Driving device for a vehicle cab tilt pump

TECHNICAL FIELD

This invention relates to a drive for a vehicle cabin tilt pump having a force- actuatable shaft end being drivable back and forth for its operation.

BACKGROUND

During maintenance of commercial vehicles having cabins that can be tilted to a raised position, such a tilt pump is used to drive a fluid motor capable of raising the cabin to a servicing position and possibly also of lowering the cabin to its normal position. The pump is normally operated by manual pumping movements using a pump lever that is attached to the actuatable shaft end. This manual pumping operation, however, requires much effort and may also cause spinal and shoulder pain in persons working on a daily basis with maintenance of vehicles having tillable cabins. Other known types of vehicle cabin tilt pumps, for example shown in EP-

1293418-A1 and FR-2743047-A1 , have a rotatable shaft end for a rotational type pump and is then actuatable by a rotating power tool, such as power screw/nut driver. There is, however, a need to be capable of driving also a pump having a shaft end that is drivable back and forth for its operation by such a power tool.

DISCLOSURE OF THE INVENTION

An object of the invention is therefore to provide a drive of the above described kind which can be operated by a rotating power tool.

According to one aspect of the invention, the drive comprises a housing being formed as an adapter for a rotating power tool and being releasably connected to the pump. Thereby, the device needs not be accessible on each vehicle but may be portable and available for the operators that must often use the pump. The adapter has a rotatable input end for engagement with the rotating power tool, an output end for engagement with the drivable shaft end, and a mechanism for converting rotational movement of the input end to a back and forth movement of the output end for the operation of the pump.

In one embodiment the mechanism is adapted to convert the rotational movement of the input end to a back and forth movement in a plane of the output end. The output end may then be adapted for driving engagement with the force-actuatable

shaft end by driving engagement in a radial sleeve that is rigidly connected to the shaft end.

In that embodiment, the mechanism comprises a disc rotatably supported in the housing and drivable from the input end. A lateral face of the disc has an encir- cling eccentric groove. A rocker arm has a first end received in said groove for causing a rocking motion of the rocker arm when the disc rotates, and a second, opposite end of the rocker arm then forms the output end of the housing.

In that embodiment, the disc may comprise a gear wheel included in a gear transmission driven from the input end. A gear reduction and a suitable adaptation to the possibly limited torque of the power tool may thereby be obtained.

According to another embodiment, the mechanism is adapted to convert the rotational movement of the input end to a back and forth rotational movement of the output end. The output end may then be adapted for drive engagement with the ac- tuatable shaft end by a direct drive engagement with the shaft end. In that case the mechanism comprises a connection rod adapted, through a crank shaft, to convert a unidirectional rotational movement at the input end to a back and forth movement at the output end.

The housing may comprise a plurality of angled surfaces for shape-engaging connection to the pump. These angled surfaces may then at least partially enclose the pump so that the operator may be relieved from the task of securely holding the adapter to the pump.

Other features and advantages with the invention are apparent from the claims and the following description of embodiments.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a diagrammatic lateral view, partly in section, of a first embodiment of a drive according to the invention connected to one type of a cabin tilt pump;

FIG. 2 is a diagrammatic view obliquely from below of a drive approximately according to FIG. 1 ; FIG. 3 is a view corresponding to FIG. 1 , with portions broken away, showing the drive in an operational state different from that of FIG. 1 ; and

FIG. 4 is a view corresponding to FIG. 3, of an alternative embodiment of a drive according to the invention connected to another type of a cabin tilt pump.

DETAILED DESCRIPTION OF EMBODIMENTS

FIG.1 shows a fluid powered cabin tilt pump 60 that, in a manner not closely shown, is securely mounted to a side of a diagrammatically depicted vehicle 70. A cabin 72 is tiltably mounted to the vehicle 70 and tiltable between a lowered normal position and a raised service position by means of a fluid powered motor 74, such as a hydraulic cylinder. The motor 74 is adapted to be driven by the pump 60 through a pressurized fluid via conduits 76, 78. In the example shown, the motor 74 is a double acting hydraulic cylinder but may in the scope of the invention be of any other known type. At a face thereof, the pump 60 has a protruding shaft end 62 that in the example of FIG. 1 is rigidly connected to a radially oriented sleeve 64. To operate the pump 60, a manual pump lever (not shown) is conventionally used, where one end thereof is inserted into the sleeve 64, whereupon an operator is able to drive the motor 74 by the pump 60 with back and forth pumping movements in order to tilt the cabin 72 to the raised position. The lowering of the cabin 72 to the normal position may be accomplished, for example by operating a valve (not shown) for return flow of the pressurized fluid.

According to the invention, for the actuation of the pump 60 there is instead used a portable drive in the shape of an adapter 10 for a rotating power tool (not shown) such as a rechargeable power screw driver.

The adapter 10 has a housing 12 formed for shape-engagement with the pump. As is more closely apparent from FIG. 2, to this end the housing 12 can have a plurality of surfaces 13, 14, 15, 16, which partially envelope the pump 60 and more or less retain the housing 12 to the pump 60 so that the operator is relieved from this task. To completely arrest the housing 12 to the pump 60, the housing 12 can also have a clamping device 80 in the shape of a tensioning band or strip 82 having one end firmly connected to the housing 12 and the other end provided with a hook 84 to be hooked onto a rear face of the pump 60. The tensioning band 82 may also have a tensioning means 86 of a known type. The housing 12 of the adapter 10 has an input end 20 for operative engagement with the above-mentioned rotating power tool, and an output end 50 for operative engagement with the force-actuatable shaft end 62 of the pump 60. In the examples shown, the input end 20 is provided with a hexagonal drive pin 22 to be driven by a hexagonal socket (not shown) of the power tool.

The housing 10 of the adapter has therein a mechanism 30 for converting a unidirectional rotation movement of the input end 20 to a back and forth movement of the output end 50.

In the example according to FIGS. 1-3 the mechanism 30 comprises a gear transmission having a pair of inter-engaging gear wheels 32, 36. As is apparent from FIGS. 1 and 3, one gear wheel 32 is rotatably supported in the housing 12 through a shaft 34, one end of which forms the above-mentioned input end 20 of the adapter 10. The other, larger gear wheel 36 is also rotatably supported in the housing 12 through a shaft 38 and comprises a disc having an eccentric encircling, for example circular, guiding groove 40 in one side thereof for a rocker arm 42. The rocker arm 42 is pivotably supported in the housing 12 about an axis 44 extending perpendicularly to the shafts 34, 38 of the gear wheels. An inner spherical end 46 of the rocker arm 42 is received in the guiding groove 40, and an outer spherical end of the rocker arm 42, forming the above-mentioned output end 50, protrudes out of the housing 12 through an elongated opening 18. When the gear wheels 32, 36 are brought into rotation by the above-mentioned power tool at the input end 20, it will be recognized that the inner end 46 (FIG. 1 ) of the rocker arm 42, guided in the guiding groove 40, will perform a back and forth oscillating movement about the axis 44 so that the output end 50 also performs a back and forth oscillating movement at the outside of the housing 12.

When the adapter 10 of FIGS. 1 and 3 is mounted by the above-mentioned shape-engaging connection to the pump 60, the output end 50 thereof engages into the sleeve 64 of the force-actuatable shaft end 62 of the pump 60. When the adapter 10 is operated by the rotating power tool, the oscillating movement of the output end 50 will accordingly be transformed to the sleeve 64 that in turn operates the shaft end 62 of the pump 60 by a back and forth pumping movement.

In the embodiment according to FIG. 4, the adapter 10 is adapted to a pump 60 of the well-known type that does not have any radial sleeve at the force- actuatable shaft end 62 thereof, but the shaft end is instead shaped with a hexagonal driving pin 66 that conventionally is adapted to be brought into pumping movement by a manual pump lever (not shown), the corresponding end of which has a laterally oriented hexagonal socket.

The adapter 10 according to FIG. 4 also has an input end 20 provided with a hexagonal pin 22 that protrudes from a shaft 34' rotatably supported at the housing

12. In this case, the mechanism 30 is a crank mechanism, and the shaft 34' is a crankshaft that supports a crank pin 52 via a flywheel 32'. At the crank pin 52, one end of a connection rod 54 is supported, the other end of which is supported at a pivot pin 56 of a flywheel 36' that is supported by a shaft 38' in turn supported in the housing 12. The arrangement is such that when the crankshaft 34' is brought into unidirectional rotation by the rotating power tool (not shown), the crank pin 52 performs a rotational movement that is converted via the connection rod 54 and the pivot pin 56 to a back and forth oscillating rotational movement of the flywheel 36' and thereby of the shaft 38'. Accordingly, the pivot pin 56 is located at such a distance from the shaft 38', that it performs only a back and forth circular arc movement. The shaft 38' rotationally supported at the housing 12 extends through an opening in the housing 12 by an end that forms the output end 50 of the adapter 10, and in this case is formed with a hexagonal socket for driving engagement with the hexagonal driving pin 66 of the pump 60. As the pump 60 in the embodiment of FIG. 4 is operated by a back and forth rotational movement, it may be sufficient if the housing 12 of the adapter 10 is in enclosing shape-engagement with the pump 30 by only one or a few surfaces, such as the surfaces 15, 17, which prevent only the housing 12 of the adapter 10 to be rotated relative to the pump 60 during operation. The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom. Modifications will become obvious to those skilled in the art upon reading this disclosure and may be made without departing from the spirit of the invention or the scope of the appended claims.