Tilting side-shifting carriage for a lift truck

• US 10,640,349 B2
• Filed: 02/02/2018
• Issued: 05/05/2020
• Est. Priority Date: 02/02/2018
• Status: Active Grant

• Current Assignee: Cascade Corporation (Toyota Motor Corporation)
• Original Assignee: Cascade Corporation (Toyota Motor Corporation)
• Inventors: Prentice, Glenn Steven, McCall, Thomas Joshua
• Primary Examiner(s): Hageman, Mark C
• Application Number:
  US15/887,086
• Publication Number:
  US 20190241417A1
• Time in Patent Office: 823 Days
• CPC Class Codes: B66F 9/07 Floor-to-roof stacking devices, e.g. "stacker cranes", "retrievers"
• CPC Class Codes: B66F 9/146 Side shift, i.e. both forks move together sideways relative to fork support
• CPC Class Codes: B66F 9/16 inclinable relative to mast
• CPC Class Codes: B66F 9/22 Hydraulic devices or systems

Abstract

A carriage for a lift truck arranged to provide for both lateral shifting and tilting of attachments such as forklift forks, in which an outer frame of the carriage is supported by a side-shifter cylinder-and-piston assembly incorporated in an inner frame, and in which the outer frame can be tilted with respect to the inner frame, about a laterally-extending central axis of the side-shifter cylinder-and-piston assembly.

Claims

1. A carriage for a lift truck, comprising:

(a) an inner frame adapted to be mounted on a lift truck mast for vertical movement along the mast;

(b) an outer frame including a pair of spaced-apart opposite side members;

(c) a side-shifter mechanism arranged to move the outer frame laterally with respect to the inner frame;

(d) a tilt mechanism arranged to tilt the outer frame with respect to the inner frame, about a laterally-extending tilt axis;

(e) wherein the side-shifter mechanism includes a transverse structural member of the inner frame that defines a side-shifter hydraulic cylinder having a central axis extending transversely with respect to the carriage and also includes a side-shifter piston rod fitted in the side-shifter hydraulic cylinder and movable transversely with respect to the carriage in the side-shifter hydraulic cylinder;

the side-shifter piston rod having an outer end that is securely and rigidly interconnected with one of the side members of the outer frame, whereby the outer frame can be moved laterally with respect to the inner frame by movement of the side-shifter piston rod within the side-shifter hydraulic cylinder;

(f) wherein the side-shifter hydraulic cylinder includes a bearing located within the side-shifter hydraulic cylinder, the bearing thus being located functionally between the side-shifter hydraulic cylinder and the piston rod and providing radial support for the piston rod, and wherein the outer frame is attached to the inner frame and supported with respect to the inner frame by the side-shifter piston rod being located within the side-shifter hydraulic cylinder and supported by the bearing; and

(g) wherein the central axis of the side-shifter hydraulic cylinder is the tilt axis.

2. The carriage for a lift truck of claim 1 wherein the side-shifter hydraulic cylinder is located between a transversely-extending upper attachment mounting member of the outer frame and a transversely-extending bottom attachment mounting member of the outer frame.

3. The lift truck carriage of claim 1 wherein the transverse structural member that defines a side-shifter hydraulic cylinder defines a pair of coaxially arranged side-shifter hydraulic cylinders and wherein there is a respective side-shifter piston rod disposed in each of the side-shifter hydraulic cylinders and fixedly interconnected with a respective one of the pair of opposite side members of the outer frame.

4. The lift truck carriage of claim 3 including a hydraulic fluid manifold communicating with the side-shifter hydraulic cylinders, the side-shifter hydraulic cylinders being located on opposite sides of the hydraulic fluid manifold and the hydraulic fluid manifold being located centrally between respective opposite side members of the inner frame, and the side-shifter hydraulic cylinders and the manifold being interconnected with the side members as an integral rigid structural member of the inner frame.

5. The lift truck carriage of claim 4 wherein the side-shifter piston rods are movable simultaneously within the respective side-shifter hydraulic cylinders, with one side-shifter piston rod moving toward the hydraulic fluid manifold and the other side-shifter piston rod moving away from the hydraulic fluid manifold, as the side-shifter mechanism moves the outer frame laterally with respect to the inner frame.

6. The lift truck carriage of claim 3 wherein the side-shifter piston rods are movable simultaneously within the respective side-shifter hydraulic cylinders, in the same lateral direction with respect to the rear frame.

7. The lift truck carriage of claim 1 including a carriage tilt cylinder-and-piston assembly mounted on the inner frame and including a piston rod movable with respect to the inner frame and arranged to push a member of the outer frame and thereby to cause the outer frame to tilt with respect to the inner frame, about the central axis of the side-shifter hydraulic cylinder.

8. The lift truck carriage of claim 1 wherein tilting movement of the outer frame with respect to the inner frame results in rotation of the side-shifter piston rod within the side-shifter hydraulic cylinder.

9. The lift truck carriage of claim 1 wherein the carriage is free from load-supporting bearings functionally located between the outer frame and an exterior of the side-shifter hydraulic cylinder.

10. The lift truck carriage of claim 1 wherein the tilt axis operably extends beneath an upper attachment mounting bar supported by the outer frame separately from said side-shifter piston rod.

11. The lift truck carriage of claim 1 wherein the inner frame is free from bearings arranged to support the side-shifter piston rod and located externally of the side-shifter hydraulic cylinder.

12. The lift truck carriage of claim 1 wherein the inner frame is free from bearings located externally of the side-shifter hydraulic cylinder and arranged to act in support of the outer frame other than to tilt the outer frame with respect to the inner frame.