What is claimed is:
1. A process for purifying difluoromethane, which comprises subjecting a mixture comprising difluoromethane and hydrogen fluoride to extraction treatment with at least one extractant selected from the following (a) and (b) to separate it by liquid separation into an extractant layer comprising the difluoromethane and the extractant as the main components, and a hydrogen fluoride layer comprising the hydrogen fluoride as the main component, and separating the difluoromethane from the extractant layer:
(a) Dichloromethane
(b) Chlorofluoromethane.
2. The process according to claim 1, wherein the proportion of HF contained in the mixture is from 5 to 1000 parts by weight, per 100 parts by weight of the difluoromethane.
3. The process according to claim 1, wherein the proportion of HF contained in the mixture is from 10 to 100 parts by weight, per 100 parts by weight of the difluoromethane.
4. The process according to claim 1, wherein the amount of the extractant is from 0.3 to 30 times (by a molar ratio) to the difluoromethane contained in the mixture.
5. The process according to claim 1, wherein the amount of the extractant is from 1 to 10 times (by a molar ratio) to the difluoromethane contained in the mixture.
6. The process according to claim 1, wherein the liquid separation to obtain the extractant layer and the hydrogen fluoride layer, is carried out at a temperature of from 40 C. to 50 C. under a pressure of from 0.1 to 3 MPa.
7. The process according to claim 6, wherein the temperature is from 30 C. to 30 C.
8. The process according to claim 6, wherein the pressure is from 0.1 to 1 MPa.
9. The process according to claim 1, wherein the extractant layer is distilled to separate the difluoromethane from the extractant layer, and the extractant is returned to the step of extraction treatment.
10. The process according to claim 1, wherein the mixture is a reaction product obtained from a reaction which comprises fluorinating dichloromethane with hydrogen fluoride.
11. The process according to claim 10, wherein the hydrogen fluoride layer is returned to the reaction step to obtain the mixture, without removing the extractant and the difluoromethane contained therein.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A device for assembling a vehicle body in order to assemble a dash panel to a left side member and a right side member comprises:
at least three sets of locate units that are disposed at both sides of a base plate, hold side members through a clamping pin inserted into a tooling hole formed at a lower portion of the side members, and control the side members to move in four directions or a vertical direction by three servo motors;
a robot hanger unit disposed at the front end of an arm of a handling robot disposed at the front side of the base plate in order to load the dash panel between the side members held by the locate unit in a state in which the clamping pin is inserted into a tooling hole formed at a surface of the dash panel, and at the same time to transport the side members and the dash panel assembly to a parts unloading process;
a parts loading robot respectively disposed at both sides of rearward of the base plate so as to clamp the leftright side members, and to load the side members to the locate unit; and
a welding robot integrally provided with a spot welding gun at the front end thereof and disposed at both sides of the base plate so as to weld abutments of the side members and the dash panel,
wherein the locate unit comprises:
a main plate mounted at one side of the base plate;
a longitudinal rail mounted at the main plate in a longitudinal direction a longitudinal rail block slidably mounted at the longitudinal rail;
a longitudinal drive member connected to the longitudinal rail block in a state of being arranged on the main plate along one side of the longitudinal rail so as to slidably move the longitudinal rail block along the longitudinal rail using a rotating force;
a rail plate mounted on an upper surface of the longitudinal rail block;
a traverse rail traversely mounted on the rail plate;
a traverse rail bock slidably mounted at the traverse rail;
a traverse drive member connected to the traverse rail block in a state of being arranged on the rail plate along one side of the traverse rail so as to slidably move the traverse rail block along the traverse rail by using the rotating force;
a slide guider perpendicularly mounted at an upper surface of the traverse rail block;
a vertical slider slidably mounted on the slide guider so as to be moved upward and downward;
a vertical drive member connected to the vertical slider in a state of being arranged perpendicularly on the traverse rail block along one side of the slide guider so as to slidably move the vertical slider along the slide guider by using the rotating force; and
a pin clamping member disposed at an upper end of the vertical slider so as to hold the parts by using air pressure in a state in which a clamping pin is inserted into the tooling hole.
2. The device for assembling a vehicle body of claim 1, wherein the longitudinal drive member comprises:
a longitudinal servo motor that is mounted on the main plate along one side of the longitudinal rail through a mounting block and that is provided with a rotating shaft formed of a screw bar; and
a longitudinal screw block disposed at a surface of the longitudinal rail block so that it is engaged with the screw bar of the longitudinal servo motor.
3. The device for assembling a vehicle body of claim 1, wherein the traverse drive member comprises:
a traverse servo motor that is mounted on the rail plate through a support block along one side of the traverse rail and that is provided with a rotating shaft formed of a screw bar; and
a traverse screw block disposed at a surface of the traverse rail block, so that a vertical screw block is engaged with the screw bar of the traverse servo motor.
4. The device for assembling a vehicle body of claim 1, wherein the vertical drive member comprises:
a vertical servo motor that is perpendicularly mounted on the traverse rail block along one side of the slide guider and that is provided with a rotating shaft formed of a screw bar; and
a vertical screw block disposed at a surface of the vertical slider, and engaged with the screw bar of the vertical servo motor.
5. The device for assembling a vehicle body of claim 1, wherein the pin clamping member comprises:
an air pressure cylinder perpendicularly mounted at an upper end of the vertical slider; and
a clamping pin connected to an operating rod of the air pressure cylinder in a state of being mounted at an upper end of the air pressure cylinder so as to rotate a damper disposed therein.
6. The device for assembling a vehicle body of claim 1, wherein the robot hanger unit comprises:
a hanger frame of a double pipe structure in which the middle portion thereof is fixed to the front end of the handling robot, and aluminum expanded foam is inserted therein;
a pushing member disposed at both ends of the hanger frame so as to support both sides of the dash panel;
a central pin clamping member disposed at a lower side of the center of the hanger frame so as to insert the clamping pin into a tooling hole disposed at a surface of the dash panel and hold the dash panel and that is operated by air pressure; and
leftright pin clamping members slidably mounted at both sides of the hanger frame with respect to the center thereof through which the clamping pin is inserted into the tooling holes formed at a surface of the dash panel so as to hold the dash panel by using air pressure.
7. The device for assembling a vehicle body of claim 6, wherein the pushing member comprises:
a rod housing mounted respectively at both ends of the hanger frame;
a pushing rod slidably inserted into the rod housing;
a rubber pad mounted at the front end of the pushing rod; and
a spring mounted on the pushing rod in such a state that one end thereof is supported by the rubber pad and the other end thereof is supported by the rod housing.
8. The device for assembling a vehicle body of claim 6, wherein the central pin clamping member comprises:
a central air cylinder fixed to a lower side of the center of the hanger frame; and
a central clamping pin connected to the operating rod of the central air cylinder in a state of being mounted at the front end of the central air cylinder so as to rotate a clamper disposed therein.
9. The device for assembling a vehicle body of claim 6, wherein the leftright pin clamping members comprises:
leftright air cylinders slidably mounted at both sides thereof along an axial direction with respect to the center of the hanger frame; and
leftright clamping pins connected to the operating rod of the leftright air cylinders in a state of being mounted at the front end of the leftright air cylinders so as to rotate the damper disposed therein.
10. A device for assembling a vehicle body in order to assemble a dash panel to a left side member and a right side member comprises:
at least three sets of locate units that are disposed at both sides of a base plate, hold side members through a clamping pin inserted into a tooling hole formed at a lower portion of the side members, and control the side members to move in four directions or a vertical direction by three servo motors;
a robot hanger unit disposed at the front end of an arm of a handling robot disposed at the front side of the base plate in order to load the dash panel between the side members held by the locate unit in a state in which the clamping pin is inserted into a tooling hole formed at a surface of the dash panel, and at the same time to transport the side members and the dash panel assembly to a parts unloading process;
a parts loading robot respectively disposed at both sides of rearward of the base plate so as to clamp the leftright side members, and to load the side members to the locate unit; and
a welding robot integrally provided with a spot welding gun at the front end thereof and disposed at both sides of the base plate so as to weld abutments of the side members and the dash panel,
wherein the robot hanger unit comprises;
a hanger frame of a double pipe structure in which the middle portion thereof is fixed to the front end of the handling robot, and aluminum expanded foam is inserted therein;
a pushing member disposed at both ends of the hanger frame so as to support both sides of the dash panel;
a central pin clamping member disposed at a lower side of the center of the hanger frame so as to insert the clamping pin into a tooling hole disposed at a surface of the dash panel and hold the dash panel and that is operated by air pressure; and
leftright pin clamping members slidably mounted at both sides of the hanger frame with respect to the center thereof through which the clamping pin is inserted into the tooling holes formed at a surface of the dash panel so as to hold the dash panel by using air pressure.
11. The device for assembling a vehicle body of claim 10, wherein the locate unit comprises:
a main plate mounted at one side of the base plate;
a longitudinal rail mounted at the main plate in a longitudinal direction;
a longitudinal rail block slidably mounted at the longitudinal rail;
a longitudinal drive member connected to the longitudinal rail block in a state of being arranged on the main plate along one side of the longitudinal rail so as to slidably move the longitudinal rail block along the longitudinal rail using a rotating force;
a rail plate mounted on an upper surface of the longitudinal rail block;
a traverse rail traversely mounted on the rail plate;
a traverse rail bock slidably mounted at the traverse rail;
a traverse drive member connected to the traverse rail block in a state of being arranged on the rail plate along one side of the traverse rail so as to slidably move the traverse rail block along the traverse rail by using the rotating force;
a slide guider perpendicularly mounted at an upper surface of the traverse rail block;
a vertical slider slidably mounted on the slide guider so as to be moved upward and downward;
a vertical drive member connected to the vertical slider in a state of being arranged perpendicularly on the traverse rail block along one side of the slide guider so as to slidably move the vertical slider along the slide guider by using the rotating force; and
a pin clamping member disposed at an upper end of the vertical slider so as to hold the parts by using air pressure in a state in which a clamping pin is inserted into the tooling hole, and
wherein the longitudinal drive member comprises:
a longitudinal servo motor that is mounted on the main plate along one side of the longitudinal rail through a mounting block and that is provided with a rotating shaft formed of a screw bar; and
a longitudinal screw block disposed at a surface of the longitudinal rail block so that it is engaged with the screw bar of the longitudinal servo motor.
12. The device for assembling a vehicle body of claim 11, wherein the traverse drive member comprises:
a traverse servo motor that is mounted on the rail plate through a support block along one side of the traverse rail and that is provided with a rotating shaft formed of a screw bar; and
a traverse screw block disposed at a surface of the traverse rail block, so that a vertical screw block is engaged with the screw bar of the traverse servo motor.
13. The device for assembling a vehicle body of claim 11, wherein the vertical drive member comprises:
a vertical servo motor that is perpendicularly mounted on the traverse rail block along one side of the slide guider and that is provided with a rotating shaft formed of a screw bar; and
a vertical screw block disposed at a surface of the vertical slider, and engaged with the screw bar of the vertical servo motor.
14. The device for assembling a vehicle body of claim 11, wherein the pin clamping member comprises:
an air pressure cylinder perpendicularly mounted at an upper end of the vertical slider; and
a clamping pin connected to an operating rod of the air pressure cylinder in a state of being mounted at an upper end of the air pressure cylinder so as to rotate a clamper disposed therein.
15. The device for assembling a vehicle body of claim 10, wherein the pushing member comprises:
a rod housing mounted respectively at both ends of the hanger frame;
a pushing rod slidably inserted into the rod housing;
a rubber pad mounted at the front end of the pushing rod; and
a spring mounted on the pushing rod in such a state that one end thereof is supported by the rubber pad and the other end thereof is supported by the rod housing.
16. The device for assembling a vehicle body of claim 10, wherein the central pin clamping member comprises:
a central air cylinder fixed to a lower side of the center of the hanger frame; and
a central clamping pin connected to the operating rod of the central air cylinder in a state of being mounted at the front end of the central air cylinder so as to rotate a damper disposed therein.
17. The device for assembling a vehicle body of claim 10, wherein the leftright pin clamping members comprises:
leftright air cylinders slidably mounted at both sides thereof along an axial direction with respect to the center of the hanger frame; and
leftright clamping pins connected to the operating rod of the leftright air cylinders in a state of being mounted at the front end of the leftright air cylinders so as to rotate the damper disposed therein.