JPS6254616A - Cutter - Google Patents

Abstract

PURPOSE:To shift a cutter after a product all the time in deburring operations as well as to prevent it from biting into the product, by setting a cutter rectangular relief angle to an almost zero degree and a cutting angle to a range of 76 deg.-160 deg., respectively, while forming the whole cutter into an almost cylindrical form and setting the number of cutters to six in total. CONSTITUTION:A cutter rectangular relief angle means an angle of the back part of a cutter 2, that is, it means an angle crossing a tangent of a circle to be described by a tip of the cutter 2 and a line to be regulated by the back of the cutter 2. This relief angle is set to 0 deg. whereby the back part copies after a product part simultaneously with its rotation so that such a fear that the cutter 2 is in no case cut into the product part. A cutting angle, namely, angles alpha and beta made by each tip of cutters 2 and 4 are set to a range of 76 deg.-160 deg. whereby an optional angle is selectable according to material of a plastic mold, thus favorable deburring is performable.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a cutter suitable for deburring.

(Problems to be solved by conventional technology and the invention) In resin molded products, especially resin molded products that use a low-viscosity reaction liquid such as rim molding, flaking occurs from the mating surfaces of the molds. . ``In the past, the particles that appeared on resin molded products were often scraped off by workers using small force. Additionally, in some cases, a reamer is used to remove the burrs.

As shown in Fig. 6, the reamer used for this deburring process is the same as the reamer 41 used for metal materials, so if this reamer 41 is used, the work must be done carefully. 42 may dig into the product part, resulting in product defects. Therefore, this work required considerable skill and care.

Further, the reamer 41 has a groove 43 between the blades 42.
is formed to have a V-shaped cross section, etc., and a crack prevention groove 44 having a circular cross section is formed at the bottom of the groove 43, so that the scraped off particles tend to accumulate in the groove 44. Sometimes it was necessary to take the Paris.

The present invention is intended to overcome the above-mentioned problems, and aims to provide a cutter suitable for deburring that can reliably remove deburrs without digging into product parts.

Structure of the Invention (Means for Solving the Problems) Therefore, in order to solve the above problems, the present invention provides at least one blade with a normal clearance angle of approximately 0 degrees and a cutting angle of 76 degrees to 160 degrees. We employ the means we have in place.

(Function) When a blade whose clearance angle is approximately 0 degrees comes into contact with a paring part, the back of the blade always follows the product part, which prevents the blade from digging into the product part. , the cutting angle is 7
Since the blade is provided at any angle from 6 degrees to 160 degrees,
Depending on the hardness of the material of the resin molded product and the rotational speed of the air tool, etc., a blade with a cutting angle suitable for the hardness and rotational speed can be selected.

(First Embodiment) Hereinafter, an embodiment in which the present invention is applied to a reamer for removing the burrs of a rim-molded urethane resin molded product will be described with reference to FIGS. 1 to 3.

This deburring reamer 1 has a total length of 110 mm, a blade portion length of about 80 fins, and a diameter of 12 mm, and six blades 2 are formed on its side. The back of each moon 2 is on the same radius with respect to the center O. That is, the arc AB of the back part of the blade 2? Well, the radius is AO, it is on the circumference with the center as O, and the clearance angle perpendicular to the blade is 0 degrees.

Here, the blade normal clearance angle refers to the angle of the back of the blade 2, and refers to the angle at which the tangent to the circle drawn by the tip of the blade 2 and the line defined by the back of the blade 2 intersect. Therefore, when the blade normal clearance angle is 0 degrees, it means that the back part of the blade 2 is at the same distance from the center axis of the deburring reamer 1, and in this example, the circumference with the center as O It will be above.

The cutting angle (angle EAB) α of the blade 2 is 90 degrees, and the groove 3 formed between each groove 2 has a square cross section, the width of the opening (line segment AK) is 3 fins, and the depth AE. is 311. Further, a second blade 4 having a cutting angle of β may be formed on the opposite edge of the blade 2.

The blade to be used can be selected depending on the rotational speed of the reamer 1.

Here, the cutting angle refers to the angle formed by the tips of the blades 2 and 4. Therefore, in this embodiment, the angle α.

Becomes β.

Note that the bottom of groove 3 is the angle of both corners, angle AEF.

The angle KFE was set to 90 degrees.

Next, the results of using this deburring reamer 1 to remove deburrs generated on the inner and outer side surfaces of a urethane resin steering wheel molded by rim molding are described along with its effects. do.

That is, as shown in FIG. 3, this reamer 1 is attached to a device 221 that rotates at a high speed of 10,000 rotations per minute, and the first blade 2 is rotated clockwise in FIG. I did some work.

Furthermore, the reamer 1 was held perpendicular to the rotating shaft, and the burr 23 of the steering wheel 22 was placed on the side of the reamer 1 to remove the burr. At this time, since the relief angle of the back part of the blade 2 is set to approximately 0 degrees, the back part always follows the product part as it rotates. Therefore, the blade 2 did not dig into the product part, and deburring could be performed reliably and with a smooth cut surface.

In addition, when reamer 1 is attached to a near rotor and used at a low rotation speed of 3000 to 5000 times/min,
A reamer 1 having blades with a small cutting angle may be used. For example, when the rotation speed is 3000 rpm, a blade with a cutting angle of 76 degrees is used.

In this case as well, since the back of the blade traced the product part as in the case of high-speed rotation, the blade did not dig into the product part, and the deburring process resulted in a smooth cut surface.

The reason why the blade is used at low rotation speeds is to prevent the case where the cut surface cannot be made smooth if the rotation speed of the reamer 1 is slow and the 90-degree blade 2 is used. This does not indicate that 2 cannot be used. Therefore,
This is the case when a blade with a cutting angle of 76 degrees is used, and the cutting angle is 90 degrees.
Even if the blade 2 is used, no particular problem will occur.

In addition, the normal rotation speed, that is, 6000 to 9000 times/
When using the blade at a rotational speed of 1000 mm, using a blade with a different cutting angle as described below will allow for more reliable deburring with a smoother cut.

That is, when used for deburring relatively hard resins such as ABS resin and AAS resin, a blade with an acute cutting angle of 76 degrees to 89 degrees is used, and when using relatively soft resins such as urethane resin and PVC resin, a blade with an acute cutting angle of 76 degrees to 89 degrees is used. When used for deburring work, it is preferable to use a blade having an obtuse cutting angle of 90 to 160 degrees.

As described above, according to this embodiment, the normal clearance angle of the blade is set to 0 degrees, and a reamer with a blade with a cutting angle of 90 degrees is used to remove burrs at low rotation speed from urethane resin, which is a relatively soft resin. This prevents the product from digging into the product, so the operator does not need to be as careful as in the past, and is therefore very easy to handle and suitable for deburring.
1 can be provided.

In addition, since this deburring reamer 1 is held perpendicular to its rotation axis and the product to be deburred is placed on the side thereof, the removed burr 23 is discharged downward from the /*3 part.
It is possible to prevent the particles 23 from accumulating in the groove 3.

Note that the present invention is not limited to the above embodiments,
For example, it is also possible to embody it as follows.

(1) In this embodiment, the present invention was applied to remove the flakes from urethane resin, but the present invention is not limited to this, and can be applied to any synthetic resin product such as polyethylene or polypropylene.

(2) The blade portion is not limited to the numerical values and shape of this embodiment, and may be, for example, a blade 11 as shown in FIG. 4 or a blade 12 as shown in FIG. 5.

(3) The blade 2 of the cutter (reamer 1) is not limited to a straight line extending parallel to the axial direction, but may be twisted.

Effects of the Invention As detailed above, the cutter of the present invention has a clearance angle at right angle to the blade of approximately 0.
The cutting angle has been changed from 76 degrees to 160 degrees, so the blade can always be moved following the product during work such as deburring, thereby preventing the blade from digging into the product. It has excellent effects.

[Brief explanation of the drawing]

1 to 3 show a first embodiment of the present invention, FIG. 1 is a front view thereof, FIG. 2 is an enlarged bottom view thereof, and FIG. 3 is a deburring reamer of this embodiment attached to a deburring device. FIG. 4 is an enlarged bottom view showing another example, FIG. 5 is an enlarged bottom view showing another example, and FIG. 6 is an enlarged bottom view showing a conventional beam. Blade; 2 Patent applicant: Toyoda Gosei Co., Ltd. Agent
Patent Attorney On 1) Hironobu Uga, Commissioner of the Patent Office
Michibe Tono 28 Name of the invention Cutlery (name) Representative Nemoto Ingenuity 7. Insert the statement "3. Detailed explanation of the invention" between lines 11 and 12 of page 1 of the specification of contents of the amendment. do.

Claims (1)

[Claims] 1. The clearance angle at right angle to the blade is approximately 0 degrees, and the cutting angle is from 76 degrees to 16 degrees.
A cutlery characterized by having at least one 0 degree blade (2). 2. The blade has a generally cylindrical shape as a whole and has six blades,
The cutter according to claim 1, wherein the groove (3) between each blade (2) has a U-shaped cross section or a U-shaped cross section.