RU1835469C - Spring having device for changing its length - Google Patents

Abstract

Usage: in car suspensions to change the stiffness of the springs. The inventive spring with a device for changing its length contains lodgements made of two threaded parts interconnected by a spring element having a cylindrical section with an average diameter equal to the outer diameter of the thread and with a step t equal to the pitch of the lodgement, defined depending on the dimension t CCU a / 2 where R is the radius of the PR ° B0 locks of the spring element, a is the angle of the thread profile, turning sequentially into a conical and cylindrical section, the latter has a tight winding of turns, the average diameter of which ryh equal to: DCp Di + 2R, where DI is the outer diameter of the threaded protrusions of the lodgements, and the spring is equipped with a nut installed in the second cylindrical section. In addition, lodges with a spring element are arranged evenly in a spiral spring. 1 s.p. f-ly, 3 ill.

Description

The invention relates to devices for varying the length and stiffness of a spring.

Fig. 1 shows a diagram of a device for changing the length of a spring; Fig. 2 shows a mechanism of a device for changing a spring length; Fig. 3 shows a calculation diagram for a thread pitch t of a threaded section of a tool tray.

Spring 1 contains lodgements 2 and 3 mounted on its coils 4 and 5. Each of lodgements 2 and 3 is made with threaded parts 6 and 7, the axis of which coincides with the axis of the coils of the spring element 8 having a cylindrical thread section .9 with an average diameter DCp equal to the outer diameter of the threaded parts 6 and 7, and the pitch t is equal to the thread pitch of the parts 6 and 7 and is determined according to the following geometry of FIG.

t - "cos" 72

where a is the angle of the thread profile of parts 6 and 7, deg,

R is the radius of the wire of the spring element 8.

Section 9 of the spring element 8, go over the conical section 10 of the tension-compression spring with the possibility of folding the turns of this section inward to each other under compression, and the section 10 of the spring element 8 passes into the cylindrical section 11 with tightly wound coils, the average diameter of which is DCp Di + 2R, where Di is the outer diameter of the threaded protrusions of the lodgements. The threaded portion 9 of the spring element 8 is provided on the outside with parallel flanges 12 for mounting an open-end wrench. On the part of section 11, on section 7 of lodgement 3, nut 13 is installed.

Device for changing the length of the spring (tool tray 2, 3, spring element

00

with

01 N O O

8) can be arranged evenly in a spiral spring 1 to ensure uniform stiffness of all turns. The lodgements 2, 3 are connected to the spring 1 by means of friction pads 14.

A spring with devices for changing its length works as follows. Spring load 1 d. Using the key associated with the flanges 12, the profile spring element 8 (nut 13 in the lower position) is screwed onto the threaded protrusion 6, then part 11 of the spring element 8 is pressed from below, with the nut 13 (which may not be), the presence of nut 13 allows provide pre-compression of the spring element 8 and, under certain conditions, even extend the coils 4, 5 of the spring 1 in the loaded position. Thereafter, a load is applied, for example, the mass of the car chassis, and the length of the spring 1 is checked in a compressed state. If necessary, the spring 1 is unloaded, manipulations with the spring element 8, nut 13 give the load back, achieving the desired length of the spring 1 under load. In the process, additional forces can act on the spring 1, while the spring coils that are not connected to each other through devices for changing the length will come closer to each other, and the coils 4, 5 connected to each other through the spring elements 8 have increased stiffness and bearing capacity.

If the devices for changing the length of the spring are arranged evenly in a spiral, the stiffness of all the coils increases uniformly, and each coil has equal stiffness and deformation. This reduces the stroke of the spring 1, but the stiffness and bearing capacity can be significantly higher than when fully compressed until the coils of the spring 1 touch without devices for changing its length due to the presence of additional profile spring elements and redistribution of the load on the coils of the spring elements and

elimination of the full convergence of the spring coils.

In this way, the characteristic of spring 1 with devices for

changing its length according to any law by adjusting the profile spring elements 8, their various designs (wire diameter, pitch angle, cone, winding diameter), their different location between different turns of spring 1. At the same time, spring 1 is protected from subsidence and its increase service life since overload is avoided.

FORMULA AND SECTION

Claims (2)

1. A spring with a device for changing its length, containing lodges mounted on its coils, characterized in that, in order to adjust stiffness and bearing capacity, each of the lodgements is made of two threaded parts, the axis of which coincides with the axis of the coils, interconnected by a spring element having a cylindrical section with an average diameter equal to the outer diameter D of the thread, and with a spiral pitch t equal to the pitch t lodgement threads. 2 R defined by the dependence of t -tn-. cos si1 where R is the radius of the wire of the spring element, and is the angle of the thread profile, turning sequentially into conical and cylindrical sections, the latter has a tight winding of coils, 5 average diameter which is equal Dcp Di + 2R, where DI is the outer diameter of the threaded protrusions of the lodgements, and the spring is equipped with a nut mounted on the second cylindrical section. 2. The spring according to claim 1, about t and h and ya and with that. which, in order to ensure equal load-bearing capacity of the turns, the lodgements with the spring element are evenly spaced along its spiral. FIG. 1