JPH0544488Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Industrial Application Field) The present invention is applicable to actuators such as air motors that are connected to input shafts and control shafts as a power source for operating machines such as packaging equipment and bundling equipment, or for the purpose of forward/reverse rotation, speed control, etc. Alternatively, the present invention relates to an exhaust silencer for a vacuum-based ventilate pump or the like. (Prior Art) This type of air actuator generates high noise because it rapidly discharges a large amount of compressed air especially when high output is required. Noise is becoming internationally regulated to 85 dBA or less, so it is necessary to suppress the noise emitted by air motors to 90 dBA or less even under severe operating conditions. Air motor suppliers provide accessories such as forward/reverse switching valves, oilers, and filters, as well as mufflers (silencers) specifically designed for each rating so as not to impair the performance of the air motor. It is recommended that it be installed and used when necessary. FIG. 6 shows an example of a conventional air motor a, in which an inexpensive muffler d made of steel or synthetic resin is screwed into an exhaust port c on the opposite side of the output shaft b. Although this muffler can temporarily reduce noise, its silencing effect is not sufficient to reduce the noise level to the above level. If you only use a muffler, the noise can be heard even outside the room. (Problems to be Solved by the Invention) An object of the present invention is to provide a device that compensates for the low silencing effect of the conventional muffler and further reduces the noise generated by the air motor. For this purpose, an attempt was made to connect an air hose to the exhaust port of the muffler and guide it outside to reduce indoor noise, but although this method reduced the noise to some extent, it significantly reduced the power of the air motor. In this respect, the silencer of the present invention needs to have the characteristics of not causing a decrease in air motor power for noise reduction. (Means for Solving the Problems) The present invention was made in order to solve the above-mentioned problems of the prior art. By installing the air motor, a significant noise reduction effect can be obtained without impairing the performance of the air motor. Therefore, the exhaust silencer for air motors, etc. of the present invention has the following configuration:
A generally cylindrical adhered portion that is open toward one end and has an inner diameter substantially equal to the outer diameter of the muffler, and an interior that tapers in diameter contiguously with the adhered portion and terminates in a small-diameter exhaust port at the other end. It is characterized in that it is constructed as a sound deadening cap made of an elastic material such as rubber, which includes a vibrating part having a space. (Function) When the sound deadening cap of the present invention is used by attaching it to the muffler of an air motor, air impact noise, jet noise, etc. that occur when using a conventional muffler alone are absorbed by the vibrating part, and the elastic free vibration energy is absorbed. Since the noise changes to , and then is generated outside through the small-diameter exhaust port, an effective noise reduction effect is achieved without increasing exhaust resistance. (Example) Hereinafter, the exhaust silencing device for an air motor or the like according to the present invention will be specifically described in accordance with an example with reference to FIGS. 1 to 5. FIG. 1 shows a vertical sectional side view of the lower half of an embodiment of the present invention. This exhaust silencer, designated by the generic code 1, is made of an elastic material such as a rubber material with a rubber hardness of about 50 to 60, and consists of a connected attached part 2 and a vibrating part 3, with the attached part facing toward one end. The inner diameter of the muffler 4 is substantially equal to the outer diameter of the muffler 4, which is once formed into an open, generally cylindrical shape and is attached to a muffler 4 (see FIG. 3) of an air motor or the like. On the other hand, the vibrating part 3 is connected to the attached part 2 and is formed so that its diameter gradually decreases toward the other end on the outer side of the muffler, and ends at a small-diameter exhaust port 5 at the other end. This muffler cap-shaped exhaust muffler 1 has a third
As shown in the figure, the muffler 4 is screwed and attached to the exhaust port c on the opposite side of the output shaft b of the air motor a, and is attached to the muffler 4 by fitting with the attachment part 2. Therefore, a semi-closed space 6 serving as a vibration damping chamber is provided between the rear end of the muffler 4 and the vibrating section 3.

[Table] Compared to the conventional technology using only the muffler d shown in Fig. 6, the exhaust silencing device of the present invention shown in Fig. 3 has a noise level of 15 to
It is known that this decreases by about 20dBA. Table 2 shows the results of an experiment comparing the silencing effects of the exhaust silencing device of the present invention and the prior art for an air motor attached to a strap binding device. Noise was measured in the arrangement shown in FIG. 4 for each operating condition of the strapping device: feeding out the strap, tightening the strap in the reverse direction after clamping the end, and feeding at low speed. The strap tension from the dispenser was 10 kg. The noise of the prior art shows the value of the uniform operating condition.

[Table] When the noise of the exhaust silencing device of the present invention was measured at a position 1 m behind the muffler for the ventilly pump e shown in Fig. 5, a similar silencing effect was obtained. (Effects of the invention) According to the invention, the exhaust noise of actuators such as air motors and ventilator pumps can be significantly reduced without substantially impairing their functions.
It is possible to achieve a level that is almost at the level of regulation, and there are advantages such as a slight increase in costs and ease of handling.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional side view of the lower half of an exhaust silencing device according to one embodiment of the present invention, Fig. 2 is a vertical cross-sectional side view of the lower half of another embodiment of the present invention, and Fig. 3 is an exhaust silencing device according to the present invention. A side view showing how the device is attached to the air motor,
Fig. 4 is a diagram showing the noise measurement situation of the air motor, Fig. 5 is a diagram showing the noise measurement situation of the ventilate pump, and Fig. 6 is a side view showing the installation state of the conventional muffler to the air motor. . 1, 1'... Exhaust silencer, 2... Adhesive part, 3
... Vibration part, 4 ... Muffler, 5 ... Exhaust port, 6
...Space, 7...Step, 8...Protrusion, 9,10...
...Flange, 11...Step, 12...Sound level meter, a
...Air motor, b...Output shaft, c...Exhaust port, d...Muffler, e...Venture pump.

Claims (1)

[Scope of utility model registration request] It is made of an elastic material such as rubber, and has a roughly cylindrical shape that is open toward one end and has an inner diameter that is substantially equal to the outer diameter of the muffler, and a diameter that gradually decreases continuously from the attached part to the other end. An exhaust silencing device for an air motor, etc., characterized in that it consists of a vibrating part with an internal space that ends in a small diameter exhaust port, and is fitted and attached to a muffler at the attached part.