JPH01295901A - Linear rammer - Google Patents

Abstract

PURPOSE:To miniaturize a device and attenuate noise, by providing the lower end of a piston for performing reciprocating motion in a DC linear motor, with an oil pressure piston via an double-pressure cylinder, and by providing the lower end of the oil pressure piston with a compaction plate, to compose a linear rammer. CONSTITUTION:A rammer is basically composed of a linear motor 1, a piston 3 for performing reciprocating motion in the linear motor 1, an double-pressure cylinder 4 at the lower end of the piston 3, an oil pressure piston 5 fitted at the lower end of the double-pressure cylinder 4, and a compaction plate 7 connected to the oil pressure piston 5. Then, the coil 2 of the linear motor 1 is electrified to push the piston 3 upward, and at the lower end of the stroke of the piston 3, the coil 2 is electrified reverse to move the piston 3 upward, whereby the compaction plate is oscillated. As a result, compared with the rammer of a conventional engine means, the rammer of compact composition can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vibration compaction machine used for compacting soil, asphalt, quarrying, etc. in road construction, building foundation work, etc.

(Prior art) As a small compaction machine, Run 7 is widely used for road construction, backfilling of gas pipes, construction foundation work, etc.
Due to the high operating noise, there are constant complaints from residents near the construction site, and the compaction force is not strong enough, so there is a need to develop a machine that is small, low noise, has strong compaction force, and is easy to handle.

(Problems to be Solved by the Invention) The present invention has been made to solve these problems, and is a compact motor that utilizes the linear motion performance of a DC linear motor, such as large thrust at low speeds, long stroke, and simple structure. The present invention provides a compaction machine with low noise. However, compared to an AC linear motor, the thrust is larger at low speeds, and even with a DC linear motor, it is difficult to obtain enough thrust to directly move a compaction plate with a practical small-volume motor. Furthermore, it is easy to obtain a long stroke as a characteristic of a linear motor. The present invention takes advantage of these characteristics by applying thrust to a small-diameter piston to force it to enter a large-diameter hydraulic cylinder, increasing pressure and optimizing the stroke according to the area ratio, thereby creating a practical compaction force. It was made so that it could be read.

(Example) FIG. 1 is a schematic diagram showing an example of the present invention. The coil 2 of the linear motor 1 is energized to drive the magnetized piston 3, the piston 3 is thrust into the double pressure cylinder 4 provided at the lower end of the piston 3, and is engaged with the double pressure cylinder 4 via hydraulic pressure. Press down the hydraulic piston 5 connected to the hydraulic piston 5, further push down the compaction plate 7 connected to the hydraulic piston 5, and at the lower end of the stroke of the piston 3, the coil 2 is
is reversely energized to reverse the upward movement of the piston 3. The hydraulic piston 5 and the compaction plate 7 are pulled up by the negative pressure of the double pressure cylinder 4 generated during the lifting process. At the upper end of the stroke of the piston 3, the energization of the coil 2 is reversed again to reverse the movement of the piston 3, and the continuous movement of the piston causes the compaction plate 7 to vibrate and compact the ground. The oil port 2 positions the piston 3 in its compression stroke. Note that 14 is the iron core, 15 is the oil tank, and 16
17 indicates a slide bearing, and 17 indicates a dust-proof bellows.

As is well known, when a current is passed through the coil 2 placed in the magnetic flux created by the iron core 14 and the magnetized piston 3, the piston 3 moves in a direction corresponding to the direction of the current. The diameter of the piston 3 is 50 mm, and the diameter of the double pressure cylinder 4 is 1001 mm.
If the thrust of the piston 3 is 20 kgf, the hydraulic piston 5 receives a hydraulic pressure of 80 kgf, and if the stroke of the piston 3 is 1601, the hydraulic piston 5 is
Press down 1+m.

During the upward movement of the piston 3, a negative pressure of 20 kgf is generated and the compaction plate 7 is pulled up. This shows that a sufficient value can be obtained as one impact energy for a small compaction machine.The double pressure cylinder system allows the size of the linear motor to be set to a practical size of 150 to 200 mm in diameter and 300 to 500 mm in length. The detailed structure of the linear motor can be varied depending on the combination of magnetic poles, coils, and iron cores, and is not limited to any country.

FIG. 2 shows a schematic diagram of another embodiment of the invention. linear motor 1
A hydraulic piston that drives a magnetized piston 3 by energizing the coil 2 of the piston 3, causes the piston 3 to enter a double pressure cylinder 4 provided at the lower end of the piston 3, and engages with the double pressure cylinder 4 via hydraulic pressure. 5 is pushed down, and the compaction plate 7 connected to the hydraulic piston 5 is pushed down, and at the lower end of the stroke of the piston 3, the coil 2 is reversely energized by the sensor 8 and the power source 9 to reverse the upward movement of the piston 3.

During the rising process, the rod 10 passing through the piston 3
, an up piston 3 that pulls up the compaction plate via a spring 11
At the upper end of the stroke, the energization of the coil 2 is reversed again, and the compacting plate 7 is vibrated by the continuous movement of the piston to compact the ground.

In FIG. 3, the compaction plate 7 is directly driven by the linear piston 18 without providing a double pressure cylinder, and the movement of the linear piston 18 is transmitted to the compaction plate 7 via the spring 6.11. As mentioned above, a small compaction machine has a thrust of at least 80 to 100 kgf per blow, and a thrust of 30 kgf per blow.
Requires ~40 strokes. Although it is not impossible to directly output this much output from the linear piston 18 using a linear motor of a practical size used as the compaction machine, it is difficult and not a good idea with the current state of the art. However, if there is no restriction on the size of the linear motor, this example can also be put to practical use.

(Effects of the Invention) The conventional run 7 performs vibration compaction by converting engine rotation into linear motion using a crank mechanism, so the machine volume is large, the number of component parts is large, and the obtained vibration frequency is low. On the other hand, the linear rammer of the present invention can obtain linear motion electrically, so the mechanism is simple, the number of components is small, and the volume is small, so it is especially suitable for compacting narrow grooves, and has a mechanical Noise level is low.

[Brief explanation of the drawing]

FIG. 1 shows an example of the present invention, and FIG. 2 shows a schematic diagram of another example.
FIG. 3 shows an example in which no double pressure cylinder is provided. 1... Linear motor, 2... Coil, 3... Piston, 4... Double pressure cylinder, 5... Hydraulic piston,
6... Spring, 7... Compaction plate, 8... Sensor, 9
...power supply, 10...lot, 1]...spring, 1
2...Oil boat, 13...Adjusting nut, 14
...Iron core, 15...Oil tank, 16...Slide bearing, 17...Dust-proof bellows, 18...
・Linear piston, Figure 1 i) 2・“N Note 3 Country

Claims (1)

[Claims] The coil of the linear motor is energized to drive the piston,
The piston is plunged into a double pressure cylinder provided at the lower end of the piston, and the hydraulic piston that engages with the double pressure cylinder and the compaction plate connected to the hydraulic piston are pushed down via hydraulic pressure, and at the lower end of the stroke of the piston, The coil is reversely energized to reverse the upward movement of the piston, and during the upward movement, the hydraulic piston and the compaction plate are raised together, and at the upper end of the piston's stroke, the coil is de-energized again to cause the piston to move. A linear rammer is characterized in that the ground is compacted by a compaction plate by the continuous vibration of the piston.