Rubber cutting machine drum blade tooth structure and design method thereof

Abstract

The present invention discloses a rubber cutter drum blade tooth shape structure and a design method thereof, which is characterized in that: it comprises a rake face and a flank face, the ends of the rake face and the flank face are provided with blade segments, the rake face is a long epicycloid, and the flank face is an involute. The rubber cutter drum blade tooth shape structure and the design method thereof of the present invention have a simple structure and reasonable arrangement, can effectively solve the problem of blade sticking when the rubber cutter drum is working, ensure the normal operation of the rubber cutter, and have a good application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber processing, and more specifically, relates to a rubber cutting machine drum blade tooth structure and a design method thereof. Background Art

[0002] Rubber cutting machines are widely used in production enterprises that use rubber as raw materials, such as tire factories, modified asphalt factories, waterproof material factories, self-adhesive factories, masking rubber factories and rubber research units. It is used to pre-slice large rubber blocks, and then perform subsequent crushing, processing or weighing. It is the previous step in rubber processing and production. The cutting efficiency of this step will affect the production efficiency of the entire production process. There are two types of existing rubber cutting machines. One is the guillotine type, that is, the cutter moves up and down, cuts downward, resets upward, and then the rubber block moves one position toward the blade to continue cutting. Its cutting efficiency is very low; the other is the drum type, which cuts the block rubber into slices through a rotating drum knife (rotor) and a drum (stator) that forms a match with it. Since the entire cutting process is related to the size and speed of the drum, its cutting efficiency is very high. This technology is still in the exploratory stage at home and abroad, and the product has not yet matured. In practice, it is found that there are also many problems, the main problem is the "sticking knife" phenomenon. That is, during the cutting process, the cut rubber sheet is still adhered to the toothed groove of the roller knife and cannot fall off, resulting in the inability to proceed to the next step of cutting.

[0003] The tooth shape of the drum cutter in the prior art is generally composed of straight line segments and arc segments. If a reasonable tooth shape cannot be formed, there will be no suitable cutting force, which will cause "knife sticking" in severe cases. There are two types of knife sticking. One is that the rubber block cannot be cut and is stuck between the drum rotor and the stator; the other is that the rubber block can be cut but cannot be discharged, that is, the cut rubber block cannot be separated from the tooth groove of the drum cutter under the action of the centrifugal force and gravity generated when the drum rotor rotates. This knife sticking phenomenon often occurs on the drum rubber cutter, and once it occurs, the rubber cutter will not work. Summary of the invention

[0004] The purpose of the present invention is to solve the problems existing in the prior art and to provide a rubber cutter drum knife tooth structure and a design method thereof which has a reasonable structural setting and can effectively solve the problem of knife sticking when the rubber cutter drum is working.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: the provided rubber cutting machine drum knife tooth structure is characterized in that it includes a front blade face and a rear blade face, and the ends of the front blade face and the rear blade face are provided with a blade segment, the front blade face is a long epicycloid, and the rear blade face is an involute.

[0006] To make the above technical solutions more detailed and specific, the present invention further provides the following more preferred technical solutions to obtain satisfactory practical effects:

[0007] The roots of the front cutting face and the rear cutting face are tooth root circles with a diameter of R1, the cutting edge section is located at the tooth top circle with a diameter of R3, and a tooth face middle diameter circle with a diameter of R2 is selected between the tooth root circle and the tooth top circle; the moving circle on the middle diameter circle rolls purely along the outer circle of the fixed circle with a middle diameter of R2, and the movement locus formed by a point on the tooth root circle outside the moving circle constitutes the front cutting face; the rear cutting face is formed with the tooth root circle with a diameter of R1 as the base circle.

[0008] The cutting edge section is arc-shaped, and the arc length is 0.2 - 1.5 mm.

[0009] The diameter of the arc of the cutting edge section is the diameter R3 of the tooth top circle.

[0010] The diameter R2 of the middle diameter circle is 50 mm to 200 mm.

[0011] The diameter R3 of the tooth top circle is not less than 1.2R2 and not greater than 1.4R2.

[0012] The diameter R1 of the tooth root circle is not less than 0.6R2 and not greater than 0.8R2.

[0013] The rectangular coordinate parametric equation of the front cutting face is as follows:

[0014] X = Psin(2Ф) – KsinФ;

[0015] Y = KcosФ - Pcos(2Ф);

[0016] Where Ф - the rotation angle of the moving circle, 30° < Ф < 45°; K - the distance between the centers of the fixed circle and the moving circle; P - the distance from the center of the moving circle to point C.

[0017] The rectangular coordinate parametric equation of the rear cutting face is as follows:

[0018] X = a*(cos(t) + rad(t)*sin(t));

[0019] Y = a*(sin(t) - rad(t)*cos(t));

[0020] Where: t - the development angle, 60° < t < 130°; a - the radius of the base circle.

[0021] The spiral angle of the tooth profile of the drum cutter is 2 - 10 degrees.

[0022] Compared with the prior art, the present invention has the following advantages: the rubber cutter drum knife tooth structure and design method of the present invention are simple in structure and reasonably arranged, which can effectively solve the problem of knife sticking when the rubber cutter drum is working, ensure the normal operation of the rubber cutter, and have good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The following is a brief description of the contents and symbols in the drawings of this specification:

[0024] Figure 1 This is a schematic diagram of the curved structure of the roller blade teeth of the present invention;

[0025] Figure 2 It is a cross-sectional schematic diagram of the rubber cutting machine when the present invention is used for rubber slicing;

[0026] Figure 3 This is a cross-sectional schematic diagram of a drum cutter with four cutter teeth in the first embodiment;

[0027] Figure 4 This is a second embodiment, a schematic cross-sectional view of a drum knife with three teeth.

[0028] Marked in the figure: 1, entrance, 2, roller knife, 3, roller. DETAILED DESCRIPTION

[0029] The specific implementation modes of the present invention will be further explained in detail below through the description of embodiments with reference to the accompanying drawings.

[0030] The rubber cutting machine drum blade tooth structure of the present invention comprises a rake face and a flank face, and the ends of the rake face and the flank face are provided with blade segments, the rake face is a long epicycloid, and the flank face is an involute. Figure 1 As shown, the tooth curve of the roller knife tooth structure is composed of the tooth curves ABCDEFG on the cross section of the roller knife, A and G are on the tooth top circle, B and F are on the tooth surface middle diameter circle, C, D and E are on the tooth root circle, and the characteristic is that the curve ABC is the front cutting face of the tool, and its cross-sectional tooth shape is a long epicycloid, EFG is the back cutting face of the tool, and its cross-sectional tooth shape is an involute, and the arc segment AG is the blade segment.

[0031] Curve ABC is a long epicycloid, which serves as the front cutting edge of the roller knife. This long epicycloid is formed as follows: when the moving circle on the middle diameter circle rolls purely along the outer circle of the fixed circle with a middle diameter R2, it forms a motion trajectory with a point C outside the moving circle.

[0032] The rectangular coordinate parameter equation of the long-amplitude epicycloid ABC is as follows:

[0033] X=Psin(2Ф)–KsinФ;

[0034] Y = KcosФ - Pcos(2Ф);

[0035] where Ф is the rotation angle of the moving circle, 30° < Ф < 45°. When the addendum circle diameter R3 is 1.2R2, the value of the rotation angle Ф of the moving circle is close to 45°. When the addendum circle diameter R3 is 1.4R2, the value of the rotation angle Ф of the moving circle is close to 30°;

[0036] K is the distance between the centers of the fixed circle and the moving circle;

[0037] P is the distance from the center of the moving circle to point C;

[0038] The diameter of the moving circle is the same as the pitch circle diameter. Point C is a point on the root circle and serves as the starting point of the involute.

[0039] In the present invention, EFG is an involute, which serves as the flank of the drum cutter. This involute is formed with the root circle with a diameter of R1 as the base circle. That is, the locus of any point on a moving straight line (generating line) during the process of rolling along a fixed circle (base circle R1).

[0040] The rectangular coordinate parametric equation of the flank is as follows:

[0041] X = a*(cos(t) + rad(t)*sin(t));

[0042] Y = a*(sin(t) - rad(t)*cos(t));

[0043] where: t is the involute angle, 60° < t < 130°. When the root circle diameter R1 is 0.6R2, the value of the involute angle t is close to 130°. When the root circle diameter R1 is 0.8R2, the value of the involute angle t is close to 60°; a is the base circle radius.

[0044] The arc segment AG is the cutting edge of the drum cutter. Preferably, the arc length is 0.2 - 1.5 mm, which coincides with the circumference of the addendum circle with a diameter of R3. When point A coincides with point G, the arc length of the cutting edge is 0, and at this time, the cutting edge is the sharpest, but the wear resistance is poor. When the arc length of the cutting edge is 0.2 - 1.5 mm, it can ensure a certain wear resistance during cutting.

[0045] The preferred parameter range is as follows:

[0046] Pitch diameter R2 (protection range): 50 ≤ R2 ≤ 200

[0047] Addendum circle diameter R3: 1.2R2 ≤ R3 ≤ 1.4R2

[0048] Root circle diameter R1: 0.6R2 ≤ R1 ≤ 0.8R2

[0049] Arc length of arc segment AG: 0.2 - 1.5 mm

[0050] The present invention can be made into a left-handed roller knife or a right-handed roller knife. The preferred helical angle is 2 to 10 degrees, which can obtain a better rubber cutting and discharging effect.

[0051] like Figure 2 As shown in the figure, the front blade surface of the rubber cutting machine drum blade tooth shape is a long epicycloid, and the rear blade surface is an involute. When the rubber cutting machine is working, the drum blade 2 acts as a rotor and rotates clockwise, and the drum 3 acts as a stator and is fixed. When the rubber block is put into the inlet 1, the rubber block is cut off and falls (thrown out) from the bottom 3 under the shear force formed by the drum blade 2 and the drum 3.

[0052] In the present invention, a plurality of blade teeth can be arranged in the circumferential direction of the drum blade. The present invention provides two embodiments, in which four or three blade teeth are arranged, and the tooth curves are respectively Figure 3 and Figure 4 as shown in .

[0053] Embodiment 1:

[0054] The embodiment of the four tooth shapes of the drum cutter cross section of the present invention is shown in FIG. Figure 3 , the median diameter is 100mm;

[0055] The diameter of the tooth tip circle is 1.3 times the median diameter, which is 130 mm.

[0056] The root diameter is 0.7 times the median diameter, which is 70 mm.

[0057] The arc length of arc segment AG is 1.2 mm.

[0058] Embodiment 2:

[0059] The embodiment of the three tooth shapes of the cross section of the drum knife of the present invention is shown in FIG. Figure 4 , the median diameter is 50mm;

[0060] The diameter of the tooth tip circle is 1.2 times the median diameter, which is 60 mm.

[0061] The root diameter is 0.8 times the median diameter, which is 40 mm.

[0062] The arc length of arc segment AG is 0.5 mm.

[0063] Experiments have confirmed that when the roller blade tooth shape designed by the present invention is applied to a roller rubber cutting machine, no blade sticking phenomenon is found.

[0064] The mechanism of the tooth profile curve ABCDEFG as the roller cutter tooth profile is that the curve can form a cutting edge, a continuous material receiving area with basically no dead angle transition, and sufficient cutting strength of the cutter teeth. For the front cutting edge, since a specific long epicycloid ABC is used and point C is located on the tooth root circle CDE, the curve can intersect with the tooth top circle to form a cutting edge and has an arc with a smooth transition at the root. On the other hand, EFG is an involute used as the rear cutting edge of the roller cutter tooth profile, and its curve base circle starting point E is located on the tooth root circle CDE. Moreover, the cutter teeth formed by the combination of the involute and the long epicycloid have sufficient cutting strength. Therefore, a tooth profile curve formed by the long epicycloid ABC, the arc CDE and the involute EFG constitutes a cutting edge, a continuous material receiving area with basically no dead angle transition, and sufficient cutting strength of the cutter teeth.

[0065] The present invention provides a rubber cutter drum blade tooth shape to solve the problem of blade sticking during operation of the rubber cutter drum. The drum blade tooth shape of the present invention is adopted to avoid blade sticking. Curve ABC is a long epicycloid, which realizes the most ideal rake face angle. During the cutting process, the rubber block can be cut off and smoothly thrown out under the action of centrifugal force and gravity, thus perfectly realizing the cutting of the rubber block. EFG is an involute, which is combined with curve ABC to realize an ideal working tooth shape.

[0066] The positive effect of the present invention is that its tooth curve has good rubber slicing characteristics. The use of the roller knife with the tooth shape for cutting rubber can achieve the goal that the rubber block does not stick to the knife during the working process, thereby achieving stable and reliable operation of the equipment.

[0067] The rubber cutter drum knife tooth shape structure and design method thereof of the present invention have simple structure and reasonable arrangement, can effectively solve the problem of knife sticking when the rubber cutter drum is working, ensure the normal operation of the rubber cutter, and have good application prospects.

[0068] The present invention is described above by way of example in conjunction with the accompanying drawings, but the present invention is not limited to the above manner. As long as various non-substantial improvements made using the method concept and technical solution of the present invention or direct applications to other occasions are made, they all fall within the protection scope of the present invention.

Claims

1. A design method for a rubber cutting machine drum blade tooth structure, characterized in that: The tooth profile structure of the cutting rubber machine drum knife includes a front cutting surface and a rear cutting surface. The end parts of the front cutting surface and the rear cutting surface are provided with cutting edge segments. The front cutting surface is a long amplitude epicycloid, and the rear cutting surface is an involute. The design method of the tooth profile structure of the cutting rubber machine drum knife: at the roots of the front cutting surface and the rear cutting surface is a root circle with a diameter of R1, the cutting edge segment is located at the tip circle with a diameter of R3, and a pitch circle with a diameter of R2 is selected between the root circle and the tip circle; a moving circle on the pitch circle rolls purely along the outer circle of a fixed circle with a diameter of R2, and the movement locus formed by a point on the root circle outside the moving circle constitutes the front cutting surface; the rear cutting surface is formed with the root circle with a diameter of R1 as the base circle; the rectangular coordinate parameter equation of the front cutting surface is as follows: X = Psin(2Ф)–KsinФ; Y = KcosФ - Pcos(2Ф); where Ф - the rotation angle of the moving circle, 30° < Ф < 45°; K - the distance between the centers of the fixed circle and the moving circle; P - the distance from the center of the moving circle to point C; point C is a point on the root circle and is used as the starting point of the involute.

2. The method for designing the tooth-shaped structure of the rubber cutting machine drum according to claim 1 is characterized in that: The cutting edge segment is arc-shaped, and the arc length is 0.2~1.5mm.

3. The method for designing the tooth-shaped structure of the rubber cutting machine drum according to claim 2 is characterized in that: The arc diameter of the cutting edge segment is the tip circle diameter R3.

4. The method for designing the tooth-shaped structure of the rubber cutting machine drum according to any one of claims 1 to 3, characterized in that: The pitch circle diameter R2 is 50mm to 200mm.

5. The method for designing the tooth-shaped structure of the rubber cutting machine drum according to claim 4 is characterized in that: The tip circle diameter R3 is not less than 1.2R2 and not more than 1.4R2.

6. The method for designing the tooth-shaped structure of the rubber cutting machine drum according to claim 5 is characterized in that: The root circle diameter R1 is not less than 0.6R2 and not more than 0.8R2.

7. The method for designing the tooth-shaped structure of the rubber cutting machine drum according to claim 6, characterized in that: The rectangular coordinate parameter equation of the rear cutting surface is as follows: X = a*(cos(t)+rad(t)*sin(t)); Y = a*(sin(t)-rad(t)*cos(t)); where: t - the developed angle, 60° < t < 130°; a - the base circle radius.

8. The method for designing the tooth-shaped structure of the rubber cutting machine drum according to claim 1 is characterized in that: The spiral angle of the drum knife tooth profile is 2~10 degrees.

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