Safety systems for vertically storing dock levelers

1. A dock leveler safety system for use at a dock platform in a pit having a pit floor, the pit floor being at a lower elevation than the dock platform, the dock platform and the pit floor defining the pit, the dock leveler safety system comprising:

a deck to pivot relative to the dock platform between an upright position and a lowered position, the deck extending farther over the pit floor when the deck is in the lowered position than when the deck is in the upright position; and

a sensor to monitor a sensed region within the pit when the deck is in the upright position, the sensor to provide a reaction signal in response to a body being detected within the sensed region prior to moving the deck toward the lowered position and without the deck having to approach the body, the deck to enter a state of restricted movement in response only to the reaction signal provided by the sensor.

2. The dock leveler safety system of claim 1 , wherein the sensor is to project a beam projected at least partially through the pit.

3. The dock leveler safety system of claim 1 , wherein the sensor comprises a pressure sensitive mat overlying at least a portion of the pit floor.

4. The dock leveler safety system of claim 1 , wherein the sensor comprises an induction loop proximate the pit.

5. The dock leveler safety system of claim 1 , wherein the sensor comprises a motion detector attached to the deck.

6. The dock leveler safety system of claim 1 , wherein the sensor comprises a motion detector mounted to a structure that remains substantially stationary relative to the dock platform as the deck moves between the upright position and the lowered position.

7. The dock leveler safety system of claim 1 , wherein the sensor comprises a body sensor attached to the deck.

8. The dock leveler safety system of claim 1 , further comprising a processor to cause the sensor system to monitor the sensed region prior to receiving an input to move the deck toward the lowered position.

9. The dock leveler safety system of claim 1 , wherein the sensed region remains substantially stationary as the deck moves between the upright position and the lowered position.

10. The dock leveler safety system of claim 1 , wherein an area of the sensed region changes in size as the deck moves between the upright position and the lowered position.

11. The dock leveler safety system of claim 1 , wherein movement of the deck is disabled when the deck is in the state of restricted movement.

12. The dock leveler safety system of claim 1 , wherein downward movement of the deck is disabled when the deck is in the state of restricted movement, and an upward movement of the deck is enabled when the deck is in the state of restricted movement.

13. The dock leveler safety system of claim 1 , wherein the deck enters the state of restricted movement in response to the detection of reaction signal while the deck is in the upright position.

14. The dock leveler safety system of claim 1 , further comprising an alarm to emit an alarm signal in response to the reaction signal.

15. The dock leveler safety system of claim 14 , wherein the alarm signal is audible.

16. The dock leveler safety system of claim 14 , wherein the alarm signal is visual.

17. The dock leveler safety system of claim 1 , wherein the sensed region is not only within the pit when the deck is in the upright position, but the sensed region is also within the pit when the deck is in the lowered position.

18. The dock leveler safety system of claim 1 , wherein the lowered position is within a range of operative positions, the deck to enter the state of restricted movement in response to detection of the reaction signal while a position of the deck is outside of the range of operative positions, and the deck to enter a state of normal operation when a position of the deck is within the operative range.

19. A dock leveler safety system for use at a dock platform in a pit having a pit floor, the pit floor being at a lower elevation than the dock platform, the dock platform and the pit floor defining the pit, the dock leveler safety system comprising:

a deck to pivot relative to the dock platform between an upright position and a lowered position, the deck extending farther over the pit floor when the deck is in the lowered position than when the deck is in the upright position; and

a first sensor and a second sensor to monitor a sensed region within the pit when the deck is in the upright position, the at least one of the first sensor or the second sensor to provide independently a reaction signal in response to a body being detected by the at least one of the first sensor or the second sensor within the sensed region prior to moving the deck toward the lowered position, the deck to enter a state of restricted movement in response only to the reaction signal provided by the at least the first sensor or the sensor signal, wherein each of the first and second sensors comprises a body sensor mounted to a structure that remains substantially stationary relative to the dock platform as the deck moves between the upright position and the lowered position.

20. A dock leveler safety system comprising:

a dock platform;

a pit floor being at a lower elevation than the dock platform, the dock platform and the pit floor defining a pit;

a deck to pivot relative to the dock platform between a stored upright position and a lowered position, the deck extending farther into the pit and over the pit floor when the deck is in the lowered position than when the deck is in the stored upright position; and

a sensor system having a sensed region within the pit when the deck is in the stored upright position, the sensed region covering substantially an entire area of the pit floor, the sensed region being stationary relative to the dock platform as the deck moves between the stored upright position and the lowered position, the sensor system providing a reaction signal in response to a body being detected within the sensed region, the sensor system to detect the body within the sensed region without the deck having to approach the body, the deck being in a state of restricted movement in response to the sensor system providing only the reaction signal indicative of a presence of the body in the sensed region while the deck is in the stored upright position.

21. The dock leveler safety system of claim 20 , wherein the sensor system includes a beam projected at least partially through the pit.

22. A dock leveler safety system comprising:

a dock platform;

a pit floor being at a lower elevation than the dock platform, the dock platform and the pit floor defining a pit;

a deck to pivot relative to the dock platform between a stored upright position and a lowered position, the deck extending farther into the pit when the deck is in the lowered position than when the deck is in the stored upright position, the deck extending farther over the pit floor when the deck is in the lowered position than when the deck is in the stored upright position; and

a sensor system having a sensed region within the pit when the deck is in the stored upright position, an area defining the sensed region decreases as the deck moves from the stored upright position to the lowered position, solely the sensor system providing a reaction signal in response to a body being detected within the sensed region, the sensor system to sense the body without the deck having to approach the body and while the deck is in the upright position, the deck being in a state of restricted movement in response to the sensor system sensing the body in the sensed region and providing the reaction signal while the deck is in the stored upright position and prior to the deck moving toward the lowered position.

23. The dock leveler safety system of claim 22 , wherein the sensor system includes a motion detector attached to the deck.