Retractable access system ladder and work machine using same

• US 20060070804A1
• Filed: 09/27/2004
• Published: 04/06/2006
• Est. Priority Date: 09/27/2004
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Lapke, Robert A., Scheidenhelm, Kurt J., Beaupre, Eric J.
• Granted Patent: US 7,870,932 B2
• Time in Patent Office: Days
• US Class Current: 182/127
• CPC Class Codes: B60R 3/02 Retractable steps or ladders, e.g. movable under shock B60R3/005 takes precedence
• CPC Class Codes: E02F 9/0833 Improving access, e.g. for maintenance, steps for improving driver's access, handrails
• CPC Class Codes: E06C 5/02 with rigid longitudinal members
• CPC Class Codes: E06C 5/04 capable of being elevated or extended ; Fastening means during transport, e.g. mechanical, hydraulic

Abstract

A work machine and work machine access ladder assembly are provided. The work machine includes a work machine body having an operator platform. A hinge mechanism is coupled to the work machine body and defines a hinge axis oriented diagonally with respect to a vertical line. The ladder may be rotated about the hinge axis between a use and a stowed position.

Claims

1. A work machine comprising:

a work machine body that includes an operator platform;

a hinge mechanism coupled to said work machine body, said hinge mechanism defining a hinge axis oriented diagonally with respect to a vertical line; and

a platform access ladder coupled to said hinge mechanism and movable between a use position and a stowed position about a path restricted by said hinge axis.

2. The work machine of claim 1 wherein said hinge mechanism comprises a modular powered unit having at least one of an hydraulic, pneumatic or electrical actuator.

3. The work machine of claim 2 wherein said hinge mechanism includes first and second hinge portions, said actuator being operable to torque said first and second hinge portions one against the other to move said platform access ladder between said use position and said stowed position.

4. The work machine of claim 3 wherein said actuator is a rotational actuator.

5. The work machine of claim 4 comprising:

a hinge pin coupling said first and second hinge portions and connected to one of the same;

said actuator is mounted to one of said first and second hinge portions and operable to rotate said hinge pin to pivot the respective hinge portion relative to the other of said hinge portions.

6. The work machine of claim 5 wherein said ladder pivots at least about 90°

between said use and said stowed position

7. The work machine of claim 1 comprising:

a ladder cradle mounted on said work machine body;

said cradle including a powered latch system operable to secure said ladder therein, said latch system comprising a movable finger latch engageable about said ladder at said stowed position.

8. The work machine of claim 7 comprising:

a linear actuator operable to move said finger latch between a latched and an unlatched position; and

a biasing member opposing extension of said actuator beyond a selected stroke distance.

9. A work machine access ladder assembly comprising:

a ladder having first and second side rails and a plurality of steps connected between the same;

a hinge mechanism having a first hinge portion mounted to said first side rail and a second hinge portion pivotably coupled to said first hinge portion, said second hinge portion including mounting features for mounting the same to a work machine;

said hinge mechanism defining a hinge axis oriented diagonally with respect to said rails.

10. The ladder assembly of claim 9 wherein said hinge mechanism comprises an actuator operable to torque said first and second hinge portions one against the other.

11. The ladder assembly of claim 10 wherein said actuator is a rotational actuator, said actuator including at least one of an hydraulically, pneumatically or electrically powered actuator.

12. The ladder assembly of claim 10 wherein said actuator is a linear actuator.

13. The ladder assembly of claim 111 wherein:

said actuator is mounted to one of said first and second hinge portions and includes a plurality of gear teeth disposed thereon;

the other of said hinge portions includes a geared member connected therewith and engageable against said actuator; and

said actuator being operable to rotate said geared member to pivot the connected hinge portion relative to the other of said hinge portions.

14. The ladder assembly of claim 13 wherein said geared member comprises a pin coupling said first and second hinge portions together, said pin including a geared collar disposed proximate a center thereof and rotatable within a space defined by at least one of said first and second hinge portions.

16. The method of claim 14 wherein the step of rotating the access ladder comprises:

rotating the ladder with a powered hinge mechanism; and

activating the powered hinge mechanism at a controller positioned within an operator'"'"'s view of a path of the ladder between its use position and stowed position.

15. A method of deploying or stowing an access ladder coupled to a work machine, the method comprising the steps of:

rotating the access ladder about a fixed hinge axis through an angle of at least about 90°

between a use position and a stowed position; and

orienting the hinge axis diagonally with respect to the axis ladder.

17. The method of claim 15 comprising pivoting the ladder with a rotational actuator integral with said powered hinge mechanism.