JPS6237601Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a taper machining attachment that is used as an addition to the tool rest of a lathe, and is intended to easily realize taper cutting and taper thread cutting.

By the way, when performing taper machining using a lathe, the tip of the tailstock spindle of the tailstock is slightly shifted toward or away from you in a horizontal plane, so that the center line of rotation of the workpiece is aligned with the main axis of the headstock. It is customary to make the feeding direction of the feeder obliquely intersect with the center line of the workpiece, or by slightly rotating the upper feeder on the carriage in a horizontal plane so that the feeding direction of this feeder is obliquely intersecting the center line of rotation of the workpiece. .

However, the former method of shifting the tip of the tailstock shaft cannot be adopted when the workpiece is supported by a chuck without relying on the tailstock, and the latter method of rotating the upper feedstock cannot be adopted. In this case, the automatic feed of the carriage cannot be used to move the cutting tool, and the operator must rely on the manual feed of the upper feed, making it impossible to perform taper machining efficiently.

Furthermore, in each of the above-mentioned methods, the amount of displacement of the tip of the tailstock spindle or the amount of rotation of the upper feed table is carefully fine-tuned prior to taper machining, and after the taper machining is completed, this is carefully fine-tuned again to return to the original state. Since it needs to be repaired, these ancillary works require a great deal of effort. Therefore, even when tapering the bottom surface of a screw or cutting a taper thread according to a taper that is often used and is particularly standardized, for example, a taper of 1/16 as specified by the JIS standard for taper threads for pipes. , the work efficiency is poor, making it impossible to reduce production costs.

This invention deals with the above-mentioned situation when performing taper machining on a lathe, and in order to easily realize taper machining based on this, which is often used, the present invention has been developed by The cutting tool can be automatically moved in a direction perpendicular to the feed direction, and the feeding direction of the cutting tool can be moved along the axis of the main shaft that supports and rotates the workpiece. By setting in either the direction or the direction perpendicular to this, taper processing can be performed on either the circumferential surface or the end surface of the workpiece.
Hereinafter, an embodiment shown in the drawings will be described in detail.

1 to 3 show the case where the outer peripheral surface of a workpiece is tapered using the attachment according to the present invention. In the figures, 1 is the base of the attachment, which has an L-shaped planar shape. The base 1 is removably attached to the tool stand at the top of the carriage of the lathe using the fins 2, in the same way as a normal cutting tool.
Therefore, the entire base 1 or the attachment is sent in the direction of the axis O...O of the main shaft by the carriage. This base 1 has a first housing 3 disposed parallel to the spindle axis O...O at a predetermined interval.
and a second casing 4 extending from the casing 3 in a direction orthogonal to the main axis are respectively fixed, and these casings 3 and 4 butt against each other in an inverted T shape when viewed from above. Under such conditions, they are effectively integrated. However, inside the first housing 3,
A detection shaft 5, which is long in the direction of the main shaft axis O...O, is inserted so that it can only reciprocate in the axial direction without rotating, and is fed by a spring 6 housed in one end inside the housing. It is elastically biased so as to protrude toward the front side (left side in the drawing). A rack 7 is formed along the length of the detection shaft 5, and this rack is located on the upper surface of the shaft 5 described above in the illustrated example. On the other hand, a rotating shaft 8 that is long in the direction perpendicular to the feeding direction is inserted into the half of the second housing 4 on the first housing 3 side. This rotating shaft 8 has a pinion 9 at the end on the first housing 3 side and a large diameter section 10 at the middle.
have a threaded shaft 11 at the end on the opposite side of the pinion. The rotating shaft 8 includes a bearing 12 housed in the second housing 4 so as to surround the large diameter portion 10 thereof, and a set screw 13 screwed into the end of the second housing 4 on the first housing side. The pinion 9 is supported so that it can only rotate freely, and is projected into the first housing 3 through the push screw 13, and the pinion 9 provided at the projecting end is connected to the detection shaft 5 in the illustrated example. It is positioned above the rack 7 and is always engaged with the rack 7. In addition, in the main shaft side half of the second housing 4,
A response shaft 14 is inserted coaxially with the rotating shaft 8 so that it can only reciprocate in the axial direction without rotating, and is inserted through a screw hole 15 provided at the end on the rotating shaft 8 side. It is threadedly engaged with the threaded shaft 11 of the shaft 8. The female and male screws in the screw hole 15 and the screw shaft 11 are left-handed screws in the illustrated example.
A cutting tool holder 16 is fixed to the end of the response shaft 14 on the main shaft side that always protrudes from the second casing 4. This holder 16 is designed to allow an arbitrarily selected cutting tool 18 to be removably attached to the holder 16 using one or several (two in the illustrated example) bolts 17 in the same way as a normal tool stand. Note that for the detection axis 5 described above, the stopper 19
is available. This stopper 19 is mounted on the left side of the detection shaft 5 in the drawing, that is, on the front side of the cutting tool 18 or the attachment in the feeding direction, to a part that is not movable with respect to the feeding direction, such as a headstock, so that its position can be adjusted. shall be.
It is also assumed that at least a portion of the workpiece 20 that requires processing is supported on the main axis O-O of the lathe and rotated on this axis O-O. It does not matter whether the workpiece 20 is supported by a tailstock or a chuck.

The entire attachment configured as described above is attached to the tool stand at the top of the carriage of the lathe using the fins 2 of the base 1, and the tool holder 16 is attached to the tool holder 16, which is attached to the fins 2 of the base 1. A cutting tool selected accordingly, for example, a cutting tool 18 suitable for tapering the outer circumferential surface, is attached.

Therefore, first, align the cross feed table on the carriage with the spindle axis O.
-0, while moving the carriage itself in the direction of the spindle axis O-O to bring the cutting edge of the cutting tool 18 to the machining start point of the workpiece 20 as shown in Fig. 1. . At this time, so that the tip of the detection shaft 5 comes into contact with the stopper 19,
The mounting position of the stopper is predetermined.

Next, while rotating the workpiece 20, the carriage is moved parallel to the spindle axis OO to the left in the drawing. For this movement, the automatic feed function provided on the lathe can be used as is. Then, the cutting edge of the cutting tool 18 is also sent in the same direction, and machining of the workpiece 20 is started. On the other hand, the detection shaft 5, which had already been in contact with the stopper 19, is prevented from moving by the stopper 19 at the same time as the processing starts, and is relatively moved backward in the feeding direction into the first housing 3. It is pushed in even deeper against the internal spring 6. The relative movement of the detection shaft 5 is achieved by rotating the rotation shaft 8 via the pinion 9 meshed with the rack 7 of the detection shaft 5, and by rotating the rotation shaft 8 in the axial direction of the response shaft 14 via the screw shaft 11 and screw hole 15 screwed together. gives the behavior of Therefore, in the illustrated example, the pinion 9 is located above the detection shaft 5 and rotates counterclockwise in the drawing of FIG. is about to enter the latter, the above-described axial movement of the response shaft 14 causes the cutting tool 18 to move in the direction of retreating from the workpiece 20, that is, in the direction away from the main shaft.

Incidentally, the amount of axial movement of the detection shaft 5 and the amount of axial movement of the response shaft 14 are proportional to each other, and therefore, in the illustrated example, the amount of leftward movement of the cutting tool 18 and the amount of movement from the workpiece 20 are proportional to each other. The amount of retraction of the cutting edge is proportional. This relationship is illustrated in a slightly exaggerated manner as shown in FIG. 4. That is, after the tip of the detection shaft 5 is brought into contact with the stopper 19, the carriage moves a distance F in the direction of arrow A parallel to the rotation center line (spindle axis) O-O of the workpiece.
, the detection shaft 5 is relatively moved by the same distance in the opposite direction, so the response shaft 14 and the cutting tool 18 are moved by a distance f in the direction of arrow B at right angles to the center line O-O. do. Therefore, the cutting edge of the cutting tool 18 is actually a distance √ in the direction of arrow C.
It will move by ² + ² , and the inclination of this movement locus with respect to the rotation center line O-O will be f/F. Therefore, the workpiece 20 is tapered or threaded along the chain line 20' in FIG. 1 by the cutting edge of the cutting tool 18 moving as described above, and the taper has the same slope as f/F as described above. Become.

Therefore, the moving distance f of the cutting tool 18 in the direction of arrow B
can be expressed as f=LN...(1), where the rotation speed of the rotating shaft 8 is N, and the lead of the screw of the screw shaft 11 and the screw hole 15 is L, and when the screw is a single screw, The above lead L is equal to the screw pitch. Further, the rotation speed N of the rotating shaft 8 can be expressed as N=F/πD (2) using the travel amount F of the detection shaft 5 and the pitch circle diameter D of the pinion 9, and this equation (2) is , F=πDN …(2)′. Therefore, the taper described above can be expressed as f/F=L/πD (3) based on equations (1) and (2)′ above, and this means that the taper is equal to the pitch of the pinion. This means that it is determined by the circle diameter D and the screw lead L. Therefore, by appropriately selecting a combination of the pitch diameter D and the lead L, it is possible to give the cutting tool 18 operations based on various required tapers.
It becomes easy to taper the lower surface of the thread and cut the taper thread of the pipe taper thread No. 16.

Note that the illustrated example is for tapering the outer peripheral surface of the workpiece 20, but if a hole boring tool or female screw tool is used as the tool 18, taper cutting or taper thread cutting can be performed on the inner peripheral surface of the workpiece. In these cases, the rack 7 is provided on the lower surface of the detection shaft 5 and the pinion 9 is engaged with the rack 7 from the lower surface of the shaft, or the screw shaft 11 and the screw hole 15 are If it is a right-handed thread, the cutting tool 18 is moved forward as the detection shaft 5 is pushed in, so the direction of inclination of the taper can be set in the opposite direction.

Furthermore, the entire attachment is turned in a direction perpendicular to that shown in the figure, the tip of the cutting tool 18 is brought into contact with the center of the end surface of the workpiece, and while the workpiece is rotated, the attachment is placed on the carriage. Adjust the main spindle axis O by using the cross feed function of the cross feed table.
If it is fed in a direction perpendicular to -O, the end face can be tapered.

As described above, the present invention is designed to automatically move the cutting tool forward or backward in a direction orthogonal to the feeding direction in proportion to the amount of movement of the cutting tool in the feeding direction. When using such an attachment, taper processing such as cutting or thread cutting based on the required taper of the workpiece can be automatically and easily performed, and the automatic feed of the carriage or cross feed table can be automatically and easily performed. Since it can be used as is, efficient taper machining can be performed, and since there is no need to displace the tip of the tailstock shaft or rotate the upper feed table, troublesome incidental work can be eliminated, making it possible to perform taper machining efficiently. It is possible to easily realize the simplification of the taper processing using this method, and it is expected to have the effect of reducing production costs by improving work efficiency.

[Brief explanation of the drawing]

Fig. 1 is a plan view with some parts missing showing an embodiment of the present invention, Fig. 2 is a plan view with the entire part omitted, and Fig. 3 is a plan view of the first embodiment of the invention.
FIG. 4, which is a sectional view taken along the - line in the figure, is a diagram illustrating the operating state. 1... Base, 3, 4... Housing, 5... Detection axis, 6... Spring, 7... Rack, 8... Rotation axis,
9... Pinion, 11... Screw shaft, 14... Response shaft, 15... Screw hole, 16... Bit holder,
18... Part-time job, 19... Stopper, 20...
Workpiece, O-O... Spindle axis.

Claims (1)

[Scope of utility model registration request] For a workpiece that is supported on the axis of the main spindle and driven to rotate around the axis, the cutting tool is fed in the axial direction and moved in a direction perpendicular to the feed direction, so that the circumferential surface of the workpiece is An attachment for taper machining of a lathe that performs taper machining on the end face of a workpiece by performing taper machining or by moving a cutting tool in a direction perpendicular to the feeding direction while feeding the cutting tool in a direction perpendicular to the feeding direction, which comprises: a detection shaft that is supported by a housing that holds a cutting tool so as to be able to reciprocate in the feeding direction of the cutting tool and is resiliently biased forward in the feeding direction of the cutting tool; and a shaft that is perpendicular to the feeding direction of the cutting tool that is mounted on the housing A rotary shaft supported so as to be rotatable only on a line and having a pinion that easily meshes with the detection shaft; and a response shaft to which the cutting tool is attached at one end and screwed to the rotating shaft at the other end, and a response shaft fixed in front of the detection shaft in the cutting tool feeding direction. A taper machining attachment for a lathe, comprising a stopper that prevents forward movement and moves the detection shaft rearward relative to the housing in a cutting tool feeding direction.