JP7719362B2 - Skiving machine - Google Patents

Description

The present invention relates to a skiving machine equipped with a tailstock assembly.

Tailstocks are a common feature on lathes, but they are also effective on skiving machines when machining axial workpieces (long workpieces). For example, the machine tool 1 described in Patent Document 1 has a tailstock 15 and tailstock shaft 29 arranged opposite the headstock 13 (see Figure 2). The gear cutting machine 1 described in Patent Document 2 has the tailstock 3' of the workpiece holder 3 arranged on the tailstock arm 12 (see Figure 2).

JP 2013-244582 A Japanese Patent Application Laid-Open No. 2018-176415

The tailstock moves along the centerline of the workpiece to support the tip of the workpiece. In a lathe, the tool is positioned to the side of the workpiece, but in skiving, the workpiece axis and tool axis are positioned opposite each other, with a specified crossed axis angle, and the tool is close to the workpiece axis. As a result, in skiving, the tailstock is prone to interference with the tool and tool spindle, making it difficult to position the tailstock. Even if it were possible to position the tailstock, it was necessary to increase the tool diameter or lengthen the tool holder to avoid interference. This reduced the rigidity of the tool, resulting in problems such as reduced machining accuracy and shortened tool life.

The present invention aims to provide a skiving machine that can easily position the tailstock by avoiding interference with the tool and tool spindle, preventing a deterioration in machining accuracy and shortened tool life.

To solve the above problems, a typical configuration of a skiving machine according to the present invention includes a work spindle, a base, and a tailstock assembly that is detachably attached to the base, extends in the same direction as the work spindle, and positions the tailstock shaft in front of the work spindle, and the tailstock assembly can be attached to multiple positions centered on the work spindle.

The tailstock assembly can be connected to and disconnected from the work spindle, and the multiple positions are preferably positions to which the tailstock assembly can be rotated while connected to the work spindle.

The present invention provides a skiving machine that facilitates tailstock placement by avoiding interference with tools and tool spindles, preventing deterioration of machining accuracy and shortened tool life.

FIG. 2 is a diagram illustrating the periphery of the work axis of the skiving machine according to the present embodiment. 10A and 10B are diagrams illustrating switching of the position of the tailstock assembly. 10A and 10B are diagrams illustrating switching of the position of the tailstock assembly. FIG. 2 is a diagram illustrating the state of a workpiece during machining.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Dimensions, materials, and other specific values shown in these embodiments are merely examples intended to facilitate understanding of the invention and, unless otherwise specified, do not limit the present invention. Furthermore, in this specification and drawings, elements having substantially the same function and configuration are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present invention are not shown.

Figure 1 is a diagram illustrating the work axis and its surroundings of a skiving machine 100 according to this embodiment (see Figure 4 for the tool axis). The skiving machine 100 of this embodiment shown in Figure 1 performs cutting work on a workpiece 102. In this embodiment, the illustration uses an example of generating a gear 104 on the outer periphery of the workpiece 102.

The skiving machine 100 of this embodiment has a work spindle 110 that chucks the workpiece 102. The base 120 is rotatably attached to the work spindle 110.

A tailstock assembly 140 is also attached to the base 120. The tailstock assembly 140 is detachably attached to the base 120 at an attachment portion 142 with a bolt 144. The tailstock assembly 140 has a hydraulic cylinder 146 and an arm 150 arranged in a roughly L-shape. The hydraulic cylinder 146 extends from the base 120 in the same direction as the workpiece spindle 110. The arm 150 extends from the tip of the hydraulic cylinder 146 toward the center of the workpiece spindle 110, and the tailstock shaft 152 is positioned in front of the workpiece spindle 110.

By supplying hydraulic pressure to the hydraulic cylinder 146, the arm 150 moves toward or away from the work spindle 110. The guide 148 guides the extension and retraction movement of the arm 150.

A center 154 that abuts against one end of the workpiece 102 is fitted into the tailstock shaft 152. In the skiving machine 100 of this embodiment, a configuration in which the center 154 is fitted into the tailstock shaft 152 is illustrated. However, this is not limited to this, and another part (not shown), such as a chuck, may be fitted in place of the center 154.

Here, for example, a lathe has a work spindle and tailstock at both ends of the bed. In other words, a lathe has a work spindle and tailstock independently located on either side of the workpiece. The skiving machine described in Patent Document 1 (JP 2013-244582 A) mentioned above also has a headstock and tailstock located at both ends of the bed. Similarly, the skiving machine described in Patent Document 2 (JP 2018-176415 A) has a tailstock arm located on the opposite side of the workpiece spindle, with the workpiece sandwiched between them.

However, in the present invention, the work spindle 110 and base 120 are attached to the skiving machine 100, the tailstock assembly 140 extends via the base 120, and the hydraulic cylinder 146 extends in the same direction as the work spindle 110. The arm 150 then bends around to position the tailstock shaft 152 in front of the work spindle 110. In other words, the tailstock assembly 140 is positioned alongside the work spindle 110, not on the opposite side of the tool shaft across the workpiece. Therefore, there are no tailstock components in the space ahead of the arm 150, ensuring space for the tool shaft 200 (see Figure 4) to move.

Figures 2 and 3 are diagrams illustrating switching the position of the tailstock assembly 140. In this embodiment, the tailstock assembly 140 can be attached to a position on the rear side of the work spindle 110 as shown in Figure 2 (attachment position 122a shown in Figure 3) or a position on the front side of the work spindle 110 as shown in Figure 2 (attachment position 122b shown in Figure 2). Compared to Figure 1, in Figures 2 and 3 the hydraulic cylinder 146 is extended and the arm 150 is separated from the work spindle 110.

Mounting positions 122a and 122b are formed with an oil supply hole 124 that supplies oil to the hydraulic cylinder 146, and a hydraulic hose (not shown) is connected to the tailstock assembly 140. At mounting positions 122a or 122b where the tailstock assembly 140 is not mounted, the oil supply hole 124 is exposed. Therefore, by attaching a cover 130 to mounting position 122a or 122b where the oil supply hole 124 is exposed, chips (not shown) generated when cutting the workpiece 102 can be prevented from entering the oil supply hole 124.

The multiple mounting positions 122a, 122b are positions where the tailstock assembly 140 is rotated while connected to the work spindle 110. The tailstock assembly 140 can be connected to and separated from the work spindle 110 by a connecting member 160.

When switching the tailstock assembly 140 from the position shown in Figure 2 (mounting position 122a) to the position shown in Figure 3 (mounting position 122b), first use the bolt 162 to connect the connecting member 160 to the tailstock assembly 140 and the work spindle 110, as shown in Figure 2. Then, remove the bolt 144 that secures the mounting portion 142 to the base 120. This releases the tailstock assembly 140 from the base 120, and the tailstock assembly 140 is supported by the work spindle 110.

Once the tailstock assembly 140 is supported by the work spindle 110, the work spindle 110 is rotated in the direction of arrow A shown in Figure 2. Once the tailstock assembly 140 is positioned on the front side of the work spindle 110 (mounting position 122b) as shown in Figure 3, the mounting portion 142 is attached to the base 120 with the bolt 144, and the connecting member 160 and bolt 162 are removed from the tailstock assembly 140 and work spindle 110. This separates the tailstock assembly 140 from the work spindle 110 and secures it to the base 120. Then, the cover 130 is attached to the mounting position 122a shown in Figure 3.

Figure 4 is a diagram illustrating the state of the workpiece 102 when it is being machined. Figure 4(a) is a diagram illustrating the state of the workpiece 102 when it is being machined by the skiving machine 100 shown in Figure 2. Figure 4(b) is a diagram illustrating the state of the workpiece 102 when it is being machined by the skiving machine 100 shown in Figure 3. Both Figures 4(a) and (b) show the skiving machine 100 as viewed from above.

As shown in Figure 4(a), when the tool shaft 200 approaches the workpiece 102 from the front side of the workpiece spindle 110, the tailstock assembly 140 is positioned on the rear side of the workpiece spindle 110. This prevents the tool shaft 200 and cutter 210 from interfering with the tailstock assembly 140. On the other hand, as shown in Figure 4(b), when the tool shaft 200 approaches the workpiece 102 from the rear side of the workpiece spindle 110, the tailstock assembly 140 is positioned on the front side of the workpiece spindle 110. Even in this case, it is possible to prevent the tool shaft 200 and cutter 210 from interfering with the tailstock assembly 140.

As described above, with the skiving machine 100 of this embodiment, the tailstock assembly 140 is connected to the workpiece spindle 110 and rotated relative to the workpiece spindle 110. This allows the tailstock assembly 140 to be positioned at multiple positions (mounting positions 122a and 122b).

In this case, the tailstock assembly 140 is placed either at the rear or front side of the workpiece spindle 110, and the tool shaft 200 can be placed in the other space. This makes it possible to avoid interference between the skiving machine 100 and the tool shaft 200 in a minimum amount of space. As a result, it is possible to prevent the tool shaft from becoming larger, and it is possible to prevent a decrease in tool rigidity, which could lead to a deterioration in machining accuracy or a shortened tool life.

While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such examples. It is clear that a person skilled in the art could conceive of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

The present invention can be used as a skiving machine equipped with a tailstock assembly.

100...Skiving machine, 102...Workpiece, 104...Gear, 110...Workpiece spindle, 120...Base, 122a...Mounting position, 122b...Mounting position, 124...Oil supply hole, 130...Cover, 140...Tailstock assembly, 142...Mounting portion, 144...Bolt, 146...Hydraulic cylinder, 148...Guide, 150...Arm, 152...Tailstock shaft, 154...Center, 160...Connecting member, 162...Bolt, 200...Tool shaft, 210...Cutter

Claims (2)

The work spindle and
With the base,
a tailstock assembly that is detachably attached to the base, extends in the same direction as the work spindle, and positions a tailstock shaft in front of the work spindle;
A skiving machine characterized in that the tailstock assembly can be attached to a plurality of positions around the work spindle. the tailstock assembly is connectable to and detachable from the work spindle;
The skiving machine according to claim 1, wherein the plurality of positions are positions to which the tailstock assembly is rotated while connected to the work spindle.