Vacuum head magnetic valve construction for pallet loader

Claim 2

In a pallet loader vacuum head of a type having a lift face, having walls forming a plenum chamber, and having an exhauster communicating with the plenum chamber; the combination of one plenum chamber wall being formed with a multiplicity of airflow orifices for communication between the lift face and the plenum chamber; a magnetic valve normally closing each orifice; and each valve including a magnetized metal plate located in the plenum chamber larger than the orifice closed thereby, and an actuator connected to the plate, and extending outward through the orifice, and projecting beyond the lift face, and adapted to contact an article to be lifted when the head is lowered to engage the lift face with such article; whereby contact of the actuator with such article moves the valve plate out of valveclosing position to permit airflow through said orifice to the plenum chamber when the exhauster is operating to provide suction force to lift such article.

Claim 3

The construction defined in claim 1 in which the actuator is formed of nonmetallic material.

Claim 4

The construction defined in claim 1 in which the actuator is formed of plastic material.

Claim 5

The construction defined in claim 1 in which said one plenum chamber wall includes grill means formed with a multiplicity of cells, in which an airflow orifice communicates through each cell with the lift face, and in which the actuator for each valve extends through the corresponding cell.

Claim 6

The construction defined in claim 4 in which each actuator has a depending leg at each end, in which each leg has a foot, and in which shoulder means is formed in each cell engaged by said feet to limit valve opening movement of the actuator.

Claim 7

The construction defined in claim 4 in which each actuator has a depending leg at each end, and in which a central guide vane of greater length than said legs projects downward intermediate of and spaced from said legs.

Claim 8

The construction defined in claim 1 in which said one plenum chamber wall comprises a mask plate and a grill; in which the orifices are formed in the mask plate; in which each orifice comprises a narrow elongated slot; and in which the grill is formed with a plurality of cells, one cell communicating with its corresponding slot.

Claim 9

The construction defined in claim 6 in which each orifice comprises a narrow elongated slot, in which the actuator legs and guide vane have common lateral parallel faces spaced to provide uniform thickness less than the width of the slot through which the actuator extends.

Claim 10

The construction defined in claim 1 in which the magnetic valve plate has a central opening, in which the actuator has a central upwardly projected neck extending through said plate opening, and in which means is provided connecting said neck to said plate.

Claim 11

The construction defined in claim 9 in which means is provided at the ends of each actuator interlocking with the plate to prevent relative movement between the plate and actuator.

Claim 12

Vacuum head construction for a pallet loader including walls forming an exhauster plenum chamber, lift plate means forming one of the plenum chamber walls; the lift plate means including a grill structure and a metal mask plate; the grill structure being formed with a plurality of cells and having a lift face and a back face; the mask plate having a chamber face and an outer face; the grill structure and mask plate being connected with the grill back face adjacent the mask plate outer face; a plurality of elongated airflow slots formed in the mask plate, one slot communicating with each cell; magnetic valve means normally closing each slot including a magnetic plate and a flat actuator connected to the magnetic plate; the magnetic plate being larger than the slot closed thereby and held in contact with the mask plate chamber face by magnetic attraction when in valve-closed position; and the actuator extending through the slot and its corresponding cell and projecting beyond the grill lift face; whereby when the vacuum head is lowered to engage its lift face with articles to be lifted, all projecting actuators contacting such articles are moved incident to such contact and the lowering of the head and move the valves to open position to permit airflow through the cells and valve-opened slots to the plenum chamber providing suction to lift such articles.

Claim 13

Vacuum head construction for a pallet loader including walls forming an exhauster plenum chamber, lift plate means forming one of the plenum chamber walls; the lift plate means including a grill structure and a metal mask plate; the grill structure being formed with a plurality of cells and having a lift face and a back face; the mask plate having a chamber face and an outer face; the grill structure and mask plate being connected with the grill back face adjacent the mask plate outer face; a plurality of elongated airflow slots formed in the mask plate, one slot communicating with each cell; magnetic valve means normally closing each slot including a magnetic plate and a flat actuator connected to the magnetic plate; the magnetic plate being larger than the slot closed thereby and held in contact with the mask plate chamber face by magnetic attraction when in valve-closed position; and the actuator extending through the slot and its corresponding cell and projecting beyond the grill lift face; whereby when the vacuum head is lowered to engage its lift face with articles to be lifted, all projecting actuators contacting such articles are moved incident to such contact and the lowering of the head and move the valves to open position to permit airflow through the cells and valve-opened slots to the plenum chamber providing suction to lift such articles.

Claim 14

The construction defined in claim 11 in which the actuator is formed of plastic material and is smaller in cross section than the elongated slot through which it extends; and in which interengageable stop means are provided on the actuator and cell walls to limit valve opening movement of the actuator.

Claim 15

The construction defined in claim 11 in which each flat actuator has a thickness less than the width of the slot through which it extends for free slidable movement through such slot and to permit airflow around the actuator and through the slot when the valve is in open position.

Claim 16

The construction defined in claim 11 in which the grill structure has walls forming the cells; in which the walls of each cell have a stop shoulder formed therein intermediate the grill lift and back faces; and in which the actuator in each cell has projecting feet engageable with said stop shoulder to limit opening movement of the actuator.

Claim 17

The construction defined in claim 11 in which each actuator has legs at each end extending through its corresponding slot and cell; in which the actuator has a central guide member of greater length than the legs extending through the cell spaced from the legs; and in which the guide member engages an article to be lifted for moving the actuator to open the valve.

Claim 18

The construction defined in claim 11 in which the grill structure has subway-grating-type cellular box-like side and end walls forming the plurality of cells, in which each cell has a thick bottom wall in which a diamond-shaped opening is formed in each bottom wall communicating with the corresponding mask plate slot, and in which the magnetic valve actuator extends through said diamond-shaped opening.

Claim 19

The construction defined in claim 16 in which the cell bottom wall has a shoulder face intermediate the grill lift and back faces extending between the diamond-shaped opening and the cell side and end walls.