Abstract:
Surface treatment equipment in which a working mechanism housed in a surface treatment tank is moved up and down while keeping the tank in a vacuum state, and the working mechanism can be rotated or oscillated, is provided.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a surface treatment equipment including a power transmission mechanism allowing a surface treatment cage, storing an object to be processed thereinside for performing surface treatments such as a corrosion-proof, washing, barreling, and plating treatments, to be rotatable and vertically movable in a pressure-resistant tank in a vacuum. 
         [0002]    Patent Document 1 discloses a prior art washing equipment washing an object to be washed by rotating and vertically moving in a washing tank thereof. In such a washing equipment, a lower end side of a drive shaft is inserted into the washing tank, and an upper end side of the drive shaft is protruded from the washing tank. Such an upper end side of the drive shaft is connected with a vertical movement mechanism allowing the drive shaft to be vertically movable. A rotation drive mechanism allowing the drive shaft to be rotatably movable is disposed to an upper end of the drive shaft, and a rotation table is disposed to a lower end of the drive shaft through a rotation transmission mechanism transmitting driving force of the drive shaft. 
         [0003]    The rotation drive mechanism is operated to rotatably drive the drive shaft while the vertical movement mechanism is operated to vertically move the drive shaft in a state that the object to be washed is secured on the rotation table, so that the object to be washed is rotatable and is movable up and down. Accordingly, the object to be washed rotates and/or moves up and down, so that washing operation is performed. The washing equipment disclosed in the Patent Document 1 is used based on a premise that the inside of the washing tank is at a normal pressure. 
         [0004]    On the other hand, in a case where washing operation is performed in a state that the washing tank maintains vacuum thereinside, good effect is obtained as is known. For example, in a case where ultrasonic cleaning is performed in a state that the washing tank is in the vacuum, not only an ultrasonic wave is less attenuated compared to a case of performing the ultrasonic cleaning at the normal pressure, but also a washing effect is enhanced by exhausting the air adhered to an undulated area. Moreover, in a case where objects to be processed contact one another or are placed one on another in the surface treatment operation excluding the washing operation, for example, plating, performed in the vacuum, a surface treatment agent permeates small portions, thereby uniformly performing the surface treatment. 
         [0000]    Patent Document 1: Japanese Patent Publication No. S63-24754 
       SUMMARY OF THE INVENTION 
       [0005]    Since the washing equipment disclosed in the above Patent Document 1 is used in a state that the inside of the washing tank is at the normal pressure, the inside of the washing tank is not sealed in a pressure-resistant manner and remains at the normal pressure. Consequently, the washing operation cannot be performed in a vacuum atmosphere using such a washing equipment. 
         [0006]    The present invention is proposed in consideration of the aforementioned conventional situations and is intended to provide a surface treatment equipment capable of vertically moving a working mechanism stored inside a surface treatment tank and capable of performing operation such as rotation and oscillation in a working mechanism portion according to a surface treatment object while maintaining a vacuum inside the surface treatment tank. 
         [0007]    The present invention is proposed in consideration of the aforementioned conventional situations and includes: a pressure-resistant tank capable of being in a vacuum thereinside; and a pressure-resistant casing, having a cylindrical shape, inserting a lower end side thereof into the pressure-resistant tank while protruding an upper end side thereof outwardly from the pressure-resistant tank and capable of moving vertically by connecting a vertical movement mechanism to a protrusion portion. Such a casing is resistant to the pressure, so that the casing unlikely receives damages, and the equipment can be used in a stable state in a case where the casing is disposed inside the pressure-resistant tank in the vacuum. The pressure-resistant casing may include a pressure-resistant storage unit storing a rotation transmission mechanism (described later) in a lower portion thereof. The vertical movement mechanism may be a hydraulic cylinder or a pneumatic cylinder or may be a screw or a chain block and the like. 
         [0008]    Moreover, the present invention includes: a rotation drive mechanism disposed to the protrusion portion of the pressure-resistant casing; a drive shaft, disposed to and penetrating the pressure-resistant casing, capable of rotating by connecting to the rotation drive mechanism; and a working mechanism transmitting driving force of the drive shaft through the rotation transmission mechanism connected to a lower portion of the drive shaft and performing surface treatment operation. The working mechanism may transmit the driving force of the drive shaft to a rotation transmission roller or a transfer chain by coupling a driven shaft including the rotation transmission roller or the transfer chain to the rotation drive mechanism, and may be capable of rotating or oscillating a surface treatment cage placed on the rotation transmission roller or the transfer chain. Moreover, the working mechanism may transmit the driving force of the drive shaft to a rotation table by coupling the driven shaft including the rotation table to the rotation drive mechanism, and may be capable of rotating the surface treatment cage placed on the rotation table. Moreover, the driving force of the drive shaft may be transmitted, and an optional working mechanism may be formed. 
         [0009]    Moreover, the present invention includes: a pressure-resistant vacuum sealing member disposed to an outside air communication portion between the pressure-resistant tank and the pressure-resistant casing for maintaining air-tightness inside the pressure-resistant tank by a vertical movement of the pressure-resistant casing; and a drive vacuum sealing member disposed to an outside air communication portion between the pressure-resistant casing and the drive shaft or/and the rotation transmission mechanism for maintaining the air-tightness inside the pressure-resistant tank by rotation of the drive shaft or/and the rotation transmission mechanism. The pressure-resistant vacuum sealing member responding to the vertical movement and the drive vacuum sealing member responding to the rotation are disposed, thereby respectively maintaining the air-tightness in the outside air communication portion between the pressure-resistant tank and the pressure-resistant casing and the outside air communication portion between pressure-resistant casing and the drive shaft or/and the rotation transmission mechanism. Accordingly, each of the vertical movement of the pressure-resistant casing and the rotation of the drive shaft can be performed while maintaining the vacuum inside the pressure-resistant tank. 
         [0010]    The pressure-resistant vacuum sealing member maintains the air-tightness in response to the vertical movement of the pressure-resistant casing, and does not respond to the rotation of the drive shaft or/and the rotation transmission mechanism. The drive vacuum sealing member maintains the air-tightness in response to the rotation of the drive shaft or/and the rotation transmission mechanism, and does not respond to the vertical movement of the pressure-resistant casing. 
         [0011]    According to the present invention with the structure described above, the pressure-resistant vacuum sealing member is disposed to the outside air communication portion between the pressure-resistant tank and the pressure-resistant casing, so that the pressure-resistant casing and the drive shaft are vertically movable in a state that the outside air communication portion between the pressure-resistant tank and the pressure-resistant casing is sealed. Moreover, the drive vacuum sealing member is disposed to the outside air communication portion between the pressure-resistant casing and the drive shaft or/and the rotation transmission mechanism, so that the drive shaft or/and the rotation transmission mechanism is/are rotatable in a state that the outside air communication portion between the pressure-resistant casing and the drive shaft or/and the rotation transmission mechanism is sealed. 
         [0012]    Regarding such sealing, the pressure-resistant vacuum sealing member maintains the air-tightness in response only to the vertical movement of the pressure-resistant casing, and does not respond to a rotation portion including the drive shaft or/and the rotation transmission mechanism. Moreover, the drive vacuum sealing member maintains the air-tightness in response only to the rotation of the drive shaft or/and the rotation transmission mechanism, and does not respond to the vertical movement of the pressure-resistant casing. Therefore, each of the sealing members is not applied with an unreasonable load, thereby obtaining a stable vacuum sealing effect for a prolonged period. As a result, the vertical movement of the pressure-resistant casing and the rotation of the drive shaft or/and the rotation transmission mechanism can be performed individually or simultaneously while maintaining the vacuum inside the pressure-resistant tank. 
         [0013]    According to the present invention, therefore, a rotation surface treatment operation and a vertical movement surface treatment operation are simultaneously or individually performed while maintaining the vacuum inside the pressure-resistant tank, thereby expanding application of a surface treatment method in the vacuum and further enhancing a surface treatment effect. For example, a washing effect can be further enhanced by an increase in physical force in the washing operation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a cross-sectional view illustrating a surface treatment equipment according to a first embodiment of the present invention; 
           [0015]      FIG. 2  is an enlarged cross-sectional view partially illustrating the surface treatment equipment of  FIG. 1 ; 
           [0016]      FIG. 3  is a cross-sectional view illustrating the surface treatment equipment of  FIG. 1  in a state that a cylinder rod is moved upwardly; 
           [0017]      FIG. 4  is a cross-sectional view illustrating a surface treatment equipment according to a second embodiment of the present invention; 
           [0018]      FIG. 5  is a cross-sectional view illustrating a surface treatment equipment according to a third embodiment of the present invention; 
           [0019]      FIG. 6  is another cross-sectional view illustrating a surface treatment equipment according to a fourth embodiment of the present invention; and 
           [0020]      FIG. 7  is a cross-sectional view illustrating the surface treatment equipment taken along the line A-A of  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Embodiment 1 
       [0021]    A detailed description is given of a first embodiment of the present invention with reference to  FIG. 1  through  FIG. 3 . As illustrated in  FIG. 1 , a reference numeral “ 1 ” represents a pressure-resistant tank. An opening  4  is disposed to a top board  2  of the pressure-resistant tank  1 , and a cover  5  is disposed on the opening  4  through which a surface treatment cage  3  is passable. A sealing member  6  having soft elasticity is disposed to a bottom surface of the cover  5  or an upper portion of the top board  2 . The sealing member  6  allows space between the opening  4  and the cover  5  to be sealable in a case where the pressure inside the pressure-resistant tank  1  is reduced. 
         [0022]    An insertion opening  8  is disposed to the top board  2  of the pressure-resistant tank  1  and allows a pressure-resistant casing  7  having a cylindrical shape to be insertable therethrough. The pressure-resistant casing  7  is inserted through the insertion opening  8 , and a lower end thereof is slidably disposed inside the pressure-resistant tank  1 . The pressure-resistant casing  7  includes a top wall  11  and a bottom wall  12  respectively disposed to an upper end and a lower end of a peripheral wall  10  having a cylindrical shape, and an upper end side thereof is protruded outwardly from the pressure-resistant tank  1 . 
         [0023]    A drive shaft  13  is penetratingly disposed to the pressure-resistant casing  7  in such a manner as to be rotatable and not to be vertically slidable. That is, each of the top wall  11  and the bottom wall  12  of the pressure-resistant casing  7  includes an insertion hole  14  allowing the drive shaft  13  to be insertable therethrough, and the drive shaft  13  is inserted into the insertion holes  14  through bearings  15 . An upper end and a lower end of the drive shaft  13  penetrate outwardly from the respective top wall  11  and bottom wall  12  of the pressure-resistant casing  7 . 
         [0024]    A rotation drive mechanism  16  including an electric motor to rotate the drive shaft  13  is disposed to the upper end of the drive shaft  13 . In the pressure-resistant casing  7 , a protrusion portion  17  protruded outwardly from the pressure-resistant tank  1  is connected with a vertical movement mechanism  18  allowing the pressure-resistant casing  7  to make a vertical movement. The vertical movement mechanism  18  is a hydraulic cylinder  20 , and a cylinder rod  21  of the hydraulic cylinder  20  is connectively secured to the protrusion portion  17  of the pressure-resistant casing  7  through a connection member  22 . 
         [0025]    The vertical movement mechanism  18  is operated to vertically move the cylinder rod  21 , so that the pressure-resistant casing  7  is allowed to make the vertical movement. Such a vertical movement of the pressure-resistant casing  7  allows the drive shaft  13  to make a vertical movement. Herein, the hydraulic cylinder  20  serves as the vertical movement mechanism  18  according to the embodiment. However, a pneumatic cylinder, a screw, or a chain block, and the like may be used as the vertical movement mechanism in a different embodiment. A support board  23  is protrusively disposed to the bottom wall  12  of the pressure-resistant casing  7  in a horizontal direction. 
         [0026]    The lower end of the drive shaft  13  is connected with a rotation transmission mechanism  24 . Herein, the rotation transmission mechanism  24  is described in detail. The rotation transmission mechanism  24  includes a drive rotation transmission gear  25  formed of a bevel gear disposed to the lower end of the drive shaft  13 . The drive rotation transmission gear  25  is engaged with a driven rotation transmission gear  27  formed of a bevel gear of a first driven shaft  26 . The first driven shaft  26  is rotatably disposed to a pair of first support arms  28  in a horizontal direction, and the first support arms  28  are protrusively disposed to a bottom surface of the support board  23 . The driven rotation transmission gear  27  is disposed to one end of the first driven shaft  26  on the side close to the drive shaft  13 . A first sprocket  29  is disposed to another end of the first driven shaft  26 . 
         [0027]    A second sprocket  31  disposed to one end of a second driven shaft  30  is disposed above the first sprocket  29  of the first drive shaft  13  through the support board  23 . The second driven shaft  30  is rotatably disposed in the horizontal direction and to a pair of second support arms  32  standing on an upper surface of the support board  23 . The second driven shaft  30  allows the second sprocket  31  of the second driven shaft  30  and the first sprocket  29  of the first driven shaft  26  to be coupled by a rotation transmission chain  33 . 
         [0028]    The rotation transmission mechanism  24  is connected with a working mechanism  34  transmitting the driving force of the drive shaft  13  through the rotation transmission mechanism  24  and performing the surface treatment operation. The working mechanism  34  allows a pair of rotation transmission rollers  35  to be secured to outer circumference of the second driven shaft  30  with an interval between the rotation transmission rollers  35 , and is formed by placing the surface treatment cage  3  on the pair of rotation transmission rollers  35 . The surface treatment cage  3  is rotated by rotation of the rotation transmission rollers  35 , thereby performing the surface treatment operation on the object to be processed placed inside the surface treatment cage  3 . For example, the surface treatment cage  3  serves as a cage storing the object to be washed and is used as a washing equipment for the object to be washed. 
         [0029]    As illustrated in  FIG. 2 , an annular pressure-resistant portion housing  37  having an annular pressure-resistant vacuum sealing member  36  disposed thereinside is closely secured along the insertion opening  8  in an outer circumferential position of the pressure-resistant casing  7  on an upper surface of the pressure-resistant tank  1 . An inner circumferential surface and an outer circumferential surface of the pressure-resistant vacuum sealing member  36  disposed inside the pressure-resistant housing  37  are respectively disposed to an outer circumferential surface of the pressure-resistant casing  7  and an inner circumferential surface of pressure-resistant housing  37  in a close contact manner, so that the outside air communication portion between the pressure-resistant tank  1  and the pressure-resistant casing  7  is sealed, thereby maintaining the air-tightness inside the pressure-resistant tank  1  in the outside air communication portion. The pressure-resistant vacuum sealing member  36  maintains the air-tightness in response to the vertical movement of the pressure-resistant casing  7 . The pressure-resistant vacuum sealing member  36  does not necessarily respond to a rotation portion (described later), thereby having a light load and capable of stably maintaining the air-tightness for a prolonged period. 
         [0030]    As illustrated in  FIG. 1 , annular drive portion housings  38  are closely secured to respective top and bottom surfaces of the pressure-resistant casing  7  along the insertion holes  14 , and are disposed to the outer circumference of the drive shaft  13  in the pressure-resistant casing  7 . As illustrated in  FIG. 1  and  FIG. 2 , annular drive vacuum sealing members  40  are disposed inside the drive portion housings  38 . An inner circumferential surface and an outer circumferential surface of each of the drive vacuum sealing members  40  are respectively disposed to the outer circumferential surface of the drive shaft  13  and the inner circumferential surface of the drive portion housing  38  in a close contact manner, so that the outside air communication portions between the pressure-resistant casing  7  and the drive shaft  13  are sealed, thereby maintaining the air-tightness inside the pressure-resistant tank  1  in the outside air communication portions. Since the drive shaft  13  does not make any vertical movement relative to the pressure-resistant casing  7 , the drive vacuum sealing members  40  can maintain the air-tightness in response only to the rotation of the drive shaft  13  and do not necessarily respond to the vertical movement, thereby having a light load and capable of stably maintaining the air-tightness for a prolonged period. 
         [0031]    According to the embodiment described above, the drive vacuum sealing members  40  are disposed to the respective top and bottom surfaces of the pressure-resistant casing  7 , thereby stably maintaining high air-tightness. However, the drive vacuum sealing member  40  may be disposed to one of the top or bottom surfaces of the pressure-resistant casing  7  in a different embodiment. Consequently, a sealing effect may be obtained at a low cost. 
         [0032]    A description is now given of the washing operation in the vacuum atmosphere in a case where the surface treatment cage  3  is used as a washing cage for the object to be washed according to the above structure. The cover  5  of the pressure-resistant tank  1  is removed, and the vertical movement mechanism  18  is operated to upwardly move the cylinder rod  21  of the hydraulic cylinder  20  and the pressure-resistant casing  7 , so that the second driven shaft  30  is disposed to the opening  4  as illustrated in  FIG. 3 . The surface treatment cage  3 , serving as the washing cage, having the object to be washed stored thereinside is placed on the rotation transmission rollers  35  of the second driven shaft  30 . 
         [0033]    Subsequently, the vertical movement mechanism  18  is operated to downwardly move the cylinder rod  21  and the pressure-resistant casing  7 , so that the surface treatment cage  3  is disposed inside the pressure-resistant tank  1 . Next, washing solution is imported inside the pressure-resistant tank  1 . Herein, the opening  4  of the pressure-resistant tank  1  is covered with the cover  5  and is sealed as illustrated in  FIG. 1 , and the pressure-resistant tank  1  reduces the pressure thereinside by operation of a pressure reduction mechanism (not shown). 
         [0034]    Herein, the outside air communication portion between the pressure-resistant tank  1  and the pressure-resistant casing  7  is sealed by the pressure-resistant vacuum sealing member  36  as described above, and the outside air communication portions between the pressure-resistant casing  7  and the drive shaft  13  have been sealed, thereby allowing the inside of the pressure-resistant tank  1  to be in the vacuum. The pressure-resistant tank  1  maintains the vacuum thereinside, so that the washing solution is deaerated. For example, in a case where an ultrasonic oscillator  54  is disposed to a bottom portion of the pressure-resistant tank, and ultrasonic cleaning is performed, not only the ultrasonic wave is less attenuated compared to a case of performing the ultrasonic cleaning at the normal pressure, but also a washing effect can be enhanced by exhausting the air adhered to a small undulated area of the object to be washed to have good contact with the washing solution. 
         [0035]    Accordingly, the rotation drive mechanism  16  is operated to rotate the drive shaft  13 , so that the first driven shaft  26  is rotated through the drive rotation transmission gear  25  and the driven rotation transmission gear  27 . The rotation of the first driven shaft  26  allows the first sprocket  29  of the first driven shaft  26  to rotate, so that the second sprocket  31  of the second driven shaft  30  is rotated through the rotation transmission chain  33 . Therefore, the second driven shaft  30  is rotated in the same direction as the first driven shaft  26 , and the pair of rotation transmission rollers  35  disposed to the second driven shaft  30  is rotated. 
         [0036]    The rotation of the rotation transmission rollers  35  allows the surface treatment cage  3  serving as the washing cage to rotate, thereby performing the washing operation on the object to be washed in the surface treatment cage  3 . Therefore, in a case where the drive shaft  13  is rotated, the outside air communication portions between the pressure-resistant casing  7  and the drive shaft  13  are sealed by the drive vacuum sealing members  40 , thereby maintaining the vacuum inside the pressure-resistant tank  1 . Since the drive shaft  13  does not make the vertical movement relative to the pressure-resistant casing  7 , the drive vacuum sealing members  40  can maintain the air-tightness in response only to the rotation of the drive shaft  13  and do not necessarily respond to the vertical movement of the pressure-resistant casing  7 , thereby having a light load and capable of stably maintaining the air-tightness for a prolonged period. 
         [0037]    Moreover, the vertical movement mechanism  18  is operated to move the cylinder rod  21  up and down, so that the support board  23  vertically moves with the pressure-resistant casing  7 . The surface treatment cage  3  disposed above the support board  23  vertically moves with the vertical movement of the support board  23 , and the surface treatment operation is performed on the object to be processed by the vertical movement of the surface treatment cage  3 . In a case where the pressure-resistant casing  7  makes the vertical movement, the outside air communication portion between the pressure-resistant tank  1  and the pressure-resistant casing  7  is sealed by the pressure-resistant vacuum sealing member  36 , thereby maintaining the vacuum inside the pressure-resistant tank  1 . The pressure-resistant vacuum sealing member  36  maintains the air-tightness in response only to the vertical movement of the pressure-resistant casing  7  and does not necessarily respond to the rotation of the drive shaft  13 , thereby having a light load and capable of stably maintaining the air-tightness for a prolonged period. 
         [0038]    Moreover, in a case where the drive shaft  13  is rotated inside the pressure-resistant tank  1  in the vacuum as described above, the pressure-resistant tank  1  maintains the vacuum thereinside using the drive vacuum sealing members  40 . In a case where the pressure-resistant casing  7  makes the vertical movement inside the pressure-resistant tank  1  in the vacuum as described above, the pressure-resistant tank  1  maintains the vacuum thereinside using the pressure-resistant vacuum sealing member  36 . Therefore, the rotation surface treatment operation and the vertical movement surface treatment operation can be performed individually. Moreover, in a case where the drive shaft  13  is rotated at the same time as the vertical movement of the drive shaft  13  made by the vertical movement of the pressure-resistant casing  7 , the rotation surface treatment operation and the vertical movement surface treatment operation can be performed simultaneously. In a case where the rotation surface treatment operation and the vertical movement surface treatment operation are simultaneously performed, the surface treatment effect can be further enhanced. For example, the washing effect can be further enhanced by an increase in physical power in the washing operation. 
       Embodiment 2 
       [0039]    According to the first embodiment described above, the drive vacuum sealing members  40  are disposed to the respective top wall  11  and bottom wall  12  of the pressure-resistant casing  7 . According to a second embodiment, on the other hand, a pressure-resistant storage unit  41  storing a rotation transmission mechanism  24  therein is disposed in a lower end of a pressure-resistant casing  7 , and a drive vacuum sealing member  40  is disposed to the pressure-resistant storage unit  41 . A detailed description is given of the second embodiment with reference to  FIG. 4 . The pressure-resistant storage unit  41  stores therein a drive rotation transmission gear  25  of a drive shaft  13 , a driven rotation transmission gear  27  of a first driven shaft  26 , the first driven shaft  26 , a first sprocket  29  of the first driven shaft  26 , and a second sprocket  31  of a second driven shaft  30 , and is disposed to the lower end of the pressure-resistant casing  7 . 
         [0040]    The second driven shaft  30  including the second sprocket  31  is disposed in a horizontal direction and protrudes outward from an insertion hole  42  of the pressure-resistant storage unit  41 . A support board  23  protruding from the pressure-resistant storage unit  41  is disposed below the second driven shaft  30 , and a working mechanism  34  formed substantially the same as the first embodiment is disposed to the support board  23 . 
         [0041]    In the pressure-resistant storage unit  41  as illustrated in  FIG. 4 , a drive portion housing  38  having the drive vacuum sealing member  40  disposed thereinside is closely secured to outer circumference of the insertion hole  42 , and such a drive portion housing  38  is disposed to outer circumference of the second driven shaft  30 . The drive vacuum sealing member  40  disposed inside the drive portion housing  38  is disposed between an inner circumference of the drive portion housing  38  and the outer circumference of the second driven shaft  30 , so that an outside air communication portion between the pressure-resistant casing  7  and the rotation transmission mechanism  24  is sealed, thereby capable of maintaining air-tightness inside the pressure-resistant tank  1  in the outside air communication portion. 
         [0042]    The drive vacuum sealing member  40  can maintain the air-tightness in response only to the rotation of the rotation transmission mechanism  24 , and does not necessarily respond to the vertical movement of the pressure-resistant casing  7 , thereby having a light load and capable of stably maintaining the air-tightness for a prolonged period. According to the second embodiment, therefore, in a case where the pressure-resistant casing  7  makes the vertical movement, and in a case where the drive shaft  13  is rotated, the pressure-resistant tank  1  can maintain the vacuum thereinside using a pressure-resistant vacuum sealing member  36  and the drive vacuum sealing member  40 , respectively, as similar to the above first embodiment. Therefore, the rotation surface treatment operation and the vertical movement surface treatment operation can be performed individually or simultaneously in the vacuum. 
       Embodiment 3 
       [0043]    According to the first embodiment described above, the surface treatment cage  3  is disposed in the horizontal direction and is rotatable around a horizontal axis by the rotation transmission mechanism  24 . According to a third embodiment, on the other hand, a surface treatment cage  3  is disposed in a perpendicular direction and is rotatable around a perpendicular axis by a rotation transmission mechanism  24 . A detailed description is given of the third embodiment with reference to  FIG. 5 . A first driven shaft  26  is disposed below a support board  23  in a horizontal direction, and a pair of driven rotation transmission gears  43 ,  44  formed of bevel gears is disposed to respective ends of the first driven shaft  26 . The driven rotation transmission gear  43  is engaged with a drive rotation transmission gear  25  of the first driven shaft  26  while the driven rotation transmission gear  44  is engaged with a second driven rotation transmission gear  45  disposed below a second driven shaft  30 . The second driven shaft  30  is rotatably disposed to and inserted into the support board  23  in the perpendicular direction, and a bearing  46  is interposed between the second driven shaft  30  and the support board  23 . A rotation table  47  having a disk shape is disposed to an upper end of the second driven shaft  30 , and the surface treatment cage  3  is securely disposed on an upper surface of the rotation table  47  in the perpendicular direction. 
         [0044]    Therefore, a rotation drive mechanism  16  is operated to rotate the drive shaft  13 , so that the second driven shaft  30  is rotated through the first driven shaft  26 . The rotation of the second driven shaft  30  allows the surface treatment cage  3  to rotate around the perpendicular axis with the rotation table  47 . 
         [0045]    In a case where the drive shaft  13  is rotated, an outside air communication portion between the pressure-resistant casing  7  and the drive shaft  13  is sealed by a drive vacuum sealing member  40 , thereby capable of maintaining the air-tightness inside the pressure-resistant tank  1 . Therefore, the rotation of the drive shaft  13  allows the surface treatment cage  3  to rotate around the perpendicular axis in a vacuum. Since the drive shaft  13  does not make a vertical movement relative to the pressure-resistant casing  7 , the drive vacuum sealing member  40  can maintain the air-tightness in response only to the rotation of the drive shaft  13  and does not necessarily respond to the vertical movement of the pressure-resistant casing  7 , thereby having a light load and capable of stably maintaining the air-tightness for a prolonged period. 
       Embodiment 4 
       [0046]    According to the first and second embodiments described above, the rotation transmission rollers  35  are disposed to the second driven shaft  30 , and the surface treatment cage  3  is placed on the rotation transmission rollers  35 , so that the surface treatment cage  3  can be rotated by the rotation of the rotation transmission rollers  35 . According to a fourth embodiment, on the other hand, a transfer chain  48  is disposed to a second driven shaft  30 , and a surface treatment cage  3  is placed on the transfer chain  48 , so that the surface treatment cage  3  is oscillatable in a horizontal direction. 
         [0047]    A detailed description is now given of the fourth embodiment with reference to  FIG. 6  and  FIG. 7 . The second driven shaft  30  includes a pair of transfer sprockets  50  disposed thereto. As illustrated in  FIG. 7 , an auxiliary shaft  51  is disposed parallel to the second driven shaft  30  above a support board  23 . As similar to the driven shaft  30 , the auxiliary shaft  51  includes a pair of transfer sprockets  52  disposed thereto. The transfer sprockets  50  of the second driven shaft  30  and the transfer sprockets  52  of the auxiliary shaft  51  are coupled by a respective pair of transfer chains  48 . 
         [0048]    As illustrated in  FIG. 6 , the surface treatment cage  3  is placed on the pair of transfer chains  48 , and a rotation drive mechanism  16  is operated to rotate the drive shaft  13  little by little in an opposite direction. Accordingly, the transfer chains  48  are rotated little by little in the opposite direction through the first and second driven shafts  26  and  30 , so that the surface treatment cage  3  oscillates in the horizontal direction. Therefore, the surface treatment operation is performed on an object to be processed inside the surface treatment cage  3  by oscillating the surface treatment cage  3 . 
         [0049]    In a case where the drive shaft  13  is rotated, an outside air communication portion between the pressure-resistant casing  7  and the drive shaft  13  is sealed by a drive vacuum sealing member  40 , thereby capable of maintaining the air-tightness inside the pressure-resistant tank  1 . The rotation of the drive shaft  13  allows the surface treatment cage  3  to oscillate in the vacuum. Since the drive shaft  13  does not make the vertical movement relative to the pressure-resistant casing  7 , the drive vacuum sealing member  40  can maintain the air-tightness in response only to the rotation of the drive shaft  13  and does not necessarily respond to the vertical movement of the pressure-resistant casing  7 , thereby having a light load and capable of stably maintaining the air-tightness for a prolonged period. 
         [0050]    According to the fourth embodiment, in a case where the pressure-resistant casing  7  makes the vertical movement, and in a case where the drive shaft  13  is rotated, the pressure-resistant tank  1  can maintains the vacuum thereinside using a pressure-resistant vacuum sealing member  36  and the drive vacuum sealing member  40 , respectively, as similar to the above first and second embodiments. Therefore, the rotation surface treatment operation and the vertical movement surface treatment operation can be performed individually or simultaneously in the vacuum.