Drive wheel roller

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to drive wheels on a shaft and more particularly to wheels which can be fixed to the drive shaft or rotate freely on the drive shaft.

2. Description of the Related Art

In many powered devices wheels are directly connected by a drive shaft to a motor. There are no clutches, speed changing gears or reverse gears to keep the cost and weight of the device down. When the motor is on, the wheels are powered by a direct connection from the motor through the drive shaft to the wheels. When the power is off the device becomes hard to push or pull since the wheels and the drive shaft are still connected to the motor. Some devices have a second set of wheels used when pushing or pulling the device. These wheels may be used when the device is tilted onto the second set of wheel by pushing the handle used for pushing and pulling the device downward and raising the drive wheels off the ground. The tilting requires quite a bit of effort to keep the drive wheels off the ground while pushing or pulling the device.

It is desired to have a device, which can easily be pushed or pulled on its drive wheels when the motor is off.

SUMMARY OF THE INVENTION

A drive shaft is attached to a motor and to a pair of drive wheels on other side of a motor driven device. A roller bearing placed between the drive wheel and the shaft can be used to rotate the wheel on the drive shaft without turning the drive shaft. The a wheel hub connected to the wheel has a pin through it and the drive shaft to stay fixed to the drive shaft when the motor is driving the device. The pin can be removed from the wheel hub and the drive shaft when it is desired to have the drive wheels turn freely to push or pull the device. By removing a pin for each wheel both wheels can turn freely to push or pull the device. When the device has power available again the pins can be reinserted and the device driven by the motor again.

OBJECTS OF THE INVENTION

It is an object of the invention to easily disengage a wheel from a drive shaft so that it can rotate without rotating the drive shaft.

It is an object of the invention to easily push or pull a motor driven device having a direct drive from the motor to the drive shaft when the motor is not on.

It is an object of the invention to retrofit old devices with the disengageable wheels.

Other objects, advantages and novel features of the present invention will become apparent from the following description of the preferred embodiments when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1

is a cut away side view of the axle bearing wheel hub and screw cap

FIG. 2

is a side view of the axle.

FIG. 3

is a side view of the wheel hub.

FIG. 4

is a side view of a pin with a looped top.

FIG. 5

is a side view of a bail pin.

FIG. 6

is a perspective view of the drive wheel roller installed on a floor stripping machine.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1

shows a drive axle

15

which is directly connected to a motor. The drive axle

15

has a bearing

20

rotatingly attached to the axle. A wheel

40

is attached to the bearing

20

and a tire

45

is attached to the wheel. A hub

25

is attached to the wheel

40

along coplanar portions

42

,

43

. A gap

38

allows the hub

25

to spin on axle

15

. The axle

15

and hub

25

have apertures

30

and

32

respectively which when aligned allow for a pin

50

or

70

to pass therethrough locking the rotation of the hub

25

and the axle

15

together. When pin

50

or

70

is removed the wheel

40

can rotate on the axle

15

freely and independently of the axle's rotation. A screw cap

35

having a screw

36

threaded into the axel

15

engages the axle to keep the wheel

40

in place. The screw cap

35

can be easily removed to remove the wheel

40

if desired by unscrewing screw

36

from the axle

15

. When the screw cap

35

is attached to the axle

15

a small gap

37

will exist between the hub

25

and the screw cap

35

.

When using a device with an axle

15

directly connected to the wheels

40

and the drive motor

60

is on the wheels

40

will turn and propel the device

100

. When the drive motor

60

is off it is hard to move the device

100

when it is resting on the wheels

40

, since turning the wheels

40

by pushing or pulling on the device

100

also turns the motor

60

. When the motor

60

is off such as when the device

100

is being transported to a work location, the pins

50

can be pulled from the hubs

25

and axle

15

to allow the wheels

40

to spin on bearing

20

without being connected to the wheel

40

by way of hub

25

being rotatingly connecting to the axle

15

. The device

100

can now be easily moved by pushing or pulling on it without having to turn motor

60

.

The pin

50

preferably has a ring

51

at the top for easily pulling the pin

50

from the apertures

30

,

32

in the axle

15

and the hub

25

. The pin

50

may have a flared ends

52

for keeping the pin from falling out of the apertures

30

,

32

or use other means for preventing the unwanted withdrawal of the pin

50

. Alternatively spring pin

70

having a bail portion

71

may be used for attaching the hub

25

to the axle

15

.

Although a screw cap

35

with a screw

36

is shown engaging the axle

15

to keep the wheel

40

from coming off the axle any device serving the same function may be used. Similarly even though a pin

50

or

70

is shown extending through apertures

30

,

32

of the axle

15

and the hub

25

any means of locking and unlocking the axle

15

and the wheel

40

may be used.

It is preferred to use a bearing

20

having axial cylinders in the bearing race however any bearings for supporting the weight of the device while rotating the wheels on the axle are within the scope of the invention.

It is easy to retrofit the axle and drive wheel roller on an existing device

100

such as a floor stripping machine as shown in

FIG. 5

by replacing the exiting axle on the floor stripping machine with an axle

15

having an aperture

30

. Then installing a wheel

40

having a bearing

20

and a hub

25

with aperture

32

.

Although the device

100

shown in

FIG. 5

has an electric motor

60

any type of motor may be used.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.