JPH0424256B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a riding working machine equipped with a prime mover equipped with a governor.

Riding machines equipped with various types of work equipment, such as riding lawn mowers, tillers, snow blowers, etc., are generally configured so that a single prime mover drives the drive wheel and the work equipment, and the work equipment can perform various tasks. In order to ensure this, the prime mover is equipped with a governor that keeps the rotational speed of the prime mover constant against fluctuations in load.

On the other hand, since the driving force T generated by such a prime mover with a governor also includes the brake braking force R as one load, when the brake braking force R is A as shown in FIG. Power R is B
At this time, the governor characteristic operates so that the driving force T becomes b, and the driving force T increases, so that the stopping operation is not started until the brake braking force R exceeds the maximum output at the set rotational speed of the prime mover.

Therefore, in a riding work machine equipped with a prime mover equipped with a governor, the brake is operated in parallel with the clutch disengagement operation, and these operations are generally performed by operating a single pedal.

Therefore, if we consider, for example, when the vehicle is stopped, as shown in Fig. 6, if the brake pedal is depressed to first apply the brake braking force R and then perform the clutch disengagement operation C, then when the clutch disengagement operation C occurs, the brake is applied. Since the power R is large, sudden braking is likely to occur. Also, as shown in Figure 7,
If the configuration is such that when the pedal is depressed, clutch disengagement C is first performed, and then brake braking force R is applied, sudden braking is likely to occur as a sudden braking force is applied in a short period of time. When stopping, the vehicle may move backward until the braking force R reaches a certain value. These things are the same when starting, and it is easy to start suddenly, and on a slope, it is possible to go backwards before moving forward, and this type of riding work machine is configured to operate the clutch and brake with one pedal. There were problems with the clutch and brakes being difficult to operate.

The present invention has been devised in view of the above circumstances, and the object of the present invention is to provide a governor that can smoothly start and stop with simple operation, regardless of whether the vehicle is on flat ground or on a slope. To provide a riding work machine equipped with a prime mover.

In order to achieve the above-mentioned object, the present invention connects the pedal to a clutch via a clutch wire that is linked to the pedal's depressing motion, and the clutch starts disengaging from the side where the pedal starts to be depressed, and the pedal is a pedal that allows the clutch to completely disengage. An engagement mechanism using a long groove that transmits the acting force in the range from a predetermined depression position before reaching the depression position to the final pedal position, and an engagement mechanism using a long hole that acts only from the pedal side and transmits the acting force. The brake lever is connected to the brake lever through the clutch, and the brake lever is swung in a range from a predetermined pedal depression position to the final depression position before reaching the pedal depression position where the clutch is completely disengaged, increasing the braking force to the maximum, The brake lever is provided with an engagement mechanism that connects the brake lever to a handbrake lever that is operated to generate the force necessary for parking, and the engagement mechanism is actuated by an action from the side of the handbrake lever. It is characterized by having an elongated hole that engages only with the handle and transmits its acting force.

Hereinafter, a case where an embodiment of the present invention is applied to a riding lawn mower will be described.

FIG. 1 shows a side view of the riding lawn mower, and FIG. 2 shows a plan view thereof.

The riding lawnmower 1 includes a body frame 4 supported by two front wheels 2, 2 and two rear wheels 3, 3. An engine 5 with a governor is mounted on the front part of the body frame 4, and an output shaft 6 of the engine 5 is mounted on the front and rear wheels. make it stand out.

The engine 5 is housed in a bonnet 7 provided at the front of the vehicle body frame 4, and a handle 8 for steering the two front wheels 2 is provided behind the bonnet 7.

In the embodiment, the engine 5 is an air-cooled engine, and a cooling air passage 12 is defined by a shroud 11, and outside air is taken in from an opening 14 opened on one side of the vehicle by a fan 13 attached to the rear of the engine output shaft 6. After the engine 5 is cooled, it is discharged to the outside through an opening 15 opened at the front of the vehicle, and an exhaust pipe 16 extends rearward with a muffler 17 interposed therebetween.

On the rear part of the vehicle body frame 4 is the handle 8.
A brake pedal 23 which also serves as a clutch pedal is provided on the floor 22 below the handle 8, and a gear shift lever 24 and a side brake lever 2 are provided on one side of the seat 21.
5 will be placed.

The lawn mower 31 is disposed below the vehicle body frame 4 between the front wheels 2 and the rear wheels 3, and the lawn mower 31 is connected to a vertical adjustment mechanism 32 to adjust the mowing height of the lawn. freely configure.

The lawn mower 31 includes a cutter blade 33 and a housing 34 that accommodates the cutter blade 33. A pulley 36 is attached to the end of the shaft portion 35 of the cutter blade 33, and an output shaft 6 projects forward from the engine 5. The pulley 41 attached to the part and the pulley 36 are connected to the intermediate pulley 42 and the belts 43, 44.
etc., and the cutter blade 33 is rotated at a constant speed at a constant engine rotation speed by a governor.

A transmission mechanism 51 is disposed below the seat 21 between the two rear wheels 3, 3, and a joint 53,
Drive shaft 54, joint 55, clutch 56
The transmission of the engine output to the rear two wheels 3, 3 can be freely configured.

Next, referring to FIG. 3, the brake pedal 2
3. Gear shift lever 24, side brake lever 25
Explain how it works.

First, the shift lever 24 will be explained. The shift lever 24 is swingable in two mutually orthogonal directions via support shafts 61 and 62, and the swing around one support shaft 61 is caused by a change rod 63, a change arm 64, The transmission is transmitted to the transmission mechanism 51 via a shifter, etc., and in accordance with the swing angle of the transmission lever 24 about the support shaft 61, five forward speeds of F ₁ , F ₂ , F ₃ , F ₄ , and F ₅ are selected in the embodiment. The shift pattern 66 of the panel 65 in which the speed change lever 24 is incorporated has a guide groove 67 in a direction perpendicular to the support shaft 61 and a guide groove 67 parallel to the support shaft 61 to provide the speed ratio of reverse R1 speed. A plurality of engagement grooves 68 corresponding to the angles are formed, and one of the engagement grooves 68 is in a neutral position N.

A shaft 72 is connected above the other support shaft 62 via a bracket 71 so as to be parallel to the support shaft 62.
An arcuate arm 74 corresponding to the trajectory of a roller 73 attached to the intermediate portion of the speed change lever 24 is provided via the shaft 72, and both end bases of the arm 74 are rotatably attached to the shaft 72.

An end portion of a clutch wire 76 having a lost mechanism 75 interposed in the intermediate portion is attached to one base of the arm 74, and a branch piece 81 fixed to the base of the arm 74 and a clutch wire 76 fixed to the shaft 72 are attached. Support piece 82
A counter spring 83 is stretched between them, a bracket 84 and a damper arm 85 are attached to the middle part of the shaft 72 so as to rotate together with the shaft 72, and the clutch wire 76 is connected to the brake pedal 2.
Connect to 3.

A rod 87 connected to the operating lever 86 of the clutch 56 is connected to the bracket 84, and a single-effect damper 91 that applies resistance in the direction of extension is attached to the damper arm 85. A long hole 93 into which a mounting pin 92 is inserted is formed.

The arm 74 is provided with a resilient force such as a return spring of the operating lever 86.
It acts via the support piece 81, and the arm 74 is biased so as to come into elastic contact with the roller 73.

Therefore, for example, as shown in FIG.
When the arm 74 is tilted down from the guide groove 67 to the engagement groove 68 of F ₂ , the arm 74 falls down so as to come into elastic contact with the roller 73 , and the fall of the arm 74 causes the support piece 81 , the counter spring 83 , the support piece 82 , and the shaft 72 to fall. Clutch 56 is connected via rod 87, and damper 91 is in an extended state with mounting pin 92 located at the lower end of elongated hole 93. In this case, the damper 91 does not operate while the mounting pin 92 slides inside the elongated hole 93 as the damper arm 85 swings, and the damper 91 exerts its buffering function from the state where the mounting pin 92 is positioned at the lower end of the elongated hole 93. The clutch 56 is gradually extended, thereby slowly engaging the clutch 56. This damper 91 operates by tilting the gear shift lever 24 into the engagement groove 68.
The same applies when the brake pedal 23 is released from the depressed state.

On the other hand, considering the case where only the shift lever 24 is operated, the arm 74 of the brake pedal 23 falls and the clutch wire 76 is displaced, but this displacement is absorbed by the lost mechanism 75, and therefore the brake pedal 23 is operated by the shift lever 24. It doesn't move depending on the situation.

Further, when the gear shift lever 24 is tilted from each engagement groove 68 to the guide groove 67, the arm 74 is tilted by the roller 73, and the tilt of the arm 74 is transmitted to the bracket 84 and damper arm 85 in the same manner as described above, and the clutch is 56 is cut through the rod 87, and the damper 91 is in a contracted state with the mounting pin 92 located at the upper end of the elongated hole 93, and the stroke of the gear shift lever 24 in each engagement groove 68 and the stroke of the operating lever 86 of the clutch 56 are reduced. This difference is absorbed by the elongation of the counterspring 83. This clutch 5
6 and the operation of reducing the damper 91 are performed in the same way when the brake pedal 23 is depressed. On the other hand, when the gear shift lever 24 is tilted from the engagement groove 68 to the guide groove 67, the arm 74 falls and displaces the clutch wire 87, but this displacement is absorbed by the lost mechanism 75, so the brake pedal 23 is moved from the gear shift lever. Since the arm 74 separates from the roller 73 when the brake pedal 23 is depressed, the gear shift lever 24 does not move when the brake pedal 23 is depressed.

Next, the brake pedal 23 will be explained.
In the brake pedal 23, the base of an arm 102 including a pedal portion 101 is pivotally connected to a support shaft 103, the pedal portion 101 is urged upward by a return spring 104, and the upper limit position of the brake pedal 23 is regulated by a return stopper 105. floor 2
The lower limit position of the brake pedal 23 is regulated by a stopper 106 provided on the second side.

Another arm 107 extends from the base of the brake pedal 23 in a direction different from that of the arm, and the tip of the arm 107 is formed with an arc-shaped long groove 108 centered on the support shaft 103. One end of a clutch wire 76 is attached to the intermediate portion.

One end 111a of the brake rod 111 is inserted into the long groove 108, and a spring 112 is stretched between the brake rod 111 and the arm 107 to bias the rod end 111a against the end inside the long groove 108.

A turnbuckle 113 whose length can be freely adjusted is interposed in the middle part of the brake rod 111,
The turnbuckle 113 includes a cylindrical left member 114,
A rod-shaped right member 115 whose left half is inserted into the left member 114, and a long hole 116 of the left member 114.
Insert the pin 117 of the right member 115 into the left member 1.
14 and the right member 115 are formed to be integrally rotatable,
Further, the pin 117 is biased by a spring 118 to form the left member 114 and the right member 115 to move together in the length direction of the turnbuckle 113.

The other end of the brake rod 111 is a support shaft 121.
The bell crank 122 is connected to one end of the bell crank 122 which is pivotally supported by the bell crank 122, and the other end of the bell crank 122 is formed with an arc-shaped long groove 123 centered on the support shaft 121, and forms part of the brake braking mechanism 124 for the rear wheel 3. Support shaft 125
A rod 127 is attached to the tip of the brake lever 126, which swings around .The tip of the rod 127 is inserted into the long groove 123, and the spring 1
28 to press the tip of the rod 127 at the end of the long groove 123 on the brake lever 126 side;
A pin 129 is provided protruding from the middle portion of the brake lever 126.

The handbrake lever 25 is provided with an engagement pawl 131 that engages with a locking portion on the vehicle body frame side when lifted at a predetermined angle, and such engagement is achieved by pressing a push button 132.
is released by pushing the brake lever 25, and one end of the brake wire 133 is attached to the handbrake lever 25.

The other end of the brake wire 133 is attached to a plate 135 with a spring 134 interposed therebetween, and the brake lever 12 is inserted into a long hole 136 of the plate 135.
6 is inserted, and the spring 134 urges the end of the elongated hole 136 to press against the pin 129, and when the hand brake lever 25 is lifted, the brake lever 126 is always applied with a constant force via the spring 134. The handbrake 137 is formed to allow rocking motion, and the handbrake 137 is composed of the handbrake lever 25, the brake wire 133, the plate 135, the brake lever 126, etc.
The braking force S by the handbrake 137 is set to be slightly larger than the force required to stop the vehicle on a predetermined slope, for example, a 20° slope.

In the figure, 141 is a pilot lamp that lights up when the handbrake 25 is operated, and the long hole 123 of the bell crank 122 is for preventing the brake pedal 23 from moving when the handbrake lever 25 is operated. The elongated hole 136 at 135 is for preventing the handbrake lever 25 from moving when the brake pedal 23 is operated.

Next, referring to FIG. 4, the braking force R caused by operating the brake pedal 23 and the engagement and disengagement operation of the clutch 56 will be explained.

First, when the brake pedal 23 is depressed while the vehicle is moving forward, the clutch 56 begins to disengage via the clutch wire 76 (point a).
While the brake pedal 23 is being depressed, the clutch 56
is configured so that it can be cut completely (point b). Therefore, the engine driving force T decreases from (point a) to (point b) and becomes zero at (point b).

On the other hand, when the brake pedal 23 is depressed, the brake rod end 111a slides in the long groove 108, and the brake rod 111 is connected to the coil spring 1.
12 and moves toward the brake pedal 23 with a delay in the swinging of the brake pedal 23, but initially no brake force R is generated due to play in the brake braking mechanism 124. When the play eventually disappears (point c), the brake braking mechanism 124 is activated,
The brake rod end 111a is slid within the long groove 108, and the coil spring 112 is pulled while the brake rod 111 is moved toward the brake pedal 23 to generate a brake braking force R. The brake rod end 111a slides in the long groove 108 and moves the brake lever 126 little by little, so the amount increases gradually. The time at which the brake braking force R begins to be generated (point c) is set before the clutch 56 is completely disengaged (point b), and the clutch engagement/disengagement operation and brake braking operation are performed between (point b) and (point c). overlap.

Next, when the brake rod 23 is further depressed than the point where the clutch 56 is completely disengaged (point b), the brake rod end 111a is configured to be locked to the end of the long groove 108 (point d), and when the brake rod 23 is further depressed from this point (d point). When the brake lever 126 is pressed, the brake rod 111 follows the brake pedal 23 and moves.
is moved greatly to generate a large braking force R, and when the brake pedal 23 is in contact with the stopper 106 (point e), the depression operation is restricted, and the difference between the swing stroke of the brake lever 126 and the depression stroke of the brake pedal 23 is the turnbuckle. The pin 117 of 113 compresses the coil spring 118 and absorbs it by sliding in the long groove 116.

When performing operation B in which the brake pedal 23 is released from the state in which the brake pedal 23 is depressed, the operation is reverse to that described above, and in this case, the clutch 56 is slowly engaged due to the operation of the damper 91, and therefore the engine driving force T is It gradually increases as shown in (point b) and (point f), and S in the figure is the handbrake braking force.

Next, to explain the operation and effect, when stopping the vehicle from a running state, when the brake pedal 23 is depressed, an overlap occurs and a weak braking force R is generated before the clutch 56 is safely disengaged (point b). Since the brake pedal 23 starts braking, sudden braking caused by depression of the brake pedal 23 can be prevented. Also, brake pedal 2
Since only a weak brake braking force R is generated at the beginning of step 3, it is easy to operate the pedal, and when applying sudden braking, the brake braking force R is rapidly increased by rapidly depressing the brake pedal 23 (d point → point e), and therefore the vehicle can be braked easily.

When starting next time, when you take your foot off the brake pedal 23, the braking force R decreases rapidly from (point e) to (point d), and from (point d) to (c
On the other hand, due to the operation of the damper 91, the clutch 56 is slowly connected from (point b), and the engine driving force T and brake braking force overlap between (point b) and (point c). Since both R are small, the vehicle starts smoothly.

Next, when starting from a stopped state with the handbrake 137 applied on a slope, if you take your foot off the brake pedal 23 with the handbrake 137 applied, the braking force R will change from (point e) to (c On the other hand, due to the operation of the damper 91, the clutch 56 is slowly engaged from (point b), and the vehicle gradually starts running when the engine driving force T exceeds the handbrake braking force S (point j). After that, it is only necessary to release the handbrake 137, and anyone can easily start on a slope without having to go backwards on a slope as in the conventional case.

In the embodiment, the damper 91 was used to connect the clutch 56, but the damper 91 may not be used, and in this case, the brake pedal 23
In addition, in the embodiment, a mechanism is provided to generate a weak braking force R when the brake pedal 23 is depressed, but it is not necessary to provide a mechanism to generate such a weak braking force R. In this case, the brake pedal 23 may be depressed gradually to gradually increase the braking force.

As is clear from the above description, according to the present invention,
A riding work machine equipped with a prime mover with a governor that can brake and engage/disconnect the clutch with a single pedal.
Regardless of whether the vehicle is on flat ground or a slope, it can be started and stopped smoothly with simple operations.

[Brief explanation of drawings]

Fig. 1 is a side view of the riding lawnmower, Fig. 2 is a plan view of the same, Fig. 3 is a schematic diagram showing the operation of the brake pedal, gear shift lever, and handbrake lever, and Fig. 4 is a diagram showing the engine driving force due to pedal depression. Relationship diagram between brake braking force and handbrake braking force, 5th
The figure is a relationship diagram between engine driving force and brake braking force due to pedal depression, and Figures 6 and 7 are relationship diagrams between engine driving force, brake braking force, and clutch operation due to pedal depression of a conventional riding work machine. be. In the drawing, 1 is a riding lawn mower, 5 is an engine with a governor, 8 is a handle, 21 is a seat, 23 is a brake pedal, 24 is a gear shift lever, 25 is a side brake lever, 31 is a lawn mower, 76 is a clutch wire, 111 is the brake rod, 133 is the brake wire, 108 is the long groove, 123 is the long groove, 126
136 is a brake lever, and 136 is a long hole.

Claims (1)

[Scope of Claims] 1. A riding work machine equipped with a prime mover with a governor, in which a brake lever that generates travel brake braking force and a clutch that connects and disconnects travel power are operated with a single pedal, The pedal of the riding work machine is connected to the clutch via a clutch wire that is linked to the pedal depression operation, and the clutch starts disengaging from the side where the pedal starts to be depressed, and the pedal is at a pedal depression position where the clutch is completely disengaged. An engagement mechanism using a long groove that transmits the acting force in the range from the predetermined depression position before reaching the pedal end position, and an engagement mechanism using an elongated hole that acts only from the pedal side and transmits the acting force. and connected to the brake lever, and the brake lever is swung in a range from a predetermined pedal depression position to a pedal depression end position before reaching the pedal depression position where the clutch is completely disengaged, thereby increasing the braking force to a maximum; The brake lever is provided with an engagement mechanism that connects the brake lever to a handbrake lever that is operated to generate the force necessary for parking, and the engagement mechanism is actuated by an action from the side of the handbrake lever. A riding working machine characterized by being equipped with an elongated hole that only engages with the handle and transmits its acting force. 2. In claim 1, the braking force generated by depressing the pedal is
A riding working machine that is configured so that the pedal swing position increases gradually including the pedal swing position at which the clutch is completely disengaged, and increases rapidly at the end of pedal depression.