JPH04110431U - Brush cutter rotation restraint device - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the complexity associated with carrying a jig used to prevent the drive shaft 24 from rotating with the rotation of the tightening screw 38 when replacing the cutting blade 18. This will also prevent the loss of jigs while carrying or storing them. [Structure] The drive shaft 24 protrudes from the gear case 26 of the gear device 16, and the upper boss 34 and the lower boss 36 are fitted to the end of the drive shaft 24 so as to rotate integrally with each other, and pinch the cutting blade 18. The locking pin 56 is attached to the gear case 26 so as to be freely displaceable between an upper position and a lower position, and locks rotation of the upper boss 34 in the lower position.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to a rotation restraint device for brush cutters, and more specifically, to streamline the work of replacing mower blades. This invention relates to a rotation restraint device for a brush cutter that contributes to the above.

0002

[Conventional technology]

In a brush cutter, the drive shaft protrudes from the gear device, and the upper and lower bosses are The cutting blade is fitted to the drive shaft so that it rotates integrally with the proximal end and the distal end, and the cutting blade is attached to the upper boss. and the lower boss, and the tightening screw is attached to the tip of the drive shaft. Screw in and tighten the cutting blade, upper boss, and lower boss in the axial direction, and then rotate the cutting blade from the top to the top. It is clamped by the boss and lower boss.

0003 When replacing the cutting blade, it is necessary to loosen and retighten the tightening screws. In this case, it is necessary to prevent the drive shaft from rotating together with the tightening screw.

0004 For this reason, in Japanese Utility Model Application Publication No. 59-77820, protrusions are provided on opposing parts of both ends. A U-shaped spring is prepared, and when replacing the cutting blade, the spring is expanded and both protrusions are extended. Insert the cutter holder (upper boss) and gear case into the insertion hole. The relative rotation of the rotor and gear case, and therefore the relative rotation of the drive shaft with respect to the gear case. I try to restrict rotation.

[0005]

[Problem that the idea aims to solve]

The U-shaped spring disclosed in Japanese Utility Model Publication No. 59-77820 prevents the cutting blade from moving during the mowing operation. The worker must have the spring with him or her to be able to replace it. It is cumbersome and easy to lose while carrying or storing.

[0006] The purpose of this invention is to restrain the rotation of the drive shaft necessary for replacing the cutting blade. This method eliminates the hassle of carrying around jigs and prevents the loss of such jigs. An object of the present invention is to provide a rotation restraint device for a brush cutter that can perform the following functions.

[0007]

[Means to solve the problem]

This invention will be explained using reference numerals in the drawings that correspond to the embodiments. The brush cutter (10), which is the premise of this invention, has a drive shaft (24) protruding from the gear device (16). The first boss (34) and the second boss (36) are driven so that they are on the proximal side and the distal side, respectively. It is fitted into the moving shaft (24) so as to rotate integrally with it. In addition, the cutting blade (18) is connected to the first boss (34) and The drive shaft (24) is fitted between the first boss (34) and the second boss (36). It is clamped by the boss (36) of No. 2. In the brush cutter (10) of this invention, the locking The body (56) is attached to the outside of the gear case (26) of the gear device (16) so as to be able to move forward and backward toward the first boss (34). It is attached to the surface and locks the rotation of the first boss (34) at the position on the first boss (34) side. Ru.

[0008]

[Effect]

When replacing the cutting blade (18), displace the locking body (56) toward the first boss (34). Then, the first boss (34) is placed in a position on the first boss (34) side, and rotation of the first boss (34) is locked. Locking body (5 6) is attached to the gear case (26) of the gear device (16), and is also attached to the first boss (3). 4) is integrally rotatably fitted to the drive shaft (24), so the first bolt is secured by the locking body (56). As the gear case (34) is locked, the drive shaft (24) is restrained from rotating relative to the gear case (26). It will be done. After replacing the cutting blade (18), move the locking body (56) away from the first boss (34). and release the restriction on rotation of the first boss (34). As a result, the drive shaft (24) It can rotate freely relative to the gear case (26).

[0009]

【Example】

This invention will be described below with reference to embodiments shown in the drawings. FIG. 8 is a perspective view schematically showing the entire brush cutter 10. As shown in FIG. Brush cutter 10 extends for a long time The operating stick 12, the engine power unit 14 connected to the upper end of the operating stick 12, and the operating stick 12. A gear device 16 coupled to the lower end, and an engine drive device disposed on the bottom side of this gear device 16. From the force section 14 to the transmission shaft (not shown) in the operation stick 12 and the gear (not shown) in the gear device 16 ) is provided with a cutting blade 18 that is rotated by rotational power transmitted through handle 20 is fixed to the operating stick 12 so as to extend left and right, and the throttle lever 22 is fixed to the operating stick 12 so as to extend from side to side. It is attached to the tip of the dollar 20 and adjusts the throttle valve opening of the engine power section 14. .

0010 FIG. 1 is a diagram showing the structure of the tip of a brush cutter 10. The drive shaft 24 is a gear of the gear device 16. It protrudes downward from the case 26 and has a spline groove 28 at the lower end. ballbe The gear ring 30 is fastened within the gear case 26 by a snap ring 32, and is attached to the drive shaft 24. It is rotatably supported by the gear case 26. Collar 31 has a ball bearing 30 at the top end. The oil seal 33 is fitted onto the drive shaft 24 so as to come into contact with the inner ring, and the oil seal 33 is attached to the gear case 26. It is inserted between the inner periphery of the collar 31 and the outer periphery of the collar 31 to prevent the lubricating oil inside the gear case 26 from leaking. is prevented. The upper boss 34 and the lower boss 36 are respectively upper and lower. The spline fits into the spline groove 28 of the drive shaft 24, and the inner edge of the cutting blade 18 Pressure is applied from above and below. The tightening screw 38 has a locking washer 42 and a stabilizing washer on its shaft. After the plates 44 are fitted in order, they are screwed onto the drive shaft 24, and the upper boss 34, cutting blade 18, and lower boss 36 and the stabilizer plate 44 towards the collar 31. Along with tightening with tightening screw 38 , the cutting blade 18 is clamped by the upper boss 34 and the lower boss 36 from above and below, and is integrally connected to the drive shaft 24. Rotate to . The notch groove 50 is arranged upwardly at one location in the circumferential direction at the upper edge of the upper boss 34. It is formed at the same time. The pin retainer 52 is close to the upper boss 34 and is attached to the gear case 26. Fixed to the outer circumferential surface of the

[0011] 2 and 6 show the locking pin 56 in the upper and lower positions, respectively. 5 is a diagram showing the structure of a holding device 52 in a vertical cross section. FIG. The pin holding case 53 is attached to the pan screw 54. The locking pin 56 is L-shaped and is fixed to the outer peripheral surface of the gear case 26. A lateral protrusion 60 protrudes outward from the lateral guide groove 58 on the side wall of the case 53 and a pin retaining cage. The vertical portion 64 is movable downwardly from the lower guide groove 62 of the lower wall of the base 53. . The compression coil spring 66 is fitted into the vertical portion 64 of the locking pin 56, and the compression coil spring 66 is inserted into the vertical portion 64 of the locking pin 56, and abut against the side protrusion 60 and the lower wall of the pin holding case 53, respectively, and move the locking pin 56 upward. It is energizing. In the upper position, the vertical part 64 of the locking pin 56 goes into the pin holding case 53. It is pulled in and separated from the notch groove 50, and in the lower position it is inserted into the notch groove 50. has been done.

0012 3 and 7, the locking pin 56 is located at the upper locking portion 72 and the lower locking portion of the side guide groove 58, respectively. While it is locked at the stop 74, move the pin holding device 52 to the outside in the radial direction of the cutting blade 18. This is a diagram seen from above. The side guide groove 58 is bent and formed on the side surface of the pin holding case 53. An upper locking portion 72 and a lower locking portion 74 facing downward are provided at both ends. Locking pin 56 The lateral protrusion 60 has a compression coil spring 66 at the upper locking portion 72 and lower locking portion 74. is pressed from below and is in a locked state.

[0013] FIG. 4 is a bottom view of the pin holding device 52 of FIG. The lower guide groove 62 is a gear The locking pin 56 is formed to be elongated in the circumferential direction of the base 26 (Fig. 2), so that the locking pin 56 is Relative displacement relative to the pin holding case 53 in the circumferential direction of the gear case 26 by the length of the groove 62 It is now movable along the side guide groove 58.

[0014] 3, 4 and 7, the pin holding case 53 is located around the gear case 26 (FIG. 2). One side of the pin holding case 53 is opened, and the lid 68 closes the opening of the pin holding case 53. It is applied to the pin holding case 53 as shown in FIG. FIG. 5 is a front view of the lid 68. 4 lids 68 It is fixed to the pin holding case 53 with a pot machine screw 70.

[0015] The operation of the embodiment will be explained. Normally, the locking pin 56 locks the side protrusion 60 with the upper locking portion 72, as shown in FIGS. 3, and the vertical portion 64 of the locking pin 56 is separated from the notch groove 50. . Therefore, the rotation of the upper boss 34 is not restricted by the locking pin 56, and the rotation of the upper boss 34 is not restricted by the locking pin 56, and It is rotatable relative to 26. As a result, the drive shaft 24 is connected to the engine power section 14. When the cutting blade 18 rotates due to the rotational power from the cutting blade 18, the cutting blade 18 also rotates.

[0016] When replacing the cutting blade 18, the operator should pinch the tip of the lateral protrusion 60 of the locking pin 56. Then, it is moved downward along the side guide groove 58 against the biasing force of the compression coil spring 66. At the same time, rotate the cutting blade 18 by an appropriate amount to insert the lower end of the vertical portion 64 into the notch of the upper boss 34. After inserting it into the groove 50, the side protrusion 60 is locked with the lower locking part 74, and the locking pin 56 is locked. hold in the lower position. As a result, the upper boss 34 is prevented from rotating, and the drive shaft 24 is Rotation relative to the case 26 is restricted. After this, the tightening screw 38 is loosened. , is removed from the drive shaft 24, and the cutting blade 18 is also removed from the drive shaft 24 and replaced. After replacing After tightening the tightening screw 38 to the drive shaft 24, tighten the lateral protrusion 60 of the locking pin 56 sideways. The guide groove 58 is returned to the upper locking part 72, and the upper boss 34 is locked in the rotational direction by the locking pin 56. Cancel the stop.

[0017] In the illustrated embodiment, the upper boss 34 is rotated by inserting the locking pin 56 into the notch groove 50. However, other means such as holes or protrusions can be substituted for the cutout groove 50. be.

[0018]

[Effect of the idea]

In this invention, the locking body can freely move forward and backward toward the first boss of the gear case of the gear device. It is attached to the outside surface, and when replacing the cutting blade, the locking body is placed in the position on the first boss side. to lock the rotation of the first boss, and connect the drive shaft to the gear case via the first boss. Constrain the relative rotation of . Therefore, in preparation for replacing the cutting blade during mowing, the operator This eliminates the hassle of carrying a jig that restricts the rotation of the drive shaft, and It is possible to avoid a situation where the jig is lost during storage.

[Submission date] April 10, 1991

[Procedural amendment 1]

[Name of document to be amended] Specification

[Correction target item name] 0014

[Correction method] Change

[Correction details]

3, FIG. 4, and FIG. 7, the pin holding case 53 opens one circumferential side of the gear case 26 (FIG. 2), and the lid 68 closes the opening of the pin holding case 53. It is applied to the pin holding case 53 as shown in FIG. FIG. 5 is a front view of the lid 68. The lid 68 is fixed to the pin holding case 53 with four pan screws 70.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the structure of the tip of a brush cutter.

FIG. 2 shows the structure of the pin holding device in vertical section with the locking pin in the upper position;

FIG. 3 is a view of the pin holding device viewed from the outside in the radial direction of the cutting blade with the locking pin locked in the upper locking portion of the side guide groove.

FIG. 4 is a bottom view of the pin holding device of FIG. 3;

FIG. 5 is a front view of the lid.

FIG. 6 is a vertical cross-sectional view of the structure of the pin holding device with the locking pin in the lower position;

FIG. 7 is a view of the pin holding device viewed from outside in the radial direction of the cutting blade with the locking pin locked in the lower locking portion of the side guide groove.

FIG. 8 is a perspective view schematically showing the entire brush cutter.

[Explanation of symbols]

10 Brush cutter 16 Gear device 18 Cutting blade 24 Drive shaft 26 Gear case 34 Upper boss (first boss) 36 Lower boss (second boss) 59 Locking pin (locking body)

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[Procedural amendment]

[Submission date] April 10, 1991

[Procedural amendment 2]

[Name of document to be amended] Specification

[Correction target item name] Figure 5

[Correction method] Change

[Correction details]

FIG. 5 is a front view of the lid.

[Procedural amendment 3]

[Name of document to be amended] Specification

[Correction target item name] Explanation of code

[Correction method] Change

[Correction details]

[Description of symbols] I0 Brush cutter 16 Gear device 18 Cutting blade 24 Drive shaft 26 Gear case 34 Upper boss (first boss) 36 Lower boss (second boss) 56 Locking pin (locking body)

Claims (1)

[Scope of utility model registration request] [Claim 1] A drive shaft (24) protrudes from the gear device (16),
The first boss (34) and the second boss (36) are integrally rotatably fitted to the drive shaft (24) so that they are on the proximal end side and the distal end side, respectively, and the cutting blade (18) The first boss (34) and the second boss
is fitted onto the drive shaft (24) between the bosses (36) of the
In the brush cutter (10) held between the first boss (34) and the second boss (36), the locking body (56) can freely move forward and backward toward the first boss (34). The mower is attached to the outer surface of the gear case (26) of the gear device (16), and locks rotation of the first boss (34) at a position on the first boss (34) side. Rotation restraint device for the dust cutter.