JP2000153994A - Elevation positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To position an elevatable table at a highly precise elevation without causing lopsided load while reducing the size and cost of a device. SOLUTION: This device includes a pair of down-slope blocks 41 (41L, 41R) having a driving means 30 for reversibly rotating a screw shaft 33 with the reversible rotation drive of a motor 31 to move a pair of slide blocks 36 (36L, 36R) nearer or farther away from the screw shaft 33 in the axial direction and having an elevation mechanism 40 mounted nearer or farther away from it together with the slide blocks 36 (36L, 36R) and a pair of up-slope blocks 43 (43L, 43R) having the respective slopes 43S corresponding to the respective slopes 41S of the down-slope blocks 41 (41L, 41R) and fixed to an elevatable table 20 so as not to be relatively movable to the axial direction. The motion of the down-slope blocks 41 to be moved nearer or farther away from it is exchangeable to the elevating motion of the up-slope blocks 43.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of mounting a lifting table on a base plate via a lifting mechanism, activating a driving means and operating the lifting mechanism, thereby enabling the lifting table to be raised and lowered and positioned at a set height position. The present invention relates to a lifting / lowering positioning device formed on a vehicle.

[0002]

2. Description of the Related Art Referring to FIG. 14, a conventional lifting / lowering positioning apparatus mounts a lifting / lowering table 20P on a base plate 10P via a lifting / lowering mechanism 40P, activates driving means 30P to operate the lifting / lowering mechanism 40P, and thereby moves the lifting / lowering table 20P. Is formed so that it can be moved up and down and positioned at a set height position.

That is, a left stationary guide member 92L and a right stationary guide member 92R are erected on the base plate 10P, and the left movable guide member 91L is mounted on the lifting table 20P.
And the right movable side guide member 91R are integrally fixed, and a linear motion bearing 94 is provided between the two members 92L, 91L, 92R, 91R.
An elevating guide mechanism 90 equipped with L, 93L, 94R, and 93R is provided to guide the elevating table 20P slidably in the vertical direction.

The driving means 30P includes a base plate 10P
(The bracket 31P), the motor 31P, bearings 15PL, 15PR attached to the
The motor 31P includes a screw shaft 33P connected to the motor 31P via a P, and a slide block 36P integral with a nut member 35P screwed to the screw shaft 33P. Can be reciprocated.

The lifting mechanism 40P has a lower inclined block 4 having an inclined surface 41PS and fixed to a slide block 36P.
1P and an inclined surface 43PS corresponding to the inclined surface 41PS.
And an upper inclined block 43P fixed to the lower surface side of the elevating table 20P, and converts the horizontal movement of the lower inclined block 41P into an elevating movement of the elevating table 20P whose horizontal position is restricted by the elevating guide mechanism 90. It is possible.

In such a conventional vertical positioning device, for example, a pulse signal corresponding to a fixed rotation angle corresponding to a set height position is applied to a driver (not shown) of a motor 31P composed of, for example, a stepping motor, and the motor 31P is rotated by the fixed rotation angle by one. Rotate in the direction. Then, the screw shaft 33P rotates in one direction, and the slide block 36P moves to the left (or
In the right direction, that is, in the axial direction of the screw shaft 33P, it is moved by a certain distance. Accordingly, the inclined surface 41PS of the lower inclined block 41P rises (falls) on the inclined surface 43PS of the upper inclined block 43P, so that the elevating table 20P can be moved up and down. For example, a magnified observation target portion of a precision electronic component can be focused on an electron microscope.

[0007]

The lifting mechanism 4
0P is configured to convert the axial movement of the lower inclined block 41P having one inclined surface 41PS into the elevating movement of the upper inclined block 43P having one inclined surface 43PS. Is provided, an eccentric load is generated when the elevating table 20P moves up and down. The occurrence of this eccentric load not only lowers the height positioning accuracy because the upper surface horizontality of the elevating table 20P is disturbed, but also deteriorates the three-dimensional attitude of the elevating table 20P, thereby deteriorating the attitude of the sample to be inspected on the elevating table. In other words, it is impossible to secure a suitable height position.

The corresponding one of the inclined surfaces 41PS, 4
Since 3PS is used, the inclination angle of each of the inclined surfaces 41PS and 43PS must be reduced in order to increase (decrease) the resolution of the height positioning (the minimum value of the set height position) of the elevation table 20P. . That is, an increase in the size in the axial direction is caused. On the other hand, if the resolution is fixed, the amount of movement of the lower inclined block 41P in the axial direction increases, so that the positioning speed decreases.

In addition, since the open-loop control applies a pulse signal corresponding to the set height position to the driver of the motor 31P, the positioning accuracy is low (for example, ± 3 to 5 μm).
m). Therefore, the applicant of the present invention aims at further improving the resolution and the positioning accuracy to achieve a high resolution (for example, 0.1 μm).
m), the closed-loop control using the height position detecting means was tried. However, due to the configuration of the lifting mechanism 40P and the lifting guide mechanism 90 that generate an eccentric load, the positioning accuracy is high despite the increase in size and cost of the apparatus. For example, ± 1 to 0.
It could not be increased to 7 μm or less. because,
The change in the attitude of the lifting table 20P due to the occurrence of the eccentric load and the change in the horizontality of the upper surface thereof are more relevant to the resolution (0.1 μm).
Because it is much larger. In addition, it is difficult to incorporate sophisticated height position detecting means, but it is difficult due to its structure. In other words, it is difficult and insignificant to introduce a high-resolution height position detecting means. In other words, no matter how rugged the lifting guide mechanism 90 is after having tolerate a further increase in size and cost, as long as the lifting mechanism 40P has a structure that generates an eccentric load, it has high resolution and high accuracy. (± 0.5 μm or less), it is difficult to achieve height positioning.

SUMMARY OF THE INVENTION It is an object of the present invention to raise and lower a lifting table with high resolution without generating an eccentric load, and to achieve high-precision height positioning while reducing the size and cost. It is to provide a positioning device.

[0011]

According to a first aspect of the present invention, a lifting table is mounted on a base plate via a lifting mechanism.
In a lifting / lowering positioning device formed to be able to raise and lower the lifting table and to be able to be positioned at a set height position by activating the driving means and operating the lifting mechanism, the driving means reversibly drives the screw shaft by reversible rotation driving of the motor. The pair of slide blocks are formed so as to be separated and approachable in the axial direction of the screw shaft by rotating, and the lifting mechanism is
A pair of lower inclined blocks mounted on the respective slide blocks so as to be able to be separated and approached together with the respective slide blocks, and the respective inclined surfaces correspond to the respective inclined surfaces of the respective lower inclined blocks, and are relatively immovable in the axial direction. An elevation positioning device including a pair of upper inclined blocks fixed to an elevation table, and configured to be able to convert a separation approaching movement of each lower inclined block into an elevation movement of each upper inclined block.

In this invention, for example, each of the inclined surfaces of the pair of lower inclined blocks rises inward from the outside in the axial direction of the screw shaft, and each of the inclined surfaces of the pair of upper inclined blocks is inclined downward. In the case where each of the blocks can be engaged with the corresponding inclined surface of the block from the outside, when the motor forming the driving means is driven to rotate the screw shaft in one direction, a pair of slide blocks are driven by the pair of slide blocks. Separated in the axial direction. That is, the pair of lower inclined blocks (inclined surfaces) are separated in the axial direction.

[0013] Then, since the upper inclined block is fixed to the elevating table so as to be relatively immovable in the axial direction, each inclined surface rises along each inclined surface of the corresponding lower inclined block. That is, the lifting table can be raised. The height (elevation) position of the elevating table is determined by the axial distance between the lower inclined blocks after separation, that is, the rotation angle of the motor.

Next, when the motor is driven to rotate the screw shaft in the other direction, the pair of slide blocks approach in the axial direction of the screw shaft. That is, a pair of lower inclined blocks (inclined surfaces) are made to approach each other in the axial direction. Then, each of the inclined surfaces of each upper inclined block descends along each inclined surface of the corresponding lower inclined block. That is, the lifting table can be lowered. In this case, the height (down) position of the lifting table is also determined by the distance between the approaching lower inclined blocks in the axial direction, that is, the rotation angle of the motor.

That is, converting the approaching movement of each lower inclined block into the ascending / descending movement of each upper inclined block.
That is, the unbalanced load at the time of vertical movement can be canceled mechanically. Accordingly, the lifting table can be moved up and down with high resolution without generating an eccentric load, and downsizing and cost reduction and highly accurate height positioning can be achieved.

Further, according to the present invention, the inclined surface of each of the upper inclined blocks and the corresponding inclined surface of each of the lower inclined blocks are guided by a linear bearing so as to be slidably guided in an inclined direction. Device.

In this invention, the inclined surface of each upper inclined block rises and descends in the inclined direction via the linear bearing while sliding with the corresponding inclined surface of each lower inclined block approaching apart. Therefore, in addition to achieving the same operation and effect as in the case of the first aspect of the present invention, a smoother lifting movement can be performed, so that the load on the driving means can be reduced, and the axial distance between the lower inclined blocks and the lifting table can be reduced. High accuracy and certainty can be ensured.

According to a third aspect of the present invention, a biasing force of a biasing means is applied between the base plate and the elevating table so that the inclined surfaces of the upper inclined blocks correspond to the inclined surfaces of the lower inclined blocks. This is a lifting / lowering positioning device formed so as to be able to be pressed.

According to this invention, the inclined surfaces of the upper inclined blocks on the side of the lifting table use the urging force of the urging means,
It is pressed against the corresponding inclined surface of each lower inclined block on the base plate side. That is, it is possible to eliminate the backlash of the lifting mechanism and the driving means while keeping the relative position of each corresponding inclined surface constant. Therefore, in addition to achieving the same operation and effect as in each of the first and second aspects of the present invention, positioning can be performed with even higher precision.

Further, the invention according to claim 4 includes a scale attached to one of the base plate and the elevation table, and a position detector attached to the other, and a height position of the elevation table with respect to the base plate. Is a height position detecting device which is provided with a height position detecting means capable of detecting the motor, and which is capable of feedback-controlling the motor using a detected height position signal output from the height position detecting means.

In this invention, when the elevating table moves up and down, for example, the scale on the elevating table side and the position detector on the base plate side move vertically. That is, the height position detecting means outputs the height position signal while detecting the height position of the lifting table. Thus, the rotation of the motor can be controlled in a closed loop using the detected height position signal as a feedback signal for the set height position signal.

Therefore, in addition to providing the same operation and effect as in each of the first to third aspects of the present invention, a remarkably high precision positioning can be achieved as compared with the case of the conventional example of the open control. I can do it.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. The lifting / lowering positioning device is shown in FIG.
As shown in FIG. 9, the driving means 30 reversibly rotates the screw shaft (33) by the reversible driving of the motor 31 to form the pair of slide blocks 36 so as to be separated and approachable in the axial direction of the screw shaft (33). At the same time, a pair of lower inclined blocks 41 in which the elevating mechanism 40 is mounted so as to be separated from and approachable with the respective slide blocks 36, and the respective inclined surfaces 43S
Corresponds to the inclined surface 41S of each lower inclined block 41, and includes a pair of upper inclined blocks 43 fixed to the elevating table 20 so as to be relatively immovable in the axial direction. Each upper inclined block 43
It is formed so that it can be converted into a vertical movement.

FIG. 1 is a plan view, FIG. 2 is a left side view,
FIG. 3 is a right side view, and FIG. 4 is a front view. FIG. 5 is a plan view for explaining a state in which the elevating table 20 is removed, FIG. 6 is a left side view based on an arrow AA in FIG.
8 is a right side sectional view based on the line of sight BB, and FIG.
FIG. 9 is a cross-sectional view taken along line DD in FIG. 8. In FIGS. 6, 7 and 8, FIG.
For convenience of explanation, the lifting table 20 is illustrated.

In FIG. 8, the lifting / lowering positioning device includes a lifting table 2 on a base plate 10 via a lifting mechanism 40.
0 is mounted, the drive means 30 is activated, and the lifting mechanism 40 is raised and lowered, so that the lifting table 20 can be raised and lowered and positioned at a set height.

The base plate 10 is parallel to the upper and lower surfaces.
For example, when placed on a surface plate, the upper surface is in a horizontal state. 5 and 8, the motor block 11 is fixed on the right side. In addition, this base plate 10
As shown in FIG. 7, a pair of linear bearing rails 12A and 12B are fixed around the axis of an openable / closable ball screw shaft 33 that forms a screw shaft described in detail below.

These linear bearing rails 12A and 12B have
Each pair of linear bearing moving blocks 13AL, 13AR, 1
3BL and 13BR are slidably mounted. Then, the left linear bearing moving blocks 13AL, 13 in FIG.
The slide block 36L is screwed to the BL, and the slide block 36R is screwed to the right linear bearing moving blocks 13AR, 13BR. That is, each slide block 36L, 36R is connected to the linear bearing rail 1
It is slidable in the longitudinal direction of 2A and 12B (the left-right direction in FIGS. 5 and 8), that is, in the axial direction of the ball screw shaft 33.

The drive means 30 comprises a motor 31 capable of reversible rotation drive and a ball screw shaft 33 connected via a coupling 32. The ball screw shaft 33 includes a ball screw bracket 15L, 1 fixed to the base plate 10.
5R is supported by bearings via bearings. Motor 31
Employs a stepping motor, but may adopt another type (for example, an ultrasonic motor, a servomotor, or the like).

Here, the left screw portion 33L and the right screw portion 33R of the screw shaft, that is, the ball screw shaft 33 shown in FIG.
It is formed on a reverse screw. Ball flanges 35L and 35R are screwed into the screw portions 33L and 33R, respectively, and the ball flanges 35L and 35R are mounted and fixed to the slide blocks 36L and 36R. Thus, when the ball screw 33 is reversibly rotated, the slide block 36 is rotated.
The L and 36R can be moved away from each other in the horizontal direction in FIGS.

The lifting mechanism 40 includes a slide block 36.
A pair of lower inclined blocks 41L and 41R fixed to L and 36R, respectively, and a pair of lower inclined blocks 41L and 41R fixed to the lower surface of the elevating table 20 so as not to be relatively movable in the axial direction of the screw shaft (33).
The pair of upper inclined blocks 43L and 43R is configured to be able to convert the separation approaching movement of each lower inclined block 41L and 41R into the vertical movement of each upper inclined block 43L and 43R.

That is, the lower inclined block 41L on the left side is provided with an inclined surface 41S which is inclined downward from the upper right to the lower left (from inside to outside) as shown in FIG. 8, and the lower inclined block 41R on the right side is provided from the upper left to the right. Down (from inside to outside)
An inclined surface 41S that is inclined toward is provided. Each of the inclined surfaces 41S, 41S has the same angle (4 in this embodiment).
5 degrees). Also, the respective inclined surfaces 43S, 43S of the left and right upper inclined blocks 43L, 43R fixed to the lower surface side of the lifting table 20 correspond to the respective inclined surfaces 41S, 41S.
(45 degrees).

In this embodiment, each upper inclined block 43
L, 43R and the corresponding inclined surfaces 41S, 41S of the lower inclined blocks 41L, 41R correspond to the linear bearing 4 composed of a cross roller guide shown in FIG.
5 is slidably guided in the inclined direction. While reducing the load on the driving means 30 and achieving smooth lifting and lowering movements,
This is for ensuring the correspondence between the axial interval between the lower inclined blocks 41L and 41R and the elevation position of the elevation table 20 with high accuracy and reliability.

That is, in FIG. 8, when the lower inclined blocks 41L and 41R (inclined surfaces 41S and 41S) are separated (approached) in the left-right direction, the upper inclined blocks 43L and 43R are separated.
Since the interval between R in the left and right direction is fixed, the inclined surfaces 43S, 43S rise (fall) along the inclined surfaces 41S, 41S. That is, the unbalanced load when the lifting table 20 is moved up and down can be offset. That is, since the uneven load is not generated and the upper surface of the lifting table 20 can be kept horizontal, the lifting table 20 can be maintained at a high resolution.
Can be moved up and down and high-precision positioning can be performed, and the robust, large-sized and high-cost conventional elevating guide mechanism 90 can be wiped out, so that a significant reduction in size and cost can be achieved.

Further, as shown in FIGS. 2 to 4, the base plate 10 (spring hook 18) and the lifting table 2
0 (spring hook 28) and the urging force of the four urging means (spring 25) provided between
To each of the upper inclined blocks 43L and 43L.
The inclined surfaces 43S, 43S (45A, 45B) of the R are attached to the corresponding inclined surfaces 41S, 41S of the lower inclined blocks 41L, 41R.
It is formed so that it can be pressed. Therefore, the driving means 3
Since the backlash of each part including the elevating means 40 can be removed, the positioning can be performed with higher precision.

Incidentally, the inclined surfaces 43S, 43S of the upper inclined blocks 43L, 43R of the lifting mechanism 40 and the corresponding inclined surfaces 41S, 41S of the lower inclined blocks 41L, 41R.
Is not limited to the above configuration. That is, the upper inclined blocks 43L, 43R (inclined surfaces 43S, 43S)
As long as the relative position in the left-right direction is fixed, for example, as shown in FIG.

The height position detecting means 50 is mounted between a scale (optical main scale) 51 mounted on the elevation table 20 side via the bracket 26 shown in FIG. 10 and the brackets 19L, 19R (see FIG. 4). And a position detector 52 including an optical sub-scale, which is capable of detecting the height position of the lifting table 20 with respect to the base plate 10 and outputting a detected height position signal f shown in FIG. In addition, 59 is a cover.

The height position detecting means 50 has a detection resolution of 0.1 μm or less. That is, in the conventional example (FIG. 14), since an eccentric load is generated in the driving means 30P and the elevating mechanism 40P, and this changes the attitude of the elevating table 20P and the horizontality of the upper surface thereof, the high-resolution height position detection is performed. Although it is difficult to install the means 50 due to its structure and there is no point in introducing it, it is understood that the device of the present invention can be introduced for the first time and the effect can be obtained.

The scale 51 is connected to the base plate 10.
The position detector 52 may be attached to the lifting table 20 side. However, if it is mounted as in this embodiment, it is easy to simplify the wiring between the position detector 52 on the stationary side (10) and the outside. Further, the height position detecting means 50 may use another detection method (for example, an electrostatic detection method).

In FIG. 11, the limit detecting means 60
Consists of a pair of upper and lower photo sensors 62U and 62L attached to the base plate 10 via a bracket 66, and a dog 65 attached to the elevating table 20 via a bracket 27. In this embodiment, the home position (home position) ) And stroke end can be detected. The scaled block 67 is for visually confirming the position of the lifting table 20.

The linear bearings 45A and 45B shown in FIG.
Up / down inclined block 43 with retainer (not shown)
L and 41L are larger than the maximum relative tilt movement amount based on the output signal (Sd) from the controller 70 in FIG. 12, and the maximum relative tilt movement amount constrained by this stroke end detection is , Is smaller than the maximum relative tilt movement amount based on the output signal (Sd) from the controller 70. That is, the safety measures for device protection are set in three stages.

In FIG. 12 showing the lifting drive control system,
A controller 70 including a PU, a ROM, a ROM, an interface, and the like uses the setting signal Sm from the setting device 75 as a target signal, and uses the detected height position signal output from the height position detecting means 50 as a feedback signal f as a motor 31.
The control signal Sd can be output to the driver 71 of FIG. That is, a closed loop rotation control circuit is configured. The minimum value (resolution) of the setting signal Sm set by the setting device 75 is 0.1 μm.

The motor 31 is forcibly stopped when the limit detecting means 60 detects the stroke end. This is for equipment protection.

The controller 70 uses the detected height position signal (f) to increment the display signal Si.
Can be output. The display unit 80 is a digital display system, the display value can be cleared to zero by a reset operation using the reset button 81, and the minimum position is 0.05 μm in the height position corresponding to the input increment display signal Si.
Can be displayed. The minimum display unit can be switched to the same as the resolution (0.1 μm). Also,
Using the origin (home position), the display can be selectively switched to an absolute display.

Therefore, a remarkably high precision positioning can be performed as compared with the case of the conventional example in which the open loop control is performed. That is, in this embodiment, the set value (0.1 μ
With respect to m), it could be confirmed from the display of the display 80 that the elevation table 20 could be positioned with high accuracy of ± 0.1 μm or less.

In the embodiment having such a configuration, a signal Sd is output from the controller 70 of FIG.
When the motor 31 forming the driving means 30 is driven to rotate the screw shaft (33) in one direction (for example, left rotation direction), a pair of slide blocks 36L and 36R shown in FIG.
Are separated in the axial direction of the screw shaft (33). That is,
A pair of lower inclined blocks 41L, 41R (inclined surfaces 41S,
41S) can be spaced apart in the axial direction.

Then, since the upper inclined blocks 43L and 43R are fixed to the elevating table 20 so as to be relatively immovable in the axial direction, the respective inclined surfaces 43S and 43S correspond to the corresponding inclined surfaces 41S and 41S of the corresponding lower inclined block. Rise along. The lifting table 20 can be raised.
The height (elevation) position of the elevating table 20 is determined by the distance between the lower inclined blocks 41L and 41R in the axial direction after separation. That is, it is determined by the rotation angle of the motor 31 corresponding to the set value set in the setter 75 (in this embodiment, the maximum value is 5.0000 mm).

During this period, the height position detecting means 50 operates to detect the current height position of the lifting table 20.
Since the detected height position signal (f) shown in FIG. 12 is fed back to the controller 70 as a feedback signal f, the elevation table 20 can be positioned at a high accuracy of the set value ± 0.1 μm or less. The value is displayed on the display 80.

Next, the motor 31 is driven to drive the screw shaft (3
When 3) is rotated in the other direction (rightward rotation direction), the pair of slide blocks 36L and 36R approach in the axial direction of the screw shaft (33). That is, a pair of lower inclined blocks 4
1L and 41R (inclined surfaces 41S and 41S) are made to approach in the axial direction. Then, the respective inclined surfaces 43S, 43S of the upper inclined blocks 43L, 43R descend along the corresponding inclined surfaces 41S, 41S of the corresponding lower inclined blocks. That is,
The lifting table 20 can be lowered. In this case, the height (down) position of the lifting table 20 is also determined by the distance between the lower inclined blocks 41L and 41R in the axial direction after approaching. That is, it is determined by the rotation angle of the motor 31 corresponding to the set value set in the setter 75 (in this embodiment, the minimum value is 0.0000 mm).

That is, each lower inclined block 41L, 41
The R approaching movement is performed by the respective upper inclined blocks 43L and 43.
Since the motion can be converted into the vertical movement of R, the eccentric load can be canceled at the time of vertical movement. Therefore, the lifting table 20 can be moved up and down with high resolution and the height can be positioned with high accuracy, and a significant reduction in size and cost can be achieved.

In addition, each of the upper inclined blocks 43L, 43R
Inclined surface 43S, 43S and each lower inclined block 41L, 4
The corresponding inclined surfaces 41S and 41S of the 1R are linear bearings (45).
A, 45B), so that it can be slidably guided in the inclined direction, so that a smooth up-and-down movement can be performed. That is, the load on the driving means 30 (31) can be reduced.

Further, four urging means (25) are provided between the base plate 10 and the lifting table 20, and the inclined surface of each upper inclined block is pressed against the corresponding inclined surface of each lower inclined block. Backlash can be eliminated. That is, positioning can be performed with higher accuracy.

Further, the scale 51 and the position detector 5
2, a high-resolution (0.1 μm or less) height position detection means 50 is provided and the motor 31 is formed so as to be capable of feedback rotation control using the detected height position signal (f). Height positioning can be performed with remarkably high precision (± 0.1 μm or less) as compared with the conventional example of open control.

[0053]

According to the first aspect of the present invention, a pair of slide blocks are mounted so that the drive means can be separated from and approach the pair of slide blocks in the axial direction by reversible rotation driving of the motor, and the lifting and lowering mechanism can be separated and approach. It includes a lower inclined block and a pair of upper inclined blocks fixed to the elevating table so as to be immovable relative to each other in the axial direction, and formed so that the separation approaching movement of each lower inclined block can be converted into the elevating movement of each upper inclined block. Since the lifting / lowering positioning device is used, the following excellent effects can be obtained.

An eccentric load generated when the elevating table moves up and down can be offset. That is, since the uneven load is not generated, the upper surface of the lifting table can be maintained horizontal, so that the height positioning accuracy can be greatly improved as compared with the conventional example, and the three-dimensional attitude of the lifting table can be kept constant. Therefore, the posture of the sample to be inspected on the lifting table can be stabilized. Therefore, for example, it is possible to drastically expand the industrial use in tests and research requiring high-precision height positioning of, for example, ± 0.1 μm or less.

Since the corresponding two inclined surfaces are used, the inclination angle of each inclined surface can be made larger than that of the conventional example. Therefore, significant downsizing and low cost in the axial direction can be achieved.

Since the lifting mechanism does not generate an eccentric load, the conventional large-sized, high-cost lifting guide mechanism can be eliminated. Therefore, the size of the apparatus can be greatly reduced and the cost can be reduced, and the installation of the high-resolution height position detecting means can be easily performed, and the closed-loop control can be easily introduced.

According to the second aspect of the present invention, the upper inclined block-side inclined surface and the lower inclined block-side inclined surface are guided slidably in the inclined direction via the linear bearing. In addition to achieving the same effects as in the case of the invention of Item 1, it is possible to perform a more smooth lifting movement. Further, the load on the driving means can be reduced, and the correspondence between the axial distance between the lower inclined blocks and the elevation position of the elevation table can be ensured with high accuracy and reliability.

According to the third aspect of the present invention, the urging means is provided between the base plate and the elevating table so that the inclined surface of each upper inclined block can be pressed against the corresponding inclined surface of each lower inclined block. Therefore, in addition to providing the same effects as in the case of each of the first and second aspects of the present invention, positioning can be performed with even higher precision.

Further, according to the fourth aspect of the present invention, there is provided a height position detecting means including a scale and a position detector attached to the base plate and the elevating table, and capable of detecting the height position of the elevating table with respect to the base plate. Since the motor constituting the driving means is formed so as to be capable of feedback rotation control, the same effects as those of the inventions according to the first to third aspects can be obtained. In comparison with the case of (1), the height can be positioned with remarkably high accuracy.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a left side view of the same.

FIG. 3 is also a right side view.

FIG. 4 is also a front view.

FIG. 5 is a plan view for explaining a state where the lifting table is removed.

6 is a left side view based on the line AA of FIG. 5;

FIG. 7 is a right side sectional view based on the line BB of FIG. 5;

8 is a front sectional view based on the line CC of FIG. 5;

9 is a cross-sectional view based on the line DD of FIG. 8;

FIG. 10 is a view for explaining a height position detecting means.

FIG. 11 is a diagram for explaining a limit detection unit.

FIG. 12 is also a diagram for explaining a lifting drive control system.

FIG. 13 is a view for explaining a modification of the lifting mechanism.

FIG. 14 is a front sectional view for explaining a conventional example.

[Explanation of symbols]

 Reference Signs List 10 base plate 12 linear bearing rail 13 linear bearing moving block 15 ball screw bracket 18 spring hook 20 lifting table 25 spring (biasing means) 30 driving means 31 motor 33 ball screw shaft (screw shaft) 35 ball flange 36 slide block 40 lifting mechanism 41 Lower inclined block 41S Inclined surface 43 Upper inclined block 43S Inclined surface 45 Linear bearing 50 Height position detecting means 51 Scale 52 Position detector 60 Limit detecting means 62 Photosensor 70 Controller 75 Setting device 80 Display 90 Elevating guide mechanism

Claims (4)

[Claims] A lifting table is mounted on a base plate via a lifting mechanism, and a driving means is activated to operate the lifting mechanism so that the lifting table can be raised and lowered and positioned at a set height position. In the apparatus, the driving unit is configured to reversibly rotate a screw shaft by reversible rotation driving of a motor to form a pair of slide blocks so as to be separated and approachable in the axial direction of the screw shaft. A pair of lower inclined blocks attached to the respective slide blocks so as to be able to be separated and approached together with the blocks, and the elevating table in which the respective inclined surfaces correspond to the respective inclined surfaces of the respective lower inclined blocks and cannot be relatively moved in the axial direction. And a pair of upper inclined blocks fixed to the upper and lower inclined blocks to move the lower inclined blocks away from each other. It is convertible to form the dynamic, lifting positioner. 2. The vertical positioning device according to claim 1, wherein an inclined surface of each of the upper inclined blocks and a corresponding inclined surface of each of the lower inclined blocks are slidably guided in a direction of inclination via a linear bearing. 3. An inclined surface of each of the upper inclined blocks is formed to be able to press against a corresponding inclined surface of each of the lower inclined blocks by applying an urging force of urging means between the base plate and the elevating table. 3. The lifting / lowering positioning device according to claim 1, wherein 4. A height position that includes a scale attached to one of the base plate and the lifting table and a position detector attached to the other, and that can detect a height position of the lifting table with respect to the base plate. 4. The motor according to claim 1, further comprising a detecting means, wherein the motor is formed so as to be able to feedback-control the motor using a detected height position signal output from the height position detecting means.
The lifting / lowering positioning device according to any one of the above items.