JP7730372B2 - Brake and drive devices - Google Patents

Description

The present invention relates to a brake device and a drive device.
This application claims priority based on Japanese Patent Application No. 2021-137065, filed on August 25, 2021, the contents of which are incorporated herein by reference.

Drive devices used, for example, when welding parts to be welded, have been known for some time. A known example of a drive device is a positioner that changes the orientation of the parts to be welded to make welding easier. The positioner includes a base that holds the parts to be welded, a disk that is integral with the base and rotates the base, and a drive device that drives the disk to rotate. The drive device often includes an electric motor unit and a speed reducer that slows the rotation of the electric motor unit and outputs it to the disk. The electric motor unit is equipped with, for example, an electromagnetic brake. The electromagnetic brake prevents the electric motor unit from rotating unintentionally, thereby maintaining the rotational position of the disk and the posture of the base.

However, as the parts to be welded become larger, a large force may be applied to the disc depending on the position of the base. Under such circumstances, it is conceivable that the power supply to the drive unit may be cut off or some kind of malfunction may occur in the drive unit, making it impossible to maintain the rotational position of the disc (position of the base). In such a case, the disc may rotate suddenly, and the parts to be welded may be suddenly swung around. For this reason, drive units equipped with a brake device that applies a braking force to the disc, separate from an electromagnetic brake or the like, have been proposed.

A braking device technology has been disclosed in which a ring that rotates integrally with a disk or the like is attached to the disk, and a braking force is applied to the ring. Such a braking device includes a sliding rod that moves toward and away from the ring in the radial direction, a spring that urges the sliding rod toward the ring, and an operating arm that moves the sliding rod away from the ring against the spring force of the spring. A brake shoe is attached to the tip of the sliding rod.

With this configuration, operating the operating arm separates the sliding rod from the ring, releasing the braking force. Meanwhile, when the operating arm is released, the spring force of the spring elastically presses the sliding rod toward the ring. This generates a frictional force (braking force) between the ring and the brake shoe attached to the tip of the sliding rod.

Japanese Patent Application Publication No. 2011-236003

In the conventional technology described above, the spring force presses the sliding rod from the radial outside of the ring, thereby generating braking force. Therefore, to generate a large braking force, the spring must be made larger accordingly. Increasing the spring size increases the radial protrusion length of the brake device, potentially resulting in an increase in the overall size of the brake device.

The present invention provides a compact brake device and drive device that can generate large braking force.

A brake device according to one aspect of the present invention comprises a cam receiving portion provided on one surface normal to the rotational axis direction of a rotating body, a cam portion that contacts and moves away from the cam receiving portion, and a cam driving portion that drives the cam portion to rotate, and the cam portion contacts and moves away from the cam receiving portion as it rotates.

By configuring it in this way, the rotational force of the cam portion can be used to press the cam portion against the cam receiving portion. This creates a frictional force (braking force) between the cam receiving portion and the cam portion. In this way, the magnitude of the rotational force is the same as the magnitude of the braking force, so even when the braking force is increased, the brake device can be made smaller without, for example, increasing its radial length.

In the above configuration, the cam receiving portion has a brake surface whose surface direction is along the rotation axis, and the cam portion may contact and separate from the brake surface as it rotates.

In the above configuration, the braking surface may be formed in a circular shape centered on the rotation axis.

The cam portion may be elliptical in shape having a major axis and a minor axis perpendicular to the rotation axis of the cam portion, and the cam receiving portion may have the brake surfaces provided on the radially outer and inner sides of the rotating body, sandwiching the cam portion.

In the above configuration, the cam receiving portion may be a groove portion formed on one surface of the rotating body, and the inner surface of the groove portion may be the brake surface.

In the above configuration, the cam drive unit may have an electric motor unit.

In the above configuration, the rotation axis of the cam portion may be aligned with the rotation axis direction of the rotating body.

The above configuration may also be provided with a biasing portion that biases the brake surface in a direction that brings the cam portion into contact with the brake surface.

In the above configuration, the urging portion may include a cam side pressure plate provided on the cam portion, a drive side pressure plate provided on the cam drive portion, and an elastic member provided between the cam side pressure plate and the drive side pressure plate, which urges the cam side pressure plate in a direction around the rotation axis.

In the above configuration, the cam drive unit may rotate the cam portion against the biasing force of the biasing unit so that the cam portion does not contact the brake surface.

A brake device according to another aspect of the present invention comprises a cam receiving portion provided on one surface of a rotating body that rotates around a first rotational axis, the surface normal to the first rotational axis; a cam portion that rotates around a second rotational axis that runs along the first rotational axis and that contacts and moves away from the cam receiving portion; and a cam drive unit having an electric motor unit for driving the cam portion to rotate. The cam receiving portion has a brake surface that is formed concentrically with the first rotational axis and whose surface direction is along the first rotational axis. The cam portion has an elliptical shape with major and minor axes perpendicular to the second rotational axis, and contacts and moves away from the brake surface as the cam portion rotates.

With this configuration, the rotational force of the cam portion can be used to press the cam portion against the braking surface, thereby generating a frictional force (braking force) between the braking surface and the cam portion. In this way, the magnitude of the rotational force is the magnitude of the braking force, so even when the braking force is increased, the brake device can be made smaller without, for example, increasing its radial length.
Furthermore, the outer peripheral surface of the cam portion can be more easily brought into contact with both the radially outer braking surface and the radially inner braking surface at the same time, which allows for more efficient generation of braking force and further contributes to the miniaturization of the brake device.

A brake device according to another aspect of the present invention comprises a cam receiving portion provided on one surface of a rotor rotating about a first rotational axis, the normal direction of which is the first rotational axis, and having a brake surface formed concentrically with the first rotational axis and with a surface direction along the first rotational axis; a cam portion that rotates about a second rotational axis along the first rotational axis and contacts and separates from the cam receiving portion; a cam drive unit having an electric motor unit for rotationally driving the cam portion; and a biasing portion that biases the cam portion in the direction of contact with the brake surface, the biasing portion comprising a cam side pressure plate provided on the cam portion, a drive side pressure plate provided on the cam drive unit, and an elastic member provided between the cam side pressure plate and the drive side pressure plate that biases the cam side pressure plate in the direction around the second rotational axis, and the cam drive unit drives the cam portion to rotate against the biasing force of the biasing portion so that the cam portion does not contact the brake surface.

With this configuration, the rotational force of the cam portion can be used to press the cam portion against the braking surface, thereby generating a frictional force (braking force) between the braking surface and the cam portion. In this way, the magnitude of the rotational force is the magnitude of the braking force, so even when the braking force is increased, the brake device can be made smaller without, for example, increasing its radial length.
Furthermore, if the cam portion is rotated against the biasing force of the biasing portion so that it does not contact the brake surface while power is normally supplied to the cam drive portion, the following can be achieved: That is, if a malfunction occurs in the cam drive portion or if the power supply to the cam drive portion is cut off, the biasing force of the biasing portion will cause the cam portion to rotate, causing the outer circumferential surface of the cam portion to contact the brake surface. This allows the brake device to be reliably activated at the desired timing. The fail-safe function can be enhanced.

A drive device according to another aspect of the present invention comprises a rotor that rotates about a first rotational axis, a rotor drive device that rotationally drives the rotor, and a brake device that applies a braking force to the rotor. The brake device comprises a cam receiving portion provided on one surface of the rotor that rotates about the first rotational axis, the surface normal to the first rotational axis; a cam portion that rotates about a second rotational axis that runs along the first rotational axis and contacts and moves away from the cam receiving portion; and a cam drive portion that rotationally drives the cam portion. The cam receiving portion has a surface direction that runs along the first rotational axis and is formed concentrically with the first rotational axis, and has a brake surface that is positioned radially outward of the rotor than the rotor drive device, and the cam portion contacts and moves away from the brake surface as the rotor rotates.

In this way, by positioning the brake device radially outward from the rotor drive device, the brake device is more likely to generate a large braking torque. This makes it easier to miniaturize the brake device.

The above configuration may include a biasing unit that biases the cam portion in the direction in which the cam portion contacts the brake surface, and a main power source that supplies power to the rotating body drive device and the cam drive portion, and the biasing unit may include a cam side pressure plate provided on the cam portion, a drive side pressure plate provided on the cam drive portion, and an elastic member provided between the cam side pressure plate and the drive side pressure plate that biases the cam side pressure plate in the direction around the second rotation axis.

The above configuration may also include a detection unit that detects the power supply state of the main power supply that supplies power to the rotating body drive device or a failure of the rotating body drive device, a secondary power supply that supplies power to the cam drive unit, and a control unit that controls the drive of the cam drive unit based on the detection results of the detection unit.

The above-mentioned brake device and drive device can be made compact while still providing a large braking force.

1 is a perspective view of a drive device according to a first embodiment of the present invention; 1 is a side view of a brake device according to a first embodiment of the present invention, viewed from an X direction. FIG. 2 is a schematic configuration diagram of a speed reducer unit according to the first embodiment of the present invention. FIG. 4 is a plan view of a cam portion according to the first embodiment of the present invention, as viewed from the Y direction. 5A to 5C are explanatory diagrams showing the behavior of a cam portion in the first embodiment of the present invention. 10A and 10B are explanatory diagrams showing the behavior of a cam portion in a modified example of the first embodiment of the present invention. FIG. 10 is a block diagram showing a drive device according to a second embodiment of the present invention.

Next, an embodiment of the present invention will be described based on the drawings.

[First embodiment]
<Drive unit>
FIG. 1 is a perspective view of a drive device 1. FIG.
1, the driving device 1 is a so-called positioner that holds a workpiece W and changes the orientation of the workpiece W to, for example, an orientation that makes it easier to weld the workpiece W. An example of the workpiece W is a bucket of a shovel, which is a construction machine.

The drive device 1 comprises a support portion 2, a disk portion (an example of a rotating body in the claims) 3, a disk drive device (an example of a rotating body drive device in the claims) 4, a brake device 5, a tilt arm 6, a rotary table 7, and a control unit 30. The disk portion 3 is rotatably supported on the support portion 2. The disk drive device 4 drives the disk portion 3 to rotate. The brake device 5 applies a braking force to the disk portion 3. The tilt arm 6 is provided on the disk portion 3. The rotary table 7 is provided on the tilt arm 6. The control unit 30 controls the drive of the disk drive device 4, brake device 5, and rotary table 7.

<Support part>
The support unit 2 includes two base frames 8, 9 arranged on the floor F and support columns 10 rising from the base frames 8, 9. The two base frames 8, 9 are rectangular pipe-shaped members that are long in one direction. The two base frames 8, 9 are arranged side by side in parallel. In the following description, the direction in which the two base frames 8, 9 are lined up may be referred to as the X direction, the longitudinal direction of the two base frames 8, 9 as the Y direction, and the up and down direction of gravity (vertical direction) as the Z direction. The up and down direction of gravity may also be simply referred to as the up and down directions. The X-Y directions are aligned horizontally.

The support pillar 10 is connected to one longitudinal end 8a, 9a of the two base frames 8, 9. The support pillar 10 rises from the base frames 8, 9 along the Z direction. When viewed from the Z direction, the support pillar 10 is a rectangular parallelepiped pillar that is long in the X direction. The upper part 10a of the support pillar 10 has a flange portion 11 on the surface 10b facing each of the base frames 8, 9.

The flange portion 11 is a square-shaped plate member when viewed from the Y direction. That is, the plate thickness direction of the flange portion 11 coincides with the Y direction, and it has an upper surface 11a and a lower surface 11b that face each other in the vertical direction, and two vertical side surfaces 11c that face each other in the X direction. The flange portion 11 is fixed to the support 10, for example, by welding. One of the two vertical side surfaces 11c has a mounting recess 11f formed therein for mounting the disk drive device 4. The disk portion 3 is rotatably supported on a first surface 11d of the flange portion 11 opposite the support 10.

<Disc section>
The disk portion 3 is a circular disk that is larger than the flange portion 11 when viewed from the Y direction. A disk rotation axis C1 (an example of a rotation axis in the claims) of the disk portion 3 coincides with the Y direction. The thickness direction of the disk portion 3 coincides with the Y direction. In other words, the normal directions of both surfaces 3a, 3b (first surface 3a, second surface 3b) of the disk portion 3 coincide with the Y direction. Furthermore, the disk rotation axis C1 is located approximately in the center of the flange portion 11 when viewed from the Y direction.

A circular cam receiving groove 12 (an example of a cam receiving portion in the claims) is formed on a first surface 3a (an example of a surface in the claims) on the flange 11 side of the disk portion 3. The cam receiving groove 12 is formed to a size that surrounds the outside of the flange 11 when viewed from the Y direction.
The cam receiving groove portion 12 has a bottom surface 12a, a first inner surface (an example of a brake surface or inner surface in the claims) 12b, and a second inner surface (an example of a brake surface or inner surface in the claims) 12c. The bottom surface 12a is parallel to the first surface 3a of the disc portion 3. The first inner surface 12b rises from the radially outer side of the bottom surface 12a of the disc portion 3. The second inner surface 12c rises from the radially inner side of the bottom surface 12a of the disc portion 3.

That is, the first inner surface 12b and the second inner surface 12c face each other in the radial direction. The surface direction of the first inner surface 12b and the surface direction of the second inner surface 12c are aligned along the direction of the disc rotation axis C1. A braking force is applied to this cam receiving groove portion 12 by the brake device 5. Details of the brake device 5 will be described later.

<Tilt arm>
The tilt arm 6 is formed in the shape of a plate that is long in the Y direction. A first longitudinal end 6a of the tilt arm 6 is fixed to a second surface 3b opposite the flange portion 11 of the disk portion 3. A rotary table 7 is provided on a first surface 6c in the plate thickness direction at the second longitudinal end 6b of the tilt arm 6 opposite the disk portion 3.

<Rotary table>
The rotary table 7 is rotatably mounted relative to the tilt arm 6. A table rotation axis C2 of the rotary table 7 coincides with the thickness direction of the tilt arm 6. The rotary table 7 is driven to rotate relative to the tilt arm 6 by a table drive device (not shown). The table drive device includes, for example, an electric motor unit (not shown) and a speed reducer unit that reduces the rotation of the motor shaft of the electric motor unit and outputs the reduced rotation.

The electric motor unit is connected to the control unit 30. The control unit 30 is equipped with a main power supply 30a, which supplies power to the electric motor unit and controls the drive of the electric motor unit 16. The electric motor unit is also equipped with, for example, an electromagnetic brake.

The output of the speed reducer is transmitted to the rotary table 7. As a result, the rotary table 7 is driven to rotate.
A workpiece holder 13 is attached to the rotary table 7. The workpiece holder 13 is rotated integrally with the rotary table 7. A workpiece W is fixed to the workpiece holder 13. This causes the rotary table 7 to rotate the workpiece W around the table rotation axis C2.

<Disk drive device>
The disk drive device 4 is accommodated radially inside the cam receiving groove portion 12 when viewed from the Y direction. The disk drive device 4 includes a drive device main body 14 that is attached to the attachment recess 11f of the flange portion 11 and generates a rotational driving force, and a transmission mechanism 15 that transmits the rotational driving force of the drive device main body 14 to the disk portion 3. The drive device main body 14 includes an electric motor unit 16 and a speed reducer unit 17. The electric motor unit 16 is attached to the attachment recess 11f of the flange portion 11. The speed reducer unit 17 is provided coaxially with a rotation axis C3 of the electric motor unit 16 (hereinafter referred to as the drive device rotation axis) and on the disk portion 3 side of the electric motor unit 16.

The drive unit rotation axis C3 is parallel to the disc rotation axis C1. The basic configuration of the drive unit main body 14 is the same as that of a cam drive unit 21 (described later) of the brake device 5. For this reason, the description of the drive unit main body 14 will be simplified and will be given in detail with respect to the cam drive unit 21 (described later).
The electric motor unit 16 is connected to the control unit 30. The electric motor unit 16 is supplied with power from a main power supply 30a of the control unit 30 and is drive-controlled by the control unit 30. The electric motor unit 16 also includes, for example, an electromagnetic brake (not shown). The electromagnetic brake applies a braking force to a motor shaft (not shown) of the electric motor unit 16. A speed reducer 17 is connected to this motor shaft.

The speed reducer 17 reduces the rotation input from the motor shaft and outputs it. The speed reducer 17 may be, for example, a so-called eccentric oscillating type speed reducer having a crankshaft to which the rotation of the motor shaft is input and an external gear (neither shown) that oscillates and rotates in conjunction with the rotation of the crankshaft. The eccentric oscillating type speed reducer obtains reduced output rotation from the rotation of the motor shaft by the oscillating rotation of the external gear.

The transmission mechanism 15 includes a first spur gear 18 and a second spur gear 19. The first spur gear 18 is fixed to an output section (carrier 32, described below) of the reduction gear unit 17, not shown, and rotates integrally with this output section. The second spur gear 19 is fixed to the first surface 3a of the disk unit 3 and meshes with the first spur gear 18. The second spur gear 19 is arranged coaxially with the disk rotation axis C1. The rotation of the electric motor unit 16 is transmitted to the disk unit 3 via the first spur gear 18 and the second spur gear 19. This causes the disk unit 3 to rotate about the disk rotation axis C1.

<Brake device>
Fig. 2 is a side view of the braking device 5 as viewed from the X direction. Fig. 3 is a schematic diagram of the speed reducer 24 of the braking device 5.
1 to 3, the brake device 5 is attached to the upper surface 11a of the flange portion 11 via a bracket 20. The bracket 20 is formed in an L-shape. The bracket 20 has a base plate 20a fixed to the upper surface 11a of the flange portion 11 and a support plate 20b rising from the edge of the base plate 20a on the side of the disk portion 3.

When viewed from the Y direction, a circular opening 20e is formed in the center of the support plate 20b. A plurality of bolt insertion holes 20f penetrating the support plate 20b in the plate thickness direction are formed around the opening 20e at equal intervals around the circumferential direction. Bolts 25 are inserted into these bolt insertion holes 20f from the side of the support plate 20b opposite the disk portion 3 (the right side in Figures 2 and 3). These bolts 25 secure the brake device 5 to the first surface 20c of the support plate 20b on the disk portion 3 side.

The brake device 5 includes a cam drive unit 21 and a cam unit 22 attached to the cam drive unit 21. The cam drive unit 21 includes an electric motor unit 23 and a reduction unit 24 that is coaxial with the rotation axis C4 of the electric motor unit 23 (hereinafter referred to as the brake device rotation axis) and is provided on the disk unit 3 side of the electric motor unit 16. The reduction unit 24 is fixed to the first surface 20c of the support plate 20b by a plurality of bolts 25.

The brake device rotation axis C4 and the opening 20e in the support plate 20b are arranged coaxially. The electric motor unit 23 protrudes through this opening 20e from the first surface 20c of the support plate 20b toward the second surface 20d opposite the first surface 20c. When the brake device 5 is attached to the support plate 20b, the brake device rotation axis C4 is parallel to the disc rotation axis C1 and the drive device rotation axis C3.

Like the electric motor unit 16 of the disk drive device 4, the electric motor unit 23 is connected to the control unit 30. The electric motor unit 23 is supplied with power from the main power supply 30a of the control unit 30 and is drive-controlled by the control unit 30. The motor shaft 23a of the electric motor unit 23 is formed with external teeth 23b for transmitting the rotation of the motor shaft 23a to the reduction unit 24. In the following description of the brake device 5, unless otherwise specified, the axial direction will be referred to as the brake device rotation axis C4. The radial direction will be referred to as the radial direction of the motor shaft 23a. The circumferential direction will be referred to as the rotation direction of the motor shaft 23a (the direction around the brake device rotation axis C4).

The speed reducer 24 includes a cylindrical case 31, an output unit (carrier 32), and a mechanism 33. The output unit is disposed radially inside the case 31. The mechanism 33 rotates the carrier 32 at a rotation speed that is reduced by a fixed ratio relative to the rotation speed of the motor shaft 23 a.
A plurality of female screw portions 31a are formed at equal intervals in the circumferential direction on the outer peripheral surface of the case 31 on the support plate 20b side. These female screw portions 31a communicate with bolt insertion holes 20f in the support plate 20b, and bolts 25 are fastened to these female screw portions 31a.

An outer flange portion 34 is integrally formed on the outer peripheral surface of the case 31, projecting radially outward toward the disk portion 3 (left side in Figures 2 and 3). Multiple (e.g., four in this first embodiment) drive-side pressure plates 35 are provided on one surface 34a of the outer flange portion 34 facing the disk portion 3, protruding toward the disk portion 3. The multiple drive-side pressure plates 35 are arranged at equal intervals in the circumferential direction. The thickness direction of the drive-side pressure plates 35 is aligned with the circumferential direction. The drive-side pressure plates 35 form part of the biasing portion 28 that generates a biasing force in the circumferential direction on the cam portion 22. Details of the biasing portion 28 will be described later.

Internal teeth 36 are provided on the inner peripheral surface of the case 31. The internal teeth 36 are pin-shaped (cylindrical) teeth provided on the inner peripheral surface of the case 31. Multiple internal teeth 36 are arranged at equal intervals in the circumferential direction.

The carrier 32 is rotatably supported on the case 31 by a pair of main bearings 37 spaced apart in the axial direction. The main bearings 37 are, for example, angular contact ball bearings. The carrier 32 is arranged coaxially with the case 31 and the brake device rotation axis C4.
The carrier 32 includes a base portion 38, an end plate portion 39, and three cylindrical pillar portions 40. The base portion 38 is disposed on the support plate 20b side. The end plate portion 39 is disposed on the disk portion 3 side. The three pillar portions 40 are integrally molded with the base portion 38 and protrude from the base portion 38 toward the end plate portion 39.

The column portions 40 are arranged at equal intervals around the circumference. An end plate portion 39 is disposed at the tip 40a of the column portion 40. A female thread portion 40b is formed on the column portion 40. Meanwhile, a bolt insertion hole 39a that leads to the female thread portion 40b is formed on the end plate portion 39 at a location corresponding to the female thread portion 40b. A bolt 29 is inserted into the bolt insertion hole 39a from the disk portion 3 side of the end plate portion 39, and the bolt 29 is tightened into the female thread portion 40b of the column portion 40. This fastens the end plate portion 39 to the column portion 40. In this state, a space of a certain width in the axial direction is formed between the base portion 38 and the end plate portion 39.

A pin 41 for positioning the end plate 39 is provided on the pillar 40 slightly radially inward of the bolt 29. The pin 41 is positioned so as to straddle the pillar 40 and the end plate 39. Note that the pillar 40 does not have to be formed integrally with the base plate 38. In this case, the pillar 40 is fastened to the base plate 38. Furthermore, the pillar 40 is not limited to being cylindrical. It is sufficient that the pillar 40 forms a space with a certain width in the axial direction between the base plate 38 and the end plate 39.

The end plate portion 39 and the base plate portion 38 each have a plurality of crankshaft insertion holes 39b, 38a (for example, three in this first embodiment) into which the crankshaft 43 (described later) of the mechanism portion 33 is inserted. The crankshaft insertion holes 39b, 38a axially penetrate the corresponding end plate portion 39 and base plate portion 38. The crankshaft insertion holes 39b, 38a are arranged at equal intervals in the circumferential direction.

The mechanism 33 includes a plurality of transmission gears 42 (e.g., three in this first embodiment), a plurality of crankshafts 43 (e.g., three in this embodiment), a first external gear 44, and a second external gear 45. The transmission gears 42 are meshed with the external teeth 23b of the motor shaft 23a. One ends of the crankshafts 43 are fixed to the transmission gears 42 and are rotatably supported on the end plate portion 39 and the base portion 38. The first external gear 44 and the second external gear 45 oscillate and rotate in conjunction with the rotation of the crankshaft 43. Because the transmission gear 42 is fixed to one end of the crankshaft 43, the rotation of the motor shaft 23a is transmitted to the crankshaft 43 via the transmission gear 42.

The crankshaft 43 is arranged along the axial direction. That is, the crankshaft 43 rotates around a crank rotation axis C5 that is parallel to the brake device rotation axis C4. The crankshaft 43 is rotatably supported on the base plate portion 38 via a first crank bearing 46 provided in the crankshaft insertion hole 38a of the base plate portion 38. The crankshaft 43 is rotatably supported on the end plate portion 39 via a second crank bearing 47 provided in the crankshaft insertion hole 39b of the end plate portion 39. The first crank bearing 46 and the second crank bearing 47 are, for example, tapered roller bearings.

A first eccentric portion 48a and a second eccentric portion 48b are formed at the axial center of the crankshaft 43, and are eccentric from the axis of the crankshaft 43. The first eccentric portion 48a and the second eccentric portion 48b are arranged adjacent to each other in the axial direction between the first crank bearing 46 and the second crank bearing 47. The first eccentric portion 48a and the second eccentric portion 48b are shifted in phase angle from each other.

A first roller bearing 49a is attached to the first eccentric portion 48a. A second roller bearing 49b is attached to the second eccentric portion 48b. These roller bearings 49a, 49b are, for example, cylindrical roller bearings. The first external gear 44 and the second external gear 45 are rotatably supported via the roller bearings 49a, 49b.

The first external gear 44 and the second external gear 45 are disposed in the space between the base plate portion 38 and the end plate portion 39 of the carrier 32. The first external gear 44 and the second external gear 45 have external teeth 44 a, 45 a that mesh with the internal teeth 36 of the case 31.
The first external gear 44 and the second external gear 45 are formed with column insertion holes 44b, 45b into which the column 40 is inserted, and crankshaft insertion holes 44c, 45c into which each eccentric portion 48a, 48b of the crankshaft 43 is inserted.

The first eccentric portion 48a and first roller bearing 49a of the crankshaft 43 are inserted into the crankshaft insertion hole 44c of the first external gear 44. The second eccentric portion 48b and second roller bearing 49b of the crankshaft 43 are inserted into the crankshaft insertion hole 45c of the second external gear 45. As a result, the first eccentric portion 48a and the second eccentric portion 48b are oscillated and rotated by the rotation of the crankshaft 43. Accordingly, the first external gear 44 and the second external gear 45 are oscillated and rotated while meshing with the internal teeth 36 of the case 31. The column portion insertion holes 44b, 45b of the first external gear 44 and the second external gear 45 are sized so that the external gears 44, 45 do not interfere with the column portion 40 during the oscillating rotation of each external gear 44, 45.

FIG. 4 is a plan view of the cam portion 22 as viewed from the Y direction.
2 to 4, the cam portion 22 is disposed on one surface 39c of the end plate portion 39 on the side of the disc portion 3. The cam portion 22 is a block body formed in an elliptical shape having a major axis and a minor axis when viewed from the Y direction. The center C6 of the cam portion 22 when viewed from the Y direction coincides with the brake device rotation axis C4.

The cam portion 22 has a bolt insertion hole 22a formed in a location corresponding to the bolt insertion hole 39a in the end plate portion 39 (the female thread portion 40b of the column portion 40), which leads to the bolt insertion hole 39a. A bolt 29 is inserted into each bolt insertion hole 22a, 39a from the disk portion 3 side of the cam portion 22, and the bolt 29 is tightened into the female thread portion 40b of the column portion 40. This fastens and secures the cam portion 22 and end plate portion 39 to the column portion 40. A counterbore portion 22b is formed in the bolt insertion hole 22a formed in the cam portion 22. Therefore, the head 29a of the bolt 29 does not protrude from the first surface 22c of the cam portion 22 on the disk portion 3 side.

Friction material 50 is provided on most of the outer peripheral surface 22d of the cam portion 22 on both sides in the longitudinal direction. The friction material 50 is, for example, a strip-shaped body with a rough surface. The friction material 50 is attached to the outer peripheral surface 22d of the cam portion 22 with, for example, an adhesive (not shown). However, this is not limited to this. The friction material 50 may be formed from a thin steel plate and fixed to the outer peripheral surface 22d of the cam portion 22 with bolts (not shown). In this case, it is preferable to use flat head screws or the like so that the bolt heads do not protrude. Note that the scale of the friction material 50 has been altered in Figure 4 for ease of explanation.

On the second surface 22e of the cam section 22 facing the deceleration section 17, multiple (for example, four in this first embodiment) cam side pressure plates 51 are provided protruding toward the deceleration section 17 at locations corresponding to the drive side pressure plates 35 provided on the case 31. The multiple cam side pressure plates 51 are arranged at equal intervals in the circumferential direction. The thickness direction of the cam side pressure plates 51 is along the circumferential direction. The cam side pressure plates 51 face the drive side pressure plates 35 in the circumferential direction. Coil springs 52 are provided between these cam side pressure plates 51 and the drive side pressure plates 35 in a slightly compressed state.

The driving-side pressure plate 35, the cam-side pressure plate 51, and the coil spring 52 constitute the biasing portion 28. The spring force (restoring force) of the coil spring 52 generates a biasing force on the pressure plates 35, 51 of the biasing portion 28 in directions that move them away from each other. In other words, the biasing portion 28 generates a biasing force on the cam portion 22 in the circumferential direction.

With this configuration, the brake device 5 is disposed so that the cam portion 22 faces the cam receiving groove 12 of the disk portion 3. The groove width H of the cam receiving groove 12 (see FIGS. 1 and 5) is such that the outer peripheral surface 22d of the cam portion 22 presses against the inner surfaces 12b, 12c of the cam receiving groove 12 when the major axis of the cam portion 22 is aligned along the Z direction (along the radial direction of the disk portion 3). This causes the brake device 5 to apply a braking force to the disk portion 3. The operation of the brake device 5 and the drive unit 1 in which this brake device 5 is provided will be described in detail below.
In the disk drive device 4 , the first spur gear 18 of the transmission mechanism 15 is fixed to the output portion (carrier 32 ) of the drive device main body 14 in place of the cam portion 22 .

<Operation of Brake Device and Drive Device>
Next, the operation of the brake device 5 and the drive device 1 will be described.
Fig. 5 is an explanatory diagram showing the behavior of the cam portion 22 of the brake device 5. Fig. 5 corresponds to a plan view of the disk portion 3 as seen from the flange portion 11 side in the Y direction.
5, in the brake device 5, when the power supply from the control unit 30 to the electric motor unit 23 is cut off (the brake device 5 is in a non-driving state), the cam-side pressing plate 51 is urged in a direction away from the driving-side pressing plate 35 in the circumferential direction by the spring force of the coil spring 52 in the urging unit 28. In this state, the longitudinal direction of the cam unit 22 is aligned with the Z direction.

As a result, both longitudinal sides of the outer peripheral surface 22d of the cam portion 22 are pressed against the inner surfaces 12b, 12c of the cam receiving groove portion 12 formed in the disc portion 3. In other words, a pressing force acts on the inner surfaces 12b, 12c of the cam portion 22 in the radial direction. This generates a frictional force between the inner surfaces 12b, 12c of the cam receiving groove portion 12 and the cam portion 22. This frictional force acts as a braking force on the disc portion 3.

In this way, each inner surface 12b, 12c of the cam receiving groove portion 12 is a circular braking surface whose surface direction is along the disc rotation axis C1 and whose center is the disc rotation axis C1. The cam portion 22 generates a braking force by contacting each inner surface 12b, 12c, which is the braking surface.

The friction material 50 is provided on most of the outer peripheral surface 22d of the cam portion 22 on both sides in the longitudinal direction. This increases the friction force between the inner surfaces 12b, 12c and the outer peripheral surface 22d of the cam portion 22. As a result, a greater braking force is applied to the disc portion 3.
Moreover, the cam receiving groove portion 12 is disposed radially outward of the disk drive device 4. Therefore, it is easy to obtain a large braking torque by the brake device 5.

As shown in Figures 2 and 3, when driving the drive unit 1, the brake unit 5 is first driven to release the braking force applied to the disc unit 3 (hereinafter referred to as brake release). That is, the control unit 30 energizes the electric motor unit 23, and the motor shaft 23a of the electric motor unit 23 is rotated based on a control signal from the control unit 30. The rotation of the motor shaft 23a rotates the transmission gear 42, which is engaged with the external teeth 23b of the motor shaft 23a. This causes the crankshaft 43 to rotate integrally with the transmission gear 42 about the crank rotation axis C5.

When the crankshaft 43 rotates, the first external gear 44 rotates while meshing with the internal teeth 36 in response to the oscillation of the first eccentric portion 48a. Furthermore, the second external gear 45 rotates while meshing with the internal teeth 36 in response to the oscillation of the second eccentric portion 48b. In other words, the crankshaft 43 rotates about the crank rotation axis C5 and revolves around the brake device rotation axis C4.

As the crankshaft 43 revolves, the carrier 32 (base plate portion 38, end plate portion 39, pillar portion 40) that supports the crankshaft 43 so that it can rotate freely rotates around the brake device rotation axis C4 at a rotational speed that is slower than the rotational speed of the motor shaft 23a.
The case 31 is fixed to the support plate 20b of the bracket 20 by bolts 25. Meanwhile, the cam portion 22 is fixed to the end plate portion 39 of the carrier 32 by bolts 29. Therefore, when the motor shaft 23a rotates, the cam portion 22 rotates relative to the case 31 around the brake device rotation axis C4 (center C6).

The rotation direction of the motor shaft 23a is a direction that brings the cam side pressure plate 51 closer to the drive side pressure plate 35 of the case 31. As the motor shaft 23a rotates, the cam portion 22 rotates in a direction that brings the cam side pressure plate 51 closer to the drive side pressure plate 35 against the spring force of the coil spring 52. As a result, the longitudinal axis of the cam portion 22 tilts relative to the Z direction, as shown by the two-dot chain line in Figure 5. This separates the outer peripheral surface 22d of the cam portion 22 from the inner surfaces 12b, 12c of the cam receiving groove portion 12, releasing the brake.

With the brake released, the drive unit main body 14 of the disk drive device 4 is driven. The basic configuration of the drive unit main body 14 is the same as that of the cam drive unit 21 of the brake device 5, so a description of the operation of the drive unit main body 14 will be omitted. When the drive unit main body 14 is driven, the rotation of the drive unit main body 14 (electric motor unit 16) is transmitted to the disk unit 3 via the transmission mechanism 15. This causes the disk unit 3 to rotate around the disk rotation axis C1.

When the disk unit 3 rotates, the tilt arm 6 rotates integrally with the disk unit 3. This changes the posture of the workpiece W held by the tilt arm 6 via the rotary table 7. The control unit 30 also controls the drive of the rotary table 7. The workpiece W is also rotated by the rotary table 7 around the table rotation axis C2, changing its posture. In this way, the workpiece W can be changed into various postures by being rotated around the disk rotation axis C1 and the table rotation axis C2. This makes it easier to perform welding work on the workpiece W, for example.

Here, the posture of the workpiece W is maintained by an electromagnetic brake provided on a table drive device (not shown) of the rotary table 7 or an electromagnetic brake provided on the electric motor unit 16 of the disk drive unit 4. In addition, the rotational position of the disk unit 3 can also be maintained by the brake unit 5.
2 and 5, when the brake device 5 is put into a non-driven state, the spring force of the coil spring 52 separates the cam-side pressure plate 51 from the drive-side pressure plate 35. Accordingly, the cam portion 22 rotates so that the longitudinal axis of the cam portion 22 is aligned with the Z direction (along the radial direction of the disk portion 3) (see arrow Y1 in FIG. 5). As a result, a braking force is applied to the disk portion 3, preventing unintended rotation of the disk portion 3.

The action of the brake device 5 also functions as a fail-safe in the event of a malfunction in the main power supply 30a of the control unit 30, for example. For example, suppose that the disk drive device 4 stops functioning when power from the main power supply 30a is cut off. In such a case, the brake device 5 also goes into a non-operating state at the same time, applying a braking force to the disk unit 3. This prevents the disk unit 3 from rotating unintentionally.

In the first embodiment described above, the brake device 5 includes a cam receiving groove portion 12, a cam portion 22, and a cam drive portion 21. The cam receiving groove portion 12 is provided on the first surface 3a of the disc portion 3. The cam portion 22 contacts and separates from the cam receiving groove portion 12. The cam drive portion 21 drives the cam portion 22 to rotate. The cam drive portion 21 drives the cam portion 22 to rotate, pressing the cam portion 22 against the cam receiving groove portion 12. This generates a frictional force (braking force) between the cam receiving groove portion 12 and the cam portion 22. In this way, the magnitude of the rotational force of the cam portion 22 can be set to the magnitude of the braking force. Therefore, even if the coil spring 52 is enlarged to increase the braking force, the brake device 5 can be made smaller without becoming longer radially.

The cam receiving groove 12 has inner side surfaces 12b and 12c, the surface direction of which is along the disc rotation axis C1, serving as brake surfaces against which the cam portion 22 is pressed. In other words, the pressing force of the cam portion 22 against the cam receiving groove 12 acts in the radial direction.
Here, for example, if the pressing force of the cam portion 22 on the cam receiving groove portion 12 is applied in the direction of the disk rotation axis C1, it is necessary to increase the mechanical strength of the disk portion 3 so that it can withstand this pressing force. Specifically, it is necessary to increase the thickness of the disk portion 3 so that the disk portion 3 does not bend. However, by applying the pressing force of the cam portion 22 on the cam receiving groove portion 12 in the radial direction, it is possible to easily increase the mechanical strength of the disk portion 3 against the pressing force of the cam portion 22. In other words, even if the thickness of the disk portion 3 is reduced, the disk portion 3 will not bend. Therefore, the disk portion 3 can be made thinner.

Furthermore, each inner surface 12b, 12c of the cam receiving groove portion 12 is a circular braking surface centered on the disc rotation axis C1. Therefore, the cam portion 22 can contact each inner surface 12b, 12c regardless of the rotational position of the disc portion 3. This makes it possible to provide a brake device 5 with even greater safety.

The cam portion 22 is a block body formed in an elliptical shape with a major axis and a minor axis when viewed in the Y direction. This allows the outer peripheral surface 22d of the cam portion 22 to easily and reliably contact each of the inner surfaces 12b, 12c of the cam receiving groove portion 12. This allows braking force to be generated more efficiently on the disc portion 3, thereby enabling the brake device 5 to be made more compact.

A cam receiving groove 12 is provided in the disc portion 3, and the inner surfaces 12b, 12c formed thereby serve as braking surfaces against which the cam portion 22 is pressed. This makes it easy to provide a cam receiving portion in the disc portion 3 with which the cam portion 22 comes into contact and separates, allowing for the cam receiving portion to be made smaller. Furthermore, the pressing force of the cam portion 22 can be reliably received by the inner surfaces 12b, 12c, which form the braking surfaces. This provides a brake device 5 that efficiently generates braking force in the disc portion 3 and can be made smaller.

The cam drive unit 21 that rotates the cam unit 22 includes an electric motor unit 23. By electrifying the cam drive unit 21 in this way, the cam drive unit 21 can have a simpler structure and can be made smaller than when it is driven by hydraulic pressure, for example.
The rotation axis of the cam portion 22 (brake device rotation axis C4) is parallel to the disc rotation axis C1. Therefore, the rotational force of the cam portion 22 can be transmitted to each of the inner surfaces 12b, 12c more efficiently than in a case where the brake device rotation axis C4 intersects with the disc rotation axis C1. This allows the brake device 5 to be further miniaturized.

The brake device 5 is equipped with a biasing portion 28 that biases the outer peripheral surface 22d of the cam portion 22 in a direction that brings the outer peripheral surface 22d into contact with each of the inner surfaces 12b, 12c. When the brake device 5 is energized, the cam portion 22 is rotated against the spring force of the biasing portion 28. This configuration allows the cam portion 22 to rotate due to the spring force of the biasing portion 28 if a malfunction occurs in the cam drive portion 21 or if the power supply to the cam drive portion 21 is interrupted. The outer peripheral surface 22d of the cam portion 22 can then be brought into contact with each of the inner surfaces 12b, 12c. This ensures that the brake device 5 can be reliably activated at the desired timing. This enhances the fail-safe function of the brake device 5.

The biasing portion 28 is composed of a drive-side pressing plate 35, a cam-side pressing plate 51, and a coil spring 52. With such a simple configuration, it is possible to bias the outer peripheral surface 22d of the cam portion 22 in a direction that brings the inner surfaces 12b and 12c into contact with the outer peripheral surface 22d of the cam portion 22.
Such biasing portion 28 prevents the outer peripheral surface 22d of the cam portion 22 from coming into contact with the inner surfaces 12b, 12c when current is applied to the brake device 5. This ensures that braking force is generated on the disk portion 3 at the desired timing to activate the brake device 5, for example, during a power outage when the electromagnetic brake is not applied to the disk drive device 4. This improves the fail-safe function of the brake device 5.

The drive device 1 includes a disk drive device 4 that rotates the disk portion 3. The disk drive device 4 is located radially inside the cam receiving groove portion 12 when viewed from the Y direction. In other words, the cam receiving groove portion 12 is positioned radially outside the disk drive device 4. This allows a large braking torque to be obtained by the brake device 5, and the brake device 5 can be easily made smaller.

The disk drive device 4, brake device 5, and rotary table 7 of the drive device 1 are driven and controlled by a control unit 30 equipped with a main power supply 30a. Therefore, even if a malfunction occurs in the control unit 30 (main power supply 30a), that is, when the brake device 5 is not in operation, the brake device 5 can be reliably operated.

In the first embodiment described above, the pressing plates 35, 51 of the biasing portion 28 are circumferentially opposed to each other. A coil spring 52 is provided between these pressing plates 35, 51 in a slightly compressed state, thereby biasing the cam portion 22 in a direction that brings it into contact with the inner surfaces 12b, 12c of the cam receiving groove portion 12. However, this is not limited to this, and the biasing portion 28 may be configured to bias the cam portion 22 in the rotational direction.

For example, the retaining plates 35, 51 of the biasing portion 28 do not have to face each other in the circumferential direction. The retaining plates 35, 51 may be positioned offset in the radial direction of the disk portion 3. An elastic member may be provided between the retaining plates 35, 51, and this elastic member may bias the cam portion 22 in the rotational direction. The elastic member does not have to be the coil spring 52. Instead of the coil spring 52, various elastic members such as a leaf spring, torsion spring, or air damper can be used as the elastic member.

In the first embodiment described above, the control unit 30 is provided with the main power supply 30a. However, this is not limiting, and the control unit 30 and the main power supply 30a may be provided separately.
In the first embodiment described above, the case where the longitudinal axis direction of the cam portion 22 is aligned with the Z direction when the brake device 5 is not driven has been described. However, this is not limited to this, and it is sufficient that the longitudinal axis direction of the cam portion 22 when the brake device 5 is not driven is aligned with the radial direction of the disc portion 3.

In the first embodiment described above, a cam receiving groove portion 12 is formed on the first surface 3a of the disc portion 3, and the outer peripheral surface 22d of the cam portion 22 is pressed against each of the two inner surfaces 12b, 12c formed thereby. However, this is not limited to this, and it is sufficient that the outer peripheral surface 22d of the cam portion 22 is pressed against at least one of the two inner surfaces 12b, 12c. In this case, the angle of the cam portion 22 as viewed from the Y direction when the brake device 5 is activated may be set as follows:

6A and 6B are explanatory diagrams showing the behavior of the cam portion 22 in a modified example of the first embodiment, and correspond to the above-mentioned FIG.
6, when the brake device 5 is not driven, the longitudinal axis direction of the cam portion 22 as viewed from the Y direction may be slightly inclined rather than parallel to the Z direction. It is desirable to determine this inclination direction based on the predicted direction of rotation of the disc portion 3 when it is stopped.
The predicted rotation direction is, for example, the predicted rotation direction of the disk unit 3 due to the effect of the weight of the tilt arm 6, etc., if a malfunction occurs in the main power supply 30a or the like when the disk unit 3 is stopped and the electromagnetic brake of the disk drive device 4 stops operating. This predicted rotation direction is determined by the position of the tilt arm 6 when the disk unit 3 is stopped.

For example, the predicted rotation direction of the disc portion 3 is assumed to be the clockwise direction in Figure 6 (the direction of the arrow CW in Figure 6). Furthermore, when the brake device 5 is activated, the outer peripheral surface 22d of the cam portion 22 is pressed only against the first inner surface 12b of the cam receiving groove portion 12. In such a case, the cam portion 22 is arranged so that the upper outer peripheral surface 22d of the cam portion 22 contacts the first inner surface 12b while tilted toward the upstream side of the predicted rotation direction of the disc portion 3.

With this configuration, when the disc portion 3 attempts to rotate in the predicted rotation direction, the cam portion 22 also attempts to rotate (see arrow Y2 in FIG. 6 ). This causes the outer peripheral surface 22d of the cam portion 22 to be further pressed against the first inner surface 12b, reliably generating a braking force on the disc portion 3. Therefore, a large braking force can be obtained by the brake device 5 without increasing the size of the coil spring 52.
In such a case, it is desirable to provide two types of brake devices 5 in which the inclination direction of the cam portion 22 differs depending on the predicted direction of rotation.

Second Embodiment
<Drive unit>
Next, a second embodiment of the present invention will be described with reference to FIG. 1 and based on FIG.
7 is a block diagram showing a driving device 201 according to the second embodiment. The same components as those in the first embodiment are denoted by the same reference numerals and will not be described further.
As shown in FIGS. 1 and 7 , in the second embodiment, a drive device 201 includes a support portion 2, a disk portion 3, a disk drive device 4, a brake device 205, a tilt arm 6, and a rotary table 7. The disk portion 3 is rotatably supported by the support portion 2. The disk drive device 4 drives the disk portion 3 to rotate. The brake device 205 applies a braking force to the disk portion 3. The tilt arm 6 is provided on the disk portion 3. The rotary table 7 is provided on the tilt arm 6. The basic configuration of this second embodiment is the same as that of the first embodiment described above.

The difference between the first and second embodiments is that the brake device 5 of the first embodiment is equipped with an actuation unit 28, whereas the brake device 205 of the first embodiment does not have an actuation unit 28. Instead, the drive device 201 of the second embodiment is equipped with a secondary power supply 30b that supplies power to the brake device 205. The drive device 201 of the second embodiment also has a detection unit 60 that detects the energization state of the main power supply 30a that supplies power to the disk drive device 4 and a failure of the disk drive device 4. The power supply and drive control to the brake device 5 from the secondary power supply 30b, and the input and output of signals from the detection unit 60 are performed by the control unit 30.

<Operation of Brake Device and Drive Device>
Next, we will explain the operations of the brake device 205 and the drive device 201. In the following explanation, the operations of the disk drive device 4, the brake device 205, and the turntable 7 itself are the same as those in the first embodiment, so explanations will be omitted.
The brake device 205 is driven based on a drive signal from the control unit 30, and applies a braking force to the disk unit 3. When the drive device 1 is driven, the control unit 30 releases the brake and drives the drive device main body 14 of the disk drive device 4. This causes the disk unit 3 to rotate around the disk rotation axis C1.

Here, when the detection unit 60 detects an abnormality in the main power supply 30a that supplies power to the disk drive device 4 or a failure in the disk drive device 4, the control unit 30 activates the brake device 205. This applies a braking force to the disk unit 3, preventing it from rotating unintentionally.
Therefore, according to the second embodiment, the same effects as those of the first embodiment can be achieved.

In the second embodiment described above, the detection unit 60 detects the energization state of the main power supply 30a that supplies power to the disk drive device 4 and a failure of the disk drive device 4. However, this is not limited to this, and the detection unit 60 only needs to detect at least one of the energization state of the main power supply 30a and a failure of the disk drive device 4.

The present invention is not limited to the above-described embodiment, and includes various modifications to the above-described embodiment without departing from the spirit of the present invention.
For example, in the above-described embodiment, the brake device 5 is used in the drive device 1, 201 having the disk portion 3 as a rotating body. However, the present invention is not limited to this, and the configuration of the brake device 5 can be used as a configuration for applying a braking force to various rotating bodies.

In the above-described embodiment, an electric motor unit 16 is provided in the disk drive device 4, and the disk drive device 4 is driven by this electric motor unit 16. Also, an electric motor unit 23 is provided in the brake device 5, and the brake device 5 is driven by this electric motor unit 23. Furthermore, an electric motor unit (not shown) is provided in the rotary table 7, and the rotary table 7 is driven by this electric motor unit. However, this is not limited to this, and any device that can provide power to the disk drive device 4, brake device 5, and rotary table 7 may be used. For example, a hydraulic motor unit or the like may be used in place of the electric motor unit 16, electric motor unit 23, etc.

In the above-described embodiment, the reduction gear unit 24 of the cam drive unit 21 uses the carrier 32 as the output unit, and the cam unit 22 is driven to rotate by the output of this carrier 32. However, this is not limited to this, and it is also possible for the case 31 to be the output unit. In this case, the carrier 32 is fixed to the bracket 20, and the cam unit 22 is fixed to the case 31. A similar configuration can also be adopted in the drive unit main body 14 of the disk drive unit 4.

In the above-described embodiment, a case where a friction material 50 is provided on the cam portion 22 has been described. However, this is not limited to this, and the cam portion 22 does not necessarily have to be provided with a friction material 50. Furthermore, instead of the friction material 50, the outer peripheral surface 22d of the cam portion 22 may be formed with a rough surface roughness. In the above-described embodiment, a case where the cam receiving groove portion 12 is formed in an annular shape centered on the disc rotation axis C1 has been described. However, this is not limited to this, and the cam receiving groove portion 12 does not necessarily have to be formed in an annular shape. For example, if the disc portion 3 rotates within a certain range of rotation angles, it is sufficient that the cam receiving groove portion 12 is formed in an arc shape within this range.

In the above embodiment, two inner surfaces 12b, 12c are formed by forming a cam receiving groove 12 on the first surface 3a of the disc portion 3. These inner surfaces 12b, 12c are used as brake surfaces against which the cam portion 22 is pressed. However, this is not limited to this. A wall surface protruding along the disc rotation axis C1 may be provided on the first surface 3a of the disc portion 3, and this wall surface may be used as the brake surface.

In the above embodiment, the inner surfaces 12b, 12c of the cam receiving groove portion 12 are circular brake surfaces with their surface direction aligned with the disc rotation axis C1 and centered on the disc rotation axis C1. The cam portion 22 generates a braking force by contacting the inner surfaces 12b, 12c, which form the brake surfaces. However, this is not limited to this, and a cam receiving portion against which the cam portion 22 is pressed may be provided on the first surface 3a of the disc portion 3. The pressing force of the cam portion 22 against the cam receiving portion may be applied along the disc rotation axis C1. A portion of the first surface 3a of the disc portion 3 may also be used as the cam receiving portion.

In the above embodiment, the rotation axis of the cam portion 22 (brake device rotation axis C4) is parallel to the disc rotation axis C1 and the drive device rotation axis C3. However, this is not limited to this, and the brake device rotation axis C4 may be aligned with the disc rotation axis C1 and the drive device rotation axis C3. Furthermore, the brake device rotation axis C4 may intersect with the disc rotation axis C1 and the drive device rotation axis C3. It is sufficient that the cam portion 22 can be rotated to press against the cam receiving groove portion 12 (cam receiving portion).

In the above embodiment, the reduction unit 24 is described as a so-called eccentric oscillation type reduction unit. However, this is not limited to this, and in addition to the reduction unit 24, other reduction units (such as reduction unit 17) may be configured to reduce the input rotation speed at a constant rate and output the reduced speed. This is not limited to an eccentric oscillation type reduction unit. Furthermore, a reduction unit need not be provided.

In the above-described embodiment, an eccentric oscillating type speed reducer is used. In this case, the speed reducer 24 includes a cylindrical case 31, an output section (carrier 32) disposed radially inside the case 31, and a mechanism 33 that rotates the carrier 32 at a rotation speed that is reduced by a fixed ratio relative to the rotation speed of the motor shaft 23a. Furthermore, in this case, the mechanism 33 includes three transmission gears 42 that mesh with the external teeth 23b of the motor shaft 23a, three crankshafts 43 whose ends are fixed to the transmission gears 42 and rotatably supported on the end plate 39 and base plate 38, and a first external gear 44 and a second external gear 45 that oscillate and rotate in conjunction with the rotation of the crankshafts 43. However, this is not limited to this, and for example, a single crankshaft 43 may be used.

For example, we will explain in more detail an eccentric oscillating type reduction unit having one crankshaft. In this case, the reduction unit has a so-called center crankshaft that is coaxial with the brake device rotation axis C4 as the crankshaft. As this center crankshaft rotates, the first external gear 44 and the second external gear 45 oscillate and rotate.

Among the embodiments disclosed in this specification, those that are comprised of multiple objects may be integrated, and conversely, those that are comprised of a single object may be separated into multiple objects. Regardless of whether they are integrated, it is sufficient that they are configured in a way that allows the purpose of the invention to be achieved.

1, 201... Drive device 3... Disk unit (rotating body)
3a…First page (one page)
4...Disk drive device (rotating body drive device)
5, 205... Brake device 12... Cam receiving groove portion (cam receiving portion)
12b...first inner surface (braking surface, inner surface)
12c...Second inner surface (braking surface, inner surface)
21... Cam drive unit 22... Cam unit 23... Electric motor unit 28... Urging unit 30... Control unit 30a... Main power supply 30b... Subsidiary power supply 35... Drive side pressing plate 51... Cam side pressing plate 52... Coil spring (elastic member)
60...Detection portion C1...Disc rotation axis (rotation axis of the rotating body)
C4...Brake device rotation axis (cam rotation axis)

Claims (15)

a cam receiving portion provided on one surface of the rotating body, the normal direction of which is the rotation axis direction;
a cam portion that comes into contact with and separates from the cam receiving portion;
a cam drive unit having a brake device rotation axis that coincides with the rotation center of the cam unit and that rotationally drives the cam unit;
Equipped with
The cam portion comes into contact with and separates from the cam receiving portion as the cam portion rotates.
Brake device. the cam receiving portion has a brake surface whose surface direction is along the rotation axis,
The cam portion comes into contact with and separates from the braking surface as it rotates.
The braking device according to claim 1. The braking surface is formed in a circular shape centered on the rotation axis.
The braking device according to claim 2. the cam portion has an elliptical shape having a major axis and a minor axis perpendicular to a rotation axis of the cam portion,
the cam receiving portion has the brake surfaces provided on the radially outer side and the radially inner side of the rotating body with the cam portion interposed therebetween;
The braking device according to claim 2. the cam receiving portion is a groove portion formed on the one surface of the rotating body,
The inner surface of the groove portion is the braking surface.
A brake device according to any one of claims 2 to 4. The cam drive unit has an electric motor unit.
The braking device according to claim 1. The rotation axis of the cam portion is aligned with the rotation axis direction of the rotating body.
The braking device according to claim 1. a biasing portion that biases the cam receiving portion in a direction that brings the cam portion into contact with the cam receiving portion;
The braking device according to claim 1. The biasing portion is
a cam side pressing plate provided on the cam portion;
a drive side pressing plate provided in the cam drive portion;
an elastic member provided between the cam side pressing plate and the drive side pressing plate, the elastic member biasing the cam side pressing plate in a direction around the rotation axis;
Equipped with
9. The braking device according to claim 8. the cam driving portion rotates the cam portion against the biasing force of the biasing portion so that the cam portion does not contact the cam receiving portion.
The brake device according to claim 8 or 9. a cam receiving portion provided on one surface of a rotor that rotates around a first rotation axis and whose normal direction is the first rotation axis direction;
a cam portion that rotates about a second rotation axis along the first rotation axis direction and that comes into contact with and separates from the cam receiving portion;
a cam drive unit having a brake device rotation axis that coincides with the rotation center of the cam unit and having an electric motor unit for rotationally driving the cam unit;
Equipped with
the cam receiving portion has a brake surface whose surface direction is along the first rotation axis and which is formed concentrically with the first rotation axis,
the cam portion has an elliptical shape having a major axis and a minor axis perpendicular to the second rotation axis, and contacts and separates from the braking surface as the cam portion rotates.
Brake device. a cam receiving portion provided on one surface of a rotor that rotates around a first rotation axis, the surface being normal to the first rotation axis, the cam receiving portion having a brake surface that is formed concentrically with the first rotation axis and whose surface direction is along the first rotation axis;
a cam portion that rotates about a second rotation axis along the first rotation axis direction and that comes into contact with and separates from the cam receiving portion;
a cam driving unit having an electric motor unit for driving the cam unit to rotate;
a biasing portion that biases the cam portion in a direction that brings the brake surface into contact with the cam portion;
Equipped with
The biasing portion is
a cam side pressing plate provided on the cam portion;
a drive side pressing plate provided in the cam drive portion;
an elastic member provided between the cam side pressing plate and the drive side pressing plate, the elastic member biasing the cam side pressing plate in a direction around the second rotation axis;
Equipped with
the cam drive portion rotates the cam portion against the biasing force of the biasing portion so that the cam portion does not contact the brake surface.
Brake device. a rotating body that rotates about a first rotation axis;
a rotating body driving device that rotationally drives the rotating body;
a braking device that applies a braking force to the rotating body;
Equipped with
The braking device is
a cam receiving portion provided on one surface of a rotor that rotates around a first rotation axis and whose normal direction is the first rotation axis direction;
a cam portion that rotates about a second rotation axis along the first rotation axis direction and that comes into contact with and separates from the cam receiving portion;
a cam drive unit having a brake device rotation axis that coincides with the rotation center of the cam unit and that rotationally drives the cam unit;
Equipped with
the cam receiving portion has a surface direction aligned along the first rotation axis and is formed concentrically with the first rotation axis, and has a brake surface disposed radially outward of the rotor drive device,
The cam portion comes into contact with and separates from the braking surface as it rotates.
Drive unit. a biasing portion that biases the cam portion in a direction that brings the brake surface into contact with the cam portion;
a main power source that supplies power to the rotary body drive device and the cam drive unit;
Equipped with
The biasing portion is
a cam side pressing plate provided on the cam portion;
a drive side pressing plate provided in the cam drive portion;
an elastic member provided between the cam side pressing plate and the drive side pressing plate, the elastic member biasing the cam side pressing plate in a direction around the second rotation axis;
Equipped with
14. The drive device according to claim 13. a detection unit that detects a power supply state of a main power source that supplies power to the rotary body drive device or a failure of the rotary body drive device;
a secondary power supply that supplies power to the cam drive unit;
a control unit that controls the drive of the cam drive unit based on the detection result of the detection unit;
Equipped with
14. The drive device according to claim 13.