WO2005077144A1

WO2005077144A1 - A knife protect cover of weed cuter

Info

Publication number: WO2005077144A1
Application number: PCT/KR2005/000395
Authority: WO
Inventors: Jin Hyeok Jeong
Original assignee: Jin Hyeok Jeong
Priority date: 2004-02-13
Filing date: 2005-02-12
Publication date: 2005-08-25
Also published as: KR20050081398A; KR100545371B1

Abstract

Disclosed is a cover for protecting a blade of a grass cutter. Guide legs formed at regular intervals on both sides of an arc blade cover with an open bottom may keep the cutting surfaces at a height from the ground, so grass may be cut at the height. Grass is divided and introduced between the guide legs, so workers may cut grass easily. A net plate is installed upright at rear side of the upper surface of a blade protection cap to divide the cut grass, so workers may cut grass with checking the working state. The net plate controls movement of the cap when the grass cutter is swung laterally, so a worker may cut grass with moving the cap as desires. A wheel is installed at rear end of the blade protection cap, so cap may be moved laterally easier with being supported on the ground, with relieving fatigue of the worker and improving workability.

Description

Description A KNIFE PROTECT COVER OF WEED CUTER Technical Field

[1] The present invention relates to a cover for protecting a blade of a grass cutter, which is improved so that the cover is installed above a blade mounted at a front end of a motor box to protect the a blade and enhance safety of a worker.

[2] More particularly, the present invention relates to a cover for protecting a blade of a grass cutter, wherein guide legs are formed at regular intervals on an outer surface (or, an upper surface) of an arc blade cover with the open bottom to keep blades at a constant height from the ground so that a disk-type blade mounted inside a lower portion of a blade protection cap to rotate may cut grass introduced between the guide legs, wherein a net plate is installed upright at a rear side of an upper surface of the blade protection cap to divide the cut grass to right and left sides and control movement of the blade protection cap provided with blades so that a worker may move the blade protection cap as desires, and wherein a wheel is installed at a rear end of the blade protection cap so that the blade protection cap may be moved laterally easier, thereby improving workability. Background Art

[3] Generally, a blade mounted to a grass cutter has a disk shape as disclosed in Korean Utility Model Registration No. 277266, entitled "Disc blade for grass cutter" In the grass cutter, linear portions are formed at regular intervals on the outer circumference of a disk having a hole at its center, and an upper end of a linear portion in the front and a lower end of a linear portion in the rear are interconnected using a curved portion. A blade separately shaped is integrally combined to the linear portion by means of welding.

[4] However, the disk and the blade should be prepared separately. In addition, since the blade should be welded to the linear portion, much time is required for manufacture together with deteriorated productivity. Moreover, since the blade is formed only in one side, a cutting side becomes dull, the blade should be wasted, thereby deteriorating utilization of the blade.

[5] As for a cover for protecting a blade of a grass cutter, there are already known Korean Utility Model Registration No. 194264 "A safety cover for a blade of a grass cutter", Korean Utility Model Registration No. 238475 "A grass cutter with a safety function", Korean Utility Model Registration No. 257813 "A safety net for preventing danger of a grass cutter", Korean Utility Model Registration No. 292421 "A device for protecting a blade of a grass cutter", and Korean Utility Model Registration No. 335439 "A protection cap of a grass cutter and a grass cutter having the protection cap".

[6] Korean Utility Model Registration No. 194264 "A safety cover for a blade of a grass cutter" discloses that protrusions are formed out of a cutter on an outer circumference of a circular cover at regular intervals so that a cutter (or, a blade) may rotate below the circular cover and the protrusions.

[7] In this configuration, the protrusions protruded on the outer circumference of the circular cover divide grass during the grass cutting work, thereby facilitating the work to some extent. However, since a bottom surface of the circular cover is on the same horizontal plane as a lower bottom of the protrusion, the bottom of the circular cover is substantially contacted with the ground. Thus, the cutter is collided with the ground, thereby deteriorating the cutting efficiency and causing damage or breakdown of the cutting blade.

[8] Korean Utility Model Registration No. 238475 "A grass cutter with a safety function" discloses that a blade protection member is installed below a blade mounted to a rotary shaft of a transmission unit installed in a shaft cap, and guide protrusions and guide grooves are alternately formed on both sides of the blade protection member. The guide protrusions divide grass during the grass cutting work so that the divided grass is introduced into the guide grooves and then cut. However, the blade protection member has so small thickness to be substantially contacted with the ground, so small stones are apt to be easily moved above the blade protection member and then collided with a blade, resulting in damaging the blade due to the collision.

[9] Korean Utility Model Registration No. 257813 "A safety net for preventing danger of a grass cutter" discloses that a blade protection plate has a front plate and a rear plate that are integrally connected, and safety nets are installed on the bottom of the front plate at regular intervals so that a blade is installed in the safety net. During the grass cutting work, grass is divided and introduced into the safety nets installed at regular intervals, thereby facilitating more efficient cutting. However, since the safety nets should be kept at a suitable height from the ground, it is not possible to give a uniform height of the grass.

[10] Korean Utility Model Registration No. 292421 "A device for protecting a blade of a grass cutter" discloses a toothed safety plate is installed above a blade so as to be curved upward. The curved safety plate is kept at a certain height from the ground in a horizontal state, thereby capable of preventing collision between the blade and the ground. However, if an inclined angle of the safety plate is changed, the blade may be collided with the ground. In addition, since the safety plate has a blade in which teeth are formed around the center at regular intervals, grass may not be introduced into the toothed blade but deviated when the grass cutter is moved laterally. Thus, grass is not easily cut.

[11] Korean Utility Model Registration No. 335439 "A protection cap of a grass cutter and a grass cutter having the protection cap" discloses that a protection cap is installed above a blade. The protection cap is configured so that a wing is kept at a constant angle on an outer side of a mounting plate and a groove is formed inward at a lower end of the wing so that an outer circumference of the blade is moved in the groove. Thus, the wing may protect the blade. However, since the wing of the protection cap has teeth formed around the center at regular intervals, grass may not be introduced into the toothed wing but deviated when the grass cutter is moved laterally, so grass is not easily cut.

[12] In particular, such conventional blade protection caps (or, a safety net and a safety device) just have a plate shape just for protecting a blade, so cut grass is not discharged out of the cover (or, the plate) but accumulated thereon. Thus, in order to check a working state (or, procedure or degree of grass cutting), the grass cutter should be pulled back and then the grass accumulated on the circular cover should be removed. In addition, since there is no device (or, function) for controlling movement of the blade protection cap, the grass cutter may move freely regardless of intension of a worker, so the worker should grip the grass cutter firmly for the grass cutting work. Moreover, since there is provided no means for supporting movement on the bottom, the grass cutter is not supported on the ground when being swung laterally, and the worker should keep the grass cutter at a certain height, resulting in increasing fatigue of the worker and deteriorating work efficiency. Disclosure of Invention Technical Problem

[13] The present invention is designed to solve the problems of the prior art, and therefore the invention is directed to providing an improved cover for protecting a blade of a grass cutter.

[14] An object of the invention is to provide a cover for protecting a blade of a grass cutter in which guide legs are formed at regular intervals on both sides of an arc blade cover with an open bottom, a net plate is installed upright at the rear of an upper surface of the blade protection cap, and a wheel is installed at the rear end of the blade protection cap.

[15] Another object of the invention is to provide a cover for protecting a blade of a grass cutter in which guide legs installed at regular intervals on both sides of an arc blade cover with an open bottom keeps a blade at a certain height from the ground, and grass is divided and introduced between the guide legs to make the grass cutting work easier. [16] Still another object of the invention is to provide a cover for protecting a blade of a grass cutter in which a net plate is installed upright at the rear of an upper surface of a blade protection cap so as to divide cut grass to right and left portions so that a worker may cut grass with checking a working state (procedure and degree of grass cutting), and in which the net plate installed upright controls movement of the blade protection cap when the grass cutter is swung laterally so that the worker may cut grass with moving the blade protection cap as desires.

[17] Further another object of the invention is to provide a cover for protecting a blade of a grass cutter in which a wheel is installed at the rear end of a blade protection cap so that the blade protection cap may be moved laterally easier with being supported on the ground, together with relieving fatigue of the worker and improving workability.

[18] Still another object of the invention is to provide a cover for protecting a blade of a grass cutter in which a disk-type blade rotates with being hidden in a lower inner side, not exposed out of a blade protection cap, to ensure stability, and in which large stones pass above the blade protection cap and small stones pass below the disk-type blade so that they are not collided with the blade, resulting in significantly improving safety of the worker. Technical Solution

[19] In order to accomplish the above object, the present invention provides a cover for protecting a blade of a grass cutter, in which a disk-type blade is mounted to a rotary shaft of a transmission box mounted to a front end of a transmission protection pipe, and a blade protection cap for protecting the blade is provided above the disk-type blade,

[20] wherein the disk-type blade mounted to the rotary shaft of the transmission box includes a disk and a plurality of blades formed at regular intervals on an outer circumference of the disk, and cutting surfaces are formed in parallel on both sides of the blades so as to be inclined,

[21] wherein the blade protection cap installed above the disk-type blade includes guide legs integrally formed at regular intervals so that front ends of the guide legs configure a circle, and each of the guide legs is configured so that a support protrusion is protruded downward at a front end of a support member at both sides of a centerline on an upper surface of an arc blade cover having a shaft hole at a center,

[22] wherein a net plate is integrally formed on an upper surface of the blade protection cap, and

[23] wherein a wheel is installed at a rear end of the upper surface of the blade protection cap so as to keep a right angle to the centerline, and an outer circumference of the wheel is protruded downward below a bottom of rear guide legs. [24] Preferably, one or more net plate is integrally formed on the upper surface of the blade protection cap.

[25] Also preferably, the wheel is installed at the rear end of the upper surface of the blade protection cap so as to keep a right angle to the centerline, a wheel mount with a pinhole formed in a lateral direction is integrally formed to the net plate, a wheel shaft is buried in the wheel mount so that a pin is combined to fix the wheel shaft in the pinhole, and the wheel is rotatably installed at a front end of the wheel shaft.

[26] Also preferably, the guide legs are installed at regular intervals on both sides of the centerline on the upper surface of the arc blade cover, and the support protrusions of the guide legs positioned at a center portion of both sides are protruded downward below the support protrusions of the other guide legs positioned at outer portions. Brief Description of the Drawings

[27] Fig. 1 is an exploded perspective view showing a cover for protecting a blade of a grass cutter according to the present invention.

[28] Figs. 2 to 4 are plane, front and side views showing a blade protection unit of the cover for protecting a blade of a grass cutter according to the present invention.

[29] Fig. 5 is a sectional view showing a cover for protecting a blade of a grass cutter according to another embodiment of the present invention, which is mounted to a grass cutter. Best Mode for Carrying Out the Invention

[30] Fig. 1 is an exploded perspective view showing a cover 1 for protecting a blade of a grass cutter according to the present invention, Figs. 2 to 4 are plane, front and side views showing a blade protection cap 2 of the cover 1 for protecting a blade of a grass cutter according to the present invention, and Fig. 5 is a sectional view showing a cover 1 for protecting a blade of a grass cutter according to another embodiment of the present invention, which is mounted to a grass cutter.

[31] The cover 1 for protecting a blade of a grass cutter according to the present invention includes a blade protection cap 2 and a disk-type blade 20.

[32] The blade protection cap 2 is installed above the disk-type blade 20 and has an arc blade cover 3 with a curved (or, arc) shape. The arc blade cover 3 has a shaft hole 4 at its center so that a transmission box 16 may be installed therein. A central support member 9 is formed at a center of the upper surface of the arc blade cover 3, and guide legs 5 and 5-1 are formed on both sides of the arc blade cover 3 at regular intervals.

[33] In particular, the guide legs 5 and 5-1 are configured so that a support protrusion 7 is protruded downward at the front end of a support 6. The support protrusions 7 provided to the guide legs 5-1 that are positioned in the center portion among the guide legs 5 and 5-1 have bigger size so as to be protruded further than other support protrusions 7 of the guide legs 5 that are positioned in the outer portion, so that the blade protection cap 2 may protect the guide legs 5 and play an essential role for stable guiding when a worker cuts grass.

[34] A net plate 10 is formed on the upper surface of the blade protection cap 2 only in the rear portion as shown in Figs. 1 to 4 to conform to the central support member 9, or formed in plural in the front and rear portions as shown in Fig. 5 with the same or larger size. A pinhole 12 is formed at the lower end of the rear surface of the net plate 10. A wheel mount 11 with a cylindrical or thick shape is integrally formed in the pinhole 11 so that a wheel 13 is installed to keep a right angle to a centerline. A wheel axis 14 is buried in the wheel mount 11, and the wheel 13 is mounted to the wheel axis 14 exposed out of the wheel mount 11 so that its outer circumference is protruded downward lower than the bottom of rear guide legs 5-2. A pin 52 is inserted into the wheel axis 14 through the pinhole 12 so that the wheel axis 14 is not separated.

[35] The disk-type blade 20 is mounted below the blade protection cap 2 to a rotary shaft of the transmission box 16. The disk-type blade 20 includes a disk 21 and a plurality of blades 23 formed on the outer circumference of the disk 21 at regular intervals. On both sides of the blades 23, cutting surfaces 24 are formed side by side to be inclined to the same direction.

[36] Now, operation of the cover for protecting a blade of a grass cutter according to the present invention is described.

[37] The cover 1 for protecting a blade of a grass cutter according to the present invention is fixed to the transmission box 16 mounted to the front end of a protection pipe 17 provided with a handle (not shown in detail) at the shaft hole 4 formed at the center of the blade protection cap 2. The net plate 10 integrally formed to the blade protection cap 2 is mounted to be positioned below the transmission protection pipe 17. The disk-type blade 20 is mounted to the rotary shaft of the transmission box 16 below the blade protection cap 2 through a mount hole 22. If the disk-type blade 20 is mounted below the blade protection cap 2, the blades 23 of the disk-type blade 20 are positioned in the support protrusion 7 protruded downward at the front ends of the guide legs 5 and 5-1.

[38] In the state that the blade protection cap 2 and the disk-type blade 20 are installed to the transmission box 16, a user may use the grass cutter in a conventional way.

[39] If a user manipulates a switch (not shown) of the grass cutter, power generated in a power unit (not shown) is transmitted to the transmission box 16 through the transmission axis installed in the transmission protection pipe 17. Then, the rotary shaft (not shown) is rotated by means of the transmission device (not shown) installed in the transmission box 16 so as to rotate the disk-type blade 20.

[40] While the disk-type blade 20 is rotating, a user moves the transmission protection pipe 17 right and left repeatedly with the blade protection cap 2 being seated in a grass field. Then, the guide legs 5 and 5-1 are moved into a cluster of bush to divide the grass by some amounts. The divided grass is then cut by the blades 23 of the rotating disk-type blade 20. At this time, since the grass introduced between the guide legs 5 and 5-1 keep seized therein, the grass may be easily cut using a relatively smaller force. The cut grass is fallen over the blade protection cap 2, and the grass scattered over the blade protection cap 2 is moved right or left along the blade protection cap 2 that moves right and left.

[41] Among the grass cut and scattered by the blades 23, grass flying rearward is swept right or left by means of the net plate 10 installed in the front and rear of the upper portion of the blade protection cap 2. Thus, the upper surface of the blade protection cap 2 and the main surface for movement of the blade protection cap 2 are always kept clean, so the work may cut grass with checking the state of cut grass, thereby ensuring safe cutting work.

[42] In particular, when the blade protection cap 2 is moved right and left repeatedly on the grass field together with the transmission protection pipe 17, the support protrusions 7 of the guide legs 5-1 positioned at the center portion of the right and left sides are contacted with the ground prior to the support protrusions 7 of the other guide legs 5 so that the guide legs 5 are positioned above the ground. In addition, the wheel 13 installed at the rear of the net plate 10 is rotated in contact with the ground. Thus, a contact (or, resistance) with the ground is decreased, so the blade protection cap 2 may be moved more easily. In addition, small stones passing below the guide legs 5 and the blade protection cap 2 are moved below the disk-type blade 20 without collision, preventing the blades 23 of the disk-type blade 20 from being damaged. Though a stone is introduced into the blade protection cap 2, the stone generally having a circular or oval shape is just contacted with the disk 21 of the disk-type blade 20, not colliding with the blades 23 around the disk 21, so the blades 23 are not damaged.

[43] In addition, since the wheel 13 installed at the rear is rolled on the ground, the grass cutter may be moved right and left more easily. In addition, the rolling wheel 13 supports the transmission box 16 and the transmission protection pipe 17, so a worker may cut the grass without exerting great force.

[44] Moreover, since the disk-type blade 20 has the cutting surfaces 24 formed on both sides (or, the front and rear sides) of the blades 23 in the same direction in parallel, if the cutting surfaces 24 on one side are worn, the disk-type blade 20 is turned over and then mounted so that the cutting surfaces 24 on the other surface may be used. Thus, the disk-type blade 20 of the present invention may be used for a long time over twice rather than a conventional one.

[45] In particular, the cover 1 for protecting a blade of a grass cutter according to the present invention is configured so that the blade protection cap 2 is not exposed out but rotated with being hidden inside the lower portion, thereby keeping stable. In addition, though the blades 23 pass over large and small stones, the stones are not collided with the blades, so a worker may cut grass as desires without any danger, thereby greatly improving working efficiency.

[46] Though specific embodiments are described in the present invention, it would be apparent to those skilled in the art that there may be various changes and modifications within the sprit of the invention, and such changes and modifications are also included in the scope of the appended claims. Industrial Applicability

[47] The present invention relates to a cover for protecting a blade of a grass cutter, wherein the guide legs are formed on both sides of the arc blade cover with an open bottom at regular intervals, the net plate is installed upright at the rear of the upper surface of the blade protection cap, and the wheel is installed at the rear end of the blade protection cap. The guide legs formed at regular intervals on both sides of the arc blade cover with the open bottom may keep the cutting surfaces at a constant height from the ground so that grass may be cut at a constant height. In addition, since grass is divided and introduced between the guide legs, a worker may cut grass more easily. Moreover, since the net plate is installed upright at the rear side of the upper surface of the blade protection cap to divide the cut grass to right and left sides, a worker may cut grass with checking the working state (or, procedure and degree of grass cutting). In addition, since the net plate installed upright controls movement of the blade protection cap when the grass cutter is swung laterally, the worker may cut grass with moving the blade protection cap as desires. Furthermore, since the wheel is installed at the rear end of the blade protection cap, the blade protection cap may be moved laterally easier with being supported on the ground, together with relieving fatigue of the worker and improving workability. In addition, since the disk-type blade rotates with being hidden in a lower inner side, not exposed out of a blade protection cap, stability is ensured. Moreover, since large stones pass above the blade protection cap and small stones pass below the disk-type blade when the blade protection cap is moving, the stones are not collided with the blade, resulting in significantly improving safety of the worker.

Claims

[1] A cover for protecting a blade of a grass cutter, in which a disk-type blade (20) is mounted to a rotary shaft of a transmission box (16) mounted to a front end of a transmission protection pipe (17), and a blade protection cap (2) for protecting the blade is provided above the disk-type blade (20), wherein the disk-type blade (20) mounted to the rotary shaft of the transmission box (16) includes a disk (21) and a plurality of blades (23) formed at regular intervals on an outer circumference of the disk (21), and cutting surfaces (24) are formed in parallel on both sides of the blades (23) so as to be inclined, wherein the blade protection cap (2) installed above the disk-type blade (20) includes guide legs (5)(5-l) integrally formed at regular intervals so that front ends of the guide legs (5)(5-l) configure a circle, and each of the guide legs (5)(5-l) is configured so that a support protrusion (7) is protruded downward at a front end of a support member at both sides of a centerline on an upper surface of an arc blade cover (3) having a shaft hole (4) at a center, wherein a net plate (10) is integrally formed on an upper surface of the blade protection cap (2), and wherein a wheel (13) is installed at a rear end of the upper surface of the blade protection cap (2) so as to keep a right angle to the centerline, and an outer circumference of the wheel (13) is protruded downward below a bottom of rear guide legs (5-2).

[2] The cover for protecting a blade of a grass cutter according to claim 1, wherein one or more net plate (10) is integrally formed on the upper surface of the blade protection cap (2).

[3] The cover for protecting a blade of a grass cutter according to claim 1, wherein the wheel (13) is installed at the rear end of the upper surface of the blade protection cap (2) so as to keep a right angle to the centerline, a wheel mount (11) with a pinhole (12) formed in a lateral direction is integrally formed to the net plate (10), a wheel shaft (14) is buried in the wheel mount (11) so that a pin (15) is combined to fix the wheel shaft (14) in the pinhole (12), and the wheel (13) is rotatably installed at a front end of the wheel shaft (14).

[4] The cover for protecting a blade of a grass cutter according to claim 1, wherein the guide legs (5)(5-l) are installed at regular intervals on both sides of the centerline on the upper surface of the arc blade cover (3), and the support protrusions (7) of the guide legs (5) positioned at a center portion of both sides are protruded downward below the support protrusions (7) of the other guide legs (5) positioned at outer portions.