Angular head

Abstract

To provide an angular head capable of being turnably constituted so as to correspond to the directions of a plurality of machining surfaces.SOLUTION: An angular head includes a shaft portion (5) connected to a main shaft (S) of a machine tool (M) via a shank (4), a head portion (7) on which a sub-main shaft (6) extending in a direction intersecting the main shaft (S) is mounted, and a gear portion (8) that transmits rotation of the main shaft (S) to the sub-main shaft (6).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an angular head, and more particularly to an angular head that can be configured to be rotatable so as to be able to process a plurality of surfaces in different directions. [Background technology]

[0002] In general machine tools such as machining centers, when machining the side surfaces of workpieces in directions other than the main axis direction, an angular head equipped with a sub-spindle at the tip of the main spindle is used. Such angular heads are generally manually swiveled, and once the direction is set and mounted on the machining center, it is difficult to adjust the swivel. Therefore, when automating multi-faceted machining, it is necessary to prepare a number of angular heads, each with a different orientation for each face to be machined. To automate multi-faceted machining, an angular head capable of automatic swivel has been proposed (see, for example, Patent Document 1). In Patent Document 1, a separate swivel table is provided, the head is moved to the table, and the head is rotated by pressing it against the table using vertical movement (Z-axis movement). However, this requires a permanently installed swivel table, which raises the risk of interference with tools, etc. While it is also possible to rotate the head using functions on the machining center, this method requires complex control and requires significant effort and expense. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-036749 Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE INVENTION An object of the present invention is to provide an angular head that can be configured to be rotatable so as to be able to process a plurality of surfaces in different directions. [Means for solving the problem]

[0005] In order to achieve the above object, the angular head of the present invention comprises a shaft portion connected to a main spindle of a machine tool via a shank, a head portion carrying a sub-spindle extending in a direction intersecting the main spindle, and a gear portion transmitting the rotation of the main spindle to the sub-spindle, and is characterized in that it further comprises a switching portion interposed between the shank and the head portion for switching the rotation angle of the head portion based on the rotation direction of the main spindle. [Effects of the Invention]

[0006] The angular head of the present invention includes a shaft portion connected to a machine tool's main spindle via a shank, a head portion carrying a sub-spindle extending in a direction intersecting the main spindle, and a gear portion transmitting rotation of the main spindle to the sub-spindle. The angular head also includes a switching portion interposed between the shank and the head portion for switching the rotation angle of the head portion based on the rotation direction of the main spindle. This structure allows the head portion to be rotated, positioned, and the workpiece to be machined simply by rotating, reversing, and stopping the machine tool's main spindle. The present invention can be applied to conventional machine tools that do not have advanced functions, making it possible to machine multiple surfaces inexpensively and simply.

[0007] In the angular head of the present invention, the switching unit preferably includes a ring portion rotatably held around the shaft portion via a bearing and connected to the head portion, a fixed portion rotatably holding the ring portion from the outside and fixed to the machine tool, a cam groove provided on either the outer circumferential surface of the ring portion or the inner circumferential surface of the fixed portion, and a movable pin engaged with the cam groove while being held displaceable along the axial direction of the spindle on the other of the outer circumferential surface of the ring portion or the inner circumferential surface of the fixed portion. By configuring the switching unit as described above, the pivot angle of the head portion can be freely set based on the shape of the cam groove.

[0008] It is preferable that the cam groove includes a plurality of repeating elements, each of which has a first locking portion that locks the movable pin when the main shaft rotates in one direction, a second locking portion that locks the movable pin when the main shaft rotates in the opposite direction, and a groove portion that guides the movable pin between the first locking portion and the second locking portion.In this way, by including a plurality of repeating elements in the cam groove, each of which has a first locking portion that locks the movable pin when the main shaft rotates in one direction and a second locking portion that locks the movable pin when the main shaft rotates in the opposite direction, the pivot angle of the head unit can be set as desired based on the circumferential length of the repeating elements.

[0009] The cam groove is preferably arranged continuously over the entire circumference of the outer circumferential surface of the ring or the inner circumferential surface of the fixed part, which allows the head part to rotate in all directions around the main axis.

[0010] It is preferable that the head portion rotates based on the rotation direction of the main shaft when the rotational torque applied by the main shaft is equal to or less than the static friction generated between the head portion and the main shaft, while the sub-main shaft rotates based on the rotation of the main shaft when the rotational torque applied by the main shaft exceeds the static friction. By using static friction in this way and not providing a general clutch mechanism, the number of parts is reduced and the structure is simple, thereby improving operational accuracy and reducing maintenance work and the risk of failure. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a cross-sectional view showing an example of an angular head according to an embodiment of the present invention. [Figure 2] 2 is an enlarged perspective view showing a cam groove inside the angular head of FIG. 1. FIG. [Figure 3] FIG. 3 is a development view of the cam groove in FIG. 2. [Figure 4] 10A and 10B are explanatory diagrams showing components that operate when the head unit is turned. [Figure 5]FIG. 3 is an explanatory diagram showing components that operate when the tool rotates. DETAILED DESCRIPTION OF THE INVENTION

[0012] The configuration of the present invention will be described in detail below with reference to the accompanying drawings. Figure 1 shows an angular head according to an embodiment of the present invention, and Figures 2 and 3 specifically show the main parts thereof.

[0013] As shown in Figure 1, the angular head 1 includes a fixed portion 2 that is fixed to the machine tool M, a cylindrical ring portion 3 that is held within the fixed portion 2, a shaft portion 5 that is connected to the main spindle S of the machine tool M via a shank 4, a head portion 7 that mounts a counter-spindle 6 that extends in a direction intersecting the shaft portion 5, a gear portion 8 that transmits the rotation of the main spindle S of the machine tool M to the counter-spindle 6, and a tool holding portion 9 that is provided at the tip of the counter-spindle 6 and holds a tool T.

[0014] The fixed portion 2 is fixed to a positioning block m3 of the machine tool M via a positioning pin 2a. The fixed portion 2 also rotatably holds the ring portion 3 from the outside. The ring portion 3 is rotatably held via a pair of upper and lower bearings 11, 12 arranged around the shaft portion 5, and is connected to the head portion 7. The shank 4 has a tapered shape that allows it to be detachably mounted in a tapered hole m2 of the spindle m1 of the machine tool M.

[0015] The sub-spindle 6 is rotatably held within the head portion 7 via a pair of left and right bearings 13, 14. In this embodiment, the axis Y of the sub-spindle 6 is arranged in a direction perpendicular to the axis X of the main shaft S, but this is not limited to this and the sub-spindle 6 can be configured to be set at any angle.

[0016] The gear section 8 has a bevel gear 8a provided at the tip of the shaft section 5 and a bevel gear 8b provided on the sub-spindle 6 so as to mesh with the bevel gear 8a, and transmits the rotation of the main shaft S of the machine tool M to the sub-spindle 6.

[0017] An annular oil seal 15 is arranged so as to contact the ring portion 3 and the shaft portion 5, and an annular oil seal 16 is arranged so as to contact the head portion 7 and the sub-spindle 6. These oil seals 15, 16 prevent leakage of lubricant (oil) from within the ring portion 3 and the head portion 7, and prevent the intrusion of cutting oil from the outside.

[0018] The angular head 1 described above is equipped with a switching unit 10 that switches the swivel angle θ (see FIG. 3) of the head unit 7 based on the rotation direction of the spindle S of the machine tool M. This switching unit 10 includes a fixed unit 2, a ring unit 3, a cam groove 21, and a movable pin 22. By configuring the switching unit 10 with these components, the swivel angle θ of the head unit 7 can be set arbitrarily based on the shape of the cam groove 21.

[0019] Cam grooves 21 are provided on the outer peripheral surface of ring portion 3. A plurality of movable pins 22 that engage with cam grooves 21 are provided on the inner peripheral surface of fixed portion 2. Rails 2b that guide these movable pins 22 are provided on the inner peripheral surface of fixed portion 2 so as to extend along axis X of main shaft S. Movable pins 22 are held displaceably on the inner peripheral surface of fixed portion 2 and can move along the axial direction of main shaft S.

[0020] In this embodiment, an example has been shown in which the cam groove 21 is provided on the outer peripheral surface of the ring portion 3 and the movable pin 22 is provided on the inner peripheral surface of the fixed portion 2, but the present invention is not limited to this. Conversely, the cam groove 21 can be provided on the inner peripheral surface of the fixed portion 2 and the movable pin 22 can be provided on the outer peripheral surface of the ring portion 3. In this case, the movable pin 22 is held displaceably on the outer peripheral surface of the ring portion 3 and can move along the axial direction of the main shaft S.

[0021] Furthermore, the cam groove 21 is arranged continuously around the entire outer circumferential surface of the ring portion 3. This allows the head portion 7 to rotate in all directions around the main axis S. Furthermore, the cam groove 21 includes a plurality of repeating elements 23. In this embodiment, the cam groove 21 is made up of 12 repeating elements 23, and each repeating element 23 is formed in a substantially R-shape. The number of repeating elements 23 determines the rotation angle θ of the head portion 7. In this embodiment, since 12 repeating elements 23 are arranged on the outer circumferential surface of the ring portion 3, the head portion 7 is configured to rotate in 30° increments based on a predetermined operation.

[0022] Each repeating element 23 has a first locking portion 24a that locks the movable pin 22 when the spindle S rotates in one direction, a second locking portion 24b that locks the movable pin 22 when the spindle S rotates in the opposite direction, and a groove portion 25 that guides the movable pin 22 between the first locking portion 24a and the second locking portion 24b. The movable pin 22 not only positions the head unit 7 when it rotates, but also serves as a rotation stopper. In this way, the cam groove 21 includes multiple repeating elements 23 that have the first locking portion 24a that locks the movable pin 22 when the spindle S rotates in one direction and the second locking portion 24b that locks the movable pin 22 when the spindle S rotates in the opposite direction. This allows the rotation angle θ of the head unit 7 to be set arbitrarily based on the circumferential length of the repeating elements 23.

[0023] When machining a workpiece using the angular head 1, the shank 4 of the angular head 1 is attached to the spindle m1 of the machine tool M. In this state, by applying a predetermined rotational torque to the shaft portion 5 of the angular head 1 from the main spindle S of the machine tool M, the head portion 7 can be rotated appropriately to machine any surface of the workpiece.

[0024] Specifically, when the main shaft S is rotated in one direction (cutting direction R), static friction causes the ring portion 3 to rotate together with the main shaft S, and the movable pin 22 moves to position P1 within the first locking portion 24a of the cam groove 21, as shown in FIG. 3. This causes the head portion 7 to pivot in one direction. After the pivoting, the rotational torque that exceeds the static friction directly rotates the shaft portion 5. Next, when the main shaft S is rotated in the reverse direction (the opposite direction to the cutting direction R), static friction causes the ring portion 3 to rotate together with the main shaft S, and the movable pin 22 moves from position P1 within the first locking portion 24a of the cam groove 21 to position P2 within the second locking portion 24b. This causes the head portion 7 to pivot in the reverse direction. After the pivoting, the rotational torque that exceeds the static friction directly rotates the shaft portion 5. Thereafter, when the spindle S is rotated again in one direction (cutting direction R), static friction causes the ring portion 3 to rotate together with the spindle S, and the movable pin 22 moves from position P2 to position P1 within the first locking portion 24a of the next repeating element 23. This causes the head portion 7 to pivot in one direction. By performing this operation, the pivot angle θ of the head portion 7 can be changed in 30° increments based on the circumferential length of the repeating element 23.

[0025] Furthermore, in the present invention, instead of a clutch mechanism, static friction caused by components (for example, oil seals 15 and 16, bearings 11, 12, 13 and 14, and bevel gears 8a and 8b) is utilized to arbitrarily switch between the rotation of the head portion 7 and the rotation of the tool T. The structure allows the rotation of the head portion 7 and the rotation of the tool T to be switched depending on the relationship between the rotational torque applied from the main shaft S to the shaft portion 5 and the static friction caused by the components.

[0026] Specifically, when the rotational torque applied from the main spindle S is equal to or less than the static friction generated between the head unit 7 and the main spindle S, the head unit 7 rotates based on the rotation direction of the main spindle S. In this state, the main spindle S and the head unit 7 are connected by static friction. The shaded area in Figure 4 indicates components that move in conjunction with the rotation of the main spindle S when the head unit 7 rotates. On the other hand, when the rotational torque applied from the main spindle S exceeds the static friction generated between the head unit 7 and the main spindle S, the tool T rotates based on the rotation of the main spindle S, allowing the workpiece to be machined. In this state, the rotational torque exceeding the static friction becomes the rotational torque of the sub-spindle 6 in the head unit 7, preventing damage caused by the continuous rotation of the main spindle S and eliminating the need for a clutch mechanism. The shaded area in Figure 5 indicates components that move in conjunction with the rotation of the main spindle S when the tool T rotates. Using static friction in this way and eliminating a conventional clutch mechanism results in a simpler structure with fewer parts, improving operational accuracy and reducing maintenance efforts and the risk of breakdowns.

[0027] The angular head 1 described above includes a shaft section 5 connected to a main spindle S of a machine tool M via a shank 4, a head section 7 mounted with a counter spindle 6 extending in a direction intersecting the main spindle S, and a gear section 8 for transmitting the rotation of the main spindle S to the counter spindle 6, and is provided with a switching section 10 interposed between the shank 4 and the head section 7 for switching the swivel angle θ of the head section 7 based on the rotation direction of the main spindle S. Therefore, the swivel and positioning of the head section 7 and the machining of the workpiece can all be performed simply by rotating, reversing, and stopping the main spindle S of the machine tool M. The present invention can be applied to conventional machine tools M that do not have advanced functions, making it possible to machine multiple surfaces at low cost and in a simple manner. [Explanation of symbols]

[0028] 1 Angular Head 2 Fixed part 3 Ring section 4 shank 5 Shaft 6 Sub-spindle 7 Head 8 Gear section 9 Tool holding part 10 Switching section 11, 12, 13, 14 Bearings 15,16 Oil seal 21 Cam groove 22 Movable pin 23 Repeating Elements 24a, 24b Locking part 25 Groove M machine tool S spindle T-tool X,Y axis

Claims

1. An angular head including a shaft portion connected to a main spindle of a machine tool via a shank, a head portion on which a sub-spindle extending in a direction intersecting the main spindle is mounted, and a gear portion for transmitting rotation of the main spindle to the sub-spindle, An angular head comprising: a switching unit interposed between the shank and the head unit, which switches the rotation angle of the head unit based on the rotation direction of the spindle.

2. 2. The angular head according to claim 1, wherein the switching portion comprises: a ring portion rotatably held around the shaft portion via a bearing and connected to the head portion; a fixed portion rotatably holding the ring portion from the outside and fixed to the machine tool; a cam groove provided on either an outer peripheral surface of the ring portion or an inner peripheral surface of the fixed portion; and a movable pin that engages with the cam groove while being held displaceably along the axial direction of the spindle on the other of the outer peripheral surface of the ring portion or the inner peripheral surface of the fixed portion.

3. 3. The angular head according to claim 2, wherein the cam groove includes a plurality of repeating elements, each of the plurality of repeating elements having a first locking portion that locks the movable pin when the main shaft rotates in one direction, a second locking portion that locks the movable pin when the main shaft rotates in the opposite direction, and a groove portion that guides the movable pin between the first locking portion and the second locking portion.

4. 4. The angular head according to claim 2, wherein the cam groove is disposed continuously over the entire circumference of the outer circumferential surface of the ring portion or the inner circumferential surface of the fixing portion.

5. 4. The angular head according to claim 2 or 3, wherein the head portion turns based on the rotation direction of the main shaft when the rotational torque applied by the main shaft is equal to or less than the static friction generated between the head portion and the main shaft, while the sub-main shaft rotates based on the rotation of the main shaft when the rotational torque applied by the main shaft exceeds the static friction.

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