Double reduction gear for dispensing gun

A double-reduction drive for a twin-cylinder dispensing gun comprising:

• a housing;
• a dual plunger assembly carried by said housing, said dual plunger assembly further comprising a first plunger shaft and a parallel second plunger shaft both traversing said housing, said first and second plunger shafts each being formed with a toothed rack along their length;
• a trigger connected to said housing at a pivoting axis, said trigger being manually contractible for driving said dual plunger assembly;
• a double-reduction gear assembly carried in said housing for mechanically converting manual contractions of said trigger into incremental axial movement of said dual plunger assembly, said reduction gear assembly further comprising,
• a spur gear connected to said trigger and rotatable therewith about said pivoting axis,
• a main drive gear rotatably carried in said housing, said main drive gear being engagable with said spur gear for driving thereby, and said main drive gear having a larger diameter than said spur gear, and
• a first pinion gear carried in said housing and mounted coaxially with said main drive gear for rotation therewith, said first pinion gear having a smaller diameter than said main driving gear, and said first pinion gear being engagable with said toothed rack of said first plunger shaft, and
• a second pinion gear carried in said housing and mounted coaxially with said main drive gear for rotation therewith, said second pinion gear having a diameter equal to the diameter of said first pinion gear, and said second pinion gear being engagable with said toothed rack of said second plunger shaft;
• whereby contraction of said trigger rotates said spur gear, thereby driving said main drive gear and first and second pinion gears and in turn driving the respective plunger shafts in an equal axial increment.

A quick-release drive for a dispensing gun comprising:

• a housing having opposing side-walls;
• an elongate plunger traversing said housing, said plunger being formed with a toothed rack along a length;
• a trigger pivotally connected to said housing and manually contractible for driving said plunger;
• a gear assembly carried in said housing for mechanically converting manual contractions of said trigger into incremental axial movement of said plunger, said gear assembly further comprising,
• a spur gear connected to said trigger and pivotable therewith,
• a plunger drive assembly including a main drive axle rotatably mounted in said housing, said main drive axle being carried at the ends by notches formed in the opposing side-walls of said housing, said notches being dimensioned to allow a degree of vertical movement of said main drive axle relative to said housing, said plunger drive assembly being selectively engagable with said spur gear and driven thereby when engaged to advance said plunger in axial increments;
• and
• a quick-release assembly means for manually biasing said main drive axle up and down within the notches in the side walls of said housing, thereby allowing selective engagement and disengagement said plunger drive assembly and said spur gear.

A double-reduction drive for a dispensing gun comprising:

• a housing having opposing side-walls;
• an elongate plunger traversing said housing, said plunger being formed with a toothed rack along a length;
• a trigger pivotally connected to said housing and manually contractible for driving said plunger;
• a double-reduction gear assembly carried in said housing for mechanically converting manual contractions of said trigger into incremental axial movement of said plunger, said reduction gear assembly further comprising,
• a spur gear connected to said trigger and pivotable therewith,
• a main drive axle rotatably mounted in said housing, said main drive axle being carried at the ends by notches formed in the opposing side-walls of said housing, said notches being dimensioned to allow a degree of vertical movement of said main drive axle,
• a main drive gear rotatably mounted on said main drive axle in said housing, said main drive gear being selectively engagable with said spur gear and driven thereby when engaged, and said main drive gear having a larger diameter than said spur gear, and
• a pinion gear carried in said housing and mounted coaxially with said main drive gear for rotation therewith, said pinion gear having a smaller diameter than said main driving gear, and said pinion gear being engaged with said toothed rack of said plunger to advance said plunger in axial increments;
• and
• a quick-release assembly means for selectively engaging and disengaging said main drive gear and said spur gear.

A double-reduction drive for a twin-cylinder epoxy dispensing gun comprising:

• a housing;
• a dual plunger assembly by said housing, said dual plunger assembly further comprising a first plunger shaft and a parallel second plunger shaft both traversing said housing, said first and second plunger shafts each being formed with a toothed rack along their length;
• a trigger pivotally connected to said housing and manually contractible for driving said dual plunger assembly;
• a double-reduction gear assembly carried in said housing for mechanically converting manual contractions of said trigger into incremental axial movement of said dual plunger assembly, said reduction gear assembly further comprising,
• a spur gear coupled to said trigger and pivotable therewith,
• a main drive axle rotatably mounted in said housing, said main drive axle being carried at the ends within notches formed in the opposing side-walls of said housing, said notches being dimensioned to allow a degrees of vertical movement of said main drive axle,
• a main drive gear rotatably mounted on said main drive axle in said housing, said main drive gear being selectively engagable with said spur gear and driven thereby when engaged, and said main drive gear having a larger diameter than said spur gear, and
• a first pinion gear carried in said housing and mounted coaxially with said main drive gear for rotation therewith, said first pinion gear having a smaller diameter than said main driving gear, and said first pinion gear being engaged with said toothed rack of said first plunger shaft;
• and
• a second pinion gear carried in said housing and mounted coaxially with said main drive gear for rotation therewith, said second pinion gear having a diameter equal to the diameter of said first pinion gear, and said second pinion gear being engaged with said toothed rack of said second plunger shaft;
• and
• a quick-release assembly means for selectively biasing the main drive axle upward and downward within the notches in the opposing side-walls of said housing, thereby respectively disengaging and engaging said main drive gear from said spur gear and said first and second pinion gears from the respective racks of said first and second plunger shafts;
• whereby contraction of said trigger rotates said spur gear and, when said main drive gear is engaged, drives said main gear and first and second pinion gears in turn driving the respective plunger shafts in an equal axial increment.