JP2602514Y2 - Internal grinding machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inner surface grinding machine for grinding an inner surface of a workpiece with a grindstone.

[0002]

2. Description of the Related Art An internal grinding machine is one of devices for performing a grinding process. As shown in FIG. 2, the inner surface grinder rotates both the workpiece 51 and the grindstone 52, and moves the inside of the workpiece 51 to a grindstone 52 having a width smaller than the width of the workpiece in the axial direction of the workpiece. The inner surface of the workpiece 51 is ground by a traverse motion.

By the way, in the case of a workpiece having a machining width longer than the inner diameter of the workpiece and a lateral hole opened, the grinding resistance is reduced at the lateral hole, so that the periphery of the lateral hole is excessively cut off.
The roundness deteriorates or the straightness deteriorates at the side hole. Therefore, conventionally, in such a case, the rotation of the workpiece is slowed to reduce the influence of the side hole.

[0004]

[Problems to be solved by the invention] However, when the rotation of the workpiece is slowed down, if the depth of cut per rotation of the workpiece is the same, the processing efficiency is reduced by the amount of the slowdown, and the processing time is prolonged. There is a problem that becomes.

[0005] As shown in FIG. 2 in particular, in the case of a small-diameter workpiece, the machining width d is long, the grinding wheel shank 54 becomes long, the rigidity at the grinding wheel tip becomes small, and the flow rate of the grinding fluid required for rough grinding is reduced. 3, the grindstone 52 is pressed against the workpiece 51 by the grinding fluid 55 at the time of machining, and the bite of the grindstone 52 is deepened.
The straightness could not be improved sufficiently.

Accordingly, an object of the present invention is to provide an internal grinding machine capable of preventing a decrease in roundness and straightness due to the influence of a side hole of a workpiece without increasing a machining time.

[0007]

According to the present invention, the inner surface is ground.
Holding means for rotatably holding a work having a through hole to be provided and a lateral hole provided in the through hole, the holding means being rotatable about the axis of the through hole as a rotation axis, and the holding means. and the grindstone for grinding a through hole inner surface of the workpiece, the grinding wheel rotating means for rotating the grinding wheel, upon grinding of the workpiece, the
Grinding fluid supply means for supplying a grinding fluid into the through-hole, and the grinding fluid supply means for the workpiece by the grinding fluid supply means so that the flow rate of the grinding fluid during finish grinding is smaller than the flow rate of the grinding fluid during rough grinding . The object is achieved by providing an internal grinding machine with flow rate switching means for switching the flow rate of the grinding fluid supplied into the through-hole .

[0008]

In this internal grinding machine, the flow rate switching means
The flow rate of the grinding fluid supplied into the through hole of the workpiece is switched by the grinding fluid supply means so that the flow rate of the grinding fluid during the finish grinding is smaller than the flow rate of the grinding fluid during the rough grinding.

[0009] By reducing the flow rate of the grinding fluid during finish grinding, biting into the workpiece of the grinding wheel by the grinding fluid is suppressed, roundness of a workpiece having a lateral hole, the straightness direction
Can be up.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an internal grinding machine according to an embodiment of the present invention; FIG. 1 is an explanatory view showing the configuration of an internal grinding machine according to one embodiment of the present invention.

The internal grinding machine of this embodiment has a grinding wheel shaft 11 rotated by a motor (not shown).
A grindstone 13 is attached to the front end of the grinder 1 via a grindstone shank 12. The grinding wheel shaft 11 is moved back and forth in the axial direction by another motor (not shown).

The internal grinding machine has a main shaft 15, which is rotated by a motor 16 via a pulley 17, a belt 18 and a pulley 19. The main shaft 15 is moved back and forth in a direction perpendicular to the axial direction by another motor (not shown).
A cylindrical workpiece 23 is fixed to the tip of the spindle 15 via a spacer 21 and a workpiece fixing claw 22. Some of the workpieces 23 have side holes.

A grinding fluid passage (not shown) is formed at the center of the spindle 15.
5, a grinding fluid supply port 26 of a rotary joint 25 provided at the rear end
Leads to. Further, the inner surface grinding machine is provided with a grinding fluid tank 27.
And the grinding fluid in the grinding fluid tank 27 is supplied to the grinding fluid supply port 2.
6 and a control device 30 for controlling the entire internal grinding machine.

In this embodiment, two systems of supply lines 31 and 32 for the grinding fluid are provided between the pump 28 and the grinding fluid supply port 26.
Is provided. Each of the supply lines 31 and 32 is provided with a flow control valve 33 and 34 and a solenoid valve 35 and 36, respectively. In response to the cutting speed command, the controller 30 sends a rough grinding open signal 37 to the solenoid valve 35 during rough grinding, and sends a finishing open signal 38 to the solenoid valve 36 during finish grinding. . The electromagnetic valve 35 is opened when the rough grinding open signal 37 from the control device 30 is input, and closed at other times.

The solenoid valve 36 is opened when a finishing open signal 38 from the control device 30 is input, and is closed at other times. The flow rate adjusting valve 33 is set to a flow rate for rough grinding, and the flow rate adjusting valve 34 is set to a flow rate for finish grinding that is smaller than the flow rate for rough grinding.

In the internal grinding machine of this embodiment having such a configuration, the workpiece 23 is rotated by the spindle 15 and
The grindstone 13 is rotated by the grindstone shaft 11, and the grindstone 13 is traversed to grind the inner surface of the workpiece 23. Here, when machining the workpiece 23 having a lateral hole, at the time of rough grinding, only the solenoid valve 35 is opened by the rough grinding open signal 37 from the control device 30 and the rough grinding set by the flow rate adjusting valve 33 is performed. Work fluid 2 at the required flow rate
3 inside. On the other hand, at the time of finish grinding, only the solenoid valve 36 is opened by the finishing open signal 38 from the control device 30, and the grinding fluid having the flow rate for finish grinding set by the flow regulating valve 34 is supplied to the inside of the workpiece 23. .

As described above, by reducing the flow rate of the grinding fluid at the time of finish grinding, the grinding fluid is prevented from biting into the workpiece 23 by the grinding fluid, and the roundness and straightness of the workpiece having a lateral hole are reduced. Can be improved. If the flow rate of the grinding fluid in the entire process is simply reduced, the cooling and lubricating properties of the grindstone are impaired, so that the grindstone wears out and the life of the grindstone is shortened. In the present embodiment, by reducing the flow rate only at the time of finish grinding with a small processing load, not only the processing accuracy of the roundness and the straightness can be improved, but also the life of the grinding wheel can be maintained at the same level as before.

Further, since it is not necessary to slow down the rotation of the workpiece, the processing time can be reduced as compared with the conventional case. In the above embodiment, two supply lines 31,
32, the flow rate at the time of rough grinding and the flow rate at the time of finish grinding are switched. However, at the time of rough grinding at a high flow rate, the solenoid valves of both supply lines are opened, and at the time of finish grinding at a low flow rate, one of the supply lines is turned over. Only the solenoid valve may be opened.

Furthermore, the solenoid valve in the supply line for finish grinding with a small flow rate is eliminated, so that the grinding fluid at the flow rate required for finish grinding is always supplied while the pump is operating, and the solenoid valve is turned on during rough grinding. Opening may be performed so that a required amount of grinding fluid is supplied during rough grinding.

[0020]

As described above, according to the present invention, the flow rate of the grinding fluid is switched so that the flow rate of the grinding fluid during finish grinding is smaller than the flow rate of the grinding fluid during rough grinding. Therefore, biting of the grindstone during finish grinding is suppressed, and without prolonging the processing time,
There is an effect that it is possible to prevent a decrease in roundness and straightness due to the influence of the side hole of the workpiece.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a configuration of an internal grinding machine according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining processing by a conventional internal grinding machine.

FIG. 3 is an explanatory view showing a state in which a grinding wheel is pressed against a workpiece by a grinding fluid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Whetstone shaft 13 Whetstone 15 Spindle 23 Workpiece 27 Grinding fluid tank 28 Pump 30 Control device 31, 32 Supply line 33, 34 Flow control valve 35, 36 Solenoid valve

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B24B 5/06 B24B 55/02

Claims (1)

(57) [Scope of request for utility model registration] 1. A through-hole to be internally ground and a hole disposed in the through-hole.
A workpiece having a lateral hole provided therein ,
Holding means for rotatably holding a rotation shaft, a grinding wheel for grinding a through hole inner surface of the workpiece held by the holding means, and grindstone rotating means for rotating the grinding wheel, upon grinding of the workpiece the a grinding fluid supply means for supplying a grinding fluid inside the through hole, so that the flow rate of the grinding liquid is reduced during finish grinding compared to the flow rate of the grinding fluid during rough grinding, the machine tool by the grinding fluid supplying means An internal grinding machine comprising: a flow rate switching unit configured to switch a flow rate of a grinding fluid supplied into the through hole of an object .