JPH0111361Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to the structure of a main shaft portion configured to support a workpiece (workpiece) in a machine tool such as an internal grinder.

(Prior Art) Machine tools have heretofore been known in which a chuck device for gripping a workpiece is opened and closed by moving back and forth a chuck opening/closing member that passes through a main shaft portion. In machine tools with such a structure, it is strongly required to detect whether or not a workpiece is being gripped by the chuck device in terms of automatic control of the machine tool. A method is being taken.

That is, a detection device consisting of a proximity switch or the like is provided near the chuck device to directly detect the movement of the workpiece gripping claws to detect whether or not the workpiece is being gripped, or the movement of the chuck opening/closing member is detected. In some cases, it is possible to detect whether or not a workpiece is being gripped. (For example, see Japanese Utility Model Application Publication No. 57-173907.) However, in the former case, not only is it difficult to accurately detect the movement of the workpiece gripping claws, but also there is a chuck device installed near the chuck device to cool the workpiece being machined. coolant is supplied, making it unsuitable for electrical parts. In the latter case, it becomes necessary to separately provide an interlocking member configured to interlock with the chuck opening/closing member from the chuck opening/closing member to the outside of the main shaft. If this happens, the main shaft will become larger, resulting in seizure of the oil seal, oil leakage, and
Problems such as a complicated structure arise.

(Purpose of the invention) This invention was made in view of the above points.
The purpose of this is to accurately detect the opening and closing of the chuck device (in other words, the presence or absence of gripping a workpiece) without increasing the size or complication of the structure of the main shaft portion.

(Means for achieving the purpose) The present invention, as a means to achieve the above purpose,
A chuck device for gripping a workpiece is disposed at the front end of an outer cylindrical member fixed on a table to pivotally support a rotatably driven cylindrical member. A chuck opening/closing pipe is connected to the work gripping claw of the device and has a flange member at its rear end, and an oil chamber is formed between the flange member and the inner surface of the cylindrical member. The chuck opening/closing pipe is moved back and forth by controlling hydraulic pressure, thereby driving the workpiece gripping claws to open and grip the workpiece, and the chuck opening/closing pipe includes a pipe for opening and closing the chuck. A coolant liquid supply pipe that moves back and forth in conjunction with each other is passed through, and the front end of the coolant liquid supply pipe is adjustable in front and back positions so that the front end opening position can be adjusted to supply coolant to the processing position of the workpiece. An opening position adjustment mechanism having a nozzle is provided, and a mechanism is provided near the rear end of the coolant supply pipe that protrudes from the opening/closing pipe to indirectly control the opening/closing operation of the chuck device by detecting the back and forth movement of the rear end. It is characterized by being equipped with a detection device that detects the

(Function) In the present invention, the following effects can be obtained by the above means.

That is, (1) the front end opening position can be adjusted to the optimum position by the opening position adjustment mechanism provided at the front end of the coolant liquid supply pipe, and the coolant liquid supply pipe moves back and forth in conjunction with the chuck opening/closing pipe. Despite having a moving configuration, there is no need for complicated position adjustment of the detection device that detects the forward and backward movement of the coolant supply pipe.
Coolant liquid is always supplied to the workpiece processing position.

(2) The rear end of the existing coolant supply pipe (protruding from the chuck opening/closing pipe)
The opening/closing operation of the chuck device is accurately detected by the movement of the chuck, and the main shaft does not become larger or more complicated.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

This machine tool is an internal grinder, and has two tables movably placed on the bed, namely:
It includes a work side table 1 and a tool side table 2.

On the work-side table 1, an outer cylinder member 3 constituting a main shaft body is fixed.

Inside the outer cylindrical member 3, the work side table 1 is provided.
A cylindrical member consisting of a boss part 7 of a pulley 5 that is rotationally driven by a motor 4 placed and fixed thereon, and cylindrical shaft parts 8 and 9 that are integrally connected to the boss part 7 and extend forward and backward. 6 is pivotally supported. code 10
is a belt mounted between the motor 4 and the pulley 5.

A chuck device 12 for gripping the workpiece 11 is attached to the front end of the cylindrical member 6 (in other words, the front end of the cylindrical shaft portion 8).

The chuck device 12 includes a holder 13 fixed to the front end of the cylindrical shaft portion 8, and a workpiece gripping claw 14 held by the holder 13 so as to be freely movable and rotatable.
, a diaphragm 15 attached to the holder 13, a workpiece holder 16 fixed to the peripheral edge of the diaphragm 15, and a stopper 17 fixed to the holder 13 to determine the attachment position of the workpiece 11. ing.

The work gripping claw 14 and the work holder 16
are provided alternately at equal intervals on the circumference, three at a time.

The workpiece gripping claw 14 cooperates with the stopper 17 to grip the workpiece 11 when it retreats, and the workpiece holder 16 opens and closes in the direction of arrow A or B in accordance with the expansion and contraction of the diaphragm 15, and when the workpiece holder 16 moves back, it grips the workpiece 11. retain the outer periphery of

Inside the cylindrical member 6 is a chuck opening/closing pipe 18 whose front end is connected to the work gripping claw 14 of the chuck device 12 via an arm 19 and whose rear end is provided with a collar member 20. It is arranged. The chuck opening/closing pipe 18 is connected to the pin 2
1 allows it to rotate together with the cylindrical member 6.

Flange member 2 at the rear end of this chuck opening/closing pipe 18
0 and the inner surface of the cylindrical member 6 (in this embodiment, the inner surface of the pulley boss portion 7 and the cylindrical shaft portion 9), oil chambers 22 and 23 are formed, and the oil pressure to the oil chambers 22 and 23 is By controlling the chuck opening/closing pipe 18, the chuck opening/closing pipe 18 is moved back and forth, and as the chuck opening/closing pipe 18 moves back and forth, the work gripping claws 14, which move forward and backward, are driven to open and grip the work 11. It is configured to be able to do the following. The oil pressure is supplied to the oil chambers 22 and 23 from a hydraulic pipe 25 connected to a bearing 24 that pivotally supports the cylindrical shaft 9 to oil passages 26 and 2 formed in the cylindrical shaft 9.
This is done via 7.

A coolant liquid supply pipe 28 is provided through the chuck opening/closing pipe 18 and is moved back and forth in conjunction with the chuck opening/closing pipe 18. An opening position adjustment mechanism 29 configured to adjust the opening position is provided at the front end of the coolant liquid supply pipe 28. The opening position adjustment mechanism 29 includes a nozzle 30 fitted into the supply pipe 28 so as to be able to move forward and backward to form the opening at the tip of the coolant supply pipe 28, as shown in FIG.
A cap nut 31 having a hole 32 through which the nozzle 30 passes and is screwed onto the tip of the coolant supply pipe 28; 28
It is comprised of an O-ring 34 that engages with a tapered surface 33 formed at the tip. Thus, the nozzle 30 is positioned and fixed at an arbitrary drawer length position by the wedge effect between the tapered surface 33 and the O-ring 34 as the cap nut 31 is tightened. This allows the tip opening of the nozzle 30 (in other words, the front end opening of the coolant supply pipe 28) to
It can be adjusted to a position suitable for supplying coolant to one processing position. Note that the arm 19 provided at the front end of the chuck opening/closing pipe 18
An annular projection 19a is formed in the center of the diaphragm 15. When the projection 19a moves forward and comes into contact with the diaphragm 15, the diaphragm 15 is expanded, and when the projection 19a retreats, the diaphragm 15 exerts its own force. As the coolant supply pipe 28 moves back and forth (in other words, the chuck opening/closing pipe 18 moves back and forth), the diaphragm 15 can expand and contract.

The rear end of the coolant supply pipe 28 is
As shown in FIG. 3, it is rotatably mounted via a bearing 37 to a housing 36 to which a connection pipe 35 for supplying coolant is connected, and the connection pipe 35 and supply pipe 28 are connected within the housing 36. The seal retainer 39 is urged by a spring 38 so as to be pressed against the open end of the supply pipe 28, and is communicated via a floating seat 40. In other words, the housing 36 is isolated from the rotational force of the supply pipe 28.

A reference member 41 is attached to the housing 36 and serves as a reference for detecting the back and forth movement of the coolant liquid supply pipe 28.

On the other hand, a detection device 42 for detecting the back and forth movement of the reference member 41 is mounted on the work side table 1 at a position facing the reference member 41 via a mounting member 43. The detection device 42 includes a front detection switch 42a that detects the forward position of the coolant supply pipe 28 (in other words, the open position of the chuck device 12), and a front detection switch 42a that detects the backward position of the supply pipe 28 (in other words, the open position of the chuck device 12). 12 (closed position)), and a rear detection switch 42b that detects the closed position of 12).
A proximity switch is used.

In addition, in the drawing, reference numeral 44 is a grinding tool, 45 is a rotating shaft for rotating the grinding tool 44, and 46 is a rotating shaft 4.
5, 47 is a motor that drives the rotating shaft 45, 48 is a chuck cover that surrounds the workpiece processing position, 49 is a nozzle that supplies coolant to the outer circumferential side of the workpiece 11, and 50 is connected to the nozzle 49. Supply pipes 51 and 52 are pipes for distributing coolant cast into the table 1, 53 is a cooling air passage, and 54 is a reflection plate that blocks heat from the motor 4, and the chuck cover 4
8 and the supply pipe 50 are both of the split type and are expandable and retractable according to the size of the workpiece 11, and the pipes 51 and 52 for circulating the coolant extend into the workpiece side table 1 below the motor 4. The motor 4 is cooled.

Next, the action of the main shaft portion of the illustrated machine tool will be explained.

When the workpiece 11 is removed, the collar member 20 of the chuck opening/closing pipe 18 is in the chain line position under hydraulic control, and the workpiece gripping claw 14 of the chuck device 12 is in the forward position (in other words, the open position). Further, due to the extension of the diaphragm 15, the workpiece holder 16 is in the open position (in the direction of arrow A). At this time, the detection device 42 detects the forward position of the coolant supply pipe 28 using the front detection switch 42a.

Next, when the workpiece 11 is supplied to the set position by appropriate means, the chuck opening/closing pipe 18 and the coolant supply pipe 28 are retracted by hydraulic control of the oil chambers 22 and 23. At this time, first, the workpiece holder 16 is closed in the direction of arrow B by contraction of the diaphragm 15 to hold the outer circumference of the workpiece 11, and then the workpiece gripping claw 14
moves back and grips the workpiece 11 between it and the stopper 17. When gripping the workpiece is completed, the coolant supply pipe 28 reaches its retraction limit, and its position is detected by the rear detection switch 42b of the detection device 42.

(Effect of the invention) As described above, according to the invention, the coolant liquid supply pipe passing through the chuck opening/closing pipe for opening/closing the chuck device that grips the workpiece is moved forward and backward in conjunction with the chuck opening/closing pipe. Since the opening/closing operation of the chuck device is indirectly detected at the rear end of the coolant supply pipe, the pipe member conventionally used for supplying coolant can be used. This has the practical effect of being able to accurately detect the open/closed state of the chuck device without increasing the size or complicating the structure of the main shaft.

Further, since the opening position adjustment mechanism provided at the front end of the coolant supply pipe allows the front end opening position of the supply pipe to be adjusted as appropriate, the detection device for detecting the forward and backward movement of the coolant supply pipe Another advantage is that coolant can be accurately supplied to the workpiece processing position without requiring complicated positional adjustments.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional plan view showing the main shaft structure of a machine tool according to an embodiment of the present invention, Figure 2 is an enlarged view of the opening position adjustment mechanism, and Figure 3 is an enlarged view of the rear end of the coolant supply pipe. FIG. 1...Table (work side), 3...Outer cylinder member,
6... Cylindrical member, 11... Work, 12... Chuck device, 14... Work gripping claw, 18... Pipe for chuck opening/closing, 20... Flange member, 22, 23
......Oil chamber, 28...Coolant liquid supply pipe,
29...Opening position adjustment mechanism, 30...Nozzle, 3
1... Bag nut, 42... Detection device.

Claims (1)

[Scope of utility model registration request] an outer cylindrical member fixed on a table; a cylindrical member that is rotatably supported within the outer cylindrical member and is rotatably driven with a chuck device for gripping a workpiece disposed at its front end; The front end portion is connected to the work gripping claw of the chuck device, and the rear end portion is provided with a flange member, and an oil chamber is formed between the flange member and the inner surface of the cylindrical member. A chuck opening/closing pipe that is moved back and forth by controlling the oil pressure in the oil chamber to drive the workpiece gripping claws to open and grip the workpiece; The opening position adjustment mechanism is provided with a nozzle that can be moved back and forth at the front end, and by adjusting the position of the nozzle, coolant is supplied to the processing position of the workpiece. and a detection device that indirectly detects the opening/closing operation of the chuck device by detecting the back and forth movement of the rear end portion of the coolant fluid supply pipe protruding from the chuck opening/closing pipe. A main shaft structure of a machine tool, characterized by comprising: