JP2001221229A - Linear motion bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a linear motion bearing capable of linearly moving at high speed with high accuracy over a long distance, hardly generating noise. SOLUTION: In a wheel bearing unit, a cylindrical pin is inserted in a hollow part of a hollow cylindrical wheel through plural rolling elements, and the wheel turns around the pin. The wheel bearing unit is disposed near the inner face of a bush such that the center axis of the pin is oriented to the circumferential direction of the bush. The pin is fixed to the bush. The wheel is installed such that the wheel does not contact with the bush and that a portion of the wheel on the center side of the bush projects from the inner face of the bush to the center side and is exposed. The plural wheel bearing units are disposed along the side line of the bush side by side to form wheel bearing unit lines. The side face of a guide is formed with flat surface parts parallel to the center axis of the guide. The respective wheels in the wheel bearing unit lines turn and travel with contacting with the corresponding flat surface parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a linear motion bearing. The linear motion bearing according to the present invention includes a punching process, a bending process, a drawing process, a coining process and a forging process, a rubber mold process, and a mold process for a metal plate, a metal foil, a plastic sheet, a plastic film, a glass sheet and the like. It can be used for die set for press die used for die casting, powder molding, etc. Also, semiconductor manufacturing equipment such as prober, precision scientific instrument, measuring instrument, optical instrument, copier, printer, electric instrument, etc. It can be used for precision drilling machines such as drills and punches, press machines, and injection molding machines.

[0002]

2. Description of the Prior Art FIG. 2 is a perspective view of a guide post, a retainer and a bush for a press die set of the first prior art. Hollow cylindrical bush 1
The cylindrical guide post 3 is inserted into the hollow part of the above-mentioned, with the retainer 2 holding a large number of rolling elements 22 rotatably held in a thin-walled frame 21 having a hollow cylindrical shape, and the guide post 3 is linearly moved. is there. Rolling elements include ball bearings, roller bearings, needle bearings,
Cross roller bearings and hourglass bearings can be mentioned.

FIG. 3 is a sectional view of a linear motion block and a guide rail according to a second prior art. A running path 41 is formed on the surface of the linear motion block 4, a return path 42 is formed therein, and the running path 41 and the return path 42 are connected by connecting portions 43 and 44 to form an annular circulation path. is there. A large number of ball bearings 45 to 49 are connected to each other, arranged in an annular circulation path, and run.
The ball bearings 45 and 46 running on the running path 41 on the surface of the linear motion block 4 also rotate while running on the surface 51 of the guide rail 5. Further, the ball bearings 45 and 46 are sandwiched between the linear motion block 4 and the guide rail 5, and a compressive load is applied. On the other hand, connection part 4
3, 44 and ball bearing 4 in return path 42
7, 49, 48 do not contact the guide rail 5.

[0004]

However, in the first prior art, linear movement is possible only within a range where the retainer does not fall off the guide post or the bush. In other words, the bush cannot be linearly moved accurately over a long distance along the long guide post or guide shaft.

On the other hand, in the second prior art, a linear motion can be performed over a long distance. However, a ball bearing runs, and one ball is moved from the tip in the running direction to the running path 41 of the linear motion block 4. The bearing enters, and at the same time, one ball bearing exits from the rear end in the running direction, and noise and vibration are generated by the ball bearing released from the compressive load. Therefore, noise and vibration are periodically generated in accordance with the traveling speed of the linear motion block, and high accuracy cannot be maintained.

SUMMARY OF THE INVENTION An object of the present invention is to provide a linear motion bearing capable of high-speed linear motion with high accuracy over a long distance and generating almost no noise.

[0007]

The object of the present invention is to provide a linear motion bearing according to the first aspect of the present invention, that is, a cylindrical guide is inserted into a hollow portion of a hollow cylindrical bush and is guided by the guide. A bush is linearly moved along the center axis of the guide, and a cylindrical pin is inserted through a plurality of rolling elements into a hollow portion of a hollow cylindrical wheel, and the wheel is mounted on the pin. A wheel bearing unit that rotates around is arranged near the inner surface of the bush so that the center axis of the pin is oriented in the circumferential direction of the bush, and the pin is fixed to the bush. A plurality of wheels that are not in contact with the bush, and that have a portion of the wheel closer to the center of the bush protruding toward the center from the inner surface of the bush and being exposed and mounted; A bearing unit is arranged on a side line of the bush to form a row of wheel bearing units, and a flat portion parallel to a central axis of the guide is formed on a side surface of the guide; Each wheel is achieved by a linear motion bearing which rotates and travels in contact with a corresponding plane.

[0008] The object of the present invention is to provide a linear motion bearing according to the present invention, that is, by inserting a cylindrical guide into a hollow portion of a hollow cylindrical bush having a notch.
A bush is guided by the guide and the bush moves linearly along the center axis of the guide.A cylindrical pin is inserted into the hollow portion of the hollow cylindrical wheel through a plurality of rolling elements, and the wheel is A wheel bearing unit that rotates around the pin is arranged near the inner surface of the bush so that the center axis of the pin is oriented in the circumferential direction of the bush, and the pin is fixed to the bush. The wheel does not contact the bush, and a portion of the wheel near the center of the bush protrudes toward the center from the inner surface of the bush and is exposed and mounted, and a plurality of wheel bearing units are mounted on the bush. A row of wheel bearing units is arranged side by side, and a flat surface parallel to the center axis of the guide is formed on the side surface of the guide. Are, each wheel of the wheel bearing unit column by a linear motion bearing which runs rotated in contact with the flat portion corresponding is achieved.

The object of the present invention is to provide a linear motion bearing according to the present invention, that is, a cylindrical guide is inserted into a hollow portion of a hollow cylindrical bush, and the center of the guide is guided by the guide. A bearing in which the bush moves linearly along the axis, and in the hollow portion of a hollow cylindrical wheel,
A cylindrical pin is inserted through the sliding body, and the wheel rotates the wheel bearing unit around the pin near the inner surface of the bush, and the center axis of the pin moves in the circumferential direction of the bush. The pin is fixed to the bush, the wheel does not contact the bush, and the portion of the wheel near the center of the bush projects toward the center from the inner surface of the bush and is exposed. A plurality of wheel bearing units are arranged on the side line of the bush to form a row of wheel bearing units, and a flat portion parallel to the center axis of the guide is formed on a side surface of the guide. Each of the wheels in the row of wheel bearing units is also driven by a linear motion bearing that rotates and runs in contact with the corresponding flat part. It is achieved.

[0010] Further, the object of the present invention is to provide a linear motion bearing according to a fourth aspect of the present invention, that is, to insert a cylindrical guide into a hollow portion of a hollow cylindrical bush having a notch and guide the guide into the guide. The bush is a bearing in which the bush moves linearly along the center axis of the guide, and a cylindrical pin is inserted into the hollow portion of the hollow cylindrical wheel via a sliding body, and the wheel moves around the pin. A rotating wheel bearing unit is arranged near the inner surface of the bush so that the center axis of the pin is oriented in the circumferential direction of the bush, and the pin is fixed to the bush;
The wheel is not in contact with the bush, and a portion of the wheel near the center of the bush is mounted so as to protrude toward the center from the inner surface of the bush and is exposed, and a plurality of wheel bearing units are mounted on the bush. A row of wheel bearing units is arranged side by side, and a flat portion parallel to the central axis of the guide is formed on a side surface of the guide, and each wheel of the wheel bearing unit row is a corresponding flat portion. This is also achieved by a linear motion bearing that rotates and travels in contact with the bearing.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view of a guide shaft and a bush according to a first embodiment of the present invention.

The guide shaft 31 is substantially cylindrical.
On the side surface, flat surfaces 312, 313, 314 parallel to the central axis 311 of the guide shaft 31 are formed.
Planes 312, 313, 314 are 1 around the central axis.
They are arranged symmetrically at 20 ° intervals.

The bush 11 has a substantially hollow cylindrical shape, and the wheel bearing units 61, 62, and 63 have pins 611, 621, and 631 of the wheel bearing units 61, 62, and 63 near the inner surface of the bush 11, respectively. The center shafts 612, 622, 632 are arranged so as to face the circumferential direction of the bush 11. That is, the pins 611,
621 and 631 are in the same plane perpendicular to the central axis of the bush 11 (coincident with the central axis 311 of the guide shaft 31), and the central axis 61 of the pins 611, 621 and 631
The vertical bisectors of 2, 622, and 632 each point in the radial direction of the bush 11 and all pass through the central axis of the bush 11.

FIG. 4 is an enlarged view of the periphery of the wheel bearing unit 63 in FIG. The wheel bearing unit 63 is a hollow cylindrical wheel 633.
Is a mechanical element in which a cylindrical pin 631 is penetrated through a rolling member or a sliding member (not shown) through a hollow portion, and a wheel 633 rotates in a circumferential direction of the pin 631. A wheel bearing unit using a hole bearing or a needle bearing as a rolling element is commercially available under a trade name such as a wheel pack. The vicinity of both ends of the pin 631 is supported by parts 634 and 635 of the case. The pin 631 may be supported rotatably about its central axis, or may be fixedly supported.

Wheel bearing units 61, 6
The wheels 2 and 63 are arranged so as to freely rotate without contacting the bush 11.

Wheel bearing units 61, 6
Position adjustment screws 616, 626, and 636 for finely adjusting the positions of the position adjustment screws 2 and 63 in the radial direction of the bush 11 are attached.
38 is exposed from the outer surface side of the bush 11, and the position adjusting screw can be easily rotated forward and reverse at any time without disassembling the bearing using a screwdriver or a hexagon wrench. The tip of the thread 637 of each of the position adjusting screws 616, 626, 636 is machined into a flat surface and abuts a part of the case of the wheel bearing units 61, 62, 63. Therefore, the position adjustment screw 616,
The positions of the wheel bearing units 61, 62, 63 can be adjusted independently of each other by means of 626, 636.

When the guide shaft 31 is inserted into the hollow portion of the bush 11 and assembled, the guide shaft 31
Are in contact with the wheel bearing units 61, 62, 63 of the bush 11,
It performs position adjustment and load sharing. The wheels of the wheel bearing units 61, 62, 63 respectively correspond to the planes 312, 313, 31 of the guide shaft 31.
The bush 11 is guided by the guide shaft 31 because it rotates in contact with the bush 4, so that the bush 11 can smoothly run straight along the central axis direction. When the wheels are assembled under a preload, that is, a state in which a compressive load is applied in advance, the positional accuracy of the bush 11 in the radial direction from the center axis of the guide shaft 31 is kept extremely high.

FIGS. 5A and 5B are views showing a case according to the embodiment of the present invention, wherein FIG. 5A is a front view and FIG. 5B is a side view. The case 7 is substantially a rectangular parallelepiped, and includes wheels (not shown) of a plurality of wheel bearing units.
Rectangular windows 701, 702, 703 to which are attached,
A circular through hole 710-722 into which pins (not shown) of a plurality of wheel bearing units are inserted, a screw hole 730 into which a screw portion (not shown) of a position adjusting screw is screwed;
731 is provided. The rectangular window 701 is fitted with two wheel bearing units,
2 has three wheel bearing units, and rectangular window 703 has two wheel bearing units.
Install the unit. The centers of the circular through holes 710 to 722 are offset from the center in the thickness direction of the case, and L1 is shorter than L2. Therefore, the wheel of the wheel bearing unit protrudes from the left side surface in FIG. 5B, but is located inside the right side surface.

FIG. 6 shows a wheel according to a second embodiment of the present invention.
It is the schematic of a bearing unit, (a) is the front view, (b) is the side view. In the wheel bearing unit 60 of the second embodiment, the needle bearings 801 and 802 of the rolling elements are
1 and the wheel 602, and the end plate 6
It is rotatably mounted between 03 and 604. As the material of the needle bearing, high-speed steel, bearing steel, cemented carbide and the like can be used.

FIG. 7 shows a wheel according to a third embodiment of the present invention.
It is the schematic of a bearing unit, (a) is the front view, (b) is the side view. In the wheel bearing unit 64 of the third embodiment, ball bearings 811, 812, 82 are used as rolling elements.
1, 822, 831, 832 are used and R-grooves 645, 646,
647 is formed in the wheel of the second embodiment.
It differs from the bearing unit, but is otherwise almost identical. As the material of the ball bearing,
Ceramics can be used in addition to high-speed steel, bearing steel, and cemented carbide.

FIG. 8 shows a fourth embodiment of the present invention.
It is the schematic of a bearing unit, (a) is the front view, (b) is the side view. In the wheel bearing unit 64 of the fourth embodiment, the sliding body 85 is attached to the surface of the center of the pin 651, and the outer surface of the sliding body 85 contacts the inner surface of the wheel 652 and slides in the circumferential direction. I do.

As a method of attaching the sliding body 85 to the surface of the pin 651, in addition to bonding, a wedge-shaped concave portion is provided on the surface of the pin, and after resin or the like is pressed and injected, it is solidified.
There is a method of using the anchor effect to detachably attach.

Although the sliding member 85 has a substantially cylindrical shape, it is preferable to form a disk-shaped or annular projection on the outer surface of the sliding member 85. Alternatively, it is preferable to form a discontinuous linear projection extending in the circumferential direction. Only the upper surfaces of these protrusions contact the inner surface of the wheel 652 to support the load. However, the contact area between the sliding body and the inner surface of the wheel is reduced, and the frictional resistance is reduced. can do. In addition, even if dirt or the like is mixed between the wheel and the sliding body, a part other than the protrusion of the sliding body does not contact the wheel and there is a gap. The inner surface of the wheel is less likely to be scratched.

As the material of the sliding body 85, carbon fiber-containing resin, glass fiber-containing resin, other resins, hard rubber,
Examples include ceramic-containing alloys and molybdenum disulfide-containing metals. Of course, these materials may be combined or combined.

FIG. 9 is a front view of a linear motion bearing according to a fifth embodiment of the present invention, and FIG. 10 is a sectional view taken along line AA in FIG.

The guide shafts 34 and 35 have a substantially cylindrical shape, and each side surface has a flat surface 34 parallel to the central axis.
5, 346; 355, 356 are formed. The guide shafts 34 and 35 are arranged in a straight line so that their central axes coincide, and are arranged horizontally. There is a slight gap between the guide shafts 34 and 35, but they may be parallel so as to be in close contact. The clearance between the guide shafts is designed so as not to prevent the bush from moving linearly, and care should be taken to prevent derailment or the like. At the lower part of the guide shaft 34, the joining projection 9 of the stand component 9 is provided.
A joint recess 341 that fits with the hole 01 is formed. The joining recess 341 may be continuous in the direction of the central axis of the guide shaft 34, or alternatively, the joining projection 90
It may be a discontinuous form of sufficient dimensions to fit with 1. A through hole 343 passing through the center upward from the bottom surface 342 of the joint recess 341 is formed. This through hole 34
3 has a circular cross section, and a screw 91 for joining the guide shaft 34 and the stand component 9 passes therethrough. Screw 91 is
It engages with a screw hole 903 formed vertically downward from the upper surface 902 of the joining projection 901 of the stand component 9.
In addition, the stand component 9 is formed by connecting the joining convex portion 901 and the base portion 905 by the tapered portion 904. That is, the narrow portion of the taper portion 904 is connected to the joining convex portion 901, and the wide portion of the tapered portion 904 is connected to the upper surface of the base portion 905. The base portion 905 has a through hole 90
6, 907 are formed, and the stand component 9 is fixed to the base component 10 by screws 92, 93.

As described above, by arranging a plurality of guide shafts on a horizontal plane and arranging them on a straight line, an infinite length of linear guide can be provided. Also, a similar linear guide can be provided on a vertical surface or on any other surface.

Although the bush 12 has a substantially hollow cylindrical shape, a cutout is provided in a part (the lower part in FIG. 10), and when the bush 12 is combined with the guide shafts 34 and 35 to perform a linear motion, It is designed so as not to hit the stand 9. In addition, wheel bearing
Units 64, 65, 66, 67 are located near the inner surface of the bush 12 and for each wheel bearing unit. The central axis is oriented in the circumferential direction of the bush 32.

In the first embodiment, three wheel bearing units are arranged one around the center of the bush.
Although they are arranged at an angle interval of 20 °, the fifth
The embodiment differs in that the four wheel bearing units are arranged at 90 ° angular intervals around the center of the bush.

In the fifth embodiment, the bush 12
The upper surface 151, the left side surface 152, and the right side surface 153 are flat. XY
When the linear motion bearing of the present embodiment is used for a table, the table is fixed on the upper surface of the block 15.

[0032]

According to the linear motion bearing of the present invention, the wheel bearing unit is mounted near the inner surface of the bush, and the linear motion is rotated on the plane provided on the guide. And noise and vibration are not generated.

[Brief description of the drawings]

FIG. 1 is a sectional view of a guide shaft and a bush according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a guide post, a retainer, and a bush for a first conventional press die set.

FIG. 3 is a cross-sectional view of a second prior art linear motion block and guide rail.

FIG. 4 is an enlarged view of the periphery of a wheel bearing unit 63 in FIG.

5A and 5B are diagrams showing a case according to the embodiment of the present invention, wherein FIG. 5A is a front view thereof, and FIG. 5B is a side view thereof.

FIG. 6 is a schematic view of a wheel bearing unit according to a second embodiment of the present invention, where (a) is a front view and (b) is a side view.

FIGS. 7A and 7B are schematic diagrams of a wheel bearing unit according to a third embodiment of the present invention, wherein FIG. 7A is a front view and FIG. 7B is a side view.

FIG. 8 is a schematic view of a wheel bearing unit according to a fourth embodiment of the present invention, where (a) is a front view and (b) is a side view.

FIG. 9 is a front view of a linear motion bearing according to a fifth embodiment of the present invention.

FIG. 10 is a sectional view taken along the line AA in FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bush 2 Retainer 3 Guide post 4 Linear motion block 5 Guide rail 7 Case 9 Stand part 10 Base part 11 Bush 12 Bush 15 Block 21 Frame 22 Rolling element 31 Guide shaft 33 Guide shaft 34 Guide shaft 41 Travel path 42 Return path 43 Connection 44 Connection 45 to 49 Ball bearing 51 Surface 60 Wheel bearing unit 61 Wheel bearing unit 62 Wheel bearing unit 63 Wheel bearing unit 64 Wheel bearing unit 65 Wheel bearing unit 66 Wheel・ Bearing unit 67 Wheel bearing unit 85 Sliding body 91 Screw 92 Screw 93 Screw 151 Upper surface 152 Left side surface 53 Right side surface 311 Central axis 312 Plane 313 Plane 314 Plane 321 Plane 322 Plane 331 Plane 332 Plane 341 Coupling recess 342 Bottom surface 343 Through hole 601 Pin 602 Wheel 603 End plate 604 End plate 611 Pin 621 Pin Center shaft 612 620 632 center axis 634 case 635 case 616 position adjusting screw 626 position adjusting screw 636 position adjusting screw 637 screw portion 638 head 645 R groove 646 R groove 647 R groove 651 pin 652 wheel 701 rectangular window 702 rectangular window 703 rectangular window 710-722 Circular through hole 801 Needle bearing 802 Needle bearing 811 Ball bearing 812 Ball bearing 821 Ball bearing 822 Baud Ball bearing 831 ball bearing 832 ball bearing 901 joint projection 902 top surface 903 screw hole 904 taper part 905 base part 906 through hole 907 through hole

Claims (14)

[Claims] 1. A bearing in which a cylindrical guide is inserted into a hollow portion of a hollow cylindrical bush, and the bush is guided by the guide and the bush moves linearly along a center axis of the guide. A cylindrical pin is inserted into the hollow portion through a plurality of rolling elements, and the wheel rotates a wheel bearing unit that rotates around the pin near the inner surface of the bush. The pin is fixed to the bush, the wheel is not in contact with the bush, and a portion of the wheel near the center of the bush is an inner surface of the bush. A plurality of wheel bearing units are protruded and exposed more toward the center, and a plurality of wheel bearing units are arranged side by side on the bush. The guide has a flat portion parallel to the central axis of the guide, and each wheel of the wheel bearing unit row is in contact with the corresponding flat portion, and rotates and travels in a straight line. Motion bearing. 2. A bearing in which a cylindrical guide is inserted into a hollow portion of a hollow cylindrical bush having a notch, and the bush is guided by the guide and the bush moves linearly along a central axis of the guide. A cylindrical pin is inserted through a plurality of rolling elements into the hollow portion of the shaped wheel, and the wheel bearing unit in which the wheel rotates around the pin is located near the inner surface of the bush. The pin is fixed to the bush, the wheel does not contact the bush, and the portion of the wheel near the center of the bush is A plurality of wheel bearing units are mounted so that they protrude toward the center from the inner surface of the bush and are exposed, and a plurality of wheel bearing units are arranged side by side on the bush. A row of the aligning units is formed, and a flat portion parallel to the central axis of the guide is formed on a side surface of the guide, and each wheel of the wheel bearing unit row rotates while traveling in contact with the corresponding flat portion. Linear motion bearing. 3. A bearing in which a cylindrical guide is inserted into the hollow portion of a hollow cylindrical bush, and the bush is guided by the guide and the bush moves linearly along the center axis of the guide. A cylindrical pin is inserted into the hollow portion through a sliding body, and the wheel bearing unit in which the wheel rotates around the pin is located near the inner surface of the bush, and the center axis of the pin is the bush. The pin is fixed to the bush, the wheel does not contact the bush, and the portion of the wheel closer to the center of the bush is centered from the inner surface of the bush. A plurality of wheel bearing units are protruded and exposed to the side, and a plurality of wheel bearing units are A linear motion bearing in which a row is formed, and a flat portion parallel to the central axis of the guide is formed on a side surface of the guide, and each wheel of the wheel bearing unit row rotates and runs in contact with the corresponding flat portion. 4. A bearing in which a cylindrical guide is inserted into a hollow portion of a hollow cylindrical bush having a notch, and the bush is guided by the guide and the bush moves linearly along a central axis of the guide. A cylindrical pin is inserted into the hollow portion of the shaped wheel via a sliding body, and the wheel bearing unit, which rotates the wheel around the pin, is positioned near the inner surface of the bush, at the center of the pin. The shaft is arranged so as to face the circumferential direction of the bush, the pin is fixed to the bush, the wheel does not contact the bush, and the portion of the wheel near the center of the bush is the bush. Protruding toward the center from the inner surface of the
The bearing units are arranged on the side line of the bush to form a row of wheel bearing units, and a flat portion parallel to the central axis of the guide is formed on a side surface of the guide, and each of the rows of the wheel bearing unit row is formed. The wheel is a linear motion bearing that rotates and runs in contact with the corresponding flat part. 5. The linear motion bearing according to claim 1, wherein the rolling element is a ball bearing. 6. The linear motion bearing according to claim 1, wherein the rolling element is a needle bearing. 7. The linear motion bearing according to claim 3, wherein a disk-shaped or annular projection is formed on a surface of the sliding body. 8. The linear motion bearing according to claim 3, wherein a linear projection extending in a circumferential direction of the pin is formed on a surface of the sliding body. 9. A sliding body comprising an oil-impregnated alloy, a carbon fiber-containing resin,
The linear motion bearing according to claim 3, 4, 8, or 9, which is manufactured from glass fiber-containing resin, hard rubber, plastics, or ceramics. 10. An n-row flat portion is formed on the side surface of the guide point-symmetrically at an angular interval of 360 / n ° around the central axis of the guide, and the inner surface of the bush corresponds to the flat portion.
10. Linear motion bearing according to claim 1, wherein the rows of rows of wheel bearing units are arranged point-symmetrically at an angular spacing of 360 / n.degree. Around the central axis of the bush. 11. The wheel bearing unit according to claim 1, further comprising a position adjuster for finely adjusting the radial position of the bush for the row of the wheel bearing units.
The linear motion bearing according to any one of the above. 12. The linear motion bearing according to claim 11, wherein, for a row of wheel bearing units, a position adjuster for finely adjusting the radial position of the bush is mounted near both ends of the wheel bearing unit. . 13. The apparatus according to claim 2, wherein the plurality of guides are arranged on a straight line with their respective central axes aligned.
The linear motion bearing according to 4, 5, 6, 7, 8, 9, 10, 11 or 12. 14. The linear motion bearing according to claim 1, wherein the guide is made of a hard metal.