JP2531397Y2 - Cutting blade shaft lock device of brush cutter - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting blade shaft lock device of a brush cutter for locking the rotation of a cutting blade shaft when a disk-shaped cutting blade is attached to or detached from a cutting blade shaft.

[0002]

2. Description of the Related Art Conventionally, in a brush cutter in which a disk-shaped cutting blade is detachably connected to a cutting blade shaft which is rotationally driven by a driving unit such as an engine or an electric motor, the cutting blade is frequently worn and frequently worn. We are replacing the cutting blade. Here, when replacing the cutting blade, it is necessary to lock the cutting blade shaft so as not to rotate. A conventional example of a cutting blade shaft locking device of a brush cutter will be described with reference to FIGS.

[0003] First, a case 3 is connected to one end of a pipe 2 housing and holding a transmission shaft 1 for transmitting power from an engine (not shown). The cutting blade shaft 6 is rotatably held via the. A bevel gear 7 is press-fitted and fixed to the upper part of the cutting blade shaft 6, and the bevel gear 7 meshes with a bevel gear 8 that is spline-fitted to the tip of the transmission shaft 1. Also,
The lower end of the cutting blade shaft 6 is formed so as to extend outside the case 3, and a spline groove 9 is formed in the outer peripheral portion of the lower end of the cutting blade shaft 6. Is formed with a female screw 10.

Next, a cutting blade holder 11 and a cutting blade holder 12 are spline-fitted to the outer periphery of the cutting blade shaft 6, and these cutting blade holder 11 and cutting blade holder 12 are connected to the female screw. It is fastened and fixed by a bolt 13 screwed into the connector 10. Further, on the outer periphery of the cutting blade holder 11, a dish-shaped dust slinger 14 for preventing soil and grass from entering the case 3 and a disc-shaped cutting blade 15 for cutting grass and the like are provided. Are fitted, and these dust slinger 1
The cutting blade 4 and the cutting blade 15 are clamped and fixed by the cutting blade holder 11 and the cutting blade holder 12 by tightening the bolt 13. The cutting blade holder 11 is formed with two engaging recesses 16 with which lock pins, which will be described later, are removably engaged.

A lock pin 17 having an axis parallel to the cutting blade shaft 6 is mounted on the case 3. The lock pin 17 has a lock position at which a lower end of the lock pin 17 is engaged with the engagement recess 16, and a lock position. The lock pin 17 is provided so as to be slidable and rotatable up and down to a lock release position for releasing the engagement state with the engagement recess 16. A spring 18 for urging toward a lock position to be engaged with the spring 18 is mounted.
A lever portion 19 bent at a substantially right angle is formed at an upper end portion of the lock pin 17, and a U-shaped groove portion 20 for engaging and holding the lever portion 19 is formed at an upper end portion of the case 3. Is formed.

In such a configuration, when replacing the cutting blade 15, the lock pin 17 is rotated to the position shown by the two-dot chain line in FIG. Then, as shown in FIG.
The lock pin 17 slides to the lock position due to the urging force, and the lower end of the lock pin 17 engages with the engagement concave portion 16, whereby the cutting blade shaft 6 is locked. For this reason, the bolt 13 can be turned by the blade replacement tool, and the blade 15 can be replaced.

On the other hand, during the cutting operation after the replacement of the cutting blade 15 has been completed, as shown in FIG.
By sliding the lock pin 1 to the unlock position.
The engagement state between the lower end of the lock 7 and the engagement recess 16 is released. Further, as shown by the solid line in FIG.
By rotating the lever 19 by 0 °, the lever 19 is
Is engaged and held. As described above, by sliding the lock pin 17 to the unlock position, the cutting blade shaft 6 becomes rotatable, and the cutting blade 15 is rotated and driven together with the cutting blade shaft 6 by the driving force from the engine. Is performed. Further, since the lever 19 of the lock pin 17 is engaged and held in the U-shaped groove 20, the lock pin 17 is maintained in a state of sliding to the unlocked position.

Here, since the lock pin 17 is attached to the case 3, it is possible to quickly lock the cutting blade shaft 6 when replacing the cutting blade 15, and to lock the cutting blade shaft 6. There is no inconvenience that the cutting blade 15 cannot be replaced because the locking pin is missing.

[0009]

The distal end of the lever 19 protrudes from the U-shaped groove 20 so that the lever 19 can be pinched when the lever 19 is rotated. For this reason, when grass or trees are caught on the tip of the lever portion 19 during the mowing operation, the lever portion 19 rotates and comes off from the U-shaped groove portion 20, and the lock pin 17 is moved to the lock position by the urging force of the spring 18. There is a disadvantage that the cutting blade holder 11 and the lock pin 17 are damaged due to the sliding engagement of the lock pin 17 with the engaging recess 16 of the rotating blade holder 11.

[0010]

Means for Solving the Problems The invention according to claim 1 is:
A case is provided for rotatably storing and holding a cutting blade shaft to which a disk-shaped cutting blade is detachably connected. A rotating body that rotates integrally with the cutting blade shaft is connected to the cutting blade shaft, and the rotation is performed. A lock pin slidably and rotatable between a lock position in which an engagement recess is formed in the body and a lower end portion is engaged with the engagement recess, and a lock release position in which the engagement state with the engagement recess is released. Is attached to the case, and an urging body for urging the lock pin toward the lock position is provided, a bent lever portion is formed at an upper end of the lock pin, and the lock pin is slid to the unlock position. In the cutting blade shaft lock device of the brush cutter, wherein the lever portion is held by the holding portion provided on the case by rotating the lever, the lever portion held by the holding portion is held by the holding portion. Solve The rotation restricting protrusion for restricting that rotates in the holding release position to thereby be positioned within the rotation range of the lever portion provided on the case.

According to a second aspect of the present invention, a case for rotatably storing and holding a cutting blade shaft to which a disk-shaped cutting blade is detachably connected is provided, and the cutting blade shaft is integrated with the cutting blade shaft. A locking position for connecting a rotating body that rotates to the rotating body and forming an engaging recess in the rotating body, a lower end portion engaging with the engaging recess, and a lock releasing position for releasing an engagement state between the engaging recess. A lock pin that is slidable and rotatable is attached to the case, and an urging body that urges the lock pin toward the lock position is provided, and a bent lever portion is formed at an upper end of the lock pin. In a cutting blade shaft lock device of a brush cutter, the lever portion is engaged with a U-shaped groove formed in the case by rotating the lock pin slid to an unlock position. The length dimension of the U The tool hook portion for hooking the tool to slip the locking pin in the direction against the biasing force of the spring so as to form sized to fit in portion provided on the locking pin.

[0012]

According to the first aspect of the present invention, the lock pin is maintained at the unlocked position by sliding the lock pin to the unlocked position and then rotating the lock pin to hold the lever portion by the holding portion. In this state, the mowing operation is performed by rotating and driving the mowing blade shaft and the mowing blade. At the time of this mowing operation, even if grass or trees are caught on the lever portion held by the holding portion, the lever portion is released from the holding state by the holding portion by the rotation restriction by the rotation restricting projection to the holding release position. Without being rotated, the lock pin is maintained in the unlocked position. Thus, during the mowing operation, the lever is prevented from rotating to the holding release position and the lock pin is prevented from sliding to the lock position, and the lock pin is engaged with the engaging recess of the rotating body that is driven to rotate. This prevents an accident that the rotating body and the lock pin are damaged.

According to the present invention, the lock pin is slid to the unlock position, and then the lock pin is rotated to engage and hold the lever portion in the U-shaped groove so that the lock pin is in the unlock position. The mowing operation is performed by rotating the mowing blade shaft and the mowing blade in this state. Since the length of the lever portion is formed to fit within the U-shaped groove portion, it is possible to prevent grass and trees from being caught on the lever portion during mowing work and to prevent grass and trees from being caught on the lever portion. The hook prevents the lever from being detached from the U-shaped groove, the lever is maintained in a state of being engaged and held in the U-shaped groove, and the lock pin is maintained in the unlocked position. Therefore, during the mowing operation, the lever is prevented from pivoting to the position where it is disengaged from the U-shaped groove and the lock pin is prevented from sliding to the lock position, and the engagement of the rotating body whose lock pin is driven to rotate is prevented. The occurrence of an accident in which the rotating body and the lock pin are damaged by engaging with the concave portion is prevented. In addition, since the lever is engaged with the U-shaped groove and held by the U-shaped groove, the tool is lifted out of the U-shaped groove by applying a force against the urging force of the spring by hooking the tool on the tool hook of the lock pin. Then, it becomes possible to put a finger on this lever portion and to rotate the lever portion in a direction away from the U-shaped groove portion.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the invention according to claim 1 will be described with reference to FIGS. The same parts as those described in FIGS. 8 to 11 are denoted by the same reference numerals, and description thereof will be omitted (the same applies hereinafter). A cutting blade shaft 6 is rotatably housed and held in the case 3, and a cutting blade holder 11 and a cutting blade 15, which are rotating bodies, are detachably connected to the cutting blade shaft 6. A lock pin 17 is slidably and rotatably attached to the case 3.
The outer peripheral portion of the spring 7 is a biasing body that biases the lock pin 17 toward a lock position in which the lower end of the lock pin 17 engages with the engaging recess 16 formed in the cutting blade holder 11.
8 are attached.

The upper end of the case 3 has a U-shaped groove 20 as a holding portion for engaging and holding a lever 19 bent at the upper end of the lock pin 17, and the U-shaped groove. The lever portion 19 engaged with and held at 20 is shown in FIG.
And a rotation restricting projection 21 for restricting rotation to the holding release position indicated by the two-dot chain line. The distal end of the lever portion 19 engaged with and held by the U-shaped groove portion 20 projects from the U-shaped groove portion 20 so that the lever portion 19 can be pinched when the lever portion 19 is rotated. Also,
As shown in FIG. 3, the rotation restricting projection 21 is
Are formed so as to have the highest central part and become gradually lower toward the U-shaped groove part 20. Further, on the upper end of the case 3, a guide projection 2 serving as a guide when rotating the lever portion 19 shown by a two-dot chain line in FIG.
2 are formed. In addition, this projection 22 for guides
As shown in FIG. 4, the case 3 is formed so as to be inclined such that the center of the case 3 is the highest and gradually decreases toward the outer periphery.

In such a configuration, during the mowing operation, as shown in FIG. 2, the lock pin 17 is slid to the unlocked position and the lock pin 17 is rotated to move the lever portion 19 of FIG. As shown in the solid line and FIG. 2, the U-shaped groove 20 is engaged and held.

Here, as shown in the solid line in FIG. 1 and in FIG. 2, the lever 19 is engaged and held in the U-shaped groove 20 and the cutting blade shaft 6 and the cutting blade 15 are driven to rotate to perform the cutting operation. In this case, grass and trees are caught on the tip of the lever portion 19, and a force acts on the lever portion 19 in a direction for rotating the lever portion 19 to a holding release position shown by a two-dot chain line in FIG. Even so, the lever portion 19 comes into contact with the rotation restricting projection 21 to restrict the rotation operation to the holding release position. Therefore, during the mowing operation, the lever 19 is prevented from rotating to the holding release position and the lock pin 17 is prevented from sliding to the lock position, and the lock pin 17 is rotated by the engagement of the cutting blade holder 11. The occurrence of an accident that the cutting blade holder 11 and the lock pin 17 are damaged by engaging with the mating recess 16 is prevented.

In addition, structurally, only the rotation restricting projection 21 is formed on the conventional product, and the structure is extremely simple.

Next, an embodiment of the invention according to claim 2 will be described with reference to FIGS. In this embodiment, the length of the lever portion 19 is formed so as to fit in the U-shaped groove portion 20. Further, a tool hooking portion 25 for hooking an engaging portion 24 formed on a cutting blade replacement wrench 23 which is a tool for sliding the lock pin 17 in a direction against the urging force of the spring 18 is formed on the lock pin 17. Have been. The cutting blade replacement wrench 23 is a tool for loosening or tightening the bolt 13 when the cutting blade 15 is replaced.

In such a configuration, the entire lever portion 19 engaged and held in the U-shaped groove portion 20 is
The grass and trees are prevented from being caught on the lever portion 19 during the mowing operation, and the grass and trees are caught on the lever portion 19 during the mowing operation. The lever 19 is kept engaged and held in the U-shaped groove 20, and the lock pin 17 is maintained in the unlocked position. For this reason, it is possible to prevent the lever portion 19 from being disengaged from the U-shaped groove portion 20 during the mowing operation, rotating to the holding release position indicated by the two-dot chain line in FIG. 5, and sliding the lock pin 17 to the lock position. This prevents the locking pin 17 from engaging with the engaging recess 16 of the rotating blade holder 11 and damaging the blade holder 11 and the lock pin 17.

Next, when the lever 19 is engaged and held in the U-shaped groove 20, a finger is put on the lever 19 because the tip of the lever 19 does not protrude from the U-shaped groove 20. 6 and 7, the engaging portion 24 of the cutting blade replacement wrench 23 is hooked on the tool hooking portion 25 of the lock pin 17 to resist the urging force of the spring 18. By applying an upward force, the lever 19 is lifted from the U-shaped groove 20. Therefore, a finger is hooked on the raised lever 19 and the lever 19 is shown by a two-dot chain line in FIG. It can be rotated to the holding release position.

[0022]

According to the first aspect of the present invention, a rotating body integrally rotating with the cutting blade shaft is connected to a cutting blade shaft rotatably housed and held in a case, and an engagement formed on the rotating body. A lock pin slidably and rotatable is attached to the case to a lock position for engaging the concave portion and a lock release position for releasing the engaged state with the engaging concave portion, and the lock pin is directed to the lock position. An urging body for urging was provided, a bent lever portion was formed at an upper end portion of the lock pin, and the lever portion was provided on the case by rotating the lock pin slid to an unlocked position. In the cutting blade shaft lock device of the brush cutter, which is held by the holding portion, a rotation control that restricts a lever portion held by the holding portion from turning to a holding release position for releasing the holding state by the holding portion. Sudden Since the provided is allowed in case located within the rotation range of the lever, even if caught grass and trees to the lever portion which is held by the holding portion during Kari払 work,
Due to the rotation restriction by the rotation restricting projection, the lever portion is not rotated to the holding release position for releasing the holding state by the holding portion, and the lock pin can be maintained at the lock releasing position. It is possible to prevent the lever portion from rotating to the holding release position and to prevent the lock pin from sliding to the lock position. Therefore, the lock pin is engaged with the engagement recess of the rotating body being driven to rotate. Therefore, it is possible to prevent the occurrence of an accident that the rotating body or the lock pin is damaged.

According to a second aspect of the present invention, a rotating body integrally rotating with the cutting blade shaft is connected to a cutting blade shaft rotatably housed and held in a case. A slidable and rotatable lock pin is attached to the case to a lock position for engagement and a lock release position for releasing the engagement with the engagement recess, and the lock pin is urged toward the lock position. A U-shaped member is formed by forming a bent lever portion at the upper end of the lock pin and rotating the lock pin slid to the unlock position by rotating the lock pin. In the cutting blade shaft lock device of the bush cutter designed to engage and hold the groove portion, the length of the lever portion is formed so as to fit in the U-shaped groove portion, so that grass and trees are attached to the lever portion during the brushing operation. That it gets caught Can be prevented, thus, the lever portion by grass and trees catching on the lever portion is U
It is possible to prevent the lock pin from sliding out of the U-shaped groove and the lock pin from sliding to the locked position during the mowing operation. It is possible to prevent the occurrence of an accident in which the lock pin is engaged with the engagement concave portion of the rotating body that is being driven to rotate, thereby damaging the rotating body and the lock pin. Since the lock pin is provided with a tool hook for hooking a tool for sliding in the direction opposite to the direction, the tool is hooked on the tool hook of the lock pin, and by applying a force in a direction against the urging force of the spring, The lever portion engaged and held in the U-shaped groove portion can be lifted from the U-shaped groove portion, and the lever portion is lifted from the U-shaped groove portion by rotating the lever portion with a finger. Has the effect of such an operation for sliding the lock pin to the lock position can be easily performed with removed from the U-shaped groove.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a front view showing a part in section.

FIG. 3 is a sectional view taken along line AA in FIG.

FIG. 4 is a sectional view taken along line BB in FIG.

FIG. 5 is a plan view showing an embodiment of the invention according to claim 2;

FIG. 6 is a front view showing a part in section.

FIG. 7 is a side view showing a state in which a wrench for replacing a cutting blade is hooked on a lock pin.

FIG. 8 is a vertical sectional side view showing a conventional example.

FIG. 9 is a front view partially showing a state in which a lock pin is slid to a lock position.

FIG. 10 is a front view showing a state in which a lock pin is slid to a lock release position, with a part thereof in section.

FIG. 11 is a plan view.

[Explanation of symbols]

 3 Case 6 Cutting Blade Shaft 11 Rotating Body 15 Cutting Blade 16 Engagement Recess 17 Lock Pin 18 Biasing Body 19 Lever 20 Holding Section, U-Shaped Groove 21 Rotation Restriction Projection 23 Tool 25 Tool Hook

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takao Shimojo 1-1-1 Ishiba, Matsumoto City, Nagano Prefecture Inside the Matsumoto Plant of Ishikawa Shima Shibaura Machinery Co., Ltd. (72) Inventor Hideki Kama 1-chome Ishiba, Matsumoto City, Nagano Prefecture No.1-1 Ishikawa Shima Shibaura Machinery Co., Ltd. Matsumoto Plant

Claims (2)

(57) [Scope of request for utility model registration] 1. A case for rotatably storing and holding a cutting blade shaft to which a disk-shaped cutting blade is detachably connected, wherein a rotating body that rotates integrally with the cutting blade shaft is provided on the cutting blade shaft. An engaging recess is formed in the rotating body while being connected, and the lower end is slidably and rotationally slidable between a locked position for engaging the engaging recess and an unlocked position for releasing the engaged state with the engaging recess. A movable lock pin is attached to the case, and an urging body for urging the lock pin toward the lock position is provided. A bent lever portion is formed at an upper end of the lock pin, and the lock pin slides to the unlock position. In the cutting blade shaft lock device of the brush cutter, wherein the lever portion is held by the holding portion provided on the case by rotating the lock pin, the lever portion held by the holding portion is By holding part A cutting blade shaft lock for a brush cutter, wherein a rotation restricting projection for restricting rotation to a holding release position for releasing a holding state is provided in the case within a rotation range of the lever portion. apparatus. 2. A case for rotatably storing and holding a cutting blade shaft to which a disk-shaped cutting blade is detachably connected, wherein a rotating body which rotates integrally with the cutting blade shaft is provided on the cutting blade shaft. An engaging recess is formed in the rotating body while being connected, and the lower end is slidably and rotationally slidable between a locked position for engaging the engaging recess and an unlocked position for releasing the engaged state with the engaging recess. A movable lock pin is attached to the case, and an urging body for urging the lock pin toward the lock position is provided. A bent lever portion is formed at an upper end of the lock pin, and the lock pin slides to the unlock position. The lever portion is formed on the case by rotating the lock pin
In the cutting blade shaft lock device of the brush cutter, which is adapted to be engaged and held in the U-shaped groove portion, the length of the lever portion is formed so as to fit in the U-shaped groove portion, and the lock pin is applied to the urging force of the spring. A cutting blade shaft lock device for a brush cutter, wherein a tool hook portion for hooking a tool for sliding in a direction opposite to the lock pin is provided on the lock pin.