GB2147948A

GB2147948A - Noise screening apparatus for rotary electric appliances and internal combustion engines

Info

Publication number: GB2147948A
Application number: GB08327325A
Authority: GB
Inventors: Tosai Yasumoto
Original assignee: SANWA CINE EQUIPMENT RENTAL CO
Current assignee: SANWA CINE EQUIPMENT RENTAL CO
Priority date: 1983-10-12
Filing date: 1983-10-12
Publication date: 1985-05-22
Also published as: GB8327325D0

Abstract

Side walls 3, 3' of a noise screening case 2 enclosing the equipment 1 form ventilation paths 6,6' between outer side walls 4,4' and inner side walls 5,5'. Air supply ports 7,7' to the ventilation paths 6,6' are provided in the outer side walls 4,4' adjacent one end of the air paths. Junction ports 8,8' connect the ventilation paths 6,6' and the chamber housing the equipment 1 and are provided in the inner side walls 5,5' at the other end of the air paths. An air discharge port (10, Figs. 2 and 3) of an air discharge path 9 connected to the equipment chamber opens above the case 2. <IMAGE>

Description

SPECIFICATION Noise screening apparatus for rotary electric appliances and internal combustion en- gines, etc.

This invention relates to a noise screening apparatus for rotary electric appliances and internal combustion engines, etc.

In general, when noises from rotary electric appliances and internal combustion engines, etc. are screened, various measures have been taken; for example, rotary electric appliances and internal combustion engines, etc. are enclosed with a noise screening case, and a sound absorbing material is put up on a noise screenig case. By making the wall of the noise screening case thicker or by using a great number of sound absorbing materials, noise can be screened more effectively, but in this case the noise screening case will be larger in size, heavier in weight and further higher in price.

From the above viewpoint, the present invention has objects to promote small size and light weight and to be able to manufacture at low cost as well as to effectively screen noises, and describes a portable noise screening apparatus for rotary electric appliances and internal combustion engines, etc. which, in particular, support a wheel on a lower part thereof by means of an axle, or is loaded on an automobile.

The drawings show an embodiment of the invention, wherein: Figure 1 shows an outlined sectional plane view of the invention; Figure 2 is an outlined sectional view of A-A line of Fg. 1; Figure 3 is an outlined explanatory view of operating condition.

An embodiment of the present invention is explained below with reference to the drawings.

In drawings, numeral 1 is a main equipment, e.g. a rotary electric appliance or an internal combustion engine, etc., numeral 2 is a noise screening case enclosing the main equipment 1 and side walls 3, 3' of the noise screening case 2 is provided with a double structure consisting of outer side walls 4, 4' and inner side walls 5, 5' where ventilation paths 6, 6' are formed.

Air supply ports 7, 7' opening into said ventilation paths 6, 6' are provided on the outer side walls 4, 4' on one side end (left side in Fig. 1) of said side walls 3, 3'. In addition, junction ports 8, 8' opening into said ventilation paths 6, 6' and the inside of the noise screening case 2 housing the main equipment 1 are provided on the inner side walls 5, 5' on the outer side end (right side in Fig. 1) of the side walls 3, 3'.

Numeral 9 is an air discharge path opening into the inside of the noise screening case 2 and an air discharge port 10 of the air discharge path 9 is provided on the upper part of the noise screening case 2.

Numeral 11 is a cooling fan which rotates together with the main equipment 1 and sucks into the noise screening case 2 cool air cooling over the main equipment 1.

The function of the present invention is explained below.

By means of the function of the cooling fan 11 rotating together with the main equipment 1, the air is sucked from the air supply ports 7, 7' provided on the outer side walls 4, 4', flows through the ventilation paths 6, 6' formed between outer side walls 4, 4' and inner side walls 5, 5' and runs into the noise screenig case 2 from the junction ports 8, 8' provided on the inner side walls 5, 5', where the air cools down the main equipment 1, that is, by heat exchange, and the air that becomes discharged air after heat exchange flows through the air discharge path 9 by the cooling fan 11 and is discharged into the atmosphere from the air discharge port 10.

The air supply ports 7, 7' opening into the air and the ventilation paths 6, 6' formed on the side walls 3, 3' of the noise screening case 2 are provided on the outer side walls 4, 4' on one side end of the side walls 3, 3' and further the junction ports 8, 8' opening into the ventilation paths 6, 6' and the inside of the noise screening case 2 are provided on the inner side walls 5, 5' on the other side end of the side walls 3, 3'.Therefore the ventilation paths 6, 6' formed between the outer side walls 4, 4' constituting side walls 3, 3' and the inner side walls 5, 5' are enclosed in almost entire area by the side walls 3, 3' and air entered from the air supply ports 7, 7' provided on the outer side walls 4, 4' passes through the ventilation paths 6, 6' at the highest speed and flows into the noise screening case 2 through the junction ports 8, 8' provided on the inner side walls 5, 5'.

As stated above, since a noise generated by the rotation of the main equipment 1 is screened with air flow running at a high speed through the ventilation paths 6, 6' formed on the side walls 3, 3' of the noise screening case 2, the noise leaking out from the periphery of the noise screening case 2 can be reduced remarkably. For example, in comparison with a noise leaking out to the periphery when the composition of other noise screening devices is under the same condition as stated above, but no ventilation path is formed on a side wall, a noise was reduced by 10-20 phons.

Fig. 3 is an outlined explanatory view showing an example of application of the invention wherein the main equipment 1 of a portable noise screening apparatus has been loaded on an automobile 12.

As described above, according to the present invention, by providing at least the side walls 3, 3' of the noise screening case 2 enclosing the main equipment 1 with a double structure to form the ventilation paths 6, 6' between the outer side walls 4, 4' and the inner side walls 5, 5', as a result that the air supply ports 7, 7' opening into said ventilation paths 6, 6' are provided on the outer side walls 4, 4' on one side end of said side walls 3, 3', the junction ports 8. 8' opening into said ventilation paths 6, 6' and the inside of the noise screening case 2 housing the main equipment 1 are provided on the inner side walls 5, 5' on the other side end of the side walls 3, 3'.In addition the air discharge port 10 of the air discharge path 9 opening into the inside of the noise screening case 2 is provided on the upper part of the noise screening case 2, since a noise generated by the rotation of the main equipment 1 within the noise screening case 2 is screened effectively with air flow running at a high speed through the ventilation paths 6, 6' formed on the side walls 3, 3' of the noise screening case 2 and the noise generating around the noise screening case 2 is reduced, it is convenient to use the noise screening apparatus of the invention as a noise screening device when the anti noise law has been applied to the neighborhood of the place where a rotary electric appliance and an internal combustion engine, etc. being the main equipment 1 is used and is also remarkably convenient to use it as a portable noise screening device when a rotarty electric appliance, etc. is loaded on an automobile because small size and light weight can be produced by a simple arrangement. For example, the noise screening apparatus is the most suitable one as a noise screening device for rotary electric appliances to be used at an outdoor photographing place where noises around the circumference are regulated strictly or as a noise screening device for internal combustion engine being a power source to be used at a construction site in a town.

Claims

1. Noise screening apparatus for sound damping rotary equipment, comprising a housing having at least internal side wall portions which define with juxtaposed wall portions of the housing, respective air flow passages disposed outwardly of an inner chamber of the housing for containing said equipment, there being provided air inlets for allowing air outside the housing to flow into said air flow passages at or adjacent one end thereof, ports at or adjacent the other end of the air flow passages to allow air to flow therefrom into said inner chamber, and an air outlet arranged to discharge air, which has passed through the inner chamber, to the ambient atmosphere at an upper position of the housing.

2. Apparatus as claimed in Claim 1, wherein the air outlet comprises a vent passage which leads from said inner chamber and terminates in an upwardly extending section through which said air is discharged, in use, to the ambient atmosphere.

3. Apparatus as claimed in Claim 1 or Claim 2 wherein said internal side wall portions stop short of an end wall of the housing at said other end of the air flow passages to define therebetween the aforesaid ports.

4. A noise screening apparatus for rotary electric appliances and internal combustion engines, etc., wherein there is provided at least side walls of a noise screening case enclosing a main equipment with a double structure to form ventilation paths between outer side walls and inner side walls, air supply ports opening into said ventilation paths are provided on the outer side walls on one side end of said side walls, junction ports opening into said ventilation paths and the inside of the noise screening case housing the main equipment are provided on the inner side walls on the other side end of the side walls, and in addition an air discharge port of an air discharge path opening into the inside of the noise screenig case is provided on the upper part of the noise screening case.

5. A noise screening apparatus substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.