MXPA06006028A - Torsion bar for application in belt winders for safety belts - Google Patents

Abstract

The invention relates to a torsion bar (1), for application in belt winders for safety belts, provided on the end sections thereof with embodiments of drive and/or locking elements (2, 3), for positive connection to the corresponding devices. The torsion bar (1) and the drive and /or locking elements (2, 3) embodied on the ends thereof is produced in one piece from a non-ferrous metal, using varying extrusions in order to achieve differing torques with constant dimensions for the drive and /or locking elements (2, 3) with variable diameters for the torsion bar (1).

Description

TORSION BAR FOR APPLICATION IN CI TURON ROLLERS FOR SAFETY BELTS DESCRIPTION OF THE INVENTION The invention relates to a torsion bar for application in belt retractors for safety belts, in whose end sections drive and / or locking element configurations are provided for the positive connection with the corresponding devices. A series of variants of embodiment of torsion bars have been known, all of which are produced from steels and steel alloys by means of a cold deformation process. But by virtue of the fact that the torsion bars must be manufactured with different diameter between the driving and / or blocking elements according to the requirements of the torsional behavior, and that the degree of deformation when cold deformation only allows certain diameter ratios between the torsion bar and the driving and / or blocking elements, it was generally inevitable to also carry out a material processing with chip removal in addition to the cold deformation so that despite the invariable diameter of the driving elements and It is possible to create a substantially smaller diameter of the torsion bar itself. In addition, with conventional steel there are problems REF.:171085 of behavior at low temperatures difficult to eliminate in the material of the torsion bar, that is, the breakage of the torsion bars is much too premature. The norm of the automotive industry on behavior at low temperatures, specifically at least 5.5 revolutions at -35 ° C already exists. In this regard additional problems occur with the steel torsion bars produced by the cold deformation process. Accordingly, the invention proposed the object of creating a torsion bar for application in belt winders which is manufactured in one piece with the driving and / or blocking elements configured in their end sections, which satisfies the requirement of low behavior. temperatures and that can also be produced without further processing with chip removal. To obtain different moments of rotation with an invariable size of the driving and / or locking elements and variable diameters of the torsion bar, according to the invention this is achieved when manufacturing the torsion bar, including the driving elements and / or blocking that are configured at their ends, in one piece in a process of cold deformation of a non-ferrous metal taking advantage of the different cold extrusion. By means of these measures according to the invention it is possible to solve in a simple manner the technical problems of the extrusion by virtue of which it is possible to adapt the diameters of the impulsion and / or blocking elements and of the torsion bar using the different extrusion behavior Cold of various materials. Therefore it was again possible to achieve an adaptation in that the finished product can be manufactured without processing the material with chip removal. Additional advantages result from the fact that a substantial weight saving is possible circumstantially. In addition, no protection against corrosion is required. Depending on the non-ferrous metal used, it is possible to improve the useful life of the tools for cold deformation during the manufacture of the torsion bar. With respect to the driving and / or blocking elements, predetermined dimensions are established. An adaptation of the diameter of the torsion bar by extrusion technique was obtained with the use of a non-ferrous metal. In this aspect is not simply a change of material, but it was necessary a series of inventive steps to obtain the possibilities of cold deformation that would allow to adapt to each other diametrical relationships and even find a material capable of deformation in cold with these dimensions that also contributes the moments of rotation required in the region of the torsion bar and also in the region of the elements of impulsion and / or blocking. It is further proposed that the drive and / or locking elements configured at the ends have external dimensions of equal or greater size than those of the torsion bar itself. A very small diameter difference is also possible by the material used according to the invention., so that it is also possible to optimally use manufacturing with cold deformation. A particularly advantageous configuration exists if the torsion bar is configured with a cold deformation process of aluminum. Aluminum has a behavior of cold extrusion approximate to that of steel without preventing. But in this case, a torsional resistance behavior is obtained which, in the case of steel, only became possible with very small diameters. But then it turns out that the behavior of cold extrusion of steel is an obstacle to the use of cold deformation. And then it is necessary to carry out further processing with chip removal. Aluminum can be dispensed with in this way because it is possible to keep the diameter differences between the torsion bar and the driving and / or blocking elements small.

The optimum deformation capacity in the manufacture of a torsion bar is obtained if aluminum with a degree of purity of up to 99.5% by volume is used. The cold extrusion behavior of almost pure aluminum is just particularly suitable for the production of a torsion bar by the cold deformation process. As a result of the good deformability and the cold extrusion behavior of non-ferrous metals, and in this case in particular of aluminum or, for example, of copper, it is now also possible in a simple manner that the torsion bar be cylindrical or prismatic. By means of the possibility of optimum manufacturing with the specially adapted material it is even easier to create different construction variants of the torsion bar and also of the driving and / or blocking elements. Accordingly, it can be envisaged that the driving and / or locking elements are configured as gear wheels or as driving elements provided with crushing. However, it is also possible in this context that a transition in the form of a conical section or a groove is formed between the driving and / or blocking elements and the torsion bar. That is, by using a non-ferrous metal, and in particular a light metal such as aluminum, it is possible to obtain constructive designs with optimal torsional behavior and also with an optimum transmission of force in the driving elements and / or blocking. Other particular features and advantages in accordance with the invention are explained in greater detail by the figure with the following description: The only figure 1 is an example of a torsion bar with driving and / or locking elements configured at its ends. The torsion bar 1 shown serves for application in belt retractors for safety belts. In their end sections, drive and / or blocking elements 2 and 3 are provided, which in turn are coupled with the corresponding devices, thereby allowing, in the case of a particular effort of the safety belt, allowing a simple or multiple torsion. of the torsion bar, and thus act as a kind of shock absorber. The torsion bar 1, including the drive and / or locking elements 2 and 3 configured at its ends, is manufactured in a process of cold deformation of a piece of non-ferrous metal taking advantage of the different cold extrusion to obtain different moments of rotation with an invariable size of the drive and / or blocking elements and variable diameters of the torsion bar. The drive and / or locking elements 2 and 3 configured at the ends have external dimensions of equal or greater size than the torsion bar 1 itself. For the concept of non-ferrous metals, light metals and non-ferrous metals are essentially understood for the present invention. The non-ferrous metal sector is suitable as a material, for example, copper. In the case of light metals, aluminum is particularly favorable for producing a torsion bar in a cold deformation process. Conveniently, aluminum with a degree of purity of up to 99.5% by volume is used for this. As regards construction, substantial improvements are possible through the new materials used. For example, the torsion bar 1 can be configured cylindrical or prismatic. The driving and / or blocking elements 2 and 3 can be configured as sprockets or as drag elements provided with crushes. Between the driving and / or blocking elements 2 and 3 and the torsion bar 1, a transition 4 can be configured in the form of a conical section or a groove.

Naturally, other configurations that result from the use of non-ferrous metals and, in this case, aluminum in the production of torsion bars in a cold deformation process, are possible within the scope of the invention. By this it is possible to optimally meet the requirement of the automotive industry with respect to a behavior at low temperatures of the material of the torsion bar. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (7)

1. CLAIMS Having described the invention as above, the content of the following claims is claimed as property: 1. Torsion bar for application in belt retractors for safety belts in whose extreme sections are provided configurations of driving elements and / or blocking for the positive connection with corresponding devices, characterized in that the torsion bar, including the driving and / or locking elements configured at its ends, is manufactured in a process of cold deformation of a piece of a non-ferrous metal taking advantage of the different extrusion in cold to obtain different moments of rotation with an invariable size of the elements of impulsion and / or blocking and variable diameters of the torsion bar.
2. 2. Torsion bar according to claim 1, characterized in that the drive and / or locking elements configured at the ends have external dimensions of equal or greater size than the torsion bar itself.
3. 3. Torsion bar according to claim 1 or 2, characterized in that the torsion bar is made of aluminum in a cold deformation process.
4. 4. Torsion bar according to claim 1, characterized in that aluminum with a degree of purity of up to 99.5% by volume is used. Torsion bar according to one of claims 1 to 4, characterized in that the torsion bar is cylindrical or prismatic. Torsion bar according to one of claims 1 to 5, characterized in that the driving and / or locking elements are configured as gear wheels and / or as driving elements provided with crushes. Torsion bar according to one of claims 1 to 6, characterized in that a transition in the form of a conical section or a groove is formed between the drive and / or locking elements and the torsion bar.