Pump unit with a magnetically driven piston

Abstract

 A pump unit for magnetically driving an article (12), including a main body (11), an article (12) and a coil (13). The main body (11) has an internal chamber. The article has a certain length and a configuration corresponding to a shape of the chamber. The article (12) is reciprocally movably positioned in the chamber. The coil (13) is wound around the main body (11) and connected with a circuit. The circuit provides a current for the coil (13) so as to drive the article (12) to reciprocally move. The chamber of the main body (11) communicates with two open ends of the main body (11). The pump unit further includes a first pair of one-way valve sections (16) and a second pair of one-way valve sections (16). The first and second pairs of one-way valve sections (16) are respectively disposed at two ends of the main body (11). When the article (12) is reciprocally moved, a fluid can be only driven by the article (12) to flow from a first position to a second position.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention is related to a device for driving a fluid, and more particularly to a pump unit for magnetically driving an article.

[0002] The conventional pumping device is used to push a fluid to flow in a pipeline. The pumping device generally includes a water wheel apparatus or a pump unit communicating with a pipeline and externally connected with a motor. The motor operates to drive the water wheel to rotate or drive the pump unit to reciprocally move for pushing the fluid. Therefore, the fluid can be circulated in the pipeline or transferred from one place to another place.

[0003] The conventional pumping device is equipped with the motor so that much room is occupied and the cost is relatively high. Also, one single pipeline system is often equipped with one single pump. Alternatively, one single pumping device can be used in cooperation with two pipeline systems. In this case, many switch valves or check valves must be mounted on the two pipeline systems. This leads to high cost and inconvenience in use.

[0004] U.S. Patent No. 6,364,003 of this applicant discloses a device in which five magnets are disposed in a chamber. The chamber is formed with several openings. A coil provided with variable current direction serves to drive one of the magnets to reciprocally move so as to alternately push two fluids. Such measure is applicable to liquid-cooled or phase-change cooling systems. Especially, this measure can suck in the cold air in the environment to serve as a heat-absorbing coolant. When assembled, it should be noted that the same poles of the five magnets are directed to each other.

SUMMARY OF THE INVENTION

[0005] It is therefore a primary object of the present invention to provide a pump unit for magnetically driving an article. The pump unit employs one single magnet for driving a fluid.

[0006] It is a further object of the present invention to provide the above pump unit which is able to drive the fluid of a pipeline system or the fluid of two independent pipeline systems.

[0007] It is still a further object of the present invention to provide the above pump unit by which it is unnecessary to equip the external pipeline system with any switch valve or check valve.

[0008] The objects of the present invention are solved with a pump unit with the features of claim 1 or 43. Preferred embodiments of the invention are disclosed in the subclaims.

[0009] According to the above object, the pump unit for magnetically driving an article of the present invention includes a main body, an article, a coil and four one-way valve sections.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention can be best understood through the following description and accompanying drawings wherein:

Fig. 1 is a sectional view of a pump unit of a first embodiment of the present invention;

Fig. 2 is a sectional view of a pump unit of a second embodiment of the present invention;

Fig. 3 is a sectional view of a pump unit of a third embodiment of the present invention;

Fig. 4 is a sectional view of a pump unit of a fourth embodiment of the present invention; and

Fig. 5 shows the operation of the pump unit of the present invention and also shows the path of the fluid.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Please refer to Fig. 1. The pump unit for magnetically driving an article of the present invention includes a main body 11, an article 12 and a coil 13.

[0012] The main body 11 can be a tubular body having a certain length and an internal chamber.

[0013] The article 12 has a certain length and a configuration corresponding to the shape of the chamber. The article 12 is reciprocally movably positioned in the chamber. The article 12 can be a magnet or a superconductor subject to the action of magnetic force.

[0014] The coil 13 is wound around the main body 11 and connected with a circuit. The circuit provides a current such as an alternate current or a periodically alternate current for the coil 13 so as to drive the article 12 to move or reciprocally move for pushing a fluid on one side or two sides of the article 12.

[0015] In addition, at least an outer circumference of the main body is disposed with or formed of a magnetically conductive material such as silicon steel, iron, amorphous material (such as amorphous Si), permanent magnet and superconductor. The main body 11 can be formed of a sheet body spirally continuously wound into a circular tubular body. Alternatively, the main body 11 can be composed of multiple circular sleeves having different diameters and fitted with each other.

[0016] Referring to Fig. 2, another structure of the main body 11 includes a circular tubular body 111 having a chamber and a magnetic conductor 112 enclosing the circular tubular body 111. The magnetic conductor 112 can be made of silicon steel, iron, amorphous material, permanent magnet or superconductor. The magnetic conductor 112 can be formed of a sheet body spirally continuously wound around the circular tubular body 111. Alternatively, the magnetic conductor 112 can be composed of multiple circular sleeves with different diameters. The sleeves are fitted around the circular tubular body 111 and fitted with each other.

[0017] The above structure serves as a power source for a reciprocating pump. The coil 13 is wound around the magnetically conductive material or the magnetic conductor 112 to achieve better magnetic flux for acting on the article 12. Such design is also for lowering the temperature of the coil 13.

[0018] Again referring to Fig. 2, the present invention further includes a magnetic path section 14 enclosing the coil 13. The main body 11 has two open ends. The magnetic path section 14 can be made of metal material for effectively conducting the magnetic field generated by the coil 13 to drive the article 12. Two ends of the magnetic path section 14 are bent and extend through two ends of the main body 11 into the main body by a certain depth. Alternatively, the two ends of the magnetic path section 14 are bridged with another magnetic path section extending to two ends of the main body 11. Accordingly, the magnetic field can be more effectively conducted and another magnetic field can be generated to act on the article 12. In the case that the main body 11 includes a magnetically conductive material, the extending portion of the magnetic path section 14 or the bridged portion of the magnetic path section 14 will not contact with the magnetically conductive material of the main body 11 so as to avoid unexpected magnetic path. This is for achieving better electromagnetic effect.

[0019] Referring to Figs. 1 and 2, the present invention further includes at least one restricting section 15 disposed in the chamber on one side of the article 12. The restricting section 15 serves to restrict the travel of one end of the article 12, whereby a greater electromagnetic force is applied to the article 12 in a predetermined position. This is because in a certain position, a greater composite magnetic force is achievable.

[0020] Referring to Figs. 1 and 2, the chamber communicates with two open ends of the main body 11. The present invention further includes a first pair of one-way valve sections 16 and a second pair of one-way valve sections 16. The first and second pairs of one-way valve sections 16 are respectively disposed at two ends of the main body 11, whereby the fluid can only flow from a first position to a second position. Accordingly, the present invention can transfer the fluid by means of reciprocating the article 12.

[0021] Referring to Figs. 3, 4 and 5, the first and second positions are outside the pump unit. One of the first pair of one-way valve sections 16 on one side of the article 12 and one of the second pair of one-way valve sections 16 on the other side of the article 12 communicate with the first position. The remaining two one-way valve sections 16 communicate with the second position. The present invention further includes an enclosing member 17 enclosing the coil 13 and the four one-way valve sections 16. A first flow way 171 is formed in the first position for communicating with the one-way valve sections 16 in the first position. A second flow way 172 is formed in the second position for communicating with the one-way valve sections 16 in the second position. Two ends of the enclosing member 17 respectively serve as an inlet and an outlet of the fluid. In other words, the fluid can sequentially flow through the first flow way 171, the chamber and the second flow way 172.

[0022] In the pump unit of the present invention, each one-way valve section 16 has a third flow way 62 and a valve 64. The third flow way 62 has a middle section and two ends. The middle section has a cross-sectional area larger than a cross-sectional area of the two ends of the third flow way 62. A stopper section 66 is further disposed in the middle section of the third flow way 62.

[0023] The valve 64 is movably disposed in the middle section of the third flow way 62 and positioned between the stopper section 66 and one end of the third flow way 62. The valve 64 has a cross-sectional area smaller than that of the middle section of the third flow way 62, while being larger than that of the ends of the third flow way 62. When the valve 64 moves to the stopper section 66, the valve 64 will not hinder the fluid from flowing through the third flow way 62. Reversely, when the valve 62 moves away from the stopper section 66, the valve 64 will block the third flow way 62 to prevent the fluid from flowing through the third flow way 62.

[0024] The pump unit of the present invention can further include another coil extending in a direction in which the article 12 moves. The other coil is adjacent to the coil 13 and wound around the main body 11. The two coils can be respectively independently connected to two circuits. Alternatively, the coils can be interconnected and then connected to a circuit. The two coils can provide magnetic lines in different directions to more effectively act on and drive the article 12.

[0025] According to the above arrangement, the pump unit of the present invention has the following advantages:

1. The power section, transmission section and pumping section of the conventional pump are integrated to minify the volume of the pump.

2. It is quite convenient to assemble the components of the pump unit of the present invention.

3. It is unnecessary to equip the external pipeline system of the present invention with any switch valve or check valve.

[0026] The above embodiments are only used to illustrate the present invention, not intended to limit the scope thereof. Many modifications of the above embodiments can be made without departing from the spirit of the present invention.

Claims

1. A pump unit for magnetically driving an article (12), comprising:

a main body (11) having an internal chamber, at least an outer circumference of the main body (11) being disposed with or formed of a magnetically conductive material;

the article (12) having a certain length and a configuration corresponding to a shape of the chamber, the article (12) being reciprocally movably positioned in the chamber and drivable by magnetic force; and

a coil (13) wound around the main body (11) and connected with a circuit, the circuit providing a current for the coil so as to drive the article (12) to reciprocally move.

2. The pump unit for magnetically driving the article (12) as claimed in claim 1, wherein the main body (11) is selected from the group consisting of silicon steel, iron, amorphous material and permanent magnet.

3. The pump unit for magnetically driving the article (12) as claimed in claim 1, wherein the main body (11) is a circular tubular body (111) formed of a sheet body which is continuously wound to form the main body (11).

4. The pump unit for magnetically driving the article (12) as claimed in claim 2, wherein the main body (11) is a circular tubular body (111) formed of a sheet body which is continuously wound to form the main body (11).

5. The pump unit for magnetically driving the article (12) as claimed in claim 1, wherein the main body (11) is a circular tubular body (111) composed of multiple circular sleeves having different diameters and fitted with each other to form the main body (11).

6. The pump unit for magnetically driving the article (12) as claimed in claim 2, wherein the main body (11) is a circular tubular body (111) composed of multiple circular sleeves having different diameters and fitted with each other to form the main body (11).

7. The pump unit for magnetically driving the article (12) as claimed in claim 1, wherein the main body (11) includes a circular tubular body (111) and a magnetic conductor (112) enclosing the circular tubular body (111).

8. The pump unit for magnetically driving the article (12) as claimed in claim 7, wherein the magnetic conductor (112) is selected from the group consisting of silicon steel, iron, amorphous material and permanent magnet.

9. The pump unit for magnetically driving the article (12) as claimed in claim 7, wherein the magnetic conductor (112) is formed of a sheet body continuously wound around the circular tubular body (111).

10. The pump unit for magnetically driving the article (12) as claimed in claim 8, wherein the magnetic conductor (112) is formed of a sheet body continuously wound around the circular tubular body (111).

11. The pump unit for magnetically driving the article (12) as claimed in claim 7, wherein the magnetic conductor (112) is composed of multiple circular sleeves with different diameters, the sleeves being sequentially fitted around the circular tubular body (111) and fitted with each other.

12. The pump unit for magnetically driving the article (12) as claimed in claim 8, wherein the magnetic conductor (112) is composed of multiple circular sleeves with different diameters, the sleeves being sequentially fitted around the circular tubular body (111) and fitted with each other.

13. The pump unit for magnetically driving the article (12) as claimed in claim 1, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

14. The pump unit for magnetically driving the article (12) as claimed in claim 2, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

15. The pump unit for magnetically driving the article (12) as claimed in claim 3, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

16. The pump unit for magnetically driving the article (12) as claimed in claim 4, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

17. The pump unit for magnetically driving the article (12) as claimed in claim 5, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

18. The pump unit for magnetically driving the article (12) as claimed in claim 6, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

19. The pump unit for magnetically driving the article (12) as claimed in claim 7, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil 813) to drive the article (12).

20. The pump unit for magnetically driving the article (12) as claimed in claim 8, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

21. The pump unit for magnetically driving the article (12) as claimed in claim 9, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

22. The pump unit for magnetically driving the article (12) as claimed in claim 10, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

23. The pump unit for magnetically driving the article (12) as claimed in claim 11, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

24. The pump unit for magnetically driving the article (12) as claimed in claim 12, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

25. The pump unit for magnetically driving the article (12) as claimed in claim 13, wherein the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the main body (11) into the main body (11) by a certain depth.

26. The pump unit for magnetically driving the article (12) as claimed in claim 14, wherein the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the main body (11) into the main body (11) by a certain depth, the magnetic path section (14) being not in contact with the main body (11).

27. The pump unit for magnetically driving the article (12) as claimed in claim 15, wherein the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the main body (11) into the main body (11) by a certain depth.

28. The pump unit for magnetically driving the article (12) as claimed in claim 16, wherein the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the main body (11) into the main body (11) by a certain depth, the magnetic path section (14) being not in contact with the main body (11).

29. The pump unit for magnetically driving the article (12) as claimed in claim 17, wherein the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the main body (11) into the main body (11) by a certain depth.

30. The pump unit for magnetically driving the article (12) as claimed in claim 18, wherein the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the main body (11) into the main body (11) by a certain depth, the magnetic path section (14) being not in contact with the main body (11).

31. The pump unit for magnetically driving the article (12) as claimed in claim 19, wherein the circular tubular body (111) of the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the circular tubular body (111) into the circular tubular body (111) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

32. The pump unit for magnetically driving the article (12) as claimed in claim 20, wherein the circular tubular body (111) of the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the circular tubular body (111) into the circular tubular body (111) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

33. The pump unit for magnetically driving the article (12) as claimed in claim 21, wherein the circular tubular body (111) of the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the circular tubular body (111) into the circular tubular body (111) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

34. The pump unit for magnetically driving the article (12) as claimed in claim 22, wherein the circular tubular body (111) of the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the circular tubular body (111) into the circular tubular body (111) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

35. The pump unit for magnetically driving the article (12) as claimed in claim 23, wherein the circular tubular body (111) of the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the circular tubular body (111) into the circular tubular body (111) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

36. The pump unit for magnetically driving the article (12) as claimed in claim 24, wherein the circular tubular body (111) of the main body (11) has two open ends, two ends of the magnetic path section (14) being bent and extending through the two open ends of the circular tubular body (111) into the circular tubular body (111) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

37. The pump unit for magnetically driving the article (12) as claimed in claim 1, further comprising a restricting section (15) disposed in the chamber for restricting the travel of the article (12).

38. The pump unit for magnetically driving the article (12) as claimed in claim 7, further comprising a restricting section (15) disposed in the chamber for restricting the travel of the article (12).

39. The pump unit for magnetically driving the article (12) as claimed in claim 13, further comprising a restricting section (15) disposed in the chamber for restricting the travel of the article (12).

40. The pump unit for magnetically driving the article (12) as claimed in claim 19, further comprising a restricting section (15) disposed in the chamber for restricting the travel of the article (12).

41. The pump unit for magnetically driving the article (12) as claimed in claim 25, further comprising a restricting section (15) disposed in the chamber for re-stricting the travel of the article (12).

42. The pump unit for magnetically driving the article (12) as claimed in claim 31, further comprising a restricting section (15) disposed in the chamber for restricting the travel of the article (12).

43. A pump unit for driving a fluid from a first position to a second position, comprising:

a main body (11) having an internal chamber and two open ends communicating with the internal chamber;

an article (12) having a certain length and a configuration corresponding to a shape of the chamber, the article (12) being reciprocally movably positioned in the chamber between the two open ends of the main body (11);

a coil (13) wound around the main body (11) and connected with a circuit, the circuit providing a current for the coil (13) so as to drive the article (12) to reciprocally move; and

a first pair of one-way valve sections (16) and a second pair of one-way valve sections (16), the first and second pairs of one-way valve sections 816) being respectively disposed at the two ends of the main body (11), whereby the fluid can only flow from the first position to the second position.

44. The pump unit as claimed in claim 43, wherein at least an outer circumference of the main body (11) is disposed with or formed of a magnetically conductive material.

45. The pump unit as claimed in claim 44, wherein the main body (11) is selected from the group consisting of silicon steel, iron, amorphous material and permanent magnet.

46. The pump unit as claimed in claim 44, wherein the main body (11) is a circular tubular body (111) formed of a sheet body which is continuously wound to form the main body (11).

47. The pump unit as claimed in claim 45, wherein the main body (11) is a circular tubular body (111) formed of a sheet body which is continuously wound to form the main body (11).

48. The pump unit as claimed in claim 44, wherein the main body (11) is a circular tubular body (111) composed of multiple circular sleeves having different diameters and fitted with each other to form the main body (11).

49. The pump unit as claimed in claim 45, wherein the main body (11) is a circular tubular body (111) composed of multiple circular sleeves having different diameters and fitted with each other to form the main body (11).

50. The pump unit as claimed in claim 44, wherein the main body (11) includes a circular tubular body (111) and a magnetic conductor enclosing the circular tubular body (111) .

51. The pump unit as claimed in claim 50, wherein the magnetic conductor is selected from the group consisting of silicon steel, iron, amorphous material and permanent magnet.

52. The pump unit as claimed in claim 50, wherein the magnetic conductor is formed of a sheet body continuously wound around the circular tubular body (111).

53. The pump unit as claimed in claim 51, wherein the magnetic conductor is formed of a sheet body continuously wound around the circular tubular body (111).

54. The pump unit as claimed in claim 50, wherein the magnetic conductor is composed of multiple circular sleeves with different diameters, the sleeves being sequentially fitted around the circular tubular body (111) and fitted with each other.

55. The pump unit as claimed in claim 51, wherein the magnetic conductor is composed of multiple circular sleeves with different diameters, the sleeves being sequentially fitted around the circular tubular body (111) and fitted with each other.

56. The pump unit as claimed in claim 43, further comprising a magnetic path section enclosing the coil (13), the magnetic path section serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

57. The pump unit as claimed in claim 44, further comprising a magnetic path section enclosing the coil (13), the magnetic path section serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

58. The pump unit as claimed in claim 46, further comprising a magnetic path section enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

59. The pump unit as claimed in claim 48, further comprising a magnetic path section enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

60. The pump unit as claimed in claim 50, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

61. The pump unit as claimed in claim 52, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

62. The pump unit as claimed in claim 54, further comprising a magnetic path section (14) enclosing the coil (13), the magnetic path section (14) serving to effectively conduct the magnetic field generated by the coil (13) to drive the article (12).

63. The pump unit as claimed in claim 56, wherein two ends of the magnetic path section (14) are bent and extend through the two open ends of the main body (11) into the main body (11) by a certain depth.

64. The pump unit as claimed in claim 57, wherein two ends of the magnetic path section (14) are bent and extend through the two open ends of the main body (11) into the main body (11) by a certain depth.

65. The pump unit as claimed in claim 58, wherein two ends of the magnetic path section (14) are bent and extend through the two open ends of the main body (11) into the main body (11) by a certain depth, the magnetic path section (14) being not in contact with the main body (11).

66. The pump unit as claimed in claim 59, wherein two ends of the magnetic path section (14) are bent and extend through the two open ends of the main body (11) into the main body (11) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

67. The pump unit as claimed in claim 60, wherein two ends of the magnetic path section (14) are bent and extend through the two open ends of the main body (11) into the main body (11) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

68. The pump unit as claimed in claim 61, wherein two ends of the magnetic path section (14) are bent and extend through the two open ends of the main body (11) into the main body (11) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

69. The pump unit as claimed in claim 62, wherein two ends of the magnetic path section (14) are bent and extend through the two open ends of the main body (11) into the main body (11) by a certain depth, the magnetic path section (14) being not in contact with the magnetic conductor.

70. The pump unit as claimed in claim 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68 or 69, wherein the first and second positions are outside the pump unit, one of the first pair of one-way valve sections (16) on one side of the article (12) and one of the second pair of one-way valve sections (16) on the other side of the article (12) communicating with the first position, the remaining two one-way valve sections (16) communicating with the second position, said pump unit further comprising an enclosing member (17) enclosing the coil (13) and the four one-way valve sections (16), a first flow way (171) being formed in the first position for communicating with the one-way valve sections (16) in the first position, a second flow way (172) being formed in the second position for communicating with the one-way valve sections (16) in the second position.

71. The pump unit as claimed in claim 43, 44, 50, 56, 57, 63 or 64, further comprising a restricting section (15) disposed in the chamber for restricting the travel of the article (12).

72. The pump unit as claimed in claim 70, further comprising a restricting section (15) disposed in the chamber for restricting the travel of the article (12).

73. The pump unit as claimed in claim 43, 44, 50, 56, 57, 63 or 64, wherein each one-way valve section (16) has a third flow way (62) and a valve (64), the third flow way (62) having a middle section and two ends, the middle section having a cross-sectional area larger than a cross-sectional area of the two ends of the third flow way (62), a stopper section (66) being further disposed in the middle section of the third flow way (62), the valve (64) being movably disposed in the middle section of the third flow way (62) and positioned between the stopper section (66) and one end of the third flow way (62), the valve (64) having a cross-sectional area smaller than that of the middle section of the third flow way (62), while being larger than the cross-sectional area of the ends of the third flow way (62), whereby when the valve (64) moves to the stopper section (66), the valve (64) will not hinder the fluid from flowing through the third flow way (62), while when the valve (64) moves away from the stopper section (66), the valve (64) will block the third flow way (62) to prevent the fluid from flowing through the third flow way (62).

74. The pump unit as claimed in claim 70, wherein each one-way valve section (16) has a third flow way (62) and a valve (64), the third flow (62) way having a middle section and two ends, the middle section having a cross-sectional area larger than a cross-sectional area of the two ends of the third flow way (62), a stopper section (66) being further disposed in the middle section of the third flow way (62), the valve (64) being movably disposed in the middle section of the third flow way (62) and positioned between the stopper section (55) and one end of the third flow way (62), the valve (64) having a cross-sectional area smaller than that of the middle section of the third flow way (62), while being larger than the cross-sectional area of the ends of the third flow way (62), whereby when the valve (64) moves to the stopper section (66), the valve (64) will not hinder the fluid from flowing through the third flow way (62), while when the valve (64) moves away from the stopper section (66), the valve (64) will block the third flow way (62) to prevent the fluid from flowing through the third flow way (62).

75. The pump unit as claimed in claim 71, wherein each one-way valve section (16) has a third flow way (62) and a valve (64), the third flow way (62) having a middle section and two ends, the middle section:having a cross-sectional area larger than a cross-sectional area of the two ends of the third flow way (62), a stopper section (66) being further disposed in the middle section of the third flow way (62), the valve (64) being movably disposed in the middle section of the third flow way (62) and positioned between the stopper section (66) and one end of the third flow way (62), the valve (64) having a cross-sectional area smaller than that of the middle section of the third flow way (62), while being larger than the cross-sectional area of the ends of the third flow way (62), whereby when the valve (64) moves to the stopper section (66), the valve (64) will not hinder the fluid from flowing through the third flow way (62), while when the valve (64) moves away from the stopper section (66), the valve (64) will block the third flow way (62) to prevent the fluid from flowing through the third flow way (62).

76. The pump unit as claimed in claim 72, wherein each one-way valve section (16) has a third flow way (62) and a valve (64), the third flow way (62) having a middle section and two ends, the middle section having a cross-sectional area larger than a cross-sectional area of the two ends of the third flow way (62), a stopper section (66) being further disposed in the middle section of the third flow way (62), the valve (64) being movably disposed in the middle section of the third flow way (62) and positioned between the stopper section (66) and one end of the third flow way (62), the valve (64) having a cross-sectional area smaller than that of the middle section of the third flow way (62), while being larger than the cross-sectional area of the ends of the third flow way (62), whereby when the valve (64) moves to the stopper section (66), the valve (64) will not hinder the fluid from flowing through the third flow way (62), while when the valve (64) moves away from the stopper section (66), the valve (64) will block the third flow way (62) to prevent the fluid from flowing through the third flow way (62).

77. The pump unit as claimed in claim 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44 or 50, further comprising another coil extending in a direction in which the article (12) moves, the other coil being adjacent to the coil (13) and wound around the main body (11), the two coils serving to provide magnetic lines in different directions.

78. The pump unit as claimed in claim 70, further comprising another coil extending in a direction in which the article (12) moves, the other coil being adjacent to the coil (13) and wound around the main body (11), the two coils serving to provide magnetic lines in different directions.

79. The pump unit as claimed in claim 71, further comprising another coil extending in a direction in which the article (12) moves, the other coil being adjacent to the coil (13) and wound around the main body (11), the two coils serving to provide magnetic lines in different directions.

80. The pump unit as claimed in claim 72, further comprising another coil extending in a direction in which the article (12) moves, the other coil being adjacent to the coil (13) and wound around the main body (11), the two coils serving to provide magnetic lines in different directions.

81. The pump unit as claimed in claim 73, further comprising another coil extending in a direction in which the article (12) moves, the other coil being adjacent to the coil (13) and wound around the main body (11), the two coils serving to provide magnetic lines in different directions.

82. The pump unit as claimed in claim 74, further comprising another coil extending in a direction in which the article (12) moves, the other coil being adjacent to the coil (13) and wound around the main body (11), the two coils serving to provide magnetic lines in different directions.

83. The pump unit as claimed in claim 75, further comprising another coil extending in a direction in which the article (12) moves, the other coil being adjacent to the coil (13) and wound around the main body (11), the two coils serving to provide magnetic lines in different directions.

84. The pump unit as claimed in claim 76, further comprising another coil extending in a direction in which the article (12) moves, the other coil being adjacent to the coil (13) and wound around the main body (11), the two coils serving to provide magnetic lines in different directions.

Drawing