GB2147554A

GB2147554A - Test unit for gearboxes

Info

Publication number: GB2147554A
Application number: GB08423468A
Authority: GB
Inventors: Eric Albert Whateley
Original assignee: BROWN GEAR IND; David Brown Gear Industries Ltd
Current assignee: BROWN GEAR IND; David Brown Gear Industries Ltd
Priority date: 1983-10-05
Filing date: 1984-09-17
Publication date: 1985-05-15
Also published as: GB8423468D0; GB8326691D0; GB2147554B

Abstract

A mobile test unit for testing a gearbox 41 comprises a four-wheel-drive truck with enclosed body 24. The gearbox 41 is secured in a wheeled cradle 42, raised by lift 40 to the floor level of the body 24, moved forwards, and clamped to resiliently mounted beams 44. An oil cooler is connected to the gearbox 41 via a flowmeter. The gearbox 41 is then driven by the truck's engine 11 via a power take- off 16 on the truck's transfer gearbox 15, a drive 39 passing through the floor, and shafting 35, 36, 46 incorporating a torque meter 37. A control room at the front of the body 24 has an instrumentation console 27 which indicates the metered values. <IMAGE>

Description

SPECIFICATION Test unit for gearboxes The invention relates to a test unit for gearboxes, and more particularly for large gearboxes such as those for heavy vehicles, and has for its object to provide a fully mobile and self-contained test unit therefor.

According to one aspect of the invention, a mobile test unit for large gearboxes comprises a wheeled truck having an engine for driving at least some of the wheels and also arranged to drive a gearbox to be tested when said gearbox is temporarily supported on the truck.

According to another aspect of the invention, a mobile test unit for large gearboxes comprises a wheeled truck having an engine, gearing for transmitting drive from the engine to at least some of the wheels and also provided with a power take-off, a driver's cab, a body adapted to support temporarily a gearbox to be tested, power transmission means driven by the power take-off and adapted to drive a gearbox to be tested when said gearbox is supported in the body, test means incorporated in the power transmission means, and test instrumentation for indicating the results obtained from the test means.

A preferred embodiment of the invention will now be described, by way of example.

with reference to the accompanying semidiagrammatic drawings of which: Figure 1 is a side elevation of a truck adapted for use as a mobile test unit for large gearboxes with such a gearbox supported therein, the near side of the truck body being omitted for clarity; Figure 2 is a plan view of the truck with a gearbox under test supported therein, the roof of the truck body being omitted for clarity; Figure 3 is a view of the interior of the truck body with a gearbox under test supported therein, in the direction of the arrow 3 in Fig. 1; and Figure 4 is a view of the interior of the truck body with a gearbox under test supported therein, in the direction of the arrow 4 in Fig. 1.

Referring now to the drawings, -a fully mobile and self-contained test unit for large gearboxes such as those for heavy vehicles is based on a four-wheel-drive truck. The truck has a chassis 10 in which there are disposed an internal combustion engine 11, a friction clutch 1 2 for disengageably driveabiy connecting the engine 11 to a variable-speed gearbox 13, a first propeller shaft 1 4 driveably connecting the variable-speed gearbox 1 3 to a transfer gearbox 1 5 having a power take-off 16, a second propeller shaft 1 7 driveably connecting the transfer gearbox 1 5 to a driven rear axle 1 8 having two pneumatictyred wheels 19, a third propeller shaft 20 driveably connecting the transfer gearbox 1 5 to a driven front axle 21 having two pneumatic-tyred wheels 22, a driver's cab 23 mounted at the front of the chassis 10 and having conventional controls for the truck, and an enclosed body 24 mounted on the chassis 10 behind the cab 23. The transfer gearbox 1 5 contains ciutch means enabling the drive to the second and third propeller shafts 1 7 and 20 to be disengaged whilst maintaining a drive to the power take-off 1 6.

A partition wall 25 including a window 26 separates a smaller front part of the body 24 from a larger rear part thereof having rear double doors 63, the front part forming a control room having a console 27 containing test instrumentation supplied with electrical power by a generator 28 driven by the engine 11, a test operator's seat 29, a translucent roof panel 30, a ventilator fan 31, a door 32 leading outside, and a door 33 leading to the rear part of the body 24. Not far to the rear of the partition wall 25 and midway between the sides of the body 24 there is resiliently mounted on the floor of the body 24 a pedestal 34 in which there are journalled two short horizontal shafts 35 and 36 aligned on a common fore-and-aft axis.A torque meter 37 is driveably interposed between the shafts 35 and 36, and the front one 35 of said shafts is driveably connected by a gear-type coupling 38 to drive means 39 which pass through the floor of the body 24 to the power take-off 1 6. A lift 40 operated by power derived from the engine 11 is provided at the rear of the body 24 to raise from and lower to ground level a gearbox 41 to be tested, said gearbox being temporarily secured in a cradle 42 having wheels 43. Two support beams 44 are resiliently mounted rearward of the pedestal 34 on the floor of the body 24, parallel to and equally spaced from its sides, and two grooves 45 in the floor forming guides for the wheels 43 of the cradle 42 extend from the rear of the body 24 to the front ends of the beams 44, the grooves 45 being disposed between, close to and equidistant from the beams 44.Two grooves 66 aligned with the grooves 45 are formed in the lift 40. The beams 44 are adapted to be so clamped to the cradle 42 by bolts 67, when it is positioned between them, as to raise its wheels 43 clear of the floor of the body 24. A fourth propeller shaft 46 driveably connected to the rear one 36 of the shafts journalled in the pedestal 34 is adapted to be driveably connected to the input shaft 47 of the gearbox 41 to be tested, and a guard 48 for the propeller shaft 46 is slideable into and out of operative position on a bracket 49 projecting rearwardly from the pedestal 34.An oil cooler for the gearbox 41 to be tested comprises a radiator 50 secured alongside a louvred panel 51 in that side of the body remote from the door 33 in the partition wall 25, a rigid inlet conduit 52 connected to the radiator 50 and having a manual changeover filter assembly interposed in it, and a rigid outlet conduit 53 connected to the radiator 50 and having a turbine flowmeter 54 interposed in it. The manual changeover filter assembly comprises two filters 55 with manually operable valve means 56 for causing the oil to flow through either one of them, so that the other can be changed or cleaned without interrupting a test.The inlet conduit 52 has connected to it a first flexible hose 57 adapted to be connected to an oil outlet 64 of the gearbox 41 to be tested, and the outlet conduit 53 has connected to it a second flexible hose 58 adapted to be connected to an oil inlet 65 of the gearbox 41. A fan 59 disposed on that side of the radiator 50 remote from the louvred panel 51 is driven by an electric motor 60 supplied with power by the generator 28. A ventilator 61 and translucent panels 62 are provided in the roof of the rear part of the body 24. The torque meter 37 and the flow-meter 54 are connected to the test instrumentation in the console 27.

In operation, the truck is driven to the location of the gearbox 4' to be tested, said gearbox is secured in the cradle 42, the lift 40 at the rear of the truck is lowered and the cradle 42 is moved on to it with the wheels 43 engaged in the grooves 66, the lift 40 is raised and the cradle 42 is moved along the grooves 45 into its required position relative to the support beams 44, said beams are clamped to the cradle 42 thereby raising it and the gearbox 41 to be tested into a resiliently supported position clear of the floor of the body 24, and the fourth propeller shaft 46 and the first and second flexible hoses 57 and 58 are connected to the gearbox 41.The engine 11 of the truck is then caused to drive the gearbox 41 to be tested by way of the friction clutch 1 2, the variable-speed gearbox 13, the first propeller shaft 1 4, the power take-off 1 6 of the transfer gearbox 15, the drive means 39 passing through the floor of the body 24, the gear-type coupling 38, the front one 35 of the shafts journalled in the pedestal 34, the torque meter 37, the rear one 36 of the shafts journalled in the pedestal 34, and the fourth propeller shaft 46. The torque meter 37 measures the power lost in driving the gearbox 41 to be tested, and the power loss so measured is indicated by the test instrumentation in the console 27.

In a modification, the truck has only its rear axle driven and no transfer gearbox is therefore required, the power take-off being incorporated in the variable-speed gearbox and driveably connected by another propeller shaft to the drive means passing through the floor of the body. In another modification, the control room is dispensed with and the console containing the test instrumentation is disposed in the driver's cab.

Claims

1. A mobile test unit for large gearboxes comprising a wheeled truck having an engine for driving at least some of the wheels and also arranged to drive a gearbox to be tested when said gearbox is temporarily supported on the truck.

2. A mobile test unit for large gearboxes comprising a wheeled truck having an engine.

gearing for transmitting drive from the engine to at least some of the wheels and also provided with a power take-off. a driver's cab.

a body adapted to support temporarily a gearbox to be tested, power transmission means driven hy the power take-off and adapted to drive a gearbox to be tested when said gearbox is supported In the body, test means incorporated in the power transmission means. and test instrumentation for indicating the results obtained from the test means.

3. A mobile test unit according to claim 2.

wherein the gearing comprises a variablespeed gearbox In series with a transfer gearbox which provides four-wheel drive and also incorporates the power take-off.

4. A mobile test unit according to claim 2 or claim 3, wherein the power transmission means comprise drive means connected to the power take-off and shaft means journalled in a pedestal n the body and connected to the drive means.

5. A mobile test unit according to claim 4, wherein the pedestal is resiliently mounted on the floor of the body.

6. A mobile test unit according to claim 4 or claim 5, wherein the drive means include a gear-type coupling.

7. A mobile test unit according to any one of claims 4 to 6, wherein the test means include a torque meter driveably interposed between two axially-aligned shafts which constitute the shaft means.

8. A mobile test unit according to any one of claims 2 to 7, wherein the test instrumentation is housed in a control room disposed in the body and is supplied with electrical power by a generator driven by the engine.

9. A mobile test unit according to any one of claims 2 to 8, wherein an oil cooler for the gearbox to be tested is disposed in the body and comprises a radiator having inlet and outlet pipework adapted to be connected to said gearbox and a fan driven by an electric motor supplied with power by a generator driven by the engine.

10. A mobile test unit according to claim 9, wherein the test means include a flowmeter interposed in the pipework associated with the radiator.

11. A mobile test unit according to any one of claims 2 to 1 0, wherein a lift operated by power derived from the engine is provided on the body to raise and lower a gearbox to be tested from and to ground level.

1 2. A mobile test unit according to any one of claims 2 to 11, wherein support beams for the gearbox to be tested are mounted on the floor of the body and adapted to be so clamped to a wheeled cradle in which said gearbox is temporarily secured as to raise the wheels of the cradle clear of the floor of the body.

13. A mobile test unit according to claim 12, wherein the support beams are resiliently mounted on the floor of the body.

1 4. A mobile test unit according to claim 1 2 or claim 13, wherein grooves in the floor of the body are adapted to guide the wheels of the cradle to facilitate movement of the cradle into and from its required position relative to the support beams.

1 5. A mobile test unit for large gearboxes constructed, arranged and adapted to operate substantially as hereinbefore described with reference to, and as illustrated by, the accompanying drawings.