JP2020106062A - Device for positioning rotation of rotational shaft - Google Patents

Abstract

To provide a device for positioning the rotation of a rotational shaft, which positions a rotational shaft with higher accuracy while motion is stopped.SOLUTION: A device for positioning the rotation of a rotational shaft comprises a first driven member and a second driven member which are arranged side by side so as to be adjacent to each other, and are relatively movable. The first driven member and the second driven member are arranged so as to be displaced from each other, have tooth rows, and are configured to mesh with a gear at the same time. When the first driven member and the second driven member receive forces opposite to each other, the gear is sandwiched and pressed to prevent rattling. When the gear is a part of the rotational shaft, and one end of the rotational shaft is coupled to a target member, the target member can rotate, and when it rotates to a positioning point, it can be positioned accurately without rattling.SELECTED DRAWING: Figure 4

Description

The present invention relates to a power transmission device, and more particularly to a power transmission device for a gear that can be rotationally positioned with respect to a rotation shaft.

A power transmission device refers to a device that can change the motion mode, direction or speed of power, and usually uses friction between mechanical members to transmit power or moves or drives the mechanical members. In some cases, the power may be transmitted by meshing. The meshing power transmission device is widely used in machine tools because it can reliably transmit a motion by meshing between the convex teeth and can be applied to a high load.

In the conventional gear power transmission device shown in FIGS. 1 to 3, the reciprocating motion of the racks (Racks) 1 causes the pinions 2 meshing with the racks 1 to rotate in the forward and reverse directions. The above arrangement method converts linear motion into rotation, and when the pinion 2 is a part of the rotary shaft 3, the target member coupled to one end of the rotary shaft 3 is rotated correspondingly. .. Taking the exchanging arm 4 of the machine tool as an example, it is connected to one end of the rotary shaft 3 and rotates along with the rotary shaft 3 to perform tool exchange. However, when the exchange arm 4 is stopped, there is a backlash G at a portion where the convex tooth 1a of the rack 1 and the convex tooth 2a of the pinion 2 mesh with each other, so that there is still a minute turning space with respect to the rotating shaft 3. Due to the above situation, the exchange arm 4 may not be rattled and may not be accurately positioned at the stop position. This is not limited to the case where the target member is an exchange arm, and for example, when the target member is a turntable, there is backlash, so that excellent stability cannot be maintained even when the motion is stopped.

In view of this, it is an object of the present invention to provide a rotary positioning device for a rotary shaft that positions the rotary shaft with excellent accuracy while the motion is stopped.

In order to achieve the above object, in a rotary positioning device for a rotary shaft having a gear according to the present invention, a first driven member having a first tooth row and a first driven member are arranged side by side and side by side. And a second driven member having a second tooth row, wherein the first driven member receives a force in a first direction and the second driven member receives a force in a second direction opposite to the first direction. The gear of the rotary shaft is configured to mesh with the first and second tooth rows at the same time so that the first and second tooth rows sandwich the gear.

When the first driven member and the second driven member can move relative to each other and receive mutually opposite forces, the gears are sandwiched and pressed so that rattling does not occur.

It is a top view of the conventional gear power transmission device. It is a front view of FIG. FIG. 3 is a partially enlarged view of part A of FIG. 2. It is a perspective view showing arrangement of a rotation positioning device and a rotation shaft concerning a preferred embodiment of the present invention. FIG. 5 is a top view of FIG. 4. It is a partial front view of FIG. FIG. 6 is an exploded view of a rotary positioning device and a rotary shaft according to another preferred embodiment of the present invention. FIG. 8 is an assembled perspective view of the member of FIG. 7. FIG. 9 is a sectional view taken along the line 9-9 of FIG. 8. FIG. 9 is a partial cross-sectional top view of FIG. 8. FIG. 10 is a partially enlarged view of FIG. 9. It is a top view of the partial cross section of FIG. FIG. 11 is a partially enlarged view of FIG. 10. It is a figure similar to FIG. 10 which shows the rotation state of a rotating shaft. It is a figure similar to FIG. 11 which shows the rotation state of the rotating shaft of FIG. It is a partially expanded view of the B section and C section of FIG. It is a partially expanded view of the B section and C section of FIG. FIG. 6 is a perspective view showing a rotary positioning device including a positioning ring and a bias member.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The rotary positioning device 100 shown in FIGS. 4 to 6 is used for the power transmission rotary shaft 200, and the rotary shaft 200 has a gear 201, and one end of which is connected with a target member (not shown). The target member can be rotated in conjunction with each other. Depending on the case of use, the target member can be positioned with high accuracy when the machine tool replacement arm or other rotation and then stop.

The rotary positioning device 100 includes the first driven member 10 and the second driven member 20 that are arranged side by side and adjacent to each other and are movable relative to each other, and the first driven member 10 has the first tooth row 12. However, the second driven member 20 has the second tooth row 22, and the gear 201 of the rotary shaft 200 meshes with the first tooth row 12 and the second tooth row 22 at the same time. In the present embodiment, the gear 201 is a spur gear having a plurality of meshing teeth 201a arranged along the circumference, and the first driven member 10 and the second driven member 20 are parallel shafts (Parallel). The racks are racks that are independent of each other and are arranged in the “shafts”. When the rotation of the rotary positioning device 100 is stopped and the rotation shaft 200 stops rotating, the first driven member 10 receives the force F1 in the first direction, and the second driven member 20 is opposite to the first direction. It receives a directional force F2. By arranging the first tooth row 12 and the second tooth row 22 at different positions, backlash can be removed, and the gear 201 is pressed and held stably without rattling and is coupled to one end of the rotary shaft 200. It is possible to accurately position the target member member that is present. One of the force F1 in the first direction and the force F2 in the second direction is an acting force and the other is a reaction force, but the pressure source F1 in the first direction and the force F2 in the second direction are different from each other. May be generated by

As shown in FIGS. 7 to 10, in the rotary positioning device 100 according to the embodiment, in addition to the first driven member 10 and the second driven member 20, a rotation pedestal 30, a cylinder body 40, and a first driven member 10 are provided. The pressure cylinder 50, the second pressure cylinder 60, the first pressing member 70, the second pressing member 80, and the control module 90 are further included. The rotating pedestal 30 is located at the center and has a shaft hole 32. The rotating shaft 200 fitted on the bearing 202 and the seal ring 203 rotatably passes through the shaft hole 32. One end of the rotation shaft 200 penetrates the rotation pedestal 30 and is coupled to a target member (for example, an exchange arm). Opposite opposite sides of the rotating pedestal 30 are respectively connected to a cylinder-shaped cylinder main body 40, and the ends of the two cylinder main bodies 40 opposite to the ends adjacent to the rotating pedestal 30 are The first pressurizing cylinder 50 and the second pressurizing cylinder 60 are respectively connected, and the first pressing member 70 and the second pressing member 80 that move along the axial direction are arranged in each cylinder body 40. Therefore, the control module 90 applies the force F1 in the first direction from the first pressurizing cylinder 50 to the first pressing member 70, or the force F2 in the second direction from the second pressurizing cylinder 60 to the second direction. The pressing member 80 is controlled so as to act on it. The force F1 in the first direction and the force F2 in the second direction are generated by hydraulic pressure or air pressure. The control module 90 may include a solenoid valve for switching the flow of hydraulic oil or gas. That is, when one of the first pressurizing cylinder 50 and the second pressurizing cylinder 60 generates a directional force, the other pressurizes.

The first driven member 10 and the second driven member 20 of the present embodiment are racks having the same length, and the first tooth row 12 of the first driven member 10 is a plurality of first teeth arranged in the axial direction. Each of the first convex teeth 14 has a first front tooth surface 14a and a first rear tooth surface 14b facing opposite to each other. The root portion 16 is formed, the second tooth row 22 of the second driven member 20 is composed of a plurality of second convex teeth 24 arranged along the axial direction, and the second convex teeth 24 are on opposite sides of each other. The second tooth flank portion 26 is formed between two adjacent second convex teeth 24 having the second front tooth surface 24a and the second rear tooth surface 24b facing toward each other. The pitch of the first tooth row 12 and the pitch of the second tooth row 22 are the same, but the first tooth row 12 and the second tooth row 22 are not completely aligned, that is, the first driven member 10 When both ends of the second driven member 20 are aligned with each other, the positions of the first tooth row 12 and the second tooth row 22 are displaced. However, the difference in misalignment is formed so that one meshing tooth enters the corresponding first tooth root portion 16 and second tooth root portion 26.

The first driven member 10 and the second driven member 20 are horizontally and adjacently penetrated through the through holes 34 of the rotation pedestal 30, and both ends of the first driven member 10 and the second driven member 20 are arranged so as to enter the cylinder body 40 and be orthogonal to the rotation shaft 200. ing. The first driven member 10 and the second driven member 20 are located between the first pressing member 70 and the second pressing member 80 as pistons. The first pressing member 70 has a first pressing surface 72 that is in contact with one end of the first driven member 10, and the second pressing member 80 is a second pressing member that is in contact with one end of the second driven member 20. It has a face 82. In the rotary positioning device 100 shown in FIGS. 9 and 10, the force F1 in the first direction from the first pressure cylinder 50 acts on the first pressing member 70, and then the first pressing member 70 is driven by the first driven member 70. The member 10 is pressed to the right. Since the binder 60 is in the pressure release state, the second pressing member 80 stops on the inner wall of the second pressure cylinder 60, and the second driven member 20 receives the reaction force (that is, the force F2 in the second direction). Further, as shown in FIGS. 11 to 13, when the control module 90 stops the control and also stops the motions of the first driven member 10 and the second driven member 20, the first front tooth surface of the first convex tooth 14 is formed. 14a and the 2nd back tooth surface 24b of the 2nd convex tooth 24 are each contact|abutted to the tooth surface on both sides which the corresponding meshing tooth 201a of the 1st radial line L1 opposes in the front-back direction. At this time, since the meshing tooth 201a has no backlash between the first convex tooth 14 and the second convex tooth 24, the rotary shaft 200 stops rotating and rattling does not occur, and the rotary shaft 200 maintains a stable state. The target member connected to one end can be accurately positioned. Further, since the first tooth row 12 and the second tooth row 22 are arranged so as to be displaced from each other, the other end of the first driven member 10 is arranged so as to separate the second pressing surface 82 and the gap G1. The other end of the second driven member 20 is arranged so as to have the same gap G1 as the first pressing surface 72.

By rotating the rotary shaft 200, the control module 90 causes the force F2 in the second direction from the second pressurizing cylinder 60 to act on the second pressing member 80 so that the first pressurizing cylinder 50 is in the pressure releasing state. When controlling, as shown in FIG. 14, the force F1 in the first direction disappears in this process, and the force F2 in the second direction is not a reaction force. Therefore, the second pressing member 80 presses the second driven member 20 to the left so as to move the second convex member 24 and the meshing tooth 201a along the linear direction. As shown in FIG. 15, at this time, in the process in which the meshing tooth 201a originally located on the first radial line L1 is deflected to the second radial line L2, the first driven member 10 is driven by the second driven member 10. It is pressed synchronously so that it moves along the same translation direction as the member 20. While the second driven member 20 presses the gear 201 in the linear direction, the gear 201 rotates to press the first driven member 10, so that the first driven member 10 has a slightly larger moving stroke than the second driven member 20. As shown in FIGS. 16A and 16B, in this case, one end of the first driven member 10 (second driven member 20) that does not contact the second pressing surface 82 (first pressing surface 72) has the second pressing surface 82 (first The gap G2 between the first pressing surface 72) is slightly larger than the gap G1 in the state shown in FIG. 13 described above, and the first convex tooth 14 is close to the position where the second convex tooth 24 is superposed. Thus, the backlash is provided between the meshing teeth 201a of the gear 201 and the convex teeth, and the first driven member 10 and the second driven member 20 smoothly mesh with the rotating shaft 200 to rotate the rotating shaft 200. You can

When the first pressing member 70 moves to the inner wall of the first pressurizing cylinder 50, the control module 90 stops the control operation, and the second pressing member 80 continues to move from the hydraulic pressure or the pneumatic pressure in the cylinder body 40 in the second direction. In response to the force F2, the first pressing member 70 is stopped by the inner wall of the first pressurizing cylinder 50, so that the first pressing member 70 receives a reaction force (that is, a force F1 in the first direction). In this case, the distance between the one end of the driven member and the pressing surface of the pressing member is reduced to the gap G1 again, whereby the first front tooth surface 14a of the first convex tooth 14 and the first convex tooth 24 of the second convex tooth 24 are again formed. The two rear tooth surfaces 24b are in contact with the opposite tooth surfaces of the meshing teeth corresponding to the front-rear direction. As a result, the rotation control of the rotary shaft 200 is completed, the rotary shaft 200 stops rotating, and rattling does not occur, and a stable state is maintained.

As can be seen from the above, according to the present invention, the first driven member 10 and the second driven member 20 which are arranged side by side and adjacent to each other and which are relatively movable are engaged with the power transmission gear 201 synchronously. When the power transmission gear 201 is rotated and one of the driven members is stopped and cannot move forward, the acting force and the reaction force are respectively received, so that the engagement tooth 201a of the gear 201 is sandwiched and pressed to suppress the looseness. Specifically, when the target member coupled to one end of the rotary shaft 200 is an exchange arm, when the exchange arm rotates to the positioning point, the alignment is accurately performed without slight rattling.

As shown in FIG. 17, in the above-described embodiment, the first driven member 10 and the second driven member 20 may be externally fitted together by at least one positioning ring 18 so as to stabilize their relative positions. .. In FIG. 17, both ends of the driven member are fitted by two positioning rings. Further, a bias member 36 for biasing the bias pressure to the first driven member 10 and the second driven member 20 may be further provided on the rotating pedestal 30 so as to maintain a good meshing relationship between the gear and the tooth row. .. The bias member 36 has a contact surface 36a that conforms to the contours of the first driven member 10 and the second driven member 20. Bias pressure is obtained from springs or adjustable bolts that are screwed into the threaded holes of the pedestal 30 for rotation.

In the above-described embodiment, the rotating shaft is rotated by the rack of teeth arranged in a straight line, but in another embodiment, the rotating shaft is rotated by a combination of internal gears and spur gears. It may be rotated, i.e. the gear of the rotating shaft is still a spur gear, the first driven member and the second driven member are respectively arranged side by side and adjacent to each other, having the same center of rotation as the spur gear and relatively rotating. It is an internal gear that can be. The tooth rows of the internal gear are annular and are arranged so as to be displaced from each other. With the above-described structure, the rotary shaft can be rotated as in the above-described embodiment, and in the stopped state, the effect of the position regulation is exerted on the rotary shaft, and rattling does not occur.

What has been described above are only preferred feasible embodiments of the present invention, and equivalent modifications of the specification and claims of the present invention should be included in the claims of the present invention.

100 rotation positioning device 10 first driven member 12 first tooth row 14 first convex tooth 14a first front tooth surface 14b first rear tooth surface 16 first tooth trough 18 positioning ring 20 second driven member 22 second tooth row 24 2nd convex tooth 24a 2nd front tooth surface 24b 2nd back tooth surface 26 2nd tooth root part 30 rotation base 32 shaft hole 34 through hole 36 bias member 36a contact surface 40 cylinder main body 50 first pressurizing cylinder 60th Two pressurizing cylinders 70 First pressing member 72 First pressing surface 80 Second pressing member 82 Second pressing surface 90 Control module 200 Rotating shaft 201 Gear 201a Engaging tooth 202 Bearing 203 Seal ring G1, G2 Gap F1 Force in first direction F2 second direction force L1 first radial line L2 second radial line

Claims (9)

In a rotary positioning device for a rotary shaft having a gear,
A first driven member having a first tooth row, and a second driven member having a second tooth row that is arranged laterally and adjacent to the first driven member,
When the first driven member receives a force in the first direction and the second driven member receives a force in a second direction opposite to the first direction, the first tooth row and the second tooth row are A rotary positioning device for a rotary shaft, wherein the gear of the rotary shaft is configured to mesh simultaneously with the first tooth row and the second tooth row so as to sandwich the gear. The rotary positioning device for a rotary shaft according to claim 1, wherein one of the force in the first direction and the force in the second direction is an acting force and the other is a reaction force. Further comprising a first pressing member having a first pressing surface and a second pressing member having a second pressing surface,
The first driven member and the second driven member are arranged between the first pressing member and the second pressing member, one end of the first driven member is in contact with the first pressing surface. And the other end is arranged so as to be separated from the second pressing surface by a gap, the second driven member has one end abutting against the second pressing surface, and the other end is the first pressing surface. The rotary positioning device for a rotary shaft according to claim 2, wherein the rotary positioning device is arranged so as to be spaced apart from the space. Further comprising a first pressure cylinder and a second pressure cylinder,
When a force in the first direction is applied from the first pressure cylinder to the first driven member, a reaction force is applied from the second pressing member to the second driven member, and the second pressure cylinder causes the second driven member to react. The rotational positioning of the rotating shaft according to claim 3, wherein when a force in two directions is applied to the second driven member, a reaction force is applied from the first pressing member to the first driven member. apparatus. The rotating shaft according to claim 4, further comprising a control module that controls one of the first pressurizing cylinder and the second pressurizing cylinder so that when the other one generates a directional force, the other pressurizes. Rotation positioning device. The gear of the rotating shaft has a plurality of meshing teeth arranged along the circumference, and the first tooth row of the first driven member has a plurality of first convex teeth arranged along the axial direction. And a first tooth root portion is formed between two adjacent first convex teeth, and the second tooth row of the second driven member has a plurality of first tooth rows arranged along the axial direction. It has two convex teeth and a second tooth root is formed between two adjacent second convex teeth, and the meshing teeth are the corresponding first root and second root. 6. The rotary positioning device for a rotary shaft according to claim 2, wherein the root portion and the second root portion are arranged at different positions. Each of the first convex teeth has a first front tooth surface and a first rear tooth surface facing opposite sides, and each of the second convex teeth has a second front tooth surface and a second front tooth surface facing opposite sides. Having two posterior tooth surfaces, the first anterior tooth surface of the first convex tooth and the second posterior tooth surface of the second convex tooth are respectively abutted on the opposite tooth surfaces of the corresponding meshing tooth, 7. The rotation according to claim 6, wherein the first rear tooth surface of the first convex tooth and the second front tooth surface of the second convex tooth are in contact with opposite tooth surfaces of the corresponding meshing tooth. Shaft rotation positioning device. 7. The rotary positioning device for a rotary shaft according to claim 6, wherein at least one positioning ring is fitted on both the first driven member and the second driven member. 7. The bias member according to claim 6, further comprising a bias member that applies a bias pressure to the first tooth row and the second tooth row so as to mesh the first tooth row and the second tooth row with the gear. A rotary positioning device for a rotary shaft.

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