Ejector system for color sorter

An ejector system for a color sorter, eliminates particulate matter by air by detection of the particulate matter falling from an end of a transfer device at a predetermined position, and has a nozzle part in which a plurality of air flow paths that communicate with a plurality of nozzle holes are formed. A manifold part is provided with a plurality of electromagnetic valves that communicate with an air space communicating with a compressed air source and in which a plurality of air flow paths for supplying compressed air to the corresponding air flow paths in the nozzle part by the operation of the respective electromagnetic valves are formed. The nozzle part and the manifold part are separably integrated while open surfaces of the air flow paths in the nozzle part and open surfaces of the air flow paths in the manifold part are brought into contact with each other.

TECHNICAL FIELD

The present invention relates to an ejector system employed in a color sorter for sorting acceptable items and unacceptable items from among rice, wheat, or other grains; resin pellets; coffee beans; or other such particulate matter; or for eliminating foreign matter admixed into particulate matter.

BACKGROUND ART

Color sorters that sort acceptable items and unacceptable items in particulate matter, or that eliminate foreign matter admixed into particulate matter, are widely known in the prior art.

In a color sorter, particulate matter that is launched into the air, for example, from the edge of a chute or belt, is irradiated with light, whereupon the reflected light or transmitted light from the particulate matter is detected by sensors. The detection signal is compared with a reference value to identify unacceptable items or foreign matter, whereupon the unacceptable items or foreign matter are eliminated by being carried away with jets of air from ejector nozzles or the like, thereby sorting the particulate matter (see Patent Documents 1 and 2, for example).

FIG. 13shows the ejector nozzle of the sorter disclosed in Patent Document 1. The ejector nozzle101has a plurality of slit-like air jet holes102and a plurality of holes103communicating with the air jet holes102, with hoses104that connect to a jet air supply, not shown, fitted into each of the plurality of holes103to jet air from the air jet holes102.

However, a problem with the ejector nozzle101in question is that difficulties arise when the hoses104dislodge from the holes103. Moreover, dust and dirt tends to collect in the ejector nozzle101, including the hoses104, making frequent cleaning and maintenance necessary.

FIG. 14shows an air jetting device of the sorter disclosed in Patent Document 2. In the air jetting device111in question, a plurality of nozzle blocks112, a plurality of electromagnetic valves113connected in duct-wise fashion to the plurality of nozzle blocks112, and a single receiver tank114connected in duct-wise fashion plurality of electromagnetic valves113are arranged on a base115. In the air jetting device111in question, compressed air held in the receiver tank114is supplied through ducts to the electromagnetic valves113, and when a specific electromagnetic valve113is opened, air is supplied through a duct to the corresponding nozzle block112, whereupon air is jetted from a nozzle116formed at the tip of the nozzle block112.

In the air jetting device111, the nozzle blocks112and the electromagnetic valves113are respectively connected by ducts, so there is no problem of difficulties arising when the hoses104dislodge from the holes103, as in the aforedescribed ejector nozzle101.

However, in the air jetting device111, the plurality of nozzle blocks112, the plurality of electromagnetic valves113, and the receiver tank114are respectively connected by ducts and arranged on the base115, making cleaning and maintenance elaborate.

CITATION LIST

Patent Literature

Patent Document 1: Japanese Laid-Open Patent Application 8-252535

Patent Document 2: Japanese Laid-Open Patent Application 5-169037

SUMMARY OF INVENTION

Technical Problem

An object of the present invention is to offer an ejector system for a color sorter, having excellent cleaning and maintenance performance.

Solution to Problem

In order to attain the aforedescribed object, the present invention is an ejector system for a color sorter in which particulate matter falling from the end of a transfer means is detected at a predetermined position, and based on the result of the detection, the particulate matter is eliminated by air, characterized by being constituted from: a nozzle part in which a plurality of nozzle holes open at the front end, and in which are formed a plurality of air flow paths that communicate with the nozzle holes; and a manifold part in which is formed an air space communicating with a compressed air source, the manifold part being provided with a plurality of electromagnetic valves communicating with the air space, and in which are formed a plurality of air flow paths for supplying compressed air to corresponding air flow paths of the nozzle part by operation of the electromagnetic valves, the nozzle part and the manifold part being separably integrated in a state in which the open surfaces of the air flow paths in the nozzle part and the open surfaces of the air flow paths in the manifold part are brought in contact with each other.

In the present invention, in preferred practice, the open surfaces of the air flow paths in the nozzle part and the open surfaces of the air flow paths in the manifold part are fitted together as projections and recesses, and the nozzle part and the manifold part are separably integrated by a pair of rods extending from the manifold part being inserted into a pair of through-holes formed in the nozzle part.

In the present invention, in preferred practice, the nozzle part is constituted by screwing together a nozzle upper member and a nozzle lower member, the manifold part is constituted by screwing together a manifold upper member and a manifold lower member, and the air flow paths are formed on opposed surfaces of the respective upper and lower members.

In the present invention, in preferred practice, the arrangement with respect to the color sorter is such that the nozzle part is positioned on the flow path of the particulate matter, and the manifold part is positioned in the interior of the sorter body.

In the present invention, in preferred practice, at one side end of the upper surface of the nozzle part, there is arranged an air sweeper provided with nozzles opening towards the other side end of the upper surface of the nozzle part; in the nozzle part, there are formed air flow paths that communicate with the nozzles of the air sweeper; and in the manifold part, there are arranged electromagnetic valves that communicate with the air space, and there are formed air flow paths that, by operation of the electromagnetic valves, supply compressed air to air flow paths communicating with the nozzles of the air sweeper formed in the nozzle part.

In the present invention, in preferred practice, the plurality of electromagnetic valves are arranged in a plurality of rows, in a phase-shifted state with respect to the manifold part.

Advantageous Effects of Invention

According to the ejector system for a color sorter in the present invention, the nozzle part and the manifold part are separably integrated in a state in which the open surfaces of the air flow paths in the nozzle part and the open surfaces of the air flow paths in the manifold part are brought in contact with each other, whereby the difficulties with hose dislodgment encountered in the prior art do not arise, and cleaning and maintenance performance are excellent.

In the ejector system of the present invention, when the open surfaces of the air flow paths in the nozzle part and the open surfaces of the air flow paths in the manifold part are fitted together as projections and recesses, and a pair of rods extending from the manifold part are inserted into a pair of through-holes formed in the nozzle part, the nozzle part and the manifold part can be separated easily, improving the cleaning and maintenance performance.

In the ejector system of the present invention, when the nozzle part is constituted by screwing together a nozzle upper member and a nozzle lower member, the manifold part is constituted by screwing together a manifold upper member and a manifold lower member, and the air flow paths are formed on opposed surfaces of the respective upper and lower members, the upper and lower members of the nozzle part and of the manifold part can be separated easily, and the air flow paths can be cleaned easily.

When the ejector system of the present invention is arranged with respect to the color sorter such that the manifold part is positioned in the interior of the sorter body, the electromagnetic valves do not become soiled by dust and the like stirred up within the flow path in association with falling of the particulate matter, and the burden of cleaning and maintenance is reduced.

In the ejector system of the present invention, when one side end of the upper surface of the nozzle part has arranged thereon an air sweeper provided with nozzles opening towards the other side end of the upper surface of the nozzle part, starting material or dust and the like accumulating on the upper surface of the nozzle part can be automatically cleaned away, reducing the burden of cleaning and maintenance by workers.

In the ejector system of the present invention, when the plurality of electromagnetic valves are arranged in a plurality of rows in a phase-shifted state with respect to the manifold part, the number of nozzle holes can be increased, as compared to a case in which the electromagnetic valves are arranged in a single row.

DESCRIPTION OF EMBODIMENTS

The following description of the embodiments of the present invention makes reference to the drawings.

<Overview of Color Sorter>

An overview of the color sorter is now described.

FIG. 1is an example of a color sorter, showing an exterior perspective view thereof.FIG. 2shows a simplified side sectional view of the color sorter shown inFIG. 1.

The color sorter1in question is provided with a loading hopper2for loading particulate matter; a bucket conveyor3for lifting the particulate matter up into the top part of the sorter1; a storage tank4for storing the lifted particulate matter; a rotary valve5arranged in the outlet of the storage tank4; a sloping chute6having predetermined width, arranged below the rotary valve5; a pair of optical detection devices7a,7barranged to the front and back with the sloping chute6therebetween; an ejector system8arranged below the optical detection devices7a,7b; and a particulate matter discharge trough9arranged below the ejector system8.

The optical detection devices7a,7bare provided with sensors10a,10b, mirrors11a,11b, illumination means12a,12b, and background means13a,13b.

As the sensors10a,10b, there are employed CCD line sensors or the like, constituted by a plurality of photodetector elements concatenated in a line pattern and assigned to a position in the width direction of the sloping chute6, for example.

The background means13a,13bare arranged to the back of a particulate matter detection position O on the optical axes of the sensors10a,10b.

The optical detection devices7a,7bare adapted to detect particulate matter falling from the bottom edge of the sloping chute6, at positions in the width direction of the falling trajectory thereof.

The ejector system8is also provided with a nozzle part20having a plurality of nozzle holes assigned to positions in the width direction of the sloping chute6. Based on the results detected by the optical detection devices7a,7b, particulate matter falling from the bottom edge of the sloping chute6is carried away by jets of air from nozzle holes at corresponding positions in the width direction of the falling trajectory thereof.

The particulate matter discharge trough9is provided with a satisfactory item discharge trough9aarranged along the falling trajectory of the particulate matter from the bottom edge of the sloping chute6, and with an unsatisfactory item discharge trough9barranged at a position allowing the falling trajectory of the particulate matter to be modified by a jet of air from a nozzle hole of the nozzle part20constituting the ejector system8.

In the color sorter1, particulate matter loaded into the loading hopper2is lifted by the bucket conveyor3and stored in the storage tank4. The particulate matter, which is supplied from the storage tank4at a constant flow rate via the rotary valve5, spreads out across the width direction of the sloping chute6, and flows down naturally in a continuous manner. Falling particulate matter having been launched into the air from the bottom edge of the sloping chute6is illuminated by the illumination means12a,12bof the pair of optical detection devices7a,7b, and with the background means13a,13bas the background, is imaged by the sensors10a,10bat a particulate matter detection position O extending linearly in the width direction of the sloping chute6, whereby unsatisfactory items or foreign matter are identified by comparing the voltage value of the image signal to a reference threshold value, or the like. Particulate matter identified as being satisfactory items then falls into the satisfactory item trough9aarranged along a predetermined falling trajectory. Particulate matter identified as being unsatisfactory items or foreign matter is carried away by air jetted at predetermined timing from a nozzle hole that opens onto a predetermined position of the nozzle part20constituting the ejector system8, and falls into the unsatisfactory item trough9b.

Alternatively, satisfactory items, instead of unsatisfactory items or foreign matter, may be the particulate matter that is carried away by air in this way.

The ejector system of the present invention is now described.

FIG. 3is a perspective view of an ejector system in an embodiment of the present invention.

FIG. 4is a fragmentary enlarged front view of the ejector system shown inFIG. 3.

As shown inFIG. 3, the ejector system8in the present embodiment is constituted by a nozzle part20and a manifold part30.

The nozzle part20is constituted by screwing together a nozzle upper member20aand a nozzle lower member20b. The manifold part30is constituted by screwing together a manifold upper member30aand a manifold lower member30b.

Here, as will be clear fromFIG. 4, a plurality of nozzle holes21open along the width direction at the front surface of the nozzle part20. Moreover, as shown inFIGS. 3 and 4, at one side end of the upper surface of the nozzle part20, there is arranged an air sweeper23provided with nozzles22that open towards the other side end of the upper surface thereof.

An attachment member31for attaching the ejector system8to the color sorter is screwed to the front of the upper face of the manifold upper member30a.

FIG. 5shows a view of the ejector system shown inFIG. 3, with the nozzle part and the manifold part exploded.FIG. 6is a perspective view of the exploded manifold part.

As shown inFIG. 5, a laterally elongated recess part32is formed on the front surface of the manifold part30, and a pair of rods33a,33bare formed at either side of the recess part32.

Meanwhile, a laterally-elongated projection part24is formed on the back surface of the nozzle part20, and a pair of through-holes25a,25bare formed at either side of the projection part24.

Here, as will be clear fromFIG. 6, a plurality of air flow paths37communicating with the nozzle holes21open along the width direction into the recess part32formed on the front surface of the manifold part30. Attachment holes34a,34bfor the pair of rods33a,33bare formed at either side of the recess part32.

As shown inFIGS. 4 and 6, a plurality of electromagnetic valves35a,35bare arranged, in correspondence with the air flow paths37that open into the recess part32, along the width direction on the back face of the manifold upper member30aand of the manifold lower member30b. A pair of air line connection parts36a,36bfor connecting compressed air supply lines are arranged on the lower surface of the manifold lower member30b.

Here, as will be clear fromFIG. 4, the electromagnetic valves35a,35bare arranged in a phase-shifted state in the width direction, with respect to the manifold upper and lower members30a,30b.

As the electromagnetic valves35a,35bthere may be employed any of the widely known types, and therefore a description is omitted here.

In the ejector system8of the present embodiment, the nozzle part20and the manifold part30are integrated by inserting the pair of rods33a,33battached to the manifold part30into the pair of through-holes25a,25bformed in the nozzle part20; and in a state in which the projection part24formed on the back surface of the nozzle part20has been mated into the recess part32formed on the front surface of the manifold part30, female thread parts of fastening members26a,26bshown inFIG. 5are threaded and tightened onto distal end male thread parts of the rods33a,33bthat project out through the through-holes25a,25b.

In the ejector system of the present embodiment, because the nozzle part20and the manifold part30are integrated through tightening of the fastening members26a,26b, the nozzle part20and the manifold part30can be easily separated, for improved cleaning and maintenance performance.

Next,FIG. 7shows a plan view, in the detached state, of the nozzle upper member and the manifold upper member of the ejector system shown inFIG. 3.FIG. 8shows a bottom view of the nozzle upper member and the manifold upper member in the detached state inFIG. 7.

As shown inFIG. 7, a plurality of slots37b,27bcontinuing in the width direction from the front of the manifold lower member30bto the front end of the nozzle lower member20bare formed on the upper surfaces of the nozzle and manifold lower members20b,30b.

At the back of the upper face of the manifold lower member30b, there is formed an air space recess part40bthat opens onto the lower surface through air supply holes39a,39b. A plurality of communicating holes38bare formed across the width direction of the manifold lower member30b.

The air space recess part40bcommunicates with the plurality of electromagnetic valves35bthat have been arranged on the back surface of the manifold lower member30b. The communicating holes38bcommunicate at the back end with the electromagnetic valves35b, and communicate alternately at the front end with the slots37bformed at the front of the manifold lower member30b.

As shown inFIG. 8, a plurality of slots37a,27acontinuing in the width direction from the front of the manifold upper member30ato the front end of the nozzle upper member20aare formed on the lower surfaces of the nozzle and manifold upper members20a,30a.

At the back of the lower face of the manifold upper member30a, there is formed an air space recess part40a. A plurality of communicating holes38aare formed across the width direction of the manifold upper member30a.

The air space recess part40acommunicates with the plurality of electromagnetic valves35athat have been arranged on the back surface of the manifold upper member30a. The communicating holes38acommunicate at the back end with the electromagnetic valves35a, and communicate alternately at the front end with the slots37aformed at the front of the manifold upper member30a.

In the ejector system of the present embodiment, a plurality of independent air passages27,37affording communication between the nozzle holes21and the communicating holes38a,38bare constituted by the slots27b,37bformed on the upper surfaces of the nozzle and manifold lower members20b,30bshown inFIG. 7, and the slots27a,37aformed on the lower surfaces of the nozzle and manifold upper members20a,30ashown inFIG. 8.

At this time, the slots37bthat communicate with the communicating holes38bformed in the manifold lower member30bconstitute air passages to the slots37athat do not communicate with the communicating holes38aformed in the manifold upper member30a. The slots37bthat do not communicate with the communicating holes38bformed in the manifold lower member30bconstitute air passages to the slots37athat communicate with the communicating holes38aformed in the manifold upper member30a.

A communicating hole29communicating with the upper surface of the nozzle upper member20ais formed in the slot28athat has been formed at the left end of the lower surface of the nozzle upper member20ashown inFIG. 8. The slot28ain question constitutes an air passage28communicating with the slot28bthat has been formed at the left end of the upper surface of the nozzle lower member20bshown inFIG. 7, as well as with the nozzles22of the air sweeper23arranged on the upper surface of the nozzle part20

In the ejector system of the present embodiment, an air space40, discussed below, is constituted by the air space recess part40bformed in the upper surface of the manifold lower member30bshown inFIG. 7, and the air space recess part40aformed in the lower surface of the manifold upper member30ashown inFIG. 8. The air space40is a space for storing compressed air supplied from a compressed air source, not shown, to the air supply holes39a,39bthat open onto the lower surface of the manifold lower member30b.

FIG. 9shows an air flow path inside the nozzle part and the manifold part, taken along section A-A inFIG. 3.FIG. 10shows an air flow path inside the nozzle part and the manifold part, taken along section B-B inFIG. 3.

The air flow path shown inFIG. 9, via the electromagnetic valve35barranged in the manifold lower member30b, affords communication between the air space40formed in the manifold part30and the communicating hole38bformed in the lower member30b; and via the air flow path37formed at the front of the manifold part30and the air flow path27formed in the nozzle part20, affords communication with the nozzle hole21that opens onto the front surface of the nozzle part20.

The air flow path shown inFIG. 10, via the electromagnetic valve35aarranged in the manifold upper member30a, affords communication between the air space40formed in the manifold part30and the communicating hole38aformed in the upper member30a; and via the air flow path37formed at the front of the manifold part30and the air flow path27formed in the nozzle part20, affords communication with the nozzle hole21that opens onto the front surface of the nozzle part20.

The air flow paths shown inFIGS. 9 and 10supply air from the air space40to the nozzle holes21through opening of the electromagnetic valves35a,35b.

For example, in the color sorter1shown inFIGS. 1 and 2, in a case in which an unsatisfactory item is detected by the optical detection devices7a,7b, and a position in the width direction of the falling trajectory of the particulate matter detected to be an unsatisfactory item corresponds to the position of the nozzle holes21shown inFIG. 9or10, the ejector system8of the present embodiment will open the electromagnetic valve35a,35bshown inFIG. 9or10, and thereby jet high pressure air stored in the air space40, from either of the aforedescribed nozzle holes21over the predetermined air flow path.

FIG. 11shows an air flow path inside the nozzle part and the manifold part, taken along C-C inFIG. 3.

The air flow path shown inFIG. 11, via the electromagnetic valve35aarranged in the manifold upper member30a, affords communication between the air space40formed in the manifold part30and the communicating hole38aformed in the upper member30a; and via the communicating hole29, affords communication between the air flow path37formed at the front of the manifold part30and the air flow path28formed in the nozzle part20, and the nozzle22of the air sweeper23arranged on the upper surface of the nozzle part20.

The air flow path shown inFIG. 11likewise supplies the nozzle22of the air sweeper23with air from the air space40, through opening of the electromagnetic valve35a.

For example, by utilizing a timer in the color sorter1shown inFIGS. 1 and 2to periodically open the electromagnetic valve35aand jet air from the nozzle22depending on the running time of the color sorter1, or by utilizing a sensor to open the electromagnetic valve35aand jet air from the nozzle22depending on the condition of accumulation of dust or the like on the upper surface of the nozzle part20, the upper surface of the nozzle part20can be cleaned automatically. Moreover, by switching the opening/closing action of the electromagnetic valve35ato manual, the upper surface of the nozzle part20can be cleaned automatically through manual operation by a worker.

In the above manner, in the ejector system8of the present embodiment, the nozzle part20and the manifold part30are constituted such that it is possible for them to be easily assembled and separated, improving the cleaning and maintenance performance.

Moreover, in the ejector system8of the present embodiment, the nozzle part20and the manifold part30are constituted by screwing together upper and lower members, and therefore the upper and lower members can be easily separated, so that the air passages27,37formed on the opposed surfaces of the upper and lower members can be easily cleaned.

In the ejector system8of the present embodiment, at one side end of the upper surface of the nozzle part20, there has been arranged the air sweeper23provided with nozzles22that open towards the other side end of the upper surface of the nozzle part20, whereby starting material, dust, and the like accumulating on the upper surface of the nozzle part20can be cleaned automatically, and the burden of cleaning or maintenance performed by workers can be reduced.

The ejector system8of the present embodiment is constituted such that when the plurality of electromagnetic valves35a,35bare respectively arranged on the upper and lower members30a,30bconstituting the manifold part30, the phase of the electromagnetic valves35aarranged on the upper member30aand that of the electromagnetic valves35barranged on the lower member30bare made different from one another, and therefore the number of nozzle holes that open onto the front surface of the nozzle part can be increased to double, as compared with a case in which the electromagnetic valves are arranged on one member only.

In the ejector system of the aforedescribed embodiment, the nozzle part20and the manifold part30are integrated by inserting the pair of rods33a,33battached to the manifold part30into the pair of through-holes25a,25bformed in the nozzle part20, and threading and tightening the female thread parts of the fastening members26a,26bonto the distal end male thread parts of the rods33a,33bthat project out through the through-holes25a,25b; however, the nozzle part20and the manifold part30may be integrated by other means.

In the ejector system of the aforedescribed embodiment, the air flow paths27,37that are formed on the opposed surfaces of the upper and lower members of the nozzle part20and the manifold part30are constituted by slots formed in the upper surface of the lower members and slots formed in the lower surface of the upper members; however, provided that the air flow paths27,37are formed in the opposed surfaces of the upper and lower members of the nozzle part20and the manifold part30, it is acceptable for the slots constituting the air flow paths27,37to be formed in either the upper or lower member only.

In the ejector system of the aforedescribed embodiment, the nozzle part20and the manifold part30are respectively constituted by screwing together an upper and a lower member; however, these could be respectively constituted as single members. In this case, the air flow paths formed in the parts may be formed as through-holes.

In the ejector system of the aforedescribed embodiment, the air sweeper23is arranged on the upper surface of the nozzle part20; however, the arrangement of the air sweeper23is arbitrary.

In the ejector system of the aforedescribed embodiment, the electromagnetic valves35are arranged in two rows on the manifold part30; however, the electromagnetic valves35may instead be arranged in three or more rows, or arranged in a single row only, as in the prior art.

Example of Implementation of Ejector System in a Color Sorter

FIG. 12is an example of implementation of the ejector system of the present invention in a color sorter, and shows a partial enlarged view ofFIG. 2.

As shown inFIG. 12, the ejector system8of the present embodiment is fastened to the body of the color sorter by the attachment member31, which has been screwed to the upper surface at the front of the manifold upper member30a.

In the process, the ejector system8is arranged such that the nozzle part20is positioned on the flow path of the particulate matter, and the manifold part30is positioned in the interior of the sorter body.

In the ejector system8of the present embodiment, because the manifold part30is positioned in the interior of the sorter body, soiling of the electromagnetic valves by dust and the like stirred up within the flow path in association with falling of the particulate matter can be prevented.

The ejector system8of the present embodiment is not limited to application in the aforedescribed color sorter1; implementation in all manner of color sorters is possible.

The present invention is not limited to the aforedescribed embodiments; various modifications of the constitution thereof can be made, as appropriate, without departing from the scope of the claims.

INDUSTRIAL APPLICABILITY

The ejector system employed in the color sorter of the present invention has excellent cleaning and maintenance performance by virtue of a constitution whereby the nozzle part and the manifold part are integrated by a separable structure, and the application value is accordingly high.

REFERENCE SIGNS LIST

7a,7bOptical detection devices

9Particulate matter discharge trough

9aSatisfactory item discharge trough

9bUnsatisfactory item discharge trough

20aNozzle upper member

20bNozzle lower member

27Air flow paths

28Air flow paths

30aManifold upper member

30bManifold lower member

36a,36bAir line connection parts

37Air flow paths

39a,39bAir supply holes

40a,40bAir space recess parts