JPH04152006A - Tool exchanging hydraulic pressure supply device - Google Patents

Abstract

PURPOSE:To restrain the thermal deformation of a turret to a minimum, and to prevent the leakage of operating liquid from a turning sliding surface by supplying the hydraulic pressure for operating the tool-gripping device of the turret tool post of a machine tool to the tool holder that has been fitted to the turret. CONSTITUTION:A hydraulic pressure supply head 61 is advanced in such a condition that a turret 5 has been divided, so that it is fittedly inserted into a receiving port 42, and the hydraulic pressure is supplied to a tool holder 14a for operating a tool-gripping mechanism. Since the hydraulic pressure is supplied through an external hydraulic pump, even if there is a certain degree of leakage in a turning sliding surface 47, the tool-gripping mechanism can be securely operated. And, the liquid leakage from the supply passage 45b through the turning sliding surface 47 flows into a drain passage 51b, and is returned through a drain pipe 54, thus it does not leak to the outside. Since the pressure inside the passage 51b at that time is nearly equal to the atmospheric pressure, by arranging a seal member 57 between the passage 51b and bearings 16, 17 for supporting a turning tool 15, the leakage of the liquid from the passage 51b to the outside of the turning sliding surface 47 can be prevented.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention provides hydraulic pressure for clamping or unclamping tools to a plurality of tool holders mounted on the turret. This relates to a device for

(Prior Art) A mechanism for clamping or unclamping a tool to a tool holder using hydraulic pressure, such as hydraulic pressure, is known.

When attempting to automatically exchange tools mounted on a turret using such a device, a hydraulic pressure supply device is required that supplies hydraulic pressure only to the tool holder positioned at the tool exchange position.

This type of conventional equipment has a hydraulic circuit with a sealed liquid built into each tool holder mounted on the turret, and the hydraulic pressure in the circuit is mechanically increased to clamp or unclamp the tool. There is a known structure in which hydraulic pressure for tool exchange is supplied through the pivot axis of the turret, and only the tool holder at the tool exchange position is operated by a switching valve.

The former structure operates the tool gripping mechanism of the tool boulder at the tool change position by mechanically pressing a piston or diaphragm exposed from the back of the turret. In order to realize unclamping, it is a condition that the enclosed liquid does not leak.

(Problems to be Solved by the Invention) When a rotary tool such as a drill or a milling cutter is attached to the turret, the following problems occur in the conventional structure as described above.

A tool holder for a rotary tool has a tool shaft that rotates within the tool holder, and a tool gripping mechanism is built into the rotary tool shaft. Therefore, the hydraulic pressure that operates the tool gripping mechanism is
It is necessary to feed it from the turret into the rotating tool shaft. Therefore, a hydraulic passage that passes through the rotating sliding surface must be provided somewhere in the hydraulic circuit, and leakage of liquid from this passage cannot be avoided, making it impossible to use devices with a structure that seals the liquid. .

Even in a structure in which liquid pressure is supplied through the center axis of the turret, outflow of liquid due to the above-mentioned reasons is unavoidable.

When the working fluid is pressurized, it undergoes a considerable temperature rise;
It is supplied to the turret in a heated state. Therefore, in a device that supplies hydraulic pressure to the entire turret and operates only the tool holder at the tool exchange position using a switching valve, a large amount of heat is supplied to the turret due to the supply of hydraulic pressure, and the thermal deformation of the turret 7) There is a possibility that machining errors may occur.

Further, there is a risk that the working fluid leaked from the holder on which the rotary tool is mounted may enter the bearings that support the rotary tool shaft, deteriorating their functions.

Seal members for preventing leakage of liquid from rotating sliding surfaces are available in various structures, but rotary tool shafts rotate at a considerably high speed and are difficult to clamp and unclamp. Due to the relatively high hydraulic pressure required, it is extremely difficult to reduce leakage of working fluid from rotating sliding surfaces to a negligible level.

(Means for Solving the Problems) In the present invention, each tool holder 14a, b has a guide hole 43 whose hydraulic pressure socket 42 is opened on the back surface of the turret 5.
A hydraulic supply head 61 is provided on the member 1 behind the turret 5 and is movable back and forth so as to face the socket 42 of the tool holder 14a that has been rotated to the tool exchange position.
has been established. A check valve 41 is provided in the socket 42, and the hydraulic pressure supply handle 1 is fitted into the socket 42 airtightly, and the check valve 41 is mechanically opened when the hydraulic pressure supply handle 1 is fitted into the socket 42. shall be.

Drain passages 51b are provided on both sides of the supply passage 45b in the axial direction at the portion where the guide holes 43a, b, and c pass through the rotating sliding contact surface 47, and drain passages 51b of each tool holder 14a, b are provided.
The structure is such that the liquid leaked into the turret shaft 1b is collectively discharged by a drain pipe 54 passing through the center of the turret shaft 2.

(Function) With the turret 5 indexed, the hydraulic pressure supply head 61 is advanced and inserted into the socket 42 facing the turret 5, and the hydraulic pressure is applied to the tool holder 14a at the tool exchange position through the hydraulic pressure supply head 61. By supplying the tool, the tool gripping mechanism 49 of the tool holder 14a is operated. Since the hydraulic pressure at this time is supplied only to the tool holder at the tool exchange position, the temperature of the entire turret 5 does not rise, and therefore, thermal deformation of the turret 5 can be minimized.

Further, since the hydraulic pressure for operating the tool gripping mechanism 49 is supplied from a hydraulic pump installed externally, the tool gripping mechanism 49 can be operated reliably even if there is some leakage in the rotating sliding contact surface 47. can.

Furthermore, the liquid leaking from the supply path 45b at the rotating sliding surface 47 flows into the drain channel 51b before leaking out of the rotating sliding surface 47, is returned through the drain pipe 54, and does not leak to the outside. Since the pressure in the drain passage 51b at this time is approximately atmospheric pressure, a seal member 57 is provided between the drain passage 51b and the bearings 16, 17, etc. that support the rotary tool shaft 15.
By arranging this, it is possible to prevent liquid from leaking out of the rotating sliding contact surface 47 from the drain channel 51b.

(Example) An example shown in the drawings will be described below. Fig. 1 is a cross-sectional view of a tower shaft having the structure of the present invention, in which 1 is the casing of the tool post, 2 is the turret shaft supported on the casing by a sliding bearing 3.4, and 5 is the tip of the turret shaft 2. A fixed turret, 6 a gear fixed to the rear end of the turret shaft 2, 7 a talent indexing motor, 8 a gear train connecting the talent indexing motor 7 and the gear 6 at the rear end of the turret shaft. be.

11 is a clamp piston that moves left and right in the figure; 12 is a ring that transmits the left and right movement of the clamp piston 11 to the turret shaft 2; 13 is a coupling provided between the back surface of the tower shaft 11 and the front surface of the casing l; When the clamp piston 12 moves to the left in the drawing, the coupling 13 is opened and the talleft 5 becomes ready for indexing. After the tallft 5 is indexed, by moving the clamp piston 11 to the right in the drawing, the clamping 13 are fitted, and the taleft 5 is fixed to the casing 1.

14a and 14b are tool holders attached to the tower shaft 5, 14a is a straight holder, and 14b is an L-shaped holder. 15 has bearings 16 and 17 on the holders 14a and 14b.
The rotary tool shaft is supported by Straight holder 14
A driven bevel gear 18 is fixed to the base end of the rotary tool shaft a. A transmission shaft 19 to which a driven bevel gear 18 is fixed at the base end is pivotally supported on the one-sided holder 14b, and the rotation of this transmission shaft is transmitted to the rotary tool shaft 15 via a bevel gear pair 20 and a spur gear pair 21. has been done.

25 is a drive shaft supported by bearings 26 and 27 on the turret shaft 2; 28 is a drive bevel gear fixed to the tip of the drive shaft 25;
29 is a pulley fixed to the rear end of the drive shaft 25. The drive bevel gear 28 meshes with the driven bevel gears 18 of all the rotary tool holders mounted on the taleft 5, and
9 is driven by a belt transmission by a tool drive motor (not shown).

Reference numeral 31 denotes a tool exchange head, and the base body 3 rotates 180 degrees around a central axis P that forms an angle of 45 degrees with respect to the turret axis 2.
2, and the base body has two grippers 33a and 33b extending in a direction of 45 degrees with respect to the central axis P thereof.

One gripper 33a extends in the axial direction of the towerft 5 to grip a tool on the straight holder 14a on the turret 5, and the other gripper 33b faces inward in the radial direction of the towerft 5 to grip a tool on the L-shaped holder 14b. There is. The directions of both glyph pads 33a and 33b are mutually converted by rotation of the base body 32.

Next, the hydraulic pressure supply device of the present invention will be explained.

A socket 42 equipped with a check valve 41 is opened at the back of the shaft 5 at each tool holder mounting portion.

The hydraulic pressure supplied from the receptacle 42 is transmitted through a guide hole 43a provided in the taleft 5, a supply side circumferential groove 45a provided in the fitting surface 44 of the tool holders 14a, 14b, and a guide hole passing through the sleeve 46 of the tool holders 14a, 14b. 43b, a supply side circumferential groove 45b provided in the rotating sliding contact surface 47 between the rotating tool shaft 15 and the sleeve 46, and a guide hole 43c provided in the rotating tool shaft 15 to be guided into the rotating tool shaft 15 and built-in. The tool gripping collet 49 is operated by moving the piston 48.

In the figure, the guide holes 43a to C and the supply-side circumferential grooves 45a, b are provided for 2 m so that the reciprocating movement of the piston 48 is performed by hydraulic pressure, and there are two sockets 42 in the direction perpendicular to the plane of the figure. They are placed side by side. However, in the case of a type in which the tool is clamped by a pin or pushing force of the tool, it is sufficient to guide only the hydraulic pressure for unclamping to the rotary tool shaft 15, and the supply side circumference of the guide hole 43a or C1 is One set of the grooves 45a, b and the socket 42 is sufficient.

supply side circumferential groove 45a of the fitting surface 44 and the rotating sliding contact surface 47;
Drain side circumferential grooves 51a and 51b are provided on both sides of 45b, and drain holes 52a to 52C that communicate with these grooves pass through the sleeve 46 of the tool holder, the taleft 5, and the cover plate 53 fixed to the front surface of the taleft 5. It is provided. The tip of a drain pipe 54 passing through the center of the drive shaft 25 is fixed at the center inside the cover plate 53, and the guide hole 52c of the cover plate communicates with this pipe 54. A rear end of the drain pipe 54 is communicated with a drain hose 56 via a rotary joint 55.

A seal member 57 is disposed further outside the drain-side circumferential groove 51b of the rotating sliding contact surface 47, and bearings 16 and 17 that support the rotary tool shaft 15 are disposed further outside of the seal member 57.

A coupler 61, which is airtightly fitted into the socket 42, is attached to the casing 1 at a position opposite to the socket 42 connected to the guide holes 43b and 43c of the tool holder indexed to the tool exchange position, and is movable forward and backward by a cylinder 62. , this coupler 61
Hydraulic pressure from a pump (not shown) is supplied via a hose 63.

When exchanging tools, position the tool holder 14a with the tool to be exchanged at the tool exchange position, operate the cylinder 62, insert the coupler 61 into the socket 42 that has been rotated to the tool exchange position, Supplying hydraulic pressure into the rotary tool shaft 15 of the tool holder 14a through the coupler 61,
Operate the tool gripping mechanism. At this time, the working fluid leaked from the fitting surface 44 of the tool holder and the rotating sliding contact surface 47 between the rotary tool shaft and the sleeve is drained into the drain side circumferential groove 51'.
a, 51b, and is discharged through the drain holes 52a to 52C and the drain pipe 54.

Since the pressure in the drain side circumferential groove 51b of the rotating sliding contact surface 47 is approximately atmospheric pressure, the high pressure in the supply side circumferential groove 45b does not act on the sealing member 57, and therefore the operation is performed via the sealing member 57. There is no risk of liquid leaking.

(Effects of the Invention) According to the structure of the present invention described above, the hydraulic pressure for operating the tool gripping device can be supplied from the outside to the tool holder mounted on the turret. Even when a rotary tool is used, the hydraulic pressure for the tool gripping device does not leak to the outside. Furthermore, since hydraulic pressure is supplied only to the tool holder at the tool exchange position, the amount of heat given to the turret is small, and thermal deformation of the turret can be minimized.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which FIG. 1 is a sectional view of a turret, and FIG. 2 is an enlarged sectional view of a portion of the turret to which a straight holder is attached. In the figure, casing 5: Turret 14a Nistrade holder 14b: L-shaped holder 15:
Rotary tool shaft 42: Socket 43 (a, b, c)
: Guide hole 47: Rotating sliding contact surface 49: Drain side circumferential groove 54 of collet 51b double rotating sliding contact surface: Drain pipe 59: Seal member 61: Coupler

Claims (2)

[Claims] (1) Multiple tool holders (
The guide holes (43a, b, c) for supplying hydraulic pressure for operating the tool gripping mechanism (49) of 14a, b) are individually provided for each tool holder, and the guide holes (43a, b, c) are individually provided for each tool holder. )
is opened in a socket (42) arranged on the same circumference on the back of the turret (5), and is placed in the socket (42) facing the socket (42) connected to the tool holder (14a) which has been rotated to the tool exchange position. A hydraulic pressure supply head (61) fitted into the tool holder (1) is provided to move forward and backward, and a working fluid is supplied from the outside via the hydraulic pressure supply head (61) to the tool holder (1) rotated to the tool exchange position.
A hydraulic pressure supply device for tool changing, characterized in that it supplies only to 4a). (2) In a turret (5) equipped with a tool holder (14a, b) for a rotary tool, the supply path of the hydraulic pressure supply device according to claim 1 is connected to the rotating sliding contact surface (47) of the rotary tool shaft (15). A drain flow path (51b) is provided on both sides of the portion (45b) that passes through the
This drain flow path (51b) is connected to the turret shaft (2).
The hydraulic pressure supply device for tool changing according to claim 1, characterized in that the hydraulic pressure supply device for tool changing is connected to a drain pipe (54) disposed at the center of the drain pipe (54).