugated bag is compressed to the amount of bending Y _B or completely straightened, then the bag is completely unloaded and all corrugated bags are disassembled into separate tapes.

Assembling corrugated bags into a bag in which they are connected in series allows you to compress all packets at the same time with a force sufficient to compress one corrugated bag.

The design of the proposed bumper devices and the content of the proposed method for manufacturing an elastic hysteresis element of these devices is illustrated by figures. In the figures, a car, its power frame are shown conditionally and depicted by a thin line as a “situation” in the assembly drawing. In the figures, the initial state of the corrugated bag during compression during manufacture is shown by the main solid line, and the final one by a dash-dot line with two points. Structurally, the same parts of the proposed devices in the figures are denoted by one position.

In FIG. 1 shows a longitudinal section of the proposed bumper protective device.

In FIG. 2 shows a top view of this device.

In FIG. 3 shows a top view of a bumper protective device with a bumper beam and its mounting to the vehicle’s power frame.

In FIG. 4 shows a longitudinal section of this device.

In FIG. 5 shows a top view of a bumper device for highly efficient damping of frontal impacts. The decorative bumper and its fastening to the device case are depicted conditionally.

In FIG. 6 shows a longitudinal section of a bumper protective device with a housing made of one beam.

In FIG. 7 is a top view of this device.

In FIG. 8 schematically shows the corrugation of a pack of cured tapes by rolling between a pair of gears. In FIG. 8, the tape package is shown blackened, and the layers of press punks are shown unpainted.

In FIG. 9 schematically shows a preliminary draft of the assembled corrugated bag.

In the proposed bumper protective device (see Fig. 1), the front beam 1 of the power frame 2 of the car 3 is used as the bumper beam, if the bumper protective device is placed in front of the car, or its rear beam, if the bumper device is placed behind the car (in Fig. 1, this case is not shown), and both of these beams are made with a box-shaped cross section and with a length approximately equal to the width of the car. The bumper beam 1 is located inside the housing 4, also having a box-shaped cross section, assembled from two beams 5 and 6 with a channel cross section, inserted into each other and rigidly connected with rivets 7 or screws and nuts (not shown in Fig. 1). In the gap between the beam - bumper 1 and the beam 5 of the body with an interference fit on the corrugation tops, a packet 8 is inserted (see Figs. 1 and 2), assembled from multilayer, multi-span, corrugated packets 9, assembled from caked, sanded or unpolished, copper-plated tapes 10 made from spring or high carbon steels, “corrugation into corrugation”. Smooth tapes are laid between packets 9 - strips 11 with a thickness greater than that of corrugated tape 10, which are made of cured, brushed or unpolished, copper-plated tapes of the same steel or structural steel, and the corrugated packets 9 themselves are made by the method proposed below. Packages of corrugated tapes 9 are based on smooth tape-strip 11 laid between them with vertices on top of each other, i.e. in the assembled bag, the corrugated tape packages are connected in series. The length of the packages 9 is selected in such a way that at both ends of the bumper beam 1 and smooth tape strips 11 there are free sections 12 (see Fig. 2), slightly larger displacement of the tip of the extreme corrugation of the package 9 along the bumper beam 1 when fully straightened corrugations (deformation of corrugations by the value of the residual deflection of the corrugations) during a frontal impact. The beam 5 of the housing 4 is made of a rectangular sheet of aluminum alloy, and the beam 4 is of a standard bent profile of aluminum alloy. Between the beam 5 and the package 8 in the housing 4, there is a beam 13 of aluminum bent profile with a channel cross-section, made with ends 14 protruding beyond the bumper beam 1, bent to the sides of the car, with a length of approximately up to a pair of wheels 15. The beam 13 in terms of repeats the contours of the car, and the distance L between each of the ends 14 and the reciprocal part of the car 3, with which the end 14 is in contact with a side impact into it, measured perpendicular to the axis of the car, is selected as large as possible, but structurally acceptable. The force created by the interference between the package 8 and the beams 13 and 1, the beam 13 is pressed against the beam 5 of the housing 4, and the housing 4 by the beam 6 is pressed against the bumper beam 1.

The parameters of the elastic-hysteresis element of the bumper device (package 8) and the tightness along the corrugation tops are selected for each passenger car model in such a way that in case of frontal impact during crash tests according to EURO - NCAP or NCAP standards, the bumper device at the first stage of impact when the impact force increases to the amplitude value, with full straightening of the corrugations of the corrugated packets 9, it dissipates only due to the work of dry friction forces on the contact surfaces of the packets of 20 ÷ 50% and more of the kinetic energy of the impact I, and in case of a side impact to the bent end 14 of the bumper device with an amplitude of the impact force 4 to 10 times smaller than the amplitude of the impact force during crash tests for frontal impact, the bumper device dissipates at the first stage of this impact due to the work of dry friction forces 20 ÷ 100% kinetic energy of this impact. In addition, the parameters of the package 9 and the interference fit on the corrugation tops are selected so that when creating the interference fit, plastic deformation of the corrugations does not occur and the working range of elastic deformation of the packages necessary for the implementation of the above adjustment remains. In this case, the necessary requirement is automatically met so that accidental displacements of the beam 13, the housing 4 of the packages 9 relative to the bumper beam 1 do not occur during the assembly of the vehicle, its storage, transportation and trouble-free operation of the vehicle.

Places of free access to the package 8 can be covered with a tarpaulin cloth 16 glued to the beams 13 and 1.

In the case of installing the proposed bumper protective device on a car for which it is impossible to use the beam of the power frame as a bumper beam, or when placing it on the "kenguryatnik" (see Fig. 3 and 4), it is carried out with its beam-bumper 17 with box-shaped transverse section made of aluminum alloy with a length equal to approximately the width of the car 3, and on it are rigidly fixed (welded) parts 18, with which the bumper device is fixed to the car.

In addition, it is proposed a bumper protective device (see Fig. 5), in which the beam 19, located inside the housing 4 of the device, on which the package 8 rests, is made without ends bent to the sides of the car 3. This bumper protective device has the parameters of the package 8 are selected from the condition of optimal damping of the frontal impact during crash tests, and the interference fit on the corrugation tops was chosen as minimal as possible, but such that when creating the interference fit there would be no plastic deformation of the corrugations and no random displacements of the bumper parts of the device during the vehicle assembly during storage, transport and safe operation of the vehicle. Moreover, if the bumper device is located inside the car and the front or rear beam of the vehicle’s power frame is used as a bumper beam, the bumper device is closed with a decorative bumper 20 made in the style of the car’s design, which is fixed to the body 4 of the bumper device.

A bumper protective device is also proposed (see Figs. 6 and 7), in which the device housing 21 is made of only one beam directly perceiving a frontal impact, and the ends 22 of both shelves 23 of the housing 21 are bent to the wall 24 of the bumper beam 17.

A bumper protective device (not shown) is proposed in which its elastic-hysteresis element (packet) is composed in width of several packets of smaller width.

In addition, a bumper protective device (not shown) is proposed, in which the parameters of the corrugated bags 9 made by the method proposed below are selected in such a way that under the influence of a frontal impact during crash tests, when the bags are completely straightened, there are no plastic deformations in their belts.

For expensive business class cars, a bumper protector (not shown) of the beam located inside the housing of the housing beam, the bumper beam and fasteners can be made of titanium alloy.

A method for manufacturing an elasto-hysteresis element (packet 8, see Fig. 2) of the proposed bumper device, comprising cutting blanks 25 tapes 10 (see Fig. 2 and 8) to a predetermined length for the manufacture of corrugated packets 9 and cutting smooth tape strips 11 ( see Fig. 2), stripping the burrs of tapes in the places of their cutting, a set of packages 26 of 4, 5 or more tapes 25, installing on both sides of these packages several layers of presspan 27, corrugating these packages in the device 28 by rolling them through a pair of gears 29 with a large module or aru wheels meshing with fixed to them so that their axes parallel to the axes of the wheels, cylindrical rollers, evenly spaced around the circumference of the wheel circumference or the wheel with a smooth periodically changing in a circumferential contour (these wheels are not shown).

A method for manufacturing an elastic hysteresis element is also provided, characterized in that after the manufacture of the corrugated bags 26, each bag 26 or a packet 9 of copper-free corrugated tapes assembled from them (see FIG. 2) is compressed (see FIG. 9) between two rigid parallel plates 30 to the desired value of dish corrugations Y _B, perform a full package 26 from the unloading of the compressive force, Copper finished corrugated strip 10 (see. FIG. 2) and the smooth belt band 11 and perform the assembly of corrugated strips 10 of corrugated packages 9 and install between the smooth belts 11 bands.

For the manufacture of corrugated bags 9 and smooth stripes-strips 11 are used standard hardened polished or unpolished tapes made of spring or high carbon steel.

For the manufacture of smooth tape strips can also be used standard cured tape made of structural steel.

In addition, a method for manufacturing an elasto-hysteresis element of a bumper protective device is proposed, characterized in that the compression of the bag 26 (see FIG. 9) between the rigid parallel plates 30 is carried out until the corrugated bag 26 is completely straightened.

A manufacturing method is also proposed, characterized in that all packages 26 (see Fig. 9) or packages 9 (see Fig. 2) of the bumper device are assembled from non-copper-plated corrugated belts 10 and a packet is collected from these packages and rigid plates 30 (in FIG. (not shown) in such a way that the packages are installed on the slabs “top of the corrugation to the top of the corrugation”, i.e. in the assembled bag, the corrugated bags are connected in series and compress it so that each corrugated bag is compressed to the amount of bending Y _B or completely straightened, then the bag is completely unloaded and all corrugated bags are disassembled into separate tapes.

The assembly of the proposed bumper devices is simple and clear from their description and figures. Therefore, only the assembly of the bumper device is described (FIGS. 3 and 4).

Collect all the corrugated bags 9 from the corrugated tapes 10. Collect the bag 8 from the bags 9 and smooth tape strips 11. Install the assembled bag 8 on the bumper 17 and on the beam 8 of the beam 13. The beam 5 of the housing 4 is installed on the beam 13. The bag is compressed by 8 beams. 13 and 1 by the efforts applied to the parts of these beams protruding from the beam 5 by the amount of interference (in mm) along the tops of the corrugations of the package 8 Y _CH = n Y _H , where Y _H is the amount of interference (in mm) of one package 9. Into the beam 5 of the housing 4 insert the beam 6 and rigidly fasten these beams with rivets or screws and nuts. The assembled bumper device is released from the device in which the compressive force was created.

The proposed bumper protective device operates in a single-sided elastic hysteresis stop. The kinetic energy of the frontal impact is spent on the work of dry friction forces on the contact surfaces of the bumper protective device, on creating a reserve of potential elastic energy by the parts of the protective device and the car, and also, since the proposed device is a one-time device, on the plastic deformation of the parts of the device and the car. The bulk of the work of the dry friction forces in this case is the work of the dry friction forces when the tops of the corrugations of the packets 9 slip when they are compressed along the contact surfaces of the smooth tape strips 11, the beam 13 and the bumper 1.

Copper-bonding of corrugated tapes 10 and smooth tapes-strips 11 provides a copper-to-copper contact with a coefficient two to three times greater than that of a steel-to-steel contact, the work of dry friction forces increases approximately the same amount.

During a lateral impact at the end 14 of the device beam 13, it is displaced in a direction perpendicular to the longitudinal axis of the vehicle, due to which mutual slippage with dry friction of the device parts occurs, and a certain part of the kinetic energy of the side impact is dissipated.

The proposed bumper car protective devices have the following positive qualities:

- they are universal - they can be put on all domestic and foreign brands of cars both already in operation (in this case, standard bumpers are replaced with the proposed device or the bumper device is attached to the "kenguryatnik"), and newly created;

- they have a very high potential for dissipating properties when absorbing frontal and side impacts. With good "reference" characteristics of the car, they are able to dissipate up to 20-50% of the kinetic energy of a frontal impact and 20% of the kinetic energy of a side impact during crash tests for these impacts of a car weighing 1300-1500 kg;

- they well absorb both “small” and “medium” and “strong” frontal and “small” and “medium” tangential side impacts affecting the car in various collisions with obstacles, and the damping properties during side impacts of the proposed bumper protective devices approximately 2 times higher than that of the prototype, due to the offset with dry friction of the beam 13 relative to the beam 5 of the housing 4;

- they have dimensions and weight (without beam 1 of the vehicle’s power frame serving as a bumper of the device), approximately the same as the prototype, which can fit well into the vehicle exterior and can be structurally designed in the style of the car’s design and, therefore, do not spoil the exterior a car;

- the technology of their manufacture is very simple and does not require complex and expensive technological equipment in the case of mass production, as well as in the case of small-scale production;

- we emphasize that the technology of their manufacture is so simple that it is even possible to individually manufacture them in a "personal garage";

- the main share in the price of the proposed devices is the price of the materials that went into their manufacture, and therefore their price may be quite acceptable even for car owners with a small income and may not exceed several thousand rubles;

- they have a wide range of settings for the elastic-hysteresis characteristics of the device even without changing the technological equipment;

- they are calculated, i.e. with known "reference" characteristics of the car, you can calculate the required parameters of the device, its settings, determine by calculation the efficiency of damping both "small" and "medium" and "strong" frontal and side impacts. If the FEM model of the car is known, then it is possible to construct a picture of the deformations of the car in an accident in a 3D editor;

- they will smooth out social tension between drivers in case of a car collision even if the proposed bumper protective device is installed only on one of the colliding cars, as it, unlike individual means of protection - airbags and seat belts - will absorb shock impact on both cars involved in an accident.

The bumpers of modern cars bend and break even at a speed of 4 km / h and, although the cost of the bumper may not exceed tens of thousands of rubles, car repair will cost much more, since in a modern car a number of sensors are installed behind the bumper, which even in case of a bumper breakdown with "small" and "medium" strokes will also be broken and need to be replaced.

Among the advantages of the proposed bumper protective devices include the real possibility of ensuring one hundred percent protection of these sensors with "small" and "medium" shocks.

In conclusion, we note that, in our opinion, the widespread introduction of the proposed bumper protective devices in combination with personal protective equipment - airbags, seat belts, etc. can protect against serious injuries or even save the lives of more than one hundred, and maybe not one thousand drivers and passengers injured in an accident.

Claims (9)

1. Bumper protective device, which uses the front beam of the vehicle’s power frame as a bumper beam, if the bumper protective device is placed at the front of the car, or its rear beam, if the bumper device is placed at the rear of the vehicle, both of which are made with a box cross section with approximately equal to the width of the car, or in the absence of beams in the power frame of the car, which can be used as a bumper beam, containing its own bumper beam with a box transverse a cross-section with a length approximately equal to the width of the vehicle on which the parts are fixed rigidly with which the bumper device is fixed to the vehicle’s power frame, and the bumper beam is located inside the housing, which also has a box-shaped cross section made of one or two beams with a channel cross section inserted into each other and rigidly connected with rivets or screws and nuts in the gap between the bumper beam and the housing beam, which interacts directly with the obstacle in an emergency collision , with an interference fit on the tops of the corrugations, a packet is inserted, composed of multi-layer, multi-span, corrugated packets, assembled from steel, copper-plated corrugations into corrugations, between which are laid steel, copper-plated smooth ribbons with a thickness greater than that of the corrugated ribbons, moreover, the packages of corrugated tapes rest on the smooth tape-strip laid between them with their vertices on top of each other, in the assembled package, the packages of corrugated tapes are connected in series and the length of the packages is selected so that at both ends of the bumper beam smooth strip-strips there are free areas, slightly larger displacements of the tip of the extreme corrugation of the package along the bumper beam when the corrugations are fully straightened, deformation of the corrugations by the value of the residual deflection of the corrugations during a frontal impact, and the parameters of the package and the tightness along the corrugated vertices are chosen so that no interference of plastic corrugations occurred, there were no accidental displacements of the body relative to the bumper beam during assembly of the car, its storage and transportation, characterized in that the body beam, which directly interacts with the obstacle in an emergency collision, is made without ends bent to the sides of the car from a rectangular sheet of aluminum alloy, between this beam and the package, in the body there is a beam of aluminum bent profile with a channel cross-section, in plan repeating the contours of the car, which can be made without bent ends or with protruding ends beyond the bumper beam, bent to the sides of the car, with a length of approximately up to a pair of wheels, and the distance L between each of these at the ends and the reciprocal part of the car, with which the end contacts in lateral impact into it, measured perpendicular to the axis of the car, is selected as large as possible, but structurally acceptable, corrugated bags are made of cured, sanded or unpolished, copper-plated tapes made of spring or high carbon steel, and smooth tape-strips are made of caked, brushed or unpolished, copper-plated tapes of the same steel or structural steel, the parameters of the elastic hysteresis element b The measuring device, package and interference fit on the corrugation tops are selected for each passenger car model in such a way that in case of frontal impact during crash tests according to EURO-NCAP or NCAP standards, the bumper device in the first stage of impact, when the impact force increases to an amplitude value, the full straightening of the corrugations of the corrugated packets dissipates only due to the work of dry friction forces on the contact surfaces of the packets 20 ÷ 50% or more of the kinetic energy of the impact, and in case of a side impact to the bent end of the bumper of a device with an amplitude of impact force 4 to 10 times smaller than the amplitude of impact force during crash tests for frontal impact, the bumper device at the first stage of this impact impact dissipates 20 ÷ 100% of the kinetic energy of this impact due to the work of dry friction forces. 2. The bumper protective device according to claim 1, characterized in that when performing the beam located inside the housing on which the package rests, without ends bent to the sides of the car, the parameters of the package are selected from the condition of optimal damping of frontal impact during crash tests, and the interference fit on the corrugation tops was chosen as minimal as possible, but such that during the creation of the interference fit no plastic deformation of the corrugations occurs, there are no accidental displacements of the body relative to the bumper beam during assembly of the vehicle, its storage, conveyor irovki and trouble-free operation of the vehicle, in which case the location of the bumper device in the vehicle and used as a bumper beam-front or rear beam power vehicle frame bumper device closes decorative bumper formed in vehicle design style, which is fastened on the bumper of the device. 3. The bumper protective device according to claim 2, characterized in that when the device body is made of only one beam directly perceiving a frontal impact, the ends of both shelves of the body are bent to the wall of the bumper beam. 4. The bumper protective device according to any one of claims 1 to 3, characterized in that its elastic hysteresis element, a packet, is composed across the width of several packets of a smaller width. 5. The bumper protective device according to claim 4, characterized in that the parameters of the corrugated bags are selected so that under the influence of a frontal impact during crash tests with complete straightening of the packages there are no plastic deformations. 6. A method of manufacturing an elastic hysteresis element of a bumper protective device, comprising cutting tapes to a predetermined length for the manufacture of corrugated bags and cutting smooth tape strips, deburring tapes in the places of their cutting, manufacturing corrugated bags by cold plastic deformation of a packet of straight steel tapes, copper-plating of finished corrugated tapes and smooth tapes, characterized in that for the manufacture of corrugated bags and smooth tapes are used standard hardened sanded e or unpolished tapes made of spring or high-carbon steel, perform: a set of packages of four to five or more tapes intended for the manufacture of corrugated bags, installation on both sides of these packages on several layers of press puncture, corrugating these packages by rolling them through a pair of gear wheels with a large module or a pair of meshed wheels fixed on them so that their axes are parallel to the axles of the wheels, cylindrical rollers uniformly spaced around the peripheral circumference of the wheels, or wheels with pl the same contour periodically changing around the circumference, then after copper plating of the corrugated tapes and smooth tape strips, the corrugated bags are assembled from the corrugated tapes and smooth tape strips are installed between them. 7. A method of manufacturing an elasto-hysteresis element of a bumper protective device according to claim 6, characterized in that after rolling each corrugated bag of four to five tapes or each corrugated bag of a bumper protective device assembled from non-copper tape, is compressed between two rigid parallel plates to the required the values of the bend of the corrugations Y _B , carry out the complete unloading of the package from the compressive force and then copper tape the packages. 8. A method of manufacturing an elastic hysteresis element of the bumper protective device according to claim 7, characterized in that the package is compressed between rigid parallel plates until the corrugated package is completely straightened. 9. A method of manufacturing an elasto-hysteresis element of the bumper protective device according to claim 7, characterized in that all packages of the bumper device are assembled from corrugated tapes, a package is assembled from these packages and rigid plates in such a way that the packages are installed on the plates “top of corrugation to top of corrugation” in an assembled package corrugated packages connected in series and compress it so that each corrugated package shrank to a value Y _B of dish or completely straightened, then completely unloaded package and dismantle all corrugated s packets on separate tapes.

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