Tray to hold sheet media for printing

1 . A tray to hold sheet media for printing, the tray comprising:

a movable lift plate to support a stack of media sheets in the tray;

a barrier near a downstream end of the lift plate, the barrier movable between a closed position in which, when the stack of media sheets is on the lift plate, the barrier blocks a downstream end of the stack and an open position in which, when the stack of media sheets is on the lift plate, the barrier does not block a downstream end of at least part of the stack of media sheets, wherein the barrier is a wall positioned between a first sidewall and a second sidewall of the lift plate; and

a rack and pinion actuator connected to the barrier and configured to move the barrier from the closed position to the open position when the lift plate moves toward a pick position.

2 . The tray of claim 1 , comprising a spring urging the barrier toward the closed position.

3 . The tray of claim 1 , wherein the actuator is configured to move the barrier to the open position when the lift plate moves to the pick position.

4 . The tray of claim 3 , wherein the actuator is configured to move the barrier to each of multiple open positions when the lift plate moves to each of multiple pick positions.

5 . The tray of claim 4 , wherein the actuator includes a lever operatively connected to the barrier to move the barrier to the open position when the lever pivots.

6 . The tray of claim 5 , wherein the lever protrudes from the tray to engage a structure next to the tray and pivot when the lift plate moves to the pick position.

7 . The tray of claim 6 , wherein the actuator includes:

a pinion that turns when the lever pivots;

a rack that translates when the pinion turns;

a slot in the rack; and

a pin in the slot, the pin connected to the barrier to rotate the barrier to the open position when the lever turns the pinion and the pinion translates the rack with the slot.

8 . The tray of claim 1 , wherein the barrier extends continuously all the way across the downstream end of the lift plate.

9 . The tray of claim 1 , wherein the barrier includes multiple serrated parts each located near a top of the barrier.

10 . A system for a printer, comprising:

a housing;

a removable tray in the housing to hold sheet media for printing, the tray including a movable lift plate to support a stack of media sheets;

a barrier near one end of the lift plate, the barrier movable between a closed position in which, when the stack of media sheets is supported on the lift plate, the barrier completely blocks a downstream end of the stack and an open position in which, when the stack of media sheets is supported on the lift plate, the barrier does not block the downstream end of at least a top part of the stack of media sheets, wherein the barrier is a wall positioned between a first sidewall and a second sidewall of the lift plate; and

an actuator having a rack coupled to the housing and a pinion on the tray operatively connected to the barrier, the pinion configured to engage the rack and move the barrier to the open position when the lift plate moves toward a pick position.

11 . The system of claim 10 , wherein:

the actuator comprises a ramp next to the tray; and

the actuator comprises a lever protruding from the tray to engage the ramp and pivot when the lift plate moves toward the pick position.

12 . The system of claim 11 , comprising a spring urging the barrier toward the closed position.

13 . A method for a tray that holds a stack of sheet media for printing, the tray including a lift plate movable to and from a pick position, the method comprising:

moving a barrier, positioned near a downstream end of the lift plate, to an unblocked position to unblock at least a top part of the downstream end of the stack of sheet media while simultaneously moving the lift plate to the pick position, wherein the barrier is a wall that extends from a first sidewall to a second sidewall of the lift plate; and

moving the barrier to a blocked position to block the downstream end of the stack of sheet media while simultaneously moving the lift plate away from the pick position.

14 . The method of claim 13 , wherein unblocking at least a top part of the downstream end of the stack of sheet media comprises completely unblocking the downstream end of the stack of sheet media.