JP2004236558A - Tilling shaft sealing structure for rotary tilling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tilling shaft sealing structure for a rotary tilling device, with which a female conical part is formed as a barrier against progress of weeds gradually shrinking in diameter toward a supporting case, weeds and soil coiled with weeds are hardly penetrated into an oil seal, the durability of a sealing member is improved and discharge of weeds and soil reached to the outside of the female conical part by a rotating spiral groove is promoted. <P>SOLUTION: The sealing cover means 12b of the tilling shaft sealing structure is constituted of a rotary cover member 101 attached to a tilling cylinder 72 and a stationary cover member 102 attached to a supporting case 12a. The rotary cover member 101 has the female conical part increasing in diameter toward the supporting case 12a. The stationary cover member 102 has a male conical part enclosing the female conical part 105 and forms the spiral groove on the outside of the female conical part. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a tilling shaft seal structure of a rotary tilling device provided in a tilling machine.
[0002]
[Prior art]
A conventional tiller shaft seal structure of a tiller has a structure in which a cover that prevents foreign matter from entering an oil seal fitted to a tiller shaft is disposed in front of the oil seal (for example, see Patent Document 1).
[0003]
[Patent Document 1]
Japanese Utility Model Laid-Open No. 57-102902 (page 3-4, FIG. 2)
[0004]
Patent Document 1 will be described in detail with reference to the drawings.
FIG. 8 is an explanatory view of a structure of a tiller shaft support of a conventional rotary tillage device (a photograph of FIG. 2 of Patent Document 1).
In the conventional tilling claw shaft support structure, the tilling claw shaft 4 is attached to the support member 2 (the reference numeral used in the gazette is the same as that described in the above-mentioned gazette; the same applies hereinafter) via the ball bearing 9 and the seal member 5. By disposing the cover 1 attached to the tilling claw shaft 4 inside the cylindrical portion end surface 12 of the cylindrical portion 2 a of the member 2, it was possible to prevent the swarf dust and the like from wrapping around the cover 1.
[0005]
[Problems to be solved by the invention]
In the structure of FIG. 8 described above, although it is difficult for the scraps and the like to wind around the end surface 11 of the cover 1, when the straw and grass reach the outer cylindrical portion 1a of the cover 1, the movement on the outer cylindrical portion 1a is easy, It is easy to invade, and the frequency of removing straws and grass increases, which takes time.
[0006]
Therefore, an object of the present invention is to reduce the intrusion of grass and soil toward a seal member provided between a support case and a tillage shaft, and to improve the durability of the seal member by using a tillage shaft of a rotary tillage device. It is to provide a seal structure.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention provides a support case in which a cultivating shaft is rotatably supported via a bearing, and a seal member for preventing foreign substances heading for the bearing is provided outside the bearing with the cultivating shaft and the supporting case. A tilling shaft seal structure of a rotary tilling device, wherein a seal cover means for reducing foreign substances directed toward the sealing member is interposed between the cultivating shaft and the support case outside the sealing member. The cover means includes a rotating cover member attached to the tillage shaft, and a fixed cover member attached to the support case. The rotating cover member has a female conical portion that expands in diameter toward the support case. And a male conical portion surrounding the female conical portion.
[0008]
The female cone that expands in diameter toward the support case serves as a barrier for the progress of grass that gradually decreases in diameter toward the support case, and foreign matter such as grass and soil wrapped with grass is less likely to enter. Therefore, it is possible to prevent grass and soil from entering the seal member and improve the durability of the seal member.
[0009]
In claim 2, when the tilling shaft is turned for tilling work, the male groove corresponding to the female cone portion is formed on the outer surface of the female cone portion with a spiral groove that advances from the enlarged diameter side to the reduced diameter side. I do.
[0010]
When tilling work, the female cone rotates and the spiral groove rotates at the same time. As a result, it is possible to encourage the grass and soil reaching the outer surface of the female cone portion to be discharged by the rotating spiral groove. Therefore, the durability of the sealing member can be further improved.
[0011]
According to a third aspect of the present invention, the spiral groove has a peak formed at an acute angle.
The sharp mountain top can cut the grass that wraps around the female cone, and the sharp mountain top can facilitate the discharge of grass and soil that has reached the female cone, and wrap the grass. Suppress.
[0012]
According to a fourth aspect, an interval between the female cone portion and the male cone portion is narrowed in a direction away from the seal member.
The grass returned toward the direction away from the seal member by the rotation of the spiral groove formed on the outer surface of the female conical portion is subjected to a compressive action in a narrow place and further cut. As a result, winding of grass is further suppressed, and invasion of grass is suppressed.
[0013]
According to a fifth aspect of the present invention, the female conical portion has an edge formed by an outer surface and an end surface formed at an acute angle.
The cutting edge is formed by forming the edge portion into an acute angle. A sharp edge can cut grass more reliably. That is, grass that could not be cut at the top of the mountain can be cut at the final end face, further suppressing winding of grass and suppressing grass invasion.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of reference numerals.
FIG. 1 is a perspective view of a walking rotary tiller employing a tillage shaft seal structure according to the present invention. “Left”, “right”, “upper”, and “lower” in the upper right of the figure indicate directions viewed from the operator, “front” indicates the forward side, and “rear” indicates the opposite side.
[0015]
The walking rotary tiller 10 (hereinafter simply referred to as “tiller 10”) includes left and right traveling wheels 13 and 14 (see FIG. 3) from an engine 11 as a drive source via a power transmission device 12 and these components. There is a structure in which power is transmitted to left and right rotary tillage devices 15 and 16 disposed in front of the traveling wheels 13 and 14, and a working device such as a ridge device 17 (see FIG. 2) is connected to a rear portion of the power transmission device 12. For example, the ridges are erected by the ridger 17 while cultivating the field with the rotary tilling devices 15 and 16.
[0016]
FIG. 2 is a side view of the cultivator according to the present invention. The cultivator 10 further includes an engine 11 disposed on an upper part of the body and a clutch (clutch case 11a) not shown in the lower part of the engine 11. Power transmission device 12, rotary tilling devices 15 and 16 rotatably mounted at the front of the power transmission device 12, and left and right axles 13 a and 14 a at the rear of the power transmission device 12 (see FIG. 3). The driving wheels 13 and 14 are rotatably mounted via the power transmission device 12, the handle 18 extends rearward and obliquely upward from the rear of the power transmission device 12, and a coupling mechanism 21 is mounted at the rear end of the power transmission device 12. G indicates a running surface.
[0017]
Here, 31 is a traveling auxiliary wheel mounted on the front end of the power transmission device 12 so as to be vertically adjustable, 32 is a fender that covers the power transmission device 12 and the rotary tilling devices 15 and 16, and 33 is an upper portion of the engine 11. , An air cleaner, 34 is an air cleaner cap, 35 is a fuel tank filler cap, 36 is a shift lever, 37 is a differential lock lever, 38 is a clutch lever, and 41 is a spring for flipping up a working device connected to the connecting mechanism 21. The raising lever 42 is a sinking position adjusting lever for adjusting the sinking position of the working device connected to the connecting mechanism 21.
[0018]
FIG. 3 is a plan view of the cultivator according to the present invention. The cultivator 10 includes a recoil starter knob 51 for starting the engine 11 and a throttle lever 52 for adjusting the output of the engine 11 at the front right side of the handle 18. The above-mentioned differential lock lever 37 is arranged, an engine switch 53 for stopping the engine 11 is mounted on the left rear portion of the handle 18, a clutch lever 38 is mounted on the rear portion of the handle 18, and the power transmission device 12 (see FIG. 1) is mounted. This shows that the transmission lever 36 is extended rearward from the center of the rear part, and the lever 41 is lifted up from the rear left part of the coupling mechanism 21 to the rear.
[0019]
FIG. 4 is a sectional view taken along line 4-4 of FIG. 2, and shows the rotary tilling device 15 and the power transmission device 12.
The power transmission device 12 includes a support case 12a and an intermediate transmission means 62 (first and second chain gears 63 and 64, first gears 65 and 65, a second gear 65) driven via a first chain 61 in the support case 12a. A chain 66).
[0020]
The rotary tillage device 15 includes a first tillage shaft 71 that is rotated by the power transmission device 12, and a tillage shaft that rotates by the power transmission device 12 and is rotatably fitted between the support case 12 a and the first tillage shaft 71. A cultivating cylinder 72 serving as a second cultivating axis, a seal cover means 12b having a cultivating axis seal structure provided between the cultivating cylinder 72 and the support case 12a, and a shaft provided between the first cultivating axis 71 and the cultivating cylinder 72. It comprises a seal structure 73, an inner tilling claw 74 attached to the cultivation cylinder 72, and an outer tilling claw 75 attached to the first cultivation shaft 71.
[0021]
The cultivation cylinder 72 is a hollow shaft as a cultivation shaft attached to the support case 12a via a bearing 72a. Specifically, the outer cylinder 77 is fixed to the inner cylinder 76 with bolts 78, and the inner tilling claw 74 is rotated via the second gear 81 provided on the inner cylinder 76 in the rotation direction of the traveling wheel 13 (see FIG. 1). a (see FIG. 1) in the same rotational direction b (see FIG. 1). Reference numeral 72b denotes a seal member interposed between the cultivating cylinder (tilling shaft) 72 and the support case 12a outside the bearing 72a (in the direction of the arrow (1)).
[0022]
The first cultivation shaft 71 has a substantially symmetrical shape about a central symmetric center line 87 and is included in the rotary tilling device 16.
The rotary tilling device 16 is substantially the same as the rotary tilling device 15, and the description of the rotary tilling device 16 is omitted.
[0023]
The seal cover means 12b of the cultivation shaft seal structure is characterized by comprising a rotating cover member 101 attached to the cultivation cylinder 72 and a fixed cover member 102 attached to the support case 12a. Next, the details will be described.
[0024]
FIG. 5 is a detailed view of part 5 of FIG. 4, and shows the rotating cover member 101 and the fixed cover member 102 of the seal cover means 12b.
The rotating cover member 101 has a disk portion 104 attached to the end of the cultivation cylinder 72 by welding, and a female cone portion extending from the disk portion 104 toward the support case 12a (in the direction of arrow {circle around (2))). 105.
[0025]
The female conical portion 105 has an enlarged diameter portion 107 and a reduced diameter portion 108, and the diameter of the enlarged diameter portion 107 is set to Da, the diameter of the reduced diameter portion 108 is set to Ds, and the central angle of the female conical portion 105 is set to θ. It was done.
[0026]
The fixed cover member 102 includes an attachment portion 111 attached to the support case 12a, and a male cone portion 112 surrounding the female cone portion 105 of the rotating cover member 101 formed continuously from the attachment portion 111.
[0027]
The space between the female conical portion 105 and the male conical portion 112 is reduced in the direction away from the seal member 72b (the direction of the arrow (1)). Specifically, the size of the gap between the enlarged diameter portion 107 of the female conical portion 105 and the male conical portion 112 is Sa, and the size of the gap between the reduced diameter portion 108 of the female conical portion 105 and the male conical portion 112. Is defined as Ss (Ss <Sa).
[0028]
FIG. 6 is a front view of the rotating cover member according to the present invention, showing the female cone portion 105 of the rotating cover member 101.
The female conical portion 105 also has a spiral groove 116 formed on the outer surface 114.
When the cultivation cylinder (tilling shaft) 72 is turned for cultivation work, the spiral groove 116 reduces foreign matter such as grass and soil on the male side corresponding to the female cone portion 105 from the enlarged diameter portion 107 side. It is a spiral that advances toward the diameter portion 108 (in the direction of arrow (1)). For example, when the inner tilling claw 74 of the tilling machine 10 shown in FIG. 1 on the rotary tilling device 15 side is turned in the rotation direction b, the foreign matter advances in the left direction of the arrow. On the other hand, on the rotary tilling apparatus 16 side, the foreign matter advances in the right direction of the arrow.
[0029]
The spiral groove 116 is a groove in which the peak 117 is formed at an acute angle θm. The angle θm is set to, for example, 60 °.
The specifications of the spiral groove, such as the number of peaks and the diameter of the valley of the spiral groove 116, are arbitrary.
[0030]
The operation of the above-described rotary tilling shaft seal structure of the rotary tilling apparatus will be described below.
When the tilling operation is performed by the cultivator 10 of FIG. 1, foreign matter such as soil is entangled with the grass along with the rotation of the rotary tilling devices 15 and 16 with the rotary tilling devices 15 and 16. The cover member 102 is provided to prevent grass and soil from entering between the support case 12a and the cultivation cylinder 72. Specifically, grass or soil entangled with the rotating cover member 101 starts to advance on the female conical portion 105 of the rotating cover member 101 in the axial direction (the direction of arrow {circle around (2)}) and gradually tightens (the diameter becomes smaller). Therefore, when the female cone portion 105 is formed on the rotating cover member 101, the movement resistance of the grass that is tightened while approaching the seal member 72b by the cone gradually increases, and grass and soil are less likely to enter.
[0031]
As described above, in the seal cover means 12b having the tillage shaft seal structure, the rotating cover member 101 has the female cone portion 105 whose diameter increases toward the support case 12a, and the fixed cover member 102 surrounds the female cone portion 105. Since the female cone 105 has the male conical portion 112, the female conical portion 105 expanding in diameter toward the support case 12a serves as a barrier for the progress of grass that gradually decreases in diameter toward the support case 12a, and grass and soil wrapped with the grass enter. It becomes difficult. Therefore, grass and soil can be suppressed from entering the seal member 72b, and the durability of the seal member 72b can be improved.
[0032]
When grass or soil reaches the female cone portion 105 of the rotating cover member 101 of the seal cover means 12b shown in FIG. 6, the grass or soil is intruded by the rotation of the spiral groove 116 of the female cone portion 105 (rotation direction b). Upon receiving the component force Fg pushed in the opposite direction, the force is sent outward as shown by arrows (5) and (5).
[0033]
Thus, in the seal cover means 12b of the cultivation shaft seal structure, when the cultivation shaft (the cultivation cylinder 72) is turned for cultivation work, the male side (grass or soil) corresponding to the female cone portion 105 expands in diameter. Since the spiral groove 116 that advances from the side to the reduced diameter side is formed on the outer surface 114 of the female conical part 105, the grass and soil reaching the female conical part 105 by the rotating spiral groove 116 are discharged by arrows (5) and (5). Can be prompted as follows. Therefore, the durability of the seal member 72b can be further improved.
[0034]
Since the spiral groove 116 has the peak 117 formed at an acute angle (for example, 60 °), the grass that is wound around the female conical portion 105 and is fastened can be cut by the acute peak 117. As a result, it is possible to facilitate the discharge of grass and soil reaching the female conical portion 105 and to suppress the winding of grass.
[0035]
As shown in FIG. 5, in the seal cover means 12b of the tilling shaft seal structure, the interval between the female cone portion 105 and the male cone portion 112 is narrowed in a direction away from the seal member 72b. The grass returned in the direction away from the seal member 72b (in the direction of arrow {circle around (1)}) (see FIG. 6) is compressed at the narrowed portion 108 and further cut. As a result, the winding of grass can be further suppressed and the invasion of grass can be suppressed.
[0036]
Next, another embodiment of the tillage shaft seal structure according to the present invention will be described.
FIG. 7 is a diagram showing another embodiment of FIG. 6, and the same components as those of the embodiment shown in FIG. 4 to FIG.
The female cone 105B has an edge 122 formed by the outer surface 114 and the end surface 121 at an acute angle θe. The angle θe is, for example, 60 °.
[0037]
By forming the edge 122 at an acute angle, the entire periphery of the edge 122 is used as a cutting edge. When the sharp edge portion 122 is formed on the entire circumference, grass can be cut more reliably. That is, the grass that could not be cut at the peak 117 can be cut at the final end face 121, so that the winding of the grass can be further suppressed and the invasion of the grass can be suppressed.
[0038]
Note that a spiral groove similar to the spiral groove shown in the embodiment of the present invention can be formed on the outer surface of the disk portion 104 of the rotating cover member 101. Specifically, a spiral groove for guiding foreign matter toward the center of the disk portion 104 by the rotation of the rotating cover member 101 in FIG. 5 is formed. As a result, it is possible to prevent the foreign matter adhering to the outer surface of the disk portion 104 of the rotating cover member 101 from advancing.
Although the fixed cover member is configured to be attached to the support case, it is also possible to form substantially the same male conical portion 112 integrally with the support case.
[0039]
【The invention's effect】
The present invention has the following effects by the above configuration.
In the first aspect, the seal cover means includes a rotating cover member attached to the tilling shaft and a fixed cover member attached to the supporting case, and the rotating cover member has a female conical portion whose diameter increases toward the supporting case. Since the fixed cover member has a male cone surrounding the female cone, the female cone that expands toward the support case becomes a barrier to the progress of grass that gradually decreases in diameter toward the support case, Soil wrapped with grass is less likely to invade. Therefore, grass and soil can be prevented from entering the seal member, and the durability of the seal member can be improved.
[0040]
According to claim 2, when the tilling shaft is turned for tilling work, the male side corresponding to the female conical portion is formed on the outer surface of the female conical portion with a spiral groove that advances from the enlarged diameter side to the reduced diameter side. The spiral groove can promote the discharge of grass and soil reaching the outer surface of the female cone. Therefore, the durability of the seal member can be further improved.
[0041]
According to the third aspect of the present invention, since the spiral groove has a peak formed at an acute angle, it is possible to cut grass that is wound around the female cone and tightened by the acute peak. As a result, it is possible to smoothly discharge grass and soil reaching the female conical portion, and it is possible to suppress winding of grass.
[0042]
According to the fourth aspect, the distance between the female conical portion and the male conical portion is reduced in the direction away from the seal member, so that the grass returned in the direction away from the seal member by the spiral groove is narrow. Under the action of compression, it is further cut. As a result, winding of grass can be further suppressed, and invasion of grass can be suppressed.
[0043]
According to the fifth aspect, the female conical portion has a shape in which an edge formed between the outer surface and the end surface is formed at an acute angle, and thus the edge is a cutting edge. A sharp edge can cut grass more reliably. That is, grass that could not be cut at the top of the mountain can be cut at the final end face, so that winding of grass can be further suppressed and grass invasion can be suppressed.
[Brief description of the drawings]
FIG. 1 is a perspective view of a walking rotary tiller employing a tillage shaft seal structure according to the present invention. FIG. 2 is a side view of a tiller according to the present invention. FIG. 3 is a plan view of a tiller according to the present invention. 4 is a sectional view taken along line 4-4 of FIG. 2 FIG. 5 is a detailed view of a part 5 of FIG. 4 FIG. 6 is a front view of a rotating cover member according to the present invention FIG. 7 is another embodiment of FIG. FIG. 8 is an explanatory view of the structure of a tiller shaft supporting portion of a conventional rotary tillage device [Description of reference numerals]
DESCRIPTION OF SYMBOLS 10 ... Walking rotary tiller, 12a ... Support case, 12b ... Seal cover means, 15 ... Left rotary tiller, 16 ... Right rotary tiller, 72 ... Tiller shaft (tilling cylinder), 72a ... Bearing, 72b ... Seal member, 101: rotating cover member, 102: fixed cover member, 105: female cone portion, 112: male cone portion, 114: outer surface of the female cone portion, 116: spiral groove, 117: mountain top portion, 121: female cone portion 122, an edge portion, Da: the diameter of the enlarged diameter portion, Ds: the diameter of the reduced diameter portion, θe: the angle of the edge portion, θm: the angle of the peak portion.

Claims (5)

The support case is rotatably supported by the tilling shaft via a bearing, and a seal member for preventing foreign matter toward the bearing is interposed between the cultivation shaft and the support case outside the bearing, and the foreign matter toward the seal member. A cultivating shaft seal structure of a rotary tilling device, wherein a seal cover means for reducing the outside of the sealing member is interposed between a cultivating shaft and a support case,
The seal cover means includes a rotating cover member attached to a tilling shaft, and a fixed cover member attached to a support case,
The rotary cover member has a female cone portion that expands in diameter toward a support case, and the fixed cover member has a male cone portion surrounding the female cone portion. Construction. A helical groove, in which the male side corresponding to the female cone portion advances from the enlarged diameter side to the reduced diameter side, is formed on the outer surface of the female cone portion when the tilling shaft is turned for tilling work. A tillage shaft seal structure of the rotary tillage device according to 1. The tilling shaft seal structure for a rotary tilling device according to claim 2, wherein the helical groove has a peak formed at an acute angle. The tilling shaft seal structure for a rotary tilling device according to claim 2, wherein an interval between the female conical portion and the male conical portion is narrowed in a direction away from the seal member. The tilling shaft seal structure for a rotary tilling device according to claim 2, wherein the female conical portion has an edge formed by an outer surface and an end surface formed at an acute angle.

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