Differential test assembly and method of assembling a differential

{
  "publication_number": "US3875646A",
  "country": "US",
  "kind": "A",
  "title": "Differential test assembly and method of assembling a differential",
  "abstract": "This disclosure is for a jig measuring tool and the method of using the jig measuring tool. The jig measuring tool is of use in aligning gears in a differential, a transmission and final drives in small and large machinery such as small trucks, wheel-type vehicles, crawler vehicles, and industrial material handling machinery and the like. The jig measuring tool makes it possible to save time, save material and to align the gears with greater accuracy in repairing such machinery than with previously available apparatus. Further, it makes it possible for the small repair shops to economically and accurately repair such machinery.",
  "claims": [
    "1. A method for assembling a differential wherein said assembled differential comprises a housing, a pinion gear, pinion gear bearing assemblies, pinion gear depth shims, pinion gear bearing assembly adjusting shims, a ring gear, a differential caseassembly comprising a differential case and differential case bearing assemblies and differential case bearing assembly adjusting shims, said housing having pinion gear bores for positioning said pinion gear bearing assemblies and said housing having differential case bearing bores for positioning said differential case bearing assemblies, said method comprising: a. positioning said differential case in said differential case bearing bores in said housing by means of said differential case in jig measuring tools with said jig measuring tools positioned on said differential case and with said jig measuring tools being substituted for differential case bearing assemblies and said jig measuring tools being in said differential case bearing bores with a first jig measuring tool being positioned in a first differential case bearing bore and a second jig measuring tool being positioned in a second differential case bearing bore; and, b. said differential case not having a ring gear mounted on the ring gear mounting flange; c. adjusting said jig measuring tool to have a correct rotatable clearance between said jig measuring tool on said differential case and said first and second bearing bores so as to eliminate any measurable end play to make possible the checking of said ring gear mounting flange on said differential case for run out.",
    "2. A method according to claim 1 and comprising: a. mounting a ring gear on said ring gear mounting flange on said differential case. b. positioning said differential case in said differential case bearing bores in said housing by means of said differential case in jig measuring tools with said jig measuring tools positioned on said differential case and with said jig measuring tools being substituted for differential case bearing assemblies and said jig measuring tools being in said differential case bearing bores with a first jig measuring tool being positioned in a first differential case bearing bore and a second jig measuring tool being positioned in a second differential case bearing bore; and, c. establishing the correct backlash of the ring gear with respect to the pinion gear by adjusting said first jig measuring tool and said second jig measuring tool to eliminate excess side motion of said differential case in said differential housing while maintaining rotatable clearance between said jig measuring tools and said differential case, and to make possible the checking of the run out of the ring gear.",
    "3. A method according to claim 1 and comprising: a. checking the gear tooth contact between the pinion gear and the ring gear to determine the correct depth of the pinion gear in the housing and with respect to the ring gear; and, b. if necessary, adjusting the depth of the pinion gear in the housing to have correct gear tooth contact between the pinion gear and the ring gear.",
    "4. A method according to claim 3 and comprising: a. removing the jig measuring tools from the differential case test assembly; b. determining the thickness of each jig measuring tool; c. determining the thickness of each differential case bearing assembly; d. determining the thickness of shims on both the off-gear side and the gear side of the differential case to correct for the difference in the thickness dimension between the differential case bearing assembly and the corresponding jig measuring tool; e. said off-gear side being that side of the differential case test assembly away from the differential case mounting flange for the ring gear of the differential case test assembly; f. said gear side being that side of the differential case test assembly adjacent to the differential case mounting flange for the ring gear of the differential case test assembly; g. positioning additional shims on the off-gear side and the gear side of the differential case to properly preload the differential case bearing assemblies; and, h. positioning said differential case bearing assemblies and shims on the differential case.",
    "5. A method according to claim 4 and comprising: a. in determining the difference in the thickness dimension between the differential case bearing assembly and the corresponding jig measuring tool placing the differential case bearing assembly and the jig measuring tool on a flat, even surface; b. placing a flat, even plate on the jig measuring tool and determining a reference thickness for the combination of the jig measuring tool and the flat, even plate; and, c. placing said flat, even plate on the differential case bearing assembly and determining the variation of thickness of the combination of the differential case bearing assembly and the flat, even plate with respect to said reference thickness of the jig measuring tool and the flat, even plate.",
    "6. A method according to claim 4 and comprising: a. in the outboard shim method positioning said shims on the differential case between said differential case bearing assemblies and said differential case bearing bores.",
    "7. A method according to claim 4 and comprising: a. in the inboard shim method positioning said shims on the differential case between said differential case bearing assemblies and the differential case.",
    "8. In a partial differential test assembly a combination comprising a. a housing; b. said housing having first and second differential case bearing bores; c. a differential case; d. said differential case having a first hub and a second hub; e. a first jig measuring tool on the first hub; f. a second jig measuring tool on the second hub; and, g. said first jig measuring tool being in said first bearing bore and said second jig measuring tool being in said second bearing bore to determine the nonpreloaded dimension between the differential case test assembly and said housing.",
    "9. In a combination according to claim 8 and comprising: a. tools on said differential case test assembly and in said first and second bearing bores said tools being adjusted, so as to have a correct rotatable clearance between said jig measuring tools and said first and second bearing bores to make possible the checking of the run out of the differential case ring gear mounting flange.",
    "10. In a combination according to claim 8 and comprising: a. a pinion gear in said housing; b. a ring gear mounted on said differential case test assembly; c. said jig measuring tools on said differential case test assembly said jig measuring tools being adjusted, for positioning the ring gear in correct relationship with the pinion gear to obtain correct backlash between the ring gear and the pinion gear and to make possible the checking of the run out of the ring gear and to make possible the checking of the gear tooth contact between the pinion gear and the ring gear for determining the correct depth of the pinion gear in the housing with respect to the ring gear."
  ],
  "cpc": [
    "F16H 57/021",
    "F16H 2048/385",
    "F16H 2048/405",
    "F16H 2057/0221",
    "F16H 2057/0227",
    "F16H 48/08",
    "F16H 48/40",
    "F16H 55/20",
    "Y10T 29/49771",
    "Y10T 29/4984",
    "Y10T 74/2186"
  ],
  "ipc": [
    "F16H 48/08",
    "F16H 55/20",
    "F16H 57/021"
  ],
  "inventors": [
    "Richard D Pfeiffer"
  ],
  "filing_date": "1974-03-06",
  "publication_date": "1975-04-08",
  "grant_date": "1975-04-08",
  "priority_date": "1971-04-19",
  "application_number": "US-44852674-A",
  "family_id": "26832874",
  "cited_by_count": 12,
  "citations": [
    "US1598599A",
    "US2402142A",
    "US2576377A",
    "US3308546A"
  ]
}