A mechanism for maintaining alignment between the gear case or upper portion of a ram type compactor and the spring housing and shoe or lower portion of the compactor which includes a square guide tube and a square hole at the top of the spring housing which reciprocally accepts the guide tube and a segmental wear resistant bearing or bushing forming a lining for the square hole with the bearing being retained in position by the guide tube which extends therethrough and held stationary by the springs in the spring housing. This mechanism enables a person operating a ram type compactor to more effectively handle and maintain proper directional control of the machine.

A compacting device comprises an engine unit, a compacting unit having a tamping plate and a linkage mounting the engine unit on the tamping unit for reciprocatory movement of the tamping unit relative to the engine unit. Power is transmitted between the engine unit and the compacting unit by a transmission that includes an eccentric power output element driven by the engine unit and at least one, and preferably two, springs connected in tension between the compacting unit and the eccentric element of the power output. The linkage by which the engine unit is mounted on the tamping unit comprises two pairs of parallel links, the pairs being laterally spaced-apart and each link being pivotally connected at one end to the compacting unit and at the other end to the engine unit. A portion of a controlling handle is pivotably connected to the two links of each pair at pivot points intermediate the ends thereof, the pivot points being located on the links at points that have substantially no vertical reciprocatory motion in normal operation of the compactor.

A compactor tool for use in conjunction with a mobile prime mover having a vibratory frame to which said tool is mounted. A tool shank is adapted for selective mounting to the vibratory frame and carries a compactor shoe pivotally mounted to the shank lower end, said shoe compacting filled or partially filled conduit burial trenches. Shoes of different widths are readily attachable to said shank for the compacting task at hand. Fluid dispersal means delivers fluid in a metered manner to the shoe when used for compacting paved surfaces.

An eccentric-disk tamper, comprising a vibrator frame intended to be raisably and lowerably attached to a vehicle, also comprises at least one vibrator unit connected to the frame by means of parallel guide linkages and bolts disposed at the pivot points. To avoid wear and tear on the joint bolts and to maintain the damping effect of a rubber insert, the bolts are non-rotatably secured to an inner metal sleeve of a coupling link which further includes an outer metal sleeve and, compressed between these two sleeves, a rubber cylinder non-rotatably fixed to both sleeves. Each such coupling link is non-rotatably connected to a respective guide rod of a parallel linkage. A stop disposed between two such guide rods limits their angle of displacement to displacement within the elastic limit of the rubber.

A pneumatically controlled tamper includes a cylinder which has a lateral supply opening for compressed air and which is integral with a foot. A piston with a symmetrical structure possesses two internal channels provided with check valves. The first channel terminates at one end on the lateral surface of the piston, above its median plane, and at the other end at the bottom of the piston in a lower chamber connected to the atmosphere by an escape opening. The second channel terminates at one end on the lateral surface of the piston, below its median plane, and at the other end at the top of the piston, in an upper chamber connected to the atmosphere through another escape opening. When the piston is on the bottom of the cylinder, the supply opening supplies the first channel, this arrangement making it possible to initiate a reciprocating movement which is maintained without any distribution system. The invention is used preferentially for soil compacting.