TAMPER STROKE ADJUSTMENT

Abstract

The disclosure relates to a road finishing machine with a screed for producing a paving layer, wherein the screed includes at least one compacting unit for precompacting paving material supplied to the screed. The compacting unit includes at least one eccentric bushing mounted on an eccentric shaft supporting the same and rotatable to a desired angle of rotation to thereby continuously variably set a desired tamper stroke of a tamper bar of the compacting unit. For rotating the eccentric bushing, the compacting unit includes at least one adjusting mechanism, wherein the adjusting mechanism includes an adjusting drive mounted on the eccentric shaft and rotatable along with the eccentric shaft. The disclosure furthermore relates to a method for a continuously variable tamper stroke adjustment at a compacting unit of a road finishing machine.

Claims

1. A road finishing machine comprising a screed for producing a paving layer, wherein the screed includes a compacting unit for precompacting paving material supplied to the screed, wherein the compacting unit includes an eccentric bushing mounted on an eccentric shaft supporting the same and rotatable at a desired angle of rotation to thereby continuously variably set a desired tamper stroke of a tamper bar of the compacting unit, and wherein for rotating the eccentric bushing, the compacting unit includes an adjusting mechanism, wherein the adjusting mechanism includes an adjusting drive rotatable along with the eccentric shaft and mounted on the eccentric shaft.

2. The road finishing machine according to claim 1, wherein the adjusting mechanism includes an adjusting transmission mounted on the eccentric shaft and activatable by means of the adjusting drive.

3. The road finishing machine according to claim 2, wherein the adjusting drive and the adjusting transmission embody a function unit mounted on the eccentric shaft and rotatable along with rotary motion of the eccentric shaft.

4. The road finishing machine according to claim 1, wherein the adjusting mechanism is arranged within a housing surrounding the eccentric shaft.

5. The road finishing machine according to claim 4, wherein the housing is embodied as a hollow cylinder or a ring.

6. The road finishing machine according to claim 1, wherein the adjusting drive is arranged on the eccentric shaft centrically or eccentrically.

7. The road finishing machine according to claim 1, wherein the adjusting mechanism is connected to the eccentric bushing directly or by means of a positive clutch.

8. The road finishing machine according to claim 1, wherein the adjusting drive can be actuated hydraulically, electrically and/or mechanically.

9. The road finishing machine according to claim 1, wherein the compacting unit includes a plurality of independently adjustable unit sections, wherein for the respective unit sections, one adjusting mechanism each is provided.

10. The road finishing machine according to claim 1, wherein the adjusting mechanism includes at least one accumulator for an energy supply of the adjusting drive.

11. The road finishing machine according to claim 1, wherein the adjusting mechanism provides a sliding contact-induced power and/or signal transmission for the adjusting drive.

12. The road finishing machine according to claim 1, wherein the adjusting mechanism provides a contact-free power and/or signal transmission for the adjusting drive.

13. The road finishing machine according to claim 1, wherein the adjusting mechanism is connected to a controlling system for setting the desired tamper stroke.

14. The road finishing machine according to claim 1, wherein the adjusting mechanism includes at least one sensor unit for detecting the angle of rotation set between the eccentric bushing and the eccentric shaft.

15. A method for a continuously variable tamper stroke adjustment at a compacting unit of a road finishing machine, the method comprising: rotating an eccentric bushing on an eccentric shaft that supports the eccentric bushing to adjust tamper stroke, wherein for rotating the eccentric bushing, an adjusting drive mounted on the eccentric shaft and rotating along with the eccentric shaft is activated.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Below, advantageous embodiments of the disclosure will be illustrated more in detail with reference to the figures.

[0044] FIG. 1 shows a schematic side view of a road finishing machine;

[0045] FIG. 2 shows a compacting unit for a screed of the road finishing machine;

[0046] FIG. 2A shows a variant of the embodiment shown in FIG. 2; and

[0047] FIG. 2B shows a further variant of the embodiment shown in FIG. 2.

[0048] Equal components are always provided with equal reference numerals in the figures.

DETAILED DESCRIPTION

[0049] FIG. 1 shows a road finishing machine 1 with a screed 2 for producing a paving layer 3 in the paving travel direction R. The screed 2 has at least one compacting unit 4 for precompacting a paving material 5 supplied to the screed 2. The compacting unit 4 includes a tamper bar 6 which can be driven with a variable tamper stroke H and/or a variable frequency F for precompacting the paving material 5 supplied to the screed 2.

[0050] FIG. 2 shows the compacting unit 4 in an enlarged perspective representation. The compacting unit 4 has a bearing support 7 fixed to the screed body and an eccentric shaft 8 rotationally mounted thereto. The eccentric shaft 8 drives a connecting rod 9 to which the tamper bar 6 is fixed.

[0051] FIG. 2 furthermore shows an adjusting mechanism 10 which is positioned on the eccentric shaft 8 in a torque-proof manner, i.e., rotates along with it. The adjusting mechanism 10 can be activated to set a variable desired tamper stroke 11 for the tamper bar 6. By means of an activation of the adjusting mechanism 10, an eccentric bushing 12 coupled thereto and rotationally mounted on the eccentric shaft 8, and which is positioned next to the adjusting mechanism 10 on the eccentric shaft 8, can be rotated.

[0052] FIG. 2 furthermore shows that the adjusting mechanism 10 provides a housing 13 surrounding the eccentric shaft 8. The housing 13 is embodied in the form of a hollow cylinder in FIG. 2 and is positioned concentrically with respect to the eccentric shaft 8. The housing 13 is mounted on the eccentric shaft 8 in a torque-proof manner and can in particular be made of a signal- transmitting material so that components received therein can better receive and emit electric signals. The housing 13 can be embodied for receiving all function units of the adjusting mechanism 10.

[0053] FIG. 2A shows the compacting unit 4 of FIG. 2 according to a first variant in a schematic representation. For rotating the eccentric shaft 8, a drive 14, for example a hydraulic or electric motor, is provided. The adjusting mechanism 10 includes an adjusting drive 15 mounted on the eccentric shaft 8 and rotating along with a speed of the eccentric shaft 8. The adjusting drive 15 is positioned on an eccentric region 16 of the eccentric shaft 8.

[0054] Furthermore, FIG. 2A shows that the adjusting drive 15 is connected to an adjusting transmission 17. Via the adjusting transmission 17, the adjusting drive 15 is coupled to the eccentric bushing 12 which is also positioned on the eccentric region 16 of the eccentric shaft 8. By means of an activation of the adjusting drive 15, an angle of rotation φ of the eccentric bushing 12 positioned on the eccentric region 16 can be changed to set the desired tamper stroke 11 for the tamper bar 6.

[0055] In FIG. 2A, a controlling system 31 and a power source 18 are furthermore functionally connected to the eccentric shaft 8. As an alternative or in addition to the power source 18, an energy supply of the adjusting drive 15 could also be accomplished by means of an accumulator 30. The latter can be provided as a primary energy source or as an energy buffer between the power source 18 and the adjusting drive 15.

[0056] To detect the set angle of rotation φ between the eccentric bushing 12 and the eccentric shaft 8, the adjusting drive 15 includes a sensor unit 19. The controlling system 31 can be designed for signal transmission. Thus, the controlling system 31 is embodied for a signal transmission to the adjusting drive 15, and further for a signal reception of signals emitted by the adjusting drive 15, for example for receiving measuring signals of the sensor unit 19.

[0057] The power transmission and/or signal transmission can be performed by means of a power and/or signal transmission unit 20. It can be present as a sliding contact unit or alternatively be embodied in the form of an induction unit.

[0058] FIG. 2A furthermore shows that the desired tamper stroke 11 can be provided to the controlling system 31, so that an activation of the adjusting drive 15 can be correspondingly performed by means of the controlling system 31 via the signal transmission unit 20. On the basis of such an activation, a phase adjustment can be performed by means of the adjusting drive 15 which can be transmitted to the eccentric bushing 12 via the adjusting transmission 17, so that the desired angle of rotation φ to the eccentric bushing 8 results at it.

[0059] In FIG. 2A, the adjusting mechanism 10 is directly connected to the eccentric bushing 12, since both the adjusting drive 15 and the eccentric bushing 12 are positioned on the eccentric region 16 of the eccentric shaft 8.

[0060] FIG. 2B shows an alternative variant of the adjusting mechanism 10. In this variant, the adjusting drive 15 is mounted on a centrical region 21 of the eccentric shaft 8. Furthermore, the adjusting mechanism 10 provides a positive clutch 22. An activation of the adjusting drive 15 causes, via the adjusting transmission 17, the positive clutch 22, for example a claw clutch, to transmit an adjusting moment to the eccentric bushing 12 such that it is phase-shifted on the eccentric shaft 8 to set the desired tamper stroke 11.