GB2342634A

GB2342634A - Ship drive with auxiliary engine

Info

Publication number: GB2342634A
Application number: GB9918666A
Authority: GB
Inventors: Wilhelm Schaefer
Original assignee: A Friedrich Flender AG
Current assignee: A Friedrich Flender AG
Priority date: 1998-10-16
Filing date: 1999-08-06
Publication date: 2000-04-19
Anticipated expiration: 2019-08-06
Also published as: KR20000028712A; GB2342634B; GB9918666D0; JP2000142580A

Abstract

A ship drive comprises a main engine, a propeller shaft directly driven by the main drive in normal operation by way of intermediate and thrust shafts, and an auxiliary drive with an electric motor for driving the intermediate shaft in emergency operation. The drive also includes an auxiliary thrust bearing which is connected to the thrust shaft and an output shaft of the main drive in normal operation and which is releasably connected to the intermediate shaft by way of a rotationally stiff, but axially flexible diaphragm coupling. For emergency operation, the diaphragm coupling is released by removal of self-centring cone pins (53) from aligned bores of flanges (51, 52) of the coupling. Removal is effected by an axially displaceable guide flange (60) with retaining pins (63) secured to the cone pins (53). The retaining pins (63) are resiliently mounted in the guide flange (60) so that the cone pins (53), when removed from the flanges (51, 52), are radially and axially movable to facilitate alignment with and entry into the bores.

Description

SHIP DRIVE The present invention relates to a ship drive.

In DE 196 23 914 A1 there is disclosed a ship drive consisting of a drive engine and propeller shaft, which is directly connected therewith and provided with a propeller and the thrust of which is taken up by a thrust bearing. For auxiliary and emergency operation, the known ship drive has a supplementary drive consisting of an electric engine which is operable selectably as a generator or a motor and which is connected with a transmission by way of a clutch. A gearwheel of the transmission surrounds the propeller shaft, which is connected with the gearwheel by way of a flexible coupling. Arranged between the transmission and the drive engine and on a separate section of a propeller intermediate shaft is a play-free switchable coupling, which is combined with a play-free auxiliary thrust bearing transmitting the propeller thrust. In the case of auxiliary or emergency operation of the ship, this auxiliary thrust bearing is activated, whereby the correspondingly reduced propeller thrust can be introduced by way of the auxiliary thrust bearing to a thrust bearing arranged in the drive engine and thus into the ship hull.

In the case of a ship drive described in DE P 197 29 046.9, a significant constructional simplification is achieved by replacement of an expensive switchable clutch by a rotationally stiff, but axially flexible diaphragm coupling. The diaphragm coupling can be clamped by a first element thereof between a flange of the propeller intermediate shaft and a further, opposite flange of the thrust shaft. A second element of the diaphragm coupling can be fastened to the auxiliary thrust bearing. The two elements of the diaphragm coupling can be held together by way of threaded taper pins which are distributed at the circumference and which are supported in a support ring. In normal operation, the pressure blocks of the auxiliary thrust bearing can be tightened against the flange of the drive side and the first-mentioned flange of the thrust shaft, so that the full propeller thrust is able to be transmitted by way of this bearing statically into the thrust bearing of the drive engine and can thus be introduced into the ship hull. The diaphragm coupling takes over the torque transmission. The tightening of the pressure blocks is preferably effected by a threaded ring, which at the rear side of the first-mentioned flange of the thrust shaft is arranged thereon and supported against the inwardly disposed surface of a support collar formed in bell shape. The support collar in turn can be fixedly connected with the flange at the drive side and joumailed on the thrust shaft. In order to be able to actuate the threaded ring, cutouts, which extend through the wall, can be provided in the circumferential region of the support collar.

For auxiliary and emergency operation of the ship the pins can be withdrawn from the diaphragm coupling, so that a direct connection between the intermediate shaft and thrust shaft and thus the drive side no longer exists. According to whether, in the case of emergency operation, forward travel or reverse travel is to be provided, the corresponding pressure block of the auxiliary thrust bearing comes into contact. This contact enables transmission of the reduced propeller thrust to the thrust bearing arranged in the drive engine. Depending on the respective level of power to be transmitted in the emergency operation, a pressure oil lubrication is required, or a filling up of the bearing may be sufficient. In the former case the appropriate components have channels so that the supplie oil can pass into the region of the pressure blocks and conduct away friction heat.

In the case of lower power the heat radiation extends over the casing. So that the threaded ring cannot unintentionally rotate in the switched-in or switched-out setting of the auxiliary thrust bearing, the ring is preferably secured by appropriate means, for example pins or wire snaps. The switched-out setting signifies a previous rotation of the threaded ring so that the clamping is cancelled and the pressure blocks have the required play.

A specific disadvantage with this ship drive is that a comparatively long time is needed for a switching-in and switching-out of the coupling, which is no longer acceptable to costconscious shipping companies.

There is therefore a need for a ship drive which enables the coupling of an engine to an auxiliary thrust bearing to be produced and cancelled relatively quickly, so that the economic viewpoints with respect to uncoupling of the engine from the propeller drive are taken into consideration.

According to the present invention there is provided a ship drive consisting of a drive engine and a propeller shaft, which is directly connected therewith and provided with a propeller and the thrust of which is taken up by a thrust bearing, as well as an auxiliary drive comprising an electric engine which is to operate selectably as a generator or a motor and which is connected with a transmission by way of a clutch and a gearwheel of the transmission surrounds the propeller intermediate shaft and is connected therewith by way of a flexible coupling, wherein a play-free, releasable and mechanically positive connection is arranged between the transmission and the drive engine, which has a flange at the drive side, on a thrust shaft and is combined with an auxiliary thrust bearing, which has forward and reverse pressure blocks and which is activatable in the case of auxiliary or emergency operation of the ship, wherein the correspondingly reduced propeller thrust is introduced by way of the auxiliary thrust bearing to a thrust bearing, which is arranged in the drive engine, into the ship hull, and wherein a rotationally stiff, but axially pliant diaphragm coupling connected with the propeller shaft and the auxiliary thrust bearing forms the play-free, mechanically positive connection and in normal operation the auxiliary thrust bearing is clamped by means of the pressure blocks against the flanges of the drive side and the thrust shaft, characterised in that a guide device is mounted for the release of cone pins arranged in holes in flanges of the diaphragm and that the pins, after release of nuts, are journalled to be radially and axially movable in the guide device.

A significant constructional advantage of a ship drive embodying the invention is that for the switchable diaphragm coupling there is provided a releasable connection which enables quick switching-in and switching out of the coupling. For that purpose, the releasable connection, which comprises pins arranged in flange holes of the coupling, is equipped with guide means for release of the pins, which, after release of the nuts, are radially and axially movable in the guide means.

For preference, the guide means comprises a guide flange, a switching fork, a guide bearing, abutment or retaining pins, O rings and plate springs, wherein the abutment pins are mounted at the cone pins and are in tum mounted by way of the O rings in the flange holes of the flange. In one embodiment the abutment pins are screwed into the pins and in another embodiment the abutment pins are welded in the pins. Moreover, the guide flange can be arranged on the guide bearing to be axially movable and can be engaged with the switching fork. It is advantageous if the conicity of the pins lies beyond the selflocking limit and it is also advantageous if the guide means is in non-interchangeable engagement with characterising holes of the flanges. In addition, it is of advantage if, on switching-out of the coupling, the diaphragm packet does not have to be released, but remains firmly screw-connected, so that it does not come apart. The releasable connection is particularly suitable for quick switching-in and switching-out of the coupling and is therefore advantageous in terms of time and thus in terms of cost. A ship drive embodying the invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a schematic half longitudinal section of part of a ship drive illustrating the general layout ; and Fig. 2 is a view of the detail Z, to enlarged scale, of Fig. 1, but in modified form for a ship drive embodying the invention.

Referring now to the drawings, there is shown part of a ship drive which comprises a drive engine (not illustrated in Fig. 1), usually a slow-running Diesel engine, connected by way of a flange 1 at the drive output side and by a diaphragm coupling 4 with a propeller intermediate shaft 22. The connection of the intermediate shaft 22 with the actual propeller shaft, inclusive of propeller attached thereto, is not illustrated here. The drive is a direct drive, in which the setting of the desired propeller rotational speed is effected by way of regulation of the rotational speed of the drive engine. The arrangement of a transmission between drive engine and propeller is not required in this case. So that the ship remains manoeuvrable even in the event of breakdown of the drive engine, an auxiliary drive is provided. This comprises an electric engine 40, which is operable selectably as a motor or a generator and which is connected with a transmission 32 by way of a clutch 33. In this embodiment the transmission 32 has the form of a two-stage input transmission, with its main gearwheel 31 fastened to a hollow shaft 30, which engages around the intermediate shaft 22. The connection of the transmission 32 with the intermediate shaft 22 is effected by way of a highly elastic coupling 20, which is connected with the intermediate shaft 22 by means of an annular divided flange 21 and a flange 23 of the intermediate shaft 22.

The transmission of the propeller thrust to a thrust bearing (not illustrated) arranged in the drive engine is effected by way of forward pressure blocks 8 and reverse pressure blocks 7. The forward pressure blocks 8 are fastened to an end face, which is opposite the flange 1 at the drive side, of a flange 13 of a thrust shaft 2. The reverse pressure blocks 7 are fastened to an end face, which faces the flange 13 of the thrust shaft 2, of a flange 15 of a receiving collar 5. The receiving collar 5 is arranged to be axially displaceable on a slide bearing 16 mounted on the thrust shaft 2. The collar 5 is provided on a cylindrical body part thereof with a threaded portion 17. A threaded ring 6 is rotatably arranged on the threaded portion. The ring 6 is supported by an end face, which faces the drive side, against the inner surface of a support collar 3 formed in bell shape. The support collar 3 is fixedly connected with the flange 1 at the drive side by screws 18. Axial displacement of the collar 5 is effected by way of an adjusting spring 12, which is placed in a recess of the body part of the receiving collar 5 and engages in an axially extending groove of the support collar 3. The support collar 3 is joumalled on the thrust shaft 2 by way of the body part of the receiving collar 5 and by way of the slide bearing 16. As shown in Fig. 2 the support collar 3 consists of two ring halves, which are connected together by way of a parting joint screw connection 19. Lubrication of the pressure blocks 7 and 8 is effected by way of interconnected channels 11 which are provided in the support collar 3, the receiving collar 5 and the thrust shaft 2 and which open into intermediate spaces in which the pressure blocks are arranged.

In normal operation of the ship, the pressure blocks 7 and 8 are clamped against the flanges 1 and 13 by the threaded ring 6, so that the propeller thrust is introduced by way of this connection into the thrust bearing arranged in the drive engine. The diaphragm coupling 4, which is rotationally stiff, but axially yielding, takes over the torque transmission. In this embodiment the diaphragm coupling 4 consists of a highly elastic disc 25, which is clamped between the flange 23 of the intermediate shaft 22 and a flange 26 of the thrust shaft 2. The disc 25 is covered on the side remote from the main drive by a support ring 27 and on the other side by a flange 28 constructed in cover shape. The connection between the support ring 27, disc 25 and flange 28 is effected by way of threaded cone pins 14, which are secured by nuts 29. The required connection of the diaphragm coupling 4 with the auxiliary thrust bearing takes place by way of screws 34, which connect the flange 28 of the diaphragm coupling 4 with the support collar 3.

In the case of emergency operation of the ship, the auxiliary drive is activated and the electric motor 40 drives the transmission 32 by way of the switched-in clutch 33 and thus the intermediate shaft 22 by way of the resilient coupling 20. As the auxiliary drive has a substantially lower power than the drive engine, the propeller thrust is correspondingly reduced. Nevertheless, however, this must be absorbed. To achieve this, access is gained to the ring 6 by way of an opening 9, which is formed in the circumferential region of the support collar 3, so that the clamping action can be released through rotation of the ring 6. A protective cover 10 over the opening 9 has to be removed beforehand. In addition, after loosening of the nuts 29, the cone pins 14 of the diaphragm coupling have to be drawn, so that no torque can be transmitted between the intermediate shaft 22 and the support collar 3. After elimination of the clamping actions, the pressure blocks 7 and 8 have play. In the case of forward travel in emergency operation, the forward pressure blocks 8 come into contact with the stationary flange 1 at the drive side and statically transmit the reduced propeller thrust. The thus arising friction heat must be conducted way. According to the level of power to be transmitted, a filling up of the auxiliary thrust bearing may be sufficient, or pressure lubrication may be required by way of the alreadymentioned channels 11. In the case of reverse travel in emergency operation, the flange 13 of the thrust shaft 2 comes into contact with the reverse pressure blocks 7 and the reduced propeller thrust is conducted by way of the stationary receiving collar 5, threaded ring 6, support collar 3 and the flange 1 connected therewith on the drive side into the thrust bearing arranged in the drive engine.

The detail Z of the diaphragm coupling in Fig. 1 is illustrated in enlarged scale in Fig. 2 in the form present in a ship drive embodying the invention. In the illustrated form, a flange 51 corresponding to the flange 28 is connected to a flange 52 of the diaphragm coupling by way of cone pins 53 (only one shown) each with a locknut 54. A diaphragm packet 55 of the coupling is firmly connected with the flange 52 and a support ring 57 by way of nut and-bolt connections 56 (only one shown). The diaphragm packet 55 is connected with a shaft 58 by way of inner nut-and-bolt connections 59 (only one shown).

The torque from the flanges 51 and 52 is transmitted to the diaphragm packet 55 by way of the connections 56 and ring 57 and onto the shaft 58 by way of the connections 59. A predetermined number of cone pins 53 located in holes in the flanges 51 and 52 ensures transmission of torque at the relevant level.

For quick switching-in and switching-out of the coupling it is necessary for the cone pins 53, which correspond with the pins 14 in Fig. 1, to be removed. For that purpose there is provided a guide device consisting of a guide flange 60, a switching fork 61, a guide bearing 62, abutment pins 63, O rings 64 and plate springs 65. By means of the guide device, the cone pins 53 are drawn back after release of the lock nuts 54, the pins being radially and axially guided relative to the guide flange 60. The guide flange 60, which stands in engagement with the switching fork 61, is axially moved on the guide bearing 62 by way of the fork. The cone pins 53 are guided by way of the abutment pins 63, which are screwed into or welded to the cone pins 53. The pins 63 are in tum mounted in holes in the guide flange 60 by way of the O ring 64. The O rings 64 provide a radially pliant guidance and thus permit exact alignment of the cone pins 53. The plate springs 65, after release of the lock nuts 54, assist the release of the cone pins 53 from the holes in the flanges 51 and 52.

Claims

CLAIMS 1. A ship drive comprising a drive engine, a propeller shaft provided with a propeller and directly drivable by the drive engine in normal operation by way of an intermediate shaft and a thrust shaft, a thrust bearing arranged in the drive engine to absorb the thrust of the propeller shaft, an electric engine selectably operable as a generator or a motor to provide auxiliary drive for auxiliary or emergency operation, transmission means connected with the electric engine by way of a clutch and comprising a gearwheel which surrounds the intermediate shaft and is connected therewith by way of a flexible coupling, an auxiliary thrust bearing activatable in auxiliary or emergency operation to transmit reduced thrust of the propeller shaft to the thrust bearing in the drive engine and comprising forward and reverse pressure blocks which in normal operation are clamped against flanges of the thrust shaft and the drive engine, and a diaphragm coupling which is rotationally stiff but axially yielding and which is connected with the thrust and intermediate shafts and detachably connectible with the auxiliary thrust bearing so as to provide a releasable, substantially play-free and mechanically-positive coupling between the transmission means and the drive engine, wherein the detachable connection of the diaphragm coupling is provided by cone pins engaged in bores in flanges of the coupling and removable therefrom by guide means, the cone pins when removed being retained by the guide means to be radially and axially movable relative thereto.
2. A ship drive as claimed in claim 1, the guide means comprising a guide flange displaceable relative to the flanges of the coupling by displacing means, and retaining pins retaining the cone pins and resiliently mounted in bores in the guide flange.
3. A ship drive as claimed in claim 1, wherein the retaining pins are resiliently mounted in the bores in the guide flange by plate springs and O rings.
4. A ship drive as claimed in claim 2 or claim 3, wherein the retaining pins are threadedly connected to the cone pins.
5. A ship drive as claimed in claim 2 or claim 3, wherein the retaining pins are welded to the cone pins.
6. A ship drive as claimed in any one of claims 2 to 5, wherein the guide flange is arranged on a guide bearing to be movable in the axial direction of the shafts and the displacing means comprises a fork engaging the guide flange.
7. A ship drive as claimed in any one of the preceding claims, wherein the cone angle of the cone pins is greater than the self-locking limit.
8. A ship drive as claimed in any one of the preceding claims, wherein the guide means has a unique rotational orientation relative to the flanges of the diaphragm coupling.
9. A ship drive as claimed in any one of the preceding claims, wherein the diaphragm coupling comprises a diaphragm fixedly connected to one of the flanges of the coupling by way of threaded connecting means and a support ring and remaining connected to that flange when the coupling is detached.
10. A ship drive substantially hereinbefore described with reference to Fig. 1, as modified by Fig. 2, of the accompanying drawings.