JP3494290B2 - Cutting blade drive mechanism of self-propelled mower - 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 drive mechanism of a mowing machine for mowing weeds and the like.

[0002]

2. Description of the Related Art In this type of mower, a spring material is interposed between a cutting blade and a drive shaft, and when the cutting blade contacts an obstacle such as a stone or a tree stump, the cutting blade slips and rotates. Japanese Patent Application Laid-Open No. 7-236331 discloses a technique for preventing the cutting blade and the drive mechanism from being damaged and absorbing the impact. However, this technique relates to a so-called mower in which only a motor-driven cutting blade is provided at the end of a long pipe, and a spring member is provided in close contact with the cutting blade at the bottom end, so dust and weeds are not generated. It is easy to enter the drive part, and no consideration is given to its assembly.

[0003]

SUMMARY OF THE INVENTION The present invention is a self-propelled mower having traveling wheels, which smoothly takes in weeds and the like, and prevents dust from entering the cutting blade drive unit and winding the weeds. It is intended to prevent damage to the airframe even when it is overloaded.

[0004]

[Means for Solving the Problems] In a self-propelled mower that is equipped with a mowing part 1 at the front of the machine body, a traveling wheel 2 and a prime mover 3 at the rear part, and is movable by operating an operation handle 4, the mowing part 1 is arranged to move forward. The drive shaft 8 is hung from the transmission case 7 at the upper part while being covered with a cover 6 having a predetermined height for opening the insertion port 5 and guiding the weeds to be taken in. A seat 10 is provided so as to be rotatable integrally with the drive shaft 8, a collar 11 and a cutting blade 12 are loosely fitted to the drive shaft 8 at a lower portion thereof, and a blade presser 13 at a lower end is fastened to the drive shaft 8 with a bolt 14 to cut the blade. 12
To drive the self-propelled mower, an elastic body 16 is interposed between the seat 10 and the recess 15 provided on the upper surface of the collar 11 to allow the cutting blade 12 to rotate when overloaded. The structure of the mechanism. Further, a winding prevention cylinder 9 and a receiving seat 10 are provided at the base of the drive shaft 8 so as to be rotatable integrally with the drive shaft 8, and a collar 11 is interposed below the lower part of the cylinder 9 to form an upper cutting blade 121 and a lower cutting blade 1.
In order to fix the cutting blades 121 and 122 by loosely fitting 22 to the driving shaft 8 and further fixing the blade pressing member 13 at the lower end to the driving shaft 8 with the bolt 14, a concave portion 15 provided on the upper cutting blade 121 and the upper surface of the collar 11
The cutting blade drive mechanism of the self-propelled mower is configured by interposing the elastic body 16 that allows the cutting blades 121 and 122 to rotate when they are overloaded. Further, a spring washer is used as the elastic body 16, and the spring washer 16 is interposed in a compressed state with a bending margin left.

[0005]

Since the present invention is constructed as described above, when the operation handle 4 is operated to start traveling by the traveling wheels 2, weeding by the mowing section 1 arranged at the front of the machine body is performed. Is done. That is, the weeds taken in through the intake port 5 at the front end of the cover 6 of the cutting unit 1 are cut by the cutting blade 12 while being guided to the upper surface of the cover 6 having a predetermined height. At the time of this mowing, a winding prevention cylinder 9 and a receiving seat 10 are provided on the base of the drive shaft 8 suspended from the transmission case 7 on the upper side so as to rotate integrally with the drive shaft 8, and the collar 1 is provided on the lower side thereof.
1 and the cutting blade 12 are loosely fitted to the drive shaft 8 and further the blade holder 1 at the lower end
3 is fixed to the drive shaft 8 with the bolts 14 and the cutting blade 12 is fixed, and elasticity is provided between the receiving seat 10 and the concave portion 15 provided on the upper surface of the collar 11 to allow rotation of both when the cutting blade 12 is overloaded. Since the body 16 is interposed, the cutting blade 12 abuts on a stone or a tree stump, and when the cutting blade 12 is overloaded with an elastic force larger than that set by the elastic body 16. , The cutting blade 12 slips with respect to the other rotating members to absorb the impact, and the cutting blade 1
2 and the drive mechanism are prevented from being damaged.

Further, a drive shaft 8 is hung from an upper drive case 7 so as to correspond to a cover 6 having a predetermined height for opening the intake port 5 and guiding the weeds to be taken in. Corresponding to this, a collar 11 is provided between the lower cutting blade 12 and the upper seat 10 as a spacer function, and an elastic body 16 is interposed between the collar 11 and the seat 10. The elastic body 16 can be provided at a high position, and it is possible to reduce the occurrence of dust and weeds invading and winding. Further, since the elastic body 16 is provided by being fitted into the concave portion 15 provided on the upper surface of the collar 11, the elastic body 16 can be easily held in a stable state in the disassembling and assembling operation such as replacement when the cutting blade 2 is worn. You can do the work. According to the second aspect of the present invention, the cutting blades 121 and 122 are provided in upper and lower two stages for improving the cutting performance, and the collar 11 located between the upper cutting blade 121 and both cutting blades 121 and 122.
Since the elastic body 16 is interposed between the elastic member 16 and the recess 15 provided on the upper surface, the cutting blades 121, 122 slip and rotate when the upper cutting blade 121 or the lower cutting blade 122 is overloaded. It can absorb impact and prevent damage. According to the invention of claim 3, a spring washer is used as the elastic body 16 and the spring washer 16 is interposed in a compressed state with a bending margin left, and the compression force can be easily adjusted. , Can be constructed at low cost.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION In the illustrated example, a mowing machine is provided with a mowing section 1 at a front part of a machine body, a traveling wheel 2 and a prime mover 3 at a rear part, and performs mowing work while traveling by operating an operation handle 4. . A gear box 41 is provided in the center of the machine body, and a transmission shaft cylinder 17 and a support rod 18 are provided on both sides of the gear box 41.
Is extended, a transmission case 19 and an arm 20 are hung from the ends thereof, and the traveling wheel 2 having a horizontally long cylindrical shape is rotatably supported at the lower end thereof. Reference numeral 21 is a cover that covers the upper portion of the traveling wheel 2. A mounting frame 22 is extended from the lower part of the gear box 41 toward the front, a cover 6 of the mowing part 1 is attached to the lower surface of the mounting frame 22, and the center of the transmission case 7 is connected to the tip thereof. The transmission case 7 is formed in a slender shape in the left-right direction along the lower surface of the cover 6, and the central mounting portion 23 thereof is projected upward from the opening of the cover 6 and attached to the mounting frame 22 as described above.

The drive shafts 8, 8 are rotatably held by bearings 24, 24 located vertically on the left and right sides of the transmission case 7, and the upper parts of the drive shafts 8, 8 are covered by a cover 6.
Pulleys 25, 25 are attached to extend upward from the opening of the. Further, a pulley 26 attached to an output shaft below the gear box 41 and a belt 27 are wound around these pulleys 25, 25 so that the drive shafts 8, 8 can be respectively rotated inward. Reference numeral 28 denotes a cover, which covers these transmission parts.

At the top of the gear box 41, a mounting portion 29
A handle rod 30 is extended rearward and upward through the operation handle 4 to provide an operating handle 4. The operation handle 4 is provided with an accelerator lever 31 connected to the prime mover 3, a vertical adjustment lever 32 for the handle rod 30, a clutch lever 33 for connecting and disconnecting power to the traveling wheels 2, and the like. Reference numeral 34 is a mounting rod formed in an arch shape in a side view. The base is attached to the center of the machine body, and a guide wheel 35 is provided at the front end. Also 36
Is a grass collection guide. The drive shafts 8 and 8 are held by the bearings 24 and 24 on both left and right sides of the transmission case 7 and hang down as described above, and the seat 10 is welded to the base portion thereof. Winding prevention cylinder 9 that covers the holding portion 37
Are welded together, and these are integrally rotatable with the drive shaft 8. 40 is a spacer, which is the upper and lower bearings 24,
It is provided between 24.

Below the seat 10, a thick cylindrical collar 1 is provided.
1 and a spindle-shaped cutting blade 12 are loosely fitted to the drive shaft 8. The right and left cutting blades 12, 12 are slightly different in the vertical position. Reference numeral 13 is a blade retainer, which is partially fitted to the lower end of the drive shaft 8 and fixed to the drive shaft 8 with a bolt 14. A recess 15 is formed on the upper surface of the thick collar 11, and an elastic body 16 including a shim 38 and a spring washer is fitted therein.
The spring washer 16 has a nominal diameter of 1 inch and a height of 12.8 mm as shown in (a) of FIG.
It is set to be compressed to 0.6 mm, fitted with a bending margin of about 4 mm, and slipped under a load of about 100 kg. Reference numeral 39 is a gap between the seat 10 and the upper surface of the collar 11.
Further, the bolt 14 is tightened so that a force acts in the tightening direction when a load is applied to the cutting blade 12, and one side of the drive shafts 8 that rotate in opposition to each other is a left screw. Also, FIG.
The cutting blade 12 shown in FIG. 2 is composed of two upper and lower blades, and the upper cutting blade 121 is loosely fitted between the receiving seat 10 and the collar 11, and the concave portion is provided on the upper surface of the upper cutting blade 121 and the collar 11. 15
An elastic body 16 is interposed between the and. Also, the upper cutting blade 12
The lower cutting blade 122 and the lower cutting blade 122 are different in phase from each other by 90 degrees, and the mounting heights of the left and right drive shafts 8 and 8 are different from each other, so that the overlapping cutting blades 121 and 121 can be prevented from interfering with each other. is there.

A driving wheel 2 and left and right cutting blades 1 are driven by a prime mover 3.
2 and 12 are driven and the operation handle 4 is operated to perform the mowing work. The weeds are guided by the grass collection guide 36 from the front intake 5 into the cover 6 of a predetermined height, and are cut by the left and right cutting blades 12, 12 facing each other and rotating inward. Some weeds are dense and bulky, and some weeds exceed 1 m in height. A space of a predetermined height is required for taking in and cutting them. Therefore, the collar 11 is provided above the cutting blade 12. A sufficient height is secured by interposing it, and mowing is performed without winding or clogging. Further, the cover 6 that secures this height can prevent weeds and foreign matter from scattering and can perform work safely. During this mowing operation, when the cutting blade 12 comes into contact with a stone or a tree stump and the cutting blade 12 is overloaded by an elastic force set by the spring washer 16, the cutting blade 12 is It slips with respect to other rotating members to absorb the impact and prevent damage to the cutting blade 12, the drive mechanism, and the like.

Further, a drive shaft 8 is hung from an upper drive case 7 correspondingly to a cover 6 having a predetermined height for opening the intake port 5 and guiding the weeds to be taken in. The length of the drive shaft 8 is long. Corresponding to this, a collar 11 is provided between the lower cutting blade 12 and the upper seat 10 as a spacer function, and a spring washer 16 is interposed between the collar 11 and the seat 10. The spring washer 16 can be provided at a high position, and it is possible to reduce the occurrence of dust, weeds, and winding. Further, the spring washer 16 is provided so as to be fitted into the concave portion 15 provided on the upper surface of the collar 11, and the spring washer 16 is provided in the concave portion 1 at the time of disassembling and assembling when replacing the cutting blade 2 due to abrasion.
It is possible to easily carry out the work in a state in which it is fitted in the plate 5 and is stably held.

Further, in order to improve the cutting performance, the cutting blade 12 is vertically arranged in two stages.
When 1, 122 are provided, the weeds are shredded and the winding and the like are significantly reduced, and the upper cutting blade 121 and the recess 15 provided on the upper surface of the collar 11 located between the cutting blades 12 and 122 are provided. Since the spring washer 16 is interposed between the cutting blades 121 and 122, when the upper cutting blade 121 or the lower cutting blade 122 is overloaded, the cutting blade 121 or 122 slips and absorbs the impact. It can prevent damage. The elastic body 16 may use another elastic body such as a coil spring or a disc spring.

[0014]

[Brief description of drawings]

FIG. 1 is a plan view.

FIG. 2 is a side sectional view.

FIG. 3 is a front sectional view of a main part.

FIG. 4 (a) is a side view of the spring washer. (B) A side view of the spring washer when mounted.

FIG. 5 is a front view of a main part.

FIG. 6 is a front cross-sectional view of a main part showing another embodiment.

[Explanation of symbols]

1 reaper 2 running wheels 3 prime mover 4 operation handle 5 intake 6 cover 7 transmission case 8 drive shafts 9 Winding prevention cylinder 10 seat 11 colors 12 cutting blade 121 Upper cutting blade 122 Lower cutting blade 13 Blade holder 14 Volts 15 recess 16 Elastic body (spring washer)

Claims (3)

(57) [Claims] Claim: What is claimed is: 1. A self-propelled mower, comprising a mowing section (1) at a front part of a machine body, traveling wheels (2) and a prime mover (3) at a rear part thereof, which can be moved by operating an operation handle (4). 1) covers the front with a cover (6) of a predetermined height that guides the weeds to be taken in by opening the intake port (5), and hangs the drive shaft (8) from the upper transmission case (7), An anti-winding cylinder (9) and a seat (10) are provided at the base of the drive shaft (8) so as to rotate integrally with the drive shaft (8), and a collar (11) and a cutting blade (12) are provided under the drive shaft (8). It is loosely fitted to the drive shaft (8), and further the blade retainer (13) at the lower end is bolted (14) to the drive shaft (8).
In tightening and fixing the cutting blade (12), rotation of both is allowed when the cutting blade (12) is overloaded between the receiving seat (10) and the recess (15) provided on the upper surface of the collar (11). A drive mechanism for a self-propelled mower having an elastic body (16) interposed therebetween. 2. A winding prevention cylinder (9) and a seat (10) are provided on the base of the drive shaft (8) so as to be rotatable integrally with the drive shaft (8), and a collar (11) is interposed in the lower part thereof. Let the upper cutting blade (1
21) and the lower cutting blade (122) are loosely fitted to the drive shaft (8), and further the blade presser (13) at the lower end is attached to the drive shaft (8) by the bolt (1).
4) To stop and fix the cutting blades (121) and (122), the cutting blades (121) and (122) are provided between the upper cutting blade (121) and the recess (15) provided on the upper surface of the collar (11). Blade driving mechanism for a self-propelled mower, in which an elastic body (16) allowing rotation of both of them is interposed when it is overloaded. 3. A cutting blade for a self-propelled mower according to claim 1 or 2, wherein a spring washer is used as the elastic body (16) and the spring washer 16 is interposed in a compressed state with a bending margin left. Drive mechanism.