KR200309369Y1 - Apparatus for manufacturing rotary blade for use in agricultural machines - Google Patents

Abstract

The present invention relates to a manufacturing apparatus for manufacturing a rotary blade mounted on a farming machine such as a tiller or a tractor, the material supply unit (1) for pushing the laminated material one by one with a push rod 15 at regular intervals, and the material 800 After heating to ˜900 ° C., the material introduced between the heating unit 2 closely contacting one side of the discharge groove 25 through the material sorter 26 and the pair of rolling rollers 35 and 35 'is blade-shaped. Fixed with a rolling section 3 to be rolled with a roll, a material conveying section 4 for conveying the material to the rotary conveying plate 41 and the conveying table 47, and a forceps plate 56 of the rotating table 52 rotating left and right. A rotary mounting portion 5 for mounting and rotating the rolled material by installing the tongs 57, a bending roller 62 in which the material is in contact with the arc-shaped moving line of the material attached to the rotation mounting portion 5, and up and down Bending rolling section 6 for bending the material and forming the blade through the symmetrically installed blade roller (63, 63 ') and And a press part 7 for installing a pair of robot arm feeders 71 and 71 ′ and picking up the material into the punching mold 72 and the drawing mold 73 in order to process them, and the press part 7. By receiving the material discharged from the) through the discharge conveyor 81 is composed of a reheat treatment unit for heat treatment again to the heating furnace 21, by heating the material cut to a predetermined size in accordance with the shape of the rotary blade from the supply, A series of processes ranging from rolling, banding, forming, pressing, drawing, and reheating can be performed sequentially and continuously to produce large quantities of high-strength, high-quality products with minimal manpower and optimized production lines.

Description

Apparatus for manufacturing rotary blade for use in agricultural machines

The present invention relates to a manufacturing apparatus for manufacturing rotary blades mounted on agricultural machinery such as cultivators and tractors, and more specifically, supplying, heating, rolling, banding, cutting, A series of work processes such as pressing, drawing, and reheating were carried out continuously to enable mass production of rotary blades.

In general, rotary blades mounted on agricultural machinery used for attaching to cultivators or tractors are mainly used to dig soil, turn over, flatten the surface of overturned soil, or grind soil to remove weeds. As the range of use is wide and various types are used, not only they rub against the soil by high-speed rotation, but also often collide with the stones mixed in the soil, so they must have high durability in order to use them for a long time under these conditions. Therefore, it should be manufactured using a high strength material.

However, the general shape of the rotary blade is not only because the blade is formed on one side as shown in the figure, but also the manufacturing process is very complicated because it has to be manufactured in a unique shape with curvature in order to dig the soil easily. Even in the process of manufacturing rotary blades, many people manually carry out the manual work, and some processes may be out of hand by some degree due to the development of manufacturing technology. Since it is not realized, productivity is greatly reduced, and a lot of labor costs are input according to the performance of manual labor, resulting in an increase in manufacturing cost.

The present invention was developed in order to solve the above-mentioned conventional problems, a material supply part for supplying the conveyor and conveying the material cut in the form of a rotary blade and a plurality of materials sequentially and then supplying each one, and the supplied material Pressing again the heating part which heats to the temperature required for rolling processing, the rolling part which rolls a heated material to the thickness suitable for a blade shape, the bending rolling part which forms a sharp blade part while bending a rolled material, The press part for drawing and drawing and the reheating part for heat treatment of the finished material can be sequentially arranged to enable the continuous production of rotary blades for farm machinery, while minimizing manpower required for production to reduce production costs. When described in more detail by the accompanying drawings as follows. .

1 is a configuration of the heating, rolling, material transfer, bending rolling in the material supply of the present invention

Plan view shown

Figure 2 shows the configuration of the bending and pressing section, the reheating unit of the present invention

Flat illustration

Figure 3 is an exemplary side view showing a material supply portion and a heating portion of the subject innovation

Figure 4 is an exemplary side view showing a rolled part of the present invention

Figure 5 is a plan view showing a rolling part of the present invention

6 is an exemplary view showing a material transfer part between the rolling part and the banding rolling part of the present invention

7 to 9 is an exemplary view showing an operation process of the material transfer unit of the present invention

10 is a plan view showing a material processing process by the bending rolling unit of the present invention

11 is a perspective view of the bending rolling unit of the present invention

12 is an exemplary view showing an operation process of the blade forming roller of the bending rolling part of the present invention.

Figure 13 shows the state arranged symmetrically the main production line of the subject innovation

It is a block diagram.

* Explanation of symbols for the main parts of the drawings

1: material supply unit 11: conveyor

12: supply table 13: material stacking part

14: injection cylinder 14a: loading table

15: rod 18: loading table

2: heating part 21: heating furnace

22: discharge roller 23: push rod

25: discharge groove 26: material sorter

3: rolling part 31: reducer

32: universal joint 33: drive motor

34: air clutch 35: rolling roller

36: catcher 38: lifting rod

4: material transfer part 41: rotation transfer plate

41b: Guard 42: Jamming

43: rotation axis 44: rotation means

45: base 46: material fixing

47: transfer table 48: transfer plate

49: fluid pressure cylinder 5: rotational mounting

51: moving table 52: rotating table

53: fluid pressure cylinder 54: molding groove

55: fixing groove 56: clip plate

57: fixing forceps 6: banding rolling section

61: information board 62: banding roller

63, 63 ': Blade forming roller 64, 64': Gear

65 fluid pressure cylinder 7 press part

71, 71 ': robot arm transfer machine 72: punching mold

73: drawing mold 8: reheating unit

81: discharge conveyor 82: reheating furnace

A conveyor 11 for transporting a plate-shaped material cut in a rotary blade shape is provided, and a supply stand 12 having a loading table 18 and a material stacking portion 13 is formed at an end thereof. A material supply unit (1) for pushing the materials stacked on the (13) to the push rod (15) operated by the injection cylinder (14) and the fluid pressure cylinder (16) one by one, and to be supplied at regular intervals;

A roller driven by a motor is installed at the end of the high-frequency heating furnace 21 that heats the material introduced therein at 800 to 900 ° C., and a pusher 23 reciprocating by the fluid pressure cylinder 24 is installed at the lower part of the roller. A heating part 2 installed and closely contacting the material conveyed along the discharge groove 25 by the pusher 23 to one side of the discharge groove 25 through the material sorter 26;

By arranging a pair of rolling rollers 35 and 35 ', the rotary shaft 35a of each rolling roller 35 and 35' is connected to the output shaft 31b of the reduction gear 31 and the universal joint 32. The shaft holder 36 of the upper rolling roller 35 is connected to the lifting rod 38 of the fluid pressure cylinder 37 installed on the upper portion of the upper roller, and the air clutch 34 is provided at the driving unit of the reducer 31. A rolling part 3 for rolling the material introduced between the rolling rollers 35 and 35 'into a blade shape;

The rotary shaft 43 formed integrally with the rotary transfer plate 41 on which the raw material is loaded by the rotating pedestal 45 and the locking protrusion 42 is rotated using the rotating means 44 to advance and retreat by the transfer table 47. A material transfer part 4 for loading a material on an upper portion of the transfer plate 48, and pushing the material with a push rod formed in the transfer table 47 advancing and receding by the fluid pressure cylinder 49;

Lacquer reciprocating by the fluid pressure cylinder 53 by installing the swivel wheel 52 having the rotary gear 52a formed on the upper part of the movable bed 51 moving along the guide 51a by the fluid pressure cylinder 51b. The gear 53a and the rotary gear 52a are engaged to rotate the rotating table 52 to the left and right, and an arc-shaped forming groove 54 is formed at one side of the upper surface of the rotating table 52 to form a fluid pressure cylinder 53 thereon. A clamping plate 56 pressurized by), and on one side thereof, a fixing clamp 57 which is operated by the fluid pressure cylinder 56a to install and roll the rolled material to rotate.

A blade forming roller (63) (63 ') is installed between the upper and lower guide plates (61) between the upper and lower guide plates (61) to contact the material along the arc-shaped moving line of the material attached to the rotary mounting (5). Gears 64 and 64 'formed at each end of the rotation shaft are engaged with each other, but gears 64 and 64' on one side are engaged with the rack gear 65a reciprocating to the fluid pressure cylinder 65 to form a material. Banding rolling section (6) for bending and forming the blade

A pair of robot arm feeders (71, 71 ') are installed, and the robot arm feeder (71) on one side picks up the material processed by the bending rolling section (6) and punches a mold (72) having an alignment cylinder (72a). And the other side robot arm feeder 71 ', the press part 7 which inverts the material of the punching die 72 and puts it into the drawing mold 73, and discharges the finished material.

The material is supplied through the discharge conveyor 81 is composed of a reheat treatment unit for heat treatment again to the reheating furnace (82).

When explaining the embodiment of the present invention as described above by the drawings as follows.

First, Figures 1 to 2 is a plan view showing the whole configuration of the present invention divided by first drawing Figure 1 shows the configuration of the heating, rolling, banding rolling part 6 in the material supply corresponding to the front configuration of the present invention 2 is a diagram showing the configuration of the bending rolling section 6 and the press section 7, the operation of each device is generally appropriately arranged for devices such as position sensors, limit switches, time switches, etc. All devices that perform this operation are installed to repeat the continuous operation in conjunction with the correct timing.

3 is an exemplary side view showing the material supply unit 1 of the present invention, which is loaded on the conveyer through the conveyor 11 by installing a loading table 18 on which a plurality of materials are loaded, as shown in the drawing. As the worker stacks a plurality of materials on top of the mounting table 18, the work can be performed more easily when the materials are aligned and stacked on the material stacking portion 13 formed on one side of the supply table 12. Will be.

In addition, an input is formed at a lower end of the material stacking portion 13 formed on one side of the flat feeder 12 formed on the mounting table 18, and an injection cylinder 14 is installed at a side of the feeding groove. In this case, when a plurality of materials are stacked on the material stacking unit 13, an input plate 14a connected to the rod of the injection cylinder 14 is fed to the lower end of the material stacking unit 13 to supply one material at the bottom end thereof. In front of the push rod to advance along the longitudinal direction of).

Thus, when a single material is supplied to the front of the push rod provided on the upper side of the feed stand 12, the upper end of the feed stand 12 by the operation of the fluid pressure cylinder 16 for advancing back and forth the connecting rod 17 provided on the bottom of the push rod The push rod is pushed into the heating unit 2 by pushing the material located in front.

In the material supply part 1 of the present invention, the speed of supplying the material to the heating part 2 is preferably 5 to 6 per minute. For this purpose, a continuous supply of material is achieved by appropriately configuring a driving circuit and a position sensor. It is configured to be made.

On the other hand, the material supplied from the material supply unit 1 is introduced into the high frequency heating furnace 21 of the heating unit 2, the high frequency heating furnace 21 has a predetermined width of the passage formed therein along the material The material is heated to 800 ~ 900 ℃ during the transfer, when the heated material is discharged from the high-frequency heating furnace 21, the material is quickly discharged by the discharge roller 22 driven by the motor 22 Are conveyed up to).

As such, the material transferred to the discharge groove 25 is loaded with the spring discharged from the material sorter 26 fluid pressure cylinder 26a installed at one side of the discharge groove 25 as shown in FIGS. 4 to 5. While pushing the push rod 26b, the push rod 26b is brought into close contact with the side of the discharge groove 25 to align the materials, and together with the fluid pressure cylinder installed at the bottom of the heating unit 2, The pusher 23 advancing and retreating by 24 pushes the aligned material and supplies it to the rolling part 3.

Thus, the material supplied by the pusher 23 of the heating unit 2 is fed between a pair of rolling rollers 35 and 35 'arranged up and down and rolled into a blade shape by the rolling rollers 35 and 35'. do.

At this time, the rotary shaft 35a of the rolling rollers 35 and 35 'provided with a pair is connected to the output shaft 31b of the reducer 31 and the universal joint 32. The air shaft is connected to the drive shaft 31a of the reducer 31. The clutch 34 is installed and connected to the drive pulley 33a of the drive motor 33 by the belt, thereby intermittently rotating the rolling rollers 35 and 35 'as the air clutch 34 is interrupted. Energy loss due to unnecessary rotation can be minimized.

In addition, among the pair of rolling rollers 35 and 35 ', the upper rolling rollers 35 and 35' are installed on the upper side of the frame so that the shaft holder 36 can be elevated in the lifting guide of the base. It is connected to the lifting rod 38 of the fluid pressure cylinder 37, and is configured to be able to move up and down within the thickness range of the material in accordance with the operation of the fluid pressure cylinder 37 in the lifting guide portion, Since the rolling rollers 35 and 35 'are connected to the reducer and the universal joint 32, even if the upper rolling rollers 35 and 35' are elevated, the rolling rollers 35 and 35 'have a great influence on the rotation of the rolling rollers 35 and 35'. It will not go crazy.

In addition, the surface of the rolling rollers 35 and 35 'is formed to have a somewhat larger diameter so that the blade side of the rotary blade is more compressed, and is heated in the heating section 2 and then rolled in the rolling section 3. The blade is made to be rolled in accordance with the basic skeleton of the blade for the rotary blade thin and thick.

6 is a view illustrating a material transfer part 4 for transferring a material discharged after rolling in the rolling part 3 to the next process, and the material discharged from the rolling part 3 is rotated once as shown in the drawing. (41) It is loaded on the upper surface.

At this time, the rotary transfer plate 41 is integrally formed on the rotating shaft 43 which rotates in both directions by the rotating means 44, while being inclined to the height of the portion of the material discharged from the rolling rollers 35 and 35 '. When the material discharged is seated on the upper part of the rotary transfer plate 41, the material is slid down along the inclination of the rotary transfer plate 41. In this case, the material is prevented from being separated from the rotary transfer plate 41. In addition, not only the guard 41b is formed at the side surface of the rotary transfer plate 41, but a through hole 41a is formed at the center thereof, and the locking protrusion 42 formed at the base of the rolling part 3 is formed in the cylinder. Since protruding through the study (41a), the material that slipped down the inclination of the rotary transfer plate 41 is caught by the locking projection 42 is stopped.

In addition, in order to prevent the material that has slipped down the rotary feed plate 41 from being bounced off at the moment of being caught by the locking projection 42, it is rotated by a fluid pressure cylinder 45b provided on the upper surface of the base of the rolling part 3. A pedestal 45 protruding a predetermined length from the upper end of the rotary operating plate 45a is installed on one side of the rotating shaft 43 so that the pedestal 45 is formed by the fluid pressure cylinder 45b of the rotary feed plate 41. By positioning it from the front, it is possible to prevent the material that is sliding down the rotary transfer plate 41 to be separated from the rotary transfer plate 41.

When the material is correctly seated on the rotary feed plate 41 as described above, the fluid pressure cylinder 46a of the material holder 46 installed on one side of the rotation shaft 43 operates to push the fixing rod 46b to fix the rod ( After the 46b) is rolled, the one side of the discharged material is pushed to strongly adhere the material to the guard 41b on the side of the rotary transfer plate 41, and then the rotating shaft 43 is rotated at a predetermined angle by the rotating means 44. When the material is seated upside down on the upper surface of the transfer plate 48 located in front of the rotating shaft 43, after the material holder 46 releases the fixing of the material, the rotating shaft 43 is rotated in the opposite direction by the rotating means 44 again. By rotating the rotary transfer plate 41 is returned to its original position for the transfer of the next discharged material.

7 to 9 illustrate a process in which the material is transferred from the material conveying part 4 to the rotation mounting part 5, and seated on the upper surface of the conveying plate 48 installed at the end of the conveying table 47 as shown in FIG. 7. The raw material is conveyed to the vicinity of the rotation mounting part 5 while being seated on the conveying plate 48 while the fluid pressure cylinder 49 installed on one side of the frame of the rolling part 3 pushes the conveying table 47 forward. When the front of the transfer plate 48 is caught by the engaging piece installed on the upper surface of the movable stand 51 of the rotation mounting part 5, the movement of the transfer plate 48 is stopped, but the guide rod 47b formed on the transfer plate 48. The transfer table 47 installed to move forward and backward along the guide rod 47b of the transfer plate 48 by the fluid pressure cylinder 49 continues to move forward.

At this time, since the push rod protruding into the guide groove 48a formed in the transfer plate 48 is formed on the upper surface of one end of the transfer table 47 connected to the transfer plate 48, the transfer table 47 moves forward. The pusher 47a also moves forward along the guide groove 48a, and thus the material seated on the upper surface of the transfer plate 48 is transferred by the advancement of the pusher 47a, so that the front end of the material rotates. It is to be introduced into the fixing groove 55 formed in the rotary table 52 of 5).

Thus, when the material is inserted into the fixing groove 55 formed on the rotating table 52 by a sensor or the like, as shown in FIG. 6, the fixing clamp 57 installed in the transverse direction on the upper surface of the rotating table 52 has a fluid. It is operated by the pressing cylinder (57a) to fix one end of the material introduced into the fixing groove (55) to the correct position in the longitudinal direction from the upper portion of the tong plate 56, which is installed with the coil spring (56b) on the upper surface of the swivel table (52) As the rod of the installed hydraulic pressure cylinder 56a presses the forceps plate 56 downwardly, the forceps plate 56 bites and fixes the material introduced into the fixing groove 55 formed in the bottom of the forceps plate 56.

When the material is fixed to the swivel table 52 as described above, the movable table 51 is bent and rolled by the fluid pressure cylinder 51b which reciprocates the movable table 51 along the guide 51a to the bending rolling section 6. (6) A fluid pressure cylinder having a rod gear 53a engaged with a rotary gear 52a provided on the bottom of the swivel table 52 as shown in FIGS. The rotary table 52 rotates in the clockwise direction by the operation of 53).

Attached drawing Figure 10 shows a process in which the blade is sharply formed on one side while the bending process of the material is made by the rotation of the swivel 52, when the swivel 52 is rotated as shown in the drawing fixed the swivel 52 One side of the material fixed in the groove 55 is rotated in contact with the bending roller 62 installed between the upper and lower guide plates 61 of the bending rolling part 6, but the material is heated by the heating part 2. Since it is heated to a high temperature in the very soft state, the outer surface of the raw material is bent inward roller 62 is bent while the rotary table 52 is rotated.

This bending material is formed by contacting the molding grooves 54 formed inside the tongs plate 56 of the swivel table 52 to achieve the bending molding of the material. The blade forming rollers 63 and 63 'of (6) form a sharp blade on one side of the material.

In the above-described blade forming rollers 63 and 63 'of the bending rolling part 6, a pair of upper and lower symmetrical structures are installed as shown in FIGS. 10 to 12, and the rotating shaft protrudes to the rear of the roller. Gears 64 and 64 'are respectively installed in the gears, and two gears 64 and 64' are engaged with each other. The gears 64 and 64 'of the upper blade forming rollers 63 and 63' are connected to each other. A pair of blade forming rollers 63, 63 'installed in a symmetrical structure by a fluid pressure cylinder 65 for reciprocating the rack gear 65a rotates between the rollers while the size gear 65a is engaged. One side of the injected material is pressed to form a sharp blade on one side of the material.

When the bending and shaping of the material in the bending rolling part 6 is completed, the rod of the fluid pressure cylinder that presses the tongs plate 56 from the upper part of the swivel table 52 is raised to its original position by the coil spring 56b. When the coalesced tongs 56 are lifted up, the articulated robot arm feeders 71 and 71 'installed in the press unit 7 are fitted in the forming grooves 54 and the fixing grooves 55 of the swivel table 52. The material is picked up and placed on the punching die 72 of the press unit 7.

At this time, the alignment cylinder 72a is installed at one side of the punching die 72 of the press portion 7 to push the material into the punching die 72 to adjust the position precisely, and then the press descends to move the material to the exact position of the rotary blade. After cutting and punching to form, another robot arm feeder (71) (71 ') picks up the pressed material from the punching mold (72), turns the material over and puts it back on the drawing mold (73). When the press is lowered, the drawing of the rotary blade is completed by drawing the material laid down on the drawing mold 73 according to the shape of the bent rotary blade, and as mentioned above, in the present invention, the supply of ordinary materials is usually performed per minute. About 5 to 6 are suitable for all processes and devices by means of drive circuits designed for the supply time of these materials and various sensors and switches for automation. This is because the precise linkage made up of a rotary blade for mass production will be done.

Thus, the material completed by the drawing process is again conveyed by the robot arm transfer machine (71) (71 ') to pick up the material and to load it on the discharge conveyor (81) leading to the reheat treatment unit is transferred to the discharge conveyor (81) Heat treatment in the reheat treatment unit is completed for the rotary blade.

On the other hand attached to Figure 13 is a block diagram showing a state in which the main line for forming the blade in a symmetrical structure in order to utilize the manufacturing apparatus of the present invention more efficiently, as shown in the conveyor 11 for the supply of the first material Re-heating is followed by a discharge conveyor 81 for the discharge of the final material and all other product processing lines are arranged in a symmetrical structure to enable the operation of a more efficient manufacturing apparatus for mass production.

As described above, the present invention sequentially and continuously performs a series of processes from supplying a material cut to a predetermined size according to the shape of a rotary blade to heating, rolling, banding, forming, pressing, drawing, and reheating. As a result, it is possible to produce high-strength, high-quality products in large quantities through a minimum number of personnel and an optimized production line, which greatly improves the productivity of the product and lowers the production cost of the product, thereby producing an excellent product at a low cost.

Claims (2)

On one side of the supply conveyor 11 for conveying the material, a supply table 12 having a loading table 18 and a material stacking portion 13 is formed, and a material stacked on the material stacking portion 13 is injected into a cylinder ( 14) and the material supply unit (1) for pushing out one by one to the push rod 15, which is operated by the fluid pressure cylinder (16), and a predetermined period, A roller driven by a motor is installed at the end of the high-frequency heating furnace 21 that heats the material introduced therein at 800 to 900 ° C., and a pusher 23 reciprocating by the fluid pressure cylinder 24 is installed at the lower part of the roller. A heating part 2 installed and closely contacting the material conveyed along the discharge groove 25 by the pusher 23 to one side of the discharge groove 25 through the material sorter 26; By arranging a pair of rolling rollers 35 and 35 ', the rotary shaft 35a of each rolling roller 35 and 35' is connected to the output shaft 31b of the reduction gear 31 and the universal joint 32. The shaft holder 36 of the upper rolling roller 35 is connected to the lifting rod 38 of the fluid pressure cylinder 37 mounted on the upper portion of the upper roller, and the air clutch 34 is provided to the driving unit of the reducer 31 by a pair. A rolling part 3 for rolling the material introduced between the rolling rollers 35 and 35 'into a blade shape; The rotary shaft 43 formed integrally with the rotary transfer plate 41 on which the raw material is loaded by the rotating pedestal 45 and the locking protrusion 42 is rotated using the rotating means 44 to advance and retreat by the transfer table 47. A material transfer part 4 which loads the material on the upper portion of the transfer plate 48 and pushes the material to the push rod 47a formed on the transfer table 47 advancing by the fluid pressure cylinder 49; Lacquer reciprocating by the fluid pressure cylinder 53 by installing the swivel wheel 52 having the rotary gear 52a formed on the upper part of the movable bed 51 moving along the guide 51a by the fluid pressure cylinder 51b. The gear 53a and the rotary gear 52a are engaged to rotate the rotating table 52 to the left and right, and an arc-shaped forming groove 54 is formed at one side of the upper surface of the rotating table 52 to form a fluid pressure cylinder 53 thereon. A clamping plate 56 pressurized by), and on one side thereof, a fixing clamp 57 which is operated by the fluid pressure cylinder 56a to install and roll the rolled material to rotate. A blade forming roller (63) (63 ') is installed between the upper and lower guide plates (61) between the upper and lower guide plates (61) to contact the material along the arc-shaped moving line of the material attached to the rotary mounting (5). Gears 64, 64 'formed at each end of the rotating shaft are engaged with each other, but the gear 64 on one side is engaged with the rack gear 65a reciprocating with the fluid pressure cylinder 65, bending the material and cutting the blade. Banding rolling part 6 to be molded and A pair of robot arm feeders (71, 71 ') are installed, and the robot arm feeder (71) on one side picks up the material processed by the bending rolling section (6) and punches a mold (72) having an alignment cylinder (72a). And the other side robot arm feeder (71 ') is to turn the punching mold 72 to the inverted material into the drawing mold (73), and the press portion (7) for discharging the finished material Apparatus for manufacturing rotary blades for agricultural work equipment comprising a reheat treatment unit receiving the material discharged from the press unit 7 through the discharge conveyor 81 and heat-treating it to the heating furnace 21 again. The method according to claim 1, the material supply unit 1 is provided with a mounting table 18 on which a plurality of materials are loaded on one side and the upper side of the supply table 12 by forming a flat feed table 12 The input plate 14a connected to the rod of the injection cylinder 14 enters the discharge groove 25 formed at the lower end of the material stacking portion 13 formed in the front and pushes the stacked materials one by one in front of the pusher 15. Manufacturing apparatus for rotary blades for agricultural machinery