1. A linear actuator with a dustproof mechanism, comprising:
a ball screw;
a movable stage including a ball screw nut that engages the ball screw, the movable stage capable of making linear reciprocating motion in an axial direction of the ball screw in response to a rotary motion of the ball screw;
a housing member disposed to cover at least the ball screw;
an opening formed in the housing member along a path along which the movable stage travels; and
a dustproof belt disposed inside the housing member to block the opening,
the movable stage including a detouring device that allows a portion of the dustproof belt that overlaps with the movable stage to detour in order to move the movable stage along the opening with the opening remaining blocked with the dustproof belt; and
end plate covers covering the ends of the housing member, each of the end plate covers being shaped to cover areas of the housing member where the dustproof belt is disposed, each of the end plate covers including a flange disposed in a position facing the location where the dustproof belt is disposed in the housing member.
2. The linear actuator with a dustproof mechanism according to claim 1,
wherein each of the end plate covers includes an elastic member at the location where the end plate cover comes into contact with the housing member.
3. The linear actuator with a dustproof mechanism according to claim 2,
wherein the dustproof belt has attachment holes for fixing the dustproof belt to the housing member, the attachment holes being formed of four attachment holes, two of said attachment holes at each end of the dustproof belt, and formed in a periphery of the dustproof belt.
4. The linear actuator with a dustproof mechanism according to claim 2,
wherein the detouring device provided on the movable stage includes a plurality of rotatable rollers that engage the dustproof belt, and
at least the surface of each of the plurality of rollers is made of a resin material.
5. The linear actuator with a dustproof mechanism according to claim 1,
wherein the dustproof belt has attachment holes for fixing the dustproof belt to the housing member, the attachment holes being formed of four attachment holes, two of said attachment holes at each end of the dustproof belt, and formed in a periphery of the dustproof belt.
6. The linear actuator with a dustproof mechanism according to claim 1,
wherein the detouring device provided on the movable stage includes a plurality of rotatable rollers that engage the dustproof belt, and
at least the surface of each of the plurality of rollers is made of a resin material.
7. A linear actuator with a dustproof mechanism, comprising:
a ball screw;
a movable stage including a ball screw nut that engages the ball screw, the movable stage capable of making linear reciprocating motion in the axial direction of the ball screw in response to rotary motion of the ball screw;
a housing member disposed to cover at least the ball screw;
an opening formed in the housing member along the path along which the movable stage travels; and
a dustproof belt disposed inside the housing member to block the opening,
the movable stage including a detouring device that allows the portion of the dustproof belt that overlaps with the movable stage to detour in order to move the movable stage along the opening with the opening remaining blocked with the dustproof belt; and
a dust collection device for confining dust in the housing member located at an end of the housing member, the dust collection device including a dust collection compartment having an airtight connection to an end of the housing member, a communication hole that allows the interior of the dust collection compartment to communicate with the interior of the housing member, and a sucking port through which dust in the dust collection compartment is discharged.
8. The linear actuator with a dustproof mechanism according to claim 7,
wherein an exhaust device is formed at the communication hole.
9. The linear actuator with a dustproof mechanism according to claim 8,
wherein the exhaust device is a fan.
10. The linear actuator with a dustproof mechanism according to claim 8,
wherein the dustproof belt has attachment holes for fixing the dustproof belt to the housing member, the attachment holes being formed of four attachment holes, two of said attachment holes at each end of the dustproof belt, and formed in a periphery of the dustproof belt.
11. The linear actuator with a dustproof mechanism according to claim 9,
wherein the dustproof belt has attachment holes for fixing the dustproof belt to the housing member, the attachment holes being formed of four attachment holes, two of said attachment holes at each end of the dustproof belt, and formed in a periphery of the dustproof belt.
12. The linear actuator with a dustproof mechanism according to claim 7,
wherein the dustproof belt has attachment holes for fixing the dustproof belt to the housing member, the attachment holes being formed of four attachment holes, two of said attachment holes at each end of the dustproof belt, and formed in a periphery of the dustproof belt.
13. The linear actuator with a dustproof mechanism according to claim 11,
wherein the dustproof belt has attachment holes for fixing the dustproof belt to the housing member, the attachment holes being formed of four attachment holes, two of said attachment holes at each end of the dustproof belt, and formed in a periphery of the dustproof belt.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A process for extracting secoisolariciresinol diglycoside (SDG) from de-fatted flaxseed comprising:
(a) contacting defatted flaxseed with an extraction solvent comprising acetone and water;
(b) extracting said de-fatted flaxseed with the extraction solvent to extract SDG into said extraction solvent; and
(c) separating residual solids from the SDG-containing extract.
2. The process of claim 1 wherein the extraction solvent comprises acetone and water at proportions ranging from about 35% acetone65% water to about 65% acetone to about 35% water.
3. The process of claim 1 wherein the weight the of extraction solvent to the weight of the de-fatted flaxseed is at least about 6:1.
4. The process of claim 3 wherein the weight the of extraction solvent to the weight of the de-fatted flaxseed is in the range of about 12:1 to about 16:1.
5. The process of claim 1 further comprising:
(d) removing acetone from said extract;
(e) subjecting said SDG-containing extract to hydrolysis to liberate free SDG; and
(f) recovering said free SDG.
6. The process of claim 1 wherein the step of extracting the de-fatted flaxseed is carried out at an elevated temperature.
7. The process of claim 6 wherein the step of extracting the de-fatted flaxseed is carried out at acetone reflux.
8. The process of claim 1 wherein the step of separating the residual solids from the SDG-containing containing extract is carried out at an elevated temperature to retain the SDG in solution.
9. The process of claim 1 further comprising:
(d) removing acetone from said extract;
(e) lowering the pH of said extract to precipitate SDG;
(f) subjecting said precipitated SDG to hydrolysis to liberate free SDG; and
(g) recovering said free SDG.
10. The process of claim 9 wherein step (f) comprises alkaline hydrolysis.
11. The process of claim 10 wherein said alkaline hydrolysis comprises adding calcium hydroxide to an aqueous slurry containing said precipitated SDG to provide an alkaline mixture having a pH of about 10 to about 13.
12. The process of claim 11 wherein said alkaline hydrolysis is carried out at an elevated temperature.
13. The process of claim 9 wherein said step of recovering free SDG comprises removing water by lyophilization, spray drying, vacuum drying, or other evaporative means.
14. The process of claim 1 wherein SDG in said SDG-containing extract is obtained in a yield of at least about 70%.
15. A process for preparing a secoisolariciresinol diglycoside (SDG) concentrate from de-fatted flaxseed comprising:
(a) extracting de-fatted flaxseed with an extraction solvent comprising acetone and water to obtain an SDG-containing extract;
(b) separating residual solids from the SDG-containing extract;
(c) removing acetone to provide an acetone stripped extract;
(d) lowering the pH of the acetone stripped extract to precipitate SDG;
(e) separating precipitated SDG from the acetone stripped extract;
(f) subjecting the precipitated SDG in an aqueous slurry to hydrolysis to liberate free SDG; and
(g) recovering the free SDG from the aqueous slurry.
16. The process of claim 15 wherein said recovering step comprises adjusting the pH of the aqueous slurry and removing water by lyophilization, spray drying, vacuum drying, or other evaporative means.
17. The process of claim 15 wherein said hydrolysis comprises adding calcium hydroxide to the aqueous slurry containing said precipitated SDG to provide an alkaline mixture having a pH of about 10 to about 13.
18. The process of claim 17 wherein:
hydrolysis is carried out at an elevated temperature; then
insolubles in the aqueous slurry are separated from the aqueous slurry by filtration or centrifugation at an elevated temperature; and
phosphoric acid is added to the filtrate or centrate to lower the pH.
19. The process of claim 18 wherein said recovering step comprises removing water by lyophilization, spray drying, vacuum drying, or other evaporative means to provide an SDG concentrate in a yield of at least about 70%.
20. An SDG concentrate produced by the process of claim 19.