JP2004108523A - Lubricating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubricating device inhibiting the leakage of a lubricant with a simple structure. <P>SOLUTION: This lubricating device comprising a driving means having a ball screw 5a and a ball screw nut, a pump 7 is mounted on one end of the ball screw shaft 5 for supplying the lubricant to a sliding part, and a circulating passage is formed for recovering the lubricant supplied to the sliding part and resupplying the same. The pump 7 is composed of a cylinder 14 externally fitted to the ball screw 5a and meshed with the ball screw 5a, a reducer 13 for reducing a speed of the movement of the cylinder 14 in the ball screw shaft 5 direction, and a piston body 11 mounted on the ball screw shaft 5 in the cylinder 14, and the rotating motion of the ball screw 5a is converted into the linear motion of the cylinder 14 to supply the lubricant by the relative motion of the cylinder 14 and the piston body 11. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lubricating device that supplies lubricating oil to a sliding portion of a machine having a moving body that slides by a driving unit having a ball screw and a ball screw nut.
[0002]
[Prior art]
In a machine tool, for example, a moving body such as a table or a column which moves on a support such as a bed via a sliding or rolling element is provided, and a portion accompanying these relative motions smoothly operates. Lubricating oil is supplied for the purpose. Conventionally, such a lubricating oil device has a simple configuration in which there is only a one-way path for supplying the lubricating oil device.
In this case, the lubricating oil used for lubrication is collected in a tank or the like after passing through a toy, an oil pan, etc., and is then wasted, so that the amount of lubricating oil used is large and wasteful. It was unnecessarily dirty. Further, in machine tools, cutting fluid is often used during machining, but lubricating oil has been mixed into this cutting fluid. When lubricating oil is mixed into the cutting fluid, the life of the cutting fluid is significantly shortened, so that the cost of the cutting fluid is increased, or the cost is increased, such as adding equipment for removing the lubricating oil from the cutting fluid.
Therefore, a circulation type in which a recovery path is provided to circulate lubricating oil (for example, see Patent Document 1) has been used.
[0003]
[Patent Document 1]
Japanese Utility Model Publication No. 62-11550
[Problems to be solved by the invention]
However, even in the case of a circulation type having a recovery path, a part of the supplied lubricating oil leaks out from, for example, both ends of the bearing portion or a slight gap around the bearing portion and flows out. It was collected in tanks and the like using toys and oil pans and was turned into waste oil. Thus, the leakage of the lubricating oil still occurred, and the machine itself was unnecessarily soiled. Moreover, in the case of machine tools, it has been mixed into the cutting fluid.
Therefore, the drive and operation time of the pump that supplies lubricating oil by providing a timer are arbitrarily set, and control is performed so as to operate at a time interval according to the operation time of the machine tool, thereby supplying waste lubricating oil as much as possible. Some devices were devised not to do so, but the leakage of the lubricating oil still occurred, and the structure of the lubricating device was complicated.
[0005]
In view of the above problems, it is an object of the present invention to provide a lubricating device that has a simple structure and that can suppress leakage of lubricating oil.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 includes a motor, a ball screw, and a ball screw provided on a ball screw shaft including one end of the ball screw. A pump is provided for supplying the lubricating oil to the sliding portion of the moving body using the rotational motion as a drive source, and a circulation path for collecting the lubricating oil supplied to the sliding portion and again providing the lubricating oil for the sliding portion is provided. It is characterized by having.
[0007]
According to a second aspect of the present invention, in the first aspect of the present invention, the pump comprises: a cylinder externally fitted to the ball screw shaft; a speed reduction device for reducing the movement of the cylinder in the ball screw axis direction; The cylinder has a nut portion meshed with a ball screw, and a cylinder space that enables relative movement of the piston body within the cylinder and is connected to a tank of lubricating oil, The rotation of the ball screw causes the cylinder to move linearly, and the piston body is moved relative to the cylinder in the cylinder space to supply lubricating oil.
[0008]
The invention of claim 3 is characterized in that, in the invention of claim 1 or 2, an adsorbing member for adsorbing the lubricating oil is provided at the lubricating oil discharge portion of the moving body.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic view showing an example of a sliding portion of a machine tool provided with a lubricating device according to the present invention, wherein 1 is a bed supporting a moving body or the like, 2 is a guide rail, and 3 is sliding on the bed. A moving body 4, a motor as a driving source of the moving body 3, a ball screw shaft 5 having a ball screw 5a, a rotary joint device 6, a pump 7 for supplying lubricating oil, and a ball screw shaft 5 and two guides The rails are arranged in parallel with the ball screw shaft 5 arranged at the center.
[0010]
The moving body 3 has a ball screw nut 9 which is fitted to the ball screw 5a and fitted to the ball screw 5a at substantially the center of the lower part, and holds the guide rail 2 at the four corners of the bottom corresponding to the guide rail 2. A guide slider 10 slidable arbitrarily is provided. One end of the ball screw shaft 5 is connected to the motor 4, and the ball screw 5 a is rotated by the motor 4 so that the ball screw nut 9 moves linearly, and the moving body 3 slides on the bed 1. At this time, the guide slider 10 also slides on the guide rail 2.
[0011]
FIG. 2 is a cross-sectional explanatory view of the pump 7 and the rotary joint device 6. The pump 7 has a reduction gear 13 provided adjacent to the ball screw shaft 5, and a cylindrical shape that is fitted over the ball screw 5 a and meshes with the ball screw 5 a. , And the piston body 11 formed on the ball screw shaft 5.
The speed reducer 13 is formed in two stages on a first gear 12 fixed to one end of the ball screw shaft 5 so as to have the same rotation axis as the ball screw shaft 5 and a shaft 13 c parallel to the ball screw shaft 5. A second gear 13a having a large diameter and a third gear 13b having a small diameter are provided, and one end of a shaft 13c is projected and fixed to a fixing means 15 provided on the bed. The second gear 13a meshes with the first gear 12, and the third gear 13b meshes with a fourth gear 14a provided on the cylinder 14.
[0012]
The cylinder 14 is formed in a cylindrical shape, and a fourth gear 14a is formed in the shape of a flange on the outer periphery of one end as the same rotation axis as the cylinder 14, and the inside of the cylinder space 17 is formed into a cylindrical shape with a ball screw engagement portion 14b. Is formed.
At the end of the ball screw 5 a of the ball screw shaft 5 corresponding to the cylinder space 17 of the ball screw shaft 5, a piston body 11 is formed to protrude outward in a flange shape. The piston body 11 is formed to have the same diameter as the cylinder space 17, and is formed to act as a piston in the cylinder 14. Since the cylinder 14 is meshed with the ball screw 5a, if the cylinder 14 is turned by itself, it moves in the axial direction while rotating around the ball screw 5a.
[0013]
On the other hand, the ball screw shaft 5 near the piston body 11 located in the cylinder space 17 has a pump-side supply hole 19a for supplying lubricating oil to the cylinder space 17 and a pump-side discharge hole 20a for discharging lubricating oil from the moving space 17. Is provided, and a lubricating oil filling space 17 a is formed in one cylinder space 17 divided by the piston body 11. These two holes 19a, 20a are connected to the joint-side supply hole 19b and the joint-side discharge hole 20b formed at positions corresponding to the end of the ball screw shaft 5 in the rotary joint device 6 via communication holes 19, 20. ing.
The rotary joint device 6 has ring-shaped lubricating oil passages 21 and 22 corresponding to the joint-side supply hole 19b and the joint-side discharge hole 20b formed in the ball screw shaft 5. The lubricating oil passages 21 and 22 are respectively connected to lubricating oil pipes (not shown) formed outside the rotary joint device, and swivel through the lubricating oil passages 21 and 22 and the communication holes 19 and 20. The lubricating oil is supplied to and discharged from the pump on the ball screw shaft, and the lubricating oil is supplied to each sliding portion and circulated.
X and Y in FIG. 2 indicate the rotation direction and the movement direction of the cylinder 14 that moves in accordance with the rotation, and 23 is a fixing means provided with a rolling bearing that supports one end of the ball screw shaft 5.
[0014]
FIG. 3 shows a lubricating oil circuit of the lubricating apparatus of FIG. 1, 24 is a check valve for preventing backflow of lubricating oil, 25 is a tank for storing lubricating oil, 26 is a filter for removing dirt, and 27 is each 4 shows a lubricating oil flow path for supplying lubricating oil to a sliding portion. As shown in the figure, the flow path 27 is formed so as to supply and circulate the lubricating oil discharged from the pump 7 to the ball screw nut 9 and the four guide sliders 10 in parallel, and the tank 25 is used to circulate the lubricating oil. It is provided in order to eliminate the resistance of the lubricating oil in the piping forming the flow path from the opposite side during the supply operation and the suction operation, and is provided in the middle of the return piping passing through the bearing portion.
[0015]
Hereinafter, the operation of the lubricating oil supply pump and the lubricating device having the above configuration will be described. When the ball screw 5a is rotated by the motor 4, the cylinder 14 is rotated by the reduction gear 13 in the same direction as the ball screw 5a at a lower speed than the ball screw 5a. Due to this rotation difference, the cylinder 14 performs a linear movement of a smaller distance than the moving distance of the ball screw nut 9 due to the rotation of the ball screw 5a. Therefore, even if the ball screw 5a generates a long moving stroke like the moving body 3, the cylinder 14 moves with a short stroke, and the cylinder 14 in which the piston body 11 is disposed can perform a good linear motion.
When the rotation of the ball screw 5a changes between normal rotation and reverse rotation, the cylinder 14 reciprocates in the axial direction with respect to the piston body 11, and the volume of the lubricating oil filling space 17a in the cylinder space 17 changes periodically. Circulate the lubricating oil.
[0016]
More specifically, when the ball screw 5a rotates forward (for example, rotates in the X direction shown in FIG. 2), the cylinder 14 moves rightward in the figure. Then, the piston body 11 moves to the left relative to the cylinder 14 and the lubricating oil filling space 17a expands, and the check valve 24 provided in the flow path 27 acts on the pump 25 to supply the pump-side supply hole 19a from the tank 25. The lubricating oil is supplied into the cylinder 14 via the.
Next, when the ball screw 5a rotates in the reverse direction (for example, rotates in the Y direction shown in FIG. 2), the cylinder 14 moves to the left in the figure. Then, the lubricating oil filling space 17a contracts contrary to the above-described normal rotation, and does not flow out toward the tank 25 by the action of the check valve 24, but flows into the other flow path through the pump-side discharge hole 20a. The lubricating oil inside is released.
In this way, the pump 7 acts as a lubricating oil circulation pump, and circulates the lubricating oil in one direction to circulate the flow path, and supplies to the sliding portion, and collects and supplies again.
[0017]
In this way, the lubricating oil once sent out is collected, so that waste such as dripping and discharging can be prevented, and if a filter is interposed, dirt can be removed and reused, and the lubricating oil can be used efficiently. it can.
In addition, since the driving force of the pump for supplying the lubricating oil is obtained from the rotation of the ball screw that slides the moving body, no separate pump driving source is required, and a part of the ball screw is used as the piston of the pump for supplying the lubricating oil. Therefore, the number of pump members can be reduced, and the apparatus can be simplified.
Also, since the pump operates and supplies the lubricating oil only when the moving body is sliding, the lubricating oil can be supplied to the sliding parts such as the bearing part when necessary without separately providing a timer or the like. Since no extra lubricating oil is supplied and the driving force required for circulation is obtained from the movement of the structure on the machine, it is possible to reduce the electric energy required to drive only the conventional lubrication device.
[0018]
4A and 4B show a configuration of the guide slider 10 of FIG. 1, wherein FIG. 4A is a sectional view taken along line AA of FIG. 1, and FIG. 4B is a sectional view taken along line BB of FIG. As shown in the drawing, a lubricating oil suction member 28 is incorporated in the guide rail 2 engaging portion of the guide slider 10, and the lubricating oil discharge port 29 of the guide slider 10 is aligned with the lubricating oil discharge port 29 as shown in FIG. The lubricating oil is provided at the front and rear ends, and is supplied to the sliding surface via the lubricating oil absorbing member 28. The lubricating oil absorbing member 28 is preferably made of, for example, felt.
Reference numeral 30 denotes a lubricating oil sump for sending lubricating oil to the lubricating oil discharge port 29. The two lubricating oil sumps 30, 30 are connected via the internal flow passage 10a and connected to the external flow passage 27, respectively. ing.
By arranging the lubricating oil adsorbing member at the lubricating oil supply port of the sliding portion as described above, the lubricating oil at the sliding portion is adsorbed, so that leakage of the lubricating oil to the outside can be suppressed and the oil can be circulated without waste. it can. Therefore, the contamination of the machine by the lubricating oil can be minimized.
[0019]
In the above embodiment, the ball screw nut and the lubricating device for lubricating the sliding portion of the guide slider have been described. However, the sliding portion may be formed in another form, for example, a ball, needle, or a sliding portion via a rolling bearing of a roller. This can be easily applied by providing a pump using the rotational motion of the ball screw as a drive source.
Further, as shown in FIG. 5, in addition to the structure shown in FIG. 4, the guide slider 10 may be provided with a seal 31 formed of a resin such as rubber on the outside of the lubricating oil absorbing member 28. As a result, the effect of further preventing leakage of the lubricating oil can be achieved, and the adhesion of chips to the lubricating oil adsorbing member 28 formed of felt or the like can be suppressed.
[0020]
【The invention's effect】
As described above in detail, according to the first aspect of the present invention, since the driving force of the pump for supplying the lubricating oil is obtained from the rotation of the ball screw that slides the moving body, a pump driving source, a timer, and the like are separately provided. The lubricating oil can be supplied to the sliding portion such as the bearing portion when necessary with a simple structure.
Also, the pump operates and supplies the lubricating oil only when the moving body is sliding, so that no extra lubricating oil is supplied, and the driving force required for circulation is reduced by the movement of the structure on the machine. By obtaining from the operation, it is also possible to reduce the electric energy that drives only the conventional lubricating device.
[0021]
According to the second aspect of the present invention, in addition to the effect of the first aspect, a part of the ball screw is used as a piston of a pump for supplying lubricating oil, so that the number of pump members can be reduced and the configuration can be simplified. Can be.
According to the third aspect of the invention, in addition to the effects of the first or second aspect, since the lubricating oil at the sliding portion is adsorbed, the leakage of the lubricating oil to the outside can be suppressed and the oil can be circulated without waste. As a result, the contamination of the machine by the leaked lubricating oil can be minimized.
[Brief description of the drawings]
FIG. 1 is a schematic view showing an example of a sliding portion of a machine tool provided with a lubrication device according to the present invention.
FIG. 2 is an explanatory sectional view of the pump and the rotary joint device of FIG. 1;
FIG. 3 is a lubricating oil circuit diagram of FIG. 1;
FIGS. 4A and 4B are cross-sectional views of the guide slider of FIG. 1, wherein FIG. 4A is a cross-sectional view taken along line AA, and FIG.
5A and 5B show another example of a cross-sectional view of the guide slider of FIG. 1, wherein FIG. 5A is a cross-sectional view taken along line AA, and FIG.
[Explanation of symbols]
1. bed, 2. guide rail, 3. moving body, 4. motor, 5. ball screw shaft, 5a ball screw, 6. rotary joint device, 7. pump, 9. ball screw nut 10, guide slider, 13 speed reducer, 14 cylinder, 16 piston body, 25 tank, 27 flow path, 28 lubricating oil absorbing member, 29 lubricating oil discharge port , 31. Seal.

Claims (3)

In a machine having a moving body that slides by a motor and a driving means having a ball screw and a ball screw nut, lubricating oil is slid on the ball screw shaft including one end of the ball screw by using the rotational motion of the ball screw as a driving source. A lubricating apparatus comprising: a pump for supplying a moving part; and a circulation path for collecting the lubricating oil supplied to the sliding part and providing the lubricating oil to the sliding part again. The pump includes a cylinder externally fitted to the ball screw shaft, a reduction gear for reducing the movement of the cylinder in the ball screw axis direction, and a piston body provided around the ball screw shaft located in the cylinder, and the cylinder includes: A nut portion meshing with the ball screw and a cylinder space connected to a lubricating oil tank, enabling relative movement of the piston body in the cylinder,
The lubricating apparatus according to claim 1, wherein the cylinder is linearly moved by the rotational movement of the ball screw, and the piston body is moved relative to the cylinder in the cylinder space to supply lubricating oil. 3. The lubricating device according to claim 1, wherein an adsorbing member for adsorbing the lubricating oil is provided at a lubricating oil discharge portion of the moving body.

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