JPH0929602A - Polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent Generation of abnormal noise as well as oscillation of a device resulting from the eccentric rotation of its polishing mechanism. SOLUTION: On a rotation drive shaft 30 a polishing mechanism 39 is mounted which is provided with a polishing pad 42 on an eccentric shaft 40 rotating integrally with the shaft 30 while thereon a balancer 81 is mounted whose position of the center of gravity is set eccentrically on the opposite side to the eccentric direction of the pad 42 with respect to the axis of the shaft 30. When the shaft 30 is rotated the mechanism 39 and the balancer 81 is eccentrically rotated in an integrated manner to thereby cancel the centrifugal force by the eccentric rotation of the two 39, 81. No lateral dislocation of the shaft 30 caused by the eccentric rotation of the mechanism 39 is therefore generated and no abnormal noise or oscillation of a device caused thereby is also generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus that performs polishing while eccentrically rotating a polishing pad.

[0002]

2. Description of the Related Art When a work conveyed in one direction is polished by a sanding belt that travels in the same direction as the conveying direction, the sanding belt polishing direction with respect to the work is constant. On the surface, many streaky scratches that are minute but parallel to each other remain.
Therefore, in order to eliminate such scratches, the surface of the work is finished by polishing such that the polishing direction of the work is not constant.

As a polishing device used for such finishing, a rotary drive shaft rotated by a motor is provided above a conveyor for horizontally transporting a work, and
There is one in which a polishing mechanism having a structure in which a polishing pad is attached to an eccentric shaft that rotates integrally with the rotary drive shaft is provided. When the rotary drive shaft is rotationally driven, the polishing pad is eccentrically rotated about the rotary drive shaft, and the work is finish-polished by the eccentrically rotating polishing pad. In such a polishing apparatus, the polishing pad is rotated at a high speed in order to improve the smoothness of the finish.

[0004]

In such a polishing apparatus, due to the eccentric rotation of the polishing mechanism, a centrifugal force proportional to the square of the rotation speed acts on the rotary drive shaft. Since the rotation speed is set to a high speed, the centrifugal force becomes considerably large. Then, due to the large centrifugal force, the shaft center of the rotary drive shaft is deviated, which causes a problem that the device vibrates or an abnormal noise occurs.

The present invention was devised in view of the above circumstances, and it is an object of the present invention to prevent vibration and abnormal noise of the apparatus due to eccentric rotation of the polishing mechanism.

[0006]

SUMMARY OF THE INVENTION The present invention comprises a conveyer for conveying a work, and a polishing mechanism in which a polishing pad is attached to an eccentric shaft that rotates integrally with a rotary drive shaft. In the case of polishing by the eccentric rotation of the pad, the rotary drive shaft is integrally rotatable with a balancer having a center of gravity at a position opposite to the center of gravity of the polishing mechanism with respect to the shaft center. It is characterized by

In this invention, since the centrifugal force due to the eccentric rotation of the polishing mechanism and the centrifugal force due to the eccentric rotation of the balancer are balanced, the axial center of the rotary drive shaft can be prevented from deviating.

According to a second aspect of the present invention, in the first aspect of the invention, the eccentricity between the weight of the balancer and the center of gravity is the eccentricity between the weight and the center of gravity of the polishing mechanism, and the moment value obtained by multiplying the weight and the eccentricity is It is characterized in that it is set so as to be substantially equal to the value of the moment multiplied by the quantity. In the invention having such a configuration, the centrifugal force is also substantially equalized by substantially equalizing the moments of the polishing mechanism and the balancer.

[0009] The invention of claim 3 is claim 1 or claim 2.
The invention is characterized in that the rotation drive shaft is supported by a movable base provided so as to be capable of reciprocating in a direction traversing a work transfer path. In the invention of such a configuration, the polishing pad contacts the work while drawing a complicated trajectory combining reciprocating movement and eccentric rotation.

[0010]

According to the first aspect of the present invention, it is possible to prevent vibration and abnormal noise of the apparatus due to the shake of the rotary drive shaft due to the eccentric rotation of the polishing mechanism.

According to the second aspect of the present invention, the weight and eccentricity of the balancer can be set under optimum conditions, so that the effect of preventing the rotation of the rotary drive shaft is high.

According to the third aspect of the invention, since the polishing pad polishes while performing complicated movements, the polishing effect is high.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. On the upper surface of the base 1, there is provided a conveyor 2 in which an endless conveyor belt 4 is spanned between a pair of rolls 3 which are horizontally spaced from each other.
Are conveyed from right to left in FIG.

The base 1 is provided with four elevating legs 5 protruding from the upper surface thereof, and the four elevating legs 5 are integrally driven up and down by rotating the elevating handle 6. These four
The elevating legs 5 of the book support an elevating frame 7 located above the conveyor 2 from below. The elevating frame 7 is composed of an elevating base 8 having a horizontal plate shape and a housing 9 surrounding the elevating base 8. An operation panel 10 is provided on the front surface of the housing 9.

On the upper surface of the elevating base 8, four guide rails 11 are fixed in a direction orthogonal to the direction in which the work W is conveyed by the conveyor 2. These guide rails 11
A horizontal plate-shaped movable base 12 is movably guided by a slider 13 fixed to the lower surface thereof.

A bracket 14 attached to the left side edge of the movable base 12 in FIG. 2 is attached with a driven connector 15 rotatable about a vertical axis. on the other hand,
The elevating base 8 is provided with a drive pulley 17 that is rotated around a vertical axis by a sliding motor 16 and a driven pulley 18 that is rotatable around a vertical axis like the drive pulley 17. A timing belt 19 is stretched between 18 and. Further, an eccentric shaft 20 is integrally rotatably attached to the driven pulley 18, and a drive connector 21 is rotatably attached to the eccentric shaft 20. And this drive connector 2
1 and the driven connector 15 are connected by a link bar 22 formed of a screw rod. With this configuration, when the sliding motor 16 is driven, the eccentric rotational motion of the drive connector 21 is converted into the linear motion of the driven connector 15 and transmitted, so that the movable base 12 moves along the guide rail 11 in the conveyance direction of the work W. It is designed to reciprocate in the orthogonal directions.

The movable base 12 is provided with a drive mechanism for polishing the work W. Less than,
This drive mechanism will be described. A mounting base 23 is fixed to the lower surface of the movable base 12,
2 and the mounting base 23 are provided with mounting holes 12A and 23A, which are aligned with each other between the bases 12 and 23, at two positions spaced from each other in the direction orthogonal to the conveyance direction of the work W. A shaft case 24 is attached to each of the two mounting holes 12A and 23A.
As shown in FIG. 4, the shaft case 24 includes a bell-shaped upper case 24U and a plate-shaped lower case 24L that closes an opening on the lower surface of the upper case 24U. The bolt 26 passed through is screwed into the screw hole 27 of the upper case 24U to be integrally assembled. A bolt 29, which has been passed through the through hole 28 of the mounting base 23 from above, is screwed into the screw hole 27 before being mounted on the movable base 12, whereby the shaft case 24 is mounted via the mounting base 23. It is integrally attached to the movable base 12. Shaft case 2 attached in this way
Reference numeral 4 vertically penetrates the movable base 12.

Each shaft case 24 rotatably supports a rotary drive shaft 30 with its axis oriented in the vertical direction. The rotary drive shaft 30 penetrates the bearing hole 31 of the lower case 24L from below, and the upper end of the rotary drive shaft 30 penetrates the bearing hole 32 of the upper case 24U. In each of the upper and lower bearing holes 31 and 32, a rotary drive shaft 30 is supported by a thrust ball bearing 33 and a radial ball bearing 34 so as to rotate smoothly.

Both bearings 33 and 34 in the bearing hole 32 of the upper case 24U are supported from below by a bearing receiving portion 35. Further, a bearing nut 37 is attached to the male screw portion 36 formed on the upper end of the rotary drive shaft 30.
Is engaged with the inner race 34A of the radial ball bearing 34 via the bearing washer 38 from above, whereby the rotary drive shaft 30 moves downward with respect to the shaft case 24. Is supported by the infallible. On the other hand, in the bearing hole 31 of the lower case 24L, both bearings 33,
34 is supported from below by a collar portion 41 of an eccentric shaft 40 formed at the lower end of the rotary drive shaft 30, and this prevents both bearings 33, 34 from falling off.

The eccentric shaft 40 is formed at the lower end of the rotary drive shaft 30 as described above. The eccentric shaft 40 has a circular cross section, and its center position Ps is the rotational drive shaft 30.
The center of rotation P is eccentric by a slight dimension such as several millimeters. The amount of eccentricity is set so that both eccentric shafts 40, 40 have the same size. The eccentric shaft 40 projects downward from the above-mentioned collar portion 41, and a polishing pad 42 is attached to the projected eccentric shaft 40. The eccentric shaft 40 and the polishing pad 42 constitute the polishing mechanism 39 of the present invention.

The mounting structure of the polishing mechanism 39 is as follows. Before the rotary drive shaft 30 is attached to the shaft case 24, two radial ball bearings 43, 43 are vertically fitted from the bottom to the eccentric shaft 40, and the male screw portion 44 at the lower end of the eccentric shaft 40 is fitted in advance. The bearing nut 45 is screwed, and the bearing nut 45 is engaged with the inner race 43A of the lower radial ball bearing 43 from below through the bearing washer 46.
As a result, both bearings 43, 43 are attached to the eccentric shaft 40 so as not to fall off.

Further, a through hole 48 of a holder plate 47 is fitted in the flange portion 41 from above so as to be relatively rotatable, and the holder plate 47 is attached to the upper radial ball bearing 4.
The outer race 43B of No. 3 is engaged. Then, the two holder plates 4 that are separately fitted to the eccentric shafts 40, respectively.
One common pad holder 49 is fixed to the units 7 and 47 by bolts (not shown). At this time,
The eccentric directions of the eccentric shafts 40, 40 with respect to the rotary drive shaft 30 are set to be the same as each other.

The pad holder 49 is a work W as a whole.
It has a long shape in the direction transverse to the conveyance direction of. Two accommodating holes 51, 51 that open upward are formed in the pad holder 49, and the eccentric shaft 40 and the radial ball bearings 43, 43 are accommodated in these accommodating holes 51. The pad holder 49 includes the eccentric shafts 40,
When the eccentric 40 rotates, the workpiece W moves in a circular locus while always maintaining a constant posture in the transport direction of the workpiece W.

A mounting groove 52 is formed on the lower surface of the pad holder 49 and opens over the entire length thereof. A locking step 53 is formed in the mounting groove 52 by recessing the upper portions of both inner wall surfaces. Such mounting groove 52
A polishing pad 42 is attached to the.

The polishing pad 42 has a horizontal plate-shaped pad body 42A and a polishing sheet 5 such as felt on the lower surface thereof.
4 is attached, and this polishing sheet comes into contact with the surface of the work W. A mounting portion 42B is integrally formed so as to extend along the length direction from the upper surface of the pad body 42A. The mounting portion 42B has the mounting portion 4B.
A plate-shaped pad flange 55 wider than 2B is fixed by bolts 56. Such polishing pad 42
Fits the mounting portion 42B into the mounting groove 52 of the pad holder 49 and mounts the pad flange 55 in the mounting groove 5
It is supported by the pad holder 49 by engaging with the two locking step portions 53.

Further, one end (on the right side in FIG. 3) of the pad flange 55 is locked by engaging the inclined surfaces with the pad stopper 57 fixed to the pad holder 49. On the other hand, the end of the pad flange 55 on the opposite side to the above projects laterally from the pad holder 49, and this projecting portion is held by a clamp 58 provided on the pad holder 49. This clamp 58
When the lever 58A is operated to pull up the shaft 58B, the pad flange 55 is lifted to a predetermined height by the engagement of the nut 58C screwed on the lower end of the shaft 58B, and the pad flange 55 is lifted by the compression coil spring 58D. Is regulated, so that the pad flange 55 is fixed to the pad holder 49. Lever 58A
When the shaft 58B is lowered by operating in the direction opposite to the above, the pad flange 55 is lowered and the pressing by the compression coil spring 58D is released, whereby the pad flange 55 can be removed from the pad holder 49.

As described above, the polishing pad 42 is attached to the two eccentric shafts 40, 40 via the pad holder 49. The polishing pad 42 includes the eccentric shafts 40,
By rotating 40 at the same speed, they are rotationally driven so as to draw a locus of a circle having a radius of an eccentric dimension while maintaining a constant posture with respect to the conveyor 2. The lifting base 8 has a polishing pad opening 59 for allowing the polishing pad 42 to move.

Next, a mechanism for rotationally driving both eccentric shafts 40, 40 will be described with reference to FIGS. 2 and 3. Both shaft cases 2 of the movable base 12 in FIG.
A slide base 60 is attached by bolts 61 at positions above 4, 24. The bolt 61 penetrates the long hole 62 of the slide base 60 to move the movable base 1.
Since the slide base 60 is screwed into the movable base 12, the mounting position of the slide base 60 with respect to the movable base 12 can be arbitrarily adjusted within a certain range in the vertical direction in FIG. A polishing motor 63 is fixed to the slide base 60 so as to project downward.
A vertical output shaft 64 of the polishing motor 63 projects upward from the slide base 60, and a drive pulley 65 that rotates integrally with the output shaft 64 is attached to the output shaft 64.

A slide base 66 is attached by a bolt 67 to a position to the right of the intermediate position between the shaft cases 24, 24 of the movable base 12 in FIG. Since the bolt 67 penetrates the elongated hole 68 of the slide base 66 and is screwed into the movable base 12, the mounting position of the slide base 66 to the movable base 12 is as shown in FIG.
Can be arbitrarily adjusted within a certain range in the left-right direction. A driven pulley 69 having the same height as the drive pulley 65 is attached to the slide base 66, and a timing belt 70 is stretched between the driven pulley 69 and the drive pulley 65. As a result, when the polishing motor 63 is driven, the driven pulley 69 is rotated at high speed.
The timing belt 70 can be kept in a tension state by adjusting the position of the slide base 60 that supports the polishing motor 63.

Further, the driven pulley 69 is provided with a drive pulley 71 which rotates integrally with the driven pulley 69. And, at the upper ends of the two rotary drive shafts 30, 30, respectively,
Driven pulleys 72, 72 that rotate integrally with these are attached. The drive pulley 71 and the driven pulleys 72, 7
A timing belt 73 is stretched between the two in a triangular shape. As a result, when the polishing motor 63 is driven, the two rotary drive shafts 30, 30 rotate at the same speed and high speed, and at the same time, the two eccentric shafts 40, 40 rotate at the same speed and high speed. The timing belt 73
Can be kept in tension by adjusting the position of the slide base 66 that supports the driven pulley 69 and the drive pulley 71.

In the polishing apparatus of this embodiment having the above structure, the elevating frame 7 is adjusted according to the thickness of the work W.
Is set up so that the polishing pad 42 comes into contact with the work W with an appropriate pressing force, and the slide motor 16 and the polishing motor 63 are driven in this state, and the work W is transported. Then, the workpiece W to be transported
The polishing pad 42 polishes the surface of the
A number of streaky scratches on the surface of the skin disappear.

Polishing pad 4 for work W at this time
The movement of 2 is the linear movement of the work W by the conveyor 2,
A reciprocal linear movement of the movable base 12 in a direction orthogonal to the movement direction of the work W and a rotational movement of the polishing pad 42 that eccentrically rotates with respect to the movable base 12 form a complex trajectory. Therefore, the polishing pad 42
The polishing direction for the workpiece W always changes to an unspecified direction, and the surface finish of the workpiece W becomes good.

In the above polishing apparatus, since the polishing pad 42 is eccentrically rotated at a high speed, a large centrifugal force acts on the rotary drive shaft 30, but in the present embodiment, the centrifugal force of the polishing pad 42 causes it. Means for preventing the shaft center P of the rotary drive shaft 30 from moving are provided. Hereinafter, the configuration will be described.

The inside of the shaft case 24 supporting the rotary drive shaft 30 is a storage space 80 having a circular cross section that is concentric with the rotary drive shaft 30. In the housing space 80, a balancer 81 made of the same material as the rotary drive shaft 30 and having a columnar shape as a whole is housed. The balancer 81 is provided with a circular fitting hole 82 centered at a position displaced from the center Gb by a predetermined distance and having the same diameter as the rotary drive shaft 30. The balancer 81 has the fitting hole 82. It is attached to the rotary drive shaft 30 by fitting 82.

The mounting structure of the balancer 81 is as follows. A key groove 83 parallel to the axis of the rotary drive shaft 30 is formed on the outer circumference of the rotary drive shaft 30, and a key groove 84 is formed on the inner circumference of the fitting hole 82 of the balancer 81. By fitting 85, the rotary drive shaft 30 and the balancer 81 are integrally rotatably connected. Further, the balancer 81 is formed with a female screw hole 86 that reaches the fitting hole 82 from its outer circumference. A bolt 87 is screwed into the female screw hole 86 to press the tip of the bolt 87 against the key 85. As a result, the balancer 81 is fixed to the rotary drive shaft 30. When the rotary drive shaft 30 rotates, the balancer 81 rotates eccentrically together with the rotary drive shaft 30 in the accommodation space 80.

Next, the weight and arrangement of the balancer 81 will be described with reference to FIG. The balancer 81 is the polishing pad 4
Since it is for canceling the centrifugal force generated by the eccentric rotation of 2, the polishing pad 42 is used in terms of weight and arrangement.
It is set based on the weight of the polishing mechanism 39 including the eccentric shaft 40 and the amount of eccentricity of the center of gravity Gs from the axis P of the rotary drive shaft 30. Since the polishing mechanism 39 has a symmetrical structure with respect to the eccentric shaft 40, the polishing mechanism 3
The position of the center of gravity Gs of 9 is the axis Ps of both eccentric shafts 40, 40,
It is on a straight line connecting Ps, and its position is both axis centers Ps and Ps.
It is almost in the middle position.

As a method for setting the position of the center of gravity and the weight of the balancer 81, in the present embodiment, first, the center of gravity G of the balancer 81 is set.
b is located on the side opposite to the position of the center of gravity Gs of the polishing mechanism 39 with respect to the line Q passing through the axis P of the rotary drive shaft 30. Furthermore, the value of the moment obtained by multiplying the eccentric amount of the center of gravity position Gs of the polishing mechanism 39 and the weight is substantially the same as the value of the moment obtained by multiplying the eccentric amount of the center of gravity position Gb of the balancer 81 and the weight. Therefore, the eccentricity amount and the weight of the center of gravity position Gs of the balancer 81 are set based on this.

The relational expression of the moment between the polishing mechanism 39 side and the balancer 81 side will be described later. The weight including all of the polishing mechanism 39 that is eccentrically rotated with respect to the rotation drive shaft 30 is Ws, and the eccentric amount from the axis P of the rotation drive shaft 30 at the center of gravity position Gs is Es. On the other hand, the weight of the balancer 81 is Wb, and the eccentric amount at the center of gravity position Gb is Eb (see FIG. 5). However, in the present embodiment, since the balancer 81 is made of the same material as the rotary drive shaft 30 as described above, that is, has the same specific gravity, the moment on the balancer 81 side includes the rotary drive shaft 30 existing in the fitting hole 82. Calculated as having an elliptic shape. The key 85 and the bolt 87 are included in the balancer 81 as the same material as the rotary drive shaft 30 and the balancer 81. Further, the space in the key groove 83 and the space in the female screw hole 86 are not considered in the calculation because their volumes are so small that they can be ignored.

Under the above conditions, the moment Ms on the polishing mechanism 39 side and the moment Mb on the balancer 81 are Ms = Ws × Es (1) Mb = Wb × Eb.・ ・ (2) Here, the polishing mechanism 39 has two balancers 81,
Since it is shared by 81, the relational expression of both moments is Mb = Ms / 2 ... (3). Further, the area S of the upper and lower end surfaces of the balancer 81 is
If the height is h and the specific gravity of the material is d, the balancer 81
The weight Wb of Wb = S × h × d (4) Therefore, from the above equations (2), (3), and (4), S × h × Eb = Ms / 2d (5) In this equation (5), the value Ms / 2d of the right term is predetermined, so the area S and height h of the balancer 81 are
And the eccentric amount Eb of the center of gravity position can be arbitrarily set based on the equation (5).

The two balancers 81, 81 provided with the eccentric amount Eb and the weight Wb at the center of gravity as described above are eccentrically rotated together with the polishing mechanism 39. Due to the eccentric rotation of the balancer 81, a centrifugal force having substantially the same magnitude as the centrifugal force generated by the eccentric rotation of the polishing mechanism 39 is generated in the opposite direction with respect to the axis P of the rotary drive shaft 30. As a result, both centrifugal forces are canceled out, and a force that causes lateral shake on the rotary drive shaft 30 is prevented from acting. Therefore, there is no possibility that the vibration or the abnormal noise of the device that occurs when the balancer 81 is not provided is generated in this embodiment.

In the above embodiment, since the specific gravity of the balancer 81 is the same as that of the rotary drive shaft 30, it is assumed that the balancer 81 forms a cylindrical body including the rotary drive shaft 30 when calculating the moment. As a result, the balancer 8
The center Gb of the circle 1 becomes the center of gravity position as it is, and the labor of subtracting the portion of the rotary drive shaft 30 in the calculation of the weight is omitted, and as a result, the eccentric amount Eb and the weight Wb of the center of gravity position Gb are calculated. The formula for setting is simplified.

When the balancer 81 is made of a material having a specific gravity different from that of the rotary drive shaft 30, the rotary drive shaft 30 is used.
The calculation becomes a little complicated because it is necessary to calculate the center of gravity position and weight of only the balancer 81 excluding the part of. However, the moment value obtained by multiplying the eccentric amount of the center of gravity position of only the balancer 81 by the weight is It is the same as the present embodiment in that it is set to be the same as the value of the moment of the polishing mechanism 39.

<Other Embodiments> The present invention is not limited to the embodiments described above and illustrated in the drawings. For example, the following embodiments are also included in the technical scope of the present invention. In addition to the above, various modifications can be made without departing from the scope of the invention.

(1) In the above embodiment, the case where the polishing mechanism 39 moves in parallel without changing its posture has been described.
The present invention can also be applied to the case where the polishing mechanism 39 rotates about the eccentric shaft 40.

(2) In the above embodiment, the case where the movable base 12 that reciprocates so as to traverse the conveyance path of the work W is provided has been described, but according to the present invention, such a movable base 12 is not provided. Alternatively, the rotary drive shaft may be supported at a fixed position with respect to the conveyor.

(3) In the above embodiment, the balancer 81 has a cylindrical shape as a whole, but according to the present invention, the balancer may have a shape other than the cylindrical shape. .

(4) In the above embodiment, the polishing pad 42
Has been described as being supported by two rotary drive shafts 30, 30, the present invention is not limited to the case where the polishing pad is supported by one rotary drive shaft or is supported by three or more rotary drive shafts. It can be applied even if it is.

[Brief description of drawings]

FIG. 1 is an overall external front view of an embodiment of the present invention.

FIG. 2 is a plan view of a polishing mechanism.

FIG. 3 is a right side view of the polishing mechanism.

4 is a sectional view taken along line AA of FIG.

FIG. 5 is a schematic plan view showing the positional relationship between the polishing mechanism and the balancer.

[Explanation of symbols]

 2 ... Conveyor 12 ... Movable base 30 ... Rotational drive shaft 39 ... Polishing mechanism 40 ... Eccentric shaft 42 ... Polishing pad 81 ... Balancer

Claims (3)

[Claims] 1. A conveyor for conveying a work, and a polishing mechanism having a polishing pad attached to an eccentric shaft that rotates integrally with a rotary drive shaft, wherein the polishing pad eccentrically rotates with respect to the conveyed work. The polishing apparatus according to claim 1, wherein the rotary drive shaft is integrally rotatable with a balancer having a center of gravity at a position eccentric to a side opposite to the center of gravity of the polishing mechanism with respect to the axis of the rotary drive shaft. 2. The weight of the balancer and the eccentric amount of the center of gravity are
2. The polishing according to claim 1, wherein the value of the moment obtained by multiplying the weight by the amount of eccentricity is set to be substantially equal to the value of the moment obtained by multiplying the weight of the polishing mechanism by the amount of eccentricity at the center of gravity position. apparatus. 3. The polishing apparatus according to claim 1 or 2, wherein the rotary drive shaft is supported by a movable base provided so as to be capable of reciprocating in a direction traversing a work transfer path.