KR20170055140A - Low vibration hand grinder - Google Patents

Abstract

The present invention relates to a low-vibration hand grinder capable of effectively absorbing vibrations generated by a grinding operation and capable of performing a stable grinding operation and reducing the fatigue of an operator due to vibration, and more particularly, And a polishing pad 200 that is rotated by a rotational force transmitted from the driving unit 100 and polishes the polishing surface. A hand grinder, comprising: a suction means (400) installed at a periphery of the main body (300) for absorbing and reducing vibrations generated during grinding by the action of hydraulic pressure; The present invention relates to a low-vibration hand grinder.

Description

[0001] LOW VIBRATION HAND GRINDER [0002]

The present invention relates to a low-vibration hand grinder capable of effectively absorbing vibrations generated by a grinding operation, capable of stable grinding work, and capable of reducing an operator's fatigue due to vibration.

Generally, a hand grinder is a device that performs various types of machining operations by connecting a polishing pad of various sizes to a rotating body (for example, a rotor) that rotates by supplying high-pressure air or electricity, and by using a high rotational force and a frictional force.

Examples of the use of such a hand grinder include not only the surface finishing of welding parts in shipbuilding and heavy industry, the finishing of metal casting, the surface processing of aluminum die casting, but also the removal of inclined metal surface or protrusion, It is also used for finishing finishing work such as contour molding, calibration and fusion.

The hand grinder for this purpose is ergonomically designed for precise work so that the worker should not be fatigued even when used for a long time and the tool must be light in weight so that the worker can work on the hand for finer work. .

In addition, in order to increase the precision of the machined part, the rotating part must be rigid enough to prevent vibration and be made to have high rotation accuracy.

1 shows a conventional general hand grinder.

The conventional hand grinder includes a driving unit 10 that generates a rotational force by a power source, a polishing pad 20 that polishes the polishing surface by rotating the rotational force of the driving unit 10 and rotates the polishing pad 20, And a main body 30 made of a metal.

An air supply unit 11 for supplying compressed air may be formed as a power source for generating rotation of the driving unit 10 at the rear of the main body 30. [ The rotor 12 of the driving unit 10 is rotated by the compressed air supplied through the air supply unit 11. The rotation of the rotor 12 is transmitted to the power transmission unit 13 ) To the polishing pad 20. At this time, the power transmission portion 13 is configured to be connected to the rotation shaft 21 of the polishing pad 20 by changing the direction of the rotation axis of the rotor 12 to a direction perpendicular to the paper surface by a combination of a plurality of bevel gears.

In the conventional hand grinder having the above-described configuration, the driving unit 10 provided with the rotor 12 for generating the rotational force is formed in a full circle, the air supply unit 11 is formed on one side of the driving unit 10, A discharge hole (not shown) is formed. Therefore, a predetermined air pressure is generated in the air supply line, and the rotor 12 is pushed toward the air supply hole by the air pressure to cause eccentricity.

When the eccentricity of the rotor 12 is generated, it causes vibration while rotating, and the vibration is transmitted to the hand grinder, which makes it impossible to perform a stable operation during the grinding operation, and the precision workability is accordingly lowered, There are disadvantages.

Further, the eccentricity of the rotor 12 causes the beating of the bevel gears as the power transmitting portion 13 to be inaccurate, and the rotational force on the rotating shaft can not be accurately transmitted, resulting in a decrease in the rotational force of the polishing pad 20 The efficiency of the grinding operation of the grinding surface is lowered.

In order to solve such a problem, conventionally, a worker wears specially manufactured gloves to prevent the vibration of the equipment itself from being transmitted, or to change the gear type of the power transmitting portion 13 that transmits rotation to the polishing pad 20, Is used.

However, in such a conventional method, when the working method or the environment of the grinder is slightly changed, the friction size between the polishing pad 20 and the polishing surface to be processed is changed, and the vibration of the grinder becomes larger than expected. Therefore, there is a great limitation in the vibration suppression function, and finally, the vibration of the grinder is transmitted to the worker as it is, shortening the workable time and causing wrist disease and the like.

Korean Registered Utility Model No. 20-0412747 (Published on Mar. 23, 2006) Korean Patent Registration No. 10-1363314 (Publication date: 2014. 02. 10)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems of the prior art, and it is an object of the present invention to effectively absorb vibrations generated during a grinding operation and a grinding operation through an electro- And to provide a low-vibration hand grinder that enables more active and efficient operation through control.

According to an aspect of the present invention for achieving the above object, there is provided a method of manufacturing a semiconductor device, comprising: a driving unit installed inside a main body of an external shape to transmit a rotational force of a rotor rotated by a power source to one side; And a suction unit installed at a periphery of the main body to absorb and reduce vibrations generated during grinding by the action of hydraulic pressure. The hand grinder according to claim 1, / RTI >

The suction unit includes a connecting portion for rotatably connecting the main body and the main body, and a first hydraulic chamber and a piston head spaced apart from each other in the circumferential direction of the connecting portion, the first hydraulic chamber being formed at a periphery of the connecting portion, May be made of an electronic actuator having a second hydraulic chamber.

Four actuators may be provided on the upper, lower, left, and right sides of the main body.

The piston head may be formed with a fluid passage hole for allowing a working fluid of the second hydraulic chamber to pass to the first hydraulic chamber when the piston head is moved toward the actuator by the pressure of the first hydraulic chamber.

The fluid passage hole may be formed with a check valve that prevents fluid from passing from the first hydraulic chamber to the second hydraulic chamber.

A sensor installed on one side of the main body for measuring a direction and a magnitude of vibration generated during grinding and a controller for controlling the operation of the sucking means by receiving a signal measured from the sensor.

The control unit can control the optimum excitation direction, frequency and pressure of the hydraulic pressure of the suction unit according to the transmission signal of the sensor.

The control unit can determine the representative vibration value calculated by grasping the operator and the main operation characteristics, and can control the absorption unit based on the setting information selected by the operator.

The vibration-free hand grinder of the present invention effectively absorbs vibrations generated during grinding work, thereby stably performing the grinding operation by increasing the reaction speed by the operation of the operator, reducing the fatigue to the operator by the vibration of the grinder, There is an effect that can be prevented.

In addition, the low-vibration hand grinder of the present invention allows the operator to perform a grinding operation in a selected mode by setting a representative vibration value calculated in advance by grasping a worker and major work characteristics, It has the effect of enabling a more efficient grinding operation under various working conditions.

1 is a side sectional view of a conventional hand grinder,
FIG. 2 is a side sectional view showing a hand grinder according to an embodiment of the present invention,
3 is a cross-sectional view showing a cross section taken along line AA in FIG. 2,
Fig. 4 is a cross-sectional view showing a shape of a depressed portion of the depressurizing means shown in Fig. 3;

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a low-vibration hand grinder according to the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 shows a side cross-sectional view of a grinder in accordance with an embodiment of the present invention.

The grinder according to the present invention includes a driving unit 100 installed inside a main body 300 forming an outer shape to transmit the rotational force of a rotor 120 rotated by a power source to one side, And a suction unit 400 installed at the periphery of the driving unit 100 for absorbing and reducing vibrations generated during the polishing operation by the action of hydraulic pressure .

The main body 300 extends in the longitudinal direction and has a driving unit 100 installed therein. The rear portion of the main body 300 is provided with an air supply portion 110 for supplying compressed air to generate rotation of the driving portion 100. The front portion of the main body 300 is rotated by the driving portion 100, The power transmission unit 130 is provided. The main body 300 forms an external main shape of the grinder, and allows the operator to manually grasp the force to directly control the force that the polishing pad 200 presses the polishing surface.

The driving unit 100 rotates the rotor 120 by the compressed air supplied through the air supply unit 110 and transmits the rotation to the polishing pad 200. The power transmission unit 130 provided at one end of the driving unit 100 converts the direction of the rotation axis of the rotor 120 into a direction perpendicular to the polishing surface and transfers the same to the polishing pad 200, And the rotation torque is transmitted to the motor.

For reference, in the description of the present invention, a configuration using compressed air is used as a power source for generating the rotation of the driving unit 100, but the present invention is not limited thereto, and various power sources such as electricity may be applied.

The polishing pad 200 may be formed in a circular shape horizontally arranged on the polishing surface, and this circular shape is merely an example, and any known construction capable of achieving the role of machining by friction action on the polishing surface by rotation Can be applied.

The suction unit 400 is provided at the periphery of the main body 300 to absorb vibrations generated during the grinding operation of the grinder by the action of hydraulic pressure, thereby reducing the vibration. Specifically, as shown in FIG. 2, the suction unit 400 is installed in a plurality of spaces so as to surround the outer circumferential side of the main body 300 in a circumferential direction so as to be spaced apart from each other by a predetermined distance. A grip portion for gripping by a worker is formed on an outer peripheral portion of the suction means 400 that surrounds the outside of the main body 300. The suction means 400 absorbs the vibration transmitted from the inside of the grinder, And is not configured to be transmitted.

FIG. 3 shows a cross-sectional shape of a connecting portion A-A in FIG. 2, and the structure of the above-described sucking means 400 will be described in more detail.

The suction unit 400 includes a connection part 410 for directly connecting the outside of the main body 300 to which vibration is transmitted from the driving part 100 which is a source of the vibration of the grinder, And a plurality of electromagnetic actuators 420 for absorbing the electromagnetic force.

The connection unit 410 is coupled to the main body 300 in such a manner that the main body 300 rotatably supports the main body 300 by inserting the main body 300 in a predetermined lengthwise direction.

A plurality of actuators 420 are provided in the circumferential direction of the connection portion 410. A chamber in which the hydraulic fluid is filled is formed in the central portion of the suction unit 400 where the connection unit 410 is located and the chamber 420 is provided in the actuator 420. The space between the connection unit 410 and the actuator 420 The first hydraulic chamber C1 is formed in the space and the second hydraulic chamber C2 is formed in the actuator 420, respectively. The first hydraulic chamber C1 and the second hydraulic chamber C2 are formed on the inlet side of the actuator 420 and are separated from each other by the piston head 424 which receives the hydraulic pressure by the vibration transmitted from the connecting portion 410. [ do.

For example, the actuator 420, which is spaced apart from the connecting portion 410, may be installed at four positions on the upper, lower, left, and right sides of the main body 300, Width direction and vibration generated in the vertical and horizontal directions with respect to the polishing surface, respectively.

 The piston head 424 is formed with a fluid passage hole 426 through which the working fluid of the second hydraulic chamber C2 can be passed through the first hydraulic chamber C1. Therefore, when the hydraulic pressure of the first hydraulic chamber C1 is applied to the piston head 424, the working fluid of the second hydraulic chamber C2 is moved to the first hydraulic chamber through the fluid passing hole 426, (424) moves toward the actuator (420) side, thereby absorbing the vibration of the main body (300) transmitted by the vibration of the grinder.

The fluid passage hole 426 is provided to prevent the working fluid of the first hydraulic chamber C1 from moving to the second hydraulic chamber C2 when the pressure of the fluid is received from the first hydraulic chamber C1. Preventing plate film 436 is formed. For example, the backflow prevention valve 436 may be configured to restrict the movement of fluid in one direction by coupling a flexible material such as a rubber material to the fluid passage hole 426 by a hinge. In addition, Various known configurations capable of restricting the operation of the apparatus can be applied.

3, reference numeral 424 denotes a piston 424 extending from the piston head to one side and inserted into the actuator.

According to an embodiment of the present invention, a sensor 500 installed on one side of the main body 300 of the grinder and measuring the direction of the vibration generated in the polishing operation, and a signal measured from the sensor 500 And a control unit (not shown) for controlling the operation of the sucking means 400 when it is received.

The control unit is configured to control the optimum excitation direction, frequency, and hydraulic pressure of the absorber 400 according to the transmission signal of the sensor 500 installed at one side of the main body 300.

The grinder of the present embodiment configured as described above includes a sensor 500 for measuring vibration and a control unit for controlling the sucking means in accordance with the measurement signal of the sensor 500, By setting the representative vibration value in advance, various grinders can be efficiently operated by the operator's choice.

Table 1 below shows the magnitude and direction of vibration according to the type of grinder.

Table 1. Vibration size and direction of grinder

As shown in Table 1, most grinders exhibit the largest vibration amplitude between 205 Hz and 800 Hz, and the vibration decreases below 125 Hz. Such vibration magnitude and direction can be changed in direction and size depending on the surface strength and roughness of the polishing surface to be worked.

The grinder according to the present invention can preset the vibration information for each kind of grinder in advance and perform the optimum vibration control by the control unit.

As an example of the grinder operation for such a function, the control unit may be set to the representative vibration value calculated by grasping the operator who operates the grinder and the main operation characteristics. At this time, the simple operation of the grinder can be performed for a predetermined time to set the representative vibration value, and the vibration characteristic according to the magnitude of the force applied by the operator according to the surface type to be polished can be set. This information and the representative vibration value are respectively stored as the setting information of the suction unit 400 of the control unit. When the operator performs the grinder operation, the operator can select a desired item from among the setting information and execute the operation.

As described above, the grinder according to the embodiment of the present invention is provided with the suction unit 400, and the functions of the sensor 500 and the control unit are added to control the vibration in three directions through the independent vibration control in both vertical and horizontal directions And it is possible to accelerate the reaction speed of the operation of the grinder operator.

In addition, it is possible to efficiently control the vibration of the suction unit 400 by setting the control unit through the worker and the main operation characteristics, and enables a more active and efficient operation through the operator-oriented setting.

Therefore, since the grinder is stably operated without rocking, the grinding operation does not generate vibration, so that stable operation can be performed. In addition to this, it is possible to perform precision machining and thereby reduce the fatigue of the operator due to vibration. Solution.

Although the low-vibration hand grinder according to the present invention has been described with reference to the embodiments shown in the drawings, it is to be understood that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. Accordingly, the scope of the true technical protection should be determined by the technical idea of the appended claims.

100:
120: Rotor
200: polishing pad
300:
400: Suction means
410:
420: Actuator
424: Piston head
436: Backflow prevention valve
500: Sensor

Claims (8)

A driving unit 100 installed inside the main body 300 forming an external shape and transmitting rotational force of a rotor rotated by a power source to one side; And a polishing pad (200) rotating by a rotational force transmitted from the driving part (100) to polish a polishing surface; A hand grinder comprising:
A suction unit 400 installed at the periphery of the main body 300 for absorbing and reducing vibration generated during grinding by the action of hydraulic pressure; Wherein the grinding wheel is a grinding wheel. The method according to claim 1,
The sucking means (400)
A connecting part 410 for rotatably connecting the main body 300 by inserting the main body 300 in an axial direction; And
The first hydraulic chamber C1 formed at the periphery of the connection portion 410 and the second hydraulic chamber C2 defined by the piston head 424 are spaced apart from each other in the circumferential direction of the connection portion 410, An electromagnetic actuator 420 having an electromagnetic actuator 420; Wherein said grinding wheel is a grinding wheel. 3. The method of claim 2,
Wherein four actuators (420) are provided on the upper, lower, left, and right sides of the main body (300). 3. The method of claim 2,
When the piston head 424 is moved toward the actuator 420 by the pressure of the first hydraulic chamber C1, the working fluid of the second hydraulic chamber C2 is transferred to the first hydraulic chamber C1 And a fluid passage hole (426) through which the fluid is passed. 5. The method of claim 4,
Wherein the fluid passage hole (426) is formed with a check valve plate (436) for preventing fluid from passing from the first hydraulic chamber (C1) to the second hydraulic chamber (C2) . The method according to claim 1,
A sensor 500 installed at one side of the main body 300 to measure a direction and a magnitude of vibration generated during a grinding operation; And
A controller receiving the signal measured by the sensor 500 and controlling the operation of the sucking unit 400; Further comprising a second grinding wheel for grinding the grinding wheel. The method according to claim 6,
Wherein the control unit controls the optimum excitation direction, frequency and pressure of the hydraulic pressure of the suction unit (400) according to a transmission signal of the sensor (500). The method according to claim 1,
Wherein the control unit controls the suction unit (400) by setting information representative of a worker and a main operation characteristic and calculating a representative vibration value in advance.

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