JP4189796B2 - Feeder fitting - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a joint for a feeding device used in precision measuring machines such as a surface roughness measuring machine and a straightness measuring machine.
[0002]
[Prior art]
In precision feeding devices used in precision measuring machines such as surface roughness measuring machines and straightness measuring machines, the displacement in one direction perpendicular to the guide (movement) direction of the stylus is measured. High feed straightness and feed pitching angle accuracy are required.
[0003]
When a feed device having a feed screw, such as a feed screw or a ball screw, is applied as such a precision feed device, a feed screwed to the feed screw on a moving carriage (moving member) provided with a stylus is provided. It is common to directly fix the nut. However, there is a problem that the feed straightness fluctuates for each rotation of the feed screw due to the feed screw runout. When high straightness accuracy is required, it is necessary to eliminate this effect, so the feed nut is connected to the moving carriage via an Oldham coupling or wire, and the feed nut caused by the feed screw is connected by the Oldham coupling or wire. Absorbed the shake.
[0004]
[Problems to be solved by the invention]
However, when the Oldham coupling is used, it is possible to absorb vibrations in all directions orthogonal to the feed direction, but there is a problem that frictional force is generated due to the shake and backlash in the feed direction remains.
[0005]
Also, in order to reduce the force caused by the deflection in the direction perpendicular to the guide direction by the wire, it is necessary to reduce the wire diameter and lower the tension, but this will reduce the rigidity in the feed direction, so the thrust of the feed nut will move. There was a problem that it could not be transmitted to the carriage.
[0006]
Further, these joints can absorb the displacement of the tilt component as well as the displacement of the horizontal and vertical translation components, but the rotation errors such as pitching and yawing are not sufficiently removed. If it is intentionally made a flexible structure, it can be removed, but there is a problem that the rigidity in the important feed direction cannot be secured. Furthermore, in order to eliminate the frictional force caused by motion, which is a problem with Oldham joints, it is conceivable to use hydrostatic air bearings or magnetic bearings. It was.
[0007]
The present invention has been made in view of the above circumstances, and prevents vertical displacement and pitching and yawing errors of the feed screw due to the feed screw from being transmitted to the moving member. An object of the present invention is to provide a feeder joint having high rigidity.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a joint of a feed device that connects a feed nut screwed to a feed screw and a moving member, wherein the joint is moved in the direction of movement of the moving member across the feed nut. Located on both sides, one end is connected to the feed nut and the other end is connected to an intermediate member, and the deflection of the feed nut in the direction perpendicular to the feed screw is elastic to one side. One end of the first leaf spring member that is deformed and absorbed, and one end of the intermediate member are connected to the moving member, and the other end is connected to the moving member, and the feed nut swings in a direction perpendicular to the feed screw. A second leaf spring member that elastically deforms and absorbs vibration in the other direction orthogonal to the one direction side, and the intermediate member coupling portion to which the second leaf spring member is coupled Protrudes toward the feed nut Both are characterized by being positioned on substantially the same plane with respect to a plane perpendicular to the axis of the first connecting portion of the feed nut side and the leaf spring member is connected the feed screw.
[0009]
According to the first aspect of the present invention, the leaf spring member whose surface is oriented in the horizontal direction (one direction) and the vertical direction (the other direction) is provided on the moving member via the intermediate member, thereby perpendicular to the feed direction. When the leaf spring member is elastically deformed with respect to a displacement in any direction, the displacement is absorbed without frictional force, and the transmission of the displacement to the moving member is cut off.
[0010]
In addition, by applying a leaf spring member, the rigidity in the feed direction is significantly improved compared to conventional joints that use wires such as wires. Can prevent transmission.
[0011]
Further, in the Oldham joint, a frictional force acts when escaping in the vertical direction, and displacement transmission remains. Further, when a static pressure type air bearing or a magnetic bearing is used, the clearance and rigidity in the pitching direction are insufficient, but this leaf spring type joint can satisfy these conflicting requirements.
[0012]
The leaf spring can achieve a tensile rigidity determined by the Young's modulus in the tensile direction, but has a characteristic that the rigidity becomes extremely low due to buckling against a force in the compression direction.
[0013]
In order to avoid this decrease in rigidity, the joints are arranged on both sides of the moving member in the moving direction and connected to the feed nut from both sides. When the feed nut is driven to the left side, a tensile force acts on the right joint, and the displacement of the feed nut is transmitted to the moving member in a state of high rigidity. On the other hand, when the feed nut is driven to the right side, similarly, a pulling force acts on the left joint, and the displacement of the feed nut is transmitted to the moving member in a state of high rigidity.
[0014]
Further, if a pair of the first leaf spring member and the second leaf spring member are provided and these leaf spring members are arranged in parallel with the feed screw with the feed screw interposed therebetween, both directions on one side and the other side are provided. Can reliably absorb the fluctuations. Moreover, the pitching of the feed nut can be absorbed by arranging these leaf spring members so that the extension line of the surface of these leaf spring members faces the center of the feed screw.
[0015]
According to the onset bright, the connecting portion of the intermediate member is a second leaf spring member is connected, together protrudes toward the feed nut, the feed nut the first plate spring member is connected It is characterized in that it is positioned on substantially the same plane with respect to a plane orthogonal to the connecting portion on the side and the axis of the feed screw.
[0016]
In this way, the equivalent execution length of the joint can be made longer than the length of the moving member by the structure in which the connecting portion of the intermediate member to which the second leaf spring member is connected protrudes to the feed nut side. Absorption function against lateral displacement and inclination of the joint is improved. Further, the connecting portion of the intermediate member to which the second leaf spring member is connected and the connecting portion of the feed nut to which the first leaf spring member is connected are located on the same plane with respect to the surface orthogonal to the feed screw. As a result, the pitching of the feed nut can be absorbed.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiments of the joint of the feeder according to the present invention will be described in detail below with reference to the accompanying drawings.
[0018]
FIG. 1 is a perspective view showing a surface roughness measuring machine 102 to which the precision feeding device 100 of the embodiment is applied. The surface roughness measuring machine 102 is attached with the measuring object 108 adjusted in position by a position adjusting device 106 installed on the measuring unit base 104. Further, a column 110 is erected on the measurement unit base 104, and a driving device 112 in which the feeding device 100 is built is provided on the column 110 so as to be movable up and down (Z-axis direction). The feeding device 100 includes a moving side carriage 25 in which a feed screw 2, a motor 116, and a feeding nut (not shown) are provided, and a detector 120 provided with a stylus 118 is connected to the moving side carriage 25. Yes.
[0019]
According to the surface roughness measuring machine 102 configured as described above, the driving device 112 is moved down along the column 110 to bring the stylus 118 into contact with the measurement object 108. Thereafter, the motor 116 of the feed device 100 is driven to rotate the feed screw 2 and the moving carriage 25 is moved horizontally (X direction) by the thrust of the feed nut, whereby the stylus 118 is moved to the measurement object 108. Accordingly, the roughness of the measurement object 108 is measured by the detector 120 by moving the stylus 118 up and down (Z direction).
[0020]
The surface roughness measuring machine 102 is required to have a high straightness in the Z-axis direction of the moving carriage 25 in order to measure the roughness by moving the stylus 118 up and down. For this reason, the joint according to the embodiment is provided in the moving carriage 25. This joint will be described later.
[0021]
FIG. 2 is a perspective view showing a straightness measuring machine 122 to which the feeding device 100 of the embodiment is applied, and FIG. 3 is an assembly perspective view of the feeding device 100. In the straightness measuring machine 122, a position adjustment table 124 is provided so as to be movable in the X-axis direction along the X-axis feed stage fixed guide surface 1, and the position of the measuring object 108 is adjusted and attached to the position adjustment table 124. . A column 126 is erected on the guide member 1B on which the X-axis feed stage fixed guide surface 1 is formed, and a stylus 130 is provided on the column 126 via a Z-axis displacement detector 128.
[0022]
According to the straightness measuring machine 122 configured as described above, after the stylus 130 is brought into contact with the measurement object 108, the motor 116 of the feeder 100 is driven to rotate the feed screw 2, and the configuration shown in FIG. The moving carriage 25 connected to the lower part of the position adjustment table 124 is moved in the X-axis direction by the thrust of the feed nut 3. Thereby, the displacement in the Z-axis direction is measured by the Z-axis displacement detector 128, and the XZ cross-sectional contour shape of the measurement object 108 is obtained.
[0023]
FIGS. 4 to 9 show structural diagrams of the joint 60 according to the embodiment.
[0024]
As shown in FIG. 2 , the guide 1B on which the X-axis feed stage fixed guide surface 1 is formed has a relief groove (not shown) through which the feed screw 2 and the joint can move, and the moving carriage 25 in FIG. The X-axis feed stage fixed guide surface 1 (see FIG. 2) is slidably supported via the position adjustment table 124 and a bearing (not shown) . A feed nut 3 shown in FIG. 4 screwed to the feed screw 2 is fixed to the feed nut housing 4. 4 horizontal strip leaf springs (first leaf spring members) 5, 6, 35 on the right and left sides of the feed nut housing 4 across the feed nut housing 4, that is, on both sides of the feed nut in the moving direction. 36 is fixed by four horizontal strip spring retainers 7, 8, 37, 38. The horizontal strip leaf springs 5 and 6 are disposed in parallel with the feed screw 2 with the feed screw 2 interposed therebetween, and the horizontal strip leaf springs 35 and 36 are also disposed in the same manner.
[0025]
The horizontal strip leaf springs 5, 6, 35, 36 are reinforced at their intermediate portions by two leaf spring retainers 9, 10, 11, 12, 39, 40, 41, 42 on the front and back sides, respectively. Are fixed to the intermediate members 15 and 34 by one horizontal leaf spring retainer 13, 14, 43 and 44, respectively.
[0026]
Further, vertical strip leaf springs (second leaf spring members) 17, 18, 26, and 27 are fixed to the intermediate members 15 and 34 by a single vertical leaf spring retainer 23, 24, 32, and 33, respectively. The vertical strip leaf springs 17, 18, 26, and 27 are reinforced at their middle portions by two leaf spring retainers 19, 20, 21, 22, 28, 29, 30, and 31, respectively. Are fixed to the side walls 25A, 25B arranged on both sides of the movable carriage 25 with a predetermined tension. The vertical strip springs 17 and 18 are disposed in parallel with the feed screw 2 with the feed screw 2 interposed therebetween, and the vertical strip springs 26 and 27 are also disposed in the same manner.
[0027]
According to the joint 60 configured in this way, the horizontal strip springs 5, 6, 35, and 36 whose surfaces are directed in the horizontal direction, and the vertical strip springs 17, 18, and 26 whose surfaces are directed in the vertical direction. , 27 with the predetermined tension on the moving carriage 25 via the intermediate members 15, 34, the horizontal strip springs 5, 6, 35, 36 and vertical against displacement in the direction perpendicular to the feed. By the elastic deformation of the strip springs 17, 18, 26, 27, the displacement can be absorbed without frictional force, and the transmission of the displacement to the moving carriage 25 can be cut off. Also, by applying the horizontal strip springs 5, 6, 35, 36 and the vertical strip springs 17, 18, 26, 27, the rigidity in the feed direction can be remarkably improved and the feed by the feed screw 2 can be improved. Can absorb runout and pitching error perpendicular to the direction.
[0028]
In addition, a pair of horizontal strip springs 5, 6, 35, 36 and vertical strip springs 17, 18, 26, 27 are provided on both sides of the feed nut 3, respectively, and these horizontal strip springs 5, 6, Since 35, 36 and the vertical strip springs 17, 18, 26, 27 are arranged in parallel with the feed screw 2 with the feed screw 2 interposed therebetween, the vibration in the direction orthogonal to the feed screw 2 can be reliably absorbed.
[0029]
Further, as shown in FIGS. 7 and 8, the extension lines 5A, 6A, 35A, 36A, 17A of the surfaces of the horizontal strip springs 5, 6, 35, 36 and the vertical strip springs 17, 18, 26, 27 are provided. , 18A, 26A, 27A are disposed so that the horizontal strip leaf springs 5, 6, 35, 36 and the vertical strip leaf springs 17, 18, 26, 27 are oriented so that the center of the feed screw 2 is 2A. 2 pitching can be absorbed.
[0030]
By the way, in the joint 60 of the embodiment, as shown in FIG. 4, the connecting portions 62, 64, 66, 68 of the intermediate members 15, 34 to which the vertical strip leaf springs 17, 18, 26, 27 are connected are the feed nut 3. It is formed to project toward. Further, these connecting portions 62, 64, 66, 68 are connected to connecting portions 70, 72, 74, 76 of the feed nut housing 4 on the feed nut 3 side to which the horizontal strip springs 5, 6, 35, 36 are connected. It is positioned substantially on the same plane as a plane 78 indicated by a two-dot chain line in FIG.
[0031]
As described above, the connecting portions 62, 64, 66, and 68 of the intermediate members 15 and 34 to which the vertical strip springs 17, 18, 26, and 27 are connected are projected to the feed nut 3 side. Since the equivalent execution length can be made longer than the length of the moving-side carriage 25, the function of absorbing the lateral displacement and inclination of the joint 60 is improved.
[0032]
Further, since the connecting portions 62, 64, 66, 68 and the connecting portions 70, 72, 74, 76 are positioned substantially on the same plane with respect to the surface 78 orthogonal to the feed screw 2, the pitching of the feed nut 3 is absorbed. it can.
[0033]
Furthermore, since the horizontal strip springs 5, 6, 35, and 36 are disposed in a plane having the same height as the gravity center of the sliding force of the movable carriage 25, the couple that causes pitching displacement is reduced.
[0034]
Further, by arranging the swing center of the left and right horizontal strip springs 5, 6, 35, 36 on the movable carriage 25 side at substantially the same position in the feed direction, even if a pitching change occurs in the feed nut 3, The couple in the pitching direction is prevented from acting on the moving carriage 25.
[0035]
The vertical strip springs 17, 18, 26, 27 escape against displacement and inclination (yawing) in a direction perpendicular to the driving direction and parallel to the X-axis feed stage fixed guide surface 1, so that the force in this direction is guided. Transmission to the surface 1 can be prevented.
[0036]
In the embodiment, as described above, the connecting portions 62, 64, 66, 68 and the connecting portions 70, 72, 74, 76 are positioned substantially on the same plane with respect to the surface 78 orthogonal to the feed screw 2. However, the present invention is not limited to this. That is, even if the connecting portions 62, 64, 66, and 68 and the connecting portions 70, 72, 74, and 76 are formed to be shifted in the horizontal direction, the surface roughness measuring instrument 102 is not hindered in measurement accuracy. That is, in the surface roughness measuring machine 102, since the displacement of the feed nut 3 in the Z-axis direction is caused by a measurement error, even when the shifted structure is adopted, the displacement in the Z-axis direction can be sufficiently achieved without friction force. Absorb. Therefore, the measurement accuracy is improved without affecting the measurement accuracy.
[0037]
【The invention's effect】
As described above, according to the joint of the feeding device according to the present invention, the leaf spring member whose surface is directed to the one direction side and the other direction side is provided on the moving member via the intermediate member. When the leaf spring member is elastically deformed with respect to the displacement in the vertical direction, transmission of the displacement to the moving member can be cut off. Further, by applying the leaf spring member, the rigidity in the feed direction is remarkably improved, and vibrations and pitching errors perpendicular to the feed direction by the feed screw can be absorbed.
[0038]
Further, according to the present invention, the equivalent effective length of the joint is made longer than the length of the moving member by the structure in which the connecting portion of the intermediate member to which the second leaf spring member is connected protrudes to the feed nut side. Therefore, the absorption function with respect to the lateral displacement and inclination of the joint is improved. Further, the connecting portion of the intermediate member to which the second leaf spring member is connected and the connecting portion on the feed nut side to which the first leaf spring member is connected are on the same plane with respect to the surface orthogonal to the feed screw. Because it is positioned, the pitching of the feed nut can be absorbed.
[Brief description of the drawings]
FIG. 1 is a perspective view of a surface roughness measuring machine to which a joint of the precision feeding device of the embodiment is applied. FIG. 2 is a perspective view of a straightness measuring machine to which the joint of the precision feeding device of the embodiment is applied. 3 is an assembled perspective view of the precision feeding device of the straightness measuring machine shown in FIG. 2. FIG. 4 is an assembled perspective view of a joint of the precision feeding device of the embodiment. FIG. FIG. 6 is a plan view showing the structure of the joint of the precision feeding device. FIG. 7 is a side view of the joint as viewed from line 7-7 in FIG. 6. FIG. Side view of the joint as seen from line 8 [FIG. 9] Side view of the joint of the precision feeder shown in FIG.
DESCRIPTION OF SYMBOLS 1 ... X-axis feed stage fixed guide surface, 2 ... Feed screw, 3 ... Nut, 4 ... Nut housing, 25 ... Moving side carriage, 5, 6, 35, 36 ... Horizontal strip spring, 7, 8, 37, 38 ... Horizontal leaf spring retainer, 9, 10, 11, 12, 39, 40, 41, 42 ... Leaf spring retainer, 15, 34 ... Intermediate member, 13, 14, 43, 44 ... Horizontal leaf spring retainer, 17, 18 , 26, 27 ... vertical strip springs, 23, 24, 32, 33 ... vertical leaf spring retainers, 19, 20, 21, 22, 28, 29, 30, 31 ... leaf spring retainers, 60 ... joints, 100 ... feed Apparatus 102 ... Surface roughness measuring machine 122 ... Straightness measuring machine

Claims (1)

In the joint of the feed device that connects the feed nut screwed to the feed screw and the moving member,
The joint is disposed on both sides of the moving member in the moving direction across the feed nut, and one end is connected to the feed nut and the other end is connected to an intermediate member, and is perpendicular to the feed screw. A first leaf spring member that elastically deforms and absorbs one-side vibration among the directional feed nut vibrations;
One end is connected to the intermediate member, the other end is connected to the moving member, and the other side of the feed nut in a direction perpendicular to the feed screw is perpendicular to the one direction. A second leaf spring member that elastically deforms and absorbs vibration ,
A connecting portion of the intermediate member to which the second leaf spring member is connected protrudes toward the feed nut, and a connecting portion on the feed nut side to which the first leaf spring member is connected and the feed. A joint for a feeding device, wherein the joint is located on substantially the same plane with respect to a plane perpendicular to the axis of the screw .

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