Gearing assemblies and apparatus

Patent metadata

Field	Value
Publication number	US-11255430-B2
Application number	US-201916963104-A
Country	US
Kind code	B2
Filing date	Jan 16, 2019
Priority date	Jan 19, 2018
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

Some embodiments are directed to a gearing assembly including a rotary input member, a rotary output member and a gearing arrangement between the input member and the output member selectively engageable to effect a driving engagement between the input member and the output member through at least a first torque connection having a first gear ratio and a second torque connection having a second gear ratio. One of the rotary input member and the rotary output member includes a first shaft and the first torque connection includes a first dog clutch including a dog hub having a hub set of teeth and a surrounding dog ring including a ring set of teeth. The hub and ring sets of teeth are radially projecting and mutually engageable. The dog hub is mounted on the first shaft so as to allow axial movement of the dog hub relative to the shaft.

First claim

The invention claimed is:

1. A gearing assembly comprising a rotary input member, a rotary output member and a gearing arrangement between the input member and the output member selectively engageable to effect a driving engagement between the input member and the output member through at least a first torque connection having a first gear ratio and a second torque connection having a second gear ratio,
wherein one of the rotary input member and the rotary output member comprises a first shaft and the first torque connection comprises a first dog clutch comprising a dog hub comprising a hub set of teeth and a surrounding dog ring comprising a ring set of teeth, the hub and ring sets of teeth being radially projecting and mutually engageable,
the dog hub being mounted on the first shaft so as to allow axial movement of the dog hub relative to the first shaft and dog ring with rotation of the dog hub relative to the first shaft being resisted such that when the dog hub is axially aligned with the dog ring, the hub and ring sets of teeth engage and rotational drive may be transferred between the first shaft and the dog ring,
the hub and ring sets of teeth of the first dog clutch being dimensioned and spaced so that upon axial movement between the dog hub and the dog ring with the sets of teeth appropriately in register with one another, the teeth in each set may pass through spacings between the teeth in the respective other set, so that the dog hub is moveable between a first disengaged position with the hub set of teeth axially spaced in a first direction from the ring set of teeth, a first engaged position with the hub set of teeth aligned and engaged with the ring set of teeth, and a second disengaged position with the hub set of teeth axially spaced in a second direction from the ring set of teeth, and
wherein the gearing arrangement comprises a first planetary gear stage having a sun gear which comprises the dog ring of the first dog clutch.

2. The gearing assembly according to claim 1 , wherein the second torque connection comprises a second dog clutch comprising a respective dog hub comprising a respective hub set of teeth and a respective surrounding dog ring comprising a respective ring set of teeth, the respective hub and ring sets of teeth being radially projecting and mutually engageable, the gearing arrangement comprising a second planetary gear stage having a sun gear which comprises the dog ring of the second dog clutch and wherein the dog ring of the second dog clutch comprises a planetary gear carrier of the first planetary gear stage.

3. The gearing assembly according to claim 2 , wherein the first and second dog clutches share a common dog hub, which is moveable between the first engaged position in which driving engagement between the input member and the output member is effected through the first torque connection and a second engaged position in which driving engagement between the input member and the output member is effected through the second torque connection.

4. The gearing assembly according to claim 3 , wherein the dog hub has a common hub set of teeth for selective engagement with the ring set of teeth of the first dog clutch and a ring set of teeth of the second dog clutch.

5. The gearing assembly according to claim 3 , wherein the dog hub comprises a first hub set of teeth for selective engagement with the ring set of teeth of the first dog clutch and a second hub set of teeth for selective engagement with a ring set of teeth of a second dog clutch.

6. The gearing assembly according to claim 1 , wherein the gearing assembly comprises a gearing arrangement between the input member and the output member selectively engageable to effect a driving engagement between the input member and the output member through at least a first torque connection having a first gear ratio, a second torque connection having a second gear ratio, and a third torque connection having a third gear ratio, wherein the first torque connection comprises a first dog clutch, the second torque connection comprises a second dog clutch, and the third torque connection comprises a third dog clutch.

7. The gearing assembly according to claim 6 , wherein the first, second, and third dog clutches comprise a common dog hub which is arranged for movement axially between the first engaged position in which driving engagement between the input member and the output member is effected through the first torque connection, a second engaged position in which driving engagement between the input member and the output member is effected through the second torque connection, and a third engaged position in which driving engagement between the input member and the output member is effected through the third torque connection, wherein the first engaged position is axially between the second engaged position and the third engaged position.

8. The gearing according to claim 7 , wherein the common dog hub comprises a common set of hub teeth which is for selective engagement with the dog ring of the first dog clutch and respective dog rings of the second dog clutch and the third dog clutch.

9. The gearing assembly according to claim 7 , wherein the second and/or third dog clutch are of a different kind than the first dog clutch and the common dog hub comprises two or more hub sets of teeth each for engaging with a corresponding remaining portion of at least one of the first, second, and third dog clutch.

10. The gearing assembly according to claim 1 , wherein the hub set of teeth and the ring set of teeth are profiled to encourage ease of engagement whilst discouraging dis-engagement when under rotational driving load.

11. The gearing assembly according to claim 1 , wherein the teeth of the hub set of teeth and/or the ring set of teeth comprise radiused contact surfaces to encourage engagement.

12. The gearing assembly according to claim 1 , wherein engaging surfaces of teeth of the hub set of teeth and the ring set of teeth comprise complementary convex and concave surface portions such that when the sets of teeth are aligned, the convex portions on one set of teeth tend to rest in the concave portions of the other set of teeth so as to resist relative axial movement between the sets of teeth when under rotational load.

13. A gearing apparatus comprising the gearing assembly according to claim 1 and a shift arrangement for shifting the gearing arrangement between a first state in which there is driving engagement between the input member and the output member through the first torque connection and a second state in which the gearing arrangement does not provide driving engagement between the input member and the output member through the first torque connection.

14. The gearing apparatus according to claim 13 , wherein the shift arrangement comprises at least one shift stick for acting on the gearing assembly for shifting the gearing arrangement between at least the first state and the second state and the at least one shift stick is carried in a slot extending axially in the outer surface of the first shaft and arranged for axial movement therewithin relative to the first shaft for acting on the gearing assembly in shifting the gearing arrangement between the first state and the second state.

15. A gearing apparatus comprising a gearing assembly comprising a rotary input member, a rotary output member and a gearing arrangement between the input member and the output member selectively engageable to effect a driving engagement between the input member and the output member through at least a first torque connection having a first gear ratio and a second torqu

Assignees

• Qinetiq Ltd

Inventors

• Thompson Robert William
• Flaxman Robert John Bonner

Classifications

• F16H63/30 Primary

  Constructional features of the final output mechanisms · CPC title

• F16H2063/3093

  Final output elements, i.e. the final elements to establish gear ratio, e.g. coupling sleeves or other means establishing coupling to shaft · CPC title

• B60K17/08

  of mechanical type · CPC title

• F16H2200/2007

  with two sets of orbital gears · CPC title

• B60K17/02

  characterised by arrangement, location, or kind of clutch · CPC title