US 9,541,378 B2Granted

Sash position determining system

AssigneeSiemens Industry, Inc.

InventorsDonald E. Charles, Guy P. Caliendo

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Abstract

A system for determining a sash panel position. An example system includes a linear array of light emitting elements spaced at equal distances from one another mounted on a fume hood frame. The light emitting elements generate a light path towards a sash panel such that the sash panel blocks the light path when positioned at the light emitting element. A linear array of light sensing elements is spaced at equal distances from one another on a side opposite the sash panel. The light sensing elements receive the light path generated by corresponding light emitting elements when the sash panel does not block the light path. The light sensing elements may be on modules having shift registers with bits corresponding to the light sensing elements. The shift register stores a state of the light sensing element and outputs a series of bits indicating the state of each light sensing element.

Claims22

Dependent claims

A system for determining a sash panel position at a sash opening in a fume hood formed by at least one movable sash panel mounted over a hood opening to an enclosure structure of the fume hood, the system comprising:

a light emitting module comprising a linear array of light emitting elements spaced at equal distances from one another, the light emitting module mounted on a fume hood frame with each of the light emitting elements directed to generate a light path normal to a sash panel direction of motion such that the sash panel blocks the light path when positioned at a corresponding one of the light emitting elements;
a light sensing module comprising a linear array of light sensing elements spaced at equal distances from one another, the light sensing module mounted on the fume hood frame on a side opposite the sash panel, the light sensing elements being aligned to each receive the light path generated by a corresponding light emitting element on the light emitting module when the sash panel is not present between the light emitting element and the light sensing element;
and
a shift register in the light sensing module comprising a plurality of bits corresponding to each of the light sensing elements in the linear array, the shift register configured to store a state each light sensing element and to output an output signal comprising a series of bits indicating the state of each light sensing element;
where the series of bits forms a pattern indicating open spaces and closed spaces along the sash panel direction of motion.

2 more elements

A method for determining an area of a sash opening in a fume hood formed by at least one movable sash panel mounted over a hood opening to an enclosure structure of the fume hood, the method comprising:

providing at least one light emitter module mounted on a fume hood frame with a plurality of light emitting elements directed to generate a plurality of light paths directed to corresponding light sensing elements on a light sensing module mounted on the fume hood frame on a side opposite the sash panel;
detecting a state of the light sensing elements;
inputting a stream of bits, each bit indicating an ‘OPEN’ or ‘CLOSED’ state, where each bit corresponds to a specific one of the light sensing elements and the state of each bit corresponds to the state of the light sensing element corresponding to the bit;
using the stream of bits to detect a bit pattern indicative of lengths of open spaces and lengths of closed spaces along a direction of travel of the sash panels;
and
using the bit pattern to calculate lengths of open spaces along the direction of travel, and using the lengths of open spaces to calculate an area of open space.

3 more elements

A fume hood control system configured to control ventilation based on a sash opening area, the system comprising:

a sash position determining system comprising:
a plurality of light emitting elements mounted on a frame member extending along an edge of a sash panel in a sash panel direction of movement, each light emitting element positioned a fixed distance apart, the plurality of light emitting elements mounted to generate a plurality of light paths towards the sash panel when the sash panel is positioned to block the light path;
a plurality of light sensing elements mounted on another frame member extending along another edge of the sash panel, each light sensing element positioned a distance equal to the fixed distance apart, the plurality of light sensing elements mounted on a side opposite the sash panel, each light sensing element positioned to receive a light path of the plurality of light paths from a corresponding one of the light emitting elements when the sash panel is not positioned in the light path;
at least one shift register comprising a plurality of bits corresponding to each of the light sensing elements in the linear array, the shift register configured to store a state of the light sensing element and to serially output an output signal comprising a continuous series of bits indicating the state of each light sensing elements;
and
a sash position determining controller configured to receive the output signal from the shift register and to output the output signal via a communication interface;
and
a fume hood controller configured to receive the output signal from via the communication interface, the fume hood controller configured to determine a sash opening area by:
determining an opening length along a first dimension in the direction of sash panel movement by multiplying the number of bits in the output signal indicative of an opening by the fixed distance between the light sensing elements;
and
multiplying the opening length by an opening length along a second dimension;
and
a ventilation control unit configured to adjust the ventilation in the fume hood according to the sash opening area.

10 more elements

Dependencies are inferred from the claim text.

Facts

Application: 13/832,690Filed 15 Mar 2013
Published: US 2014/0273783 A118 Sep 2014
Granted: 10 Jan 2017
Term ends: Not estimatedThe source records don’t support an estimate.

Classification13 codes

G01B 11/14
Measuring arrangements characterised by the use of optical techniques: for measuring distance or clearance between spaced objects or spaced apertures
G01B 11/002
Measuring arrangements characterised by the use of optical techniques: for measuring two or more coordinates
G01B 11/28
Measuring arrangements characterised by the use of optical techniques: for measuring areas
G01B 11/285
For measuring areas: using photoelectric detection means