RU70443U1 - HEEL WITH NONLINEAR SHOCK ABSORBER - Google Patents

Abstract

A shock-absorbing heel with an elastic nonlinear element is offered, which is made in the form of two springs of different stiffness connected in series: A cylinder is mounted inside the heel, with two springs of different stiffness connected in series. The heel provides a soft cushioning effect at the initial, most dangerous moment of contact of the shoe with a rigid support, when the bones of the lower leg and thighs are straightened, due to the deformation of the soft spring. In the next moment, when the bones of the lower leg and thighs form an angle substantially less than 180 ° and the muscles and screeds provide additional shock absorption, the heel softens the impact by compressing only a rigid spring. The soft upper spring during compression at the end of 1/3 of the forward push phase closes its coils and therefore, in the next phase, depreciation occurs only due to compression of the lower rigid spring. Energy dissipation occurs due to friction of the outer surfaces of the turns of the lower spring and the side walls of the upper gasket against the cylinder walls.

Description

Usage: shoe industry, namely the details of the bottom of the shoe. The inventive shock-absorbing heel includes a housing, which is made in the form of a cylinder, and an elastic element made in the form of two series-connected springs. The shock-absorbing heel has a cavity (through hole) in which a cylinder is inserted, with two springs of different stiffness connected in series, the lower turn of the lower spring abuts against the bottom of the cylinder, and the upper turn of the upper spring into a replaceable gasket made in the form of a round plate with a diameter equal to the inner diameter cylinder, in the upper part of which there is a restrictive ring. The outer surface of the turns of the lower spring and the side surface of the interchangeable gasket are in contact with the inner side surface of the cylinder to dissipate energy due to friction in the process of deformation of the lower spring and the displacement of the interchangeable gasket.

This design provides the best cushioning effect during the initial contact of the shoe with a rigid support.

Known shoes with a shock-absorbing system, containing one spring between the outer sole and the upper (application EPO No. 0215491).

The purpose of the invention: providing a better shock-absorbing effect of the heel in the initial phase of contact of the shoe with a rigid support.

Brief Description of the Drawings

Figure 1 - Scheme of interaction of the musculoskeletal system of a person with the surface of the base

Figure 2 - Phases of the initial contact of the shoe with the support (the beginning of the front push)

Figure 3 - Heel with non-linear shock absorber

Figure 4 - Connection diagram by welding wires of different thicknesses of two springs

Technical result

The decrease in the reaction force of the rigid support transmitted to the human body when walking is provided due to better depreciation of the human body in the phase of the front push, which is carried out by introducing into the shock-absorbing device two springs of different stiffness in series made of wires of different diameters, as well as by energy dissipation during friction of the outer surfaces of the coil of the spring and interchangeable gaskets on the inner walls of the cylinder.

Disclosure of invention

When walking, in the phase of primary contact of the foot with the rigid support, the bones of the lower leg and thigh are straightened, and the reaction from the rigid support is transmitted almost without depreciation to the human body, causing negative consequences. In the subsequent period of time, the bones of the thigh and lower leg form an angle (Figure 1), significantly less than 180 ° and, thereby, create a shock-absorbing mechanism that works due to the screeds and muscles. Thus, the primary contact of the heel with the support, which is about 1/3 of the front shock phase, seems dangerous. Shock absorbers used earlier - springs, elastic materials and others, as a rule, have a linear or close characteristic. Although it seems advisable to have a shock absorber with softer characteristics in the initial contact phase, and in subsequent phases, the shock absorber may have stiffer characteristics, since along with it, the muscles and ligaments of the thigh and lower leg will depreciate. Thus, the stiffness characteristic of the shock absorber must be non-linear.

With this sequence of motion, it is desirable that with the absorption of impact energy during initial contact of the heel part with the supporting surface, stability of the foot position is ensured.

Therefore, a solution is proposed when, at the initial contact of the heel with a rigid support (Figure 2), the stiffness of the heel would be less than in its subsequent rotational movement in the phase of the forward push.

The present invention describes a device mounted inside the heel, which combines the advantages of providing shock absorption and absorption of impact energy. This is achieved by installing two series-connected springs of different stiffness. The first spring has lower stiffness in order to more effectively reduce the impact force during the initial contact of the foot with a rigid support. The second spring, stiffer, provides shock absorption during subsequent contact, when the bones of the lower leg and thighs are no longer straightened, but there is still a danger of quasi-shock loading of the heel of the foot. Both springs provide cushioning and stability without eliminating the negative effects of walking. The outer surfaces of the coils of the lower spring, as well as the side surface of the interchangeable gasket, touch the walls of the cylinder, providing, due to the work of the friction forces, irreversible energy absorption. Without energy dissipation, with a quick rise of the shod leg, there will be shocks in the shock-absorbing device from the quickly straightening rigid lower spring; in the proposed design, the peaks of these shocks will be smoothed.

The shock-absorbing device (Figure 3) consists of: a spring 1 having a smaller wire diameter and lower stiffness, and a spring 2 having a larger wire diameter and stiffness than spring 1. A replaceable gasket 7 in the form of a round plate is installed on the upper part of the spring 1, which Designed for additional dissipation of shock energy and regulation of the depreciation of the device by changing its thickness. The interchangeable gasket 7 is made of sufficiently rigid material to allow the transmission of force between the heel and the springs 1 and 2 when stepping on the heel 5. The ends of the wires of the soft and stiff springs are connected end-to-end with each other, for example,

weld (Figure 4) or overlay. In the insert and main insoles, circular cutouts are made, forming disks 3 and 4, which, when advancing, move together with the heel of the foot in the direction of movement of the interchangeable gasket 7 in the cylinder placed in the cavity of the heel 5. On the inner side surface of the cylinder there is a restrictive ring 6 that holds interchangeable gasket 7 from the exit of the upper outer surface of the heel.

Principle of operation: the heel of the foot, when approaching in the phase of the front push, begins to put pressure on the disks 3 and 4 of the insoles and through the interchangeable gasket 7 on the springs 1 and 2. The upper spring 1 is designed so that when passing 1/3 of the angle α - the inclination of the lower cavity the heel to the supporting surface, the coils of the upper spring close and make the springs one rigid body. In this phase, until the coils of the upper spring are closed, both springs work together and their total stiffness is less than each of the components. When passing through the remaining 2/3 of the angle α, only the lower, stiffer spring will be compressed, but in this phase the depreciation will also occur due to the muscles and ligaments of the lower leg and thigh. At the end of the compression of the springs, when during the rolling process the pressure moves to the front of the foot, the springs 1 and 2 will begin to straighten and move up the replacement gasket 7. The upward movement of the replacement gasket 7 is completed when it reaches the limit ring 6 and the disks 3 and 4 of the insoles will occupy the original position.

The advantages of the proposed shock absorbing heel is as follows:

- providing a greater cushioning effect in the initial phase, the most dangerous for the human body contact of the foot with the supporting surface;

- energy dissipation due to friction of the outer surfaces of the turns of the lower spring and the side surfaces of the interchangeable gasket, on the machine tools of the cylinder.

A shock-absorbing heel containing a cylindrical cavity into which a cylinder with an elastic spring assembly is inserted, which enters the cavity which is closed by an upper gasket, characterized in that the spring assembly is made in the form of two springs of different stiffness in series, formed due to different diameters used for wire springs, interconnected by the ends of the turns of wires, mainly by welding, and the spring with less rigidity is located above the stiffer spring, when m in the phase of the primary contact of the heel with a rigid support, comprising 1/3 of the magnitude of the period of the front push, the amortization is carried out by both series-connected springs, and at the end of this phase, the coils of the upper less rigid spring are folded to contact each other, forming one rigid body superimposed on the coils of the lower stiffer spring that continue to work, which in the subsequent phase of the contact fulfill one shock-absorbing function, while during operation of the moving parts of the shock-absorbing device, the outer surfaces the turns of the lower spring and the lateral surface of the interchangeable gasket when sliding along the inner surface of the cylinder dissipate energy due to the work of friction forces.

Calculation of spring 1:

1. the highest voltage in the coil section at maximum load:

2. the required number of working turns of the spring:

accept 1 for design reasons

3. full spring travel to ultimate compression:

4. force compressing the spring to the contact of the turns:

5. the greatest shear stress in the cross sections of the turns:

6. the angle of elevation of the axis of the turns:

7. spring stiffness:

Calculation of spring 2

one.

2.

3.

four.

5. the greatest shear stress in the cross sections of the turns:

6.

7.

The total stiffness of the two springs:

8.

Designations

k is a coefficient taking into account the increase in shear stresses on the inner side of the turns due to their curvature;

P _con - the greatest axial load on the spring;

D is the average spring diameter ;;

d is the diameter of the cross section of the turns;

λ is the change in the working length of the spring (its draft);

δ is the step of the turns;

G is the shear modulus;

C = D / d - spring index;

i is the working number of turns;

α is the angle of elevation of the helix.

Claims (1)

A shock-absorbing heel containing a cylindrical cavity into which a cylinder with an elastic spring assembly is inserted, which enters the cavity which is closed by an upper gasket, characterized in that the spring assembly is made in the form of two springs of different stiffness in series, which are formed due to different diameters used for wire springs interconnected by ends of wire turns, mainly by welding, and the spring with less rigidity is located above the stiffer spring, when m in the phase of the primary contact of the heel with a rigid support, comprising 1/3 of the magnitude of the period of the front push, the amortization is carried out by both series-connected springs, and at the end of this phase the coils of the upper less rigid spring are folded to contact each other, forming one rigid body superimposed on the coils of the lower stiffer spring that continue to work, which in the subsequent phase of the contact perform one shock-absorbing function, while during operation of the moving parts of the shock-absorbing device, the outer surfaces the turns of the lower spring and the side surface of the interchangeable gasket when sliding along the inner surface of the cylinder, dissipate energy due to the work of friction forces.