JPS5852788B2 - Toy Shiguruma Seikei Sochi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for shaping a grinding wheel such as a cubic boron nitride grinding wheel, and its purpose is to form the grinding surface of the grinding wheel with high precision and efficiency (truing). and dressing.

Conventionally, when shaping a grinding wheel with a cubic boron nitride abrasive grain layer fixed to the outer periphery of a base ring by truing and dressing, first, a rod-shaped truing tool embedded with diamond abrasive grains is fixed on a table, for example, and the grinding wheel is The outer periphery of the grinding wheel was trued by traversing the table while rotating the table so that the peripheral speed was approximately 27771/sec.

However, the peripheral speed of the grinding wheel during normal grinding work is 40 m/
It has been experimentally found that if the above-mentioned truing is performed at this circumferential speed, large vibrations will occur in the truing tool, making it impossible to perform highly accurate truing work.

Therefore, it has been required to perform highly accurate truing work on the grinding wheel at a normal circumferential speed of the grinding wheel.

Furthermore, after truing the grinding wheel, the worker presses a bar-shaped dressing tool containing alumina abrasive grains onto the outer periphery of the grinding wheel to dress the wheel, but this poses the problem of extremely poor safety and work efficiency. Ta.

In order to solve these conventional problems, the present invention installs a truing wheel and a dressing wheel coaxially for shaping the outer periphery of the grinding wheel, and rotates the truing wheel so as to reduce the peripheral speed relative to the grinding wheel. It is characterized by

Embodiments of the present invention will be described below based on the drawings.

First, in FIG. 1, reference numeral 1 denotes a base. A grindstone 2 is placed on the base 1, and a grinding wheel 4 is fixed to one end of a whetstone shaft 3 rotatably supported on the whetstone 2. ing.

This grinding wheel 4 has a structure in which abrasive grains 6 made of a hard material such as cubic boron nitride are fixed to the outer periphery of a metal base ring 5 (see FIG. 3) with a binder made of resin or metal. .

A drive motor 7 fixed to the grindstone head 2 is rotatably connected to the other end of the grindstone shaft 3 via a transmission belt 8.

In addition, a movable table 1 is attached to the base 10 fixed on the base 1.
1 is slidably mounted in a direction parallel to the grinding surface of the grinding wheel 4, and this movable table 11 is given traverse feed by a fluid pressure cylinder device 12 as a traverse device mounted on the base 10. There is.

A feed base 13 is mounted on the movable base 11 so as to be slidable in a direction perpendicular to the grinding surface of the grinding wheel, and one end of a feed screw shaft 14 rotatably supported on the movable base 11 is screwed into this feed base 13. are doing.

Further, as shown in FIG. 2, at the other end of the feed screw shaft 14, there are a forward feed applying device 50 for advancing the feed table 13 toward the grinding wheel 4 and a backward feed applying device 60 for retracting the feed table 13. operably connected.

To explain the feed applying devices 50 and 60, first, pinion gears 51 and 61 are rotatably supported on the feed screw shaft 14, and rack pars 53 and 63, which are moved forward and backward by cylinder devices 52 and 62, are engaged with this gear 5L61, respectively. has been done.

Rotating member 5 integrally fixed to pinion gears 51, 61
Ratchet wheels 55 and 65 are pivotally supported on 4.64 and are opposed to each other so as to engage with ratchet wheels 56 and 66 wedged on the feed screw shaft 14.

However, the directions in which the ratchets 55 and 65 engage with the ratchet wheels 56 and 66 are opposite to each other.

The forward amount given to the feed table 13 by the forward feed applying device is larger than the backward amount given by the backward feed applying device 60 by the amount of feed of the truing wheel 19 to the grinding wheel 4 for truing.

A support stand 16 is integrally fixed to the feed stand 13, a drive shaft 17 parallel to the grinding surface of the grinding wheel is rotatably supported on the support stand 16, and a drive motor 18 fixed to the support stand 16 is rotatably supported. Rotationally connected to.

This drive shaft 17 has a truing wheel 1 for truing and dressing the grinding surface of the grinding wheel 4, respectively.
9 and a dressing wheel 20 are fixedly spaced apart from each other by a predetermined distance.

The truing wheel 19 has a diamond abrasive layer fixed to the outer periphery of a metal base ring, while the dressing wheel 20 is made of hard metal such as carbon steel or hardened steel.

The outer diameters of both cars 19 and 20 are finished to be the same diameter.

Note that grooves may be carved at appropriate intervals on the outer periphery of the dressing wheel 20.

Furthermore, in FIG. 3, reference numeral 24 denotes a device for supplying a dressing liquid DS, which will be described later, between the grinding wheel 4 and the dressing wheel 20 when dressing the outer periphery of the grinding wheel 4. This dressing liquid supplying device 24 will be explained below.

Reference numeral 25 denotes a nozzle arranged close to the grinding surface of the grinding wheel 4, and this nozzle 25 is fixed to the grinding wheel head 2 via a support bracket (not shown).

26 is a tank in which the dressing liquid DS is stored, and this dressing liquid DS is, for example, a dressing abrasive grain G (about 100 μm in diameter) such as alumina or silicon carbide.
It is mixed at a ratio of 1 kg to 20 J of grinding fluid.

An introduction pipe 27 is connected between the tank 26 and the nozzle 25, and the dressing liquid DS is spouted from the nozzle 25 by the operation of the pump P by the drive motor M.

Reference numeral 28 denotes a flow rate control valve that is provided in the middle of the introduction pipe 27 and adjusts the flow rate of the dressing liquid DS.

Reference numeral 29 denotes a stirring device for uniformly mixing the grinding fluid and the dressing abrasive grains G, which is composed of a drive motor 30 fixedly installed in the tank 26 and a stirring blade 31 connected to the motor 30.

Next, the oscillation mechanism 40 that oscillates the grinding wheel 4 in order to uniformly dress the grinding wheel 4 will be described.

First, the grindstone head 2 has a constant pressure support 41 and a variable pressure support 42.
are fixed concentrically with the grindstone shaft 3 and facing each other.

This constant pressure support 41 has a large diameter stepped portion 4 formed on the grinding wheel 3.
3 has a pressure chamber 44 between its one side 43a and the support 41.
It is loosely fitted to the variable voltage support 42, and is also loosely fitted to the variable voltage support 42.

A plurality of concave pressure pockets 45 are formed in the bottom of the variable pressure support 42 facing the other side surface 43b of the large-diameter stepped portion 43. A periodically fluctuating pressure fluid vP is supplied through a throttle 46 provided at the tip thereof, while a constant pressure fluid CP is supplied to the pressure chamber 44.

Next, the operation of the above configuration will be explained based on the electric circuit shown in FIG.

First, the grinding wheel 4 has a circumferential speed of approximately 45 m/min by the drive motor 7.
It is rotationally driven by s.

Then, when the grinding wheel shaping command is issued, the truing wheel 1
9 and the dressing wheel 20 are driven by the drive motor 18 at approximately 15 m/s in the direction of reducing the relative circumferential speed with the grinding wheel 4.
It is rotated at a circumferential speed of .

Furthermore, the contact 80a is closed, and the relay CR1 is energized, so that the cylinder device 5 of the forward feed applying device 50 in FIG.
2 operates, whereby the pinion gear 51 is rotated as the rack par 53 advances and retreats, and the feed screw shaft 14 is rotated in the forward direction via the rotating member 54, ratchet 55, and ratchet wheel 56.

As a result, the support stand 16 moves forward toward the grinding wheel 4, and the truing wheel 19 moves from the original position shown in FIG. 1 toward the grinding wheel 4 to a position (see FIG. It is fed to a position It) indicated by a virtual line.

Subsequently, the moving table 11 and the supporting table 16 are moved to the position 11 indicated by the imaginary line in FIG.
The grinding wheel 4 is reciprocated between .degree.

When the moving table 11 reciprocates and returns to its original position in this way,
A truing completion signal is sent, contact 81b is opened, relay CRI is deenergized, contact 81a is closed, and relay CR2 is energized.

The drive motor 18 is rotated at a reduced speed by this energization of the relay CR2, whereby the truing wheel 19 and the dressing wheel 20 are decelerated to a circumferential speed of approximately 0.33 m/s.

Based on this deceleration, the cylinder device 12 is operated and the support base 16 is traversed rightward from the state shown in FIG. 1, and as a result, the outer periphery of the dressing wheel 20 is processed by the grinding wheel 4.

Thereafter, the dressing wheel 20 is moved to the grinding wheel 4 as shown in FIG.
When they are aligned in contact with each other, the contact 82b is opened, the relay CR2 is deenergized, and the operation of the cylinder device 12 is stopped.

At the same time, the contact 82a is closed and the relay CR3 is energized, which activates the cylinder device 62 of the backward feed applying device 60 to move the rack par 63 forward and backward, and the feed screw shaft is moved through the ratchet 65 and the ratchet wheel 66. 14
is rotated backwards.

This reverse rotation of the feed screw shaft 14 causes the dressing wheel 20 to
is retracted by a minute amount to a position where a gap t (for example, 50 μm) of a desired size smaller than the diameter of the dressing abrasive grains G is formed between it and the grinding wheel 4, as shown in FIG.

As the dressing wheel 20 moves backward, the drive motor 18
is rotated at an increased speed to the initial state, and the dressing wheel rotates at the circumferential speed of 15 m/s.

At the same time, the drive motor 30 operates, and the dressing liquid DS in the tank 26 is stirred by the stirring blades 31, and is sucked into the introduction pipe 27 by the operation of the pump P.

Then, the dressing liquid DS whose flow rate is adjusted by the flow rate adjustment valve 28 is supplied to the gap t through the nozzle 25.

As a result, the abrasive grains G in the dressing liquid DS have a gap t
While passing through the abrasive wheel 4, the abrasive particles are sprayed onto the bonding agent of the grinding wheel 4 to scrape it off, causing the abrasive grains to protrude from the bonding agent and dressing the grinding wheel 4.

Further, at the same time as the above-mentioned pump P operates, the variable pressure fluid VP
is supplied into the pressure pocket 45 of the variable pressure support 42 via the throttle 46, so a static pressure corresponding to the fluctuating pressure of the fluctuating pressure fluid vP is generated in the pressure pocket 45. The grinding wheel shaft 3 is a pressure chamber 4 of a constant pressure support 41
4 is oscillated in the axial direction against the pressure of constant pressure fluid CP supplied to CP.

Therefore, during the above-mentioned dressing, the grinding wheel 4 oscillates, thereby uniformly dressing the outer periphery of the grinding wheel 4.

After the dressing work is completed, the cylinder device 1
2, the support base 16 is traversed to the left, and the dressing wheel 20 and the truing wheel 19 return to their original positions as shown in FIG. is deenergized and the shaping of the grinding wheel 4 is completed.

In the above embodiment, a ratchet feeding mechanism is connected to the feed screw shaft 14 as a device for advancing and retracting the feed table 13, but a pulse motor is attached to the moving table 11 and connected to the feed screw shaft 14, and this pulse motor The feed base 13 may be moved forward and backward by forward and reverse rotation.

Further, in the above embodiment, the support stand 16 is movable in parallel and perpendicular directions to the grinding surface of the grinding wheel, but the grindstone head 2 may be movable in both of these directions.

Furthermore, in order to perform dressing with free abrasive grains as in the above embodiment, it is not necessary to move the dressing wheel 20 backward relative to the grinding wheel 4 so that a gap is formed between the dressing wheel 20 and the grinding wheel 4. However, dressing may be performed with the amount of retraction set to zero and the gap remaining at zero.

As described above, the truing wheel and the dressing wheel are rotatably supported coaxially on the +3 support base of the present invention, and are rotationally driven so as to reduce the relative circumferential speed with the grinding wheel to be shaped, so that the outer circumference of the grinding wheel is When truing with a truing wheel, the support base is moved relatively forward toward the grinding wheel, and when dressing after truing, the dressing wheel is aligned with the grinding wheel and then the dressing is placed between the dressing wheel and the grinding wheel. Because the structure is designed to supply abrasive grains, high-precision truing can be performed without vibration during truing, and free abrasive grains are automatically supplied, so dressing does not have to be done manually. It is not necessary, safety,
This has the advantage of greatly improving work efficiency.

Further, since the present invention has a structure in which the truing car and the dressing car are arranged coaxially on the support base, the truing car and the dressing car can be arranged close to each other, and the truing car and the dressing car can be used in a common device. It can be rotated and the device that moves it relative to the grinding wheel can also be shared.
This has the advantage that the configuration is simple.

[Brief explanation of drawings]

Fig. 1 is a partially sectional plan view of an embodiment of the present invention, Fig. 2 is an enlarged cross-sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is a section between the grinding wheel and the dressing wheel. 4 and 5 are diagrams showing the positional relationship of the truing wheel and dressing wheel with respect to the grinding wheel, and FIG. 6 is a control electrical circuit diagram. . 2... Grinding wheel head, 4... Grinding wheel, 6...
...Cubic boron nitride abrasive grain layer, 12...Fluid pressure cylinder device (traverse device), 16...
Support stand, 1T... Drive shaft, 18... Drive motor (rotary drive device), 19... Truing car, 20... Dressing car, 24...・・・
...Dressing liquid supply device, 50...Forward feed applying device, 60...Reverse feed applying device, D
S... Dressing liquid, G... Abrasive grains for dressing.

Claims (1)

[Claims] 1. In a device that shapes a grinding wheel using a hard material such as cubic boron nitride as abrasive grains while rotating at high speed, the grinding wheel moves relative to the grinding wheel in parallel and perpendicular directions to the grinding surface. a freely rotatable support base; a truing wheel rotatably supported on the support base facing the grinding surface of the grinding wheel and having a diamond abrasive layer fixed to the outer circumference of the base ring; and a truing wheel coaxial with the truing wheel on the support base. a dressing wheel rotatably supported on the truing wheel; a rotary drive device for rotating the truing wheel to reduce a relative circumferential speed with respect to the grinding wheel; a forward feeding device for relatively advancing the support base; and a forward feed applying device for moving the support base to the grinding wheel grinding surface in order to align the dressing wheel with the grinding wheel after truing the grinding wheel grinding surface with a truing wheel based on the feeding. A grinding wheel shaping device comprising: a traverse device that relatively moves the grinding wheel in a direction parallel to the grinding wheel; and a device that supplies abrasive particles for dressing between the grinding wheel and a dressing wheel aligned with the grinding wheel.