Headed spindle pin for wobble-type sickle drive

• US 5,778,727 A
• Filed: 08/08/1996
• Issued: 07/14/1998
• Est. Priority Date: 08/08/1996
• Status: Expired due to Term

• Current Assignee: Deere & Company, Deutsche Telekom AG
• Original Assignee: Deere & Company
• Inventors: Goodman, Daniel J., Krafka, Jerry Lee, Walters, James C., Richardson, Craig Allen
• Primary Examiner(s): Bonck, Rodney H.
• Assistant Examiner(s): Joyce, William C.
• Application Number:
  US08/693,628
• Time in Patent Office: 705 Days
• Field of Search: 74/60, 56/296, 56/208, 403/79, 403/157, 403/153, 403/150, 403/158
• US Class Current: 74/60
• CPC Class Codes: A01D 34/30 Driving mechanisms for the cutters
• CPC Class Codes: F16H 23/08 connected to reciprocating members by connecting-rods
• CPC Class Codes: Y10T 74/18336 Wabbler type

Abstract

A wobble drive for imparting reciprocating motion to a sickle bar includes a wobble drive shaft rotatable about a first axis and having a cylindrical wobble section formed about an axis making an angle of about 14.5° to the first axis. A toroidal wobble shaft bearing housing is mounted on the wobble section by a set of wobble bearings having their outer races pressed into the bearing housing. An output yoke is coupled to the wobble shaft bearing housing for transmitting the oscillatory motion of the housing, caused by rotation of the drive shaft, to a swing arm fixed to an end of a shaft portion of the yoke. The coupling of the yoke to the wobble bearing housing is accomplished by a pair of headed spindle pins inserted, from the inside out, through pin bores provided at diametrically opposite locations in the wobble shaft bearing housing, and into respective yoke bearings mounted in the ends of a pair of yoke limbs that are joined to the yoke shaft portion. The heads of the spindle pins are respectively received in counterbored sections at the radially inner ends of the pin bores and these counterbores are blocked by outer races of the set of wobble bearings carried by the wobble bearing housing. The pins are each stepped to form first and second sections of different diameters with the radially inner section being larger than the radially outer section and sized for an interference fit with the bearing housing and with the radially outer sections being longer than the pin bores so as to permit the pins to be freely manually inserted through the pin bores and partially into the pin bearings carried by the yoke limbs, whereby the bearing housing and output yoke may be properly aligned one with the other prior to the pins being mechanically pressed into the pin bores.

Claims

1. In a wobble drive including a wobble drive shaft supported for rotating about a first axis and having a cylindrical wobble section formed about a second axis disposed at an angle to said first axis, a toroidal wobble shaft bearing housing mounted to said wobble section by a set of wobble bearings, and an output yoke including a yoke shaft, supported for rotation about a third axis extending perpendicular to said first axis, and joined to a pair of limbs having respective ends disposed against diametrically opposite locations of said wobble shaft bearing housing, each limb end being provided with a bearing bore extending radially relative to said third axis, a pair of pin bores being respectively provided in said bearing housing at said diametrically opposite locations in axial alignment with a respective bearing bore, a yoke bearing being received in each bearing bore, and a spindle pin being received in each yoke bearing and the adjacent pin bore, whereby rotation of said wobble drive shaft will cause oscillation of said wobble shaft bearing housing and, hence, of said yoke, an improved spindle pin connection between said pair of yoke limbs and said wobble shaft bearing housing, comprising:

each spindle pin having an enlarged head at a radially inner end thereof preventing outward migration of said pins from said pin bore and yoke bearing;

each of said pin bores including a counterbored section receiving the enlarged head of a respective one of the spindle pins; and

said set of wobble bearings having outer races located in said bearing housing in respective positions wherein they cooperate to cover said counterbored sections of said pin bores, whereby said spindle pins are prevented from moving axially inwardly in said pin bores.

2. In a wobble drive including a wobble drive shaft supported for rotating about a first axis and having a cylindrical wobble section formed about a second axis disposed at an angle to said first axis, a toroidal wobble shaft bearing housing mounted to said wobble section by a set of wobble bearings, and an output yoke including a yoke shaft, supported for rotation about a third axis extending perpendicular to said first axis, and joined to a pair of limbs having respective ends disposed against diametrically opposite locations of said wobble shaft bearing housing, each limb end being provided with a bearing bore extending radially relative to said third axis, a pair of pin bores being respectively provided in said bearing housing at said diametrically opposite locations in axial alignment with a respective bearing bore, a yoke bearing being received in each bearing bore, and a spindle pin being received in each yoke bearing and the adjacent pin bore, whereby rotation of said wobble drive shaft will cause oscillation of said wobble shaft bearing housing and, hence, of said yoke, an improved spindle pin connection between said pair of yoke limbs and said wobble shaft bearing housing, comprising:

each spindle pin having an enlarged head at a radially inner end thereof preventing outward migration of said pins from said pin bore and yoke bearing;

each of said spindle pins being stepped in diameter at a location between opposite ends of the spindle pin so as to establish a radially inner section having a first diameter and a radially outer section having a second diameter, with said first diameter being sized for establishing an interference fit with a respective pin bore, and with said second diameter being sized smaller than said first diameter for having a close fit with its associated yoke bearing; and

said second section of said spindle pin having a length longer that a length of its associated pin bore, whereby, during assembly of the bearing housing to said yoke prior to installation of said set of wobble bearings, each spindle pin may be manually inserted freely through said associated pin bore and partly into said associated yoke bearing to thus properly align the bearing housing with the output yoke for having the pin mechanically pressed into the associated pin bore.