Gear apparatus, method for manufacturing a gear apparatus

Abstract

This invention has been made in view of the problem of reducing performance variations in conventional gear devices, and one of its objectives is to provide a gear device that can reduce performance variations caused by shape errors of the components. [Solution] The gear device 10 according to the embodiment is a gear device including a gear, and has a first member 1 and a second member 2 arranged in a predetermined positional relationship with respect to each other, and the first member 1 has a marking M1 indicating information about the unique shape of the first member 1.

Description

Technical Field

[0001] The present invention relates to a gear device and a method for manufacturing the gear device.

Background Art

[0002] A speed reduction device that reduces and outputs input rotation is known. The applicant has disclosed an eccentric swing type speed reduction device in Patent Document 1. This device is an eccentric swing type speed reduction device including an eccentric body, an external gear that is swung by the eccentric body, an internal gear that meshes with the external gear, an eccentric bearing disposed between the eccentric body and the external gear, and a pin body that synchronizes with the rotation component of the external gear. The components of this device have shapes that are related to each other.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A speed reduction device is composed of a plurality of members. For example, the speed reduction device described in Patent Document 1 is composed of a plurality of members such as an eccentric body, an internal gear, an external gear, an eccentric bearing, and a pin body that are related to each other. Practically, each member has a shape error, and the composite error of a composite portion formed by combining a plurality of members having errors varies depending on the combination of the shape errors of each member.

[0005] For example, torque fluctuations in a reduction gear increase with the amount of misalignment of multiple components. Misalignment is a type of combined error when multiple components are combined; it is small when components with small shape errors are combined, but the variation increases when components with large shape errors are combined. For this reason, it is conceivable to reduce torque fluctuations by understanding the shape errors of each component and avoiding the combination of components with large shape errors during manufacturing. However, this presents the problem of making the manufacturing process more complex.

[0006] From these points, Patent Document 1 does not provide sufficient disclosure from the standpoint of reducing performance variations caused by shape errors of the components.

[0007] This invention has been made in view of these problems, and one of its objectives is to provide a gear device that can reduce performance variations caused by shape errors of the components. [Means for solving the problem]

[0008] To solve the above problems, a gear device according to one aspect of the present invention is a gear device including a gear, comprising a first member and a second member arranged in a predetermined positional relationship with respect to each other. The first member has markings indicating information relating to a shape error specific to the first member.

[0009] Another aspect of the present invention is a method for manufacturing a gear device. This manufacturing method is a method for manufacturing the gear device described above, and includes the step of reading information regarding the unique shape indicated in the marking.

[0010] Furthermore, any combination of the above components, or in which the components or expressions of the present invention are mutually substituted among methods, systems, etc., are also valid embodiments of the present invention. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a gear device that can reduce performance variations caused by shape errors of the components. [Brief explanation of the drawing]

[0012] [Figure 1] This is a cross-sectional view showing a gear device according to an embodiment. [Figure 2] This figure shows an example of a control unit for shape error in a gear mechanism. [Figure 3] This figure shows an example of markings for the internal pin hole and internal pin of an external gear. [Figure 4] This figure shows the variation in the gap between the inner pin hole and the inner pin in Figure 3. [Modes for carrying out the invention]

[0013] The present invention will be described below with reference to the drawings, based on preferred embodiments. In embodiments and modifications, the same or equivalent components and members will be denoted by the same reference numerals, and redundant explanations will be omitted as appropriate. In addition, the dimensions of the members in each drawing will be enlarged or reduced as appropriate for ease of understanding. Furthermore, some members that are not important for explaining the embodiments will be omitted from the drawings.

[0014] Furthermore, while terms including ordinal numbers such as "first" and "second" are used to describe various components, these terms are used solely to distinguish one component from others, and do not limit the components themselves.

[0015] First, the inventor will explain the circumstances that led to this invention. A reduction gear is composed of multiple components, including an eccentric body, an internal gear, an external gear, an eccentric bearing, and a pin body, which are all related to each other. The error from the reference value of the dimensions of a composite part (hereinafter referred to as the "composite dimension") formed by combining multiple components with errors (hereinafter referred to as the "composite error") varies depending on the combination of shape errors of each component. In order to reduce variations in the performance of the gear device, it is desirable to reduce the variation in the composite error when multiple components are combined.

[0016] The composite error caused by combining multiple members is small when combining members with small shape errors, but the variation becomes large when combining members with large shape errors. Therefore, it is conceivable to grasp the shape error of each member and avoid combining members with large shape errors. However, in this case, the manufacturing process of the gear device becomes complicated, leading to an increase in man-hours.

[0017] Therefore, it was devised to provide markings indicating information regarding the shape error specific to each of the plurality of members to be combined. The shape error specific to a member includes dimensional errors caused by processing, positional tolerances, etc., and is the shape error that each member individually has. By reading the shape error indicated by the markings, it becomes possible to easily avoid combinations that result in a large composite error.

[0018] Furthermore, the inventor has devised a method of reducing the composite error by canceling the shape error using the directionality of the shape errors of a plurality of members when the shape error has directionality. It has been found that even when combining members with large shape errors, there are directions in which the shape errors are added and directions in which they are subtracted. That is, when combined in a direction where the shape errors are added to each other, the composite error becomes large, and when combined in a direction where the shape errors are subtracted from each other, the composite error becomes small. For example, the directionality of the shape error can be indicated by the position and angle of the markings. Hereinafter, it will be described using embodiments.

[0019] [Embodiment] The gear device 10 according to the embodiment will be described with reference to the drawings. First, the overall configuration of the gear device 10 will be described with reference to FIGS. 1 and 2, and the variation reduction configuration for reducing performance variation, which is a characteristic configuration of the embodiment, will be described later. FIG. 1 is a cross-sectional view showing the gear device 10 according to the embodiment. FIG. 2 is a diagram showing an example of a management unit that manages the shape error of the gear device 10.

[0020] The gear device 10 mainly includes a shaft member 20, external gears 14, 15 and an internal gear 16 that mesh with each other, a carrier 35, casings 61, 62, 63, a main bearing 26, shaft member bearings 37, 38, an output member 40, rolling elements 47, and a seal member S1. Hereinafter, for convenience of explanation, the direction along the central axis line La of the internal gear 16 is referred to as the "axial direction", and the circumferential direction and the radial direction of a circle centered on the central axis line La are referred to as the "circumferential direction" and the "radial direction", respectively. Also, hereinafter, for convenience, one side in the axial direction (the right side in the figure) is referred to as the "input side", and the other side (the left side in the figure) is referred to as the "anti-input side".

[0021] The shaft member bearings 37, 38 include a first shaft member bearing 37 disposed on the anti-input side of the external gears 14, 15 and a second shaft member bearing 38 disposed on the input side of the external gears 14, 15. The shaft member bearings 37, 38 in this example are deep groove ball bearings, but are not limited thereto.

[0022] The gear device 10 includes the external gears 14, 15 and the internal gear 16, and functions as an eccentric swing type speed reducer that decelerates the rotation input to the shaft member 20 from a drive source (not shown) such as an engine or a motor and outputs it from the output member 40. In this sense, the shaft member 20 may be referred to as an input shaft. The casings 61, 62, 63 function as an outer shell that houses the components of the gear device 10.

[0023] The casings 61, 62, 63 include a first casing 62 provided with the internal gear 16 on its inner circumference, an anti-input side casing 61 disposed on the anti-input side of the first casing 62, and an input side casing 63 disposed on the input side of the first casing 62. The first casing 62 and the anti-input side casing 61 have a hollow cylindrical shape. The anti-input side casing 61 and the first casing 62 are integrated by bolts B2. The input side casing 63 and the first casing 62 are integrated by bolts B1.

[0024] The shaft member 20 comprises a shaft body 21 and two eccentric portions 24 and 25 that are eccentric with respect to the rotation center of the shaft body 21. The rolling elements 47 are cylindrical rollers arranged in a plurality in the circumferential direction between the central holes 45 and 46 of the external gears 14 and 15 and the eccentric portions 24 and 25. The external gears 14 and 15 are provided corresponding to the two eccentric portions 24 via the rolling elements 47 and each has eight internal pin holes 41 and 42 arranged at equal intervals in the circumferential direction. An internal pin 48 is inserted through each internal pin hole 41 and 42. The external gears 14 and 15 are configured to swing as the external teeth formed on the outer circumference of the external gears 14 and 15 move while in contact with the internal gear 16.

[0025] The inner pin 48 includes a cylindrical pin body 50 and an annular inner roller 51 that is rotatably externally fitted to the pin body 50. A configuration without an inner roller is also possible.

[0026] In the following explanation, the outer diameter of the inner pin refers to the outer diameter of the pin body in configurations without an inner roller, and to the outer diameter of the inner roller in configurations with an inner roller.

[0027] The internal gear 16 has an internal gear body 18 integrated with the inner circumference of the first casing 62, and internal teeth 17 formed on the internal gear body 18 that mesh with the external teeth of the external gears 14 and 15. The number of internal teeth 17 is slightly greater than the number of external teeth of the external gears 14 and 15 (only one in this example). The internal teeth 17 may also be external pins that are rotatably supported in pin grooves 19 formed in the internal gear body 18 so as to extend axially.

[0028] The carrier 35 is positioned on the non-input side of the external gears 14 and 15. The carrier 35 is synchronized with the rotational component of the external gears 14 and 15 when the external gears 14 and 15 oscillate, by an internal pin 48 that passes through the external gears 14 and 15.

[0029] The main bearing 26 is positioned on the side of the external gear 14 that is not the input side, between the non-input side casing 61 and the carrier 35. In this example, the main bearing 26 is a cross roller bearing, but is not limited to this. The carrier 35 is rotatably supported by the non-input side casing 61 and the carrier 35 via the main bearing 26. The output member 40 has an annular shape that externally fits onto a projection 36 that protrudes from the carrier 35 toward the non-input side, and is fixed to the carrier 35 by bolts B3 and integrated with it. The sealing member S1 is interposed between the output member 40 and the non-input side casing 61 and functions as an oil seal that seals the space between the main bearing 26 and the external space of the gear unit 10.

[0030] The operation of the gear mechanism 10 will now be explained. When the shaft member 20 rotates due to the rotation transmitted from the drive source, the external gears 14 and 15 oscillate due to the eccentric portions 24 and 25 of the shaft member 20. As the external gears 14 and 15 oscillate, the meshing position between the external gears 14 and 15 and the internal gear 16 changes sequentially in the circumferential direction. As a result, with each rotation of the shaft member 20, either the external gears 14 and 15 or the internal gear 16 rotates by the difference in the number of teeth between them. In this embodiment, the external gears 14 and 15 rotate. This rotational component is transmitted to the carrier 35 via the internal pin 48, and output from the carrier 35 to the driven member (not shown) via the output member 40 as output rotation.

[0031] (Variation reduction configuration) Referring to Figures 2-4, a configuration that reduces performance variation, which is a characteristic configuration of the embodiment, will be described. Figure 2 shows control units 3A, 3D, 3E, and 3F as an example of a control unit for managing shape errors in the gear device 10. In the gear device 10, control units 3A, 3D, 3E, and 3F each have a first member 1 and a second member 2 arranged in a predetermined positional relationship with each other, and the first member 1 has a marking M1 that indicates information regarding shape errors specific to the first member 1.

[0032] The control unit refers to the part that controls the combined shape errors of the first member 1 and the second member 2 in order to reduce the combined error of an assembly made up of multiple members. The predetermined positional relationship refers to the design positional relationship between the first member 1 and the second member 2. The combined error referred to here may include not only the shape errors of the first member 1 and the second member 2, but also the shape errors of other members and errors that occur during assembly.

[0033] Shape errors inherent to a component include dimensional errors such as inner and outer diameters, positional errors such as misalignment, angular errors, and, in the case of gears, errors in gear precision, etc., that occur during the manufacturing process of the component. These are shape errors that each component possesses individually, and information regarding shape errors is information that can identify the shape errors. Note that error refers to the error relative to a reference value, and the reference value may be a design value, a target value, or a theoretical value. In this specification, unless otherwise specified, the term error means the error relative to the design value. Misalignment refers to the error in the position coordinates of the center of the inner or outer diameter.

[0034] There are no limitations on the type of marking M1; for example, display elements such as letters, numbers, symbols, figures, pictures, colors, patterns, and combinations thereof can be used. There are no limitations on the form of the marking M1; for example, it may be convex, concave, or flat relative to the placement surface, or it may be made by applying non-metallic materials such as ink or metallic materials, or formed by engraving or sandblasting. The marking M1 may be visible to the naked eye or electronically readable.

[0035] One-dimensional, two-dimensional, and other types of barcodes can be used as electronically readable markings (M1). This is advantageous because they are electronically readable and facilitate automation.

[0036] The marking M1 is provided on both the first member 1 and the second member 2, which allows for the avoidance of combining members with large shape errors and enables assembly in a way that cancels out shape errors. This reduces combined errors and minimizes performance variations.

[0037] The following description explains an example in which a marking M1 is provided on the first member 1 and a marking M2 is provided on the second member 2. In this case, the information shown in markings M1 and M2 can be used to further reduce composite errors and performance variations. The description given for marking M1 applies to marking M2 as well. In this example, markings M1 and M2 are two-dimensional barcodes and are configured to read information including errors in the inner or outer diameter, errors in the center position of the inner or outer diameter (hereinafter referred to as "off-center"), and the direction of deviation of the center position of the inner or outer diameter (hereinafter referred to as "off-center direction").

[0038] The control unit 3A will now be explained. The following explanation will mainly describe an example using an external gear 15, but this explanation can also be applied to an external gear 14. Figure 3 shows the markings M1 and M2 of the internal pin hole 42 and internal pin 48 of the external gear 15. The internal pin 48 and internal pin hole 42 are each arranged at predetermined intervals in the circumferential direction, at 45° intervals in this example. As mentioned above, the gear device 10 has an external gear 15 having an internal pin hole 42, and an internal pin 48 that penetrates the internal pin hole 42 in the axial direction and transmits the rotational component of the external gear 15 to a predetermined member. In the control unit 3A, the first member 1 is one of the external gear 15 and the internal pin 48, and the second member 2 is the other of the external gear 15 and the internal pin 48.

[0039] In the example shown in Figure 3, the external gear 15 is designated as the first member 1 and marked with marking M1, while the internal pin 48 is designated as the second member 2 and marked with marking M2.

[0040] As a combined dimension, the gap between the inner diameter d42 of the inner pin hole 42 and the outer diameter d48 of the inner pin 48 (hereinafter referred to as "pin hole gap c1") is shown by Equation 1. Note that the symbol h25 is the eccentricity of the eccentric portion 25, and the symbol c2 is the inner pin gap between the inner diameter of the inner roller 51 and the outer diameter of the pin body 50. Note that if the configuration does not have an inner roller 51, the gap c2 is 0. Pin hole gap c1=(d42-d48+c2-2·h25) / 2···(1) From Equation 1, the error of the pinhole gap c1 as a composite error is given as the combined value of the errors of the inner diameter d42, outer diameter d48, gap c2, and eccentricity h25.

[0041] If the pinhole gap c1 is excessively small compared to the design value, contact resistance increases, leading to increased torque loss and torque fluctuations. Conversely, if this gap is excessively large compared to the design value, rotational accuracy decreases. Therefore, it is important to combine the external gear 15 and internal pin 48 during the manufacturing process to minimize errors in these gaps.

[0042] Therefore, in this embodiment, a marking M1 is provided on the external gear 15 and a marking M2 is provided on the internal pin 48. The marking M1 is configured to acquire at least one of the inner diameter d42 of the internal pin hole 42 and the positional displacement (position coordinates) of the internal pin hole 42. The marking M2 is configured to acquire at least one of the outer diameter d48 of the internal pin 48 and the positional displacement (position coordinates) of the internal pin 48. The marking M1 may also be configured to acquire at least one of the inner diameter d42 of all internal pin holes 42 and the positional displacement (position coordinates) of all internal pin holes 42.

[0043] Furthermore, for a management unit separate from management unit 3A, marking M1 may be configured to acquire at least one of the following: the outer diameter of the external teeth 152 of the external gear 15, the inner diameter of the central hole 46, the gear precision of the external teeth 152, and the tooth groove runout performance of the external teeth 152.

[0044] The runout performance of a gear includes at least one of the following: the amount of deviation of the gear axis's tooth groove relative to the runout axis (hereinafter referred to as "tooth groove runout amount") and the rotational position where the maximum or minimum runout value appears (hereinafter referred to as "tooth groove runout direction"). In this embodiment, the tooth groove runout direction of the external gear 14 and the tooth groove runout direction of the external gear 15 are combined so that they are substantially the same.

[0045] Furthermore, in the example shown in Figure 3, a marking M3 is provided on the internal gear 16. The marking M3 is configured to obtain at least one of the following: the inner diameter of the internal teeth 162 of the internal gear 16, the gear precision of the internal teeth 162, and the runout of the tooth grooves of the internal teeth. Markings on such parts may indicate predetermined information through their color tone, brightness, size, position, etc.

[0046] In Management Department A, an example of how to use the information indicated by the markings is explained. When manufacturing the gear unit 10, before assembly, a reading device (not shown) such as a barcode reader is used to acquire the marking M1 on the external gear 15, which is the first component 1, and the marking M2 on the internal pin 48, which is the second component 2. Based on the acquisition results, a combination of the external gear 15 and the internal pin 48 is selected. For example, if the shape error of the first component 1 is large, a second component 2 with a small shape error is selected from among several second components 2 and combined with it. Similarly, if the shape error of the second component 2 is large, a first component 1 with a small shape error is selected from among several first components 1 and combined with it. If the misalignment of the first component 1 is large, a second component 2 that cancels out the misalignment of the first component 1 is selected and combined with it. Similarly, if the misalignment of the second component 2 is large, a second component 1 that cancels out the misalignment of the second component 2 is selected from among several first components 1 and combined with it. This method of use can be applied similarly to other management departments.

[0047] Figure 4 shows the variation in the gap between the inner pin hole 41 and the inner pin 48, with the horizontal axis showing the position of the inner pin 48 and the vertical axis showing the pin hole gap c1. Figure 4(A) shows the variation A of the pin hole gap c1 for each of the eight inner pin positions when using the information indicated by the markings (hereinafter referred to as "marking information") and avoiding combinations of members with large shape errors. Here, the position at 12 o'clock in the figure is designated as P1, and the positions are designated P2 to P8 clockwise from P1. For comparison, Figure 4(B) shows the variation B of the pin hole gap c1 for each of the eight inner pin positions when the members are combined without using the marking information.

[0048] As shown in Figure 4(B), in the case of combinations that do not utilize marking information, there are cases where the gap c1 exceeds 0.005 mm, and the variation B of the gap c1 is large. In contrast, when marking information is used, as shown in Figure 4(A), there are no cases where the gap c1 exceeds 0.005 mm, and the variation A of the gap c1 is smaller than the variation B. Thus, by utilizing marking information, the variation in the gap c1 can be reduced. Large variations in the gap c1 lead to large torque fluctuations, but reducing the variation in the gap c1 can suppress torque fluctuations.

[0049] The control unit 3D will now be described. As shown in Figure 2, the gear device 10 has a first casing 62 on which an internal gear 16 is provided on its inner circumference, and an input-side casing 63 that fits into the first casing 62. The input-side casing 63 has a shape that covers one axial side of the first casing 62. In the control unit 3D, the first member is one of the first casing 62 and the input-side casing 63, and the second member is the other of the first casing 62 and the input-side casing 63.

[0050] For example, the first casing 62 may be marked with a marking M1 (not shown) as the first member, and the input-side casing 63 may be marked with a marking M2 (not shown) as the second member. Marking M1 indicates information regarding the outer diameter of the outer circumference of the fitting portion 624 of the first casing 62, and shape errors such as misalignment. Marking M2 indicates information regarding the inner diameter of the inner circumference of the fitting hole 634 of the input-side casing 63, and shape errors such as misalignment. By combining the information shown in markings M1 and M2 in the control unit 3D, the variation in the misalignment of the input-side casing 63 relative to the first casing 62 can be reduced.

[0051] The control unit 3E will now be described. As shown in Figure 2, the gear device 10 has a first casing 62 on which an internal gear 16 is provided on its inner circumference, and a non-input side casing 61 which is connected to the first casing 62 and rotatably supports the carrier 35 via a main bearing. In the control unit 3E, the first member is one of the first casing 62 and the non-input side casing 61, and the second member is the other of the first casing 62 and the non-input side casing 61.

[0052] For example, the first casing 62 may be designated as the first member and marked with marking M1 (not shown), and the non-input side casing 61 may be designated as the second member and marked with marking M2 (not shown). Marking M1 indicates information regarding the shape errors such as the inner diameter and misalignment of the internal teeth 162 of the internal gear 16 of the first casing 62. Marking M2 indicates information regarding the shape errors such as the inner diameter and misalignment of the bearing hole 612 of the non-input side casing 61. By combining the control unit 3E using the information shown in markings M1 and M2, the variation in the misalignment of the bearing hole 612 of the non-input side casing 61 relative to the internal teeth 162 of the internal gear 16 of the first casing 62 can be reduced.

[0053] The control unit 3F will now be explained. As shown in Figure 2, the gear device 10 has a first casing 62 on which an internal gear 16 is provided on its inner circumference, and an external gear 15 that meshes with the internal gear 16. In the control unit 3F, the first member is one of the first casing 62 and the external gear 15, and the second member is the other of the first casing 62 and the external gear 15.

[0054] For example, the first casing 62 may be marked with marking M1 (not shown) as the first member, and the external gear 15 may be marked with marking M2 (not shown) as the second member. Marking M1 indicates information regarding shape errors such as the inner diameter, misalignment, and gear accuracy of the internal gear 16. Marking M2 indicates information regarding shape errors such as the outer diameter, misalignment, and gear accuracy of the external gear 15. By combining the control unit 3F using the information shown in markings M1 and M2, the variation in misalignment and meshing accuracy of the external gear 15 relative to the internal gear 16 can be reduced.

[0055] The above explanation described a variation reduction configuration that focuses on the magnitude of shape errors. However, when shape errors have directionality, such as the direction of misalignment, the combined error can be reduced by using the directionality of the shape errors of multiple components to cancel out the shape errors. Even when combining components with significant shape errors, it has been found that there are directions in which these shape errors are added and directions in which they are subtracted. In other words, combining components in a direction in which their shape errors are added together results in a large combined error, while combining components in a direction in which their shape errors are subtracted together results in a small combined error. The directionality of shape errors can be indicated by the position or angle of markings.

[0056] In the example in Figure 3, marking M1 is positioned in the direction that maximizes the runout of the external gear 14, and marking M2 is positioned in the direction that maximizes the runout of the internal pin 48. In the example in Figure 3(A), markings M1 and M2 are positioned in the same direction, so the runouts of each component are in phase. In the example in Figure 3(B), markings M1 and M2 are positioned in opposite directions, so the runouts of each component are in opposite phase. If in phase is preferable for the variation configuration, they may be combined so that they are approximately in phase, and if opposite phase is preferable for the variation configuration, they may be combined so that they are approximately in opposite phase.

[0057] The features of the gear device 10 configured as described above will now be explained. The gear device 10 of the embodiment is a gear device including gears, and has a first member 1 and a second member 2 arranged in a predetermined positional relationship with respect to each other. The first member 1 has a marking M1 that indicates information regarding a shape error specific to the first member 1.

[0058] This configuration allows for obtaining information about shape errors from marking M1. By utilizing the obtained information about shape errors, it is possible to avoid combining components with large shape errors. As a result, combined errors can be reduced, and performance variations can be minimized.

[0059] As an example, the marking M1 may be provided on any of the following: the shaft member 20, the external gears 14 and 15, the internal gear 16, the carrier 35, the casings 61, 62, and 63, the main bearing 26, the shaft member bearings 37 and 38, the output member 40, and the rolling element 47. In this case, information regarding the shape errors of these components can be obtained from the marking M1. Furthermore, this information can be used to reduce combined errors and minimize performance variations.

[0060] The above is a description of the embodiment.

[0061] The present invention has been described above based on the embodiments. These embodiments are illustrative, and it will be understood by those skilled in the art that various modifications and changes are possible within the scope of the claims of the present invention, and that such modifications and changes are also within the scope of the claims of the present invention. Accordingly, the descriptions and drawings herein should be treated as illustrative rather than limiting.

[0062] (modified version) The following describes modified examples. In the drawings and descriptions of the modified examples, components and parts that are the same as or equivalent to those in the embodiments are denoted by the same reference numerals. Descriptions that overlap with those in the embodiments will be omitted as appropriate, and the descriptions will focus on the configurations that differ from those in the embodiments.

[0063] The above description shows an example of managing control units 3A, 3D, 3E, and 3F, but the present invention is not limited to this. Control units may be provided in locations other than these.

[0064] The above description shows examples of marking information on one or two components, but the present invention is not limited thereto. It may also be configured to reduce combined errors by utilizing information marking on three or more components.

[0065] The above description shows an example of directly reading and obtaining information about shape errors from markings such as markings M1 and M2, but the present invention is not limited to this. For example, code information may be obtained from the markings, and using that code information as a key, information about shape errors may be obtained from a data server (not shown) that stores information about shape errors corresponding to that code information.

[0066] In the above description, an example was shown in which the gear device 10 is a so-called center-crank type eccentric oscillating reducer in which the crankshaft is positioned at the axis of the internal gear, but the present invention is not limited to this. The gear device can be of any type as long as it has gears and multiple members that are arranged in a predetermined positional relationship with each other. For example, the gear device may be an eccentric oscillating reducer, a simple planetary reducer, or a flexible meshing reducer. In the case of an eccentric oscillating reducer, the specific type is not particularly limited, and for example, it may be a so-called distribution type eccentric oscillating reducer in which multiple crankshafts are positioned at an offset position from the axis of the internal gear. In the case of a flexible meshing reducer, the specific type is not particularly limited. The types of flexible meshing reducers may be, for example, a cylindrical type with two internal gears, a cup type with one internal gear, or a top hat type.

[0067] The above description shows an example in which the gear unit 10 has two external gears 14, but the present invention is not limited to this. The gear unit may have one or three or more external gears.

[0068] Each of these modifications produces the same functions and effects as the embodiments.

[0069] Any combination of the embodiments and modifications described above is also useful as an embodiment of the present invention. The new embodiments resulting from these combinations possess the combined effects of both the respective embodiments and modifications. [Explanation of Symbols]

[0070] 1 First member, 2 Second member, 10 Gear mechanism, 14, 15 External gears, 16 Internal gear, 20 Shaft member, 24, 25 Eccentric part, 26 Main bearing, 35 Carrier, 37, 38 Shaft member bearing, 40 Output member, 41, 42 Internal pin holes, 45, 46 Center hole, 47 Rolling element, 48 Internal pin, 61, 62, 63 Casing.

Claims

1. A gear system including gears, It has a first member and a second member that are arranged in a predetermined positional relationship with respect to each other, The gear device having a marking indicating information regarding a shape error specific to the first member.

2. The second member has markings indicating information regarding shape errors specific to the second member. The gear apparatus according to claim 1.

3. An external gear having an internal pin hole, and an internal pin that penetrates the internal pin hole axially and transmits the rotational component of the external gear to a predetermined member, The first member is one of the internal pin and the external gear, and the second member is the other of the internal pin and the external gear. The gear apparatus according to claim 1.

4. The marking indicates at least one of the following: information regarding the outer diameter of the inner pin and information regarding the misalignment of the inner pin. The gear apparatus according to claim 3.

5. The marking indicates at least one of the following: information relating to the inner diameter of the inner pin hole and information relating to the misalignment of the inner pin hole. The gear apparatus according to claim 3.

6. A casing, and a carrier rotatably supported by the casing via bearings, The carrier has a shaft member that is rotatably supported via another bearing, The first member is one of the casing and the shaft member, and the second member is the other of the casing and the shaft member. The gear apparatus according to claim 1.

7. It comprises a casing and a shaft member rotatably supported by the casing via a bearing, The first member is one of the casing and the shaft member, and the second member is the other of the casing and the shaft member. The gear apparatus according to claim 1.

8. It comprises a casing on which an internal gear is provided on the inner circumference, and another casing that fits into the said casing, The other casing has a shape that covers one side of the casing in the axial direction, The first member is the casing and the other casing, and the second member is the casing and the other casing. The gear apparatus according to claim 1.

9. It comprises a casing on which an internal gear is provided on the inner circumference, and another casing connected to the aforementioned casing and rotatably supporting the carrier via a main bearing, The first member is one of the casing and the other casing, and the second member is the other of the casing and the other casing. The gear apparatus according to claim 1.

10. It has a casing with an internal gear on its inner circumference, and an external gear that meshes with the internal gear, The first member is one of the casing and the external gear, and the second member is the other of the casing and the external gear. The gear apparatus according to claim 1.

11. A method for manufacturing a gear device according to claim 1, The process includes reading information regarding the inherent shape error indicated by the marking, A method for manufacturing a gear system.

Images