JPH07132013A - Structure for installing blade of mower - Google Patents

Abstract

PURPOSE:To provide a structure for installing a blade of a mower, capable of reducing both the number of parts and the production cost from those of a conventional structure and stably transmitting the torque from a driving shaft to the blade and good in operating efficiency. CONSTITUTION:This structure for installing a blade of a mower is constructed by freely fitting the blade 6 in a blade engaging part 5 at the lower end of a driving shaft 4, installing a blade supporting part 7, having a larger diameter than that of the blade engaging part 5 and capable of receiving the top surface part of the blade 6 and supporting the blade 6 at the lower end of the driving shaft 4, externally fitting a coned disc spring 8 for pressing and urging the blade 6 to the blade supporting part 7 in a coned disc spring engaging part 9 at the lower end of the driving shaft 4, pressing and deforming the central side of the coned disc spring 8 with a bolt 10 screwed into the center of the lower end surface of the driving shaft 4 so as to elastically nip the blade 6 between the compressed and deformed coned disc spring 8 and the blade supporting part 7. The blade engaging part 5 and the coned disc spring engaging part 9 are integrally installed with the blade supporting part 7 and the respective coned disc spring engaging part 9 and an engaging hole part (8a) of the coned disc spring 8 externally fitted in the coned disc spring engaging part 9 are formed into shapes of different diameters so as to provide the engagement incapable of mutually and relatively rotating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is characterized in that a blade is loosely fitted in a blade fitting portion provided at a lower end of a drive shaft and has a diameter larger than that of the blade fitting portion and receives an upper surface portion of the blade. A disc spring fitting for supporting a blade from above is provided at the lower end portion of the drive shaft, and a disc spring for pressing and urging the blade against the blade support portion is provided at the lower end portion of the drive shaft. Is externally fitted to the portion, and the center side of the disc spring is pressed and deformed by a bolt that is screwed into the center of the lower end surface of the drive shaft, and the blade between the disc spring and the blade support portion that is compressed and deformed is elastic. The present invention relates to a mower blade mounting structure configured to be sandwiched.

[0002]

2. Description of the Related Art Conventionally, in the above mower blade mounting structure, as shown in FIG. 5, a blade support portion C1 is spline-fitted to a spline formed at a lower end portion of a drive shaft, and the blade fitting portion is also provided. A cylindrical collar C2 with a flange and a disc spring fitting portion on the outer peripheral portion was fitted to the spline, and the blade 6 and the disc spring 8 were externally fitted to the collar C2.

[0003]

However, according to the above-mentioned conventional structure, since the drive shaft 4, the blade supporting portion C1 and the collar C2 with the collar are formed separately from each other, the number of parts is increased and the manufacturing cost is increased. It had the drawback of being expensive. In this type of mower blade mounting structure, the rotational force of the drive shaft 4 is transmitted to the blade 6 by the frictional force between the contact surfaces of the blade support portion C1 and the blade 6, and the blade 6 is overloaded. In this case, the drive shaft 4 is caused to slip by causing a slip on the contact surface between the blade support portion C1 and the blade 6, but in the above-mentioned conventional configuration, the disc spring 8 is formed into a cylindrical collar with a collar. Since the collar C2 is fitted on C2 and is rotatable with respect to the disc spring 8 together with the drive shaft 4, the torque at which the blade 6 slips may become unstable.
That is, when the blade 6 is prevented from rotating due to overload, the disc spring 8 may rotate integrally with the collar C2 and the disc spring 8 may stop integrally with the blade 6. In the case of, the slip occurs at the contact portion between the blade 6 and the outer peripheral portion of the disc spring 8, and in the case of the latter, the slip occurs at the contact portion between the disc spring 8 and the collar C2 with a collar. The slip generation torque is different for each. An object of the present invention is to provide a mower blade mounting structure capable of reducing manufacturing cost and stably transmitting a rotational force from a drive shaft to a blade.

[0004]

In order to achieve the above object, the mower blade mounting structure according to the present invention is characterized in that a blade fitting portion and a disc spring fitting portion are integrated with the blade supporting portion. The disc spring fitting portion and the fitting hole portion of the disc spring fitted on the disc spring fitting portion.
It is formed in different diameter shapes that are fitted to each other so that they cannot rotate relative to each other, and the effects thereof are as follows.

[0005]

That is, since the blade fitting portion and the disc spring fitting portion are provided integrally with the blade supporting portion, the number of members can be reduced as compared with the conventional case. Since the disc spring fitting portion and the fitting hole portion of the disc spring fitted on the disc spring fitting portion are formed in different diameter shapes so as to be fitted to each other so as not to rotate relative to each other. , The disc spring fitting part does not rotate with respect to the disc spring, so that torque transmission at the contact surface between the disc spring and the blade can be reliably maintained, and the torque when the blade slips can be stabilized. it can.

[0006]

As described above, the number of parts can be reduced as compared with the conventional one, so that the manufacturing cost can be reduced and the blade can be stably rotated.
It was possible to provide a mower blade mounting structure with good workability.

[0007]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 3 shows a mower M of a riding type lawnmower. The mower M is constructed by housing two drive shafts 4 in the housing 1 with a space left and right, and attaching a blade 6 to the lower end of each drive shaft 4.

Explaining the blade mounting structure of the mower, as shown in FIG. 1, a drive shaft 4 is rotatably inserted into a cylindrical vertical boss 2 of a housing 1 via a pair of upper and lower bearings 3. Then, the blade 6 is loosely fitted in the blade fitting portion 5 provided at the lower end portion of the drive shaft 4 and has a larger diameter than the blade fitting portion 5 and receives the upper surface portion of the blade 6 to support the blade 6 from above. The blade support part 7 is provided at the lower end of the drive shaft 4, and the disc spring 8 for pressing and urging the blade 6 against the blade support 7 is attached to the disc spring fitting part 9 provided at the lower end of the drive shaft 4. The center side of the disc spring 8 is pressed and deformed by the bolt 10 that is fitted externally and is screwed into the center of the lower end surface of the drive shaft 4, and between the vicinity of the outer periphery of the disc spring 8 that is compressed and deformed and the blade support portion 7. The blade 6 is configured to be elastically clamped.

As shown in FIGS. 1 and 2, the blade fitting portion 5, the blade support portion 7 and the disc spring fitting portion 9 are provided integrally with the drive shaft 4, and more specifically, the lower end of the drive shaft 4 is described. One of the parts is formed so that the fitting hole 6a of the blade 6 can be loosely fitted to form the blade fitting part 5, and one part above the blade fitting part 5 is fitted with the blade. The blade supporting portion 7 is formed to have a diameter larger than that of the portion 5, and a portion below the blade fitting portion 5 has a smaller diameter than the blade fitting portion 5 and a hexagonal cross-section having a different diameter. To form the disc spring fitting portion 9. The fitting hole portion 8a of the disc spring 8 is formed in a hexagonal cross-section having a different diameter so that the disc spring fitting portion 9 can be fitted into the disc spring fitting portion 9 so as to be relatively non-rotatable. In this way, since the disc spring fitting portion 9 and the fitting hole portion 8a of the disc spring 8 are formed to have different hexagonal cross-sections so as to be fitted into each other so that they cannot rotate relative to each other, the disc spring 8 The transmission of the rotational force of the drive shaft 4 from the disc spring 8 to the blade 6 due to the frictional force between the contact surfaces between the blade 6 and the blade 6 can be reliably maintained, and the blade 6 can be stably rotated. An annular groove 12 is formed on the upper surface of the blade supporting portion 7 so that the lower end peripheral portion of the boss 2 of the housing 1 is loosely fitted.

The bolt 10 has a hexagonal head 10a,
The center portion of the disc spring 8 is configured to be pressed by the hexagonal head portion 10a via the washer 13. The length from the lower end surface of the drive shaft 4 to the contact surface of the blade support portion 7 with respect to the blade 6 is such that the clamping force against the blade 6 by the blade support portion 7 and the bolt 10 via the disc spring 8 does not become too strong. When the overload is applied to the blade 6 due to the blade 6 colliding with an obstacle during the drive rotation of the blade 6, the contact between the blade support portion 7 and the blade 6 A slip occurs at the contact surface between the surface and the outer peripheral portion of the disc spring 8 and the blade 6, and the blade 6
It is designed to avoid damage to the.

[Other Embodiment] As shown in FIG. 4, the blade fitting portion 5, the blade support portion 7, and the disc spring fitting portion 9 are provided.
Is integrally formed with a ring-shaped member 11 which is separate from the drive shaft 4, and the hollow portion of the ring-shaped member 11 and the lower end portion of the drive shaft 4 can be fitted to each other by a spline hole 11a and a spline 4a. May be formed separately.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a mower blade mounting structure according to the present invention.

FIG. 2 is an exploded perspective view of a blade mounting structure.

[Figure 3] Bottom view of mower

FIG. 4 is a sectional view of another embodiment.

FIG. 5 is a sectional view of a conventional mower blade mounting structure.

[Explanation of symbols]

 4 Drive shaft 5 Blade fitting part 6 Blade 7 Blade support part 8 Disc spring 8a Fitting hole part 9 Disc spring fitting part 10 Bolt

Claims (1)

[Claims] 1. A blade (6) is loosely fitted in a blade fitting portion (5) provided at a lower end portion of a drive shaft (4) and has a diameter larger than that of the blade fitting portion (5). A blade support portion (7) for receiving the upper surface portion of 6) and supporting the blade (6) from above is provided at the lower end portion of the drive shaft (4), and the blade (6) is provided in the blade support portion (7). A disc spring (8) for pressing and biasing the disc spring to the disc spring fitting portion (9) provided at the lower end of the drive shaft (4),
A bolt (1) screwed into the center of the lower end surface of the drive shaft (4).
0), the center side of the disc spring (8) is pressed and deformed to elastically clamp the blade (6) between the compressed and deformed disc spring (8) and the blade support portion (7). In a mower blade mounting structure, the blade fitting part (5) and the disc spring fitting part (9) are provided integrally with the blade support part (7), and the disc spring fitting part (9) is provided. The mower and the fitting hole portion (8a) of the disc spring (8) externally fitted to the disc spring fitting portion (9) are formed in different diameters so as to be fitted in a mutually non-rotatable manner. Blade mounting structure.