Gear processing device

Abstract

To provide a gear processing device which reliably discharges chips occurring during cutting or grinding to prevent the chips from being caught and improve the tool life, processing accuracy, and processing efficiency.SOLUTION: A gear processing device 100 according to the invention includes: a workpiece spindle 110 to which a chuck 114 for holding a workpiece 102 is attached and which rotates the workpiece; a reference metal 112 which is attached to the chuck and with which the workpiece contacts when held by the chuck; a supply passage 116 which is provided within the workpiece spindle to supply a coolant, air, or mist to the reference metal; and a passage 131 provided at the reference metal, the passage having discharge ports 130 arranged along a tooth shape formed at the workpiece and configured to discharge the coolant, air, or mist supplied from the supply passage to the workpiece.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a gear machining device that machines a gear by cutting or grinding a workpiece. [Background technology]

[0002] Known gear machining methods involve moving a tool relative to the workpiece (e.g., skiving, shaping, and hobbing). In these machining methods, coolant is ejected toward the workpiece or tool during machining to cool them and remove chips generated during machining.

[0003] For example, Patent Document 1 describes a throw-away tip and a milling cutter. The cutter body of the milling cutter has a cutting fluid supply hole and a tip mounting seat. The throw-away tip is a plate-shaped tip that is detachably mounted on the tip mounting seat of the cutter body and is further provided with a cutting fluid supply groove.

[0004] The cutting fluid supply hole in the cutter body penetrates the cutter body to supply cutting fluid (coolant) to the throw-away tip. The cutting fluid supply hole also opens to the tip mounting seat and communicates with the cutting fluid supply groove in the throw-away tip that is in close contact with the tip mounting seat. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-39387 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, holes are provided in the cutter body of the milling cutter and grooves are provided in the throw-away tip, so that coolant is discharged toward the cutting edge of the throw-away tip. In other words, in Patent Document 1, coolant is discharged from the tool side to cool the workpiece and cutting tool and to discharge chips.

[0007] However, when coolant is discharged from the tool side, chips can accumulate in the space between the workpiece's inner surface and the reference metal attached to the chuck that holds the workpiece, especially when machining the inner surface of an internal gear. This can cause chips to get caught during cutting, reducing tool life and machining accuracy. Furthermore, reducing chip catches requires lowering cutting conditions, which results in poor machining efficiency.

[0008] In view of the above problems, the present invention aims to provide a gear cutting device that can reliably discharge chips generated during cutting or grinding, thereby preventing the chips from getting caught and improving tool life, cutting accuracy, and cutting efficiency. [Means for solving the problem]

[0009] In order to solve the above problems, a typical configuration of a gear machining device according to the present invention is characterized by comprising: a work spindle to which a chuck for holding a work is attached and which rotates the work; a reference metal attached to the chuck and against which the work abuts when held by the chuck; a supply passage provided inside the work spindle for supplying coolant, air or mist to the reference metal; and a flow passage provided in the reference metal, which is arranged along the tooth profile formed on the work and includes an outlet for discharging the coolant, air or mist supplied from the supply passage toward the work.

[0010] The flow passages are preferably holes or grooves arranged at positions corresponding to the tooth tip, tooth flank, and tooth bottom of the workpiece. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a gear cutting device that can reliably discharge chips generated during cutting or grinding, thereby preventing the chips from getting caught and improving tool life, cutting accuracy, and cutting efficiency. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram illustrating a main part of a gear machining device according to an embodiment of the present invention, together with a workpiece. [Figure 2] FIG. 2 is a diagram showing the workpiece and the reference metal of FIG. 1. [Figure 3] FIG. 10 is a diagram showing a modified example of the ejection port. [Figure 4] 10A and 10B are diagrams showing another embodiment of the reference gold and the discharge port. DETAILED DESCRIPTION OF THE INVENTION

[0013] 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 the embodiments are merely examples for facilitating understanding of the invention and, unless otherwise specified, do not limit the present invention. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present invention are not shown.

[0014] 1 is a diagram illustrating the main components of a gear machining apparatus 100 according to an embodiment of the present invention, together with a workpiece 102. The gear machining apparatus 100 moves a cutting tool 104, such as a skiving cutter, relative to the workpiece 102, which is an object to be machined, to cut the inner peripheral surface of the workpiece 102 and generate internal teeth 108 (see FIG. 2(a)).

[0015] 1, the gear cutting machine 100 includes a workpiece spindle 110 and a reference die 112. A chuck 114 for holding the workpiece 102 is attached to the workpiece spindle 110, and the workpiece 102 held by the chuck 114 is rotated. The chuck 114 is, for example, a collet chuck that includes a slot or a tapered portion, and securely holds the workpiece 102.

[0016] The reference metal 112 is attached to a chuck 114 and is a member against which the workpiece 102 abuts when the workpiece 102 is held by the chuck 114, thereby positioning the workpiece 102. Note that the figure shows the state of the workpiece 102 before it is held by the chuck 114.

[0017] A supply path 116 is provided inside the workpiece spindle 110 to supply coolant, air, or mist to the reference metal 112. Tips 116a and 116b of the supply path 116 reach a back surface 112b of the reference metal 112 opposite to a front surface 112a that faces the workpiece 102, as shown in the figure.

[0018] The supply passage 116 is also connected to a workpiece spindle internal flow path 120 which is connected to a rotary joint 118, and coolant, air or mist is supplied via this workpiece spindle internal flow path 120. A coolant, air or mist supply source 121 is connected to the rotary joint 118. In other words, the gear cutting machine 100 is capable of not only wet cutting using coolant when cutting the workpiece 102, but also dry cutting using air and semi-dry cutting using mist.

[0019] Furthermore, the chuck 114 that holds the workpiece 102 is fixed to the workpiece spindle 110 separately from the chuck adapter 122. The chuck adapter 122 is connected to a connecting bolt 126 of a piston 124. The piston 124 is connected to a hydraulic flow path 128 that is connected to the rotary joint 118. A hydraulic tank 129 is also connected to the rotary joint 118. When hydraulic pressure is applied from the hydraulic flow path 128, the connecting bolt 126 operates to retract the chuck adapter 122.

[0020] In this way, the piston 124 retracts the chuck 114 via the chuck adapter 122. Then, the workpiece 102, while held by the chuck 114, comes into contact with the protrusion 112c (see FIG. 2(b)) of the reference metal 112 and is positioned.

[0021] FIG. 2 is a diagram showing the workpiece 102 and the reference die 112 of FIG. 1. Internal teeth 108 are machined on the inner peripheral surface of the workpiece 102 shown in FIG. 2(a) by a cutting tool 104 (see FIG. 1). As a result, a tooth profile including a tooth tip 108a, a tooth flank 108c, and a tooth bottom 108e is formed on the workpiece 102 (see FIGS. 2(a) and 2(c)). Note that the dashed lines shown in FIG. 2(c) are imaginary lines that indicate the contours of the tooth tip 108a, the tooth flank 108c, and the tooth bottom 108e of the internal teeth 108 of the workpiece 102 of FIG. 2(a) that face the reference die 112.

[0022] The reference metal 112 is provided with a plurality of discharge ports 130 as shown in Fig. 2(b). The discharge ports 130 are included in a flow path 131 that penetrates between the front surface 112a and the back surface 112b of the reference metal 112 as shown in the cross-sectional view of Fig. 2(b), and are provided on the front surface 112a of the reference metal 112 as shown in the front view of Fig. 2(b). The discharge ports 130 guide the coolant, air, or mist supplied from the supply path 116 shown in Fig. 1 from the back surface 112b to the front surface 112a of the reference metal 112, and then discharge it toward the workpiece 102 that is in contact with the protrusion 112c of the reference metal 112.

[0023] Fig. 2(c) is an enlarged view of the discharge port 130 provided in the reference metal 112 in Fig. 2(b). In the figure, the tooth profile formed on the workpiece 102 is indicated by a dashed line (phantom line) at a position corresponding to the reference metal 112. The tooth profile formed on the workpiece 102 is a shape including the tooth tip 108a, tooth surface 108c, and tooth bottom 108e of the internal tooth 108 shown in Fig. 2(a), and is formed based on the specifications of the workpiece.

[0024] The discharge ports 130 are arranged along the tooth profile formed on the workpiece 102, as shown in Fig. 2(c). That is, the discharge ports 130 are holes arranged at positions corresponding to the tooth tip 108a, tooth surface 108c, and tooth bottom 108e of the internal tooth 108 shown in Fig. 2(a). The discharge ports 130 are arranged all around the tooth profile formed on the workpiece 102, as shown in Fig. 2(b).

[0025] As a result, the gear processing device 100 can eject coolant, air, or mist from the outlet 130, which is a hole provided in the reference metal 112, toward the tooth tip 108a, tooth surface 108c, and tooth bottom 108e of the internal tooth 108 of the workpiece 102 shown in Figure 2(a).

[0026] Here, when cutting the workpiece 102 to machine the internal teeth 108, if coolant, air, or mist is ejected from the cutting tool 104 side, the machining position is inside the workpiece 102, so chips will accumulate in the space surrounded by the inner surface of the workpiece 102 and the surface 112a of the reference metal 112, and on the chuck 114 side.

[0027] In contrast, the gear machining apparatus 100 discharges coolant, air, or mist toward the workpiece 102 from a discharge port 130 provided on the workpiece spindle 110, i.e., the reference die 112, rather than on the cutting tool 104. This allows the gear machining apparatus 100 to reliably discharge chips generated during cutting from the inner peripheral surface of the workpiece 102 and the reference die 112.

[0028] Therefore, the gear cutting device 100 can prevent chips from getting caught, extend the life of the cutting tool, and improve the cutting accuracy and efficiency.

[0029] In the gear cutting apparatus 100, when gear grinding after hardening, such as hard skiving, is performed, the workpiece 102 already has a tooth profile formed. In such a case, the phase of the workpiece 102 is detected in advance, and the workpiece 102 is held by the workpiece spindle 110 in a state where the phase is aligned with the discharge port 130 provided in the reference die 112. In this way, even when hard skiving is performed in the gear cutting apparatus 100, it is possible to prevent chips from getting caught, extend the life of the cutting tool, and further improve the machining accuracy and efficiency.

[0030] Furthermore, in the gear machining device 100, the outlets are not limited to the outlet 130 in Figure 2(c) as long as they are arranged along the tooth profile formed on the workpiece 102 and eject coolant, air, or mist toward the workpiece 102.

[0031] As an example, the reference metals 112A and 112B shown in FIGS. 2(d) and 2(e) are provided with discharge ports 130A and 130B, respectively. The dashed lines shown in FIGS. 2(d) and 2(e) are imaginary lines showing the contours of the tooth tips 108a, tooth flanks 108c, and tooth bottoms 108e of the internal teeth 108 of a workpiece 102 having a small module, for example, that faces the reference metals 112A and 112B. The discharge port 130A is arranged so as to overlap the tooth tips 108a and tooth flanks 108c of the internal teeth 108, as shown in FIG. 2(d). The discharge port 130B is arranged so as to overlap the tooth tips 108a and tooth flanks 108c of the internal teeth 108, or so as to overlap the tooth flanks 108c and tooth bottoms 108e, as shown in FIG. 2(e).

[0032] Therefore, in the gear cutting device 100, by discharging coolant, air, or mist toward the workpiece 102 from the discharge ports 130A, 130B provided on the base plates 112A, 112B, chips can be discharged even when machining a workpiece 102 with a small module, depending on the workpiece specifications. This prevents chips from getting caught, extends the tool life, and improves machining accuracy and efficiency. Furthermore, for a workpiece 102 with a small module, the teeth of the internal teeth 108 are small, so chips can be discharged by discharging coolant, air, or mist from the discharge ports 130A, 130B, which have fewer teeth than the discharge port 130 shown in Figure 2(c).

[0033] Figure 3 shows modified examples of the discharge ports 130. The discharge ports 130 shown in Figure 2(c) are arranged along the tooth profile of the internal teeth 108, but the reference plate 112C shown in Figure 3(a) is provided with discharge ports 130C at double the density, with the tooth profile shifted by 1 / 2 pitch. Also, the reference plate 112D shown in Figure 3(b) is provided with discharge ports 130D at four times the density, with the tooth profile shifted by 1 / 4 pitch.

[0034] In this way, the reference metals 112C and 112D are provided with a larger number of outlets 130C and 130D than the above-described outlet 130, so there is no need to align (align) the outlets 130C and 130D with the positions of the tooth tip 108a, tooth surface 108c, and tooth bottom 108e of the internal tooth 108 based on the workpiece specifications of the workpiece 102 shown in Figure 2(a). This simplifies the machining procedure for the workpiece 102. If the flow rate of the coolant, air, or mist is sufficient, the area covering the tooth tip 108a to the tooth bottom 108e may be made into a mesh-like porous outlet surface.

[0035] 4A and 4B are diagrams showing another embodiment of the reference metal 112 and the discharge port 130. The reference metal 112E is provided with a discharge port 132 as shown in Fig. 4A. Unlike the discharge port 130 shown in Fig. 2B and Fig. 2C, which is a hole, the discharge port 132 is a groove (slit) that penetrates the reference metal 112E.

[0036] As shown in Fig. 4(b), the discharge ports 132 are arranged along the tooth profile formed on the workpiece 102. The dashed lines shown in Fig. 4(b) are imaginary lines that indicate the contours of the tooth tips 108a, tooth flanks 108c, and tooth bottoms 108e of the internal teeth 108 of the workpiece 102 in Fig. 2(a) that face the reference metal 112E. In other words, the discharge ports 132 are arranged around the entire circumference at positions that correspond to the tooth tips 108a, tooth flanks 108c, and tooth bottoms 108e of the internal teeth 108.

[0037] This allows the gear processing device 100 to eject coolant, air, or mist from the outlet 132, which is a groove provided in the reference plate 112E, toward the tooth tip 108a, tooth surface 108c, and tooth bottom 108e of the internal tooth 108 of the workpiece 102.

[0038] 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 those skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that such modifications and alterations also fall within the technical scope of the present invention. [Industrial Applicability]

[0039] The present invention can be used as a gear machining device that cuts or grinds a workpiece to machine a gear. [Explanation of symbols]

[0040] 100... gear machining device, 102... workpiece, 104... cutting tool, 108... internal tooth, 108a... tooth tip, 108c... tooth surface, 108e... tooth bottom, 110... work spindle, 112, 112A, 112B, 112C, 112D, 112E... reference metal, 112a... surface of reference metal, 112b... back surface of reference metal, 112c... protrusion of reference metal, 114... chuck, 11 6...supply passage, 116a, 116b...tip of supply passage, 118...rotary joint, 120...passage in work spindle, 121...supply source, 122...chuck adapter, 124...piston, 126...connecting bolt, 128...hydraulic passage, 129...hydraulic tank, 130, 130A, 130B, 130C, 130D, 132...discharge port, 131...passage

Claims

1. a work spindle having a chuck attached thereto for holding a workpiece and rotating the workpiece; a reference metal attached to the chuck, against which the workpiece abuts when the workpiece is held by the chuck; a supply path provided inside the work spindle for supplying coolant, air, or mist to the reference metal; a flow path provided in the reference metal, the flow path being arranged along the tooth profile formed on the workpiece, and including an outlet for discharging the coolant, air or mist supplied from the supply path toward the workpiece.

2. 2. The gear machining device according to claim 1, wherein the discharge port is a hole or a groove disposed at a position corresponding to a tooth tip, a tooth surface, or a tooth bottom of the workpiece.

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