Hydraulic boom hoist cylinder crane

• US 6,062,405 A
• Filed: 04/25/1997
• Issued: 05/16/2000
• Est. Priority Date: 04/26/1996
• Status: Expired due to Term

• Current Assignee: Manitowoc Cranes LLC (The Manitowoc Company, Inc.)
• Original Assignee: Manitowoc Crane Companies LLC
• Inventors: Pech, David J., Wernecke, Charles R.
• Primary Examiner(s): Brahan, Thomas J.
• Application Number:
  US08/842,974
• Time in Patent Office: 1,117 Days
• Field of Search: 212/175, 212/177, 212/178, 212/298, 212/299, 212/300, 212/138, 212/139, 212/261, 212/262
• US Class Current: 212/298
• CPC Class Codes: B66C 23/36 mounted on road or rail vehicles; Manually-movable jib-cranes for use in workshops; Floating cranes with pneumatic or hydraulic motors B66C23/54; vehicle or ship aspects B60 - B63
• CPC Class Codes: B66C 23/62 Constructional features or details of dredgers E02F
• CPC Class Codes: B66C 23/74 separate from jib
• CPC Class Codes: B66C 23/82 Luffing gear

Abstract

A crane having an upper works rotatably mounted on a lower works, a boom pivotally mounted on the upper works, and a hydraulic boom hoist cylinder to control the angle of the boom. The crane further comprises a mast and a hydraulic cylinder pivotally connected to the upper works. The connection of the mast to the upper works is at a location separate from, and at an elevation below, the elevation of the connection of the hydraulic cylinder to the upper works. The hydraulic cylinder is pivotally connected to the mast and pendently connected to the boom.

Claims

1. A mobile crane having an upper works rotatably mounted on a lower works and a boom pivotally mounted on the upper works comprising:

a) a mast pivotally connected to the upper works at or near the connection of the boom to the upper works;

b) a hydraulic cylinder for controlling the angle of the boom, said hydraulic cylinder being pivotally connected to the upper works;

c) said connection of the mast to the upper works being separate from and at an elevation below the elevation of the connection of the hydraulic cylinder to the upper works;

d) said mast being pivotally connected to said hydraulic cylinder; and

e) said boom being pendently connected to either said mast or said hydraulic cylinder at a location near the connection between the mast and the hydraulic cylinder, wherein said hydraulic cylinder is in tension and said mastisin compression during normal lifting operations of the crane.

2. A crane according to claim 1 wherein said crane further comprises a second hydraulic cylinder, each hydraulic cylinder being pivotally connected between the upper works and the mast.

3. A crane according to claim 1 wherein said mast comprises two struts, each strut being pivotally connected between the upper works and the hydraulic cylinder.

4. A crane according to claim 1 wherein said boom comprises a boom butt, said boom butt being pendently connected to either said mast or said hydraulic cylinder at a location near the connection between the mast and the hydraulic cylinder.

5. A crane according to claim 1 wherein the hydraulic cylinder is extendable or retractable to change the angle of the boom.

6. A crane according to claim 5 wherein the hydraulic cylinder is extendable to lower the top of the boom.

7. A crane according to claim 1 wherein the hydraulic cylinder is extendable to lower the mast to an approximately horizontal position on top of the upper works.

8. A crane according to claim 1 wherein said boom has a first end and a second end, said first end being connected to the upper works, said second end being pendently connected to either said mast or said hydraulic cylinder at a location near the connection between the man and the hydraulic cylinder.

9. A crane according to claim 8 wherein said boom comprises a boom butt and a boom top, said boom top being pendently connected to either said mast or said hydraulic cylinder at a location near the connection between the mast and the hydraulic cylinder.

10. A crane according to claim 9 wherein said boom filer comprises one or more boom inserts connected between said boom top and said boom butt.

11. A crane according to claim 9 wherein said pendent connection between said boom top and said mast or said hydraulic cylinder comprises one or more boom pendants.

12. A crane according to claim 1 wherein said boom comprises a boom top removably connected to a boom butt, further wherein said mast or said hydraulic cylinder is connected to said boom top when said boom top is connected to said boom butt, and said mast or said hydraulic cylinder is connected to said boom butt when said boom top is not connected to said boom butt.

13. A crane according to claim 1 wherein said hydraulic cylinder can be extended to collapse said hydraulic cylinder and said mast on top of the upper works to permit the crane to be disassembled for transport.

14. A mobile crane comprising an upper works having rotating bed, a lower works having a car body and two independently powered crawlers, and a swing bearing rotatably connecting the rotating bed to the car body, the crane further comprising:

a) a boom having a boom top and a boom butt, said boom butt being pivotally connected to the rotating bed of the upper works;

b) a mast having a first end and a second end, said mast first end pivotally connected to the rotating bed of the upper works at or near the connection of the boom butt to the rotating bed, wherein said mast is in compression during normal lifting operations of the crane;

c) a hydraulic cylinder comprising a cylinder bore and a piston rod, said cylinder bore being pivotally connected to the rotating bed of the upper works, wherein said hydraulic cylinder is in tension during normal lifting operations of the crane;

d) said connection of the mast first end to the rotating bed of the upper works being separate from and at an elevation below the elevation of the connection of the cylinder bore to the rotating bed of the upper works;

e) said mast second end being pivotally connected to the piston rod of the hydraulic cylinder;

f) said boom top being pendently connected to either said mast second end or the piston rod of the hydraulic cylinder; and

g) wherein the piston rod of the hydraulic cylinder is extendable to lower said boom top during normal lifting operations of the crane.

15. A crane according to claim 14 wherein said hydraulic cylinder comprises two hydraulic cylinders, each hydraulic cylinder comprising a cylinder bore and a piston rod, each the cylinder bores being pivotally connected to the rotating bed of the upper works and each of the piton rods being pivotally connected to said mast second end.

16. A mobile cue comprising an upper works having rotating bed, a lower works having a car body and two independently powered crawlers, and a swing bearing rotatably connecting the rotating bed to the car body, the crane further comprising:

a) a boom having a boom top, a boom butt, and one or more boor inserts connected between an interior end of the boom butt and an interior end of the boom top, wherein an exterior end of the boom butt is pivotally connected to the rotating bed of the upper works;

b) a mast comprising a frame and having a first end and a second end, said mast first end being pivotally connected to the rotating bed of the upper works at or near the connection of the boom butt to the rotating bed;

c) a pair of hydraulic cylinders, each hydraulic cylinder comprising a cylinder bore and a piston rod, each said cylinder bore being pivotally connected to the rotating bed of the upper works at a location separate from and at an elevation above the elevation of the connection of the mast first end to the rotating bed, each said piston rod being connected to said mast second end;

d) a boom pendant connecting an exterior end of the boom top to said mast second end, said exterior end of the boom top being at an end of the boom opposite the exterior end of the boom butt; and

e) wherein the piston rods of the hydraulic cylinders are extendable to lower said exterior end of said boom top, and further wherein said hydraulic cylinders are in tension and said mast is in compression during normal lifting operations of the crane.

17. A crate according to claim 16 wherein said boom top and said one or more boom inserts have been disconnected from the boom pendant and from the interior end of the boom butt, and her wherein the boom pendant has been reconnected to the interior end of the boom butt in such a manner as to permit said hydraulic cylinders to be extended to lower the interior end of the boom butt.