JPH0379257A - Index device - Google Patents

Abstract

PURPOSE:To miniaturize a speed reducer itself and to miniaturize the whole device, by composing a speed reducer with an external gear, a crank shaft and the internal gear having slightly larger number of teeth than those of the external gear and providing a table on the internal gear. CONSTITUTION:A crank shaft 22 is rotated with the rotational of an output shaft 28 and an external gear is eccentrically rotated without self-revolving by the eccentric cam 23 fitted to the external gear 19. Owing to the internal gear 31 having slightly more teeth than those of the external gear 19 being bitten with its whole teeth to the external gear 19, the rotation of the output shaft 22 is transmitted to the internal gear 31 with its speed reduction at a high radio. Since a table main body 36 is fitted to the internal gear 31, the table main body 36 is indexed with the rotation of the internal gear 31 in the specific quantity and stopped by a clamp means 59. Also the reaction force based on the power transmission is supported enough by a reinforced column 10 of high torsional rigidity. The structure of the device whole body can thus be simplified and miniaturized.

Description

[Detailed description of the invention] ■ The present invention relates to an indexing device.

[End 2] Conventionally, indexing devices that rotate and index a table on which a work is placed to a predetermined rotational position have been used, for example, between a rotating table, a stationary base, and a table and a base. A gear reduction gear is known that includes a gear reduction gear using a worm, a worm wheel, etc., and a motor that applies rotational force to the gear reduction gear.

However, since all of these indexing devices have large gear reducers, the entire device becomes large, and this increase in size becomes particularly noticeable when the reduction ratio is increased. .

An object of the present invention is to provide an indexing device that can be downsized as a whole even when the reduction ratio is increased.

The purpose of this kit is to have a stationary base, a plurality of reinforcing columns connected to the base and extending perpendicularly to the base, and end plates fixed to these reinforcing columns so as to connect the ends of these reinforcing columns. an external gear provided between the base and the end plate and having a plurality of holes into which the reinforcing columns are loosely fitted; and at least one external gear that is inserted into the external gear and rotated to eccentrically rotate the external gear. A table that has a main crankshaft, a motor that rotates the crankshaft, and an internal gear that meshes with the external gear that has a slightly larger number of teeth than the external gear, and that rotates by decelerating the eccentric rotation of the external gear at a high ratio. This can be achieved by having the following.

When performing indexing using the indexing device of the present invention, the motor is operated to rotate the crankshaft, thereby eccentrically rotating the external gear. At this time, the internal gear of the table meshes with the external gear with all its teeth, but since the number of teeth of this internal gear is slightly greater than the number of teeth of the external gear, the eccentric rotation of the external gear is reduced by a high ratio. and communicated. The table rotates in this manner, but when the table rotates by a predetermined angle and indexing is completed, the rotation stops. Here, in this invention, the above-mentioned external gear, crankshaft,
The reduction gear is composed of internal gears.

Moreover, since the internal gear is provided on the table, the reducer itself is small and has a simple structure, and the entire device can be downsized. Furthermore, since the reaction force based on power transmission between the external gear and the internal gear is supported by a reinforced column with high torsional rigidity whose tips are connected by an end plate, the part that supports the reaction force can be There is no need to increase the rigidity by increasing the thickness, and as a result, the entire device can be made simpler and smaller in size.

Furthermore, with the configuration as set forth in claim 2, the table can be clamped while keeping the device compact.

Practical JL Example Hereinafter, a first embodiment of the present invention will be described based on the drawings.

In Fig. 1.2, 1 is a frame of an indexing device 2, on which a stationary base 3 is fixed. This base 3 is composed of a disc body 5 having an inner cylindrical portion 4 and an outer cylindrical body 6 fixed to the radially outer end of this disc body 5. A ring-shaped cylinder chamber 7 is formed between the disc body 5 and the inner cylindrical portion 4 . The base 3 is connected to a main body 11 having a plurality of reinforcing columns 10, in this case three reinforcing columns 10, extending perpendicularly to the base 3, and the upper ends of these reinforcing columns 10 are connected to the ends fixed to these reinforcing columns 10. They are connected to each other by a plate 12. Between the base 3 and the end plate 12 are a plurality of holes 1, in this case three holes 1, into which reinforcing columns 10 are loosely fitted.
Two external gears 18 having a number 8 formed thereon are arranged, and a large number of external teeth 20 are formed on the outer periphery of these external gears 18. Reference numeral 22 has two eccentric cams 23 in the center, and at least one crankshaft, in this case, three crankshafts, which are arranged alternately in the circumferential direction with the reinforcing column lO, and these crankshafts 2
Both ends of the bearing 2 are attached to the end plate 12 and the main body 11, respectively.
4.25 is supported on the rotating part. and,
These eccentric cams 23 of the crankshaft 22 are inserted into the external gear 19 with needle bearings 26 interposed therebetween. 27 is a motor fixed to the base 3; an external gear 28 is formed at the tip of an output shaft 28 of this motor 27; External gears 30 with a large number of teeth are meshed. As a result, motor 2
7 operates, the crankshaft 22 rotates in response to the driving force transmitted via the external gears 29 and 30. 31 is a cylindrical internal gear that surrounds the reinforcing column 10 and the external gear 19, and this internal gear 31 is rotatably supported by the end plate 12 and the main body 11 via a pair of bearings 32 and 33. . On the inner periphery of this internal gear 31, a large number of internal teeth 34 are formed with all teeth meshing with the external teeth 20 of the external gear 19, and the number of teeth of these internal teeth 34 is one less than the number of teeth of the external teeth 20. As a result, when the crankshaft 22 rotates, the external gear 1
In 9, the external gear 20 is the internal gear 3! It rotates eccentrically while meshing with the inner part 134. In Fig. 2, pins are installed in all the pin grooves, but if you remove multiple pins from such a situation (for example, remove every other bottle and double the installation pitch) Therefore, the number of teeth of the internal gear referred to in the present invention refers to the number of teeth before the bottle is removed as described above. Reference numeral 36 denotes a substantially disk-shaped table body, and this table body 3B is fixed to the internal gear 31. The internal gear 31 mentioned above. The table body 36 as a whole constitutes a table 37, and this table 37 rotates while reducing the eccentric rotation of the external gear 19 by increasing the height.

40 is an annular groove formed on the inner periphery of the outer cylindrical body B facing the table 37, and this annular groove 40 and the cylinder chamber 7 as a whole form a ring-shaped storage space 41 formed in the base 3. Configure. A substantially cylindrical collet 42 is housed in the annular groove 40, and a plurality of bendable claws 44 are formed at the lower end of the collet 42. These claws 44 can be opened and closed by synchronously bending in the radial direction.
An inclined surface 45 is formed on the outer periphery of the tip 4. The inclined surface 45 approaches the inner side in the radial direction as it goes downward, that is, tapers toward the tip. On the other hand, a substantially cylindrical piston 51 is housed in the cylinder chamber 7, and this piston 51
divides the cylinder chamber 7 into a first chamber 52 and a second chamber 53. Reference numerals 54 and 55 denote first and second passages formed in the outer cylindrical body 6 and the disc body 5, respectively;
, one end of the second passage 54.55 is connected to the first and second chambers 52.53.
The other end is connected to a fluid source via a switching valve (not shown). The piston 51 has an inclined surface 58 on the inner periphery of the upper end protruding from the cylinder chamber 7, which is inclined in the same direction and at the same angle as the inclined surface 45, and this inclined surface 58 is in surface contact with the inclined surface 45 of the collet 42. ing. Then, the second chamber 53 is passed through the second passage 55.
When fluid is supplied to the collet 42, the piston 51 closes the claw 44 of the collet 42 by imitation, presses it against the table 37, and clamps the table 37 to the base 3 with an external grip.

The aforementioned collet 42 and piston 51 as a whole constitute a clamping means 58 housed in the housing space 41.

Next, the operation of the first embodiment of the present invention will be explained.

Assume that the motor 27 is now operating and its output shaft 28 is rotating. This rotation of the output shaft 28 causes the crankshaft 22 to
However, since the eccentric cams 23 of the crankshaft 22 are fitted to the external gear 19, the external gear 19 does not rotate due to the rotation of the crankshaft 22, but only performs eccentric rotation (revolution). , an internal gear 31 meshes with the external gear 19 with gold teeth, but since the number of internal teeth 34 of this internal gear 31 is slightly greater than the number of external teeth 20 of the external gear 13, the internal gear 31 has a motor. The rotation of 27 is decelerated by the height and transmitted. In this manner, the table body 38 rotates by a predetermined amount in response to the rotation of the internal gear 31, and when indexing is completed, the rotation of the table 37 is stopped. Here, in this embodiment, the external gear 18, the crankshaft 22, and the internal gear 31 as described above are used.
Since the speed reducer is configured as shown in FIG. 1 and the internal gear 31 is provided on the table 37, the speed reducer itself is small and has a simple structure, and the entire device can be downsized. Furthermore, the reaction force based on the power transmission from the external gear 18 to the internal gear 31 is
The reaction force is transmitted to the end plate 12 and the reinforcing column 10 via the crankshaft 22, but since the reinforcing column 10 has high torsional rigidity with its tips connected by the end plate 12, the reaction force can be sufficiently absorbed. As a result, there is no need to increase the rigidity by increasing the thickness of the portion that supports the reaction force, and the entire device can be made simpler and smaller in size.

Next, when such indexing is completed, the table 37 is clamped to the base 3, but in this case, first,
Fluid is supplied to the second chamber 53 through the second passage 55, and the piston 51 is moved in the axial direction so as to approach the collet 42. As a result, the pawl 44 of the collet 42 is synchronously pushed inward in the radial direction and bent due to the imitation of the inclined surface 45 of the pawl 44 and the inclined surface 58 of the piston 51, thereby closing the collet as a whole. When the claws 44 are closed in this way, the inner circumferences of these claws 44 are pressed against the outer circumference of the internal gear 31, and as a result, the table 37 is gripped from the outside by the collet 42 and clamped to the base 3. When releasing the collet 42 from the clamp, fluid is supplied to the first chamber 52 to move the piston 51 away from the collet 42. As a result, the claws 44 of the collet 42 are bent outward in the radial direction due to the elastic restoring force and opened. In this way, the table 37 is released from the clamp of the base 3.

FIG. 3 is a diagram showing a second embodiment of the invention. The main difference between this embodiment and the first embodiment is that, first, a cross roller bearing 61 is interposed between the radially outer end of the table 37 and the inner periphery of the upper end of the base 3; This is because the table 37 is rotatably supported in a stable state. Second.

A magnetic band 65 extending in the circumferential direction having a magnetic pattern formed on the circumferential surface of the table 37 is attached, and the base
3, a magnetic sensor 66 that detects the magnetic field of the magnetic band 65;
Attach these magnetic bands 65. It consists of a magnetic sensor 66. The point is that a rotary encoder B7 for detecting the amount of rotation of the table 37 is provided. Thirdly, a piston 72 having an inclined surface 71 formed on the outer periphery of the upper end and a claw 74 having an inclined surface 73 formed in the storage space 41 formed in the base 3.
These claws 74 are pressed against the inner peripheral surface of the table 37 by a piston 72, and the table 37 is clamped to the base 3 by internal gripping. Fourthly, the motor 78 is built into the base 3 to further reduce the size of the device.Fifthly, the base 3 and the reinforcing column 10 are integrally formed and connected to each other.

In addition, in this invention, a crankshaft is directly connected to the output shaft 28 of the motor 27, and the crankshaft is connected to an external gear! The external gear 19 may be inserted into a through hole formed in the center of the crankshaft 9, and the external gear 19 may be eccentrically rotated by this single crankshaft.

11 Standing 1 As explained above, according to the present invention, even when the reduction ratio is increased, the size of the entire device can be reduced.

[Brief explanation of drawings]

FIG. 1 is a front sectional view showing the first embodiment of the invention, and the second embodiment is a front sectional view showing the first embodiment of the invention.
The figure is a sectional view taken along the line II in FIG. 1, and FIG. 3 is a front sectional view similar to FIG. 1, showing a second embodiment of the invention. 3...Base 12...End plate 19...External gear 27...Motor 37...Table 58...Clamping means

Claims (2)

[Claims] (1) A stationary base, a plurality of reinforcing columns connected to the base and extending perpendicularly to the base, an end plate fixed to these reinforcing columns so as to connect the ends of these reinforcing columns, and a base. an external gear having a plurality of holes provided between the end plate and into which the reinforcing columns are loosely fitted; and at least one crankshaft that eccentrically rotates the external gear by being inserted into the external gear and rotating. and a table that has a motor that rotates the crankshaft, and an internal gear that meshes with the external gear that has a slightly larger number of teeth than the external gear, and that rotates while decelerating the eccentric rotation of the external gear at a high ratio. An indexing device characterized by: (2) The indexing device according to claim 1, wherein a ring-shaped storage space is formed in the base, and a clamp means for clamping the table to the base is stored in the storage space.