JP4284118B2 - Substrate transfer device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate transfer apparatus, and more particularly, to a single arm substrate transfer apparatus that can efficiently transfer a large liquid crystal substrate or the like in a compact transfer space under high vacuum and high temperature conditions.
[0002]
[Prior art]
Currently, vacuum and high-temperature processes occupy an important position in the manufacturing process of semiconductor and liquid crystal substrate products. Among them, the conveyance of workpieces such as substrates in a vacuum atmosphere is extremely important in the equipment configuration. Yes.
[0003]
In the field of manufacturing liquid crystal substrates, it is important to increase the production volume by increasing the work size and reduce the cost, and the need for larger substrates is increasing. With the increase in size of such a substrate, it is necessary to cope with the form of a transfer device in a vacuum to achieve high accuracy and high efficiency. For example, in manufacturing a liquid crystal substrate or the like of 1000 mm □ or less, a twin-arm structure transfer device has been proposed in which two arms are linked and can transfer two substrates simultaneously in a predetermined sequence (for example, Patent Documents). 1, refer to Patent Document 2.) In these devices, a belt drive system is used in which the twin arms are each configured to achieve predetermined arm rotation via a pulley having a rubber belt, a steel wire, and a chain attached to a rotation shaft. ing.
[0004]
[Patent Document 1]
Japanese Patent No. 2580489.
[Patent Document 2]
Japanese Patent Laid-Open No. 10-163296.
[0005]
[Problems to be solved by the invention]
However, in the case of transporting a large substrate of about 1000 mm x 1000 mm □, in addition to the fundamental problem that the arm swivel range must be secured as the work size increases, the transport distance is increased. There is a possibility that the arm may bend due to the lack of rigidity of the arm driving mechanism due to the increase in length, or the conveyance path may meander.
[0006]
Further, in the above-described transfer device, outgas that inhibits a high vacuum state is generated in the rubber belt. Since a steel belt or a wire is repeatedly bent when it is wound around a pulley, there is a risk that fatigue failure will occur early. Furthermore, since the rotational angle of the rotary shaft is controlled at a predetermined diameter ratio, a large-diameter pulley may be required, and it is difficult to reduce the mechanism. In addition, when a substrate or the like is processed under high temperature processing conditions, there is a problem in terms of durability because the belt and the wire are deformed and deteriorated at an early stage.
[0007]
In order to solve these problems, the applicant has developed a substrate transfer device having a twin arm structure (see Japanese Patent Application No. 2003-119266). Since this twin arm structure has a parallel link mechanism built into the arm body, excellent durability can be expected even in harsh usage environments. The structural advantage can be exhibited even in a single arm structure.
[0008]
SUMMARY OF THE INVENTION An object of the present invention is to provide a substrate transport apparatus having a single arm structure that can be used in a high temperature and high vacuum state, capable of accurately transporting a large substrate in a compact space, and having high durability. It is to provide.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is pivotally supported at the first rotational drive shaft ends of two rotational drive shafts supported concentrically and supported by a fixed portion, and has a second rotational drive shaft inside. A first parallel link that can be deformed by an input from one side, a two-arm crank that has one arm that is a short side on the output side of the first parallel link, and that can rotate integrally around a common rotation support shaft; The other arm of the arm crank is a short side on the input side, and is pivotally supported by the swivel arm in which the intermediate parallel link that deforms following the deformation of the first parallel link is accommodated in the casing, and the shared rotation support shaft, A second swivel member that has a linear guide that swivels around the common support shaft and that allows the slider to travel linearly with deformation of the first parallel link, and a second that can be deformed by the rotation transmitted from the intermediate parallel link in the swivel arm. have a parallel link in the casing , The hand is provided on the output side shaft of the second parallel link, connecting the arm body pivot by the pivot member is applied, and the one end of the shaft end shaft and the pivot arm of said arm body in the vertical A solid shaft provided with an arm turning lever for supporting the slider, a lower side of the short side member of the intermediate parallel link in the turning arm, and an upper side of the input side of the second parallel link in the arm body. A rotating support shaft that is coaxially configured with a hollow shaft portion that is a side member and is formed with a synchronous crank positioned above and below, and the swivel member around the shared support shaft by swiveling of the swivel arm A predetermined turning angle is given to the arm main body according to the turning angle of the arm turning lever that follows the linear travel of the slider according to the turning of the slider, and the hand during turning is deformed by the deformation of the second parallel link. Wherein the conveying direction is maintained.
[0010]
An isosceles triangular link formed by the intermediate parallel link and the arm turning lever that deforms the first parallel link and the intermediate parallel link by fixing the second rotation drive shaft during the turning of the turning arm. the angle of the vertex of, varied to follow the straight running of the slider, with respect to the pivot angle θ of the swivel arm, the turning angle 2θ is to be applied to the pivot member for pivoting said arm body It is preferable.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a substrate transfer apparatus of the present invention will be described with reference to the accompanying drawings.
[Common drive unit]
FIG. 1 is a front cross-sectional view for explaining the mechanism configuration of each part of the substrate transfer apparatus. The substrate transfer apparatus 1 is supported by the fixing unit 2 via the base plate 3 and is installed so that the entire arm is located in the vacuum atmosphere 4. Two rotation drive shafts R ₁ and R _{2 that} are concentrically arranged around the central axis O and can be independently driven to rotate are fixed to the base plate 3 via bearings.
[0013]
These rotary drive shafts R ₁ and R ₂ are a solid rotary drive shaft R _2, and the solid rotary drive shaft R ₂ is rotatably supported by a ball bearing (not shown) and is independently driven to rotate. is composed of a hollow cylindrical rotary drive shaft R ₁ Prefecture possible rotation angle by the rotation control unit (not shown), the rotational angular velocity, the rotational direction is controlled with high precision. Further, when this apparatus is used in a vacuum atmosphere, it is preferable to attach a vacuum seal to the rotary drive shafts R ₁ and R ₂ to partition the vacuum atmosphere from the atmospheric atmosphere.
[0014]
A swivel arm 10 is fixed to the upper end of the hollow cylindrical rotary shaft R ₁ supported by the base plate 3. The swivel arm 10 is composed of an elongated oval arm as shown in the plan views of FIGS. 2 and 4, and swivels around the central axis O as the hollow cylindrical rotary shaft R ₁ is driven to rotate. The arm body 11 is connected to the other end (free end) of the swivel arm 10 via a solid rotating shaft 111S. The arm body 11 can be swung around the solid rotating shaft 111S at a swivel angle 2θ in conjunction with the swivel angle θ of the swivel arm 10, and is mounted on the fork 13 of the hand 12 connected to the free end side of the arm body 11. The placed substrate P can be conveyed linearly in a predetermined direction (see FIGS. 7 and 8).
[0015]
[Configuration of swivel arm]
The swivel arm 10 is a stainless steel hollow box-shaped member as shown in FIG. 2, and a solid rotation shaft 111 </ b> S for swiveling the arm main body 11 is rotated inside the swivel arm 10 by a predetermined angle. A link mechanism for rotating the synchronous crank 105 that holds the direction of the hand connected to the end by a predetermined angle is accommodated.
Hereinafter, the first parallel link, the intermediate parallel link, and the solid rotation shaft, the hollow rotation shaft, and the synchronous crank which are the output side of these link mechanisms will be described which are configured by the respective members accommodated in the turning arm 10.
[0016]
(Configuration of the first parallel link)
A solid rotary shaft R ₂ supported by a ball bearing (not shown) is disposed in the inner space of the hollow cylindrical rotary shaft R ₁ . Among the upper end of the actual rotation axis R _2, as shown in FIG. 2, the drive input crank 101 is fixed. At the free end of the drive input crank 101, as shown in FIG. 2, the long arm 102 constituting the first parallel link 110 that is deformed as each crank rotates can be rotated via the connection node A. Further, a two-arm crank 103 that is rotatable around the rotation support shaft C is connected to the connection node B at the other end of the long arm 102, thereby connecting the rotation drive shaft central axis O and the rotation support shaft C. A first parallel link 110 (OABC) having a side as a fixed side is formed.
[0017]
(Configuration of intermediate parallel link)
Further, as shown in FIG. 3, the short arm 104 is connected via the connection node D at the other end of the both-arm crank 103, and the other end of the short arm 104 is the synchronous crank that holds the direction of the hand 12 described above. It is connected to the free end of 105 through a connection node E. As a result, an intermediate parallel link 100 (FEDC) is formed in which the side connecting the rotation support shaft F and the rotation support shaft C is a fixed side. As shown in FIGS. 2 and 3, the intermediate parallel link 100 uses the first parallel link 110 and the both-arms crank 103 as a common member, so that the first parallel link 100 is driven by the rotational driving force input from the drive input crank 101. The link 110 is deformed, and the intermediate parallel link 100 is deformed via the both arm cranks 103 following the deformation.
[0018]
(Configuration of solid rotating shaft, hollow rotating shaft and synchronous crank)
The rotation support shaft F is composed of a solid rotation shaft 111S and a hollow cylindrical rotation shaft 125S which are coaxially arranged and can be independently rotated in terms of the member configuration, and of these, the upper and lower ends of the hollow cylindrical rotation shaft 125S are respectively provided on the upper and lower ends. Synchronous cranks (105, 125) are integrally formed. As shown in FIGS. 1, 3 and 5, these synchronous cranks are formed in the same shape and in the same direction so as to connect another link to the free end. On the other hand, an arm turning lever 111 is formed at the lower end of the solid rotating shaft 111S, and the upper end passes through the upper end of the casing of the arm body 11 and is fixed to the arm body 11, and the arm rotates according to the rotation angle of the arm turning lever 111. The main body 11 can be turned.
[0019]
[Configuration of arm body]
The arm body 11 is a stainless steel hollow box-like member similar to the revolving arm 10, and the inside of the arm body 11 is a substrate P (mounted on the fork 13 of the hand 12 connected to the free end side of each arm body 11. A second parallel link for transporting FIG. 8) by linear movement in a predetermined direction is accommodated. In the following, the structure of the second parallel link for maintaining the direction of conveyance of the revolving member and the hand 12 for giving a predetermined revolving angle will be described.
[0020]
(Structure of swivel member)
A turning member for turning the arm body 11 will be described with reference to FIGS. As described above, the arm body 11 turns to form a predetermined angle with respect to the turning arm 10 by the rotation of the solid rotation shaft 111S. As shown in FIGS. 4 and 6, the rotation of the solid rotation shaft 111 </ b> S is formed integrally with the lower end of the solid rotation shaft 111 </ b> S, and the turning operation of the arm turning lever 111 protruding from below the arm body 11. Realized by. The arm turning lever 111 turns as the L-shaped crank 113 having one end connected via a linear guide 114 rotates around the rotation support shaft C. That is, the free end of the lever 111 is connected to the slider 116 slidable along the rail 115 of the linear guide 114 attached to the side surface of the L-shaped crank 113 via the connection node G.
[0021]
As shown in FIGS. 1, 4, and 6, the swivel member including the L-shaped crank 113 is formed integrally with the lower end of the rotation support shaft C while the upper end of the rotation support shaft C. The two arms crank 103 are integrally formed. The rotation of the L-shaped crank 113 is realized as the both-arm crank 103 rotates around the rotation support shaft C as the first parallel link 110 is deformed. Details of the operation will be described later.
[0022]
(Configuration of the second parallel link)
Next, the structure of the 2nd parallel link 120 is demonstrated with reference to FIG.3, FIG.5, FIG.7. A hollow rotary shaft 125S that rotatably supports the lower synchronous crank 105 constituting one side of the intermediate parallel link 100 housed in the swivel arm 10 extends into the arm body 11, and is formed at the upper end of the hollow rotary shaft 125S. A synchronous crank 125 having the same shape as the synchronous crank 105 is fixed in the same direction. As shown in FIGS. 5 and 7, the long arm 121 is connected to the free end of the synchronous crank 125 via a connection node H, and the other end of the long arm 121 is connected to the hand holding crank 122 via the connection node I. Are connected. As shown in FIG. 1, the rotating shaft J side of the hand holding crank 122 protrudes downward at the tip, and the base of the hand 12 is fixed via the mounting boss 14. As a result, a second parallel link 120 (FHIJ) having one side FH that performs the same turning operation as the one side FE of the intermediate parallel link 100 housed in the turning arm 10 is formed.
[0023]
[Linkage mechanism]
With reference to FIG. 6, an example of turning the above-described linkage of the first parallel link, the intermediate parallel link, and the second parallel link will be described. In FIG. 6, for the sake of explanation, a link mechanism diagram of a first parallel link 110, an intermediate parallel link 100, a second parallel link 120, and an isosceles triangular link schematically shown in a diagram, an L-shaped crank 113, A lever 111 connected via a linear guide 114 is shown in an overlapping manner. In the figure, rotation support shafts C and F are fixed points in the swing arm, and the rotation support shaft F of the intermediate parallel link 100 and the rotation support shaft F that rotates the synchronous crank 125 of the second parallel link 120 rotate in common. It consists of a hollow rotating shaft 125S which is a shaft. In the display of the diagram, the link FE of the intermediate parallel link 100 and the link FH of the second parallel link 120 that are actually overlapped in the vertical position are shifted for the sake of clarity. Further, the link CF of the intermediate parallel link 100 and the lever length FG of the arm turning lever 111 are set to CF = FG, and an isosceles triangle ΔFCG link that forms the base CG is formed. The three parallel links configured as described above are deformed by the rotation of the drive input crank 101 of the first parallel link 110, and the first parallel link 110 is deformed so as to be integrated with the link BC of the first parallel link 110 ( The link CD of the intermediate parallel link 100 which is the both-arm crank 103) rotates by the same angle, and the intermediate parallel link 100 is deformed. At that time, the L-shaped crank 113 fixed to the lower end of the rotation support shaft C turns around the rotation support shaft C as the both-arm cranks 103 rotate. Along with this turning operation, the free end (connection node G) of the arm turning lever 111 slidable along the linear guide 114 changes the length of the base CG of the isosceles triangle according to the turning direction of the L-shaped crank 113. Slide to let it go. At this time, as will be described later, as the arm turning lever 111 turns, the rotation support shaft 111S rotates by a predetermined angle, and the arm main body 11 fixed to the upper end of the rotation shaft 111S rotates by the rotation angle. Thus, in this invention, rotation of the hollow box-shaped member represented by the shape of the arm main body can be realized by the output of the parallel link mechanism accommodated in the hollow box-shaped member. Thereby, since a drive part can be accommodated in a box-shaped member, it becomes possible to suppress generation | occurrence | production of the dust etc. accompanying arm operation | movement to the minimum.
[0024]
On the other hand, the link FH links FE and the second parallel link 120 intermediate the parallel link 100, is formed integrally with the shaft portion so as to be positioned vertically and the bottom and top of the hollow cylindrical rotating shaft 125S, each It is comprised by the synchronous crank 105,125 of the same shape as a short side member of a link . Therefore, the link FH of the second parallel link 120 can turn by the same angle as the link FE of the intermediate parallel link 100, and the second parallel link 120 can be deformed.
[0025]
[Synchronous swiveling operation of swivel arm and arm body]
Here, a state in which the arm main body of the substrate transfer apparatus of the present invention is swung in synchronization with the swiveling of the swivel arm 10 will be described with reference to FIG. FIG. 8A is a plan view showing an initial state of the substrate transfer apparatus. The virtual circle K shown in the figure shows an occupied plane when the swivel arm 10 is swung while the arm main body 11 is completely bent and the liquid crystal substrate is held. In this embodiment, the liquid crystal substrate The arm main body 11 and the hand 12 are set so as to be accommodated in a locus plane through which the corner portion of P passes. When the swivel arm 10 is swung in the θ direction in FIG. 8B from this state, the swivel arm 10 is deformed inside the swivel arm 10 by fixing the solid rotation drive shaft R _2. turning angle 2β in arm swinging lever 111 is given by the action of an isosceles triangle link intermediate parallel links 1 0 0, L-shaped crank 113 and arm swing lever 111 is configured, the arm body 11 is outwardly pivoting angle of 2β Swinged out. Further, by the linkage operation of the first parallel link 110, the intermediate parallel link 100, and the second parallel link 120 described above, the hand 12 has the swivel arm 10 and the arm main body 11 as shown in FIGS. 8 (b) to 8 (c). When turning, keep the extension direction and go straight. As a result, for example, the arm main body 11 can be deployed to the position of FIG. 8C rotated 180 ° from the angle formed with the initial swing arm 10 in a state where the swing arm 10 is rotated 90 °.
[0026]
FIGS. 9 and 10 are arm operation state diagrams in which link diagrams are overlapped to explain the turning operation of the turning arm 10 and the arm body 11 and the holding direction holding operation of the hand 12. FIG. 9A is an operation state explanatory view showing, in an enlarged manner, the rotation support shaft portion of the arm main body 11 in the initial state of FIG. At this time, it is assumed that the angle formed between the swing arm 10 and the arm body 11 is 2α. From this state, as shown in FIG. 5B, the L-shaped crank 113 turns about the rotation axis C by θ ₁ when the turning arm 10 turns about the rotation center axis O by the turning angle θ = θ _1. . As a result, the free end (the connection node G) of the arm turning lever 111 slides outward along the linear guide 114, and the base of the isosceles triangle (ΔFCG) composed of the rotation support shafts C and F and the connection node G. The angles (vertical angles) formed by the apexes (F) sandwiching (CG) are reduced by θ _1, respectively, and the isosceles triangle gradually becomes flat. As a result, the angle (<OCJ) formed between the swing arm 10 and the arm body 11 is narrowed by 2θ ₁ . That is, the arm body 11 turns around the rotation support shaft F by the turning angle ω = 2θ ₁ . Similarly, when the swing arm 10 is rotated by θ = α, ΔFCG is completely crushed and the vertex F is positioned on the base CG. At this time, as a result of the arm body 11 also turning at ω = 2α, the arm body 11 overlaps with the turning arm 10 so as to be in a straight line as shown in FIG. When the swivel arm 10 further swivels about the central axis O from this state to FIGS. 10C to 10E, the vertex angle of the isosceles triangle (ΔFCG) formed on the opposite side is further reduced. The character-shaped crank 113 overlaps at the vertical position so as to enter the lower side of the arm turning lever 111. As a result, as shown in FIGS. 10D and 10E, when the revolving arm 10 is revolved by a revolving angle θ = θ ₂ → β, the hand holding crank 122 of the arm main body 11 at that time is ω = 2θ ₂ → It turns by 2β and reaches the farthest position from the initial state position.
[0027]
[Synchronization of swivel movement of arm body and linear movement of hand]
As described above, the swivel arm 10 and the arm main body 11 perform the swivel operation in synchronization with each other. However, the hand 12 moves linearly so that the hand 12 always faces the transport direction when the arm main body 11 swivels as the swivel arm 10 turns. To do. The linear movement of the hand 12 will be described with reference to FIGS. 9 and 10 again. In the initial state (FIG. 9A), as shown in FIG. 6, the links CD and FE of the intermediate parallel link 100 and the links FH and JI of the second parallel link 120 are in a parallel relationship. As shown in FIGS. 9 to 10, the second parallel link 120 is also deformed following the deformation of the intermediate parallel link 100. As a result, the hand holding crank 122 that holds the hand 12 (see FIG. 7) can always move linearly in the same direction.
[0028]
Note that the length of the arm body of the single arm described above, the transport operation achieved by turning the arm, the distance, the shape of the attached hand, and the dimensions are determined by the size of the liquid crystal substrate to be transported and the transport distance. . Further, each bearing employs a dust-free rolling element such as a ball bearing, thereby minimizing rolling resistance and ensuring excellent positioning characteristics. Furthermore, it goes without saying that the vertical movement mechanism and the arm transfer sequence can be appropriately selected, added, and deleted according to the application and specifications.
[0029]
【The invention's effect】
As described above, according to the present invention, the operation of the single arm for transporting the large liquid crystal substrate is realized by adopting the link mechanism and the linear guide with sufficient rigidity, so that the high accuracy and quickness can be achieved. Substrate transport is possible, and an extremely low outgas characteristic can be achieved with respect to a transport device employing a rubber belt or the like, and the operation under high temperature and high vacuum is possible.
[Brief description of the drawings]
FIG. 1 is a front cross-sectional view showing an embodiment of a substrate transfer apparatus of the present invention.
FIG. 2 is a plan view showing the inside of a turning arm shown in FIG.
FIG. 3 is a partially enlarged plan view showing a first parallel link and an intermediate parallel link in an enlarged manner.
FIG. 4 is a plan view showing a positional relationship between a swing arm and an L-shaped crank of a swing member.
FIG. 5 is a plan view showing a second parallel link of the arm body.
FIG. 6 is a link configuration diagram schematically showing the linkage of an isosceles triangular link formed by a first parallel link, an intermediate parallel link, a second parallel link, and a turning member.
FIG. 7 is a plan view showing a second arm body and a hand connected to a second parallel link.
FIG. 8 is a state explanatory view showing a turning state of each arm and a straight operation state of the hand by the substrate transfer device.
FIG. 9 is a state explanatory view (No. 1) showing a turning state of each arm, a linear movement state of a hand, and an operation state of a turning member.
FIG. 10 is a state explanatory diagram (part 2) showing a turning state of each arm, a linear movement state of a hand, and an operation state of a turning member;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Substrate conveyance apparatus 2 Fixed part 10 Turning arm 11 Arm main body 12 Hand 100 Middle parallel link 101 Driving input crank 102 Long arm 103 Both arms crank 104 Short arm 105 Synchronous crank 125S Hollow rotating shaft 110 First parallel link 111 Arm turning lever 111S Solid rotation shaft 113 L-shaped crank 114 Linear guide 115 Rail 116 Slider 120 Second parallel link 121 Long arm 122 Hand holding crank rotation drive shaft R ₁ , R ₂

Claims (2)

A first parallel link that is pivotally supported at the first rotational drive shaft end of two rotational drive shafts that are supported by the fixed portion and arranged concentrically, and that can be deformed by input from the second rotational drive shaft. One arm is the short side on the output side of the first parallel link, and both arm cranks that can rotate integrally around the common rotation support shaft, and the other arm of the both arm cranks is the short side on the input side. A swivel arm that houses an intermediate parallel link that becomes a side and deforms following the deformation of the first parallel link in a casing ;
A swiveling member that is supported by the shared rotation support shaft and that rotates around the shared support shaft in accordance with the deformation of the first parallel link, and has a linear guide that allows the slider to travel linearly ;
The casing has a second parallel link that can be deformed by the rotation transmitted from the intermediate parallel link in the swivel arm, a hand is provided on the output side support shaft of the second parallel link, and the swivel member can be swung. The arm body to be given,
A solid shaft portion provided with an arm turning lever for supporting the slider by vertically connecting a shaft at one end of the arm body and a shaft at one end of the turning arm, and a lower side being an intermediate parallel link in the turning arm. A rotation support constructed coaxially with a hollow shaft portion on which the upper side is a short side member on the input side of the second parallel link in the arm body and the upper and lower synchronous cranks are formed. With a shaft,
A predetermined turning angle is given to the arm body according to the turning angle of the arm turning lever that follows the linear travel of the slider according to the turning of the turning member around the common support shaft by turning of the turning arm. In addition, the substrate transfer apparatus is characterized in that the transfer direction of the hand is maintained during turning by the deformation of the second parallel link . An isosceles triangular link formed by the intermediate parallel link and the arm turning lever that deforms the first parallel link and the intermediate parallel link by fixing the second rotation drive shaft during the turning of the turning arm. The turning angle 2θ is given to the turning member that turns the arm body with respect to the turning angle θ of the turning arm . The substrate transfer apparatus according to claim 1.

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