Direct-acting guide device

Abstract

The present invention provides a direct-acting guide device that allows for easy provision of a meshing portion that engages with a gear on a guide rail. The direct-acting guide device comprises: two guide rails (2, 3) movable relative to each other along their length by means of at least one rolling element; and a retainer that holds the rolling element and retains a gear (13) engaged with a meshing portion (2b, 3b) provided on at least one of the two guide rails (2, 3) so that it is rotatable. The meshing portion (2b, 3b) has a plurality of circular holes (18) arranged along the length of the guide rails (2, 3). The wall surface (18a) of the circular holes (18) is formed in a cylindrical shape.

Description

Technical Field

[0001] The present invention relates to a direct-acting guide device having a mechanism for preventing positional displacement of the retainer. Background Technology

[0002] A known linear guide device (see Patent Document 1) is equipped with a position offset prevention mechanism to prevent positional deviation of the retainer. This linear guide device has two guide rails that can move relative to each other along the length direction by means of at least one rolling element. The rolling element is held in the retainer.

[0003] In a linear guide device, when two guide rails are repeatedly moved relative to each other, the retainer that holds the rolling elements deviates from its proper position. To prevent this positional deviation, a positional deviation prevention mechanism is provided. This mechanism consists of a rack on the guide rails and a pinion on the retainer. When the two guide rails move relative to each other, the pinion meshes with the rack and moves to its proper position, thus preventing the retainer from deviating from its proper position.

[0004] Furthermore, in the direct-acting guide device described in Patent Document 1, the rack and pinion are formed as involute gears, which are ideal gears. This ensures the strength of the rack and pinion.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Utility Model Application Publication No. 62-179423 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, involute gears have complex shapes, and there is a problem that setting involute gears on guide rails is quite laborious.

[0010] The present invention was made in view of the above-mentioned problems, and its object is to provide a direct-drive guide device that can easily install a meshing part that engages with a gear on a guide rail.

[0011] Solution for solving the problem

[0012] To address the aforementioned issues, one aspect of the present invention is a direct-acting guide device comprising: two guide rails that are movable relative to each other along their length by means of at least one rolling element; and a retainer that holds the rolling element and retains a gear engaged with a meshing portion disposed on at least one of the two guide rails so that it is rotatable. The direct-acting guide device is characterized in that the meshing portion has a plurality of circular holes arranged along the length direction of the guide rails, the walls of the circular holes being formed in a cylindrical shape.

[0013] Invention Effects

[0014] According to the present invention, the meshing part that engages with the gear is provided as a plurality of circular holes, so that the meshing part can be easily provided on the guide rail. Attached Figure Description

[0015] Figure 1 This is a perspective view of a direct-drive guiding device according to an embodiment of the present invention.

[0016] Figure 2 This is an internal structural diagram of the direct-drive guide device in this embodiment.

[0017] Figure 3 This is a perspective view showing the rolling elements and gears of the direct-drive guide device according to this embodiment.

[0018] Figure 4 This is a perspective view showing the guide rail and gear of the direct-acting guide device of this embodiment (a cross-sectional view including the guide rail in part).

[0019] Figure 5 This is a detailed drawing of the guide rail of the direct-acting guide device in this embodiment. Figure 5 (a) is the front view. Figure 5 (b) is Figure 5 (a) bb-line section view.

[0020] Figure 6 This is a detailed drawing of the gears of the direct-acting guide device in this embodiment. Figure 6 (a) is a 3D diagram. Figure 6 (b) is a side view. Figure 6 (c) is the top view.

[0021] Figure 7 This is a diagram showing the circular hole and gear teeth of the direct-acting guide device in this embodiment. Figure 7 (a) shows the state in which the gear teeth begin to enter the circular hole. Figure 7 (b) shows the state in which the tooth tip contacts the wall of the circular hole.

[0022] Figure 8 This is a cross-sectional view of the circular hole and the top of the teeth of the direct-acting guide device in this embodiment.

[0023] Figure 9 This is a cross-sectional view showing other examples of the tooth tip. Detailed Implementation

[0024] Hereinafter, a direct-drive guiding device according to an embodiment of the present invention will be described based on the accompanying drawings. However, the direct-drive guiding device of the present invention can be embodied in various ways and is not limited to the embodiments described in this specification. This embodiment is provided so that those skilled in the art can fully understand the intent of the invention by making the specification sufficiently clear.

[0025] Figure 1 This is a perspective view of a direct-drive guide device 1 according to an embodiment of the present invention. 2 and 3 are guide rails. V-shaped track grooves 4 and 5 are formed on guide rails 2 and 3 respectively. Track groove 4 has mutually perpendicular track surfaces 7a and 7b. Track groove 5 has mutually perpendicular track surfaces 8a and 8b. Guide rails 2 and 3 are connected by rollers 9a and 9b (see reference). Figure 2 They can move relative to each other along the length direction.

[0026] Mounting holes 2a are formed in guide rail 2 for mounting on a base or the like. Mounting holes 3a are formed in guide rail 3 for mounting on a worktable or the like. The shape of guide rail 3 is approximately the same as the shape obtained by reversing guide rail 2 by 180°.

[0027] Figure 2 The text is incomplete and contains errors. A more accurate translation would require the full context. Figure 1 The state of the guide rail 3 on the front side. Figure 3 The text is incomplete and contains errors. A more accurate translation would require the full context. Figure 2 The state of the retainer 10. Rollers 9a and 9b, serving as rolling elements, are arranged between the opposing track grooves 4 and 5 of guide rails 2 and 3. Rollers 9a and 9b are cross rollers with their axes perpendicular to each other. Rollers 9a and 9b are approximately square in side view, and their diameters are slightly larger than their lengths in the axial direction. The side of roller 9a contacts the track surface 7a of guide rail 2 and the track surface 8b of guide rail 3. The side of roller 9b contacts the track surface 7b of guide rail 2 and the track surface 8a of guide rail 3. The force acting on guide rail 2 is transmitted to guide rail 3 via rollers 9a and 9b.

[0028] It should be noted that in this embodiment, a cross roller is used as the rolling element, but a ball bearing or a parallel roller such as a needle roller can also be used as the rolling element.

[0029] like Figure 2 As shown, rollers 9a and 9b are held along guide rails 2 and 3 in a retainer 10 extending in the length direction. A pinion-shaped gear 13 is also held in the retainer 10 in a rotatable manner. The gear 13 is positioned approximately at the center of the retainer 10 in the length direction.

[0030] Figure 4Guide rails 2 and 3 and gear 13 are shown. Clearance grooves 16 and 17 are formed at the bottom of the track grooves 4 and 5 of guide rails 2 and 3. Rack-shaped meshing portions 2b and 3b are formed on the bottom surface of the clearance grooves 16 and 17. The teeth 21 of gear 13 engage with the meshing portions 2b and 3b. The relative position of gear 13 with respect to guide rails 2 and 3 is determined by the relative position of guide rails 2 and 3.

[0031] Figure 5 A detailed view of guide rail 2 is shown. The engaging portion 2b has a plurality of circular holes 18 arranged along the length direction of guide rail 2. The circular holes 18 are arranged at equal intervals along the length direction of guide rail 2. The wall surface 18a of the circular holes 18 is formed into a cylindrical shape. That is, the cross-sectional shape of the circular holes 18 is circular, and the cross-sectional shape of the circular holes 18 is constant in the depth direction. The center line 18c of the circular holes 18 is orthogonal to the length direction of guide rail 2. Guide rail 3 also has a plurality of circular holes 18 formed in the same manner as guide rail 2 (see reference). Figure 4 ).

[0032] The circular hole 18 is formed directly in the guide rails 2 and 3. Furthermore, the circular hole 18 is machined using cutting tools such as a drilling machine or end mill with a flat front end. Moreover, the bottom surface 18b of the circular hole 18 is formed to be flat (see reference). Figure 5 (b) It should be noted that a rack with a round hole can be mounted on a guide rail, or the round hole can be machined by electrical discharge machining, or the bottom surface of the round hole can be formed into a cone shape to match a drilling machine with a conical front end.

[0033] Figure 6 A detailed diagram of gear 13 is shown. (See attached image.) Figure 6 As shown in (a), the gear 13 includes a disk portion 13a with a plurality of teeth 21 formed on its outer periphery and a shaft portion 13b integrally formed with the disk portion 13a. The gear 13 is supported by the retainer 10 so that it can rotate about the shaft portion 13b.

[0034] The gear 13 has teeth 21 having a tooth tip 21a and a tooth root 21b. The tooth tip 21a has a shape that rounds the corners of a cuboid. Figure 6 As shown in (b) and (c), the length L of the tooth tip 21a in the rotational direction R is longer than the tooth width W (length in the direction of the rotation axis) of the tooth tip 21a. It should be noted that in Figure 6 In (c), the tooth tip 21a is shown by a slash.

[0035] like Figure 6 As shown in (b), when viewed in the direction of rotation, the root portion 21b narrows, and the length T of the root portion 21b in the direction of rotation R is shorter than the length L of the tip portion 21a in the direction of rotation R. Figure 7 The circular hole 18 and the tooth 21 of the gear 13 are shown. Figure 7(a) shows the state in which the tooth 21 of gear 13 begins to enter the circular hole 18. Figure 7 (b) shows the state in which the tooth tip 21a contacts the wall surface 18a of the circular hole 18. It should be noted that in Figure 7 In (b), it can be seen that there is a gap between the tooth tip 21a and the wall surface 18a of the circular hole 18, but the tooth tip 21a has a tooth width W along the depth direction of the paper surface (orthogonal direction to the paper surface), so the tooth tip 21a contacts the wall surface 18a of the circular hole 18 at a position closer to the depth side than the paper surface. Figure 7 As shown in (a) and (b), the root portion 21b of tooth 2I is narrowed in a way to avoid interference with the edge portion 18a1 of the circular hole 18.

[0036] Figure 8 A cross-sectional view (orthogonal to the axis of the circular hole 18) of the circular hole 18 and the tooth tip 21a is shown. As described above, the length L in the rotational direction of the tooth tip 21a is longer than the tooth width W of the tooth tip 21a. Therefore, the clearance g1 in the rotational direction between the tooth tip 21a and the wall surface 18a of the circular hole 18 is smaller than the clearance g2 in the rotational axis direction. The clearance g2 is set in a manner that allows the shaft of gear 13 to oscillate (gear 13 to tilt).

[0037] If the length L of the tooth tip 21a in the rotational direction is longer than the tooth width W of the tooth tip 21a, then the clearance g2 is larger than the clearance g1. Therefore, the cross-sectional area of ​​the tooth tip 21a can be increased while allowing the shaft of gear 13 to vibrate, thereby improving the strength of tooth 21. In addition, since the clearance g1 is smaller than the clearance g2, it is possible to prevent gear 13 from moving along the rotational direction (the length direction of guide rails 2 and 3).

[0038] Figure 9 Other examples of the cross-sectional shape of the tooth tip 21a are shown. For example... Figure 9 As shown, the cross-sectional shape of the tooth tip 21a can also be a combination of a rectangle and a semicircle. Alternatively, although not shown, it can also be an elliptical shape.

[0039] The structure of the direct-acting guide device 1 according to this embodiment has been described above. The direct-acting guide device 1 according to this embodiment achieves the following effects.

[0040] The meshing parts 2b and 3b have a plurality of circular holes 18 arranged along the length of the guide rails 2 and 3. The wall surface 18a of the circular holes 18 is formed into a cylindrical shape, so the shape of the meshing parts 2b and 3b that engage with the gear 13 can be simplified, and the meshing parts 2b and 3b can be easily installed on the guide rails 2 and 3.

[0041] The length L of the tooth tip 21a of the gear 13 in the rotational direction is longer than the tooth width W of the tooth tip 21a. Therefore, the clearance g2 can be larger than the clearance g1, which allows for an increase in the cross-sectional area of ​​the tooth tip 21a while allowing for shaft oscillation of the gear 13. In addition, since the clearance g1 is smaller than the clearance g2, it is possible to prevent the gear 13 from moving in the rotational direction.

[0042] When viewed in the direction of the rotation axis of gear 13, the root portion 21b of tooth 21 narrows, thus preventing interference between the edge portion 18a1 of the circular hole 18 and tooth 21.

[0043] The circular hole 18 is formed directly on the guide rails 2 and 3, so the meshing parts 2b and 3b can be easily formed on the guide rails 2 and 3.

[0044] The bottom surface 18b of the circular hole 18 is made flat, thus preventing interference between the circular hole 18 and the mounting holes 2a and 3a of the guide rails 2 and 3.

[0045] The circular holes 18 are machined on guide rails 2 and 3 using cutting tools, thus making it easy to machine the circular holes 18 on guide rails 2 and 3.

[0046] It should be noted that the direct-drive guiding device of this embodiment can be assembled as an essential component in a wide range of fields, from industrial machinery such as machine tools, semiconductor and liquid crystal manufacturing equipment (e.g., assembly machines) and robots, to consumer applications such as system kitchens, various game consoles, medical equipment, food processing equipment, and handling equipment.

[0047] This specification is based on Japanese Patent Application No. 2021-012649, filed on January 29, 2021. Its entire contents are contained herein.

[0048] Explanation of reference numerals in the attached figures

[0049] 1: Direct-acting guide device; 2, 3: Guide rails; 2b, 3b: Meshing parts; 9a, 9b: Rollers (rolling elements); 10: Retainer; 13: Gear; 18: Circular hole; 18a: Wall of the circular hole; 18b: Bottom of the circular hole; 21: Gear tooth; 21a: Tooth tip; 21b: Tooth root; L: Length of the tooth tip in the direction of rotation; W: Tooth width of the tooth tip.

Claims

1. A direct-acting guide device, comprising: Two guide rails, which are movable relative to each other along their length by means of at least one rolling element; and A retainer holds the rolling element and keeps the gear, which engages with the meshing portion of at least one of the two guide rails, rotatable. in, The engaging portion has a plurality of circular holes arranged along the length direction of the guide rail. The wall of the circular hole is formed into a cylindrical shape. The gap (g1) in the rotational direction between the tip of the gear tooth and the wall of the circular hole is smaller than the gap (g2) in the rotational axis direction of the gear.

2. A direct-acting guide device, comprising: Two guide rails, which are movable relative to each other along their length by means of at least one rolling element; and A retainer holds the rolling element and keeps the gear, which engages with the meshing portion of at least one of the two guide rails, rotatable. in, The engaging portion has a plurality of circular holes arranged along the length direction of the guide rail. The wall of the circular hole is formed into a cylindrical shape. The length of the tooth tip in the rotational direction of the gear is longer than the tooth width at the tooth tip.

3. A direct-acting guide device, comprising: Two guide rails, which are movable relative to each other along their length by means of at least one rolling element; and A retainer holds the rolling element and keeps the gear, which engages with the meshing portion of at least one of the two guide rails, rotatable. in, The engaging portion has a plurality of circular holes arranged along the length direction of the guide rail. The wall of the circular hole is formed into a cylindrical shape. When viewed in the direction of the gear's rotation axis, the root of the gear's teeth narrows.

4. The direct-acting guide device according to any one of claims 1 to 3, characterized in that, The circular hole is formed directly in the guide rail.

5. The direct-acting guide device according to any one of claims 1 to 3, characterized in that, The bottom surface of the circular hole is formed to be flat.

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