JPS6148882B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention provides a drilling device in which a plurality of drilling teeth that move up and down are connected to a rotationally driven crank mechanism via a connecting rod, which is attached to a vehicle chassis. The present invention relates to a lawn care device in which a drilling device is driven forward by power.

[Conventional technology]

In golf courses and the like, it is important to keep the lawn well maintained to provide a desirable playing surface. To achieve this, it is desirable to drill a large number of small holes vertically at regular intervals on the surface of vegetation such as lawns, to allow ventilation to the roots of the plants through these small holes, and to provide water and fertilizer for the plants to grow. . However, it is extremely difficult to drill a large number of small holes efficiently, at high speed, and accurately over such a vast area of the earth's surface.

A ground surface ventilation hole drilling machine disclosed in Japanese Patent Publication No. Sho 36-17361 is already known as a device for efficiently carrying out such work.

In the device according to this publication, a large number of perforated teeth that are connected to a power rotation crank mechanism and move up and down are placed on a vehicle chassis that moves forward by the power, and a cam lift equal to the distance that the chassis advances during one rotation of the crank is provided. A rotary cam mechanism is used to sequentially move the drilling teeth backward at a constant speed so that they remain stationary in the horizontal direction relative to the ground while they are underground, and to return them rapidly forward while they are out of the ground, so that they are always on the ground surface. It can be inserted vertically and removed to continuously drill into the ground surface at high speed.

In this case, multiple sets of rotating crank mechanisms attached to a gate-shaped support frame fixed on the chassis are rotatably connected via a hinge joint to the lower end of a connecting rod extending downward from the crank arm. The reciprocating sliding rod and the perforating teeth fixed to its lower end are sequentially driven in the vertical direction. In order to guide the reciprocating sliding rod in the vertical direction, a sliding rod guide tube is provided which is fitted onto the rod, and the tip of the arm that can protrude in the horizontal direction is rotated by a spring. The horizontal movement of the guide cylinder is caused to follow the movement of the contact point which is constantly in contact with the cam mechanism and changes horizontally as the cam rotates, causing the reciprocating sliding rod and the drilling teeth to retreat and return rapidly forward. There is.

[Problem that the invention seeks to solve]

In a device with such a configuration, the connecting rod extending downward from the crank arm is rotatably connected to the reciprocating sliding rod via the hinge joint, so the rotational motion of the crank arm is converted into linear motion. It is transmitted to the drilling teeth, and the drilling teeth are always held in an upright position. As the upper end of the connecting rod rotates, it retreats relative to the chassis, but its retreating speed is not necessarily constant; it reaches zero at the intermediate front end position and reaches its maximum speed at the bottom dead center. Therefore, especially near the front end position, the vehicle speed exceeds the backward speed, so the perforating teeth, which are held vertically, are tilted forward by the forward force of the vehicle immediately after they begin to be inserted into the soil. This forward tilting effect does not pose much of a problem when the vehicle speed is low, but as the vehicle speed increases, problems such as breakage of the perforated tooth or the sliding rod integrated therein occur. This is because the structure is such that these members are always held upright in order to keep the drilling teeth and sliding rod stationary on the ground, and it is no longer possible to increase the chassis speed and perform drilling with high efficiency at a higher speed. Such a mechanism cannot cope with this problem.

Also, as a natural consequence of this configuration, the drilling device, including the drilling teeth, sliding rod, crank mechanism, guide tube, and cam mechanism, cannot be separated from the chassis body, for example, for maintenance or inspection, or for replacement with other device parts. However, it has the disadvantage that the structure is complicated.

The present invention eliminates the above-mentioned drawbacks and provides a lawn care device that is simple in construction and can be used at higher speeds.

[Means for solving problems]

As a means for solving the above problems, in the present invention, a drilling device includes an upper crank mechanism, a connecting rod hanging from the crank mechanism and directly connected to the drilling teeth, and an upper crank provided at the lower side of the crank mechanism. Another set of lower crank mechanisms whose rotation radius is slightly smaller than that of the upper crank mechanism is rotated in synchronization with the mechanism, and both ends are rotatably connected to the lower crank mechanism and the connecting rod, and are expandable and retractable by elastic members. The rear part of the vehicle chassis is formed into a U-shape that is open to the rear, and within the open space there are two pivots in the horizontal axis direction with the punching device provided at the front end thereof. We adopted a structure in which it is removably attached to a support shaft.

[Effect]

According to this invention, the perforating device provided separately and independently from the vehicle body is removable from the vehicle body, and the perforating teeth of the perforating device are directly connected to the connecting rod hanging from the upper crankshaft. Another set of crankshafts is connected to the tip of a horizontal lever that extends horizontally from the connecting rod, and by simultaneously rotating both crank mechanisms, the connecting rod and the perforated teeth that are integrated with it are held in a vertical position and lowered. This is done by being inserted into the device and then retracted.

As the crankshaft rotates, the drilling teeth descend and retreat relative to the vehicle body, and since the vehicle moves forward at approximately the same speed as this retreating speed, the drilling teeth remain stationary on the ground. In this case, even though the rotational speed of the crankshaft is approximately constant, the horizontal retraction speed of the upper end of the connecting rod is not necessarily constant; it is zero at the intermediate level of the front end position (it has the maximum speed in the vertical direction); Maximum speed is reached at bottom dead center. Therefore, if you try to lower the drilling tooth while retreating from the intermediate level, the drilling tooth whose tip is inserted into the soil shallowly will move forward depending on the vehicle speed because the drilling tooth and the connecting rod are integrated. tilted. Therefore, in this invention, the lower one of the two crank arms of the upper crank mechanism and the lower crank mechanism is formed in advance to have a slightly smaller diameter, and by utilizing the difference in diameter, the perforated tooth and the connecting rod integrated therewith are moved forward. By making it possible to tilt, it alleviates the reaction force caused by the forward tilting action that occurs immediately after the tip of the drilling tooth is vertically inserted into the ground, and prevents excessive force from acting on the drilling tooth and the connecting rod. . When the crankshaft further descends from the intermediate level and rotates between the horizontal and vertical positions, that is, around 45 degrees or more, the backward speed of the connecting rod increases, and the connecting rod moves backward at the forward vehicle speed or higher at bottom dead center. The connecting rod is returned to a vertical position and is inserted to the deepest point while stationary relative to the ground, and once it has passed the bottom dead center, it is pulled out in the reverse order to the above. In this way, even if the connecting rod is tilted forward or backward during the drilling operation, the connecting rod is held in the most comfortable state by the two crank mechanisms. Due to the slightly different radii of the arms, the horizontal lever cannot be connected at right angles to the connecting rod throughout the respective rotational phase angles of the crank arms. Therefore, in order to adjust this angular deviation, the horizontal lever is made of an elastic member and is extendable and retractable, and both ends of the horizontal lever are rotatably connected to the lower crank mechanism and the connecting rod, so that the connecting rod can be tilted forward. It can be tilted freely depending on the situation, etc., and
The elastic member allows the connecting rod to return to its upright position.

When the vehicle speed increases, the rotational speed of the crankshaft also increases in proportion to this, and the forward tilting effect on the perforated tooth and the connecting rod that is integrated with it also increases, but as described above, a correction mechanism for the connecting rod is constructed. Therefore, regardless of the speed of the vehicle, the perforating teeth always work smoothly, and a stationary effect on the ground can be obtained.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side view of the lawn care device 1. FIG. The lawn care device 1 comprises a four-wheel chassis 4 having a steerable front wheel 2 and a driven rear wheel 3. A seat 5 on which a worker sits is provided at the front of the chassis.
The main steering and control devices, such as the steering wheel, clutch, brakes and accelerator, are arranged in the same way as in conventional road vehicles.

The shape of the chassis is U when viewed from the top.
It consists of a letter-shaped frame (not shown), and its U-shaped open part opens toward the rear. A punching device 10, which will be described later, is removably attached to the chassis in this U-shaped open space by means of fixing members 6 provided on both side frames of the punching device 10.

In the case of this embodiment, an electrically started 16 horsepower gasoline engine is installed under the seat 5 as the vehicle drive unit, and the engine is connected to the rear wheels at the rear end of the chassis via a clutch, a speed change belt, etc. At the same time, the perforating device 10 is driven via a plurality of parallel V-belts 7 connected to pulleys driven by the output shaft of the clutch. Furthermore, when in use, this drilling device 10 stands upright on the ground as shown in the figure, but when not in use, it is provided with a hydraulic cylinder 8 so that it can be moved in a slightly forward tilted state as shown by the dotted line in order to protect the tips of the drilling teeth. . Note that a hydraulic pump and tank are separately provided to supply pressure oil to the hydraulic cylinder and other hydraulic drive parts (not shown).

Next, the punching device 10 will be explained. FIGS. 2 and 3 respectively show an enlarged side view and a front view (including a partially sectional view) of the punching device, and show the operating state of the punching device 10 when it is mounted on a vehicle. The drilling device 10 consists of two pairs of vertical and parallel steel plates 20a, 20b each having two crankshafts 12, 13. The upper crankshaft 12 is connected to four drilling heads 21 via a crank 14, a crank pin 15 and a connecting rod 16, and serves to vertically move these heads in the up and down direction. The connecting rod 16 is directly fixed to the drilling head 21, and the drilling head 21 is integrally formed with a plurality of hollow drilling teeth, and as the crankshaft 12 rotates, these drilling teeth change their respective phase angles with respect to the crankshaft. It descends one by one according to the order of displacement and is inserted into the soil. The drilling operation is performed by the drilling device 10.
This is done while moving the drilling tooth 22 forward, so this horizontal movement must be taken into consideration in order to hold the drilling tooth 22 vertically and move it forward.

Therefore, in order to hold the connecting rod 16 integral with the perforated teeth vertically, a connecting rod correction mechanism consisting of the following components is provided. That is, another pair of crankshafts 13 are provided at appropriate positions in the horizontal direction from approximately the middle position of the connecting rod 16, and the horizontal lever 17 is rotatably connected to the crank pin 17', and the other end is attached to the arm of the connecting rod 16. Connect rotatably. The crank radius of the crankshaft 12 is made slightly larger than the crank radius of the other crankshaft 13. This is because if the radii of these two cranks are the same, the movement of the drilling teeth at the tip of the connecting rod becomes a circular motion, so the tilting action of the connecting rod will not be obtained, and the holes created by the drilling teeth will be distorted. This is because the gap becomes too large and the back and forth amplitude of the drilling tooth becomes too large, resulting in the hole becoming oval in shape, and it becomes impossible to insert the drilling tooth vertically into the soil. This is to alleviate the forward tilting effect of the connecting rod, as will be described later. In order to align the drilling teeth and adjust the forward tilting action of the connecting rod, the horizontal lever 17 is inserted into the elongated hole 18 provided at the position overlapping the arm of the connecting rod 16, and the horizontal lever 17 is moved while shifting the two using a suitable fixing means such as a bolt nut. It is formed so that the horizontal distance and bending angle can be adjusted. Furthermore, a spring 19 is provided parallel to and immediately below the horizontal lever 17 to connect the left end protrusion of the horizontal lever 17 and the connecting rod 16. This is to absorb play when connecting the horizontal lever 17 through the elongated hole 18 and to hold the connecting rod 16 as vertically as possible. In addition, the horizontal lever 17
It goes without saying that the configuration is not limited to this as long as it has the same function as above.

According to FIG. 3, a drive shaft 30 extending left and right of a pulley 11 provided at the center of the drilling device 10 passes through the inner vertical steel plates 20a and 20b and has a small pulley 31 at its tip. Furthermore, as shown in FIG. 2, other pulleys 32 and 33 centered around the crankshafts 12 and 13 are attached to a pair of left and right steel plates 20a20.
The diameters of both pulleys are approximately the same. And these pulleys 31, 32,
33 are simultaneously driven by a chain 34. The tension of the chain is further adjusted by the position of another small pulley 35.

The drilling device 10 is mounted by a shaft 23 provided at the tip of an arm extending to the front ends of the steel plates 20a, 20b, and the shaft 23 is rotatable relative to the chassis via the fixing member 6 shown in FIG. is attached to.

A protection plate 24 is provided at the bottom of the drilling device 10 to protect the drilling teeth 22, and holes corresponding to the drilling teeth are bored in this. Also, the beam 4 carries an idler pulley 41 at one end and is biased by a spring.
0 engages the drive belt 7 to keep the belt properly taut, especially when the spacing between the pulley 11 and the power drive pulley changes as the drilling device 10 moves up and down.

FIG. 2 also illustrates a brush device 42 mounted to the rear of the drilling device 10. This device is a core (earth clod formed by drilling) produced by a drilling device.
It is a box-shaped object specially designed to collect. A rotating brush 43, driven by a belt connected to the driven pulley of the drilling device, sweeps the cores collected from the ground to the rear of the brush device;
The core is then stored in a removable container from which the core can be discharged as needed. The brush device pivots about the mounting portion 44 so that the brush lightly engages the ground. In addition to collecting cores, other debris can also be collected from the ground as it passes.

Next, the operation of the punching device will be explained with reference mainly to FIG. 4.

As is clear from FIGS. 2 and 3, the rotational driving force from the drive pulley 11 is transmitted via the rotating shaft 30 to the pulleys 31 provided at both ends thereof, and further via the chain 34 to the two crankshafts. 12,
13. When the crankshaft 12 rotates, the crank pins 15 15a, 15b, 15
The drilling tooth 22 rotates in the order of c and 15d, and at each phase angle, the drilling tooth 22 rotates and descends, is inserted into the soil, then rises and returns to its original position, and repeats this process. At the same time, the crank pin 17' connected to the horizontal lever 17 extending horizontally from the connecting rod 16 is also
7'a, 17'b, 17'c, 17'd.

While the crank pin 15 rotates at a constant speed as described above, its horizontal movement speed is at the top dead center 15a.
As the rotation continues, it decreases to zero at the front end intermediate level 15b, then increases again and reaches the maximum in the backward direction at the bottom dead center 15c, and further decreases to zero again at the rear end intermediate level 15d. Change. This means that crank pin 17'
The same is true for However, since the vehicle moves forward at a substantially constant speed, the phase angle of the crank pin causes a relative speed difference between the horizontal speed of the crank pin and the forward speed of the vehicle. In particular, when the drilling tooth 22 penetrates into the soil at a phase angle near the front end intermediate level 15b, the top end of the connecting rod integrated with the drilling tooth tends to tilt forward because the vehicle moves forward with its tip stationary on the ground. On the other hand, since the crank arm radius of the two crank pins 15 and 17' is larger, the connecting rod is tilted forward near the front end intermediate level 15b by utilizing this difference in radius. Therefore, the front end intermediate level 15b according to the vehicle forward speed
This alleviates the forward tilting effect on the connecting rod in the vicinity and prevents excessive force from acting on the drilling tooth from the connecting rod.

Rotation progresses from front end intermediate level 15b and bottom dead center 1
After passing the intermediate phase angle of 5c, the backward speed of the crank pin 15 increases considerably and reaches the maximum at the bottom dead center 15c. Therefore, an appropriate value of backward speed until this maximum backward speed is reached is determined as the vehicle forward speed. If the adjustment is made so that the connecting rod matches the bottom dead center 15c, the connecting rod is returned to an upright position and the drilling teeth reach their maximum depth near the bottom dead center 15c.
After this phase angle, the rear connecting rod and the drilling teeth are withdrawn in the reverse order. In this extraction process, the upper end of the connecting rod continues to move backward at a speed corresponding to the forward vehicle speed until it reaches around 45 degrees between the bottom dead center 15c and the rear end intermediate level 15d, so it remains almost stationary on the ground. As the crank pin 15 rotates while being held in this state, the connecting rod tilts slightly backwards with respect to the crank mechanism for a very short time, but after passing around the above 45 degrees, the backward speed toward the upper end of the connecting rod suddenly decreases. Therefore, the forward speed of the vehicle becomes greater than this backward speed, and the upper end of the connecting rod is pushed back forward. At this time, since the drilling tooth is being pulled out from the hole drilled in the soil just before, no problem will occur even if the connecting rod tilts forward as described above. At the top dead center, the absolute speed of the top end of the connecting rod relative to the ground is approximately twice the vehicle speed, so it is rapidly moved forward to move on to the next drilling operation.

In the above drilling operation, the correction mechanism of the connecting rod including the horizontal lever 17 operates as follows. The connecting rod 16 is held vertically when the crank pin 15 is at the top dead center as shown in FIG. As previously mentioned,
As the crank pins 15, 17' rotate from the above phase angle, the connecting rod 16 becomes tilted forward (FIG. 4). Then, the horizontal lever 17 is bent at the elongated hole 18. This bending angle becomes maximum when the crank pin 15 reaches the lower point. When this bending occurs, the action of the spring 19 attempts to restore the bend, and the forces are balanced at a balanced point. When the crank 15 passes the bottom dead center and begins to rise, a movement opposite to the above occurs. This compensation mechanism thus acts on the connecting rod 16, including the drilling teeth 22, in order to keep these parts as perpendicular as possible.

〔effect〕

As mentioned above, the horizontal movement speed of the crank pin changes as the crank mechanism rotates, but the horizontal movement speed becomes zero when it reaches the front end intermediate level from top dead center, so the absolute speed at the top of the connecting rod is the vehicle forward speed. The forward tilting effect near the intermediate level of the front end, which is caused by the deviation in relative speed with the lower end of the drilling tooth that has started penetrating into the soil, is alleviated by elastically holding the connecting rod using the correction mechanism of the connecting rod. Therefore, it is possible to prevent the connecting rod and the perforated teeth from breaking due to excessive force, and this is not limited by the forward speed of the chassis. Drilling operations can therefore be carried out at very high speeds. This is because the perforated teeth are integrated with the connecting rod and are directly connected to the crankshaft, and another set of crankshafts is provided separately from the upper crankshaft, and the horizontal lever connected to this crankshaft is connected to the connecting rod. This is achieved by driving both crankshafts to rotate simultaneously, and therefore a simple and strong structure can be obtained. In addition, since the drilling device itself has an independent configuration, it is not fixedly attached to the vehicle body, but can be detachably attached, so the vehicle body can be used not only for drilling work but also for other purposes. It has a remarkable effect that it can also be used for other purposes.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the entire lawn care device according to the present invention, FIG. 2 is an enlarged side view of the perforating device, and FIG.
The figure is a front view (including a partially sectional view), and FIG. 4 is an explanatory diagram of the operation of the punching device. 10...Drilling device, 11...Drive pulley, 1
2, 13... Crankshaft, 15, 17'... Crank pin, 16... Connecting rod, 17... Horizontal lever, 18... Long hole, 19... Spring, 21... Drilling head, 22... Drilling hole teeth.

Claims (1)

[Claims] 1. A lawn care device in which a perforating device comprising a plurality of perforating teeth connected to a rotationally driven crank mechanism that moves up and down via a connecting rod is attached to a vehicle chassis, and the perforating device is driven forward by the power of the vehicle chassis. The device includes an upper crank mechanism, a connecting rod that hangs down from the crank mechanism and is directly connected to the drilling teeth, and a connecting rod that is provided on the lower side of the crank mechanism and is rotated synchronously with the upper crank mechanism so that the radius of rotation is greater than that of the upper crank mechanism. The chassis is equipped with another set of slightly smaller lower crank mechanisms and a correction mechanism consisting of a horizontal lever that is rotatably connected at both ends to the lower crank mechanism and a connecting rod and is extendable and retractable by an elastic member. U with the part shape open to the rear
1. A lawn care device characterized in that the perforation device is removably attached to the open space of the lawn care device formed in the shape of a letter by means of two horizontal pivot shafts provided at the front end of the perforation device.