JPH042767Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Use) The present invention relates to a coolant supply device that is included in a machine tool for milling the inner surface of a hole in a workpiece or grooving the inner surface of the hole.

(Prior Art) This type of machine tool is usually provided with a slide mechanism for moving a tool in the radial direction of a spindle. FIG. 4 shows an example of a machine tool having such a slide mechanism, in which a slide guide 4 is provided at the head of a spindle 2 which is rotatably supported by a machine body 1 via a bearing 3. A tool holder 5 is slidably fitted into this slide guide 4. Tool holder 5
has a tool 6 attached to its front part, and integrally has a first rack 7 at its rear part.
A rack 7 is meshed with a pinion 8 disposed within the spindle 3. On the other hand, a rod 9 is provided within the spindle 2 so as to be movable in the axial direction, and a second rack 10 attached to the tip thereof is meshed with the pinion 8. The spindle 2 integrally includes a pulley 11, and rotates when rotation is transmitted to the pulley 11 from a drive source (not shown). Further, the rod 9 has an integral piston 12, and by housing the piston 12 in a cylinder portion 13 provided within the spindle 2, the rod 9 can be moved forward and backward by hydraulic pressure.

With this configuration, when the rod 9 is moved forward as shown by the arrow A, the pinion 8 is rotated counterclockwise by the second rack 10 as shown by the arrow B, and following this, the pinion 8 is rotated counterclockwise as shown by the arrow B. Tool holder 5
moves in the radial direction of the spindle 3 as indicated by arrow C, and as a result, the depth of cut of the tool 6 increases. Note that this slide mechanism may also include a combination of a helical rack instead of the rack and pinion combination described above.

By the way, in the case of machine tools, in order to reduce tool wear and improve machined surface accuracy, coolant is discharged into the tool section. Conventionally, in order to discharge this coolant, a liquid supply pipe was generally arranged around the machine body, and the tip nozzle of this liquid supply pipe faced the vicinity of the tool, so that the coolant was discharged directly to the tool (for example, , Utsukai Showa 58-
Publication No. 51943).

(Problem to be solved by the invention) However, when the part to be machined is deep in a hole, or when the inner surface of the hole and the tool holder 5
(Fig. 4), it is impossible to place the tip nozzle near the tool.
This means that cooling by coolant must be sacrificed to some extent.

As a countermeasure for this, for example, spindle 2 (fourth
It is conceivable to provide a coolant passage inside the case (Figure) and release the coolant from the inside. However, in the case of a machine tool having the above slide mechanism (Fig. 4), since the tool holder 5 is arranged in a direction perpendicular to the spindle 2, it is virtually impossible to provide a coolant passage beyond the tool holder 5. This was impossible, and we were forced to rely on the inefficient discharge pipe mentioned above.

(Means for solving the problems) In order to solve the above-mentioned conventional problems, the present invention
A spindle rod is eccentrically inserted into the outer cylinder spindle so as to be non-rotatable relative to the rod and movable in the axial direction, and inside the front end of the outer cylinder spindle,
A rotary holder for holding a tool is provided in a state in which movement in the axial direction is restricted by the outer cylinder spindle and is screwed onto the spindle rod, and the spindle rod is linearly moved to the rear side of the outer cylinder spindle. The present invention is characterized in that the spindle rod is further provided with a passage for discharging coolant, and this passage is extended to the rear of the outer cylinder spindle.

(Function) In the coolant supply device for a machine tool having the above configuration, when the spindle rod is moved linearly by the drive means, the rotation holder screwed thereon is restricted from moving in the axial direction. Therefore, it rotates around the axis of the spindle rod. At this time, since the center of rotation of the rotary holder is eccentric from the center of rotation of the outer cylinder spindle, the position of the tool attached to the rotary holder moves in the radial direction of the spindle, and the depth of cut can be changed. In addition, the spindle rod rotates together with the outer cylinder spindle and is configured to be movable in the axial direction relative to the outer cylinder spindle, so a coolant discharge path can be easily provided therein, allowing machining. Coolant can be reliably discharged toward the tool regardless of the relationship between the depth and hole diameter and the outer diameter of the outer cylinder spindle.

(Example) Hereinafter, an example of the present invention will be described based on the accompanying drawings.

In FIGS. 1 and 2, reference numeral 22 denotes an outer cylinder spindle, which is rotatably supported by the machine body 20 via a bearing 21. The outer cylindrical spindle 22 consists of a main body part 23 located within the machine body 20 and a head part 24 integrated with the main body part 23 on the front side of the machine body 20. The head section 2
The boss portion 24a fitted into the main body portion 23 of No. 4 is provided with an inner diameter spline eccentric to the axis _O1 of the outer cylinder spindle 22, and a spline cylinder having an outer diameter spline and an inner diameter spline is provided here. 25 is fitted. A spindle rod 26 has a spline portion 26a, and the spline portion 26a is fitted into the spline cylinder 25. That is, the spindle rod 26 is spline-coupled to the outer cylinder spindle 22, so that it can not only rotate together with the outer cylinder spindle 22, but also move in the direction of the axis _O1 of the outer cylinder spindle 22. It is located in

27 is the head portion 24 of the outer cylinder spindle 22;
It is a rotating holder placed inside the holder. Rotating holder 2
7 is rotatably supported by the spindle rod 26 by screwing a threaded body 28 attached to the rear end into a threaded portion 26b provided on the spindle rod 26. The rotary holder 27 also has an annular projection 27a provided on its periphery that engages with the head portion 24 via a thrust bearing 29, thereby restricting movement of the outer cylinder spindle 22 in the axis _O1 direction. has been done. As a result, when the spindle rod 26 is now moved in the direction of the axis _O1 of the outer cylinder spindle 22, the rotating holder 27 will be moved as follows.
Since movement in the axis _O1 direction is restricted,
The spindle rod 26 now rotates around the axis _O2 . Note that when the spindle rod 26 does not move, the rotary holder 27 cannot rotate and is fixed to the outer diameter spindle.

The rotary holder 27 serves to hold a tool, and a tool receiving member 31 having a tool 30 is attached to its front end. Therefore,
Now, when the rotary holder 27 rotates, the tool 30 moves with respect to the rotation center (axial center O ₁ ) of the outer cylinder spindle 22.
The position of will change.

On the other hand, a pulley 33 is fixed to the rear end of the outer cylinder spindle 22 via a first connecting member 32, and a cylinder 35 is fixed to the rear end of the outer cylinder spindle 22 via a first connecting member 32.
is fixed. A piston 36 is housed inside the cylinder 35, and from this piston 36, a first piston rod 37 extends into the main body 23 of the outer cylinder spindle 22, and a second piston rod 38 extends rearward. It has been extended. One end of a connecting rod 39 housed in the head portion 23 is connected to the first piston rod 37, and the spindle rod 26 is connected to the other end of the connecting rod 39. That is, the spindle rod 26 can be moved linearly by the operation of the piston 36.
Further, the second piston rod 38 is connected to the cylinder 35.
It extends into the hole 40a of the casing 40 connected to the rear end of the casing 40. The casing 40 and the cylinder 35 are provided with oil passages 41 and 42 that communicate with the cylinder interior. Reference numeral 43 denotes a first inducer for supplying oil to the oil passages 41 and 42, and is mounted on the casing 40 so as to be relatively rotatable. The first inducer 43 is fixedly attached to a bracket 44 extending from the machine body 20, and is supplied with pressure oil from a hydraulic source (not shown).

Thus, the spindle rod 26, the connecting rod 39, and the first and second piston rods 3
7 and 38 are provided with a continuous liquid passage 45, and this liquid passage 45 communicates with a joint 46 attached to the rear end of the casing 40 through a hole 40a in the casing 40. There is. The joint 46 has a second injector 4 for supplying coolant.
7 is mounted so as to be relatively rotatable. The second injector 47 is fixedly attached to a bracket 48 extending from the first injector 43, and is supplied with coolant from a coolant supply source (not shown).

Note that rotational force is transmitted to the pulley 33 from a drive source (not shown) via a belt (not shown). In addition, the outer cylinder spindle 2
2 is provided with a stopper (not shown) that restricts the rotation range of the rotary holder 27.

Further, a balancer 49 is attached to the rotary holder 27 to balance the rotation.

With this configuration, when the outer cylinder spindle 22 rotates due to the rotation of the pulley 33, the spindle rod 26 connected to the outer cylinder spindle 22 by serration, the rotary holder 27 screwed to the spindle rod 26, and the cylinder connected to the rear part of the outer cylinder spindle 22. 35, the casing 40, etc. rotate together, and the tool 30 attached to the rotary holder 27 can perform, for example, surface cutting of the inner surface of a hole in a workpiece. At this time, the coolant supply source is driven to the second injector 4.
Coolant is supplied into the liquid passageway 45 through 7. As a result, the coolant is discharged from the front end opening of the spindle rod 26 into the hole of the workpiece, and the cutting surface is effectively cooled.

By the way, since the rotation center (axis O ₂ ) of the rotary holder 27 is eccentric with respect to the rotation center (axis O ₁ ) of the outer cylinder spindle 22, the rotation holder 27
When the tool 30 rotates, the position of the tool 30 changes. Therefore, as shown in FIG. 3, the rotation range of the rotary holder 27 is set to 120°, and the cutting edge of the tool 30 is moved to a position a inside the current hole inner surface _F1 of the workpiece.
Set it to . Now, due to the actuation of the piston 36 in the cylinder 35, the spindle rod 26
When the rotary holder 27 is rotated, the cutting edge of the tool 30 is aligned with the axis O ₂ of the rotary holder 27.
When centered at
Position b is reached by 120° rotation of 7. Therefore, the circle including the point b centered on the axis _O1 of the outer cylinder spindle 22 becomes the finished surface _F2 of the hole, and this
The difference F between F ₂ and F ₁ is the amount of cut (depth of cut) of the tool 30. That is, the eccentricity (offset amount) δ between the outer cylinder spindle 22 and the rotating holder 27,
By setting the rotation range of the rotary holder 27 and the original position a of the tool 30 in advance, not only can the cutting depth F of the tool be adjusted arbitrarily, but also the cutting depth F of the tool 30 can be adjusted as desired.
It also becomes possible to insert the material into the processed area.

In the above embodiment, since the balancer 49 is provided on the rotary holder 27, it is possible to absorb the unbalance of the rotation of the outer cylinder spindle 22 caused by offsetting the spindle rod 26 and the rotary holder 27, resulting in a more stable cutting state. will be able to maintain.

In the above embodiment, the spindle rod is inserted into the outer cylinder spindle 22 by spline connection, but if the spindle rod is configured to be unable to rotate relative to the outer cylinder spindle 22 and can move linearly, the connection can be made. The mode is arbitrary, and for example, a combination of a key and a keyway can be used.

Further, the means for linearly moving the spindle rod 26 is not limited to the cylinder mechanism in the above embodiment, but may be replaced by other means such as a rack and pinion mechanism.

Furthermore, it goes without saying that the spindle rod 26 may be connected to its open end with a feed pipe extending to the mounting portion of the tool 30.

(Effects of the invention) As explained above in detail, the invention provides a spindle rod that is eccentrically inserted into the outer cylindrical spindle and a rotary holder that is rotated by the linear movement of the spindle rod. Therefore, while ensuring the requirement to move the tool in the radial direction of the spindle, it is now possible to release coolant forward through the spindle, allowing coolant to be released near the tool regardless of machining depth or hole diameter. This has had the effect of significantly expanding the scope of use of machine tools.

[Brief explanation of drawings]

FIG. 1 is a partially opened perspective view showing the schematic structure of a coolant supply device for a machine tool according to the present invention, FIG. 2 is a sectional view showing its detailed structure, and FIG.
FIG. 4 is an explanatory diagram showing a tool locus of the present coolant supply device, and FIG. 4 is a partially opened perspective view showing the conventional structure of a machine tool to which the present coolant supply device is applied. 22...Outer cylinder spindle, 26...Spindle rod, 27...Rotating holder, 35...Cylinder, 36...Piston, 45...Liquid passage.

Claims (1)

[Scope of utility model registration request] A spindle rod is eccentrically inserted into the outer cylinder spindle so as to be non-rotatable relative to the rod and movable in the axial direction, and inside the front end of the outer cylinder spindle, the rod can be moved in the axial direction by the outer cylinder spindle. A rotary holder for holding a tool is disposed in a state in which the tool is regulated and screwed onto the spindle rod, and a driving means for linearly moving the spindle rod is provided on the rear side of the outer cylindrical spindle. A coolant supply device for a machine tool, characterized in that a coolant supply passage is provided in the machine tool, and the passage is extended to the rear of the outer cylindrical spindle.