Silo unloader leveling apparatus

A leveling structure and control therefor for a top unloading silo unloader including a material collector having an outer end comprising:

• a base adapted to be mounted on the outer end of the collector, a first support movably connected to the base for generally upward and downward movement, a first wheel located adjacent the forward side of the collector, a first mount connecting the first wheel to the first support, a second supply movably connected to the base for generally upward and downward movement, a second wheel located adjacent the trailing side of the collector, a second mount connecting the second wheel to the second support, linear extendible and contractable means operable to pivot the supports and hold the supports in selected positions to maintain the outer end of the collector in a selected operating position, first means connecting the linear extendible and contractable means to the first support, second means connecting the linear extendible and contractable means to the second support, one of said first and second means having lost motion means allowing the linear extendible and contractable means to extend or contract a limited amount without moving the wheels, said lost motion means including a member having first means extended in the linear direction of the movement of the linear extendible and contractable means and second means cooperating with the first means to allow said limited movement of the extendible and contractable means without moving the wheels, control means mounted on the collector for controlling said linear extendible and contractable means, a reference arm adapted to be held in a fixed reference position, means connecting the reference arm to the control means whereby relative movement between the reference arm and control means operates the control means which causes a change in the effective length of the linear extendible and contractable means thereby changing the elevation of the outer end of the collector.

A leveling structure and control therefor for a top unloading silo unloader including a material collector having an outer end comprising:

• a base adapted to be mounted on the outer end of the collector, a first support movably connected to the base for generally up and down movement, a first wheel located adjacent the forward side of the collector, a first mount connecting the first wheel to the first support, a second support movably connected to the base for generally up and down movement, a second wheel located adjacent the trialing side of the collector, a second mount connecting the second wheel to the second support, linear extendible and contractable means operable to pivot the supports and hold the supports in selected positions to maintain the outer end of the collector in a selected operating position, first means connecting the linear extendible and contractable means to the first support, second means connecting the linear extendible and contractable means to the second support, one of said first and second means having lost motion means allowing the linear extendible and contractable means to extend or contract a limited amount without moving the wheels, said lost motion means including a member having an elongated slot, pivot means located in said slot, pivotally connecting the one support to the member, biasing means cooperating with the member and pivot means to urge the wheels into engagement with the material, control means mounted on the collector for controlling said linear extendible and contractable means, a reference arm adapted to be held in a fixed reference position, means connecting the reference arm to the control means whereby relative movement between the reference arm and the control means operates the control means which causes a change in the effective length of the linear extendible and contractable means thereby changing the elevation of the outer end of the collector.

A leveling structure and control therefor for a top unloading silo unloader including a material collector having an outer end comprising:

• a base adapted to be mounted on the outer end of the collector, a first support movably connected to the base for generally upward and downward movement, a first wheel located adjacent the forward side of the collector, a first mount connecting the first wheel to the first support, a second support movably connected to the base for generally upward and downward movement, a second wheel located adjacent the trailing side of the collector, a second mount connecting the second wheel to the second support, linear extendible and contractable means operable to pivot the supports and hold the supports in selected positions to maintain the outer end of the collector in a selected operating position, first means connecting the linear extendible and contractable means to the first support, second means connecting the linear extendible and contractable means to the second support, one of said first and second means having lost motion means allowing the linear extendible and contractable means to extend or contract a limited amount without moving the wheels, said linear extendible and contractable means including a reversible electric motor extendible and contractable means, said lost motion means including a member having an elongated slot, pivot means located in the slot connecting one of said arms to the member, and switch means connected in controlling relationship with said motor means, said switch means having actuator means adapted to operably engage the pivot means on operation of said linear extendible and contractable means and movement of said pivot means to the extended end position in the slot, said control means mounted on the collector.

A top unloading silo unloader for removing material stored in a tower silo having an upright wall and an open doorway comprising:

• first means movable around the silo wall for gathering material, second means moving the gathered material from the first means, said first means having an outer end locatable in a selected operating position, and an up position and a down position relative to the selected operating position, wheel means for supporting the outer end of the first means on the material, third means pendantly supportable in the silo for receiving material from the second means and directing the material to the open doorway, leveling means secured to the first means and wheel means for maintaining the outer end of the first means in the selected operating position, said leveling means including lost motion means operable to maintain the wheel means in engagement with the material, said lost motion means including a member having an elongated slot, means including pivot means located in said slot connecting the wheel means to said member whereby said member can move relative to said wheel means without moving the wheel means up or down, and biasing means cooperating with the member and pivot means to urge the wheel means in engagement with the material, control means mounted on the first means for controlling the leveling means, reference means mounted on the second means, means connecting the reference means to the control means whereby movement of the outer end of the first means to the down position actuates the control means to operate the leveling means to raise the outer end of the first means, and movement of the outer end of the first means to the up position actuates the control means to operate the leveling means to lower the outer end of the first means.