JPH041374Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The invention is a driving propulsion shaft for automobile wheels, and has a double conical tube extending between joints. It relates to a type in which the diameter lies in the longitudinal center of the double conical tube.

In the automobile industry, it is necessary to transmit the drive power from the drive (engine and transmission) to the driven wheels of the motor vehicle in a noise-proof manner, with structural costs that are economical even in mass production, and which are especially required for this purpose. Maintaining a predetermined maximum weight of the swivel shaft is a problem for the engineer. Hollow shafts (hence also called tubes) made from fibers, for example carbon fibers, are currently used as a solution.

BACKGROUND OF THE INVENTION A swivel shaft of this type, known from DE 31 39 247 B60K17/22, is intended to eliminate Cardan joints. In this case, however, this swivel shaft is to be coupled in a driveable manner between an internal combustion engine located at the front of the motor vehicle and a transmission located in the region of the rear wheels to be driven. It must be installed where the relative movement of the component units is relatively small. A tube wound from this fiber is generally cylindrical, ie, has a constant internal diameter, and its joint ends are reinforced by an additional layer.

The swivel shaft described in DE 28 21 677 B60K17/22 is also intended to be installed as a support tube between the engine and the transmission of a motor vehicle. The swivel shaft, which is also made of fiber-reinforced plastic and is therefore also referred to as a tube, has a conically enlarged tube part which is provided as a connection to the transmission. The central region of this tube is also of conical design. This construction advantageously saves weight and provides the excellent vibration and damping properties of the fiber-reinforced plastic tube. The conical tube end is reinforced with a woven fabric layer embedded in a synthetic resin base.

German Patent Application No. 3240762 B60K17/22 discloses a method with a double conical tube between the synchronizing joint and/or the movable joint.
A swivel shaft of the type mentioned at the outset, ie a drive propulsion shaft for motor vehicles, is described. According to the material designation given in this specification it is a metal tube. According to the double-conical shape of this tube, its largest diameter section is located at the longitudinal center of the double-conical tube, and its smallest diameter section is at the end, ie at the joining point with the joint. This double conical tube is designed to reduce weight without sacrificing bending strength.

[Problems to be Solved by the Invention] The problem to be solved by the invention is that the driving propulsion shaft for automobiles having a double conical tube of the type mentioned at the beginning requires additional costs in the component parts and their manufacture. The aim is to improve the sound insulation, in particular of the sound transmitted to the object, while maintaining satisfactory properties, in particular the low weight and high load capacity associated with the shape.

[Means for Solving the Problems] According to the present invention which solves this problem, (a) the double conical tube is made of a fiber-reinforced plastic material, and (b) the double conical tubes are mutually compatible within the range of their maximum diameter. (c) both tube sections are connected to each other in a torque-transmitting manner only via at least one connection made of a rubber-like material; , d. The connecting portion is disposed between molded portions parallel to the axis of the joint pipe that partially overlap each other,
Each coupling tube is non-rotatably coupled to opposite ends of the tube section.

[Effect] In the present invention, not only a material known per se, for example a textile material, is used for the swivel shaft (driving propulsion shaft for automobiles), but also a double conical tube with two oppositely directed It is divided into conical tube sections, each conical tube section being connected by a sound-insulating connecting component. joint,
That is, based on the fact that a swivel joint, a fixed joint and a movable joint are used, the flexible shaft according to the invention can be attached to the end of a double conical tube to the part to be connected, i.e. for example the transmission of a motor vehicle and the driven wheels. It can also be provided in cases where there is a relatively large relative movement between the two. Due to the large change in the elastic modulus of the double conical tube according to the invention due to the change in its constituent materials, the transmission of sound transmitted to the object via the free shaft is significantly reduced. This is because the construction material of the double conical tube starts from one joint made of metal and then changes from metal to fibre-reinforced plastic and then from fibre-reinforced plastic in the center of the double conical tube. from the rubber-like elastic material to the fiber-reinforced plastic, and then from the fiber-reinforced plastic at the other end of the double conical tube. This is because the material has changed to metal (the other joint).
Where the material changes, that is, where the material transitions,
Since it is an acoustic reflection point, if the double conical tube is divided into two parts as in the present invention, more material transition points can be obtained, and thus more acoustic reflection points, that is, a multiple reflection mechanism can be obtained. As a result, the vibration energy which would cause bending vibrations of the drive shaft is already kept low. Moreover, since the driving propulsion shaft according to the present invention has the shape of a conical tube, it does not have a natural frequency, so bending vibrations can be avoided. This is because the natural frequency is determined by the material, length, wall thickness, and diameter of the pipe, but if the pipe is conical, the diameter of the pipe varies infinitely in the axial direction, so the natural frequency This is because it will change infinitely.

According to the embodiments of the present invention described in the utility model registration claims 2, 3, and 4, the double conical tube is given locally different material properties, so that Further reflection points are provided.

[Example] As shown in FIG.
The swivel shaft, i.e. the driving propulsion shaft, with its metallic connection between the movable joint 2 and the movable joint 2 has a double conical tube, designated as a whole by 3, which in its central region has a , that is, it is divided by a joint 4 into two tube sections 5 and 6 tapered in opposite directions at the point of greatest diameter. Both tube sections 5 and 6 are made of a fiber-reinforced plastic material, for example glass fibers and/or carbon fibers and/or aramid fibers (as will be explained later with reference to FIG. 4). Aramidfaser).

This joint 4 consists of joint pipes 7, 8 made of metal, which partially surround each other, and a rubber-like material with a soundproofing effect, which is bonded to both joint pipes 7, 8 by vulcanization. It consists of a connecting part 9 consisting of.

This construction of the swivel shaft provides excellent strength with minimal weight and also provides excellent sound insulation of the sound transmitted through the object. This is because there are many sound reflection points in the sound transmission path from the drive device to the upper structure of the vehicle to which this flexible shaft is installed.
This is because the manufacturing technology used in manufacturing the free shaft avoids discontinuous natural frequencies.

The manufacture of this joint 4 is also simple in terms of manufacturing technology, as is clear from FIG. In the embodiment shown, both coupling tubes 7 and 8 (only coupling tube 7 is shown in FIG. 3) are manufactured from hollow blanks of circular cross section, each of which has a tube section 5.
and 6 are manufactured with a circular contour area 7a and a corrugated area 7b for coupling in a torque-transmitting manner. This corrugated area 7b serves for meshing engagement with a corresponding area formed in the other coupling tube (in the illustrated example, the coupling tube 8) and arranged concentrically with respect to this corrugated area 7b. . This corresponding range is particularly indicated by reference numeral 8b in Figure 2.
It is shown by. Direct metal contact between the two coupling tubes 7 and 8 is avoided by means of the coupling part 9 made of a rubber-like material.

FIG. 4 shows a side view of one tube section 5, the other tube section 6 being constructed mirror-symmetrically with respect to the plane of the joint 4. In order to obtain additional acoustic reflection points, the fiber layers may be wrapped differently in the forward direction (i.e. from left to right as seen in Figure 4) and in the return direction (i.e. from right to left as seen in Figure 4). It is wound with angles α and β. Also,
Different materials, for example glass fibers, carbon fibers and aramid fiber-plastic materials, may be superimposed as individual layers.

To further increase the acoustic reflection, a fabric strip 10 is locally coated, which fabric strip 10 is permanently bonded to the fiber layer by means of plastic.

Naturally, depending on the individual use case,
These various means for obtaining "discontinuity" in the transmission path of sound transmitted to an object may be used individually or in any combination.

[Brief explanation of drawings]

Figure 1 is a longitudinal sectional view of the drive shaft according to the present invention.
Fig. 2 is a cross-sectional view taken along the - line in Fig. 1, Fig. 3 is a perspective view of one component of a joint tube with a tapered shape in opposite directions, and Fig. 4 is a cross-sectional view of one of the components of a double conical tube. It is a side view of a part. 1...Fixed joint, 2...Movable joint, 3...Double conical tube, 4...Joint, 5, 6
... Pipe portion, 7, 8 ... Joint pipe, 7a ... Circular contour range, 7b ... Waveform range, 8b ... Corresponding range, 9 ... Connection portion, 10 ... Woven fabric strip.

Claims (1)

[Claims for Utility Model Registration] 1. A drive propulsion shaft for an automobile, which has a double conical tube extending between joints, and the maximum diameter of the double conical tube is equal to or greater than the length of the double conical tube. In the central type, a) the double conical tube 3 is made of a fiber-reinforced plastic material, and b) the double conical tube 3 is tapered in opposite directions one after the other in the area of its maximum diameter. It is divided into two tube sections 5, 6, c. Both tube sections 5, 6 are connected to each other in a torque-transmitting manner only via at least one connection 9 made of a rubber-like material, (d) The connecting portion 9 is disposed between the axially parallel molded portions of the joint tubes 7 and 8 that partially overlap each other, and each of the joint tubes 7 and 8 is arranged between the mutually facing portions of the tube portions 5 and 6. A driving propulsion shaft for an automobile, characterized in that the end portion is unrotatably connected. 2. The utility model according to claim 1, wherein the tube portions 5 and 6 are formed at different angles α and β when viewed in the reciprocating direction and/or are wound from different fiber materials. Drive propulsion shaft for automobiles. 3. The driving propulsion shaft for an automobile according to claim 1 or 2, wherein the double conical tube 3 is wound symmetrically around the connecting portion 9. 4 Local reinforcing member 10 on the double conical tube 3
A drive propulsion shaft for a motor vehicle according to any one of claims 1 to 3 of the claims registered as a utility model, wherein the drive shaft is provided with: