JP7737281B2 - Derailleur with anti-detachment function - Google Patents

Description

The present invention relates to a transmission with a disengagement prevention function.

Lock-prevention devices that hold the transmission (reduction gear) attached to an industrial robot so that it does not fall off the robot are known. For example, the lock-prevention device described in Patent Document 1 prevents the transmission from falling off by providing a protrusion on the hold flange of the transmission case and a recess in the plate on the robot side.

Japanese Patent Application Laid-Open No. 2004-138094

However, with the configuration described in Patent Document 1, if the recessed portion of the plate on the robot (the counterpart member) or the transmission case is damaged, there is a risk that the transmission may fall off the robot, and reliable countermeasures are necessary for robots that work closely with humans.

The present invention aims to provide a transmission with a disengagement prevention function that can prevent the transmission from disengaging from the mating member.

One aspect of the present invention relates to a transmission with a disengagement prevention function. The transmission is attached to a mating member and changes the speed of the rotation of a drive source that generates rotational force before outputting it. The connecting member connects the transmission to the mating member. The connecting member maintains the connection between the transmission and the mating member regardless of changes in the position of the transmission relative to the mating member.

According to the above configuration, even if a malfunction occurs in the reducer and the position of the reducer relative to the mating member changes (shifts), the connecting member can maintain the connection between the reducer and the mating member, thereby preventing the transmission from falling off the mating member.
Furthermore, unlike the conventional technology described above, there is no need to provide a special design for preventing the transmission from falling off, such as by providing a protrusion on the hold flange of the transmission. In other words, the transmission and the mating member can be connected using a connecting member without any additional processing on the transmission itself. This ensures freedom in the design of the transmission, and increases the versatility of the transmission with a fall prevention function.

In the above configuration, the connecting member may be string-shaped.

The above configuration may include a case fixed to the mating member, and the connecting member may connect the case and the mating member.

In the above configuration, the flange portion of the case may have a through hole that passes through in the axial direction, and a fixing member that is inserted or screwed into the through hole, and the connecting member may be attached to the fixing member.

In the above configuration, the connecting member may have a first connecting member fixed to the case by the fixing member.

In the above configuration, the connecting member may have a second connecting member fixed to the outer peripheral surface of the case by the fixing member.

In the above configuration, the connecting member may have a third connecting member that is wrapped around and fixed to the through hole.

In the above configuration, the case may have a groove formed to connect to the through hole of the flange portion and in which the third connecting member is embedded.

In the above configuration, the drive unit may have a hollow shaft extending in the axial direction and into which rotation from the drive source is input, and the connecting member may have a fourth connecting member passing through the hollow shaft.

In the above configuration, multiple transmissions may be provided on the mating member and connected by the connecting member.

In the above configuration, the transmission may be an eccentric oscillating reducer that includes a case fixed to the mating member, at least one crankshaft located within the case and rotating in response to the rotation of the drive source, and an output shaft located within the case that reduces the rotation of the drive source and outputs it, and that reduces the rotation of the crankshaft and transmits it to the output shaft, causing the output shaft to rotate at a reduced speed relative to the rotation of the drive source.

A transmission with a disengagement prevention function according to another aspect of the present invention comprises a transmission that changes the speed of rotation of a drive source that generates rotational force and outputs the rotation; and a connecting member that connects the transmission to a mating member using the transmission. The transmission comprises a case fixed to the mating member, at least one crankshaft located within the case that rotates in response to the rotation of the drive source, and an output shaft located within the case that decelerates and outputs the rotation of the drive source. The transmission is an eccentric oscillating reducer that decelerates the rotation of the crankshaft and transmits it to the output shaft, causing the output shaft to rotate at a reduced speed relative to the rotation of the drive source.

According to the above configuration, it is possible to prevent the transmission from falling off the mating member.
Furthermore, unlike the conventional technology described above, there is no need to provide a special design for preventing the transmission from falling off, such as by providing a protrusion on the hold flange of the transmission. In other words, the transmission and the mating member can be connected using a connecting member without any additional processing on the transmission itself. This ensures freedom in the design of the transmission, and increases the versatility of the transmission with a fall prevention function.

This invention provides a transmission with a disengagement prevention function that can prevent the transmission from disengaging from the mating member.

1 is a perspective view showing an example of a transmission with a disengagement prevention function according to a first embodiment. FIG. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1 is a cross-sectional view of a transmission with a disengagement prevention function according to a first embodiment. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. FIG. 10 is a perspective view showing an example of a transmission with a disengagement prevention function according to a second embodiment. FIG. 10 is a cross-sectional perspective view of a transmission with a disengagement prevention function according to a second embodiment. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. FIG. 11 is a schematic diagram of a robot using a transmission with a disengagement prevention function in a third embodiment.

A transmission with a disengagement prevention function according to an embodiment of the present invention will be described in detail below with reference to the drawings. In the embodiments described below, corresponding components may be assigned the same reference numerals and their description may be omitted. In the following description, expressions indicating relative or absolute arrangements, such as "parallel," "orthogonal," "center," and "coaxial," not only refer to such arrangements in a strict sense, but also to a state in which there is a relative displacement with a tolerance or an angle or distance that provides the same function.

(First embodiment)
Fig. 1 is a perspective view of a reducer 100 with a fall-off prevention function according to the first embodiment. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. The robot R is not shown in Fig. 1, but is shown in Fig. 2.
As shown in Figures 1 and 2, the reducer 100 with anti-detachment function according to this embodiment comprises a reducer 1 that reduces the rotation of a drive source that generates a rotational force and outputs the reduced rotation, and a connecting member 50 that connects the reducer 1 to a robot R (Figure 2) that uses the reducer 1.

[Robot (mate component)]
The robot R is preferably an industrial robot, and more preferably a cooperative (collaborative) robot. A cooperative (collaborative) robot is a robot that cooperates with workers in fields such as factory automation (FA).
Furthermore, the robot R may be an articulated robot having multiple transmissions.

[Reduction gear]
The reducer 1 is provided at a connecting portion of a pair of rotatably connected arms (a joint portion of the robot R). The reducer 1 reduces and outputs motor torque input from a motor (not shown) serving as a drive source.
The reducer 1 need not be limited to the configuration described below, but may be any other device capable of changing the speed of the rotation of a drive source that generates a rotational force. For example, instead of the reducer 1, a speed increaser that increases the speed of the rotation of a drive source that generates a rotational force and outputs the increased speed may be used.

The reducer 1 is a so-called solid transmission in which the input shaft 8 (described later) is solid. The reducer 1 includes a case 30 and a reduction mechanism 40. The case 30 includes a main body 32 and a flange 34. The flange 34 has a shape that protrudes radially outward from the main body 32. In the description of the first embodiment, the direction along the axis O1 of the main body 32 is simply referred to as the axial direction, the direction intersecting the axis O1 when viewed from the axial direction is referred to as the radial direction, and the direction rotating around the axis O1 is referred to as the circumferential direction. The side of the reducer 1 to which the drive source is connected is referred to as the input side, and the side to which a mechanical unit such as an arm that receives the output of the reducer 1 is connected is referred to as the output side. The drive source is an example of a first member, and the mechanical unit such as an arm is an example of a second member. The reducer 1 converts the rotational speed between the first and second members at a predetermined rotational speed ratio to transmit driving force.

The main body 32 is formed in a cylindrical shape along the axis O1. The main body 32, which is an example of a first cylindrical portion, is open on its input side in the direction of the axis O1 . The reduction mechanism 40 is rotatably housed in the opening of the main body 32. A flange 34 is integrally formed on the output side of the main body 32. A plurality of (e.g., three) transmission gears 40A and an input gear 40B are exposed on the input side of the reducer 1.

The flange 34 is provided on the outer periphery of the case 30 and has through holes 105 that penetrate in the axial direction. The through holes 105 include first through holes 105A spaced at regular intervals in the circumferential direction and second through holes 105B that are provided between adjacent first through holes 105A in the circumferential direction. The first through holes 105A are fastening holes through which fastening members (not shown) such as bolts that fasten the reducer 1 to the robot R pass. The second through holes 105B have female threads (not shown) formed into them, into which fixing members 106 (described below) are screwed.

A groove 107 that continues to the second through-hole 105B is formed on the surface 34A of the flange 34 that overlaps with the robot R. The groove 107 is formed radially outward from the output end of the second through-hole 105B and along the radial direction.

Flange 34 also has an outer peripheral surface 108 formed on the outer periphery of flange 34. A female thread (not shown) is formed in the circumferential center of outer peripheral surface 108. A fixing member 106 (described below) is screwed into this female thread.

[Fixing member]
The fixing member 106 is screwed into the female thread portion of the outer circumferential surface 108 and also into the second through-hole 105B of the flange portion 34 .
The fixing member 106 has a head 106A that protrudes toward the input side and a shaft 106B (FIG. 6) that has a smaller diameter than the head 106A. The shaft 106B of the fixing member 106 is threaded into the second through-hole 105B of the flange 34. The connecting member 50 is fixed by using the fixing member 106 that is threaded into the second through-hole 105B (details will be described later).

FIG. 3 is a cross-sectional view showing the configuration of the reducer 100 with a fall-off prevention function according to the embodiment, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.
The reducer 1 is configured to rotate the crankshaft 10A by rotating the input shaft 8 corresponding to the input gear 40B, and to obtain an output rotation that is reduced from the input rotation by oscillating and rotating the oscillating gears 14 and 16 in conjunction with the eccentric portions 10a and 10b of the crankshaft 10A.

As shown in Figures 3 and 4, the reducer 1 includes an outer cylinder 2 corresponding to the main body 32 (first cylindrical portion), a carrier portion 4 (output shaft) which is an example of the second cylindrical portion, an input shaft 8, multiple (e.g., three) crankshafts 10A, a first oscillating gear 14, a second oscillating gear 16, and multiple (e.g., three) transmission gears 20. The transmission gear 20 corresponds to the transmission gear 40A in Figure 1.

The outer cylinder 2 forms the outer surface of the reducer 1 and has a roughly cylindrical shape. Numerous pin grooves 2b are formed on the inner peripheral surface of the outer cylinder 2. Each pin groove 2b is arranged to extend in the axial direction of the outer cylinder 2 and has a semicircular cross-section perpendicular to the axial direction. These pin grooves 2b are arranged at equal intervals around the circumferential direction on the inner peripheral surface of the outer cylinder 2.

The outer cylinder 2 has a large number of internally toothed pins 3. Each internally toothed pin 3 is attached to a pin groove 2b. Specifically, each internally toothed pin 3 is fitted into a corresponding pin groove 2b and is arranged in a position extending in the axial direction of the outer cylinder 2. As a result, the large number of internally toothed pins 3 are lined up at equal intervals along the circumferential direction of the outer cylinder 2. These internally toothed pins 3 mesh with the first external teeth 14a of the first oscillating gear 14 and the second external teeth 16a of the second oscillating gear 16.

The carrier unit 4 is housed within the outer cylinder 2 and is arranged coaxially with the outer cylinder 2. The carrier unit 4 rotates relative to the outer cylinder 2 (case 30) around the same axis. Specifically, the carrier unit 4 is arranged radially inside the outer cylinder 2 and is supported in this state for relative rotation with respect to the outer cylinder 2 by a pair of main bearings 6 spaced apart from each other in the axial direction.

The carrier portion 4 comprises a base portion having a substrate portion 4a and multiple (e.g., three) shaft portions 4c, and an end plate portion 4b.

The input shaft 8 functions as an input section to which the driving force of a drive motor (not shown) is input. The input shaft 8 is inserted into the through-hole 4f of the end plate section 4b and the through-hole 4d of the base section 4a. The input shaft 8 is positioned so that its axis coincides with the axis of the outer tube 2 and the carrier section 4, and rotates around its axis. An input gear 8a is provided on the outer peripheral surface of the tip of the input shaft 8.

The three crankshafts 10A are arranged at equal intervals around the input shaft 8 within the outer cylinder 2 (see Figure 4). Each crankshaft 10A is supported by a pair of crank bearings 12a, 12b to be rotatable about its axis relative to the carrier portion 4 (see Figure 3).

Each crankshaft 10A has a shaft body 12c and eccentric portions 10a and 10b formed integrally with the shaft body 12c.

One end of the crankshaft 10A, i.e., the portion axially outward of the portion that is attached to the mounting hole 4e of the base plate portion 4a, is provided with a mating portion 10c to which the transmission gear 20 is attached. Note that the embodiment of the reducer 1 is not limited to the example shown in Figure 3; the crankshaft 10A may be axially reversed, with the mating portion 10c positioned axially outward of the mounting hole 4g of the end plate portion 4b.

The first oscillating gear 14 is disposed in the closed space within the outer cylinder 2 and is attached to the first eccentric portion 10a of each crankshaft 10A via a first roller bearing 18a. When each crankshaft 10A rotates and the first eccentric portion 10a rotates eccentrically, the first oscillating gear 14 rotates oscillatingly while meshing with the internal tooth pin 3 in conjunction with this eccentric rotation.

The second oscillating gear 16 is disposed in the closed space within the outer cylinder 2 and is attached to the second eccentric portion 10b of each crankshaft 10A via a second roller bearing 18b. The first oscillating gear 14 and the second oscillating gear 16 are arranged side by side in the axial direction to correspond to the arrangement of the first eccentric portion 10a and the second eccentric portion 10b. When each crankshaft 10A rotates and the second eccentric portion 10b rotates eccentrically, the second oscillating gear 16 rotates oscillatingly while meshing with the internal tooth pin 3 in conjunction with this eccentric rotation.

Each transmission gear 20 transmits the rotation of the input gear 8a to the corresponding crankshaft 10A. Each transmission gear 20 is fitted onto a mating portion 10c provided at one end of the shaft body 12c of the corresponding crankshaft 10A. Each transmission gear 20 rotates integrally with the crankshaft 10A around the same axis as the rotational axis of the crankshaft 10A. Each transmission gear 20 has external teeth 20a that mesh with the input gear 8a.

[Connecting member]
1 and 2 , the connecting member 50 that connects the reducer 1 and the robot R connects the case 30 of the reducer 1 and the robot R. The connecting member 50 is a string-like member. The connecting member 50 is preferably made of steel wire, stainless steel wire for rust prevention, or the like.

However, the present invention is not limited to this, and the connecting member 50 may be any string-like member. The term "string-like" includes those that are long in one direction, and/or that can bend and deform, and/or that can elastically deform so as to be curved, and/or that can stretch and contract (flexibly deform) along one direction.
For example, instead of steel wire, stainless steel wire, resin, conductive wire, nylon, polyester, polypropylene, polyethylene, vinylon (Cremona), cotton, hemp, etc., chain, rubber cord, coil spring, etc. may be used. In the case of rubber cord, it is desirable that the elongation rate is 300% or less of the free length. In the case of coil spring, it is desirable that the elongation rate is 150% or less of the free length. This is because, for example, when the reducer 1 is suspended by the connecting member 50, the connecting member 50 (rubber cord or coil spring) will bend and deform with almost no elongation from the free length.

If the reducer 1 is lightweight, the connecting member 50 may be made of a non-metallic material. For example, the connecting member 50 may be made of resin. The length of the connecting member 50 need only be long enough to connect the case 30 and the robot R. The thickness of the connecting member 50 can be set to match the weight of the reducer 1.

The connecting member 50 has a first connecting member 51 fixed to the fixing member 106, a second connecting member 52 fixed to the fixing member 106, and a third connecting member 53 wrapped around and fixed to the second through-hole 105B. The connecting member 50 can be any one or a combination of two or more of the first connecting member 51, second connecting member 52, and third connecting member 53. Furthermore, the connecting member 50 can be provided with multiple pieces of any one type of the first connecting member 51, second connecting member 52, and third connecting member 53.

The first connecting member 51 has a first annular portion 51A that is annular and provided at the end of the first connecting member 51, and a first connecting base portion 51B whose end is fastened and fixed to the first annular portion 51A. The first annular portion 51A is fixed to the flange portion 34 by a fixing member 106. Specifically, with the ring of the first annular portion 51A overlapping the second through-hole 105B, the shaft portion 106B of the fixing member 106 is screwed into the second through-hole 105B from the side opposite the flange portion 34, thereby fixing the first connecting member 51 to the fixing member 106. Note that the first connecting member 51 may also be fixed together with the fixing member 106 that fixes the robot R and the reducer 1 using the first through-hole 105A.

The second connecting member 52 has a second annular portion 52A that is annular and provided at the end of the second connecting member 52, and a second connecting base portion 52B whose end is fastened and fixed to the second annular portion 52A. The second annular portion 52A is fixed to the outer peripheral surface 108 by a fixing member 106. Specifically, the ring of the second annular portion 52A is placed over a fastening hole (not shown) provided in the outer peripheral surface 108, and the second shaft portion of the fixing member 106 is screwed into the fastening hole from the opposite side to the outer peripheral surface 108, thereby fixing the second connecting member 52 to the fixing member 106.

The third connecting member 53 is fixed using the second through hole 105B, into which the fixing member 106 is not threaded. Specifically, the third connecting member 53 has a third connecting base 53A that passes through the second through hole 105B, a connecting portion 53B that extends from the end of the third connecting base 53A radially outward from the flange portion 34, a first folded portion 53C that extends from the connecting portion 53B in a direction along the third connecting base 53A, a second folded portion 53D that extends radially inward from the end of the first folded portion 53C, and a connecting tube 53E that crimps and fixes the end of the third connecting member 53 to the third connecting base 53A. Note that the third connecting member 53 may also be folded to form a loop.

The connecting portion 53B is embedded in the groove 107. The first folded portion 53C is located radially outward from the outer circumferential surface of the flange portion .
The terminal portion of the third connecting member 53 is passed through the second through-hole 105B, and then passed through the connecting pipe 53E together with the third connecting base 53A. The connecting pipe 53E is then crimped and plastically deformed, thereby crimping and fixing the end of the third connecting member 53. In this embodiment, the end of the third connecting member 53 is crimped and fixed to the connecting pipe 53E, but it may also be folded back to form a loop and fixed with a knot or the like.

The other end of the connecting member 50 is fixed to the robot R. The configuration for fixing the other end of the connecting member 50 to the robot R is not particularly limited, but the above-described configuration for connecting one end of the connecting member 50 to the reducer 1 (case 30) may be adopted.

[Action and effect]
The effects of the first embodiment will be described below.
The above-described reducer 100 with a fall-off prevention function includes the reducer 1 and a connecting member 50 that connects the reducer 1 to a robot R ( FIG. 2 ) that uses the reducer 1. Therefore, even if a part of the reducer 1 is damaged, the reducer 1 can be prevented from falling off the robot R. In other words, even if, for example, a part of the reducer 1 is damaged and the position of the reducer 1 relative to the robot R changes (shifts), the connecting member 50 can maintain the connected state between the robot R and the reducer 1. Therefore, the reducer 1 can be prevented from falling off the robot R.

Furthermore, unlike the prior art described above, there is no need to provide a special design to prevent the transmission from falling off, such as by providing a protrusion on the hold flange of the reducer 1. In other words, the reducer 1 and robot R can be connected using the connecting member 50 without any additional processing being performed on the reducer 1 itself. This ensures freedom in the design of the reducer 1, and increases the versatility of the reducer 100 with a fall prevention function.

In the reducer 100 with a fall prevention function, the connecting member 50 is string-shaped. This allows the connecting member 50 to be easily and flexibly attached to the reducer 1 and the robot R.

The reducer 1 comprises a case 30 fixed to the robot R and a crankshaft 10A rotatably mounted on the case 30. A connecting member 50 connects the case 30 to the robot R. Therefore, when attaching the reducer 1 to the robot R, the connecting member 50 can be attached to the case 30 of the reducer 1 and the robot R at the same time, improving work efficiency.

The reducer 100 with anti-detachment function has a second through-hole 105B that is provided on the outer periphery of the case 30 and penetrates in the axial direction, and a fixing member 106 that is inserted into the second through-hole 105B and fixed to the case 30. A first connecting member 51 is attached to the fixing member 106. Therefore, because the connecting member 50 is attached to the fixing member 106 that is located on the outer periphery of the case 30, the connecting member 50 can be attached without interfering with the carrier part 4 (output shaft) of the reducer 1.

According to the above-described embodiment, the first connecting member 51 can be fixed using the fixing member 106, so that the first connecting member 51 can be easily fixed.
Furthermore, since the fixing member 106 can be attached to the reducer 1 having the through-hole 105 afterward, a dedicated design for the reducer 1 is not required.
Further safety can be ensured by providing a second through hole 105B in addition to the first through hole 105A and fixing the fixing member 106 to the second through hole 105B.

The connecting member 50 has a first connecting member 51 fixed to a fixing member 106. Because the first connecting member 51 is fixed by the fixing member 106, it is possible to prevent the reducer 1 from falling off the robot R. Because the worker can access the fixing member 106 from one side of the case 30 (either one end or the other end), the worker can easily install the first connecting member 51.

The connecting member 50 has a third connecting member 53 that is wrapped around and fixed to the through hole. This more reliably prevents the reducer 1 from falling off the robot R.

In addition, the outer periphery of the case 30 has a groove 107 formed to continue to the second through-hole 105B, in which the third connecting member 53 is embedded. That is, the outer periphery of the case 30 has the third connecting member 53 embedded in the groove 107 formed to continue to the second through-hole 105B. Therefore, when the reducer 1 is attached to the robot R, the third connecting member 53 does not interfere with the robot R, ensuring an aesthetic appearance. Furthermore, because the third connecting member 53 is embedded in the groove 107, wear of the third connecting member 53 can be suppressed, and therefore, detachment of the reducer 1 can be suppressed over a long period of time.
When the case 30 is fixed to the robot R, the third connecting member 53 is not pinched and crushed between the robot R and the case 30. Therefore, damage to the third connecting member 53 can be prevented.

The connecting member 50 has a second connecting member 52 fixed to the outer peripheral surface 108 of the case 30. Therefore, the reducer 100 with a fall-off prevention function can be confirmed from the appearance when viewed from the side.

Second Embodiment
Hereinafter, a reducer 200 with a fall-off prevention function according to the second embodiment will be described with reference to the drawings.
FIG. 5 is a perspective view of the reducer 200 with a disengagement prevention function according to the second embodiment. FIG. 6 is a cross-sectional perspective view of the reducer 200 with a disengagement prevention function according to the second embodiment. FIG. 6 shows the reducer 200 with a disengagement prevention function from a different direction than that shown in FIG. 5. FIG. 7 is a cross-sectional view taken along line VI-VI in FIG. 5. A cross-section different from that shown in FIG. 6 and that shown in FIG. 7 is shown. For convenience of explanation, the input shaft 208 and the other end of the hollow shaft 203 (crankshaft outer teeth 234) shown in FIG. 7 are omitted from FIG.

The differences between the first and second embodiments described above mainly relate to the speed reduction mechanism 240. Other components corresponding to those in the first embodiment described above will be assigned the same reference numerals, and their description may be omitted.

As shown in Figure 5, the reducer 200 with a fall prevention function according to the second embodiment includes a reducer 201 that reduces the rotation of a drive source that generates a rotational force and outputs the reduced rotation, and a connecting member 50 that connects the reducer 201 to a robot R (see Figure 2) that uses the reducer 201.

In this second embodiment, the connecting member 50 includes the first connecting member 51, second connecting member 52, and third connecting member 53 described above, as well as a fourth connecting member 54 that penetrates the hollow portion of the reducer 201.

[Reduction gear]
The reducer 201 is provided, for example, at a connecting portion of a pair of rotatably connected arms (a joint portion of the robot R). The reducer 201 reduces and outputs motor torque input from a motor (not shown) serving as a drive source.
The reducer 201 need not necessarily have the configuration described below, but may be any other device capable of changing the speed of the rotation of the drive source that generates the rotational force. For example, instead of the reducer 201, a speed increaser that increases the speed of the rotation of the drive source that generates the rotational force and outputs it may be used.

The reducer 201 is a so-called hollow transmission in which the hollow shaft 203 (described below) is hollow. The reducer 201 comprises a case 30 and a reduction mechanism 240. The case 30 comprises a main body 232 and a flange 34. In the description of the second embodiment, the side of the reducer 201 to which the drive source is connected is referred to as the input side, and the side to which a mechanism such as an arm that receives the output of the reducer 201 is connected is referred to as the output side. Specifically, the input side of the first embodiment shown in Figure 3 is located on the left side of Figure 3, and the input side of the second embodiment shown in Figure 7 is located on the right side of Figure 7.

The hollow shaft 203 is inserted into the through-hole 251a in the base plate portion 4a and the through-hole 252a in the end plate portion 4b. The hollow shaft 203 is supported by crank bearings 263 and 264, which serve as bearings, so that it can rotate about its axis relative to the carrier portion 4. In other words, the crank bearings 263 and 264 are arranged around the hollow shaft 203 and support the hollow shaft 203 so that it can rotate relative to the carrier portion 4.

In this second embodiment, a portion of the hollow shaft 203 extending axially inward by a predetermined length from one end is supported by the base plate portion 4a via a crank bearing 263, and a portion of the hollow shaft 203 extending axially inward by a predetermined length from the other end is supported by the end plate portion 4b via a crank bearing 264. The other end of the hollow shaft 203 protrudes from the case 30 and expands radially outward. Crank shaft outer teeth 234 are provided on the outer peripheral surface of the other end of the hollow shaft 203.

The hollow shaft 203 may or may not have an eccentric portion 230. In this embodiment, the eccentric portion 230 includes a first eccentric portion 230A and a second eccentric portion 230B, but is not limited to this.

The hollow shaft 203 has a hollow portion 233 that opens on at least one end in the axial direction. In this embodiment, the hollow portion 233 is provided so as to penetrate the hollow shaft 203 over the entire axial direction, and is open on both axial sides.

[Fourth connecting member]
5 to 7, the fourth connecting member 54 axially penetrates the hollow portion 233. The fourth connecting member 54 has a configuration similar to that of the above-described connecting member 50. Although not shown, both ends of the fourth connecting member 54 may be folded back to form a loop, which may be crimped and fixed, and the loop may be hooked onto a hook (not shown) of the robot R or the like.

Next, the operation of the reducer 201 will be explained. First, the input shaft 208 is rotated, for example, by driving a motor (not shown). The rotation of this input shaft 208 is transmitted to the hollow shaft 203. Because the number of teeth of the crankshaft external teeth 234 provided on the outer surface of the hollow shaft 203 is greater than the number of teeth of the external teeth 209 of the input shaft 208, the hollow shaft 203 rotates at a rotational speed reduced from the rotation of the input shaft 208.

As the hollow shaft 203 rotates, the first eccentric portion 230A and the second eccentric portion 230B of the hollow shaft 203 rotate eccentrically. As a result, the first oscillating gear member 241 oscillates and rotates while meshing with the internal pin 3 in conjunction with the eccentric rotation of the first eccentric portion 230A, and the second oscillating gear member 242 oscillates and rotates while meshing with the internal pin 3 in conjunction with the eccentric rotation of the second eccentric portion 230B.

The oscillating rotation of the first oscillating gear member 241 and the second oscillating gear member 242 is transmitted to the carrier unit 4 through the torque transmission pin 210. That is, because the torque transmission pin 210 is inserted into the through hole, when each oscillating gear member rotates while meshing with the internal tooth pin 3 of the outer cylinder 2 in accordance with the rotation of the hollow shaft 203, the position of the torque transmission pin 210 also moves around the axis of the outer cylinder 2. As a result, the entire carrier unit 4 rotates relative to the outer cylinder 2 at a rotational speed reduced from the input rotation. At this time, the fourth connecting member 54 is fixed to the robot R or the case 30 without interfering with the operation of the reducer 201.

In this embodiment, the connecting member 50 has a first connecting member 51, a second connecting member 52, and a third connecting member 53, so the same effects as in the first embodiment can be obtained.

[Action and effect]
In the above-described reducer 200 with a fall-off prevention function, the reducer 201 has a hollow shaft 203 that receives the rotation of the drive source and extends in the axial direction, and the connecting member 50 has a fourth connecting member 54 that penetrates the hollow shaft 203. In the above embodiment, the connecting member 50 has the fourth connecting member that penetrates the hollow portion 233 of the hollow shaft 203, thereby preventing the reducer 201 from falling off from the robot R. Furthermore, because the fourth connecting member penetrates the hollow portion, the reducer 201 can be prevented from falling off from the robot R even if the transmission case is damaged.
The hollow portion 233 of the hollow shaft 203 is used, for example, for routing wiring connected to a drive source, and at the same time, the hollow shaft 203 can be used to attach the fourth connecting member 54. Therefore, no additional processing is required to attach the fourth connecting member 54 to the reducer 201.

(Third embodiment)
Hereinafter, a reducer 300 with a fall-off prevention function according to the third embodiment will be described with reference to the drawings.
FIG. 8 is a schematic diagram of a robot R1 using a reducer 300 with a fall-off prevention function according to the third embodiment.

The reducer 300 with a disengagement prevention function has a plurality of transmissions (a first transmission 308, a second transmission 314, and a third transmission 320) provided on the robot R1. The transmissions 308, 314, and 320 are provided with a connecting member 50.
Here, the speed reducer 300 with a fall prevention function is considered to be part of the robot R1. Therefore, even if, for example, multiple transmissions are connected by the connecting member 50, the connecting member 50 satisfies the configuration of connecting the transmissions to the robot R1 using the transmissions.

Robot R1 comprises a fixed base 302 in contact with the installation surface, a rotating head 304 extending upward from the fixed base 302, multiple arms (first arm 310 and second arm 316) rotatably attached to the rotating head 304, an end effector E attached to the tip of the arm, and multiple transmissions (first transmission 308, second transmission 314, and third transmission 320). The first arm 310 is rotatably connected to the rotating head 304 via the multiple transmissions 308, 314, and 320, and the second arm 316 is rotatably connected to the first arm 310. Transmissions 308, 314, and 320 can be either reducer 1 or reducer 201, as described above, or reducer 1 and reducer 201 can be used in any combination. A detailed description is provided below.

A rotating head 304 is mounted on the fixed base 302 so as to be rotatable around the S-axis, and rotates around the S-axis via a first servo motor 306 and a first transmission 308 as drive sources. A first arm 310 is mounted above the rotating head 304 so as to be swingable back and forth around the L-axis, and swings back and forth around the L-axis via a second servo motor 312 and a second transmission 314 as drive sources. A second arm 316 is mounted above the first arm 310 so as to be swingable up and down around the U-axis, and swings up and down around the U-axis via a third servo motor 318 and a third transmission 320 as drive sources. With the above configuration, the end effector E can be driven in three dimensions.

In the speed reducer 300 with anti-detachment function, the connecting member 50 that connects multiple transmissions can be freely combined with the first connecting member 51, second connecting member 52, third connecting member 53, and fourth connecting member 54 described above. For example, the first transmission 308 can be fixed with the first connecting member 51, and the second transmission 314 can be fixed with the fourth connecting member 54. The combination of multiple transmissions connected by the connecting member 50 can be selected as appropriate.

Furthermore, by fastening the first transmission 308 provided on the fixed base 302 and the second transmission 314 provided on the rotating head 304 to the third transmission 320, the second arm 316 of the robot R1 is connected to the base (including the fixed base 302 and rotating head), preventing the second arm 316 from falling off.

[Action and effect]
In the above-described speed reducer 300 with a disengagement prevention function, a plurality of transmissions are provided on the robot R1, and the plurality of transmissions (first transmission 308, second transmission 314, and third transmission 320) are connected by a connecting member 50. By connecting the plurality of transmissions by the connecting member 50, it is possible to prevent the first transmission 308, second transmission 314, and third transmission 320 from disengaging from the robot R1, and also to prevent the transmissions from disengaging from each other.

In the above embodiment, a screw having a head 106A and a shaft 106B with a smaller diameter than the head 106A is used as the fixing member 106. However, this is not limited to this, and any member capable of fixing the reducer 100, 200, 300 with anti-detachment function to the robot R, R1 may be used. For example, a screw or the like may be used as the fixing member 106 instead of a screw.

In the first embodiment described above, the reducer 1 is configured to rotate the crankshaft 10A by rotating the input shaft 8 corresponding to the input gear 40B, and to oscillate and rotate the oscillating gears 14, 16 in conjunction with the eccentric portions 10a, 10b of the crankshaft 10A, thereby obtaining output rotation reduced from the input rotation. In the second embodiment described above, the reducer 201 is configured to include the outer cylinder 2 corresponding to the main body portion 232 (first cylindrical portion), the hollow shaft 203 having an axially hollow structure, the carrier portion 4, the first oscillating gear 14, the second oscillating gear 16, and the input shaft 208. However, this is not limited thereto, and the reducer 1, 201 may be any eccentric oscillating reducer that reduces the rotation of the crankshaft 10A and the eccentric portions 230A, 230B of the hollow shaft 203 provided within the case 30 and transmits the reduced rotation to the carrier portion 4, thereby causing the carrier portion 4 to rotate at a reduced speed relative to the rotation of the drive source.

In the above embodiment, the mating member is a robot, but this is not limited to this. The mating member may be a machine tool or other device, an unmanned guided vehicle such as an AGV, transportation equipment, or any other device that needs to be prevented from falling off.

Among the embodiments disclosed in this specification, those that are composed of multiple objects may be integrated, and conversely, those that are composed of a single object may be separated into multiple objects. Regardless of whether they are integrated or not, it is sufficient that they are configured in a way that allows the purpose of the invention to be achieved.

1, 201...Reduction gear, 4...Carrier portion (output shaft), 10A...Crankshaft, 30...Case, 50...Connecting member, 51...First connecting member, 52...Second connecting member, 53...Third connecting member, 54...Fourth connecting member, 100, 200, 300...Reduction gear with anti-detachment function (transmission with anti-detachment function), 106...Fixing member, 107...Groove, 203...Hollow shaft, 233...Hollow portion, O1...Axial direction, R, R1...Robot (mating member)

Claims (7)

a transmission having a case fixed to a mating member, which changes the speed of rotation of a drive source that generates a rotational force and outputs the rotation;
a through hole that penetrates the flange portion of the case in the axial direction;
a first fixing member that is inserted into the through hole and fixes the case and the mating member;
a second fixing member fixed to an outer peripheral surface of the flange portion along a direction intersecting the axial direction;
a connecting member that connects the transmission and the mating member;
Equipped with
The connecting member is
a first connecting member that connects the first fixing member and the mating member;
a second connecting member that connects the second fixing member and the mating member;
and
The first connecting member and the second connecting member maintain the connected state between the transmission and the mating member regardless of changes in the position of the transmission relative to the mating member. a transmission having a case fixed to a mating member, which changes the speed of rotation of a drive source that generates a rotational force and outputs the rotation;
a through hole that penetrates the flange portion of the case in the axial direction;
a fixing member inserted into the through hole and fixing the case and the mating member;
a connecting member that connects the transmission and the mating member;
Equipped with
the connecting member has a third connecting member wound around and fixed to the through hole,
The connecting member maintains the connected state between the transmission and the mating member regardless of a change in the position of the transmission relative to the mating member. a groove formed to be continuous with the through hole of the flange portion of the case and in which the third connecting member is embedded;
The transmission with a disengagement prevention function according to claim 2 . 4. The transmission with a disengagement prevention function according to claim 1, wherein the connecting member is string-shaped. a hollow shaft to which rotation of the drive source is input and which extends in the axial direction;
5. The transmission with a disengagement prevention function according to claim 1, wherein the connecting member has a fourth connecting member that penetrates the hollow shaft. The transmission with a disengagement prevention function according to claim 1 , wherein a plurality of the transmissions are provided on the mating member and connected by the connecting member. The transmission is
at least one crankshaft that is disposed within the case and rotates in response to rotation of the drive source;
an output shaft that is provided in the case and that reduces the rotation of the drive source and outputs the reduced rotation,
an eccentric oscillating reducer that reduces the rotation of the crankshaft and transmits it to the output shaft, causing the output shaft to rotate at a reduced speed relative to the rotation of the drive source;
The transmission with a disengagement prevention function according to any one of claims 1 to 6 .