US 4,015,909 AGranted

Tamping machine

OwnerShinzo Yamamotoinventor

Life of this patent

Estimating the term…

Loading patent…

Abstract

In the manually guided tamping machine comprising a vertically long casing, a motor mounted thereon, crank means driven thereby, a cylinder snugly mounted to be vertically movable in said casing, a percussion piston in said cylinder, and a pair of coil springs disposed above and below said piston in said cylinder so as to generate vibrating reciprocation to be transmitted to the tamper foot, the invention is characterized by disposing said crank means not at the casing top as usual wherein a relatively long and thin connecting rod or ramrod must pass through the coil spring but vertically amid and in the cylinder, and providing a pair of pistons instead of one in the prior art so as to be subjected to alternate upward and downward movement by means of a pair of connecting rods pivotally linked to said crank means. A shaft for driving said crank means is transversely extended through a vertical slot formed in the cylinder wall and bearings mounted on the casing. Thus it is possible to make construction and assembling work simpler and cost cheaper.

Claims4

Dependent claims

A tamping machine comprising a vertically long casing having a lower end open, a prime mover supported on said casing, a cylinder snugly mounted in said casing so as to be vertically movable therein and having upper and lower ends respectively closed, a foot member fixed to said cylinder at the lower end thereof exposed out of said casing lower end, a pair of pistons each snugly mounted in said cylinder so as to be vertically movable therein as a unit, a pair of coiled springs disposed in said cylinder respectively between the closed upper end thereof and one of said pistons and between the closed lower end of said cylinder and the other piston, a drive shaft having an outer end drive-transmittingly connected with said prime mover via transmission means and transversely extending through bearings mounted at the wall of said casing and a vertically long slot formed in the wall of said cylinder so as to dispose the inner end of said drive shaft between said two pistons, and crank means drive-transmittingly connected with said drive shaft inner end so that rotation output drive of said prime mover may subject the unit of said pistons to vertical reciprocation and consequently said two springs to alternate compression for causing vibrating reciprocation of said foot member.

Dependencies are inferred from the claim text.