JPS63167150A - Speed change gear for control - Google Patents

Abstract

PURPOSE:To eliminate a backlash, by supporting rods of arm shafts of planetary gears in fitting holes of a carrier and adjusting a half of arm shafts to rotate clockwise and the rest half of arm shafts to rotate anti-clockwise under the state of a stopped sun gear. CONSTITUTION:A sun gear 5, an internal teeth gear 7 and planetary gears 8a-8d are assembled. When arms shaft 9a-9d with eccentric rods 10 are rotated, a set of planetary gears 8a, 8b are rotated in the direction F and the rest of planetary gears 8c, 8d are rotated in the direction G. A backlash is eliminated by rotating these gears until contact points with the teeth surfaces of the sun gear 5 and contact points with the teeth surfaces of the internal gear 7 reach respective set positions.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a transmission device used in a control device such as an industrial robot whose rotational direction is switched between forward and reverse during operation.

[Prior art]

In control equipment such as industrial robots, the direction of rotation is not limited to one direction, but is operated by switching between forward and reverse directions at any time. On the other hand, there is always backlash in the gears of transmissions installed in such control equipment, and due to this backlash, each time the direction of rotation is switched between forward and reverse, the amount of rotation is delayed by the amount of backlash, resulting in failure of transmission. The problem of accuracy has been pointed out.

Conventionally, in order to eliminate such transmission inaccuracies due to buff crash, a mechanism has been proposed in which gears are stacked double, the phase is shifted by the amount of backlash, and the two tooth surfaces mesh with each other with zero backlash. has been done. However, since errors inevitably occur in backlash due to the manufacturing process,
It is extremely difficult to fix two gears to the shaft with their phases shifted by the amount of backlash, which has such a minute error, from the viewpoint of indexing accuracy in machining. Also,
Since it is a two-tooth mesh, the inevitable rusting effect that will occur in the future is unavoidable, making smooth operation difficult.

The inventor of the present invention previously proposed a transmission that solves the above-mentioned problems in Japanese Patent Application No. 61-67876 and Japanese Patent Application No. 61-155.
No. 194, etc., proposed an effective invention that uses a star gear mechanism or a planetary gear mechanism to eliminate backlash.

This proposal uses a star gear mechanism,
While the spindle of a planetary gear (planetary gear) is fixed to the outer casing, in a transmission using a planetary gear mechanism,
The support shaft of the planetary gear is eccentrically supported by the carrier.

Therefore, when erasing backlash, it is necessary to adjust the spindle to the carrier inside the casing while the sun gear, planetary gear, and internal gear are assembled, which is a very labor-intensive operation. The problem was that it became a hassle.

[Purpose of the invention]

An object of the present invention is to provide a control n that can easily realize the adjustment operation in a structure that uses a planetary gear mechanism previously proposed by the present inventor to bring backlash to a substantially O state. The purpose of this invention is to provide a transmission for use in automobiles.

[Structure of the invention]

A control transmission of the present invention that achieves the above object is a planetary gear in which an even number of planetary gears supported by a carrier are interposed between a rotatably supported sun gear and a fixed internal gear. In the mechanism, a rod is integrally connected to the support shaft of the planetary gear in an eccentric state, and this rod is supported in a fitting hole of the carrier. The shafts can be adjusted to move clockwise and counterclockwise substantially along the same direction, and half of the shafts can be rotated clockwise and the other half can be rotated counterclockwise while the sun gear stops rotating. The rod has a configuration in which gear backlash is eliminated by dynamic adjustment, and the rod fitting hole is separated into a split hole provided on the carrier side and a split hole provided on the pressing member side independent of the carrier. The present invention is characterized in that a single pressing member holds two sets of split holes, each with a rod between them, and is tightened and fixed with a bolt inserted at an intermediate position between the two sets of split holes.

〔Example〕

1 to 4 show an example of a control transmission of the present invention using a planetary gear mechanism having an even number of four planetary gears.

In these figures, 1 is a high-speed shaft, 2 is a low-speed shaft, and 3 is a casing. In this embodiment, the casing 3 is constructed so that the internal gear 7 is sandwiched between a bracket 3a on the high-speed shaft side and a bracket 3b on the low-speed shaft side. High speed axis 1 is
It is rotatably supported by a bearing portion 4 of a bracket 3a, and has a sun gear 5 fixed to its inner end. On the other hand, the low-speed shaft 2 is rotatably supported by the other bearing portion 6 of the bracket l-3b. Between the sun gear 5 and the internal gear 7, an even number (four in this embodiment) of planetary gears 8a are distributed at equal intervals.
, 8b, 8c.

8d is engaged. In this embodiment, a sun gear 5, an internal gear 7. The planetary gears 8a, 8b, 8c, and 8d are all spur gears.

The planetary gears 8a, 8b, 8c, and 8d are floating with respect to the support shafts 9a, 9b, 9c, and 9d, respectively. ...
, 13, and is also supported during migration through 13.
-..., 13 are rotatably supported on support shafts 9a, 9b, 9c, and 9d via bearings. This floating intermediate shaft 13. -・-113 and planetary gears 8a, 8b, 8c, 8
A gap 14 in which an oil film can be formed is formed between the gap 14 and d. In the figure, the clearance 14 is exaggerated and shown to be large in order to explain the effect described later, but in reality, it is an extremely small clearance that is optimal for the generation of an oil film.

The above-mentioned support shafts 9a, 9b, 9c, and 9d have screws 11 at their ends.
are provided, and the planetary gears 8a, ab are connected by a nut 12 screwed onto the screw 11.

This is to prevent 8c and 8d from popping out. Moreover, at the other end, a rod 10. which is eccentric by a distance e.・
-., 10 are integrally connected, and a fitting hole 17. is provided in the carrier 16. ...-117 is inserted and supported.

The fitting hole 17 is a dividing hole 17a provided at the edge of the carrier 16.
and a dividing hole 17b provided in a pressing member 18 independent of the carrier 16. In this case, in this embodiment, the dividing hole 17a on the carrier 16 side has an arc of 1/2 or more of the circumference, whereas the dividing hole 17a on the pressing member 18 side has an arc of 1/2 or more of the circumference.
b is set to be an arc of 1/2 or less.

Two sets of fitting holes 17 constituted by two sets of split holes 17a and 17b are provided per one pressing member 18, and with the rod 1o being held in each pair, the two fitting holes 17 are
It is tightened and fixed to the carrier 16 by a bolt 20 with a cap nut inserted into the intermediate position of the pair of fitting holes 17 and 17. Therefore, the rod 1o is rotatable when the bolt 20 is loosened, and is attached to the support shaft 9a.

The relative rotational positions of 9b, 9'c, and 9d can be adjusted, and when the bolt 20 is tightened, they are fixed at that position.

Now, in the configuration of the planetary gear mechanism described above, the support shafts 9a and 9b are provided with the eccentric rod 10.

By adjusting the rotation of 9c and 9d, it is possible to set the gears in a state in which backlash is eliminated as follows.

That is, the sun gear 5, internal gear 7, planetary gear 8a,
8b, 8c, and 8d are assembled, the bolts 20 are left in a loosened state, and the casing 3 is left in a state in which only the bracket 3a on the high-speed shaft side is removed. From this state, the high-speed shaft 1 and the low-speed shaft 2 are locked in a non-rotating state, and then, as shown in FIG. The remaining two support shafts 9c and 9d, which are also in a diagonal relationship, are rotated in the direction of arrow G, which is opposite to the direction of arrow F, until they come to a stop, using the rod 10 as a fulcrum.

By such rotational operation of the support shafts 9a, 9b, 9c, and 9d, the planetary gears 8a, 8b, 8c, and 8d are also rotated by the rod 10. ..., 10, but the amount of rotation is small enough to eliminate the backlash, so in the circumferential direction around the axis of the sun gear 5, it rotates along Pa. can be considered. Therefore, the planetary gears 3a, 3b and 3c, 8d are respectively the former 8a.
, 8b in the F direction, and the latter 13c.

8d rotates in the G direction, when the contact with the tooth surface of the sun gear 5 and the contact with the tooth surface of the internal gear 7 are in the state shown in FIG. 2, that is, when the backlash has disappeared. Stop.

When the rotation stops in this way, the gear train consisting of the planetary gears 8a and 8b rotated in the F direction, that is, the planetary gear 8a
, 8b and sun gear 5. The gear train is in contact with the internal gear 7 in the direction in which the sun gear 5 rotates in the counterclockwise direction R. In addition, a gear train consisting of the other planetary gears 8c and 8d, that is, the planetary gears 8c and 8d and the sun gear 5
．． The gear train is in contact with the internal gear 7 in the direction in which the sun gear 5 rotates in the clockwise direction C.

When such a state of tooth contact is achieved, a rotary operating tool such as a spanner is inserted through the opening 21 provided in the bracket 3b, and the bolt 20 is tightened. At this time, by tightening one bolt 20 for each pressing member 1o, the pressing member 18 is pressed toward the carrier 16, and the
The book rod 10.10 is fixed at the same time. The above-mentioned backlash elimination can be performed by an extremely simple operation such as just tightening the bolts.

After setting such backlash elimination, the high-speed shaft 1 and the low-speed shaft 2 may be unlocked, the bracket 3a may be attached, and the opening 21 may be closed if necessary. In this way, according to the planetary gear mechanism having the above structure, it is possible to easily realize the bala crash erasing operation.

Now, in the transmission set in the tooth contact state shown in FIG. However, the deceleration is transmitted to the low-speed shaft 2 via the gear train of the other planetary gear 8a and the planetary gear 8b. In other words, when rotating in the clockwise direction C, the teeth of both gear trains are in contact with each other by the other planetary gears 8a and 3b, with a gap C interposed in the rotation direction, and power is not transmitted, but in the opposite direction. It simply follows the rotation while keeping the side tooth surfaces in contact.

On the other hand, when the high-speed shaft 1 is in the counterclockwise direction R (reverse direction), the power is transferred to the other planetary gear 8a, contrary to the above-mentioned normal rotation.
The deceleration is transmitted to the low speed shaft 2 through the gear train of the example gear and the planetary gear 8b, and is not transmitted to the low speed shaft 2 through the gear train of the planetary gears 8c and 8d. That is, the tooth contact state between the gear train of the planetary gear 8c and the gear train of the planetary gear 8d at the time of this reverse rotation R is a state in which a gap C' is interposed in the rotation direction, and the tooth surface on the opposite side is in contact with the gear train of the planetary gear 8c. It simply follows and rotates while keeping in contact.

In this way, the gear train on the side that does not transmit power follows the rotation while maintaining the contact state, so when switching from the forward direction C to the reverse direction R, or from the reverse direction R to the forward direction C, the moment of the change Then, the gear train side that was following in the above-mentioned contact state immediately performs a power transmission action, and the rotation direction is effectively switched in a state of baraclash O. Therefore, accurate transmission can be performed without causing a rotational delay by the amount of the baraclash.

Moreover, in the transmission described above, the planetary gear 3a.

8b, 8c, and 8d are clearances 1 that generate oil films, respectively.
4, the floating gap 14 is rotatably supported by the width 13 of the floating gap 14, so that fluctuations in the eccentric angle due to the oil film in the clearance 14 and fluctuations in the radial direction of the sun gear 5 are allowed, making it easy to manufacture gears. It absorbs various errors in the gear train and equally distributes power to multiple gear trains, enabling extremely smooth operation.

In the above-described embodiment, the case of a speed reduction device was illustrated, but if the low speed shaft is set as the input side and the output is output to the high speed shaft side, application as a speed increase device becomes possible.

〔Effect of the invention〕

As described above, according to the control transmission of the present invention, when half of the planetary gears in the planetary gear mechanism are used as the power transmission side, the gear train of the remaining half of the planetary gears is simply brought into contact with the tooth surfaces. Since only tracking can be performed, when switching the rotation direction between forward and reverse, the meshing relationship of the gears can be immediately switched to a state in which the backlash is substantially zero.

Therefore, accurate transmission without rotational delay is possible.

Furthermore, in such a mechanism, the planetary gear is supported by an eccentric rod on the carrier, and the fitting hole of the eccentric rod is configured to be separated into a split hole on the carrier side and a split hole on the pressing member side, so that the planetary gear can be separated into one. The rod can be easily fixed because two sets of split holes are provided in the pressing member and the rod is tightened and fixed with a bolt inserted at an intermediate position. Therefore, the erasing and assembly work with zero backlash can be performed with extremely simple operations.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a transmission according to an embodiment of the present invention, FIG. 2 is a principle diagram illustrating the operation of the transmission when FIG. 1 is viewed from the nn arrow direction, and FIG. A cross-sectional view of Fig. 1 when viewed from the mm-m arrow direction, Fig. 4 is a cross-sectional view taken along IV-IV of Fig. 3.
It is a sectional view taken in the direction of arrows. DESCRIPTION OF SYMBOLS 1... High-speed shaft, 2... Low-speed shaft, 3... Casing, 3a, 3b... Bracket, 5... Sun gear, 7... Internal gear, 8a, 8b, 8c, 8d.
・・Planetary gear, 9a, 9b, 9c, 9d-support shaft, 10
...Rod, 16...Carrier, 17...
・Fitting holes, 17a, 17b...dividing holes, 18...
- Pressing member, 20... bolt.

Claims (1)

[Claims] In a planetary gear mechanism in which an even number of planetary gears supported by a carrier are interposed between a rotatably supported sun gear and a fixed internal gear, a rod is eccentrically attached to the support shaft of the planetary gear. By integrally connecting the rods and supporting the rods in the fitting holes of the carrier, the planetary gears are aligned substantially along the circumferential direction around the axis of the sun gear together with the support shaft in the clockwise and counterclockwise directions. The gears are configured so that they can each be adjusted freely, and when the sun gear stops rotating, half of the spindles are adjusted clockwise and the other half are rotated counterclockwise to eliminate the backlash of the gears. and a split hole in which the rod fitting hole is provided on the carrier side;
The carrier is separated from the split holes provided on the side of the pressing member, which is independent of the carrier, and the two sets of split holes are inserted into the intermediate position between the two sets of split holes with the rod sandwiched between the two sets of the single pressing member. A control transmission characterized by being tightened and fixed with bolts.