Pick-up type drawbar assembly

• US 4,542,913 A
• Filed: 07/26/1984
• Issued: 09/24/1985
• Est. Priority Date: 07/26/1984
• Status: Expired due to Term

• Current Assignee: Deere & Company
• Original Assignee: Deere & Company
• Inventors: Giesmann, Kendall L.
• Primary Examiner(s): Peters, Jr., Joseph F.
• Assistant Examiner(s): Watts, Charles R.
• Application Number:
  US06/634,513
• Time in Patent Office: 425 Days
• Field of Search: 280/415 A, 280/456 R, 280/456 A, 280/461 A, 280/477, 280/478 R, 280/478 A, 280/478 B, 280/479 R, 280/479 A, 280/490 R, 280/490 A, 280/462 , 280/463, 74/104, 74/107
• US Class Current: 172/272
• CPC Class Codes: B60D 1/465 comprising a lifting mechanism, e.g. for coupling while lifting
• CPC Class Codes: Y10T 74/18928 Straight line motions
• CPC Class Codes: Y10T 74/18936 Slidable connections

Abstract

A pick-up type drawbar assembly includes a frame which is fixed to the transmission casing of a tractor. The frame includes a fore-and-aft extending link slot and a curved bellcrank slot. A drawbar link has a rear end which includes an implement engaging hook and a forward end which is pivoted about a pin which slides in the link slot. A bellcrank has one corner pivotally coupled to the drawbar link and another corner pivotally coupled to the frame. A curved slot is located near a third corner of the bellcrank. A pivot pin extends through and is slidable with the curved slots in the frame and the bellcrank. A hydraulic cylinder has a housing pivotally supported in the frame. The rod of the cylinder is coupled to the pivot pin so that extension of the cylinder pivots the bellcrank and lowers the drawbar link. As the link lowers, its forward end and its hook end move rearwardly.

Claims

1. A vehicle hitch assembly for coupling a trailing implement to the vehicle, the hitch assembly comprising:

a support frame fixed to the vehicle and having a fore-and-aft extending link slot and a curved bellcrank slot;

a first pin slidable fore-and-aft in the link slot;

a second pin slidable in the curved bellcrank slot;

a drawbar link having a forward end pivotally coupled to the first pin and having a rearward end including means for engaging the implement;

a bellcrank having a first part coupled to the second pin and having a second part pivotally coupled to a central portion of the drawbar link;

a pivot for pivotally supporting the bellcrank with respect to the frame; and

an actuator means coupled to the bellcrank for extending to pivot and raise the link while the first link end and the first pin move forwardly in the link slot and for retracting to pivot and lower the link while the first link end and the first pin move rearwardly in the link slot.

2. The invention of claim 1, wherein:

the actuator means comprises a hydraulic cylinder with a rod coupled to the second pin.

3. The invention of claim 1, wherein:

the second pin slides upwardly and rearwardly in the curved slot as the actuator means is extended, the second pin sliding downwardly and forwardly in the curved slot as the actuator means is retracted.

5. The invention of claim 1, wherein:

the bellcrank has a curved slot therein, the bellcrank curved slot slidably receiving the second pin.

6. The invention of claim 1, wherein:

the frame curved slot has a radius of curvature centered below and to the rear of the pivot.

4. The invention of 1, wherein:

the second link end moves forwardly as it is raised and rearwardly as it is lowered.

7. In a vehicle hitch assembly having a frame fixed to the vehicle, a drawbar coupled to the frame and an actuator for moving the drawbar with respect to the frame, characterized by:

the frame having a linearly extending drawbar slot and a curved slot;

a first pin slidable in the drawbar slot and pivotally coupled to a forward end of the drawbar;

a second pin slidable in the curved slot and coupled to the actuator; and

a bellcrank having a first part pivotally coupled to the drawbar and a second part coupled to the second pin, the actuator moving to pivot the bellcrank and pivot and raise the drawbar while the forward drawbar end and the first pin move forwardly in the drawbar slot and the actuator moving to pivot the bellcrank, and pivot and lower the drawbar while the forward drawbar end and the first pin move rearwardly in the drawbar slot.

8. The invention of claim 7, further comprising:

a fixed axis pivot for pivotally supporting the bellcrank with respect to the frame, the bellcrank having a curved slot therein which slidably receives the second pin.

9. The invention of claim 7, wherein:

the second pin slides upwardly and rearwardly in the frame curved slot as the drawbar is raised, the second pin sliding downwardly and forwardly in the frame curved slot as the drawbar is lowered.

10. The invention of claim 7, wherein:

an aft end of the drawbar moves forwardly as it is raised and rearwardly as it is lowered.