JP2006125611A - Spline ball screw and clutch connecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate control by introducing a tooth clutch connection for connecting a spline ball screw. <P>SOLUTION: The ball screw is provided with a spline groove, thereby surely connecting a ball screw nut and the ball screw to each other, and the connection between a moving bed side and the ball screw nut is also secured by clutch connection. A gear train is connected to the ball screw nut to thereby easily take turning force of the ball screw and control the moving bed in releasing clutch connection. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The conventional ball screw is used to move a moving body, on which a ball screw nut is fixed by rotation of the ball screw, back and forth along the ball screw axis in order to reduce friction of normal screw coupling. This proposal is related to the improvement of the ball screw connection.

Japanese Patent Laid-Open No. 7-208572 (page 1-5, FIG. 1) In a ball screw device and a table driving device provided with the ball screw device, a ball screw nut supported by a bearing that is fitted to a long-axis ball screw is assembled to a movable table. The ball screw nut is rotated by a motor mounted on the moving table, and the moving table slides along the ball screw. The issue of this patent is that the long-axis ball screw vibrates due to the rapid movement of the moving table, so the idea is to converge it. Since it is a normal usage method to rotate the ball screw nut from the outside and drive the moving table, rotation introduction itself does not fall under the patent. JP-A-9-253969 (pages 1-7, FIG. 1) In order to facilitate a wide range of movement of a table with a ball spline, that is, a moving table driven by a ball screw, a wide range of rapid movement is possible using a spline shaft incorporating a moving ball. In addition, local precision movement is a complex device that employs a ball screw. The spline shaft and the ball screw shaft are independent. Japanese Utility Model Publication No. 6-6793 (first page) This is a proposal for suppressing the vibration of the ball screw shaft by coating the outer surface of the ball screw shaft with a material having a large vibration damping rate, such as lead plating, in the damping type feed ball screw shaft. Japanese Patent Laid-Open No. 8-200377 (pages 1-4, FIG. 1) In a vehicle transmission synchronizer, switching of meshing of rotating bodies adjacent to each other on the same axis on the same axis is performed synchronously during rotation. When employed in an automobile or the like, the synchronization device of Patent Document 4 has a large coupling torque of the rotating bodies. Therefore, a method of obtaining the rotation speed synchronization is employed. Issued by Ikegai Tsumugi Co., Ltd., Ikekai Technique, August 1965 issue, 10-P. 40 It is reported that a ball screw is used as a lead screw for turret driving on the Ikenai A20 type lathe. Details of the structure related to the lead screw (ball screw) are not described. Published by Toru Ito, signpost for manufacturing nations, issued on March 22, 2003, not for sale 16-P. 80 The detailed design details of the Ikegai A20 type lathe are told. Here, a ball screw is used as a lead screw, and at the same time, a saddle with a tool post, that is, a movable stand, is introduced with a separate drive system. The lead screw does not rotate and is shown to be fixed.

When using ball screw male / female movement settings, the relative movement of the male / female ball screws constrained on the screw shaft can be controlled independently or independently by applying rotational motion from the outside. As a result. Here, mechanically fixing the male screw and the female screw is not normally performed because the purpose of the moving mechanism is lost. However, by temporarily fixing the male and female screws, there was a structural need to extract the rotation of the male screws synchronously. The present invention solves this problem. The following items 0004 to 0008 are analyzed for differences from published patents.

In the proposed patent device, a toothed clutch that connects a ball screw and a ball screw nut with a clutch, leads the rotation of the ball screw to the outside with a gear connected to the ball screw nut, and combines the ball screw nut and the ball screw is provided. When it is open, rotation from the outside results in normal ball screw usage to drive the ball screw nut, but when the ball screw and ball screw nut are connected by a toothed clutch, it is not normal usage but the ball A rotational output that is completely synchronized with the rotation of the screw is derived into the moving body, and the content of Patent Document 1 does not limit Claim 2 of this time.

This time, the difference between the method of processing the spline groove and imparting it to the ball screw itself proposed in claim 1 and the content of patent document 2 can be seen. The structure for introducing the spline shaft independent of the ball screw is completely different in purpose and structure. Therefore, Patent Document 2 is not intended to constrain Claim 1 of the present proposal for processing spline grooves on the outer peripheral surface of the ball screw.

The purpose and structure of Patent Document 3 is focused on preventing vibrations that occur during high-speed rotation of the ball screw. On the contrary, the processing of the outer shape of the ball screw intended by claim 1 of the proposed patent is the purpose of constructing a spline groove and mounting a clutch that slides on the same axis. It is the purpose of another dimension. Accordingly, there is no restriction on the billing item 1 proposed at this time.

The purpose of obtaining the rotational speed synchronization of the different types of rotating bodies existing on the same axis is the same as the device claimed in this patent application and the claim 3. But the method is different. The device of claim 3 proposed this time has a relatively small relative rotational speed and a small coupling torque, so that the structure for obtaining friction is simple. Details are left to the description of the drawings, but it is easy to synchronize with the tooth-shaped coupling guide ball in the ball retainer fitted to the sliding conical shaft and to synchronize the tooth-shaped clutch facing with the comb-shaped guide ball groove. Therefore, the present claim 3 and the clutch mechanism of an automobile or the like are of different dimensions and do not become a limiting factor.

I came up with the proposed patent during my research on the Ikekai A-20 lathe. The Ikegai type 20 lathe is a typical general-purpose lathe in Japan, but because it is a large machine, the turret that moves on the lathe bed is driven by a separate control axis at the same time as the ball screw used for the lead screw. In the A20 type, the lead screw is fixed and the ball screw nut is driven from the outside via the control shaft. However, the external drive shaft is adopted for drive control of the various tool rests on the moving table, and the lead screw (ball It can be said that the screw) was not necessary because it is a large machine with abundant drive resources that is not on the drive shaft. Therefore, it is not necessary to simplify the control relationship structure by coupling the lead screw, that is, the ball screw and the ball screw nut, and the clutch coupling is not employed. Therefore, this claim 1 is not constrained.

When the coupling of the ball screw 1 with spline groove and the bolt screw nut 5 of the present proposal is neutral and mutual rotation is free, the ball screw nut 5 and the tooth-shaped clutches A3 and B4 or the tooth-shaped clutches C7 and D9 as shown in FIG. This is the case where there is no connection. Specifically, this indicates a case where the positions of the clutch D side and A side switching levers 17 and 24 coupled by the lever connecting rod 21 are not in the positions of 18, 25 or 20, 27. The neutral state is obtained by setting the clutch D side and A side switching lever positions to 19 and 26.

When the tooth-shaped clutch for coupling the splined ball screw 1 and the ball screw nut 5 is in a neutral state, that is, the tooth-shaped clutch can be freely coupled. The ball screw nut 5 can be moved back and forth on the axis of the ball screw by a rotational force introduced from the outside through the rotational input / output shaft 23 to the ball screw nut 5 via the gear coupling, that is, the movable table 6 is driven. This is performed by an external rotational force independent of the rotational force of the ball screw 1.

A ball screw nut 5 to be fitted to the splined ball screw 1 is attached to the moving table 6 through a bearing. As a result, the relationship between the ball screw rotation direction 2 of the splined ball screw 1 and the movement of the movable table 6 can be separated by the tooth-shaped clutch connection. The ball screw nut 5 is meshed with the tooth-shaped clutch C7 and the tooth-shaped clutch D9 fitted in the guide cylinder 8 with spline on the movable table coupled to the movable table 6, or meshed with the tooth-shaped clutches A3 and B4 fitted with the ball screw. And reciprocal selection. That is, one of the two tooth clutch couplings in the front and rear of the combination 7, 9 or 3 or 4 of the ball screw nut 5 is selected and reciprocally and independently coupled. That is, there are two working modes: a moving body ball screw drive type in the case of the tooth profile clutches 7 and 9, and a moving body fixed type in the case of the tooth shape clutches 3 and 4.

In the case of a movable table ball screw drive in which the tooth-shaped clutch D9 is coupled to the ball screw nut 5, the movable table 6 is screwed when the ball screw 1 is rotated by the coupling with the ball screw nut by the rotation of the ball screw 1 with the spline. It is moved according to the pitch. This is the same as the case where the conventional nut and the moving body are fixed. The movable table 6 is driven by the rotation of only the ball screw 1.

The spline groove 30 processed into the splined ball screw 1, the groove depth of which is about 10% of the diameter of the ball screw sphere 29, and the tooth-shaped clutch A 3 and the ball screw nut 5 that are fitted to the ball screw 1. Since the relative distance between the ball screw 1 and the ball screw nut 5 is fixed, the ball screw nut 5 is located at one location on the axis of the ball screw. The ball screw 1 is rotated integrally with the ball screw 1. In this case, the movable table 6 is fixed at the same place. In addition, the rotation output synchronized with the rotation of the ball screw 1 is transmitted to the outside of the moving table 6 via the bevel gear on the outer periphery of the tooth clutch C7 coupled to the ball screw nut 5 and the rotation derivation / entry bevel pinion gear 22. It can be taken out via the rotary input / output shaft 23.

In order to place the moving body in a neutral state, it must be isolated from external rotational vibrations. Therefore, in this proposal, as shown in FIG. 1, the vibration from the entire apparatus frame via the drive shaft rotation direction 12 from the outside or the ball screw rotation drive bearing 13 is blocked by the electromagnetic clutch coupling portion 10 by the ball screw drive shaft 11. ing. In conjunction with the lever position B19, the electromagnetic clutch switch 16 opens the fixed electromagnetic winding 14 and the electromagnetic clutch winding power source 15.

The switching between the tooth-shaped clutch A3 and the tooth-shaped clutch D9 for switching the work mode is performed when the ball screw 1 is driven or when it is neutrally stationary. In order to facilitate the engagement of the tooth-shaped clutch, a sliding conical portion 4a shown in detail in FIG. 3 tooth-shaped clutch coupling portion is arranged inside the tooth-shaped clutches B4 and C7, and the ball retainer 3a is placed inside the opposing tooth-shaped clutches A3 and D9. The tooth-shaped coupling guide balls 34 held by the two teeth are engaged and the tooth-shaped clutch portion rotates relatively. When the tooth-shaped clutch portion approaches, the rotational speeds of the conical portion and the guide ball are synchronized with each other. Further, when the top of the tooth-shaped clutch trapezoidal tooth portion 32 approaches, the tooth-top portions are prevented from coming into contact with each other by the comb-shaped guide ball groove 33 shown in FIG. 4, and the clutch tooth shapes are coupled to each other. Thus, the structure of the sliding cone portion 4a in which the comb-shaped guide ball groove 33 is engraved in the tooth-shaped clutches B4 and C7 having the trapezoidal tooth profile portion 32 facilitates the synchronous coupling operation.

By adopting the clutch type coupling shown in FIG. 1 as described above, the drive shaft for movement control of the moving table is reduced to one ball screw, the control becomes simple, and conventionally, an independent drive shaft is required separately. The moving platform control system was simplified.

As an embodiment, a small lathe, a milling machine, etc. are considered to be in the application range.
A device and a form for preventing dust from entering the ball screw and the clutch are desired. This plan will be effective when a special high-speed movement is not required for the ball screw drive platform. However, it is considered effective for usage forms that require precise control.

The simple system for driving the ball screw according to the present invention can be applied to a practical small-scale machine tool configured with as few parts as possible, such as a small precision lathe.

Application is possible when it is necessary to simplify the operation of the moving table in a general ball screw drive system.

Clutch coupling ball screw Ball screw details with spline Tooth profile clutch coupling details Fig. 3-1, Tooth profile clutch released Fig. 3-2, Tooth profile clutch coupled state Comb guide

Explanation of symbols

1. Ball screw (with spline groove on outer diameter)
2. 2. Direction of ball screw rotation Toothed clutch A (with spline groove on inner diameter)
3a. Ball retainer4. Tooth profile clutch B (fixed to ball screw nut)
4a. 4. sliding cone part Ball screw nut 6. 6. Moving table Tooth-shaped clutch C (with bevel gear fixed to the ball screw nut on the outer diameter)
8). 8. Guide tube with moving table side spline Tooth-shaped clutch D (It has a spline groove on the outer diameter part and fits on the movable table side guide cylinder)
10. 10. electromagnetic clutch coupling part Ball screw drive shaft 12. 12. Drive shaft rotation direction Ball screw rotary drive bearing 14. Fixed electromagnetic winding 15. Power supply for electromagnetic clutch winding 16. Electromagnetic clutch switch 17. Clutch D side switching lever 18. Lever position A (Clutch D side connection)
19. Lever position B (neutral open position)
20. Lever position C (clutch A side coupling)
21. Lever connecting rod 22. Rotation derivation / entry bevel pinion gear 23. Rotation input / output shaft 24. Clutch A side switching lever (linked with 17)
25. Lever position A (linked with 18)
26. Lever position B (linked with 19)
27. Lever position C (linked with 20)
28. Tooth-shaped clutch coupling part 29. Ball screw sphere (diameter Rmm)
30. Spline groove 31. Spline groove depth (~ 0.1 × R)
32. Tooth profile clutch trapezoidal tooth profile 33. Comb guide ball groove 34. Tooth profile guide ball

Claims (3)

In a ball screw with a spline, a ball screw device having a structure for driving a moving body by securing a coupling with a ball screw using a toothed clutch on the front and rear of a coupling axis of a ball screw nut coupled to the ball screw. A ball screw coupling structure in which the ball screw nut and the moving body are coupled via a bearing, and the rotational force of the ball screw can be extracted to the outside of the moving body via a toothed clutch and a gear coupling. A clutch structure having a comb-shaped guide ball groove and a tooth-shaped coupling guide ball fitted therein to facilitate coupling of a tooth-shaped clutch that slides on a ball screw shaft coupled to a ball screw nut.

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