TWI525273B - Ball screw - Google Patents

Description

Ball lead screw

The present disclosure relates to a ball lead screw. More specifically, the present disclosure is a ball lead screw having a cooling function.

With the rapid advancement of science and technology, the technology of today's machine tools is developing toward high speed and high precision. The most important transmission component of the machine tool is the ball lead screw. The ball guide screw mainly includes a screw, a nut and a ball. The ball lead screw and the ball are in contact with each other by the point contact between the screw and the nut to obtain power. However, the high speed and high precision are mutually influential, and if high speed is desired, it is inevitable A large frictional heat is generated between the screw, the nut and the ball of the ball lead screw, and the friction heat causes the screw to expand and deform, so that the positioning accuracy changes, and the predetermined position is not reached, and the high precision cannot be achieved. aims.

Therefore, if you want to achieve both high speed and high precision, you can install a cooling water jacket in the structure of the nut, and use the water in the cooling water jacket to heat the heat generated by the ball screw at high speed. The structure of the nut is taken away, but this method must have more processing and cannot directly cool the heat source, resulting in an increase in cost, and the high speed rotation of the ball lead screw easily causes the water in the cooling water jacket to overflow, and further, When the cooling water jacket is installed in the nut structure, the overall installation space is increased, resulting in inconvenience in use.

However, how to overcome the problems of the prior art is an important issue.

The present disclosure discloses a ball lead screw, which comprises: a screw, an outer ring thereof a first thread on the surface; a nut having an inner ring surface having a second thread corresponding to the first thread, and the nut being sleeved by the plurality of balls housed in the first thread and the second thread a surface of the outer ring of the screw; and at least one fluid passage formed in the nut, the fluid passage having at least one inflow end and at least a first-stage end, the outflow end being located on the inner ring surface of the nut At the second thread, the inflow end is located on a side or a top surface of the nut.

According to the above, the ball guide screw of the present disclosure transmits fluid to the fluid passage by the fluid supply device, and utilizes a fluid pressure regulating device to provide a better fluid pressure, and the fluid finally flows to the screw to Cooling the screw to improve the positioning accuracy of the ball lead screw; further, the present disclosure does not have the problem of limited cooling effect of the prior art, and there is no problem of cooling water overflow; further, the fluid passage of the present disclosure flows out. The end is located at the second thread of the inner ring surface of the nut, that is, where the ball does not pass (ie, the thread peak), so that damage to the second thread during the processing of the flow path can be avoided.

The embodiments of the present disclosure are described below by way of specific embodiments, and those skilled in the art can readily appreciate the other advantages and functions of the present disclosure.

It is to be understood that the structure, the proportions, the size and the like of the present invention are only used to clarify the disclosure of the specification for the understanding and reading of those skilled in the art, and are not intended to limit the disclosure. Limited Conditions, so it is not technically meaningful. Any modification of the structure, change of the proportional relationship or adjustment of the size should remain in this disclosure without affecting the effects and the objectives that can be achieved by this disclosure. The technical content revealed can be covered. In the meantime, the terms "upper", "one" and "two" as used in this specification are for convenience of description only, and are not intended to limit the scope of the disclosure, the relative relationship may be changed or Adjustments, if there is no material change in the content of the technology, are also considered to be the scope of implementation of this disclosure.

First embodiment

As shown in FIG. 1A, which is a perspective view of a first embodiment of the ball lead screw of the present disclosure, the ball guide screw of the present disclosure includes: a screw 10, a nut 12, a fluid supply device 14, a communication tube 16, and a fluid. Pressure regulating device 18.

1B is a schematic cross-sectional view along section line AA of FIG. 1A. The outer ring surface 10a of the screw 10 has a first thread 102 thereon, and the first thread 102 corresponds to the inner ring surface of the nut 12. The second thread 122 of the 12a is additionally sleeved on the outer ring surface 10a of the screw 10 by a plurality of balls 104 accommodated between the first thread 102 and the second thread 122.

In the ball lead screw of the present disclosure, at least one fluid passage 124 is formed in the nut 12, and the fluid passage 124 has at least one inflow end 124a and at least a first-stage end 124b, and the outflow end 124b is located in the screw The inner ring surface 12a of the cap 12 is not at the second thread 122, and the inflow end 124a is located on the side of the nut 12. In the embodiment, the fluid is The passage 124 is composed of a radial flow passage 1241 and an axial flow passage 1242 having an inflow end 124a and three outflow ends 124b, and the inflow end 124a is located on the side of the nut 12.

The fluid supply device 14 is connected to the inflow end 124a of the fluid passage 124, and the fluid supply device 14 can be a liquid gas mixer or a mist supply. For example, the fluid supply device 14 is an oil and gas mixture. After the lubricating oil and the gas are mixed in the fluid supply device 14, a lubricating oil mist having a large heat transfer coefficient is generated, and the oil mist flows out from the respective outflow ends 124b to contact the screw 10 through the fluid passage 124, The heat energy of the screw 10 is taken away, the temperature of the screw 10 is lowered, and the lubricating effect is provided. In addition, the fluid supply device 14 and the inflow end 124a of the nut 12 can be connected by the connecting pipe 16, and A fluid pressure regulating device 18 is disposed between the fluid supply device 14 and the inflow end 124a of the nut 12, and the fluid pressure of the oil mist is controlled by the fluid pressure regulating device 18.

Second embodiment

As shown in FIG. 2A, it is a perspective view of a second embodiment of the ball lead screw of the present disclosure. Referring to FIG. 2B, it is a schematic cross-sectional view along the line BB of FIG. 2A. The difference in the first embodiment is mainly that the fluid passage 124 has only a radial shape, and the inflow end 124a is located on the top surface of the nut 12, and the number of the fluid passage 124, the fluid pressure regulating device 18 and the communication tube 16 is For example, in the embodiment, there are three connecting tubes 16, three of the fluid passages 124 and three of the fluid pressure regulating devices 18, and each of the fluid pressure regulating devices 18 is correspondingly disposed on each of the communicating tubes 16, and each of the tubes a communication pipe 16 is connected to each of the fluid passages 124, and each of the fluid pressure regulating devices The 18 series corresponds to each of the fluid passages 124, and the fluid passages 124 are not in communication with each other. Therefore, each of the fluid pressure regulating devices 18 can individually adjust the fluid pressure in the corresponding fluid passage 124.

As shown in Fig. 3, it is a relationship diagram between the oil mist pressure and the screw temperature. When the pressure of the oil mist is 1 atm, the maximum temperature of the screw is 44.67 ° C; when the pressure of the oil mist is 2 atm, The maximum temperature of the screw is 23.61 ° C; when the pressure of the oil mist is 3 atm, the maximum temperature of the screw is 22.76 ° C. From the above simulation results, it is known that the supply of the oil mist can achieve the effect of cooling.

In addition, it was confirmed after the experiment that when the room temperature was 20 ° C and rapid feed (30 m / min) was performed, the positioning precision of the ball lead screw of the present disclosure was up to 3 μm / 3 m, and generally The ball lead screw has a positioning accuracy of only 880 μm / 3 m.

In summary, the ball guide screw of the present disclosure transmits fluid to the fluid passage by the fluid supply device, and utilizes a fluid pressure regulating device to provide a better fluid pressure, and the fluid finally flows to the screw for cooling. The screw further improves the positioning accuracy of the ball lead screw; moreover, the present disclosure does not have the problem of limited cooling effect of the prior art, and there is no problem of cooling water overflow; further, the outflow end of the fluid passage of the present disclosure It is located at the second thread of the inner ring surface of the nut, that is, where the ball does not pass (ie, the thread peak), so that damage to the second thread during the processing of the flow path can be avoided.

The above embodiments are merely illustrative of the effects of the disclosure, and are not intended to limit the disclosure, and anyone skilled in the art can Modifications and changes to the above-described embodiments are made in the spirit and scope of the disclosure. In addition, the number of components in the above-described embodiments is merely illustrative and is not intended to limit the disclosure. Therefore, the scope of protection of the present disclosure should be as set forth in the scope of the patent application described later.

10‧‧‧ screw

10a‧‧‧ outer ring surface

102‧‧‧First thread

104‧‧‧ balls

12‧‧‧ Nuts

12a‧‧‧ Inner ring surface

122‧‧‧second thread

124a‧‧‧Incoming end

124b‧‧‧ outflow

124‧‧‧ fluid passage

1241‧‧‧radial runner

1242‧‧‧Axial runner

14‧‧‧Fluid supply device

16‧‧‧Connected pipe

18‧‧‧Fluid pressure regulator

A-A, B-B‧‧‧ hatching

1A is a perspective view of a first embodiment of the ball lead screw of the present disclosure; FIG. 1B is a schematic cross-sectional view taken along line AA of FIG. 1A; FIG. 2A is a ball lead screw of the present disclosure. 2D is a schematic cross-sectional view along section line BB of FIG. 2A; and FIG. 3 is a relationship diagram of numerical simulation of oil mist pressure and screw temperature.

10‧‧‧ screw

10a‧‧‧ outer ring surface

102‧‧‧First thread

104‧‧‧ balls

12‧‧‧ Nuts

12a‧‧‧ Inner ring surface

122‧‧‧second thread

124a‧‧‧Incoming end

124b‧‧‧ outflow

124‧‧‧ fluid passage

1241‧‧‧radial runner

1242‧‧‧Axial runner

14‧‧‧Fluid supply device

16‧‧‧Connected pipe

18‧‧‧Fluid pressure regulator

Claims (9)

A ball lead screw includes: a screw having a first thread on an outer ring surface; a nut having an inner ring surface having a second thread corresponding to the first thread, and the nut is accommodated by the plurality a thread and a ball in the second thread are sleeved on the outer ring surface of the screw; at least one fluid passage is formed in the nut, the fluid passage has at least one inflow end and at least a first-stage end, the outflow The end is located at the second thread of the inner ring surface of the nut, the inflow end is located at a side or a top surface of the nut; the fluid supply device is configured to generate a lubricating oil mist; and the fluid pressure regulating device Provided between the fluid supply device and the inflow end to adjust the pressure of the oil mist, wherein when the pressure of the oil mist is greater than 1 atmosphere, the maximum temperature of the screw is lowered to achieve the cooling effect of the screw . The ball lead screw of claim 1, wherein the fluid supply device is a liquid gas mixer. The ball lead screw of claim 1, wherein the fluid supply device is a mist supply. The ball lead screw according to claim 1, wherein the number of the fluid passage and the fluid pressure regulating device is plural, each of the fluid pressure regulating devices corresponding to each of the fluid passages, and the fluid passages are mutually Not connected. a ball lead screw according to claim 2, wherein The liquid gas mixer is an oil and gas mixer. The ball lead screw of claim 5, wherein the oil and gas mixer is for mixing a lubricating oil with a gas. The ball lead screw of claim 1, wherein the fluid passage is composed of a radial flow passage and an axial flow passage. The ball lead screw of claim 1, wherein the fluid passage is a radial flow passage. The ball lead screw according to claim 4, further comprising a plurality of connecting pipes, wherein each of the fluid supply device and the inflow end of each nut are connected by each of the connecting pipes, and each of the fluid regulating devices Corresponding to each of the connecting tubes.