JPS6156726B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rammer used for compacting the ground after backfilling or embanking in road construction or the like.

In most of these types of rammers, an inner cylinder with a shoe fixed at the lower end is slidably inserted into an outer cylinder fixed to the main body frame, and a piston rod is inserted into the inner cylinder from the outer cylinder side. , the piston rod and the inner cylinder are connected via a spring, and furthermore, at the connection point between the piston rod and the inner cylinder, stoppers are formed at two positions above and below, and a pair of stoppers is formed between these stoppers. A spring is inserted between the sliders, and the repulsive force of the spring is received through the slider, and a compressive force is applied to the spring. However, with conventional sliders, there is a gap between the piston rod and the inner cylinder to allow air to flow freely, so each time the piston rod or inner cylinder moves up and down, the slider gains momentum without experiencing much air resistance. It often collides with the stopper, giving excessive shock to various parts and making a lot of noise.

In contrast, some models have a rubber cushion installed at the contact point between the slider and the stopper, but if the cushion is made of soft rubber, it will break quickly, and if it is hard, it will not function properly as a cushion. In any case, it has little practical value.

This invention was developed in view of the above-mentioned drawbacks of the conventional machine.
Avoiding violent collisions between the sliders installed above and below the springs and the stoppers of the inner cylinder and the rods inside it, minimizing the impact and noise caused by this collision, and improving the operation and lubrication of the inner cylinders and rods. The system is designed to ensure that oil is supplied without any hindrance, and its gist is that the outer cylinder 3 is fixed to the main body frame 20, and the inner cylinder 2 is slidably inserted into the outer cylinder 3.
and a rod 4 inserted into the inner cylinder 2 and connected to the inner cylinder 2 via a spring 5, the rod 4 having a longitudinal hollow part 6 communicating with at least an upper part of the inner cylinder 2. and a through hole 7 communicating from this hollow part 6 to the inside of the inner cylinder 2, and stoppers 8 and 9 formed at the upper and lower parts of the rod 4, respectively, are formed at the upper and lower parts of the inner cylinder 2, respectively. A through hole 12 is formed in the peripheral wall of the inner cylinder 2 so that the stoppers 10 and 11 are tightly fitted together.
This through hole 12 or the through hole 7 of the rod 4 is at least connected to the upper and lower stoppers 8, 9, 10, 11 of the inner cylinder 2 or the rod 4.
A pair of sliders are provided above and below the spring 5, and a through hole 13 is formed in the outer cylinder 3 and is opened at a position near the center of the inner cylinder 2, and can communicate with the through hole 13 above the through hole 12 of the inner cylinder 2. 14,1
5 is tightly fitted into the inner cylinder 2 and the rod 4 so as to form sealed chambers 16, 17 between the inner cylinder 2 and the stoppers 8, 9, 10, 11 of the rod 4.

The details of this invention will be explained based on the embodiment shown in FIGS.
An oil reservoir chamber 19 is formed in the footblock 18 at a position directly below the inner cylinder 2. The outer cylinder 3 is fixed to a main body frame 20 in a hanging manner, and a prime mover 21 such as an engine is mounted on the main body frame 20, and a support bar 22 is attached to the main body frame 20. The rod 4 is a piston rod (hereinafter referred to as a piston rod), which reciprocates up and down by the drive of a prime mover 21. The shaft of the prime mover 21 includes a centrifugal clutch 23, a pinion gear 24, and a crank gear 2.
5, and are interlocked via a connecting rod 26. At least the part of the piston rod 4 that passes through the inner cylinder 2 is constituted by a cylindrical body, as shown in FIG.
9, the upper end of the hollow portion 6 communicates with the upper part of the inner cylinder 2 through a through hole 27. The upper stopper 8 of the piston rod 4 is integrally connected to the piston rod 4 in the form of a flange, and the lower stopper 9 is a met body and is screwed onto the lower end of the piston rod 4. Further, the upper stopper 10 of the inner cylinder 2 is integrally connected to the circumferential wall of the cylinder 2, and the lower stopper 11 is constituted by a foot block 18 at its end. Needless to say, the outer diameter of the stoppers 8 and 9 of the piston rod 4 is
The dimensions are approximately matched to the inner diameters of the stoppers 10 and 11 of the inner cylinder 2. The through hole 12 of the inner cylinder 2 only needs to be located several centimeters away from the stoppers 10 and 11; the upper through hole 12 opens below the upper stopper 10, and the lower through hole 12 opens below the lower stopper 11. It opens upward. The through hole 7 of the piston rod 4 also opens at a position away from the center of the stoppers 8 and 9. As a result, an annular recess that opens only downward is formed inside the upper end of the inner cylinder 2 by its inner peripheral wall, the stopper 10, the outer peripheral surface of the piston rod 4, and the stopper 8, and the lower end of the inner cylinder 2 Inside, the inner peripheral wall, the stopper 11, the outer peripheral surface of the piston rod 4, and the stopper 9 form an annular recess that opens only upward. Each of the sliders 14 and 15 is slidably fitted into the piston rod 4 and the inner cylinder 2 so as to tightly close the annular recess, and when the sliders 14 and 15 are closer to the stoppers 10 and 11 than the through hole 12 of the inner cylinder 2, is the piston rod 4 and its stopper 8,
9 to form sealed chambers 16 and 17. Although the illustrated spring 5 is a coil spring, other types of springs such as disc springs can also be used. 28 is a bellows that covers the lower half of the outer cylinder 3 and the upper half of the inner cylinder 2;
2 and the through hole 13 of the outer cylinder 3 are opened inside this bellows 28.

In the illustrated example, the through hole 12 of the inner cylinder 2
Although the through hole 7 of the piston rod 4 is opened near the upper and lower stoppers 10 and 11, the through hole 7 of the piston rod 4 may be opened near the stoppers 8 and 9 of the rod 4.

In the above configuration, when the piston rod 4 is lowered, the spring 5 is compressed via the upper stopper 8 and slider 14, and the repulsive force is transmitted to the inner cylinder 2 via the lower slider 15 and stopper 11, cylinder 2
descends. When the piston rod 4 is raised, the spring 5 is compressed via the stopper 9 below it.
The repulsive force acts on the stopper 10 from the upper slider 14, causing the inner cylinder 2 to rise. In this way, the inner cylinder 2 moves up and down following the up and down movement of the piston rod 4. In this case, the air inside 29 of the inner cylinder 2 is
2 and the through hole 13, or to the upper part of the inner cylinder 2 through the through hole 7 and the hollow part 6 of the piston rod 4. The lubricating oil in the oil sump chamber 19 becomes a mist due to vibration, flows into the inner cylinder 2 through the hollow part 6 of the piston rod 4 and the through hole 7, and flows into the slider 1.
It attaches to 4, 15, etc. Therefore, when the piston rod 4 turns up and down, both stoppers 8 and 1
The upper slider 14 separates from 0, or the lower slider 15 separates from both stoppers 9, 11, and after a moment, the sliders 14, 15 contact the stoppers 8, 10, 9, 11 due to the repulsive force of the spring 5. I try to do it, but stoppers 8, 10, 9, 1
1, the sliders 14, 15 close the annular recess, and the stoppers 8, 10,
Since sealed chambers 16, 17 are formed between the sliders 14, 15 and the stoppers 8, 11, the air in these sealed chambers 16, 17 acts as a cushion, and the sliders 14, 15 and the stopper 8,
A severe collision with 10, 9, and 11 is avoided.

Fig. 3 shows another embodiment, in which a bottomed cylindrical mounting part 31 is formed at the lower end of a linking rod 30 that is driven by a prime mover to reciprocate up and down, and an inner cylinder 2 is screwed and fixed to this. There is. The upper stopper 10 of the inner cylinder 2 is constituted by the end surface of the mounting portion 31. Rod 4 has footblock 32
The hollow part 6 is open only upward. 33 is a through hole of the mounting portion 31. 34 is the oil sump chamber, and the foot block 32
It is formed around the protrusion of. Figures 1 and 2
Parts that are equivalent to those in the illustrated example are designated with the same numbers.

As described above, this invention has the inner cylinder and the stopper of the rod inside the inner cylinder tightly fitted together, and the slider fitted tightly between the inner cylinder and the rod, so that the fitting portion between the stoppers and the slider A sealed chamber is formed between the slider and the stopper, and when the slider that has left the stopper comes into contact with the stopper again, the air in the sealed chamber that is formed between them acts as a cushion, and the slider and the stopper There will be no serious conflict between them. As a result, there is no shock associated with violent collisions, minimizing damage to various parts of the aircraft, and noise is reduced, allowing for quiet deployment work.

Furthermore, the inside of the inner cylinder communicates with its upper, lower, and outer circumferential parts through the hollow part of the rod, the through hole in the inner cylinder, and the through hole in the outer cylinder, so the air inside is not compressed. When negative pressure is generated, the air inside flows out and air flows inside, causing the inner cylinder to vibrate lightly as with previous models, and the lubricant mist also disappears as the inner cylinder and rod operate. Since it flows into the inner cylinder, there is no problem with the supply of lubricating oil.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of the rammer of the present invention, FIG. 2 is an enlarged longitudinal sectional view of the main part thereof, and FIG. 3 is an enlarged longitudinal sectional view of the main part of another embodiment. 1...Show, 2...Inner cylinder, 3...
...Outer cylinder, 4...Rod, 5...Spring, 6...Hollow part, 7...Through hole, 8-11...Stopper, 12...Through hole, 13...Through hole, 14,
15...slider, 16, 17...closed room.

Claims (1)

[Claims] 1.Equipped with an outer cylinder fixed to the main body frame, an inner cylinder slidably inserted into the outer cylinder, and a rod inserted into the inner cylinder and coupled to the inner cylinder via a spring. In the rammer, the rod is provided with a longitudinal hollow portion communicating with at least the upper portion of the inner cylinder, and a through hole communicating with the inside of the inner cylinder from the hollow portion, and stoppers formed at the upper and lower portions of the rod, respectively. It is tightly fitted into stoppers formed at the upper and lower parts of the inner cylinder, and a through hole is bored in the peripheral wall of the inner cylinder, and the through hole or the through hole of the rod is at least connected to the upper and lower stoppers of the inner cylinder or the rod. A through hole is formed in the outer cylinder, which opens at a position closer to the center than the inner cylinder, and communicates with the above-mentioned through hole of the inner cylinder, and a pair of sliders installed above and below the spring are connected to the inner cylinder. and a rammer tightly fitted to the inner cylinder and the rod so as to form a sealed chamber with both stoppers of the rod.