JP2008119759A - Shot blasting device and shot blasting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for shot blasting capable of deburring a workpiece in sheet shape easy to generate a processing distortion efficiently, uniformly, and inexpensively without resulting in generation of processing distortion even if the workpiece has a relatively large size. <P>SOLUTION: The shot blasting device is equipped with a workpiece retaining unit 2 installed in a casing body 1 for retaining the workpiece W in the vetrtical attitude in such a way that it can make rotation and revolutions in the horizontal direction and an impeller 3 installed on one side of the casing body 1 for casting the shot onto the workpiece W, and it is arranged so that the workpiece W held by the unit 2 makes rotation and revolutions at all times within the blasting area A of the impeller 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  In the present invention, various parts made of light alloy die cast products represented by machine parts and automobile parts, etc., which tend to be thinned in response to demands for weight reduction and production cost reduction in recent years, are treated members (hereinafter referred to as “workpieces”). And a projecting material (hereinafter referred to as “shot”) that is accelerated and projected by a rotary impeller (hereinafter referred to as “impeller”) to a burr formed on the flat plate portion of the workpiece, and collides with the workpiece. The present invention relates to a shot blasting apparatus and a shot blasting method capable of accurately deburring without causing distortion due to blasting.

In various parts made of light alloy die-cast products, burrs are generated in the manufacturing process due to the mating surface of the manufacturing mold or the uneven shape of the parts, and deburring is indispensable.

Conventional shot blasting methods are widely used for deburring and surface machining of workpieces that are blasted by colliding with shots that are accelerated and projected by an impeller. It was developed for large objects such as engine blocks, and the prior art for deburring relatively small workpieces is loaded into a rotating drum and rolled while rolling. Although there is a method of sting, the workpiece is limited to one that can withstand the rolling as described above and has a strength that does not cause processing distortion in the collision of a shot from any direction.

When deburring a thin plate workpiece with a conventional shot blasting device, there is a problem that even if the workpiece can be deburred, distortion occurs due to the collision energy of the shot and the product value is impaired. Deburring was attempted by reducing the projection speed, projection amount, or projection density, but there were problems such as partial deburring being incomplete and processing time required.

As a device and method for solving the above-described problems using a shot blasting device, the present inventors have: a) a fixed-width projection area where a shot is projected by an impeller, and b) horizontal rotation about a revolution axis. A reed is provided around the outer periphery of the rotating reed so that a thin plate-like workpiece can be loaded and unloaded in a vertical state, and is provided radially at a fixed interval around the revolving shaft, and c) a horizontal surface of the revolving reed The processing distortion is reduced by blasting so that the rotation angle of the rotary rod is less than 45 degrees while the thin plate-like workpiece inserted in the vertical state in the mesh cage by the rotation passes through the width of the projection area. Patent Document 1 that facilitates deburring without occurrence has been disclosed.

However, in the invention of Patent Document 1, the deburring located on the impeller side of the workpiece rotated by the rotary rod can be accurately removed without causing distortion of the workpiece, but the deburring located on the revolving shaft side of the rotating rod is not. There is an incomplete point, and when the size of the workpiece increases, the influence tends to increase.
Japanese Patent No. 3827174

  The problem to be solved by the present invention is that shots can be efficiently and uniformly performed at low cost without causing processing distortion even if the size of the thin plate-shaped workpiece that is likely to generate processing distortion is relatively large. A blasting apparatus and a shot blasting method thereof are provided.

  As a result of intensive studies, the present inventors have solved the above problems, and the shot blasting apparatus and the shot blasting method will be described below with reference to FIGS.

  As shown in FIG. 1, the first invention is a work holding unit (2) for holding a plate-like work (W) in a vertical state and rotating and revolving in a horizontal direction, and the work (W). An impeller (3) for projecting a shot is provided, and the workpiece (W) being blasted held by the workpiece holding unit (2) always rotates and revolves within the projection area (A) of the impeller (3). This is a shot blasting apparatus designed to perform the above.

According to a second aspect of the present invention, a station disk (5) that rotates horizontally around the rotation axis A (4) is provided at the approximate center of the casing body (1), and a plate-like workpiece (W) is provided on the station disk (5). ) In a vertical state and the workpiece (W) is rotated and revolved in the horizontal direction, and the workpiece (W) is shot on one side of the casing body (1). The impeller (3) for projecting is provided, and the blasted work (W) held by the work holding unit (2) always rotates and revolves within the projection area (A) of the impeller (3). This is a shot blasting apparatus.

  According to a third aspect of the invention, the work holding unit (2) according to the first or second aspect of the invention comprises a rotating disk (7) that revolves in the horizontal direction about the rotating shaft B (6), and the rotating disk (7 ) A plurality of spindles (8) erected on the spindle (8), and a workpiece holder (8) on which a plate-like workpiece (W) can be loaded and unloaded and held vertically. 9).

According to a fourth aspect of the present invention, there is provided a work holder (9) at a position where the work holder (9) of the third invention revolves and is closest to the impeller (3).
Is a shot blasting device in which the work holder (9) rotates so as to coincide with the surface of the plate-like work (W) held by the impeller (3) and the projection direction center line of the impeller (3).

A fifth invention is a shot blasting device in which one or a plurality of workpiece holders (9) are provided on the support shaft (8) of the third or fourth invention.

According to a sixth aspect of the present invention, the work holder (9) according to any one of the third to fifth aspects of the present invention is a net formed by a wear-resistant wire or a frame formed by a wear-resistant bar. It is a shot blasting device consisting of a body.

The seventh invention is a deburring process formed on a workpiece (W) made of a plate material having a thickness of 2.0 to 0.3 mm, and the plate-like workpiece (W) is in a vertical state in the casing body (1). And a work holding unit (2) provided to rotate and revolve in the horizontal direction, and an impeller (3) for projecting a shot onto the work (W) on one side of the casing body (1). A shot blasting device in which the workpiece (W) being blasted held by the workpiece holding unit (2) always rotates and revolves within the projection area (A) of the impeller (3); The processing conditions are: shot projection speed: 30 to 60 m / sec, projection time: 60 to 180 sec, projection density: 4.5 to 7.5 Kg / m 2 · min, and the amount of distortion generated in the workpiece by processing is 0 Shot blasting to 3mm or less Is the method.

  The shot blasting apparatus and the shot blasting method of the present invention are applied to a thin plate-like workpiece made of a light alloy die-cast product used in machine parts and automobile parts that tend to be thin in response to demands for weight reduction and manufacturing cost reduction. The workpiece with the flat plate portion held perpendicular to the deburring formed is always rotated and revolved in the horizontal direction within the shot projection area to perform blasting (deburring), thereby straining the workpiece. Deburring can be performed accurately without causing it to occur, and mass production and systems can be facilitated.

  Hereinafter, the best embodiment of the present invention will be described with reference to FIGS.

FIG. 1 shows a rotating disk (7) that revolves horizontally around a rotating shaft B (6), and a plurality of support shafts (8) that are erected on the rotating disk (7) so as to be able to rotate. The relationship between the work holding unit (2) and the impeller (3) comprising a work holding tool (9) that allows a plate-like work (W) to be loaded and unloaded on the support shaft (8). The workpiece (W) always rotates and revolves within the projection area (A) of the impeller (3), so that the workpiece (W) is thin and relatively large in size. However, it shows a basic configuration that can be carried out efficiently, uniformly and inexpensively without causing processing distortion.

FIG. 2 shows a station disk (1) which is provided with an impeller (3) on one side and a casing body (1) whose inner side is divided into a blast area (10) and a work entry / exit area (11). 5) A workpiece holding unit (2) having the basic structure shown in FIG. 1 is mounted on the workpiece, and the workpiece (W) of the workpiece holding unit (2) is blasted (deburred) into the workpiece holding unit (2). 1 shows a shot blasting apparatus in which deburring processing according to the present invention can be mass-produced and systematized by enabling simultaneous setting and unloading.

In FIG. 3, two spindles (8) are erected on a rotating disk (7) that revolves in the horizontal direction with the rotation axis B (6) as an axis, so that each spindle (8) can rotate. An embodiment of a work holding unit (2) provided with two work holders (9) and capable of deburring four works (W) at the same time is shown. The support shaft (8) and the work holder (9) that rotate during one rotation are rotated three times in the horizontal direction, and as shown in FIG. At the position where the workpiece holder (9) of 8) is closest to the impeller (3), the surface of the plate-like workpiece (W) held by the workpiece holder (9) and the impeller (3) Rotate so that the center line of the projection direction coincides with the shot, and the shot projected from the impeller (3) is 90 degrees out of phase with the work holder (9) on the other spindle (8). It is easy to collide with the workpiece (W) of the attached workpiece holder (9) so that blasting (deburring) can be performed.

FIG. 4 shows a projection area (A) of a wide range projection type impeller in which the shape of a blade portion (not shown) is shaped like a “he” in the rotation direction so that the projection direction of the shot is widened. Compared with the direct projection type impeller described later, the impeller (3) has a wider shot projection area (A), lower projection density, and the incident angle of the shot projected onto the work (W) is smaller than 90 degrees. Since the work (W) is less damaged by the shot collision, the distortion of the work (W) is also reduced. The work holding unit (2) within the shot projection area (A) causes the work (W). By rotating and revolving, the workpiece (W) can be distorted efficiently and uniformly without any distortion.

FIG. 5 shows a projection area (A) of a direct projection type impeller in which the shape of a blade portion (not shown) is a flat plate and the shot projection direction is a straight traveling direction. Since the damage received by W) is larger than that of the wide-range projection impeller, the shot density and the projection speed corresponding to the deburring can be reduced by eliminating the distortion of the thin plate-like workpiece which is the object of the present invention. At the same time, if the number of the direct projection type impellers (3) to be installed is the number that can cover the area where the work (W) rotates and revolves by the work holding unit (2), and the shot can be projected simultaneously, Deburring the work (W) can be performed efficiently and uniformly.

  Hereinafter, conditions and results of Examples and Comparative Examples performed for confirming the effects of the present invention will be described.

The workpiece used in the example and the comparative example is a square case formed using an aluminum die cast product (ADC12 / JIS-H5302) having a plate thickness of 1.5 mm and a size of 190 × 170 × 30 mm, and an impeller (3 ) Was used a wide range projection type impeller shown in FIG.

The blasting (deburring) conditions of the example and the comparative example are shown in Table 1, but the difference between the example and the comparative example is that the rotational state of the workpiece (W) in the blast region (10) and the rotational speed thereof are different. In the work of the example, the ratio of revolution to rotation is 1: 3, and the rotation speed is revolution = 8 min−1, rotation = 24 min−1, whereas the work of the comparative example is rotation in which the rotation speed is 8 min−1. The other conditions are the same.

Next, with regard to the evaluation of workpiece distortion after blasting (deburring), the measurement method is to set the workpiece on a surface plate as shown in Fig. 6, and use Mitutoyo Corporation's "Height Gauge" as the measuring instrument. Then, before and after the blasting (deburring) processing, the working example and the comparative example were measured three times. As shown in FIG. 7, the measurement points are the four corners (a-1, a-2, b-1, b-2) of the workpiece, and the amount of change between the diagonal line (a) and the diagonal line (b) is the distortion. It was evaluated. The results are shown in Table 2.

The measured values of the measuring instrument shown in Table 2 are as follows. The workpiece (W) is set on the surface plate as shown in FIG. 6, and the four corners (a-1, a-2, b-1 and b-2) were measured using “Height Gauge” manufactured by Mitutoyo Co., Ltd. The evaluation of the distortion of the workpiece after blasting (deburring) according to the present invention was performed according to the workpiece of the example and the comparative example. (W) is prepared for each three, and the difference between the measured values at the four corners (a-1, a-2) and (b-1, b-2) is calculated with the diagonal line (a) of the workpiece (W) ( This is evaluated as the strain amount b).

Using a wide projection impeller for the impeller (3), the shot projection area (A) is wide, the projection density is low, the incident angle of the shot projected onto the work (W) is smaller than 90 degrees, and the distortion is reduced. Blasting (deburring) was performed under the same conditions as the shot projection with less occurrence, but as shown in Table 2, the distortion amounts of the diagonal lines (a) and (b) in the example were three workpieces. However, all of the three workpieces were satisfied with 0.3 mm or more, but the strain amount in the comparative example was all 0.3 mm or less. No result was obtained.

The top view which shows the relationship between the workpiece holding unit of this invention, and an impeller. The top view which shows the shot blasting apparatus of this invention. The perspective view of the workpiece holding unit of the present invention. Explanatory drawing which shows the projection area of a wide projection type impeller. Explanatory drawing which shows the projection area of a direct projection type impeller. Explanatory drawing which shows the method of the distortion measurement of a workpiece | work. Explanatory drawing which shows the distortion measurement position of a workpiece | work.

Explanation of symbols

1 Casing body 2 Work holding unit 3 Impeller 4 Axis of rotation A
5 Station disk 6 Rotating axis B
7 Turntable 8 Support shaft 9 Work holder 10 Blasting area 11 Work entry / exit area A Projection area W Workpiece

Claims (7)

A workpiece holding unit that holds a plate-like workpiece in a vertical state and rotates and revolves in the horizontal direction, and an impeller that projects a shot onto the workpiece are provided, and the workpiece is held by the workpiece holding unit during blasting A shot blasting device characterized in that the workpiece always rotates and revolves within the projection area of the impeller. A station disk that rotates horizontally around the rotation axis A as an axis center and a plate-like work is held vertically on the station disk so that the work rotates and revolves in the horizontal direction. A workpiece holding unit and an impeller that projects a shot onto the workpiece on one side of the casing body are provided, and the workpiece being blasted and held by the workpiece holding unit always rotates and revolves within the projection area of the impeller. A shot blasting device characterized by that. The work holding unit has a rotating disk that revolves in the horizontal direction about the rotating shaft B, a plurality of supporting shafts that are erected on the rotating disk so as to be capable of rotating, and a plate-like work that is provided on the supporting shaft. 3. The shot blasting apparatus according to claim 1, further comprising a work holder that can be loaded and unloaded and is held in a vertical state. At the position where the workpiece holder revolves and is closest to the impeller, the surface of the plate-like workpiece (W) held by the workpiece holder and the projection direction center line of the impeller (3) coincide with each other. 4. The shot blasting apparatus according to claim 3, wherein the work holder is rotated. The shot blasting apparatus according to claim 3 or 4, wherein one or a plurality of workpiece holders are provided on the support shaft. The shot according to any one of claims 3 to 5, wherein the work holder is composed of a net cage formed of a wear-resistant wire or a frame body formed of a wear-resistant bar. Blasting device. In the deburring process formed on a workpiece made of a plate material having a thickness of 2.0 to 0.3 mm, the plate-like workpiece is held in a vertical state in the casing body so as to rotate and revolve in the horizontal direction. A workpiece holding unit and an impeller that projects a shot onto the workpiece on one side of the casing body are provided, and the workpiece being blasted and held by the workpiece holding unit always rotates and revolves within the projection area of the impeller. The shot blasting device is used, and the processing conditions are as follows: shot projection speed: 30 to 60 m / sec, projection time: 60 to 180 sec, projection density: 4.5 to 7.5 Kg / m 2 · min A shot blasting method characterized in that the amount of strain generated in a workpiece by machining is 0.3 mm or less.