Box boom loader mechanism

• US 5,984,618 A
• Filed: 03/24/1998
• Issued: 11/16/1999
• Est. Priority Date: 06/30/1997
• Status: Expired due to Term

• Current Assignee: Caterpillar Sarl (Caterpillar Incorporated)
• Original Assignee: Caterpillar Incorporated
• Inventors: Deneve, Jeffrey A., McMillan, Charles T., Loughrin, Owen S.
• Primary Examiner(s): Underwood, Donald W.
• Application Number:
  US09/047,174
• Time in Patent Office: 602 Days
• Field of Search: 414/722, 414/700-715, 414/697, 212/347, 52/111, 52/116, 52/632, 52/731.2, 52/731.6, 52/732.1, 52/735.1, 29/897.2, 29/897.31, 228/165, 228/166, 228/667, 228/174, 228/182
• US Class Current: 414/722
• CPC Class Codes: E02F 3/283 with a single arm pivoted directly on the chassis linkage mechanism for it E02F3/3405
• CPC Class Codes: E02F 3/34 with bucket-arms , i.e. a pair of arms, e.g. manufacturing processes, form, geometry, material of bucket-arms with a single arm E02F3/283 directly pivoted on the frames of tractors or self-propelled machines
• CPC Class Codes: E02F 3/3408 of the parallelogram-type
• CPC Class Codes: E02F 9/0841 Articulated frame, i.e. having at least one pivot point between two travelling gear units tractor-trailer combinations B62D53/00

Abstract

The present invention includes a box boom loader mechanism utilizing a box boom lift arm assembly with a single plate steel top wall and a bottom wall connected with a non-transverse weld to a pair of single plate steel inner side walls to define a rectangular cross section therealong. The connection of the top and bottom walls and the inner side walls defines a bifurcated second end portion straddling a central portion of a frame and being connected therewith. A tilt linkage means is connected to the box boom lift arm assembly and includes a tilt lever, tilt link and tilt cylinder. The connection of the components of the tilt linkage means achieves high visibility and optimal linkage performance. The connection of the bifurcated second end portion to the frame and the non-transverse weld improves strength and fatigue characteristics of the box boom loader mechanism without increasing the weight of the machine.

Claims

1. A box boom loader mechanism for use on a construction machine having a frame with a pair of outer side wall portions, a central portion with a pair of inner side wall portions disposed between the outer side wall portions and spaced a predetermined distance therefrom, comprising:

a box boom lift arm assembly having a pair of inner side walls extending a predetermined length, top and bottom walls extending a predetermined length substantially equal to the predetermined length of the pair of inner side walls and fixedly connected therewith to define a first end portion and a pair of outer side walls connected at a predetermined location along the predetermined length of the pair of inner side walls and extending outwardly therefrom a predetermined length with each outer side wall being fixedly connected to the top and bottom walls to define a bifurcated second end portion opposite the first end portion, the bifurcated second end portion sized to straddle the central portion of the frame and terminating at a frame pin joint pivotally connectable with the frame;

a tilt linkage means pivotally connected to the box boom lift arm assembly;

a lower pin boss fixedly connected to the box boom lift arm assembly at the first end portion and an upper pin boss fixedly connected to the tilt linkage means;

a first hydraulic cylinder pivotally connectable to the frame at a first end and pivotally connected to the tilt linkage means at a second end; and

a second hydraulic cylinder pivotally connectable to the frame at a first end and pivotally connected at a second end to the box boom lift arm assembly at a first pin joint adjacent the bottom wall.

2. The box boom loader mechanism as in claim 1, wherein the frame pin joint includes a pair of frame pin bosses with each frame pin boss fixedly connected to a leg of the bifurcated second end portion and a pair of pins, each of the pair of pins extendable through one of the pair of outer side wall portions of the frame, one of the pair of the frame pin bosses and one of the pair of inner side wall portions of the frame and terminable within the central portion of the frame.

3. The box boom loader mechanism of claim 1, wherein the pair of inner side walls and top wall of the box boom lift arm assembly are fixedly connected through a continuous non-transverse weld extending substantially along the entire predetermined length of the pair of inner side walls, the pair of inner side walls and the bottom wall are fixedly connected through a continuous substantially non-transverse weld extending substantially along the entire predetermined length of the pair of inner side walls and the pair of outer side walls and top and bottom walls are fixedly connected through a continuous non-transverse weld extending substantially along the predetermined length of the outer side walls.

4. The box boom loader mechanism as in claim 1, wherein the tilt linkage means includes a tilt lever pivotally connected to the box boom lift arm assembly at a second pin joint and a tilt link pivotally connected to the tilt lever at a first end with the upper coupler pin boss being fixedly connected to the tilt link at an end opposite the first end.

5. The box boom loader mechanism of claim 4, wherein the tilt lever has a pair of spaced side walls with each one of the pair of spaced side walls being pivotally connected to one of the pair of inner side walls of the box boom lift arm assembly at the second pin joint, the tilt link has a pair of spaced side rails with each one of the pair of side rails being pivotally connected at the first end of the tilt link to one of the pair of side walls of the tilt lever at respective spaced third and fourth pin joints and the upper coupler pin boss extends between the pair of side rails of the tilt link.

6. The box boom loader mechanism of claim 5, wherein the first end of the first and second hydraulic cylinders are connectable at the central portion of the frame, the first and second ends of the first hydraulic cylinder are positioned above the top wall of the box boom lift arm assembly, the second end of the first hydraulic cylinder is positioned below the third and fourth pin joints and therebetween at a fifth pin joint above a central portion of the tilt lever and the first end of the second hydraulic cylinder is positioned below the bottom wall of the box boom lift arm assembly.

7. The box boom loader mechanism of claim 6, wherein the bifurcated second end portion and the first end portion of the box boom lift arm assembly each have a predetermined width greater than a predetermined width of a central portion of the box boom lift arm assembly.

8. The box boom loader mechanism of claim 7, wherein the first end portion diverges outwardly from the central portion on the top and bottom walls to establish the greater width.

9. The box boom loader mechanism of claim 8, including a tool coupler fixedly connected at sixth and seventh pin joints at the respective upper and lower pin bosses for allowing relative movement with the tilt link and the box boom lift arm assembly.

10. The box boom loader mechanism of claim 7, wherein the second end of the second hydraulic cylinder is pivotally connected to the box boom lift arm assembly through a plate assembly substantially located at the central portion of the bottom wall of the boom lift arm assembly, the plate assembly extending a predetermined length along the predetermined length of the bottom wall.

11. The box boom loader mechanism of claim 6, wherein rack and dump stops are positioned at a predetermined location on a top surface of the top wall of the box boom lift arm assembly, the rack and dump stops including an outward projection having a contact surface elevated above the top surface of the top wall.

12. The box boom loader mechanism of claim 11, wherein the tilt lever includes a bar connected to and extending between the pair of side walls at a predetermined position between the second end of the first hydraulic cylinder and the top wall of the box boom lift arm assembly and each of the pair of side rails of the tilt link is angled at a predetermined location and angle.

13. The box boom loader mechanism of claim 12, wherein the bar of the tilt lever contacts the rack stop when the box boom loader mechanism is in a portion of a minimum lift operation range and the bend angle of each of the pair of side rails is adjacent and in a non-contacting relationship with the fifth pin joint and the bar of the tilt lever contacts the dump stop when the box boom loader mechanism is in a portion of a maximum lift operation range.