Drive system

• US 5,335,740 A
• Filed: 07/02/1993
• Issued: 08/09/1994
• Est. Priority Date: 11/29/1989
• Status: Expired due to Term

• Current Assignee: The Scott Fetzer Company (Berkshire Hathaway Incorporated)
• Original Assignee: The Scott Fetzer Company (Berkshire Hathaway Incorporated)
• Inventors: Meyer, Robert B., Lackner, John R., Matuschek, Hans J.
• Primary Examiner(s): HILL, MITCHELL
• Application Number:
  US08/088,095
• Time in Patent Office: 403 Days
• Field of Search: 180/19.1, 180/19.2, 180/19.3, 192/113 A, 74/376, 74/473 R, 15/340.2, 15/340.3, 15/329
• US Class Current: 180/19.1
• CPC Class Codes: A47L 5/28 Suction cleaners with handles and nozzles fixed on the casings, e.g. wheeled suction cleaners with steering handle A47L5/24 takes precedence
• CPC Class Codes: A47L 9/009 Carrying-vehicles; Arrangements of trollies or wheels; Means for avoiding mechanical obstacles
• CPC Class Codes: B62B 5/0073 Measuring a force

Abstract

A transmission for a wheeled appliance responsive to pushing and pulling forces applied to a handle. The transmission includes speed reduction gearing and forward and reverse clutching elements which provide high power capacity, large speed reduction, durability, quiet operation and smooth power engagement. The main power train elements all rotate on parallel axes and the forward and reverse clutching elements are essentially independent of one another and resistant to wear.

Claims

1. A reversible drive system for a wheel supported device comprising an input pinion and a pair of constantly meshed counter-rotating gears, the input pinion being in driving engagement with one of said gears, said counter-rotating gears each being supported for rotation about a respective axis parallel to the axis of the other, a pair of sprockets respectively associated with the pair of counter-rotating gear to form first and second sets, means supporting each sprocket in confronting relation to a respective gear and for rotation about its said respective axis, first and second clutching surfaces respectively for the first and second gear and sprocket sets, a common sprocket supported for rotation about an axis parallel to said gear axes, a belt trained around both of said pair of sprockets and said common sprocket, an output shaft operatively connected to said common sprocket and adapted to drive the wheels of the device in forward or reverse rotation as determined by the rotational direction of the sprockets, and clutch actuation means responsive to a manually developed force in a first direction to clutch the first set of said gears and sprockets together through their respective clutching surfaces to drive said sprockets in a first rotary direction and direction opposed to said first direction to clutch the second set of said gears and sprockets together through their respective clutching surfaces to drive said sprockets in a second rotary direction.

2. A drive system as set forth in claim 1, wherein said common sprocket is associated with a bevel gear, a second bevel gear meshing with said first mentioned bevel gear being drivingly mounted on the output shaft.

3. A drive system as set forth in claim 1, wherein said sprockets have grooves that are parallel to said respective axes and said belt is provided with teeth proportioned to engage said sprocket grooves.

4. A drive system as set forth in claim 1, including overload clutch means on said output shaft to prevent excessive torque being applied to said shaft.

5. A drive system as set forth in claim 1, wherein said clutching surfaces include an annular body of friction material.

6. In a wheeled appliance having a reversible, variable speed, power assist, an improved power assist control comprising:

a) a handle support on the appliance for longitudinal movement from a neutral position in forward and reverse directions along a path of power assisted appliance movement;

b) a handle connected to the handle support for transmitting forward and reverse forces to the support to cause such longitudinal movement from the neutral position;

c) a transmission having forward and reverse clutches, the clutches each having disengaged positions;

d) a transmission control linkage interposed between the support and the clutches for transmitting direction control forces from the support to the transmission via one of the clutches; and

e) biasing means urging the control linkage and the clutches into the neutral and disengaged positions.

7. The control of claim 6 wherein an output speed of the transmission is proportional to movement of the handle support from the neutral position.

8. The control of claim 6 wherein the handle is pivotally carried by the handle support.

9. The control of claim 6 wherein the handle support is reciprocatably mounted on the appliance.

10. The control of claim 6 wherein the handle support is a carriage journaled for rectilinear movement.

11. The control of claim 6 wherein the linkage includes at least one spherical connection.

12. A reversible drive system for a wheel supported device comprising:

a) an input gear and a pair of meshed counter-rotating gears driveably connected to the input gear;

b) said counter-rotating gears each being supported for rotation about a respective axis parallel to the axis of the other;

c) a pair of transmission output elements respectively associated with the counter-rotating gears to form a pair of sets;

d) means supporting each transmission output element in confronting relation to the associated counter-rotating gear of its set for rotation about the axis of its associated gear;

e) clutching surfaces for each gear and output element set;

f) flexible power transmission means trained around each of said output elements and a driven element;

g) an output shaft operatively connected to said driven element and adapted to drive at least one of the wheels of the device in forward or reverse rotation as determined by the rotational direction of the output elements; and

h) clutch actuation means responsive to a manually developed force in a first direction to clutch one set of said counter-rotating gears and elements together through said one set'"'"'s clutching surfaces to drive said output elements in a first rotary direction and responsive to a manually developed force in a second opposite direction to clutch the other set of said counter-rotating gears and output elements together through the other set'"'"'s clutching surfaces to drive said output elements in a second rotary direction to cause said shaft to selectively drive said at least one wheel in either forward or reverse directions.

13. A drive system as set forth in claim 12, wherein said driven element is associated with a first bevel gear, a second bevel gear meshing with said first bevel gear being drivingly mounted on the output shaft.

14. A drive system as set forth in claim 12, wherein said output elements are sprockets having grooves that are parallel to said respective axes and said flexible power transmission means is a belt provided with teeth proportioned to engage said sprocket grooves.

15. A drive system as set forth in claim 12, including overload clutch means on said output shaft to prevent excessive torque being applied to said shaft.

16. The drive system of claim 12;

wherein the transmission output elements and the driven element are sprockets and the power transmission means is a belt.

17. A drive system for a wheel supported device comprising:

a) an input pinion;

b) a rotatable gear in driving engagement with said pinion;

c) a sprocket associated with said gear on a common rotation axis;

d) means supporting said sprocket in confronting relation to said gear for rotation about said common axis;

e) clutching surfaces for said gear and sprocket;

f) a driven element supported for rotation about an axis parallel to said common axis;

g) a belt trained around said sprocket and said driven element;

h) an output shaft operatively connected to said driven element and adapted to drive at least one wheel of the device in rotation in response to the rotation of the sprocket and driven element; and

i) clutch actuation means responsive to a manually developed force to engage said gear and sprocket together through said clutching surfaces rotatably to drive said sprocket, said driven element and said gear being free to rotate relative to said sprocket when said clutching surfaces are disengaged.

18. A drive system as set forth in claim 17, wherein said driven element is operatively connected to a first bevel gear and a second bevel gear is drivingly mounted on the wheel shaft and meshed with said first bevel gear.

19. A drive system as set forth in claim 17 including overload clutch means on said output shaft to prevent excessive torque being applied said shaft.

20. A drive system as set forth in claim 17 wherein said clutching surfaces include an annular body of friction material.

21. A drive system for a wheel supported device comprising:

a) an input gear and an intermediate output gear drivably connected to the input gear, the gears constantly rotating during operation of the device;

b) a transmission output element associated with the intermediate gear to form a gear and output element set;

c) means supporting said output element for rotation about the axis of the intermediate gear;

d) clutching surfaces for said gear and output element set;

e) flexible power transmission means trained around each of said output element and a driven element;

f) an output shaft operatively connected to said driven element and adapted to drive at least one of the wheels of the device in forward rotation; and

g) clutch actuation means responsive to a manually developed force to clutch said set together through said clutching surfaces thereby causing said output element to rotate with said gears to cause said shaft to drive said at least one wheel during operation of said device.

22. A drive system as set forth in claim 21, wherein said driven element is operatively connected to a first bevel gear, and a second bevel gear is drivingly mounted on the output shaft and meshed with said first bevel gear.

23. A drive system as set forth in claim 21, including overload clutch means on said output shaft to prevent excessive torque being applied to said shaft.

24. The drive system of claim 21 wherein the elements are sprockets and the power transmission means is a belt.

25. A drive system for a self-propelled, wheeled device having a prime mover comprising:

a) an input gear operatively connected to said prime mover and rotatable about an axis;

b) an intermediate gear meshed with said input gear and rotatable about an axis to provide continuous rotation during operation of said prime mover;

c) a sprocket axially aligned and associated with said intermediate gear;

d) flexible power transmission means trained around said sprocket and a driven element, said driven element being operatively connected to an output shaft which is drivingly connected to at least one of said wheels of said device;

e) clutching means associated with said sprocket via a frictional coupling for clutching said sprocket and said intermediate .gear in driving. engagement; and

f) actuator means responsive to force applied through a handle on said device by a device operator for actuating said clutching means wherein said clutching means compresses said sprocket and said intermediate gear together thereby causing said sprocket to rotate and create output which drives said driven element via said flexible power transmission means.

26. The drive system of claim 25 wherein the power transmission means is a belt.

27. The drive system of claim 25 wherein said actuator means comprises an actuator lever having a pair of pins which selectively engage said clutching means, said pins having axes generally paralleling an axis of rotation of said input gear.

28. The drive system of claim 27 wherein said output is dependent upon the extent of movement of the actuator means which in turn is proportional to the force applied through said handle by an operator.

29. An operator controllable power train for transmitting rotative motion from a prime mover to driveable wheels of an appliance, the power train comprising:

a) a driven member coupled to the prime mover for constant rotation about a driven axis when the appliance is in use;

b) a clutch rotatively supported for relative movement from a neutral position toward the driven member and away from the driven member toward the neutral position, the clutch being rotatable about the driven axis when the clutch and driven member frictionally engage one another;

c) an output section operably connected to the clutch and to the wheels for transmitting appliance rotational forces to the wheels when the clutch and driven member are frictionally engaged;

d) a lever operatively connected to the clutch and pivotally mounted for pivoting motion about a pivot axis orthogonal to and spaced from said driven axis;

e) a movably mounted speed control element forming a part of the appliance;

f) a biasing means operatively connected to the clutch for biasing the clutch toward the neutral position; and

g) an operator force-transmitting member operatively connected to and interposed between the element and the lever for transmitting operator supplied speed control forces along a path generally paralleling an imaginary plane including the driven axis for causing relative movement of the clutch against the action of the biasing means.

30. The power means of claim 29 wherein said lever includes a pair of pins operatively connected to the clutch, the pins having axes generally paralleling the driven axis.

31. The power train of claim 29 wherein the lever is a first class lever with the pivot axis interposed between the clutch and force-transmitting member connections to the lever.

32. The power train of claims 29 wherein the pivot axis also is generally parallel to said imaginary plane.

33. The power train of claim 29 wherein there are a pair of counter-rotating driven members, a pair of clutches respectively associated with the driven members and operatively connected to the lever.

34. The power train of claim 29 wherein at least one of said lever operative connections and said pivotal mounting is a spherical connection.

35. A drive system for a self-propelled wheeled appliance having a prime mover comprising:

a) an input gear operatively connected to said prime mover for constant rotation during operation of the appliance;

b) an intermediate gear operatively connected to said input gear also for constant rotation during operation of said appliance;

c) an output gear operatively connected to said intermediate gear;

d) a drive gear operatively connected to said output gear and operatively connected to a wheel shaft of said appliance;

e) clutching means associated with said intermediate gear for clutching said intermediate gear and said output gear; and

f) actuator means spherically connected to said clutching means responsive to operator forces applied through an appliance handle when said appliance is in use for actuating said clutching means.

36. The drive system of claim 35 wherein said actuator means comprises an actuator lever having a pin which engages said clutching means, said pin having an axis generally parallel to an axis of rotation of said input gear.

37. An operator controlled power train for transmitting relative motion from a prime mover to wheels of an appliance, the power train comprising:

a. a driven member coupled to the prime mover for constant rotation about a driven axis when the appliance is in use;

b. a clutch supported for relative movement toward and away from the driven member and for rotation about the driven axis when the clutch and the driven member frictionally engage one another;

c. an output section operably connected to the clutch and to the wheels for transmitting appliance rotational forces to the wheels when the clutch and driven member are frictionally engaged;

d. a lever operatively connected to the clutch and mounted for pivotal motion about a pivot axis orthogonal to and spaced from the driven axis;

e. handle structure including a gripping portion and a movable control element, whereby an operator can steer the appliance and concurrently operate the control element; and

,

f. linkage means interposed between the control member and the lever for transmitting control force from the control member to the lever and thence to the clutch.