Sliding gear for speed-changing transmission

• US 4,619,150 A
• Filed: 08/19/1985
• Issued: 10/28/1986
• Est. Priority Date: 04/02/1980
• Status: Expired due to Fees

• Current Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Wiggenhauser, Pedro
• Primary Examiner(s): Dorner, Kenneth J.
• Assistant Examiner(s): Bednarek, Michael D.
• Application Number:
  US06/767,241
• Time in Patent Office: 435 Days
• Field of Search: 74/332, 74/339, 74/457, 74/458, 74/462, 74/460, 74/410, 72/108, 29/159.2
• US Class Current: 74/332
• CPC Class Codes: F16D 11/14 with clutching members movable only axially F16D11/02, F16D11/08 take precedence
• CPC Class Codes: Y10T 29/49464 Assembling of gear into force transmitting device
• CPC Class Codes: Y10T 74/19237 Internal-external gears
• CPC Class Codes: Y10T 74/19949 Teeth
• CPC Class Codes: Y10T 74/19963 Spur

Abstract

A sliding gear for a speed-changing transmission, idling on an output shaft, has a set of external running teeth in permanent mesh with a driving gear and a set of internal clutch teeth engageable with mating teeth on a coupling member carried by that shaft. The two sets of teeth have centerlines inclined to the axial direction by angles so related as to exert balanced axial forces upon the sliding gear in the engaged position of the latter. The clutch teeth have flanks diverging from their centerlines at small angles, in the direction of the engagement shift, to hold the sliding gear in contact with the coupling member.

Claims

1. In a speed-changing transmission including a driving gear, an output shaft arranged for rotation in a first sense under the action of said driving gear, a sliding gear freely rotatably and axially displaceably mounted on said output shaft and having a set of peripheral running teeth which extend substantially radially outwardly of said sliding gear and are in permanent mesh with said driving gear, said sliding gear being further provided with a set of peripheral first clutch teeth and a coupling member fixedly mounted on said output shaft and having a set of peripheral second clutch teeth adapted to be in meshing engagement with said first clutch teeth upon an axial shift of said sliding gear along said output shaft into an engagement position in which said output shaft is rotated by said driving gear in a second sense opposite to said first sense through the intermediary of said sliding gear and said coupling member;

the improvement comprising said first clutch teeth extend between a pair of axially spaced annular surfaces formed on a sleeve constituting part of said sliding gear and into which said coupling member fits and said first clutch teeth project substantially radially inwardly of said sliding gear, said second clutch teeth extend between a pair of axially spaced faces of a disk forming said coupling member and project substantially radially outwardly of said coupling member, said first clutch teeth being formed within said sleeve, and said running teeth and said first clutch teeth have respective centerlines including with the axial direction of said sliding gear respective acute angles of inclination β

_L and β

_K substantially satisfying the expression

space="preserve" listing-type="equation">β

.sub.K =arctan (r.sub.K /r.sub.L tan β

.sub.L)

where r_K and r_L are the effective radii of said first clutch teeth and said running teeth, respectively, and said acute angles of inclination are of the same sign, whereby axial forces exerted under load upon said running teeth and upon said first clutch teeth in said engagement position of said sliding gear substantially cancel each other under both "push" and "pull" operating conditions in both senses of rotation of said output shaft, each of said first clutch teeth further having its flanks diverging by back angles ρ

<

β

_K of opposite signs from the center line of that first clutch tooth in the direction of said axial shift of said sliding gear into said engagement position of the latter, thereby to maintain said first clutch teeth securely engaged with said second clutch teeth, said flanks including with the centerlines of said clutch teeth back angles of opposite signs ranging between 1.5° and

6°

.

2. A speed-changing transmission as defined in claim 1 wherein said driving gear and said sliding gear are part of a reversing gear train driven by a jack shaft paralleling said output shaft.

3. A speed-changing transmission as defined in claim 1 wherein said driving gear and said sliding gear are part of a reversing gear train driven by a jack shaft paralleling said output shaft.