JP4699591B2 - Multi-axis indexing table - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multi-axis indexing table having a plurality of worm wheel shafts that act as output shafts, and in particular, a multi-axis in which worms meshing with worm wheels provided on each worm wheel shaft are connected in series in the direction of the axis. Concerning the index table.
[0002]
[Prior art]
As one of the multi-axis indexing tables provided with a plurality of worms, there is one in which worms adjacent in the axial direction are connected by a joint (Japanese Utility Model Publication No. 2-14921). In this prior art, a general shaft coupling is used in which the shaft end portions of both adjacent worms are received in the joint and the shaft end surfaces of both worms are connected to each other.
[0003]
[Problems to be solved]
In a conventional multi-axis indexing table using such a shaft coupling, the interval between adjacent circular tables is increased by the length dimension of the shaft coupling in the rotation axis direction, and a large installation space is required.
[0004]
Therefore, an object of the present invention is to save space by reducing the interval between adjacent circular tables in a multi-axis indexing table.
[0005]
[Solution, action and effect]
The multi-axis indexing table according to the present invention includes two adjacent worms connected to each other, each having a space formed coaxially with the axis of the worm and opened to the shaft end side at the connection side shaft end. And the connecting side shaft end of one worm contacts two worms fitted in the space of the other worm and the inner peripheral surface of the connecting side shaft end forming the space of the one worm. A pusher that comes into contact, a connection operation hole formed in the one or the other worm, the connection operation hole formed coaxially with the worm and reaching the space from the anti-connection side, and the connection operation hole A connecting operation body that is inserted from the side and reaches the pusher, and at least one of the outer peripheral surface of the pusher and the inner peripheral surface of the one worm has a tapered region.
[0006]
The rotary table is assembled to a worm wheel shaft spaced in the direction of the worm axis, and the worm wheel meshing with the worm is assembled to the worm wheel shaft. When the worm is rotated, the worm wheel is rotated, whereby the worm wheel shaft is rotated and the rotary table is rotated.
[0007]
The pusher is displaced in the axial direction of the worm by operating the connection operation body from the non-connection side. For this reason, the pusher that contacts the inner peripheral surface of one innermost worm is operated by fitting the connecting side shaft end portions of adjacent worms and operating the connecting operation body from the non-connecting side. Is displaced in the converging direction of the tapered region, the inner peripheral surface of one worm is expanded by the pusher, and a pressing force and a frictional force are generated between the mating surfaces of both worms. It is connected by.
[0008]
As a result, according to the present invention, there is no need to provide a coupling on the outer peripheral surface of the shaft end portion so that the shaft end surfaces of both worms face each other as in the prior art. It is possible to reduce the space between the tables to make a small space. Further, since the connecting operation body can be operated from the non-connecting side, the frame and the bearing do not hinder the connecting operation unlike the conventional coupling, and the connecting operation becomes easy.
[0009]
The opposite end of the worm through which the connection operation body passes is formed with the same fitting surface as the connection end of the worm connected to the worm, and is the same as the connection operation hole. The connection side shaft end portion of the third worm in which the connection operation hole is formed may be fitted into the space of the anti-connection side shaft end portion. By doing so, a worm having the same fitting surface as that of the connecting shaft end can be connected in series to the anti-connecting shaft end, and the fitting dimensions of the fitting surfaces can be made the same. it can.
[0010]
One of the adjacent worms is disposed on the drive source side and connected to the drive source, and the connection operation body is inserted into the connection operation hole from the other counter drive source side of the adjacent worms. Can do. By doing so, the worms can be connected in order from the drive source side, and the connection can be released in order from the worm on the counter drive source side. Even if it is connected to the drive source before connecting to the worm on the source side, the drive source does not hinder the connection work and the connection release work, the connection work of the worm to the drive source is facilitated, and When releasing the connection, it is not necessary to release the connection between the drive source and the adjacent worm.
[0011]
One of the pusher and the connection operation hole may have a female screw portion, and the connection operation body may have a male screw portion screwed into the female screw portion. By doing so, the pusher can be easily moved in the converging direction of the tapered region by rotating the connecting operation body.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the multi-axis indexing table 10 has a function of simultaneously driving three indexing table units 12, 14, and 16 by a drive motor 18 that acts as a common drive source.
[0013]
Each index base unit includes a frame 20, a worm wheel shaft 22 rotatably supported by the frame 20, a circular table 24 outside the frame 20 and assembled to the worm wheel shaft 22, The worm wheel 26 is assembled to the worm wheel shaft 22 and the worm 28 is engaged with the worm wheel 26 in the frame 20.
[0014]
The frames 20 of adjacent index base units are connected to each other by a unit connecting ring 30 so that the index base units 12, 14, and 16 are combined in series.
[0015]
Each worm 28 includes shaft end portions 36 and 38 that are rotatably and coaxially assembled to the frame 20 by bearings 32 and 34. In the illustrated example, the bearing 32 is a roll bearing, and the bearing 34 is a ball bearing mounted on the frame 20 by a bearing housing 40.
[0016]
Each worm 28 has worm teeth that mesh with the teeth of the worm wheel 26 on the outer periphery. Each worm 28 has slightly different leads on the left and right tooth surfaces, and thus the thickness of the worm teeth is gradually increased toward one side (for example, the drive motor 18) in the direction of the axis 42 of the worm 28. Of the formula.
[0017]
The worms 28 of the adjacent index base units are coaxially connected at the shaft end portions 36 and 38 by a connecting device described later. For this reason, the worms 28 of the index base units 12, 14, and 16 are connected in series.
[0018]
The worm 28 of the index base unit 12 on the most drive source side (motor 18 side) has a gear 44 assembled to the shaft end portion 36 on the drive source side. The gear 44 meshes with a gear 46 assembled to the worm wheel shaft of the drive motor 18. An end plate 48 that covers the rotating portion is attached to the frame 20 of the index base unit 16 on the most counter drive source side (counter motor 18 side) by a plurality of screw members.
[0019]
As shown in detail in FIG. 2, each bearing housing 40 is assembled to the counter drive source side of the frame 20 by a plurality of assembly bolts 50, and the space between the bearing housings 40 is maintained by a plurality of adjustment screws 52. is doing. The assembly bolt 50 and the adjustment screw 52 are spaced equiangularly around the axis 42 of the worm 28.
[0020]
The adjusting screw 52 is used for adjusting the backlash between the worm wheel 24 and the worm 28. In this backlash adjustment, by adjusting the screwing amount of the adjusting screw 52 into the bearing housing 40, the bearing housing 40 is moved in the direction of the axis 42, the bearing 34 and the worm 28 are moved, and the teeth of the worm wheel 26 are moved. Is engaged with the worm 28 having a tooth thickness that results in optimum backlash.
[0021]
As shown in detail in FIGS. 2 and 3, each connecting device for connecting adjacent worms 28 is formed coaxially with the worm 28 at shaft end portions 36, 38 on the connecting side of the two adjacent worms 28. Space 54, 56, a spreader member or pusher 58 that is in contact with the inner peripheral surface of one shaft end 36 and presses the shaft end 36 against the inner peripheral surface of the shaft end 38; The worm 28 includes a connection operation hole 60 formed so as to pass through the worm 28 coaxially, and a connection operation body 62 inserted into the connection operation hole 60 from the opposite end of the connecting shaft.
[0022]
The spaces 54 and 56 are each opened to the shaft end side. The inner peripheral surface of the shaft end portion 36 that forms the space 54 converges toward the back of the space 54 on the anti-connection side (inner diameter dimension is smaller at the back side of the space 54), and has a truncated conical shape. have. The inner peripheral surface of the shaft end portion 38 that forms the space 56 has the same inner diameter in the axial direction. The shaft end 36 has an outer diameter that is substantially the same as the inner diameter of the space of the shaft end 38, and is fitted in the space 56 so as to be movable in the axial direction.
[0023]
The pusher 58 has a frustoconical shape corresponding to the shape of the inner peripheral surface of the shaft end portion 36, and has a screw hole that passes through the pusher 58 coaxially. At least a part of the inner peripheral surface of the shaft end portion 36 and the outer peripheral surface of the pusher 58 forms a tapered region and is in contact with each other. In the illustrated example, the tapered region converges on the far side of the space 54 on the anti-connection side.
[0024]
The connection operation hole 60 is a through hole that reaches the space 54. The connection operation body 62 is a bolt having a head 64 for operation and having a male screw portion 66 at the tip, and is passed through a washer 68. The connection operation body 62 is inserted into the connection operation hole 60 from the opposite connection side of the worm 28, and the male screw portion 66 is screwed into the screw hole of the pusher 58.
[0025]
The worms 28 of the index base units 14 and 16 have the same shape. The worm 28 of the index base unit 12 is the same except that the structure of the shaft end portion 36 on the drive source side is different from the worm 28 of the other index base units 14 and 16 and that there is no connection operation hole. It is.
[0026]
In the above connecting device, before the shaft end portion 36 is inserted into the shaft end portion 38, the connection operating body 62 is operated in advance to press the pusher 58 weakly against the inner peripheral surface of the shaft end portion 36, thereby the pusher 58 A frictional force is generated between the inner surface and the inner peripheral surface to prevent the pusher 58 from rotating when the connecting body 62 is rotated.
[0027]
After that, when the shaft end portion 36 is fitted to the shaft end portion 38 and the rotation of the pusher 58 with respect to the worm 28 is prevented by the frictional force, the connecting operation body 62 is rotated around the axis line 42, and the pusher 58 is moved to the pusher 58. Since the screwing amount of the connection operation body 62 changes, the pusher 58 is moved in the direction opposite to the connection side, which is the convergence direction of the tapered region in the direction of the axis 42 with respect to the worm 28.
[0028]
When the pusher 58 is moved toward the back of the space 54 with respect to the worm 28 by the rotation of the connecting operation body 62, the pusher 58 is in a state where its outer peripheral surface is in contact with the inner peripheral surface of the shaft end portion 36. Since the shaft end portions 36 and 38 are moved in the converging direction of the tapered region, the shaft end portion 36 is expanded radially outward so that the outer peripheral surface of the shaft end portion 36 is the inner periphery of the shaft end portion 38. Press against the surface. As a result, a frictional force is generated between the outer peripheral surface of the shaft end portion 36 and the inner peripheral surface of the shaft end portion 38, and the adjacent worms 28 are connected so as not to be relatively rotatable by the frictional force.
[0029]
On the contrary, when the pusher 58 is moved toward the opening side of the space 54 with respect to the worm 28, the pusher 58 is separated from the inner peripheral surface of the shaft end portion 36. The pressing of the inner peripheral surface of the shaft end portion 36 to the surface is released. As a result, the frictional force is eliminated or reduced between the outer peripheral surface of the shaft end portion 38 and the inner peripheral surface of the shaft end portion 38, and the adjacent worms 28 are disconnected and separated so as to be relatively rotatable. .
[0030]
In the index table 10, the index table units 12 and 14 are first connected, and then the index table unit 16 is connected to the index table unit 14. The index base unit 12 and the drive motor 18 may be coupled before the index base units 12 and 14 are coupled, or may be coupled after the coupling. Separation of the index base unit is performed from the unit on the counter driving source side.
[0031]
Prior to connecting the index base units 12 and 14, the backlash between the worm wheel 26 and the worm is adjusted for each unit by using the assembly bolt 50 and the adjusting screw 52, and adjacent to each other at the time of connection. Phase alignment of the circular tables of the indexing unit is performed.
[0032]
The above embodiment may be modified as follows.
[0033]
Instead of making both the inner peripheral surface of the shaft end portion 36 and the outer peripheral surface of the pusher 58 into a frustoconical shape as a tapered region, only one of them, for example, only the outer peripheral surface of the pusher 58 as shown in FIG. May be a frustoconical shape to form a tapered region. In this case, it is preferable to perform arc-shaped or linear chamfering processing on the tip of the inner peripheral surface of the shaft end portion 36.
[0034]
Instead of screwing the male threaded portion 66 of the coupling operating body 62 into the screw hole of the pusher 58, a part of the coupling operating hole 60 is made into a screw hole 70 and the male threaded portion 66 is screwed into the screw hole 70 as shown in FIG. The pusher 58 may be assembled so as to be immovable in the axial direction at the distal end of the connection operating body 62 by an assembly tool such as the male screw portion 72 or the nut 74.
[0035]
As shown in FIG. 6, a plurality of slits 76 are formed on the shaft end portion 36 that is spread by the pusher 58 so as to extend from the shaft end in the direction of the axis 42, so that the shaft end portion 36 is radially moved by the pusher 58. The structure may be easily pushed outward.
[0036]
As shown in FIG. 7, the inner peripheral surface of the shaft end portion 36 and the outer peripheral surface of the pusher 58 may be used as a tapered region by forming a frustoconical shape converging in the connecting side direction of the worm 28. .
[0037]
Further, as shown in FIG. 8, the inner peripheral surface of the shaft end portion 38 of the worm 28 connected to the worm 28 into which the connecting body 42 is inserted is the innermost inner peripheral surface, and a pusher 58 is applied to the inner peripheral surface. You may contact. In this case, when the pusher 58 presses the inner peripheral surface of the shaft end portion 38, the worms 28 may be relatively separated by a reaction force. Therefore, it is preferable to reduce the inclination angle of the tapered region.
[0038]
The present invention is not limited to the above embodiments. For example, a connecting operation body other than a bolt may be used. The present invention can be variously modified without departing from the gist thereof.
[Brief description of the drawings]
FIG. 1 is a sectional view showing an embodiment of a multi-axis indexing table according to the present invention.
FIG. 2 is an enlarged cross-sectional view of a main part of the multi-axis indexing table shown in FIG.
FIG. 3 is a cross-sectional view showing an embodiment of a worm coupling device used in the multi-axis indexing table shown in FIG.
FIG. 4 is a sectional view showing a second embodiment of the worm coupling device.
FIG. 5 is a sectional view showing a third embodiment of the worm coupling device.
6A and 6B are diagrams showing a fourth embodiment of the worm coupling device, in which FIG. 6A is a cross-sectional view, and FIG. 6B is a cross-sectional view taken along line 6B-6B of FIG.
FIG. 7 is a cross-sectional view showing a fifth embodiment of the worm coupling device.
FIG. 8 is a sectional view showing a sixth embodiment of the worm coupling device.
[Explanation of symbols]
10 Multi-axis indexing table 12, 14, 16 Indexing table unit 18 Drive motor 20 Frame 22 Worm wheel shaft 24 Rotary table 26 Worm wheel 28 Worm 36, 38 Shaft end 42 Axis 54, 56 Space 58 Pusher 60 Connection operation hole 62 Linking operation body

Claims (4)

Two adjacent worms connected to each other, each of which has a space formed in the same axis as the axis of the worm and opened to the shaft end side at the connection side shaft end portion, and the connection side shaft end portion of one worm. Two worms fitted in the space of the other worm,
A pusher that comes into contact with the inner peripheral surface of the connecting-side shaft end portion that forms the space of the one worm;
A connection operation hole formed in the one or the other worm, the connection operation hole formed coaxially with the worm and reaching the space from the opposite connection side,
A connection operation body that is inserted into the connection operation hole from the opposite connection side and reaches the pusher,
At least one of the outer peripheral surface of the pusher and the inner peripheral surface of the one worm has a tapered region. The opposite end of the worm through which the connection operation body passes is formed with the same fitting surface as the connection end of the worm connected to the worm, and is the same as the connection operation hole. The multi-axis indexing table according to claim 1, wherein a connection side shaft end portion of a third worm having a connection operation hole is fitted in the space of the anti-connection side shaft end portion. One of the adjacent worms is disposed on the drive source side and connected to the drive source, and the connection operation body is inserted into the connection operation hole from the other counter drive source side of the adjacent worms. The multi-axis indexing table according to claim 1 or 2. 4. The multi-axis indexing device according to claim 1, wherein one of the pusher and the connection operation hole has a female screw portion, and the connection operation body has a male screw portion screwed into the female screw portion. Stand .

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