JPH0314287Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a grinding machine that grinds a roller-shaped (cylindrical, conical, cylindrical, etc.) workpiece from heavy grinding to mirror finish.

[Conventional technology]

A method of grinding by bringing a rotating whetstone into contact with the circumferential surface of a rotating roller-shaped material to be ground and running the grindstone between both ends of the material while maintaining this contact state has already been proposed in Japanese Patent Publication No. 51-46318. It is known from the publication no.

[Problem that the invention attempts to solve]

A movable and adjustable weight is provided on a base material that swings like a seesaw, and the weight of this weight brings the grindstone into pressure contact with the material to be ground.

According to this pressure welding method, when the protrusion on the circumferential surface of the material to be ground faces the grinding wheel, the grinding wheel is pushed up, and furthermore, the pushing up mentioned above occurs suddenly due to the high speed rotation of the material to be ground, creating a strong upward force. When the force is attenuated, the weight causes the grinding wheel to fall, and as it descends, the material to be ground collides with the grinding wheel, causing the grinding wheel to repeat the movement of rising again.

As a result, a hopping phenomenon occurred in the grinding wheel, making it impossible to obtain roundness, and there was a problem that heavy grinding was not possible.

Further, since there is a considerable distance between the fulcrum of the base material and the drive spindle of the grinding wheel, a slight vibration on the fulcrum side will be greatly magnified on the spindle side.

As a result, vibrations occur in the grinding wheel (especially noticeable as the weight is moved closer to the spindle), making it impossible to obtain a good mirror surface (surface roughness), and the problem is that the fulcrum part and strong structure must be made. It was hot.

Furthermore, the pressure applied by moving the weight is only a rough guide, and setting the pressure requires a high level of skill (because numerical control is not possible), and there is also the problem that the pressure changes due to wear of the grindstone.

In addition, raising the grinding wheel when attaching and removing the material to be ground requires retracting the weight to the rear of the fulcrum, which is time-consuming and causes a significant drop in efficiency.

[Means for solving problems]

In order to solve the above problems, this invention provides a slider that supports a spindle with a drive function and a grindstone at the lower end on a reciprocating table so as to be able to move up and down, and also has a connection that has a weight on the slider that balances the weight of the slider. The members are connected, and a drive device for lifting the weight having a variable clutch is provided, and a lock device is provided to stop the slider from sliding at a predetermined position with respect to the carriage.

[Effect]

After the workpiece is held by the rotary chuck and the tail stock, the workpiece is rotated by the drive of the rotary chuck.

The grindstone is rotated by the drive of the spindle, and the drive device pulls up a weight to lower the slider, so that it is in pressure contact with the material to be ground.

On the other hand, a carriage having a slider reciprocates between both ends of the material to be ground.

As a result, the peripheral surface of the material to be ground is ground and mirror-ground.

The contact force of the grindstone can be set by adjusting a variable clutch that reduces the weight as the weight rises.

Also, if the slider is stopped by a locking device, heavy grinding can be performed.

〔Example〕

In the figure, 1 is a bed, and at both ends of the bed 1 there is a rotary chuck 2 of a headstock that supports and rotates one end of the workpiece A, and a rotating chuck 2 that rotatably supports the other end of the workpiece A. A tail stock 3 is provided.

Further, on the bed 1, a reciprocating table 4 that moves forward and backward in parallel with the material to be ground A is provided.

The above-mentioned carriage 4 is guided by a rail 5 with a sliding surface provided between both ends of the bed 1, and a male screw 7 is screwed into a female screw 6 supported on the carriage 4, and a motor (not shown) is provided. ), the male screw 7 is reversibly driven to slide back and forth.

Furthermore, the above-mentioned carriage 4 is provided with a slider 8 that can be raised and lowered.

In the illustrated case, the slider 8 has vertical dovetail grooves 9 with sliding surfaces on both sides of the front surface of the carriage 4.
A protrusion 10 of the slider 8 is slidably fitted into this dovetail groove 9.

Further, a spindle 11 with a drive function is supported on the slider 8, and a grindstone 12 is attached to the lower end of the spindle 11 to bring its plate surface into contact with the circumferential surface of the material A to be ground.

The above-mentioned grindstone 12 is detachable from the spindle 11, and can be exchanged for heavy grinding or mirror grinding.

In the illustrated case, the drive function of the spindle 11 is achieved by providing a vertically elongated window 13 on the front wall of the hollow carriage 4, passing through the window 13 an installation seat 14 extending from the slider 8; In this embodiment, the belt 18 is passed between the pulley 16 of the motor 15 and the pulley 17 of the spindle 11, which are installed in the motor 15, but other driving methods may be used.

Further, the slider 8 is connected to the other end of a connecting member 20 having a weight 19 at one end that balances the weight of the slider 8 side.

In the case shown in the figure, the above-mentioned weights 19 are provided on two parallel connecting members 20 to ensure smooth elevation and descent of the slider 8, and the above-mentioned weights 19 are pivotally supported on rails 21. The rotor 22 is brought into contact with the weight 19 to stop the weight 19 from swinging and to guide it smoothly.

Reference numeral 23 denotes a drive device equipped with a variable clutch 24 that lifts up the weight 19 so as to apply a desired pressing force to the grindstone 12.

In the illustrated case, the drive device 23 meshes the timing belt of the connecting member 20 with a pair of front and rear first gears 25 and second gears 26 that are pivotally supported in the carriage 4, and connects a timing pulley from a motor 27 to the timing belt. A main shaft 29 having a variable clutch 24 such as a powder clutch is driven through a transmission mechanism 28 consisting of a timing belt stretched between timing pulleys, and a gear 30 provided at both ends of the main shaft 29 and a second gear 26 provided on the shaft. The second gear 26 is driven by meshing with the gear 31, which is located at the top, and the weight 19 is pulled up.
The weight 19 may be raised using other methods.

At this time, as shown in the figure, an electromagnetic brake 33 is provided in the middle of the main shaft 29, and when the electromagnetic brake 33 is activated during a power outage, etc., the slider 8 is prevented from rising rapidly.

Note that the pressure applied to the grindstone 12 is the same as that of the weight 1.
9 acts, and the weight reduction can be freely set by adjusting the variable clutch 24.

Numeral 32 is a locking device that stops the slider 8 from sliding at a predetermined position relative to the carriage 4 during heavy grinding.

The above-mentioned locking device 32 is connected to the carriage 4 in the illustrated case.
A braking member 35 having a large frictional resistance is brought into pressure contact with the slider 8 by the expansion action of a cylinder 34 attached to the slider 8.

Note that the weight of the weight 19 is equal to or slightly heavier than the weight of the slider 8 side.

〔effect〕

As described above, according to the grinding machine according to this invention, the weight is raised by operating the drive device, and
Since the reduced weight of the weight set by the variable clutch acts on the grinding wheel as a pressing force, various required pressing forces can be easily and quickly obtained by operating the clutch, and it can also be used for long periods like a see-saw type. As the grindstone wears out over time, changes in the pressing force due to gradual weight reduction of the grindstone can be eliminated.

In addition, a slider is provided on the front of the carriage, and a spindle with a grinding wheel is supported on this slider, so that the spindle and slider form an integral structure.
Moreover, the center of the grindstone can be brought extremely close to the front of the carriage.

For this reason, there are problems such as the problem of uneven grinding due to the absence of chatter due to the inertial fulcrum structure as in the case of a seesaw type, and a structure where there is a considerable distance between the grinding wheel and the fulcrum, and a slight vibration between the inertial fulcrum and the grinding wheel. As a result, when the grinding wheel reaches the edge of the machine to be ground and a part of the grinding wheel protrudes from the edge of the material to be ground, the grinding wheel becomes tilted and the edge of the material to be ground is enlarged. The dressing action, in which the surface of the grindstone is roughened at the edge, is repeated each time the grindstone reaches both ends of the workpiece, and the roughened grindstone may scratch the mirror surface or sag the corners of the workpiece. The problem is that the accuracy of cylindricity (undulation) deteriorates, and if a strong pressing force is applied to the whetstone, the above problems become more noticeable, so if a weak pressing force is applied, the polishing time will be significantly longer, and It is possible to eliminate the problem of increased wear of the grindstone.

Furthermore, since the slider can be stopped from sliding by a locking device, it is possible to perform both mirror surface grinding work and perfect circular grinding work with one machine.

In addition, even if the grinding wheel wears out sequentially, the initial point of contact between the workpiece and the grinding wheel does not change sequentially as in the case of a seesaw type, so the contact setting position of the grinding wheel is always constant, resulting in stable surface roughness. At the same time, it is possible to eliminate the problem of having to make corrections each time the contact point changes.

[Brief explanation of the drawing]

Figure 1 is a plan view of the grinding machine according to this invention, Figure 2
The figure is a partially cutaway side view of the same as above, Figure 3 is an enlarged longitudinal side view showing the main parts of the same as above, Figure 4 is a sectional view taken along the line of Figure 3, Figure 5 is a cross-sectional plan view, and Figure 6 1 is a cross-sectional plan view of the locking device; FIG. 1...Bed, 2...Chuck, 3...Tail stock, 4...Mountain carriage, 8...Slider, 11
... Spindle, 12 ... Grindstone, 15 ... Motor, 16, 17 ... Pulley, 18 ... Belt, 1
9... Weight, 20... Connection member, 23... Drive device, 24... Variable clutch, 32... Lock device.

Claims (1)

[Scope of utility model registration request] In the above-mentioned method, the material to be ground is rotated and the plate surface of a rotary whetstone provided on a carriage that slides back and forth along the material to be ground is brought into contact with the circumferential surface of the material to be ground. A slider bearing a spindle with a drive function having a grindstone at the lower end is mounted on the reciprocating table so as to be able to move up and down, and a connecting member having a weight that balances the weight of the slider is connected to the slider, and a weight lifting member having a variable clutch is connected to the slider. 1. A grinding machine characterized by being provided with a drive device for the slider and a locking device for stopping the sliding of the slider at a predetermined position relative to the carriage.