JPH0222228Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a vibration isolation structure for a long lance that remotely supports an air hammer of a vibrating tool.

Background In recent years, the effects of low-frequency waves generated by vibrations on the human body have been viewed as a problem.

One of them is occupational diseases caused by vibrating tools. This is due to the low frequency range (16
These are disorders that are thought to be caused by vibrations (below Hz), such as albinism, which causes intermittent paleness of the hands and fingers, and a dulling of sensory organs, such as difficulty in seeing and hearing.

For this reason, guidelines for preventing vibration disorders have been established in Japan, and internationally, guidelines for vibration exposure have been proposed by the International Organization for Standardization (ISO). Evaluations are often made with reference to the 1979 ISO draft.

Prior Art and Its Problems Work using vibrating tools includes, for example, repair work of damaged parts such as cracks and joint breaks in coke oven wall bricks.

These damaged areas are repaired by spraying mortar or thermal spraying, but as a pretreatment, the surface of the damaged area and surrounding deteriorated areas are scraped off using an air hammer to improve mortar adhesion. There is. However, since the damaged area is located in a narrow space, the worker cannot directly hold the air hammer and work on it. For this reason, the air hammer is used by being attached to the tip of a long lance of 3 to 9 m.

Conventional long lances are simply made of multiple metal tubes connected by welding, so they are prone to resonance, and workers must wear anti-vibration gloves when working to prevent injuries. is being carried out. However, wearing gloves alone has a low vibration-proofing effect, and since continuous work cannot be performed, the work must be done intermittently, and the total working time is short, making it impossible to improve work efficiency.

For this reason, it has been desired to develop a long run with anti-vibration measures that can improve work efficiency and prevent vibration problems.

Purpose of the invention This invention substantially satisfies the guidelines for vibration exposure proposed by the above-mentioned ISO, improves work efficiency, and provides vibration isolation effects that reliably prevent vibration disorders, especially in the low frequency range. The purpose of this project is to propose a long lance for air hammers with excellent vibration effects.

Structure of the device This device is a long lance that has an air hammer attached to its tip. A constriction section is provided at the tip of the tube at the hand gripping section, and a two-stage constriction section with a long first stage is installed at the rear end of the tube at the tip. At the same time, a short tube with the same diameter as the lance is externally fitted with a small gap between the tube at the tip, and a part of the circumferential surface is fitted. Insert the constricted part of the hand grip part and the second stage constricted part of the tip from both ends of the vibration-proof rubber short tube with a slight gap, and remove the two-split short tube with the same diameter as the lance. The gist is a long lance for an air hammer that is provided with a vibration-proof part made by fitting and welding the pipe of the hand grip part and the short pipe.

In other words, this idea connects part of a long lance with an air hammer attached to its tip via a vibration-proof rubber tube, thereby absorbing and attenuating the vibrations of the tip where the air hammer is attached.
This is to reduce vibration propagation to the hand grip.

This invention will be explained below based on the drawings.

FIG. 1 is a vertical sectional front view showing the long lance of this invention, FIG. 2 is an enlarged vertical sectional front view of the vibration isolating part, and FIG. 3 is an enlarged plan view of the vibration isolating part.

Reference numeral 1 denotes an air hammer, which is detachably attached to the tip of a long lance 2 and is operated by high pressure air supplied from a compressed air supply pipe 12 attached to the rear end.

The long lance 2 is provided with a vibration isolating part 3 before the pipe 4 of the hand grip part to which the compressed air supply pipe 12 is attached.

The vibration isolating part 3 has a constriction part 5 at the tip of the tube 4 of the hand grip part.
A hose nipple 5 having a hose nipple 5 having a diameter of
7-2, welding the hose nipple 7 internally,
A short vibration-proof rubber tube 8 is fitted into the first constricted portion 7-1 of the hose nipple 7, and a short tube 9 having the same diameter as the lance 2 is connected to the tube 6 at the tip with a small gap S for vibration prevention. It is fitted externally, and a recess 6-1 and a protrusion 9-1 for preventing rotation are provided on a portion of the circumferential surface. Then, the constricted part 5-1 of the hose nipple 5 and the second stage constricted part 7-2 of the hose nipple 7 are inserted from both ends of the vibration-proof rubber short tube 10 with a small gap S' for vibration isolation, and the lance 2 A halved short tube 11 having the same diameter is fitted onto the outside, and the tube 4 of the hand grip portion and the short tube 9 are welded together.

Function Since the vibration-proof lance of this invention has the above-described structure, high-pressure air is supplied from the rear end of the long lance 2,
The vibration of the lance that occurs when the air hammer 1 attached to the tip is activated to scrape off a deteriorated part of the repair site such as the oven wall of the coke oven can be avoided by directly connecting the tube 6 at the tip and the tube 4 at the hand grip. - Anti-vibration rubber short tube 8,
10 and with gaps S and S', the vibrations are absorbed and attenuated on the way without being propagated to the hand grip, and vibrations at the hand grip can be significantly reduced.

Furthermore, since the outer diameter of the vibration isolator 3 is the same as that of the other lance tubes, there is little increase in weight and it is extremely easy to handle.

Here, we used the long lance of this invention and the long lance without conventional anti-vibration measures to improve the anti-vibration effect when pre-treating the repaired area prior to repairing the oven wall of a coke oven. The relationship between the composite vibration level and composite vibration acceleration level with respect to the lance length shown in Figure 4,
The relationship between the vibration acceleration level and the vibration frequency shown in FIG. 5 was also measured.

As a result, it was confirmed that in the low frequency range (below 16Hz), the frequency was below the allowable value of the ISO proposal shown in Figure 6.

Effects of the invention As mentioned above, in this invention, the tip of the air hammer and the hand grip are not directly connected, but are connected via a vibration-proof rubber tube with a gap between them. It is possible to significantly reduce vibration propagation to the machine, improve work efficiency, and reliably prevent vibration problems.

[Brief explanation of drawings]

Figure 1 is a vertical sectional front view showing the long lance of this invention, Figure 2 is an enlarged vertical sectional front view of the vibration isolator, Figure 3 is an enlarged plan view of the vibration isolator, and Figure 4 is the lance length. Figure 5 is a graph showing the measurement results of the vibration isolation effect regarding the relationship between the resultant vibration level and the resultant vibration acceleration level. A graph showing A converted into vibration acceleration level (dB), Figure 6, was published by the International Organization for Standardization (ISO) in 1979.
This is a graph showing the vibration exposure guidelines proposed in 2016. In the figure, 1...Air hammer, 2...Long lance, 3...Vibration isolator, 4...Hand grip tube, 5...
... Hose nipple, 5-1 ... Squeezed part, 6 ... Tip tube, 6-1 ... Concave part, 7 ... Hose nipple, 7-1 ... First stage constricted part, 7-2 ... Second stage Squeezed part, 8...Vibration-proof rubber short tube, 9...Short tube, 9-
1...Convex portion, 10...Vibration-proof rubber short tube, 11...Half-split short tube, 12...Compressed air supply pipe, S, S'...Gap.

Claims (1)

[Scope of utility model registration request] In a long lance that looks like an air hammer is attached to the tip, a constriction part is provided at the tip of the tube in the hand grip, a two-stage constriction part with the first stage being longer is provided at the rear end of the tube at the tip, and the first stage at the tip is longer. A short anti-vibration rubber tube is fitted into the aperture part, and a short tube with the same diameter as the lance is fitted onto the tip tube with a slight gap, and a part of the circumferential surface is fitted with an uneven fit, and the above-mentioned Insert the constricted part of the hand grip and the second stage constricted part of the tip from both ends of the vibration-proof rubber short tube with a slight gap, and fit the two-piece short tube with the same diameter as the lance to the outside of the hand grip. A long lance for an air hammer that is characterized by having a vibration-proof part made by welding a pipe and a short pipe.