Unstacker for unstacking items conveyed in a bulk stream

An incline unstacking apparatus comprising:

• a feed conveyor for feeding stacks of items;
• an inclined conveyor arrangement including at least first and second inclined conveyors arranged in series, a first of the inclined conveyors having an upstream end disposed at a discharge end of the feed conveyor, the first inclined conveyor being inclined from its upstream end at an angle relative to a direction of travel of the feed conveyor whereby a stack being discharged from the discharge end tilts forwardly, causing the items in the stack to slide forwardly off one another into a shingle arrangement on the first inclined conveyor, wherein the leading end of an item rests upon the trailing end of a preceding item;
• the second inclined conveyor including an upstream end disposed adjacent a downstream end of the first inclined conveyor and traveling at a faster speed than the first inclined conveyor for at least partially de-shingling the items received from the first inclined conveyor;
• an upstream end of a conveying surface defined by the second inclined conveyor being offset upwardly with respect to a path of travel of a downstream end of a conveying surface defined by the first inclined conveyor, causing a downstream end of each item to descend when passing from the first inclined conveyor to the second inclined conveyor;
• a sensor for sensing items on the first inclined conveyor;
• and
• a controller for regulating a speed of the second inclined conveyor in response to a signal from the sensor, while always maintaining a speed of the second downstream conveyor greater than a speed of the first inclined conveyor.

A decline unstacking apparatus comprising:

• a feed conveyor for feeding stacks of items;
• a declined conveyor arrangement including at least first and second declined conveyors arranged in series, a first of the declined conveyors having an upstream end disposed at a discharge end of the feed conveyor, the first declined conveyor being declined from its upstream end at an angle relative to a direction of travel of the feed conveyor whereby a stack being discharged from the discharge end tilts forwardly, causing the items in the stack to slide forwardly off one another into a shingle arrangement on the first declined conveyor, wherein the leading end of an item is situated beneath the trailing end of a preceding item;
• the second declined conveyor including an upstream end disposed adjacent a downstream end of the first declined conveyor and traveling at a faster speed than the first declined conveyor for at least partially de-shingling the items received from the first declined conveyor;
• an upstream end of a conveying surface defined by the second declined conveyor being offset upwardly with respect to a path of travel of a downstream end of a conveying surface defined by the first declined conveyor, causing a downstream end of each item to be raised when passing from the first declined conveyor to the second declined conveyor;
• a sensor for sensing items on the first declined conveyor;
• and
• a controller for regulating a speed of the second declined conveyor in response to a signal from the sensor, while always maintaining a speed of the second downstream conveyor greater than a speed of the first declined conveyor.

A method of unstacking items fed in stacked relationship in a bulk stream, comprising the steps of:

• A) feeding the stream along a feed conveyor to an upstream end of a declined conveyor arrangement comprising at least first and second declined conveyors arranged in series, whereby a stack of items tilts forwardly as it reaches an upstream end of the first declined conveyor, causing the items to slide forwardly off one another into a shingle arrangement on the first declined conveyor, wherein the leading end of an item is situated beneath the trailing end of a preceding item;
• B) conveying the items continuously downwardly on the first declined conveyor to the second declined conveyor;
• and
• C) driving the second declined conveyor at a faster speed than the first declined conveyor whereby the second declined conveyor at least partially de-shingles the items received from the first declined conveyor.

An unstacking apparatus comprising a decline unstacking section, an incline unstacking section, and a transfer conveyor for transferring items from the decline unstacking section to the incline unstacking section, the decline unstacking section comprising:

• a feed conveyor for feeding stacks of items, and
• a declined conveyor arrangement including at least first and second declined conveyors arranged in series, a first of the declined conveyors having an upstream end disposed at a discharge end of the feed conveyor, the first declined conveyor being declined from its upstream end at an angle relative to a direction of travel of the feed conveyor whereby a stack being discharged from the discharge end tilts forwardly, causing the items in the stack to slide forwardly off one another into a shingle arrangement on the first declined conveyor, wherein the leading end of an item is situated beneath the trailing end of a preceding item;
• the incline unstacking section comprising:
• an inclined conveyor arrangement including at least first and second inclined conveyors arranged in series, a first of the inclined conveyors having an upstream end arranged to receive items that have traveled through the decline unstacking section, the first inclined conveyor being inclined from its upstream end at an angle relative to a direction of travel of the feed conveyor whereby a stack being discharged from the discharge end tilts rearwardly and causes the items in the stack to slide rearwardly off one another into a shingle arrangement on the first inclined conveyor, wherein the leading end of an item rests upon the trailing end of a preceding item, the second inclined conveyor including an upstream end disposed adjacent a downstream end of the first inclined conveyor and traveling at a faster speed than the first inclined conveyor for at least partially de-shingling the items received from the first inclined conveyor.

A method of unstacking items fed in stacked relationship in a bulk stream, comprising the steps of:

• A) feeding the stream along a feed conveyor to an upstream end of a declined conveyor arrangement comprising at least first and second declined conveyors arranged in series, whereby a stack of items tilts forwardly as it reaches an upstream end of the first declined conveyor, causing the items to slide forwardly off one another into a shingle arrangement on the first declined conveyor, wherein the leading end of an item is situated beneath the trailing end of a preceding item;
• B) driving the second declined conveyor at a faster speed than the first declined conveyor whereby the second declined conveyor at least partially de-shingles the items received from the first declined conveyor;
• C) feeding the stream exiting the declined conveyor arrangement to an upstream end of an inclined conveyor arrangement comprising at least first and second inclined conveyors arranged in series, whereby a stack of items tilts forwardly as it reaches an upstream end of the first inclined conveyor, causing the items to slide off one another into a shingle arrangement on the first inclined conveyor, wherein the leading end of an item rests upon the trailing end of a preceding item;
• and
• D) driving the second inclined conveyor at a faster speed than the first inclined conveyor whereby the second inclined conveyor at least partially de-shingles the items received from the first inclined conveyor.

A decline unstacking apparatus comprising:

• a feed conveyor for feeding stacks of items;
• and
• a declined conveyor arrangement including at least first and second declined conveyors arranged in series, a first of the declined conveyors having an upstream end disposed at a discharge end of the feed conveyor, the first declined conveyor being declined from its upstream end at an angle relative to a direction of travel of the feed conveyor whereby a stack being discharged from the discharge end tilts forwardly and causes the items in the stack to slide forwardly off one another into a shingle arrangement on the first declined conveyor, wherein the leading end of an item is situated beneath the trailing end of a preceding item, the second declined conveyor including an upstream end disposed adjacent a downstream end of the first declined conveyor and traveling at a faster speed than the first declined conveyor for at least partially de-shingling the items received from the first declined conveyor;
• wherein an upstream end of a conveying surface defined by the second declined conveyor is offset upwardly with respect to a path of travel of a conveying surface defined by a downstream end of the first declined conveyor, causing a downstream end of each item to be raised when passing from the first declined conveyor to the second declined conveyor, the downstream end of the first declined conveyor and the upstream end of the second declined conveyor traveling around respective first and second support pulleys, the upstream end of the conveying surface defined by the second declined conveyor being offset from the path of travel of the downstream end of the conveying surface defined by the first declined conveyor by a distance equal substantially to a radius of the second support pulley.

A method of unstacking items fed in stacked relationship in a bulk stream, comprising the steps of:

• A) feeding the stream along a feed conveyor to an upstream end of a declined conveyor arrangement comprising at least first and second declined conveyors arranged in series, whereby a stack of items tilts forwardly as it reaches an upstream end of the first declined conveyor, causing the items to slide forwardly off one another into a shingle arrangement on the first declined conveyor, wherein the leading end of an item is situated beneath the trailing end of a preceding item;
• B) driving the second declined conveyor at a faster speed than the first declined conveyor whereby the second declined conveyor at least partially de-shingles the items received from the first declined conveyor;
• C) sensing items at a first location on the first declined conveyor with a first sensor, and regulating a speed of the feed conveyor in response to signals from the first sensor, to prevent the discharge of additional items onto the first declined conveyor until there is sufficient space on the first declined conveyor for receiving additional items;
• and
• D) sensing items on the first declined conveyor with a second sensor at a location spaced downstream of the first sensor, and regulating a speed of the second declined conveyor in accordance with signals from the second sensor while always driving the second declined conveyor faster than the first declined conveyor.

A method of unstacking items fed in stacked relationship in a bulk stream, comprising the steps of:

• A) feeding the stream along a feed conveyor to an upstream end of an inclined conveyor arrangement comprising at least first and second inclined conveyors arranged in series, whereby a stack of items tilts forwardly as it reaches an upstream end of the first inclined conveyor, causing the items to slide forwardly off one another into a shingle arrangement on the first inclined conveyor, wherein the leading end of an item rests upon the trailing end of a preceding item;
• B) driving the second inclined conveyor at a faster speed than the first inclined conveyor whereby the second inclined conveyor at least partially de-shingles the items received from the first inclined conveyor;
• C) sensing items at a first location on the first inclined conveyor with a first sensor, and regulating a speed of the feed conveyor in response to signals from the first sensor, to prevent the discharge of additional items onto the first inclined conveyor until there is sufficient space on the first inclined conveyor for receiving additional items;
• and
• D) sensing items on the first inclined conveyor with a second sensor at a location spaced downstream of the first sensor, and regulating a speed of the second inclined conveyor in accordance with signals from the second sensor while always driving the second inclined conveyor faster than the first inclined conveyor.