Actuator

Abstract

The present invention provides an actuator that can avoid an increase in the working resistance of a ball even when a guide rail is bent or warped, and can achieve miniaturization and weight reduction. The actuator (10) includes a main body (18) and a sliding member (40). A main body side rail groove (90) is formed in the side wall portion (22, 23) constituting the main body (18). On the other hand, a sliding member side rail groove (128) is formed in the sliding member (40). A main body side rail groove (90) and a sliding member side rail groove (128) are provided with a main body side guide rail (100) and a sliding member side guide rail (140). Arc grooves (152, 154) serving as ball grooves are formed by the main body side ball bearing portions (114, 116) of the main body side guide rail (100) and the sliding member side ball bearing portions (146, 148) of the sliding member side guide rail (140).

Description

Technical Field

[0001] The present invention relates to an actuator having a body and a slide moving in an interior space within the body. Background Art

[0002] An actuator having a main body and a slide member moving in an internal space of the main body is widely used as a conveying mechanism for conveying a workpiece, for example. In such an actuator, a worktable is provided on the slide member, and the workpiece is held on the worktable. As the slide member moves integrally with the worktable, the workpiece is conveyed.

[0003] The main body and the sliding member are respectively provided with a ball groove having a substantially semicircular cross section orthogonal to the moving direction of the sliding member, and a ball made of bearing steel or the like is inserted into the ball groove. The sliding member moves smoothly due to the rolling of the ball in the ball groove. In addition, a circulation passage for circulating the ball is formed in the sliding member. After rolling in the ball groove, the ball returns to the ball groove via the circulation passage.

[0004] The ball groove is generally formed by cutting off a part of the main body and the sliding member. In contrast, as described in Japanese Patent Publication No. 2010-138981 and Japanese Patent Publication No. 2014-126190, guide rails facing each other are sometimes provided on the main body and the sliding member. In this case, track grooves are formed on the main body and the sliding member, respectively, and guide rails with ball grooves pre-formed are fitted into each track groove. In the techniques described in Japanese Patent Publication No. 2010-138981 and Japanese Patent Publication No. 2014-126190, the so-called "riveting" is then performed to extrude the parts (walls) of the main body and the sliding member near the guide rail groove toward the guide rail side to prevent the guide rail from falling off the track groove.

[0005] Recently, attempts have been made to reduce the weight of the actuator. To achieve this goal, it is considered effective to form the main body or the sliding member with light metal. In this case, in the prior art in which the ball groove is formed by cutting the main body and the sliding member, there is a concern that sufficient rigidity cannot be ensured near the ball groove.

[0006] From this point of view, the guide rails described in Japanese Patent Application Laid-Open No. 2010-138981 and Japanese Patent Application Laid-Open No. 2014-126190 are made of a metal material having sufficient rigidity. Here, in the actuators described in Japanese Patent Application Laid-Open No. 2010-138981 and Japanese Patent Application Laid-Open No. 2014-126190, two guide rails facing each other form a Gothic arch groove. In this case, when the guide rails are bent or warped, there is a disadvantage that the working resistance of the ball increases. Summary of the invention

[0007] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an actuator that can avoid an increase in the working resistance of the ball even when a guide rail is bent or warped, and can be made smaller and lighter.

[0008] In order to achieve the above-mentioned object, according to one embodiment of the present invention, there is provided an actuator, comprising:

[0009] A main body, the main body comprising a base, and a first side wall portion and a second side wall portion disposed on the base and opposite to each other, wherein an internal space is divided by the base, the first side wall portion and the second side wall portion;

[0010] a sliding member having a portion that moves within the internal space; and

[0011] a workbench, which is disposed on the sliding member and exposed from the inner space,

[0012] The first side wall portion and the second side wall portion are respectively formed with main body side rail grooves on their surfaces facing the internal space.

[0013] Slider side rail grooves are formed on the surfaces of the sliders facing the body side rail grooves, respectively.

[0014] A main body side guide rail is provided in the main body side rail groove, and a slider side guide rail is provided in the slider side rail groove,

[0015] The main body side guide rail comprises: a main body side rail receiving portion, which is received in the main body side rail groove; and a main body side ball bearing portion, which is exposed from the main body side rail groove and is bent into an arc shape.

[0016] The slide-side guide rail comprises: a slide-side rail receiving portion, which is received in the slide-side rail groove; and a slide-side ball bearing portion, which is exposed from the slide-side rail groove and forms an arc groove together with the main body side ball bearing portion.

[0017] The arc groove holds a ball, and the sliding member is provided with a circulation passage for circulating the ball.

[0018] A dimension of the slider-side rail in a vertical direction perpendicular to a moving direction of the slider is larger than a dimension of the body-side rail in a vertical direction perpendicular to the moving direction of the slider.

[0019] According to the present invention, the arc groove formed by a set of main body side rails and slide side rails is used as a ball groove. Therefore, even if the main body side rail or the slide side rail is bent or warped, the increase in the working resistance of the ball can be suppressed compared with the case where the ball groove is formed by a Gothic arch groove.

[0020] In addition, the main body side rail is set to a smaller size than the slider side rail. Therefore, the main body provided with the main body side rail can be miniaturized. Moreover, corresponding to the miniaturization of the main body, it is also possible to achieve weight reduction.

[0021] The above-mentioned objects, features and advantages will be easily understood from the following description of the embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic overall perspective view of an actuator according to a first embodiment of the present invention.

[0023] Figure 2 yes Figure 1 Observe the cross-sectional view in the direction of the arrow on line II-II.

[0024] Figure 3 It is composed Figure 1 A side cross-sectional view of the main parts of the linear guide of the actuator.

[0025] Figure 4 yes Figure 2 An enlarged view of the main part.

[0026] Figure 5 yes Figure 2 Observe the cross-sectional view in the direction of the VV line arrow.

[0027] Figure 6 This is a front cross-sectional view of the main parts of the actuator in which a step portion is provided on the main body side rail and no inclined portion is formed on the slider.

[0028] Figure 7 It is a front cross-sectional view of the main parts showing a state where the main body is caulked by the caulking roller.

[0029] Figure 8 It is a schematic overall perspective view of an actuator according to a second embodiment of the present invention.

[0030] Fig. 9 yes Figure 8 Observe the cross-sectional view in the direction of the arrow on line IX-IX.

[0031] Fig.10 yes Figure 8 An enlarged view of the main part.

[0032] Fig.11 is from Fig. 9 A front cross-sectional view showing a state in which the first protection wall portion and the second protection wall portion are removed.

[0033] Fig.12 is from Fig.10 This is a front cross-sectional view showing a state where a sliding member has been replaced with another sliding member. DETAILED DESCRIPTION

[0034] Hereinafter, preferred embodiments are listed and the actuator according to the present invention is described in detail with reference to the accompanying drawings. Figure 1 The direction away from the motor 14 shown in the figure, "rear" means the direction approaching the motor 14. In addition, "down" and "up" are vertical directions perpendicular to the front-back direction. And, "width direction" is a horizontal direction perpendicular to the front-back direction. Although the above directions are shown in each of the drawings, these directions are for the convenience of simplifying the description and making it easier to understand, and do not particularly specify the directions when the actuator is actually used.

[0035] Figure 1 1 is a schematic overall perspective view of the actuator 10 according to the first embodiment. The actuator 10 is configured as a linear actuator including a linear guide 12 extending in the front-rear direction.

[0036] The actuator 10 includes a motor 14 as a driving unit and a feed screw shaft 16 (see FIG. Figure 2 ). That is, the actuator 10 is an electric actuator. The motor 14 is housed in the motor cover 17. On the other hand, the feed screw shaft 16 extends in the front-to-back direction and is connected to the motor shaft (not shown) via a coupling, for example. Alternatively, the motor shaft itself can be used as the feed screw shaft 16. In this case, a coupling is not required.

[0037] The linear guide 12 includes a main body 18 extending along the axial direction of the feed screw shaft 16, that is, the front-rear direction. Figure 2 As shown, the main body 18 has a base 20 constituting a substantially flat and elongated bottom, and a thick first side wall 22 and a second side wall 23 erected on the upper surface of the base 20. In the first embodiment, the main body 18 further includes a first protective wall 24 integrally connected to the first side wall 22 and a second protective wall 25 integrally connected to the second side wall 23. The first protective wall 24 and the second protective wall 25 extend upward (towards the workbench 46 described later).

[0038] The first protective wall portion 24 protrudes from the upper end of the inner edge portion of the first side wall portion 22 so as to be closer to the second side wall portion 23 than the first side wall portion 22. On the other hand, the second protective wall portion 25 protrudes from the upper end of the inner edge portion of the second side wall portion 23 so as to be closer to the first side wall portion 22 than the second side wall portion 23. Therefore, the separation distance between the first protective wall portion 24 and the second protective wall portion 25 is smaller than the separation distance between the first side wall portion and the second side wall portion.

[0039] The first protection wall 24 has a groove 26 formed in the middle of the first side wall 22 toward the workbench 46, which is recessed toward the second protection wall 25. Similarly, the second protection wall 25 has a groove 26 formed in the middle of the second side wall 23 toward the workbench 46, which is recessed toward the first protection wall 24.

[0040] At the front end and the rear end of the base 20 as the end in the moving direction, a first end plate 27 and a second end plate 28 are provided from the first side wall 22 to the second side wall 23 (see Figure 1 ). In addition, a sealing tape 30 is provided on the upper surfaces of the first side wall portion 22 and the second side wall portion 23 from the first end plate 27 to the second end plate 28 to close the upper opening between the first side wall portion 22 and the second side wall portion 23. Figure 2 As shown, an internal space 32 surrounded by the base 20, the first side wall 22, the second side wall 23, the first protective wall 24, the second protective wall 25, the first end plate 27, the second end plate 28 and the sealing band 30 is defined in the main body 18. The two grooves 26 are both recessed toward the internal space 32.

[0041] The second end plate 28 (see FIG. 2 ) of the main body 18 that closes the rear opening leading to the interior space 32. Figure 1 ) is formed with an insertion hole (not shown) for passing the feed screw shaft 16. On the other hand, the front first end plate 27 closes the front opening leading to the internal space 32. The first end plate 27 and the second end plate 28 are connected to the main body 18 via connecting screws 34.

[0042] In the inner space 32 (ref. Figure 2 ) accommodates a slider body 42 constituting the slider 40. In addition to the slider body 42, the slider 40 also has a neck 44 extending from the slider body 42 and a workbench 46 provided at the top of the neck 44. The workbench 46 is exposed from the internal space 32 and is located above the sealing belt 30.

[0043] A circular nut placement hole 50 is formed in the slider body 42. A cylindrical displacement nut 52 threadedly engaged with the feed screw shaft 16 is placed in the nut placement hole 50. The displacement nut 52 is displaced in the axial direction of the feed screw shaft 16 as the feed screw shaft 16 rotates.

[0044] The table 46 is formed wider than the slider body 42. The table 46 has a substantially U-shaped front cross section along the width direction having a bottom and two sides. A concave space 54 defined between the bottom and the two sides is closed by a flat cover 56.

[0045] As shown in the side cross-sectional view of the main part of the linear guide 12 Figure 3 As shown, the bottom of the workbench 46 is composed of a front inclined portion 60, a thickest portion 62, and a rear inclined portion 64. The front inclined portion 60 is gently inclined upward as it moves from the front to the rear, the top surface of the thickest portion 62 is flat and the wall thickness is the largest at the bottom, and the rear inclined portion 64 is gently inclined downward as it moves from the front to the rear. The bottom of the workbench 46 is roughly trapezoidal in shape when viewed from the side. A guide plate 66 with a rounded top surface is provided in the thickest portion 62. A pair of pin holes 68 are formed in the thickest portion 62 toward the slider body 42, and an insertion pin portion 70 is protrudingly formed on the lower surface of the guide plate 66 (see Figure 2 ). The guide plate 66 is positioned and fixed by inserting the pin portion 70 and fitting it into the pin hole 68.

[0046] In addition, a bolt insertion hole 72 is formed in the rear inclined portion 64 (see Figure 3 On the other hand, the displacement nut 52 is formed with an internal thread hole 74 at a position corresponding to the position of the bolt insertion hole 72. The displacement nut 52 is connected to the slider 40 by screwing a stud bolt 76 for connection through the bolt insertion hole 72 into the internal thread hole 74.

[0047] A front slit 78 and a rear slit 80 are formed between the front end of the table 46 and the front inclined portion 60, and between the rear inclined portion 64 and the rear end of the table 46, respectively. When the slider 40 is displaced (slid) relative to the body 18, the portion of the sealing belt 30 close to the table 46 passes through the front slit 78 and climbs onto the front inclined portion 60, passes through the thickest portion 62 and the rear inclined portion 64, and passes through the rear slit 80. That is, the portion of the sealing belt 30 near the table 46 enters the concave space 54. Therefore, the displaced slider 40 does not interfere with the sealing belt 30.

[0048] In addition, the portion of the sealing tape 30 corresponding to the position of the thickest portion 62 is placed on the rounded top surface of the guide plate 66. This can prevent the sealing tape 30 from bending and cracking. In addition, the sealing tape 30 is pressed by a pressing roller (not shown) held in a roller holding hole 82 formed on the lower surface of the worktable 46.

[0049] A plurality of mounting holes 84 are formed on the upper surface of the table 46 . A workpiece (not shown) is held on the upper surface of the table 46 via mounting bolts (not shown) screwed into the mounting holes 84 .

[0050] like Figure 2 As shown, a plurality of first balls 86 and second balls 88 made of bearing steel or the like and arranged vertically are inserted between the first side wall portion 22 and the slider 40 and between the slider 40 and the second side wall portion 23. This structure will be described.

[0051] like Figure 4 As shown in detail in FIG, near the lower end of the first side wall portion 22, a main body side rail groove 90 extending in the front-to-rear direction is formed on the inner surface facing the internal space 32. The main body side rail groove 90 is open in a manner facing the internal space 32, and is recessed in a direction away from the internal space 32 (outward in the width direction). Therefore, the bottom surface 92 of the main body side rail groove 90 is a vertical surface along the up-down direction. In addition, the side surfaces of the main body side rail groove 90 are a lower horizontal surface 94 and an upper horizontal surface 96 from the opening toward the bottom surface 92. The corner between the bottom surface 92 and the lower horizontal surface 94, and the corner between the bottom surface 92 and the upper horizontal surface 96 are chamfered.

[0052] A concave portion 98 that is recessed outward in the width direction is formed on the bottom surface 92 of the body-side rail groove 90. The concave portion 98 may be filled with an adhesive for holding a body-side guide rail 100 described later.

[0053] A first notch 102 and a second notch 104 are formed near the main body side rail groove 90 of the first side wall portion 22 so as to sandwich the main body side rail groove 90 from top to bottom. The first notch 102 and the second notch 104 extend in the front-to-back direction similarly to the main body side rail groove 90 and are substantially parallel to the main body side rail groove 90. The first notch 102 and the second notch 104 are formed as a caulking roller 106 (see FIG. 1 ) as described later. Figure 7 )'s moving trajectory.

[0054] The main body side rail 100 is provided in the main body side rail groove 90. The portion (wall) near the main body side rail groove 90 of the first side wall portion 22 is pushed toward the main body side rail groove 90, thereby preventing the main body side rail 100 from falling out of the main body side rail groove 90. That is, the main body side rail 100 is held in the main body side rail groove 90 by riveting the main body 18. This will be described later.

[0055] The main body side guide rail 100 has a main body side rail receiving portion 110 received in the main body side rail groove 90 and a main body side rail exposed portion 112 exposed from the main body side rail groove 90. The main body side rail exposed portion 112 includes a first ball support portion 114 and a second ball support portion 116 (both main body side ball support portions) in an arc shape of approximately 1 / 4 of a perfect circle. In addition, a protruding portion 118 protruding toward the slider body 42 is sandwiched between the first ball support portion 114 and the second ball support portion 116. The protruding portion 118 enters between the first ball 86 and the second ball 88, thereby forming a predetermined gap between the first ball 86 and the second ball 88.

[0056] Furthermore, the first and second inclined surfaces 120 and 122 that approach each other as they move from the main body side rail receiving portion 110 toward the first and second ball supporting portions 114 and 116 are formed between the first and second ball supporting portions 114 and 116 and the main body side rail receiving portion 110. With the first and second inclined surfaces 120 and 122 interposed therebetween, the wall thickness between the first and second ball supporting portions 114 and 116 and the main body side rail receiving portion 110 gradually changes. Specifically, the wall thickness of the main body side rail groove 90 decreases as it moves from the main body side rail receiving portion 110 toward the first and second ball supporting portions 114 and 116.

[0057] On the other hand, a slide-side rail groove 128 is formed at a position of the slide 40 opposite to the main body-side rail groove 90. That is, the slide-side rail groove 128 is open to face the main body-side rail groove 90 and is recessed in a direction away from the internal space 32 (inward in the width direction). Therefore, the bottom surface 130 of the slide-side rail groove 128 is also a vertical surface along the up-down direction, and the lower horizontal surface 132 and the upper horizontal surface 134 from the opening to the bottom surface 130 are side surfaces. The corners between the bottom surface 130 and the lower horizontal surface 132 and the corners between the bottom surface 130 and the upper horizontal surface 134 are chamfered.

[0058] A concave portion 136 that is recessed inward in the width direction may be formed in the bottom surface 130 of the slider-side rail groove 128. The concave portion 136 may also be filled with an adhesive for holding the slider-side guide rail 140.

[0059] The sliding member side guide rail 140 is provided in the sliding member side rail groove 128. The height dimension of the opening of the sliding member side rail groove 128 is substantially equal to the height dimension of the sliding member side guide rail 140 (substantially the same dimension as H2 described later). Furthermore, after the sliding member side guide rail 140 is engaged with the sliding member side rail groove 128, the inclined portion 164 described later is riveted in a manner of being flattened toward the sliding member side rail groove 128. By this riveting, the sliding member side guide rail 140 is retained in the sliding member side rail groove 128, and the sliding member side guide rail 140 is prevented from falling off from the sliding member side rail groove 128.

[0060] The slider side guide rail 140 has a slider side rail receiving portion 142 received in the slider side rail groove 128 and a slider side rail exposed portion 144 exposed from the slider side rail groove 128. The slider side rail exposed portion 144 includes a third ball bearing portion 146 and a fourth ball bearing portion 148 (both slider side ball bearing portions) in an arc shape of approximately 1 / 4 of a perfect circle. The third ball bearing portion 146 is opposite to the first ball bearing portion 114, and the fourth ball bearing portion 148 is opposite to the second ball bearing portion 116. The flat portion 150 is interposed between the third ball bearing portion 146 and the fourth ball bearing portion 148.

[0061] Here, the height dimension H2 of the slider side rail 140 (direction orthogonal to the moving direction of the slider 40) is larger than the height dimension H1 of the body side rail 100. Therefore, the third ball support portion 146 is located below the first ball support portion 114, and the fourth ball support portion 148 is located above the second ball support portion 116. As a result of the first ball support portion 114 and the third ball support portion 146, and the second ball support portion 116 and the fourth ball support portion 148 being in such a positional relationship, the first arc groove 152 is formed by the first ball support portion 114 and the third ball support portion 146, and the second arc groove 154 is formed by the second ball support portion 116 and the fourth ball support portion 148.

[0062] That is, in the first embodiment, two arc grooves (first arc groove 152 and second arc groove 154) are formed in an upper and lower arrangement. The first ball 86 and the second ball 88 roll in the first arc groove 152 and the second arc groove 154, respectively. That is, both the first arc groove 152 and the second arc groove 154 are ball grooves.

[0063] In the slider side rail receiving portion 142 constituting the slider side guide rail 140, a first recessed portion 160 and a second recessed portion 162 are respectively formed on the surfaces facing the side surfaces (the lower horizontal surface 132 and the upper horizontal surface 134) of the slider side rail groove 128, namely, the lower surface 156 and the upper surface 158. The first recessed portion 160 is a concave shape facing upward, and the second recessed portion 162 is a concave shape facing downward. These first recessed portions 160 and the second recessed portions 162 are formed before the slider side guide rail 140 is engaged with the slider side rail groove 128. Parts of the first recessed portion 160 and the second recessed portion 162 may also be exposed from the slider side rail groove 128.

[0064] The portion of the slider 40 where the slider side rail groove 128 is formed is an inclined portion 164 whose thickness decreases as it approaches the opening from the bottom surface 130 of the slider side rail groove 128. That is, the wall thickness of the inclined portion 164 is smallest near the opening of the slider side rail groove 128. The top end of the inclined portion 164 is bent toward the first recessed portion 160 and the second recessed portion 162, and thus enters the first recessed portion 160 and the second recessed portion 162.

[0065] In addition, the slider body 42 is provided with a first circulation passage 166 and a second circulation passage 168 (see Figure 2 ). Moreover, at the front and rear of the slider body 42, as shown in FIG. Figure 5 As shown, a first return cover 170 and a second return cover 172 are provided respectively. Specifically, a stopper hole 174 and a threaded through hole 176 connected to the stopper hole 174 are formed in the first return cover 170 and the second return cover 172. Moreover, the main body of the mounting screw 178 passes through the screw through hole 176 and is screwed with the screw hole 180 formed in the slider body 42. Through this screwing, the first return cover 170 and the second return cover 172 are mounted on the slider body 42. In addition, the head of the mounting screw 178 is blocked by the bottom surface of the stopper hole 174.

[0066] The first return cover 170 is formed with a first U-shaped path (not shown) communicating with the first arc groove 152 and the first circulation passage 166, and a second U-shaped path 182 communicating with the second arc groove 154 and the second circulation passage 168. Similarly, the second return cover 172 is formed with a third U-shaped path (not shown) communicating with the first arc groove 152 and the first circulation passage 166, and a fourth U-shaped path 184 communicating with the second arc groove 154 and the second circulation passage 168. The first U-shaped path and the third U-shaped path are located below the second U-shaped path 182 and the fourth U-shaped path 184, respectively.

[0067] The first ball 86 rolling in the first arc groove 152 passes through the first U-shaped path or the third U-shaped path and returns to the first arc groove 152 through the first circulation path 166. Similarly, the second ball 88 rolling in the second arc groove 154 passes through the second U-shaped path 182 or the fourth U-shaped path 184 and returns to the second arc groove 154 through the second circulation path 168. By repeating this process, the first ball 86 and the second ball 88 circulate.

[0068] The above-mentioned structure is also the same in the slider main body 42 and the second side wall portion 23. Therefore, the same reference numerals are attached to the same components as the above-mentioned components, and the detailed description thereof will be omitted.

[0069] In the first embodiment, the main body 18 and the slider 40 are made of light metal. As a preferred example of light metal, aluminum or aluminum alloy, which is particularly light, inexpensive, and easy to form, can be cited. On the other hand, the main body side rail 100 and the slider side rail 140 are made of a metal material with excellent rigidity. As a specific example of such a metal material, iron-based metals such as stainless steel can be cited. Aluminum or aluminum alloys and stainless steel have the advantage of good corrosion resistance.

[0070] also, Figure 2 Reference numeral 186 in the figure denotes a dust collecting pipe for sucking dust and the like generated in the internal space 32 and discharging it to the outside of the actuator 10 .

[0071] The actuator 10 according to the first embodiment is basically configured including the linear guide 12 configured as described above, and the operation and effect thereof will be described below.

[0072] In the manufacturing process of the actuator 10, the main body side rail 100 and the slider side rail 140 are manufactured by drawing, rolling, etc. Figure 6 When the step portion 190 is provided between the main body side rail receiving portion 110a and the first ball support portion 114a and the second ball support portion 116a, as shown in FIG. 1 , the shape becomes complicated. It is difficult to produce the main body side rail 100a of such a shape by drawing, rolling, etc. Figure 4 As shown, the first inclined surface 120 and the second inclined surface 122 are provided between the main body side rail receiving portion 110 and the first ball support portion 114 and the second ball support portion 116, thereby making the main body side rail 100 have a simple shape. Moreover, the main body side rail 100 can be easily obtained by drawing, rolling, etc.

[0073] The main body side rail receiving portion 110 of the main body side guide rail 100 is fitted into the main body side rail groove 90 formed in advance in the first side wall portion 22 and the second side wall portion 23 constituting the main body 18. As described above, the recessed portion 98 may be filled with an adhesive in advance.

[0074] Then, if Figure 7 As shown, a riveting roller 106 is used. That is, the riveting roller 106 is pressed below the main body side track groove 90 on the front end side (or rear end side) of the inner surface of the first side wall portion 22 to apply pressure. The inner surface of the first side wall portion 22 is plastically deformed by the riveting roller 106 accompanied by the pressurizing action. That is, the riveting roller 106 biting into the inner surface of the first side wall portion 22 is displaced parallel to the main body side track groove 90, so that a part of the wall of the inner surface is squeezed out toward the main body side track groove 90 upward. As a result, the first notch 102 is formed as a moving track mark of the riveting roller 106.

[0075] The main body side rail 100 is pressed against the upper horizontal surface 96 by the wall protruding toward the main body side rail groove 90. Therefore, the main body side rail 100 is difficult to fall off from the main body side rail groove 90.

[0076] Preferably, the riveting roller 106 is moved to a position slightly above the main body side track groove 90, and the riveting roller 106 is bitten into the inner surface in the same manner as described above to displace the riveting roller 106 in parallel with the main body side track groove 90. As a result, a portion of the wall of the inner surface is extruded toward the main body side track groove 90 below, and a second notch 104 is formed as a moving track of the riveting roller 106. In this case, the main body side guide rail 100 is pressed toward the lower horizontal surface 94 by the wall extruded toward the main body side track groove 90. That is, the main body side guide rail 100 is clamped by the extruded walls. Therefore, it is more difficult for the main body side guide rail 100 to fall off from the main body side track groove 90.

[0077] On the other hand, the slider-side rail receiving portion 142 of the slider-side guide rail 140 is fitted into the slider-side rail groove 128 formed in advance in the slider body 42. As described above, the recessed portion 136 may be filled with an adhesive in advance.

[0078] Here, in Figure 6 The slider side guide rail 140a without the first recessed portion 160 and the second recessed portion 162 and the slider body 42a without the inclined portion 164 are also shown. In this case, the slider side guide rail 140a and the slider body 42a have relatively poor elasticity. Therefore, when the slider side guide rail 140a is fitted into the slider side rail groove 128, a large pressing force is required.

[0079] In addition, in this structure, the portion of the slider body 42a near the slider side rail groove 128a is thick-walled, so a portion of the slider body 42a cannot be bent toward the lower surface 156a and the upper surface 158a of the slider side guide rail 140a. In this case, if a portion (slider side rail exposed portion) exposed from the slider side rail groove 128a is provided on the slider side guide rail 140a, the contact area between the side surface of the slider side rail groove 128a and the slider side guide rail 140a becomes smaller, so there is a concern that the slider side guide rail 140a may fall off from the slider side rail groove 128a.

[0080] To prevent falling off, Figure 6 As shown, it is sufficient to accommodate the entire slide side guide rail 140a in the slide side rail groove 128a. However, to do this, it is necessary to make the portion forming the slide side rail groove 128a bulge outward in the width direction. Therefore, in this case, it is not easy to reduce the width direction dimension of the slide body 42a.

[0081] In contrast, in the first embodiment, the first recessed portion 160 and the second recessed portion 162 are formed on the lower surface 156 and the upper surface 158 of the side surfaces (lower horizontal surface 132 and upper horizontal surface 134) of the slider-side rail receiving portion 142 facing the slider-side rail groove 128 (see Figure 2 and Figure 4 ). As long as the top of the inclined portion 164 is riveted in a manner of being flattened and entering the first recessed portion 160 and the second recessed portion 162, the top of the inclined portion 164 becomes a stopper that blocks the slider side guide rail 140. That is, the slider side guide rail 140 is prevented from falling off from the slider side rail groove 128.

[0082] Therefore, in this case, even if the contact area between the side surface of the slider-side rail groove 128 and the slider-side guide rail 140 is reduced, the slider-side guide rail 140 can be held in the slider-side rail groove 128. Accordingly, the slider body 42 can be miniaturized in the width direction.

[0083] Furthermore, in the first embodiment, the portion of the slider body 42 near the slider side rail groove 128 is provided as the inclined portion 164. Therefore, the wall thickness of the slider body 42 is small near the opening of the slider side rail groove 128. Therefore, after the slider side guide rail 140 is fitted into the slider side rail groove 128, the portion of the inclined portion 164 near the opening of the slider side rail groove 128 can be easily flattened (riveted) by pointing it toward the slider side rail groove 128.

[0084] For the reasons described above, it is possible to reduce the pressing force applied to the inclined portion 164 when the inclined portion 164 is crushed (caulked). That is, the caulking work becomes easy.

[0085] In addition, when the main body 18 is provided with a guide rail having the same shape as the slider side guide rail 140, and the slider 40 is provided with a guide rail having the same shape as the main body side guide rail 100, the height direction dimension of the first side wall portion 22 and the second side wall portion 23 becomes larger. This is because, as described above, the height direction dimension H2 of the slider side guide rail 140 is larger than the height direction dimension H1 of the main body side guide rail 100.

[0086] In contrast, in the first embodiment, the guide rail having a large height dimension (i.e., the slider side guide rail 140) is provided on the slider 40 side. Therefore, the height dimension of the first side wall portion 22 and the second side wall portion 23 can be reduced as much as possible. That is, the height dimension of the main body 18 can be reduced.

[0087] For the reasons described above, it is possible to reduce the size of the linear guide 12. Furthermore, it is possible to reduce the size of the linear guide 12, and accordingly, it is possible to reduce the weight of the actuator 10.

[0088] As described above, the first and second circular arc grooves 152 and 154 are formed by the first and second ball bearings 114 and 116 of the body side rail 100 and the third and fourth ball bearings 146 and 148 of the slider side rail 140. The first and second balls 86 and 88 are respectively accommodated in the first and second circular arc grooves 152 and 154 in a rollable manner.

[0089] When the assembled actuator 10 is operated, a predetermined workpiece is held via the mounting bolts screwed into the mounting holes 84 of the table 46. Furthermore, power is supplied to the motor 14 from a power source (not shown). As a result, the motor shaft and the feed screw shaft 16 rotate, and the displacement nut 52 screwed into the feed screw shaft 16 moves forward or backward.

[0090] The displacement nut 52 is connected to the stud bolt 76 (see Figure 3 ) is connected to the slider 40. Therefore, the slider 40 moves in the internal space 32 together with the displacement nut 52, and reaches the front end or rear end of the main body 18 to reach the displacement terminal position. Of course, the slider main body 42 moves in the internal space 32 in the main body 18. In addition, the workpiece held on the workbench 46 exposed outside the internal space 32 is transported to the front end or rear end of the main body 18.

[0091] During this period, the first ball 86 rolls in the first arc groove 152. The first ball 86 that has finished rolling in the first arc groove 152 returns to the first arc groove 152 via the first U-shaped path formed in the first return cover 170 (or the third U-shaped path formed in the second return cover 172) and the first circulation path 166 formed in the slider body 42. Similarly, the second ball 88 circulates in the second arc groove 154 and the second circulation path 168 via the second U-shaped path 182 (or the fourth U-shaped path 184).

[0092] The first arc groove 152 and the second arc groove 154 have the advantage of suppressing the increase in the operating resistance of the first ball 86 and the second ball 88 even if the body-side rail 100 and the slider-side rail 140 are bent or warped. Therefore, according to the first embodiment, the slider 40 can be easily displaced.

[0093] During the above operation, negative pressure is applied to the dust collecting pipe 186 provided in the main body 18. Therefore, dust generated in the internal space 32 (inside the machine body 18) is sucked into the dust collecting pipe 186 and discharged to the outside of the actuator 10 through a negative pressure supply port (not shown).

[0094] Next, refer to Figures 8 to 12 , the actuator 200 (and the actuator 300) involved in the second embodiment will be described.

[0095] The main body 202 in the second embodiment includes: a base 204 constituting a substantially flat and elongated bottom; and a thick first side wall 206 and a second side wall 208 erected on the upper surface of the base 204. Furthermore, by providing a first protective wall 210 and a second protective wall 212 at the upper ends of the inner edges of the first side wall 206 and the second side wall 208, a housing 214 including the main body 202, the first protective wall 210 and the second protective wall 212 is formed (see in particular Fig. 9 ). Thus, in the second embodiment, the first side wall portion 206 and the first protective wall portion 210 are different components, and the second side wall portion 208 and the second protective wall portion 212 are also different components. In other words, in this case, the side portion of the main body 202 is divided into two parts, the side wall portion and the protective wall portion, and the side portion is formed by combining them.

[0096] In more detail, at the upper end of the inner edge of the first side wall portion 206, an engaging claw portion 220 as a first engaging portion is provided in a manner extending in the front-to-back direction. On the other hand, at the lower end of the first protective wall portion 210, an engaging groove 222 is formed in a manner extending in the front-to-back direction and is recessed toward the side (upper) of the workbench 46. The engaging groove 222 is a second engaging portion, and the engaging claw portion 220 is inserted into the engaging groove 222 in a detachable manner. Accompanying the insertion, the engaging claw portion 220 and the engaging groove 222 engage with each other. As a result, the first protective wall portion 210 is detachably connected to and supported by the first side wall portion 206 with respect to the first side wall portion 206. The above structure is also the same for the second side wall portion 208 and the second protective wall portion 212.

[0097] Here, the first protection wall portion 210 and the second protection wall portion 212 are respectively formed with grooves 224 that are recessed toward the inner space 32. On the other hand, the second end plate 28, such as Figure 8 and Fig.10 As shown, two protrusions 226 shorter than the front-rear dimension of the groove 224 are provided on the end surface on the side facing the main body 202. The protrusions 226 are, for example, formed by a pin whose one end is inserted into a bottomed hole formed in the main body 202. Alternatively, a pin-shaped portion provided integrally with the second end plate 28 may be used as the protrusion 226.

[0098] The protrusion 226 enters the groove 224. And, the protrusion 226 abuts against the lower surface of the groove 224 (see Fig. 9 ). Through this abutment, the first protective wall portion 210 and the second protective wall portion 212 are pressed by the protrusion 226. As a result, it is possible to effectively prevent the first protective wall portion 210 from tilting toward the second protective wall portion 212 and the second protective wall portion 212 from tilting toward the first protective wall portion 210. Therefore, it is not particularly necessary to fasten the first side wall portion 206 and the first protective wall portion 210, and the second side wall portion 208 and the second protective wall portion 212 with bolts or the like. However, it is not a problem even if they are fastened with bolts or the like.

[0099] The actuator 200 according to the second embodiment is configured similarly to the actuator 10 according to the first embodiment except for the above-mentioned structure. Therefore, the components other than the above-mentioned components are marked with the same reference numerals as those in the first embodiment. Figure 1 to Figure 5 as well as Figure 7 The same reference numerals are used throughout the text.

[0100] The effects of the actuator 200 are described. First, the actuator 200 can of course achieve the same effects as the actuator 10 involved in the first embodiment. In addition, in the actuator 200, the first side wall portion 206 and the first protective wall portion 210, the second side wall portion 208 and the second protective wall portion 212 are provided as different components, based on which the following effects can be achieved.

[0101] That is, the first protective wall 210 can be attached and detached from the first side wall 206, and the second protective wall 212 can be attached and detached from the second side wall 208. Therefore, when the first ball 86, the second ball 88, or the feed screw shaft 16 is to be supplied with oil after the actuator 200 is repeatedly used, at least one of the first protective wall 210 or the second protective wall 212 can be removed from the first side wall 206 or the second side wall 208. When both the first protective wall 210 and the second protective wall 212 are removed, the actuator 200 is Fig.11 The worker only needs to fill the second ball 88 with oil from between the first side wall and the slider side rail 140, or between the second side wall and the slider side rail 140. Of course, maintenance other than filling with oil, such as cleaning, can also be performed.

[0102] As described above, according to the second embodiment, it is not necessary to perform disassembly such as removing at least one of the first protection wall 210 and the second protection wall 212 from the first side wall 206 and the second side wall 208. Therefore, the actuator 200 can be easily maintained.

[0103] Furthermore, in the case where the sealing tape 30 is not required, Fig.12 As shown, the actuator 300 may be configured without providing the first protective wall 210 and the second protective wall 212 on the main body 202. In this case, the height dimension of the slider 302 can be set to be slightly larger than the height dimension of the first side wall 206 and the second side wall 208. That is, the height dimension of the slider 302 can be made smaller than the slider 40 in correspondence with the absence of the first protective wall 210 and the second protective wall 212.

[0104] As can be understood from this, according to the second embodiment, the main body 202 can accommodate either the slider 40 or the slider 302. That is, the versatility of the main body 202 is improved. In addition, when the slider 302 is adopted, the actuator 300 can be configured as a small actuator with a height smaller than that of the actuators 10 and 200. In addition, in the actuator 300, the internal space 32 is divided by the main body 202, that is, the base 204, the first side wall 206, and the second side wall 208.

[0105] The present invention is not particularly limited to the above-described first embodiment and second embodiment, and various modifications can be made without departing from the gist of the present invention.

[0106] For example, the body-side rail 100 and the slider-side rail 140 may be held in the body-side rail groove 90 and the slider-side rail groove 128 via adhesive. In this case, the first side wall 22, the second side wall 23, or the inclined portion 164 does not need to be caulked.

[0107] Alternatively, the number of the main body-side ball bearing parts and the number of the slider-side ball bearing parts may be one on each side, and the number of the arc grooves formed in the vertical direction may be one on each side.

Claims

1. An actuator, characterized in that: have: A main body (202), the main body comprising a base (204) and a first side wall (206) and a second side wall (208) disposed on the base and opposite to each other, wherein an internal space (32) is divided by the base, the first side wall and the second side wall; a sliding member (40) having a portion that moves within the internal space; as well as a workbench (46) disposed on the sliding member and exposed from the inner space, A main body side rail groove (90) is formed on the surface of the first side wall portion and the second side wall portion facing the internal space, respectively. Slider side rail grooves (128) are formed on the surfaces of the sliders that are opposite to the body side rail grooves. A main body side guide rail (100) is provided in the main body side rail groove, and a slide member side guide rail (140) is provided in the slide member side rail groove, The main body side guide rail comprises: a main body side rail receiving portion (110) received in the main body side rail groove; and a main body side ball bearing portion exposed from the main body side rail groove and bent into an arc shape. The slide member side guide rail comprises: a slide member side rail receiving portion (142) received in the slide member side rail groove; and a slide member side ball bearing portion exposed from the slide member side rail groove and forming an arc groove together with the main body side ball bearing portion. The arc groove holds balls (86, 88), and the sliding member is provided with circulation passages (166, 168) for circulating the balls. The dimension (H2) of the slider-side guide rail in the vertical direction perpendicular to the moving direction of the slider is larger than the dimension (H1) of the body-side guide rail in the vertical direction perpendicular to the moving direction of the slider. The actuator further comprises a first protective wall portion (210) and a second protective wall portion (212), wherein the first protective wall portion and the second protective wall portion are respectively arranged on the first side wall portion and the second side wall portion in a manner extending toward the workbench, and divide the internal space together with the first side wall portion and the second side wall portion. The first protection wall portion is detachably connected to the first side wall portion, and the second protection wall portion is detachably connected to the second side wall portion. The actuator further comprises a first end plate (27) and a second end plate (28) arranged at the end portions of the sliding member in the moving direction. A groove (224) recessed toward the inner space is formed in each of the first protective wall portion and the second protective wall portion at a position midway from the first side wall portion and the second side wall portion to the workbench, and a protrusion (226) entering the groove is provided on the first end plate or the second end plate.

2. The actuator according to claim 1, characterized in that A notch extending in a moving direction of the slider is formed near the main body side rail.

3. The actuator according to claim 2, characterized in that As the notches, a first notch (102) and a second notch (104) are formed to sandwich the main body side rail.

4. The actuator according to claim 1, characterized in that A first recessed portion (160) and a second recessed portion (162) are formed on a surface of the slider-side rail accommodating portion that faces the side surface of the slider-side guide rail.

5. The actuator according to claim 1, characterized in that: The portion of the slider where the slider-side rail groove is formed is an inclined portion (164) whose thickness decreases as it approaches the opening from the bottom surface of the slider-side rail groove.

6. The actuator according to claim 1, characterized in that An inclined surface (120, 122) is formed between the main body side rail receiving portion and the main body side ball support portion of the main body side guide rail, and the inclined surface is inclined in a manner such that the wall thickness of the main body side guide rail decreases as it approaches the main body side ball support portion from the main body side rail receiving portion.

7. The actuator according to claim 1, characterized in that A recessed portion (98) is formed on at least one bottom surface of the main body side rail groove or the slider side rail groove.

8. The actuator according to claim 1, characterized in that The main body side guide rail has a first ball bearing portion (114) and a second ball bearing portion (116) as the main body side ball bearing portion, and has a protruding end portion (118) sandwiched between the first ball bearing portion and the second ball bearing portion and protruding toward the slide member side guide rail. The slide member side guide rail has a third ball bearing portion (146) and a fourth ball bearing portion (148) as the slide member side ball bearing portions. As the arc grooves, a first arc groove (152) between the first ball support portion and the third ball support portion and a second arc groove (154) between the second ball support portion and the fourth ball support portion are formed.

9. The actuator according to claim 1, characterized in that: The main body and the slider are made of light metal, and the main body side rail and the slider side rail are made of iron-based metal.

10. The actuator according to claim 9, characterized in that The main body and the slider are made of aluminum or an aluminum alloy, and the main body side guide rail and the slider side guide rail are made of stainless steel.

11. The actuator according to any one of claims 1 to 10, characterized in that The first side wall portion and the second side wall portion are each provided with a first snap-fit ​​portion (220), and the first protective wall portion and the second protective wall portion are each provided with a second snap-fit ​​portion (222). The first snap-fit ​​portion and the second snap-fit ​​portion are snap-fitted with each other, so that the first protective wall portion and the second protective wall portion are respectively connected to the first side wall portion and the second side wall portion in a manner that allows them to be loaded and unloaded.

Images