JPS6249046A - Transmission gear for control - Google Patents

Abstract

PURPOSE:To decrease a backlash to zero, by a method wherein two intermediate shafts are axially movable in a reverse direction to each other. CONSTITUTION:A gear 8 is secured to the one of input and output shafts 1 and 2 positioned facing each other in a state to coincide the axial direction of the one with that of the other. Two gears 9 and 9', independently secured to two intermediate shafts 10 and 10', are simultaneously geared with the gear 8. Different gears 11 and 11' are secured to the intermediate shafts 10 and 10', respectively, and the gears 11 and 11' are simultaneously geared with a single gear 12 transmitted to the other of the input and output shafts 1 and 2. Regulating screws 16, by which the intermediate shafts are movable in reverse axial direction to each other, are respectively attached to the end parts of the two intermediate shafts 10 and 10'. This constitution enables backlash to be reduced to 0.

Description

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

[Prior art]

Control devices such as industrial robots are not operated by rotating only in one direction, but are usually operated while changing the direction of rotation in forward and reverse directions.

Gears are essential in transmissions for such control equipment, but since these gears always have a baraclash, when switching the rotation direction between forward and reverse, the amount of rotation becomes inaccurate by the amount of this paso crash. It has been pointed out that.

In order to eliminate such inaccuracies in the amount of rotation, it is desirable to perform one accurate precision machining of the gear and at the same time reduce the baraclash to zero. However, if you set the baraclash to 0 in a fiiTl gear, each tooth will mesh on both sides, making it impossible to provide relief through tooth deflection, and even the slightest error cannot be tolerated. It can be said that such a solution is virtually impossible.

[Purpose of the invention]

The purpose of the present invention is to create a state in which the bathocrush is substantially equal to O even if the direction of rotation is switched between forward and reverse during operation by skillfully devising a combination of gears, compared to conventional devices. An object of the present invention is to provide a control transmission that enables accurate transmission of rotation amount.

[Structure of the invention]

The present invention achieves the above object by fixing a gear to one of the input and output shafts facing each other with the same axial direction, and to this gear, two gears each individually fixed to two intermediate shafts are attached to the gear. mesh simultaneously to form one gear train,
Different gears are fixed to each of the intermediate shafts, and these different gears are simultaneously meshed with one gear that transmits variable speed transmission to the other of the input/output shafts to form the other gear train, and both the gear trains One of the two is composed of a helical gear and the other is a spur gear, and adjustment screws are provided at the ends of the intermediate shafts of the two trees to enable axial movement in opposite directions. That is.

〔Example〕

Hereinafter, the present invention will be explained with reference to embodiments shown in the drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a speed reduction device.

1 is an input shaft, 2 is an output shaft, and 3 is a casing. A carrier 6 is rotatably supported by a bearing portion 4 on the input shaft 1 side of the casing 3 via a boss portion 7, and the manpower shaft 1 is rotatably supported by the boss portion 7. On the other hand, the output shaft 2 is rotatably supported by the other bearing portion 5 of the casing 3, and is opposed to the input shaft 1 with the same axial direction.

A gear 8 is fixed to the input shaft 1, and two gears 9, 9' mesh with the gear 8 at the same time. These gears 8,
9.9' constitutes a gear train consisting of helical gears. The above gears 9° and 9° each have two intermediate shafts 10
．． 10' and these two intermediate shafts 10,1
0° is rotatably and slidably supported in the axial direction by a carrier 6 on the input shaft 1 side and a carrier 13 fixed to the output shaft 2 at both ends thereof. Each of the two intermediate shafts 10 and 10' has a separate gear 11.
11'' is fixed, and this gear 11.11' simultaneously meshes with an internal gear 12 fixed inside the casing 3.

The gears 11, 11' and the internal gear 12 constitute a gear train consisting of spur gears.

On the other hand, adjustment screw mechanisms 14 and 14 are provided at the shaft end of the intermediate shaft lO on the carrier 6 side and at the shaft end of the intermediate shaft 10'' on the carrier 13 side, respectively, as shown in detail in FIG. .

As shown in FIG. 2, this adjustment screw mechanism 14 fixes a holding frame 15 on the carrier 6 (13) corresponding to the shaft end of the intermediate shaft 10 (10'), and fixes an adjustment screw 16 to this holding frame 15.
is screwed together with the intermediate shaft 10 (lO") so that the axial direction matches. The tip of this adjustment screw 16 and the intermediate shaft 10
(10゛) There are two thrust bearings 17.
An elastic body 19 made of a rubber material is sandwiched between the elastic bodies 18 and 18, and by screwing the adjustment screw 16, the elastic bodies 1
9 etc., press the intermediate shaft 10 (10°) in the axial direction,
It is now possible to move it.

Of the two thrust bearings mentioned above, the thrust bearing 17 is the third
As shown in the figure, protrusions 17a, 17a are formed on both ends of the outer periphery, and it is held within the holding frame 15, and is movable in the axial direction, but cannot rotate. In addition, a window 20 is provided on the wall surface of the casing 3 in correspondence with the adjustment screw mechanism 14.
is provided, and a removable lid 21 is attached to the window 20. However, when performing the shaft movement operation using the adjustment screw 16, it is sufficient to remove the lid 21 and perform the operation through the window 20.

The adjustment screw mechanism 14 provided at the shaft end of the intermediate shaft 10 and the adjustment screw mechanism 14 provided at the shaft end of the intermediate shaft 10' can be adjusted by threading the respective adjustment screws 16 and 16. 10 and 10' are moved in the axial direction in opposite directions, as shown by arrows A and A' in FIG. At this time, as mentioned above, gear 8 and gear 9
, 9゛ are composed of helical gears, so by performing the above shaft movement operation, the meshing state between gear 8 and gears 9 and 9 is set as shown in Fig. 4. . In other words, if both tooth surfaces of the plurality of teeth constituting the gear 8 are the tooth surface on the same side with respect to the rotation direction as a, and the tooth surface on the opposite side as a, then the gear 9 has the same tooth surface as the tooth surface a of the gear 8. In contrast, the gear 9° contacts the tooth surface a'' of the gear 8, and a relationship is established in which the gear 9 contacts the tooth surfaces a'' on opposite sides at the same time.

Therefore, in the above-described reduction gear, when the input shaft 1 rotates normally in the direction of the arrow F, the gear 8 drives the gear 9, but does not drive the gear 9', but simply rotates the tooth surface a'. Follows rotation while remaining in contact. Also, the input shaft 1 is
When the direction is switched and reversed, the gear 8 is in contact with the tooth surface a of the tooth @9, so at the moment of the reversal, the gear 8 immediately starts driving the gear 9. The rotational direction changeover takes place with the eight crushes effectively equal to zero. Therefore, unlike conventional devices, the amount of rotation does not become inaccurate by the amount of bathocrash.

In addition, fine adjustment by bringing the tooth surfaces into contact with each other using the adjustment screw 16 absorbs any errors in the tooth profile, tooth thickness, etc. of the gear, so it eliminates uneven rotation due to this error and ensures smooth rotation. It comes to guarantee. Further, as in the above embodiment, if the elastic body 19 is interposed between the adjustment screw 16 and the shaft end of the intermediate shaft 10 (10') to receive the thrust, fine details such as tooth profile and tooth thickness can be adjusted. Since uneven rotation due to errors is instantaneously absorbed during rotation, even smoother rotation can be ensured.

In the embodiment described above, in order to increase the reduction ratio, the internal gear 12 is fixed and the rotation of the carrier 13 is controlled by the output shaft 2.
However, when the reduction ratio does not need to be so large, the carrier 13 is fixed to the casing 3 and the output shaft 2 fixed to the carrier 13 is
It is also possible to make the output shaft 2 freely rotatable, fix another gear to its output shaft 2, and simultaneously engage the gear 11.11' of the intermediate shaft 10.10'. Alternatively, the carrier 13 may be fixed to the casing 3 while the internal gear 12 may be rotatably configured to rotate integrally with the output shaft 2.

Further, in the above embodiment, one gear train consisting of gears 8, 9.9' is configured with a helical gear, and gears 11.11°
, 12 was made up of spur gears, but by reversing this, gears 8, 9, 9°
The gear train is composed of spur gears, and the gears 11, 11', 1
The second gear train may be composed of helical gears.

Furthermore, although the above-described embodiment is a case of a speed reduction device, if the output shaft 2 is used as an input shaft and the input shaft 2 is used as an output shaft, it can be used as a speed increase device.

[Structure of the invention]

As described above, in the present invention, a gear is fixed to one of the input and output shafts which are opposed to each other with their axial directions turned once, and to this gear,
Two gears individually fixed to each of the two intermediate shafts are meshed simultaneously to constitute one gear train, and a road wheel is fixed to each of the intermediate shafts, and these different gears are meshed simultaneously. , the other gear train is configured by simultaneously meshing with one gear that transmits variable speed transmission to the other of the input and output shafts, one of the two gear trains is configured with a helical gear, and the other is configured with a spur gear. In addition, since adjustment screws are provided at the ends of the two intermediate shafts to enable axial movement in opposite directions, the two intermediate shafts can be moved in opposite directions. , the meshing relationship of the gears can be made into a state equivalent to that of eight crushes.

Therefore, when switching between forward and reverse rotations, the switching can be done instantaneously without creating a time difference due to hacklash.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a transmission according to an embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view showing the adjusting screw mechanism of the same device, and FIG. 3 is a main part showing the thrust receiver of the adjusting screw mechanism. The sectional view and FIG. 4 are explanatory diagrams showing the meshing state of the gear train consisting of helical gears of the above-mentioned transmission. 1.--Human power shaft, 2.--Output shaft, 6. Engineering 3-...
Carrier, 8,9.9', 11.11"--gear, 12...-internal gear, 10.10"-intermediate shaft, 14
-・-adjustment screw mechanism, 16-adjustment screw, 17゜18...thrust receiver, 19-elastic body.

Claims (2)

[Claims] (1) A gear is fixed to one of the input and output shafts that are aligned in the same axial direction and are opposed to each other, and two gears that are individually fixed to two intermediate shafts are meshed with this gear at the same time. A gear train is constructed, and different gears are fixed to each of the intermediate shafts, and these different gears are simultaneously meshed with one gear that transmits variable speed transmission to the other input/output shaft to form a gear train of the other gear. , one of the gear trains is configured with a helical gear and the other is configured with a spur gear, and the ends of the two intermediate shafts are adjusted to enable axial movement in mutually opposite directions. A control transmission characterized in that each screw is provided. (2) The control transmission according to claim 1, wherein an elastic body such as a rubber material is interposed between the end of the intermediate shaft and the adjustment screw.