A BOGIE-GRIPPING TRANSFER DEVICE

Abstract: The object of the invention is a transfer device (2) for gripping bogie wheels (6), which is intended to move an aircraft (1) or other wheeled device on a base, which transfer device (2) includes a frame section (8, 18) and supported on this friction rollers (14, 15) that grip the bogie wheel (6) and motors (13) to rotate them, at least three friction rollers for each one, and pressure devices (20, 23) to press the friction rollers (14, 15) against the wheel (6), and which transfer device (2) includes a power device and transmission devices to provide the motors (13) with power, and devices to place the friction rollers (14) around the wheels and to remove them. The intention of the invention is to create a wheel-gripping transfer device. In accordance with the invention the placing devices of the friction rollers (14) of the second wheels of the in-line wheels (6) on both sides are attached to horizontal slides placed on one or more frame beams (8), so that the friction rollers (14, 15) are able to settle in a position corresponding to the distance between the axles of the set of bogie wheels (3).

Description: A Bogie-gripping Transfer Device The object of the invention is a transfer device that grips bogies, which is intended to move an aircraft or other device equipped with bogie wheels over a base, which transfer device includes a frame component and supported on this friction rollers that grip four or two in-line bogie wheels and rotate them, and motors to drive the rollers, at least three rollers per wheel, and pressure devices to press the friction rollers against the wheels, and which transfer device includes a power source and transmission equipment to feed the driving power to the motors and devices to place the friction rollers around the wheels and to remove them from the wheels. The construction of a transfer device can be substantially lightened if the rotational force is transferred to the air¬ craft's own wheel from a drive wheel or friction roller belon¬ ging to the transfer device. A construction for a completely general purpose transfer device is shown is Finnish Patent Application FI 833275 (partly corresponding to 085/ 01265) . This requires no contact with the bogie of the aircraft to press the drive wheel against the aircraft wheel. The pressure is created by means of the mutual movement of pressure rollers placed around the wheel of the aircraft and connected by an intermediate member. In its most general form the intermediate member draws the two pressure rollers connected by it towards one another, when they are pressed against the wheel between them. At least one of the pressing wheels is now a friction roller or drive wheel, which transmits rotational force to the wheel of the aircraft. Other transfer devices belonging to the field of the invention are shown in Finnish Patent Applications FI861714, FI870313, and FI870710 and in USA Patent US 3,005,510. In practice nearly all aircraft are equipped with either double wheels or still larger bogie wheels. A transfer device that grips bogie wheels is shown in the aforementioned PCT publication O85/01265. This is shown in Figures 10-13, 15, 19, 20, and 22-23 of this publication. In all the forms of application referred to two in-line wheels are together pressed by rotating friction rollers. This stresses the bogie considerably nor is this generally permitted by aircraft manufacturers. This is because bogies are in no way dimensioned to withstand a load pressing the axles together. Only in connec¬ tion with the final form of application, in Figures 19, 20, and 22-23, is one method of placing the friction rollers around the wheel shown. Bringing the transfer device straight from the side means that friction rollers can only be located on one side of this unit, which is highly impractical. A transfer device that grips the nose bogie wheels is shown in US Patent Publication 3,005,510. In this the bogie wheels next to each other are driven by means of two friction roller mats, which are wedged between the in-line bogie wheels. Here too a force is caused between the axles, which tends to force the axles apart. This invention presents a new type of bogie-gripping transfer device. The practical problems connected to a bogie-gripping transfer device are, among others: - the applicability of the transfer device to bogie wheels of different size and especially with different distances between the axles - the placing of the friction rollers around the bogie wheels and the removal of them a sufficient power for the transfer device and the mini¬ mization of the power of a single friction roller and the distribution of the power between several friction rollers. The latter problem is due to the fact that in practice aircraft using bogie wheels are so large that it is not possible to feed all the motive force to one or even in general to two of the tyres of the aircraft, because the point forces would then become too large. The distribution of the power to several friction rollers and several wheels there again causes the above-mentioned practical problems. On account of safety it is best if the largest force directed to the wheel is as small as possible. Thus it is as such natural to distribute the loading to several friction rollers. The intention of this invention is to create a transfer device rotating different kinds of bogie wheels, in which the afore¬ mentioned problems have been overcome. The characteristics of the invention appear in the accompanying Patent Claim 1. The main principle of the invention is to form a floating support for the friction rollers gripping the wheels of the second axle of the bogie. These are permitted a unified movement is location in a horizontal direction, by means of which they can be applied to an arbitrary distance between axles. In the form of applica¬ tion in accordance with Patent Claim 2 the symmetrical location of the friction rollers achieves the advantage that the greatest part of the compressive force caused by the torque is cancelled out. In addition symmetrical pairs of friction rollers are self- centering, when they are drawn towards one another. The form of application in accordance with Patent Claim 3 solves in a simple manner the pre-setting of the transfer device to sets of bogie wheels of different size. According to this the rear friction rollers can be driven up to the bogie wheels, when a clear fixed point for placing is created. This can be achieved even more advantageously in accordance with Patent Claim 5, when the same transfer device can be applied to dealing with a large range of differently sized bogie wheels. Placing takes place quickly, when the rear friction rollers are placed beforehand in a setting corresponding to the size of the bogie wheel. The form of application in accordance with Patent Claim 4 shows placing members for a transfer device, which only take up a small space longitudinally. Instead of the construction in accordance with Patent Claim 5 it is possible to completely replace one of the horizontal slides with a fixed support, which is attached to a horizontal beam. In this case the transfer device need only be driven to such a place that the centre rollers can be pushed in. In what follows the invention is illustrated with examples by reference to the accompanying Figures, which present one form of application of the invention. Figures l and 2 show the use of the transfer device in moving an aircraft Figure 3 shows the transfer device being driven round a set of bogie wheels Figure 4 shows the transfer device seen from in front Figure 5 shows the transfer device in the transfer position, attached to the bogie Figure 6 shows the situation in Figure 5 seen from above Figure 7 shows a cross-section of Figure 5 at I - I. In the situation shown in Figures 1 and 2 the transfer device 2 pushes the aircraft 1 from the right-hand side, fixed under¬ carriage bogie in which there is the set of bogies wheels 3. The pushing causes a turning moment around the left-hand side undercarriage, which is cancelled out by the lateral frictional force nosewheel 5 of the aircraft and the main undercarriage beneath the fuselage. Usually the aircraft 1 is pushed back¬ wards, when the transfer device 2 is brought around the set of bogie wheels from in front. It is also possible to push the aircraft 1 using the transfer device 2. In Figure 3 the transfer device 2 is being driven around the set of bogie wheels. The driver is not shown. Before attachment to the bogie wheels the steering of the transfer device 2 takes place by means of the steerable rear wheel 7. The other wheels 5 of the control cab frame 4 are then locked. Hydraulic motors are attached to these wheels for the independent movement of the transfer device 2. The transfer device 2 is composed of two main parts; the control cab frame 4 and the pairs of friction rollers and placing devices carried by the frame component 8, 18. The control cab frame 4 contains power and control devices. The power devices consist of a diesel motor and a hydraulic pump unit. In order that it is possible to drive the transfer device 2 around the set of bogie wheels 3, the front and middle friction rollers 14 have been moved to the side and the rear friction rollers 15 can be driven onto the bogie wheels 6. In Figure 4 this free line of movement is seen from in front. The rear friction rollers 15 are supported on both sides by the same axle 16, but a separate motor unit 13 has been arranged for both friction rollers 15. These are directly installed on the rear slides 9. The motor units of the front and middle friction rollers 14 are on the other hand installed on transverse slides 12 and these in turn in slides 10 and 11 that run in the frame 8 beam. Thus the lateral movement of the friction rollers 14 takes place by moving them along with the motor units 13 along slides 12. For this purpose a chain is arranged to run round the length of slide 12, the motor unit being attached to the chain. The chain is driven by a chain mechanism, which is driven from the longi¬ tudinal axle 26. This has a wedge groove formed in its entire length, by means of which the torque can be transmitted to the chain mechanism 25 as it moves with slide 10 or 11. The axle 26 is connected to the drive shaft from the gearbox of the drive motor 27 and drives all three slides 12 in the same row. The various dimensions of the set of bogie wheels 3 of the aircraft to be moved are generally known and in accordance with this the rear friction rollers 15 can be set to such a position before moving that the central slides 10 come exactly between the bogie wheels 6. The pre-setting of the slide 9 takes place by means of cylinder 24, which also locks to the desired place. When the set of bogie wheels 3 has been placed against the friction rollers 15, the middle and front friction rollers 14 are pushed in at the location of the wheels 6. Cylinders 23 and 24 are pushed completely out, when they push slides 10 and 11 to their extreme positions against stops 21 and 22. At this stage the frame 8 is still carried on wheels 17 and the lower end of the vertical slide 19 and the upper 14 and 15 are only slightly above the centre line of the wheel 6. Now pressure to draw in can be applied to cylinders 20 and 23, when the upper friction rollers touch first of all the wheels 6 and precisely from above their centre lines, when they raise the frame 8 and all friction rollers 14, 15 are symmetrically round the wheels 6, Figures 5, 6, and 7. The front of frame 8 is free to settle at a height determined by the wheels 6 by means of vertical slides 19. After this the friction rollers 14 and 15 are rota¬ ted, when the wheels 6 are made to rotate and the entire air¬ craft made to move. The pressure of the friction wheels 14 and 15 against the wheel 6 is created by drawing the front slides 10 and 15 together by means of cylinder 20 and the second last slide 10 backwards by means of cylinder 23. The outputs of cylinders 20 and 23 are arranged to be equally great, in which case the same static pressure is applied to all friction wheels 14 and 15. The torque supplied to friction rollers 14 and 15, however, disturbs this power symmetry. Each friction roller must be pressed against wheel 6 with such a great force, that the necessary transfer of the friction force to wheel 6 is in general possible. During the transfer stage the wheels 5 and 7 of the transfer device turn freely as the set of bogie wheels 3 turns and wheels 26 are in the air.

Claims: Patent Claims 1. A transfer device (2) that grips bogie wheels (6), which is intended to move an aircraft (1) or other wheeled device over a base, which transfer device (2) includes a frame section (8, 18) and, supported on this, friction rollers (14, 15) that grips two or four in-line bogie wheels (6) and rotate them and the motors that drive them (13), each wheel (6) having at least three friction rollers (14, 15), and pressure devices (20, .23) to press the friction rollers (14, 15) against the wheel (6) , and which transfer device (2) includes a power device and transmission devices to feed the power to the motors (13) and devices to place the friction rollers (14) around the wheels and to remove them, characterized in that the placing devices of the friction rollers (14) that grip the wheels (6) of the second axle of the set of bogie wheels (3) is connected to one or more horizontal slides attached to the frame (8) , so that the fric¬ tion rollers (14, 15) are able to settle in a position in accordance with the distance between the axles of the set of bogie wheels (3) and that their pressure devices (20) are arranged to create a mutual drive force in the friction rollers (14) , which presses them against the wheels (6) of the aforemen¬ tioned second axle or against the wheel in the case of a trans¬ fer device that grips only two in-line wheels. 2. A transfer device (2) in accordance with Patent Claim 1, which includes a U-shaped frame section (8, 18), which is driven around the set of bogie wheels (3), characterized in that both sides of the transfer device (2) have eight friction rollers (14, 15) , which are connected as four pairs of upper and lower roller to support devices, at least three of which have horizontal slides (9, 10, 11) attached to the frame (8) to move the friction rollers (14) against the wheels (6), and in which the support members are arranged to place the friction rollers (14, 15) symmetrically horizontally and vertically around each wheel (6) and that the pressure devices include hydraulic cylinders (20, 23), which are arranged to pull the horizontal slides (10, 11) with an equal force. 3. A transfer device (2) in accordance with Patent Claim 2, characterized in that the rear right and left- hand friction rollers (15) are connected to rotate on a common transverse axle (16) and that they are placed in a fixed position laterally and that they are made broader than the other friction rollers to permit the driving of several various sizes of bogie wheels. 4. A transfer device (2) in accordance with Patent Claim 3, characterized in that the setting devices of the friction rollers (14) in front and in the middle include lateral movement slides (12) by means of which these friction rollers (14) are made to move laterally away from the track of the set of bogie wheels (3) and on the other hand round the wheels (6) of the set of bogie wheels (3) when the U-fork is in place. 5. A transfer device (2) in accordance with Patent Claims 2, 3, or 4, characterized in that all four pairs of friction rollers are supported on horizontal slides (9, 10, 11), between the front (10, 11) and second last of which and the frame (8) hydraulic cylinders (20, 23) are connected, the power of which is arranged to be equally great and of which the rear one (9, 10) is connected by means of a locating device, for example a hydraulic cylinder (24) , to the frame (8) , which locating device is arranged to place and lock the friction rollers (14) in a preset position corresponding to the size of the set of bogie wheels (3) . 6. A transfer device (2) in accordance with Patent Claims 2, 3, or 4, characterized in that three pairs of friction rollers are supported on horizontal slides and one in a fixed position in the horizontal direction, between two of which, forming a pair between the horizontal slide and between the third horizontal slide and the frame hydraulic cylinders are connected, the tractive power of which is arranged to be essen- tially equal.

Inventors: SINKKONEN MATTI, SINKKONEN, MATTI
Applicants: TANA JYRAE KY, TANA-JYRAE KY
Application year: 1990
Main classification: B60S13
IPC codes: B64F1