KR101005472B1 - Method of processing the interior of Nut for ball screw - Google Patents

Abstract

The present invention relates to an internal processing method of a ball screw nut which linearly reciprocates in the longitudinal direction of a screw by rotation of a circulating ball and the screw.

The internal processing method of the ball screw nut according to the present invention, the semi-finished product preparation step (S100) for preparing a semi-finished semi-finished product in the interior, and the circulation path for processing a part of the circulation path 110 of the ball (Ball) The primary machining step (S200), the circulation path secondary processing step of forming a spiral on the inner peripheral surface of the semi-finished product of the circulation path 110 (S300), and the semi-finished product formed of the spiral chuck 210 of the lathe device (200). Screw step 112 having a semicircular cross section by matching the spiral with the setting step (S400) and the tab 242 installed on the tab carriage 240 for linear reciprocating motion and then rotating the chuck 210. The circulation path tertiary processing step (S500) to form a) and the separation step (S600) for separating the finished product passed through the circulation path tertiary processing step (S500) from the chuck with the tab 242, and the Characterized in that the finished product recovery step (S700) for separating the finished product from the tab 242. According to this processing method, there is an advantage that the defective rate is reduced and the productivity is improved.

Ball screw, nut, ball, processing method

Description

Method of processing the interior of Nut for ball screw}

1 is a perspective view showing the front appearance of a nut for a ball screw manufactured according to an embodiment of the present invention.

Figure 2 is a perspective view showing the rear appearance of the ball screw nut manufactured according to an embodiment of the present invention.

3 is a cross-sectional view taken along line II ′ of FIG. 1 showing an internal configuration of a nut for a ball screw manufactured according to an embodiment of the present invention.

Figure 4 is a perspective view showing the configuration of a processing apparatus used in the internal processing method of the ball screw nut according to the present invention.

Figure 5 is a perspective view showing in detail the main portion of the processing apparatus used in the internal processing method of the ball screw nut according to the present invention.

Figure 6 is a flow chart showing an internal processing method of a ball screw nut according to the present invention.

Figure 7 is a cross-sectional view showing the internal configuration of the semi-finished product in the internal processing method of the ball screw nut according to the present invention.

Figure 8 is a cross-sectional view showing the internal configuration of the semi-finished product of the circulation path primary processing step in the internal processing method of the ball screw nut according to the present invention.

Figure 9 is a cross-sectional view showing the internal configuration of the semi-finished product of the circulation path secondary processing step in the internal processing method of the ball screw nut according to the present invention.

Explanation of symbols on the main parts of the drawings

100.Nut 110.Circulation Path

112. Nasal valley 114. Straight hole

116. Switching guide groove 200. Lathe

210. Chuck 220. Mounting Hole

222. Elastic Slit 240. Tap Feeder

242. Tabs 244. Tab Mounting Section

246.Rail S100. Semi-finished product preparation stage

S200. Circular path primary processing step S300. Circulation path secondary processing stage

S400. Setting step S500. Circulation Path 3rd Processing Step

S600. Separation step S700. Finished product recovery stage

The present invention relates to an internal processing method of a nut for a ball screw, and more particularly, to an internal processing method of a nut for a ball screw in which a screw bone of a nut forming a circulation path of a ball is formed more precisely and easily. It is about.

In general, a ball screw is a machine in which a screw bone is machined on the outer circumferential surface (Screw.) And a nut (thread) on the inner circumferential surface is operated by the rolling motion of the ball. As a component, it is configured such that when the one of the nut and the screw is fixed and the other rotates, this rotational movement is converted into a linear movement.

Therefore, the ball screw has been widely applied to a numerical control machine tool, a mechanical control device of an aircraft, or other feeding mechanisms of machines and devices requiring precision.

The ball screw has a semicircular cross section of the screw bone formed on the inner circumferential surface of the nut and the outer circumferential surface of the screw (Screw), respectively, and the semicircular cross section forms a circular cross section when the screw is inserted into the nut to form a spiral passage. do.

And the ball (Ball) is fitted into the spiral passage formed by the combination of the nut and the screw, the ball is rolling by rolling along the passage it is possible to reduce the friction during the rotation of the nut.

The screw bone formed on the outer circumferential surface of the screw can be easily processed using a lathe, but the screw bone formed on the inner circumferential surface of the nut is difficult to lathe in position, and even if the lathe is processed, the size of the tap is gradually increased to increase the number of times. There is a problem that the productivity is lowered because it is processed over.

In addition, as the tapping is performed a plurality of times, there is a problem that the defective rate is lowered.

Therefore, in general, the screw bone machining of the inner circumferential surface of the nut is required to be finished by using NC (numerical control) factory value after drilling and tapping.

In addition, even if the NC processes the screw bone on the inner peripheral surface of the nut with a fixed number using a factory value, it is not preferable because the defect is often caused by the process of shifting from the position of the previously processed tap to cause the nut itself.

An object of the present invention for solving the problems as described above, the installation of the mounting tool manufactured separately on the chuck of the shelf and the inside of the ball screw nut to enable screw bone processing by using a tab in a state fixed to the semi-finished product in the mounting tool It is to provide a processing method.

Another object of the present invention is to further provide a separate tab feeder for the tab processing of the semi-finished product on one side of the shelf, and to minimize the tensile force applied to the semi-finished product by minimizing the tensile force applied to the semi-finished product when the thread bone processing It is an object of the present invention to provide a method of internally processing a nut for a ball screw in which the accuracy is improved.

The internal processing method of the ball screw nut according to the present invention includes a semi-finished product preparation step of preparing a cylindrical semi-finished product with an inner hole, a circulation path primary processing step of processing a part of a circulation path of a ball, and The second step of the circulation path to form a spiral on the inner peripheral surface of the semi-finished product of the circulation path, the setting step of fixing the semi-finished product formed on the spiral to the chuck (Chuck) of the lathe device, and a tab installed on the tab reciprocating linear movement Matching the spirals and rotating the chuck to form a screw bone having a semicircular cross section, the circulation path tertiary processing step, and the separation step of separating the finished product undergoing the circulation path tertiary processing step from the chuck with a tab And, characterized in that consisting of the finished product recovery step of separating the finished product from the tab.

The first step of the circulation path processing step, the guide groove for switching the spiral motion of the ball (Ball) to a linear motion, and the linear guide hole for guiding the ball in the direction of the linear movement along the conversion guide groove in a straight direction Characterized in that the process.

In the circulation path secondary processing step and the circulation path tertiary processing step, the spiral and the screw bone is characterized in that the same pitch (Pitch).

Both ends of the helix is characterized in that it meets the switching guide groove.

In the circulation path tertiary processing step, a part of the tab is inserted into the semi-finished product, and the tab carriage is characterized in that the chuck moves linearly in the direction of the chuck in a non-powered state when the chuck is rotated.

The finished product recovery step is characterized in that the process of penetrating the tap into the finished product by rotating the finished product in the same direction as the processing direction of the third circulation processing step.

The setting step is characterized in that the process of fixing the mounting device and the semi-finished product to the chuck at the same time after inserting the semi-finished product in the installation having a larger diameter than the outer diameter of the semi-finished product.

One side of the installation port, characterized in that the elastic slit is provided to selectively generate the elastic restoring force by the force applied by the chuck.

According to the processing method of the present invention having such a configuration, there is an advantage that the defective rate is reduced and the productivity is improved.

Hereinafter, a configuration of a nut manufactured by an internal processing method of a ball screw nut according to the present invention will be described with reference to FIGS. 1 to 3.

1 is a perspective view showing the front appearance of the ball screw nut processed according to an embodiment of the present invention, Figure 2 is a perspective view showing a rear appearance of the ball screw nut manufactured according to an embodiment of the present invention 3 is a cross-sectional view of the section II ′ of FIG. 1 showing an internal configuration of a nut for a ball screw manufactured according to an embodiment of the present invention.

As shown in these figures, the nut 100 manufactured according to the present invention has a cylindrical shape with a perforated inside and a screw (not shown with screw) having an outer diameter corresponding to the inner diameter is inserted into the perforated inside.

In addition, a spiral groove for circulating the ball is formed in a spiral shape on the outer surface of the screw, and a circulation path 110 for circulating the inner circumferential surface and the inside is formed in the nut 100.

That is, the circulation path 110 is a screw bone 112 recessed in a spiral shape so as to have a semicircular cross section in a shape and a position corresponding to the spiral groove on the inner circumferential surface of the nut 100, and the perforated nut 100 It comprises a plurality of straight guide holes 114 drilled in the left / right direction with respect to the center portion.

The screw valley 112 and the straight guide hole 114 are formed in a number corresponding to each other. That is, when the screw bone 112 is formed in four rows that do not meet each other, the four straight guide holes 114 are formed to be perforated to connect with the screw bone 112 corresponding to each row.

Accordingly, the ball is infinitely circulated by moving the inner circumferential surface of the nut 100 along the spiral groove of the screw and the screw bone 112 in a spiral shape and then moving in the opposite direction of the nut 100 along the straight guide hole 114. Done.

A switching guide groove 116 is provided between the screw valley 112 and the straight guide hole 114. The switching guide groove 116 guides the ball in a spiral motion along the screw bone 112 or guides the ball linearly along the straight guide hole 114 to the screw bone 112 or the straight guide hole 114. It is formed at both ends of the linear guide hole 114 in a configuration for switching.

Accordingly, both ends of the screw bone 112 is connected to the switching guide groove 116, the converted inner groove is connected to the straight guide hole 114, the screw bone 112 and the straight guide hole 114 is the ball To guide the circulation.

Hereinafter, the configuration of the lathe apparatus 200 used in the internal processing method of the ball screw nut 100 will be described with reference to FIGS. 4 and 5.

4 is a perspective view showing the configuration of a processing apparatus used in the internal processing method of the ball screw nut according to the present invention, Figure 5 is a processing apparatus used in the internal processing method of the ball screw nut according to the present invention. A perspective view showing in detail the main configuration of the is shown.

As shown in these drawings, the lathe 200 is a device for rotating the bar (棒材) to the outside or internal processing, the lathe 200 used in the present invention is a general lathe 200 Some modifications were made to make it easier to process the threaded bone 112 of the nut 100.

The lathe 200 is provided with a chuck 210 which rotates in a state where the workpiece is fixed, and an installation tool 220 is provided at an inner center of the chuck 210.

The mounting hole 220 is selectively separated from the chuck 210 is inserted into the semi-finished product (the nut semi-finished product before the threaded bone 112 is formed), the inside of the installation 220 is slightly larger than the outer diameter of the semi-finished product A hole is formed to have an inner diameter, and the outer circumferential surface of the mounting hole 220 is provided with an elastic slit 222 that is slit long in the inward direction.

Therefore, when the mounting fixture 220 is bitten and fixed to the chuck 210 in the state in which the semi-finished product is inserted into the mounting fixture 220, the pressure transmitted from the chuck 210 to the mounting fixture 220 is installed. By reducing the inner diameter of the 220 to be delivered to the semi-finished product can be fixed to the chuck 210 by the installation port 220.

At this time, the installation tool 220 is maintained in the state in which the elastic restoring force is generated by the elastic slit 222, when the pressure applied from the chuck 210 is removed, the installation tool 220 is restored to the original state It is separable from the semifinished product.

A tab feeder 240 is provided on the right side of the shelf apparatus 200. The tab feeder 240 is a configuration in which the tab 242 for forming the screw bone 112 in the nut 100 is installed, and does not include a separate power unit in the longitudinal direction of the shelf apparatus 200 ( 3, it is configured to linearly reciprocate in the left / right direction).

To this end, a tab mounting portion 244 for fixing the tab 242 is provided at an upper portion of the tab carriage 240, and a rail 246 for guiding linear reciprocating motion of the tab carriage 240 is provided at a lower portion thereof. Is preferably provided.

In addition, the center of the tab 242 whose movement is limited by the tab installation unit 244 corresponds to the center of the chuck 210.

Accordingly, when the tab feeder 240 is moved to the left to insert the tab 242 to a predetermined depth into the semi-finished product and then rotate the chuck 210, the tab 242 is screwed on the inner circumferential surface of the nut 100. While processing 112, the left side is dragged. At this time, the tab feeder 240 is also smoothly moved to the left along the rail 246.

Therefore, the tab feeder 240 and the rail 246 are preferably configured to minimize the friction force. Because, when the frictional force between the tab feeder 240 and the rail 246 increases, the screw bone 112 processed by the tab 242 does not have a semi-circle shape but has an ellipse shape, and thus, the nut 100 This is because it causes a defect.

Hereinafter, a method of processing the inside of the ball screw nut 100 using the lathe apparatus 200 configured as described above will be described with reference to FIGS. 6 to 9.

6 is a flow chart showing the internal processing method of the ball screw nut according to the present invention, Figure 7 is a cross-sectional view showing the internal configuration of the semi-finished product in the internal processing method of the ball screw nut according to the present invention. .

8 is a cross-sectional view showing the internal configuration of the semi-finished product of the circulation path primary processing step is completed in the internal processing method of the ball screw nut according to the present invention, Figure 9 is an internal processing of the ball screw nut according to the present invention In the method, a cross-sectional view showing the internal configuration of the semifinished product in which the circulation path secondary processing step is completed is shown.

6, the internal processing method of the nut includes a semi-finished product preparation step (S100) for preparing a semi-finished semi-finished product with a perforated interior, and a circular path primary process for processing a part of the circulation path 110 of a ball. Machining step (S200), semicircular product of the circulation path secondary processing step (S300) to form a spiral on the inner peripheral surface of the semi-finished product of the circulation path 110, and the spiral (see reference numeral 111 in FIG. Setting step (S400) for fixing to the chuck (210.Chuck) of the 200 and the tab 242 installed in the tab carriage 240 to reciprocate linearly and then match the spiral and then rotate the chuck 210 in a semi-circular shape Circular path tertiary processing step (S500) to form a threaded bone 112 having a cross-section and the separation step of separating the finished product undergoing the circular path tertiary processing step from the chuck (210.Chuck) with the tab 242 (S600), and finished product recovery step (S700) for separating the finished product from the tab 242 The.

In the semi-finished product preparation step (S100), the semi-finished product has a cylindrical shape perforated inside, and is produced as a casting.

In addition, the path guide groove 116 and the straight guide hole 114 are formed in the path primary processing step (S200). That is, the straight guide hole 114 is radially drilled by the number corresponding to the number of the screw bones 112 to be processed later (see FIG. 7), and the length center of the semi-finished product at both ends of the straight guide hole 114. The switching guide groove 116 recessed in the direction is formed recessed (see FIG. 8).

In addition, since the inner circumferential surface of the semi-finished product is formed of a casting and has a rough surface in the first circulation path processing step (S200), drilling may be performed to have an inner diameter dimension corresponding to the outer diameter of the screw.

When the circulation path primary processing step (S200) is completed, the secondary circulation path processing step (S300) for forming a spiral on the inner peripheral surface of the semi-finished product is carried out. The circulation path secondary processing step (S300) is formed to guide the position of the screw bone 112 to be processed later, to guide the correct insertion position of the tab 242 inserted therein.

More specifically, in the path primary processing step (S200), the spiral is recessed shallower than the depth of the screw bone 112 and is formed to correspond to the pitch (Pitch) of the screw bone 112.

Therefore, when the circulation path secondary processing step (S300) is completed, the semi-finished product has an internal shape as shown in FIG.

Thereafter, the setting step S400 is performed. The setting step (S400) is fixed to the chuck 210, the mounting fixture 220 is inserted into the semi-finished product, the tab 242 is fixed to the tab feeder 240 to the center of the tab 242 and semi-finished products It is a step to set the center of the lie in a straight line.

At this time, when the chuck 210 is applied to the center direction, such pressure is transmitted to the mounting hole 220 to generate an elastic restoring force, the mounting hole 220 by pressing the outer peripheral surface of the semi-finished product while the inner diameter is smaller The semifinished product may be fixed to the chuck 210.

When the setting step (S400) is completed, the third round processing step (S500) is performed. The circulation path tertiary processing step (S500) is a process of forming the screw bone 112 in the same position as the spiral.

In more detail, the left end of the tab 242 is in contact with the switching guide groove 116 and the chuck 210 in a state in which a force in the left direction is applied to the tab feeder 240. When rotated, the tab 242 is rotated along a spiral extending with the conversion guide groove 116 to form a screw bone 112 deeper than the spiral.

In this case, since the tab feeder 240 is coupled to integrate with the tab 242, the tab 242 linearly moves to the left along the rail 246 during the process of forming the screw valley 112.

When the tab 242 is conveyed by a predetermined length in the left direction and the formation of the threaded bone 112 is completed, the nut 100 is substantially in a state of being completed.

Thereafter, a separation step (S600) is performed to separate the screw bones 112 from occurring by the tab 242.

That is, since the screw bone 112 processed in the circulation path tertiary processing step (S500) may cause a defect such as being taken when the tab 242 is rotated in the opposite direction to form, the finished product recovery step (S700). In order to perform the separation step (S600) is carried out before.

In the separating step (S600), the nut 100 and the mounting hole 220 are separated from the chuck 210, and the tab 242 is separated from the tab carrier 240 in a state inserted into the nut 100. do.

At this time, when the force applied to the mounting tool 220 is removed, the elastic slit 222 of the mounting tool 220 is opened so that the nut 100 can be easily separated from the mounting tool 220.

Thereafter, the tab 242 penetrates the inside of the finished product of the nut 100 in the same direction as the machining direction of the circulation path tertiary processing step (S500), and through this process, the nut 100 is separated from the tab 242. It becomes possible.

The scope of the present invention is not limited to the above-exemplified embodiments, and many modifications based on the present invention will be possible to those skilled in the art within the above technical scope.

As described in detail above, in the internal processing method of the ball screw nut according to the present invention, a separately manufactured mounting fixture is installed on the chuck and the threaded bone is processed using the tab while fixing the semi-finished product to the mounting fixture.

Therefore, since the screw bone can be formed in the correct position there is an advantage that the failure rate is reduced.

In addition, the present invention is further provided with a separate tab feeder for the tab processing of the semi-finished product on one side of the shelf, it is configured to minimize the tensile force applied to the semi-finished product so that the tab feeder is transported with no force during the processing of the screw bone.

Therefore, there is an advantage that the accuracy of the screw bone is improved, and the productivity is increased.

Claims (8)

A semi-preparation step for preparing a semi-finished product with a cylindrical shape perforated therein; A first step of the circulation path for processing a part of the circulation path of the ball, A secondary circulation step of forming a spiral on an inner circumferential surface of the semi-finished product among the circulation paths; A setting step of fixing the spiral-finished semifinished product to the chuck of the lathe; A third step of the circular path for forming a screw bone having a semi-circular cross section by rotating the chuck after matching the tabs and the spirals installed on the linear tab reciprocating carriage; A separation step of separating the finished product, which has undergone the circulation path tertiary processing step, from the chuck with a tab, The internal processing method of the ball screw nut, characterized in that consisting of a finished product recovery step of separating the finished product from the tab. The method of claim 1, wherein the circulation path primary processing step, Switching guide groove for converting the spiral motion of the ball into a linear motion, The inner processing method of the ball screw nut, characterized in that the process of processing a straight guide hole for guiding the ball in the linear direction is changed along the conversion guide groove. The method of claim 2, wherein in the circulation path secondary processing step and the circulation path tertiary processing step, The spiral thread and the screw bone has the same pitch (Pitch), the internal processing method of the ball screw nut. 4. The internal processing method of a ball screw nut according to claim 3, wherein both ends of the spiral meet a switching guide groove. According to claim 1, In the circulation path tertiary processing step, A part of the tab is inserted into the semi-finished product, and the tab feeder moves in a straight line in the direction of the chuck in a non-powered state when the chuck is rotated. According to claim 2, The finished product recovery step, An inner processing method of a ball screw nut, characterized in that the process of penetrating the tab into the finished product by rotating the finished product in the same direction as the processing direction of the circulation path tertiary processing step. The method of claim 1, wherein the setting step, An internal processing method of a ball screw nut, characterized in that the process of fixing the mounting fixture and the semi-finished product to the chuck at the same time after inserting the semi-finished product in the installation having a larger inner diameter than the semi-finished product. According to claim 7, On one side of the mounting hole, Internal processing method of the ball screw nut, characterized in that the elastic slit is provided to selectively generate an elastic restoring force by the force applied by the chuck.

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