PRODUCTION ASSEMBLY AND METHOD FOR HYBRID COMPOSITE DRIVESHAFT TUBE

Abstract

The present invention relates to a drives haft comprising an elongated monolithic composite tube (20) with a front joint (10) having a tube yoke (12) and a rear joint (40) at a distance from the front joint (10) both are provided at corresponding opposite ends thereof characterized in that an inner layer (24) is comprising carbon or glass fibers which are coaxially wound on top of each other and an outer layer (22) wound directly on the inner layer (24) and the ratio (h1/h2) between the thickness of carbon fiber winding (hi) and glass fiber winding (h2) is bigger than 0.1.

Claims

1. A driveshaft comprising an elongated monolithic composite tube with a front joint having a tube yoke and a rear joint at a distance from the front joint both are provided at corresponding opposite ends thereof characterized in that an inner layer is comprising carbon or glass fibers which are coaxially wound on top of each other and an outer layer wound directly on the inner layer and the ratio (h1/h2) between the thickness of carbon fiber winding (h1) and glass fiber winding (h2) is bigger than 0.1.

2. The driveshaft according to claim 1, wherein the outer layer of the composite tube is substantially composed of carbon fiber.

3. The driveshaft according to claim 2, wherein the inner layer of the composite tube is substantially composed of glass fiber.

4. The driveshaft according to claim 1, wherein the ratio (h1/h2) between the thickness of carbon fiber winding (h1) and the thickness of glass fiber winding (h2) is between 0.8-1.2.

5. The driveshaft according to claim 1, wherein the outer periphery of the composite tube is fully composed of the outer facing side of the outer layer.

6. The driveshaft according to claim 1, wherein the outer layer forming the outer periphery of the composite tube is composed of carbon or glass fiber.

7. The driveshaft according to claim 1, wherein the glass fiber is composed of zebra winding in the outer layer.

8. The driveshaft according to claim 1, wherein the outer layer of the cardan shaft tube is the composite tube selected from the group of carbon, glass or epoxy as a hybrid material.

9. The driveshaft according to claim 8, wherein the amount of carbon used in the outer layer differs the weight between 0.1% and 10%, especially around 5%.

10. A production method to manufacture a driveshaft according to claim 1 comprising the steps of providing an hollow cylindrical inner layer by fiber winding process reaching predetermined glass fiber winding thickness (h2) by merely winding glass fiber; reaching predetermined carbon fiber winding thickness (h1) with filament twisting process to the outer side of the inner layer until a composite tube is provided by fully twisting carbon fiber; securing a front joint and a rear joint along a connection part to corresponding ends respectively edges of the composite tube, is respectively.

11. The production method to manufacture a driveshaft according to claim 10, the inner layer winding number and the outer layer winding number is arranged such that the glass fiber winding thickness (h2) and carbon fiber winding thickness (h1) is substantially equal to each other.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0015] FIG. 1 is a front view of a representative embodiment of the composite driveshaft of the present invention.

[0016] FIG. 2a is a cross-sectional illustration of the composite driveshaft shown in FIG. 1.

[0017] FIG. 2b is a cross-sectional illustration of a composite driveshaft with increased carbon layer thickness.

DETAILED DESCRIPTION OF THE INVENTION

[0018] In this detailed description, the intentive subject matter has been described with reference for examples, such that there is no restriction and only to better describe the subject matter.

[0019] In FIG. 1, a driveshaft comprising a one-piece composite tube (20) is shown from the front. A tube yoke (12) is secured coaxially to the inner cavity of the composite tube (20) from one end by a known securing method, for example welding, shape bonding, etc. From the other end, a rear joint (40) is secured by a welding seam (32) circumferentially arranged on a connection part (30). A universal joint (14) on the tube toke (12) enables a flange yoke (16) to be attached to the composite tube (20) from the front joint (10).

[0020] In FIG. 2a, the composite tube (20) used in a driveshaft is shown in cross-section. Inner layer (24) is obtained in a hollow cylindrical form by winding the glass fiber onto a mandrel (not shown) at a 45° angle (eg 100 rpm). The outer layer (22) is obtained by winding the carbon fiber onto the inner layer (24), again at a speed of winding the inner layer (24), at an angle of 45°. Carried out experiments showed that a composite tube (20) where the ratio of glass fiber winding thickness (h1) to carbon fiber winding thickness (h2) and glass fiber and carbon fibers having different characteristic mechanical properties have an effective resistance against fatigue compared to other composite tubes. In FIG. 2b, winding thicknesses are designed differently. The ratio (h1/h2) of the carbon fiber winding thickness (h1) to the glass fiber thickness (h2) is selected as 0.1. In this case, too, the laminate thickness ratio provided an application in which the driveshaft twisting strength is sufficient compared to a two-part steel driveshaft and the natural bending frequency remains small.

[0021] In composite structures, including driveshaft tubes, the mechanical properties are mainly determined by the mechanical properties of the fibers and the orientation of the fibers within the tube. The fibers providing the best in strength, stiffness and cost have been selected in the driveshaft composite tube (20). The fiber orientation can be varied and calculated to provide the desired torque force and axial stiffness.

TABLE-US-00001 REFERENCE NUMBERS 10 Front joint 12 Tube yoke 14 Universal joint 16 Flange yoke 20 Composite tube 22 Outer layer 24 Inner layer 30 Connection part 32 Weld 40 Rear joint