JPH01127205A - Assembly unit of main spindle and tool for machine tool - Google Patents

Abstract

PURPOSE:To properly use with no problem both fixed and rotary tools preventing the fixed tool from deteriorating its accuracy and from generating its vibration by fixedly forcing the fixed tool to be brought into press contact with a fixed outer cylinder end face of a main spindle and the rotary tool to be brought into press contact with a rotary main spindle end face. CONSTITUTION:Forcing an adapted surface 90 of a fixed tool 80 to be brought into press contact with an adapted surface 92 of an end face 26 of a fixed outer cylinder 14, because its key 40 is stopped to a key groove 96 of the fixed tool 80, an unbalanced load is not directly applied acting on a rotary main spindle 10 and bearings 12, and the tool is supported by the fixed outer cylinder 14. When the tool 80 is removed, a clamp rod 50 is extruded against a belleville spring 56, sinking a clamp ball 62 in a recess 66, and a small contour fitting part 88 is opened. A rotary tool 85 forms its small contour fitting part 88 similarly to the fixed tool 80, and forcing an adapted surface 91 to come into press contact with an end face 38 of the rotary main spindle 10 fixing a key 97 by a bolt 95 of the adapted surface 91 corresponding to a key groove 48 of the rotary main spindle 10, it turning effect is transmitted to the rotary tool 85. Accordingly, the tool 85, providing no stopped condition to the fixed outer cylinder 14, is stopped only to the rotary main spindle 10.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a main spindle of a machine tool, and particularly to a main spindle/tool assembly for a machine tool in which both a fixed tool and a rotating tool can be used properly. .

[Prior art] The spindle head of a conventional machine tool has a rotatable machine spindle (rotating spindle) inside a fixed outer cylinder via a bearing, and the inner diameter of this machine spindle contracts toward the far end of the machine tool. It is formed in a tapered shape so that the diameter is increased, so that standard tools for machining centers, etc. can also be used. When a rotary tool is used, the tapered base of the rotary tool is inserted into the machine spindle and clamped, and the rotary tool is rotated by rotating the machine spindle to perform end milling and drilling. Can be processed. On the other hand, fixing tools.

For example, when using a cutting tool, the base of a cutting tool holder that holds the cutting tool is similarly inserted into the machine main shaft and clamped, and the machine main shaft is fixed during use.

[Problems to be solved by the invention] However, in the main spindle of such conventional machine tools,
In particular, when using a fixed tool, the unbalanced load during turning is supported by the tapered surface of the inner diameter of the machine spindle and the bearing, resulting in low rigidity and precision of the support structure of the fixed tool, which reduces the accuracy of turning. There are problems such as generation of vibrations and vibrations. This is especially noticeable when the length of the fixing tool protruding from the spindle head is large, for example during poling processing. Here, in order to improve the support strength when using conventional fixing tools, an angular bearing or the like has been used instead of a ball bearing link as a bearing for one machine's main shaft. Compared to the case where a rotary tool is used, there is a disadvantage that the high-speed rotation of the machine main shaft must be sacrificed when a rotating tool is used. Furthermore, when using such a fixing tool, the machine main shaft (rotating main shaft), which is originally rotatably supported, must be fixed with a strong rotation locking mechanism, which requires a very complex and expensive structure. Become something. Furthermore, the tapered surface of the machine spindle tends to be reduced one-sidedly, which causes a further decrease in turning accuracy.

The present invention was made in view of the problems of the prior art, and its purpose is to improve the performance of the tool not only when using a rotating tool but also when using a stationary tool. The support structure is extremely simple and has good rigidity and precision, and as mentioned above, there is no need to use an inaccurate structure such as supporting the unbalanced load with a bearing when using a fixing tool. To provide a main spindle/tool assembly for a machine tool that does not require sacrificing high speed.

[Means for Solving the Problems] The present invention is intended to achieve such an object, and is directed to a spindle head of a machine tool in which a rotary spindle is rotatably disposed within a fixed outer cylinder. A first locking portion is provided on the outer cylinder, a second locking portion is provided on the rotating main shaft, and a fixing tool is formed with a contact surface that presses against the end surface of the fixed outer cylinder when clamping to the spindle head. , a third locking portion that is locked to the first locking portion is provided, and the rotating tool is provided with a contact surface that presses against the end surface of the rotating spindle when clamped to the spindle head; The fourth locking part is locked to the second locking part.
It has a configuration in which a locking portion is provided.

[Operation 1] With this configuration, when the fixing tool is used, the fixing tool is pressed against the end surface of the fixed outer cylinder, and the fixing tool is pressed against the end surface of the fixed outer cylinder, and the fixing tool is pressed against the fixed outer cylinder end surface, and the fixing tool is pressed against the fixed outer cylinder end surface, and the fixing tool is pressed against the end surface of the fixed outer cylinder, and the fixing tool is The rotation of the tool is also prevented, so that unbalanced loads during turning and the like are less likely to act on the bearings of the rotating main shaft, and most of the load can be borne by the fixed outer cylinder.

On the other hand, when using a rotating tool, the rotating tool is directly supported by the rotating main shaft, and the rotational force of the rotating main shaft is applied to the rotation by the locked state of the second locking part and the fourth locking part. There is no need to reduce the support rigidity of the tool for one rotation by being transmitted to the tool.

[Example] The present invention will be explained below based on embodiments shown in the drawings.

Figures 1 to 3 show the situation when a fixed tool such as a cutting tool is used as the tool, and Figures 4 and 5 show the situation when a rotating tool such as a drill is used as the tool. ing. Here, in FIGS. 1 and 4, the upper half of the figure shows a state in which the tool is clamped, and the lower half shows a state in which the clamp is released.

First, referring to FIG. 1, the reference numeral 10 indicates the rotating main shaft of the spindle head of the machine tool. On the other hand, the base end side of the 0-rotation main shaft 10, which is rotatably supported, ie, the right side in FIG. It can be engaged with an external drive gear 24 through an opening 22 formed in the outer cylinder 14. In this case, since the tool used is a fixed tool, the drive gear 24 is not rotated or is removed from the gear 18.

The fixed outer cylinder 14 includes a lid 2B forming an end face 26 thereof, a central cylinder 30, and a rear part 32 including the opening 22. The lid body 2B is in airtight contact with the outer periphery of the tip end portion of the rotating main shaft 10, that is, the left end portion in FIG. They are on the same page. End face 26
A pair of keys 40 are fixed with bolts 42, and this key 40 has a first key 40 for locking a fixing tool to be described later.
Functions as a locking part. Furthermore, an air injection passage 44 is formed in the lid body 2B for cleaning the inside of the spindle head with compressed air when changing tools, and this air injection passage 44 is a penetrating passage that passes diagonally from the outer circumference to the inner circumference of the rotating spindle lO. Road 4
It is connected to 6. Also refer to Figure 2, the main rotation, axis lO
A pair of key grooves 48 are formed in the end face 38 of the rotor, and the key grooves 48 function as a second locking portion for locking a rotary tool, which will be described later.

A clamp rod 50 for gripping a tool is inserted into the rotating main shaft IO so as to be slidable in the axial direction along its axis, and this clamp rod 50 is fixed from the position of the end face 26 of the substantially fixed outer cylinder 14. It protrudes through the rear cylinder 32 of the outer cylinder 14. A sleeve 52 is disposed between the outer periphery of the distal end of the clamp rod 50 and the inner periphery of the rotating main shaft 10, and this sleeve 52 is prevented from moving in the distal direction by a stepped portion 53 of the rotating main shaft 10, and The rod 50 is slidable in the axial direction relative to the sleeve 52. A large-diameter base 54 is screwed and fixed near the rear end of the clamp rod 50, and a disc spring 5B is interposed between the large-diameter base 54 and the sleeve S2. This disc spring 56 biases the clamp plot 50 toward the proximal end, that is, toward the right in FIG. 1, to the clamp position via the large diameter base 54. Further, a clamp release member 58 such as a hydraulic plunger is opposed to the base end surface of the clamp plot 50 protruding from the fixed outer cylinder 14, and the clamp release member 58 is in a state shown in the lower half of FIG. , move to the left of the diagram to obtain Clan plot 50.
protrudes toward the tip against the biasing force of the disc spring 56,
The tool can be unclamped.

As shown in FIG. 3, a plurality (for example, three) of retainers 60 are formed near the tip of the sleeve 52;
Clamp balls 62 are arranged in each of these holding holes 60. The clamp ball 62 has a diameter larger than the wall thickness of the sleeve ≦2, and the ring 6 attached to the outer periphery of the sleeve 52 prevents it from falling outside the sleeve 52.
It is blocked by 4. On the other hand, a recess 66 is formed on the outer periphery of the clamp rod 50 corresponding to the clamp ball 62, and the recess 66 allows the clamp ball 62 to be inserted therein. It has a tapered surface 68 for pushing out. , Therefore, when the clamp lot 50 is positioned in the proximal direction due to the biasing force of the disc spring 56, the clamp ball 6
2 is pushed out of the sleeve 52 by the tapered surface 6B of the recess 66.

A cutting oil passage 70 is formed to pass through the center of the clamp plot 50 along its axial direction, and this cutting oil passage 70 has a through passage 72 that penetrates in the radial direction at the base end position of the clamp plot 50. An injection path 74 for injecting cutting oil formed in the rear cylinder 32 of the fixed outer cylinder 14 through
is connected to. Reference numeral 76 is a pressure release hole, and 78 is a Holoceratos Frier for sealing.

Reference numeral 80 denotes a fixing tool, which in this embodiment is composed of a cutting tool tip 82 and a cutting tool holder 84 that holds this cutting tool tip 82. The proximal end of the tool holder 84 is formed into a substantially cylindrical shape as shown in FIG.
Continuing thereon, a small-diameter fitting portion 88 is provided. Small diameter insertion part 88
is inserted into the space between the rotational main shaft lO and the sleeve 52, and when the small diameter fitting part 88 is inserted, the back surface formed by the step part 86 is fixed as the abutment surface 90. It is configured to abut on the inner peripheral side portion of the end surface 26 of the outer cylinder 14, that is, the abutment surface indicated by the reference numeral 92. The clamp ball 62 is provided on the inner periphery of the small diameter fitting portion 88.
A V-groove 94 is formed correspondingly to the clamp ball 62 or the slope of the proximal end of the V-groove 94 during clamping, so that the fixing tool 80 (the same applies to rotating tools) is applied with a strong force. The fixing tool 80 is pulled into the main shaft side.
The abutment surface 90 of the main shaft and the abutment surface 92 of the main shaft are brought into pressure contact. On the other hand, a pair of key grooves 96 are formed in the bite holder 84 of the fixing tool 80, corresponding to the pair of keys 40 of the fixed outer cylinder 14, into which the key 4Q, which is the first locking part, is engaged. Third
Functions as a locking part. This prevents the fixing tool 80 from rotating. Reference numeral 81 is an oil passage communicating with the cutting passage 70 of the rotating main shaft 10, and 83 is a discharge port thereof.

In this way, according to this embodiment, when the fixing tool 80 is used, the fixing tool 80 does not have any locking state with respect to the rotating main shaft lO, and the abutting surface 90 of the fixing tool 80 The key 40 of the fixed outer cylinder 14 presses against the contact surface 92 of the end face 26 of the fixed outer cylinder 14 and the key groove 96 of the fixing tool 80
Therefore, the unbalanced load acting on the fixing tool 80 does not directly act on the rotating main shaft 10 and the bearing 12, but is mostly supported by the fixed outer cylinder 14.

Further, since the fixing tool 80 is prevented from rotating due to the locked state between the key 40 and the key groove 96, the fixing tool 80 has high support rigidity and good stationary performance. Therefore, there is no need for a special mechanism for locking the rotation of the rotating main shaft 10 as in the prior art, and a ball bearing suitable for high-speed rotation can be used as the bearing for the rotating main shaft 10. Furthermore, in the past, the fixing tool was also locked to the rotating spindle 10, so when replacing the fixing tool, the rotating spindle IO had to be positioned at a predetermined position in order to lock with the new fixing tool. However, according to this embodiment, the fixing tool 80 is not structured to lock with the rotating main shaft 10;
There is no need to align the O, and therefore it is possible to expedite the work and reduce costs when replacing the fixed tool.

In addition, when removing the fixing tool 80, it is only necessary to make the clamp release member 58 protrude toward the distal end and push the clamp rod 50 toward the distal end against the biasing force of the disc spring 56, whereby the clamp ball 62 is released from the clamp. It sinks into the recess 66 of the rod 50 and opens the small diameter fitting part 88 of the fixing tool 80, which allows the fixing tool 80 to be taken out very easily.

Next, FIGS. 4 and 5 show a state in which a rotary tool is used as the tool. Here, the structure on the spindle side is not completely different from that of the fixed tool described above, so the same parts are indicated by the same symbols and their explanation is omitted. Only the structure on the base end side of the rotating tool is slightly different. It's just a matter of fact. That is, in this embodiment, the rotating tool 85 includes a trill 8f and a collet chuck 89 that holds the trill 87.
Except for the difference in the position of a contact surface 91, which will be described later, the proximal shank side of this rotating tool 85 has a small diameter fitting part 88 with a V-groove 94, and other features as described above. It is formed substantially in the same manner as the proximal shank portion of the fixing tool, so that it can be applied to a so-called ATC (automatic tool change mechanism).

The contact surface 91 of the rotating tool 85 is formed using one back surface of the rotating tool 85 at a position corresponding to the end surface 38 of the rotating main shaft 10 on the tool side. The surface 91 is configured to come into pressure contact with the end surface 38 of the rotational main shaft lO. Further, a contact surface 91 is provided corresponding to a pair of key grooves 48 which are second locking portions of the end surface 3B of the rotation main shaft lO.
A pair of key grooves 93 are formed in the key grooves 93, and a key 97 as a fourth locking portion is fixed to each of the key grooves 93 by a bolt 95. Therefore, this key 97 is the main axis of rotation lO
By being locked in the key groove 4B, the rotational force of the one-rotation main shaft lO is transmitted to the rotating tool 85.

In this way, since the rotating tool 85 is not locked in any way with the fixed outer cylinder 14 and is locked only with the rotating main shaft lO, it can be used without reducing the rigidity of the tool itself.

In the embodiments described above, the clamp rod 50. is used as the tool gripping means. Although the sleeve 52, clamp ball 621, disc spring 56, etc. have been described, the present invention is not limited to this. It goes without saying that various other clamping methods that can be easily devised by those skilled in the art may be used.

Furthermore, the engagement relationship between the key and the keyway between the tool and the spindle in the above embodiment may be reversed, and the positions of the key and the keyway need not be limited to those in the above embodiment. It is sufficient that they are in positions where they can substantially engage with each other, and these modifications are included in the present invention.

[Effect] As explained above, according to the present invention, the fixing tool is brought into pressure contact with the end surface of the fixed outer cylinder of the spindle head, and the rotating tool is brought into pressure contact with the end surface of the rotating main shaft of the spindle head. This has an excellent effect in that both the fixing tools for one rotation can be used properly without any problem, without reducing the precision of the fixing tools or generating vibrations, which have conventionally occurred.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the spindle/tool assembly for a machine tool according to the present invention, particularly when a fixing tool is used, and FIG. FIG. 3 is an exploded perspective view showing the sleeve in FIG. 1, and FIG. 4 is the same as FIG. A sectional view of the position, Figure 5 is the second position when using a rotating tool.
It is an exploded perspective view of the same position as a figure. 10--Rotating main shaft, 14--Fixed outer cylinder 2
6... End face, 38-... End face 40-...
Key, 48--Keyway 80--Fixing tool, 85--Rotating tool 90.91.92
...Contact surface 96--Key groove, 97-...Key agent Patent attorney Yoshiyuki Inaba Figure 3 fS2

Claims (1)

[Claims] (1) In the spindle head of a machine tool in which the rotating main shaft is rotatably arranged inside the fixed outer cylinder, a first locking part is provided on the fixed outer cylinder, and a second locking part is provided on the rotating main shaft, and the The tool is provided with a contact surface that presses against the end surface of the fixed outer cylinder when clamped to the spindle head, and a third locking portion that is locked with the first locking portion, and the rotating tool is provided with a third locking portion that is locked with the first locking portion. , a main spindle/tool for a machine tool, which is provided with a fourth locking part that forms a contact surface that comes into pressure contact with an end face of the rotating main shaft when clamped to the spindle head, and that is locked to the second locking part. assembly.